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v6.8
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * SuperH on-chip serial module support.  (SCI with no FIFO / with FIFO)
   4 *
   5 *  Copyright (C) 2002 - 2011  Paul Mundt
   6 *  Copyright (C) 2015 Glider bvba
   7 *  Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
   8 *
   9 * based off of the old drivers/char/sh-sci.c by:
  10 *
  11 *   Copyright (C) 1999, 2000  Niibe Yutaka
  12 *   Copyright (C) 2000  Sugioka Toshinobu
  13 *   Modified to support multiple serial ports. Stuart Menefy (May 2000).
  14 *   Modified to support SecureEdge. David McCullough (2002)
  15 *   Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
  16 *   Removed SH7300 support (Jul 2007).
  17 */
  18#undef DEBUG
  19
  20#include <linux/clk.h>
  21#include <linux/console.h>
  22#include <linux/ctype.h>
  23#include <linux/cpufreq.h>
  24#include <linux/delay.h>
  25#include <linux/dmaengine.h>
  26#include <linux/dma-mapping.h>
  27#include <linux/err.h>
  28#include <linux/errno.h>
  29#include <linux/init.h>
  30#include <linux/interrupt.h>
  31#include <linux/ioport.h>
  32#include <linux/ktime.h>
  33#include <linux/major.h>
  34#include <linux/minmax.h>
  35#include <linux/module.h>
  36#include <linux/mm.h>
  37#include <linux/of.h>
 
  38#include <linux/platform_device.h>
  39#include <linux/pm_runtime.h>
  40#include <linux/reset.h>
  41#include <linux/scatterlist.h>
  42#include <linux/serial.h>
  43#include <linux/serial_sci.h>
  44#include <linux/sh_dma.h>
  45#include <linux/slab.h>
  46#include <linux/string.h>
  47#include <linux/sysrq.h>
  48#include <linux/timer.h>
  49#include <linux/tty.h>
  50#include <linux/tty_flip.h>
  51
  52#ifdef CONFIG_SUPERH
  53#include <asm/sh_bios.h>
  54#include <asm/platform_early.h>
  55#endif
  56
  57#include "serial_mctrl_gpio.h"
  58#include "sh-sci.h"
  59
  60/* Offsets into the sci_port->irqs array */
  61enum {
  62	SCIx_ERI_IRQ,
  63	SCIx_RXI_IRQ,
  64	SCIx_TXI_IRQ,
  65	SCIx_BRI_IRQ,
  66	SCIx_DRI_IRQ,
  67	SCIx_TEI_IRQ,
  68	SCIx_NR_IRQS,
  69
  70	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
  71};
  72
  73#define SCIx_IRQ_IS_MUXED(port)			\
  74	((port)->irqs[SCIx_ERI_IRQ] ==	\
  75	 (port)->irqs[SCIx_RXI_IRQ]) ||	\
  76	((port)->irqs[SCIx_ERI_IRQ] &&	\
  77	 ((port)->irqs[SCIx_RXI_IRQ] < 0))
  78
  79enum SCI_CLKS {
  80	SCI_FCK,		/* Functional Clock */
  81	SCI_SCK,		/* Optional External Clock */
  82	SCI_BRG_INT,		/* Optional BRG Internal Clock Source */
  83	SCI_SCIF_CLK,		/* Optional BRG External Clock Source */
  84	SCI_NUM_CLKS
  85};
  86
  87/* Bit x set means sampling rate x + 1 is supported */
  88#define SCI_SR(x)		BIT((x) - 1)
  89#define SCI_SR_RANGE(x, y)	GENMASK((y) - 1, (x) - 1)
  90
  91#define SCI_SR_SCIFAB		SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
  92				SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
  93				SCI_SR(19) | SCI_SR(27)
  94
  95#define min_sr(_port)		ffs((_port)->sampling_rate_mask)
  96#define max_sr(_port)		fls((_port)->sampling_rate_mask)
  97
  98/* Iterate over all supported sampling rates, from high to low */
  99#define for_each_sr(_sr, _port)						\
 100	for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--)	\
 101		if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
 102
 103struct plat_sci_reg {
 104	u8 offset, size;
 105};
 106
 107struct sci_port_params {
 108	const struct plat_sci_reg regs[SCIx_NR_REGS];
 109	unsigned int fifosize;
 110	unsigned int overrun_reg;
 111	unsigned int overrun_mask;
 112	unsigned int sampling_rate_mask;
 113	unsigned int error_mask;
 114	unsigned int error_clear;
 115};
 116
 117struct sci_port {
 118	struct uart_port	port;
 119
 120	/* Platform configuration */
 121	const struct sci_port_params *params;
 122	const struct plat_sci_port *cfg;
 123	unsigned int		sampling_rate_mask;
 124	resource_size_t		reg_size;
 125	struct mctrl_gpios	*gpios;
 126
 127	/* Clocks */
 128	struct clk		*clks[SCI_NUM_CLKS];
 129	unsigned long		clk_rates[SCI_NUM_CLKS];
 130
 131	int			irqs[SCIx_NR_IRQS];
 132	char			*irqstr[SCIx_NR_IRQS];
 133
 134	struct dma_chan			*chan_tx;
 135	struct dma_chan			*chan_rx;
 136
 137#ifdef CONFIG_SERIAL_SH_SCI_DMA
 138	struct dma_chan			*chan_tx_saved;
 139	struct dma_chan			*chan_rx_saved;
 140	dma_cookie_t			cookie_tx;
 141	dma_cookie_t			cookie_rx[2];
 142	dma_cookie_t			active_rx;
 143	dma_addr_t			tx_dma_addr;
 144	unsigned int			tx_dma_len;
 145	struct scatterlist		sg_rx[2];
 146	void				*rx_buf[2];
 147	size_t				buf_len_rx;
 148	struct work_struct		work_tx;
 149	struct hrtimer			rx_timer;
 150	unsigned int			rx_timeout;	/* microseconds */
 151#endif
 152	unsigned int			rx_frame;
 153	int				rx_trigger;
 154	struct timer_list		rx_fifo_timer;
 155	int				rx_fifo_timeout;
 156	u16				hscif_tot;
 157
 158	bool has_rtscts;
 159	bool autorts;
 160};
 161
 162#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
 163
 164static struct sci_port sci_ports[SCI_NPORTS];
 165static unsigned long sci_ports_in_use;
 166static struct uart_driver sci_uart_driver;
 167
 168static inline struct sci_port *
 169to_sci_port(struct uart_port *uart)
 170{
 171	return container_of(uart, struct sci_port, port);
 172}
 173
 174static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
 175	/*
 176	 * Common SCI definitions, dependent on the port's regshift
 177	 * value.
 178	 */
 179	[SCIx_SCI_REGTYPE] = {
 180		.regs = {
 181			[SCSMR]		= { 0x00,  8 },
 182			[SCBRR]		= { 0x01,  8 },
 183			[SCSCR]		= { 0x02,  8 },
 184			[SCxTDR]	= { 0x03,  8 },
 185			[SCxSR]		= { 0x04,  8 },
 186			[SCxRDR]	= { 0x05,  8 },
 187		},
 188		.fifosize = 1,
 189		.overrun_reg = SCxSR,
 190		.overrun_mask = SCI_ORER,
 191		.sampling_rate_mask = SCI_SR(32),
 192		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 193		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 194	},
 195
 196	/*
 197	 * Common definitions for legacy IrDA ports.
 198	 */
 199	[SCIx_IRDA_REGTYPE] = {
 200		.regs = {
 201			[SCSMR]		= { 0x00,  8 },
 202			[SCBRR]		= { 0x02,  8 },
 203			[SCSCR]		= { 0x04,  8 },
 204			[SCxTDR]	= { 0x06,  8 },
 205			[SCxSR]		= { 0x08, 16 },
 206			[SCxRDR]	= { 0x0a,  8 },
 207			[SCFCR]		= { 0x0c,  8 },
 208			[SCFDR]		= { 0x0e, 16 },
 209		},
 210		.fifosize = 1,
 211		.overrun_reg = SCxSR,
 212		.overrun_mask = SCI_ORER,
 213		.sampling_rate_mask = SCI_SR(32),
 214		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 215		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 216	},
 217
 218	/*
 219	 * Common SCIFA definitions.
 220	 */
 221	[SCIx_SCIFA_REGTYPE] = {
 222		.regs = {
 223			[SCSMR]		= { 0x00, 16 },
 224			[SCBRR]		= { 0x04,  8 },
 225			[SCSCR]		= { 0x08, 16 },
 226			[SCxTDR]	= { 0x20,  8 },
 227			[SCxSR]		= { 0x14, 16 },
 228			[SCxRDR]	= { 0x24,  8 },
 229			[SCFCR]		= { 0x18, 16 },
 230			[SCFDR]		= { 0x1c, 16 },
 231			[SCPCR]		= { 0x30, 16 },
 232			[SCPDR]		= { 0x34, 16 },
 233		},
 234		.fifosize = 64,
 235		.overrun_reg = SCxSR,
 236		.overrun_mask = SCIFA_ORER,
 237		.sampling_rate_mask = SCI_SR_SCIFAB,
 238		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 239		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 240	},
 241
 242	/*
 243	 * Common SCIFB definitions.
 244	 */
 245	[SCIx_SCIFB_REGTYPE] = {
 246		.regs = {
 247			[SCSMR]		= { 0x00, 16 },
 248			[SCBRR]		= { 0x04,  8 },
 249			[SCSCR]		= { 0x08, 16 },
 250			[SCxTDR]	= { 0x40,  8 },
 251			[SCxSR]		= { 0x14, 16 },
 252			[SCxRDR]	= { 0x60,  8 },
 253			[SCFCR]		= { 0x18, 16 },
 254			[SCTFDR]	= { 0x38, 16 },
 255			[SCRFDR]	= { 0x3c, 16 },
 256			[SCPCR]		= { 0x30, 16 },
 257			[SCPDR]		= { 0x34, 16 },
 258		},
 259		.fifosize = 256,
 260		.overrun_reg = SCxSR,
 261		.overrun_mask = SCIFA_ORER,
 262		.sampling_rate_mask = SCI_SR_SCIFAB,
 263		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 264		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 265	},
 266
 267	/*
 268	 * Common SH-2(A) SCIF definitions for ports with FIFO data
 269	 * count registers.
 270	 */
 271	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
 272		.regs = {
 273			[SCSMR]		= { 0x00, 16 },
 274			[SCBRR]		= { 0x04,  8 },
 275			[SCSCR]		= { 0x08, 16 },
 276			[SCxTDR]	= { 0x0c,  8 },
 277			[SCxSR]		= { 0x10, 16 },
 278			[SCxRDR]	= { 0x14,  8 },
 279			[SCFCR]		= { 0x18, 16 },
 280			[SCFDR]		= { 0x1c, 16 },
 281			[SCSPTR]	= { 0x20, 16 },
 282			[SCLSR]		= { 0x24, 16 },
 283		},
 284		.fifosize = 16,
 285		.overrun_reg = SCLSR,
 286		.overrun_mask = SCLSR_ORER,
 287		.sampling_rate_mask = SCI_SR(32),
 288		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 289		.error_clear = SCIF_ERROR_CLEAR,
 290	},
 291
 292	/*
 293	 * The "SCIFA" that is in RZ/A2, RZ/G2L and RZ/T.
 294	 * It looks like a normal SCIF with FIFO data, but with a
 295	 * compressed address space. Also, the break out of interrupts
 296	 * are different: ERI/BRI, RXI, TXI, TEI, DRI.
 297	 */
 298	[SCIx_RZ_SCIFA_REGTYPE] = {
 299		.regs = {
 300			[SCSMR]		= { 0x00, 16 },
 301			[SCBRR]		= { 0x02,  8 },
 302			[SCSCR]		= { 0x04, 16 },
 303			[SCxTDR]	= { 0x06,  8 },
 304			[SCxSR]		= { 0x08, 16 },
 305			[SCxRDR]	= { 0x0A,  8 },
 306			[SCFCR]		= { 0x0C, 16 },
 307			[SCFDR]		= { 0x0E, 16 },
 308			[SCSPTR]	= { 0x10, 16 },
 309			[SCLSR]		= { 0x12, 16 },
 310			[SEMR]		= { 0x14, 8 },
 311		},
 312		.fifosize = 16,
 313		.overrun_reg = SCLSR,
 314		.overrun_mask = SCLSR_ORER,
 315		.sampling_rate_mask = SCI_SR(32),
 316		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 317		.error_clear = SCIF_ERROR_CLEAR,
 318	},
 319
 320	/*
 321	 * Common SH-3 SCIF definitions.
 322	 */
 323	[SCIx_SH3_SCIF_REGTYPE] = {
 324		.regs = {
 325			[SCSMR]		= { 0x00,  8 },
 326			[SCBRR]		= { 0x02,  8 },
 327			[SCSCR]		= { 0x04,  8 },
 328			[SCxTDR]	= { 0x06,  8 },
 329			[SCxSR]		= { 0x08, 16 },
 330			[SCxRDR]	= { 0x0a,  8 },
 331			[SCFCR]		= { 0x0c,  8 },
 332			[SCFDR]		= { 0x0e, 16 },
 333		},
 334		.fifosize = 16,
 335		.overrun_reg = SCLSR,
 336		.overrun_mask = SCLSR_ORER,
 337		.sampling_rate_mask = SCI_SR(32),
 338		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 339		.error_clear = SCIF_ERROR_CLEAR,
 340	},
 341
 342	/*
 343	 * Common SH-4(A) SCIF(B) definitions.
 344	 */
 345	[SCIx_SH4_SCIF_REGTYPE] = {
 346		.regs = {
 347			[SCSMR]		= { 0x00, 16 },
 348			[SCBRR]		= { 0x04,  8 },
 349			[SCSCR]		= { 0x08, 16 },
 350			[SCxTDR]	= { 0x0c,  8 },
 351			[SCxSR]		= { 0x10, 16 },
 352			[SCxRDR]	= { 0x14,  8 },
 353			[SCFCR]		= { 0x18, 16 },
 354			[SCFDR]		= { 0x1c, 16 },
 355			[SCSPTR]	= { 0x20, 16 },
 356			[SCLSR]		= { 0x24, 16 },
 357		},
 358		.fifosize = 16,
 359		.overrun_reg = SCLSR,
 360		.overrun_mask = SCLSR_ORER,
 361		.sampling_rate_mask = SCI_SR(32),
 362		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 363		.error_clear = SCIF_ERROR_CLEAR,
 364	},
 365
 366	/*
 367	 * Common SCIF definitions for ports with a Baud Rate Generator for
 368	 * External Clock (BRG).
 369	 */
 370	[SCIx_SH4_SCIF_BRG_REGTYPE] = {
 371		.regs = {
 372			[SCSMR]		= { 0x00, 16 },
 373			[SCBRR]		= { 0x04,  8 },
 374			[SCSCR]		= { 0x08, 16 },
 375			[SCxTDR]	= { 0x0c,  8 },
 376			[SCxSR]		= { 0x10, 16 },
 377			[SCxRDR]	= { 0x14,  8 },
 378			[SCFCR]		= { 0x18, 16 },
 379			[SCFDR]		= { 0x1c, 16 },
 380			[SCSPTR]	= { 0x20, 16 },
 381			[SCLSR]		= { 0x24, 16 },
 382			[SCDL]		= { 0x30, 16 },
 383			[SCCKS]		= { 0x34, 16 },
 384		},
 385		.fifosize = 16,
 386		.overrun_reg = SCLSR,
 387		.overrun_mask = SCLSR_ORER,
 388		.sampling_rate_mask = SCI_SR(32),
 389		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 390		.error_clear = SCIF_ERROR_CLEAR,
 391	},
 392
 393	/*
 394	 * Common HSCIF definitions.
 395	 */
 396	[SCIx_HSCIF_REGTYPE] = {
 397		.regs = {
 398			[SCSMR]		= { 0x00, 16 },
 399			[SCBRR]		= { 0x04,  8 },
 400			[SCSCR]		= { 0x08, 16 },
 401			[SCxTDR]	= { 0x0c,  8 },
 402			[SCxSR]		= { 0x10, 16 },
 403			[SCxRDR]	= { 0x14,  8 },
 404			[SCFCR]		= { 0x18, 16 },
 405			[SCFDR]		= { 0x1c, 16 },
 406			[SCSPTR]	= { 0x20, 16 },
 407			[SCLSR]		= { 0x24, 16 },
 408			[HSSRR]		= { 0x40, 16 },
 409			[SCDL]		= { 0x30, 16 },
 410			[SCCKS]		= { 0x34, 16 },
 411			[HSRTRGR]	= { 0x54, 16 },
 412			[HSTTRGR]	= { 0x58, 16 },
 413		},
 414		.fifosize = 128,
 415		.overrun_reg = SCLSR,
 416		.overrun_mask = SCLSR_ORER,
 417		.sampling_rate_mask = SCI_SR_RANGE(8, 32),
 418		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 419		.error_clear = SCIF_ERROR_CLEAR,
 420	},
 421
 422	/*
 423	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
 424	 * register.
 425	 */
 426	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
 427		.regs = {
 428			[SCSMR]		= { 0x00, 16 },
 429			[SCBRR]		= { 0x04,  8 },
 430			[SCSCR]		= { 0x08, 16 },
 431			[SCxTDR]	= { 0x0c,  8 },
 432			[SCxSR]		= { 0x10, 16 },
 433			[SCxRDR]	= { 0x14,  8 },
 434			[SCFCR]		= { 0x18, 16 },
 435			[SCFDR]		= { 0x1c, 16 },
 436			[SCLSR]		= { 0x24, 16 },
 437		},
 438		.fifosize = 16,
 439		.overrun_reg = SCLSR,
 440		.overrun_mask = SCLSR_ORER,
 441		.sampling_rate_mask = SCI_SR(32),
 442		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 443		.error_clear = SCIF_ERROR_CLEAR,
 444	},
 445
 446	/*
 447	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
 448	 * count registers.
 449	 */
 450	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
 451		.regs = {
 452			[SCSMR]		= { 0x00, 16 },
 453			[SCBRR]		= { 0x04,  8 },
 454			[SCSCR]		= { 0x08, 16 },
 455			[SCxTDR]	= { 0x0c,  8 },
 456			[SCxSR]		= { 0x10, 16 },
 457			[SCxRDR]	= { 0x14,  8 },
 458			[SCFCR]		= { 0x18, 16 },
 459			[SCFDR]		= { 0x1c, 16 },
 460			[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
 461			[SCRFDR]	= { 0x20, 16 },
 462			[SCSPTR]	= { 0x24, 16 },
 463			[SCLSR]		= { 0x28, 16 },
 464		},
 465		.fifosize = 16,
 466		.overrun_reg = SCLSR,
 467		.overrun_mask = SCLSR_ORER,
 468		.sampling_rate_mask = SCI_SR(32),
 469		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 470		.error_clear = SCIF_ERROR_CLEAR,
 471	},
 472
 473	/*
 474	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
 475	 * registers.
 476	 */
 477	[SCIx_SH7705_SCIF_REGTYPE] = {
 478		.regs = {
 479			[SCSMR]		= { 0x00, 16 },
 480			[SCBRR]		= { 0x04,  8 },
 481			[SCSCR]		= { 0x08, 16 },
 482			[SCxTDR]	= { 0x20,  8 },
 483			[SCxSR]		= { 0x14, 16 },
 484			[SCxRDR]	= { 0x24,  8 },
 485			[SCFCR]		= { 0x18, 16 },
 486			[SCFDR]		= { 0x1c, 16 },
 487		},
 488		.fifosize = 64,
 489		.overrun_reg = SCxSR,
 490		.overrun_mask = SCIFA_ORER,
 491		.sampling_rate_mask = SCI_SR(16),
 492		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 493		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 494	},
 495};
 496
 497#define sci_getreg(up, offset)		(&to_sci_port(up)->params->regs[offset])
 498
 499/*
 500 * The "offset" here is rather misleading, in that it refers to an enum
 501 * value relative to the port mapping rather than the fixed offset
 502 * itself, which needs to be manually retrieved from the platform's
 503 * register map for the given port.
 504 */
 505static unsigned int sci_serial_in(struct uart_port *p, int offset)
 506{
 507	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 508
 509	if (reg->size == 8)
 510		return ioread8(p->membase + (reg->offset << p->regshift));
 511	else if (reg->size == 16)
 512		return ioread16(p->membase + (reg->offset << p->regshift));
 513	else
 514		WARN(1, "Invalid register access\n");
 515
 516	return 0;
 517}
 518
 519static void sci_serial_out(struct uart_port *p, int offset, int value)
 520{
 521	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 522
 523	if (reg->size == 8)
 524		iowrite8(value, p->membase + (reg->offset << p->regshift));
 525	else if (reg->size == 16)
 526		iowrite16(value, p->membase + (reg->offset << p->regshift));
 527	else
 528		WARN(1, "Invalid register access\n");
 529}
 530
 531static void sci_port_enable(struct sci_port *sci_port)
 532{
 533	unsigned int i;
 534
 535	if (!sci_port->port.dev)
 536		return;
 537
 538	pm_runtime_get_sync(sci_port->port.dev);
 539
 540	for (i = 0; i < SCI_NUM_CLKS; i++) {
 541		clk_prepare_enable(sci_port->clks[i]);
 542		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
 543	}
 544	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
 545}
 546
 547static void sci_port_disable(struct sci_port *sci_port)
 548{
 549	unsigned int i;
 550
 551	if (!sci_port->port.dev)
 552		return;
 553
 554	for (i = SCI_NUM_CLKS; i-- > 0; )
 555		clk_disable_unprepare(sci_port->clks[i]);
 556
 557	pm_runtime_put_sync(sci_port->port.dev);
 558}
 559
 560static inline unsigned long port_rx_irq_mask(struct uart_port *port)
 561{
 562	/*
 563	 * Not all ports (such as SCIFA) will support REIE. Rather than
 564	 * special-casing the port type, we check the port initialization
 565	 * IRQ enable mask to see whether the IRQ is desired at all. If
 566	 * it's unset, it's logically inferred that there's no point in
 567	 * testing for it.
 568	 */
 569	return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
 570}
 571
 572static void sci_start_tx(struct uart_port *port)
 573{
 574	struct sci_port *s = to_sci_port(port);
 575	unsigned short ctrl;
 576
 577#ifdef CONFIG_SERIAL_SH_SCI_DMA
 578	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 579		u16 new, scr = serial_port_in(port, SCSCR);
 580		if (s->chan_tx)
 581			new = scr | SCSCR_TDRQE;
 582		else
 583			new = scr & ~SCSCR_TDRQE;
 584		if (new != scr)
 585			serial_port_out(port, SCSCR, new);
 586	}
 587
 588	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
 589	    dma_submit_error(s->cookie_tx)) {
 590		if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
 591			/* Switch irq from SCIF to DMA */
 592			disable_irq_nosync(s->irqs[SCIx_TXI_IRQ]);
 593
 594		s->cookie_tx = 0;
 595		schedule_work(&s->work_tx);
 596	}
 597#endif
 598
 599	if (!s->chan_tx || s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE ||
 600	    port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 601		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
 602		ctrl = serial_port_in(port, SCSCR);
 603
 604		/*
 605		 * For SCI, TE (transmit enable) must be set after setting TIE
 606		 * (transmit interrupt enable) or in the same instruction to start
 607		 * the transmit process.
 608		 */
 609		if (port->type == PORT_SCI)
 610			ctrl |= SCSCR_TE;
 611
 612		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
 613	}
 614}
 615
 616static void sci_stop_tx(struct uart_port *port)
 617{
 618	unsigned short ctrl;
 619
 620	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
 621	ctrl = serial_port_in(port, SCSCR);
 622
 623	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 624		ctrl &= ~SCSCR_TDRQE;
 625
 626	ctrl &= ~SCSCR_TIE;
 627
 628	serial_port_out(port, SCSCR, ctrl);
 629
 630#ifdef CONFIG_SERIAL_SH_SCI_DMA
 631	if (to_sci_port(port)->chan_tx &&
 632	    !dma_submit_error(to_sci_port(port)->cookie_tx)) {
 633		dmaengine_terminate_async(to_sci_port(port)->chan_tx);
 634		to_sci_port(port)->cookie_tx = -EINVAL;
 635	}
 636#endif
 637}
 638
 639static void sci_start_rx(struct uart_port *port)
 640{
 641	unsigned short ctrl;
 642
 643	ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
 644
 645	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 646		ctrl &= ~SCSCR_RDRQE;
 647
 648	serial_port_out(port, SCSCR, ctrl);
 649}
 650
 651static void sci_stop_rx(struct uart_port *port)
 652{
 653	unsigned short ctrl;
 654
 655	ctrl = serial_port_in(port, SCSCR);
 656
 657	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 658		ctrl &= ~SCSCR_RDRQE;
 659
 660	ctrl &= ~port_rx_irq_mask(port);
 661
 662	serial_port_out(port, SCSCR, ctrl);
 663}
 664
 665static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
 666{
 667	if (port->type == PORT_SCI) {
 668		/* Just store the mask */
 669		serial_port_out(port, SCxSR, mask);
 670	} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
 671		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
 672		/* Only clear the status bits we want to clear */
 673		serial_port_out(port, SCxSR,
 674				serial_port_in(port, SCxSR) & mask);
 675	} else {
 676		/* Store the mask, clear parity/framing errors */
 677		serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
 678	}
 679}
 680
 681#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
 682    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
 683
 684#ifdef CONFIG_CONSOLE_POLL
 685static int sci_poll_get_char(struct uart_port *port)
 686{
 687	unsigned short status;
 688	int c;
 689
 690	do {
 691		status = serial_port_in(port, SCxSR);
 692		if (status & SCxSR_ERRORS(port)) {
 693			sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
 694			continue;
 695		}
 696		break;
 697	} while (1);
 698
 699	if (!(status & SCxSR_RDxF(port)))
 700		return NO_POLL_CHAR;
 701
 702	c = serial_port_in(port, SCxRDR);
 703
 704	/* Dummy read */
 705	serial_port_in(port, SCxSR);
 706	sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 707
 708	return c;
 709}
 710#endif
 711
 712static void sci_poll_put_char(struct uart_port *port, unsigned char c)
 713{
 714	unsigned short status;
 715
 716	do {
 717		status = serial_port_in(port, SCxSR);
 718	} while (!(status & SCxSR_TDxE(port)));
 719
 720	serial_port_out(port, SCxTDR, c);
 721	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
 722}
 723#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
 724	  CONFIG_SERIAL_SH_SCI_EARLYCON */
 725
 726static void sci_init_pins(struct uart_port *port, unsigned int cflag)
 727{
 728	struct sci_port *s = to_sci_port(port);
 729
 730	/*
 731	 * Use port-specific handler if provided.
 732	 */
 733	if (s->cfg->ops && s->cfg->ops->init_pins) {
 734		s->cfg->ops->init_pins(port, cflag);
 735		return;
 736	}
 737
 738	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 739		u16 data = serial_port_in(port, SCPDR);
 740		u16 ctrl = serial_port_in(port, SCPCR);
 741
 742		/* Enable RXD and TXD pin functions */
 743		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
 744		if (to_sci_port(port)->has_rtscts) {
 745			/* RTS# is output, active low, unless autorts */
 746			if (!(port->mctrl & TIOCM_RTS)) {
 747				ctrl |= SCPCR_RTSC;
 748				data |= SCPDR_RTSD;
 749			} else if (!s->autorts) {
 750				ctrl |= SCPCR_RTSC;
 751				data &= ~SCPDR_RTSD;
 752			} else {
 753				/* Enable RTS# pin function */
 754				ctrl &= ~SCPCR_RTSC;
 755			}
 756			/* Enable CTS# pin function */
 757			ctrl &= ~SCPCR_CTSC;
 758		}
 759		serial_port_out(port, SCPDR, data);
 760		serial_port_out(port, SCPCR, ctrl);
 761	} else if (sci_getreg(port, SCSPTR)->size) {
 762		u16 status = serial_port_in(port, SCSPTR);
 763
 764		/* RTS# is always output; and active low, unless autorts */
 765		status |= SCSPTR_RTSIO;
 766		if (!(port->mctrl & TIOCM_RTS))
 767			status |= SCSPTR_RTSDT;
 768		else if (!s->autorts)
 769			status &= ~SCSPTR_RTSDT;
 770		/* CTS# and SCK are inputs */
 771		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
 772		serial_port_out(port, SCSPTR, status);
 773	}
 774}
 775
 776static int sci_txfill(struct uart_port *port)
 777{
 778	struct sci_port *s = to_sci_port(port);
 779	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 780	const struct plat_sci_reg *reg;
 781
 782	reg = sci_getreg(port, SCTFDR);
 783	if (reg->size)
 784		return serial_port_in(port, SCTFDR) & fifo_mask;
 785
 786	reg = sci_getreg(port, SCFDR);
 787	if (reg->size)
 788		return serial_port_in(port, SCFDR) >> 8;
 789
 790	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
 791}
 792
 793static int sci_txroom(struct uart_port *port)
 794{
 795	return port->fifosize - sci_txfill(port);
 796}
 797
 798static int sci_rxfill(struct uart_port *port)
 799{
 800	struct sci_port *s = to_sci_port(port);
 801	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 802	const struct plat_sci_reg *reg;
 803
 804	reg = sci_getreg(port, SCRFDR);
 805	if (reg->size)
 806		return serial_port_in(port, SCRFDR) & fifo_mask;
 807
 808	reg = sci_getreg(port, SCFDR);
 809	if (reg->size)
 810		return serial_port_in(port, SCFDR) & fifo_mask;
 811
 812	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
 813}
 814
 815/* ********************************************************************** *
 816 *                   the interrupt related routines                       *
 817 * ********************************************************************** */
 818
 819static void sci_transmit_chars(struct uart_port *port)
 820{
 821	struct circ_buf *xmit = &port->state->xmit;
 822	unsigned int stopped = uart_tx_stopped(port);
 823	unsigned short status;
 824	unsigned short ctrl;
 825	int count;
 826
 827	status = serial_port_in(port, SCxSR);
 828	if (!(status & SCxSR_TDxE(port))) {
 829		ctrl = serial_port_in(port, SCSCR);
 830		if (uart_circ_empty(xmit))
 831			ctrl &= ~SCSCR_TIE;
 832		else
 833			ctrl |= SCSCR_TIE;
 834		serial_port_out(port, SCSCR, ctrl);
 835		return;
 836	}
 837
 838	count = sci_txroom(port);
 839
 840	do {
 841		unsigned char c;
 842
 843		if (port->x_char) {
 844			c = port->x_char;
 845			port->x_char = 0;
 846		} else if (!uart_circ_empty(xmit) && !stopped) {
 847			c = xmit->buf[xmit->tail];
 848			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 849		} else if (port->type == PORT_SCI && uart_circ_empty(xmit)) {
 850			ctrl = serial_port_in(port, SCSCR);
 851			ctrl &= ~SCSCR_TE;
 852			serial_port_out(port, SCSCR, ctrl);
 853			return;
 854		} else {
 855			break;
 856		}
 857
 858		serial_port_out(port, SCxTDR, c);
 859
 860		port->icount.tx++;
 861	} while (--count > 0);
 862
 863	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
 864
 865	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 866		uart_write_wakeup(port);
 867	if (uart_circ_empty(xmit)) {
 868		if (port->type == PORT_SCI) {
 869			ctrl = serial_port_in(port, SCSCR);
 870			ctrl &= ~SCSCR_TIE;
 871			ctrl |= SCSCR_TEIE;
 872			serial_port_out(port, SCSCR, ctrl);
 873		}
 874
 875		sci_stop_tx(port);
 876	}
 877}
 878
 879static void sci_receive_chars(struct uart_port *port)
 880{
 881	struct tty_port *tport = &port->state->port;
 882	int i, count, copied = 0;
 883	unsigned short status;
 884	unsigned char flag;
 885
 886	status = serial_port_in(port, SCxSR);
 887	if (!(status & SCxSR_RDxF(port)))
 888		return;
 889
 890	while (1) {
 891		/* Don't copy more bytes than there is room for in the buffer */
 892		count = tty_buffer_request_room(tport, sci_rxfill(port));
 893
 894		/* If for any reason we can't copy more data, we're done! */
 895		if (count == 0)
 896			break;
 897
 898		if (port->type == PORT_SCI) {
 899			char c = serial_port_in(port, SCxRDR);
 900			if (uart_handle_sysrq_char(port, c))
 901				count = 0;
 902			else
 903				tty_insert_flip_char(tport, c, TTY_NORMAL);
 904		} else {
 905			for (i = 0; i < count; i++) {
 906				char c;
 907
 908				if (port->type == PORT_SCIF ||
 909				    port->type == PORT_HSCIF) {
 910					status = serial_port_in(port, SCxSR);
 911					c = serial_port_in(port, SCxRDR);
 912				} else {
 913					c = serial_port_in(port, SCxRDR);
 914					status = serial_port_in(port, SCxSR);
 915				}
 916				if (uart_handle_sysrq_char(port, c)) {
 917					count--; i--;
 918					continue;
 919				}
 920
 921				/* Store data and status */
 922				if (status & SCxSR_FER(port)) {
 923					flag = TTY_FRAME;
 924					port->icount.frame++;
 
 925				} else if (status & SCxSR_PER(port)) {
 926					flag = TTY_PARITY;
 927					port->icount.parity++;
 
 928				} else
 929					flag = TTY_NORMAL;
 930
 931				tty_insert_flip_char(tport, c, flag);
 932			}
 933		}
 934
 935		serial_port_in(port, SCxSR); /* dummy read */
 936		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 937
 938		copied += count;
 939		port->icount.rx += count;
 940	}
 941
 942	if (copied) {
 943		/* Tell the rest of the system the news. New characters! */
 944		tty_flip_buffer_push(tport);
 945	} else {
 946		/* TTY buffers full; read from RX reg to prevent lockup */
 947		serial_port_in(port, SCxRDR);
 948		serial_port_in(port, SCxSR); /* dummy read */
 949		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 950	}
 951}
 952
 953static int sci_handle_errors(struct uart_port *port)
 954{
 955	int copied = 0;
 956	unsigned short status = serial_port_in(port, SCxSR);
 957	struct tty_port *tport = &port->state->port;
 958	struct sci_port *s = to_sci_port(port);
 959
 960	/* Handle overruns */
 961	if (status & s->params->overrun_mask) {
 962		port->icount.overrun++;
 963
 964		/* overrun error */
 965		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
 966			copied++;
 
 
 967	}
 968
 969	if (status & SCxSR_FER(port)) {
 970		/* frame error */
 971		port->icount.frame++;
 972
 973		if (tty_insert_flip_char(tport, 0, TTY_FRAME))
 974			copied++;
 
 
 975	}
 976
 977	if (status & SCxSR_PER(port)) {
 978		/* parity error */
 979		port->icount.parity++;
 980
 981		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
 982			copied++;
 
 
 983	}
 984
 985	if (copied)
 986		tty_flip_buffer_push(tport);
 987
 988	return copied;
 989}
 990
 991static int sci_handle_fifo_overrun(struct uart_port *port)
 992{
 993	struct tty_port *tport = &port->state->port;
 994	struct sci_port *s = to_sci_port(port);
 995	const struct plat_sci_reg *reg;
 996	int copied = 0;
 997	u16 status;
 998
 999	reg = sci_getreg(port, s->params->overrun_reg);
1000	if (!reg->size)
1001		return 0;
1002
1003	status = serial_port_in(port, s->params->overrun_reg);
1004	if (status & s->params->overrun_mask) {
1005		status &= ~s->params->overrun_mask;
1006		serial_port_out(port, s->params->overrun_reg, status);
1007
1008		port->icount.overrun++;
1009
1010		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1011		tty_flip_buffer_push(tport);
 
 
1012		copied++;
1013	}
1014
1015	return copied;
1016}
1017
1018static int sci_handle_breaks(struct uart_port *port)
1019{
1020	int copied = 0;
1021	unsigned short status = serial_port_in(port, SCxSR);
1022	struct tty_port *tport = &port->state->port;
1023
1024	if (uart_handle_break(port))
1025		return 0;
1026
1027	if (status & SCxSR_BRK(port)) {
1028		port->icount.brk++;
1029
1030		/* Notify of BREAK */
1031		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1032			copied++;
 
 
1033	}
1034
1035	if (copied)
1036		tty_flip_buffer_push(tport);
1037
1038	copied += sci_handle_fifo_overrun(port);
1039
1040	return copied;
1041}
1042
1043static int scif_set_rtrg(struct uart_port *port, int rx_trig)
1044{
1045	unsigned int bits;
1046
1047	if (rx_trig >= port->fifosize)
1048		rx_trig = port->fifosize - 1;
1049	if (rx_trig < 1)
1050		rx_trig = 1;
1051
1052	/* HSCIF can be set to an arbitrary level. */
1053	if (sci_getreg(port, HSRTRGR)->size) {
1054		serial_port_out(port, HSRTRGR, rx_trig);
1055		return rx_trig;
1056	}
1057
1058	switch (port->type) {
1059	case PORT_SCIF:
1060		if (rx_trig < 4) {
1061			bits = 0;
1062			rx_trig = 1;
1063		} else if (rx_trig < 8) {
1064			bits = SCFCR_RTRG0;
1065			rx_trig = 4;
1066		} else if (rx_trig < 14) {
1067			bits = SCFCR_RTRG1;
1068			rx_trig = 8;
1069		} else {
1070			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1071			rx_trig = 14;
1072		}
1073		break;
1074	case PORT_SCIFA:
1075	case PORT_SCIFB:
1076		if (rx_trig < 16) {
1077			bits = 0;
1078			rx_trig = 1;
1079		} else if (rx_trig < 32) {
1080			bits = SCFCR_RTRG0;
1081			rx_trig = 16;
1082		} else if (rx_trig < 48) {
1083			bits = SCFCR_RTRG1;
1084			rx_trig = 32;
1085		} else {
1086			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1087			rx_trig = 48;
1088		}
1089		break;
1090	default:
1091		WARN(1, "unknown FIFO configuration");
1092		return 1;
1093	}
1094
1095	serial_port_out(port, SCFCR,
1096		(serial_port_in(port, SCFCR) &
1097		~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1098
1099	return rx_trig;
1100}
1101
1102static int scif_rtrg_enabled(struct uart_port *port)
1103{
1104	if (sci_getreg(port, HSRTRGR)->size)
1105		return serial_port_in(port, HSRTRGR) != 0;
1106	else
1107		return (serial_port_in(port, SCFCR) &
1108			(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1109}
1110
1111static void rx_fifo_timer_fn(struct timer_list *t)
1112{
1113	struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1114	struct uart_port *port = &s->port;
1115
1116	dev_dbg(port->dev, "Rx timed out\n");
1117	scif_set_rtrg(port, 1);
1118}
1119
1120static ssize_t rx_fifo_trigger_show(struct device *dev,
1121				    struct device_attribute *attr, char *buf)
1122{
1123	struct uart_port *port = dev_get_drvdata(dev);
1124	struct sci_port *sci = to_sci_port(port);
1125
1126	return sprintf(buf, "%d\n", sci->rx_trigger);
1127}
1128
1129static ssize_t rx_fifo_trigger_store(struct device *dev,
1130				     struct device_attribute *attr,
1131				     const char *buf, size_t count)
1132{
1133	struct uart_port *port = dev_get_drvdata(dev);
1134	struct sci_port *sci = to_sci_port(port);
1135	int ret;
1136	long r;
1137
1138	ret = kstrtol(buf, 0, &r);
1139	if (ret)
1140		return ret;
1141
1142	sci->rx_trigger = scif_set_rtrg(port, r);
1143	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1144		scif_set_rtrg(port, 1);
1145
1146	return count;
1147}
1148
1149static DEVICE_ATTR_RW(rx_fifo_trigger);
1150
1151static ssize_t rx_fifo_timeout_show(struct device *dev,
1152			       struct device_attribute *attr,
1153			       char *buf)
1154{
1155	struct uart_port *port = dev_get_drvdata(dev);
1156	struct sci_port *sci = to_sci_port(port);
1157	int v;
1158
1159	if (port->type == PORT_HSCIF)
1160		v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1161	else
1162		v = sci->rx_fifo_timeout;
1163
1164	return sprintf(buf, "%d\n", v);
1165}
1166
1167static ssize_t rx_fifo_timeout_store(struct device *dev,
1168				struct device_attribute *attr,
1169				const char *buf,
1170				size_t count)
1171{
1172	struct uart_port *port = dev_get_drvdata(dev);
1173	struct sci_port *sci = to_sci_port(port);
1174	int ret;
1175	long r;
1176
1177	ret = kstrtol(buf, 0, &r);
1178	if (ret)
1179		return ret;
1180
1181	if (port->type == PORT_HSCIF) {
1182		if (r < 0 || r > 3)
1183			return -EINVAL;
1184		sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1185	} else {
1186		sci->rx_fifo_timeout = r;
1187		scif_set_rtrg(port, 1);
1188		if (r > 0)
1189			timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1190	}
1191
1192	return count;
1193}
1194
1195static DEVICE_ATTR_RW(rx_fifo_timeout);
1196
1197
1198#ifdef CONFIG_SERIAL_SH_SCI_DMA
1199static void sci_dma_tx_complete(void *arg)
1200{
1201	struct sci_port *s = arg;
1202	struct uart_port *port = &s->port;
1203	struct circ_buf *xmit = &port->state->xmit;
1204	unsigned long flags;
1205
1206	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1207
1208	uart_port_lock_irqsave(port, &flags);
 
 
 
1209
1210	uart_xmit_advance(port, s->tx_dma_len);
1211
1212	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1213		uart_write_wakeup(port);
1214
1215	if (!uart_circ_empty(xmit)) {
1216		s->cookie_tx = 0;
1217		schedule_work(&s->work_tx);
1218	} else {
1219		s->cookie_tx = -EINVAL;
1220		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
1221		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
1222			u16 ctrl = serial_port_in(port, SCSCR);
1223			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1224			if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
1225				/* Switch irq from DMA to SCIF */
1226				dmaengine_pause(s->chan_tx_saved);
1227				enable_irq(s->irqs[SCIx_TXI_IRQ]);
1228			}
1229		}
1230	}
1231
1232	uart_port_unlock_irqrestore(port, flags);
1233}
1234
1235/* Locking: called with port lock held */
1236static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1237{
1238	struct uart_port *port = &s->port;
1239	struct tty_port *tport = &port->state->port;
1240	int copied;
1241
1242	copied = tty_insert_flip_string(tport, buf, count);
1243	if (copied < count)
1244		port->icount.buf_overrun++;
1245
1246	port->icount.rx += copied;
1247
1248	return copied;
1249}
1250
1251static int sci_dma_rx_find_active(struct sci_port *s)
1252{
1253	unsigned int i;
1254
1255	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1256		if (s->active_rx == s->cookie_rx[i])
1257			return i;
1258
1259	return -1;
1260}
1261
1262static void sci_dma_rx_chan_invalidate(struct sci_port *s)
1263{
1264	unsigned int i;
1265
1266	s->chan_rx = NULL;
1267	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1268		s->cookie_rx[i] = -EINVAL;
1269	s->active_rx = 0;
1270}
1271
1272static void sci_dma_rx_release(struct sci_port *s)
1273{
1274	struct dma_chan *chan = s->chan_rx_saved;
1275
1276	s->chan_rx_saved = NULL;
1277	sci_dma_rx_chan_invalidate(s);
1278	dmaengine_terminate_sync(chan);
1279	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1280			  sg_dma_address(&s->sg_rx[0]));
1281	dma_release_channel(chan);
1282}
1283
1284static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1285{
1286	long sec = usec / 1000000;
1287	long nsec = (usec % 1000000) * 1000;
1288	ktime_t t = ktime_set(sec, nsec);
1289
1290	hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1291}
1292
1293static void sci_dma_rx_reenable_irq(struct sci_port *s)
1294{
1295	struct uart_port *port = &s->port;
1296	u16 scr;
1297
1298	/* Direct new serial port interrupts back to CPU */
1299	scr = serial_port_in(port, SCSCR);
1300	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
1301	    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
1302		enable_irq(s->irqs[SCIx_RXI_IRQ]);
1303		if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
1304			scif_set_rtrg(port, s->rx_trigger);
1305		else
1306			scr &= ~SCSCR_RDRQE;
1307	}
1308	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1309}
1310
1311static void sci_dma_rx_complete(void *arg)
1312{
1313	struct sci_port *s = arg;
1314	struct dma_chan *chan = s->chan_rx;
1315	struct uart_port *port = &s->port;
1316	struct dma_async_tx_descriptor *desc;
1317	unsigned long flags;
1318	int active, count = 0;
1319
1320	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1321		s->active_rx);
1322
1323	uart_port_lock_irqsave(port, &flags);
1324
1325	active = sci_dma_rx_find_active(s);
1326	if (active >= 0)
1327		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1328
1329	start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1330
1331	if (count)
1332		tty_flip_buffer_push(&port->state->port);
1333
1334	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1335				       DMA_DEV_TO_MEM,
1336				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1337	if (!desc)
1338		goto fail;
1339
1340	desc->callback = sci_dma_rx_complete;
1341	desc->callback_param = s;
1342	s->cookie_rx[active] = dmaengine_submit(desc);
1343	if (dma_submit_error(s->cookie_rx[active]))
1344		goto fail;
1345
1346	s->active_rx = s->cookie_rx[!active];
1347
1348	dma_async_issue_pending(chan);
1349
1350	uart_port_unlock_irqrestore(port, flags);
1351	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1352		__func__, s->cookie_rx[active], active, s->active_rx);
1353	return;
1354
1355fail:
1356	uart_port_unlock_irqrestore(port, flags);
1357	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1358	/* Switch to PIO */
1359	uart_port_lock_irqsave(port, &flags);
1360	dmaengine_terminate_async(chan);
1361	sci_dma_rx_chan_invalidate(s);
1362	sci_dma_rx_reenable_irq(s);
1363	uart_port_unlock_irqrestore(port, flags);
1364}
1365
1366static void sci_dma_tx_release(struct sci_port *s)
1367{
1368	struct dma_chan *chan = s->chan_tx_saved;
1369
1370	cancel_work_sync(&s->work_tx);
1371	s->chan_tx_saved = s->chan_tx = NULL;
1372	s->cookie_tx = -EINVAL;
1373	dmaengine_terminate_sync(chan);
1374	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1375			 DMA_TO_DEVICE);
1376	dma_release_channel(chan);
1377}
1378
1379static int sci_dma_rx_submit(struct sci_port *s, bool port_lock_held)
1380{
1381	struct dma_chan *chan = s->chan_rx;
1382	struct uart_port *port = &s->port;
1383	unsigned long flags;
1384	int i;
1385
1386	for (i = 0; i < 2; i++) {
1387		struct scatterlist *sg = &s->sg_rx[i];
1388		struct dma_async_tx_descriptor *desc;
1389
1390		desc = dmaengine_prep_slave_sg(chan,
1391			sg, 1, DMA_DEV_TO_MEM,
1392			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1393		if (!desc)
1394			goto fail;
1395
1396		desc->callback = sci_dma_rx_complete;
1397		desc->callback_param = s;
1398		s->cookie_rx[i] = dmaengine_submit(desc);
1399		if (dma_submit_error(s->cookie_rx[i]))
1400			goto fail;
1401
1402	}
1403
1404	s->active_rx = s->cookie_rx[0];
1405
1406	dma_async_issue_pending(chan);
1407	return 0;
1408
1409fail:
1410	/* Switch to PIO */
1411	if (!port_lock_held)
1412		uart_port_lock_irqsave(port, &flags);
1413	if (i)
1414		dmaengine_terminate_async(chan);
1415	sci_dma_rx_chan_invalidate(s);
1416	sci_start_rx(port);
1417	if (!port_lock_held)
1418		uart_port_unlock_irqrestore(port, flags);
1419	return -EAGAIN;
1420}
1421
1422static void sci_dma_tx_work_fn(struct work_struct *work)
1423{
1424	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1425	struct dma_async_tx_descriptor *desc;
1426	struct dma_chan *chan = s->chan_tx;
1427	struct uart_port *port = &s->port;
1428	struct circ_buf *xmit = &port->state->xmit;
1429	unsigned long flags;
1430	dma_addr_t buf;
1431	int head, tail;
1432
1433	/*
1434	 * DMA is idle now.
1435	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1436	 * offsets and lengths. Since it is a circular buffer, we have to
1437	 * transmit till the end, and then the rest. Take the port lock to get a
1438	 * consistent xmit buffer state.
1439	 */
1440	uart_port_lock_irq(port);
1441	head = xmit->head;
1442	tail = xmit->tail;
1443	buf = s->tx_dma_addr + tail;
1444	s->tx_dma_len = CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE);
 
 
1445	if (!s->tx_dma_len) {
1446		/* Transmit buffer has been flushed */
1447		uart_port_unlock_irq(port);
1448		return;
1449	}
1450
1451	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1452					   DMA_MEM_TO_DEV,
1453					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1454	if (!desc) {
1455		uart_port_unlock_irq(port);
1456		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1457		goto switch_to_pio;
1458	}
1459
1460	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1461				   DMA_TO_DEVICE);
1462
1463	desc->callback = sci_dma_tx_complete;
1464	desc->callback_param = s;
1465	s->cookie_tx = dmaengine_submit(desc);
1466	if (dma_submit_error(s->cookie_tx)) {
1467		uart_port_unlock_irq(port);
1468		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1469		goto switch_to_pio;
1470	}
1471
1472	uart_port_unlock_irq(port);
1473	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1474		__func__, xmit->buf, tail, head, s->cookie_tx);
1475
1476	dma_async_issue_pending(chan);
1477	return;
1478
1479switch_to_pio:
1480	uart_port_lock_irqsave(port, &flags);
1481	s->chan_tx = NULL;
1482	sci_start_tx(port);
1483	uart_port_unlock_irqrestore(port, flags);
1484	return;
1485}
1486
1487static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
1488{
1489	struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1490	struct dma_chan *chan = s->chan_rx;
1491	struct uart_port *port = &s->port;
1492	struct dma_tx_state state;
1493	enum dma_status status;
1494	unsigned long flags;
1495	unsigned int read;
1496	int active, count;
1497
1498	dev_dbg(port->dev, "DMA Rx timed out\n");
1499
1500	uart_port_lock_irqsave(port, &flags);
1501
1502	active = sci_dma_rx_find_active(s);
1503	if (active < 0) {
1504		uart_port_unlock_irqrestore(port, flags);
1505		return HRTIMER_NORESTART;
1506	}
1507
1508	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1509	if (status == DMA_COMPLETE) {
1510		uart_port_unlock_irqrestore(port, flags);
1511		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1512			s->active_rx, active);
1513
1514		/* Let packet complete handler take care of the packet */
1515		return HRTIMER_NORESTART;
1516	}
1517
1518	dmaengine_pause(chan);
1519
1520	/*
1521	 * sometimes DMA transfer doesn't stop even if it is stopped and
1522	 * data keeps on coming until transaction is complete so check
1523	 * for DMA_COMPLETE again
1524	 * Let packet complete handler take care of the packet
1525	 */
1526	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1527	if (status == DMA_COMPLETE) {
1528		uart_port_unlock_irqrestore(port, flags);
1529		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1530		return HRTIMER_NORESTART;
1531	}
1532
1533	/* Handle incomplete DMA receive */
1534	dmaengine_terminate_async(s->chan_rx);
1535	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1536
1537	if (read) {
1538		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1539		if (count)
1540			tty_flip_buffer_push(&port->state->port);
1541	}
1542
1543	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
1544	    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
1545		sci_dma_rx_submit(s, true);
1546
1547	sci_dma_rx_reenable_irq(s);
1548
1549	uart_port_unlock_irqrestore(port, flags);
1550
1551	return HRTIMER_NORESTART;
1552}
1553
1554static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1555					     enum dma_transfer_direction dir)
1556{
1557	struct dma_chan *chan;
1558	struct dma_slave_config cfg;
1559	int ret;
1560
1561	chan = dma_request_chan(port->dev, dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1562	if (IS_ERR(chan)) {
1563		dev_dbg(port->dev, "dma_request_chan failed\n");
 
1564		return NULL;
1565	}
1566
1567	memset(&cfg, 0, sizeof(cfg));
1568	cfg.direction = dir;
1569	cfg.dst_addr = port->mapbase +
1570		(sci_getreg(port, SCxTDR)->offset << port->regshift);
1571	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1572	cfg.src_addr = port->mapbase +
1573		(sci_getreg(port, SCxRDR)->offset << port->regshift);
1574	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 
 
 
1575
1576	ret = dmaengine_slave_config(chan, &cfg);
1577	if (ret) {
1578		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1579		dma_release_channel(chan);
1580		return NULL;
1581	}
1582
1583	return chan;
1584}
1585
1586static void sci_request_dma(struct uart_port *port)
1587{
1588	struct sci_port *s = to_sci_port(port);
1589	struct dma_chan *chan;
1590
1591	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1592
1593	/*
1594	 * DMA on console may interfere with Kernel log messages which use
1595	 * plain putchar(). So, simply don't use it with a console.
1596	 */
1597	if (uart_console(port))
1598		return;
1599
1600	if (!port->dev->of_node)
1601		return;
1602
1603	s->cookie_tx = -EINVAL;
1604
1605	/*
1606	 * Don't request a dma channel if no channel was specified
1607	 * in the device tree.
1608	 */
1609	if (!of_property_present(port->dev->of_node, "dmas"))
1610		return;
1611
1612	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1613	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1614	if (chan) {
1615		/* UART circular tx buffer is an aligned page. */
1616		s->tx_dma_addr = dma_map_single(chan->device->dev,
1617						port->state->xmit.buf,
1618						UART_XMIT_SIZE,
1619						DMA_TO_DEVICE);
1620		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1621			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1622			dma_release_channel(chan);
1623		} else {
1624			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1625				__func__, UART_XMIT_SIZE,
1626				port->state->xmit.buf, &s->tx_dma_addr);
1627
1628			INIT_WORK(&s->work_tx, sci_dma_tx_work_fn);
1629			s->chan_tx_saved = s->chan_tx = chan;
1630		}
1631	}
1632
1633	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1634	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1635	if (chan) {
1636		unsigned int i;
1637		dma_addr_t dma;
1638		void *buf;
1639
1640		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1641		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1642					 &dma, GFP_KERNEL);
1643		if (!buf) {
1644			dev_warn(port->dev,
1645				 "Failed to allocate Rx dma buffer, using PIO\n");
1646			dma_release_channel(chan);
1647			return;
1648		}
1649
1650		for (i = 0; i < 2; i++) {
1651			struct scatterlist *sg = &s->sg_rx[i];
1652
1653			sg_init_table(sg, 1);
1654			s->rx_buf[i] = buf;
1655			sg_dma_address(sg) = dma;
1656			sg_dma_len(sg) = s->buf_len_rx;
1657
1658			buf += s->buf_len_rx;
1659			dma += s->buf_len_rx;
1660		}
1661
1662		hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1663		s->rx_timer.function = sci_dma_rx_timer_fn;
1664
1665		s->chan_rx_saved = s->chan_rx = chan;
1666
1667		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
1668		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE)
1669			sci_dma_rx_submit(s, false);
1670	}
1671}
1672
1673static void sci_free_dma(struct uart_port *port)
1674{
1675	struct sci_port *s = to_sci_port(port);
1676
1677	if (s->chan_tx_saved)
1678		sci_dma_tx_release(s);
1679	if (s->chan_rx_saved)
1680		sci_dma_rx_release(s);
1681}
1682
1683static void sci_flush_buffer(struct uart_port *port)
1684{
1685	struct sci_port *s = to_sci_port(port);
1686
1687	/*
1688	 * In uart_flush_buffer(), the xmit circular buffer has just been
1689	 * cleared, so we have to reset tx_dma_len accordingly, and stop any
1690	 * pending transfers
1691	 */
1692	s->tx_dma_len = 0;
1693	if (s->chan_tx) {
1694		dmaengine_terminate_async(s->chan_tx);
1695		s->cookie_tx = -EINVAL;
1696	}
1697}
1698#else /* !CONFIG_SERIAL_SH_SCI_DMA */
1699static inline void sci_request_dma(struct uart_port *port)
1700{
1701}
1702
1703static inline void sci_free_dma(struct uart_port *port)
1704{
1705}
1706
1707#define sci_flush_buffer	NULL
1708#endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1709
1710static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1711{
1712	struct uart_port *port = ptr;
1713	struct sci_port *s = to_sci_port(port);
1714
1715#ifdef CONFIG_SERIAL_SH_SCI_DMA
1716	if (s->chan_rx) {
1717		u16 scr = serial_port_in(port, SCSCR);
1718		u16 ssr = serial_port_in(port, SCxSR);
1719
1720		/* Disable future Rx interrupts */
1721		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB ||
1722		    s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
1723			disable_irq_nosync(s->irqs[SCIx_RXI_IRQ]);
1724			if (s->cfg->regtype == SCIx_RZ_SCIFA_REGTYPE) {
1725				scif_set_rtrg(port, 1);
1726				scr |= SCSCR_RIE;
1727			} else {
1728				scr |= SCSCR_RDRQE;
1729			}
1730		} else {
1731			if (sci_dma_rx_submit(s, false) < 0)
1732				goto handle_pio;
1733
1734			scr &= ~SCSCR_RIE;
1735		}
1736		serial_port_out(port, SCSCR, scr);
1737		/* Clear current interrupt */
1738		serial_port_out(port, SCxSR,
1739				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1740		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1741			jiffies, s->rx_timeout);
1742		start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1743
1744		return IRQ_HANDLED;
1745	}
1746
1747handle_pio:
1748#endif
1749
1750	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1751		if (!scif_rtrg_enabled(port))
1752			scif_set_rtrg(port, s->rx_trigger);
1753
1754		mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1755			  s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1756	}
1757
1758	/* I think sci_receive_chars has to be called irrespective
1759	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1760	 * to be disabled?
1761	 */
1762	sci_receive_chars(port);
1763
1764	return IRQ_HANDLED;
1765}
1766
1767static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1768{
1769	struct uart_port *port = ptr;
1770	unsigned long flags;
1771
1772	uart_port_lock_irqsave(port, &flags);
1773	sci_transmit_chars(port);
1774	uart_port_unlock_irqrestore(port, flags);
1775
1776	return IRQ_HANDLED;
1777}
1778
1779static irqreturn_t sci_tx_end_interrupt(int irq, void *ptr)
1780{
1781	struct uart_port *port = ptr;
1782	unsigned long flags;
1783	unsigned short ctrl;
1784
1785	if (port->type != PORT_SCI)
1786		return sci_tx_interrupt(irq, ptr);
1787
1788	uart_port_lock_irqsave(port, &flags);
1789	ctrl = serial_port_in(port, SCSCR);
1790	ctrl &= ~(SCSCR_TE | SCSCR_TEIE);
1791	serial_port_out(port, SCSCR, ctrl);
1792	uart_port_unlock_irqrestore(port, flags);
1793
1794	return IRQ_HANDLED;
1795}
1796
1797static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1798{
1799	struct uart_port *port = ptr;
1800
1801	/* Handle BREAKs */
1802	sci_handle_breaks(port);
1803
1804	/* drop invalid character received before break was detected */
1805	serial_port_in(port, SCxRDR);
1806
1807	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1808
1809	return IRQ_HANDLED;
1810}
1811
1812static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1813{
1814	struct uart_port *port = ptr;
1815	struct sci_port *s = to_sci_port(port);
1816
1817	if (s->irqs[SCIx_ERI_IRQ] == s->irqs[SCIx_BRI_IRQ]) {
1818		/* Break and Error interrupts are muxed */
1819		unsigned short ssr_status = serial_port_in(port, SCxSR);
1820
1821		/* Break Interrupt */
1822		if (ssr_status & SCxSR_BRK(port))
1823			sci_br_interrupt(irq, ptr);
1824
1825		/* Break only? */
1826		if (!(ssr_status & SCxSR_ERRORS(port)))
1827			return IRQ_HANDLED;
1828	}
1829
1830	/* Handle errors */
1831	if (port->type == PORT_SCI) {
1832		if (sci_handle_errors(port)) {
1833			/* discard character in rx buffer */
1834			serial_port_in(port, SCxSR);
1835			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1836		}
1837	} else {
1838		sci_handle_fifo_overrun(port);
1839		if (!s->chan_rx)
1840			sci_receive_chars(port);
1841	}
1842
1843	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1844
1845	/* Kick the transmission */
1846	if (!s->chan_tx)
1847		sci_tx_interrupt(irq, ptr);
1848
1849	return IRQ_HANDLED;
1850}
1851
1852static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1853{
1854	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1855	struct uart_port *port = ptr;
1856	struct sci_port *s = to_sci_port(port);
1857	irqreturn_t ret = IRQ_NONE;
1858
1859	ssr_status = serial_port_in(port, SCxSR);
1860	scr_status = serial_port_in(port, SCSCR);
1861	if (s->params->overrun_reg == SCxSR)
1862		orer_status = ssr_status;
1863	else if (sci_getreg(port, s->params->overrun_reg)->size)
1864		orer_status = serial_port_in(port, s->params->overrun_reg);
1865
1866	err_enabled = scr_status & port_rx_irq_mask(port);
1867
1868	/* Tx Interrupt */
1869	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1870	    !s->chan_tx)
1871		ret = sci_tx_interrupt(irq, ptr);
1872
1873	/*
1874	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1875	 * DR flags
1876	 */
1877	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1878	    (scr_status & SCSCR_RIE))
1879		ret = sci_rx_interrupt(irq, ptr);
1880
1881	/* Error Interrupt */
1882	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1883		ret = sci_er_interrupt(irq, ptr);
1884
1885	/* Break Interrupt */
1886	if (s->irqs[SCIx_ERI_IRQ] != s->irqs[SCIx_BRI_IRQ] &&
1887	    (ssr_status & SCxSR_BRK(port)) && err_enabled)
1888		ret = sci_br_interrupt(irq, ptr);
1889
1890	/* Overrun Interrupt */
1891	if (orer_status & s->params->overrun_mask) {
1892		sci_handle_fifo_overrun(port);
1893		ret = IRQ_HANDLED;
1894	}
1895
1896	return ret;
1897}
1898
1899static const struct sci_irq_desc {
1900	const char	*desc;
1901	irq_handler_t	handler;
1902} sci_irq_desc[] = {
1903	/*
1904	 * Split out handlers, the default case.
1905	 */
1906	[SCIx_ERI_IRQ] = {
1907		.desc = "rx err",
1908		.handler = sci_er_interrupt,
1909	},
1910
1911	[SCIx_RXI_IRQ] = {
1912		.desc = "rx full",
1913		.handler = sci_rx_interrupt,
1914	},
1915
1916	[SCIx_TXI_IRQ] = {
1917		.desc = "tx empty",
1918		.handler = sci_tx_interrupt,
1919	},
1920
1921	[SCIx_BRI_IRQ] = {
1922		.desc = "break",
1923		.handler = sci_br_interrupt,
1924	},
1925
1926	[SCIx_DRI_IRQ] = {
1927		.desc = "rx ready",
1928		.handler = sci_rx_interrupt,
1929	},
1930
1931	[SCIx_TEI_IRQ] = {
1932		.desc = "tx end",
1933		.handler = sci_tx_end_interrupt,
1934	},
1935
1936	/*
1937	 * Special muxed handler.
1938	 */
1939	[SCIx_MUX_IRQ] = {
1940		.desc = "mux",
1941		.handler = sci_mpxed_interrupt,
1942	},
1943};
1944
1945static int sci_request_irq(struct sci_port *port)
1946{
1947	struct uart_port *up = &port->port;
1948	int i, j, w, ret = 0;
1949
1950	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1951		const struct sci_irq_desc *desc;
1952		int irq;
1953
1954		/* Check if already registered (muxed) */
1955		for (w = 0; w < i; w++)
1956			if (port->irqs[w] == port->irqs[i])
1957				w = i + 1;
1958		if (w > i)
1959			continue;
1960
1961		if (SCIx_IRQ_IS_MUXED(port)) {
1962			i = SCIx_MUX_IRQ;
1963			irq = up->irq;
1964		} else {
1965			irq = port->irqs[i];
1966
1967			/*
1968			 * Certain port types won't support all of the
1969			 * available interrupt sources.
1970			 */
1971			if (unlikely(irq < 0))
1972				continue;
1973		}
1974
1975		desc = sci_irq_desc + i;
1976		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1977					    dev_name(up->dev), desc->desc);
1978		if (!port->irqstr[j]) {
1979			ret = -ENOMEM;
1980			goto out_nomem;
1981		}
1982
1983		ret = request_irq(irq, desc->handler, up->irqflags,
1984				  port->irqstr[j], port);
1985		if (unlikely(ret)) {
1986			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1987			goto out_noirq;
1988		}
1989	}
1990
1991	return 0;
1992
1993out_noirq:
1994	while (--i >= 0)
1995		free_irq(port->irqs[i], port);
1996
1997out_nomem:
1998	while (--j >= 0)
1999		kfree(port->irqstr[j]);
2000
2001	return ret;
2002}
2003
2004static void sci_free_irq(struct sci_port *port)
2005{
2006	int i, j;
2007
2008	/*
2009	 * Intentionally in reverse order so we iterate over the muxed
2010	 * IRQ first.
2011	 */
2012	for (i = 0; i < SCIx_NR_IRQS; i++) {
2013		int irq = port->irqs[i];
2014
2015		/*
2016		 * Certain port types won't support all of the available
2017		 * interrupt sources.
2018		 */
2019		if (unlikely(irq < 0))
2020			continue;
2021
2022		/* Check if already freed (irq was muxed) */
2023		for (j = 0; j < i; j++)
2024			if (port->irqs[j] == irq)
2025				j = i + 1;
2026		if (j > i)
2027			continue;
2028
2029		free_irq(port->irqs[i], port);
2030		kfree(port->irqstr[i]);
2031
2032		if (SCIx_IRQ_IS_MUXED(port)) {
2033			/* If there's only one IRQ, we're done. */
2034			return;
2035		}
2036	}
2037}
2038
2039static unsigned int sci_tx_empty(struct uart_port *port)
2040{
2041	unsigned short status = serial_port_in(port, SCxSR);
2042	unsigned short in_tx_fifo = sci_txfill(port);
2043
2044	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
2045}
2046
2047static void sci_set_rts(struct uart_port *port, bool state)
2048{
2049	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2050		u16 data = serial_port_in(port, SCPDR);
2051
2052		/* Active low */
2053		if (state)
2054			data &= ~SCPDR_RTSD;
2055		else
2056			data |= SCPDR_RTSD;
2057		serial_port_out(port, SCPDR, data);
2058
2059		/* RTS# is output */
2060		serial_port_out(port, SCPCR,
2061				serial_port_in(port, SCPCR) | SCPCR_RTSC);
2062	} else if (sci_getreg(port, SCSPTR)->size) {
2063		u16 ctrl = serial_port_in(port, SCSPTR);
2064
2065		/* Active low */
2066		if (state)
2067			ctrl &= ~SCSPTR_RTSDT;
2068		else
2069			ctrl |= SCSPTR_RTSDT;
2070		serial_port_out(port, SCSPTR, ctrl);
2071	}
2072}
2073
2074static bool sci_get_cts(struct uart_port *port)
2075{
2076	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2077		/* Active low */
2078		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
2079	} else if (sci_getreg(port, SCSPTR)->size) {
2080		/* Active low */
2081		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
2082	}
2083
2084	return true;
2085}
2086
2087/*
2088 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
2089 * CTS/RTS is supported in hardware by at least one port and controlled
2090 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
2091 * handled via the ->init_pins() op, which is a bit of a one-way street,
2092 * lacking any ability to defer pin control -- this will later be
2093 * converted over to the GPIO framework).
2094 *
2095 * Other modes (such as loopback) are supported generically on certain
2096 * port types, but not others. For these it's sufficient to test for the
2097 * existence of the support register and simply ignore the port type.
2098 */
2099static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
2100{
2101	struct sci_port *s = to_sci_port(port);
2102
2103	if (mctrl & TIOCM_LOOP) {
2104		const struct plat_sci_reg *reg;
2105
2106		/*
2107		 * Standard loopback mode for SCFCR ports.
2108		 */
2109		reg = sci_getreg(port, SCFCR);
2110		if (reg->size)
2111			serial_port_out(port, SCFCR,
2112					serial_port_in(port, SCFCR) |
2113					SCFCR_LOOP);
2114	}
2115
2116	mctrl_gpio_set(s->gpios, mctrl);
2117
2118	if (!s->has_rtscts)
2119		return;
2120
2121	if (!(mctrl & TIOCM_RTS)) {
2122		/* Disable Auto RTS */
2123		serial_port_out(port, SCFCR,
2124				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
2125
2126		/* Clear RTS */
2127		sci_set_rts(port, 0);
2128	} else if (s->autorts) {
2129		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2130			/* Enable RTS# pin function */
2131			serial_port_out(port, SCPCR,
2132				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
2133		}
2134
2135		/* Enable Auto RTS */
2136		serial_port_out(port, SCFCR,
2137				serial_port_in(port, SCFCR) | SCFCR_MCE);
2138	} else {
2139		/* Set RTS */
2140		sci_set_rts(port, 1);
2141	}
2142}
2143
2144static unsigned int sci_get_mctrl(struct uart_port *port)
2145{
2146	struct sci_port *s = to_sci_port(port);
2147	struct mctrl_gpios *gpios = s->gpios;
2148	unsigned int mctrl = 0;
2149
2150	mctrl_gpio_get(gpios, &mctrl);
2151
2152	/*
2153	 * CTS/RTS is handled in hardware when supported, while nothing
2154	 * else is wired up.
2155	 */
2156	if (s->autorts) {
2157		if (sci_get_cts(port))
2158			mctrl |= TIOCM_CTS;
2159	} else if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS)) {
2160		mctrl |= TIOCM_CTS;
2161	}
2162	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR))
2163		mctrl |= TIOCM_DSR;
2164	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD))
2165		mctrl |= TIOCM_CAR;
2166
2167	return mctrl;
2168}
2169
2170static void sci_enable_ms(struct uart_port *port)
2171{
2172	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2173}
2174
2175static void sci_break_ctl(struct uart_port *port, int break_state)
2176{
2177	unsigned short scscr, scsptr;
2178	unsigned long flags;
2179
2180	/* check whether the port has SCSPTR */
2181	if (!sci_getreg(port, SCSPTR)->size) {
2182		/*
2183		 * Not supported by hardware. Most parts couple break and rx
2184		 * interrupts together, with break detection always enabled.
2185		 */
2186		return;
2187	}
2188
2189	uart_port_lock_irqsave(port, &flags);
2190	scsptr = serial_port_in(port, SCSPTR);
2191	scscr = serial_port_in(port, SCSCR);
2192
2193	if (break_state == -1) {
2194		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2195		scscr &= ~SCSCR_TE;
2196	} else {
2197		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2198		scscr |= SCSCR_TE;
2199	}
2200
2201	serial_port_out(port, SCSPTR, scsptr);
2202	serial_port_out(port, SCSCR, scscr);
2203	uart_port_unlock_irqrestore(port, flags);
2204}
2205
2206static int sci_startup(struct uart_port *port)
2207{
2208	struct sci_port *s = to_sci_port(port);
2209	int ret;
2210
2211	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2212
2213	sci_request_dma(port);
2214
2215	ret = sci_request_irq(s);
2216	if (unlikely(ret < 0)) {
2217		sci_free_dma(port);
2218		return ret;
2219	}
2220
2221	return 0;
2222}
2223
2224static void sci_shutdown(struct uart_port *port)
2225{
2226	struct sci_port *s = to_sci_port(port);
2227	unsigned long flags;
2228	u16 scr;
2229
2230	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2231
2232	s->autorts = false;
2233	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2234
2235	uart_port_lock_irqsave(port, &flags);
2236	sci_stop_rx(port);
2237	sci_stop_tx(port);
2238	/*
2239	 * Stop RX and TX, disable related interrupts, keep clock source
2240	 * and HSCIF TOT bits
2241	 */
2242	scr = serial_port_in(port, SCSCR);
2243	serial_port_out(port, SCSCR, scr &
2244			(SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2245	uart_port_unlock_irqrestore(port, flags);
2246
2247#ifdef CONFIG_SERIAL_SH_SCI_DMA
2248	if (s->chan_rx_saved) {
2249		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2250			port->line);
2251		hrtimer_cancel(&s->rx_timer);
2252	}
2253#endif
2254
2255	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
2256		del_timer_sync(&s->rx_fifo_timer);
2257	sci_free_irq(s);
2258	sci_free_dma(port);
2259}
2260
2261static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2262			unsigned int *srr)
2263{
2264	unsigned long freq = s->clk_rates[SCI_SCK];
2265	int err, min_err = INT_MAX;
2266	unsigned int sr;
2267
2268	if (s->port.type != PORT_HSCIF)
2269		freq *= 2;
2270
2271	for_each_sr(sr, s) {
2272		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2273		if (abs(err) >= abs(min_err))
2274			continue;
2275
2276		min_err = err;
2277		*srr = sr - 1;
2278
2279		if (!err)
2280			break;
2281	}
2282
2283	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2284		*srr + 1);
2285	return min_err;
2286}
2287
2288static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2289			unsigned long freq, unsigned int *dlr,
2290			unsigned int *srr)
2291{
2292	int err, min_err = INT_MAX;
2293	unsigned int sr, dl;
2294
2295	if (s->port.type != PORT_HSCIF)
2296		freq *= 2;
2297
2298	for_each_sr(sr, s) {
2299		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2300		dl = clamp(dl, 1U, 65535U);
2301
2302		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2303		if (abs(err) >= abs(min_err))
2304			continue;
2305
2306		min_err = err;
2307		*dlr = dl;
2308		*srr = sr - 1;
2309
2310		if (!err)
2311			break;
2312	}
2313
2314	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2315		min_err, *dlr, *srr + 1);
2316	return min_err;
2317}
2318
2319/* calculate sample rate, BRR, and clock select */
2320static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2321			  unsigned int *brr, unsigned int *srr,
2322			  unsigned int *cks)
2323{
2324	unsigned long freq = s->clk_rates[SCI_FCK];
2325	unsigned int sr, br, prediv, scrate, c;
2326	int err, min_err = INT_MAX;
2327
2328	if (s->port.type != PORT_HSCIF)
2329		freq *= 2;
2330
2331	/*
2332	 * Find the combination of sample rate and clock select with the
2333	 * smallest deviation from the desired baud rate.
2334	 * Prefer high sample rates to maximise the receive margin.
2335	 *
2336	 * M: Receive margin (%)
2337	 * N: Ratio of bit rate to clock (N = sampling rate)
2338	 * D: Clock duty (D = 0 to 1.0)
2339	 * L: Frame length (L = 9 to 12)
2340	 * F: Absolute value of clock frequency deviation
2341	 *
2342	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2343	 *      (|D - 0.5| / N * (1 + F))|
2344	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2345	 */
2346	for_each_sr(sr, s) {
2347		for (c = 0; c <= 3; c++) {
2348			/* integerized formulas from HSCIF documentation */
2349			prediv = sr << (2 * c + 1);
2350
2351			/*
2352			 * We need to calculate:
2353			 *
2354			 *     br = freq / (prediv * bps) clamped to [1..256]
2355			 *     err = freq / (br * prediv) - bps
2356			 *
2357			 * Watch out for overflow when calculating the desired
2358			 * sampling clock rate!
2359			 */
2360			if (bps > UINT_MAX / prediv)
2361				break;
2362
2363			scrate = prediv * bps;
2364			br = DIV_ROUND_CLOSEST(freq, scrate);
2365			br = clamp(br, 1U, 256U);
2366
2367			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2368			if (abs(err) >= abs(min_err))
2369				continue;
2370
2371			min_err = err;
2372			*brr = br - 1;
2373			*srr = sr - 1;
2374			*cks = c;
2375
2376			if (!err)
2377				goto found;
2378		}
2379	}
2380
2381found:
2382	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2383		min_err, *brr, *srr + 1, *cks);
2384	return min_err;
2385}
2386
2387static void sci_reset(struct uart_port *port)
2388{
2389	const struct plat_sci_reg *reg;
2390	unsigned int status;
2391	struct sci_port *s = to_sci_port(port);
2392
2393	serial_port_out(port, SCSCR, s->hscif_tot);	/* TE=0, RE=0, CKE1=0 */
2394
2395	reg = sci_getreg(port, SCFCR);
2396	if (reg->size)
2397		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2398
2399	sci_clear_SCxSR(port,
2400			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2401			SCxSR_BREAK_CLEAR(port));
2402	if (sci_getreg(port, SCLSR)->size) {
2403		status = serial_port_in(port, SCLSR);
2404		status &= ~(SCLSR_TO | SCLSR_ORER);
2405		serial_port_out(port, SCLSR, status);
2406	}
2407
2408	if (s->rx_trigger > 1) {
2409		if (s->rx_fifo_timeout) {
2410			scif_set_rtrg(port, 1);
2411			timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2412		} else {
2413			if (port->type == PORT_SCIFA ||
2414			    port->type == PORT_SCIFB)
2415				scif_set_rtrg(port, 1);
2416			else
2417				scif_set_rtrg(port, s->rx_trigger);
2418		}
2419	}
2420}
2421
2422static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2423		            const struct ktermios *old)
2424{
2425	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2426	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2427	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2428	struct sci_port *s = to_sci_port(port);
2429	const struct plat_sci_reg *reg;
2430	int min_err = INT_MAX, err;
2431	unsigned long max_freq = 0;
2432	int best_clk = -1;
2433	unsigned long flags;
2434
2435	if ((termios->c_cflag & CSIZE) == CS7) {
2436		smr_val |= SCSMR_CHR;
2437	} else {
2438		termios->c_cflag &= ~CSIZE;
2439		termios->c_cflag |= CS8;
2440	}
2441	if (termios->c_cflag & PARENB)
2442		smr_val |= SCSMR_PE;
2443	if (termios->c_cflag & PARODD)
2444		smr_val |= SCSMR_PE | SCSMR_ODD;
2445	if (termios->c_cflag & CSTOPB)
2446		smr_val |= SCSMR_STOP;
2447
2448	/*
2449	 * earlyprintk comes here early on with port->uartclk set to zero.
2450	 * the clock framework is not up and running at this point so here
2451	 * we assume that 115200 is the maximum baud rate. please note that
2452	 * the baud rate is not programmed during earlyprintk - it is assumed
2453	 * that the previous boot loader has enabled required clocks and
2454	 * setup the baud rate generator hardware for us already.
2455	 */
2456	if (!port->uartclk) {
2457		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2458		goto done;
2459	}
2460
2461	for (i = 0; i < SCI_NUM_CLKS; i++)
2462		max_freq = max(max_freq, s->clk_rates[i]);
2463
2464	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2465	if (!baud)
2466		goto done;
2467
2468	/*
2469	 * There can be multiple sources for the sampling clock.  Find the one
2470	 * that gives us the smallest deviation from the desired baud rate.
2471	 */
2472
2473	/* Optional Undivided External Clock */
2474	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2475	    port->type != PORT_SCIFB) {
2476		err = sci_sck_calc(s, baud, &srr1);
2477		if (abs(err) < abs(min_err)) {
2478			best_clk = SCI_SCK;
2479			scr_val = SCSCR_CKE1;
2480			sccks = SCCKS_CKS;
2481			min_err = err;
2482			srr = srr1;
2483			if (!err)
2484				goto done;
2485		}
2486	}
2487
2488	/* Optional BRG Frequency Divided External Clock */
2489	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2490		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2491				   &srr1);
2492		if (abs(err) < abs(min_err)) {
2493			best_clk = SCI_SCIF_CLK;
2494			scr_val = SCSCR_CKE1;
2495			sccks = 0;
2496			min_err = err;
2497			dl = dl1;
2498			srr = srr1;
2499			if (!err)
2500				goto done;
2501		}
2502	}
2503
2504	/* Optional BRG Frequency Divided Internal Clock */
2505	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2506		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2507				   &srr1);
2508		if (abs(err) < abs(min_err)) {
2509			best_clk = SCI_BRG_INT;
2510			scr_val = SCSCR_CKE1;
2511			sccks = SCCKS_XIN;
2512			min_err = err;
2513			dl = dl1;
2514			srr = srr1;
2515			if (!min_err)
2516				goto done;
2517		}
2518	}
2519
2520	/* Divided Functional Clock using standard Bit Rate Register */
2521	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2522	if (abs(err) < abs(min_err)) {
2523		best_clk = SCI_FCK;
2524		scr_val = 0;
2525		min_err = err;
2526		brr = brr1;
2527		srr = srr1;
2528		cks = cks1;
2529	}
2530
2531done:
2532	if (best_clk >= 0)
2533		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2534			s->clks[best_clk], baud, min_err);
2535
2536	sci_port_enable(s);
2537
2538	/*
2539	 * Program the optional External Baud Rate Generator (BRG) first.
2540	 * It controls the mux to select (H)SCK or frequency divided clock.
2541	 */
2542	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2543		serial_port_out(port, SCDL, dl);
2544		serial_port_out(port, SCCKS, sccks);
2545	}
2546
2547	uart_port_lock_irqsave(port, &flags);
2548
2549	sci_reset(port);
2550
2551	uart_update_timeout(port, termios->c_cflag, baud);
2552
2553	/* byte size and parity */
2554	bits = tty_get_frame_size(termios->c_cflag);
2555
2556	if (sci_getreg(port, SEMR)->size)
2557		serial_port_out(port, SEMR, 0);
2558
2559	if (best_clk >= 0) {
2560		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2561			switch (srr + 1) {
2562			case 5:  smr_val |= SCSMR_SRC_5;  break;
2563			case 7:  smr_val |= SCSMR_SRC_7;  break;
2564			case 11: smr_val |= SCSMR_SRC_11; break;
2565			case 13: smr_val |= SCSMR_SRC_13; break;
2566			case 16: smr_val |= SCSMR_SRC_16; break;
2567			case 17: smr_val |= SCSMR_SRC_17; break;
2568			case 19: smr_val |= SCSMR_SRC_19; break;
2569			case 27: smr_val |= SCSMR_SRC_27; break;
2570			}
2571		smr_val |= cks;
2572		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2573		serial_port_out(port, SCSMR, smr_val);
2574		serial_port_out(port, SCBRR, brr);
2575		if (sci_getreg(port, HSSRR)->size) {
2576			unsigned int hssrr = srr | HSCIF_SRE;
2577			/* Calculate deviation from intended rate at the
2578			 * center of the last stop bit in sampling clocks.
2579			 */
2580			int last_stop = bits * 2 - 1;
2581			int deviation = DIV_ROUND_CLOSEST(min_err * last_stop *
2582							  (int)(srr + 1),
2583							  2 * (int)baud);
2584
2585			if (abs(deviation) >= 2) {
2586				/* At least two sampling clocks off at the
2587				 * last stop bit; we can increase the error
2588				 * margin by shifting the sampling point.
2589				 */
2590				int shift = clamp(deviation / 2, -8, 7);
2591
2592				hssrr |= (shift << HSCIF_SRHP_SHIFT) &
2593					 HSCIF_SRHP_MASK;
2594				hssrr |= HSCIF_SRDE;
2595			}
2596			serial_port_out(port, HSSRR, hssrr);
2597		}
2598
2599		/* Wait one bit interval */
2600		udelay((1000000 + (baud - 1)) / baud);
2601	} else {
2602		/* Don't touch the bit rate configuration */
2603		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2604		smr_val |= serial_port_in(port, SCSMR) &
2605			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2606		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2607		serial_port_out(port, SCSMR, smr_val);
2608	}
2609
2610	sci_init_pins(port, termios->c_cflag);
2611
2612	port->status &= ~UPSTAT_AUTOCTS;
2613	s->autorts = false;
2614	reg = sci_getreg(port, SCFCR);
2615	if (reg->size) {
2616		unsigned short ctrl = serial_port_in(port, SCFCR);
2617
2618		if ((port->flags & UPF_HARD_FLOW) &&
2619		    (termios->c_cflag & CRTSCTS)) {
2620			/* There is no CTS interrupt to restart the hardware */
2621			port->status |= UPSTAT_AUTOCTS;
2622			/* MCE is enabled when RTS is raised */
2623			s->autorts = true;
2624		}
2625
2626		/*
2627		 * As we've done a sci_reset() above, ensure we don't
2628		 * interfere with the FIFOs while toggling MCE. As the
2629		 * reset values could still be set, simply mask them out.
2630		 */
2631		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2632
2633		serial_port_out(port, SCFCR, ctrl);
2634	}
2635	if (port->flags & UPF_HARD_FLOW) {
2636		/* Refresh (Auto) RTS */
2637		sci_set_mctrl(port, port->mctrl);
2638	}
2639
2640	/*
2641	 * For SCI, TE (transmit enable) must be set after setting TIE
2642	 * (transmit interrupt enable) or in the same instruction to
2643	 * start the transmitting process. So skip setting TE here for SCI.
2644	 */
2645	if (port->type != PORT_SCI)
2646		scr_val |= SCSCR_TE;
2647	scr_val |= SCSCR_RE | (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2648	serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2649	if ((srr + 1 == 5) &&
2650	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2651		/*
2652		 * In asynchronous mode, when the sampling rate is 1/5, first
2653		 * received data may become invalid on some SCIFA and SCIFB.
2654		 * To avoid this problem wait more than 1 serial data time (1
2655		 * bit time x serial data number) after setting SCSCR.RE = 1.
2656		 */
2657		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2658	}
2659
2660	/* Calculate delay for 2 DMA buffers (4 FIFO). */
2661	s->rx_frame = (10000 * bits) / (baud / 100);
2662#ifdef CONFIG_SERIAL_SH_SCI_DMA
2663	s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2664#endif
2665
2666	if ((termios->c_cflag & CREAD) != 0)
2667		sci_start_rx(port);
2668
2669	uart_port_unlock_irqrestore(port, flags);
2670
2671	sci_port_disable(s);
2672
2673	if (UART_ENABLE_MS(port, termios->c_cflag))
2674		sci_enable_ms(port);
2675}
2676
2677static void sci_pm(struct uart_port *port, unsigned int state,
2678		   unsigned int oldstate)
2679{
2680	struct sci_port *sci_port = to_sci_port(port);
2681
2682	switch (state) {
2683	case UART_PM_STATE_OFF:
2684		sci_port_disable(sci_port);
2685		break;
2686	default:
2687		sci_port_enable(sci_port);
2688		break;
2689	}
2690}
2691
2692static const char *sci_type(struct uart_port *port)
2693{
2694	switch (port->type) {
2695	case PORT_IRDA:
2696		return "irda";
2697	case PORT_SCI:
2698		return "sci";
2699	case PORT_SCIF:
2700		return "scif";
2701	case PORT_SCIFA:
2702		return "scifa";
2703	case PORT_SCIFB:
2704		return "scifb";
2705	case PORT_HSCIF:
2706		return "hscif";
2707	}
2708
2709	return NULL;
2710}
2711
2712static int sci_remap_port(struct uart_port *port)
2713{
2714	struct sci_port *sport = to_sci_port(port);
2715
2716	/*
2717	 * Nothing to do if there's already an established membase.
2718	 */
2719	if (port->membase)
2720		return 0;
2721
2722	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2723		port->membase = ioremap(port->mapbase, sport->reg_size);
2724		if (unlikely(!port->membase)) {
2725			dev_err(port->dev, "can't remap port#%d\n", port->line);
2726			return -ENXIO;
2727		}
2728	} else {
2729		/*
2730		 * For the simple (and majority of) cases where we don't
2731		 * need to do any remapping, just cast the cookie
2732		 * directly.
2733		 */
2734		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2735	}
2736
2737	return 0;
2738}
2739
2740static void sci_release_port(struct uart_port *port)
2741{
2742	struct sci_port *sport = to_sci_port(port);
2743
2744	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2745		iounmap(port->membase);
2746		port->membase = NULL;
2747	}
2748
2749	release_mem_region(port->mapbase, sport->reg_size);
2750}
2751
2752static int sci_request_port(struct uart_port *port)
2753{
2754	struct resource *res;
2755	struct sci_port *sport = to_sci_port(port);
2756	int ret;
2757
2758	res = request_mem_region(port->mapbase, sport->reg_size,
2759				 dev_name(port->dev));
2760	if (unlikely(res == NULL)) {
2761		dev_err(port->dev, "request_mem_region failed.");
2762		return -EBUSY;
2763	}
2764
2765	ret = sci_remap_port(port);
2766	if (unlikely(ret != 0)) {
2767		release_resource(res);
2768		return ret;
2769	}
2770
2771	return 0;
2772}
2773
2774static void sci_config_port(struct uart_port *port, int flags)
2775{
2776	if (flags & UART_CONFIG_TYPE) {
2777		struct sci_port *sport = to_sci_port(port);
2778
2779		port->type = sport->cfg->type;
2780		sci_request_port(port);
2781	}
2782}
2783
2784static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2785{
2786	if (ser->baud_base < 2400)
2787		/* No paper tape reader for Mitch.. */
2788		return -EINVAL;
2789
2790	return 0;
2791}
2792
2793static const struct uart_ops sci_uart_ops = {
2794	.tx_empty	= sci_tx_empty,
2795	.set_mctrl	= sci_set_mctrl,
2796	.get_mctrl	= sci_get_mctrl,
2797	.start_tx	= sci_start_tx,
2798	.stop_tx	= sci_stop_tx,
2799	.stop_rx	= sci_stop_rx,
2800	.enable_ms	= sci_enable_ms,
2801	.break_ctl	= sci_break_ctl,
2802	.startup	= sci_startup,
2803	.shutdown	= sci_shutdown,
2804	.flush_buffer	= sci_flush_buffer,
2805	.set_termios	= sci_set_termios,
2806	.pm		= sci_pm,
2807	.type		= sci_type,
2808	.release_port	= sci_release_port,
2809	.request_port	= sci_request_port,
2810	.config_port	= sci_config_port,
2811	.verify_port	= sci_verify_port,
2812#ifdef CONFIG_CONSOLE_POLL
2813	.poll_get_char	= sci_poll_get_char,
2814	.poll_put_char	= sci_poll_put_char,
2815#endif
2816};
2817
2818static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2819{
2820	const char *clk_names[] = {
2821		[SCI_FCK] = "fck",
2822		[SCI_SCK] = "sck",
2823		[SCI_BRG_INT] = "brg_int",
2824		[SCI_SCIF_CLK] = "scif_clk",
2825	};
2826	struct clk *clk;
2827	unsigned int i;
2828
2829	if (sci_port->cfg->type == PORT_HSCIF)
2830		clk_names[SCI_SCK] = "hsck";
2831
2832	for (i = 0; i < SCI_NUM_CLKS; i++) {
2833		clk = devm_clk_get_optional(dev, clk_names[i]);
2834		if (IS_ERR(clk))
2835			return PTR_ERR(clk);
 
 
 
 
 
 
 
 
 
 
 
 
2836
2837		if (!clk && i == SCI_FCK) {
2838			/*
2839			 * Not all SH platforms declare a clock lookup entry
2840			 * for SCI devices, in which case we need to get the
2841			 * global "peripheral_clk" clock.
2842			 */
2843			clk = devm_clk_get(dev, "peripheral_clk");
2844			if (IS_ERR(clk))
2845				return dev_err_probe(dev, PTR_ERR(clk),
2846						     "failed to get %s\n",
2847						     clk_names[i]);
 
 
2848		}
2849
2850		if (!clk)
2851			dev_dbg(dev, "failed to get %s\n", clk_names[i]);
 
 
2852		else
2853			dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
2854				clk, clk_get_rate(clk));
2855		sci_port->clks[i] = clk;
2856	}
2857	return 0;
2858}
2859
2860static const struct sci_port_params *
2861sci_probe_regmap(const struct plat_sci_port *cfg)
2862{
2863	unsigned int regtype;
2864
2865	if (cfg->regtype != SCIx_PROBE_REGTYPE)
2866		return &sci_port_params[cfg->regtype];
2867
2868	switch (cfg->type) {
2869	case PORT_SCI:
2870		regtype = SCIx_SCI_REGTYPE;
2871		break;
2872	case PORT_IRDA:
2873		regtype = SCIx_IRDA_REGTYPE;
2874		break;
2875	case PORT_SCIFA:
2876		regtype = SCIx_SCIFA_REGTYPE;
2877		break;
2878	case PORT_SCIFB:
2879		regtype = SCIx_SCIFB_REGTYPE;
2880		break;
2881	case PORT_SCIF:
2882		/*
2883		 * The SH-4 is a bit of a misnomer here, although that's
2884		 * where this particular port layout originated. This
2885		 * configuration (or some slight variation thereof)
2886		 * remains the dominant model for all SCIFs.
2887		 */
2888		regtype = SCIx_SH4_SCIF_REGTYPE;
2889		break;
2890	case PORT_HSCIF:
2891		regtype = SCIx_HSCIF_REGTYPE;
2892		break;
2893	default:
2894		pr_err("Can't probe register map for given port\n");
2895		return NULL;
2896	}
2897
2898	return &sci_port_params[regtype];
2899}
2900
2901static int sci_init_single(struct platform_device *dev,
2902			   struct sci_port *sci_port, unsigned int index,
2903			   const struct plat_sci_port *p, bool early)
2904{
2905	struct uart_port *port = &sci_port->port;
2906	const struct resource *res;
2907	unsigned int i;
2908	int ret;
2909
2910	sci_port->cfg	= p;
2911
2912	port->ops	= &sci_uart_ops;
2913	port->iotype	= UPIO_MEM;
2914	port->line	= index;
2915	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_SH_SCI_CONSOLE);
2916
2917	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2918	if (res == NULL)
2919		return -ENOMEM;
2920
2921	port->mapbase = res->start;
2922	sci_port->reg_size = resource_size(res);
2923
2924	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) {
2925		if (i)
2926			sci_port->irqs[i] = platform_get_irq_optional(dev, i);
2927		else
2928			sci_port->irqs[i] = platform_get_irq(dev, i);
2929	}
2930
2931	/*
2932	 * The fourth interrupt on SCI port is transmit end interrupt, so
2933	 * shuffle the interrupts.
2934	 */
2935	if (p->type == PORT_SCI)
2936		swap(sci_port->irqs[SCIx_BRI_IRQ], sci_port->irqs[SCIx_TEI_IRQ]);
2937
2938	/* The SCI generates several interrupts. They can be muxed together or
2939	 * connected to different interrupt lines. In the muxed case only one
2940	 * interrupt resource is specified as there is only one interrupt ID.
2941	 * In the non-muxed case, up to 6 interrupt signals might be generated
2942	 * from the SCI, however those signals might have their own individual
2943	 * interrupt ID numbers, or muxed together with another interrupt.
2944	 */
2945	if (sci_port->irqs[0] < 0)
2946		return -ENXIO;
2947
2948	if (sci_port->irqs[1] < 0)
2949		for (i = 1; i < ARRAY_SIZE(sci_port->irqs); i++)
2950			sci_port->irqs[i] = sci_port->irqs[0];
2951
2952	sci_port->params = sci_probe_regmap(p);
2953	if (unlikely(sci_port->params == NULL))
2954		return -EINVAL;
2955
2956	switch (p->type) {
2957	case PORT_SCIFB:
2958		sci_port->rx_trigger = 48;
2959		break;
2960	case PORT_HSCIF:
2961		sci_port->rx_trigger = 64;
2962		break;
2963	case PORT_SCIFA:
2964		sci_port->rx_trigger = 32;
2965		break;
2966	case PORT_SCIF:
2967		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2968			/* RX triggering not implemented for this IP */
2969			sci_port->rx_trigger = 1;
2970		else
2971			sci_port->rx_trigger = 8;
2972		break;
2973	default:
2974		sci_port->rx_trigger = 1;
2975		break;
2976	}
2977
2978	sci_port->rx_fifo_timeout = 0;
2979	sci_port->hscif_tot = 0;
2980
2981	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2982	 * match the SoC datasheet, this should be investigated. Let platform
2983	 * data override the sampling rate for now.
2984	 */
2985	sci_port->sampling_rate_mask = p->sampling_rate
2986				     ? SCI_SR(p->sampling_rate)
2987				     : sci_port->params->sampling_rate_mask;
2988
2989	if (!early) {
2990		ret = sci_init_clocks(sci_port, &dev->dev);
2991		if (ret < 0)
2992			return ret;
2993
2994		port->dev = &dev->dev;
2995
2996		pm_runtime_enable(&dev->dev);
2997	}
2998
2999	port->type		= p->type;
3000	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
3001	port->fifosize		= sci_port->params->fifosize;
3002
3003	if (port->type == PORT_SCI && !dev->dev.of_node) {
3004		if (sci_port->reg_size >= 0x20)
3005			port->regshift = 2;
3006		else
3007			port->regshift = 1;
3008	}
3009
3010	/*
3011	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
3012	 * for the multi-IRQ ports, which is where we are primarily
3013	 * concerned with the shutdown path synchronization.
3014	 *
3015	 * For the muxed case there's nothing more to do.
3016	 */
3017	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
3018	port->irqflags		= 0;
3019
3020	port->serial_in		= sci_serial_in;
3021	port->serial_out	= sci_serial_out;
3022
3023	return 0;
3024}
3025
3026static void sci_cleanup_single(struct sci_port *port)
3027{
3028	pm_runtime_disable(port->port.dev);
3029}
3030
3031#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
3032    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
3033static void serial_console_putchar(struct uart_port *port, unsigned char ch)
3034{
3035	sci_poll_put_char(port, ch);
3036}
3037
3038/*
3039 *	Print a string to the serial port trying not to disturb
3040 *	any possible real use of the port...
3041 */
3042static void serial_console_write(struct console *co, const char *s,
3043				 unsigned count)
3044{
3045	struct sci_port *sci_port = &sci_ports[co->index];
3046	struct uart_port *port = &sci_port->port;
3047	unsigned short bits, ctrl, ctrl_temp;
3048	unsigned long flags;
3049	int locked = 1;
3050
3051	if (port->sysrq)
3052		locked = 0;
3053	else if (oops_in_progress)
3054		locked = uart_port_trylock_irqsave(port, &flags);
3055	else
3056		uart_port_lock_irqsave(port, &flags);
3057
3058	/* first save SCSCR then disable interrupts, keep clock source */
3059	ctrl = serial_port_in(port, SCSCR);
3060	ctrl_temp = SCSCR_RE | SCSCR_TE |
3061		    (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
3062		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
3063	serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
3064
3065	uart_console_write(port, s, count, serial_console_putchar);
3066
3067	/* wait until fifo is empty and last bit has been transmitted */
3068	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
3069	while ((serial_port_in(port, SCxSR) & bits) != bits)
3070		cpu_relax();
3071
3072	/* restore the SCSCR */
3073	serial_port_out(port, SCSCR, ctrl);
3074
3075	if (locked)
3076		uart_port_unlock_irqrestore(port, flags);
3077}
3078
3079static int serial_console_setup(struct console *co, char *options)
3080{
3081	struct sci_port *sci_port;
3082	struct uart_port *port;
3083	int baud = 115200;
3084	int bits = 8;
3085	int parity = 'n';
3086	int flow = 'n';
3087	int ret;
3088
3089	/*
3090	 * Refuse to handle any bogus ports.
3091	 */
3092	if (co->index < 0 || co->index >= SCI_NPORTS)
3093		return -ENODEV;
3094
3095	sci_port = &sci_ports[co->index];
3096	port = &sci_port->port;
3097
3098	/*
3099	 * Refuse to handle uninitialized ports.
3100	 */
3101	if (!port->ops)
3102		return -ENODEV;
3103
3104	ret = sci_remap_port(port);
3105	if (unlikely(ret != 0))
3106		return ret;
3107
3108	if (options)
3109		uart_parse_options(options, &baud, &parity, &bits, &flow);
3110
3111	return uart_set_options(port, co, baud, parity, bits, flow);
3112}
3113
3114static struct console serial_console = {
3115	.name		= "ttySC",
3116	.device		= uart_console_device,
3117	.write		= serial_console_write,
3118	.setup		= serial_console_setup,
3119	.flags		= CON_PRINTBUFFER,
3120	.index		= -1,
3121	.data		= &sci_uart_driver,
3122};
3123
3124#ifdef CONFIG_SUPERH
3125static char early_serial_buf[32];
3126
3127static int early_serial_console_setup(struct console *co, char *options)
3128{
3129	/*
3130	 * This early console is always registered using the earlyprintk=
3131	 * parameter, which does not call add_preferred_console(). Thus
3132	 * @options is always NULL and the options for this early console
3133	 * are passed using a custom buffer.
3134	 */
3135	WARN_ON(options);
3136
3137	return serial_console_setup(co, early_serial_buf);
3138}
3139
3140static struct console early_serial_console = {
3141	.name           = "early_ttySC",
3142	.write          = serial_console_write,
3143	.setup		= early_serial_console_setup,
3144	.flags          = CON_PRINTBUFFER,
3145	.index		= -1,
3146};
3147
 
 
3148static int sci_probe_earlyprintk(struct platform_device *pdev)
3149{
3150	const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
3151
3152	if (early_serial_console.data)
3153		return -EEXIST;
3154
3155	early_serial_console.index = pdev->id;
3156
3157	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
3158
 
 
3159	if (!strstr(early_serial_buf, "keep"))
3160		early_serial_console.flags |= CON_BOOT;
3161
3162	register_console(&early_serial_console);
3163	return 0;
3164}
3165#endif
3166
3167#define SCI_CONSOLE	(&serial_console)
3168
3169#else
3170static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3171{
3172	return -EINVAL;
3173}
3174
3175#define SCI_CONSOLE	NULL
3176
3177#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3178
3179static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3180
3181static DEFINE_MUTEX(sci_uart_registration_lock);
3182static struct uart_driver sci_uart_driver = {
3183	.owner		= THIS_MODULE,
3184	.driver_name	= "sci",
3185	.dev_name	= "ttySC",
3186	.major		= SCI_MAJOR,
3187	.minor		= SCI_MINOR_START,
3188	.nr		= SCI_NPORTS,
3189	.cons		= SCI_CONSOLE,
3190};
3191
3192static void sci_remove(struct platform_device *dev)
3193{
3194	struct sci_port *port = platform_get_drvdata(dev);
3195	unsigned int type = port->port.type;	/* uart_remove_... clears it */
3196
3197	sci_ports_in_use &= ~BIT(port->port.line);
3198	uart_remove_one_port(&sci_uart_driver, &port->port);
3199
3200	sci_cleanup_single(port);
3201
3202	if (port->port.fifosize > 1)
3203		device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3204	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
3205		device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
 
 
3206}
3207
3208
3209#define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
3210#define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
3211#define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
3212
3213static const struct of_device_id of_sci_match[] __maybe_unused = {
3214	/* SoC-specific types */
3215	{
3216		.compatible = "renesas,scif-r7s72100",
3217		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3218	},
3219	{
3220		.compatible = "renesas,scif-r7s9210",
3221		.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3222	},
3223	{
3224		.compatible = "renesas,scif-r9a07g044",
3225		.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3226	},
3227	/* Family-specific types */
3228	{
3229		.compatible = "renesas,rcar-gen1-scif",
3230		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3231	}, {
3232		.compatible = "renesas,rcar-gen2-scif",
3233		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3234	}, {
3235		.compatible = "renesas,rcar-gen3-scif",
3236		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3237	}, {
3238		.compatible = "renesas,rcar-gen4-scif",
3239		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3240	},
3241	/* Generic types */
3242	{
3243		.compatible = "renesas,scif",
3244		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3245	}, {
3246		.compatible = "renesas,scifa",
3247		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3248	}, {
3249		.compatible = "renesas,scifb",
3250		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3251	}, {
3252		.compatible = "renesas,hscif",
3253		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3254	}, {
3255		.compatible = "renesas,sci",
3256		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3257	}, {
3258		/* Terminator */
3259	},
3260};
3261MODULE_DEVICE_TABLE(of, of_sci_match);
3262
3263static void sci_reset_control_assert(void *data)
3264{
3265	reset_control_assert(data);
3266}
3267
3268static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3269					  unsigned int *dev_id)
3270{
3271	struct device_node *np = pdev->dev.of_node;
3272	struct reset_control *rstc;
3273	struct plat_sci_port *p;
3274	struct sci_port *sp;
3275	const void *data;
3276	int id, ret;
3277
3278	if (!IS_ENABLED(CONFIG_OF) || !np)
3279		return ERR_PTR(-EINVAL);
3280
3281	data = of_device_get_match_data(&pdev->dev);
3282
3283	rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
3284	if (IS_ERR(rstc))
3285		return ERR_PTR(dev_err_probe(&pdev->dev, PTR_ERR(rstc),
3286					     "failed to get reset ctrl\n"));
3287
3288	ret = reset_control_deassert(rstc);
3289	if (ret) {
3290		dev_err(&pdev->dev, "failed to deassert reset %d\n", ret);
3291		return ERR_PTR(ret);
3292	}
3293
3294	ret = devm_add_action_or_reset(&pdev->dev, sci_reset_control_assert, rstc);
3295	if (ret) {
3296		dev_err(&pdev->dev, "failed to register assert devm action, %d\n",
3297			ret);
3298		return ERR_PTR(ret);
3299	}
3300
3301	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3302	if (!p)
3303		return ERR_PTR(-ENOMEM);
3304
3305	/* Get the line number from the aliases node. */
3306	id = of_alias_get_id(np, "serial");
3307	if (id < 0 && ~sci_ports_in_use)
3308		id = ffz(sci_ports_in_use);
3309	if (id < 0) {
3310		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3311		return ERR_PTR(-EINVAL);
3312	}
3313	if (id >= ARRAY_SIZE(sci_ports)) {
3314		dev_err(&pdev->dev, "serial%d out of range\n", id);
3315		return ERR_PTR(-EINVAL);
3316	}
3317
3318	sp = &sci_ports[id];
3319	*dev_id = id;
3320
3321	p->type = SCI_OF_TYPE(data);
3322	p->regtype = SCI_OF_REGTYPE(data);
3323
3324	sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3325
3326	return p;
3327}
3328
3329static int sci_probe_single(struct platform_device *dev,
3330				      unsigned int index,
3331				      struct plat_sci_port *p,
3332				      struct sci_port *sciport)
3333{
3334	int ret;
3335
3336	/* Sanity check */
3337	if (unlikely(index >= SCI_NPORTS)) {
3338		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3339			   index+1, SCI_NPORTS);
3340		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3341		return -EINVAL;
3342	}
3343	BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
3344	if (sci_ports_in_use & BIT(index))
3345		return -EBUSY;
3346
3347	mutex_lock(&sci_uart_registration_lock);
3348	if (!sci_uart_driver.state) {
3349		ret = uart_register_driver(&sci_uart_driver);
3350		if (ret) {
3351			mutex_unlock(&sci_uart_registration_lock);
3352			return ret;
3353		}
3354	}
3355	mutex_unlock(&sci_uart_registration_lock);
3356
3357	ret = sci_init_single(dev, sciport, index, p, false);
3358	if (ret)
3359		return ret;
3360
3361	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3362	if (IS_ERR(sciport->gpios))
3363		return PTR_ERR(sciport->gpios);
3364
3365	if (sciport->has_rtscts) {
3366		if (mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_CTS) ||
3367		    mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_RTS)) {
3368			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3369			return -EINVAL;
3370		}
3371		sciport->port.flags |= UPF_HARD_FLOW;
3372	}
3373
3374	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3375	if (ret) {
3376		sci_cleanup_single(sciport);
3377		return ret;
3378	}
3379
3380	return 0;
3381}
3382
3383static int sci_probe(struct platform_device *dev)
3384{
3385	struct plat_sci_port *p;
3386	struct sci_port *sp;
3387	unsigned int dev_id;
3388	int ret;
3389
3390	/*
3391	 * If we've come here via earlyprintk initialization, head off to
3392	 * the special early probe. We don't have sufficient device state
3393	 * to make it beyond this yet.
3394	 */
3395#ifdef CONFIG_SUPERH
3396	if (is_sh_early_platform_device(dev))
3397		return sci_probe_earlyprintk(dev);
3398#endif
3399
3400	if (dev->dev.of_node) {
3401		p = sci_parse_dt(dev, &dev_id);
3402		if (IS_ERR(p))
3403			return PTR_ERR(p);
3404	} else {
3405		p = dev->dev.platform_data;
3406		if (p == NULL) {
3407			dev_err(&dev->dev, "no platform data supplied\n");
3408			return -EINVAL;
3409		}
3410
3411		dev_id = dev->id;
3412	}
3413
3414	sp = &sci_ports[dev_id];
3415	platform_set_drvdata(dev, sp);
3416
3417	ret = sci_probe_single(dev, dev_id, p, sp);
3418	if (ret)
3419		return ret;
3420
3421	if (sp->port.fifosize > 1) {
3422		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3423		if (ret)
3424			return ret;
3425	}
3426	if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3427	    sp->port.type == PORT_HSCIF) {
3428		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
3429		if (ret) {
3430			if (sp->port.fifosize > 1) {
3431				device_remove_file(&dev->dev,
3432						   &dev_attr_rx_fifo_trigger);
3433			}
3434			return ret;
3435		}
3436	}
3437
3438#ifdef CONFIG_SH_STANDARD_BIOS
3439	sh_bios_gdb_detach();
3440#endif
3441
3442	sci_ports_in_use |= BIT(dev_id);
3443	return 0;
3444}
3445
3446static __maybe_unused int sci_suspend(struct device *dev)
3447{
3448	struct sci_port *sport = dev_get_drvdata(dev);
3449
3450	if (sport)
3451		uart_suspend_port(&sci_uart_driver, &sport->port);
3452
3453	return 0;
3454}
3455
3456static __maybe_unused int sci_resume(struct device *dev)
3457{
3458	struct sci_port *sport = dev_get_drvdata(dev);
3459
3460	if (sport)
3461		uart_resume_port(&sci_uart_driver, &sport->port);
3462
3463	return 0;
3464}
3465
3466static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3467
3468static struct platform_driver sci_driver = {
3469	.probe		= sci_probe,
3470	.remove_new	= sci_remove,
3471	.driver		= {
3472		.name	= "sh-sci",
3473		.pm	= &sci_dev_pm_ops,
3474		.of_match_table = of_match_ptr(of_sci_match),
3475	},
3476};
3477
3478static int __init sci_init(void)
3479{
3480	pr_info("%s\n", banner);
3481
3482	return platform_driver_register(&sci_driver);
3483}
3484
3485static void __exit sci_exit(void)
3486{
3487	platform_driver_unregister(&sci_driver);
3488
3489	if (sci_uart_driver.state)
3490		uart_unregister_driver(&sci_uart_driver);
3491}
3492
3493#if defined(CONFIG_SUPERH) && defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
3494sh_early_platform_init_buffer("earlyprintk", &sci_driver,
3495			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3496#endif
3497#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3498static struct plat_sci_port port_cfg __initdata;
3499
3500static int __init early_console_setup(struct earlycon_device *device,
3501				      int type)
3502{
3503	if (!device->port.membase)
3504		return -ENODEV;
3505
3506	device->port.serial_in = sci_serial_in;
3507	device->port.serial_out	= sci_serial_out;
3508	device->port.type = type;
3509	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3510	port_cfg.type = type;
3511	sci_ports[0].cfg = &port_cfg;
3512	sci_ports[0].params = sci_probe_regmap(&port_cfg);
3513	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3514	sci_serial_out(&sci_ports[0].port, SCSCR,
3515		       SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3516
3517	device->con->write = serial_console_write;
3518	return 0;
3519}
3520static int __init sci_early_console_setup(struct earlycon_device *device,
3521					  const char *opt)
3522{
3523	return early_console_setup(device, PORT_SCI);
3524}
3525static int __init scif_early_console_setup(struct earlycon_device *device,
3526					  const char *opt)
3527{
3528	return early_console_setup(device, PORT_SCIF);
3529}
3530static int __init rzscifa_early_console_setup(struct earlycon_device *device,
3531					  const char *opt)
3532{
3533	port_cfg.regtype = SCIx_RZ_SCIFA_REGTYPE;
3534	return early_console_setup(device, PORT_SCIF);
3535}
3536
3537static int __init scifa_early_console_setup(struct earlycon_device *device,
3538					  const char *opt)
3539{
3540	return early_console_setup(device, PORT_SCIFA);
3541}
3542static int __init scifb_early_console_setup(struct earlycon_device *device,
3543					  const char *opt)
3544{
3545	return early_console_setup(device, PORT_SCIFB);
3546}
3547static int __init hscif_early_console_setup(struct earlycon_device *device,
3548					  const char *opt)
3549{
3550	return early_console_setup(device, PORT_HSCIF);
3551}
3552
3553OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3554OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3555OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rzscifa_early_console_setup);
3556OF_EARLYCON_DECLARE(scif, "renesas,scif-r9a07g044", rzscifa_early_console_setup);
3557OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3558OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3559OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3560#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3561
3562module_init(sci_init);
3563module_exit(sci_exit);
3564
3565MODULE_LICENSE("GPL");
3566MODULE_ALIAS("platform:sh-sci");
3567MODULE_AUTHOR("Paul Mundt");
3568MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * SuperH on-chip serial module support.  (SCI with no FIFO / with FIFO)
   4 *
   5 *  Copyright (C) 2002 - 2011  Paul Mundt
   6 *  Copyright (C) 2015 Glider bvba
   7 *  Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
   8 *
   9 * based off of the old drivers/char/sh-sci.c by:
  10 *
  11 *   Copyright (C) 1999, 2000  Niibe Yutaka
  12 *   Copyright (C) 2000  Sugioka Toshinobu
  13 *   Modified to support multiple serial ports. Stuart Menefy (May 2000).
  14 *   Modified to support SecureEdge. David McCullough (2002)
  15 *   Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
  16 *   Removed SH7300 support (Jul 2007).
  17 */
  18#undef DEBUG
  19
  20#include <linux/clk.h>
  21#include <linux/console.h>
  22#include <linux/ctype.h>
  23#include <linux/cpufreq.h>
  24#include <linux/delay.h>
  25#include <linux/dmaengine.h>
  26#include <linux/dma-mapping.h>
  27#include <linux/err.h>
  28#include <linux/errno.h>
  29#include <linux/init.h>
  30#include <linux/interrupt.h>
  31#include <linux/ioport.h>
  32#include <linux/ktime.h>
  33#include <linux/major.h>
 
  34#include <linux/module.h>
  35#include <linux/mm.h>
  36#include <linux/of.h>
  37#include <linux/of_device.h>
  38#include <linux/platform_device.h>
  39#include <linux/pm_runtime.h>
 
  40#include <linux/scatterlist.h>
  41#include <linux/serial.h>
  42#include <linux/serial_sci.h>
  43#include <linux/sh_dma.h>
  44#include <linux/slab.h>
  45#include <linux/string.h>
  46#include <linux/sysrq.h>
  47#include <linux/timer.h>
  48#include <linux/tty.h>
  49#include <linux/tty_flip.h>
  50
  51#ifdef CONFIG_SUPERH
  52#include <asm/sh_bios.h>
  53#include <asm/platform_early.h>
  54#endif
  55
  56#include "serial_mctrl_gpio.h"
  57#include "sh-sci.h"
  58
  59/* Offsets into the sci_port->irqs array */
  60enum {
  61	SCIx_ERI_IRQ,
  62	SCIx_RXI_IRQ,
  63	SCIx_TXI_IRQ,
  64	SCIx_BRI_IRQ,
  65	SCIx_DRI_IRQ,
  66	SCIx_TEI_IRQ,
  67	SCIx_NR_IRQS,
  68
  69	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
  70};
  71
  72#define SCIx_IRQ_IS_MUXED(port)			\
  73	((port)->irqs[SCIx_ERI_IRQ] ==	\
  74	 (port)->irqs[SCIx_RXI_IRQ]) ||	\
  75	((port)->irqs[SCIx_ERI_IRQ] &&	\
  76	 ((port)->irqs[SCIx_RXI_IRQ] < 0))
  77
  78enum SCI_CLKS {
  79	SCI_FCK,		/* Functional Clock */
  80	SCI_SCK,		/* Optional External Clock */
  81	SCI_BRG_INT,		/* Optional BRG Internal Clock Source */
  82	SCI_SCIF_CLK,		/* Optional BRG External Clock Source */
  83	SCI_NUM_CLKS
  84};
  85
  86/* Bit x set means sampling rate x + 1 is supported */
  87#define SCI_SR(x)		BIT((x) - 1)
  88#define SCI_SR_RANGE(x, y)	GENMASK((y) - 1, (x) - 1)
  89
  90#define SCI_SR_SCIFAB		SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
  91				SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
  92				SCI_SR(19) | SCI_SR(27)
  93
  94#define min_sr(_port)		ffs((_port)->sampling_rate_mask)
  95#define max_sr(_port)		fls((_port)->sampling_rate_mask)
  96
  97/* Iterate over all supported sampling rates, from high to low */
  98#define for_each_sr(_sr, _port)						\
  99	for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--)	\
 100		if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
 101
 102struct plat_sci_reg {
 103	u8 offset, size;
 104};
 105
 106struct sci_port_params {
 107	const struct plat_sci_reg regs[SCIx_NR_REGS];
 108	unsigned int fifosize;
 109	unsigned int overrun_reg;
 110	unsigned int overrun_mask;
 111	unsigned int sampling_rate_mask;
 112	unsigned int error_mask;
 113	unsigned int error_clear;
 114};
 115
 116struct sci_port {
 117	struct uart_port	port;
 118
 119	/* Platform configuration */
 120	const struct sci_port_params *params;
 121	const struct plat_sci_port *cfg;
 122	unsigned int		sampling_rate_mask;
 123	resource_size_t		reg_size;
 124	struct mctrl_gpios	*gpios;
 125
 126	/* Clocks */
 127	struct clk		*clks[SCI_NUM_CLKS];
 128	unsigned long		clk_rates[SCI_NUM_CLKS];
 129
 130	int			irqs[SCIx_NR_IRQS];
 131	char			*irqstr[SCIx_NR_IRQS];
 132
 133	struct dma_chan			*chan_tx;
 134	struct dma_chan			*chan_rx;
 135
 136#ifdef CONFIG_SERIAL_SH_SCI_DMA
 137	struct dma_chan			*chan_tx_saved;
 138	struct dma_chan			*chan_rx_saved;
 139	dma_cookie_t			cookie_tx;
 140	dma_cookie_t			cookie_rx[2];
 141	dma_cookie_t			active_rx;
 142	dma_addr_t			tx_dma_addr;
 143	unsigned int			tx_dma_len;
 144	struct scatterlist		sg_rx[2];
 145	void				*rx_buf[2];
 146	size_t				buf_len_rx;
 147	struct work_struct		work_tx;
 148	struct hrtimer			rx_timer;
 149	unsigned int			rx_timeout;	/* microseconds */
 150#endif
 151	unsigned int			rx_frame;
 152	int				rx_trigger;
 153	struct timer_list		rx_fifo_timer;
 154	int				rx_fifo_timeout;
 155	u16				hscif_tot;
 156
 157	bool has_rtscts;
 158	bool autorts;
 159};
 160
 161#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
 162
 163static struct sci_port sci_ports[SCI_NPORTS];
 164static unsigned long sci_ports_in_use;
 165static struct uart_driver sci_uart_driver;
 166
 167static inline struct sci_port *
 168to_sci_port(struct uart_port *uart)
 169{
 170	return container_of(uart, struct sci_port, port);
 171}
 172
 173static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
 174	/*
 175	 * Common SCI definitions, dependent on the port's regshift
 176	 * value.
 177	 */
 178	[SCIx_SCI_REGTYPE] = {
 179		.regs = {
 180			[SCSMR]		= { 0x00,  8 },
 181			[SCBRR]		= { 0x01,  8 },
 182			[SCSCR]		= { 0x02,  8 },
 183			[SCxTDR]	= { 0x03,  8 },
 184			[SCxSR]		= { 0x04,  8 },
 185			[SCxRDR]	= { 0x05,  8 },
 186		},
 187		.fifosize = 1,
 188		.overrun_reg = SCxSR,
 189		.overrun_mask = SCI_ORER,
 190		.sampling_rate_mask = SCI_SR(32),
 191		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 192		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 193	},
 194
 195	/*
 196	 * Common definitions for legacy IrDA ports.
 197	 */
 198	[SCIx_IRDA_REGTYPE] = {
 199		.regs = {
 200			[SCSMR]		= { 0x00,  8 },
 201			[SCBRR]		= { 0x02,  8 },
 202			[SCSCR]		= { 0x04,  8 },
 203			[SCxTDR]	= { 0x06,  8 },
 204			[SCxSR]		= { 0x08, 16 },
 205			[SCxRDR]	= { 0x0a,  8 },
 206			[SCFCR]		= { 0x0c,  8 },
 207			[SCFDR]		= { 0x0e, 16 },
 208		},
 209		.fifosize = 1,
 210		.overrun_reg = SCxSR,
 211		.overrun_mask = SCI_ORER,
 212		.sampling_rate_mask = SCI_SR(32),
 213		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 214		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 215	},
 216
 217	/*
 218	 * Common SCIFA definitions.
 219	 */
 220	[SCIx_SCIFA_REGTYPE] = {
 221		.regs = {
 222			[SCSMR]		= { 0x00, 16 },
 223			[SCBRR]		= { 0x04,  8 },
 224			[SCSCR]		= { 0x08, 16 },
 225			[SCxTDR]	= { 0x20,  8 },
 226			[SCxSR]		= { 0x14, 16 },
 227			[SCxRDR]	= { 0x24,  8 },
 228			[SCFCR]		= { 0x18, 16 },
 229			[SCFDR]		= { 0x1c, 16 },
 230			[SCPCR]		= { 0x30, 16 },
 231			[SCPDR]		= { 0x34, 16 },
 232		},
 233		.fifosize = 64,
 234		.overrun_reg = SCxSR,
 235		.overrun_mask = SCIFA_ORER,
 236		.sampling_rate_mask = SCI_SR_SCIFAB,
 237		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 238		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 239	},
 240
 241	/*
 242	 * Common SCIFB definitions.
 243	 */
 244	[SCIx_SCIFB_REGTYPE] = {
 245		.regs = {
 246			[SCSMR]		= { 0x00, 16 },
 247			[SCBRR]		= { 0x04,  8 },
 248			[SCSCR]		= { 0x08, 16 },
 249			[SCxTDR]	= { 0x40,  8 },
 250			[SCxSR]		= { 0x14, 16 },
 251			[SCxRDR]	= { 0x60,  8 },
 252			[SCFCR]		= { 0x18, 16 },
 253			[SCTFDR]	= { 0x38, 16 },
 254			[SCRFDR]	= { 0x3c, 16 },
 255			[SCPCR]		= { 0x30, 16 },
 256			[SCPDR]		= { 0x34, 16 },
 257		},
 258		.fifosize = 256,
 259		.overrun_reg = SCxSR,
 260		.overrun_mask = SCIFA_ORER,
 261		.sampling_rate_mask = SCI_SR_SCIFAB,
 262		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 263		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 264	},
 265
 266	/*
 267	 * Common SH-2(A) SCIF definitions for ports with FIFO data
 268	 * count registers.
 269	 */
 270	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
 271		.regs = {
 272			[SCSMR]		= { 0x00, 16 },
 273			[SCBRR]		= { 0x04,  8 },
 274			[SCSCR]		= { 0x08, 16 },
 275			[SCxTDR]	= { 0x0c,  8 },
 276			[SCxSR]		= { 0x10, 16 },
 277			[SCxRDR]	= { 0x14,  8 },
 278			[SCFCR]		= { 0x18, 16 },
 279			[SCFDR]		= { 0x1c, 16 },
 280			[SCSPTR]	= { 0x20, 16 },
 281			[SCLSR]		= { 0x24, 16 },
 282		},
 283		.fifosize = 16,
 284		.overrun_reg = SCLSR,
 285		.overrun_mask = SCLSR_ORER,
 286		.sampling_rate_mask = SCI_SR(32),
 287		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 288		.error_clear = SCIF_ERROR_CLEAR,
 289	},
 290
 291	/*
 292	 * The "SCIFA" that is in RZ/A2, RZ/G2L and RZ/T.
 293	 * It looks like a normal SCIF with FIFO data, but with a
 294	 * compressed address space. Also, the break out of interrupts
 295	 * are different: ERI/BRI, RXI, TXI, TEI, DRI.
 296	 */
 297	[SCIx_RZ_SCIFA_REGTYPE] = {
 298		.regs = {
 299			[SCSMR]		= { 0x00, 16 },
 300			[SCBRR]		= { 0x02,  8 },
 301			[SCSCR]		= { 0x04, 16 },
 302			[SCxTDR]	= { 0x06,  8 },
 303			[SCxSR]		= { 0x08, 16 },
 304			[SCxRDR]	= { 0x0A,  8 },
 305			[SCFCR]		= { 0x0C, 16 },
 306			[SCFDR]		= { 0x0E, 16 },
 307			[SCSPTR]	= { 0x10, 16 },
 308			[SCLSR]		= { 0x12, 16 },
 309			[SEMR]		= { 0x14, 8 },
 310		},
 311		.fifosize = 16,
 312		.overrun_reg = SCLSR,
 313		.overrun_mask = SCLSR_ORER,
 314		.sampling_rate_mask = SCI_SR(32),
 315		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 316		.error_clear = SCIF_ERROR_CLEAR,
 317	},
 318
 319	/*
 320	 * Common SH-3 SCIF definitions.
 321	 */
 322	[SCIx_SH3_SCIF_REGTYPE] = {
 323		.regs = {
 324			[SCSMR]		= { 0x00,  8 },
 325			[SCBRR]		= { 0x02,  8 },
 326			[SCSCR]		= { 0x04,  8 },
 327			[SCxTDR]	= { 0x06,  8 },
 328			[SCxSR]		= { 0x08, 16 },
 329			[SCxRDR]	= { 0x0a,  8 },
 330			[SCFCR]		= { 0x0c,  8 },
 331			[SCFDR]		= { 0x0e, 16 },
 332		},
 333		.fifosize = 16,
 334		.overrun_reg = SCLSR,
 335		.overrun_mask = SCLSR_ORER,
 336		.sampling_rate_mask = SCI_SR(32),
 337		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 338		.error_clear = SCIF_ERROR_CLEAR,
 339	},
 340
 341	/*
 342	 * Common SH-4(A) SCIF(B) definitions.
 343	 */
 344	[SCIx_SH4_SCIF_REGTYPE] = {
 345		.regs = {
 346			[SCSMR]		= { 0x00, 16 },
 347			[SCBRR]		= { 0x04,  8 },
 348			[SCSCR]		= { 0x08, 16 },
 349			[SCxTDR]	= { 0x0c,  8 },
 350			[SCxSR]		= { 0x10, 16 },
 351			[SCxRDR]	= { 0x14,  8 },
 352			[SCFCR]		= { 0x18, 16 },
 353			[SCFDR]		= { 0x1c, 16 },
 354			[SCSPTR]	= { 0x20, 16 },
 355			[SCLSR]		= { 0x24, 16 },
 356		},
 357		.fifosize = 16,
 358		.overrun_reg = SCLSR,
 359		.overrun_mask = SCLSR_ORER,
 360		.sampling_rate_mask = SCI_SR(32),
 361		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 362		.error_clear = SCIF_ERROR_CLEAR,
 363	},
 364
 365	/*
 366	 * Common SCIF definitions for ports with a Baud Rate Generator for
 367	 * External Clock (BRG).
 368	 */
 369	[SCIx_SH4_SCIF_BRG_REGTYPE] = {
 370		.regs = {
 371			[SCSMR]		= { 0x00, 16 },
 372			[SCBRR]		= { 0x04,  8 },
 373			[SCSCR]		= { 0x08, 16 },
 374			[SCxTDR]	= { 0x0c,  8 },
 375			[SCxSR]		= { 0x10, 16 },
 376			[SCxRDR]	= { 0x14,  8 },
 377			[SCFCR]		= { 0x18, 16 },
 378			[SCFDR]		= { 0x1c, 16 },
 379			[SCSPTR]	= { 0x20, 16 },
 380			[SCLSR]		= { 0x24, 16 },
 381			[SCDL]		= { 0x30, 16 },
 382			[SCCKS]		= { 0x34, 16 },
 383		},
 384		.fifosize = 16,
 385		.overrun_reg = SCLSR,
 386		.overrun_mask = SCLSR_ORER,
 387		.sampling_rate_mask = SCI_SR(32),
 388		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 389		.error_clear = SCIF_ERROR_CLEAR,
 390	},
 391
 392	/*
 393	 * Common HSCIF definitions.
 394	 */
 395	[SCIx_HSCIF_REGTYPE] = {
 396		.regs = {
 397			[SCSMR]		= { 0x00, 16 },
 398			[SCBRR]		= { 0x04,  8 },
 399			[SCSCR]		= { 0x08, 16 },
 400			[SCxTDR]	= { 0x0c,  8 },
 401			[SCxSR]		= { 0x10, 16 },
 402			[SCxRDR]	= { 0x14,  8 },
 403			[SCFCR]		= { 0x18, 16 },
 404			[SCFDR]		= { 0x1c, 16 },
 405			[SCSPTR]	= { 0x20, 16 },
 406			[SCLSR]		= { 0x24, 16 },
 407			[HSSRR]		= { 0x40, 16 },
 408			[SCDL]		= { 0x30, 16 },
 409			[SCCKS]		= { 0x34, 16 },
 410			[HSRTRGR]	= { 0x54, 16 },
 411			[HSTTRGR]	= { 0x58, 16 },
 412		},
 413		.fifosize = 128,
 414		.overrun_reg = SCLSR,
 415		.overrun_mask = SCLSR_ORER,
 416		.sampling_rate_mask = SCI_SR_RANGE(8, 32),
 417		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 418		.error_clear = SCIF_ERROR_CLEAR,
 419	},
 420
 421	/*
 422	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
 423	 * register.
 424	 */
 425	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
 426		.regs = {
 427			[SCSMR]		= { 0x00, 16 },
 428			[SCBRR]		= { 0x04,  8 },
 429			[SCSCR]		= { 0x08, 16 },
 430			[SCxTDR]	= { 0x0c,  8 },
 431			[SCxSR]		= { 0x10, 16 },
 432			[SCxRDR]	= { 0x14,  8 },
 433			[SCFCR]		= { 0x18, 16 },
 434			[SCFDR]		= { 0x1c, 16 },
 435			[SCLSR]		= { 0x24, 16 },
 436		},
 437		.fifosize = 16,
 438		.overrun_reg = SCLSR,
 439		.overrun_mask = SCLSR_ORER,
 440		.sampling_rate_mask = SCI_SR(32),
 441		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 442		.error_clear = SCIF_ERROR_CLEAR,
 443	},
 444
 445	/*
 446	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
 447	 * count registers.
 448	 */
 449	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
 450		.regs = {
 451			[SCSMR]		= { 0x00, 16 },
 452			[SCBRR]		= { 0x04,  8 },
 453			[SCSCR]		= { 0x08, 16 },
 454			[SCxTDR]	= { 0x0c,  8 },
 455			[SCxSR]		= { 0x10, 16 },
 456			[SCxRDR]	= { 0x14,  8 },
 457			[SCFCR]		= { 0x18, 16 },
 458			[SCFDR]		= { 0x1c, 16 },
 459			[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
 460			[SCRFDR]	= { 0x20, 16 },
 461			[SCSPTR]	= { 0x24, 16 },
 462			[SCLSR]		= { 0x28, 16 },
 463		},
 464		.fifosize = 16,
 465		.overrun_reg = SCLSR,
 466		.overrun_mask = SCLSR_ORER,
 467		.sampling_rate_mask = SCI_SR(32),
 468		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 469		.error_clear = SCIF_ERROR_CLEAR,
 470	},
 471
 472	/*
 473	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
 474	 * registers.
 475	 */
 476	[SCIx_SH7705_SCIF_REGTYPE] = {
 477		.regs = {
 478			[SCSMR]		= { 0x00, 16 },
 479			[SCBRR]		= { 0x04,  8 },
 480			[SCSCR]		= { 0x08, 16 },
 481			[SCxTDR]	= { 0x20,  8 },
 482			[SCxSR]		= { 0x14, 16 },
 483			[SCxRDR]	= { 0x24,  8 },
 484			[SCFCR]		= { 0x18, 16 },
 485			[SCFDR]		= { 0x1c, 16 },
 486		},
 487		.fifosize = 64,
 488		.overrun_reg = SCxSR,
 489		.overrun_mask = SCIFA_ORER,
 490		.sampling_rate_mask = SCI_SR(16),
 491		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 492		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 493	},
 494};
 495
 496#define sci_getreg(up, offset)		(&to_sci_port(up)->params->regs[offset])
 497
 498/*
 499 * The "offset" here is rather misleading, in that it refers to an enum
 500 * value relative to the port mapping rather than the fixed offset
 501 * itself, which needs to be manually retrieved from the platform's
 502 * register map for the given port.
 503 */
 504static unsigned int sci_serial_in(struct uart_port *p, int offset)
 505{
 506	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 507
 508	if (reg->size == 8)
 509		return ioread8(p->membase + (reg->offset << p->regshift));
 510	else if (reg->size == 16)
 511		return ioread16(p->membase + (reg->offset << p->regshift));
 512	else
 513		WARN(1, "Invalid register access\n");
 514
 515	return 0;
 516}
 517
 518static void sci_serial_out(struct uart_port *p, int offset, int value)
 519{
 520	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 521
 522	if (reg->size == 8)
 523		iowrite8(value, p->membase + (reg->offset << p->regshift));
 524	else if (reg->size == 16)
 525		iowrite16(value, p->membase + (reg->offset << p->regshift));
 526	else
 527		WARN(1, "Invalid register access\n");
 528}
 529
 530static void sci_port_enable(struct sci_port *sci_port)
 531{
 532	unsigned int i;
 533
 534	if (!sci_port->port.dev)
 535		return;
 536
 537	pm_runtime_get_sync(sci_port->port.dev);
 538
 539	for (i = 0; i < SCI_NUM_CLKS; i++) {
 540		clk_prepare_enable(sci_port->clks[i]);
 541		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
 542	}
 543	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
 544}
 545
 546static void sci_port_disable(struct sci_port *sci_port)
 547{
 548	unsigned int i;
 549
 550	if (!sci_port->port.dev)
 551		return;
 552
 553	for (i = SCI_NUM_CLKS; i-- > 0; )
 554		clk_disable_unprepare(sci_port->clks[i]);
 555
 556	pm_runtime_put_sync(sci_port->port.dev);
 557}
 558
 559static inline unsigned long port_rx_irq_mask(struct uart_port *port)
 560{
 561	/*
 562	 * Not all ports (such as SCIFA) will support REIE. Rather than
 563	 * special-casing the port type, we check the port initialization
 564	 * IRQ enable mask to see whether the IRQ is desired at all. If
 565	 * it's unset, it's logically inferred that there's no point in
 566	 * testing for it.
 567	 */
 568	return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
 569}
 570
 571static void sci_start_tx(struct uart_port *port)
 572{
 573	struct sci_port *s = to_sci_port(port);
 574	unsigned short ctrl;
 575
 576#ifdef CONFIG_SERIAL_SH_SCI_DMA
 577	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 578		u16 new, scr = serial_port_in(port, SCSCR);
 579		if (s->chan_tx)
 580			new = scr | SCSCR_TDRQE;
 581		else
 582			new = scr & ~SCSCR_TDRQE;
 583		if (new != scr)
 584			serial_port_out(port, SCSCR, new);
 585	}
 586
 587	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
 588	    dma_submit_error(s->cookie_tx)) {
 
 
 
 
 589		s->cookie_tx = 0;
 590		schedule_work(&s->work_tx);
 591	}
 592#endif
 593
 594	if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 
 595		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
 596		ctrl = serial_port_in(port, SCSCR);
 
 
 
 
 
 
 
 
 
 597		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
 598	}
 599}
 600
 601static void sci_stop_tx(struct uart_port *port)
 602{
 603	unsigned short ctrl;
 604
 605	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
 606	ctrl = serial_port_in(port, SCSCR);
 607
 608	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 609		ctrl &= ~SCSCR_TDRQE;
 610
 611	ctrl &= ~SCSCR_TIE;
 612
 613	serial_port_out(port, SCSCR, ctrl);
 614
 615#ifdef CONFIG_SERIAL_SH_SCI_DMA
 616	if (to_sci_port(port)->chan_tx &&
 617	    !dma_submit_error(to_sci_port(port)->cookie_tx)) {
 618		dmaengine_terminate_async(to_sci_port(port)->chan_tx);
 619		to_sci_port(port)->cookie_tx = -EINVAL;
 620	}
 621#endif
 622}
 623
 624static void sci_start_rx(struct uart_port *port)
 625{
 626	unsigned short ctrl;
 627
 628	ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
 629
 630	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 631		ctrl &= ~SCSCR_RDRQE;
 632
 633	serial_port_out(port, SCSCR, ctrl);
 634}
 635
 636static void sci_stop_rx(struct uart_port *port)
 637{
 638	unsigned short ctrl;
 639
 640	ctrl = serial_port_in(port, SCSCR);
 641
 642	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 643		ctrl &= ~SCSCR_RDRQE;
 644
 645	ctrl &= ~port_rx_irq_mask(port);
 646
 647	serial_port_out(port, SCSCR, ctrl);
 648}
 649
 650static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
 651{
 652	if (port->type == PORT_SCI) {
 653		/* Just store the mask */
 654		serial_port_out(port, SCxSR, mask);
 655	} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
 656		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
 657		/* Only clear the status bits we want to clear */
 658		serial_port_out(port, SCxSR,
 659				serial_port_in(port, SCxSR) & mask);
 660	} else {
 661		/* Store the mask, clear parity/framing errors */
 662		serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
 663	}
 664}
 665
 666#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
 667    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
 668
 669#ifdef CONFIG_CONSOLE_POLL
 670static int sci_poll_get_char(struct uart_port *port)
 671{
 672	unsigned short status;
 673	int c;
 674
 675	do {
 676		status = serial_port_in(port, SCxSR);
 677		if (status & SCxSR_ERRORS(port)) {
 678			sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
 679			continue;
 680		}
 681		break;
 682	} while (1);
 683
 684	if (!(status & SCxSR_RDxF(port)))
 685		return NO_POLL_CHAR;
 686
 687	c = serial_port_in(port, SCxRDR);
 688
 689	/* Dummy read */
 690	serial_port_in(port, SCxSR);
 691	sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 692
 693	return c;
 694}
 695#endif
 696
 697static void sci_poll_put_char(struct uart_port *port, unsigned char c)
 698{
 699	unsigned short status;
 700
 701	do {
 702		status = serial_port_in(port, SCxSR);
 703	} while (!(status & SCxSR_TDxE(port)));
 704
 705	serial_port_out(port, SCxTDR, c);
 706	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
 707}
 708#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
 709	  CONFIG_SERIAL_SH_SCI_EARLYCON */
 710
 711static void sci_init_pins(struct uart_port *port, unsigned int cflag)
 712{
 713	struct sci_port *s = to_sci_port(port);
 714
 715	/*
 716	 * Use port-specific handler if provided.
 717	 */
 718	if (s->cfg->ops && s->cfg->ops->init_pins) {
 719		s->cfg->ops->init_pins(port, cflag);
 720		return;
 721	}
 722
 723	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 724		u16 data = serial_port_in(port, SCPDR);
 725		u16 ctrl = serial_port_in(port, SCPCR);
 726
 727		/* Enable RXD and TXD pin functions */
 728		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
 729		if (to_sci_port(port)->has_rtscts) {
 730			/* RTS# is output, active low, unless autorts */
 731			if (!(port->mctrl & TIOCM_RTS)) {
 732				ctrl |= SCPCR_RTSC;
 733				data |= SCPDR_RTSD;
 734			} else if (!s->autorts) {
 735				ctrl |= SCPCR_RTSC;
 736				data &= ~SCPDR_RTSD;
 737			} else {
 738				/* Enable RTS# pin function */
 739				ctrl &= ~SCPCR_RTSC;
 740			}
 741			/* Enable CTS# pin function */
 742			ctrl &= ~SCPCR_CTSC;
 743		}
 744		serial_port_out(port, SCPDR, data);
 745		serial_port_out(port, SCPCR, ctrl);
 746	} else if (sci_getreg(port, SCSPTR)->size) {
 747		u16 status = serial_port_in(port, SCSPTR);
 748
 749		/* RTS# is always output; and active low, unless autorts */
 750		status |= SCSPTR_RTSIO;
 751		if (!(port->mctrl & TIOCM_RTS))
 752			status |= SCSPTR_RTSDT;
 753		else if (!s->autorts)
 754			status &= ~SCSPTR_RTSDT;
 755		/* CTS# and SCK are inputs */
 756		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
 757		serial_port_out(port, SCSPTR, status);
 758	}
 759}
 760
 761static int sci_txfill(struct uart_port *port)
 762{
 763	struct sci_port *s = to_sci_port(port);
 764	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 765	const struct plat_sci_reg *reg;
 766
 767	reg = sci_getreg(port, SCTFDR);
 768	if (reg->size)
 769		return serial_port_in(port, SCTFDR) & fifo_mask;
 770
 771	reg = sci_getreg(port, SCFDR);
 772	if (reg->size)
 773		return serial_port_in(port, SCFDR) >> 8;
 774
 775	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
 776}
 777
 778static int sci_txroom(struct uart_port *port)
 779{
 780	return port->fifosize - sci_txfill(port);
 781}
 782
 783static int sci_rxfill(struct uart_port *port)
 784{
 785	struct sci_port *s = to_sci_port(port);
 786	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 787	const struct plat_sci_reg *reg;
 788
 789	reg = sci_getreg(port, SCRFDR);
 790	if (reg->size)
 791		return serial_port_in(port, SCRFDR) & fifo_mask;
 792
 793	reg = sci_getreg(port, SCFDR);
 794	if (reg->size)
 795		return serial_port_in(port, SCFDR) & fifo_mask;
 796
 797	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
 798}
 799
 800/* ********************************************************************** *
 801 *                   the interrupt related routines                       *
 802 * ********************************************************************** */
 803
 804static void sci_transmit_chars(struct uart_port *port)
 805{
 806	struct circ_buf *xmit = &port->state->xmit;
 807	unsigned int stopped = uart_tx_stopped(port);
 808	unsigned short status;
 809	unsigned short ctrl;
 810	int count;
 811
 812	status = serial_port_in(port, SCxSR);
 813	if (!(status & SCxSR_TDxE(port))) {
 814		ctrl = serial_port_in(port, SCSCR);
 815		if (uart_circ_empty(xmit))
 816			ctrl &= ~SCSCR_TIE;
 817		else
 818			ctrl |= SCSCR_TIE;
 819		serial_port_out(port, SCSCR, ctrl);
 820		return;
 821	}
 822
 823	count = sci_txroom(port);
 824
 825	do {
 826		unsigned char c;
 827
 828		if (port->x_char) {
 829			c = port->x_char;
 830			port->x_char = 0;
 831		} else if (!uart_circ_empty(xmit) && !stopped) {
 832			c = xmit->buf[xmit->tail];
 833			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 
 
 
 
 
 834		} else {
 835			break;
 836		}
 837
 838		serial_port_out(port, SCxTDR, c);
 839
 840		port->icount.tx++;
 841	} while (--count > 0);
 842
 843	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
 844
 845	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 846		uart_write_wakeup(port);
 847	if (uart_circ_empty(xmit))
 
 
 
 
 
 
 
 848		sci_stop_tx(port);
 849
 850}
 851
 852static void sci_receive_chars(struct uart_port *port)
 853{
 854	struct tty_port *tport = &port->state->port;
 855	int i, count, copied = 0;
 856	unsigned short status;
 857	unsigned char flag;
 858
 859	status = serial_port_in(port, SCxSR);
 860	if (!(status & SCxSR_RDxF(port)))
 861		return;
 862
 863	while (1) {
 864		/* Don't copy more bytes than there is room for in the buffer */
 865		count = tty_buffer_request_room(tport, sci_rxfill(port));
 866
 867		/* If for any reason we can't copy more data, we're done! */
 868		if (count == 0)
 869			break;
 870
 871		if (port->type == PORT_SCI) {
 872			char c = serial_port_in(port, SCxRDR);
 873			if (uart_handle_sysrq_char(port, c))
 874				count = 0;
 875			else
 876				tty_insert_flip_char(tport, c, TTY_NORMAL);
 877		} else {
 878			for (i = 0; i < count; i++) {
 879				char c;
 880
 881				if (port->type == PORT_SCIF ||
 882				    port->type == PORT_HSCIF) {
 883					status = serial_port_in(port, SCxSR);
 884					c = serial_port_in(port, SCxRDR);
 885				} else {
 886					c = serial_port_in(port, SCxRDR);
 887					status = serial_port_in(port, SCxSR);
 888				}
 889				if (uart_handle_sysrq_char(port, c)) {
 890					count--; i--;
 891					continue;
 892				}
 893
 894				/* Store data and status */
 895				if (status & SCxSR_FER(port)) {
 896					flag = TTY_FRAME;
 897					port->icount.frame++;
 898					dev_notice(port->dev, "frame error\n");
 899				} else if (status & SCxSR_PER(port)) {
 900					flag = TTY_PARITY;
 901					port->icount.parity++;
 902					dev_notice(port->dev, "parity error\n");
 903				} else
 904					flag = TTY_NORMAL;
 905
 906				tty_insert_flip_char(tport, c, flag);
 907			}
 908		}
 909
 910		serial_port_in(port, SCxSR); /* dummy read */
 911		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 912
 913		copied += count;
 914		port->icount.rx += count;
 915	}
 916
 917	if (copied) {
 918		/* Tell the rest of the system the news. New characters! */
 919		tty_flip_buffer_push(tport);
 920	} else {
 921		/* TTY buffers full; read from RX reg to prevent lockup */
 922		serial_port_in(port, SCxRDR);
 923		serial_port_in(port, SCxSR); /* dummy read */
 924		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 925	}
 926}
 927
 928static int sci_handle_errors(struct uart_port *port)
 929{
 930	int copied = 0;
 931	unsigned short status = serial_port_in(port, SCxSR);
 932	struct tty_port *tport = &port->state->port;
 933	struct sci_port *s = to_sci_port(port);
 934
 935	/* Handle overruns */
 936	if (status & s->params->overrun_mask) {
 937		port->icount.overrun++;
 938
 939		/* overrun error */
 940		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
 941			copied++;
 942
 943		dev_notice(port->dev, "overrun error\n");
 944	}
 945
 946	if (status & SCxSR_FER(port)) {
 947		/* frame error */
 948		port->icount.frame++;
 949
 950		if (tty_insert_flip_char(tport, 0, TTY_FRAME))
 951			copied++;
 952
 953		dev_notice(port->dev, "frame error\n");
 954	}
 955
 956	if (status & SCxSR_PER(port)) {
 957		/* parity error */
 958		port->icount.parity++;
 959
 960		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
 961			copied++;
 962
 963		dev_notice(port->dev, "parity error\n");
 964	}
 965
 966	if (copied)
 967		tty_flip_buffer_push(tport);
 968
 969	return copied;
 970}
 971
 972static int sci_handle_fifo_overrun(struct uart_port *port)
 973{
 974	struct tty_port *tport = &port->state->port;
 975	struct sci_port *s = to_sci_port(port);
 976	const struct plat_sci_reg *reg;
 977	int copied = 0;
 978	u16 status;
 979
 980	reg = sci_getreg(port, s->params->overrun_reg);
 981	if (!reg->size)
 982		return 0;
 983
 984	status = serial_port_in(port, s->params->overrun_reg);
 985	if (status & s->params->overrun_mask) {
 986		status &= ~s->params->overrun_mask;
 987		serial_port_out(port, s->params->overrun_reg, status);
 988
 989		port->icount.overrun++;
 990
 991		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 992		tty_flip_buffer_push(tport);
 993
 994		dev_dbg(port->dev, "overrun error\n");
 995		copied++;
 996	}
 997
 998	return copied;
 999}
1000
1001static int sci_handle_breaks(struct uart_port *port)
1002{
1003	int copied = 0;
1004	unsigned short status = serial_port_in(port, SCxSR);
1005	struct tty_port *tport = &port->state->port;
1006
1007	if (uart_handle_break(port))
1008		return 0;
1009
1010	if (status & SCxSR_BRK(port)) {
1011		port->icount.brk++;
1012
1013		/* Notify of BREAK */
1014		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1015			copied++;
1016
1017		dev_dbg(port->dev, "BREAK detected\n");
1018	}
1019
1020	if (copied)
1021		tty_flip_buffer_push(tport);
1022
1023	copied += sci_handle_fifo_overrun(port);
1024
1025	return copied;
1026}
1027
1028static int scif_set_rtrg(struct uart_port *port, int rx_trig)
1029{
1030	unsigned int bits;
1031
1032	if (rx_trig >= port->fifosize)
1033		rx_trig = port->fifosize - 1;
1034	if (rx_trig < 1)
1035		rx_trig = 1;
1036
1037	/* HSCIF can be set to an arbitrary level. */
1038	if (sci_getreg(port, HSRTRGR)->size) {
1039		serial_port_out(port, HSRTRGR, rx_trig);
1040		return rx_trig;
1041	}
1042
1043	switch (port->type) {
1044	case PORT_SCIF:
1045		if (rx_trig < 4) {
1046			bits = 0;
1047			rx_trig = 1;
1048		} else if (rx_trig < 8) {
1049			bits = SCFCR_RTRG0;
1050			rx_trig = 4;
1051		} else if (rx_trig < 14) {
1052			bits = SCFCR_RTRG1;
1053			rx_trig = 8;
1054		} else {
1055			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1056			rx_trig = 14;
1057		}
1058		break;
1059	case PORT_SCIFA:
1060	case PORT_SCIFB:
1061		if (rx_trig < 16) {
1062			bits = 0;
1063			rx_trig = 1;
1064		} else if (rx_trig < 32) {
1065			bits = SCFCR_RTRG0;
1066			rx_trig = 16;
1067		} else if (rx_trig < 48) {
1068			bits = SCFCR_RTRG1;
1069			rx_trig = 32;
1070		} else {
1071			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1072			rx_trig = 48;
1073		}
1074		break;
1075	default:
1076		WARN(1, "unknown FIFO configuration");
1077		return 1;
1078	}
1079
1080	serial_port_out(port, SCFCR,
1081		(serial_port_in(port, SCFCR) &
1082		~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1083
1084	return rx_trig;
1085}
1086
1087static int scif_rtrg_enabled(struct uart_port *port)
1088{
1089	if (sci_getreg(port, HSRTRGR)->size)
1090		return serial_port_in(port, HSRTRGR) != 0;
1091	else
1092		return (serial_port_in(port, SCFCR) &
1093			(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1094}
1095
1096static void rx_fifo_timer_fn(struct timer_list *t)
1097{
1098	struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1099	struct uart_port *port = &s->port;
1100
1101	dev_dbg(port->dev, "Rx timed out\n");
1102	scif_set_rtrg(port, 1);
1103}
1104
1105static ssize_t rx_fifo_trigger_show(struct device *dev,
1106				    struct device_attribute *attr, char *buf)
1107{
1108	struct uart_port *port = dev_get_drvdata(dev);
1109	struct sci_port *sci = to_sci_port(port);
1110
1111	return sprintf(buf, "%d\n", sci->rx_trigger);
1112}
1113
1114static ssize_t rx_fifo_trigger_store(struct device *dev,
1115				     struct device_attribute *attr,
1116				     const char *buf, size_t count)
1117{
1118	struct uart_port *port = dev_get_drvdata(dev);
1119	struct sci_port *sci = to_sci_port(port);
1120	int ret;
1121	long r;
1122
1123	ret = kstrtol(buf, 0, &r);
1124	if (ret)
1125		return ret;
1126
1127	sci->rx_trigger = scif_set_rtrg(port, r);
1128	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1129		scif_set_rtrg(port, 1);
1130
1131	return count;
1132}
1133
1134static DEVICE_ATTR_RW(rx_fifo_trigger);
1135
1136static ssize_t rx_fifo_timeout_show(struct device *dev,
1137			       struct device_attribute *attr,
1138			       char *buf)
1139{
1140	struct uart_port *port = dev_get_drvdata(dev);
1141	struct sci_port *sci = to_sci_port(port);
1142	int v;
1143
1144	if (port->type == PORT_HSCIF)
1145		v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1146	else
1147		v = sci->rx_fifo_timeout;
1148
1149	return sprintf(buf, "%d\n", v);
1150}
1151
1152static ssize_t rx_fifo_timeout_store(struct device *dev,
1153				struct device_attribute *attr,
1154				const char *buf,
1155				size_t count)
1156{
1157	struct uart_port *port = dev_get_drvdata(dev);
1158	struct sci_port *sci = to_sci_port(port);
1159	int ret;
1160	long r;
1161
1162	ret = kstrtol(buf, 0, &r);
1163	if (ret)
1164		return ret;
1165
1166	if (port->type == PORT_HSCIF) {
1167		if (r < 0 || r > 3)
1168			return -EINVAL;
1169		sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1170	} else {
1171		sci->rx_fifo_timeout = r;
1172		scif_set_rtrg(port, 1);
1173		if (r > 0)
1174			timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1175	}
1176
1177	return count;
1178}
1179
1180static DEVICE_ATTR_RW(rx_fifo_timeout);
1181
1182
1183#ifdef CONFIG_SERIAL_SH_SCI_DMA
1184static void sci_dma_tx_complete(void *arg)
1185{
1186	struct sci_port *s = arg;
1187	struct uart_port *port = &s->port;
1188	struct circ_buf *xmit = &port->state->xmit;
1189	unsigned long flags;
1190
1191	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1192
1193	spin_lock_irqsave(&port->lock, flags);
1194
1195	xmit->tail += s->tx_dma_len;
1196	xmit->tail &= UART_XMIT_SIZE - 1;
1197
1198	port->icount.tx += s->tx_dma_len;
1199
1200	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1201		uart_write_wakeup(port);
1202
1203	if (!uart_circ_empty(xmit)) {
1204		s->cookie_tx = 0;
1205		schedule_work(&s->work_tx);
1206	} else {
1207		s->cookie_tx = -EINVAL;
1208		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 
1209			u16 ctrl = serial_port_in(port, SCSCR);
1210			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
 
 
 
 
 
1211		}
1212	}
1213
1214	spin_unlock_irqrestore(&port->lock, flags);
1215}
1216
1217/* Locking: called with port lock held */
1218static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1219{
1220	struct uart_port *port = &s->port;
1221	struct tty_port *tport = &port->state->port;
1222	int copied;
1223
1224	copied = tty_insert_flip_string(tport, buf, count);
1225	if (copied < count)
1226		port->icount.buf_overrun++;
1227
1228	port->icount.rx += copied;
1229
1230	return copied;
1231}
1232
1233static int sci_dma_rx_find_active(struct sci_port *s)
1234{
1235	unsigned int i;
1236
1237	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1238		if (s->active_rx == s->cookie_rx[i])
1239			return i;
1240
1241	return -1;
1242}
1243
1244static void sci_dma_rx_chan_invalidate(struct sci_port *s)
1245{
1246	unsigned int i;
1247
1248	s->chan_rx = NULL;
1249	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1250		s->cookie_rx[i] = -EINVAL;
1251	s->active_rx = 0;
1252}
1253
1254static void sci_dma_rx_release(struct sci_port *s)
1255{
1256	struct dma_chan *chan = s->chan_rx_saved;
1257
1258	s->chan_rx_saved = NULL;
1259	sci_dma_rx_chan_invalidate(s);
1260	dmaengine_terminate_sync(chan);
1261	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1262			  sg_dma_address(&s->sg_rx[0]));
1263	dma_release_channel(chan);
1264}
1265
1266static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1267{
1268	long sec = usec / 1000000;
1269	long nsec = (usec % 1000000) * 1000;
1270	ktime_t t = ktime_set(sec, nsec);
1271
1272	hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1273}
1274
1275static void sci_dma_rx_reenable_irq(struct sci_port *s)
1276{
1277	struct uart_port *port = &s->port;
1278	u16 scr;
1279
1280	/* Direct new serial port interrupts back to CPU */
1281	scr = serial_port_in(port, SCSCR);
1282	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1283		scr &= ~SCSCR_RDRQE;
1284		enable_irq(s->irqs[SCIx_RXI_IRQ]);
 
 
 
 
1285	}
1286	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1287}
1288
1289static void sci_dma_rx_complete(void *arg)
1290{
1291	struct sci_port *s = arg;
1292	struct dma_chan *chan = s->chan_rx;
1293	struct uart_port *port = &s->port;
1294	struct dma_async_tx_descriptor *desc;
1295	unsigned long flags;
1296	int active, count = 0;
1297
1298	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1299		s->active_rx);
1300
1301	spin_lock_irqsave(&port->lock, flags);
1302
1303	active = sci_dma_rx_find_active(s);
1304	if (active >= 0)
1305		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1306
1307	start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1308
1309	if (count)
1310		tty_flip_buffer_push(&port->state->port);
1311
1312	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1313				       DMA_DEV_TO_MEM,
1314				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1315	if (!desc)
1316		goto fail;
1317
1318	desc->callback = sci_dma_rx_complete;
1319	desc->callback_param = s;
1320	s->cookie_rx[active] = dmaengine_submit(desc);
1321	if (dma_submit_error(s->cookie_rx[active]))
1322		goto fail;
1323
1324	s->active_rx = s->cookie_rx[!active];
1325
1326	dma_async_issue_pending(chan);
1327
1328	spin_unlock_irqrestore(&port->lock, flags);
1329	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1330		__func__, s->cookie_rx[active], active, s->active_rx);
1331	return;
1332
1333fail:
1334	spin_unlock_irqrestore(&port->lock, flags);
1335	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1336	/* Switch to PIO */
1337	spin_lock_irqsave(&port->lock, flags);
1338	dmaengine_terminate_async(chan);
1339	sci_dma_rx_chan_invalidate(s);
1340	sci_dma_rx_reenable_irq(s);
1341	spin_unlock_irqrestore(&port->lock, flags);
1342}
1343
1344static void sci_dma_tx_release(struct sci_port *s)
1345{
1346	struct dma_chan *chan = s->chan_tx_saved;
1347
1348	cancel_work_sync(&s->work_tx);
1349	s->chan_tx_saved = s->chan_tx = NULL;
1350	s->cookie_tx = -EINVAL;
1351	dmaengine_terminate_sync(chan);
1352	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1353			 DMA_TO_DEVICE);
1354	dma_release_channel(chan);
1355}
1356
1357static int sci_dma_rx_submit(struct sci_port *s, bool port_lock_held)
1358{
1359	struct dma_chan *chan = s->chan_rx;
1360	struct uart_port *port = &s->port;
1361	unsigned long flags;
1362	int i;
1363
1364	for (i = 0; i < 2; i++) {
1365		struct scatterlist *sg = &s->sg_rx[i];
1366		struct dma_async_tx_descriptor *desc;
1367
1368		desc = dmaengine_prep_slave_sg(chan,
1369			sg, 1, DMA_DEV_TO_MEM,
1370			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1371		if (!desc)
1372			goto fail;
1373
1374		desc->callback = sci_dma_rx_complete;
1375		desc->callback_param = s;
1376		s->cookie_rx[i] = dmaengine_submit(desc);
1377		if (dma_submit_error(s->cookie_rx[i]))
1378			goto fail;
1379
1380	}
1381
1382	s->active_rx = s->cookie_rx[0];
1383
1384	dma_async_issue_pending(chan);
1385	return 0;
1386
1387fail:
1388	/* Switch to PIO */
1389	if (!port_lock_held)
1390		spin_lock_irqsave(&port->lock, flags);
1391	if (i)
1392		dmaengine_terminate_async(chan);
1393	sci_dma_rx_chan_invalidate(s);
1394	sci_start_rx(port);
1395	if (!port_lock_held)
1396		spin_unlock_irqrestore(&port->lock, flags);
1397	return -EAGAIN;
1398}
1399
1400static void sci_dma_tx_work_fn(struct work_struct *work)
1401{
1402	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1403	struct dma_async_tx_descriptor *desc;
1404	struct dma_chan *chan = s->chan_tx;
1405	struct uart_port *port = &s->port;
1406	struct circ_buf *xmit = &port->state->xmit;
1407	unsigned long flags;
1408	dma_addr_t buf;
1409	int head, tail;
1410
1411	/*
1412	 * DMA is idle now.
1413	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1414	 * offsets and lengths. Since it is a circular buffer, we have to
1415	 * transmit till the end, and then the rest. Take the port lock to get a
1416	 * consistent xmit buffer state.
1417	 */
1418	spin_lock_irq(&port->lock);
1419	head = xmit->head;
1420	tail = xmit->tail;
1421	buf = s->tx_dma_addr + (tail & (UART_XMIT_SIZE - 1));
1422	s->tx_dma_len = min_t(unsigned int,
1423		CIRC_CNT(head, tail, UART_XMIT_SIZE),
1424		CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE));
1425	if (!s->tx_dma_len) {
1426		/* Transmit buffer has been flushed */
1427		spin_unlock_irq(&port->lock);
1428		return;
1429	}
1430
1431	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1432					   DMA_MEM_TO_DEV,
1433					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1434	if (!desc) {
1435		spin_unlock_irq(&port->lock);
1436		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1437		goto switch_to_pio;
1438	}
1439
1440	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1441				   DMA_TO_DEVICE);
1442
1443	desc->callback = sci_dma_tx_complete;
1444	desc->callback_param = s;
1445	s->cookie_tx = dmaengine_submit(desc);
1446	if (dma_submit_error(s->cookie_tx)) {
1447		spin_unlock_irq(&port->lock);
1448		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1449		goto switch_to_pio;
1450	}
1451
1452	spin_unlock_irq(&port->lock);
1453	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1454		__func__, xmit->buf, tail, head, s->cookie_tx);
1455
1456	dma_async_issue_pending(chan);
1457	return;
1458
1459switch_to_pio:
1460	spin_lock_irqsave(&port->lock, flags);
1461	s->chan_tx = NULL;
1462	sci_start_tx(port);
1463	spin_unlock_irqrestore(&port->lock, flags);
1464	return;
1465}
1466
1467static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
1468{
1469	struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1470	struct dma_chan *chan = s->chan_rx;
1471	struct uart_port *port = &s->port;
1472	struct dma_tx_state state;
1473	enum dma_status status;
1474	unsigned long flags;
1475	unsigned int read;
1476	int active, count;
1477
1478	dev_dbg(port->dev, "DMA Rx timed out\n");
1479
1480	spin_lock_irqsave(&port->lock, flags);
1481
1482	active = sci_dma_rx_find_active(s);
1483	if (active < 0) {
1484		spin_unlock_irqrestore(&port->lock, flags);
1485		return HRTIMER_NORESTART;
1486	}
1487
1488	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1489	if (status == DMA_COMPLETE) {
1490		spin_unlock_irqrestore(&port->lock, flags);
1491		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1492			s->active_rx, active);
1493
1494		/* Let packet complete handler take care of the packet */
1495		return HRTIMER_NORESTART;
1496	}
1497
1498	dmaengine_pause(chan);
1499
1500	/*
1501	 * sometimes DMA transfer doesn't stop even if it is stopped and
1502	 * data keeps on coming until transaction is complete so check
1503	 * for DMA_COMPLETE again
1504	 * Let packet complete handler take care of the packet
1505	 */
1506	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1507	if (status == DMA_COMPLETE) {
1508		spin_unlock_irqrestore(&port->lock, flags);
1509		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1510		return HRTIMER_NORESTART;
1511	}
1512
1513	/* Handle incomplete DMA receive */
1514	dmaengine_terminate_async(s->chan_rx);
1515	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1516
1517	if (read) {
1518		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1519		if (count)
1520			tty_flip_buffer_push(&port->state->port);
1521	}
1522
1523	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 
1524		sci_dma_rx_submit(s, true);
1525
1526	sci_dma_rx_reenable_irq(s);
1527
1528	spin_unlock_irqrestore(&port->lock, flags);
1529
1530	return HRTIMER_NORESTART;
1531}
1532
1533static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1534					     enum dma_transfer_direction dir)
1535{
1536	struct dma_chan *chan;
1537	struct dma_slave_config cfg;
1538	int ret;
1539
1540	chan = dma_request_slave_channel(port->dev,
1541					 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1542	if (!chan) {
1543		dev_dbg(port->dev, "dma_request_slave_channel failed\n");
1544		return NULL;
1545	}
1546
1547	memset(&cfg, 0, sizeof(cfg));
1548	cfg.direction = dir;
1549	if (dir == DMA_MEM_TO_DEV) {
1550		cfg.dst_addr = port->mapbase +
1551			(sci_getreg(port, SCxTDR)->offset << port->regshift);
1552		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1553	} else {
1554		cfg.src_addr = port->mapbase +
1555			(sci_getreg(port, SCxRDR)->offset << port->regshift);
1556		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1557	}
1558
1559	ret = dmaengine_slave_config(chan, &cfg);
1560	if (ret) {
1561		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1562		dma_release_channel(chan);
1563		return NULL;
1564	}
1565
1566	return chan;
1567}
1568
1569static void sci_request_dma(struct uart_port *port)
1570{
1571	struct sci_port *s = to_sci_port(port);
1572	struct dma_chan *chan;
1573
1574	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1575
1576	/*
1577	 * DMA on console may interfere with Kernel log messages which use
1578	 * plain putchar(). So, simply don't use it with a console.
1579	 */
1580	if (uart_console(port))
1581		return;
1582
1583	if (!port->dev->of_node)
1584		return;
1585
1586	s->cookie_tx = -EINVAL;
1587
1588	/*
1589	 * Don't request a dma channel if no channel was specified
1590	 * in the device tree.
1591	 */
1592	if (!of_find_property(port->dev->of_node, "dmas", NULL))
1593		return;
1594
1595	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1596	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1597	if (chan) {
1598		/* UART circular tx buffer is an aligned page. */
1599		s->tx_dma_addr = dma_map_single(chan->device->dev,
1600						port->state->xmit.buf,
1601						UART_XMIT_SIZE,
1602						DMA_TO_DEVICE);
1603		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1604			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1605			dma_release_channel(chan);
1606		} else {
1607			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1608				__func__, UART_XMIT_SIZE,
1609				port->state->xmit.buf, &s->tx_dma_addr);
1610
1611			INIT_WORK(&s->work_tx, sci_dma_tx_work_fn);
1612			s->chan_tx_saved = s->chan_tx = chan;
1613		}
1614	}
1615
1616	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1617	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1618	if (chan) {
1619		unsigned int i;
1620		dma_addr_t dma;
1621		void *buf;
1622
1623		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1624		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1625					 &dma, GFP_KERNEL);
1626		if (!buf) {
1627			dev_warn(port->dev,
1628				 "Failed to allocate Rx dma buffer, using PIO\n");
1629			dma_release_channel(chan);
1630			return;
1631		}
1632
1633		for (i = 0; i < 2; i++) {
1634			struct scatterlist *sg = &s->sg_rx[i];
1635
1636			sg_init_table(sg, 1);
1637			s->rx_buf[i] = buf;
1638			sg_dma_address(sg) = dma;
1639			sg_dma_len(sg) = s->buf_len_rx;
1640
1641			buf += s->buf_len_rx;
1642			dma += s->buf_len_rx;
1643		}
1644
1645		hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1646		s->rx_timer.function = sci_dma_rx_timer_fn;
1647
1648		s->chan_rx_saved = s->chan_rx = chan;
1649
1650		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 
1651			sci_dma_rx_submit(s, false);
1652	}
1653}
1654
1655static void sci_free_dma(struct uart_port *port)
1656{
1657	struct sci_port *s = to_sci_port(port);
1658
1659	if (s->chan_tx_saved)
1660		sci_dma_tx_release(s);
1661	if (s->chan_rx_saved)
1662		sci_dma_rx_release(s);
1663}
1664
1665static void sci_flush_buffer(struct uart_port *port)
1666{
1667	struct sci_port *s = to_sci_port(port);
1668
1669	/*
1670	 * In uart_flush_buffer(), the xmit circular buffer has just been
1671	 * cleared, so we have to reset tx_dma_len accordingly, and stop any
1672	 * pending transfers
1673	 */
1674	s->tx_dma_len = 0;
1675	if (s->chan_tx) {
1676		dmaengine_terminate_async(s->chan_tx);
1677		s->cookie_tx = -EINVAL;
1678	}
1679}
1680#else /* !CONFIG_SERIAL_SH_SCI_DMA */
1681static inline void sci_request_dma(struct uart_port *port)
1682{
1683}
1684
1685static inline void sci_free_dma(struct uart_port *port)
1686{
1687}
1688
1689#define sci_flush_buffer	NULL
1690#endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1691
1692static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1693{
1694	struct uart_port *port = ptr;
1695	struct sci_port *s = to_sci_port(port);
1696
1697#ifdef CONFIG_SERIAL_SH_SCI_DMA
1698	if (s->chan_rx) {
1699		u16 scr = serial_port_in(port, SCSCR);
1700		u16 ssr = serial_port_in(port, SCxSR);
1701
1702		/* Disable future Rx interrupts */
1703		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1704			disable_irq_nosync(irq);
1705			scr |= SCSCR_RDRQE;
 
 
 
 
 
 
1706		} else {
1707			if (sci_dma_rx_submit(s, false) < 0)
1708				goto handle_pio;
1709
1710			scr &= ~SCSCR_RIE;
1711		}
1712		serial_port_out(port, SCSCR, scr);
1713		/* Clear current interrupt */
1714		serial_port_out(port, SCxSR,
1715				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1716		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1717			jiffies, s->rx_timeout);
1718		start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1719
1720		return IRQ_HANDLED;
1721	}
1722
1723handle_pio:
1724#endif
1725
1726	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1727		if (!scif_rtrg_enabled(port))
1728			scif_set_rtrg(port, s->rx_trigger);
1729
1730		mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1731			  s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1732	}
1733
1734	/* I think sci_receive_chars has to be called irrespective
1735	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1736	 * to be disabled?
1737	 */
1738	sci_receive_chars(port);
1739
1740	return IRQ_HANDLED;
1741}
1742
1743static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1744{
1745	struct uart_port *port = ptr;
1746	unsigned long flags;
1747
1748	spin_lock_irqsave(&port->lock, flags);
1749	sci_transmit_chars(port);
1750	spin_unlock_irqrestore(&port->lock, flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1751
1752	return IRQ_HANDLED;
1753}
1754
1755static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1756{
1757	struct uart_port *port = ptr;
1758
1759	/* Handle BREAKs */
1760	sci_handle_breaks(port);
1761
1762	/* drop invalid character received before break was detected */
1763	serial_port_in(port, SCxRDR);
1764
1765	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1766
1767	return IRQ_HANDLED;
1768}
1769
1770static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1771{
1772	struct uart_port *port = ptr;
1773	struct sci_port *s = to_sci_port(port);
1774
1775	if (s->irqs[SCIx_ERI_IRQ] == s->irqs[SCIx_BRI_IRQ]) {
1776		/* Break and Error interrupts are muxed */
1777		unsigned short ssr_status = serial_port_in(port, SCxSR);
1778
1779		/* Break Interrupt */
1780		if (ssr_status & SCxSR_BRK(port))
1781			sci_br_interrupt(irq, ptr);
1782
1783		/* Break only? */
1784		if (!(ssr_status & SCxSR_ERRORS(port)))
1785			return IRQ_HANDLED;
1786	}
1787
1788	/* Handle errors */
1789	if (port->type == PORT_SCI) {
1790		if (sci_handle_errors(port)) {
1791			/* discard character in rx buffer */
1792			serial_port_in(port, SCxSR);
1793			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1794		}
1795	} else {
1796		sci_handle_fifo_overrun(port);
1797		if (!s->chan_rx)
1798			sci_receive_chars(port);
1799	}
1800
1801	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1802
1803	/* Kick the transmission */
1804	if (!s->chan_tx)
1805		sci_tx_interrupt(irq, ptr);
1806
1807	return IRQ_HANDLED;
1808}
1809
1810static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1811{
1812	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1813	struct uart_port *port = ptr;
1814	struct sci_port *s = to_sci_port(port);
1815	irqreturn_t ret = IRQ_NONE;
1816
1817	ssr_status = serial_port_in(port, SCxSR);
1818	scr_status = serial_port_in(port, SCSCR);
1819	if (s->params->overrun_reg == SCxSR)
1820		orer_status = ssr_status;
1821	else if (sci_getreg(port, s->params->overrun_reg)->size)
1822		orer_status = serial_port_in(port, s->params->overrun_reg);
1823
1824	err_enabled = scr_status & port_rx_irq_mask(port);
1825
1826	/* Tx Interrupt */
1827	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1828	    !s->chan_tx)
1829		ret = sci_tx_interrupt(irq, ptr);
1830
1831	/*
1832	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1833	 * DR flags
1834	 */
1835	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1836	    (scr_status & SCSCR_RIE))
1837		ret = sci_rx_interrupt(irq, ptr);
1838
1839	/* Error Interrupt */
1840	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1841		ret = sci_er_interrupt(irq, ptr);
1842
1843	/* Break Interrupt */
1844	if (s->irqs[SCIx_ERI_IRQ] != s->irqs[SCIx_BRI_IRQ] &&
1845	    (ssr_status & SCxSR_BRK(port)) && err_enabled)
1846		ret = sci_br_interrupt(irq, ptr);
1847
1848	/* Overrun Interrupt */
1849	if (orer_status & s->params->overrun_mask) {
1850		sci_handle_fifo_overrun(port);
1851		ret = IRQ_HANDLED;
1852	}
1853
1854	return ret;
1855}
1856
1857static const struct sci_irq_desc {
1858	const char	*desc;
1859	irq_handler_t	handler;
1860} sci_irq_desc[] = {
1861	/*
1862	 * Split out handlers, the default case.
1863	 */
1864	[SCIx_ERI_IRQ] = {
1865		.desc = "rx err",
1866		.handler = sci_er_interrupt,
1867	},
1868
1869	[SCIx_RXI_IRQ] = {
1870		.desc = "rx full",
1871		.handler = sci_rx_interrupt,
1872	},
1873
1874	[SCIx_TXI_IRQ] = {
1875		.desc = "tx empty",
1876		.handler = sci_tx_interrupt,
1877	},
1878
1879	[SCIx_BRI_IRQ] = {
1880		.desc = "break",
1881		.handler = sci_br_interrupt,
1882	},
1883
1884	[SCIx_DRI_IRQ] = {
1885		.desc = "rx ready",
1886		.handler = sci_rx_interrupt,
1887	},
1888
1889	[SCIx_TEI_IRQ] = {
1890		.desc = "tx end",
1891		.handler = sci_tx_interrupt,
1892	},
1893
1894	/*
1895	 * Special muxed handler.
1896	 */
1897	[SCIx_MUX_IRQ] = {
1898		.desc = "mux",
1899		.handler = sci_mpxed_interrupt,
1900	},
1901};
1902
1903static int sci_request_irq(struct sci_port *port)
1904{
1905	struct uart_port *up = &port->port;
1906	int i, j, w, ret = 0;
1907
1908	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1909		const struct sci_irq_desc *desc;
1910		int irq;
1911
1912		/* Check if already registered (muxed) */
1913		for (w = 0; w < i; w++)
1914			if (port->irqs[w] == port->irqs[i])
1915				w = i + 1;
1916		if (w > i)
1917			continue;
1918
1919		if (SCIx_IRQ_IS_MUXED(port)) {
1920			i = SCIx_MUX_IRQ;
1921			irq = up->irq;
1922		} else {
1923			irq = port->irqs[i];
1924
1925			/*
1926			 * Certain port types won't support all of the
1927			 * available interrupt sources.
1928			 */
1929			if (unlikely(irq < 0))
1930				continue;
1931		}
1932
1933		desc = sci_irq_desc + i;
1934		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1935					    dev_name(up->dev), desc->desc);
1936		if (!port->irqstr[j]) {
1937			ret = -ENOMEM;
1938			goto out_nomem;
1939		}
1940
1941		ret = request_irq(irq, desc->handler, up->irqflags,
1942				  port->irqstr[j], port);
1943		if (unlikely(ret)) {
1944			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1945			goto out_noirq;
1946		}
1947	}
1948
1949	return 0;
1950
1951out_noirq:
1952	while (--i >= 0)
1953		free_irq(port->irqs[i], port);
1954
1955out_nomem:
1956	while (--j >= 0)
1957		kfree(port->irqstr[j]);
1958
1959	return ret;
1960}
1961
1962static void sci_free_irq(struct sci_port *port)
1963{
1964	int i, j;
1965
1966	/*
1967	 * Intentionally in reverse order so we iterate over the muxed
1968	 * IRQ first.
1969	 */
1970	for (i = 0; i < SCIx_NR_IRQS; i++) {
1971		int irq = port->irqs[i];
1972
1973		/*
1974		 * Certain port types won't support all of the available
1975		 * interrupt sources.
1976		 */
1977		if (unlikely(irq < 0))
1978			continue;
1979
1980		/* Check if already freed (irq was muxed) */
1981		for (j = 0; j < i; j++)
1982			if (port->irqs[j] == irq)
1983				j = i + 1;
1984		if (j > i)
1985			continue;
1986
1987		free_irq(port->irqs[i], port);
1988		kfree(port->irqstr[i]);
1989
1990		if (SCIx_IRQ_IS_MUXED(port)) {
1991			/* If there's only one IRQ, we're done. */
1992			return;
1993		}
1994	}
1995}
1996
1997static unsigned int sci_tx_empty(struct uart_port *port)
1998{
1999	unsigned short status = serial_port_in(port, SCxSR);
2000	unsigned short in_tx_fifo = sci_txfill(port);
2001
2002	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
2003}
2004
2005static void sci_set_rts(struct uart_port *port, bool state)
2006{
2007	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2008		u16 data = serial_port_in(port, SCPDR);
2009
2010		/* Active low */
2011		if (state)
2012			data &= ~SCPDR_RTSD;
2013		else
2014			data |= SCPDR_RTSD;
2015		serial_port_out(port, SCPDR, data);
2016
2017		/* RTS# is output */
2018		serial_port_out(port, SCPCR,
2019				serial_port_in(port, SCPCR) | SCPCR_RTSC);
2020	} else if (sci_getreg(port, SCSPTR)->size) {
2021		u16 ctrl = serial_port_in(port, SCSPTR);
2022
2023		/* Active low */
2024		if (state)
2025			ctrl &= ~SCSPTR_RTSDT;
2026		else
2027			ctrl |= SCSPTR_RTSDT;
2028		serial_port_out(port, SCSPTR, ctrl);
2029	}
2030}
2031
2032static bool sci_get_cts(struct uart_port *port)
2033{
2034	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2035		/* Active low */
2036		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
2037	} else if (sci_getreg(port, SCSPTR)->size) {
2038		/* Active low */
2039		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
2040	}
2041
2042	return true;
2043}
2044
2045/*
2046 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
2047 * CTS/RTS is supported in hardware by at least one port and controlled
2048 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
2049 * handled via the ->init_pins() op, which is a bit of a one-way street,
2050 * lacking any ability to defer pin control -- this will later be
2051 * converted over to the GPIO framework).
2052 *
2053 * Other modes (such as loopback) are supported generically on certain
2054 * port types, but not others. For these it's sufficient to test for the
2055 * existence of the support register and simply ignore the port type.
2056 */
2057static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
2058{
2059	struct sci_port *s = to_sci_port(port);
2060
2061	if (mctrl & TIOCM_LOOP) {
2062		const struct plat_sci_reg *reg;
2063
2064		/*
2065		 * Standard loopback mode for SCFCR ports.
2066		 */
2067		reg = sci_getreg(port, SCFCR);
2068		if (reg->size)
2069			serial_port_out(port, SCFCR,
2070					serial_port_in(port, SCFCR) |
2071					SCFCR_LOOP);
2072	}
2073
2074	mctrl_gpio_set(s->gpios, mctrl);
2075
2076	if (!s->has_rtscts)
2077		return;
2078
2079	if (!(mctrl & TIOCM_RTS)) {
2080		/* Disable Auto RTS */
2081		serial_port_out(port, SCFCR,
2082				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
2083
2084		/* Clear RTS */
2085		sci_set_rts(port, 0);
2086	} else if (s->autorts) {
2087		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2088			/* Enable RTS# pin function */
2089			serial_port_out(port, SCPCR,
2090				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
2091		}
2092
2093		/* Enable Auto RTS */
2094		serial_port_out(port, SCFCR,
2095				serial_port_in(port, SCFCR) | SCFCR_MCE);
2096	} else {
2097		/* Set RTS */
2098		sci_set_rts(port, 1);
2099	}
2100}
2101
2102static unsigned int sci_get_mctrl(struct uart_port *port)
2103{
2104	struct sci_port *s = to_sci_port(port);
2105	struct mctrl_gpios *gpios = s->gpios;
2106	unsigned int mctrl = 0;
2107
2108	mctrl_gpio_get(gpios, &mctrl);
2109
2110	/*
2111	 * CTS/RTS is handled in hardware when supported, while nothing
2112	 * else is wired up.
2113	 */
2114	if (s->autorts) {
2115		if (sci_get_cts(port))
2116			mctrl |= TIOCM_CTS;
2117	} else if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS)) {
2118		mctrl |= TIOCM_CTS;
2119	}
2120	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR))
2121		mctrl |= TIOCM_DSR;
2122	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD))
2123		mctrl |= TIOCM_CAR;
2124
2125	return mctrl;
2126}
2127
2128static void sci_enable_ms(struct uart_port *port)
2129{
2130	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2131}
2132
2133static void sci_break_ctl(struct uart_port *port, int break_state)
2134{
2135	unsigned short scscr, scsptr;
2136	unsigned long flags;
2137
2138	/* check whether the port has SCSPTR */
2139	if (!sci_getreg(port, SCSPTR)->size) {
2140		/*
2141		 * Not supported by hardware. Most parts couple break and rx
2142		 * interrupts together, with break detection always enabled.
2143		 */
2144		return;
2145	}
2146
2147	spin_lock_irqsave(&port->lock, flags);
2148	scsptr = serial_port_in(port, SCSPTR);
2149	scscr = serial_port_in(port, SCSCR);
2150
2151	if (break_state == -1) {
2152		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2153		scscr &= ~SCSCR_TE;
2154	} else {
2155		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2156		scscr |= SCSCR_TE;
2157	}
2158
2159	serial_port_out(port, SCSPTR, scsptr);
2160	serial_port_out(port, SCSCR, scscr);
2161	spin_unlock_irqrestore(&port->lock, flags);
2162}
2163
2164static int sci_startup(struct uart_port *port)
2165{
2166	struct sci_port *s = to_sci_port(port);
2167	int ret;
2168
2169	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2170
2171	sci_request_dma(port);
2172
2173	ret = sci_request_irq(s);
2174	if (unlikely(ret < 0)) {
2175		sci_free_dma(port);
2176		return ret;
2177	}
2178
2179	return 0;
2180}
2181
2182static void sci_shutdown(struct uart_port *port)
2183{
2184	struct sci_port *s = to_sci_port(port);
2185	unsigned long flags;
2186	u16 scr;
2187
2188	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2189
2190	s->autorts = false;
2191	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2192
2193	spin_lock_irqsave(&port->lock, flags);
2194	sci_stop_rx(port);
2195	sci_stop_tx(port);
2196	/*
2197	 * Stop RX and TX, disable related interrupts, keep clock source
2198	 * and HSCIF TOT bits
2199	 */
2200	scr = serial_port_in(port, SCSCR);
2201	serial_port_out(port, SCSCR, scr &
2202			(SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2203	spin_unlock_irqrestore(&port->lock, flags);
2204
2205#ifdef CONFIG_SERIAL_SH_SCI_DMA
2206	if (s->chan_rx_saved) {
2207		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2208			port->line);
2209		hrtimer_cancel(&s->rx_timer);
2210	}
2211#endif
2212
2213	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
2214		del_timer_sync(&s->rx_fifo_timer);
2215	sci_free_irq(s);
2216	sci_free_dma(port);
2217}
2218
2219static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2220			unsigned int *srr)
2221{
2222	unsigned long freq = s->clk_rates[SCI_SCK];
2223	int err, min_err = INT_MAX;
2224	unsigned int sr;
2225
2226	if (s->port.type != PORT_HSCIF)
2227		freq *= 2;
2228
2229	for_each_sr(sr, s) {
2230		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2231		if (abs(err) >= abs(min_err))
2232			continue;
2233
2234		min_err = err;
2235		*srr = sr - 1;
2236
2237		if (!err)
2238			break;
2239	}
2240
2241	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2242		*srr + 1);
2243	return min_err;
2244}
2245
2246static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2247			unsigned long freq, unsigned int *dlr,
2248			unsigned int *srr)
2249{
2250	int err, min_err = INT_MAX;
2251	unsigned int sr, dl;
2252
2253	if (s->port.type != PORT_HSCIF)
2254		freq *= 2;
2255
2256	for_each_sr(sr, s) {
2257		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2258		dl = clamp(dl, 1U, 65535U);
2259
2260		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2261		if (abs(err) >= abs(min_err))
2262			continue;
2263
2264		min_err = err;
2265		*dlr = dl;
2266		*srr = sr - 1;
2267
2268		if (!err)
2269			break;
2270	}
2271
2272	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2273		min_err, *dlr, *srr + 1);
2274	return min_err;
2275}
2276
2277/* calculate sample rate, BRR, and clock select */
2278static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2279			  unsigned int *brr, unsigned int *srr,
2280			  unsigned int *cks)
2281{
2282	unsigned long freq = s->clk_rates[SCI_FCK];
2283	unsigned int sr, br, prediv, scrate, c;
2284	int err, min_err = INT_MAX;
2285
2286	if (s->port.type != PORT_HSCIF)
2287		freq *= 2;
2288
2289	/*
2290	 * Find the combination of sample rate and clock select with the
2291	 * smallest deviation from the desired baud rate.
2292	 * Prefer high sample rates to maximise the receive margin.
2293	 *
2294	 * M: Receive margin (%)
2295	 * N: Ratio of bit rate to clock (N = sampling rate)
2296	 * D: Clock duty (D = 0 to 1.0)
2297	 * L: Frame length (L = 9 to 12)
2298	 * F: Absolute value of clock frequency deviation
2299	 *
2300	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2301	 *      (|D - 0.5| / N * (1 + F))|
2302	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2303	 */
2304	for_each_sr(sr, s) {
2305		for (c = 0; c <= 3; c++) {
2306			/* integerized formulas from HSCIF documentation */
2307			prediv = sr * (1 << (2 * c + 1));
2308
2309			/*
2310			 * We need to calculate:
2311			 *
2312			 *     br = freq / (prediv * bps) clamped to [1..256]
2313			 *     err = freq / (br * prediv) - bps
2314			 *
2315			 * Watch out for overflow when calculating the desired
2316			 * sampling clock rate!
2317			 */
2318			if (bps > UINT_MAX / prediv)
2319				break;
2320
2321			scrate = prediv * bps;
2322			br = DIV_ROUND_CLOSEST(freq, scrate);
2323			br = clamp(br, 1U, 256U);
2324
2325			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2326			if (abs(err) >= abs(min_err))
2327				continue;
2328
2329			min_err = err;
2330			*brr = br - 1;
2331			*srr = sr - 1;
2332			*cks = c;
2333
2334			if (!err)
2335				goto found;
2336		}
2337	}
2338
2339found:
2340	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2341		min_err, *brr, *srr + 1, *cks);
2342	return min_err;
2343}
2344
2345static void sci_reset(struct uart_port *port)
2346{
2347	const struct plat_sci_reg *reg;
2348	unsigned int status;
2349	struct sci_port *s = to_sci_port(port);
2350
2351	serial_port_out(port, SCSCR, s->hscif_tot);	/* TE=0, RE=0, CKE1=0 */
2352
2353	reg = sci_getreg(port, SCFCR);
2354	if (reg->size)
2355		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2356
2357	sci_clear_SCxSR(port,
2358			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2359			SCxSR_BREAK_CLEAR(port));
2360	if (sci_getreg(port, SCLSR)->size) {
2361		status = serial_port_in(port, SCLSR);
2362		status &= ~(SCLSR_TO | SCLSR_ORER);
2363		serial_port_out(port, SCLSR, status);
2364	}
2365
2366	if (s->rx_trigger > 1) {
2367		if (s->rx_fifo_timeout) {
2368			scif_set_rtrg(port, 1);
2369			timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2370		} else {
2371			if (port->type == PORT_SCIFA ||
2372			    port->type == PORT_SCIFB)
2373				scif_set_rtrg(port, 1);
2374			else
2375				scif_set_rtrg(port, s->rx_trigger);
2376		}
2377	}
2378}
2379
2380static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2381			    struct ktermios *old)
2382{
2383	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2384	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2385	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2386	struct sci_port *s = to_sci_port(port);
2387	const struct plat_sci_reg *reg;
2388	int min_err = INT_MAX, err;
2389	unsigned long max_freq = 0;
2390	int best_clk = -1;
2391	unsigned long flags;
2392
2393	if ((termios->c_cflag & CSIZE) == CS7)
2394		smr_val |= SCSMR_CHR;
 
 
 
 
2395	if (termios->c_cflag & PARENB)
2396		smr_val |= SCSMR_PE;
2397	if (termios->c_cflag & PARODD)
2398		smr_val |= SCSMR_PE | SCSMR_ODD;
2399	if (termios->c_cflag & CSTOPB)
2400		smr_val |= SCSMR_STOP;
2401
2402	/*
2403	 * earlyprintk comes here early on with port->uartclk set to zero.
2404	 * the clock framework is not up and running at this point so here
2405	 * we assume that 115200 is the maximum baud rate. please note that
2406	 * the baud rate is not programmed during earlyprintk - it is assumed
2407	 * that the previous boot loader has enabled required clocks and
2408	 * setup the baud rate generator hardware for us already.
2409	 */
2410	if (!port->uartclk) {
2411		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2412		goto done;
2413	}
2414
2415	for (i = 0; i < SCI_NUM_CLKS; i++)
2416		max_freq = max(max_freq, s->clk_rates[i]);
2417
2418	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2419	if (!baud)
2420		goto done;
2421
2422	/*
2423	 * There can be multiple sources for the sampling clock.  Find the one
2424	 * that gives us the smallest deviation from the desired baud rate.
2425	 */
2426
2427	/* Optional Undivided External Clock */
2428	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2429	    port->type != PORT_SCIFB) {
2430		err = sci_sck_calc(s, baud, &srr1);
2431		if (abs(err) < abs(min_err)) {
2432			best_clk = SCI_SCK;
2433			scr_val = SCSCR_CKE1;
2434			sccks = SCCKS_CKS;
2435			min_err = err;
2436			srr = srr1;
2437			if (!err)
2438				goto done;
2439		}
2440	}
2441
2442	/* Optional BRG Frequency Divided External Clock */
2443	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2444		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2445				   &srr1);
2446		if (abs(err) < abs(min_err)) {
2447			best_clk = SCI_SCIF_CLK;
2448			scr_val = SCSCR_CKE1;
2449			sccks = 0;
2450			min_err = err;
2451			dl = dl1;
2452			srr = srr1;
2453			if (!err)
2454				goto done;
2455		}
2456	}
2457
2458	/* Optional BRG Frequency Divided Internal Clock */
2459	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2460		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2461				   &srr1);
2462		if (abs(err) < abs(min_err)) {
2463			best_clk = SCI_BRG_INT;
2464			scr_val = SCSCR_CKE1;
2465			sccks = SCCKS_XIN;
2466			min_err = err;
2467			dl = dl1;
2468			srr = srr1;
2469			if (!min_err)
2470				goto done;
2471		}
2472	}
2473
2474	/* Divided Functional Clock using standard Bit Rate Register */
2475	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2476	if (abs(err) < abs(min_err)) {
2477		best_clk = SCI_FCK;
2478		scr_val = 0;
2479		min_err = err;
2480		brr = brr1;
2481		srr = srr1;
2482		cks = cks1;
2483	}
2484
2485done:
2486	if (best_clk >= 0)
2487		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2488			s->clks[best_clk], baud, min_err);
2489
2490	sci_port_enable(s);
2491
2492	/*
2493	 * Program the optional External Baud Rate Generator (BRG) first.
2494	 * It controls the mux to select (H)SCK or frequency divided clock.
2495	 */
2496	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2497		serial_port_out(port, SCDL, dl);
2498		serial_port_out(port, SCCKS, sccks);
2499	}
2500
2501	spin_lock_irqsave(&port->lock, flags);
2502
2503	sci_reset(port);
2504
2505	uart_update_timeout(port, termios->c_cflag, baud);
2506
2507	/* byte size and parity */
2508	bits = tty_get_frame_size(termios->c_cflag);
2509
2510	if (sci_getreg(port, SEMR)->size)
2511		serial_port_out(port, SEMR, 0);
2512
2513	if (best_clk >= 0) {
2514		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2515			switch (srr + 1) {
2516			case 5:  smr_val |= SCSMR_SRC_5;  break;
2517			case 7:  smr_val |= SCSMR_SRC_7;  break;
2518			case 11: smr_val |= SCSMR_SRC_11; break;
2519			case 13: smr_val |= SCSMR_SRC_13; break;
2520			case 16: smr_val |= SCSMR_SRC_16; break;
2521			case 17: smr_val |= SCSMR_SRC_17; break;
2522			case 19: smr_val |= SCSMR_SRC_19; break;
2523			case 27: smr_val |= SCSMR_SRC_27; break;
2524			}
2525		smr_val |= cks;
2526		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2527		serial_port_out(port, SCSMR, smr_val);
2528		serial_port_out(port, SCBRR, brr);
2529		if (sci_getreg(port, HSSRR)->size) {
2530			unsigned int hssrr = srr | HSCIF_SRE;
2531			/* Calculate deviation from intended rate at the
2532			 * center of the last stop bit in sampling clocks.
2533			 */
2534			int last_stop = bits * 2 - 1;
2535			int deviation = DIV_ROUND_CLOSEST(min_err * last_stop *
2536							  (int)(srr + 1),
2537							  2 * (int)baud);
2538
2539			if (abs(deviation) >= 2) {
2540				/* At least two sampling clocks off at the
2541				 * last stop bit; we can increase the error
2542				 * margin by shifting the sampling point.
2543				 */
2544				int shift = clamp(deviation / 2, -8, 7);
2545
2546				hssrr |= (shift << HSCIF_SRHP_SHIFT) &
2547					 HSCIF_SRHP_MASK;
2548				hssrr |= HSCIF_SRDE;
2549			}
2550			serial_port_out(port, HSSRR, hssrr);
2551		}
2552
2553		/* Wait one bit interval */
2554		udelay((1000000 + (baud - 1)) / baud);
2555	} else {
2556		/* Don't touch the bit rate configuration */
2557		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2558		smr_val |= serial_port_in(port, SCSMR) &
2559			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2560		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2561		serial_port_out(port, SCSMR, smr_val);
2562	}
2563
2564	sci_init_pins(port, termios->c_cflag);
2565
2566	port->status &= ~UPSTAT_AUTOCTS;
2567	s->autorts = false;
2568	reg = sci_getreg(port, SCFCR);
2569	if (reg->size) {
2570		unsigned short ctrl = serial_port_in(port, SCFCR);
2571
2572		if ((port->flags & UPF_HARD_FLOW) &&
2573		    (termios->c_cflag & CRTSCTS)) {
2574			/* There is no CTS interrupt to restart the hardware */
2575			port->status |= UPSTAT_AUTOCTS;
2576			/* MCE is enabled when RTS is raised */
2577			s->autorts = true;
2578		}
2579
2580		/*
2581		 * As we've done a sci_reset() above, ensure we don't
2582		 * interfere with the FIFOs while toggling MCE. As the
2583		 * reset values could still be set, simply mask them out.
2584		 */
2585		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2586
2587		serial_port_out(port, SCFCR, ctrl);
2588	}
2589	if (port->flags & UPF_HARD_FLOW) {
2590		/* Refresh (Auto) RTS */
2591		sci_set_mctrl(port, port->mctrl);
2592	}
2593
2594	scr_val |= SCSCR_RE | SCSCR_TE |
2595		   (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
 
 
 
 
 
 
2596	serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2597	if ((srr + 1 == 5) &&
2598	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2599		/*
2600		 * In asynchronous mode, when the sampling rate is 1/5, first
2601		 * received data may become invalid on some SCIFA and SCIFB.
2602		 * To avoid this problem wait more than 1 serial data time (1
2603		 * bit time x serial data number) after setting SCSCR.RE = 1.
2604		 */
2605		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2606	}
2607
2608	/* Calculate delay for 2 DMA buffers (4 FIFO). */
2609	s->rx_frame = (10000 * bits) / (baud / 100);
2610#ifdef CONFIG_SERIAL_SH_SCI_DMA
2611	s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2612#endif
2613
2614	if ((termios->c_cflag & CREAD) != 0)
2615		sci_start_rx(port);
2616
2617	spin_unlock_irqrestore(&port->lock, flags);
2618
2619	sci_port_disable(s);
2620
2621	if (UART_ENABLE_MS(port, termios->c_cflag))
2622		sci_enable_ms(port);
2623}
2624
2625static void sci_pm(struct uart_port *port, unsigned int state,
2626		   unsigned int oldstate)
2627{
2628	struct sci_port *sci_port = to_sci_port(port);
2629
2630	switch (state) {
2631	case UART_PM_STATE_OFF:
2632		sci_port_disable(sci_port);
2633		break;
2634	default:
2635		sci_port_enable(sci_port);
2636		break;
2637	}
2638}
2639
2640static const char *sci_type(struct uart_port *port)
2641{
2642	switch (port->type) {
2643	case PORT_IRDA:
2644		return "irda";
2645	case PORT_SCI:
2646		return "sci";
2647	case PORT_SCIF:
2648		return "scif";
2649	case PORT_SCIFA:
2650		return "scifa";
2651	case PORT_SCIFB:
2652		return "scifb";
2653	case PORT_HSCIF:
2654		return "hscif";
2655	}
2656
2657	return NULL;
2658}
2659
2660static int sci_remap_port(struct uart_port *port)
2661{
2662	struct sci_port *sport = to_sci_port(port);
2663
2664	/*
2665	 * Nothing to do if there's already an established membase.
2666	 */
2667	if (port->membase)
2668		return 0;
2669
2670	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2671		port->membase = ioremap(port->mapbase, sport->reg_size);
2672		if (unlikely(!port->membase)) {
2673			dev_err(port->dev, "can't remap port#%d\n", port->line);
2674			return -ENXIO;
2675		}
2676	} else {
2677		/*
2678		 * For the simple (and majority of) cases where we don't
2679		 * need to do any remapping, just cast the cookie
2680		 * directly.
2681		 */
2682		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2683	}
2684
2685	return 0;
2686}
2687
2688static void sci_release_port(struct uart_port *port)
2689{
2690	struct sci_port *sport = to_sci_port(port);
2691
2692	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2693		iounmap(port->membase);
2694		port->membase = NULL;
2695	}
2696
2697	release_mem_region(port->mapbase, sport->reg_size);
2698}
2699
2700static int sci_request_port(struct uart_port *port)
2701{
2702	struct resource *res;
2703	struct sci_port *sport = to_sci_port(port);
2704	int ret;
2705
2706	res = request_mem_region(port->mapbase, sport->reg_size,
2707				 dev_name(port->dev));
2708	if (unlikely(res == NULL)) {
2709		dev_err(port->dev, "request_mem_region failed.");
2710		return -EBUSY;
2711	}
2712
2713	ret = sci_remap_port(port);
2714	if (unlikely(ret != 0)) {
2715		release_resource(res);
2716		return ret;
2717	}
2718
2719	return 0;
2720}
2721
2722static void sci_config_port(struct uart_port *port, int flags)
2723{
2724	if (flags & UART_CONFIG_TYPE) {
2725		struct sci_port *sport = to_sci_port(port);
2726
2727		port->type = sport->cfg->type;
2728		sci_request_port(port);
2729	}
2730}
2731
2732static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2733{
2734	if (ser->baud_base < 2400)
2735		/* No paper tape reader for Mitch.. */
2736		return -EINVAL;
2737
2738	return 0;
2739}
2740
2741static const struct uart_ops sci_uart_ops = {
2742	.tx_empty	= sci_tx_empty,
2743	.set_mctrl	= sci_set_mctrl,
2744	.get_mctrl	= sci_get_mctrl,
2745	.start_tx	= sci_start_tx,
2746	.stop_tx	= sci_stop_tx,
2747	.stop_rx	= sci_stop_rx,
2748	.enable_ms	= sci_enable_ms,
2749	.break_ctl	= sci_break_ctl,
2750	.startup	= sci_startup,
2751	.shutdown	= sci_shutdown,
2752	.flush_buffer	= sci_flush_buffer,
2753	.set_termios	= sci_set_termios,
2754	.pm		= sci_pm,
2755	.type		= sci_type,
2756	.release_port	= sci_release_port,
2757	.request_port	= sci_request_port,
2758	.config_port	= sci_config_port,
2759	.verify_port	= sci_verify_port,
2760#ifdef CONFIG_CONSOLE_POLL
2761	.poll_get_char	= sci_poll_get_char,
2762	.poll_put_char	= sci_poll_put_char,
2763#endif
2764};
2765
2766static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2767{
2768	const char *clk_names[] = {
2769		[SCI_FCK] = "fck",
2770		[SCI_SCK] = "sck",
2771		[SCI_BRG_INT] = "brg_int",
2772		[SCI_SCIF_CLK] = "scif_clk",
2773	};
2774	struct clk *clk;
2775	unsigned int i;
2776
2777	if (sci_port->cfg->type == PORT_HSCIF)
2778		clk_names[SCI_SCK] = "hsck";
2779
2780	for (i = 0; i < SCI_NUM_CLKS; i++) {
2781		clk = devm_clk_get(dev, clk_names[i]);
2782		if (PTR_ERR(clk) == -EPROBE_DEFER)
2783			return -EPROBE_DEFER;
2784
2785		if (IS_ERR(clk) && i == SCI_FCK) {
2786			/*
2787			 * "fck" used to be called "sci_ick", and we need to
2788			 * maintain DT backward compatibility.
2789			 */
2790			clk = devm_clk_get(dev, "sci_ick");
2791			if (PTR_ERR(clk) == -EPROBE_DEFER)
2792				return -EPROBE_DEFER;
2793
2794			if (!IS_ERR(clk))
2795				goto found;
2796
 
2797			/*
2798			 * Not all SH platforms declare a clock lookup entry
2799			 * for SCI devices, in which case we need to get the
2800			 * global "peripheral_clk" clock.
2801			 */
2802			clk = devm_clk_get(dev, "peripheral_clk");
2803			if (!IS_ERR(clk))
2804				goto found;
2805
2806			dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2807				PTR_ERR(clk));
2808			return PTR_ERR(clk);
2809		}
2810
2811found:
2812		if (IS_ERR(clk))
2813			dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2814				PTR_ERR(clk));
2815		else
2816			dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
2817				clk, clk_get_rate(clk));
2818		sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2819	}
2820	return 0;
2821}
2822
2823static const struct sci_port_params *
2824sci_probe_regmap(const struct plat_sci_port *cfg)
2825{
2826	unsigned int regtype;
2827
2828	if (cfg->regtype != SCIx_PROBE_REGTYPE)
2829		return &sci_port_params[cfg->regtype];
2830
2831	switch (cfg->type) {
2832	case PORT_SCI:
2833		regtype = SCIx_SCI_REGTYPE;
2834		break;
2835	case PORT_IRDA:
2836		regtype = SCIx_IRDA_REGTYPE;
2837		break;
2838	case PORT_SCIFA:
2839		regtype = SCIx_SCIFA_REGTYPE;
2840		break;
2841	case PORT_SCIFB:
2842		regtype = SCIx_SCIFB_REGTYPE;
2843		break;
2844	case PORT_SCIF:
2845		/*
2846		 * The SH-4 is a bit of a misnomer here, although that's
2847		 * where this particular port layout originated. This
2848		 * configuration (or some slight variation thereof)
2849		 * remains the dominant model for all SCIFs.
2850		 */
2851		regtype = SCIx_SH4_SCIF_REGTYPE;
2852		break;
2853	case PORT_HSCIF:
2854		regtype = SCIx_HSCIF_REGTYPE;
2855		break;
2856	default:
2857		pr_err("Can't probe register map for given port\n");
2858		return NULL;
2859	}
2860
2861	return &sci_port_params[regtype];
2862}
2863
2864static int sci_init_single(struct platform_device *dev,
2865			   struct sci_port *sci_port, unsigned int index,
2866			   const struct plat_sci_port *p, bool early)
2867{
2868	struct uart_port *port = &sci_port->port;
2869	const struct resource *res;
2870	unsigned int i;
2871	int ret;
2872
2873	sci_port->cfg	= p;
2874
2875	port->ops	= &sci_uart_ops;
2876	port->iotype	= UPIO_MEM;
2877	port->line	= index;
2878	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_SH_SCI_CONSOLE);
2879
2880	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2881	if (res == NULL)
2882		return -ENOMEM;
2883
2884	port->mapbase = res->start;
2885	sci_port->reg_size = resource_size(res);
2886
2887	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) {
2888		if (i)
2889			sci_port->irqs[i] = platform_get_irq_optional(dev, i);
2890		else
2891			sci_port->irqs[i] = platform_get_irq(dev, i);
2892	}
2893
 
 
 
 
 
 
 
2894	/* The SCI generates several interrupts. They can be muxed together or
2895	 * connected to different interrupt lines. In the muxed case only one
2896	 * interrupt resource is specified as there is only one interrupt ID.
2897	 * In the non-muxed case, up to 6 interrupt signals might be generated
2898	 * from the SCI, however those signals might have their own individual
2899	 * interrupt ID numbers, or muxed together with another interrupt.
2900	 */
2901	if (sci_port->irqs[0] < 0)
2902		return -ENXIO;
2903
2904	if (sci_port->irqs[1] < 0)
2905		for (i = 1; i < ARRAY_SIZE(sci_port->irqs); i++)
2906			sci_port->irqs[i] = sci_port->irqs[0];
2907
2908	sci_port->params = sci_probe_regmap(p);
2909	if (unlikely(sci_port->params == NULL))
2910		return -EINVAL;
2911
2912	switch (p->type) {
2913	case PORT_SCIFB:
2914		sci_port->rx_trigger = 48;
2915		break;
2916	case PORT_HSCIF:
2917		sci_port->rx_trigger = 64;
2918		break;
2919	case PORT_SCIFA:
2920		sci_port->rx_trigger = 32;
2921		break;
2922	case PORT_SCIF:
2923		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2924			/* RX triggering not implemented for this IP */
2925			sci_port->rx_trigger = 1;
2926		else
2927			sci_port->rx_trigger = 8;
2928		break;
2929	default:
2930		sci_port->rx_trigger = 1;
2931		break;
2932	}
2933
2934	sci_port->rx_fifo_timeout = 0;
2935	sci_port->hscif_tot = 0;
2936
2937	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2938	 * match the SoC datasheet, this should be investigated. Let platform
2939	 * data override the sampling rate for now.
2940	 */
2941	sci_port->sampling_rate_mask = p->sampling_rate
2942				     ? SCI_SR(p->sampling_rate)
2943				     : sci_port->params->sampling_rate_mask;
2944
2945	if (!early) {
2946		ret = sci_init_clocks(sci_port, &dev->dev);
2947		if (ret < 0)
2948			return ret;
2949
2950		port->dev = &dev->dev;
2951
2952		pm_runtime_enable(&dev->dev);
2953	}
2954
2955	port->type		= p->type;
2956	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2957	port->fifosize		= sci_port->params->fifosize;
2958
2959	if (port->type == PORT_SCI) {
2960		if (sci_port->reg_size >= 0x20)
2961			port->regshift = 2;
2962		else
2963			port->regshift = 1;
2964	}
2965
2966	/*
2967	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2968	 * for the multi-IRQ ports, which is where we are primarily
2969	 * concerned with the shutdown path synchronization.
2970	 *
2971	 * For the muxed case there's nothing more to do.
2972	 */
2973	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
2974	port->irqflags		= 0;
2975
2976	port->serial_in		= sci_serial_in;
2977	port->serial_out	= sci_serial_out;
2978
2979	return 0;
2980}
2981
2982static void sci_cleanup_single(struct sci_port *port)
2983{
2984	pm_runtime_disable(port->port.dev);
2985}
2986
2987#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2988    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2989static void serial_console_putchar(struct uart_port *port, int ch)
2990{
2991	sci_poll_put_char(port, ch);
2992}
2993
2994/*
2995 *	Print a string to the serial port trying not to disturb
2996 *	any possible real use of the port...
2997 */
2998static void serial_console_write(struct console *co, const char *s,
2999				 unsigned count)
3000{
3001	struct sci_port *sci_port = &sci_ports[co->index];
3002	struct uart_port *port = &sci_port->port;
3003	unsigned short bits, ctrl, ctrl_temp;
3004	unsigned long flags;
3005	int locked = 1;
3006
3007	if (port->sysrq)
3008		locked = 0;
3009	else if (oops_in_progress)
3010		locked = spin_trylock_irqsave(&port->lock, flags);
3011	else
3012		spin_lock_irqsave(&port->lock, flags);
3013
3014	/* first save SCSCR then disable interrupts, keep clock source */
3015	ctrl = serial_port_in(port, SCSCR);
3016	ctrl_temp = SCSCR_RE | SCSCR_TE |
3017		    (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
3018		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
3019	serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
3020
3021	uart_console_write(port, s, count, serial_console_putchar);
3022
3023	/* wait until fifo is empty and last bit has been transmitted */
3024	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
3025	while ((serial_port_in(port, SCxSR) & bits) != bits)
3026		cpu_relax();
3027
3028	/* restore the SCSCR */
3029	serial_port_out(port, SCSCR, ctrl);
3030
3031	if (locked)
3032		spin_unlock_irqrestore(&port->lock, flags);
3033}
3034
3035static int serial_console_setup(struct console *co, char *options)
3036{
3037	struct sci_port *sci_port;
3038	struct uart_port *port;
3039	int baud = 115200;
3040	int bits = 8;
3041	int parity = 'n';
3042	int flow = 'n';
3043	int ret;
3044
3045	/*
3046	 * Refuse to handle any bogus ports.
3047	 */
3048	if (co->index < 0 || co->index >= SCI_NPORTS)
3049		return -ENODEV;
3050
3051	sci_port = &sci_ports[co->index];
3052	port = &sci_port->port;
3053
3054	/*
3055	 * Refuse to handle uninitialized ports.
3056	 */
3057	if (!port->ops)
3058		return -ENODEV;
3059
3060	ret = sci_remap_port(port);
3061	if (unlikely(ret != 0))
3062		return ret;
3063
3064	if (options)
3065		uart_parse_options(options, &baud, &parity, &bits, &flow);
3066
3067	return uart_set_options(port, co, baud, parity, bits, flow);
3068}
3069
3070static struct console serial_console = {
3071	.name		= "ttySC",
3072	.device		= uart_console_device,
3073	.write		= serial_console_write,
3074	.setup		= serial_console_setup,
3075	.flags		= CON_PRINTBUFFER,
3076	.index		= -1,
3077	.data		= &sci_uart_driver,
3078};
3079
3080#ifdef CONFIG_SUPERH
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3081static struct console early_serial_console = {
3082	.name           = "early_ttySC",
3083	.write          = serial_console_write,
 
3084	.flags          = CON_PRINTBUFFER,
3085	.index		= -1,
3086};
3087
3088static char early_serial_buf[32];
3089
3090static int sci_probe_earlyprintk(struct platform_device *pdev)
3091{
3092	const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
3093
3094	if (early_serial_console.data)
3095		return -EEXIST;
3096
3097	early_serial_console.index = pdev->id;
3098
3099	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
3100
3101	serial_console_setup(&early_serial_console, early_serial_buf);
3102
3103	if (!strstr(early_serial_buf, "keep"))
3104		early_serial_console.flags |= CON_BOOT;
3105
3106	register_console(&early_serial_console);
3107	return 0;
3108}
3109#endif
3110
3111#define SCI_CONSOLE	(&serial_console)
3112
3113#else
3114static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3115{
3116	return -EINVAL;
3117}
3118
3119#define SCI_CONSOLE	NULL
3120
3121#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3122
3123static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3124
3125static DEFINE_MUTEX(sci_uart_registration_lock);
3126static struct uart_driver sci_uart_driver = {
3127	.owner		= THIS_MODULE,
3128	.driver_name	= "sci",
3129	.dev_name	= "ttySC",
3130	.major		= SCI_MAJOR,
3131	.minor		= SCI_MINOR_START,
3132	.nr		= SCI_NPORTS,
3133	.cons		= SCI_CONSOLE,
3134};
3135
3136static int sci_remove(struct platform_device *dev)
3137{
3138	struct sci_port *port = platform_get_drvdata(dev);
3139	unsigned int type = port->port.type;	/* uart_remove_... clears it */
3140
3141	sci_ports_in_use &= ~BIT(port->port.line);
3142	uart_remove_one_port(&sci_uart_driver, &port->port);
3143
3144	sci_cleanup_single(port);
3145
3146	if (port->port.fifosize > 1)
3147		device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3148	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
3149		device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
3150
3151	return 0;
3152}
3153
3154
3155#define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
3156#define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
3157#define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
3158
3159static const struct of_device_id of_sci_match[] = {
3160	/* SoC-specific types */
3161	{
3162		.compatible = "renesas,scif-r7s72100",
3163		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3164	},
3165	{
3166		.compatible = "renesas,scif-r7s9210",
3167		.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3168	},
3169	{
3170		.compatible = "renesas,scif-r9a07g044",
3171		.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3172	},
3173	/* Family-specific types */
3174	{
3175		.compatible = "renesas,rcar-gen1-scif",
3176		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3177	}, {
3178		.compatible = "renesas,rcar-gen2-scif",
3179		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3180	}, {
3181		.compatible = "renesas,rcar-gen3-scif",
3182		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
 
 
 
3183	},
3184	/* Generic types */
3185	{
3186		.compatible = "renesas,scif",
3187		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3188	}, {
3189		.compatible = "renesas,scifa",
3190		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3191	}, {
3192		.compatible = "renesas,scifb",
3193		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3194	}, {
3195		.compatible = "renesas,hscif",
3196		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3197	}, {
3198		.compatible = "renesas,sci",
3199		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3200	}, {
3201		/* Terminator */
3202	},
3203};
3204MODULE_DEVICE_TABLE(of, of_sci_match);
3205
 
 
 
 
 
3206static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3207					  unsigned int *dev_id)
3208{
3209	struct device_node *np = pdev->dev.of_node;
 
3210	struct plat_sci_port *p;
3211	struct sci_port *sp;
3212	const void *data;
3213	int id;
3214
3215	if (!IS_ENABLED(CONFIG_OF) || !np)
3216		return NULL;
3217
3218	data = of_device_get_match_data(&pdev->dev);
3219
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3220	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3221	if (!p)
3222		return NULL;
3223
3224	/* Get the line number from the aliases node. */
3225	id = of_alias_get_id(np, "serial");
3226	if (id < 0 && ~sci_ports_in_use)
3227		id = ffz(sci_ports_in_use);
3228	if (id < 0) {
3229		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3230		return NULL;
3231	}
3232	if (id >= ARRAY_SIZE(sci_ports)) {
3233		dev_err(&pdev->dev, "serial%d out of range\n", id);
3234		return NULL;
3235	}
3236
3237	sp = &sci_ports[id];
3238	*dev_id = id;
3239
3240	p->type = SCI_OF_TYPE(data);
3241	p->regtype = SCI_OF_REGTYPE(data);
3242
3243	sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3244
3245	return p;
3246}
3247
3248static int sci_probe_single(struct platform_device *dev,
3249				      unsigned int index,
3250				      struct plat_sci_port *p,
3251				      struct sci_port *sciport)
3252{
3253	int ret;
3254
3255	/* Sanity check */
3256	if (unlikely(index >= SCI_NPORTS)) {
3257		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3258			   index+1, SCI_NPORTS);
3259		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3260		return -EINVAL;
3261	}
3262	BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
3263	if (sci_ports_in_use & BIT(index))
3264		return -EBUSY;
3265
3266	mutex_lock(&sci_uart_registration_lock);
3267	if (!sci_uart_driver.state) {
3268		ret = uart_register_driver(&sci_uart_driver);
3269		if (ret) {
3270			mutex_unlock(&sci_uart_registration_lock);
3271			return ret;
3272		}
3273	}
3274	mutex_unlock(&sci_uart_registration_lock);
3275
3276	ret = sci_init_single(dev, sciport, index, p, false);
3277	if (ret)
3278		return ret;
3279
3280	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3281	if (IS_ERR(sciport->gpios))
3282		return PTR_ERR(sciport->gpios);
3283
3284	if (sciport->has_rtscts) {
3285		if (mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_CTS) ||
3286		    mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_RTS)) {
3287			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3288			return -EINVAL;
3289		}
3290		sciport->port.flags |= UPF_HARD_FLOW;
3291	}
3292
3293	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3294	if (ret) {
3295		sci_cleanup_single(sciport);
3296		return ret;
3297	}
3298
3299	return 0;
3300}
3301
3302static int sci_probe(struct platform_device *dev)
3303{
3304	struct plat_sci_port *p;
3305	struct sci_port *sp;
3306	unsigned int dev_id;
3307	int ret;
3308
3309	/*
3310	 * If we've come here via earlyprintk initialization, head off to
3311	 * the special early probe. We don't have sufficient device state
3312	 * to make it beyond this yet.
3313	 */
3314#ifdef CONFIG_SUPERH
3315	if (is_sh_early_platform_device(dev))
3316		return sci_probe_earlyprintk(dev);
3317#endif
3318
3319	if (dev->dev.of_node) {
3320		p = sci_parse_dt(dev, &dev_id);
3321		if (p == NULL)
3322			return -EINVAL;
3323	} else {
3324		p = dev->dev.platform_data;
3325		if (p == NULL) {
3326			dev_err(&dev->dev, "no platform data supplied\n");
3327			return -EINVAL;
3328		}
3329
3330		dev_id = dev->id;
3331	}
3332
3333	sp = &sci_ports[dev_id];
3334	platform_set_drvdata(dev, sp);
3335
3336	ret = sci_probe_single(dev, dev_id, p, sp);
3337	if (ret)
3338		return ret;
3339
3340	if (sp->port.fifosize > 1) {
3341		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3342		if (ret)
3343			return ret;
3344	}
3345	if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3346	    sp->port.type == PORT_HSCIF) {
3347		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
3348		if (ret) {
3349			if (sp->port.fifosize > 1) {
3350				device_remove_file(&dev->dev,
3351						   &dev_attr_rx_fifo_trigger);
3352			}
3353			return ret;
3354		}
3355	}
3356
3357#ifdef CONFIG_SH_STANDARD_BIOS
3358	sh_bios_gdb_detach();
3359#endif
3360
3361	sci_ports_in_use |= BIT(dev_id);
3362	return 0;
3363}
3364
3365static __maybe_unused int sci_suspend(struct device *dev)
3366{
3367	struct sci_port *sport = dev_get_drvdata(dev);
3368
3369	if (sport)
3370		uart_suspend_port(&sci_uart_driver, &sport->port);
3371
3372	return 0;
3373}
3374
3375static __maybe_unused int sci_resume(struct device *dev)
3376{
3377	struct sci_port *sport = dev_get_drvdata(dev);
3378
3379	if (sport)
3380		uart_resume_port(&sci_uart_driver, &sport->port);
3381
3382	return 0;
3383}
3384
3385static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3386
3387static struct platform_driver sci_driver = {
3388	.probe		= sci_probe,
3389	.remove		= sci_remove,
3390	.driver		= {
3391		.name	= "sh-sci",
3392		.pm	= &sci_dev_pm_ops,
3393		.of_match_table = of_match_ptr(of_sci_match),
3394	},
3395};
3396
3397static int __init sci_init(void)
3398{
3399	pr_info("%s\n", banner);
3400
3401	return platform_driver_register(&sci_driver);
3402}
3403
3404static void __exit sci_exit(void)
3405{
3406	platform_driver_unregister(&sci_driver);
3407
3408	if (sci_uart_driver.state)
3409		uart_unregister_driver(&sci_uart_driver);
3410}
3411
3412#if defined(CONFIG_SUPERH) && defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
3413sh_early_platform_init_buffer("earlyprintk", &sci_driver,
3414			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3415#endif
3416#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3417static struct plat_sci_port port_cfg __initdata;
3418
3419static int __init early_console_setup(struct earlycon_device *device,
3420				      int type)
3421{
3422	if (!device->port.membase)
3423		return -ENODEV;
3424
3425	device->port.serial_in = sci_serial_in;
3426	device->port.serial_out	= sci_serial_out;
3427	device->port.type = type;
3428	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3429	port_cfg.type = type;
3430	sci_ports[0].cfg = &port_cfg;
3431	sci_ports[0].params = sci_probe_regmap(&port_cfg);
3432	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3433	sci_serial_out(&sci_ports[0].port, SCSCR,
3434		       SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3435
3436	device->con->write = serial_console_write;
3437	return 0;
3438}
3439static int __init sci_early_console_setup(struct earlycon_device *device,
3440					  const char *opt)
3441{
3442	return early_console_setup(device, PORT_SCI);
3443}
3444static int __init scif_early_console_setup(struct earlycon_device *device,
3445					  const char *opt)
3446{
3447	return early_console_setup(device, PORT_SCIF);
3448}
3449static int __init rzscifa_early_console_setup(struct earlycon_device *device,
3450					  const char *opt)
3451{
3452	port_cfg.regtype = SCIx_RZ_SCIFA_REGTYPE;
3453	return early_console_setup(device, PORT_SCIF);
3454}
3455
3456static int __init scifa_early_console_setup(struct earlycon_device *device,
3457					  const char *opt)
3458{
3459	return early_console_setup(device, PORT_SCIFA);
3460}
3461static int __init scifb_early_console_setup(struct earlycon_device *device,
3462					  const char *opt)
3463{
3464	return early_console_setup(device, PORT_SCIFB);
3465}
3466static int __init hscif_early_console_setup(struct earlycon_device *device,
3467					  const char *opt)
3468{
3469	return early_console_setup(device, PORT_HSCIF);
3470}
3471
3472OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3473OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3474OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rzscifa_early_console_setup);
3475OF_EARLYCON_DECLARE(scif, "renesas,scif-r9a07g044", rzscifa_early_console_setup);
3476OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3477OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3478OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3479#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3480
3481module_init(sci_init);
3482module_exit(sci_exit);
3483
3484MODULE_LICENSE("GPL");
3485MODULE_ALIAS("platform:sh-sci");
3486MODULE_AUTHOR("Paul Mundt");
3487MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");