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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");
v4.10.11
 
   1/*
   2 * SuperH on-chip serial module support.  (SCI with no FIFO / with FIFO)
   3 *
   4 *  Copyright (C) 2002 - 2011  Paul Mundt
   5 *  Copyright (C) 2015 Glider bvba
   6 *  Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
   7 *
   8 * based off of the old drivers/char/sh-sci.c by:
   9 *
  10 *   Copyright (C) 1999, 2000  Niibe Yutaka
  11 *   Copyright (C) 2000  Sugioka Toshinobu
  12 *   Modified to support multiple serial ports. Stuart Menefy (May 2000).
  13 *   Modified to support SecureEdge. David McCullough (2002)
  14 *   Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
  15 *   Removed SH7300 support (Jul 2007).
  16 *
  17 * This file is subject to the terms and conditions of the GNU General Public
  18 * License.  See the file "COPYING" in the main directory of this archive
  19 * for more details.
  20 */
  21#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  22#define SUPPORT_SYSRQ
  23#endif
  24
  25#undef DEBUG
  26
  27#include <linux/clk.h>
  28#include <linux/console.h>
  29#include <linux/ctype.h>
  30#include <linux/cpufreq.h>
  31#include <linux/delay.h>
  32#include <linux/dmaengine.h>
  33#include <linux/dma-mapping.h>
  34#include <linux/err.h>
  35#include <linux/errno.h>
  36#include <linux/init.h>
  37#include <linux/interrupt.h>
  38#include <linux/ioport.h>
 
  39#include <linux/major.h>
 
  40#include <linux/module.h>
  41#include <linux/mm.h>
  42#include <linux/of.h>
  43#include <linux/platform_device.h>
  44#include <linux/pm_runtime.h>
 
  45#include <linux/scatterlist.h>
  46#include <linux/serial.h>
  47#include <linux/serial_sci.h>
  48#include <linux/sh_dma.h>
  49#include <linux/slab.h>
  50#include <linux/string.h>
  51#include <linux/sysrq.h>
  52#include <linux/timer.h>
  53#include <linux/tty.h>
  54#include <linux/tty_flip.h>
  55
  56#ifdef CONFIG_SUPERH
  57#include <asm/sh_bios.h>
 
  58#endif
  59
  60#include "serial_mctrl_gpio.h"
  61#include "sh-sci.h"
  62
  63/* Offsets into the sci_port->irqs array */
  64enum {
  65	SCIx_ERI_IRQ,
  66	SCIx_RXI_IRQ,
  67	SCIx_TXI_IRQ,
  68	SCIx_BRI_IRQ,
 
 
  69	SCIx_NR_IRQS,
  70
  71	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
  72};
  73
  74#define SCIx_IRQ_IS_MUXED(port)			\
  75	((port)->irqs[SCIx_ERI_IRQ] ==	\
  76	 (port)->irqs[SCIx_RXI_IRQ]) ||	\
  77	((port)->irqs[SCIx_ERI_IRQ] &&	\
  78	 ((port)->irqs[SCIx_RXI_IRQ] < 0))
  79
  80enum SCI_CLKS {
  81	SCI_FCK,		/* Functional Clock */
  82	SCI_SCK,		/* Optional External Clock */
  83	SCI_BRG_INT,		/* Optional BRG Internal Clock Source */
  84	SCI_SCIF_CLK,		/* Optional BRG External Clock Source */
  85	SCI_NUM_CLKS
  86};
  87
  88/* Bit x set means sampling rate x + 1 is supported */
  89#define SCI_SR(x)		BIT((x) - 1)
  90#define SCI_SR_RANGE(x, y)	GENMASK((y) - 1, (x) - 1)
  91
  92#define SCI_SR_SCIFAB		SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
  93				SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
  94				SCI_SR(19) | SCI_SR(27)
  95
  96#define min_sr(_port)		ffs((_port)->sampling_rate_mask)
  97#define max_sr(_port)		fls((_port)->sampling_rate_mask)
  98
  99/* Iterate over all supported sampling rates, from high to low */
 100#define for_each_sr(_sr, _port)						\
 101	for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--)	\
 102		if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
 103
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 104struct sci_port {
 105	struct uart_port	port;
 106
 107	/* Platform configuration */
 108	struct plat_sci_port	*cfg;
 109	unsigned int		overrun_reg;
 110	unsigned int		overrun_mask;
 111	unsigned int		error_mask;
 112	unsigned int		error_clear;
 113	unsigned int		sampling_rate_mask;
 114	resource_size_t		reg_size;
 115	struct mctrl_gpios	*gpios;
 116
 117	/* Break timer */
 118	struct timer_list	break_timer;
 119	int			break_flag;
 120
 121	/* Clocks */
 122	struct clk		*clks[SCI_NUM_CLKS];
 123	unsigned long		clk_rates[SCI_NUM_CLKS];
 124
 125	int			irqs[SCIx_NR_IRQS];
 126	char			*irqstr[SCIx_NR_IRQS];
 127
 128	struct dma_chan			*chan_tx;
 129	struct dma_chan			*chan_rx;
 130
 131#ifdef CONFIG_SERIAL_SH_SCI_DMA
 
 
 132	dma_cookie_t			cookie_tx;
 133	dma_cookie_t			cookie_rx[2];
 134	dma_cookie_t			active_rx;
 135	dma_addr_t			tx_dma_addr;
 136	unsigned int			tx_dma_len;
 137	struct scatterlist		sg_rx[2];
 138	void				*rx_buf[2];
 139	size_t				buf_len_rx;
 140	struct work_struct		work_tx;
 141	struct timer_list		rx_timer;
 142	unsigned int			rx_timeout;
 143#endif
 
 
 
 
 
 144
 
 145	bool autorts;
 146};
 147
 148#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
 149
 150static struct sci_port sci_ports[SCI_NPORTS];
 
 151static struct uart_driver sci_uart_driver;
 152
 153static inline struct sci_port *
 154to_sci_port(struct uart_port *uart)
 155{
 156	return container_of(uart, struct sci_port, port);
 157}
 158
 159struct plat_sci_reg {
 160	u8 offset, size;
 161};
 162
 163/* Helper for invalidating specific entries of an inherited map. */
 164#define sci_reg_invalid	{ .offset = 0, .size = 0 }
 165
 166static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
 167	[SCIx_PROBE_REGTYPE] = {
 168		[0 ... SCIx_NR_REGS - 1] = sci_reg_invalid,
 169	},
 170
 171	/*
 172	 * Common SCI definitions, dependent on the port's regshift
 173	 * value.
 174	 */
 175	[SCIx_SCI_REGTYPE] = {
 176		[SCSMR]		= { 0x00,  8 },
 177		[SCBRR]		= { 0x01,  8 },
 178		[SCSCR]		= { 0x02,  8 },
 179		[SCxTDR]	= { 0x03,  8 },
 180		[SCxSR]		= { 0x04,  8 },
 181		[SCxRDR]	= { 0x05,  8 },
 182		[SCFCR]		= sci_reg_invalid,
 183		[SCFDR]		= sci_reg_invalid,
 184		[SCTFDR]	= sci_reg_invalid,
 185		[SCRFDR]	= sci_reg_invalid,
 186		[SCSPTR]	= sci_reg_invalid,
 187		[SCLSR]		= sci_reg_invalid,
 188		[HSSRR]		= sci_reg_invalid,
 189		[SCPCR]		= sci_reg_invalid,
 190		[SCPDR]		= sci_reg_invalid,
 191		[SCDL]		= sci_reg_invalid,
 192		[SCCKS]		= sci_reg_invalid,
 193	},
 194
 195	/*
 196	 * Common definitions for legacy IrDA ports, dependent on
 197	 * regshift value.
 198	 */
 199	[SCIx_IRDA_REGTYPE] = {
 200		[SCSMR]		= { 0x00,  8 },
 201		[SCBRR]		= { 0x01,  8 },
 202		[SCSCR]		= { 0x02,  8 },
 203		[SCxTDR]	= { 0x03,  8 },
 204		[SCxSR]		= { 0x04,  8 },
 205		[SCxRDR]	= { 0x05,  8 },
 206		[SCFCR]		= { 0x06,  8 },
 207		[SCFDR]		= { 0x07, 16 },
 208		[SCTFDR]	= sci_reg_invalid,
 209		[SCRFDR]	= sci_reg_invalid,
 210		[SCSPTR]	= sci_reg_invalid,
 211		[SCLSR]		= sci_reg_invalid,
 212		[HSSRR]		= sci_reg_invalid,
 213		[SCPCR]		= sci_reg_invalid,
 214		[SCPDR]		= sci_reg_invalid,
 215		[SCDL]		= sci_reg_invalid,
 216		[SCCKS]		= sci_reg_invalid,
 217	},
 218
 219	/*
 220	 * Common SCIFA definitions.
 221	 */
 222	[SCIx_SCIFA_REGTYPE] = {
 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		[SCTFDR]	= sci_reg_invalid,
 232		[SCRFDR]	= sci_reg_invalid,
 233		[SCSPTR]	= sci_reg_invalid,
 234		[SCLSR]		= sci_reg_invalid,
 235		[HSSRR]		= sci_reg_invalid,
 236		[SCPCR]		= { 0x30, 16 },
 237		[SCPDR]		= { 0x34, 16 },
 238		[SCDL]		= sci_reg_invalid,
 239		[SCCKS]		= sci_reg_invalid,
 
 240	},
 241
 242	/*
 243	 * Common SCIFB definitions.
 244	 */
 245	[SCIx_SCIFB_REGTYPE] = {
 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		[SCFDR]		= sci_reg_invalid,
 254		[SCTFDR]	= { 0x38, 16 },
 255		[SCRFDR]	= { 0x3c, 16 },
 256		[SCSPTR]	= sci_reg_invalid,
 257		[SCLSR]		= sci_reg_invalid,
 258		[HSSRR]		= sci_reg_invalid,
 259		[SCPCR]		= { 0x30, 16 },
 260		[SCPDR]		= { 0x34, 16 },
 261		[SCDL]		= sci_reg_invalid,
 262		[SCCKS]		= sci_reg_invalid,
 
 
 263	},
 264
 265	/*
 266	 * Common SH-2(A) SCIF definitions for ports with FIFO data
 267	 * count registers.
 268	 */
 269	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
 270		[SCSMR]		= { 0x00, 16 },
 271		[SCBRR]		= { 0x04,  8 },
 272		[SCSCR]		= { 0x08, 16 },
 273		[SCxTDR]	= { 0x0c,  8 },
 274		[SCxSR]		= { 0x10, 16 },
 275		[SCxRDR]	= { 0x14,  8 },
 276		[SCFCR]		= { 0x18, 16 },
 277		[SCFDR]		= { 0x1c, 16 },
 278		[SCTFDR]	= sci_reg_invalid,
 279		[SCRFDR]	= sci_reg_invalid,
 280		[SCSPTR]	= { 0x20, 16 },
 281		[SCLSR]		= { 0x24, 16 },
 282		[HSSRR]		= sci_reg_invalid,
 283		[SCPCR]		= sci_reg_invalid,
 284		[SCPDR]		= sci_reg_invalid,
 285		[SCDL]		= sci_reg_invalid,
 286		[SCCKS]		= sci_reg_invalid,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 287	},
 288
 289	/*
 290	 * Common SH-3 SCIF definitions.
 291	 */
 292	[SCIx_SH3_SCIF_REGTYPE] = {
 293		[SCSMR]		= { 0x00,  8 },
 294		[SCBRR]		= { 0x02,  8 },
 295		[SCSCR]		= { 0x04,  8 },
 296		[SCxTDR]	= { 0x06,  8 },
 297		[SCxSR]		= { 0x08, 16 },
 298		[SCxRDR]	= { 0x0a,  8 },
 299		[SCFCR]		= { 0x0c,  8 },
 300		[SCFDR]		= { 0x0e, 16 },
 301		[SCTFDR]	= sci_reg_invalid,
 302		[SCRFDR]	= sci_reg_invalid,
 303		[SCSPTR]	= sci_reg_invalid,
 304		[SCLSR]		= sci_reg_invalid,
 305		[HSSRR]		= sci_reg_invalid,
 306		[SCPCR]		= sci_reg_invalid,
 307		[SCPDR]		= sci_reg_invalid,
 308		[SCDL]		= sci_reg_invalid,
 309		[SCCKS]		= sci_reg_invalid,
 310	},
 311
 312	/*
 313	 * Common SH-4(A) SCIF(B) definitions.
 314	 */
 315	[SCIx_SH4_SCIF_REGTYPE] = {
 316		[SCSMR]		= { 0x00, 16 },
 317		[SCBRR]		= { 0x04,  8 },
 318		[SCSCR]		= { 0x08, 16 },
 319		[SCxTDR]	= { 0x0c,  8 },
 320		[SCxSR]		= { 0x10, 16 },
 321		[SCxRDR]	= { 0x14,  8 },
 322		[SCFCR]		= { 0x18, 16 },
 323		[SCFDR]		= { 0x1c, 16 },
 324		[SCTFDR]	= sci_reg_invalid,
 325		[SCRFDR]	= sci_reg_invalid,
 326		[SCSPTR]	= { 0x20, 16 },
 327		[SCLSR]		= { 0x24, 16 },
 328		[HSSRR]		= sci_reg_invalid,
 329		[SCPCR]		= sci_reg_invalid,
 330		[SCPDR]		= sci_reg_invalid,
 331		[SCDL]		= sci_reg_invalid,
 332		[SCCKS]		= sci_reg_invalid,
 
 333	},
 334
 335	/*
 336	 * Common SCIF definitions for ports with a Baud Rate Generator for
 337	 * External Clock (BRG).
 338	 */
 339	[SCIx_SH4_SCIF_BRG_REGTYPE] = {
 340		[SCSMR]		= { 0x00, 16 },
 341		[SCBRR]		= { 0x04,  8 },
 342		[SCSCR]		= { 0x08, 16 },
 343		[SCxTDR]	= { 0x0c,  8 },
 344		[SCxSR]		= { 0x10, 16 },
 345		[SCxRDR]	= { 0x14,  8 },
 346		[SCFCR]		= { 0x18, 16 },
 347		[SCFDR]		= { 0x1c, 16 },
 348		[SCTFDR]	= sci_reg_invalid,
 349		[SCRFDR]	= sci_reg_invalid,
 350		[SCSPTR]	= { 0x20, 16 },
 351		[SCLSR]		= { 0x24, 16 },
 352		[HSSRR]		= sci_reg_invalid,
 353		[SCPCR]		= sci_reg_invalid,
 354		[SCPDR]		= sci_reg_invalid,
 355		[SCDL]		= { 0x30, 16 },
 356		[SCCKS]		= { 0x34, 16 },
 
 
 
 357	},
 358
 359	/*
 360	 * Common HSCIF definitions.
 361	 */
 362	[SCIx_HSCIF_REGTYPE] = {
 363		[SCSMR]		= { 0x00, 16 },
 364		[SCBRR]		= { 0x04,  8 },
 365		[SCSCR]		= { 0x08, 16 },
 366		[SCxTDR]	= { 0x0c,  8 },
 367		[SCxSR]		= { 0x10, 16 },
 368		[SCxRDR]	= { 0x14,  8 },
 369		[SCFCR]		= { 0x18, 16 },
 370		[SCFDR]		= { 0x1c, 16 },
 371		[SCTFDR]	= sci_reg_invalid,
 372		[SCRFDR]	= sci_reg_invalid,
 373		[SCSPTR]	= { 0x20, 16 },
 374		[SCLSR]		= { 0x24, 16 },
 375		[HSSRR]		= { 0x40, 16 },
 376		[SCPCR]		= sci_reg_invalid,
 377		[SCPDR]		= sci_reg_invalid,
 378		[SCDL]		= { 0x30, 16 },
 379		[SCCKS]		= { 0x34, 16 },
 
 
 
 
 
 
 380	},
 381
 382	/*
 383	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
 384	 * register.
 385	 */
 386	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
 387		[SCSMR]		= { 0x00, 16 },
 388		[SCBRR]		= { 0x04,  8 },
 389		[SCSCR]		= { 0x08, 16 },
 390		[SCxTDR]	= { 0x0c,  8 },
 391		[SCxSR]		= { 0x10, 16 },
 392		[SCxRDR]	= { 0x14,  8 },
 393		[SCFCR]		= { 0x18, 16 },
 394		[SCFDR]		= { 0x1c, 16 },
 395		[SCTFDR]	= sci_reg_invalid,
 396		[SCRFDR]	= sci_reg_invalid,
 397		[SCSPTR]	= sci_reg_invalid,
 398		[SCLSR]		= { 0x24, 16 },
 399		[HSSRR]		= sci_reg_invalid,
 400		[SCPCR]		= sci_reg_invalid,
 401		[SCPDR]		= sci_reg_invalid,
 402		[SCDL]		= sci_reg_invalid,
 403		[SCCKS]		= sci_reg_invalid,
 404	},
 405
 406	/*
 407	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
 408	 * count registers.
 409	 */
 410	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
 411		[SCSMR]		= { 0x00, 16 },
 412		[SCBRR]		= { 0x04,  8 },
 413		[SCSCR]		= { 0x08, 16 },
 414		[SCxTDR]	= { 0x0c,  8 },
 415		[SCxSR]		= { 0x10, 16 },
 416		[SCxRDR]	= { 0x14,  8 },
 417		[SCFCR]		= { 0x18, 16 },
 418		[SCFDR]		= { 0x1c, 16 },
 419		[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
 420		[SCRFDR]	= { 0x20, 16 },
 421		[SCSPTR]	= { 0x24, 16 },
 422		[SCLSR]		= { 0x28, 16 },
 423		[HSSRR]		= sci_reg_invalid,
 424		[SCPCR]		= sci_reg_invalid,
 425		[SCPDR]		= sci_reg_invalid,
 426		[SCDL]		= sci_reg_invalid,
 427		[SCCKS]		= sci_reg_invalid,
 
 
 
 428	},
 429
 430	/*
 431	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
 432	 * registers.
 433	 */
 434	[SCIx_SH7705_SCIF_REGTYPE] = {
 435		[SCSMR]		= { 0x00, 16 },
 436		[SCBRR]		= { 0x04,  8 },
 437		[SCSCR]		= { 0x08, 16 },
 438		[SCxTDR]	= { 0x20,  8 },
 439		[SCxSR]		= { 0x14, 16 },
 440		[SCxRDR]	= { 0x24,  8 },
 441		[SCFCR]		= { 0x18, 16 },
 442		[SCFDR]		= { 0x1c, 16 },
 443		[SCTFDR]	= sci_reg_invalid,
 444		[SCRFDR]	= sci_reg_invalid,
 445		[SCSPTR]	= sci_reg_invalid,
 446		[SCLSR]		= sci_reg_invalid,
 447		[HSSRR]		= sci_reg_invalid,
 448		[SCPCR]		= sci_reg_invalid,
 449		[SCPDR]		= sci_reg_invalid,
 450		[SCDL]		= sci_reg_invalid,
 451		[SCCKS]		= sci_reg_invalid,
 452	},
 453};
 454
 455#define sci_getreg(up, offset)		(sci_regmap[to_sci_port(up)->cfg->regtype] + offset)
 456
 457/*
 458 * The "offset" here is rather misleading, in that it refers to an enum
 459 * value relative to the port mapping rather than the fixed offset
 460 * itself, which needs to be manually retrieved from the platform's
 461 * register map for the given port.
 462 */
 463static unsigned int sci_serial_in(struct uart_port *p, int offset)
 464{
 465	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 466
 467	if (reg->size == 8)
 468		return ioread8(p->membase + (reg->offset << p->regshift));
 469	else if (reg->size == 16)
 470		return ioread16(p->membase + (reg->offset << p->regshift));
 471	else
 472		WARN(1, "Invalid register access\n");
 473
 474	return 0;
 475}
 476
 477static void sci_serial_out(struct uart_port *p, int offset, int value)
 478{
 479	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 480
 481	if (reg->size == 8)
 482		iowrite8(value, p->membase + (reg->offset << p->regshift));
 483	else if (reg->size == 16)
 484		iowrite16(value, p->membase + (reg->offset << p->regshift));
 485	else
 486		WARN(1, "Invalid register access\n");
 487}
 488
 489static int sci_probe_regmap(struct plat_sci_port *cfg)
 490{
 491	switch (cfg->type) {
 492	case PORT_SCI:
 493		cfg->regtype = SCIx_SCI_REGTYPE;
 494		break;
 495	case PORT_IRDA:
 496		cfg->regtype = SCIx_IRDA_REGTYPE;
 497		break;
 498	case PORT_SCIFA:
 499		cfg->regtype = SCIx_SCIFA_REGTYPE;
 500		break;
 501	case PORT_SCIFB:
 502		cfg->regtype = SCIx_SCIFB_REGTYPE;
 503		break;
 504	case PORT_SCIF:
 505		/*
 506		 * The SH-4 is a bit of a misnomer here, although that's
 507		 * where this particular port layout originated. This
 508		 * configuration (or some slight variation thereof)
 509		 * remains the dominant model for all SCIFs.
 510		 */
 511		cfg->regtype = SCIx_SH4_SCIF_REGTYPE;
 512		break;
 513	case PORT_HSCIF:
 514		cfg->regtype = SCIx_HSCIF_REGTYPE;
 515		break;
 516	default:
 517		pr_err("Can't probe register map for given port\n");
 518		return -EINVAL;
 519	}
 520
 521	return 0;
 522}
 523
 524static void sci_port_enable(struct sci_port *sci_port)
 525{
 526	unsigned int i;
 527
 528	if (!sci_port->port.dev)
 529		return;
 530
 531	pm_runtime_get_sync(sci_port->port.dev);
 532
 533	for (i = 0; i < SCI_NUM_CLKS; i++) {
 534		clk_prepare_enable(sci_port->clks[i]);
 535		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
 536	}
 537	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
 538}
 539
 540static void sci_port_disable(struct sci_port *sci_port)
 541{
 542	unsigned int i;
 543
 544	if (!sci_port->port.dev)
 545		return;
 546
 547	/* Cancel the break timer to ensure that the timer handler will not try
 548	 * to access the hardware with clocks and power disabled. Reset the
 549	 * break flag to make the break debouncing state machine ready for the
 550	 * next break.
 551	 */
 552	del_timer_sync(&sci_port->break_timer);
 553	sci_port->break_flag = 0;
 554
 555	for (i = SCI_NUM_CLKS; i-- > 0; )
 556		clk_disable_unprepare(sci_port->clks[i]);
 557
 558	pm_runtime_put_sync(sci_port->port.dev);
 559}
 560
 561static inline unsigned long port_rx_irq_mask(struct uart_port *port)
 562{
 563	/*
 564	 * Not all ports (such as SCIFA) will support REIE. Rather than
 565	 * special-casing the port type, we check the port initialization
 566	 * IRQ enable mask to see whether the IRQ is desired at all. If
 567	 * it's unset, it's logically inferred that there's no point in
 568	 * testing for it.
 569	 */
 570	return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
 571}
 572
 573static void sci_start_tx(struct uart_port *port)
 574{
 575	struct sci_port *s = to_sci_port(port);
 576	unsigned short ctrl;
 577
 578#ifdef CONFIG_SERIAL_SH_SCI_DMA
 579	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 580		u16 new, scr = serial_port_in(port, SCSCR);
 581		if (s->chan_tx)
 582			new = scr | SCSCR_TDRQE;
 583		else
 584			new = scr & ~SCSCR_TDRQE;
 585		if (new != scr)
 586			serial_port_out(port, SCSCR, new);
 587	}
 588
 589	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
 590	    dma_submit_error(s->cookie_tx)) {
 
 
 
 
 591		s->cookie_tx = 0;
 592		schedule_work(&s->work_tx);
 593	}
 594#endif
 595
 596	if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 
 597		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
 598		ctrl = serial_port_in(port, SCSCR);
 
 
 
 
 
 
 
 
 
 599		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
 600	}
 601}
 602
 603static void sci_stop_tx(struct uart_port *port)
 604{
 605	unsigned short ctrl;
 606
 607	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
 608	ctrl = serial_port_in(port, SCSCR);
 609
 610	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 611		ctrl &= ~SCSCR_TDRQE;
 612
 613	ctrl &= ~SCSCR_TIE;
 614
 615	serial_port_out(port, SCSCR, ctrl);
 
 
 
 
 
 
 
 
 616}
 617
 618static void sci_start_rx(struct uart_port *port)
 619{
 620	unsigned short ctrl;
 621
 622	ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
 623
 624	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 625		ctrl &= ~SCSCR_RDRQE;
 626
 627	serial_port_out(port, SCSCR, ctrl);
 628}
 629
 630static void sci_stop_rx(struct uart_port *port)
 631{
 632	unsigned short ctrl;
 633
 634	ctrl = serial_port_in(port, SCSCR);
 635
 636	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 637		ctrl &= ~SCSCR_RDRQE;
 638
 639	ctrl &= ~port_rx_irq_mask(port);
 640
 641	serial_port_out(port, SCSCR, ctrl);
 642}
 643
 644static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
 645{
 646	if (port->type == PORT_SCI) {
 647		/* Just store the mask */
 648		serial_port_out(port, SCxSR, mask);
 649	} else if (to_sci_port(port)->overrun_mask == SCIFA_ORER) {
 650		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
 651		/* Only clear the status bits we want to clear */
 652		serial_port_out(port, SCxSR,
 653				serial_port_in(port, SCxSR) & mask);
 654	} else {
 655		/* Store the mask, clear parity/framing errors */
 656		serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
 657	}
 658}
 659
 660#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
 661    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
 662
 663#ifdef CONFIG_CONSOLE_POLL
 664static int sci_poll_get_char(struct uart_port *port)
 665{
 666	unsigned short status;
 667	int c;
 668
 669	do {
 670		status = serial_port_in(port, SCxSR);
 671		if (status & SCxSR_ERRORS(port)) {
 672			sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
 673			continue;
 674		}
 675		break;
 676	} while (1);
 677
 678	if (!(status & SCxSR_RDxF(port)))
 679		return NO_POLL_CHAR;
 680
 681	c = serial_port_in(port, SCxRDR);
 682
 683	/* Dummy read */
 684	serial_port_in(port, SCxSR);
 685	sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 686
 687	return c;
 688}
 689#endif
 690
 691static void sci_poll_put_char(struct uart_port *port, unsigned char c)
 692{
 693	unsigned short status;
 694
 695	do {
 696		status = serial_port_in(port, SCxSR);
 697	} while (!(status & SCxSR_TDxE(port)));
 698
 699	serial_port_out(port, SCxTDR, c);
 700	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
 701}
 702#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
 703	  CONFIG_SERIAL_SH_SCI_EARLYCON */
 704
 705static void sci_init_pins(struct uart_port *port, unsigned int cflag)
 706{
 707	struct sci_port *s = to_sci_port(port);
 708
 709	/*
 710	 * Use port-specific handler if provided.
 711	 */
 712	if (s->cfg->ops && s->cfg->ops->init_pins) {
 713		s->cfg->ops->init_pins(port, cflag);
 714		return;
 715	}
 716
 717	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 
 718		u16 ctrl = serial_port_in(port, SCPCR);
 719
 720		/* Enable RXD and TXD pin functions */
 721		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
 722		if (to_sci_port(port)->cfg->capabilities & SCIx_HAVE_RTSCTS) {
 723			/* RTS# is output, driven 1 */
 724			ctrl |= SCPCR_RTSC;
 725			serial_port_out(port, SCPDR,
 726				serial_port_in(port, SCPDR) | SCPDR_RTSD);
 
 
 
 
 
 
 
 727			/* Enable CTS# pin function */
 728			ctrl &= ~SCPCR_CTSC;
 729		}
 
 730		serial_port_out(port, SCPCR, ctrl);
 731	} else if (sci_getreg(port, SCSPTR)->size) {
 732		u16 status = serial_port_in(port, SCSPTR);
 733
 734		/* RTS# is output, driven 1 */
 735		status |= SCSPTR_RTSIO | SCSPTR_RTSDT;
 
 
 
 
 736		/* CTS# and SCK are inputs */
 737		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
 738		serial_port_out(port, SCSPTR, status);
 739	}
 740}
 741
 742static int sci_txfill(struct uart_port *port)
 743{
 
 
 744	const struct plat_sci_reg *reg;
 745
 746	reg = sci_getreg(port, SCTFDR);
 747	if (reg->size)
 748		return serial_port_in(port, SCTFDR) & ((port->fifosize << 1) - 1);
 749
 750	reg = sci_getreg(port, SCFDR);
 751	if (reg->size)
 752		return serial_port_in(port, SCFDR) >> 8;
 753
 754	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
 755}
 756
 757static int sci_txroom(struct uart_port *port)
 758{
 759	return port->fifosize - sci_txfill(port);
 760}
 761
 762static int sci_rxfill(struct uart_port *port)
 763{
 
 
 764	const struct plat_sci_reg *reg;
 765
 766	reg = sci_getreg(port, SCRFDR);
 767	if (reg->size)
 768		return serial_port_in(port, SCRFDR) & ((port->fifosize << 1) - 1);
 769
 770	reg = sci_getreg(port, SCFDR);
 771	if (reg->size)
 772		return serial_port_in(port, SCFDR) & ((port->fifosize << 1) - 1);
 773
 774	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
 775}
 776
 777/*
 778 * SCI helper for checking the state of the muxed port/RXD pins.
 779 */
 780static inline int sci_rxd_in(struct uart_port *port)
 781{
 782	struct sci_port *s = to_sci_port(port);
 783
 784	if (s->cfg->port_reg <= 0)
 785		return 1;
 786
 787	/* Cast for ARM damage */
 788	return !!__raw_readb((void __iomem *)(uintptr_t)s->cfg->port_reg);
 789}
 790
 791/* ********************************************************************** *
 792 *                   the interrupt related routines                       *
 793 * ********************************************************************** */
 794
 795static void sci_transmit_chars(struct uart_port *port)
 796{
 797	struct circ_buf *xmit = &port->state->xmit;
 798	unsigned int stopped = uart_tx_stopped(port);
 799	unsigned short status;
 800	unsigned short ctrl;
 801	int count;
 802
 803	status = serial_port_in(port, SCxSR);
 804	if (!(status & SCxSR_TDxE(port))) {
 805		ctrl = serial_port_in(port, SCSCR);
 806		if (uart_circ_empty(xmit))
 807			ctrl &= ~SCSCR_TIE;
 808		else
 809			ctrl |= SCSCR_TIE;
 810		serial_port_out(port, SCSCR, ctrl);
 811		return;
 812	}
 813
 814	count = sci_txroom(port);
 815
 816	do {
 817		unsigned char c;
 818
 819		if (port->x_char) {
 820			c = port->x_char;
 821			port->x_char = 0;
 822		} else if (!uart_circ_empty(xmit) && !stopped) {
 823			c = xmit->buf[xmit->tail];
 824			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 
 
 
 
 
 825		} else {
 826			break;
 827		}
 828
 829		serial_port_out(port, SCxTDR, c);
 830
 831		port->icount.tx++;
 832	} while (--count > 0);
 833
 834	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
 835
 836	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 837		uart_write_wakeup(port);
 838	if (uart_circ_empty(xmit)) {
 839		sci_stop_tx(port);
 840	} else {
 841		ctrl = serial_port_in(port, SCSCR);
 842
 843		if (port->type != PORT_SCI) {
 844			serial_port_in(port, SCxSR); /* Dummy read */
 845			sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
 846		}
 847
 848		ctrl |= SCSCR_TIE;
 849		serial_port_out(port, SCSCR, ctrl);
 850	}
 851}
 852
 853/* On SH3, SCIF may read end-of-break as a space->mark char */
 854#define STEPFN(c)  ({int __c = (c); (((__c-1)|(__c)) == -1); })
 855
 856static void sci_receive_chars(struct uart_port *port)
 857{
 858	struct sci_port *sci_port = to_sci_port(port);
 859	struct tty_port *tport = &port->state->port;
 860	int i, count, copied = 0;
 861	unsigned short status;
 862	unsigned char flag;
 863
 864	status = serial_port_in(port, SCxSR);
 865	if (!(status & SCxSR_RDxF(port)))
 866		return;
 867
 868	while (1) {
 869		/* Don't copy more bytes than there is room for in the buffer */
 870		count = tty_buffer_request_room(tport, sci_rxfill(port));
 871
 872		/* If for any reason we can't copy more data, we're done! */
 873		if (count == 0)
 874			break;
 875
 876		if (port->type == PORT_SCI) {
 877			char c = serial_port_in(port, SCxRDR);
 878			if (uart_handle_sysrq_char(port, c) ||
 879			    sci_port->break_flag)
 880				count = 0;
 881			else
 882				tty_insert_flip_char(tport, c, TTY_NORMAL);
 883		} else {
 884			for (i = 0; i < count; i++) {
 885				char c = serial_port_in(port, SCxRDR);
 886
 887				status = serial_port_in(port, SCxSR);
 888#if defined(CONFIG_CPU_SH3)
 889				/* Skip "chars" during break */
 890				if (sci_port->break_flag) {
 891					if ((c == 0) &&
 892					    (status & SCxSR_FER(port))) {
 893						count--; i--;
 894						continue;
 895					}
 896
 897					/* Nonzero => end-of-break */
 898					dev_dbg(port->dev, "debounce<%02x>\n", c);
 899					sci_port->break_flag = 0;
 900
 901					if (STEPFN(c)) {
 902						count--; i--;
 903						continue;
 904					}
 905				}
 906#endif /* CONFIG_CPU_SH3 */
 907				if (uart_handle_sysrq_char(port, c)) {
 908					count--; i--;
 909					continue;
 910				}
 911
 912				/* Store data and status */
 913				if (status & SCxSR_FER(port)) {
 914					flag = TTY_FRAME;
 915					port->icount.frame++;
 916					dev_notice(port->dev, "frame error\n");
 917				} else if (status & SCxSR_PER(port)) {
 918					flag = TTY_PARITY;
 919					port->icount.parity++;
 920					dev_notice(port->dev, "parity error\n");
 921				} else
 922					flag = TTY_NORMAL;
 923
 924				tty_insert_flip_char(tport, c, flag);
 925			}
 926		}
 927
 928		serial_port_in(port, SCxSR); /* dummy read */
 929		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 930
 931		copied += count;
 932		port->icount.rx += count;
 933	}
 934
 935	if (copied) {
 936		/* Tell the rest of the system the news. New characters! */
 937		tty_flip_buffer_push(tport);
 938	} else {
 
 
 939		serial_port_in(port, SCxSR); /* dummy read */
 940		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 941	}
 942}
 943
 944#define SCI_BREAK_JIFFIES (HZ/20)
 945
 946/*
 947 * The sci generates interrupts during the break,
 948 * 1 per millisecond or so during the break period, for 9600 baud.
 949 * So dont bother disabling interrupts.
 950 * But dont want more than 1 break event.
 951 * Use a kernel timer to periodically poll the rx line until
 952 * the break is finished.
 953 */
 954static inline void sci_schedule_break_timer(struct sci_port *port)
 955{
 956	mod_timer(&port->break_timer, jiffies + SCI_BREAK_JIFFIES);
 957}
 958
 959/* Ensure that two consecutive samples find the break over. */
 960static void sci_break_timer(unsigned long data)
 961{
 962	struct sci_port *port = (struct sci_port *)data;
 963
 964	if (sci_rxd_in(&port->port) == 0) {
 965		port->break_flag = 1;
 966		sci_schedule_break_timer(port);
 967	} else if (port->break_flag == 1) {
 968		/* break is over. */
 969		port->break_flag = 2;
 970		sci_schedule_break_timer(port);
 971	} else
 972		port->break_flag = 0;
 973}
 974
 975static int sci_handle_errors(struct uart_port *port)
 976{
 977	int copied = 0;
 978	unsigned short status = serial_port_in(port, SCxSR);
 979	struct tty_port *tport = &port->state->port;
 980	struct sci_port *s = to_sci_port(port);
 981
 982	/* Handle overruns */
 983	if (status & s->overrun_mask) {
 984		port->icount.overrun++;
 985
 986		/* overrun error */
 987		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
 988			copied++;
 989
 990		dev_notice(port->dev, "overrun error\n");
 991	}
 992
 993	if (status & SCxSR_FER(port)) {
 994		if (sci_rxd_in(port) == 0) {
 995			/* Notify of BREAK */
 996			struct sci_port *sci_port = to_sci_port(port);
 997
 998			if (!sci_port->break_flag) {
 999				port->icount.brk++;
1000
1001				sci_port->break_flag = 1;
1002				sci_schedule_break_timer(sci_port);
1003
1004				/* Do sysrq handling. */
1005				if (uart_handle_break(port))
1006					return 0;
1007
1008				dev_dbg(port->dev, "BREAK detected\n");
1009
1010				if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1011					copied++;
1012			}
1013
1014		} else {
1015			/* frame error */
1016			port->icount.frame++;
1017
1018			if (tty_insert_flip_char(tport, 0, TTY_FRAME))
1019				copied++;
1020
1021			dev_notice(port->dev, "frame error\n");
1022		}
1023	}
1024
1025	if (status & SCxSR_PER(port)) {
1026		/* parity error */
1027		port->icount.parity++;
1028
1029		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
1030			copied++;
1031
1032		dev_notice(port->dev, "parity error\n");
1033	}
1034
1035	if (copied)
1036		tty_flip_buffer_push(tport);
1037
1038	return copied;
1039}
1040
1041static int sci_handle_fifo_overrun(struct uart_port *port)
1042{
1043	struct tty_port *tport = &port->state->port;
1044	struct sci_port *s = to_sci_port(port);
1045	const struct plat_sci_reg *reg;
1046	int copied = 0;
1047	u16 status;
1048
1049	reg = sci_getreg(port, s->overrun_reg);
1050	if (!reg->size)
1051		return 0;
1052
1053	status = serial_port_in(port, s->overrun_reg);
1054	if (status & s->overrun_mask) {
1055		status &= ~s->overrun_mask;
1056		serial_port_out(port, s->overrun_reg, status);
1057
1058		port->icount.overrun++;
1059
1060		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
1061		tty_flip_buffer_push(tport);
1062
1063		dev_dbg(port->dev, "overrun error\n");
1064		copied++;
1065	}
1066
1067	return copied;
1068}
1069
1070static int sci_handle_breaks(struct uart_port *port)
1071{
1072	int copied = 0;
1073	unsigned short status = serial_port_in(port, SCxSR);
1074	struct tty_port *tport = &port->state->port;
1075	struct sci_port *s = to_sci_port(port);
1076
1077	if (uart_handle_break(port))
1078		return 0;
1079
1080	if (!s->break_flag && status & SCxSR_BRK(port)) {
1081#if defined(CONFIG_CPU_SH3)
1082		/* Debounce break */
1083		s->break_flag = 1;
1084#endif
1085
1086		port->icount.brk++;
1087
1088		/* Notify of BREAK */
1089		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1090			copied++;
1091
1092		dev_dbg(port->dev, "BREAK detected\n");
1093	}
1094
1095	if (copied)
1096		tty_flip_buffer_push(tport);
1097
1098	copied += sci_handle_fifo_overrun(port);
1099
1100	return copied;
1101}
1102
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1103#ifdef CONFIG_SERIAL_SH_SCI_DMA
1104static void sci_dma_tx_complete(void *arg)
1105{
1106	struct sci_port *s = arg;
1107	struct uart_port *port = &s->port;
1108	struct circ_buf *xmit = &port->state->xmit;
1109	unsigned long flags;
1110
1111	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1112
1113	spin_lock_irqsave(&port->lock, flags);
1114
1115	xmit->tail += s->tx_dma_len;
1116	xmit->tail &= UART_XMIT_SIZE - 1;
1117
1118	port->icount.tx += s->tx_dma_len;
1119
1120	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1121		uart_write_wakeup(port);
1122
1123	if (!uart_circ_empty(xmit)) {
1124		s->cookie_tx = 0;
1125		schedule_work(&s->work_tx);
1126	} else {
1127		s->cookie_tx = -EINVAL;
1128		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 
1129			u16 ctrl = serial_port_in(port, SCSCR);
1130			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
 
 
 
 
 
1131		}
1132	}
1133
1134	spin_unlock_irqrestore(&port->lock, flags);
1135}
1136
1137/* Locking: called with port lock held */
1138static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1139{
1140	struct uart_port *port = &s->port;
1141	struct tty_port *tport = &port->state->port;
1142	int copied;
1143
1144	copied = tty_insert_flip_string(tport, buf, count);
1145	if (copied < count)
1146		port->icount.buf_overrun++;
1147
1148	port->icount.rx += copied;
1149
1150	return copied;
1151}
1152
1153static int sci_dma_rx_find_active(struct sci_port *s)
1154{
1155	unsigned int i;
1156
1157	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1158		if (s->active_rx == s->cookie_rx[i])
1159			return i;
1160
1161	return -1;
1162}
1163
1164static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
1165{
1166	struct dma_chan *chan = s->chan_rx;
1167	struct uart_port *port = &s->port;
1168	unsigned long flags;
1169
1170	spin_lock_irqsave(&port->lock, flags);
1171	s->chan_rx = NULL;
1172	s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1173	spin_unlock_irqrestore(&port->lock, flags);
1174	dmaengine_terminate_all(chan);
 
 
 
 
 
 
 
 
 
1175	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1176			  sg_dma_address(&s->sg_rx[0]));
1177	dma_release_channel(chan);
1178	if (enable_pio)
1179		sci_start_rx(port);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1180}
1181
1182static void sci_dma_rx_complete(void *arg)
1183{
1184	struct sci_port *s = arg;
1185	struct dma_chan *chan = s->chan_rx;
1186	struct uart_port *port = &s->port;
1187	struct dma_async_tx_descriptor *desc;
1188	unsigned long flags;
1189	int active, count = 0;
1190
1191	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1192		s->active_rx);
1193
1194	spin_lock_irqsave(&port->lock, flags);
1195
1196	active = sci_dma_rx_find_active(s);
1197	if (active >= 0)
1198		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1199
1200	mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
1201
1202	if (count)
1203		tty_flip_buffer_push(&port->state->port);
1204
1205	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1206				       DMA_DEV_TO_MEM,
1207				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1208	if (!desc)
1209		goto fail;
1210
1211	desc->callback = sci_dma_rx_complete;
1212	desc->callback_param = s;
1213	s->cookie_rx[active] = dmaengine_submit(desc);
1214	if (dma_submit_error(s->cookie_rx[active]))
1215		goto fail;
1216
1217	s->active_rx = s->cookie_rx[!active];
1218
1219	dma_async_issue_pending(chan);
1220
1221	spin_unlock_irqrestore(&port->lock, flags);
1222	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1223		__func__, s->cookie_rx[active], active, s->active_rx);
1224	return;
1225
1226fail:
1227	spin_unlock_irqrestore(&port->lock, flags);
1228	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1229	sci_rx_dma_release(s, true);
 
 
 
 
 
1230}
1231
1232static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
1233{
1234	struct dma_chan *chan = s->chan_tx;
1235	struct uart_port *port = &s->port;
1236	unsigned long flags;
1237
1238	spin_lock_irqsave(&port->lock, flags);
1239	s->chan_tx = NULL;
1240	s->cookie_tx = -EINVAL;
1241	spin_unlock_irqrestore(&port->lock, flags);
1242	dmaengine_terminate_all(chan);
1243	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1244			 DMA_TO_DEVICE);
1245	dma_release_channel(chan);
1246	if (enable_pio)
1247		sci_start_tx(port);
1248}
1249
1250static void sci_submit_rx(struct sci_port *s)
1251{
1252	struct dma_chan *chan = s->chan_rx;
 
 
1253	int i;
1254
1255	for (i = 0; i < 2; i++) {
1256		struct scatterlist *sg = &s->sg_rx[i];
1257		struct dma_async_tx_descriptor *desc;
1258
1259		desc = dmaengine_prep_slave_sg(chan,
1260			sg, 1, DMA_DEV_TO_MEM,
1261			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1262		if (!desc)
1263			goto fail;
1264
1265		desc->callback = sci_dma_rx_complete;
1266		desc->callback_param = s;
1267		s->cookie_rx[i] = dmaengine_submit(desc);
1268		if (dma_submit_error(s->cookie_rx[i]))
1269			goto fail;
1270
1271	}
1272
1273	s->active_rx = s->cookie_rx[0];
1274
1275	dma_async_issue_pending(chan);
1276	return;
1277
1278fail:
 
 
 
1279	if (i)
1280		dmaengine_terminate_all(chan);
1281	for (i = 0; i < 2; i++)
1282		s->cookie_rx[i] = -EINVAL;
1283	s->active_rx = -EINVAL;
1284	sci_rx_dma_release(s, true);
 
1285}
1286
1287static void work_fn_tx(struct work_struct *work)
1288{
1289	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1290	struct dma_async_tx_descriptor *desc;
1291	struct dma_chan *chan = s->chan_tx;
1292	struct uart_port *port = &s->port;
1293	struct circ_buf *xmit = &port->state->xmit;
 
1294	dma_addr_t buf;
 
1295
1296	/*
1297	 * DMA is idle now.
1298	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1299	 * offsets and lengths. Since it is a circular buffer, we have to
1300	 * transmit till the end, and then the rest. Take the port lock to get a
1301	 * consistent xmit buffer state.
1302	 */
1303	spin_lock_irq(&port->lock);
1304	buf = s->tx_dma_addr + (xmit->tail & (UART_XMIT_SIZE - 1));
1305	s->tx_dma_len = min_t(unsigned int,
1306		CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1307		CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1308	spin_unlock_irq(&port->lock);
 
 
 
 
1309
1310	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1311					   DMA_MEM_TO_DEV,
1312					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1313	if (!desc) {
 
1314		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1315		/* switch to PIO */
1316		sci_tx_dma_release(s, true);
1317		return;
1318	}
1319
1320	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1321				   DMA_TO_DEVICE);
1322
1323	spin_lock_irq(&port->lock);
1324	desc->callback = sci_dma_tx_complete;
1325	desc->callback_param = s;
1326	spin_unlock_irq(&port->lock);
1327	s->cookie_tx = dmaengine_submit(desc);
1328	if (dma_submit_error(s->cookie_tx)) {
 
1329		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1330		/* switch to PIO */
1331		sci_tx_dma_release(s, true);
1332		return;
1333	}
1334
 
1335	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1336		__func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1337
1338	dma_async_issue_pending(chan);
 
 
 
 
 
 
 
 
1339}
1340
1341static void rx_timer_fn(unsigned long arg)
1342{
1343	struct sci_port *s = (struct sci_port *)arg;
1344	struct dma_chan *chan = s->chan_rx;
1345	struct uart_port *port = &s->port;
1346	struct dma_tx_state state;
1347	enum dma_status status;
1348	unsigned long flags;
1349	unsigned int read;
1350	int active, count;
1351	u16 scr;
1352
1353	dev_dbg(port->dev, "DMA Rx timed out\n");
1354
1355	spin_lock_irqsave(&port->lock, flags);
1356
1357	active = sci_dma_rx_find_active(s);
1358	if (active < 0) {
1359		spin_unlock_irqrestore(&port->lock, flags);
1360		return;
1361	}
1362
1363	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1364	if (status == DMA_COMPLETE) {
1365		spin_unlock_irqrestore(&port->lock, flags);
1366		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1367			s->active_rx, active);
1368
1369		/* Let packet complete handler take care of the packet */
1370		return;
1371	}
1372
1373	dmaengine_pause(chan);
1374
1375	/*
1376	 * sometimes DMA transfer doesn't stop even if it is stopped and
1377	 * data keeps on coming until transaction is complete so check
1378	 * for DMA_COMPLETE again
1379	 * Let packet complete handler take care of the packet
1380	 */
1381	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1382	if (status == DMA_COMPLETE) {
1383		spin_unlock_irqrestore(&port->lock, flags);
1384		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1385		return;
1386	}
1387
1388	/* Handle incomplete DMA receive */
1389	dmaengine_terminate_all(s->chan_rx);
1390	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1391
1392	if (read) {
1393		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1394		if (count)
1395			tty_flip_buffer_push(&port->state->port);
1396	}
1397
1398	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1399		sci_submit_rx(s);
 
 
 
1400
1401	/* Direct new serial port interrupts back to CPU */
1402	scr = serial_port_in(port, SCSCR);
1403	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1404		scr &= ~SCSCR_RDRQE;
1405		enable_irq(s->irqs[SCIx_RXI_IRQ]);
1406	}
1407	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1408
1409	spin_unlock_irqrestore(&port->lock, flags);
1410}
1411
1412static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1413					     enum dma_transfer_direction dir,
1414					     unsigned int id)
1415{
1416	dma_cap_mask_t mask;
1417	struct dma_chan *chan;
1418	struct dma_slave_config cfg;
1419	int ret;
1420
1421	dma_cap_zero(mask);
1422	dma_cap_set(DMA_SLAVE, mask);
1423
1424	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1425					(void *)(unsigned long)id, port->dev,
1426					dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1427	if (!chan) {
1428		dev_warn(port->dev,
1429			 "dma_request_slave_channel_compat failed\n");
1430		return NULL;
1431	}
1432
1433	memset(&cfg, 0, sizeof(cfg));
1434	cfg.direction = dir;
1435	if (dir == DMA_MEM_TO_DEV) {
1436		cfg.dst_addr = port->mapbase +
1437			(sci_getreg(port, SCxTDR)->offset << port->regshift);
1438		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1439	} else {
1440		cfg.src_addr = port->mapbase +
1441			(sci_getreg(port, SCxRDR)->offset << port->regshift);
1442		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1443	}
1444
1445	ret = dmaengine_slave_config(chan, &cfg);
1446	if (ret) {
1447		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1448		dma_release_channel(chan);
1449		return NULL;
1450	}
1451
1452	return chan;
1453}
1454
1455static void sci_request_dma(struct uart_port *port)
1456{
1457	struct sci_port *s = to_sci_port(port);
1458	struct dma_chan *chan;
1459
1460	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1461
1462	if (!port->dev->of_node &&
1463	    (s->cfg->dma_slave_tx <= 0 || s->cfg->dma_slave_rx <= 0))
 
 
 
 
 
 
1464		return;
1465
1466	s->cookie_tx = -EINVAL;
1467	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV, s->cfg->dma_slave_tx);
 
 
 
 
 
 
 
 
1468	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1469	if (chan) {
1470		s->chan_tx = chan;
1471		/* UART circular tx buffer is an aligned page. */
1472		s->tx_dma_addr = dma_map_single(chan->device->dev,
1473						port->state->xmit.buf,
1474						UART_XMIT_SIZE,
1475						DMA_TO_DEVICE);
1476		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1477			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1478			dma_release_channel(chan);
1479			s->chan_tx = NULL;
1480		} else {
1481			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1482				__func__, UART_XMIT_SIZE,
1483				port->state->xmit.buf, &s->tx_dma_addr);
 
 
 
1484		}
1485
1486		INIT_WORK(&s->work_tx, work_fn_tx);
1487	}
1488
1489	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM, s->cfg->dma_slave_rx);
1490	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1491	if (chan) {
1492		unsigned int i;
1493		dma_addr_t dma;
1494		void *buf;
1495
1496		s->chan_rx = chan;
1497
1498		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1499		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1500					 &dma, GFP_KERNEL);
1501		if (!buf) {
1502			dev_warn(port->dev,
1503				 "Failed to allocate Rx dma buffer, using PIO\n");
1504			dma_release_channel(chan);
1505			s->chan_rx = NULL;
1506			return;
1507		}
1508
1509		for (i = 0; i < 2; i++) {
1510			struct scatterlist *sg = &s->sg_rx[i];
1511
1512			sg_init_table(sg, 1);
1513			s->rx_buf[i] = buf;
1514			sg_dma_address(sg) = dma;
1515			sg_dma_len(sg) = s->buf_len_rx;
1516
1517			buf += s->buf_len_rx;
1518			dma += s->buf_len_rx;
1519		}
1520
1521		setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s);
 
 
 
1522
1523		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1524			sci_submit_rx(s);
 
1525	}
1526}
1527
1528static void sci_free_dma(struct uart_port *port)
1529{
1530	struct sci_port *s = to_sci_port(port);
1531
1532	if (s->chan_tx)
1533		sci_tx_dma_release(s, false);
1534	if (s->chan_rx)
1535		sci_rx_dma_release(s, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1536}
1537#else
1538static inline void sci_request_dma(struct uart_port *port)
1539{
1540}
1541
1542static inline void sci_free_dma(struct uart_port *port)
1543{
1544}
1545#endif
 
 
1546
1547static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1548{
1549#ifdef CONFIG_SERIAL_SH_SCI_DMA
1550	struct uart_port *port = ptr;
1551	struct sci_port *s = to_sci_port(port);
1552
 
1553	if (s->chan_rx) {
1554		u16 scr = serial_port_in(port, SCSCR);
1555		u16 ssr = serial_port_in(port, SCxSR);
1556
1557		/* Disable future Rx interrupts */
1558		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1559			disable_irq_nosync(irq);
1560			scr |= SCSCR_RDRQE;
 
 
 
 
 
 
1561		} else {
 
 
 
1562			scr &= ~SCSCR_RIE;
1563			sci_submit_rx(s);
1564		}
1565		serial_port_out(port, SCSCR, scr);
1566		/* Clear current interrupt */
1567		serial_port_out(port, SCxSR,
1568				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1569		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n",
1570			jiffies, s->rx_timeout);
1571		mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
1572
1573		return IRQ_HANDLED;
1574	}
 
 
1575#endif
1576
 
 
 
 
 
 
 
 
1577	/* I think sci_receive_chars has to be called irrespective
1578	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1579	 * to be disabled?
1580	 */
1581	sci_receive_chars(ptr);
1582
1583	return IRQ_HANDLED;
1584}
1585
1586static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1587{
1588	struct uart_port *port = ptr;
1589	unsigned long flags;
1590
1591	spin_lock_irqsave(&port->lock, flags);
1592	sci_transmit_chars(port);
1593	spin_unlock_irqrestore(&port->lock, flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1594
1595	return IRQ_HANDLED;
1596}
1597
1598static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1599{
1600	struct uart_port *port = ptr;
1601	struct sci_port *s = to_sci_port(port);
1602
 
 
 
 
 
 
 
 
 
 
 
 
 
1603	/* Handle errors */
1604	if (port->type == PORT_SCI) {
1605		if (sci_handle_errors(port)) {
1606			/* discard character in rx buffer */
1607			serial_port_in(port, SCxSR);
1608			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1609		}
1610	} else {
1611		sci_handle_fifo_overrun(port);
1612		if (!s->chan_rx)
1613			sci_receive_chars(ptr);
1614	}
1615
1616	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1617
1618	/* Kick the transmission */
1619	if (!s->chan_tx)
1620		sci_tx_interrupt(irq, ptr);
1621
1622	return IRQ_HANDLED;
1623}
1624
1625static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1626{
1627	struct uart_port *port = ptr;
1628
1629	/* Handle BREAKs */
1630	sci_handle_breaks(port);
1631	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1632
1633	return IRQ_HANDLED;
1634}
1635
1636static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1637{
1638	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1639	struct uart_port *port = ptr;
1640	struct sci_port *s = to_sci_port(port);
1641	irqreturn_t ret = IRQ_NONE;
1642
1643	ssr_status = serial_port_in(port, SCxSR);
1644	scr_status = serial_port_in(port, SCSCR);
1645	if (s->overrun_reg == SCxSR)
1646		orer_status = ssr_status;
1647	else {
1648		if (sci_getreg(port, s->overrun_reg)->size)
1649			orer_status = serial_port_in(port, s->overrun_reg);
1650	}
1651
1652	err_enabled = scr_status & port_rx_irq_mask(port);
1653
1654	/* Tx Interrupt */
1655	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1656	    !s->chan_tx)
1657		ret = sci_tx_interrupt(irq, ptr);
1658
1659	/*
1660	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1661	 * DR flags
1662	 */
1663	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1664	    (scr_status & SCSCR_RIE))
1665		ret = sci_rx_interrupt(irq, ptr);
1666
1667	/* Error Interrupt */
1668	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1669		ret = sci_er_interrupt(irq, ptr);
1670
1671	/* Break Interrupt */
1672	if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
 
1673		ret = sci_br_interrupt(irq, ptr);
1674
1675	/* Overrun Interrupt */
1676	if (orer_status & s->overrun_mask) {
1677		sci_handle_fifo_overrun(port);
1678		ret = IRQ_HANDLED;
1679	}
1680
1681	return ret;
1682}
1683
1684static const struct sci_irq_desc {
1685	const char	*desc;
1686	irq_handler_t	handler;
1687} sci_irq_desc[] = {
1688	/*
1689	 * Split out handlers, the default case.
1690	 */
1691	[SCIx_ERI_IRQ] = {
1692		.desc = "rx err",
1693		.handler = sci_er_interrupt,
1694	},
1695
1696	[SCIx_RXI_IRQ] = {
1697		.desc = "rx full",
1698		.handler = sci_rx_interrupt,
1699	},
1700
1701	[SCIx_TXI_IRQ] = {
1702		.desc = "tx empty",
1703		.handler = sci_tx_interrupt,
1704	},
1705
1706	[SCIx_BRI_IRQ] = {
1707		.desc = "break",
1708		.handler = sci_br_interrupt,
1709	},
1710
 
 
 
 
 
 
 
 
 
 
1711	/*
1712	 * Special muxed handler.
1713	 */
1714	[SCIx_MUX_IRQ] = {
1715		.desc = "mux",
1716		.handler = sci_mpxed_interrupt,
1717	},
1718};
1719
1720static int sci_request_irq(struct sci_port *port)
1721{
1722	struct uart_port *up = &port->port;
1723	int i, j, ret = 0;
1724
1725	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1726		const struct sci_irq_desc *desc;
1727		int irq;
1728
 
 
 
 
 
 
 
1729		if (SCIx_IRQ_IS_MUXED(port)) {
1730			i = SCIx_MUX_IRQ;
1731			irq = up->irq;
1732		} else {
1733			irq = port->irqs[i];
1734
1735			/*
1736			 * Certain port types won't support all of the
1737			 * available interrupt sources.
1738			 */
1739			if (unlikely(irq < 0))
1740				continue;
1741		}
1742
1743		desc = sci_irq_desc + i;
1744		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1745					    dev_name(up->dev), desc->desc);
1746		if (!port->irqstr[j])
 
1747			goto out_nomem;
 
1748
1749		ret = request_irq(irq, desc->handler, up->irqflags,
1750				  port->irqstr[j], port);
1751		if (unlikely(ret)) {
1752			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1753			goto out_noirq;
1754		}
1755	}
1756
1757	return 0;
1758
1759out_noirq:
1760	while (--i >= 0)
1761		free_irq(port->irqs[i], port);
1762
1763out_nomem:
1764	while (--j >= 0)
1765		kfree(port->irqstr[j]);
1766
1767	return ret;
1768}
1769
1770static void sci_free_irq(struct sci_port *port)
1771{
1772	int i;
1773
1774	/*
1775	 * Intentionally in reverse order so we iterate over the muxed
1776	 * IRQ first.
1777	 */
1778	for (i = 0; i < SCIx_NR_IRQS; i++) {
1779		int irq = port->irqs[i];
1780
1781		/*
1782		 * Certain port types won't support all of the available
1783		 * interrupt sources.
1784		 */
1785		if (unlikely(irq < 0))
1786			continue;
1787
 
 
 
 
 
 
 
1788		free_irq(port->irqs[i], port);
1789		kfree(port->irqstr[i]);
1790
1791		if (SCIx_IRQ_IS_MUXED(port)) {
1792			/* If there's only one IRQ, we're done. */
1793			return;
1794		}
1795	}
1796}
1797
1798static unsigned int sci_tx_empty(struct uart_port *port)
1799{
1800	unsigned short status = serial_port_in(port, SCxSR);
1801	unsigned short in_tx_fifo = sci_txfill(port);
1802
1803	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1804}
1805
1806static void sci_set_rts(struct uart_port *port, bool state)
1807{
1808	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1809		u16 data = serial_port_in(port, SCPDR);
1810
1811		/* Active low */
1812		if (state)
1813			data &= ~SCPDR_RTSD;
1814		else
1815			data |= SCPDR_RTSD;
1816		serial_port_out(port, SCPDR, data);
1817
1818		/* RTS# is output */
1819		serial_port_out(port, SCPCR,
1820				serial_port_in(port, SCPCR) | SCPCR_RTSC);
1821	} else if (sci_getreg(port, SCSPTR)->size) {
1822		u16 ctrl = serial_port_in(port, SCSPTR);
1823
1824		/* Active low */
1825		if (state)
1826			ctrl &= ~SCSPTR_RTSDT;
1827		else
1828			ctrl |= SCSPTR_RTSDT;
1829		serial_port_out(port, SCSPTR, ctrl);
1830	}
1831}
1832
1833static bool sci_get_cts(struct uart_port *port)
1834{
1835	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1836		/* Active low */
1837		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
1838	} else if (sci_getreg(port, SCSPTR)->size) {
1839		/* Active low */
1840		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
1841	}
1842
1843	return true;
1844}
1845
1846/*
1847 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
1848 * CTS/RTS is supported in hardware by at least one port and controlled
1849 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
1850 * handled via the ->init_pins() op, which is a bit of a one-way street,
1851 * lacking any ability to defer pin control -- this will later be
1852 * converted over to the GPIO framework).
1853 *
1854 * Other modes (such as loopback) are supported generically on certain
1855 * port types, but not others. For these it's sufficient to test for the
1856 * existence of the support register and simply ignore the port type.
1857 */
1858static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
1859{
1860	struct sci_port *s = to_sci_port(port);
1861
1862	if (mctrl & TIOCM_LOOP) {
1863		const struct plat_sci_reg *reg;
1864
1865		/*
1866		 * Standard loopback mode for SCFCR ports.
1867		 */
1868		reg = sci_getreg(port, SCFCR);
1869		if (reg->size)
1870			serial_port_out(port, SCFCR,
1871					serial_port_in(port, SCFCR) |
1872					SCFCR_LOOP);
1873	}
1874
1875	mctrl_gpio_set(s->gpios, mctrl);
1876
1877	if (!(s->cfg->capabilities & SCIx_HAVE_RTSCTS))
1878		return;
1879
1880	if (!(mctrl & TIOCM_RTS)) {
1881		/* Disable Auto RTS */
1882		serial_port_out(port, SCFCR,
1883				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
1884
1885		/* Clear RTS */
1886		sci_set_rts(port, 0);
1887	} else if (s->autorts) {
1888		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1889			/* Enable RTS# pin function */
1890			serial_port_out(port, SCPCR,
1891				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
1892		}
1893
1894		/* Enable Auto RTS */
1895		serial_port_out(port, SCFCR,
1896				serial_port_in(port, SCFCR) | SCFCR_MCE);
1897	} else {
1898		/* Set RTS */
1899		sci_set_rts(port, 1);
1900	}
1901}
1902
1903static unsigned int sci_get_mctrl(struct uart_port *port)
1904{
1905	struct sci_port *s = to_sci_port(port);
1906	struct mctrl_gpios *gpios = s->gpios;
1907	unsigned int mctrl = 0;
1908
1909	mctrl_gpio_get(gpios, &mctrl);
1910
1911	/*
1912	 * CTS/RTS is handled in hardware when supported, while nothing
1913	 * else is wired up.
1914	 */
1915	if (s->autorts) {
1916		if (sci_get_cts(port))
1917			mctrl |= TIOCM_CTS;
1918	} else if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS))) {
1919		mctrl |= TIOCM_CTS;
1920	}
1921	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR)))
1922		mctrl |= TIOCM_DSR;
1923	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD)))
1924		mctrl |= TIOCM_CAR;
1925
1926	return mctrl;
1927}
1928
1929static void sci_enable_ms(struct uart_port *port)
1930{
1931	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
1932}
1933
1934static void sci_break_ctl(struct uart_port *port, int break_state)
1935{
1936	unsigned short scscr, scsptr;
 
1937
1938	/* check wheter the port has SCSPTR */
1939	if (!sci_getreg(port, SCSPTR)->size) {
1940		/*
1941		 * Not supported by hardware. Most parts couple break and rx
1942		 * interrupts together, with break detection always enabled.
1943		 */
1944		return;
1945	}
1946
 
1947	scsptr = serial_port_in(port, SCSPTR);
1948	scscr = serial_port_in(port, SCSCR);
1949
1950	if (break_state == -1) {
1951		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
1952		scscr &= ~SCSCR_TE;
1953	} else {
1954		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
1955		scscr |= SCSCR_TE;
1956	}
1957
1958	serial_port_out(port, SCSPTR, scsptr);
1959	serial_port_out(port, SCSCR, scscr);
 
1960}
1961
1962static int sci_startup(struct uart_port *port)
1963{
1964	struct sci_port *s = to_sci_port(port);
1965	int ret;
1966
1967	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1968
 
 
1969	ret = sci_request_irq(s);
1970	if (unlikely(ret < 0))
 
1971		return ret;
1972
1973	sci_request_dma(port);
1974
1975	return 0;
1976}
1977
1978static void sci_shutdown(struct uart_port *port)
1979{
1980	struct sci_port *s = to_sci_port(port);
1981	unsigned long flags;
1982	u16 scr;
1983
1984	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1985
1986	s->autorts = false;
1987	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
1988
1989	spin_lock_irqsave(&port->lock, flags);
1990	sci_stop_rx(port);
1991	sci_stop_tx(port);
1992	/* Stop RX and TX, disable related interrupts, keep clock source */
 
 
 
1993	scr = serial_port_in(port, SCSCR);
1994	serial_port_out(port, SCSCR, scr & (SCSCR_CKE1 | SCSCR_CKE0));
1995	spin_unlock_irqrestore(&port->lock, flags);
 
1996
1997#ifdef CONFIG_SERIAL_SH_SCI_DMA
1998	if (s->chan_rx) {
1999		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2000			port->line);
2001		del_timer_sync(&s->rx_timer);
2002	}
2003#endif
2004
 
 
 
2005	sci_free_dma(port);
2006	sci_free_irq(s);
2007}
2008
2009static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2010			unsigned int *srr)
2011{
2012	unsigned long freq = s->clk_rates[SCI_SCK];
2013	int err, min_err = INT_MAX;
2014	unsigned int sr;
2015
2016	if (s->port.type != PORT_HSCIF)
2017		freq *= 2;
2018
2019	for_each_sr(sr, s) {
2020		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2021		if (abs(err) >= abs(min_err))
2022			continue;
2023
2024		min_err = err;
2025		*srr = sr - 1;
2026
2027		if (!err)
2028			break;
2029	}
2030
2031	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2032		*srr + 1);
2033	return min_err;
2034}
2035
2036static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2037			unsigned long freq, unsigned int *dlr,
2038			unsigned int *srr)
2039{
2040	int err, min_err = INT_MAX;
2041	unsigned int sr, dl;
2042
2043	if (s->port.type != PORT_HSCIF)
2044		freq *= 2;
2045
2046	for_each_sr(sr, s) {
2047		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2048		dl = clamp(dl, 1U, 65535U);
2049
2050		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2051		if (abs(err) >= abs(min_err))
2052			continue;
2053
2054		min_err = err;
2055		*dlr = dl;
2056		*srr = sr - 1;
2057
2058		if (!err)
2059			break;
2060	}
2061
2062	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2063		min_err, *dlr, *srr + 1);
2064	return min_err;
2065}
2066
2067/* calculate sample rate, BRR, and clock select */
2068static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2069			  unsigned int *brr, unsigned int *srr,
2070			  unsigned int *cks)
2071{
2072	unsigned long freq = s->clk_rates[SCI_FCK];
2073	unsigned int sr, br, prediv, scrate, c;
2074	int err, min_err = INT_MAX;
2075
2076	if (s->port.type != PORT_HSCIF)
2077		freq *= 2;
2078
2079	/*
2080	 * Find the combination of sample rate and clock select with the
2081	 * smallest deviation from the desired baud rate.
2082	 * Prefer high sample rates to maximise the receive margin.
2083	 *
2084	 * M: Receive margin (%)
2085	 * N: Ratio of bit rate to clock (N = sampling rate)
2086	 * D: Clock duty (D = 0 to 1.0)
2087	 * L: Frame length (L = 9 to 12)
2088	 * F: Absolute value of clock frequency deviation
2089	 *
2090	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2091	 *      (|D - 0.5| / N * (1 + F))|
2092	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2093	 */
2094	for_each_sr(sr, s) {
2095		for (c = 0; c <= 3; c++) {
2096			/* integerized formulas from HSCIF documentation */
2097			prediv = sr * (1 << (2 * c + 1));
2098
2099			/*
2100			 * We need to calculate:
2101			 *
2102			 *     br = freq / (prediv * bps) clamped to [1..256]
2103			 *     err = freq / (br * prediv) - bps
2104			 *
2105			 * Watch out for overflow when calculating the desired
2106			 * sampling clock rate!
2107			 */
2108			if (bps > UINT_MAX / prediv)
2109				break;
2110
2111			scrate = prediv * bps;
2112			br = DIV_ROUND_CLOSEST(freq, scrate);
2113			br = clamp(br, 1U, 256U);
2114
2115			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2116			if (abs(err) >= abs(min_err))
2117				continue;
2118
2119			min_err = err;
2120			*brr = br - 1;
2121			*srr = sr - 1;
2122			*cks = c;
2123
2124			if (!err)
2125				goto found;
2126		}
2127	}
2128
2129found:
2130	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2131		min_err, *brr, *srr + 1, *cks);
2132	return min_err;
2133}
2134
2135static void sci_reset(struct uart_port *port)
2136{
2137	const struct plat_sci_reg *reg;
2138	unsigned int status;
 
2139
2140	do {
2141		status = serial_port_in(port, SCxSR);
2142	} while (!(status & SCxSR_TEND(port)));
2143
2144	serial_port_out(port, SCSCR, 0x00);	/* TE=0, RE=0, CKE1=0 */
2145
2146	reg = sci_getreg(port, SCFCR);
2147	if (reg->size)
2148		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2149
2150	sci_clear_SCxSR(port,
2151			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2152			SCxSR_BREAK_CLEAR(port));
2153	if (sci_getreg(port, SCLSR)->size) {
2154		status = serial_port_in(port, SCLSR);
2155		status &= ~(SCLSR_TO | SCLSR_ORER);
2156		serial_port_out(port, SCLSR, status);
2157	}
 
 
 
 
 
 
 
 
 
 
 
 
 
2158}
2159
2160static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2161			    struct ktermios *old)
2162{
2163	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i;
2164	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2165	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2166	struct sci_port *s = to_sci_port(port);
2167	const struct plat_sci_reg *reg;
2168	int min_err = INT_MAX, err;
2169	unsigned long max_freq = 0;
2170	int best_clk = -1;
 
2171
2172	if ((termios->c_cflag & CSIZE) == CS7)
2173		smr_val |= SCSMR_CHR;
 
 
 
 
2174	if (termios->c_cflag & PARENB)
2175		smr_val |= SCSMR_PE;
2176	if (termios->c_cflag & PARODD)
2177		smr_val |= SCSMR_PE | SCSMR_ODD;
2178	if (termios->c_cflag & CSTOPB)
2179		smr_val |= SCSMR_STOP;
2180
2181	/*
2182	 * earlyprintk comes here early on with port->uartclk set to zero.
2183	 * the clock framework is not up and running at this point so here
2184	 * we assume that 115200 is the maximum baud rate. please note that
2185	 * the baud rate is not programmed during earlyprintk - it is assumed
2186	 * that the previous boot loader has enabled required clocks and
2187	 * setup the baud rate generator hardware for us already.
2188	 */
2189	if (!port->uartclk) {
2190		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2191		goto done;
2192	}
2193
2194	for (i = 0; i < SCI_NUM_CLKS; i++)
2195		max_freq = max(max_freq, s->clk_rates[i]);
2196
2197	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2198	if (!baud)
2199		goto done;
2200
2201	/*
2202	 * There can be multiple sources for the sampling clock.  Find the one
2203	 * that gives us the smallest deviation from the desired baud rate.
2204	 */
2205
2206	/* Optional Undivided External Clock */
2207	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2208	    port->type != PORT_SCIFB) {
2209		err = sci_sck_calc(s, baud, &srr1);
2210		if (abs(err) < abs(min_err)) {
2211			best_clk = SCI_SCK;
2212			scr_val = SCSCR_CKE1;
2213			sccks = SCCKS_CKS;
2214			min_err = err;
2215			srr = srr1;
2216			if (!err)
2217				goto done;
2218		}
2219	}
2220
2221	/* Optional BRG Frequency Divided External Clock */
2222	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2223		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2224				   &srr1);
2225		if (abs(err) < abs(min_err)) {
2226			best_clk = SCI_SCIF_CLK;
2227			scr_val = SCSCR_CKE1;
2228			sccks = 0;
2229			min_err = err;
2230			dl = dl1;
2231			srr = srr1;
2232			if (!err)
2233				goto done;
2234		}
2235	}
2236
2237	/* Optional BRG Frequency Divided Internal Clock */
2238	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2239		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2240				   &srr1);
2241		if (abs(err) < abs(min_err)) {
2242			best_clk = SCI_BRG_INT;
2243			scr_val = SCSCR_CKE1;
2244			sccks = SCCKS_XIN;
2245			min_err = err;
2246			dl = dl1;
2247			srr = srr1;
2248			if (!min_err)
2249				goto done;
2250		}
2251	}
2252
2253	/* Divided Functional Clock using standard Bit Rate Register */
2254	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2255	if (abs(err) < abs(min_err)) {
2256		best_clk = SCI_FCK;
2257		scr_val = 0;
2258		min_err = err;
2259		brr = brr1;
2260		srr = srr1;
2261		cks = cks1;
2262	}
2263
2264done:
2265	if (best_clk >= 0)
2266		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2267			s->clks[best_clk], baud, min_err);
2268
2269	sci_port_enable(s);
2270
2271	/*
2272	 * Program the optional External Baud Rate Generator (BRG) first.
2273	 * It controls the mux to select (H)SCK or frequency divided clock.
2274	 */
2275	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2276		serial_port_out(port, SCDL, dl);
2277		serial_port_out(port, SCCKS, sccks);
2278	}
2279
 
 
2280	sci_reset(port);
2281
2282	uart_update_timeout(port, termios->c_cflag, baud);
2283
 
 
 
 
 
 
2284	if (best_clk >= 0) {
2285		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2286			switch (srr + 1) {
2287			case 5:  smr_val |= SCSMR_SRC_5;  break;
2288			case 7:  smr_val |= SCSMR_SRC_7;  break;
2289			case 11: smr_val |= SCSMR_SRC_11; break;
2290			case 13: smr_val |= SCSMR_SRC_13; break;
2291			case 16: smr_val |= SCSMR_SRC_16; break;
2292			case 17: smr_val |= SCSMR_SRC_17; break;
2293			case 19: smr_val |= SCSMR_SRC_19; break;
2294			case 27: smr_val |= SCSMR_SRC_27; break;
2295			}
2296		smr_val |= cks;
2297		dev_dbg(port->dev,
2298			 "SCR 0x%x SMR 0x%x BRR %u CKS 0x%x DL %u SRR %u\n",
2299			 scr_val, smr_val, brr, sccks, dl, srr);
2300		serial_port_out(port, SCSCR, scr_val);
2301		serial_port_out(port, SCSMR, smr_val);
2302		serial_port_out(port, SCBRR, brr);
2303		if (sci_getreg(port, HSSRR)->size)
2304			serial_port_out(port, HSSRR, srr | HSCIF_SRE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2305
2306		/* Wait one bit interval */
2307		udelay((1000000 + (baud - 1)) / baud);
2308	} else {
2309		/* Don't touch the bit rate configuration */
2310		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2311		smr_val |= serial_port_in(port, SCSMR) &
2312			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2313		dev_dbg(port->dev, "SCR 0x%x SMR 0x%x\n", scr_val, smr_val);
2314		serial_port_out(port, SCSCR, scr_val);
2315		serial_port_out(port, SCSMR, smr_val);
2316	}
2317
2318	sci_init_pins(port, termios->c_cflag);
2319
2320	port->status &= ~UPSTAT_AUTOCTS;
2321	s->autorts = false;
2322	reg = sci_getreg(port, SCFCR);
2323	if (reg->size) {
2324		unsigned short ctrl = serial_port_in(port, SCFCR);
2325
2326		if ((port->flags & UPF_HARD_FLOW) &&
2327		    (termios->c_cflag & CRTSCTS)) {
2328			/* There is no CTS interrupt to restart the hardware */
2329			port->status |= UPSTAT_AUTOCTS;
2330			/* MCE is enabled when RTS is raised */
2331			s->autorts = true;
2332		}
2333
2334		/*
2335		 * As we've done a sci_reset() above, ensure we don't
2336		 * interfere with the FIFOs while toggling MCE. As the
2337		 * reset values could still be set, simply mask them out.
2338		 */
2339		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2340
2341		serial_port_out(port, SCFCR, ctrl);
2342	}
 
 
 
 
2343
2344	scr_val |= s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0);
2345	dev_dbg(port->dev, "SCSCR 0x%x\n", scr_val);
2346	serial_port_out(port, SCSCR, scr_val);
 
 
 
 
 
 
2347	if ((srr + 1 == 5) &&
2348	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2349		/*
2350		 * In asynchronous mode, when the sampling rate is 1/5, first
2351		 * received data may become invalid on some SCIFA and SCIFB.
2352		 * To avoid this problem wait more than 1 serial data time (1
2353		 * bit time x serial data number) after setting SCSCR.RE = 1.
2354		 */
2355		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2356	}
2357
 
 
2358#ifdef CONFIG_SERIAL_SH_SCI_DMA
2359	/*
2360	 * Calculate delay for 2 DMA buffers (4 FIFO).
2361	 * See serial_core.c::uart_update_timeout().
2362	 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2363	 * function calculates 1 jiffie for the data plus 5 jiffies for the
2364	 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2365	 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2366	 * value obtained by this formula is too small. Therefore, if the value
2367	 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2368	 */
2369	if (s->chan_rx) {
2370		unsigned int bits;
2371
2372		/* byte size and parity */
2373		switch (termios->c_cflag & CSIZE) {
2374		case CS5:
2375			bits = 7;
2376			break;
2377		case CS6:
2378			bits = 8;
2379			break;
2380		case CS7:
2381			bits = 9;
2382			break;
2383		default:
2384			bits = 10;
2385			break;
2386		}
2387
2388		if (termios->c_cflag & CSTOPB)
2389			bits++;
2390		if (termios->c_cflag & PARENB)
2391			bits++;
2392		s->rx_timeout = DIV_ROUND_UP((s->buf_len_rx * 2 * bits * HZ) /
2393					     (baud / 10), 10);
2394		dev_dbg(port->dev, "DMA Rx t-out %ums, tty t-out %u jiffies\n",
2395			s->rx_timeout * 1000 / HZ, port->timeout);
2396		if (s->rx_timeout < msecs_to_jiffies(20))
2397			s->rx_timeout = msecs_to_jiffies(20);
2398	}
2399#endif
2400
2401	if ((termios->c_cflag & CREAD) != 0)
2402		sci_start_rx(port);
2403
 
 
2404	sci_port_disable(s);
2405
2406	if (UART_ENABLE_MS(port, termios->c_cflag))
2407		sci_enable_ms(port);
2408}
2409
2410static void sci_pm(struct uart_port *port, unsigned int state,
2411		   unsigned int oldstate)
2412{
2413	struct sci_port *sci_port = to_sci_port(port);
2414
2415	switch (state) {
2416	case UART_PM_STATE_OFF:
2417		sci_port_disable(sci_port);
2418		break;
2419	default:
2420		sci_port_enable(sci_port);
2421		break;
2422	}
2423}
2424
2425static const char *sci_type(struct uart_port *port)
2426{
2427	switch (port->type) {
2428	case PORT_IRDA:
2429		return "irda";
2430	case PORT_SCI:
2431		return "sci";
2432	case PORT_SCIF:
2433		return "scif";
2434	case PORT_SCIFA:
2435		return "scifa";
2436	case PORT_SCIFB:
2437		return "scifb";
2438	case PORT_HSCIF:
2439		return "hscif";
2440	}
2441
2442	return NULL;
2443}
2444
2445static int sci_remap_port(struct uart_port *port)
2446{
2447	struct sci_port *sport = to_sci_port(port);
2448
2449	/*
2450	 * Nothing to do if there's already an established membase.
2451	 */
2452	if (port->membase)
2453		return 0;
2454
2455	if (port->flags & UPF_IOREMAP) {
2456		port->membase = ioremap_nocache(port->mapbase, sport->reg_size);
2457		if (unlikely(!port->membase)) {
2458			dev_err(port->dev, "can't remap port#%d\n", port->line);
2459			return -ENXIO;
2460		}
2461	} else {
2462		/*
2463		 * For the simple (and majority of) cases where we don't
2464		 * need to do any remapping, just cast the cookie
2465		 * directly.
2466		 */
2467		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2468	}
2469
2470	return 0;
2471}
2472
2473static void sci_release_port(struct uart_port *port)
2474{
2475	struct sci_port *sport = to_sci_port(port);
2476
2477	if (port->flags & UPF_IOREMAP) {
2478		iounmap(port->membase);
2479		port->membase = NULL;
2480	}
2481
2482	release_mem_region(port->mapbase, sport->reg_size);
2483}
2484
2485static int sci_request_port(struct uart_port *port)
2486{
2487	struct resource *res;
2488	struct sci_port *sport = to_sci_port(port);
2489	int ret;
2490
2491	res = request_mem_region(port->mapbase, sport->reg_size,
2492				 dev_name(port->dev));
2493	if (unlikely(res == NULL)) {
2494		dev_err(port->dev, "request_mem_region failed.");
2495		return -EBUSY;
2496	}
2497
2498	ret = sci_remap_port(port);
2499	if (unlikely(ret != 0)) {
2500		release_resource(res);
2501		return ret;
2502	}
2503
2504	return 0;
2505}
2506
2507static void sci_config_port(struct uart_port *port, int flags)
2508{
2509	if (flags & UART_CONFIG_TYPE) {
2510		struct sci_port *sport = to_sci_port(port);
2511
2512		port->type = sport->cfg->type;
2513		sci_request_port(port);
2514	}
2515}
2516
2517static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2518{
2519	if (ser->baud_base < 2400)
2520		/* No paper tape reader for Mitch.. */
2521		return -EINVAL;
2522
2523	return 0;
2524}
2525
2526static const struct uart_ops sci_uart_ops = {
2527	.tx_empty	= sci_tx_empty,
2528	.set_mctrl	= sci_set_mctrl,
2529	.get_mctrl	= sci_get_mctrl,
2530	.start_tx	= sci_start_tx,
2531	.stop_tx	= sci_stop_tx,
2532	.stop_rx	= sci_stop_rx,
2533	.enable_ms	= sci_enable_ms,
2534	.break_ctl	= sci_break_ctl,
2535	.startup	= sci_startup,
2536	.shutdown	= sci_shutdown,
 
2537	.set_termios	= sci_set_termios,
2538	.pm		= sci_pm,
2539	.type		= sci_type,
2540	.release_port	= sci_release_port,
2541	.request_port	= sci_request_port,
2542	.config_port	= sci_config_port,
2543	.verify_port	= sci_verify_port,
2544#ifdef CONFIG_CONSOLE_POLL
2545	.poll_get_char	= sci_poll_get_char,
2546	.poll_put_char	= sci_poll_put_char,
2547#endif
2548};
2549
2550static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2551{
2552	const char *clk_names[] = {
2553		[SCI_FCK] = "fck",
2554		[SCI_SCK] = "sck",
2555		[SCI_BRG_INT] = "brg_int",
2556		[SCI_SCIF_CLK] = "scif_clk",
2557	};
2558	struct clk *clk;
2559	unsigned int i;
2560
2561	if (sci_port->cfg->type == PORT_HSCIF)
2562		clk_names[SCI_SCK] = "hsck";
2563
2564	for (i = 0; i < SCI_NUM_CLKS; i++) {
2565		clk = devm_clk_get(dev, clk_names[i]);
2566		if (PTR_ERR(clk) == -EPROBE_DEFER)
2567			return -EPROBE_DEFER;
2568
2569		if (IS_ERR(clk) && i == SCI_FCK) {
2570			/*
2571			 * "fck" used to be called "sci_ick", and we need to
2572			 * maintain DT backward compatibility.
2573			 */
2574			clk = devm_clk_get(dev, "sci_ick");
2575			if (PTR_ERR(clk) == -EPROBE_DEFER)
2576				return -EPROBE_DEFER;
2577
2578			if (!IS_ERR(clk))
2579				goto found;
2580
 
2581			/*
2582			 * Not all SH platforms declare a clock lookup entry
2583			 * for SCI devices, in which case we need to get the
2584			 * global "peripheral_clk" clock.
2585			 */
2586			clk = devm_clk_get(dev, "peripheral_clk");
2587			if (!IS_ERR(clk))
2588				goto found;
2589
2590			dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2591				PTR_ERR(clk));
2592			return PTR_ERR(clk);
2593		}
2594
2595found:
2596		if (IS_ERR(clk))
2597			dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2598				PTR_ERR(clk));
2599		else
2600			dev_dbg(dev, "clk %s is %pC rate %pCr\n", clk_names[i],
2601				clk, clk);
2602		sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2603	}
2604	return 0;
2605}
2606
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2607static int sci_init_single(struct platform_device *dev,
2608			   struct sci_port *sci_port, unsigned int index,
2609			   struct plat_sci_port *p, bool early)
2610{
2611	struct uart_port *port = &sci_port->port;
2612	const struct resource *res;
2613	unsigned int i;
2614	int ret;
2615
2616	sci_port->cfg	= p;
2617
2618	port->ops	= &sci_uart_ops;
2619	port->iotype	= UPIO_MEM;
2620	port->line	= index;
 
2621
2622	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2623	if (res == NULL)
2624		return -ENOMEM;
2625
2626	port->mapbase = res->start;
2627	sci_port->reg_size = resource_size(res);
2628
2629	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i)
2630		sci_port->irqs[i] = platform_get_irq(dev, i);
 
 
 
 
 
 
 
 
 
 
 
2631
2632	/* The SCI generates several interrupts. They can be muxed together or
2633	 * connected to different interrupt lines. In the muxed case only one
2634	 * interrupt resource is specified. In the non-muxed case three or four
2635	 * interrupt resources are specified, as the BRI interrupt is optional.
 
 
2636	 */
2637	if (sci_port->irqs[0] < 0)
2638		return -ENXIO;
2639
2640	if (sci_port->irqs[1] < 0) {
2641		sci_port->irqs[1] = sci_port->irqs[0];
2642		sci_port->irqs[2] = sci_port->irqs[0];
2643		sci_port->irqs[3] = sci_port->irqs[0];
2644	}
2645
2646	if (p->regtype == SCIx_PROBE_REGTYPE) {
2647		ret = sci_probe_regmap(p);
2648		if (unlikely(ret))
2649			return ret;
2650	}
2651
2652	switch (p->type) {
2653	case PORT_SCIFB:
2654		port->fifosize = 256;
2655		sci_port->overrun_reg = SCxSR;
2656		sci_port->overrun_mask = SCIFA_ORER;
2657		sci_port->sampling_rate_mask = SCI_SR_SCIFAB;
2658		break;
2659	case PORT_HSCIF:
2660		port->fifosize = 128;
2661		sci_port->overrun_reg = SCLSR;
2662		sci_port->overrun_mask = SCLSR_ORER;
2663		sci_port->sampling_rate_mask = SCI_SR_RANGE(8, 32);
2664		break;
2665	case PORT_SCIFA:
2666		port->fifosize = 64;
2667		sci_port->overrun_reg = SCxSR;
2668		sci_port->overrun_mask = SCIFA_ORER;
2669		sci_port->sampling_rate_mask = SCI_SR_SCIFAB;
2670		break;
2671	case PORT_SCIF:
2672		port->fifosize = 16;
2673		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE) {
2674			sci_port->overrun_reg = SCxSR;
2675			sci_port->overrun_mask = SCIFA_ORER;
2676			sci_port->sampling_rate_mask = SCI_SR(16);
2677		} else {
2678			sci_port->overrun_reg = SCLSR;
2679			sci_port->overrun_mask = SCLSR_ORER;
2680			sci_port->sampling_rate_mask = SCI_SR(32);
2681		}
2682		break;
2683	default:
2684		port->fifosize = 1;
2685		sci_port->overrun_reg = SCxSR;
2686		sci_port->overrun_mask = SCI_ORER;
2687		sci_port->sampling_rate_mask = SCI_SR(32);
2688		break;
2689	}
2690
 
 
 
2691	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2692	 * match the SoC datasheet, this should be investigated. Let platform
2693	 * data override the sampling rate for now.
2694	 */
2695	if (p->sampling_rate)
2696		sci_port->sampling_rate_mask = SCI_SR(p->sampling_rate);
 
2697
2698	if (!early) {
2699		ret = sci_init_clocks(sci_port, &dev->dev);
2700		if (ret < 0)
2701			return ret;
2702
2703		port->dev = &dev->dev;
2704
2705		pm_runtime_enable(&dev->dev);
2706	}
2707
2708	sci_port->break_timer.data = (unsigned long)sci_port;
2709	sci_port->break_timer.function = sci_break_timer;
2710	init_timer(&sci_port->break_timer);
2711
2712	/*
2713	 * Establish some sensible defaults for the error detection.
2714	 */
2715	if (p->type == PORT_SCI) {
2716		sci_port->error_mask = SCI_DEFAULT_ERROR_MASK;
2717		sci_port->error_clear = SCI_ERROR_CLEAR;
2718	} else {
2719		sci_port->error_mask = SCIF_DEFAULT_ERROR_MASK;
2720		sci_port->error_clear = SCIF_ERROR_CLEAR;
2721	}
2722
2723	/*
2724	 * Make the error mask inclusive of overrun detection, if
2725	 * supported.
2726	 */
2727	if (sci_port->overrun_reg == SCxSR) {
2728		sci_port->error_mask |= sci_port->overrun_mask;
2729		sci_port->error_clear &= ~sci_port->overrun_mask;
2730	}
2731
2732	port->type		= p->type;
2733	port->flags		= UPF_FIXED_PORT | p->flags;
2734	port->regshift		= p->regshift;
2735
2736	/*
2737	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2738	 * for the multi-IRQ ports, which is where we are primarily
2739	 * concerned with the shutdown path synchronization.
2740	 *
2741	 * For the muxed case there's nothing more to do.
2742	 */
2743	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
2744	port->irqflags		= 0;
2745
2746	port->serial_in		= sci_serial_in;
2747	port->serial_out	= sci_serial_out;
2748
2749	if (p->dma_slave_tx > 0 && p->dma_slave_rx > 0)
2750		dev_dbg(port->dev, "DMA tx %d, rx %d\n",
2751			p->dma_slave_tx, p->dma_slave_rx);
2752
2753	return 0;
2754}
2755
2756static void sci_cleanup_single(struct sci_port *port)
2757{
2758	pm_runtime_disable(port->port.dev);
2759}
2760
2761#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2762    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2763static void serial_console_putchar(struct uart_port *port, int ch)
2764{
2765	sci_poll_put_char(port, ch);
2766}
2767
2768/*
2769 *	Print a string to the serial port trying not to disturb
2770 *	any possible real use of the port...
2771 */
2772static void serial_console_write(struct console *co, const char *s,
2773				 unsigned count)
2774{
2775	struct sci_port *sci_port = &sci_ports[co->index];
2776	struct uart_port *port = &sci_port->port;
2777	unsigned short bits, ctrl, ctrl_temp;
2778	unsigned long flags;
2779	int locked = 1;
2780
2781	local_irq_save(flags);
2782#if defined(SUPPORT_SYSRQ)
2783	if (port->sysrq)
2784		locked = 0;
 
 
2785	else
2786#endif
2787	if (oops_in_progress)
2788		locked = spin_trylock(&port->lock);
2789	else
2790		spin_lock(&port->lock);
2791
2792	/* first save SCSCR then disable interrupts, keep clock source */
2793	ctrl = serial_port_in(port, SCSCR);
2794	ctrl_temp = (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
 
2795		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
2796	serial_port_out(port, SCSCR, ctrl_temp);
2797
2798	uart_console_write(port, s, count, serial_console_putchar);
2799
2800	/* wait until fifo is empty and last bit has been transmitted */
2801	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
2802	while ((serial_port_in(port, SCxSR) & bits) != bits)
2803		cpu_relax();
2804
2805	/* restore the SCSCR */
2806	serial_port_out(port, SCSCR, ctrl);
2807
2808	if (locked)
2809		spin_unlock(&port->lock);
2810	local_irq_restore(flags);
2811}
2812
2813static int serial_console_setup(struct console *co, char *options)
2814{
2815	struct sci_port *sci_port;
2816	struct uart_port *port;
2817	int baud = 115200;
2818	int bits = 8;
2819	int parity = 'n';
2820	int flow = 'n';
2821	int ret;
2822
2823	/*
2824	 * Refuse to handle any bogus ports.
2825	 */
2826	if (co->index < 0 || co->index >= SCI_NPORTS)
2827		return -ENODEV;
2828
2829	sci_port = &sci_ports[co->index];
2830	port = &sci_port->port;
2831
2832	/*
2833	 * Refuse to handle uninitialized ports.
2834	 */
2835	if (!port->ops)
2836		return -ENODEV;
2837
2838	ret = sci_remap_port(port);
2839	if (unlikely(ret != 0))
2840		return ret;
2841
2842	if (options)
2843		uart_parse_options(options, &baud, &parity, &bits, &flow);
2844
2845	return uart_set_options(port, co, baud, parity, bits, flow);
2846}
2847
2848static struct console serial_console = {
2849	.name		= "ttySC",
2850	.device		= uart_console_device,
2851	.write		= serial_console_write,
2852	.setup		= serial_console_setup,
2853	.flags		= CON_PRINTBUFFER,
2854	.index		= -1,
2855	.data		= &sci_uart_driver,
2856};
2857
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2858static struct console early_serial_console = {
2859	.name           = "early_ttySC",
2860	.write          = serial_console_write,
 
2861	.flags          = CON_PRINTBUFFER,
2862	.index		= -1,
2863};
2864
2865static char early_serial_buf[32];
2866
2867static int sci_probe_earlyprintk(struct platform_device *pdev)
2868{
2869	struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
2870
2871	if (early_serial_console.data)
2872		return -EEXIST;
2873
2874	early_serial_console.index = pdev->id;
2875
2876	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
2877
2878	serial_console_setup(&early_serial_console, early_serial_buf);
2879
2880	if (!strstr(early_serial_buf, "keep"))
2881		early_serial_console.flags |= CON_BOOT;
2882
2883	register_console(&early_serial_console);
2884	return 0;
2885}
 
2886
2887#define SCI_CONSOLE	(&serial_console)
2888
2889#else
2890static inline int sci_probe_earlyprintk(struct platform_device *pdev)
2891{
2892	return -EINVAL;
2893}
2894
2895#define SCI_CONSOLE	NULL
2896
2897#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
2898
2899static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
2900
 
2901static struct uart_driver sci_uart_driver = {
2902	.owner		= THIS_MODULE,
2903	.driver_name	= "sci",
2904	.dev_name	= "ttySC",
2905	.major		= SCI_MAJOR,
2906	.minor		= SCI_MINOR_START,
2907	.nr		= SCI_NPORTS,
2908	.cons		= SCI_CONSOLE,
2909};
2910
2911static int sci_remove(struct platform_device *dev)
2912{
2913	struct sci_port *port = platform_get_drvdata(dev);
 
2914
 
2915	uart_remove_one_port(&sci_uart_driver, &port->port);
2916
2917	sci_cleanup_single(port);
2918
2919	return 0;
 
 
 
2920}
2921
2922
2923#define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
2924#define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
2925#define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
2926
2927static const struct of_device_id of_sci_match[] = {
2928	/* SoC-specific types */
2929	{
2930		.compatible = "renesas,scif-r7s72100",
2931		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
2932	},
 
 
 
 
 
 
 
 
2933	/* Family-specific types */
2934	{
2935		.compatible = "renesas,rcar-gen1-scif",
2936		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
2937	}, {
2938		.compatible = "renesas,rcar-gen2-scif",
2939		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
2940	}, {
2941		.compatible = "renesas,rcar-gen3-scif",
2942		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
 
 
 
2943	},
2944	/* Generic types */
2945	{
2946		.compatible = "renesas,scif",
2947		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
2948	}, {
2949		.compatible = "renesas,scifa",
2950		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
2951	}, {
2952		.compatible = "renesas,scifb",
2953		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
2954	}, {
2955		.compatible = "renesas,hscif",
2956		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
2957	}, {
2958		.compatible = "renesas,sci",
2959		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
2960	}, {
2961		/* Terminator */
2962	},
2963};
2964MODULE_DEVICE_TABLE(of, of_sci_match);
2965
2966static struct plat_sci_port *
2967sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id)
 
 
 
 
 
2968{
2969	struct device_node *np = pdev->dev.of_node;
2970	const struct of_device_id *match;
2971	struct plat_sci_port *p;
2972	int id;
 
 
2973
2974	if (!IS_ENABLED(CONFIG_OF) || !np)
2975		return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
2976
2977	match = of_match_node(of_sci_match, np);
2978	if (!match)
2979		return NULL;
 
 
 
2980
2981	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
2982	if (!p)
2983		return NULL;
2984
2985	/* Get the line number from the aliases node. */
2986	id = of_alias_get_id(np, "serial");
 
 
2987	if (id < 0) {
2988		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
2989		return NULL;
 
 
 
 
2990	}
2991
 
2992	*dev_id = id;
2993
2994	p->flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
2995	p->type = SCI_OF_TYPE(match->data);
2996	p->regtype = SCI_OF_REGTYPE(match->data);
2997	p->scscr = SCSCR_RE | SCSCR_TE;
2998
2999	if (of_find_property(np, "uart-has-rtscts", NULL))
3000		p->capabilities |= SCIx_HAVE_RTSCTS;
3001
3002	return p;
3003}
3004
3005static int sci_probe_single(struct platform_device *dev,
3006				      unsigned int index,
3007				      struct plat_sci_port *p,
3008				      struct sci_port *sciport)
3009{
3010	int ret;
3011
3012	/* Sanity check */
3013	if (unlikely(index >= SCI_NPORTS)) {
3014		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3015			   index+1, SCI_NPORTS);
3016		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3017		return -EINVAL;
3018	}
 
 
 
 
 
 
 
 
 
 
 
 
 
3019
3020	ret = sci_init_single(dev, sciport, index, p, false);
3021	if (ret)
3022		return ret;
3023
3024	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3025	if (IS_ERR(sciport->gpios) && PTR_ERR(sciport->gpios) != -ENOSYS)
3026		return PTR_ERR(sciport->gpios);
3027
3028	if (p->capabilities & SCIx_HAVE_RTSCTS) {
3029		if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3030							UART_GPIO_CTS)) ||
3031		    !IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3032							UART_GPIO_RTS))) {
3033			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3034			return -EINVAL;
3035		}
3036		sciport->port.flags |= UPF_HARD_FLOW;
3037	}
3038
3039	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3040	if (ret) {
3041		sci_cleanup_single(sciport);
3042		return ret;
3043	}
3044
3045	return 0;
3046}
3047
3048static int sci_probe(struct platform_device *dev)
3049{
3050	struct plat_sci_port *p;
3051	struct sci_port *sp;
3052	unsigned int dev_id;
3053	int ret;
3054
3055	/*
3056	 * If we've come here via earlyprintk initialization, head off to
3057	 * the special early probe. We don't have sufficient device state
3058	 * to make it beyond this yet.
3059	 */
3060	if (is_early_platform_device(dev))
 
3061		return sci_probe_earlyprintk(dev);
 
3062
3063	if (dev->dev.of_node) {
3064		p = sci_parse_dt(dev, &dev_id);
3065		if (p == NULL)
3066			return -EINVAL;
3067	} else {
3068		p = dev->dev.platform_data;
3069		if (p == NULL) {
3070			dev_err(&dev->dev, "no platform data supplied\n");
3071			return -EINVAL;
3072		}
3073
3074		dev_id = dev->id;
3075	}
3076
3077	sp = &sci_ports[dev_id];
3078	platform_set_drvdata(dev, sp);
3079
3080	ret = sci_probe_single(dev, dev_id, p, sp);
3081	if (ret)
3082		return ret;
3083
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3084#ifdef CONFIG_SH_STANDARD_BIOS
3085	sh_bios_gdb_detach();
3086#endif
3087
 
3088	return 0;
3089}
3090
3091static __maybe_unused int sci_suspend(struct device *dev)
3092{
3093	struct sci_port *sport = dev_get_drvdata(dev);
3094
3095	if (sport)
3096		uart_suspend_port(&sci_uart_driver, &sport->port);
3097
3098	return 0;
3099}
3100
3101static __maybe_unused int sci_resume(struct device *dev)
3102{
3103	struct sci_port *sport = dev_get_drvdata(dev);
3104
3105	if (sport)
3106		uart_resume_port(&sci_uart_driver, &sport->port);
3107
3108	return 0;
3109}
3110
3111static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3112
3113static struct platform_driver sci_driver = {
3114	.probe		= sci_probe,
3115	.remove		= sci_remove,
3116	.driver		= {
3117		.name	= "sh-sci",
3118		.pm	= &sci_dev_pm_ops,
3119		.of_match_table = of_match_ptr(of_sci_match),
3120	},
3121};
3122
3123static int __init sci_init(void)
3124{
3125	int ret;
3126
3127	pr_info("%s\n", banner);
3128
3129	ret = uart_register_driver(&sci_uart_driver);
3130	if (likely(ret == 0)) {
3131		ret = platform_driver_register(&sci_driver);
3132		if (unlikely(ret))
3133			uart_unregister_driver(&sci_uart_driver);
3134	}
3135
3136	return ret;
3137}
3138
3139static void __exit sci_exit(void)
3140{
3141	platform_driver_unregister(&sci_driver);
3142	uart_unregister_driver(&sci_uart_driver);
 
 
3143}
3144
3145#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
3146early_platform_init_buffer("earlyprintk", &sci_driver,
3147			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3148#endif
3149#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3150static struct __init plat_sci_port port_cfg;
3151
3152static int __init early_console_setup(struct earlycon_device *device,
3153				      int type)
3154{
3155	if (!device->port.membase)
3156		return -ENODEV;
3157
3158	device->port.serial_in = sci_serial_in;
3159	device->port.serial_out	= sci_serial_out;
3160	device->port.type = type;
3161	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
 
3162	sci_ports[0].cfg = &port_cfg;
3163	sci_ports[0].cfg->type = type;
3164	sci_probe_regmap(sci_ports[0].cfg);
3165	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR) |
3166			 SCSCR_RE | SCSCR_TE;
3167	sci_serial_out(&sci_ports[0].port, SCSCR, port_cfg.scscr);
3168
3169	device->con->write = serial_console_write;
3170	return 0;
3171}
3172static int __init sci_early_console_setup(struct earlycon_device *device,
3173					  const char *opt)
3174{
3175	return early_console_setup(device, PORT_SCI);
3176}
3177static int __init scif_early_console_setup(struct earlycon_device *device,
3178					  const char *opt)
3179{
3180	return early_console_setup(device, PORT_SCIF);
3181}
 
 
 
 
 
 
 
3182static int __init scifa_early_console_setup(struct earlycon_device *device,
3183					  const char *opt)
3184{
3185	return early_console_setup(device, PORT_SCIFA);
3186}
3187static int __init scifb_early_console_setup(struct earlycon_device *device,
3188					  const char *opt)
3189{
3190	return early_console_setup(device, PORT_SCIFB);
3191}
3192static int __init hscif_early_console_setup(struct earlycon_device *device,
3193					  const char *opt)
3194{
3195	return early_console_setup(device, PORT_HSCIF);
3196}
3197
3198OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3199OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
 
 
3200OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3201OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3202OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3203#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3204
3205module_init(sci_init);
3206module_exit(sci_exit);
3207
3208MODULE_LICENSE("GPL");
3209MODULE_ALIAS("platform:sh-sci");
3210MODULE_AUTHOR("Paul Mundt");
3211MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");