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v5.4
   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#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  19#define SUPPORT_SYSRQ
  20#endif
  21
  22#undef DEBUG
  23
  24#include <linux/clk.h>
  25#include <linux/console.h>
  26#include <linux/ctype.h>
  27#include <linux/cpufreq.h>
  28#include <linux/delay.h>
  29#include <linux/dmaengine.h>
  30#include <linux/dma-mapping.h>
  31#include <linux/err.h>
  32#include <linux/errno.h>
  33#include <linux/init.h>
  34#include <linux/interrupt.h>
  35#include <linux/ioport.h>
  36#include <linux/ktime.h>
  37#include <linux/major.h>
  38#include <linux/module.h>
  39#include <linux/mm.h>
  40#include <linux/of.h>
  41#include <linux/of_device.h>
  42#include <linux/platform_device.h>
  43#include <linux/pm_runtime.h>
  44#include <linux/scatterlist.h>
  45#include <linux/serial.h>
  46#include <linux/serial_sci.h>
  47#include <linux/sh_dma.h>
  48#include <linux/slab.h>
  49#include <linux/string.h>
  50#include <linux/sysrq.h>
  51#include <linux/timer.h>
  52#include <linux/tty.h>
  53#include <linux/tty_flip.h>
  54
  55#ifdef CONFIG_SUPERH
  56#include <asm/sh_bios.h>
  57#endif
  58
  59#include "serial_mctrl_gpio.h"
  60#include "sh-sci.h"
  61
  62/* Offsets into the sci_port->irqs array */
  63enum {
  64	SCIx_ERI_IRQ,
  65	SCIx_RXI_IRQ,
  66	SCIx_TXI_IRQ,
  67	SCIx_BRI_IRQ,
  68	SCIx_DRI_IRQ,
  69	SCIx_TEI_IRQ,
  70	SCIx_NR_IRQS,
  71
  72	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
  73};
  74
  75#define SCIx_IRQ_IS_MUXED(port)			\
  76	((port)->irqs[SCIx_ERI_IRQ] ==	\
  77	 (port)->irqs[SCIx_RXI_IRQ]) ||	\
  78	((port)->irqs[SCIx_ERI_IRQ] &&	\
  79	 ((port)->irqs[SCIx_RXI_IRQ] < 0))
  80
  81enum SCI_CLKS {
  82	SCI_FCK,		/* Functional Clock */
  83	SCI_SCK,		/* Optional External Clock */
  84	SCI_BRG_INT,		/* Optional BRG Internal Clock Source */
  85	SCI_SCIF_CLK,		/* Optional BRG External Clock Source */
  86	SCI_NUM_CLKS
  87};
  88
  89/* Bit x set means sampling rate x + 1 is supported */
  90#define SCI_SR(x)		BIT((x) - 1)
  91#define SCI_SR_RANGE(x, y)	GENMASK((y) - 1, (x) - 1)
  92
  93#define SCI_SR_SCIFAB		SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
  94				SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
  95				SCI_SR(19) | SCI_SR(27)
  96
  97#define min_sr(_port)		ffs((_port)->sampling_rate_mask)
  98#define max_sr(_port)		fls((_port)->sampling_rate_mask)
  99
 100/* Iterate over all supported sampling rates, from high to low */
 101#define for_each_sr(_sr, _port)						\
 102	for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--)	\
 103		if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
 104
 105struct plat_sci_reg {
 106	u8 offset, size;
 107};
 108
 109struct sci_port_params {
 110	const struct plat_sci_reg regs[SCIx_NR_REGS];
 111	unsigned int fifosize;
 112	unsigned int overrun_reg;
 113	unsigned int overrun_mask;
 114	unsigned int sampling_rate_mask;
 115	unsigned int error_mask;
 116	unsigned int error_clear;
 117};
 118
 119struct sci_port {
 120	struct uart_port	port;
 121
 122	/* Platform configuration */
 123	const struct sci_port_params *params;
 124	const struct plat_sci_port *cfg;
 125	unsigned int		sampling_rate_mask;
 126	resource_size_t		reg_size;
 127	struct mctrl_gpios	*gpios;
 128
 129	/* Clocks */
 130	struct clk		*clks[SCI_NUM_CLKS];
 131	unsigned long		clk_rates[SCI_NUM_CLKS];
 132
 133	int			irqs[SCIx_NR_IRQS];
 134	char			*irqstr[SCIx_NR_IRQS];
 135
 136	struct dma_chan			*chan_tx;
 137	struct dma_chan			*chan_rx;
 138
 139#ifdef CONFIG_SERIAL_SH_SCI_DMA
 140	struct dma_chan			*chan_tx_saved;
 141	struct dma_chan			*chan_rx_saved;
 142	dma_cookie_t			cookie_tx;
 143	dma_cookie_t			cookie_rx[2];
 144	dma_cookie_t			active_rx;
 145	dma_addr_t			tx_dma_addr;
 146	unsigned int			tx_dma_len;
 147	struct scatterlist		sg_rx[2];
 148	void				*rx_buf[2];
 149	size_t				buf_len_rx;
 150	struct work_struct		work_tx;
 151	struct hrtimer			rx_timer;
 152	unsigned int			rx_timeout;	/* microseconds */
 153#endif
 154	unsigned int			rx_frame;
 155	int				rx_trigger;
 156	struct timer_list		rx_fifo_timer;
 157	int				rx_fifo_timeout;
 158	u16				hscif_tot;
 159
 160	bool has_rtscts;
 161	bool autorts;
 162};
 163
 164#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
 165
 166static struct sci_port sci_ports[SCI_NPORTS];
 167static unsigned long sci_ports_in_use;
 168static struct uart_driver sci_uart_driver;
 169
 170static inline struct sci_port *
 171to_sci_port(struct uart_port *uart)
 172{
 173	return container_of(uart, struct sci_port, port);
 174}
 175
 176static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
 177	/*
 178	 * Common SCI definitions, dependent on the port's regshift
 179	 * value.
 180	 */
 181	[SCIx_SCI_REGTYPE] = {
 182		.regs = {
 183			[SCSMR]		= { 0x00,  8 },
 184			[SCBRR]		= { 0x01,  8 },
 185			[SCSCR]		= { 0x02,  8 },
 186			[SCxTDR]	= { 0x03,  8 },
 187			[SCxSR]		= { 0x04,  8 },
 188			[SCxRDR]	= { 0x05,  8 },
 189		},
 190		.fifosize = 1,
 191		.overrun_reg = SCxSR,
 192		.overrun_mask = SCI_ORER,
 193		.sampling_rate_mask = SCI_SR(32),
 194		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 195		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 196	},
 197
 198	/*
 199	 * Common definitions for legacy IrDA ports.
 200	 */
 201	[SCIx_IRDA_REGTYPE] = {
 202		.regs = {
 203			[SCSMR]		= { 0x00,  8 },
 204			[SCBRR]		= { 0x02,  8 },
 205			[SCSCR]		= { 0x04,  8 },
 206			[SCxTDR]	= { 0x06,  8 },
 207			[SCxSR]		= { 0x08, 16 },
 208			[SCxRDR]	= { 0x0a,  8 },
 209			[SCFCR]		= { 0x0c,  8 },
 210			[SCFDR]		= { 0x0e, 16 },
 211		},
 212		.fifosize = 1,
 213		.overrun_reg = SCxSR,
 214		.overrun_mask = SCI_ORER,
 215		.sampling_rate_mask = SCI_SR(32),
 216		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 217		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 218	},
 219
 220	/*
 221	 * Common SCIFA definitions.
 222	 */
 223	[SCIx_SCIFA_REGTYPE] = {
 224		.regs = {
 225			[SCSMR]		= { 0x00, 16 },
 226			[SCBRR]		= { 0x04,  8 },
 227			[SCSCR]		= { 0x08, 16 },
 228			[SCxTDR]	= { 0x20,  8 },
 229			[SCxSR]		= { 0x14, 16 },
 230			[SCxRDR]	= { 0x24,  8 },
 231			[SCFCR]		= { 0x18, 16 },
 232			[SCFDR]		= { 0x1c, 16 },
 233			[SCPCR]		= { 0x30, 16 },
 234			[SCPDR]		= { 0x34, 16 },
 235		},
 236		.fifosize = 64,
 237		.overrun_reg = SCxSR,
 238		.overrun_mask = SCIFA_ORER,
 239		.sampling_rate_mask = SCI_SR_SCIFAB,
 240		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 241		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 242	},
 243
 244	/*
 245	 * Common SCIFB definitions.
 246	 */
 247	[SCIx_SCIFB_REGTYPE] = {
 248		.regs = {
 249			[SCSMR]		= { 0x00, 16 },
 250			[SCBRR]		= { 0x04,  8 },
 251			[SCSCR]		= { 0x08, 16 },
 252			[SCxTDR]	= { 0x40,  8 },
 253			[SCxSR]		= { 0x14, 16 },
 254			[SCxRDR]	= { 0x60,  8 },
 255			[SCFCR]		= { 0x18, 16 },
 256			[SCTFDR]	= { 0x38, 16 },
 257			[SCRFDR]	= { 0x3c, 16 },
 258			[SCPCR]		= { 0x30, 16 },
 259			[SCPDR]		= { 0x34, 16 },
 260		},
 261		.fifosize = 256,
 262		.overrun_reg = SCxSR,
 263		.overrun_mask = SCIFA_ORER,
 264		.sampling_rate_mask = SCI_SR_SCIFAB,
 265		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 266		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 267	},
 268
 269	/*
 270	 * Common SH-2(A) SCIF definitions for ports with FIFO data
 271	 * count registers.
 272	 */
 273	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
 274		.regs = {
 275			[SCSMR]		= { 0x00, 16 },
 276			[SCBRR]		= { 0x04,  8 },
 277			[SCSCR]		= { 0x08, 16 },
 278			[SCxTDR]	= { 0x0c,  8 },
 279			[SCxSR]		= { 0x10, 16 },
 280			[SCxRDR]	= { 0x14,  8 },
 281			[SCFCR]		= { 0x18, 16 },
 282			[SCFDR]		= { 0x1c, 16 },
 283			[SCSPTR]	= { 0x20, 16 },
 284			[SCLSR]		= { 0x24, 16 },
 285		},
 286		.fifosize = 16,
 287		.overrun_reg = SCLSR,
 288		.overrun_mask = SCLSR_ORER,
 289		.sampling_rate_mask = SCI_SR(32),
 290		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 291		.error_clear = SCIF_ERROR_CLEAR,
 292	},
 293
 294	/*
 295	 * The "SCIFA" that is in RZ/T and RZ/A2.
 296	 * It looks like a normal SCIF with FIFO data, but with a
 297	 * compressed address space. Also, the break out of interrupts
 298	 * are different: ERI/BRI, RXI, TXI, TEI, DRI.
 299	 */
 300	[SCIx_RZ_SCIFA_REGTYPE] = {
 301		.regs = {
 302			[SCSMR]		= { 0x00, 16 },
 303			[SCBRR]		= { 0x02,  8 },
 304			[SCSCR]		= { 0x04, 16 },
 305			[SCxTDR]	= { 0x06,  8 },
 306			[SCxSR]		= { 0x08, 16 },
 307			[SCxRDR]	= { 0x0A,  8 },
 308			[SCFCR]		= { 0x0C, 16 },
 309			[SCFDR]		= { 0x0E, 16 },
 310			[SCSPTR]	= { 0x10, 16 },
 311			[SCLSR]		= { 0x12, 16 },
 312		},
 313		.fifosize = 16,
 314		.overrun_reg = SCLSR,
 315		.overrun_mask = SCLSR_ORER,
 316		.sampling_rate_mask = SCI_SR(32),
 317		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 318		.error_clear = SCIF_ERROR_CLEAR,
 319	},
 320
 321	/*
 322	 * Common SH-3 SCIF definitions.
 323	 */
 324	[SCIx_SH3_SCIF_REGTYPE] = {
 325		.regs = {
 326			[SCSMR]		= { 0x00,  8 },
 327			[SCBRR]		= { 0x02,  8 },
 328			[SCSCR]		= { 0x04,  8 },
 329			[SCxTDR]	= { 0x06,  8 },
 330			[SCxSR]		= { 0x08, 16 },
 331			[SCxRDR]	= { 0x0a,  8 },
 332			[SCFCR]		= { 0x0c,  8 },
 333			[SCFDR]		= { 0x0e, 16 },
 334		},
 335		.fifosize = 16,
 336		.overrun_reg = SCLSR,
 337		.overrun_mask = SCLSR_ORER,
 338		.sampling_rate_mask = SCI_SR(32),
 339		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 340		.error_clear = SCIF_ERROR_CLEAR,
 341	},
 342
 343	/*
 344	 * Common SH-4(A) SCIF(B) definitions.
 345	 */
 346	[SCIx_SH4_SCIF_REGTYPE] = {
 347		.regs = {
 348			[SCSMR]		= { 0x00, 16 },
 349			[SCBRR]		= { 0x04,  8 },
 350			[SCSCR]		= { 0x08, 16 },
 351			[SCxTDR]	= { 0x0c,  8 },
 352			[SCxSR]		= { 0x10, 16 },
 353			[SCxRDR]	= { 0x14,  8 },
 354			[SCFCR]		= { 0x18, 16 },
 355			[SCFDR]		= { 0x1c, 16 },
 356			[SCSPTR]	= { 0x20, 16 },
 357			[SCLSR]		= { 0x24, 16 },
 358		},
 359		.fifosize = 16,
 360		.overrun_reg = SCLSR,
 361		.overrun_mask = SCLSR_ORER,
 362		.sampling_rate_mask = SCI_SR(32),
 363		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 364		.error_clear = SCIF_ERROR_CLEAR,
 365	},
 366
 367	/*
 368	 * Common SCIF definitions for ports with a Baud Rate Generator for
 369	 * External Clock (BRG).
 370	 */
 371	[SCIx_SH4_SCIF_BRG_REGTYPE] = {
 372		.regs = {
 373			[SCSMR]		= { 0x00, 16 },
 374			[SCBRR]		= { 0x04,  8 },
 375			[SCSCR]		= { 0x08, 16 },
 376			[SCxTDR]	= { 0x0c,  8 },
 377			[SCxSR]		= { 0x10, 16 },
 378			[SCxRDR]	= { 0x14,  8 },
 379			[SCFCR]		= { 0x18, 16 },
 380			[SCFDR]		= { 0x1c, 16 },
 381			[SCSPTR]	= { 0x20, 16 },
 382			[SCLSR]		= { 0x24, 16 },
 383			[SCDL]		= { 0x30, 16 },
 384			[SCCKS]		= { 0x34, 16 },
 385		},
 386		.fifosize = 16,
 387		.overrun_reg = SCLSR,
 388		.overrun_mask = SCLSR_ORER,
 389		.sampling_rate_mask = SCI_SR(32),
 390		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 391		.error_clear = SCIF_ERROR_CLEAR,
 392	},
 393
 394	/*
 395	 * Common HSCIF definitions.
 396	 */
 397	[SCIx_HSCIF_REGTYPE] = {
 398		.regs = {
 399			[SCSMR]		= { 0x00, 16 },
 400			[SCBRR]		= { 0x04,  8 },
 401			[SCSCR]		= { 0x08, 16 },
 402			[SCxTDR]	= { 0x0c,  8 },
 403			[SCxSR]		= { 0x10, 16 },
 404			[SCxRDR]	= { 0x14,  8 },
 405			[SCFCR]		= { 0x18, 16 },
 406			[SCFDR]		= { 0x1c, 16 },
 407			[SCSPTR]	= { 0x20, 16 },
 408			[SCLSR]		= { 0x24, 16 },
 409			[HSSRR]		= { 0x40, 16 },
 410			[SCDL]		= { 0x30, 16 },
 411			[SCCKS]		= { 0x34, 16 },
 412			[HSRTRGR]	= { 0x54, 16 },
 413			[HSTTRGR]	= { 0x58, 16 },
 414		},
 415		.fifosize = 128,
 416		.overrun_reg = SCLSR,
 417		.overrun_mask = SCLSR_ORER,
 418		.sampling_rate_mask = SCI_SR_RANGE(8, 32),
 419		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 420		.error_clear = SCIF_ERROR_CLEAR,
 421	},
 422
 423	/*
 424	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
 425	 * register.
 426	 */
 427	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
 428		.regs = {
 429			[SCSMR]		= { 0x00, 16 },
 430			[SCBRR]		= { 0x04,  8 },
 431			[SCSCR]		= { 0x08, 16 },
 432			[SCxTDR]	= { 0x0c,  8 },
 433			[SCxSR]		= { 0x10, 16 },
 434			[SCxRDR]	= { 0x14,  8 },
 435			[SCFCR]		= { 0x18, 16 },
 436			[SCFDR]		= { 0x1c, 16 },
 437			[SCLSR]		= { 0x24, 16 },
 438		},
 439		.fifosize = 16,
 440		.overrun_reg = SCLSR,
 441		.overrun_mask = SCLSR_ORER,
 442		.sampling_rate_mask = SCI_SR(32),
 443		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 444		.error_clear = SCIF_ERROR_CLEAR,
 445	},
 446
 447	/*
 448	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
 449	 * count registers.
 450	 */
 451	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
 452		.regs = {
 453			[SCSMR]		= { 0x00, 16 },
 454			[SCBRR]		= { 0x04,  8 },
 455			[SCSCR]		= { 0x08, 16 },
 456			[SCxTDR]	= { 0x0c,  8 },
 457			[SCxSR]		= { 0x10, 16 },
 458			[SCxRDR]	= { 0x14,  8 },
 459			[SCFCR]		= { 0x18, 16 },
 460			[SCFDR]		= { 0x1c, 16 },
 461			[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
 462			[SCRFDR]	= { 0x20, 16 },
 463			[SCSPTR]	= { 0x24, 16 },
 464			[SCLSR]		= { 0x28, 16 },
 465		},
 466		.fifosize = 16,
 467		.overrun_reg = SCLSR,
 468		.overrun_mask = SCLSR_ORER,
 469		.sampling_rate_mask = SCI_SR(32),
 470		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 471		.error_clear = SCIF_ERROR_CLEAR,
 472	},
 473
 474	/*
 475	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
 476	 * registers.
 477	 */
 478	[SCIx_SH7705_SCIF_REGTYPE] = {
 479		.regs = {
 480			[SCSMR]		= { 0x00, 16 },
 481			[SCBRR]		= { 0x04,  8 },
 482			[SCSCR]		= { 0x08, 16 },
 483			[SCxTDR]	= { 0x20,  8 },
 484			[SCxSR]		= { 0x14, 16 },
 485			[SCxRDR]	= { 0x24,  8 },
 486			[SCFCR]		= { 0x18, 16 },
 487			[SCFDR]		= { 0x1c, 16 },
 488		},
 489		.fifosize = 64,
 490		.overrun_reg = SCxSR,
 491		.overrun_mask = SCIFA_ORER,
 492		.sampling_rate_mask = SCI_SR(16),
 493		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 494		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 495	},
 496};
 497
 498#define sci_getreg(up, offset)		(&to_sci_port(up)->params->regs[offset])
 499
 500/*
 501 * The "offset" here is rather misleading, in that it refers to an enum
 502 * value relative to the port mapping rather than the fixed offset
 503 * itself, which needs to be manually retrieved from the platform's
 504 * register map for the given port.
 505 */
 506static unsigned int sci_serial_in(struct uart_port *p, int offset)
 507{
 508	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 509
 510	if (reg->size == 8)
 511		return ioread8(p->membase + (reg->offset << p->regshift));
 512	else if (reg->size == 16)
 513		return ioread16(p->membase + (reg->offset << p->regshift));
 514	else
 515		WARN(1, "Invalid register access\n");
 516
 517	return 0;
 518}
 519
 520static void sci_serial_out(struct uart_port *p, int offset, int value)
 521{
 522	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 523
 524	if (reg->size == 8)
 525		iowrite8(value, p->membase + (reg->offset << p->regshift));
 526	else if (reg->size == 16)
 527		iowrite16(value, p->membase + (reg->offset << p->regshift));
 528	else
 529		WARN(1, "Invalid register access\n");
 530}
 531
 532static void sci_port_enable(struct sci_port *sci_port)
 533{
 534	unsigned int i;
 535
 536	if (!sci_port->port.dev)
 537		return;
 538
 539	pm_runtime_get_sync(sci_port->port.dev);
 540
 541	for (i = 0; i < SCI_NUM_CLKS; i++) {
 542		clk_prepare_enable(sci_port->clks[i]);
 543		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
 544	}
 545	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
 546}
 547
 548static void sci_port_disable(struct sci_port *sci_port)
 549{
 550	unsigned int i;
 551
 552	if (!sci_port->port.dev)
 553		return;
 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)->params->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 data = serial_port_in(port, SCPDR);
 719		u16 ctrl = serial_port_in(port, SCPCR);
 720
 721		/* Enable RXD and TXD pin functions */
 722		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
 723		if (to_sci_port(port)->has_rtscts) {
 724			/* RTS# is output, active low, unless autorts */
 725			if (!(port->mctrl & TIOCM_RTS)) {
 726				ctrl |= SCPCR_RTSC;
 727				data |= SCPDR_RTSD;
 728			} else if (!s->autorts) {
 729				ctrl |= SCPCR_RTSC;
 730				data &= ~SCPDR_RTSD;
 731			} else {
 732				/* Enable RTS# pin function */
 733				ctrl &= ~SCPCR_RTSC;
 734			}
 735			/* Enable CTS# pin function */
 736			ctrl &= ~SCPCR_CTSC;
 737		}
 738		serial_port_out(port, SCPDR, data);
 739		serial_port_out(port, SCPCR, ctrl);
 740	} else if (sci_getreg(port, SCSPTR)->size) {
 741		u16 status = serial_port_in(port, SCSPTR);
 742
 743		/* RTS# is always output; and active low, unless autorts */
 744		status |= SCSPTR_RTSIO;
 745		if (!(port->mctrl & TIOCM_RTS))
 746			status |= SCSPTR_RTSDT;
 747		else if (!s->autorts)
 748			status &= ~SCSPTR_RTSDT;
 749		/* CTS# and SCK are inputs */
 750		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
 751		serial_port_out(port, SCSPTR, status);
 752	}
 753}
 754
 755static int sci_txfill(struct uart_port *port)
 756{
 757	struct sci_port *s = to_sci_port(port);
 758	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 759	const struct plat_sci_reg *reg;
 760
 761	reg = sci_getreg(port, SCTFDR);
 762	if (reg->size)
 763		return serial_port_in(port, SCTFDR) & fifo_mask;
 764
 765	reg = sci_getreg(port, SCFDR);
 766	if (reg->size)
 767		return serial_port_in(port, SCFDR) >> 8;
 768
 769	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
 770}
 771
 772static int sci_txroom(struct uart_port *port)
 773{
 774	return port->fifosize - sci_txfill(port);
 775}
 776
 777static int sci_rxfill(struct uart_port *port)
 778{
 779	struct sci_port *s = to_sci_port(port);
 780	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 781	const struct plat_sci_reg *reg;
 782
 783	reg = sci_getreg(port, SCRFDR);
 784	if (reg->size)
 785		return serial_port_in(port, SCRFDR) & fifo_mask;
 786
 787	reg = sci_getreg(port, SCFDR);
 788	if (reg->size)
 789		return serial_port_in(port, SCFDR) & fifo_mask;
 790
 791	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
 792}
 793
 794/* ********************************************************************** *
 795 *                   the interrupt related routines                       *
 796 * ********************************************************************** */
 797
 798static void sci_transmit_chars(struct uart_port *port)
 799{
 800	struct circ_buf *xmit = &port->state->xmit;
 801	unsigned int stopped = uart_tx_stopped(port);
 802	unsigned short status;
 803	unsigned short ctrl;
 804	int count;
 805
 806	status = serial_port_in(port, SCxSR);
 807	if (!(status & SCxSR_TDxE(port))) {
 808		ctrl = serial_port_in(port, SCSCR);
 809		if (uart_circ_empty(xmit))
 810			ctrl &= ~SCSCR_TIE;
 811		else
 812			ctrl |= SCSCR_TIE;
 813		serial_port_out(port, SCSCR, ctrl);
 814		return;
 815	}
 816
 817	count = sci_txroom(port);
 818
 819	do {
 820		unsigned char c;
 821
 822		if (port->x_char) {
 823			c = port->x_char;
 824			port->x_char = 0;
 825		} else if (!uart_circ_empty(xmit) && !stopped) {
 826			c = xmit->buf[xmit->tail];
 827			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 828		} else {
 829			break;
 830		}
 831
 832		serial_port_out(port, SCxTDR, c);
 833
 834		port->icount.tx++;
 835	} while (--count > 0);
 836
 837	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
 838
 839	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 840		uart_write_wakeup(port);
 841	if (uart_circ_empty(xmit))
 842		sci_stop_tx(port);
 
 
 
 
 
 
 
 843
 
 
 
 844}
 845
 846/* On SH3, SCIF may read end-of-break as a space->mark char */
 847#define STEPFN(c)  ({int __c = (c); (((__c-1)|(__c)) == -1); })
 848
 849static void sci_receive_chars(struct uart_port *port)
 850{
 851	struct tty_port *tport = &port->state->port;
 852	int i, count, copied = 0;
 853	unsigned short status;
 854	unsigned char flag;
 855
 856	status = serial_port_in(port, SCxSR);
 857	if (!(status & SCxSR_RDxF(port)))
 858		return;
 859
 860	while (1) {
 861		/* Don't copy more bytes than there is room for in the buffer */
 862		count = tty_buffer_request_room(tport, sci_rxfill(port));
 863
 864		/* If for any reason we can't copy more data, we're done! */
 865		if (count == 0)
 866			break;
 867
 868		if (port->type == PORT_SCI) {
 869			char c = serial_port_in(port, SCxRDR);
 870			if (uart_handle_sysrq_char(port, c))
 871				count = 0;
 872			else
 873				tty_insert_flip_char(tport, c, TTY_NORMAL);
 874		} else {
 875			for (i = 0; i < count; i++) {
 876				char c = serial_port_in(port, SCxRDR);
 877
 878				status = serial_port_in(port, SCxSR);
 879				if (uart_handle_sysrq_char(port, c)) {
 880					count--; i--;
 881					continue;
 882				}
 883
 884				/* Store data and status */
 885				if (status & SCxSR_FER(port)) {
 886					flag = TTY_FRAME;
 887					port->icount.frame++;
 888					dev_notice(port->dev, "frame error\n");
 889				} else if (status & SCxSR_PER(port)) {
 890					flag = TTY_PARITY;
 891					port->icount.parity++;
 892					dev_notice(port->dev, "parity error\n");
 893				} else
 894					flag = TTY_NORMAL;
 895
 896				tty_insert_flip_char(tport, c, flag);
 897			}
 898		}
 899
 900		serial_port_in(port, SCxSR); /* dummy read */
 901		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 902
 903		copied += count;
 904		port->icount.rx += count;
 905	}
 906
 907	if (copied) {
 908		/* Tell the rest of the system the news. New characters! */
 909		tty_flip_buffer_push(tport);
 910	} else {
 911		/* TTY buffers full; read from RX reg to prevent lockup */
 912		serial_port_in(port, SCxRDR);
 913		serial_port_in(port, SCxSR); /* dummy read */
 914		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 915	}
 916}
 917
 918static int sci_handle_errors(struct uart_port *port)
 919{
 920	int copied = 0;
 921	unsigned short status = serial_port_in(port, SCxSR);
 922	struct tty_port *tport = &port->state->port;
 923	struct sci_port *s = to_sci_port(port);
 924
 925	/* Handle overruns */
 926	if (status & s->params->overrun_mask) {
 927		port->icount.overrun++;
 928
 929		/* overrun error */
 930		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
 931			copied++;
 932
 933		dev_notice(port->dev, "overrun error\n");
 934	}
 935
 936	if (status & SCxSR_FER(port)) {
 937		/* frame error */
 938		port->icount.frame++;
 939
 940		if (tty_insert_flip_char(tport, 0, TTY_FRAME))
 941			copied++;
 942
 943		dev_notice(port->dev, "frame error\n");
 944	}
 945
 946	if (status & SCxSR_PER(port)) {
 947		/* parity error */
 948		port->icount.parity++;
 949
 950		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
 951			copied++;
 952
 953		dev_notice(port->dev, "parity error\n");
 954	}
 955
 956	if (copied)
 957		tty_flip_buffer_push(tport);
 958
 959	return copied;
 960}
 961
 962static int sci_handle_fifo_overrun(struct uart_port *port)
 963{
 964	struct tty_port *tport = &port->state->port;
 965	struct sci_port *s = to_sci_port(port);
 966	const struct plat_sci_reg *reg;
 967	int copied = 0;
 968	u16 status;
 969
 970	reg = sci_getreg(port, s->params->overrun_reg);
 971	if (!reg->size)
 972		return 0;
 973
 974	status = serial_port_in(port, s->params->overrun_reg);
 975	if (status & s->params->overrun_mask) {
 976		status &= ~s->params->overrun_mask;
 977		serial_port_out(port, s->params->overrun_reg, status);
 978
 979		port->icount.overrun++;
 980
 981		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 982		tty_flip_buffer_push(tport);
 983
 984		dev_dbg(port->dev, "overrun error\n");
 985		copied++;
 986	}
 987
 988	return copied;
 989}
 990
 991static int sci_handle_breaks(struct uart_port *port)
 992{
 993	int copied = 0;
 994	unsigned short status = serial_port_in(port, SCxSR);
 995	struct tty_port *tport = &port->state->port;
 996
 997	if (uart_handle_break(port))
 998		return 0;
 999
1000	if (status & SCxSR_BRK(port)) {
1001		port->icount.brk++;
1002
1003		/* Notify of BREAK */
1004		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1005			copied++;
1006
1007		dev_dbg(port->dev, "BREAK detected\n");
1008	}
1009
1010	if (copied)
1011		tty_flip_buffer_push(tport);
1012
1013	copied += sci_handle_fifo_overrun(port);
1014
1015	return copied;
1016}
1017
1018static int scif_set_rtrg(struct uart_port *port, int rx_trig)
1019{
1020	unsigned int bits;
1021
1022	if (rx_trig < 1)
1023		rx_trig = 1;
1024	if (rx_trig >= port->fifosize)
1025		rx_trig = port->fifosize;
1026
1027	/* HSCIF can be set to an arbitrary level. */
1028	if (sci_getreg(port, HSRTRGR)->size) {
1029		serial_port_out(port, HSRTRGR, rx_trig);
1030		return rx_trig;
1031	}
1032
1033	switch (port->type) {
1034	case PORT_SCIF:
1035		if (rx_trig < 4) {
1036			bits = 0;
1037			rx_trig = 1;
1038		} else if (rx_trig < 8) {
1039			bits = SCFCR_RTRG0;
1040			rx_trig = 4;
1041		} else if (rx_trig < 14) {
1042			bits = SCFCR_RTRG1;
1043			rx_trig = 8;
1044		} else {
1045			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1046			rx_trig = 14;
1047		}
1048		break;
1049	case PORT_SCIFA:
1050	case PORT_SCIFB:
1051		if (rx_trig < 16) {
1052			bits = 0;
1053			rx_trig = 1;
1054		} else if (rx_trig < 32) {
1055			bits = SCFCR_RTRG0;
1056			rx_trig = 16;
1057		} else if (rx_trig < 48) {
1058			bits = SCFCR_RTRG1;
1059			rx_trig = 32;
1060		} else {
1061			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1062			rx_trig = 48;
1063		}
1064		break;
1065	default:
1066		WARN(1, "unknown FIFO configuration");
1067		return 1;
1068	}
1069
1070	serial_port_out(port, SCFCR,
1071		(serial_port_in(port, SCFCR) &
1072		~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1073
1074	return rx_trig;
1075}
1076
1077static int scif_rtrg_enabled(struct uart_port *port)
1078{
1079	if (sci_getreg(port, HSRTRGR)->size)
1080		return serial_port_in(port, HSRTRGR) != 0;
1081	else
1082		return (serial_port_in(port, SCFCR) &
1083			(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1084}
1085
1086static void rx_fifo_timer_fn(struct timer_list *t)
1087{
1088	struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1089	struct uart_port *port = &s->port;
1090
1091	dev_dbg(port->dev, "Rx timed out\n");
1092	scif_set_rtrg(port, 1);
1093}
1094
1095static ssize_t rx_fifo_trigger_show(struct device *dev,
1096				    struct device_attribute *attr, char *buf)
 
1097{
1098	struct uart_port *port = dev_get_drvdata(dev);
1099	struct sci_port *sci = to_sci_port(port);
1100
1101	return sprintf(buf, "%d\n", sci->rx_trigger);
1102}
1103
1104static ssize_t rx_fifo_trigger_store(struct device *dev,
1105				     struct device_attribute *attr,
1106				     const char *buf, size_t count)
 
1107{
1108	struct uart_port *port = dev_get_drvdata(dev);
1109	struct sci_port *sci = to_sci_port(port);
1110	int ret;
1111	long r;
1112
1113	ret = kstrtol(buf, 0, &r);
1114	if (ret)
1115		return ret;
1116
1117	sci->rx_trigger = scif_set_rtrg(port, r);
1118	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1119		scif_set_rtrg(port, 1);
1120
1121	return count;
1122}
1123
1124static DEVICE_ATTR_RW(rx_fifo_trigger);
1125
1126static ssize_t rx_fifo_timeout_show(struct device *dev,
1127			       struct device_attribute *attr,
1128			       char *buf)
1129{
1130	struct uart_port *port = dev_get_drvdata(dev);
1131	struct sci_port *sci = to_sci_port(port);
1132	int v;
1133
1134	if (port->type == PORT_HSCIF)
1135		v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1136	else
1137		v = sci->rx_fifo_timeout;
1138
1139	return sprintf(buf, "%d\n", v);
1140}
1141
1142static ssize_t rx_fifo_timeout_store(struct device *dev,
1143				struct device_attribute *attr,
1144				const char *buf,
1145				size_t count)
1146{
1147	struct uart_port *port = dev_get_drvdata(dev);
1148	struct sci_port *sci = to_sci_port(port);
1149	int ret;
1150	long r;
1151
1152	ret = kstrtol(buf, 0, &r);
1153	if (ret)
1154		return ret;
1155
1156	if (port->type == PORT_HSCIF) {
1157		if (r < 0 || r > 3)
1158			return -EINVAL;
1159		sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1160	} else {
1161		sci->rx_fifo_timeout = r;
1162		scif_set_rtrg(port, 1);
1163		if (r > 0)
1164			timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1165	}
1166
1167	return count;
1168}
1169
1170static DEVICE_ATTR_RW(rx_fifo_timeout);
1171
1172
1173#ifdef CONFIG_SERIAL_SH_SCI_DMA
1174static void sci_dma_tx_complete(void *arg)
1175{
1176	struct sci_port *s = arg;
1177	struct uart_port *port = &s->port;
1178	struct circ_buf *xmit = &port->state->xmit;
1179	unsigned long flags;
1180
1181	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1182
1183	spin_lock_irqsave(&port->lock, flags);
1184
1185	xmit->tail += s->tx_dma_len;
1186	xmit->tail &= UART_XMIT_SIZE - 1;
1187
1188	port->icount.tx += s->tx_dma_len;
1189
1190	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1191		uart_write_wakeup(port);
1192
1193	if (!uart_circ_empty(xmit)) {
1194		s->cookie_tx = 0;
1195		schedule_work(&s->work_tx);
1196	} else {
1197		s->cookie_tx = -EINVAL;
1198		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1199			u16 ctrl = serial_port_in(port, SCSCR);
1200			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1201		}
1202	}
1203
1204	spin_unlock_irqrestore(&port->lock, flags);
1205}
1206
1207/* Locking: called with port lock held */
1208static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1209{
1210	struct uart_port *port = &s->port;
1211	struct tty_port *tport = &port->state->port;
1212	int copied;
1213
1214	copied = tty_insert_flip_string(tport, buf, count);
1215	if (copied < count)
1216		port->icount.buf_overrun++;
1217
1218	port->icount.rx += copied;
1219
1220	return copied;
1221}
1222
1223static int sci_dma_rx_find_active(struct sci_port *s)
1224{
1225	unsigned int i;
1226
1227	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1228		if (s->active_rx == s->cookie_rx[i])
1229			return i;
1230
1231	return -1;
1232}
1233
1234static void sci_dma_rx_chan_invalidate(struct sci_port *s)
1235{
1236	unsigned int i;
 
 
1237
 
1238	s->chan_rx = NULL;
1239	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1240		s->cookie_rx[i] = -EINVAL;
1241	s->active_rx = 0;
1242}
1243
1244static void sci_dma_rx_release(struct sci_port *s)
1245{
1246	struct dma_chan *chan = s->chan_rx_saved;
1247
1248	s->chan_rx_saved = NULL;
1249	sci_dma_rx_chan_invalidate(s);
1250	dmaengine_terminate_sync(chan);
1251	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1252			  sg_dma_address(&s->sg_rx[0]));
1253	dma_release_channel(chan);
 
 
 
 
 
1254}
1255
1256static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1257{
1258	long sec = usec / 1000000;
1259	long nsec = (usec % 1000000) * 1000;
1260	ktime_t t = ktime_set(sec, nsec);
1261
1262	hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1263}
1264
1265static void sci_dma_rx_reenable_irq(struct sci_port *s)
1266{
1267	struct uart_port *port = &s->port;
1268	u16 scr;
1269
1270	/* Direct new serial port interrupts back to CPU */
1271	scr = serial_port_in(port, SCSCR);
1272	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1273		scr &= ~SCSCR_RDRQE;
1274		enable_irq(s->irqs[SCIx_RXI_IRQ]);
1275	}
1276	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1277}
1278
1279static void sci_dma_rx_complete(void *arg)
1280{
1281	struct sci_port *s = arg;
1282	struct dma_chan *chan = s->chan_rx;
1283	struct uart_port *port = &s->port;
1284	struct dma_async_tx_descriptor *desc;
1285	unsigned long flags;
1286	int active, count = 0;
1287
1288	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1289		s->active_rx);
1290
1291	spin_lock_irqsave(&port->lock, flags);
1292
1293	active = sci_dma_rx_find_active(s);
1294	if (active >= 0)
1295		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1296
1297	start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1298
1299	if (count)
1300		tty_flip_buffer_push(&port->state->port);
1301
1302	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1303				       DMA_DEV_TO_MEM,
1304				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1305	if (!desc)
1306		goto fail;
1307
1308	desc->callback = sci_dma_rx_complete;
1309	desc->callback_param = s;
1310	s->cookie_rx[active] = dmaengine_submit(desc);
1311	if (dma_submit_error(s->cookie_rx[active]))
1312		goto fail;
1313
1314	s->active_rx = s->cookie_rx[!active];
1315
1316	dma_async_issue_pending(chan);
1317
1318	spin_unlock_irqrestore(&port->lock, flags);
1319	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1320		__func__, s->cookie_rx[active], active, s->active_rx);
1321	return;
1322
1323fail:
1324	spin_unlock_irqrestore(&port->lock, flags);
1325	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1326	/* Switch to PIO */
1327	spin_lock_irqsave(&port->lock, flags);
1328	dmaengine_terminate_async(chan);
1329	sci_dma_rx_chan_invalidate(s);
1330	sci_dma_rx_reenable_irq(s);
1331	spin_unlock_irqrestore(&port->lock, flags);
1332}
1333
1334static void sci_dma_tx_release(struct sci_port *s)
1335{
1336	struct dma_chan *chan = s->chan_tx_saved;
 
 
1337
1338	cancel_work_sync(&s->work_tx);
1339	s->chan_tx_saved = s->chan_tx = NULL;
1340	s->cookie_tx = -EINVAL;
1341	dmaengine_terminate_sync(chan);
 
1342	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1343			 DMA_TO_DEVICE);
1344	dma_release_channel(chan);
 
 
 
 
 
1345}
1346
1347static int sci_dma_rx_submit(struct sci_port *s, bool port_lock_held)
1348{
1349	struct dma_chan *chan = s->chan_rx;
1350	struct uart_port *port = &s->port;
1351	unsigned long flags;
1352	int i;
1353
1354	for (i = 0; i < 2; i++) {
1355		struct scatterlist *sg = &s->sg_rx[i];
1356		struct dma_async_tx_descriptor *desc;
1357
1358		desc = dmaengine_prep_slave_sg(chan,
1359			sg, 1, DMA_DEV_TO_MEM,
1360			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1361		if (!desc)
1362			goto fail;
1363
1364		desc->callback = sci_dma_rx_complete;
1365		desc->callback_param = s;
1366		s->cookie_rx[i] = dmaengine_submit(desc);
1367		if (dma_submit_error(s->cookie_rx[i]))
1368			goto fail;
1369
1370	}
1371
1372	s->active_rx = s->cookie_rx[0];
1373
1374	dma_async_issue_pending(chan);
1375	return 0;
1376
1377fail:
1378	/* Switch to PIO */
1379	if (!port_lock_held)
1380		spin_lock_irqsave(&port->lock, flags);
1381	if (i)
1382		dmaengine_terminate_async(chan);
1383	sci_dma_rx_chan_invalidate(s);
1384	sci_start_rx(port);
1385	if (!port_lock_held)
1386		spin_unlock_irqrestore(&port->lock, flags);
1387	return -EAGAIN;
1388}
1389
1390static void sci_dma_tx_work_fn(struct work_struct *work)
1391{
1392	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1393	struct dma_async_tx_descriptor *desc;
1394	struct dma_chan *chan = s->chan_tx;
1395	struct uart_port *port = &s->port;
1396	struct circ_buf *xmit = &port->state->xmit;
1397	unsigned long flags;
1398	dma_addr_t buf;
1399	int head, tail;
1400
1401	/*
1402	 * DMA is idle now.
1403	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1404	 * offsets and lengths. Since it is a circular buffer, we have to
1405	 * transmit till the end, and then the rest. Take the port lock to get a
1406	 * consistent xmit buffer state.
1407	 */
1408	spin_lock_irq(&port->lock);
1409	head = xmit->head;
1410	tail = xmit->tail;
1411	buf = s->tx_dma_addr + (tail & (UART_XMIT_SIZE - 1));
1412	s->tx_dma_len = min_t(unsigned int,
1413		CIRC_CNT(head, tail, UART_XMIT_SIZE),
1414		CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE));
1415	if (!s->tx_dma_len) {
1416		/* Transmit buffer has been flushed */
1417		spin_unlock_irq(&port->lock);
1418		return;
1419	}
1420
1421	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1422					   DMA_MEM_TO_DEV,
1423					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1424	if (!desc) {
1425		spin_unlock_irq(&port->lock);
1426		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1427		goto switch_to_pio;
 
 
1428	}
1429
1430	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1431				   DMA_TO_DEVICE);
1432
 
1433	desc->callback = sci_dma_tx_complete;
1434	desc->callback_param = s;
 
1435	s->cookie_tx = dmaengine_submit(desc);
1436	if (dma_submit_error(s->cookie_tx)) {
1437		spin_unlock_irq(&port->lock);
1438		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1439		goto switch_to_pio;
 
 
1440	}
1441
1442	spin_unlock_irq(&port->lock);
1443	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1444		__func__, xmit->buf, tail, head, s->cookie_tx);
1445
1446	dma_async_issue_pending(chan);
1447	return;
1448
1449switch_to_pio:
1450	spin_lock_irqsave(&port->lock, flags);
1451	s->chan_tx = NULL;
1452	sci_start_tx(port);
1453	spin_unlock_irqrestore(&port->lock, flags);
1454	return;
1455}
1456
1457static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
1458{
1459	struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1460	struct dma_chan *chan = s->chan_rx;
1461	struct uart_port *port = &s->port;
1462	struct dma_tx_state state;
1463	enum dma_status status;
1464	unsigned long flags;
1465	unsigned int read;
1466	int active, count;
 
1467
1468	dev_dbg(port->dev, "DMA Rx timed out\n");
1469
1470	spin_lock_irqsave(&port->lock, flags);
1471
1472	active = sci_dma_rx_find_active(s);
1473	if (active < 0) {
1474		spin_unlock_irqrestore(&port->lock, flags);
1475		return HRTIMER_NORESTART;
1476	}
1477
1478	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1479	if (status == DMA_COMPLETE) {
1480		spin_unlock_irqrestore(&port->lock, flags);
1481		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1482			s->active_rx, active);
1483
1484		/* Let packet complete handler take care of the packet */
1485		return HRTIMER_NORESTART;
1486	}
1487
1488	dmaengine_pause(chan);
1489
1490	/*
1491	 * sometimes DMA transfer doesn't stop even if it is stopped and
1492	 * data keeps on coming until transaction is complete so check
1493	 * for DMA_COMPLETE again
1494	 * Let packet complete handler take care of the packet
1495	 */
1496	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1497	if (status == DMA_COMPLETE) {
1498		spin_unlock_irqrestore(&port->lock, flags);
1499		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1500		return HRTIMER_NORESTART;
1501	}
1502
1503	/* Handle incomplete DMA receive */
1504	dmaengine_terminate_async(s->chan_rx);
1505	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1506
1507	if (read) {
1508		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1509		if (count)
1510			tty_flip_buffer_push(&port->state->port);
1511	}
1512
1513	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1514		sci_dma_rx_submit(s, true);
1515
1516	sci_dma_rx_reenable_irq(s);
 
 
 
 
 
 
1517
1518	spin_unlock_irqrestore(&port->lock, flags);
1519
1520	return HRTIMER_NORESTART;
1521}
1522
1523static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1524					     enum dma_transfer_direction dir)
1525{
1526	struct dma_chan *chan;
1527	struct dma_slave_config cfg;
1528	int ret;
1529
1530	chan = dma_request_slave_channel(port->dev,
1531					 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1532	if (!chan) {
1533		dev_dbg(port->dev, "dma_request_slave_channel failed\n");
1534		return NULL;
1535	}
1536
1537	memset(&cfg, 0, sizeof(cfg));
1538	cfg.direction = dir;
1539	if (dir == DMA_MEM_TO_DEV) {
1540		cfg.dst_addr = port->mapbase +
1541			(sci_getreg(port, SCxTDR)->offset << port->regshift);
1542		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1543	} else {
1544		cfg.src_addr = port->mapbase +
1545			(sci_getreg(port, SCxRDR)->offset << port->regshift);
1546		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1547	}
1548
1549	ret = dmaengine_slave_config(chan, &cfg);
1550	if (ret) {
1551		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1552		dma_release_channel(chan);
1553		return NULL;
1554	}
1555
1556	return chan;
1557}
1558
1559static void sci_request_dma(struct uart_port *port)
1560{
1561	struct sci_port *s = to_sci_port(port);
1562	struct dma_chan *chan;
1563
1564	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1565
1566	/*
1567	 * DMA on console may interfere with Kernel log messages which use
1568	 * plain putchar(). So, simply don't use it with a console.
1569	 */
1570	if (uart_console(port))
1571		return;
1572
1573	if (!port->dev->of_node)
1574		return;
1575
1576	s->cookie_tx = -EINVAL;
1577
1578	/*
1579	 * Don't request a dma channel if no channel was specified
1580	 * in the device tree.
1581	 */
1582	if (!of_find_property(port->dev->of_node, "dmas", NULL))
1583		return;
1584
1585	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1586	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1587	if (chan) {
 
1588		/* UART circular tx buffer is an aligned page. */
1589		s->tx_dma_addr = dma_map_single(chan->device->dev,
1590						port->state->xmit.buf,
1591						UART_XMIT_SIZE,
1592						DMA_TO_DEVICE);
1593		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1594			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1595			dma_release_channel(chan);
 
1596		} else {
1597			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1598				__func__, UART_XMIT_SIZE,
1599				port->state->xmit.buf, &s->tx_dma_addr);
1600
1601			INIT_WORK(&s->work_tx, sci_dma_tx_work_fn);
1602			s->chan_tx_saved = s->chan_tx = chan;
1603		}
 
 
1604	}
1605
1606	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1607	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1608	if (chan) {
1609		unsigned int i;
1610		dma_addr_t dma;
1611		void *buf;
1612
 
 
1613		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1614		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1615					 &dma, GFP_KERNEL);
1616		if (!buf) {
1617			dev_warn(port->dev,
1618				 "Failed to allocate Rx dma buffer, using PIO\n");
1619			dma_release_channel(chan);
 
1620			return;
1621		}
1622
1623		for (i = 0; i < 2; i++) {
1624			struct scatterlist *sg = &s->sg_rx[i];
1625
1626			sg_init_table(sg, 1);
1627			s->rx_buf[i] = buf;
1628			sg_dma_address(sg) = dma;
1629			sg_dma_len(sg) = s->buf_len_rx;
1630
1631			buf += s->buf_len_rx;
1632			dma += s->buf_len_rx;
1633		}
1634
1635		hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1636		s->rx_timer.function = sci_dma_rx_timer_fn;
1637
1638		s->chan_rx_saved = s->chan_rx = chan;
1639
1640		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1641			sci_dma_rx_submit(s, false);
1642	}
1643}
1644
1645static void sci_free_dma(struct uart_port *port)
1646{
1647	struct sci_port *s = to_sci_port(port);
1648
1649	if (s->chan_tx_saved)
1650		sci_dma_tx_release(s);
1651	if (s->chan_rx_saved)
1652		sci_dma_rx_release(s);
1653}
1654
1655static void sci_flush_buffer(struct uart_port *port)
1656{
1657	struct sci_port *s = to_sci_port(port);
1658
1659	/*
1660	 * In uart_flush_buffer(), the xmit circular buffer has just been
1661	 * cleared, so we have to reset tx_dma_len accordingly, and stop any
1662	 * pending transfers
1663	 */
1664	s->tx_dma_len = 0;
1665	if (s->chan_tx) {
1666		dmaengine_terminate_async(s->chan_tx);
1667		s->cookie_tx = -EINVAL;
1668	}
1669}
1670#else /* !CONFIG_SERIAL_SH_SCI_DMA */
1671static inline void sci_request_dma(struct uart_port *port)
1672{
1673}
1674
1675static inline void sci_free_dma(struct uart_port *port)
1676{
1677}
1678
1679#define sci_flush_buffer	NULL
1680#endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1681
1682static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1683{
1684	struct uart_port *port = ptr;
1685	struct sci_port *s = to_sci_port(port);
1686
1687#ifdef CONFIG_SERIAL_SH_SCI_DMA
1688	if (s->chan_rx) {
1689		u16 scr = serial_port_in(port, SCSCR);
1690		u16 ssr = serial_port_in(port, SCxSR);
1691
1692		/* Disable future Rx interrupts */
1693		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1694			disable_irq_nosync(irq);
1695			scr |= SCSCR_RDRQE;
1696		} else {
1697			if (sci_dma_rx_submit(s, false) < 0)
1698				goto handle_pio;
1699
1700			scr &= ~SCSCR_RIE;
 
1701		}
1702		serial_port_out(port, SCSCR, scr);
1703		/* Clear current interrupt */
1704		serial_port_out(port, SCxSR,
1705				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1706		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1707			jiffies, s->rx_timeout);
1708		start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1709
1710		return IRQ_HANDLED;
1711	}
1712
1713handle_pio:
1714#endif
1715
1716	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1717		if (!scif_rtrg_enabled(port))
1718			scif_set_rtrg(port, s->rx_trigger);
1719
1720		mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1721			  s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1722	}
1723
1724	/* I think sci_receive_chars has to be called irrespective
1725	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1726	 * to be disabled?
1727	 */
1728	sci_receive_chars(port);
1729
1730	return IRQ_HANDLED;
1731}
1732
1733static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1734{
1735	struct uart_port *port = ptr;
1736	unsigned long flags;
1737
1738	spin_lock_irqsave(&port->lock, flags);
1739	sci_transmit_chars(port);
1740	spin_unlock_irqrestore(&port->lock, flags);
1741
1742	return IRQ_HANDLED;
1743}
1744
1745static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1746{
1747	struct uart_port *port = ptr;
1748
1749	/* Handle BREAKs */
1750	sci_handle_breaks(port);
1751	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1752
1753	return IRQ_HANDLED;
1754}
1755
1756static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1757{
1758	struct uart_port *port = ptr;
1759	struct sci_port *s = to_sci_port(port);
1760
1761	if (s->irqs[SCIx_ERI_IRQ] == s->irqs[SCIx_BRI_IRQ]) {
1762		/* Break and Error interrupts are muxed */
1763		unsigned short ssr_status = serial_port_in(port, SCxSR);
1764
1765		/* Break Interrupt */
1766		if (ssr_status & SCxSR_BRK(port))
1767			sci_br_interrupt(irq, ptr);
1768
1769		/* Break only? */
1770		if (!(ssr_status & SCxSR_ERRORS(port)))
1771			return IRQ_HANDLED;
1772	}
1773
1774	/* Handle errors */
1775	if (port->type == PORT_SCI) {
1776		if (sci_handle_errors(port)) {
1777			/* discard character in rx buffer */
1778			serial_port_in(port, SCxSR);
1779			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1780		}
1781	} else {
1782		sci_handle_fifo_overrun(port);
1783		if (!s->chan_rx)
1784			sci_receive_chars(port);
1785	}
1786
1787	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1788
1789	/* Kick the transmission */
1790	if (!s->chan_tx)
1791		sci_tx_interrupt(irq, ptr);
1792
1793	return IRQ_HANDLED;
1794}
1795
 
 
 
 
 
 
 
 
 
 
 
1796static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1797{
1798	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1799	struct uart_port *port = ptr;
1800	struct sci_port *s = to_sci_port(port);
1801	irqreturn_t ret = IRQ_NONE;
1802
1803	ssr_status = serial_port_in(port, SCxSR);
1804	scr_status = serial_port_in(port, SCSCR);
1805	if (s->params->overrun_reg == SCxSR)
1806		orer_status = ssr_status;
1807	else if (sci_getreg(port, s->params->overrun_reg)->size)
1808		orer_status = serial_port_in(port, s->params->overrun_reg);
1809
1810	err_enabled = scr_status & port_rx_irq_mask(port);
1811
1812	/* Tx Interrupt */
1813	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1814	    !s->chan_tx)
1815		ret = sci_tx_interrupt(irq, ptr);
1816
1817	/*
1818	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1819	 * DR flags
1820	 */
1821	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1822	    (scr_status & SCSCR_RIE))
1823		ret = sci_rx_interrupt(irq, ptr);
1824
1825	/* Error Interrupt */
1826	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1827		ret = sci_er_interrupt(irq, ptr);
1828
1829	/* Break Interrupt */
1830	if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1831		ret = sci_br_interrupt(irq, ptr);
1832
1833	/* Overrun Interrupt */
1834	if (orer_status & s->params->overrun_mask) {
1835		sci_handle_fifo_overrun(port);
1836		ret = IRQ_HANDLED;
1837	}
1838
1839	return ret;
1840}
1841
1842static const struct sci_irq_desc {
1843	const char	*desc;
1844	irq_handler_t	handler;
1845} sci_irq_desc[] = {
1846	/*
1847	 * Split out handlers, the default case.
1848	 */
1849	[SCIx_ERI_IRQ] = {
1850		.desc = "rx err",
1851		.handler = sci_er_interrupt,
1852	},
1853
1854	[SCIx_RXI_IRQ] = {
1855		.desc = "rx full",
1856		.handler = sci_rx_interrupt,
1857	},
1858
1859	[SCIx_TXI_IRQ] = {
1860		.desc = "tx empty",
1861		.handler = sci_tx_interrupt,
1862	},
1863
1864	[SCIx_BRI_IRQ] = {
1865		.desc = "break",
1866		.handler = sci_br_interrupt,
1867	},
1868
1869	[SCIx_DRI_IRQ] = {
1870		.desc = "rx ready",
1871		.handler = sci_rx_interrupt,
1872	},
1873
1874	[SCIx_TEI_IRQ] = {
1875		.desc = "tx end",
1876		.handler = sci_tx_interrupt,
1877	},
1878
1879	/*
1880	 * Special muxed handler.
1881	 */
1882	[SCIx_MUX_IRQ] = {
1883		.desc = "mux",
1884		.handler = sci_mpxed_interrupt,
1885	},
1886};
1887
1888static int sci_request_irq(struct sci_port *port)
1889{
1890	struct uart_port *up = &port->port;
1891	int i, j, w, ret = 0;
1892
1893	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1894		const struct sci_irq_desc *desc;
1895		int irq;
1896
1897		/* Check if already registered (muxed) */
1898		for (w = 0; w < i; w++)
1899			if (port->irqs[w] == port->irqs[i])
1900				w = i + 1;
1901		if (w > i)
1902			continue;
1903
1904		if (SCIx_IRQ_IS_MUXED(port)) {
1905			i = SCIx_MUX_IRQ;
1906			irq = up->irq;
1907		} else {
1908			irq = port->irqs[i];
1909
1910			/*
1911			 * Certain port types won't support all of the
1912			 * available interrupt sources.
1913			 */
1914			if (unlikely(irq < 0))
1915				continue;
1916		}
1917
1918		desc = sci_irq_desc + i;
1919		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1920					    dev_name(up->dev), desc->desc);
1921		if (!port->irqstr[j]) {
1922			ret = -ENOMEM;
1923			goto out_nomem;
1924		}
1925
1926		ret = request_irq(irq, desc->handler, up->irqflags,
1927				  port->irqstr[j], port);
1928		if (unlikely(ret)) {
1929			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1930			goto out_noirq;
1931		}
1932	}
1933
1934	return 0;
1935
1936out_noirq:
1937	while (--i >= 0)
1938		free_irq(port->irqs[i], port);
1939
1940out_nomem:
1941	while (--j >= 0)
1942		kfree(port->irqstr[j]);
1943
1944	return ret;
1945}
1946
1947static void sci_free_irq(struct sci_port *port)
1948{
1949	int i, j;
1950
1951	/*
1952	 * Intentionally in reverse order so we iterate over the muxed
1953	 * IRQ first.
1954	 */
1955	for (i = 0; i < SCIx_NR_IRQS; i++) {
1956		int irq = port->irqs[i];
1957
1958		/*
1959		 * Certain port types won't support all of the available
1960		 * interrupt sources.
1961		 */
1962		if (unlikely(irq < 0))
1963			continue;
1964
1965		/* Check if already freed (irq was muxed) */
1966		for (j = 0; j < i; j++)
1967			if (port->irqs[j] == irq)
1968				j = i + 1;
1969		if (j > i)
1970			continue;
1971
1972		free_irq(port->irqs[i], port);
1973		kfree(port->irqstr[i]);
1974
1975		if (SCIx_IRQ_IS_MUXED(port)) {
1976			/* If there's only one IRQ, we're done. */
1977			return;
1978		}
1979	}
1980}
1981
1982static unsigned int sci_tx_empty(struct uart_port *port)
1983{
1984	unsigned short status = serial_port_in(port, SCxSR);
1985	unsigned short in_tx_fifo = sci_txfill(port);
1986
1987	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1988}
1989
1990static void sci_set_rts(struct uart_port *port, bool state)
1991{
1992	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1993		u16 data = serial_port_in(port, SCPDR);
1994
1995		/* Active low */
1996		if (state)
1997			data &= ~SCPDR_RTSD;
1998		else
1999			data |= SCPDR_RTSD;
2000		serial_port_out(port, SCPDR, data);
2001
2002		/* RTS# is output */
2003		serial_port_out(port, SCPCR,
2004				serial_port_in(port, SCPCR) | SCPCR_RTSC);
2005	} else if (sci_getreg(port, SCSPTR)->size) {
2006		u16 ctrl = serial_port_in(port, SCSPTR);
2007
2008		/* Active low */
2009		if (state)
2010			ctrl &= ~SCSPTR_RTSDT;
2011		else
2012			ctrl |= SCSPTR_RTSDT;
2013		serial_port_out(port, SCSPTR, ctrl);
2014	}
2015}
2016
2017static bool sci_get_cts(struct uart_port *port)
2018{
2019	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2020		/* Active low */
2021		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
2022	} else if (sci_getreg(port, SCSPTR)->size) {
2023		/* Active low */
2024		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
2025	}
2026
2027	return true;
2028}
2029
2030/*
2031 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
2032 * CTS/RTS is supported in hardware by at least one port and controlled
2033 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
2034 * handled via the ->init_pins() op, which is a bit of a one-way street,
2035 * lacking any ability to defer pin control -- this will later be
2036 * converted over to the GPIO framework).
2037 *
2038 * Other modes (such as loopback) are supported generically on certain
2039 * port types, but not others. For these it's sufficient to test for the
2040 * existence of the support register and simply ignore the port type.
2041 */
2042static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
2043{
2044	struct sci_port *s = to_sci_port(port);
2045
2046	if (mctrl & TIOCM_LOOP) {
2047		const struct plat_sci_reg *reg;
2048
2049		/*
2050		 * Standard loopback mode for SCFCR ports.
2051		 */
2052		reg = sci_getreg(port, SCFCR);
2053		if (reg->size)
2054			serial_port_out(port, SCFCR,
2055					serial_port_in(port, SCFCR) |
2056					SCFCR_LOOP);
2057	}
2058
2059	mctrl_gpio_set(s->gpios, mctrl);
2060
2061	if (!s->has_rtscts)
2062		return;
2063
2064	if (!(mctrl & TIOCM_RTS)) {
2065		/* Disable Auto RTS */
2066		serial_port_out(port, SCFCR,
2067				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
2068
2069		/* Clear RTS */
2070		sci_set_rts(port, 0);
2071	} else if (s->autorts) {
2072		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2073			/* Enable RTS# pin function */
2074			serial_port_out(port, SCPCR,
2075				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
2076		}
2077
2078		/* Enable Auto RTS */
2079		serial_port_out(port, SCFCR,
2080				serial_port_in(port, SCFCR) | SCFCR_MCE);
2081	} else {
2082		/* Set RTS */
2083		sci_set_rts(port, 1);
2084	}
2085}
2086
2087static unsigned int sci_get_mctrl(struct uart_port *port)
2088{
2089	struct sci_port *s = to_sci_port(port);
2090	struct mctrl_gpios *gpios = s->gpios;
2091	unsigned int mctrl = 0;
2092
2093	mctrl_gpio_get(gpios, &mctrl);
2094
2095	/*
2096	 * CTS/RTS is handled in hardware when supported, while nothing
2097	 * else is wired up.
2098	 */
2099	if (s->autorts) {
2100		if (sci_get_cts(port))
2101			mctrl |= TIOCM_CTS;
2102	} else if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS)) {
2103		mctrl |= TIOCM_CTS;
2104	}
2105	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR))
2106		mctrl |= TIOCM_DSR;
2107	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD))
2108		mctrl |= TIOCM_CAR;
2109
2110	return mctrl;
2111}
2112
2113static void sci_enable_ms(struct uart_port *port)
2114{
2115	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2116}
2117
2118static void sci_break_ctl(struct uart_port *port, int break_state)
2119{
2120	unsigned short scscr, scsptr;
2121	unsigned long flags;
2122
2123	/* check wheter the port has SCSPTR */
2124	if (!sci_getreg(port, SCSPTR)->size) {
2125		/*
2126		 * Not supported by hardware. Most parts couple break and rx
2127		 * interrupts together, with break detection always enabled.
2128		 */
2129		return;
2130	}
2131
2132	spin_lock_irqsave(&port->lock, flags);
2133	scsptr = serial_port_in(port, SCSPTR);
2134	scscr = serial_port_in(port, SCSCR);
2135
2136	if (break_state == -1) {
2137		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2138		scscr &= ~SCSCR_TE;
2139	} else {
2140		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2141		scscr |= SCSCR_TE;
2142	}
2143
2144	serial_port_out(port, SCSPTR, scsptr);
2145	serial_port_out(port, SCSCR, scscr);
2146	spin_unlock_irqrestore(&port->lock, flags);
2147}
2148
2149static int sci_startup(struct uart_port *port)
2150{
2151	struct sci_port *s = to_sci_port(port);
2152	int ret;
2153
2154	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2155
2156	sci_request_dma(port);
2157
2158	ret = sci_request_irq(s);
2159	if (unlikely(ret < 0)) {
2160		sci_free_dma(port);
2161		return ret;
2162	}
2163
2164	return 0;
2165}
2166
2167static void sci_shutdown(struct uart_port *port)
2168{
2169	struct sci_port *s = to_sci_port(port);
2170	unsigned long flags;
2171	u16 scr;
2172
2173	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2174
2175	s->autorts = false;
2176	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2177
2178	spin_lock_irqsave(&port->lock, flags);
2179	sci_stop_rx(port);
2180	sci_stop_tx(port);
2181	/*
2182	 * Stop RX and TX, disable related interrupts, keep clock source
2183	 * and HSCIF TOT bits
2184	 */
2185	scr = serial_port_in(port, SCSCR);
2186	serial_port_out(port, SCSCR, scr &
2187			(SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2188	spin_unlock_irqrestore(&port->lock, flags);
2189
2190#ifdef CONFIG_SERIAL_SH_SCI_DMA
2191	if (s->chan_rx_saved) {
2192		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2193			port->line);
2194		hrtimer_cancel(&s->rx_timer);
2195	}
2196#endif
2197
2198	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
2199		del_timer_sync(&s->rx_fifo_timer);
2200	sci_free_irq(s);
2201	sci_free_dma(port);
2202}
2203
2204static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2205			unsigned int *srr)
2206{
2207	unsigned long freq = s->clk_rates[SCI_SCK];
2208	int err, min_err = INT_MAX;
2209	unsigned int sr;
2210
2211	if (s->port.type != PORT_HSCIF)
2212		freq *= 2;
2213
2214	for_each_sr(sr, s) {
2215		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2216		if (abs(err) >= abs(min_err))
2217			continue;
2218
2219		min_err = err;
2220		*srr = sr - 1;
2221
2222		if (!err)
2223			break;
2224	}
2225
2226	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2227		*srr + 1);
2228	return min_err;
2229}
2230
2231static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2232			unsigned long freq, unsigned int *dlr,
2233			unsigned int *srr)
2234{
2235	int err, min_err = INT_MAX;
2236	unsigned int sr, dl;
2237
2238	if (s->port.type != PORT_HSCIF)
2239		freq *= 2;
2240
2241	for_each_sr(sr, s) {
2242		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2243		dl = clamp(dl, 1U, 65535U);
2244
2245		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2246		if (abs(err) >= abs(min_err))
2247			continue;
2248
2249		min_err = err;
2250		*dlr = dl;
2251		*srr = sr - 1;
2252
2253		if (!err)
2254			break;
2255	}
2256
2257	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2258		min_err, *dlr, *srr + 1);
2259	return min_err;
2260}
2261
2262/* calculate sample rate, BRR, and clock select */
2263static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2264			  unsigned int *brr, unsigned int *srr,
2265			  unsigned int *cks)
2266{
2267	unsigned long freq = s->clk_rates[SCI_FCK];
2268	unsigned int sr, br, prediv, scrate, c;
2269	int err, min_err = INT_MAX;
2270
2271	if (s->port.type != PORT_HSCIF)
2272		freq *= 2;
2273
2274	/*
2275	 * Find the combination of sample rate and clock select with the
2276	 * smallest deviation from the desired baud rate.
2277	 * Prefer high sample rates to maximise the receive margin.
2278	 *
2279	 * M: Receive margin (%)
2280	 * N: Ratio of bit rate to clock (N = sampling rate)
2281	 * D: Clock duty (D = 0 to 1.0)
2282	 * L: Frame length (L = 9 to 12)
2283	 * F: Absolute value of clock frequency deviation
2284	 *
2285	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2286	 *      (|D - 0.5| / N * (1 + F))|
2287	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2288	 */
2289	for_each_sr(sr, s) {
2290		for (c = 0; c <= 3; c++) {
2291			/* integerized formulas from HSCIF documentation */
2292			prediv = sr * (1 << (2 * c + 1));
2293
2294			/*
2295			 * We need to calculate:
2296			 *
2297			 *     br = freq / (prediv * bps) clamped to [1..256]
2298			 *     err = freq / (br * prediv) - bps
2299			 *
2300			 * Watch out for overflow when calculating the desired
2301			 * sampling clock rate!
2302			 */
2303			if (bps > UINT_MAX / prediv)
2304				break;
2305
2306			scrate = prediv * bps;
2307			br = DIV_ROUND_CLOSEST(freq, scrate);
2308			br = clamp(br, 1U, 256U);
2309
2310			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2311			if (abs(err) >= abs(min_err))
2312				continue;
2313
2314			min_err = err;
2315			*brr = br - 1;
2316			*srr = sr - 1;
2317			*cks = c;
2318
2319			if (!err)
2320				goto found;
2321		}
2322	}
2323
2324found:
2325	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2326		min_err, *brr, *srr + 1, *cks);
2327	return min_err;
2328}
2329
2330static void sci_reset(struct uart_port *port)
2331{
2332	const struct plat_sci_reg *reg;
2333	unsigned int status;
2334	struct sci_port *s = to_sci_port(port);
2335
2336	serial_port_out(port, SCSCR, s->hscif_tot);	/* TE=0, RE=0, CKE1=0 */
2337
2338	reg = sci_getreg(port, SCFCR);
2339	if (reg->size)
2340		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2341
2342	sci_clear_SCxSR(port,
2343			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2344			SCxSR_BREAK_CLEAR(port));
2345	if (sci_getreg(port, SCLSR)->size) {
2346		status = serial_port_in(port, SCLSR);
2347		status &= ~(SCLSR_TO | SCLSR_ORER);
2348		serial_port_out(port, SCLSR, status);
2349	}
2350
2351	if (s->rx_trigger > 1) {
2352		if (s->rx_fifo_timeout) {
2353			scif_set_rtrg(port, 1);
2354			timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2355		} else {
2356			if (port->type == PORT_SCIFA ||
2357			    port->type == PORT_SCIFB)
2358				scif_set_rtrg(port, 1);
2359			else
2360				scif_set_rtrg(port, s->rx_trigger);
2361		}
2362	}
2363}
2364
2365static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2366			    struct ktermios *old)
2367{
2368	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2369	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2370	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2371	struct sci_port *s = to_sci_port(port);
2372	const struct plat_sci_reg *reg;
2373	int min_err = INT_MAX, err;
2374	unsigned long max_freq = 0;
2375	int best_clk = -1;
2376	unsigned long flags;
2377
2378	if ((termios->c_cflag & CSIZE) == CS7)
2379		smr_val |= SCSMR_CHR;
2380	if (termios->c_cflag & PARENB)
2381		smr_val |= SCSMR_PE;
2382	if (termios->c_cflag & PARODD)
2383		smr_val |= SCSMR_PE | SCSMR_ODD;
2384	if (termios->c_cflag & CSTOPB)
2385		smr_val |= SCSMR_STOP;
2386
2387	/*
2388	 * earlyprintk comes here early on with port->uartclk set to zero.
2389	 * the clock framework is not up and running at this point so here
2390	 * we assume that 115200 is the maximum baud rate. please note that
2391	 * the baud rate is not programmed during earlyprintk - it is assumed
2392	 * that the previous boot loader has enabled required clocks and
2393	 * setup the baud rate generator hardware for us already.
2394	 */
2395	if (!port->uartclk) {
2396		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2397		goto done;
2398	}
2399
2400	for (i = 0; i < SCI_NUM_CLKS; i++)
2401		max_freq = max(max_freq, s->clk_rates[i]);
2402
2403	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2404	if (!baud)
2405		goto done;
2406
2407	/*
2408	 * There can be multiple sources for the sampling clock.  Find the one
2409	 * that gives us the smallest deviation from the desired baud rate.
2410	 */
2411
2412	/* Optional Undivided External Clock */
2413	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2414	    port->type != PORT_SCIFB) {
2415		err = sci_sck_calc(s, baud, &srr1);
2416		if (abs(err) < abs(min_err)) {
2417			best_clk = SCI_SCK;
2418			scr_val = SCSCR_CKE1;
2419			sccks = SCCKS_CKS;
2420			min_err = err;
2421			srr = srr1;
2422			if (!err)
2423				goto done;
2424		}
2425	}
2426
2427	/* Optional BRG Frequency Divided External Clock */
2428	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2429		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2430				   &srr1);
2431		if (abs(err) < abs(min_err)) {
2432			best_clk = SCI_SCIF_CLK;
2433			scr_val = SCSCR_CKE1;
2434			sccks = 0;
2435			min_err = err;
2436			dl = dl1;
2437			srr = srr1;
2438			if (!err)
2439				goto done;
2440		}
2441	}
2442
2443	/* Optional BRG Frequency Divided Internal Clock */
2444	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2445		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2446				   &srr1);
2447		if (abs(err) < abs(min_err)) {
2448			best_clk = SCI_BRG_INT;
2449			scr_val = SCSCR_CKE1;
2450			sccks = SCCKS_XIN;
2451			min_err = err;
2452			dl = dl1;
2453			srr = srr1;
2454			if (!min_err)
2455				goto done;
2456		}
2457	}
2458
2459	/* Divided Functional Clock using standard Bit Rate Register */
2460	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2461	if (abs(err) < abs(min_err)) {
2462		best_clk = SCI_FCK;
2463		scr_val = 0;
2464		min_err = err;
2465		brr = brr1;
2466		srr = srr1;
2467		cks = cks1;
2468	}
2469
2470done:
2471	if (best_clk >= 0)
2472		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2473			s->clks[best_clk], baud, min_err);
2474
2475	sci_port_enable(s);
2476
2477	/*
2478	 * Program the optional External Baud Rate Generator (BRG) first.
2479	 * It controls the mux to select (H)SCK or frequency divided clock.
2480	 */
2481	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2482		serial_port_out(port, SCDL, dl);
2483		serial_port_out(port, SCCKS, sccks);
2484	}
2485
2486	spin_lock_irqsave(&port->lock, flags);
2487
2488	sci_reset(port);
2489
2490	uart_update_timeout(port, termios->c_cflag, baud);
2491
2492	/* byte size and parity */
2493	switch (termios->c_cflag & CSIZE) {
2494	case CS5:
2495		bits = 7;
2496		break;
2497	case CS6:
2498		bits = 8;
2499		break;
2500	case CS7:
2501		bits = 9;
2502		break;
2503	default:
2504		bits = 10;
2505		break;
2506	}
2507
2508	if (termios->c_cflag & CSTOPB)
2509		bits++;
2510	if (termios->c_cflag & PARENB)
2511		bits++;
2512
2513	if (best_clk >= 0) {
2514		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2515			switch (srr + 1) {
2516			case 5:  smr_val |= SCSMR_SRC_5;  break;
2517			case 7:  smr_val |= SCSMR_SRC_7;  break;
2518			case 11: smr_val |= SCSMR_SRC_11; break;
2519			case 13: smr_val |= SCSMR_SRC_13; break;
2520			case 16: smr_val |= SCSMR_SRC_16; break;
2521			case 17: smr_val |= SCSMR_SRC_17; break;
2522			case 19: smr_val |= SCSMR_SRC_19; break;
2523			case 27: smr_val |= SCSMR_SRC_27; break;
2524			}
2525		smr_val |= cks;
2526		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2527		serial_port_out(port, SCSMR, smr_val);
2528		serial_port_out(port, SCBRR, brr);
2529		if (sci_getreg(port, HSSRR)->size) {
2530			unsigned int hssrr = srr | HSCIF_SRE;
2531			/* Calculate deviation from intended rate at the
2532			 * center of the last stop bit in sampling clocks.
2533			 */
2534			int last_stop = bits * 2 - 1;
2535			int deviation = DIV_ROUND_CLOSEST(min_err * last_stop *
2536							  (int)(srr + 1),
2537							  2 * (int)baud);
2538
2539			if (abs(deviation) >= 2) {
2540				/* At least two sampling clocks off at the
2541				 * last stop bit; we can increase the error
2542				 * margin by shifting the sampling point.
2543				 */
2544				int shift = clamp(deviation / 2, -8, 7);
2545
2546				hssrr |= (shift << HSCIF_SRHP_SHIFT) &
2547					 HSCIF_SRHP_MASK;
2548				hssrr |= HSCIF_SRDE;
2549			}
2550			serial_port_out(port, HSSRR, hssrr);
2551		}
2552
2553		/* Wait one bit interval */
2554		udelay((1000000 + (baud - 1)) / baud);
2555	} else {
2556		/* Don't touch the bit rate configuration */
2557		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2558		smr_val |= serial_port_in(port, SCSMR) &
2559			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2560		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2561		serial_port_out(port, SCSMR, smr_val);
2562	}
2563
2564	sci_init_pins(port, termios->c_cflag);
2565
2566	port->status &= ~UPSTAT_AUTOCTS;
2567	s->autorts = false;
2568	reg = sci_getreg(port, SCFCR);
2569	if (reg->size) {
2570		unsigned short ctrl = serial_port_in(port, SCFCR);
2571
2572		if ((port->flags & UPF_HARD_FLOW) &&
2573		    (termios->c_cflag & CRTSCTS)) {
2574			/* There is no CTS interrupt to restart the hardware */
2575			port->status |= UPSTAT_AUTOCTS;
2576			/* MCE is enabled when RTS is raised */
2577			s->autorts = true;
2578		}
2579
2580		/*
2581		 * As we've done a sci_reset() above, ensure we don't
2582		 * interfere with the FIFOs while toggling MCE. As the
2583		 * reset values could still be set, simply mask them out.
2584		 */
2585		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2586
2587		serial_port_out(port, SCFCR, ctrl);
2588	}
2589	if (port->flags & UPF_HARD_FLOW) {
2590		/* Refresh (Auto) RTS */
2591		sci_set_mctrl(port, port->mctrl);
2592	}
2593
2594	scr_val |= SCSCR_RE | SCSCR_TE |
2595		   (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2596	serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2597	if ((srr + 1 == 5) &&
2598	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2599		/*
2600		 * In asynchronous mode, when the sampling rate is 1/5, first
2601		 * received data may become invalid on some SCIFA and SCIFB.
2602		 * To avoid this problem wait more than 1 serial data time (1
2603		 * bit time x serial data number) after setting SCSCR.RE = 1.
2604		 */
2605		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2606	}
2607
2608	/*
2609	 * Calculate delay for 2 DMA buffers (4 FIFO).
2610	 * See serial_core.c::uart_update_timeout().
2611	 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2612	 * function calculates 1 jiffie for the data plus 5 jiffies for the
2613	 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2614	 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2615	 * value obtained by this formula is too small. Therefore, if the value
2616	 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2617	 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2618	s->rx_frame = (10000 * bits) / (baud / 100);
2619#ifdef CONFIG_SERIAL_SH_SCI_DMA
2620	s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2621	if (s->rx_timeout < 20)
2622		s->rx_timeout = 20;
2623#endif
2624
2625	if ((termios->c_cflag & CREAD) != 0)
2626		sci_start_rx(port);
2627
2628	spin_unlock_irqrestore(&port->lock, flags);
2629
2630	sci_port_disable(s);
2631
2632	if (UART_ENABLE_MS(port, termios->c_cflag))
2633		sci_enable_ms(port);
2634}
2635
2636static void sci_pm(struct uart_port *port, unsigned int state,
2637		   unsigned int oldstate)
2638{
2639	struct sci_port *sci_port = to_sci_port(port);
2640
2641	switch (state) {
2642	case UART_PM_STATE_OFF:
2643		sci_port_disable(sci_port);
2644		break;
2645	default:
2646		sci_port_enable(sci_port);
2647		break;
2648	}
2649}
2650
2651static const char *sci_type(struct uart_port *port)
2652{
2653	switch (port->type) {
2654	case PORT_IRDA:
2655		return "irda";
2656	case PORT_SCI:
2657		return "sci";
2658	case PORT_SCIF:
2659		return "scif";
2660	case PORT_SCIFA:
2661		return "scifa";
2662	case PORT_SCIFB:
2663		return "scifb";
2664	case PORT_HSCIF:
2665		return "hscif";
2666	}
2667
2668	return NULL;
2669}
2670
2671static int sci_remap_port(struct uart_port *port)
2672{
2673	struct sci_port *sport = to_sci_port(port);
2674
2675	/*
2676	 * Nothing to do if there's already an established membase.
2677	 */
2678	if (port->membase)
2679		return 0;
2680
2681	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2682		port->membase = ioremap_nocache(port->mapbase, sport->reg_size);
2683		if (unlikely(!port->membase)) {
2684			dev_err(port->dev, "can't remap port#%d\n", port->line);
2685			return -ENXIO;
2686		}
2687	} else {
2688		/*
2689		 * For the simple (and majority of) cases where we don't
2690		 * need to do any remapping, just cast the cookie
2691		 * directly.
2692		 */
2693		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2694	}
2695
2696	return 0;
2697}
2698
2699static void sci_release_port(struct uart_port *port)
2700{
2701	struct sci_port *sport = to_sci_port(port);
2702
2703	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2704		iounmap(port->membase);
2705		port->membase = NULL;
2706	}
2707
2708	release_mem_region(port->mapbase, sport->reg_size);
2709}
2710
2711static int sci_request_port(struct uart_port *port)
2712{
2713	struct resource *res;
2714	struct sci_port *sport = to_sci_port(port);
2715	int ret;
2716
2717	res = request_mem_region(port->mapbase, sport->reg_size,
2718				 dev_name(port->dev));
2719	if (unlikely(res == NULL)) {
2720		dev_err(port->dev, "request_mem_region failed.");
2721		return -EBUSY;
2722	}
2723
2724	ret = sci_remap_port(port);
2725	if (unlikely(ret != 0)) {
2726		release_resource(res);
2727		return ret;
2728	}
2729
2730	return 0;
2731}
2732
2733static void sci_config_port(struct uart_port *port, int flags)
2734{
2735	if (flags & UART_CONFIG_TYPE) {
2736		struct sci_port *sport = to_sci_port(port);
2737
2738		port->type = sport->cfg->type;
2739		sci_request_port(port);
2740	}
2741}
2742
2743static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2744{
2745	if (ser->baud_base < 2400)
2746		/* No paper tape reader for Mitch.. */
2747		return -EINVAL;
2748
2749	return 0;
2750}
2751
2752static const struct uart_ops sci_uart_ops = {
2753	.tx_empty	= sci_tx_empty,
2754	.set_mctrl	= sci_set_mctrl,
2755	.get_mctrl	= sci_get_mctrl,
2756	.start_tx	= sci_start_tx,
2757	.stop_tx	= sci_stop_tx,
2758	.stop_rx	= sci_stop_rx,
2759	.enable_ms	= sci_enable_ms,
2760	.break_ctl	= sci_break_ctl,
2761	.startup	= sci_startup,
2762	.shutdown	= sci_shutdown,
2763	.flush_buffer	= sci_flush_buffer,
2764	.set_termios	= sci_set_termios,
2765	.pm		= sci_pm,
2766	.type		= sci_type,
2767	.release_port	= sci_release_port,
2768	.request_port	= sci_request_port,
2769	.config_port	= sci_config_port,
2770	.verify_port	= sci_verify_port,
2771#ifdef CONFIG_CONSOLE_POLL
2772	.poll_get_char	= sci_poll_get_char,
2773	.poll_put_char	= sci_poll_put_char,
2774#endif
2775};
2776
2777static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2778{
2779	const char *clk_names[] = {
2780		[SCI_FCK] = "fck",
2781		[SCI_SCK] = "sck",
2782		[SCI_BRG_INT] = "brg_int",
2783		[SCI_SCIF_CLK] = "scif_clk",
2784	};
2785	struct clk *clk;
2786	unsigned int i;
2787
2788	if (sci_port->cfg->type == PORT_HSCIF)
2789		clk_names[SCI_SCK] = "hsck";
2790
2791	for (i = 0; i < SCI_NUM_CLKS; i++) {
2792		clk = devm_clk_get(dev, clk_names[i]);
2793		if (PTR_ERR(clk) == -EPROBE_DEFER)
2794			return -EPROBE_DEFER;
2795
2796		if (IS_ERR(clk) && i == SCI_FCK) {
2797			/*
2798			 * "fck" used to be called "sci_ick", and we need to
2799			 * maintain DT backward compatibility.
2800			 */
2801			clk = devm_clk_get(dev, "sci_ick");
2802			if (PTR_ERR(clk) == -EPROBE_DEFER)
2803				return -EPROBE_DEFER;
2804
2805			if (!IS_ERR(clk))
2806				goto found;
2807
2808			/*
2809			 * Not all SH platforms declare a clock lookup entry
2810			 * for SCI devices, in which case we need to get the
2811			 * global "peripheral_clk" clock.
2812			 */
2813			clk = devm_clk_get(dev, "peripheral_clk");
2814			if (!IS_ERR(clk))
2815				goto found;
2816
2817			dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2818				PTR_ERR(clk));
2819			return PTR_ERR(clk);
2820		}
2821
2822found:
2823		if (IS_ERR(clk))
2824			dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2825				PTR_ERR(clk));
2826		else
2827			dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
2828				clk, clk_get_rate(clk));
2829		sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2830	}
2831	return 0;
2832}
2833
2834static const struct sci_port_params *
2835sci_probe_regmap(const struct plat_sci_port *cfg)
2836{
2837	unsigned int regtype;
2838
2839	if (cfg->regtype != SCIx_PROBE_REGTYPE)
2840		return &sci_port_params[cfg->regtype];
2841
2842	switch (cfg->type) {
2843	case PORT_SCI:
2844		regtype = SCIx_SCI_REGTYPE;
2845		break;
2846	case PORT_IRDA:
2847		regtype = SCIx_IRDA_REGTYPE;
2848		break;
2849	case PORT_SCIFA:
2850		regtype = SCIx_SCIFA_REGTYPE;
2851		break;
2852	case PORT_SCIFB:
2853		regtype = SCIx_SCIFB_REGTYPE;
2854		break;
2855	case PORT_SCIF:
2856		/*
2857		 * The SH-4 is a bit of a misnomer here, although that's
2858		 * where this particular port layout originated. This
2859		 * configuration (or some slight variation thereof)
2860		 * remains the dominant model for all SCIFs.
2861		 */
2862		regtype = SCIx_SH4_SCIF_REGTYPE;
2863		break;
2864	case PORT_HSCIF:
2865		regtype = SCIx_HSCIF_REGTYPE;
2866		break;
2867	default:
2868		pr_err("Can't probe register map for given port\n");
2869		return NULL;
2870	}
2871
2872	return &sci_port_params[regtype];
2873}
2874
2875static int sci_init_single(struct platform_device *dev,
2876			   struct sci_port *sci_port, unsigned int index,
2877			   const struct plat_sci_port *p, bool early)
2878{
2879	struct uart_port *port = &sci_port->port;
2880	const struct resource *res;
2881	unsigned int i;
2882	int ret;
2883
2884	sci_port->cfg	= p;
2885
2886	port->ops	= &sci_uart_ops;
2887	port->iotype	= UPIO_MEM;
2888	port->line	= index;
2889
2890	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2891	if (res == NULL)
2892		return -ENOMEM;
2893
2894	port->mapbase = res->start;
2895	sci_port->reg_size = resource_size(res);
2896
2897	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) {
2898		if (i)
2899			sci_port->irqs[i] = platform_get_irq_optional(dev, i);
2900		else
2901			sci_port->irqs[i] = platform_get_irq(dev, i);
2902	}
2903
2904	/* The SCI generates several interrupts. They can be muxed together or
2905	 * connected to different interrupt lines. In the muxed case only one
2906	 * interrupt resource is specified as there is only one interrupt ID.
2907	 * In the non-muxed case, up to 6 interrupt signals might be generated
2908	 * from the SCI, however those signals might have their own individual
2909	 * interrupt ID numbers, or muxed together with another interrupt.
2910	 */
2911	if (sci_port->irqs[0] < 0)
2912		return -ENXIO;
2913
2914	if (sci_port->irqs[1] < 0)
2915		for (i = 1; i < ARRAY_SIZE(sci_port->irqs); i++)
2916			sci_port->irqs[i] = sci_port->irqs[0];
 
 
2917
2918	sci_port->params = sci_probe_regmap(p);
2919	if (unlikely(sci_port->params == NULL))
2920		return -EINVAL;
2921
2922	switch (p->type) {
2923	case PORT_SCIFB:
2924		sci_port->rx_trigger = 48;
2925		break;
2926	case PORT_HSCIF:
2927		sci_port->rx_trigger = 64;
2928		break;
2929	case PORT_SCIFA:
2930		sci_port->rx_trigger = 32;
2931		break;
2932	case PORT_SCIF:
2933		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2934			/* RX triggering not implemented for this IP */
2935			sci_port->rx_trigger = 1;
2936		else
2937			sci_port->rx_trigger = 8;
2938		break;
2939	default:
2940		sci_port->rx_trigger = 1;
2941		break;
2942	}
2943
2944	sci_port->rx_fifo_timeout = 0;
2945	sci_port->hscif_tot = 0;
2946
2947	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2948	 * match the SoC datasheet, this should be investigated. Let platform
2949	 * data override the sampling rate for now.
2950	 */
2951	sci_port->sampling_rate_mask = p->sampling_rate
2952				     ? SCI_SR(p->sampling_rate)
2953				     : sci_port->params->sampling_rate_mask;
2954
2955	if (!early) {
2956		ret = sci_init_clocks(sci_port, &dev->dev);
2957		if (ret < 0)
2958			return ret;
2959
2960		port->dev = &dev->dev;
2961
2962		pm_runtime_enable(&dev->dev);
2963	}
2964
2965	port->type		= p->type;
2966	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2967	port->fifosize		= sci_port->params->fifosize;
2968
2969	if (port->type == PORT_SCI) {
2970		if (sci_port->reg_size >= 0x20)
2971			port->regshift = 2;
2972		else
2973			port->regshift = 1;
2974	}
2975
2976	/*
2977	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2978	 * for the multi-IRQ ports, which is where we are primarily
2979	 * concerned with the shutdown path synchronization.
2980	 *
2981	 * For the muxed case there's nothing more to do.
2982	 */
2983	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
2984	port->irqflags		= 0;
2985
2986	port->serial_in		= sci_serial_in;
2987	port->serial_out	= sci_serial_out;
2988
2989	return 0;
2990}
2991
2992static void sci_cleanup_single(struct sci_port *port)
2993{
2994	pm_runtime_disable(port->port.dev);
2995}
2996
2997#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2998    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2999static void serial_console_putchar(struct uart_port *port, int ch)
3000{
3001	sci_poll_put_char(port, ch);
3002}
3003
3004/*
3005 *	Print a string to the serial port trying not to disturb
3006 *	any possible real use of the port...
3007 */
3008static void serial_console_write(struct console *co, const char *s,
3009				 unsigned count)
3010{
3011	struct sci_port *sci_port = &sci_ports[co->index];
3012	struct uart_port *port = &sci_port->port;
3013	unsigned short bits, ctrl, ctrl_temp;
3014	unsigned long flags;
3015	int locked = 1;
3016
 
3017#if defined(SUPPORT_SYSRQ)
3018	if (port->sysrq)
3019		locked = 0;
3020	else
3021#endif
3022	if (oops_in_progress)
3023		locked = spin_trylock_irqsave(&port->lock, flags);
3024	else
3025		spin_lock_irqsave(&port->lock, flags);
3026
3027	/* first save SCSCR then disable interrupts, keep clock source */
3028	ctrl = serial_port_in(port, SCSCR);
3029	ctrl_temp = SCSCR_RE | SCSCR_TE |
3030		    (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
3031		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
3032	serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
3033
3034	uart_console_write(port, s, count, serial_console_putchar);
3035
3036	/* wait until fifo is empty and last bit has been transmitted */
3037	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
3038	while ((serial_port_in(port, SCxSR) & bits) != bits)
3039		cpu_relax();
3040
3041	/* restore the SCSCR */
3042	serial_port_out(port, SCSCR, ctrl);
3043
3044	if (locked)
3045		spin_unlock_irqrestore(&port->lock, flags);
 
3046}
3047
3048static int serial_console_setup(struct console *co, char *options)
3049{
3050	struct sci_port *sci_port;
3051	struct uart_port *port;
3052	int baud = 115200;
3053	int bits = 8;
3054	int parity = 'n';
3055	int flow = 'n';
3056	int ret;
3057
3058	/*
3059	 * Refuse to handle any bogus ports.
3060	 */
3061	if (co->index < 0 || co->index >= SCI_NPORTS)
3062		return -ENODEV;
3063
3064	sci_port = &sci_ports[co->index];
3065	port = &sci_port->port;
3066
3067	/*
3068	 * Refuse to handle uninitialized ports.
3069	 */
3070	if (!port->ops)
3071		return -ENODEV;
3072
3073	ret = sci_remap_port(port);
3074	if (unlikely(ret != 0))
3075		return ret;
3076
3077	if (options)
3078		uart_parse_options(options, &baud, &parity, &bits, &flow);
3079
3080	return uart_set_options(port, co, baud, parity, bits, flow);
3081}
3082
3083static struct console serial_console = {
3084	.name		= "ttySC",
3085	.device		= uart_console_device,
3086	.write		= serial_console_write,
3087	.setup		= serial_console_setup,
3088	.flags		= CON_PRINTBUFFER,
3089	.index		= -1,
3090	.data		= &sci_uart_driver,
3091};
3092
3093static struct console early_serial_console = {
3094	.name           = "early_ttySC",
3095	.write          = serial_console_write,
3096	.flags          = CON_PRINTBUFFER,
3097	.index		= -1,
3098};
3099
3100static char early_serial_buf[32];
3101
3102static int sci_probe_earlyprintk(struct platform_device *pdev)
3103{
3104	const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
3105
3106	if (early_serial_console.data)
3107		return -EEXIST;
3108
3109	early_serial_console.index = pdev->id;
3110
3111	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
3112
3113	serial_console_setup(&early_serial_console, early_serial_buf);
3114
3115	if (!strstr(early_serial_buf, "keep"))
3116		early_serial_console.flags |= CON_BOOT;
3117
3118	register_console(&early_serial_console);
3119	return 0;
3120}
3121
3122#define SCI_CONSOLE	(&serial_console)
3123
3124#else
3125static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3126{
3127	return -EINVAL;
3128}
3129
3130#define SCI_CONSOLE	NULL
3131
3132#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3133
3134static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3135
3136static DEFINE_MUTEX(sci_uart_registration_lock);
3137static struct uart_driver sci_uart_driver = {
3138	.owner		= THIS_MODULE,
3139	.driver_name	= "sci",
3140	.dev_name	= "ttySC",
3141	.major		= SCI_MAJOR,
3142	.minor		= SCI_MINOR_START,
3143	.nr		= SCI_NPORTS,
3144	.cons		= SCI_CONSOLE,
3145};
3146
3147static int sci_remove(struct platform_device *dev)
3148{
3149	struct sci_port *port = platform_get_drvdata(dev);
3150	unsigned int type = port->port.type;	/* uart_remove_... clears it */
3151
3152	sci_ports_in_use &= ~BIT(port->port.line);
3153	uart_remove_one_port(&sci_uart_driver, &port->port);
3154
3155	sci_cleanup_single(port);
3156
3157	if (port->port.fifosize > 1)
3158		device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3159	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
3160		device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
 
 
 
 
 
3161
3162	return 0;
3163}
3164
3165
3166#define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
3167#define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
3168#define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
3169
3170static const struct of_device_id of_sci_match[] = {
3171	/* SoC-specific types */
3172	{
3173		.compatible = "renesas,scif-r7s72100",
3174		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3175	},
3176	{
3177		.compatible = "renesas,scif-r7s9210",
3178		.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3179	},
3180	/* Family-specific types */
3181	{
3182		.compatible = "renesas,rcar-gen1-scif",
3183		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3184	}, {
3185		.compatible = "renesas,rcar-gen2-scif",
3186		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3187	}, {
3188		.compatible = "renesas,rcar-gen3-scif",
3189		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3190	},
3191	/* Generic types */
3192	{
3193		.compatible = "renesas,scif",
3194		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3195	}, {
3196		.compatible = "renesas,scifa",
3197		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3198	}, {
3199		.compatible = "renesas,scifb",
3200		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3201	}, {
3202		.compatible = "renesas,hscif",
3203		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3204	}, {
3205		.compatible = "renesas,sci",
3206		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3207	}, {
3208		/* Terminator */
3209	},
3210};
3211MODULE_DEVICE_TABLE(of, of_sci_match);
3212
3213static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3214					  unsigned int *dev_id)
3215{
3216	struct device_node *np = pdev->dev.of_node;
3217	struct plat_sci_port *p;
3218	struct sci_port *sp;
3219	const void *data;
3220	int id;
3221
3222	if (!IS_ENABLED(CONFIG_OF) || !np)
3223		return NULL;
3224
3225	data = of_device_get_match_data(&pdev->dev);
3226
3227	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3228	if (!p)
3229		return NULL;
3230
3231	/* Get the line number from the aliases node. */
3232	id = of_alias_get_id(np, "serial");
3233	if (id < 0 && ~sci_ports_in_use)
3234		id = ffz(sci_ports_in_use);
3235	if (id < 0) {
3236		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3237		return NULL;
3238	}
3239	if (id >= ARRAY_SIZE(sci_ports)) {
3240		dev_err(&pdev->dev, "serial%d out of range\n", id);
3241		return NULL;
3242	}
3243
3244	sp = &sci_ports[id];
3245	*dev_id = id;
3246
3247	p->type = SCI_OF_TYPE(data);
3248	p->regtype = SCI_OF_REGTYPE(data);
3249
3250	sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3251
3252	return p;
3253}
3254
3255static int sci_probe_single(struct platform_device *dev,
3256				      unsigned int index,
3257				      struct plat_sci_port *p,
3258				      struct sci_port *sciport)
3259{
3260	int ret;
3261
3262	/* Sanity check */
3263	if (unlikely(index >= SCI_NPORTS)) {
3264		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3265			   index+1, SCI_NPORTS);
3266		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3267		return -EINVAL;
3268	}
3269	BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
3270	if (sci_ports_in_use & BIT(index))
3271		return -EBUSY;
3272
3273	mutex_lock(&sci_uart_registration_lock);
3274	if (!sci_uart_driver.state) {
3275		ret = uart_register_driver(&sci_uart_driver);
3276		if (ret) {
3277			mutex_unlock(&sci_uart_registration_lock);
3278			return ret;
3279		}
3280	}
3281	mutex_unlock(&sci_uart_registration_lock);
3282
3283	ret = sci_init_single(dev, sciport, index, p, false);
3284	if (ret)
3285		return ret;
3286
3287	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3288	if (IS_ERR(sciport->gpios))
3289		return PTR_ERR(sciport->gpios);
3290
3291	if (sciport->has_rtscts) {
3292		if (mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_CTS) ||
3293		    mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_RTS)) {
 
 
3294			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3295			return -EINVAL;
3296		}
3297		sciport->port.flags |= UPF_HARD_FLOW;
3298	}
3299
3300	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3301	if (ret) {
3302		sci_cleanup_single(sciport);
3303		return ret;
3304	}
3305
3306	return 0;
3307}
3308
3309static int sci_probe(struct platform_device *dev)
3310{
3311	struct plat_sci_port *p;
3312	struct sci_port *sp;
3313	unsigned int dev_id;
3314	int ret;
3315
3316	/*
3317	 * If we've come here via earlyprintk initialization, head off to
3318	 * the special early probe. We don't have sufficient device state
3319	 * to make it beyond this yet.
3320	 */
3321	if (is_early_platform_device(dev))
3322		return sci_probe_earlyprintk(dev);
3323
3324	if (dev->dev.of_node) {
3325		p = sci_parse_dt(dev, &dev_id);
3326		if (p == NULL)
3327			return -EINVAL;
3328	} else {
3329		p = dev->dev.platform_data;
3330		if (p == NULL) {
3331			dev_err(&dev->dev, "no platform data supplied\n");
3332			return -EINVAL;
3333		}
3334
3335		dev_id = dev->id;
3336	}
3337
3338	sp = &sci_ports[dev_id];
3339	platform_set_drvdata(dev, sp);
3340
3341	ret = sci_probe_single(dev, dev_id, p, sp);
3342	if (ret)
3343		return ret;
3344
3345	if (sp->port.fifosize > 1) {
3346		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_trigger);
 
3347		if (ret)
3348			return ret;
3349	}
3350	if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3351	    sp->port.type == PORT_HSCIF) {
3352		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
 
3353		if (ret) {
3354			if (sp->port.fifosize > 1) {
3355				device_remove_file(&dev->dev,
3356						   &dev_attr_rx_fifo_trigger);
3357			}
3358			return ret;
3359		}
3360	}
3361
3362#ifdef CONFIG_SH_STANDARD_BIOS
3363	sh_bios_gdb_detach();
3364#endif
3365
3366	sci_ports_in_use |= BIT(dev_id);
3367	return 0;
3368}
3369
3370static __maybe_unused int sci_suspend(struct device *dev)
3371{
3372	struct sci_port *sport = dev_get_drvdata(dev);
3373
3374	if (sport)
3375		uart_suspend_port(&sci_uart_driver, &sport->port);
3376
3377	return 0;
3378}
3379
3380static __maybe_unused int sci_resume(struct device *dev)
3381{
3382	struct sci_port *sport = dev_get_drvdata(dev);
3383
3384	if (sport)
3385		uart_resume_port(&sci_uart_driver, &sport->port);
3386
3387	return 0;
3388}
3389
3390static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3391
3392static struct platform_driver sci_driver = {
3393	.probe		= sci_probe,
3394	.remove		= sci_remove,
3395	.driver		= {
3396		.name	= "sh-sci",
3397		.pm	= &sci_dev_pm_ops,
3398		.of_match_table = of_match_ptr(of_sci_match),
3399	},
3400};
3401
3402static int __init sci_init(void)
3403{
3404	pr_info("%s\n", banner);
3405
3406	return platform_driver_register(&sci_driver);
3407}
3408
3409static void __exit sci_exit(void)
3410{
3411	platform_driver_unregister(&sci_driver);
3412
3413	if (sci_uart_driver.state)
3414		uart_unregister_driver(&sci_uart_driver);
3415}
3416
3417#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
3418early_platform_init_buffer("earlyprintk", &sci_driver,
3419			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3420#endif
3421#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3422static struct plat_sci_port port_cfg __initdata;
3423
3424static int __init early_console_setup(struct earlycon_device *device,
3425				      int type)
3426{
3427	if (!device->port.membase)
3428		return -ENODEV;
3429
3430	device->port.serial_in = sci_serial_in;
3431	device->port.serial_out	= sci_serial_out;
3432	device->port.type = type;
3433	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3434	port_cfg.type = type;
3435	sci_ports[0].cfg = &port_cfg;
3436	sci_ports[0].params = sci_probe_regmap(&port_cfg);
3437	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3438	sci_serial_out(&sci_ports[0].port, SCSCR,
3439		       SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3440
3441	device->con->write = serial_console_write;
3442	return 0;
3443}
3444static int __init sci_early_console_setup(struct earlycon_device *device,
3445					  const char *opt)
3446{
3447	return early_console_setup(device, PORT_SCI);
3448}
3449static int __init scif_early_console_setup(struct earlycon_device *device,
3450					  const char *opt)
3451{
3452	return early_console_setup(device, PORT_SCIF);
3453}
3454static int __init rzscifa_early_console_setup(struct earlycon_device *device,
3455					  const char *opt)
3456{
3457	port_cfg.regtype = SCIx_RZ_SCIFA_REGTYPE;
3458	return early_console_setup(device, PORT_SCIF);
3459}
3460static int __init scifa_early_console_setup(struct earlycon_device *device,
3461					  const char *opt)
3462{
3463	return early_console_setup(device, PORT_SCIFA);
3464}
3465static int __init scifb_early_console_setup(struct earlycon_device *device,
3466					  const char *opt)
3467{
3468	return early_console_setup(device, PORT_SCIFB);
3469}
3470static int __init hscif_early_console_setup(struct earlycon_device *device,
3471					  const char *opt)
3472{
3473	return early_console_setup(device, PORT_HSCIF);
3474}
3475
3476OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3477OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3478OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rzscifa_early_console_setup);
3479OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3480OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3481OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3482#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3483
3484module_init(sci_init);
3485module_exit(sci_exit);
3486
3487MODULE_LICENSE("GPL");
3488MODULE_ALIAS("platform:sh-sci");
3489MODULE_AUTHOR("Paul Mundt");
3490MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
v4.17
   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#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  19#define SUPPORT_SYSRQ
  20#endif
  21
  22#undef DEBUG
  23
  24#include <linux/clk.h>
  25#include <linux/console.h>
  26#include <linux/ctype.h>
  27#include <linux/cpufreq.h>
  28#include <linux/delay.h>
  29#include <linux/dmaengine.h>
  30#include <linux/dma-mapping.h>
  31#include <linux/err.h>
  32#include <linux/errno.h>
  33#include <linux/init.h>
  34#include <linux/interrupt.h>
  35#include <linux/ioport.h>
  36#include <linux/ktime.h>
  37#include <linux/major.h>
  38#include <linux/module.h>
  39#include <linux/mm.h>
  40#include <linux/of.h>
  41#include <linux/of_device.h>
  42#include <linux/platform_device.h>
  43#include <linux/pm_runtime.h>
  44#include <linux/scatterlist.h>
  45#include <linux/serial.h>
  46#include <linux/serial_sci.h>
  47#include <linux/sh_dma.h>
  48#include <linux/slab.h>
  49#include <linux/string.h>
  50#include <linux/sysrq.h>
  51#include <linux/timer.h>
  52#include <linux/tty.h>
  53#include <linux/tty_flip.h>
  54
  55#ifdef CONFIG_SUPERH
  56#include <asm/sh_bios.h>
  57#endif
  58
  59#include "serial_mctrl_gpio.h"
  60#include "sh-sci.h"
  61
  62/* Offsets into the sci_port->irqs array */
  63enum {
  64	SCIx_ERI_IRQ,
  65	SCIx_RXI_IRQ,
  66	SCIx_TXI_IRQ,
  67	SCIx_BRI_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	dma_cookie_t			cookie_tx;
 139	dma_cookie_t			cookie_rx[2];
 140	dma_cookie_t			active_rx;
 141	dma_addr_t			tx_dma_addr;
 142	unsigned int			tx_dma_len;
 143	struct scatterlist		sg_rx[2];
 144	void				*rx_buf[2];
 145	size_t				buf_len_rx;
 146	struct work_struct		work_tx;
 147	struct hrtimer			rx_timer;
 148	unsigned int			rx_timeout;	/* microseconds */
 149#endif
 150	unsigned int			rx_frame;
 151	int				rx_trigger;
 152	struct timer_list		rx_fifo_timer;
 153	int				rx_fifo_timeout;
 154	u16				hscif_tot;
 155
 156	bool has_rtscts;
 157	bool autorts;
 158};
 159
 160#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
 161
 162static struct sci_port sci_ports[SCI_NPORTS];
 
 163static struct uart_driver sci_uart_driver;
 164
 165static inline struct sci_port *
 166to_sci_port(struct uart_port *uart)
 167{
 168	return container_of(uart, struct sci_port, port);
 169}
 170
 171static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
 172	/*
 173	 * Common SCI definitions, dependent on the port's regshift
 174	 * value.
 175	 */
 176	[SCIx_SCI_REGTYPE] = {
 177		.regs = {
 178			[SCSMR]		= { 0x00,  8 },
 179			[SCBRR]		= { 0x01,  8 },
 180			[SCSCR]		= { 0x02,  8 },
 181			[SCxTDR]	= { 0x03,  8 },
 182			[SCxSR]		= { 0x04,  8 },
 183			[SCxRDR]	= { 0x05,  8 },
 184		},
 185		.fifosize = 1,
 186		.overrun_reg = SCxSR,
 187		.overrun_mask = SCI_ORER,
 188		.sampling_rate_mask = SCI_SR(32),
 189		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 190		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 191	},
 192
 193	/*
 194	 * Common definitions for legacy IrDA ports.
 195	 */
 196	[SCIx_IRDA_REGTYPE] = {
 197		.regs = {
 198			[SCSMR]		= { 0x00,  8 },
 199			[SCBRR]		= { 0x02,  8 },
 200			[SCSCR]		= { 0x04,  8 },
 201			[SCxTDR]	= { 0x06,  8 },
 202			[SCxSR]		= { 0x08, 16 },
 203			[SCxRDR]	= { 0x0a,  8 },
 204			[SCFCR]		= { 0x0c,  8 },
 205			[SCFDR]		= { 0x0e, 16 },
 206		},
 207		.fifosize = 1,
 208		.overrun_reg = SCxSR,
 209		.overrun_mask = SCI_ORER,
 210		.sampling_rate_mask = SCI_SR(32),
 211		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
 212		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
 213	},
 214
 215	/*
 216	 * Common SCIFA definitions.
 217	 */
 218	[SCIx_SCIFA_REGTYPE] = {
 219		.regs = {
 220			[SCSMR]		= { 0x00, 16 },
 221			[SCBRR]		= { 0x04,  8 },
 222			[SCSCR]		= { 0x08, 16 },
 223			[SCxTDR]	= { 0x20,  8 },
 224			[SCxSR]		= { 0x14, 16 },
 225			[SCxRDR]	= { 0x24,  8 },
 226			[SCFCR]		= { 0x18, 16 },
 227			[SCFDR]		= { 0x1c, 16 },
 228			[SCPCR]		= { 0x30, 16 },
 229			[SCPDR]		= { 0x34, 16 },
 230		},
 231		.fifosize = 64,
 232		.overrun_reg = SCxSR,
 233		.overrun_mask = SCIFA_ORER,
 234		.sampling_rate_mask = SCI_SR_SCIFAB,
 235		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 236		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 237	},
 238
 239	/*
 240	 * Common SCIFB definitions.
 241	 */
 242	[SCIx_SCIFB_REGTYPE] = {
 243		.regs = {
 244			[SCSMR]		= { 0x00, 16 },
 245			[SCBRR]		= { 0x04,  8 },
 246			[SCSCR]		= { 0x08, 16 },
 247			[SCxTDR]	= { 0x40,  8 },
 248			[SCxSR]		= { 0x14, 16 },
 249			[SCxRDR]	= { 0x60,  8 },
 250			[SCFCR]		= { 0x18, 16 },
 251			[SCTFDR]	= { 0x38, 16 },
 252			[SCRFDR]	= { 0x3c, 16 },
 253			[SCPCR]		= { 0x30, 16 },
 254			[SCPDR]		= { 0x34, 16 },
 255		},
 256		.fifosize = 256,
 257		.overrun_reg = SCxSR,
 258		.overrun_mask = SCIFA_ORER,
 259		.sampling_rate_mask = SCI_SR_SCIFAB,
 260		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 261		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 262	},
 263
 264	/*
 265	 * Common SH-2(A) SCIF definitions for ports with FIFO data
 266	 * count registers.
 267	 */
 268	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
 269		.regs = {
 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			[SCSPTR]	= { 0x20, 16 },
 279			[SCLSR]		= { 0x24, 16 },
 280		},
 281		.fifosize = 16,
 282		.overrun_reg = SCLSR,
 283		.overrun_mask = SCLSR_ORER,
 284		.sampling_rate_mask = SCI_SR(32),
 285		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 286		.error_clear = SCIF_ERROR_CLEAR,
 287	},
 288
 289	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 290	 * Common SH-3 SCIF definitions.
 291	 */
 292	[SCIx_SH3_SCIF_REGTYPE] = {
 293		.regs = {
 294			[SCSMR]		= { 0x00,  8 },
 295			[SCBRR]		= { 0x02,  8 },
 296			[SCSCR]		= { 0x04,  8 },
 297			[SCxTDR]	= { 0x06,  8 },
 298			[SCxSR]		= { 0x08, 16 },
 299			[SCxRDR]	= { 0x0a,  8 },
 300			[SCFCR]		= { 0x0c,  8 },
 301			[SCFDR]		= { 0x0e, 16 },
 302		},
 303		.fifosize = 16,
 304		.overrun_reg = SCLSR,
 305		.overrun_mask = SCLSR_ORER,
 306		.sampling_rate_mask = SCI_SR(32),
 307		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 308		.error_clear = SCIF_ERROR_CLEAR,
 309	},
 310
 311	/*
 312	 * Common SH-4(A) SCIF(B) definitions.
 313	 */
 314	[SCIx_SH4_SCIF_REGTYPE] = {
 315		.regs = {
 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			[SCSPTR]	= { 0x20, 16 },
 325			[SCLSR]		= { 0x24, 16 },
 326		},
 327		.fifosize = 16,
 328		.overrun_reg = SCLSR,
 329		.overrun_mask = SCLSR_ORER,
 330		.sampling_rate_mask = SCI_SR(32),
 331		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 332		.error_clear = SCIF_ERROR_CLEAR,
 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		.regs = {
 341			[SCSMR]		= { 0x00, 16 },
 342			[SCBRR]		= { 0x04,  8 },
 343			[SCSCR]		= { 0x08, 16 },
 344			[SCxTDR]	= { 0x0c,  8 },
 345			[SCxSR]		= { 0x10, 16 },
 346			[SCxRDR]	= { 0x14,  8 },
 347			[SCFCR]		= { 0x18, 16 },
 348			[SCFDR]		= { 0x1c, 16 },
 349			[SCSPTR]	= { 0x20, 16 },
 350			[SCLSR]		= { 0x24, 16 },
 351			[SCDL]		= { 0x30, 16 },
 352			[SCCKS]		= { 0x34, 16 },
 353		},
 354		.fifosize = 16,
 355		.overrun_reg = SCLSR,
 356		.overrun_mask = SCLSR_ORER,
 357		.sampling_rate_mask = SCI_SR(32),
 358		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 359		.error_clear = SCIF_ERROR_CLEAR,
 360	},
 361
 362	/*
 363	 * Common HSCIF definitions.
 364	 */
 365	[SCIx_HSCIF_REGTYPE] = {
 366		.regs = {
 367			[SCSMR]		= { 0x00, 16 },
 368			[SCBRR]		= { 0x04,  8 },
 369			[SCSCR]		= { 0x08, 16 },
 370			[SCxTDR]	= { 0x0c,  8 },
 371			[SCxSR]		= { 0x10, 16 },
 372			[SCxRDR]	= { 0x14,  8 },
 373			[SCFCR]		= { 0x18, 16 },
 374			[SCFDR]		= { 0x1c, 16 },
 375			[SCSPTR]	= { 0x20, 16 },
 376			[SCLSR]		= { 0x24, 16 },
 377			[HSSRR]		= { 0x40, 16 },
 378			[SCDL]		= { 0x30, 16 },
 379			[SCCKS]		= { 0x34, 16 },
 380			[HSRTRGR]	= { 0x54, 16 },
 381			[HSTTRGR]	= { 0x58, 16 },
 382		},
 383		.fifosize = 128,
 384		.overrun_reg = SCLSR,
 385		.overrun_mask = SCLSR_ORER,
 386		.sampling_rate_mask = SCI_SR_RANGE(8, 32),
 387		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 388		.error_clear = SCIF_ERROR_CLEAR,
 389	},
 390
 391	/*
 392	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
 393	 * register.
 394	 */
 395	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
 396		.regs = {
 397			[SCSMR]		= { 0x00, 16 },
 398			[SCBRR]		= { 0x04,  8 },
 399			[SCSCR]		= { 0x08, 16 },
 400			[SCxTDR]	= { 0x0c,  8 },
 401			[SCxSR]		= { 0x10, 16 },
 402			[SCxRDR]	= { 0x14,  8 },
 403			[SCFCR]		= { 0x18, 16 },
 404			[SCFDR]		= { 0x1c, 16 },
 405			[SCLSR]		= { 0x24, 16 },
 406		},
 407		.fifosize = 16,
 408		.overrun_reg = SCLSR,
 409		.overrun_mask = SCLSR_ORER,
 410		.sampling_rate_mask = SCI_SR(32),
 411		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 412		.error_clear = SCIF_ERROR_CLEAR,
 413	},
 414
 415	/*
 416	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
 417	 * count registers.
 418	 */
 419	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
 420		.regs = {
 421			[SCSMR]		= { 0x00, 16 },
 422			[SCBRR]		= { 0x04,  8 },
 423			[SCSCR]		= { 0x08, 16 },
 424			[SCxTDR]	= { 0x0c,  8 },
 425			[SCxSR]		= { 0x10, 16 },
 426			[SCxRDR]	= { 0x14,  8 },
 427			[SCFCR]		= { 0x18, 16 },
 428			[SCFDR]		= { 0x1c, 16 },
 429			[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
 430			[SCRFDR]	= { 0x20, 16 },
 431			[SCSPTR]	= { 0x24, 16 },
 432			[SCLSR]		= { 0x28, 16 },
 433		},
 434		.fifosize = 16,
 435		.overrun_reg = SCLSR,
 436		.overrun_mask = SCLSR_ORER,
 437		.sampling_rate_mask = SCI_SR(32),
 438		.error_mask = SCIF_DEFAULT_ERROR_MASK,
 439		.error_clear = SCIF_ERROR_CLEAR,
 440	},
 441
 442	/*
 443	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
 444	 * registers.
 445	 */
 446	[SCIx_SH7705_SCIF_REGTYPE] = {
 447		.regs = {
 448			[SCSMR]		= { 0x00, 16 },
 449			[SCBRR]		= { 0x04,  8 },
 450			[SCSCR]		= { 0x08, 16 },
 451			[SCxTDR]	= { 0x20,  8 },
 452			[SCxSR]		= { 0x14, 16 },
 453			[SCxRDR]	= { 0x24,  8 },
 454			[SCFCR]		= { 0x18, 16 },
 455			[SCFDR]		= { 0x1c, 16 },
 456		},
 457		.fifosize = 64,
 458		.overrun_reg = SCxSR,
 459		.overrun_mask = SCIFA_ORER,
 460		.sampling_rate_mask = SCI_SR(16),
 461		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
 462		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
 463	},
 464};
 465
 466#define sci_getreg(up, offset)		(&to_sci_port(up)->params->regs[offset])
 467
 468/*
 469 * The "offset" here is rather misleading, in that it refers to an enum
 470 * value relative to the port mapping rather than the fixed offset
 471 * itself, which needs to be manually retrieved from the platform's
 472 * register map for the given port.
 473 */
 474static unsigned int sci_serial_in(struct uart_port *p, int offset)
 475{
 476	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 477
 478	if (reg->size == 8)
 479		return ioread8(p->membase + (reg->offset << p->regshift));
 480	else if (reg->size == 16)
 481		return ioread16(p->membase + (reg->offset << p->regshift));
 482	else
 483		WARN(1, "Invalid register access\n");
 484
 485	return 0;
 486}
 487
 488static void sci_serial_out(struct uart_port *p, int offset, int value)
 489{
 490	const struct plat_sci_reg *reg = sci_getreg(p, offset);
 491
 492	if (reg->size == 8)
 493		iowrite8(value, p->membase + (reg->offset << p->regshift));
 494	else if (reg->size == 16)
 495		iowrite16(value, p->membase + (reg->offset << p->regshift));
 496	else
 497		WARN(1, "Invalid register access\n");
 498}
 499
 500static void sci_port_enable(struct sci_port *sci_port)
 501{
 502	unsigned int i;
 503
 504	if (!sci_port->port.dev)
 505		return;
 506
 507	pm_runtime_get_sync(sci_port->port.dev);
 508
 509	for (i = 0; i < SCI_NUM_CLKS; i++) {
 510		clk_prepare_enable(sci_port->clks[i]);
 511		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
 512	}
 513	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
 514}
 515
 516static void sci_port_disable(struct sci_port *sci_port)
 517{
 518	unsigned int i;
 519
 520	if (!sci_port->port.dev)
 521		return;
 522
 523	for (i = SCI_NUM_CLKS; i-- > 0; )
 524		clk_disable_unprepare(sci_port->clks[i]);
 525
 526	pm_runtime_put_sync(sci_port->port.dev);
 527}
 528
 529static inline unsigned long port_rx_irq_mask(struct uart_port *port)
 530{
 531	/*
 532	 * Not all ports (such as SCIFA) will support REIE. Rather than
 533	 * special-casing the port type, we check the port initialization
 534	 * IRQ enable mask to see whether the IRQ is desired at all. If
 535	 * it's unset, it's logically inferred that there's no point in
 536	 * testing for it.
 537	 */
 538	return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
 539}
 540
 541static void sci_start_tx(struct uart_port *port)
 542{
 543	struct sci_port *s = to_sci_port(port);
 544	unsigned short ctrl;
 545
 546#ifdef CONFIG_SERIAL_SH_SCI_DMA
 547	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 548		u16 new, scr = serial_port_in(port, SCSCR);
 549		if (s->chan_tx)
 550			new = scr | SCSCR_TDRQE;
 551		else
 552			new = scr & ~SCSCR_TDRQE;
 553		if (new != scr)
 554			serial_port_out(port, SCSCR, new);
 555	}
 556
 557	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
 558	    dma_submit_error(s->cookie_tx)) {
 559		s->cookie_tx = 0;
 560		schedule_work(&s->work_tx);
 561	}
 562#endif
 563
 564	if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 565		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
 566		ctrl = serial_port_in(port, SCSCR);
 567		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
 568	}
 569}
 570
 571static void sci_stop_tx(struct uart_port *port)
 572{
 573	unsigned short ctrl;
 574
 575	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
 576	ctrl = serial_port_in(port, SCSCR);
 577
 578	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 579		ctrl &= ~SCSCR_TDRQE;
 580
 581	ctrl &= ~SCSCR_TIE;
 582
 583	serial_port_out(port, SCSCR, ctrl);
 584}
 585
 586static void sci_start_rx(struct uart_port *port)
 587{
 588	unsigned short ctrl;
 589
 590	ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
 591
 592	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 593		ctrl &= ~SCSCR_RDRQE;
 594
 595	serial_port_out(port, SCSCR, ctrl);
 596}
 597
 598static void sci_stop_rx(struct uart_port *port)
 599{
 600	unsigned short ctrl;
 601
 602	ctrl = serial_port_in(port, SCSCR);
 603
 604	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
 605		ctrl &= ~SCSCR_RDRQE;
 606
 607	ctrl &= ~port_rx_irq_mask(port);
 608
 609	serial_port_out(port, SCSCR, ctrl);
 610}
 611
 612static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
 613{
 614	if (port->type == PORT_SCI) {
 615		/* Just store the mask */
 616		serial_port_out(port, SCxSR, mask);
 617	} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
 618		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
 619		/* Only clear the status bits we want to clear */
 620		serial_port_out(port, SCxSR,
 621				serial_port_in(port, SCxSR) & mask);
 622	} else {
 623		/* Store the mask, clear parity/framing errors */
 624		serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
 625	}
 626}
 627
 628#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
 629    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
 630
 631#ifdef CONFIG_CONSOLE_POLL
 632static int sci_poll_get_char(struct uart_port *port)
 633{
 634	unsigned short status;
 635	int c;
 636
 637	do {
 638		status = serial_port_in(port, SCxSR);
 639		if (status & SCxSR_ERRORS(port)) {
 640			sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
 641			continue;
 642		}
 643		break;
 644	} while (1);
 645
 646	if (!(status & SCxSR_RDxF(port)))
 647		return NO_POLL_CHAR;
 648
 649	c = serial_port_in(port, SCxRDR);
 650
 651	/* Dummy read */
 652	serial_port_in(port, SCxSR);
 653	sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 654
 655	return c;
 656}
 657#endif
 658
 659static void sci_poll_put_char(struct uart_port *port, unsigned char c)
 660{
 661	unsigned short status;
 662
 663	do {
 664		status = serial_port_in(port, SCxSR);
 665	} while (!(status & SCxSR_TDxE(port)));
 666
 667	serial_port_out(port, SCxTDR, c);
 668	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
 669}
 670#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
 671	  CONFIG_SERIAL_SH_SCI_EARLYCON */
 672
 673static void sci_init_pins(struct uart_port *port, unsigned int cflag)
 674{
 675	struct sci_port *s = to_sci_port(port);
 676
 677	/*
 678	 * Use port-specific handler if provided.
 679	 */
 680	if (s->cfg->ops && s->cfg->ops->init_pins) {
 681		s->cfg->ops->init_pins(port, cflag);
 682		return;
 683	}
 684
 685	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
 686		u16 data = serial_port_in(port, SCPDR);
 687		u16 ctrl = serial_port_in(port, SCPCR);
 688
 689		/* Enable RXD and TXD pin functions */
 690		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
 691		if (to_sci_port(port)->has_rtscts) {
 692			/* RTS# is output, active low, unless autorts */
 693			if (!(port->mctrl & TIOCM_RTS)) {
 694				ctrl |= SCPCR_RTSC;
 695				data |= SCPDR_RTSD;
 696			} else if (!s->autorts) {
 697				ctrl |= SCPCR_RTSC;
 698				data &= ~SCPDR_RTSD;
 699			} else {
 700				/* Enable RTS# pin function */
 701				ctrl &= ~SCPCR_RTSC;
 702			}
 703			/* Enable CTS# pin function */
 704			ctrl &= ~SCPCR_CTSC;
 705		}
 706		serial_port_out(port, SCPDR, data);
 707		serial_port_out(port, SCPCR, ctrl);
 708	} else if (sci_getreg(port, SCSPTR)->size) {
 709		u16 status = serial_port_in(port, SCSPTR);
 710
 711		/* RTS# is always output; and active low, unless autorts */
 712		status |= SCSPTR_RTSIO;
 713		if (!(port->mctrl & TIOCM_RTS))
 714			status |= SCSPTR_RTSDT;
 715		else if (!s->autorts)
 716			status &= ~SCSPTR_RTSDT;
 717		/* CTS# and SCK are inputs */
 718		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
 719		serial_port_out(port, SCSPTR, status);
 720	}
 721}
 722
 723static int sci_txfill(struct uart_port *port)
 724{
 725	struct sci_port *s = to_sci_port(port);
 726	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 727	const struct plat_sci_reg *reg;
 728
 729	reg = sci_getreg(port, SCTFDR);
 730	if (reg->size)
 731		return serial_port_in(port, SCTFDR) & fifo_mask;
 732
 733	reg = sci_getreg(port, SCFDR);
 734	if (reg->size)
 735		return serial_port_in(port, SCFDR) >> 8;
 736
 737	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
 738}
 739
 740static int sci_txroom(struct uart_port *port)
 741{
 742	return port->fifosize - sci_txfill(port);
 743}
 744
 745static int sci_rxfill(struct uart_port *port)
 746{
 747	struct sci_port *s = to_sci_port(port);
 748	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
 749	const struct plat_sci_reg *reg;
 750
 751	reg = sci_getreg(port, SCRFDR);
 752	if (reg->size)
 753		return serial_port_in(port, SCRFDR) & fifo_mask;
 754
 755	reg = sci_getreg(port, SCFDR);
 756	if (reg->size)
 757		return serial_port_in(port, SCFDR) & fifo_mask;
 758
 759	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
 760}
 761
 762/* ********************************************************************** *
 763 *                   the interrupt related routines                       *
 764 * ********************************************************************** */
 765
 766static void sci_transmit_chars(struct uart_port *port)
 767{
 768	struct circ_buf *xmit = &port->state->xmit;
 769	unsigned int stopped = uart_tx_stopped(port);
 770	unsigned short status;
 771	unsigned short ctrl;
 772	int count;
 773
 774	status = serial_port_in(port, SCxSR);
 775	if (!(status & SCxSR_TDxE(port))) {
 776		ctrl = serial_port_in(port, SCSCR);
 777		if (uart_circ_empty(xmit))
 778			ctrl &= ~SCSCR_TIE;
 779		else
 780			ctrl |= SCSCR_TIE;
 781		serial_port_out(port, SCSCR, ctrl);
 782		return;
 783	}
 784
 785	count = sci_txroom(port);
 786
 787	do {
 788		unsigned char c;
 789
 790		if (port->x_char) {
 791			c = port->x_char;
 792			port->x_char = 0;
 793		} else if (!uart_circ_empty(xmit) && !stopped) {
 794			c = xmit->buf[xmit->tail];
 795			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 796		} else {
 797			break;
 798		}
 799
 800		serial_port_out(port, SCxTDR, c);
 801
 802		port->icount.tx++;
 803	} while (--count > 0);
 804
 805	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
 806
 807	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 808		uart_write_wakeup(port);
 809	if (uart_circ_empty(xmit)) {
 810		sci_stop_tx(port);
 811	} else {
 812		ctrl = serial_port_in(port, SCSCR);
 813
 814		if (port->type != PORT_SCI) {
 815			serial_port_in(port, SCxSR); /* Dummy read */
 816			sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
 817		}
 818
 819		ctrl |= SCSCR_TIE;
 820		serial_port_out(port, SCSCR, ctrl);
 821	}
 822}
 823
 824/* On SH3, SCIF may read end-of-break as a space->mark char */
 825#define STEPFN(c)  ({int __c = (c); (((__c-1)|(__c)) == -1); })
 826
 827static void sci_receive_chars(struct uart_port *port)
 828{
 829	struct tty_port *tport = &port->state->port;
 830	int i, count, copied = 0;
 831	unsigned short status;
 832	unsigned char flag;
 833
 834	status = serial_port_in(port, SCxSR);
 835	if (!(status & SCxSR_RDxF(port)))
 836		return;
 837
 838	while (1) {
 839		/* Don't copy more bytes than there is room for in the buffer */
 840		count = tty_buffer_request_room(tport, sci_rxfill(port));
 841
 842		/* If for any reason we can't copy more data, we're done! */
 843		if (count == 0)
 844			break;
 845
 846		if (port->type == PORT_SCI) {
 847			char c = serial_port_in(port, SCxRDR);
 848			if (uart_handle_sysrq_char(port, c))
 849				count = 0;
 850			else
 851				tty_insert_flip_char(tport, c, TTY_NORMAL);
 852		} else {
 853			for (i = 0; i < count; i++) {
 854				char c = serial_port_in(port, SCxRDR);
 855
 856				status = serial_port_in(port, SCxSR);
 857				if (uart_handle_sysrq_char(port, c)) {
 858					count--; i--;
 859					continue;
 860				}
 861
 862				/* Store data and status */
 863				if (status & SCxSR_FER(port)) {
 864					flag = TTY_FRAME;
 865					port->icount.frame++;
 866					dev_notice(port->dev, "frame error\n");
 867				} else if (status & SCxSR_PER(port)) {
 868					flag = TTY_PARITY;
 869					port->icount.parity++;
 870					dev_notice(port->dev, "parity error\n");
 871				} else
 872					flag = TTY_NORMAL;
 873
 874				tty_insert_flip_char(tport, c, flag);
 875			}
 876		}
 877
 878		serial_port_in(port, SCxSR); /* dummy read */
 879		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 880
 881		copied += count;
 882		port->icount.rx += count;
 883	}
 884
 885	if (copied) {
 886		/* Tell the rest of the system the news. New characters! */
 887		tty_flip_buffer_push(tport);
 888	} else {
 889		/* TTY buffers full; read from RX reg to prevent lockup */
 890		serial_port_in(port, SCxRDR);
 891		serial_port_in(port, SCxSR); /* dummy read */
 892		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
 893	}
 894}
 895
 896static int sci_handle_errors(struct uart_port *port)
 897{
 898	int copied = 0;
 899	unsigned short status = serial_port_in(port, SCxSR);
 900	struct tty_port *tport = &port->state->port;
 901	struct sci_port *s = to_sci_port(port);
 902
 903	/* Handle overruns */
 904	if (status & s->params->overrun_mask) {
 905		port->icount.overrun++;
 906
 907		/* overrun error */
 908		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
 909			copied++;
 910
 911		dev_notice(port->dev, "overrun error\n");
 912	}
 913
 914	if (status & SCxSR_FER(port)) {
 915		/* frame error */
 916		port->icount.frame++;
 917
 918		if (tty_insert_flip_char(tport, 0, TTY_FRAME))
 919			copied++;
 920
 921		dev_notice(port->dev, "frame error\n");
 922	}
 923
 924	if (status & SCxSR_PER(port)) {
 925		/* parity error */
 926		port->icount.parity++;
 927
 928		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
 929			copied++;
 930
 931		dev_notice(port->dev, "parity error\n");
 932	}
 933
 934	if (copied)
 935		tty_flip_buffer_push(tport);
 936
 937	return copied;
 938}
 939
 940static int sci_handle_fifo_overrun(struct uart_port *port)
 941{
 942	struct tty_port *tport = &port->state->port;
 943	struct sci_port *s = to_sci_port(port);
 944	const struct plat_sci_reg *reg;
 945	int copied = 0;
 946	u16 status;
 947
 948	reg = sci_getreg(port, s->params->overrun_reg);
 949	if (!reg->size)
 950		return 0;
 951
 952	status = serial_port_in(port, s->params->overrun_reg);
 953	if (status & s->params->overrun_mask) {
 954		status &= ~s->params->overrun_mask;
 955		serial_port_out(port, s->params->overrun_reg, status);
 956
 957		port->icount.overrun++;
 958
 959		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
 960		tty_flip_buffer_push(tport);
 961
 962		dev_dbg(port->dev, "overrun error\n");
 963		copied++;
 964	}
 965
 966	return copied;
 967}
 968
 969static int sci_handle_breaks(struct uart_port *port)
 970{
 971	int copied = 0;
 972	unsigned short status = serial_port_in(port, SCxSR);
 973	struct tty_port *tport = &port->state->port;
 974
 975	if (uart_handle_break(port))
 976		return 0;
 977
 978	if (status & SCxSR_BRK(port)) {
 979		port->icount.brk++;
 980
 981		/* Notify of BREAK */
 982		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
 983			copied++;
 984
 985		dev_dbg(port->dev, "BREAK detected\n");
 986	}
 987
 988	if (copied)
 989		tty_flip_buffer_push(tport);
 990
 991	copied += sci_handle_fifo_overrun(port);
 992
 993	return copied;
 994}
 995
 996static int scif_set_rtrg(struct uart_port *port, int rx_trig)
 997{
 998	unsigned int bits;
 999
1000	if (rx_trig < 1)
1001		rx_trig = 1;
1002	if (rx_trig >= port->fifosize)
1003		rx_trig = port->fifosize;
1004
1005	/* HSCIF can be set to an arbitrary level. */
1006	if (sci_getreg(port, HSRTRGR)->size) {
1007		serial_port_out(port, HSRTRGR, rx_trig);
1008		return rx_trig;
1009	}
1010
1011	switch (port->type) {
1012	case PORT_SCIF:
1013		if (rx_trig < 4) {
1014			bits = 0;
1015			rx_trig = 1;
1016		} else if (rx_trig < 8) {
1017			bits = SCFCR_RTRG0;
1018			rx_trig = 4;
1019		} else if (rx_trig < 14) {
1020			bits = SCFCR_RTRG1;
1021			rx_trig = 8;
1022		} else {
1023			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1024			rx_trig = 14;
1025		}
1026		break;
1027	case PORT_SCIFA:
1028	case PORT_SCIFB:
1029		if (rx_trig < 16) {
1030			bits = 0;
1031			rx_trig = 1;
1032		} else if (rx_trig < 32) {
1033			bits = SCFCR_RTRG0;
1034			rx_trig = 16;
1035		} else if (rx_trig < 48) {
1036			bits = SCFCR_RTRG1;
1037			rx_trig = 32;
1038		} else {
1039			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1040			rx_trig = 48;
1041		}
1042		break;
1043	default:
1044		WARN(1, "unknown FIFO configuration");
1045		return 1;
1046	}
1047
1048	serial_port_out(port, SCFCR,
1049		(serial_port_in(port, SCFCR) &
1050		~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1051
1052	return rx_trig;
1053}
1054
1055static int scif_rtrg_enabled(struct uart_port *port)
1056{
1057	if (sci_getreg(port, HSRTRGR)->size)
1058		return serial_port_in(port, HSRTRGR) != 0;
1059	else
1060		return (serial_port_in(port, SCFCR) &
1061			(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1062}
1063
1064static void rx_fifo_timer_fn(struct timer_list *t)
1065{
1066	struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1067	struct uart_port *port = &s->port;
1068
1069	dev_dbg(port->dev, "Rx timed out\n");
1070	scif_set_rtrg(port, 1);
1071}
1072
1073static ssize_t rx_trigger_show(struct device *dev,
1074			       struct device_attribute *attr,
1075			       char *buf)
1076{
1077	struct uart_port *port = dev_get_drvdata(dev);
1078	struct sci_port *sci = to_sci_port(port);
1079
1080	return sprintf(buf, "%d\n", sci->rx_trigger);
1081}
1082
1083static ssize_t rx_trigger_store(struct device *dev,
1084				struct device_attribute *attr,
1085				const char *buf,
1086				size_t count)
1087{
1088	struct uart_port *port = dev_get_drvdata(dev);
1089	struct sci_port *sci = to_sci_port(port);
1090	int ret;
1091	long r;
1092
1093	ret = kstrtol(buf, 0, &r);
1094	if (ret)
1095		return ret;
1096
1097	sci->rx_trigger = scif_set_rtrg(port, r);
1098	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1099		scif_set_rtrg(port, 1);
1100
1101	return count;
1102}
1103
1104static DEVICE_ATTR(rx_fifo_trigger, 0644, rx_trigger_show, rx_trigger_store);
1105
1106static ssize_t rx_fifo_timeout_show(struct device *dev,
1107			       struct device_attribute *attr,
1108			       char *buf)
1109{
1110	struct uart_port *port = dev_get_drvdata(dev);
1111	struct sci_port *sci = to_sci_port(port);
1112	int v;
1113
1114	if (port->type == PORT_HSCIF)
1115		v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1116	else
1117		v = sci->rx_fifo_timeout;
1118
1119	return sprintf(buf, "%d\n", v);
1120}
1121
1122static ssize_t rx_fifo_timeout_store(struct device *dev,
1123				struct device_attribute *attr,
1124				const char *buf,
1125				size_t count)
1126{
1127	struct uart_port *port = dev_get_drvdata(dev);
1128	struct sci_port *sci = to_sci_port(port);
1129	int ret;
1130	long r;
1131
1132	ret = kstrtol(buf, 0, &r);
1133	if (ret)
1134		return ret;
1135
1136	if (port->type == PORT_HSCIF) {
1137		if (r < 0 || r > 3)
1138			return -EINVAL;
1139		sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1140	} else {
1141		sci->rx_fifo_timeout = r;
1142		scif_set_rtrg(port, 1);
1143		if (r > 0)
1144			timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1145	}
1146
1147	return count;
1148}
1149
1150static DEVICE_ATTR_RW(rx_fifo_timeout);
1151
1152
1153#ifdef CONFIG_SERIAL_SH_SCI_DMA
1154static void sci_dma_tx_complete(void *arg)
1155{
1156	struct sci_port *s = arg;
1157	struct uart_port *port = &s->port;
1158	struct circ_buf *xmit = &port->state->xmit;
1159	unsigned long flags;
1160
1161	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1162
1163	spin_lock_irqsave(&port->lock, flags);
1164
1165	xmit->tail += s->tx_dma_len;
1166	xmit->tail &= UART_XMIT_SIZE - 1;
1167
1168	port->icount.tx += s->tx_dma_len;
1169
1170	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1171		uart_write_wakeup(port);
1172
1173	if (!uart_circ_empty(xmit)) {
1174		s->cookie_tx = 0;
1175		schedule_work(&s->work_tx);
1176	} else {
1177		s->cookie_tx = -EINVAL;
1178		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1179			u16 ctrl = serial_port_in(port, SCSCR);
1180			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1181		}
1182	}
1183
1184	spin_unlock_irqrestore(&port->lock, flags);
1185}
1186
1187/* Locking: called with port lock held */
1188static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1189{
1190	struct uart_port *port = &s->port;
1191	struct tty_port *tport = &port->state->port;
1192	int copied;
1193
1194	copied = tty_insert_flip_string(tport, buf, count);
1195	if (copied < count)
1196		port->icount.buf_overrun++;
1197
1198	port->icount.rx += copied;
1199
1200	return copied;
1201}
1202
1203static int sci_dma_rx_find_active(struct sci_port *s)
1204{
1205	unsigned int i;
1206
1207	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1208		if (s->active_rx == s->cookie_rx[i])
1209			return i;
1210
1211	return -1;
1212}
1213
1214static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
1215{
1216	struct dma_chan *chan = s->chan_rx;
1217	struct uart_port *port = &s->port;
1218	unsigned long flags;
1219
1220	spin_lock_irqsave(&port->lock, flags);
1221	s->chan_rx = NULL;
1222	s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1223	spin_unlock_irqrestore(&port->lock, flags);
1224	dmaengine_terminate_all(chan);
 
 
 
 
 
 
 
 
 
1225	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1226			  sg_dma_address(&s->sg_rx[0]));
1227	dma_release_channel(chan);
1228	if (enable_pio) {
1229		spin_lock_irqsave(&port->lock, flags);
1230		sci_start_rx(port);
1231		spin_unlock_irqrestore(&port->lock, flags);
1232	}
1233}
1234
1235static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1236{
1237	long sec = usec / 1000000;
1238	long nsec = (usec % 1000000) * 1000;
1239	ktime_t t = ktime_set(sec, nsec);
1240
1241	hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1242}
1243
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1244static void sci_dma_rx_complete(void *arg)
1245{
1246	struct sci_port *s = arg;
1247	struct dma_chan *chan = s->chan_rx;
1248	struct uart_port *port = &s->port;
1249	struct dma_async_tx_descriptor *desc;
1250	unsigned long flags;
1251	int active, count = 0;
1252
1253	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1254		s->active_rx);
1255
1256	spin_lock_irqsave(&port->lock, flags);
1257
1258	active = sci_dma_rx_find_active(s);
1259	if (active >= 0)
1260		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1261
1262	start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1263
1264	if (count)
1265		tty_flip_buffer_push(&port->state->port);
1266
1267	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1268				       DMA_DEV_TO_MEM,
1269				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1270	if (!desc)
1271		goto fail;
1272
1273	desc->callback = sci_dma_rx_complete;
1274	desc->callback_param = s;
1275	s->cookie_rx[active] = dmaengine_submit(desc);
1276	if (dma_submit_error(s->cookie_rx[active]))
1277		goto fail;
1278
1279	s->active_rx = s->cookie_rx[!active];
1280
1281	dma_async_issue_pending(chan);
1282
1283	spin_unlock_irqrestore(&port->lock, flags);
1284	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1285		__func__, s->cookie_rx[active], active, s->active_rx);
1286	return;
1287
1288fail:
1289	spin_unlock_irqrestore(&port->lock, flags);
1290	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1291	sci_rx_dma_release(s, true);
 
 
 
 
 
1292}
1293
1294static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
1295{
1296	struct dma_chan *chan = s->chan_tx;
1297	struct uart_port *port = &s->port;
1298	unsigned long flags;
1299
1300	spin_lock_irqsave(&port->lock, flags);
1301	s->chan_tx = NULL;
1302	s->cookie_tx = -EINVAL;
1303	spin_unlock_irqrestore(&port->lock, flags);
1304	dmaengine_terminate_all(chan);
1305	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1306			 DMA_TO_DEVICE);
1307	dma_release_channel(chan);
1308	if (enable_pio) {
1309		spin_lock_irqsave(&port->lock, flags);
1310		sci_start_tx(port);
1311		spin_unlock_irqrestore(&port->lock, flags);
1312	}
1313}
1314
1315static void sci_submit_rx(struct sci_port *s)
1316{
1317	struct dma_chan *chan = s->chan_rx;
 
 
1318	int i;
1319
1320	for (i = 0; i < 2; i++) {
1321		struct scatterlist *sg = &s->sg_rx[i];
1322		struct dma_async_tx_descriptor *desc;
1323
1324		desc = dmaengine_prep_slave_sg(chan,
1325			sg, 1, DMA_DEV_TO_MEM,
1326			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1327		if (!desc)
1328			goto fail;
1329
1330		desc->callback = sci_dma_rx_complete;
1331		desc->callback_param = s;
1332		s->cookie_rx[i] = dmaengine_submit(desc);
1333		if (dma_submit_error(s->cookie_rx[i]))
1334			goto fail;
1335
1336	}
1337
1338	s->active_rx = s->cookie_rx[0];
1339
1340	dma_async_issue_pending(chan);
1341	return;
1342
1343fail:
 
 
 
1344	if (i)
1345		dmaengine_terminate_all(chan);
1346	for (i = 0; i < 2; i++)
1347		s->cookie_rx[i] = -EINVAL;
1348	s->active_rx = -EINVAL;
1349	sci_rx_dma_release(s, true);
 
1350}
1351
1352static void work_fn_tx(struct work_struct *work)
1353{
1354	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1355	struct dma_async_tx_descriptor *desc;
1356	struct dma_chan *chan = s->chan_tx;
1357	struct uart_port *port = &s->port;
1358	struct circ_buf *xmit = &port->state->xmit;
 
1359	dma_addr_t buf;
 
1360
1361	/*
1362	 * DMA is idle now.
1363	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1364	 * offsets and lengths. Since it is a circular buffer, we have to
1365	 * transmit till the end, and then the rest. Take the port lock to get a
1366	 * consistent xmit buffer state.
1367	 */
1368	spin_lock_irq(&port->lock);
1369	buf = s->tx_dma_addr + (xmit->tail & (UART_XMIT_SIZE - 1));
 
 
1370	s->tx_dma_len = min_t(unsigned int,
1371		CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1372		CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1373	spin_unlock_irq(&port->lock);
 
 
 
 
1374
1375	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1376					   DMA_MEM_TO_DEV,
1377					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1378	if (!desc) {
 
1379		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1380		/* switch to PIO */
1381		sci_tx_dma_release(s, true);
1382		return;
1383	}
1384
1385	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1386				   DMA_TO_DEVICE);
1387
1388	spin_lock_irq(&port->lock);
1389	desc->callback = sci_dma_tx_complete;
1390	desc->callback_param = s;
1391	spin_unlock_irq(&port->lock);
1392	s->cookie_tx = dmaengine_submit(desc);
1393	if (dma_submit_error(s->cookie_tx)) {
 
1394		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1395		/* switch to PIO */
1396		sci_tx_dma_release(s, true);
1397		return;
1398	}
1399
 
1400	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1401		__func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1402
1403	dma_async_issue_pending(chan);
 
 
 
 
 
 
 
 
1404}
1405
1406static enum hrtimer_restart rx_timer_fn(struct hrtimer *t)
1407{
1408	struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1409	struct dma_chan *chan = s->chan_rx;
1410	struct uart_port *port = &s->port;
1411	struct dma_tx_state state;
1412	enum dma_status status;
1413	unsigned long flags;
1414	unsigned int read;
1415	int active, count;
1416	u16 scr;
1417
1418	dev_dbg(port->dev, "DMA Rx timed out\n");
1419
1420	spin_lock_irqsave(&port->lock, flags);
1421
1422	active = sci_dma_rx_find_active(s);
1423	if (active < 0) {
1424		spin_unlock_irqrestore(&port->lock, flags);
1425		return HRTIMER_NORESTART;
1426	}
1427
1428	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1429	if (status == DMA_COMPLETE) {
1430		spin_unlock_irqrestore(&port->lock, flags);
1431		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1432			s->active_rx, active);
1433
1434		/* Let packet complete handler take care of the packet */
1435		return HRTIMER_NORESTART;
1436	}
1437
1438	dmaengine_pause(chan);
1439
1440	/*
1441	 * sometimes DMA transfer doesn't stop even if it is stopped and
1442	 * data keeps on coming until transaction is complete so check
1443	 * for DMA_COMPLETE again
1444	 * Let packet complete handler take care of the packet
1445	 */
1446	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1447	if (status == DMA_COMPLETE) {
1448		spin_unlock_irqrestore(&port->lock, flags);
1449		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1450		return HRTIMER_NORESTART;
1451	}
1452
1453	/* Handle incomplete DMA receive */
1454	dmaengine_terminate_all(s->chan_rx);
1455	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1456
1457	if (read) {
1458		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1459		if (count)
1460			tty_flip_buffer_push(&port->state->port);
1461	}
1462
1463	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1464		sci_submit_rx(s);
1465
1466	/* Direct new serial port interrupts back to CPU */
1467	scr = serial_port_in(port, SCSCR);
1468	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1469		scr &= ~SCSCR_RDRQE;
1470		enable_irq(s->irqs[SCIx_RXI_IRQ]);
1471	}
1472	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1473
1474	spin_unlock_irqrestore(&port->lock, flags);
1475
1476	return HRTIMER_NORESTART;
1477}
1478
1479static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1480					     enum dma_transfer_direction dir)
1481{
1482	struct dma_chan *chan;
1483	struct dma_slave_config cfg;
1484	int ret;
1485
1486	chan = dma_request_slave_channel(port->dev,
1487					 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1488	if (!chan) {
1489		dev_warn(port->dev, "dma_request_slave_channel failed\n");
1490		return NULL;
1491	}
1492
1493	memset(&cfg, 0, sizeof(cfg));
1494	cfg.direction = dir;
1495	if (dir == DMA_MEM_TO_DEV) {
1496		cfg.dst_addr = port->mapbase +
1497			(sci_getreg(port, SCxTDR)->offset << port->regshift);
1498		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1499	} else {
1500		cfg.src_addr = port->mapbase +
1501			(sci_getreg(port, SCxRDR)->offset << port->regshift);
1502		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1503	}
1504
1505	ret = dmaengine_slave_config(chan, &cfg);
1506	if (ret) {
1507		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1508		dma_release_channel(chan);
1509		return NULL;
1510	}
1511
1512	return chan;
1513}
1514
1515static void sci_request_dma(struct uart_port *port)
1516{
1517	struct sci_port *s = to_sci_port(port);
1518	struct dma_chan *chan;
1519
1520	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1521
 
 
 
 
 
 
 
1522	if (!port->dev->of_node)
1523		return;
1524
1525	s->cookie_tx = -EINVAL;
1526
1527	/*
1528	 * Don't request a dma channel if no channel was specified
1529	 * in the device tree.
1530	 */
1531	if (!of_find_property(port->dev->of_node, "dmas", NULL))
1532		return;
1533
1534	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1535	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1536	if (chan) {
1537		s->chan_tx = chan;
1538		/* UART circular tx buffer is an aligned page. */
1539		s->tx_dma_addr = dma_map_single(chan->device->dev,
1540						port->state->xmit.buf,
1541						UART_XMIT_SIZE,
1542						DMA_TO_DEVICE);
1543		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1544			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1545			dma_release_channel(chan);
1546			s->chan_tx = NULL;
1547		} else {
1548			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1549				__func__, UART_XMIT_SIZE,
1550				port->state->xmit.buf, &s->tx_dma_addr);
 
 
 
1551		}
1552
1553		INIT_WORK(&s->work_tx, work_fn_tx);
1554	}
1555
1556	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1557	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1558	if (chan) {
1559		unsigned int i;
1560		dma_addr_t dma;
1561		void *buf;
1562
1563		s->chan_rx = chan;
1564
1565		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1566		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1567					 &dma, GFP_KERNEL);
1568		if (!buf) {
1569			dev_warn(port->dev,
1570				 "Failed to allocate Rx dma buffer, using PIO\n");
1571			dma_release_channel(chan);
1572			s->chan_rx = NULL;
1573			return;
1574		}
1575
1576		for (i = 0; i < 2; i++) {
1577			struct scatterlist *sg = &s->sg_rx[i];
1578
1579			sg_init_table(sg, 1);
1580			s->rx_buf[i] = buf;
1581			sg_dma_address(sg) = dma;
1582			sg_dma_len(sg) = s->buf_len_rx;
1583
1584			buf += s->buf_len_rx;
1585			dma += s->buf_len_rx;
1586		}
1587
1588		hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1589		s->rx_timer.function = rx_timer_fn;
 
 
1590
1591		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1592			sci_submit_rx(s);
1593	}
1594}
1595
1596static void sci_free_dma(struct uart_port *port)
1597{
1598	struct sci_port *s = to_sci_port(port);
1599
1600	if (s->chan_tx)
1601		sci_tx_dma_release(s, false);
1602	if (s->chan_rx)
1603		sci_rx_dma_release(s, false);
1604}
1605
1606static void sci_flush_buffer(struct uart_port *port)
1607{
 
 
1608	/*
1609	 * In uart_flush_buffer(), the xmit circular buffer has just been
1610	 * cleared, so we have to reset tx_dma_len accordingly.
 
1611	 */
1612	to_sci_port(port)->tx_dma_len = 0;
 
 
 
 
1613}
1614#else /* !CONFIG_SERIAL_SH_SCI_DMA */
1615static inline void sci_request_dma(struct uart_port *port)
1616{
1617}
1618
1619static inline void sci_free_dma(struct uart_port *port)
1620{
1621}
1622
1623#define sci_flush_buffer	NULL
1624#endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1625
1626static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1627{
1628	struct uart_port *port = ptr;
1629	struct sci_port *s = to_sci_port(port);
1630
1631#ifdef CONFIG_SERIAL_SH_SCI_DMA
1632	if (s->chan_rx) {
1633		u16 scr = serial_port_in(port, SCSCR);
1634		u16 ssr = serial_port_in(port, SCxSR);
1635
1636		/* Disable future Rx interrupts */
1637		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1638			disable_irq_nosync(irq);
1639			scr |= SCSCR_RDRQE;
1640		} else {
 
 
 
1641			scr &= ~SCSCR_RIE;
1642			sci_submit_rx(s);
1643		}
1644		serial_port_out(port, SCSCR, scr);
1645		/* Clear current interrupt */
1646		serial_port_out(port, SCxSR,
1647				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1648		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1649			jiffies, s->rx_timeout);
1650		start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1651
1652		return IRQ_HANDLED;
1653	}
 
 
1654#endif
1655
1656	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1657		if (!scif_rtrg_enabled(port))
1658			scif_set_rtrg(port, s->rx_trigger);
1659
1660		mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1661			  s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1662	}
1663
1664	/* I think sci_receive_chars has to be called irrespective
1665	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1666	 * to be disabled?
1667	 */
1668	sci_receive_chars(ptr);
1669
1670	return IRQ_HANDLED;
1671}
1672
1673static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1674{
1675	struct uart_port *port = ptr;
1676	unsigned long flags;
1677
1678	spin_lock_irqsave(&port->lock, flags);
1679	sci_transmit_chars(port);
1680	spin_unlock_irqrestore(&port->lock, flags);
1681
1682	return IRQ_HANDLED;
1683}
1684
 
 
 
 
 
 
 
 
 
 
 
1685static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1686{
1687	struct uart_port *port = ptr;
1688	struct sci_port *s = to_sci_port(port);
1689
 
 
 
 
 
 
 
 
 
 
 
 
 
1690	/* Handle errors */
1691	if (port->type == PORT_SCI) {
1692		if (sci_handle_errors(port)) {
1693			/* discard character in rx buffer */
1694			serial_port_in(port, SCxSR);
1695			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1696		}
1697	} else {
1698		sci_handle_fifo_overrun(port);
1699		if (!s->chan_rx)
1700			sci_receive_chars(ptr);
1701	}
1702
1703	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1704
1705	/* Kick the transmission */
1706	if (!s->chan_tx)
1707		sci_tx_interrupt(irq, ptr);
1708
1709	return IRQ_HANDLED;
1710}
1711
1712static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1713{
1714	struct uart_port *port = ptr;
1715
1716	/* Handle BREAKs */
1717	sci_handle_breaks(port);
1718	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1719
1720	return IRQ_HANDLED;
1721}
1722
1723static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1724{
1725	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1726	struct uart_port *port = ptr;
1727	struct sci_port *s = to_sci_port(port);
1728	irqreturn_t ret = IRQ_NONE;
1729
1730	ssr_status = serial_port_in(port, SCxSR);
1731	scr_status = serial_port_in(port, SCSCR);
1732	if (s->params->overrun_reg == SCxSR)
1733		orer_status = ssr_status;
1734	else if (sci_getreg(port, s->params->overrun_reg)->size)
1735		orer_status = serial_port_in(port, s->params->overrun_reg);
1736
1737	err_enabled = scr_status & port_rx_irq_mask(port);
1738
1739	/* Tx Interrupt */
1740	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1741	    !s->chan_tx)
1742		ret = sci_tx_interrupt(irq, ptr);
1743
1744	/*
1745	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1746	 * DR flags
1747	 */
1748	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1749	    (scr_status & SCSCR_RIE))
1750		ret = sci_rx_interrupt(irq, ptr);
1751
1752	/* Error Interrupt */
1753	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1754		ret = sci_er_interrupt(irq, ptr);
1755
1756	/* Break Interrupt */
1757	if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1758		ret = sci_br_interrupt(irq, ptr);
1759
1760	/* Overrun Interrupt */
1761	if (orer_status & s->params->overrun_mask) {
1762		sci_handle_fifo_overrun(port);
1763		ret = IRQ_HANDLED;
1764	}
1765
1766	return ret;
1767}
1768
1769static const struct sci_irq_desc {
1770	const char	*desc;
1771	irq_handler_t	handler;
1772} sci_irq_desc[] = {
1773	/*
1774	 * Split out handlers, the default case.
1775	 */
1776	[SCIx_ERI_IRQ] = {
1777		.desc = "rx err",
1778		.handler = sci_er_interrupt,
1779	},
1780
1781	[SCIx_RXI_IRQ] = {
1782		.desc = "rx full",
1783		.handler = sci_rx_interrupt,
1784	},
1785
1786	[SCIx_TXI_IRQ] = {
1787		.desc = "tx empty",
1788		.handler = sci_tx_interrupt,
1789	},
1790
1791	[SCIx_BRI_IRQ] = {
1792		.desc = "break",
1793		.handler = sci_br_interrupt,
1794	},
1795
 
 
 
 
 
 
 
 
 
 
1796	/*
1797	 * Special muxed handler.
1798	 */
1799	[SCIx_MUX_IRQ] = {
1800		.desc = "mux",
1801		.handler = sci_mpxed_interrupt,
1802	},
1803};
1804
1805static int sci_request_irq(struct sci_port *port)
1806{
1807	struct uart_port *up = &port->port;
1808	int i, j, ret = 0;
1809
1810	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1811		const struct sci_irq_desc *desc;
1812		int irq;
1813
 
 
 
 
 
 
 
1814		if (SCIx_IRQ_IS_MUXED(port)) {
1815			i = SCIx_MUX_IRQ;
1816			irq = up->irq;
1817		} else {
1818			irq = port->irqs[i];
1819
1820			/*
1821			 * Certain port types won't support all of the
1822			 * available interrupt sources.
1823			 */
1824			if (unlikely(irq < 0))
1825				continue;
1826		}
1827
1828		desc = sci_irq_desc + i;
1829		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1830					    dev_name(up->dev), desc->desc);
1831		if (!port->irqstr[j]) {
1832			ret = -ENOMEM;
1833			goto out_nomem;
1834		}
1835
1836		ret = request_irq(irq, desc->handler, up->irqflags,
1837				  port->irqstr[j], port);
1838		if (unlikely(ret)) {
1839			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1840			goto out_noirq;
1841		}
1842	}
1843
1844	return 0;
1845
1846out_noirq:
1847	while (--i >= 0)
1848		free_irq(port->irqs[i], port);
1849
1850out_nomem:
1851	while (--j >= 0)
1852		kfree(port->irqstr[j]);
1853
1854	return ret;
1855}
1856
1857static void sci_free_irq(struct sci_port *port)
1858{
1859	int i;
1860
1861	/*
1862	 * Intentionally in reverse order so we iterate over the muxed
1863	 * IRQ first.
1864	 */
1865	for (i = 0; i < SCIx_NR_IRQS; i++) {
1866		int irq = port->irqs[i];
1867
1868		/*
1869		 * Certain port types won't support all of the available
1870		 * interrupt sources.
1871		 */
1872		if (unlikely(irq < 0))
1873			continue;
1874
 
 
 
 
 
 
 
1875		free_irq(port->irqs[i], port);
1876		kfree(port->irqstr[i]);
1877
1878		if (SCIx_IRQ_IS_MUXED(port)) {
1879			/* If there's only one IRQ, we're done. */
1880			return;
1881		}
1882	}
1883}
1884
1885static unsigned int sci_tx_empty(struct uart_port *port)
1886{
1887	unsigned short status = serial_port_in(port, SCxSR);
1888	unsigned short in_tx_fifo = sci_txfill(port);
1889
1890	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1891}
1892
1893static void sci_set_rts(struct uart_port *port, bool state)
1894{
1895	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1896		u16 data = serial_port_in(port, SCPDR);
1897
1898		/* Active low */
1899		if (state)
1900			data &= ~SCPDR_RTSD;
1901		else
1902			data |= SCPDR_RTSD;
1903		serial_port_out(port, SCPDR, data);
1904
1905		/* RTS# is output */
1906		serial_port_out(port, SCPCR,
1907				serial_port_in(port, SCPCR) | SCPCR_RTSC);
1908	} else if (sci_getreg(port, SCSPTR)->size) {
1909		u16 ctrl = serial_port_in(port, SCSPTR);
1910
1911		/* Active low */
1912		if (state)
1913			ctrl &= ~SCSPTR_RTSDT;
1914		else
1915			ctrl |= SCSPTR_RTSDT;
1916		serial_port_out(port, SCSPTR, ctrl);
1917	}
1918}
1919
1920static bool sci_get_cts(struct uart_port *port)
1921{
1922	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1923		/* Active low */
1924		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
1925	} else if (sci_getreg(port, SCSPTR)->size) {
1926		/* Active low */
1927		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
1928	}
1929
1930	return true;
1931}
1932
1933/*
1934 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
1935 * CTS/RTS is supported in hardware by at least one port and controlled
1936 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
1937 * handled via the ->init_pins() op, which is a bit of a one-way street,
1938 * lacking any ability to defer pin control -- this will later be
1939 * converted over to the GPIO framework).
1940 *
1941 * Other modes (such as loopback) are supported generically on certain
1942 * port types, but not others. For these it's sufficient to test for the
1943 * existence of the support register and simply ignore the port type.
1944 */
1945static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
1946{
1947	struct sci_port *s = to_sci_port(port);
1948
1949	if (mctrl & TIOCM_LOOP) {
1950		const struct plat_sci_reg *reg;
1951
1952		/*
1953		 * Standard loopback mode for SCFCR ports.
1954		 */
1955		reg = sci_getreg(port, SCFCR);
1956		if (reg->size)
1957			serial_port_out(port, SCFCR,
1958					serial_port_in(port, SCFCR) |
1959					SCFCR_LOOP);
1960	}
1961
1962	mctrl_gpio_set(s->gpios, mctrl);
1963
1964	if (!s->has_rtscts)
1965		return;
1966
1967	if (!(mctrl & TIOCM_RTS)) {
1968		/* Disable Auto RTS */
1969		serial_port_out(port, SCFCR,
1970				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
1971
1972		/* Clear RTS */
1973		sci_set_rts(port, 0);
1974	} else if (s->autorts) {
1975		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1976			/* Enable RTS# pin function */
1977			serial_port_out(port, SCPCR,
1978				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
1979		}
1980
1981		/* Enable Auto RTS */
1982		serial_port_out(port, SCFCR,
1983				serial_port_in(port, SCFCR) | SCFCR_MCE);
1984	} else {
1985		/* Set RTS */
1986		sci_set_rts(port, 1);
1987	}
1988}
1989
1990static unsigned int sci_get_mctrl(struct uart_port *port)
1991{
1992	struct sci_port *s = to_sci_port(port);
1993	struct mctrl_gpios *gpios = s->gpios;
1994	unsigned int mctrl = 0;
1995
1996	mctrl_gpio_get(gpios, &mctrl);
1997
1998	/*
1999	 * CTS/RTS is handled in hardware when supported, while nothing
2000	 * else is wired up.
2001	 */
2002	if (s->autorts) {
2003		if (sci_get_cts(port))
2004			mctrl |= TIOCM_CTS;
2005	} else if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS))) {
2006		mctrl |= TIOCM_CTS;
2007	}
2008	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR)))
2009		mctrl |= TIOCM_DSR;
2010	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD)))
2011		mctrl |= TIOCM_CAR;
2012
2013	return mctrl;
2014}
2015
2016static void sci_enable_ms(struct uart_port *port)
2017{
2018	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2019}
2020
2021static void sci_break_ctl(struct uart_port *port, int break_state)
2022{
2023	unsigned short scscr, scsptr;
2024	unsigned long flags;
2025
2026	/* check wheter the port has SCSPTR */
2027	if (!sci_getreg(port, SCSPTR)->size) {
2028		/*
2029		 * Not supported by hardware. Most parts couple break and rx
2030		 * interrupts together, with break detection always enabled.
2031		 */
2032		return;
2033	}
2034
2035	spin_lock_irqsave(&port->lock, flags);
2036	scsptr = serial_port_in(port, SCSPTR);
2037	scscr = serial_port_in(port, SCSCR);
2038
2039	if (break_state == -1) {
2040		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2041		scscr &= ~SCSCR_TE;
2042	} else {
2043		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2044		scscr |= SCSCR_TE;
2045	}
2046
2047	serial_port_out(port, SCSPTR, scsptr);
2048	serial_port_out(port, SCSCR, scscr);
2049	spin_unlock_irqrestore(&port->lock, flags);
2050}
2051
2052static int sci_startup(struct uart_port *port)
2053{
2054	struct sci_port *s = to_sci_port(port);
2055	int ret;
2056
2057	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2058
2059	sci_request_dma(port);
2060
2061	ret = sci_request_irq(s);
2062	if (unlikely(ret < 0)) {
2063		sci_free_dma(port);
2064		return ret;
2065	}
2066
2067	return 0;
2068}
2069
2070static void sci_shutdown(struct uart_port *port)
2071{
2072	struct sci_port *s = to_sci_port(port);
2073	unsigned long flags;
2074	u16 scr;
2075
2076	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2077
2078	s->autorts = false;
2079	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2080
2081	spin_lock_irqsave(&port->lock, flags);
2082	sci_stop_rx(port);
2083	sci_stop_tx(port);
2084	/*
2085	 * Stop RX and TX, disable related interrupts, keep clock source
2086	 * and HSCIF TOT bits
2087	 */
2088	scr = serial_port_in(port, SCSCR);
2089	serial_port_out(port, SCSCR, scr &
2090			(SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2091	spin_unlock_irqrestore(&port->lock, flags);
2092
2093#ifdef CONFIG_SERIAL_SH_SCI_DMA
2094	if (s->chan_rx) {
2095		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2096			port->line);
2097		hrtimer_cancel(&s->rx_timer);
2098	}
2099#endif
2100
 
 
2101	sci_free_irq(s);
2102	sci_free_dma(port);
2103}
2104
2105static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2106			unsigned int *srr)
2107{
2108	unsigned long freq = s->clk_rates[SCI_SCK];
2109	int err, min_err = INT_MAX;
2110	unsigned int sr;
2111
2112	if (s->port.type != PORT_HSCIF)
2113		freq *= 2;
2114
2115	for_each_sr(sr, s) {
2116		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2117		if (abs(err) >= abs(min_err))
2118			continue;
2119
2120		min_err = err;
2121		*srr = sr - 1;
2122
2123		if (!err)
2124			break;
2125	}
2126
2127	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2128		*srr + 1);
2129	return min_err;
2130}
2131
2132static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2133			unsigned long freq, unsigned int *dlr,
2134			unsigned int *srr)
2135{
2136	int err, min_err = INT_MAX;
2137	unsigned int sr, dl;
2138
2139	if (s->port.type != PORT_HSCIF)
2140		freq *= 2;
2141
2142	for_each_sr(sr, s) {
2143		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2144		dl = clamp(dl, 1U, 65535U);
2145
2146		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2147		if (abs(err) >= abs(min_err))
2148			continue;
2149
2150		min_err = err;
2151		*dlr = dl;
2152		*srr = sr - 1;
2153
2154		if (!err)
2155			break;
2156	}
2157
2158	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2159		min_err, *dlr, *srr + 1);
2160	return min_err;
2161}
2162
2163/* calculate sample rate, BRR, and clock select */
2164static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2165			  unsigned int *brr, unsigned int *srr,
2166			  unsigned int *cks)
2167{
2168	unsigned long freq = s->clk_rates[SCI_FCK];
2169	unsigned int sr, br, prediv, scrate, c;
2170	int err, min_err = INT_MAX;
2171
2172	if (s->port.type != PORT_HSCIF)
2173		freq *= 2;
2174
2175	/*
2176	 * Find the combination of sample rate and clock select with the
2177	 * smallest deviation from the desired baud rate.
2178	 * Prefer high sample rates to maximise the receive margin.
2179	 *
2180	 * M: Receive margin (%)
2181	 * N: Ratio of bit rate to clock (N = sampling rate)
2182	 * D: Clock duty (D = 0 to 1.0)
2183	 * L: Frame length (L = 9 to 12)
2184	 * F: Absolute value of clock frequency deviation
2185	 *
2186	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2187	 *      (|D - 0.5| / N * (1 + F))|
2188	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2189	 */
2190	for_each_sr(sr, s) {
2191		for (c = 0; c <= 3; c++) {
2192			/* integerized formulas from HSCIF documentation */
2193			prediv = sr * (1 << (2 * c + 1));
2194
2195			/*
2196			 * We need to calculate:
2197			 *
2198			 *     br = freq / (prediv * bps) clamped to [1..256]
2199			 *     err = freq / (br * prediv) - bps
2200			 *
2201			 * Watch out for overflow when calculating the desired
2202			 * sampling clock rate!
2203			 */
2204			if (bps > UINT_MAX / prediv)
2205				break;
2206
2207			scrate = prediv * bps;
2208			br = DIV_ROUND_CLOSEST(freq, scrate);
2209			br = clamp(br, 1U, 256U);
2210
2211			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2212			if (abs(err) >= abs(min_err))
2213				continue;
2214
2215			min_err = err;
2216			*brr = br - 1;
2217			*srr = sr - 1;
2218			*cks = c;
2219
2220			if (!err)
2221				goto found;
2222		}
2223	}
2224
2225found:
2226	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2227		min_err, *brr, *srr + 1, *cks);
2228	return min_err;
2229}
2230
2231static void sci_reset(struct uart_port *port)
2232{
2233	const struct plat_sci_reg *reg;
2234	unsigned int status;
2235	struct sci_port *s = to_sci_port(port);
2236
2237	serial_port_out(port, SCSCR, s->hscif_tot);	/* TE=0, RE=0, CKE1=0 */
2238
2239	reg = sci_getreg(port, SCFCR);
2240	if (reg->size)
2241		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2242
2243	sci_clear_SCxSR(port,
2244			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2245			SCxSR_BREAK_CLEAR(port));
2246	if (sci_getreg(port, SCLSR)->size) {
2247		status = serial_port_in(port, SCLSR);
2248		status &= ~(SCLSR_TO | SCLSR_ORER);
2249		serial_port_out(port, SCLSR, status);
2250	}
2251
2252	if (s->rx_trigger > 1) {
2253		if (s->rx_fifo_timeout) {
2254			scif_set_rtrg(port, 1);
2255			timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2256		} else {
2257			if (port->type == PORT_SCIFA ||
2258			    port->type == PORT_SCIFB)
2259				scif_set_rtrg(port, 1);
2260			else
2261				scif_set_rtrg(port, s->rx_trigger);
2262		}
2263	}
2264}
2265
2266static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2267			    struct ktermios *old)
2268{
2269	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2270	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2271	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2272	struct sci_port *s = to_sci_port(port);
2273	const struct plat_sci_reg *reg;
2274	int min_err = INT_MAX, err;
2275	unsigned long max_freq = 0;
2276	int best_clk = -1;
2277	unsigned long flags;
2278
2279	if ((termios->c_cflag & CSIZE) == CS7)
2280		smr_val |= SCSMR_CHR;
2281	if (termios->c_cflag & PARENB)
2282		smr_val |= SCSMR_PE;
2283	if (termios->c_cflag & PARODD)
2284		smr_val |= SCSMR_PE | SCSMR_ODD;
2285	if (termios->c_cflag & CSTOPB)
2286		smr_val |= SCSMR_STOP;
2287
2288	/*
2289	 * earlyprintk comes here early on with port->uartclk set to zero.
2290	 * the clock framework is not up and running at this point so here
2291	 * we assume that 115200 is the maximum baud rate. please note that
2292	 * the baud rate is not programmed during earlyprintk - it is assumed
2293	 * that the previous boot loader has enabled required clocks and
2294	 * setup the baud rate generator hardware for us already.
2295	 */
2296	if (!port->uartclk) {
2297		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2298		goto done;
2299	}
2300
2301	for (i = 0; i < SCI_NUM_CLKS; i++)
2302		max_freq = max(max_freq, s->clk_rates[i]);
2303
2304	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2305	if (!baud)
2306		goto done;
2307
2308	/*
2309	 * There can be multiple sources for the sampling clock.  Find the one
2310	 * that gives us the smallest deviation from the desired baud rate.
2311	 */
2312
2313	/* Optional Undivided External Clock */
2314	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2315	    port->type != PORT_SCIFB) {
2316		err = sci_sck_calc(s, baud, &srr1);
2317		if (abs(err) < abs(min_err)) {
2318			best_clk = SCI_SCK;
2319			scr_val = SCSCR_CKE1;
2320			sccks = SCCKS_CKS;
2321			min_err = err;
2322			srr = srr1;
2323			if (!err)
2324				goto done;
2325		}
2326	}
2327
2328	/* Optional BRG Frequency Divided External Clock */
2329	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2330		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2331				   &srr1);
2332		if (abs(err) < abs(min_err)) {
2333			best_clk = SCI_SCIF_CLK;
2334			scr_val = SCSCR_CKE1;
2335			sccks = 0;
2336			min_err = err;
2337			dl = dl1;
2338			srr = srr1;
2339			if (!err)
2340				goto done;
2341		}
2342	}
2343
2344	/* Optional BRG Frequency Divided Internal Clock */
2345	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2346		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2347				   &srr1);
2348		if (abs(err) < abs(min_err)) {
2349			best_clk = SCI_BRG_INT;
2350			scr_val = SCSCR_CKE1;
2351			sccks = SCCKS_XIN;
2352			min_err = err;
2353			dl = dl1;
2354			srr = srr1;
2355			if (!min_err)
2356				goto done;
2357		}
2358	}
2359
2360	/* Divided Functional Clock using standard Bit Rate Register */
2361	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2362	if (abs(err) < abs(min_err)) {
2363		best_clk = SCI_FCK;
2364		scr_val = 0;
2365		min_err = err;
2366		brr = brr1;
2367		srr = srr1;
2368		cks = cks1;
2369	}
2370
2371done:
2372	if (best_clk >= 0)
2373		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2374			s->clks[best_clk], baud, min_err);
2375
2376	sci_port_enable(s);
2377
2378	/*
2379	 * Program the optional External Baud Rate Generator (BRG) first.
2380	 * It controls the mux to select (H)SCK or frequency divided clock.
2381	 */
2382	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2383		serial_port_out(port, SCDL, dl);
2384		serial_port_out(port, SCCKS, sccks);
2385	}
2386
2387	spin_lock_irqsave(&port->lock, flags);
2388
2389	sci_reset(port);
2390
2391	uart_update_timeout(port, termios->c_cflag, baud);
2392
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2393	if (best_clk >= 0) {
2394		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2395			switch (srr + 1) {
2396			case 5:  smr_val |= SCSMR_SRC_5;  break;
2397			case 7:  smr_val |= SCSMR_SRC_7;  break;
2398			case 11: smr_val |= SCSMR_SRC_11; break;
2399			case 13: smr_val |= SCSMR_SRC_13; break;
2400			case 16: smr_val |= SCSMR_SRC_16; break;
2401			case 17: smr_val |= SCSMR_SRC_17; break;
2402			case 19: smr_val |= SCSMR_SRC_19; break;
2403			case 27: smr_val |= SCSMR_SRC_27; break;
2404			}
2405		smr_val |= cks;
2406		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2407		serial_port_out(port, SCSMR, smr_val);
2408		serial_port_out(port, SCBRR, brr);
2409		if (sci_getreg(port, HSSRR)->size)
2410			serial_port_out(port, HSSRR, srr | HSCIF_SRE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2411
2412		/* Wait one bit interval */
2413		udelay((1000000 + (baud - 1)) / baud);
2414	} else {
2415		/* Don't touch the bit rate configuration */
2416		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2417		smr_val |= serial_port_in(port, SCSMR) &
2418			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2419		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2420		serial_port_out(port, SCSMR, smr_val);
2421	}
2422
2423	sci_init_pins(port, termios->c_cflag);
2424
2425	port->status &= ~UPSTAT_AUTOCTS;
2426	s->autorts = false;
2427	reg = sci_getreg(port, SCFCR);
2428	if (reg->size) {
2429		unsigned short ctrl = serial_port_in(port, SCFCR);
2430
2431		if ((port->flags & UPF_HARD_FLOW) &&
2432		    (termios->c_cflag & CRTSCTS)) {
2433			/* There is no CTS interrupt to restart the hardware */
2434			port->status |= UPSTAT_AUTOCTS;
2435			/* MCE is enabled when RTS is raised */
2436			s->autorts = true;
2437		}
2438
2439		/*
2440		 * As we've done a sci_reset() above, ensure we don't
2441		 * interfere with the FIFOs while toggling MCE. As the
2442		 * reset values could still be set, simply mask them out.
2443		 */
2444		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2445
2446		serial_port_out(port, SCFCR, ctrl);
2447	}
2448	if (port->flags & UPF_HARD_FLOW) {
2449		/* Refresh (Auto) RTS */
2450		sci_set_mctrl(port, port->mctrl);
2451	}
2452
2453	scr_val |= SCSCR_RE | SCSCR_TE |
2454		   (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2455	serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2456	if ((srr + 1 == 5) &&
2457	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2458		/*
2459		 * In asynchronous mode, when the sampling rate is 1/5, first
2460		 * received data may become invalid on some SCIFA and SCIFB.
2461		 * To avoid this problem wait more than 1 serial data time (1
2462		 * bit time x serial data number) after setting SCSCR.RE = 1.
2463		 */
2464		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2465	}
2466
2467	/*
2468	 * Calculate delay for 2 DMA buffers (4 FIFO).
2469	 * See serial_core.c::uart_update_timeout().
2470	 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2471	 * function calculates 1 jiffie for the data plus 5 jiffies for the
2472	 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2473	 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2474	 * value obtained by this formula is too small. Therefore, if the value
2475	 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2476	 */
2477	/* byte size and parity */
2478	switch (termios->c_cflag & CSIZE) {
2479	case CS5:
2480		bits = 7;
2481		break;
2482	case CS6:
2483		bits = 8;
2484		break;
2485	case CS7:
2486		bits = 9;
2487		break;
2488	default:
2489		bits = 10;
2490		break;
2491	}
2492
2493	if (termios->c_cflag & CSTOPB)
2494		bits++;
2495	if (termios->c_cflag & PARENB)
2496		bits++;
2497
2498	s->rx_frame = (10000 * bits) / (baud / 100);
2499#ifdef CONFIG_SERIAL_SH_SCI_DMA
2500	s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2501	if (s->rx_timeout < 20)
2502		s->rx_timeout = 20;
2503#endif
2504
2505	if ((termios->c_cflag & CREAD) != 0)
2506		sci_start_rx(port);
2507
2508	spin_unlock_irqrestore(&port->lock, flags);
2509
2510	sci_port_disable(s);
2511
2512	if (UART_ENABLE_MS(port, termios->c_cflag))
2513		sci_enable_ms(port);
2514}
2515
2516static void sci_pm(struct uart_port *port, unsigned int state,
2517		   unsigned int oldstate)
2518{
2519	struct sci_port *sci_port = to_sci_port(port);
2520
2521	switch (state) {
2522	case UART_PM_STATE_OFF:
2523		sci_port_disable(sci_port);
2524		break;
2525	default:
2526		sci_port_enable(sci_port);
2527		break;
2528	}
2529}
2530
2531static const char *sci_type(struct uart_port *port)
2532{
2533	switch (port->type) {
2534	case PORT_IRDA:
2535		return "irda";
2536	case PORT_SCI:
2537		return "sci";
2538	case PORT_SCIF:
2539		return "scif";
2540	case PORT_SCIFA:
2541		return "scifa";
2542	case PORT_SCIFB:
2543		return "scifb";
2544	case PORT_HSCIF:
2545		return "hscif";
2546	}
2547
2548	return NULL;
2549}
2550
2551static int sci_remap_port(struct uart_port *port)
2552{
2553	struct sci_port *sport = to_sci_port(port);
2554
2555	/*
2556	 * Nothing to do if there's already an established membase.
2557	 */
2558	if (port->membase)
2559		return 0;
2560
2561	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2562		port->membase = ioremap_nocache(port->mapbase, sport->reg_size);
2563		if (unlikely(!port->membase)) {
2564			dev_err(port->dev, "can't remap port#%d\n", port->line);
2565			return -ENXIO;
2566		}
2567	} else {
2568		/*
2569		 * For the simple (and majority of) cases where we don't
2570		 * need to do any remapping, just cast the cookie
2571		 * directly.
2572		 */
2573		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2574	}
2575
2576	return 0;
2577}
2578
2579static void sci_release_port(struct uart_port *port)
2580{
2581	struct sci_port *sport = to_sci_port(port);
2582
2583	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2584		iounmap(port->membase);
2585		port->membase = NULL;
2586	}
2587
2588	release_mem_region(port->mapbase, sport->reg_size);
2589}
2590
2591static int sci_request_port(struct uart_port *port)
2592{
2593	struct resource *res;
2594	struct sci_port *sport = to_sci_port(port);
2595	int ret;
2596
2597	res = request_mem_region(port->mapbase, sport->reg_size,
2598				 dev_name(port->dev));
2599	if (unlikely(res == NULL)) {
2600		dev_err(port->dev, "request_mem_region failed.");
2601		return -EBUSY;
2602	}
2603
2604	ret = sci_remap_port(port);
2605	if (unlikely(ret != 0)) {
2606		release_resource(res);
2607		return ret;
2608	}
2609
2610	return 0;
2611}
2612
2613static void sci_config_port(struct uart_port *port, int flags)
2614{
2615	if (flags & UART_CONFIG_TYPE) {
2616		struct sci_port *sport = to_sci_port(port);
2617
2618		port->type = sport->cfg->type;
2619		sci_request_port(port);
2620	}
2621}
2622
2623static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2624{
2625	if (ser->baud_base < 2400)
2626		/* No paper tape reader for Mitch.. */
2627		return -EINVAL;
2628
2629	return 0;
2630}
2631
2632static const struct uart_ops sci_uart_ops = {
2633	.tx_empty	= sci_tx_empty,
2634	.set_mctrl	= sci_set_mctrl,
2635	.get_mctrl	= sci_get_mctrl,
2636	.start_tx	= sci_start_tx,
2637	.stop_tx	= sci_stop_tx,
2638	.stop_rx	= sci_stop_rx,
2639	.enable_ms	= sci_enable_ms,
2640	.break_ctl	= sci_break_ctl,
2641	.startup	= sci_startup,
2642	.shutdown	= sci_shutdown,
2643	.flush_buffer	= sci_flush_buffer,
2644	.set_termios	= sci_set_termios,
2645	.pm		= sci_pm,
2646	.type		= sci_type,
2647	.release_port	= sci_release_port,
2648	.request_port	= sci_request_port,
2649	.config_port	= sci_config_port,
2650	.verify_port	= sci_verify_port,
2651#ifdef CONFIG_CONSOLE_POLL
2652	.poll_get_char	= sci_poll_get_char,
2653	.poll_put_char	= sci_poll_put_char,
2654#endif
2655};
2656
2657static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2658{
2659	const char *clk_names[] = {
2660		[SCI_FCK] = "fck",
2661		[SCI_SCK] = "sck",
2662		[SCI_BRG_INT] = "brg_int",
2663		[SCI_SCIF_CLK] = "scif_clk",
2664	};
2665	struct clk *clk;
2666	unsigned int i;
2667
2668	if (sci_port->cfg->type == PORT_HSCIF)
2669		clk_names[SCI_SCK] = "hsck";
2670
2671	for (i = 0; i < SCI_NUM_CLKS; i++) {
2672		clk = devm_clk_get(dev, clk_names[i]);
2673		if (PTR_ERR(clk) == -EPROBE_DEFER)
2674			return -EPROBE_DEFER;
2675
2676		if (IS_ERR(clk) && i == SCI_FCK) {
2677			/*
2678			 * "fck" used to be called "sci_ick", and we need to
2679			 * maintain DT backward compatibility.
2680			 */
2681			clk = devm_clk_get(dev, "sci_ick");
2682			if (PTR_ERR(clk) == -EPROBE_DEFER)
2683				return -EPROBE_DEFER;
2684
2685			if (!IS_ERR(clk))
2686				goto found;
2687
2688			/*
2689			 * Not all SH platforms declare a clock lookup entry
2690			 * for SCI devices, in which case we need to get the
2691			 * global "peripheral_clk" clock.
2692			 */
2693			clk = devm_clk_get(dev, "peripheral_clk");
2694			if (!IS_ERR(clk))
2695				goto found;
2696
2697			dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2698				PTR_ERR(clk));
2699			return PTR_ERR(clk);
2700		}
2701
2702found:
2703		if (IS_ERR(clk))
2704			dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2705				PTR_ERR(clk));
2706		else
2707			dev_dbg(dev, "clk %s is %pC rate %pCr\n", clk_names[i],
2708				clk, clk);
2709		sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2710	}
2711	return 0;
2712}
2713
2714static const struct sci_port_params *
2715sci_probe_regmap(const struct plat_sci_port *cfg)
2716{
2717	unsigned int regtype;
2718
2719	if (cfg->regtype != SCIx_PROBE_REGTYPE)
2720		return &sci_port_params[cfg->regtype];
2721
2722	switch (cfg->type) {
2723	case PORT_SCI:
2724		regtype = SCIx_SCI_REGTYPE;
2725		break;
2726	case PORT_IRDA:
2727		regtype = SCIx_IRDA_REGTYPE;
2728		break;
2729	case PORT_SCIFA:
2730		regtype = SCIx_SCIFA_REGTYPE;
2731		break;
2732	case PORT_SCIFB:
2733		regtype = SCIx_SCIFB_REGTYPE;
2734		break;
2735	case PORT_SCIF:
2736		/*
2737		 * The SH-4 is a bit of a misnomer here, although that's
2738		 * where this particular port layout originated. This
2739		 * configuration (or some slight variation thereof)
2740		 * remains the dominant model for all SCIFs.
2741		 */
2742		regtype = SCIx_SH4_SCIF_REGTYPE;
2743		break;
2744	case PORT_HSCIF:
2745		regtype = SCIx_HSCIF_REGTYPE;
2746		break;
2747	default:
2748		pr_err("Can't probe register map for given port\n");
2749		return NULL;
2750	}
2751
2752	return &sci_port_params[regtype];
2753}
2754
2755static int sci_init_single(struct platform_device *dev,
2756			   struct sci_port *sci_port, unsigned int index,
2757			   const struct plat_sci_port *p, bool early)
2758{
2759	struct uart_port *port = &sci_port->port;
2760	const struct resource *res;
2761	unsigned int i;
2762	int ret;
2763
2764	sci_port->cfg	= p;
2765
2766	port->ops	= &sci_uart_ops;
2767	port->iotype	= UPIO_MEM;
2768	port->line	= index;
2769
2770	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2771	if (res == NULL)
2772		return -ENOMEM;
2773
2774	port->mapbase = res->start;
2775	sci_port->reg_size = resource_size(res);
2776
2777	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i)
2778		sci_port->irqs[i] = platform_get_irq(dev, i);
 
 
 
 
2779
2780	/* The SCI generates several interrupts. They can be muxed together or
2781	 * connected to different interrupt lines. In the muxed case only one
2782	 * interrupt resource is specified. In the non-muxed case three or four
2783	 * interrupt resources are specified, as the BRI interrupt is optional.
 
 
2784	 */
2785	if (sci_port->irqs[0] < 0)
2786		return -ENXIO;
2787
2788	if (sci_port->irqs[1] < 0) {
2789		sci_port->irqs[1] = sci_port->irqs[0];
2790		sci_port->irqs[2] = sci_port->irqs[0];
2791		sci_port->irqs[3] = sci_port->irqs[0];
2792	}
2793
2794	sci_port->params = sci_probe_regmap(p);
2795	if (unlikely(sci_port->params == NULL))
2796		return -EINVAL;
2797
2798	switch (p->type) {
2799	case PORT_SCIFB:
2800		sci_port->rx_trigger = 48;
2801		break;
2802	case PORT_HSCIF:
2803		sci_port->rx_trigger = 64;
2804		break;
2805	case PORT_SCIFA:
2806		sci_port->rx_trigger = 32;
2807		break;
2808	case PORT_SCIF:
2809		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2810			/* RX triggering not implemented for this IP */
2811			sci_port->rx_trigger = 1;
2812		else
2813			sci_port->rx_trigger = 8;
2814		break;
2815	default:
2816		sci_port->rx_trigger = 1;
2817		break;
2818	}
2819
2820	sci_port->rx_fifo_timeout = 0;
2821	sci_port->hscif_tot = 0;
2822
2823	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2824	 * match the SoC datasheet, this should be investigated. Let platform
2825	 * data override the sampling rate for now.
2826	 */
2827	sci_port->sampling_rate_mask = p->sampling_rate
2828				     ? SCI_SR(p->sampling_rate)
2829				     : sci_port->params->sampling_rate_mask;
2830
2831	if (!early) {
2832		ret = sci_init_clocks(sci_port, &dev->dev);
2833		if (ret < 0)
2834			return ret;
2835
2836		port->dev = &dev->dev;
2837
2838		pm_runtime_enable(&dev->dev);
2839	}
2840
2841	port->type		= p->type;
2842	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2843	port->fifosize		= sci_port->params->fifosize;
2844
2845	if (port->type == PORT_SCI) {
2846		if (sci_port->reg_size >= 0x20)
2847			port->regshift = 2;
2848		else
2849			port->regshift = 1;
2850	}
2851
2852	/*
2853	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2854	 * for the multi-IRQ ports, which is where we are primarily
2855	 * concerned with the shutdown path synchronization.
2856	 *
2857	 * For the muxed case there's nothing more to do.
2858	 */
2859	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
2860	port->irqflags		= 0;
2861
2862	port->serial_in		= sci_serial_in;
2863	port->serial_out	= sci_serial_out;
2864
2865	return 0;
2866}
2867
2868static void sci_cleanup_single(struct sci_port *port)
2869{
2870	pm_runtime_disable(port->port.dev);
2871}
2872
2873#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2874    defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2875static void serial_console_putchar(struct uart_port *port, int ch)
2876{
2877	sci_poll_put_char(port, ch);
2878}
2879
2880/*
2881 *	Print a string to the serial port trying not to disturb
2882 *	any possible real use of the port...
2883 */
2884static void serial_console_write(struct console *co, const char *s,
2885				 unsigned count)
2886{
2887	struct sci_port *sci_port = &sci_ports[co->index];
2888	struct uart_port *port = &sci_port->port;
2889	unsigned short bits, ctrl, ctrl_temp;
2890	unsigned long flags;
2891	int locked = 1;
2892
2893	local_irq_save(flags);
2894#if defined(SUPPORT_SYSRQ)
2895	if (port->sysrq)
2896		locked = 0;
2897	else
2898#endif
2899	if (oops_in_progress)
2900		locked = spin_trylock(&port->lock);
2901	else
2902		spin_lock(&port->lock);
2903
2904	/* first save SCSCR then disable interrupts, keep clock source */
2905	ctrl = serial_port_in(port, SCSCR);
2906	ctrl_temp = SCSCR_RE | SCSCR_TE |
2907		    (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
2908		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
2909	serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
2910
2911	uart_console_write(port, s, count, serial_console_putchar);
2912
2913	/* wait until fifo is empty and last bit has been transmitted */
2914	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
2915	while ((serial_port_in(port, SCxSR) & bits) != bits)
2916		cpu_relax();
2917
2918	/* restore the SCSCR */
2919	serial_port_out(port, SCSCR, ctrl);
2920
2921	if (locked)
2922		spin_unlock(&port->lock);
2923	local_irq_restore(flags);
2924}
2925
2926static int serial_console_setup(struct console *co, char *options)
2927{
2928	struct sci_port *sci_port;
2929	struct uart_port *port;
2930	int baud = 115200;
2931	int bits = 8;
2932	int parity = 'n';
2933	int flow = 'n';
2934	int ret;
2935
2936	/*
2937	 * Refuse to handle any bogus ports.
2938	 */
2939	if (co->index < 0 || co->index >= SCI_NPORTS)
2940		return -ENODEV;
2941
2942	sci_port = &sci_ports[co->index];
2943	port = &sci_port->port;
2944
2945	/*
2946	 * Refuse to handle uninitialized ports.
2947	 */
2948	if (!port->ops)
2949		return -ENODEV;
2950
2951	ret = sci_remap_port(port);
2952	if (unlikely(ret != 0))
2953		return ret;
2954
2955	if (options)
2956		uart_parse_options(options, &baud, &parity, &bits, &flow);
2957
2958	return uart_set_options(port, co, baud, parity, bits, flow);
2959}
2960
2961static struct console serial_console = {
2962	.name		= "ttySC",
2963	.device		= uart_console_device,
2964	.write		= serial_console_write,
2965	.setup		= serial_console_setup,
2966	.flags		= CON_PRINTBUFFER,
2967	.index		= -1,
2968	.data		= &sci_uart_driver,
2969};
2970
2971static struct console early_serial_console = {
2972	.name           = "early_ttySC",
2973	.write          = serial_console_write,
2974	.flags          = CON_PRINTBUFFER,
2975	.index		= -1,
2976};
2977
2978static char early_serial_buf[32];
2979
2980static int sci_probe_earlyprintk(struct platform_device *pdev)
2981{
2982	const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
2983
2984	if (early_serial_console.data)
2985		return -EEXIST;
2986
2987	early_serial_console.index = pdev->id;
2988
2989	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
2990
2991	serial_console_setup(&early_serial_console, early_serial_buf);
2992
2993	if (!strstr(early_serial_buf, "keep"))
2994		early_serial_console.flags |= CON_BOOT;
2995
2996	register_console(&early_serial_console);
2997	return 0;
2998}
2999
3000#define SCI_CONSOLE	(&serial_console)
3001
3002#else
3003static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3004{
3005	return -EINVAL;
3006}
3007
3008#define SCI_CONSOLE	NULL
3009
3010#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3011
3012static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3013
3014static DEFINE_MUTEX(sci_uart_registration_lock);
3015static struct uart_driver sci_uart_driver = {
3016	.owner		= THIS_MODULE,
3017	.driver_name	= "sci",
3018	.dev_name	= "ttySC",
3019	.major		= SCI_MAJOR,
3020	.minor		= SCI_MINOR_START,
3021	.nr		= SCI_NPORTS,
3022	.cons		= SCI_CONSOLE,
3023};
3024
3025static int sci_remove(struct platform_device *dev)
3026{
3027	struct sci_port *port = platform_get_drvdata(dev);
 
3028
 
3029	uart_remove_one_port(&sci_uart_driver, &port->port);
3030
3031	sci_cleanup_single(port);
3032
3033	if (port->port.fifosize > 1) {
3034		sysfs_remove_file(&dev->dev.kobj,
3035				  &dev_attr_rx_fifo_trigger.attr);
3036	}
3037	if (port->port.type == PORT_SCIFA || port->port.type == PORT_SCIFB ||
3038	    port->port.type == PORT_HSCIF) {
3039		sysfs_remove_file(&dev->dev.kobj,
3040				  &dev_attr_rx_fifo_timeout.attr);
3041	}
3042
3043	return 0;
3044}
3045
3046
3047#define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
3048#define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
3049#define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
3050
3051static const struct of_device_id of_sci_match[] = {
3052	/* SoC-specific types */
3053	{
3054		.compatible = "renesas,scif-r7s72100",
3055		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3056	},
 
 
 
 
3057	/* Family-specific types */
3058	{
3059		.compatible = "renesas,rcar-gen1-scif",
3060		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3061	}, {
3062		.compatible = "renesas,rcar-gen2-scif",
3063		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3064	}, {
3065		.compatible = "renesas,rcar-gen3-scif",
3066		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3067	},
3068	/* Generic types */
3069	{
3070		.compatible = "renesas,scif",
3071		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3072	}, {
3073		.compatible = "renesas,scifa",
3074		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3075	}, {
3076		.compatible = "renesas,scifb",
3077		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3078	}, {
3079		.compatible = "renesas,hscif",
3080		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3081	}, {
3082		.compatible = "renesas,sci",
3083		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3084	}, {
3085		/* Terminator */
3086	},
3087};
3088MODULE_DEVICE_TABLE(of, of_sci_match);
3089
3090static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3091					  unsigned int *dev_id)
3092{
3093	struct device_node *np = pdev->dev.of_node;
3094	struct plat_sci_port *p;
3095	struct sci_port *sp;
3096	const void *data;
3097	int id;
3098
3099	if (!IS_ENABLED(CONFIG_OF) || !np)
3100		return NULL;
3101
3102	data = of_device_get_match_data(&pdev->dev);
3103
3104	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3105	if (!p)
3106		return NULL;
3107
3108	/* Get the line number from the aliases node. */
3109	id = of_alias_get_id(np, "serial");
 
 
3110	if (id < 0) {
3111		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3112		return NULL;
3113	}
3114	if (id >= ARRAY_SIZE(sci_ports)) {
3115		dev_err(&pdev->dev, "serial%d out of range\n", id);
3116		return NULL;
3117	}
3118
3119	sp = &sci_ports[id];
3120	*dev_id = id;
3121
3122	p->type = SCI_OF_TYPE(data);
3123	p->regtype = SCI_OF_REGTYPE(data);
3124
3125	sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3126
3127	return p;
3128}
3129
3130static int sci_probe_single(struct platform_device *dev,
3131				      unsigned int index,
3132				      struct plat_sci_port *p,
3133				      struct sci_port *sciport)
3134{
3135	int ret;
3136
3137	/* Sanity check */
3138	if (unlikely(index >= SCI_NPORTS)) {
3139		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3140			   index+1, SCI_NPORTS);
3141		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3142		return -EINVAL;
3143	}
 
 
 
3144
3145	mutex_lock(&sci_uart_registration_lock);
3146	if (!sci_uart_driver.state) {
3147		ret = uart_register_driver(&sci_uart_driver);
3148		if (ret) {
3149			mutex_unlock(&sci_uart_registration_lock);
3150			return ret;
3151		}
3152	}
3153	mutex_unlock(&sci_uart_registration_lock);
3154
3155	ret = sci_init_single(dev, sciport, index, p, false);
3156	if (ret)
3157		return ret;
3158
3159	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3160	if (IS_ERR(sciport->gpios) && PTR_ERR(sciport->gpios) != -ENOSYS)
3161		return PTR_ERR(sciport->gpios);
3162
3163	if (sciport->has_rtscts) {
3164		if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3165							UART_GPIO_CTS)) ||
3166		    !IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3167							UART_GPIO_RTS))) {
3168			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3169			return -EINVAL;
3170		}
3171		sciport->port.flags |= UPF_HARD_FLOW;
3172	}
3173
3174	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3175	if (ret) {
3176		sci_cleanup_single(sciport);
3177		return ret;
3178	}
3179
3180	return 0;
3181}
3182
3183static int sci_probe(struct platform_device *dev)
3184{
3185	struct plat_sci_port *p;
3186	struct sci_port *sp;
3187	unsigned int dev_id;
3188	int ret;
3189
3190	/*
3191	 * If we've come here via earlyprintk initialization, head off to
3192	 * the special early probe. We don't have sufficient device state
3193	 * to make it beyond this yet.
3194	 */
3195	if (is_early_platform_device(dev))
3196		return sci_probe_earlyprintk(dev);
3197
3198	if (dev->dev.of_node) {
3199		p = sci_parse_dt(dev, &dev_id);
3200		if (p == NULL)
3201			return -EINVAL;
3202	} else {
3203		p = dev->dev.platform_data;
3204		if (p == NULL) {
3205			dev_err(&dev->dev, "no platform data supplied\n");
3206			return -EINVAL;
3207		}
3208
3209		dev_id = dev->id;
3210	}
3211
3212	sp = &sci_ports[dev_id];
3213	platform_set_drvdata(dev, sp);
3214
3215	ret = sci_probe_single(dev, dev_id, p, sp);
3216	if (ret)
3217		return ret;
3218
3219	if (sp->port.fifosize > 1) {
3220		ret = sysfs_create_file(&dev->dev.kobj,
3221				&dev_attr_rx_fifo_trigger.attr);
3222		if (ret)
3223			return ret;
3224	}
3225	if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3226	    sp->port.type == PORT_HSCIF) {
3227		ret = sysfs_create_file(&dev->dev.kobj,
3228				&dev_attr_rx_fifo_timeout.attr);
3229		if (ret) {
3230			if (sp->port.fifosize > 1) {
3231				sysfs_remove_file(&dev->dev.kobj,
3232					&dev_attr_rx_fifo_trigger.attr);
3233			}
3234			return ret;
3235		}
3236	}
3237
3238#ifdef CONFIG_SH_STANDARD_BIOS
3239	sh_bios_gdb_detach();
3240#endif
3241
 
3242	return 0;
3243}
3244
3245static __maybe_unused int sci_suspend(struct device *dev)
3246{
3247	struct sci_port *sport = dev_get_drvdata(dev);
3248
3249	if (sport)
3250		uart_suspend_port(&sci_uart_driver, &sport->port);
3251
3252	return 0;
3253}
3254
3255static __maybe_unused int sci_resume(struct device *dev)
3256{
3257	struct sci_port *sport = dev_get_drvdata(dev);
3258
3259	if (sport)
3260		uart_resume_port(&sci_uart_driver, &sport->port);
3261
3262	return 0;
3263}
3264
3265static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3266
3267static struct platform_driver sci_driver = {
3268	.probe		= sci_probe,
3269	.remove		= sci_remove,
3270	.driver		= {
3271		.name	= "sh-sci",
3272		.pm	= &sci_dev_pm_ops,
3273		.of_match_table = of_match_ptr(of_sci_match),
3274	},
3275};
3276
3277static int __init sci_init(void)
3278{
3279	pr_info("%s\n", banner);
3280
3281	return platform_driver_register(&sci_driver);
3282}
3283
3284static void __exit sci_exit(void)
3285{
3286	platform_driver_unregister(&sci_driver);
3287
3288	if (sci_uart_driver.state)
3289		uart_unregister_driver(&sci_uart_driver);
3290}
3291
3292#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
3293early_platform_init_buffer("earlyprintk", &sci_driver,
3294			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3295#endif
3296#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3297static struct plat_sci_port port_cfg __initdata;
3298
3299static int __init early_console_setup(struct earlycon_device *device,
3300				      int type)
3301{
3302	if (!device->port.membase)
3303		return -ENODEV;
3304
3305	device->port.serial_in = sci_serial_in;
3306	device->port.serial_out	= sci_serial_out;
3307	device->port.type = type;
3308	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3309	port_cfg.type = type;
3310	sci_ports[0].cfg = &port_cfg;
3311	sci_ports[0].params = sci_probe_regmap(&port_cfg);
3312	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3313	sci_serial_out(&sci_ports[0].port, SCSCR,
3314		       SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3315
3316	device->con->write = serial_console_write;
3317	return 0;
3318}
3319static int __init sci_early_console_setup(struct earlycon_device *device,
3320					  const char *opt)
3321{
3322	return early_console_setup(device, PORT_SCI);
3323}
3324static int __init scif_early_console_setup(struct earlycon_device *device,
3325					  const char *opt)
3326{
3327	return early_console_setup(device, PORT_SCIF);
3328}
 
 
 
 
 
 
3329static int __init scifa_early_console_setup(struct earlycon_device *device,
3330					  const char *opt)
3331{
3332	return early_console_setup(device, PORT_SCIFA);
3333}
3334static int __init scifb_early_console_setup(struct earlycon_device *device,
3335					  const char *opt)
3336{
3337	return early_console_setup(device, PORT_SCIFB);
3338}
3339static int __init hscif_early_console_setup(struct earlycon_device *device,
3340					  const char *opt)
3341{
3342	return early_console_setup(device, PORT_HSCIF);
3343}
3344
3345OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3346OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
 
3347OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3348OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3349OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3350#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3351
3352module_init(sci_init);
3353module_exit(sci_exit);
3354
3355MODULE_LICENSE("GPL");
3356MODULE_ALIAS("platform:sh-sci");
3357MODULE_AUTHOR("Paul Mundt");
3358MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");