xref: /openbmc/linux/drivers/tty/serial/sh-sci.c (revision 2359ccdd)
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 */
63 enum {
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 
79 enum 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 
103 struct plat_sci_reg {
104 	u8 offset, size;
105 };
106 
107 struct 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 
117 struct 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 
162 static struct sci_port sci_ports[SCI_NPORTS];
163 static struct uart_driver sci_uart_driver;
164 
165 static inline struct sci_port *
166 to_sci_port(struct uart_port *uart)
167 {
168 	return container_of(uart, struct sci_port, port);
169 }
170 
171 static 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  */
474 static 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 
488 static 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 
500 static 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 
516 static 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 
529 static 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 
541 static 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 
571 static 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 
586 static 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 
598 static 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 
612 static 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
632 static 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 
659 static 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 
673 static 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 
723 static 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 
740 static int sci_txroom(struct uart_port *port)
741 {
742 	return port->fifosize - sci_txfill(port);
743 }
744 
745 static 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 
766 static 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 
827 static 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 
896 static 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 
940 static 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 
969 static 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 
996 static 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 
1055 static 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 
1064 static 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 
1073 static 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 
1083 static 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 
1104 static DEVICE_ATTR(rx_fifo_trigger, 0644, rx_trigger_show, rx_trigger_store);
1105 
1106 static 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 
1122 static 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 
1150 static DEVICE_ATTR_RW(rx_fifo_timeout);
1151 
1152 
1153 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1154 static 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 */
1188 static 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 
1203 static 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 
1214 static 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 
1235 static 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 
1244 static 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 
1288 fail:
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 
1294 static 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 
1315 static 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 
1343 fail:
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 
1352 static 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 
1406 static 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 
1479 static 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 
1515 static 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 
1596 static 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 
1606 static 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 */
1615 static inline void sci_request_dma(struct uart_port *port)
1616 {
1617 }
1618 
1619 static 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 
1626 static 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 
1673 static 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 
1685 static 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 
1712 static 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 
1723 static 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 
1769 static 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 
1805 static 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 
1846 out_noirq:
1847 	while (--i >= 0)
1848 		free_irq(port->irqs[i], port);
1849 
1850 out_nomem:
1851 	while (--j >= 0)
1852 		kfree(port->irqstr[j]);
1853 
1854 	return ret;
1855 }
1856 
1857 static 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 
1885 static 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 
1893 static 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 
1920 static 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  */
1945 static 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 
1990 static 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 
2016 static void sci_enable_ms(struct uart_port *port)
2017 {
2018 	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2019 }
2020 
2021 static 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 
2052 static 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 
2070 static 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 
2105 static 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 
2132 static 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 */
2164 static 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 
2225 found:
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 
2231 static 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 
2266 static 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 
2371 done:
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 
2516 static 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 
2531 static 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 
2551 static 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 
2579 static 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 
2591 static 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 
2613 static 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 
2623 static 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 
2632 static 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 
2657 static 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 
2702 found:
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 
2714 static const struct sci_port_params *
2715 sci_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 
2755 static 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 
2868 static 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)
2875 static 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  */
2884 static 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 
2926 static 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 
2961 static 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 
2971 static struct console early_serial_console = {
2972 	.name           = "early_ttySC",
2973 	.write          = serial_console_write,
2974 	.flags          = CON_PRINTBUFFER,
2975 	.index		= -1,
2976 };
2977 
2978 static char early_serial_buf[32];
2979 
2980 static 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
3003 static 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 
3012 static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3013 
3014 static DEFINE_MUTEX(sci_uart_registration_lock);
3015 static 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 
3025 static 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 
3051 static 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 };
3088 MODULE_DEVICE_TABLE(of, of_sci_match);
3089 
3090 static 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 
3130 static 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 
3183 static 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 
3245 static __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 
3255 static __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 
3265 static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3266 
3267 static 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 
3277 static int __init sci_init(void)
3278 {
3279 	pr_info("%s\n", banner);
3280 
3281 	return platform_driver_register(&sci_driver);
3282 }
3283 
3284 static 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
3293 early_platform_init_buffer("earlyprintk", &sci_driver,
3294 			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3295 #endif
3296 #ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3297 static struct plat_sci_port port_cfg __initdata;
3298 
3299 static 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 }
3319 static int __init sci_early_console_setup(struct earlycon_device *device,
3320 					  const char *opt)
3321 {
3322 	return early_console_setup(device, PORT_SCI);
3323 }
3324 static int __init scif_early_console_setup(struct earlycon_device *device,
3325 					  const char *opt)
3326 {
3327 	return early_console_setup(device, PORT_SCIF);
3328 }
3329 static int __init scifa_early_console_setup(struct earlycon_device *device,
3330 					  const char *opt)
3331 {
3332 	return early_console_setup(device, PORT_SCIFA);
3333 }
3334 static int __init scifb_early_console_setup(struct earlycon_device *device,
3335 					  const char *opt)
3336 {
3337 	return early_console_setup(device, PORT_SCIFB);
3338 }
3339 static 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 
3345 OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3346 OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3347 OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3348 OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3349 OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3350 #endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3351 
3352 module_init(sci_init);
3353 module_exit(sci_exit);
3354 
3355 MODULE_LICENSE("GPL");
3356 MODULE_ALIAS("platform:sh-sci");
3357 MODULE_AUTHOR("Paul Mundt");
3358 MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
3359