xref: /openbmc/linux/drivers/tty/serial/sh-sci.c (revision b2765275)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SuperH on-chip serial module support.  (SCI with no FIFO / with FIFO)
4  *
5  *  Copyright (C) 2002 - 2011  Paul Mundt
6  *  Copyright (C) 2015 Glider bvba
7  *  Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
8  *
9  * based off of the old drivers/char/sh-sci.c by:
10  *
11  *   Copyright (C) 1999, 2000  Niibe Yutaka
12  *   Copyright (C) 2000  Sugioka Toshinobu
13  *   Modified to support multiple serial ports. Stuart Menefy (May 2000).
14  *   Modified to support SecureEdge. David McCullough (2002)
15  *   Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
16  *   Removed SH7300 support (Jul 2007).
17  */
18 #undef DEBUG
19 
20 #include <linux/clk.h>
21 #include <linux/console.h>
22 #include <linux/ctype.h>
23 #include <linux/cpufreq.h>
24 #include <linux/delay.h>
25 #include <linux/dmaengine.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/err.h>
28 #include <linux/errno.h>
29 #include <linux/init.h>
30 #include <linux/interrupt.h>
31 #include <linux/ioport.h>
32 #include <linux/ktime.h>
33 #include <linux/major.h>
34 #include <linux/module.h>
35 #include <linux/mm.h>
36 #include <linux/of.h>
37 #include <linux/of_device.h>
38 #include <linux/platform_device.h>
39 #include <linux/pm_runtime.h>
40 #include <linux/scatterlist.h>
41 #include <linux/serial.h>
42 #include <linux/serial_sci.h>
43 #include <linux/sh_dma.h>
44 #include <linux/slab.h>
45 #include <linux/string.h>
46 #include <linux/sysrq.h>
47 #include <linux/timer.h>
48 #include <linux/tty.h>
49 #include <linux/tty_flip.h>
50 
51 #ifdef CONFIG_SUPERH
52 #include <asm/sh_bios.h>
53 #include <asm/platform_early.h>
54 #endif
55 
56 #include "serial_mctrl_gpio.h"
57 #include "sh-sci.h"
58 
59 /* Offsets into the sci_port->irqs array */
60 enum {
61 	SCIx_ERI_IRQ,
62 	SCIx_RXI_IRQ,
63 	SCIx_TXI_IRQ,
64 	SCIx_BRI_IRQ,
65 	SCIx_DRI_IRQ,
66 	SCIx_TEI_IRQ,
67 	SCIx_NR_IRQS,
68 
69 	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
70 };
71 
72 #define SCIx_IRQ_IS_MUXED(port)			\
73 	((port)->irqs[SCIx_ERI_IRQ] ==	\
74 	 (port)->irqs[SCIx_RXI_IRQ]) ||	\
75 	((port)->irqs[SCIx_ERI_IRQ] &&	\
76 	 ((port)->irqs[SCIx_RXI_IRQ] < 0))
77 
78 enum SCI_CLKS {
79 	SCI_FCK,		/* Functional Clock */
80 	SCI_SCK,		/* Optional External Clock */
81 	SCI_BRG_INT,		/* Optional BRG Internal Clock Source */
82 	SCI_SCIF_CLK,		/* Optional BRG External Clock Source */
83 	SCI_NUM_CLKS
84 };
85 
86 /* Bit x set means sampling rate x + 1 is supported */
87 #define SCI_SR(x)		BIT((x) - 1)
88 #define SCI_SR_RANGE(x, y)	GENMASK((y) - 1, (x) - 1)
89 
90 #define SCI_SR_SCIFAB		SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
91 				SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
92 				SCI_SR(19) | SCI_SR(27)
93 
94 #define min_sr(_port)		ffs((_port)->sampling_rate_mask)
95 #define max_sr(_port)		fls((_port)->sampling_rate_mask)
96 
97 /* Iterate over all supported sampling rates, from high to low */
98 #define for_each_sr(_sr, _port)						\
99 	for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--)	\
100 		if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
101 
102 struct plat_sci_reg {
103 	u8 offset, size;
104 };
105 
106 struct sci_port_params {
107 	const struct plat_sci_reg regs[SCIx_NR_REGS];
108 	unsigned int fifosize;
109 	unsigned int overrun_reg;
110 	unsigned int overrun_mask;
111 	unsigned int sampling_rate_mask;
112 	unsigned int error_mask;
113 	unsigned int error_clear;
114 };
115 
116 struct sci_port {
117 	struct uart_port	port;
118 
119 	/* Platform configuration */
120 	const struct sci_port_params *params;
121 	const struct plat_sci_port *cfg;
122 	unsigned int		sampling_rate_mask;
123 	resource_size_t		reg_size;
124 	struct mctrl_gpios	*gpios;
125 
126 	/* Clocks */
127 	struct clk		*clks[SCI_NUM_CLKS];
128 	unsigned long		clk_rates[SCI_NUM_CLKS];
129 
130 	int			irqs[SCIx_NR_IRQS];
131 	char			*irqstr[SCIx_NR_IRQS];
132 
133 	struct dma_chan			*chan_tx;
134 	struct dma_chan			*chan_rx;
135 
136 #ifdef CONFIG_SERIAL_SH_SCI_DMA
137 	struct dma_chan			*chan_tx_saved;
138 	struct dma_chan			*chan_rx_saved;
139 	dma_cookie_t			cookie_tx;
140 	dma_cookie_t			cookie_rx[2];
141 	dma_cookie_t			active_rx;
142 	dma_addr_t			tx_dma_addr;
143 	unsigned int			tx_dma_len;
144 	struct scatterlist		sg_rx[2];
145 	void				*rx_buf[2];
146 	size_t				buf_len_rx;
147 	struct work_struct		work_tx;
148 	struct hrtimer			rx_timer;
149 	unsigned int			rx_timeout;	/* microseconds */
150 #endif
151 	unsigned int			rx_frame;
152 	int				rx_trigger;
153 	struct timer_list		rx_fifo_timer;
154 	int				rx_fifo_timeout;
155 	u16				hscif_tot;
156 
157 	bool has_rtscts;
158 	bool autorts;
159 };
160 
161 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
162 
163 static struct sci_port sci_ports[SCI_NPORTS];
164 static unsigned long sci_ports_in_use;
165 static struct uart_driver sci_uart_driver;
166 
167 static inline struct sci_port *
168 to_sci_port(struct uart_port *uart)
169 {
170 	return container_of(uart, struct sci_port, port);
171 }
172 
173 static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
174 	/*
175 	 * Common SCI definitions, dependent on the port's regshift
176 	 * value.
177 	 */
178 	[SCIx_SCI_REGTYPE] = {
179 		.regs = {
180 			[SCSMR]		= { 0x00,  8 },
181 			[SCBRR]		= { 0x01,  8 },
182 			[SCSCR]		= { 0x02,  8 },
183 			[SCxTDR]	= { 0x03,  8 },
184 			[SCxSR]		= { 0x04,  8 },
185 			[SCxRDR]	= { 0x05,  8 },
186 		},
187 		.fifosize = 1,
188 		.overrun_reg = SCxSR,
189 		.overrun_mask = SCI_ORER,
190 		.sampling_rate_mask = SCI_SR(32),
191 		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
192 		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
193 	},
194 
195 	/*
196 	 * Common definitions for legacy IrDA ports.
197 	 */
198 	[SCIx_IRDA_REGTYPE] = {
199 		.regs = {
200 			[SCSMR]		= { 0x00,  8 },
201 			[SCBRR]		= { 0x02,  8 },
202 			[SCSCR]		= { 0x04,  8 },
203 			[SCxTDR]	= { 0x06,  8 },
204 			[SCxSR]		= { 0x08, 16 },
205 			[SCxRDR]	= { 0x0a,  8 },
206 			[SCFCR]		= { 0x0c,  8 },
207 			[SCFDR]		= { 0x0e, 16 },
208 		},
209 		.fifosize = 1,
210 		.overrun_reg = SCxSR,
211 		.overrun_mask = SCI_ORER,
212 		.sampling_rate_mask = SCI_SR(32),
213 		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
214 		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
215 	},
216 
217 	/*
218 	 * Common SCIFA definitions.
219 	 */
220 	[SCIx_SCIFA_REGTYPE] = {
221 		.regs = {
222 			[SCSMR]		= { 0x00, 16 },
223 			[SCBRR]		= { 0x04,  8 },
224 			[SCSCR]		= { 0x08, 16 },
225 			[SCxTDR]	= { 0x20,  8 },
226 			[SCxSR]		= { 0x14, 16 },
227 			[SCxRDR]	= { 0x24,  8 },
228 			[SCFCR]		= { 0x18, 16 },
229 			[SCFDR]		= { 0x1c, 16 },
230 			[SCPCR]		= { 0x30, 16 },
231 			[SCPDR]		= { 0x34, 16 },
232 		},
233 		.fifosize = 64,
234 		.overrun_reg = SCxSR,
235 		.overrun_mask = SCIFA_ORER,
236 		.sampling_rate_mask = SCI_SR_SCIFAB,
237 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
238 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
239 	},
240 
241 	/*
242 	 * Common SCIFB definitions.
243 	 */
244 	[SCIx_SCIFB_REGTYPE] = {
245 		.regs = {
246 			[SCSMR]		= { 0x00, 16 },
247 			[SCBRR]		= { 0x04,  8 },
248 			[SCSCR]		= { 0x08, 16 },
249 			[SCxTDR]	= { 0x40,  8 },
250 			[SCxSR]		= { 0x14, 16 },
251 			[SCxRDR]	= { 0x60,  8 },
252 			[SCFCR]		= { 0x18, 16 },
253 			[SCTFDR]	= { 0x38, 16 },
254 			[SCRFDR]	= { 0x3c, 16 },
255 			[SCPCR]		= { 0x30, 16 },
256 			[SCPDR]		= { 0x34, 16 },
257 		},
258 		.fifosize = 256,
259 		.overrun_reg = SCxSR,
260 		.overrun_mask = SCIFA_ORER,
261 		.sampling_rate_mask = SCI_SR_SCIFAB,
262 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
263 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
264 	},
265 
266 	/*
267 	 * Common SH-2(A) SCIF definitions for ports with FIFO data
268 	 * count registers.
269 	 */
270 	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
271 		.regs = {
272 			[SCSMR]		= { 0x00, 16 },
273 			[SCBRR]		= { 0x04,  8 },
274 			[SCSCR]		= { 0x08, 16 },
275 			[SCxTDR]	= { 0x0c,  8 },
276 			[SCxSR]		= { 0x10, 16 },
277 			[SCxRDR]	= { 0x14,  8 },
278 			[SCFCR]		= { 0x18, 16 },
279 			[SCFDR]		= { 0x1c, 16 },
280 			[SCSPTR]	= { 0x20, 16 },
281 			[SCLSR]		= { 0x24, 16 },
282 		},
283 		.fifosize = 16,
284 		.overrun_reg = SCLSR,
285 		.overrun_mask = SCLSR_ORER,
286 		.sampling_rate_mask = SCI_SR(32),
287 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
288 		.error_clear = SCIF_ERROR_CLEAR,
289 	},
290 
291 	/*
292 	 * The "SCIFA" that is in RZ/T and RZ/A2.
293 	 * It looks like a normal SCIF with FIFO data, but with a
294 	 * compressed address space. Also, the break out of interrupts
295 	 * are different: ERI/BRI, RXI, TXI, TEI, DRI.
296 	 */
297 	[SCIx_RZ_SCIFA_REGTYPE] = {
298 		.regs = {
299 			[SCSMR]		= { 0x00, 16 },
300 			[SCBRR]		= { 0x02,  8 },
301 			[SCSCR]		= { 0x04, 16 },
302 			[SCxTDR]	= { 0x06,  8 },
303 			[SCxSR]		= { 0x08, 16 },
304 			[SCxRDR]	= { 0x0A,  8 },
305 			[SCFCR]		= { 0x0C, 16 },
306 			[SCFDR]		= { 0x0E, 16 },
307 			[SCSPTR]	= { 0x10, 16 },
308 			[SCLSR]		= { 0x12, 16 },
309 		},
310 		.fifosize = 16,
311 		.overrun_reg = SCLSR,
312 		.overrun_mask = SCLSR_ORER,
313 		.sampling_rate_mask = SCI_SR(32),
314 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
315 		.error_clear = SCIF_ERROR_CLEAR,
316 	},
317 
318 	/*
319 	 * Common SH-3 SCIF definitions.
320 	 */
321 	[SCIx_SH3_SCIF_REGTYPE] = {
322 		.regs = {
323 			[SCSMR]		= { 0x00,  8 },
324 			[SCBRR]		= { 0x02,  8 },
325 			[SCSCR]		= { 0x04,  8 },
326 			[SCxTDR]	= { 0x06,  8 },
327 			[SCxSR]		= { 0x08, 16 },
328 			[SCxRDR]	= { 0x0a,  8 },
329 			[SCFCR]		= { 0x0c,  8 },
330 			[SCFDR]		= { 0x0e, 16 },
331 		},
332 		.fifosize = 16,
333 		.overrun_reg = SCLSR,
334 		.overrun_mask = SCLSR_ORER,
335 		.sampling_rate_mask = SCI_SR(32),
336 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
337 		.error_clear = SCIF_ERROR_CLEAR,
338 	},
339 
340 	/*
341 	 * Common SH-4(A) SCIF(B) definitions.
342 	 */
343 	[SCIx_SH4_SCIF_REGTYPE] = {
344 		.regs = {
345 			[SCSMR]		= { 0x00, 16 },
346 			[SCBRR]		= { 0x04,  8 },
347 			[SCSCR]		= { 0x08, 16 },
348 			[SCxTDR]	= { 0x0c,  8 },
349 			[SCxSR]		= { 0x10, 16 },
350 			[SCxRDR]	= { 0x14,  8 },
351 			[SCFCR]		= { 0x18, 16 },
352 			[SCFDR]		= { 0x1c, 16 },
353 			[SCSPTR]	= { 0x20, 16 },
354 			[SCLSR]		= { 0x24, 16 },
355 		},
356 		.fifosize = 16,
357 		.overrun_reg = SCLSR,
358 		.overrun_mask = SCLSR_ORER,
359 		.sampling_rate_mask = SCI_SR(32),
360 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
361 		.error_clear = SCIF_ERROR_CLEAR,
362 	},
363 
364 	/*
365 	 * Common SCIF definitions for ports with a Baud Rate Generator for
366 	 * External Clock (BRG).
367 	 */
368 	[SCIx_SH4_SCIF_BRG_REGTYPE] = {
369 		.regs = {
370 			[SCSMR]		= { 0x00, 16 },
371 			[SCBRR]		= { 0x04,  8 },
372 			[SCSCR]		= { 0x08, 16 },
373 			[SCxTDR]	= { 0x0c,  8 },
374 			[SCxSR]		= { 0x10, 16 },
375 			[SCxRDR]	= { 0x14,  8 },
376 			[SCFCR]		= { 0x18, 16 },
377 			[SCFDR]		= { 0x1c, 16 },
378 			[SCSPTR]	= { 0x20, 16 },
379 			[SCLSR]		= { 0x24, 16 },
380 			[SCDL]		= { 0x30, 16 },
381 			[SCCKS]		= { 0x34, 16 },
382 		},
383 		.fifosize = 16,
384 		.overrun_reg = SCLSR,
385 		.overrun_mask = SCLSR_ORER,
386 		.sampling_rate_mask = SCI_SR(32),
387 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
388 		.error_clear = SCIF_ERROR_CLEAR,
389 	},
390 
391 	/*
392 	 * Common HSCIF definitions.
393 	 */
394 	[SCIx_HSCIF_REGTYPE] = {
395 		.regs = {
396 			[SCSMR]		= { 0x00, 16 },
397 			[SCBRR]		= { 0x04,  8 },
398 			[SCSCR]		= { 0x08, 16 },
399 			[SCxTDR]	= { 0x0c,  8 },
400 			[SCxSR]		= { 0x10, 16 },
401 			[SCxRDR]	= { 0x14,  8 },
402 			[SCFCR]		= { 0x18, 16 },
403 			[SCFDR]		= { 0x1c, 16 },
404 			[SCSPTR]	= { 0x20, 16 },
405 			[SCLSR]		= { 0x24, 16 },
406 			[HSSRR]		= { 0x40, 16 },
407 			[SCDL]		= { 0x30, 16 },
408 			[SCCKS]		= { 0x34, 16 },
409 			[HSRTRGR]	= { 0x54, 16 },
410 			[HSTTRGR]	= { 0x58, 16 },
411 		},
412 		.fifosize = 128,
413 		.overrun_reg = SCLSR,
414 		.overrun_mask = SCLSR_ORER,
415 		.sampling_rate_mask = SCI_SR_RANGE(8, 32),
416 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
417 		.error_clear = SCIF_ERROR_CLEAR,
418 	},
419 
420 	/*
421 	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
422 	 * register.
423 	 */
424 	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
425 		.regs = {
426 			[SCSMR]		= { 0x00, 16 },
427 			[SCBRR]		= { 0x04,  8 },
428 			[SCSCR]		= { 0x08, 16 },
429 			[SCxTDR]	= { 0x0c,  8 },
430 			[SCxSR]		= { 0x10, 16 },
431 			[SCxRDR]	= { 0x14,  8 },
432 			[SCFCR]		= { 0x18, 16 },
433 			[SCFDR]		= { 0x1c, 16 },
434 			[SCLSR]		= { 0x24, 16 },
435 		},
436 		.fifosize = 16,
437 		.overrun_reg = SCLSR,
438 		.overrun_mask = SCLSR_ORER,
439 		.sampling_rate_mask = SCI_SR(32),
440 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
441 		.error_clear = SCIF_ERROR_CLEAR,
442 	},
443 
444 	/*
445 	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
446 	 * count registers.
447 	 */
448 	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
449 		.regs = {
450 			[SCSMR]		= { 0x00, 16 },
451 			[SCBRR]		= { 0x04,  8 },
452 			[SCSCR]		= { 0x08, 16 },
453 			[SCxTDR]	= { 0x0c,  8 },
454 			[SCxSR]		= { 0x10, 16 },
455 			[SCxRDR]	= { 0x14,  8 },
456 			[SCFCR]		= { 0x18, 16 },
457 			[SCFDR]		= { 0x1c, 16 },
458 			[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
459 			[SCRFDR]	= { 0x20, 16 },
460 			[SCSPTR]	= { 0x24, 16 },
461 			[SCLSR]		= { 0x28, 16 },
462 		},
463 		.fifosize = 16,
464 		.overrun_reg = SCLSR,
465 		.overrun_mask = SCLSR_ORER,
466 		.sampling_rate_mask = SCI_SR(32),
467 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
468 		.error_clear = SCIF_ERROR_CLEAR,
469 	},
470 
471 	/*
472 	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
473 	 * registers.
474 	 */
475 	[SCIx_SH7705_SCIF_REGTYPE] = {
476 		.regs = {
477 			[SCSMR]		= { 0x00, 16 },
478 			[SCBRR]		= { 0x04,  8 },
479 			[SCSCR]		= { 0x08, 16 },
480 			[SCxTDR]	= { 0x20,  8 },
481 			[SCxSR]		= { 0x14, 16 },
482 			[SCxRDR]	= { 0x24,  8 },
483 			[SCFCR]		= { 0x18, 16 },
484 			[SCFDR]		= { 0x1c, 16 },
485 		},
486 		.fifosize = 64,
487 		.overrun_reg = SCxSR,
488 		.overrun_mask = SCIFA_ORER,
489 		.sampling_rate_mask = SCI_SR(16),
490 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
491 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
492 	},
493 };
494 
495 #define sci_getreg(up, offset)		(&to_sci_port(up)->params->regs[offset])
496 
497 /*
498  * The "offset" here is rather misleading, in that it refers to an enum
499  * value relative to the port mapping rather than the fixed offset
500  * itself, which needs to be manually retrieved from the platform's
501  * register map for the given port.
502  */
503 static unsigned int sci_serial_in(struct uart_port *p, int offset)
504 {
505 	const struct plat_sci_reg *reg = sci_getreg(p, offset);
506 
507 	if (reg->size == 8)
508 		return ioread8(p->membase + (reg->offset << p->regshift));
509 	else if (reg->size == 16)
510 		return ioread16(p->membase + (reg->offset << p->regshift));
511 	else
512 		WARN(1, "Invalid register access\n");
513 
514 	return 0;
515 }
516 
517 static void sci_serial_out(struct uart_port *p, int offset, int value)
518 {
519 	const struct plat_sci_reg *reg = sci_getreg(p, offset);
520 
521 	if (reg->size == 8)
522 		iowrite8(value, p->membase + (reg->offset << p->regshift));
523 	else if (reg->size == 16)
524 		iowrite16(value, p->membase + (reg->offset << p->regshift));
525 	else
526 		WARN(1, "Invalid register access\n");
527 }
528 
529 static void sci_port_enable(struct sci_port *sci_port)
530 {
531 	unsigned int i;
532 
533 	if (!sci_port->port.dev)
534 		return;
535 
536 	pm_runtime_get_sync(sci_port->port.dev);
537 
538 	for (i = 0; i < SCI_NUM_CLKS; i++) {
539 		clk_prepare_enable(sci_port->clks[i]);
540 		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
541 	}
542 	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
543 }
544 
545 static void sci_port_disable(struct sci_port *sci_port)
546 {
547 	unsigned int i;
548 
549 	if (!sci_port->port.dev)
550 		return;
551 
552 	for (i = SCI_NUM_CLKS; i-- > 0; )
553 		clk_disable_unprepare(sci_port->clks[i]);
554 
555 	pm_runtime_put_sync(sci_port->port.dev);
556 }
557 
558 static inline unsigned long port_rx_irq_mask(struct uart_port *port)
559 {
560 	/*
561 	 * Not all ports (such as SCIFA) will support REIE. Rather than
562 	 * special-casing the port type, we check the port initialization
563 	 * IRQ enable mask to see whether the IRQ is desired at all. If
564 	 * it's unset, it's logically inferred that there's no point in
565 	 * testing for it.
566 	 */
567 	return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
568 }
569 
570 static void sci_start_tx(struct uart_port *port)
571 {
572 	struct sci_port *s = to_sci_port(port);
573 	unsigned short ctrl;
574 
575 #ifdef CONFIG_SERIAL_SH_SCI_DMA
576 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
577 		u16 new, scr = serial_port_in(port, SCSCR);
578 		if (s->chan_tx)
579 			new = scr | SCSCR_TDRQE;
580 		else
581 			new = scr & ~SCSCR_TDRQE;
582 		if (new != scr)
583 			serial_port_out(port, SCSCR, new);
584 	}
585 
586 	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
587 	    dma_submit_error(s->cookie_tx)) {
588 		s->cookie_tx = 0;
589 		schedule_work(&s->work_tx);
590 	}
591 #endif
592 
593 	if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
594 		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
595 		ctrl = serial_port_in(port, SCSCR);
596 		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
597 	}
598 }
599 
600 static void sci_stop_tx(struct uart_port *port)
601 {
602 	unsigned short ctrl;
603 
604 	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
605 	ctrl = serial_port_in(port, SCSCR);
606 
607 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
608 		ctrl &= ~SCSCR_TDRQE;
609 
610 	ctrl &= ~SCSCR_TIE;
611 
612 	serial_port_out(port, SCSCR, ctrl);
613 }
614 
615 static void sci_start_rx(struct uart_port *port)
616 {
617 	unsigned short ctrl;
618 
619 	ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
620 
621 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
622 		ctrl &= ~SCSCR_RDRQE;
623 
624 	serial_port_out(port, SCSCR, ctrl);
625 }
626 
627 static void sci_stop_rx(struct uart_port *port)
628 {
629 	unsigned short ctrl;
630 
631 	ctrl = serial_port_in(port, SCSCR);
632 
633 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
634 		ctrl &= ~SCSCR_RDRQE;
635 
636 	ctrl &= ~port_rx_irq_mask(port);
637 
638 	serial_port_out(port, SCSCR, ctrl);
639 }
640 
641 static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
642 {
643 	if (port->type == PORT_SCI) {
644 		/* Just store the mask */
645 		serial_port_out(port, SCxSR, mask);
646 	} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
647 		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
648 		/* Only clear the status bits we want to clear */
649 		serial_port_out(port, SCxSR,
650 				serial_port_in(port, SCxSR) & mask);
651 	} else {
652 		/* Store the mask, clear parity/framing errors */
653 		serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
654 	}
655 }
656 
657 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
658     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
659 
660 #ifdef CONFIG_CONSOLE_POLL
661 static int sci_poll_get_char(struct uart_port *port)
662 {
663 	unsigned short status;
664 	int c;
665 
666 	do {
667 		status = serial_port_in(port, SCxSR);
668 		if (status & SCxSR_ERRORS(port)) {
669 			sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
670 			continue;
671 		}
672 		break;
673 	} while (1);
674 
675 	if (!(status & SCxSR_RDxF(port)))
676 		return NO_POLL_CHAR;
677 
678 	c = serial_port_in(port, SCxRDR);
679 
680 	/* Dummy read */
681 	serial_port_in(port, SCxSR);
682 	sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
683 
684 	return c;
685 }
686 #endif
687 
688 static void sci_poll_put_char(struct uart_port *port, unsigned char c)
689 {
690 	unsigned short status;
691 
692 	do {
693 		status = serial_port_in(port, SCxSR);
694 	} while (!(status & SCxSR_TDxE(port)));
695 
696 	serial_port_out(port, SCxTDR, c);
697 	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
698 }
699 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
700 	  CONFIG_SERIAL_SH_SCI_EARLYCON */
701 
702 static void sci_init_pins(struct uart_port *port, unsigned int cflag)
703 {
704 	struct sci_port *s = to_sci_port(port);
705 
706 	/*
707 	 * Use port-specific handler if provided.
708 	 */
709 	if (s->cfg->ops && s->cfg->ops->init_pins) {
710 		s->cfg->ops->init_pins(port, cflag);
711 		return;
712 	}
713 
714 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
715 		u16 data = serial_port_in(port, SCPDR);
716 		u16 ctrl = serial_port_in(port, SCPCR);
717 
718 		/* Enable RXD and TXD pin functions */
719 		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
720 		if (to_sci_port(port)->has_rtscts) {
721 			/* RTS# is output, active low, unless autorts */
722 			if (!(port->mctrl & TIOCM_RTS)) {
723 				ctrl |= SCPCR_RTSC;
724 				data |= SCPDR_RTSD;
725 			} else if (!s->autorts) {
726 				ctrl |= SCPCR_RTSC;
727 				data &= ~SCPDR_RTSD;
728 			} else {
729 				/* Enable RTS# pin function */
730 				ctrl &= ~SCPCR_RTSC;
731 			}
732 			/* Enable CTS# pin function */
733 			ctrl &= ~SCPCR_CTSC;
734 		}
735 		serial_port_out(port, SCPDR, data);
736 		serial_port_out(port, SCPCR, ctrl);
737 	} else if (sci_getreg(port, SCSPTR)->size) {
738 		u16 status = serial_port_in(port, SCSPTR);
739 
740 		/* RTS# is always output; and active low, unless autorts */
741 		status |= SCSPTR_RTSIO;
742 		if (!(port->mctrl & TIOCM_RTS))
743 			status |= SCSPTR_RTSDT;
744 		else if (!s->autorts)
745 			status &= ~SCSPTR_RTSDT;
746 		/* CTS# and SCK are inputs */
747 		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
748 		serial_port_out(port, SCSPTR, status);
749 	}
750 }
751 
752 static int sci_txfill(struct uart_port *port)
753 {
754 	struct sci_port *s = to_sci_port(port);
755 	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
756 	const struct plat_sci_reg *reg;
757 
758 	reg = sci_getreg(port, SCTFDR);
759 	if (reg->size)
760 		return serial_port_in(port, SCTFDR) & fifo_mask;
761 
762 	reg = sci_getreg(port, SCFDR);
763 	if (reg->size)
764 		return serial_port_in(port, SCFDR) >> 8;
765 
766 	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
767 }
768 
769 static int sci_txroom(struct uart_port *port)
770 {
771 	return port->fifosize - sci_txfill(port);
772 }
773 
774 static int sci_rxfill(struct uart_port *port)
775 {
776 	struct sci_port *s = to_sci_port(port);
777 	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
778 	const struct plat_sci_reg *reg;
779 
780 	reg = sci_getreg(port, SCRFDR);
781 	if (reg->size)
782 		return serial_port_in(port, SCRFDR) & fifo_mask;
783 
784 	reg = sci_getreg(port, SCFDR);
785 	if (reg->size)
786 		return serial_port_in(port, SCFDR) & fifo_mask;
787 
788 	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
789 }
790 
791 /* ********************************************************************** *
792  *                   the interrupt related routines                       *
793  * ********************************************************************** */
794 
795 static void sci_transmit_chars(struct uart_port *port)
796 {
797 	struct circ_buf *xmit = &port->state->xmit;
798 	unsigned int stopped = uart_tx_stopped(port);
799 	unsigned short status;
800 	unsigned short ctrl;
801 	int count;
802 
803 	status = serial_port_in(port, SCxSR);
804 	if (!(status & SCxSR_TDxE(port))) {
805 		ctrl = serial_port_in(port, SCSCR);
806 		if (uart_circ_empty(xmit))
807 			ctrl &= ~SCSCR_TIE;
808 		else
809 			ctrl |= SCSCR_TIE;
810 		serial_port_out(port, SCSCR, ctrl);
811 		return;
812 	}
813 
814 	count = sci_txroom(port);
815 
816 	do {
817 		unsigned char c;
818 
819 		if (port->x_char) {
820 			c = port->x_char;
821 			port->x_char = 0;
822 		} else if (!uart_circ_empty(xmit) && !stopped) {
823 			c = xmit->buf[xmit->tail];
824 			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
825 		} else {
826 			break;
827 		}
828 
829 		serial_port_out(port, SCxTDR, c);
830 
831 		port->icount.tx++;
832 	} while (--count > 0);
833 
834 	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
835 
836 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
837 		uart_write_wakeup(port);
838 	if (uart_circ_empty(xmit))
839 		sci_stop_tx(port);
840 
841 }
842 
843 /* On SH3, SCIF may read end-of-break as a space->mark char */
844 #define STEPFN(c)  ({int __c = (c); (((__c-1)|(__c)) == -1); })
845 
846 static void sci_receive_chars(struct uart_port *port)
847 {
848 	struct tty_port *tport = &port->state->port;
849 	int i, count, copied = 0;
850 	unsigned short status;
851 	unsigned char flag;
852 
853 	status = serial_port_in(port, SCxSR);
854 	if (!(status & SCxSR_RDxF(port)))
855 		return;
856 
857 	while (1) {
858 		/* Don't copy more bytes than there is room for in the buffer */
859 		count = tty_buffer_request_room(tport, sci_rxfill(port));
860 
861 		/* If for any reason we can't copy more data, we're done! */
862 		if (count == 0)
863 			break;
864 
865 		if (port->type == PORT_SCI) {
866 			char c = serial_port_in(port, SCxRDR);
867 			if (uart_handle_sysrq_char(port, c))
868 				count = 0;
869 			else
870 				tty_insert_flip_char(tport, c, TTY_NORMAL);
871 		} else {
872 			for (i = 0; i < count; i++) {
873 				char c = serial_port_in(port, SCxRDR);
874 
875 				status = serial_port_in(port, SCxSR);
876 				if (uart_handle_sysrq_char(port, c)) {
877 					count--; i--;
878 					continue;
879 				}
880 
881 				/* Store data and status */
882 				if (status & SCxSR_FER(port)) {
883 					flag = TTY_FRAME;
884 					port->icount.frame++;
885 					dev_notice(port->dev, "frame error\n");
886 				} else if (status & SCxSR_PER(port)) {
887 					flag = TTY_PARITY;
888 					port->icount.parity++;
889 					dev_notice(port->dev, "parity error\n");
890 				} else
891 					flag = TTY_NORMAL;
892 
893 				tty_insert_flip_char(tport, c, flag);
894 			}
895 		}
896 
897 		serial_port_in(port, SCxSR); /* dummy read */
898 		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
899 
900 		copied += count;
901 		port->icount.rx += count;
902 	}
903 
904 	if (copied) {
905 		/* Tell the rest of the system the news. New characters! */
906 		tty_flip_buffer_push(tport);
907 	} else {
908 		/* TTY buffers full; read from RX reg to prevent lockup */
909 		serial_port_in(port, SCxRDR);
910 		serial_port_in(port, SCxSR); /* dummy read */
911 		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
912 	}
913 }
914 
915 static int sci_handle_errors(struct uart_port *port)
916 {
917 	int copied = 0;
918 	unsigned short status = serial_port_in(port, SCxSR);
919 	struct tty_port *tport = &port->state->port;
920 	struct sci_port *s = to_sci_port(port);
921 
922 	/* Handle overruns */
923 	if (status & s->params->overrun_mask) {
924 		port->icount.overrun++;
925 
926 		/* overrun error */
927 		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
928 			copied++;
929 
930 		dev_notice(port->dev, "overrun error\n");
931 	}
932 
933 	if (status & SCxSR_FER(port)) {
934 		/* frame error */
935 		port->icount.frame++;
936 
937 		if (tty_insert_flip_char(tport, 0, TTY_FRAME))
938 			copied++;
939 
940 		dev_notice(port->dev, "frame error\n");
941 	}
942 
943 	if (status & SCxSR_PER(port)) {
944 		/* parity error */
945 		port->icount.parity++;
946 
947 		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
948 			copied++;
949 
950 		dev_notice(port->dev, "parity error\n");
951 	}
952 
953 	if (copied)
954 		tty_flip_buffer_push(tport);
955 
956 	return copied;
957 }
958 
959 static int sci_handle_fifo_overrun(struct uart_port *port)
960 {
961 	struct tty_port *tport = &port->state->port;
962 	struct sci_port *s = to_sci_port(port);
963 	const struct plat_sci_reg *reg;
964 	int copied = 0;
965 	u16 status;
966 
967 	reg = sci_getreg(port, s->params->overrun_reg);
968 	if (!reg->size)
969 		return 0;
970 
971 	status = serial_port_in(port, s->params->overrun_reg);
972 	if (status & s->params->overrun_mask) {
973 		status &= ~s->params->overrun_mask;
974 		serial_port_out(port, s->params->overrun_reg, status);
975 
976 		port->icount.overrun++;
977 
978 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
979 		tty_flip_buffer_push(tport);
980 
981 		dev_dbg(port->dev, "overrun error\n");
982 		copied++;
983 	}
984 
985 	return copied;
986 }
987 
988 static int sci_handle_breaks(struct uart_port *port)
989 {
990 	int copied = 0;
991 	unsigned short status = serial_port_in(port, SCxSR);
992 	struct tty_port *tport = &port->state->port;
993 
994 	if (uart_handle_break(port))
995 		return 0;
996 
997 	if (status & SCxSR_BRK(port)) {
998 		port->icount.brk++;
999 
1000 		/* Notify of BREAK */
1001 		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1002 			copied++;
1003 
1004 		dev_dbg(port->dev, "BREAK detected\n");
1005 	}
1006 
1007 	if (copied)
1008 		tty_flip_buffer_push(tport);
1009 
1010 	copied += sci_handle_fifo_overrun(port);
1011 
1012 	return copied;
1013 }
1014 
1015 static int scif_set_rtrg(struct uart_port *port, int rx_trig)
1016 {
1017 	unsigned int bits;
1018 
1019 	if (rx_trig < 1)
1020 		rx_trig = 1;
1021 	if (rx_trig >= port->fifosize)
1022 		rx_trig = port->fifosize;
1023 
1024 	/* HSCIF can be set to an arbitrary level. */
1025 	if (sci_getreg(port, HSRTRGR)->size) {
1026 		serial_port_out(port, HSRTRGR, rx_trig);
1027 		return rx_trig;
1028 	}
1029 
1030 	switch (port->type) {
1031 	case PORT_SCIF:
1032 		if (rx_trig < 4) {
1033 			bits = 0;
1034 			rx_trig = 1;
1035 		} else if (rx_trig < 8) {
1036 			bits = SCFCR_RTRG0;
1037 			rx_trig = 4;
1038 		} else if (rx_trig < 14) {
1039 			bits = SCFCR_RTRG1;
1040 			rx_trig = 8;
1041 		} else {
1042 			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1043 			rx_trig = 14;
1044 		}
1045 		break;
1046 	case PORT_SCIFA:
1047 	case PORT_SCIFB:
1048 		if (rx_trig < 16) {
1049 			bits = 0;
1050 			rx_trig = 1;
1051 		} else if (rx_trig < 32) {
1052 			bits = SCFCR_RTRG0;
1053 			rx_trig = 16;
1054 		} else if (rx_trig < 48) {
1055 			bits = SCFCR_RTRG1;
1056 			rx_trig = 32;
1057 		} else {
1058 			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1059 			rx_trig = 48;
1060 		}
1061 		break;
1062 	default:
1063 		WARN(1, "unknown FIFO configuration");
1064 		return 1;
1065 	}
1066 
1067 	serial_port_out(port, SCFCR,
1068 		(serial_port_in(port, SCFCR) &
1069 		~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1070 
1071 	return rx_trig;
1072 }
1073 
1074 static int scif_rtrg_enabled(struct uart_port *port)
1075 {
1076 	if (sci_getreg(port, HSRTRGR)->size)
1077 		return serial_port_in(port, HSRTRGR) != 0;
1078 	else
1079 		return (serial_port_in(port, SCFCR) &
1080 			(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1081 }
1082 
1083 static void rx_fifo_timer_fn(struct timer_list *t)
1084 {
1085 	struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1086 	struct uart_port *port = &s->port;
1087 
1088 	dev_dbg(port->dev, "Rx timed out\n");
1089 	scif_set_rtrg(port, 1);
1090 }
1091 
1092 static ssize_t rx_fifo_trigger_show(struct device *dev,
1093 				    struct device_attribute *attr, char *buf)
1094 {
1095 	struct uart_port *port = dev_get_drvdata(dev);
1096 	struct sci_port *sci = to_sci_port(port);
1097 
1098 	return sprintf(buf, "%d\n", sci->rx_trigger);
1099 }
1100 
1101 static ssize_t rx_fifo_trigger_store(struct device *dev,
1102 				     struct device_attribute *attr,
1103 				     const char *buf, size_t count)
1104 {
1105 	struct uart_port *port = dev_get_drvdata(dev);
1106 	struct sci_port *sci = to_sci_port(port);
1107 	int ret;
1108 	long r;
1109 
1110 	ret = kstrtol(buf, 0, &r);
1111 	if (ret)
1112 		return ret;
1113 
1114 	sci->rx_trigger = scif_set_rtrg(port, r);
1115 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1116 		scif_set_rtrg(port, 1);
1117 
1118 	return count;
1119 }
1120 
1121 static DEVICE_ATTR_RW(rx_fifo_trigger);
1122 
1123 static ssize_t rx_fifo_timeout_show(struct device *dev,
1124 			       struct device_attribute *attr,
1125 			       char *buf)
1126 {
1127 	struct uart_port *port = dev_get_drvdata(dev);
1128 	struct sci_port *sci = to_sci_port(port);
1129 	int v;
1130 
1131 	if (port->type == PORT_HSCIF)
1132 		v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1133 	else
1134 		v = sci->rx_fifo_timeout;
1135 
1136 	return sprintf(buf, "%d\n", v);
1137 }
1138 
1139 static ssize_t rx_fifo_timeout_store(struct device *dev,
1140 				struct device_attribute *attr,
1141 				const char *buf,
1142 				size_t count)
1143 {
1144 	struct uart_port *port = dev_get_drvdata(dev);
1145 	struct sci_port *sci = to_sci_port(port);
1146 	int ret;
1147 	long r;
1148 
1149 	ret = kstrtol(buf, 0, &r);
1150 	if (ret)
1151 		return ret;
1152 
1153 	if (port->type == PORT_HSCIF) {
1154 		if (r < 0 || r > 3)
1155 			return -EINVAL;
1156 		sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1157 	} else {
1158 		sci->rx_fifo_timeout = r;
1159 		scif_set_rtrg(port, 1);
1160 		if (r > 0)
1161 			timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1162 	}
1163 
1164 	return count;
1165 }
1166 
1167 static DEVICE_ATTR_RW(rx_fifo_timeout);
1168 
1169 
1170 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1171 static void sci_dma_tx_complete(void *arg)
1172 {
1173 	struct sci_port *s = arg;
1174 	struct uart_port *port = &s->port;
1175 	struct circ_buf *xmit = &port->state->xmit;
1176 	unsigned long flags;
1177 
1178 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1179 
1180 	spin_lock_irqsave(&port->lock, flags);
1181 
1182 	xmit->tail += s->tx_dma_len;
1183 	xmit->tail &= UART_XMIT_SIZE - 1;
1184 
1185 	port->icount.tx += s->tx_dma_len;
1186 
1187 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1188 		uart_write_wakeup(port);
1189 
1190 	if (!uart_circ_empty(xmit)) {
1191 		s->cookie_tx = 0;
1192 		schedule_work(&s->work_tx);
1193 	} else {
1194 		s->cookie_tx = -EINVAL;
1195 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1196 			u16 ctrl = serial_port_in(port, SCSCR);
1197 			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1198 		}
1199 	}
1200 
1201 	spin_unlock_irqrestore(&port->lock, flags);
1202 }
1203 
1204 /* Locking: called with port lock held */
1205 static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1206 {
1207 	struct uart_port *port = &s->port;
1208 	struct tty_port *tport = &port->state->port;
1209 	int copied;
1210 
1211 	copied = tty_insert_flip_string(tport, buf, count);
1212 	if (copied < count)
1213 		port->icount.buf_overrun++;
1214 
1215 	port->icount.rx += copied;
1216 
1217 	return copied;
1218 }
1219 
1220 static int sci_dma_rx_find_active(struct sci_port *s)
1221 {
1222 	unsigned int i;
1223 
1224 	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1225 		if (s->active_rx == s->cookie_rx[i])
1226 			return i;
1227 
1228 	return -1;
1229 }
1230 
1231 static void sci_dma_rx_chan_invalidate(struct sci_port *s)
1232 {
1233 	unsigned int i;
1234 
1235 	s->chan_rx = NULL;
1236 	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1237 		s->cookie_rx[i] = -EINVAL;
1238 	s->active_rx = 0;
1239 }
1240 
1241 static void sci_dma_rx_release(struct sci_port *s)
1242 {
1243 	struct dma_chan *chan = s->chan_rx_saved;
1244 
1245 	s->chan_rx_saved = NULL;
1246 	sci_dma_rx_chan_invalidate(s);
1247 	dmaengine_terminate_sync(chan);
1248 	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1249 			  sg_dma_address(&s->sg_rx[0]));
1250 	dma_release_channel(chan);
1251 }
1252 
1253 static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1254 {
1255 	long sec = usec / 1000000;
1256 	long nsec = (usec % 1000000) * 1000;
1257 	ktime_t t = ktime_set(sec, nsec);
1258 
1259 	hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1260 }
1261 
1262 static void sci_dma_rx_reenable_irq(struct sci_port *s)
1263 {
1264 	struct uart_port *port = &s->port;
1265 	u16 scr;
1266 
1267 	/* Direct new serial port interrupts back to CPU */
1268 	scr = serial_port_in(port, SCSCR);
1269 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1270 		scr &= ~SCSCR_RDRQE;
1271 		enable_irq(s->irqs[SCIx_RXI_IRQ]);
1272 	}
1273 	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1274 }
1275 
1276 static void sci_dma_rx_complete(void *arg)
1277 {
1278 	struct sci_port *s = arg;
1279 	struct dma_chan *chan = s->chan_rx;
1280 	struct uart_port *port = &s->port;
1281 	struct dma_async_tx_descriptor *desc;
1282 	unsigned long flags;
1283 	int active, count = 0;
1284 
1285 	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1286 		s->active_rx);
1287 
1288 	spin_lock_irqsave(&port->lock, flags);
1289 
1290 	active = sci_dma_rx_find_active(s);
1291 	if (active >= 0)
1292 		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1293 
1294 	start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1295 
1296 	if (count)
1297 		tty_flip_buffer_push(&port->state->port);
1298 
1299 	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1300 				       DMA_DEV_TO_MEM,
1301 				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1302 	if (!desc)
1303 		goto fail;
1304 
1305 	desc->callback = sci_dma_rx_complete;
1306 	desc->callback_param = s;
1307 	s->cookie_rx[active] = dmaengine_submit(desc);
1308 	if (dma_submit_error(s->cookie_rx[active]))
1309 		goto fail;
1310 
1311 	s->active_rx = s->cookie_rx[!active];
1312 
1313 	dma_async_issue_pending(chan);
1314 
1315 	spin_unlock_irqrestore(&port->lock, flags);
1316 	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1317 		__func__, s->cookie_rx[active], active, s->active_rx);
1318 	return;
1319 
1320 fail:
1321 	spin_unlock_irqrestore(&port->lock, flags);
1322 	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1323 	/* Switch to PIO */
1324 	spin_lock_irqsave(&port->lock, flags);
1325 	dmaengine_terminate_async(chan);
1326 	sci_dma_rx_chan_invalidate(s);
1327 	sci_dma_rx_reenable_irq(s);
1328 	spin_unlock_irqrestore(&port->lock, flags);
1329 }
1330 
1331 static void sci_dma_tx_release(struct sci_port *s)
1332 {
1333 	struct dma_chan *chan = s->chan_tx_saved;
1334 
1335 	cancel_work_sync(&s->work_tx);
1336 	s->chan_tx_saved = s->chan_tx = NULL;
1337 	s->cookie_tx = -EINVAL;
1338 	dmaengine_terminate_sync(chan);
1339 	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1340 			 DMA_TO_DEVICE);
1341 	dma_release_channel(chan);
1342 }
1343 
1344 static int sci_dma_rx_submit(struct sci_port *s, bool port_lock_held)
1345 {
1346 	struct dma_chan *chan = s->chan_rx;
1347 	struct uart_port *port = &s->port;
1348 	unsigned long flags;
1349 	int i;
1350 
1351 	for (i = 0; i < 2; i++) {
1352 		struct scatterlist *sg = &s->sg_rx[i];
1353 		struct dma_async_tx_descriptor *desc;
1354 
1355 		desc = dmaengine_prep_slave_sg(chan,
1356 			sg, 1, DMA_DEV_TO_MEM,
1357 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1358 		if (!desc)
1359 			goto fail;
1360 
1361 		desc->callback = sci_dma_rx_complete;
1362 		desc->callback_param = s;
1363 		s->cookie_rx[i] = dmaengine_submit(desc);
1364 		if (dma_submit_error(s->cookie_rx[i]))
1365 			goto fail;
1366 
1367 	}
1368 
1369 	s->active_rx = s->cookie_rx[0];
1370 
1371 	dma_async_issue_pending(chan);
1372 	return 0;
1373 
1374 fail:
1375 	/* Switch to PIO */
1376 	if (!port_lock_held)
1377 		spin_lock_irqsave(&port->lock, flags);
1378 	if (i)
1379 		dmaengine_terminate_async(chan);
1380 	sci_dma_rx_chan_invalidate(s);
1381 	sci_start_rx(port);
1382 	if (!port_lock_held)
1383 		spin_unlock_irqrestore(&port->lock, flags);
1384 	return -EAGAIN;
1385 }
1386 
1387 static void sci_dma_tx_work_fn(struct work_struct *work)
1388 {
1389 	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1390 	struct dma_async_tx_descriptor *desc;
1391 	struct dma_chan *chan = s->chan_tx;
1392 	struct uart_port *port = &s->port;
1393 	struct circ_buf *xmit = &port->state->xmit;
1394 	unsigned long flags;
1395 	dma_addr_t buf;
1396 	int head, tail;
1397 
1398 	/*
1399 	 * DMA is idle now.
1400 	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1401 	 * offsets and lengths. Since it is a circular buffer, we have to
1402 	 * transmit till the end, and then the rest. Take the port lock to get a
1403 	 * consistent xmit buffer state.
1404 	 */
1405 	spin_lock_irq(&port->lock);
1406 	head = xmit->head;
1407 	tail = xmit->tail;
1408 	buf = s->tx_dma_addr + (tail & (UART_XMIT_SIZE - 1));
1409 	s->tx_dma_len = min_t(unsigned int,
1410 		CIRC_CNT(head, tail, UART_XMIT_SIZE),
1411 		CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE));
1412 	if (!s->tx_dma_len) {
1413 		/* Transmit buffer has been flushed */
1414 		spin_unlock_irq(&port->lock);
1415 		return;
1416 	}
1417 
1418 	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1419 					   DMA_MEM_TO_DEV,
1420 					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1421 	if (!desc) {
1422 		spin_unlock_irq(&port->lock);
1423 		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1424 		goto switch_to_pio;
1425 	}
1426 
1427 	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1428 				   DMA_TO_DEVICE);
1429 
1430 	desc->callback = sci_dma_tx_complete;
1431 	desc->callback_param = s;
1432 	s->cookie_tx = dmaengine_submit(desc);
1433 	if (dma_submit_error(s->cookie_tx)) {
1434 		spin_unlock_irq(&port->lock);
1435 		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1436 		goto switch_to_pio;
1437 	}
1438 
1439 	spin_unlock_irq(&port->lock);
1440 	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1441 		__func__, xmit->buf, tail, head, s->cookie_tx);
1442 
1443 	dma_async_issue_pending(chan);
1444 	return;
1445 
1446 switch_to_pio:
1447 	spin_lock_irqsave(&port->lock, flags);
1448 	s->chan_tx = NULL;
1449 	sci_start_tx(port);
1450 	spin_unlock_irqrestore(&port->lock, flags);
1451 	return;
1452 }
1453 
1454 static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
1455 {
1456 	struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1457 	struct dma_chan *chan = s->chan_rx;
1458 	struct uart_port *port = &s->port;
1459 	struct dma_tx_state state;
1460 	enum dma_status status;
1461 	unsigned long flags;
1462 	unsigned int read;
1463 	int active, count;
1464 
1465 	dev_dbg(port->dev, "DMA Rx timed out\n");
1466 
1467 	spin_lock_irqsave(&port->lock, flags);
1468 
1469 	active = sci_dma_rx_find_active(s);
1470 	if (active < 0) {
1471 		spin_unlock_irqrestore(&port->lock, flags);
1472 		return HRTIMER_NORESTART;
1473 	}
1474 
1475 	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1476 	if (status == DMA_COMPLETE) {
1477 		spin_unlock_irqrestore(&port->lock, flags);
1478 		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1479 			s->active_rx, active);
1480 
1481 		/* Let packet complete handler take care of the packet */
1482 		return HRTIMER_NORESTART;
1483 	}
1484 
1485 	dmaengine_pause(chan);
1486 
1487 	/*
1488 	 * sometimes DMA transfer doesn't stop even if it is stopped and
1489 	 * data keeps on coming until transaction is complete so check
1490 	 * for DMA_COMPLETE again
1491 	 * Let packet complete handler take care of the packet
1492 	 */
1493 	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1494 	if (status == DMA_COMPLETE) {
1495 		spin_unlock_irqrestore(&port->lock, flags);
1496 		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1497 		return HRTIMER_NORESTART;
1498 	}
1499 
1500 	/* Handle incomplete DMA receive */
1501 	dmaengine_terminate_async(s->chan_rx);
1502 	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1503 
1504 	if (read) {
1505 		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1506 		if (count)
1507 			tty_flip_buffer_push(&port->state->port);
1508 	}
1509 
1510 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1511 		sci_dma_rx_submit(s, true);
1512 
1513 	sci_dma_rx_reenable_irq(s);
1514 
1515 	spin_unlock_irqrestore(&port->lock, flags);
1516 
1517 	return HRTIMER_NORESTART;
1518 }
1519 
1520 static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1521 					     enum dma_transfer_direction dir)
1522 {
1523 	struct dma_chan *chan;
1524 	struct dma_slave_config cfg;
1525 	int ret;
1526 
1527 	chan = dma_request_slave_channel(port->dev,
1528 					 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1529 	if (!chan) {
1530 		dev_dbg(port->dev, "dma_request_slave_channel failed\n");
1531 		return NULL;
1532 	}
1533 
1534 	memset(&cfg, 0, sizeof(cfg));
1535 	cfg.direction = dir;
1536 	if (dir == DMA_MEM_TO_DEV) {
1537 		cfg.dst_addr = port->mapbase +
1538 			(sci_getreg(port, SCxTDR)->offset << port->regshift);
1539 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1540 	} else {
1541 		cfg.src_addr = port->mapbase +
1542 			(sci_getreg(port, SCxRDR)->offset << port->regshift);
1543 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1544 	}
1545 
1546 	ret = dmaengine_slave_config(chan, &cfg);
1547 	if (ret) {
1548 		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1549 		dma_release_channel(chan);
1550 		return NULL;
1551 	}
1552 
1553 	return chan;
1554 }
1555 
1556 static void sci_request_dma(struct uart_port *port)
1557 {
1558 	struct sci_port *s = to_sci_port(port);
1559 	struct dma_chan *chan;
1560 
1561 	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1562 
1563 	/*
1564 	 * DMA on console may interfere with Kernel log messages which use
1565 	 * plain putchar(). So, simply don't use it with a console.
1566 	 */
1567 	if (uart_console(port))
1568 		return;
1569 
1570 	if (!port->dev->of_node)
1571 		return;
1572 
1573 	s->cookie_tx = -EINVAL;
1574 
1575 	/*
1576 	 * Don't request a dma channel if no channel was specified
1577 	 * in the device tree.
1578 	 */
1579 	if (!of_find_property(port->dev->of_node, "dmas", NULL))
1580 		return;
1581 
1582 	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1583 	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1584 	if (chan) {
1585 		/* UART circular tx buffer is an aligned page. */
1586 		s->tx_dma_addr = dma_map_single(chan->device->dev,
1587 						port->state->xmit.buf,
1588 						UART_XMIT_SIZE,
1589 						DMA_TO_DEVICE);
1590 		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1591 			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1592 			dma_release_channel(chan);
1593 		} else {
1594 			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1595 				__func__, UART_XMIT_SIZE,
1596 				port->state->xmit.buf, &s->tx_dma_addr);
1597 
1598 			INIT_WORK(&s->work_tx, sci_dma_tx_work_fn);
1599 			s->chan_tx_saved = s->chan_tx = chan;
1600 		}
1601 	}
1602 
1603 	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1604 	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1605 	if (chan) {
1606 		unsigned int i;
1607 		dma_addr_t dma;
1608 		void *buf;
1609 
1610 		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1611 		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1612 					 &dma, GFP_KERNEL);
1613 		if (!buf) {
1614 			dev_warn(port->dev,
1615 				 "Failed to allocate Rx dma buffer, using PIO\n");
1616 			dma_release_channel(chan);
1617 			return;
1618 		}
1619 
1620 		for (i = 0; i < 2; i++) {
1621 			struct scatterlist *sg = &s->sg_rx[i];
1622 
1623 			sg_init_table(sg, 1);
1624 			s->rx_buf[i] = buf;
1625 			sg_dma_address(sg) = dma;
1626 			sg_dma_len(sg) = s->buf_len_rx;
1627 
1628 			buf += s->buf_len_rx;
1629 			dma += s->buf_len_rx;
1630 		}
1631 
1632 		hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1633 		s->rx_timer.function = sci_dma_rx_timer_fn;
1634 
1635 		s->chan_rx_saved = s->chan_rx = chan;
1636 
1637 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1638 			sci_dma_rx_submit(s, false);
1639 	}
1640 }
1641 
1642 static void sci_free_dma(struct uart_port *port)
1643 {
1644 	struct sci_port *s = to_sci_port(port);
1645 
1646 	if (s->chan_tx_saved)
1647 		sci_dma_tx_release(s);
1648 	if (s->chan_rx_saved)
1649 		sci_dma_rx_release(s);
1650 }
1651 
1652 static void sci_flush_buffer(struct uart_port *port)
1653 {
1654 	struct sci_port *s = to_sci_port(port);
1655 
1656 	/*
1657 	 * In uart_flush_buffer(), the xmit circular buffer has just been
1658 	 * cleared, so we have to reset tx_dma_len accordingly, and stop any
1659 	 * pending transfers
1660 	 */
1661 	s->tx_dma_len = 0;
1662 	if (s->chan_tx) {
1663 		dmaengine_terminate_async(s->chan_tx);
1664 		s->cookie_tx = -EINVAL;
1665 	}
1666 }
1667 #else /* !CONFIG_SERIAL_SH_SCI_DMA */
1668 static inline void sci_request_dma(struct uart_port *port)
1669 {
1670 }
1671 
1672 static inline void sci_free_dma(struct uart_port *port)
1673 {
1674 }
1675 
1676 #define sci_flush_buffer	NULL
1677 #endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1678 
1679 static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1680 {
1681 	struct uart_port *port = ptr;
1682 	struct sci_port *s = to_sci_port(port);
1683 
1684 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1685 	if (s->chan_rx) {
1686 		u16 scr = serial_port_in(port, SCSCR);
1687 		u16 ssr = serial_port_in(port, SCxSR);
1688 
1689 		/* Disable future Rx interrupts */
1690 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1691 			disable_irq_nosync(irq);
1692 			scr |= SCSCR_RDRQE;
1693 		} else {
1694 			if (sci_dma_rx_submit(s, false) < 0)
1695 				goto handle_pio;
1696 
1697 			scr &= ~SCSCR_RIE;
1698 		}
1699 		serial_port_out(port, SCSCR, scr);
1700 		/* Clear current interrupt */
1701 		serial_port_out(port, SCxSR,
1702 				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1703 		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1704 			jiffies, s->rx_timeout);
1705 		start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1706 
1707 		return IRQ_HANDLED;
1708 	}
1709 
1710 handle_pio:
1711 #endif
1712 
1713 	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1714 		if (!scif_rtrg_enabled(port))
1715 			scif_set_rtrg(port, s->rx_trigger);
1716 
1717 		mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1718 			  s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1719 	}
1720 
1721 	/* I think sci_receive_chars has to be called irrespective
1722 	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1723 	 * to be disabled?
1724 	 */
1725 	sci_receive_chars(port);
1726 
1727 	return IRQ_HANDLED;
1728 }
1729 
1730 static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1731 {
1732 	struct uart_port *port = ptr;
1733 	unsigned long flags;
1734 
1735 	spin_lock_irqsave(&port->lock, flags);
1736 	sci_transmit_chars(port);
1737 	spin_unlock_irqrestore(&port->lock, flags);
1738 
1739 	return IRQ_HANDLED;
1740 }
1741 
1742 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1743 {
1744 	struct uart_port *port = ptr;
1745 
1746 	/* Handle BREAKs */
1747 	sci_handle_breaks(port);
1748 	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1749 
1750 	return IRQ_HANDLED;
1751 }
1752 
1753 static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1754 {
1755 	struct uart_port *port = ptr;
1756 	struct sci_port *s = to_sci_port(port);
1757 
1758 	if (s->irqs[SCIx_ERI_IRQ] == s->irqs[SCIx_BRI_IRQ]) {
1759 		/* Break and Error interrupts are muxed */
1760 		unsigned short ssr_status = serial_port_in(port, SCxSR);
1761 
1762 		/* Break Interrupt */
1763 		if (ssr_status & SCxSR_BRK(port))
1764 			sci_br_interrupt(irq, ptr);
1765 
1766 		/* Break only? */
1767 		if (!(ssr_status & SCxSR_ERRORS(port)))
1768 			return IRQ_HANDLED;
1769 	}
1770 
1771 	/* Handle errors */
1772 	if (port->type == PORT_SCI) {
1773 		if (sci_handle_errors(port)) {
1774 			/* discard character in rx buffer */
1775 			serial_port_in(port, SCxSR);
1776 			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1777 		}
1778 	} else {
1779 		sci_handle_fifo_overrun(port);
1780 		if (!s->chan_rx)
1781 			sci_receive_chars(port);
1782 	}
1783 
1784 	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1785 
1786 	/* Kick the transmission */
1787 	if (!s->chan_tx)
1788 		sci_tx_interrupt(irq, ptr);
1789 
1790 	return IRQ_HANDLED;
1791 }
1792 
1793 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1794 {
1795 	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1796 	struct uart_port *port = ptr;
1797 	struct sci_port *s = to_sci_port(port);
1798 	irqreturn_t ret = IRQ_NONE;
1799 
1800 	ssr_status = serial_port_in(port, SCxSR);
1801 	scr_status = serial_port_in(port, SCSCR);
1802 	if (s->params->overrun_reg == SCxSR)
1803 		orer_status = ssr_status;
1804 	else if (sci_getreg(port, s->params->overrun_reg)->size)
1805 		orer_status = serial_port_in(port, s->params->overrun_reg);
1806 
1807 	err_enabled = scr_status & port_rx_irq_mask(port);
1808 
1809 	/* Tx Interrupt */
1810 	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1811 	    !s->chan_tx)
1812 		ret = sci_tx_interrupt(irq, ptr);
1813 
1814 	/*
1815 	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1816 	 * DR flags
1817 	 */
1818 	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1819 	    (scr_status & SCSCR_RIE))
1820 		ret = sci_rx_interrupt(irq, ptr);
1821 
1822 	/* Error Interrupt */
1823 	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1824 		ret = sci_er_interrupt(irq, ptr);
1825 
1826 	/* Break Interrupt */
1827 	if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1828 		ret = sci_br_interrupt(irq, ptr);
1829 
1830 	/* Overrun Interrupt */
1831 	if (orer_status & s->params->overrun_mask) {
1832 		sci_handle_fifo_overrun(port);
1833 		ret = IRQ_HANDLED;
1834 	}
1835 
1836 	return ret;
1837 }
1838 
1839 static const struct sci_irq_desc {
1840 	const char	*desc;
1841 	irq_handler_t	handler;
1842 } sci_irq_desc[] = {
1843 	/*
1844 	 * Split out handlers, the default case.
1845 	 */
1846 	[SCIx_ERI_IRQ] = {
1847 		.desc = "rx err",
1848 		.handler = sci_er_interrupt,
1849 	},
1850 
1851 	[SCIx_RXI_IRQ] = {
1852 		.desc = "rx full",
1853 		.handler = sci_rx_interrupt,
1854 	},
1855 
1856 	[SCIx_TXI_IRQ] = {
1857 		.desc = "tx empty",
1858 		.handler = sci_tx_interrupt,
1859 	},
1860 
1861 	[SCIx_BRI_IRQ] = {
1862 		.desc = "break",
1863 		.handler = sci_br_interrupt,
1864 	},
1865 
1866 	[SCIx_DRI_IRQ] = {
1867 		.desc = "rx ready",
1868 		.handler = sci_rx_interrupt,
1869 	},
1870 
1871 	[SCIx_TEI_IRQ] = {
1872 		.desc = "tx end",
1873 		.handler = sci_tx_interrupt,
1874 	},
1875 
1876 	/*
1877 	 * Special muxed handler.
1878 	 */
1879 	[SCIx_MUX_IRQ] = {
1880 		.desc = "mux",
1881 		.handler = sci_mpxed_interrupt,
1882 	},
1883 };
1884 
1885 static int sci_request_irq(struct sci_port *port)
1886 {
1887 	struct uart_port *up = &port->port;
1888 	int i, j, w, ret = 0;
1889 
1890 	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1891 		const struct sci_irq_desc *desc;
1892 		int irq;
1893 
1894 		/* Check if already registered (muxed) */
1895 		for (w = 0; w < i; w++)
1896 			if (port->irqs[w] == port->irqs[i])
1897 				w = i + 1;
1898 		if (w > i)
1899 			continue;
1900 
1901 		if (SCIx_IRQ_IS_MUXED(port)) {
1902 			i = SCIx_MUX_IRQ;
1903 			irq = up->irq;
1904 		} else {
1905 			irq = port->irqs[i];
1906 
1907 			/*
1908 			 * Certain port types won't support all of the
1909 			 * available interrupt sources.
1910 			 */
1911 			if (unlikely(irq < 0))
1912 				continue;
1913 		}
1914 
1915 		desc = sci_irq_desc + i;
1916 		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1917 					    dev_name(up->dev), desc->desc);
1918 		if (!port->irqstr[j]) {
1919 			ret = -ENOMEM;
1920 			goto out_nomem;
1921 		}
1922 
1923 		ret = request_irq(irq, desc->handler, up->irqflags,
1924 				  port->irqstr[j], port);
1925 		if (unlikely(ret)) {
1926 			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1927 			goto out_noirq;
1928 		}
1929 	}
1930 
1931 	return 0;
1932 
1933 out_noirq:
1934 	while (--i >= 0)
1935 		free_irq(port->irqs[i], port);
1936 
1937 out_nomem:
1938 	while (--j >= 0)
1939 		kfree(port->irqstr[j]);
1940 
1941 	return ret;
1942 }
1943 
1944 static void sci_free_irq(struct sci_port *port)
1945 {
1946 	int i, j;
1947 
1948 	/*
1949 	 * Intentionally in reverse order so we iterate over the muxed
1950 	 * IRQ first.
1951 	 */
1952 	for (i = 0; i < SCIx_NR_IRQS; i++) {
1953 		int irq = port->irqs[i];
1954 
1955 		/*
1956 		 * Certain port types won't support all of the available
1957 		 * interrupt sources.
1958 		 */
1959 		if (unlikely(irq < 0))
1960 			continue;
1961 
1962 		/* Check if already freed (irq was muxed) */
1963 		for (j = 0; j < i; j++)
1964 			if (port->irqs[j] == irq)
1965 				j = i + 1;
1966 		if (j > i)
1967 			continue;
1968 
1969 		free_irq(port->irqs[i], port);
1970 		kfree(port->irqstr[i]);
1971 
1972 		if (SCIx_IRQ_IS_MUXED(port)) {
1973 			/* If there's only one IRQ, we're done. */
1974 			return;
1975 		}
1976 	}
1977 }
1978 
1979 static unsigned int sci_tx_empty(struct uart_port *port)
1980 {
1981 	unsigned short status = serial_port_in(port, SCxSR);
1982 	unsigned short in_tx_fifo = sci_txfill(port);
1983 
1984 	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1985 }
1986 
1987 static void sci_set_rts(struct uart_port *port, bool state)
1988 {
1989 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1990 		u16 data = serial_port_in(port, SCPDR);
1991 
1992 		/* Active low */
1993 		if (state)
1994 			data &= ~SCPDR_RTSD;
1995 		else
1996 			data |= SCPDR_RTSD;
1997 		serial_port_out(port, SCPDR, data);
1998 
1999 		/* RTS# is output */
2000 		serial_port_out(port, SCPCR,
2001 				serial_port_in(port, SCPCR) | SCPCR_RTSC);
2002 	} else if (sci_getreg(port, SCSPTR)->size) {
2003 		u16 ctrl = serial_port_in(port, SCSPTR);
2004 
2005 		/* Active low */
2006 		if (state)
2007 			ctrl &= ~SCSPTR_RTSDT;
2008 		else
2009 			ctrl |= SCSPTR_RTSDT;
2010 		serial_port_out(port, SCSPTR, ctrl);
2011 	}
2012 }
2013 
2014 static bool sci_get_cts(struct uart_port *port)
2015 {
2016 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2017 		/* Active low */
2018 		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
2019 	} else if (sci_getreg(port, SCSPTR)->size) {
2020 		/* Active low */
2021 		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
2022 	}
2023 
2024 	return true;
2025 }
2026 
2027 /*
2028  * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
2029  * CTS/RTS is supported in hardware by at least one port and controlled
2030  * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
2031  * handled via the ->init_pins() op, which is a bit of a one-way street,
2032  * lacking any ability to defer pin control -- this will later be
2033  * converted over to the GPIO framework).
2034  *
2035  * Other modes (such as loopback) are supported generically on certain
2036  * port types, but not others. For these it's sufficient to test for the
2037  * existence of the support register and simply ignore the port type.
2038  */
2039 static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
2040 {
2041 	struct sci_port *s = to_sci_port(port);
2042 
2043 	if (mctrl & TIOCM_LOOP) {
2044 		const struct plat_sci_reg *reg;
2045 
2046 		/*
2047 		 * Standard loopback mode for SCFCR ports.
2048 		 */
2049 		reg = sci_getreg(port, SCFCR);
2050 		if (reg->size)
2051 			serial_port_out(port, SCFCR,
2052 					serial_port_in(port, SCFCR) |
2053 					SCFCR_LOOP);
2054 	}
2055 
2056 	mctrl_gpio_set(s->gpios, mctrl);
2057 
2058 	if (!s->has_rtscts)
2059 		return;
2060 
2061 	if (!(mctrl & TIOCM_RTS)) {
2062 		/* Disable Auto RTS */
2063 		serial_port_out(port, SCFCR,
2064 				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
2065 
2066 		/* Clear RTS */
2067 		sci_set_rts(port, 0);
2068 	} else if (s->autorts) {
2069 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2070 			/* Enable RTS# pin function */
2071 			serial_port_out(port, SCPCR,
2072 				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
2073 		}
2074 
2075 		/* Enable Auto RTS */
2076 		serial_port_out(port, SCFCR,
2077 				serial_port_in(port, SCFCR) | SCFCR_MCE);
2078 	} else {
2079 		/* Set RTS */
2080 		sci_set_rts(port, 1);
2081 	}
2082 }
2083 
2084 static unsigned int sci_get_mctrl(struct uart_port *port)
2085 {
2086 	struct sci_port *s = to_sci_port(port);
2087 	struct mctrl_gpios *gpios = s->gpios;
2088 	unsigned int mctrl = 0;
2089 
2090 	mctrl_gpio_get(gpios, &mctrl);
2091 
2092 	/*
2093 	 * CTS/RTS is handled in hardware when supported, while nothing
2094 	 * else is wired up.
2095 	 */
2096 	if (s->autorts) {
2097 		if (sci_get_cts(port))
2098 			mctrl |= TIOCM_CTS;
2099 	} else if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS)) {
2100 		mctrl |= TIOCM_CTS;
2101 	}
2102 	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR))
2103 		mctrl |= TIOCM_DSR;
2104 	if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD))
2105 		mctrl |= TIOCM_CAR;
2106 
2107 	return mctrl;
2108 }
2109 
2110 static void sci_enable_ms(struct uart_port *port)
2111 {
2112 	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2113 }
2114 
2115 static void sci_break_ctl(struct uart_port *port, int break_state)
2116 {
2117 	unsigned short scscr, scsptr;
2118 	unsigned long flags;
2119 
2120 	/* check wheter the port has SCSPTR */
2121 	if (!sci_getreg(port, SCSPTR)->size) {
2122 		/*
2123 		 * Not supported by hardware. Most parts couple break and rx
2124 		 * interrupts together, with break detection always enabled.
2125 		 */
2126 		return;
2127 	}
2128 
2129 	spin_lock_irqsave(&port->lock, flags);
2130 	scsptr = serial_port_in(port, SCSPTR);
2131 	scscr = serial_port_in(port, SCSCR);
2132 
2133 	if (break_state == -1) {
2134 		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2135 		scscr &= ~SCSCR_TE;
2136 	} else {
2137 		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2138 		scscr |= SCSCR_TE;
2139 	}
2140 
2141 	serial_port_out(port, SCSPTR, scsptr);
2142 	serial_port_out(port, SCSCR, scscr);
2143 	spin_unlock_irqrestore(&port->lock, flags);
2144 }
2145 
2146 static int sci_startup(struct uart_port *port)
2147 {
2148 	struct sci_port *s = to_sci_port(port);
2149 	int ret;
2150 
2151 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2152 
2153 	sci_request_dma(port);
2154 
2155 	ret = sci_request_irq(s);
2156 	if (unlikely(ret < 0)) {
2157 		sci_free_dma(port);
2158 		return ret;
2159 	}
2160 
2161 	return 0;
2162 }
2163 
2164 static void sci_shutdown(struct uart_port *port)
2165 {
2166 	struct sci_port *s = to_sci_port(port);
2167 	unsigned long flags;
2168 	u16 scr;
2169 
2170 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2171 
2172 	s->autorts = false;
2173 	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2174 
2175 	spin_lock_irqsave(&port->lock, flags);
2176 	sci_stop_rx(port);
2177 	sci_stop_tx(port);
2178 	/*
2179 	 * Stop RX and TX, disable related interrupts, keep clock source
2180 	 * and HSCIF TOT bits
2181 	 */
2182 	scr = serial_port_in(port, SCSCR);
2183 	serial_port_out(port, SCSCR, scr &
2184 			(SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2185 	spin_unlock_irqrestore(&port->lock, flags);
2186 
2187 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2188 	if (s->chan_rx_saved) {
2189 		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2190 			port->line);
2191 		hrtimer_cancel(&s->rx_timer);
2192 	}
2193 #endif
2194 
2195 	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
2196 		del_timer_sync(&s->rx_fifo_timer);
2197 	sci_free_irq(s);
2198 	sci_free_dma(port);
2199 }
2200 
2201 static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2202 			unsigned int *srr)
2203 {
2204 	unsigned long freq = s->clk_rates[SCI_SCK];
2205 	int err, min_err = INT_MAX;
2206 	unsigned int sr;
2207 
2208 	if (s->port.type != PORT_HSCIF)
2209 		freq *= 2;
2210 
2211 	for_each_sr(sr, s) {
2212 		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2213 		if (abs(err) >= abs(min_err))
2214 			continue;
2215 
2216 		min_err = err;
2217 		*srr = sr - 1;
2218 
2219 		if (!err)
2220 			break;
2221 	}
2222 
2223 	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2224 		*srr + 1);
2225 	return min_err;
2226 }
2227 
2228 static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2229 			unsigned long freq, unsigned int *dlr,
2230 			unsigned int *srr)
2231 {
2232 	int err, min_err = INT_MAX;
2233 	unsigned int sr, dl;
2234 
2235 	if (s->port.type != PORT_HSCIF)
2236 		freq *= 2;
2237 
2238 	for_each_sr(sr, s) {
2239 		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2240 		dl = clamp(dl, 1U, 65535U);
2241 
2242 		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2243 		if (abs(err) >= abs(min_err))
2244 			continue;
2245 
2246 		min_err = err;
2247 		*dlr = dl;
2248 		*srr = sr - 1;
2249 
2250 		if (!err)
2251 			break;
2252 	}
2253 
2254 	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2255 		min_err, *dlr, *srr + 1);
2256 	return min_err;
2257 }
2258 
2259 /* calculate sample rate, BRR, and clock select */
2260 static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2261 			  unsigned int *brr, unsigned int *srr,
2262 			  unsigned int *cks)
2263 {
2264 	unsigned long freq = s->clk_rates[SCI_FCK];
2265 	unsigned int sr, br, prediv, scrate, c;
2266 	int err, min_err = INT_MAX;
2267 
2268 	if (s->port.type != PORT_HSCIF)
2269 		freq *= 2;
2270 
2271 	/*
2272 	 * Find the combination of sample rate and clock select with the
2273 	 * smallest deviation from the desired baud rate.
2274 	 * Prefer high sample rates to maximise the receive margin.
2275 	 *
2276 	 * M: Receive margin (%)
2277 	 * N: Ratio of bit rate to clock (N = sampling rate)
2278 	 * D: Clock duty (D = 0 to 1.0)
2279 	 * L: Frame length (L = 9 to 12)
2280 	 * F: Absolute value of clock frequency deviation
2281 	 *
2282 	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2283 	 *      (|D - 0.5| / N * (1 + F))|
2284 	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2285 	 */
2286 	for_each_sr(sr, s) {
2287 		for (c = 0; c <= 3; c++) {
2288 			/* integerized formulas from HSCIF documentation */
2289 			prediv = sr * (1 << (2 * c + 1));
2290 
2291 			/*
2292 			 * We need to calculate:
2293 			 *
2294 			 *     br = freq / (prediv * bps) clamped to [1..256]
2295 			 *     err = freq / (br * prediv) - bps
2296 			 *
2297 			 * Watch out for overflow when calculating the desired
2298 			 * sampling clock rate!
2299 			 */
2300 			if (bps > UINT_MAX / prediv)
2301 				break;
2302 
2303 			scrate = prediv * bps;
2304 			br = DIV_ROUND_CLOSEST(freq, scrate);
2305 			br = clamp(br, 1U, 256U);
2306 
2307 			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2308 			if (abs(err) >= abs(min_err))
2309 				continue;
2310 
2311 			min_err = err;
2312 			*brr = br - 1;
2313 			*srr = sr - 1;
2314 			*cks = c;
2315 
2316 			if (!err)
2317 				goto found;
2318 		}
2319 	}
2320 
2321 found:
2322 	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2323 		min_err, *brr, *srr + 1, *cks);
2324 	return min_err;
2325 }
2326 
2327 static void sci_reset(struct uart_port *port)
2328 {
2329 	const struct plat_sci_reg *reg;
2330 	unsigned int status;
2331 	struct sci_port *s = to_sci_port(port);
2332 
2333 	serial_port_out(port, SCSCR, s->hscif_tot);	/* TE=0, RE=0, CKE1=0 */
2334 
2335 	reg = sci_getreg(port, SCFCR);
2336 	if (reg->size)
2337 		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2338 
2339 	sci_clear_SCxSR(port,
2340 			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2341 			SCxSR_BREAK_CLEAR(port));
2342 	if (sci_getreg(port, SCLSR)->size) {
2343 		status = serial_port_in(port, SCLSR);
2344 		status &= ~(SCLSR_TO | SCLSR_ORER);
2345 		serial_port_out(port, SCLSR, status);
2346 	}
2347 
2348 	if (s->rx_trigger > 1) {
2349 		if (s->rx_fifo_timeout) {
2350 			scif_set_rtrg(port, 1);
2351 			timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2352 		} else {
2353 			if (port->type == PORT_SCIFA ||
2354 			    port->type == PORT_SCIFB)
2355 				scif_set_rtrg(port, 1);
2356 			else
2357 				scif_set_rtrg(port, s->rx_trigger);
2358 		}
2359 	}
2360 }
2361 
2362 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2363 			    struct ktermios *old)
2364 {
2365 	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2366 	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2367 	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2368 	struct sci_port *s = to_sci_port(port);
2369 	const struct plat_sci_reg *reg;
2370 	int min_err = INT_MAX, err;
2371 	unsigned long max_freq = 0;
2372 	int best_clk = -1;
2373 	unsigned long flags;
2374 
2375 	if ((termios->c_cflag & CSIZE) == CS7)
2376 		smr_val |= SCSMR_CHR;
2377 	if (termios->c_cflag & PARENB)
2378 		smr_val |= SCSMR_PE;
2379 	if (termios->c_cflag & PARODD)
2380 		smr_val |= SCSMR_PE | SCSMR_ODD;
2381 	if (termios->c_cflag & CSTOPB)
2382 		smr_val |= SCSMR_STOP;
2383 
2384 	/*
2385 	 * earlyprintk comes here early on with port->uartclk set to zero.
2386 	 * the clock framework is not up and running at this point so here
2387 	 * we assume that 115200 is the maximum baud rate. please note that
2388 	 * the baud rate is not programmed during earlyprintk - it is assumed
2389 	 * that the previous boot loader has enabled required clocks and
2390 	 * setup the baud rate generator hardware for us already.
2391 	 */
2392 	if (!port->uartclk) {
2393 		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2394 		goto done;
2395 	}
2396 
2397 	for (i = 0; i < SCI_NUM_CLKS; i++)
2398 		max_freq = max(max_freq, s->clk_rates[i]);
2399 
2400 	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2401 	if (!baud)
2402 		goto done;
2403 
2404 	/*
2405 	 * There can be multiple sources for the sampling clock.  Find the one
2406 	 * that gives us the smallest deviation from the desired baud rate.
2407 	 */
2408 
2409 	/* Optional Undivided External Clock */
2410 	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2411 	    port->type != PORT_SCIFB) {
2412 		err = sci_sck_calc(s, baud, &srr1);
2413 		if (abs(err) < abs(min_err)) {
2414 			best_clk = SCI_SCK;
2415 			scr_val = SCSCR_CKE1;
2416 			sccks = SCCKS_CKS;
2417 			min_err = err;
2418 			srr = srr1;
2419 			if (!err)
2420 				goto done;
2421 		}
2422 	}
2423 
2424 	/* Optional BRG Frequency Divided External Clock */
2425 	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2426 		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2427 				   &srr1);
2428 		if (abs(err) < abs(min_err)) {
2429 			best_clk = SCI_SCIF_CLK;
2430 			scr_val = SCSCR_CKE1;
2431 			sccks = 0;
2432 			min_err = err;
2433 			dl = dl1;
2434 			srr = srr1;
2435 			if (!err)
2436 				goto done;
2437 		}
2438 	}
2439 
2440 	/* Optional BRG Frequency Divided Internal Clock */
2441 	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2442 		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2443 				   &srr1);
2444 		if (abs(err) < abs(min_err)) {
2445 			best_clk = SCI_BRG_INT;
2446 			scr_val = SCSCR_CKE1;
2447 			sccks = SCCKS_XIN;
2448 			min_err = err;
2449 			dl = dl1;
2450 			srr = srr1;
2451 			if (!min_err)
2452 				goto done;
2453 		}
2454 	}
2455 
2456 	/* Divided Functional Clock using standard Bit Rate Register */
2457 	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2458 	if (abs(err) < abs(min_err)) {
2459 		best_clk = SCI_FCK;
2460 		scr_val = 0;
2461 		min_err = err;
2462 		brr = brr1;
2463 		srr = srr1;
2464 		cks = cks1;
2465 	}
2466 
2467 done:
2468 	if (best_clk >= 0)
2469 		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2470 			s->clks[best_clk], baud, min_err);
2471 
2472 	sci_port_enable(s);
2473 
2474 	/*
2475 	 * Program the optional External Baud Rate Generator (BRG) first.
2476 	 * It controls the mux to select (H)SCK or frequency divided clock.
2477 	 */
2478 	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2479 		serial_port_out(port, SCDL, dl);
2480 		serial_port_out(port, SCCKS, sccks);
2481 	}
2482 
2483 	spin_lock_irqsave(&port->lock, flags);
2484 
2485 	sci_reset(port);
2486 
2487 	uart_update_timeout(port, termios->c_cflag, baud);
2488 
2489 	/* byte size and parity */
2490 	switch (termios->c_cflag & CSIZE) {
2491 	case CS5:
2492 		bits = 7;
2493 		break;
2494 	case CS6:
2495 		bits = 8;
2496 		break;
2497 	case CS7:
2498 		bits = 9;
2499 		break;
2500 	default:
2501 		bits = 10;
2502 		break;
2503 	}
2504 
2505 	if (termios->c_cflag & CSTOPB)
2506 		bits++;
2507 	if (termios->c_cflag & PARENB)
2508 		bits++;
2509 
2510 	if (best_clk >= 0) {
2511 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2512 			switch (srr + 1) {
2513 			case 5:  smr_val |= SCSMR_SRC_5;  break;
2514 			case 7:  smr_val |= SCSMR_SRC_7;  break;
2515 			case 11: smr_val |= SCSMR_SRC_11; break;
2516 			case 13: smr_val |= SCSMR_SRC_13; break;
2517 			case 16: smr_val |= SCSMR_SRC_16; break;
2518 			case 17: smr_val |= SCSMR_SRC_17; break;
2519 			case 19: smr_val |= SCSMR_SRC_19; break;
2520 			case 27: smr_val |= SCSMR_SRC_27; break;
2521 			}
2522 		smr_val |= cks;
2523 		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2524 		serial_port_out(port, SCSMR, smr_val);
2525 		serial_port_out(port, SCBRR, brr);
2526 		if (sci_getreg(port, HSSRR)->size) {
2527 			unsigned int hssrr = srr | HSCIF_SRE;
2528 			/* Calculate deviation from intended rate at the
2529 			 * center of the last stop bit in sampling clocks.
2530 			 */
2531 			int last_stop = bits * 2 - 1;
2532 			int deviation = DIV_ROUND_CLOSEST(min_err * last_stop *
2533 							  (int)(srr + 1),
2534 							  2 * (int)baud);
2535 
2536 			if (abs(deviation) >= 2) {
2537 				/* At least two sampling clocks off at the
2538 				 * last stop bit; we can increase the error
2539 				 * margin by shifting the sampling point.
2540 				 */
2541 				int shift = clamp(deviation / 2, -8, 7);
2542 
2543 				hssrr |= (shift << HSCIF_SRHP_SHIFT) &
2544 					 HSCIF_SRHP_MASK;
2545 				hssrr |= HSCIF_SRDE;
2546 			}
2547 			serial_port_out(port, HSSRR, hssrr);
2548 		}
2549 
2550 		/* Wait one bit interval */
2551 		udelay((1000000 + (baud - 1)) / baud);
2552 	} else {
2553 		/* Don't touch the bit rate configuration */
2554 		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2555 		smr_val |= serial_port_in(port, SCSMR) &
2556 			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2557 		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2558 		serial_port_out(port, SCSMR, smr_val);
2559 	}
2560 
2561 	sci_init_pins(port, termios->c_cflag);
2562 
2563 	port->status &= ~UPSTAT_AUTOCTS;
2564 	s->autorts = false;
2565 	reg = sci_getreg(port, SCFCR);
2566 	if (reg->size) {
2567 		unsigned short ctrl = serial_port_in(port, SCFCR);
2568 
2569 		if ((port->flags & UPF_HARD_FLOW) &&
2570 		    (termios->c_cflag & CRTSCTS)) {
2571 			/* There is no CTS interrupt to restart the hardware */
2572 			port->status |= UPSTAT_AUTOCTS;
2573 			/* MCE is enabled when RTS is raised */
2574 			s->autorts = true;
2575 		}
2576 
2577 		/*
2578 		 * As we've done a sci_reset() above, ensure we don't
2579 		 * interfere with the FIFOs while toggling MCE. As the
2580 		 * reset values could still be set, simply mask them out.
2581 		 */
2582 		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2583 
2584 		serial_port_out(port, SCFCR, ctrl);
2585 	}
2586 	if (port->flags & UPF_HARD_FLOW) {
2587 		/* Refresh (Auto) RTS */
2588 		sci_set_mctrl(port, port->mctrl);
2589 	}
2590 
2591 	scr_val |= SCSCR_RE | SCSCR_TE |
2592 		   (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2593 	serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2594 	if ((srr + 1 == 5) &&
2595 	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2596 		/*
2597 		 * In asynchronous mode, when the sampling rate is 1/5, first
2598 		 * received data may become invalid on some SCIFA and SCIFB.
2599 		 * To avoid this problem wait more than 1 serial data time (1
2600 		 * bit time x serial data number) after setting SCSCR.RE = 1.
2601 		 */
2602 		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2603 	}
2604 
2605 	/*
2606 	 * Calculate delay for 2 DMA buffers (4 FIFO).
2607 	 * See serial_core.c::uart_update_timeout().
2608 	 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2609 	 * function calculates 1 jiffie for the data plus 5 jiffies for the
2610 	 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2611 	 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2612 	 * value obtained by this formula is too small. Therefore, if the value
2613 	 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2614 	 */
2615 	s->rx_frame = (10000 * bits) / (baud / 100);
2616 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2617 	s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2618 	if (s->rx_timeout < 20)
2619 		s->rx_timeout = 20;
2620 #endif
2621 
2622 	if ((termios->c_cflag & CREAD) != 0)
2623 		sci_start_rx(port);
2624 
2625 	spin_unlock_irqrestore(&port->lock, flags);
2626 
2627 	sci_port_disable(s);
2628 
2629 	if (UART_ENABLE_MS(port, termios->c_cflag))
2630 		sci_enable_ms(port);
2631 }
2632 
2633 static void sci_pm(struct uart_port *port, unsigned int state,
2634 		   unsigned int oldstate)
2635 {
2636 	struct sci_port *sci_port = to_sci_port(port);
2637 
2638 	switch (state) {
2639 	case UART_PM_STATE_OFF:
2640 		sci_port_disable(sci_port);
2641 		break;
2642 	default:
2643 		sci_port_enable(sci_port);
2644 		break;
2645 	}
2646 }
2647 
2648 static const char *sci_type(struct uart_port *port)
2649 {
2650 	switch (port->type) {
2651 	case PORT_IRDA:
2652 		return "irda";
2653 	case PORT_SCI:
2654 		return "sci";
2655 	case PORT_SCIF:
2656 		return "scif";
2657 	case PORT_SCIFA:
2658 		return "scifa";
2659 	case PORT_SCIFB:
2660 		return "scifb";
2661 	case PORT_HSCIF:
2662 		return "hscif";
2663 	}
2664 
2665 	return NULL;
2666 }
2667 
2668 static int sci_remap_port(struct uart_port *port)
2669 {
2670 	struct sci_port *sport = to_sci_port(port);
2671 
2672 	/*
2673 	 * Nothing to do if there's already an established membase.
2674 	 */
2675 	if (port->membase)
2676 		return 0;
2677 
2678 	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2679 		port->membase = ioremap(port->mapbase, sport->reg_size);
2680 		if (unlikely(!port->membase)) {
2681 			dev_err(port->dev, "can't remap port#%d\n", port->line);
2682 			return -ENXIO;
2683 		}
2684 	} else {
2685 		/*
2686 		 * For the simple (and majority of) cases where we don't
2687 		 * need to do any remapping, just cast the cookie
2688 		 * directly.
2689 		 */
2690 		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2691 	}
2692 
2693 	return 0;
2694 }
2695 
2696 static void sci_release_port(struct uart_port *port)
2697 {
2698 	struct sci_port *sport = to_sci_port(port);
2699 
2700 	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2701 		iounmap(port->membase);
2702 		port->membase = NULL;
2703 	}
2704 
2705 	release_mem_region(port->mapbase, sport->reg_size);
2706 }
2707 
2708 static int sci_request_port(struct uart_port *port)
2709 {
2710 	struct resource *res;
2711 	struct sci_port *sport = to_sci_port(port);
2712 	int ret;
2713 
2714 	res = request_mem_region(port->mapbase, sport->reg_size,
2715 				 dev_name(port->dev));
2716 	if (unlikely(res == NULL)) {
2717 		dev_err(port->dev, "request_mem_region failed.");
2718 		return -EBUSY;
2719 	}
2720 
2721 	ret = sci_remap_port(port);
2722 	if (unlikely(ret != 0)) {
2723 		release_resource(res);
2724 		return ret;
2725 	}
2726 
2727 	return 0;
2728 }
2729 
2730 static void sci_config_port(struct uart_port *port, int flags)
2731 {
2732 	if (flags & UART_CONFIG_TYPE) {
2733 		struct sci_port *sport = to_sci_port(port);
2734 
2735 		port->type = sport->cfg->type;
2736 		sci_request_port(port);
2737 	}
2738 }
2739 
2740 static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2741 {
2742 	if (ser->baud_base < 2400)
2743 		/* No paper tape reader for Mitch.. */
2744 		return -EINVAL;
2745 
2746 	return 0;
2747 }
2748 
2749 static const struct uart_ops sci_uart_ops = {
2750 	.tx_empty	= sci_tx_empty,
2751 	.set_mctrl	= sci_set_mctrl,
2752 	.get_mctrl	= sci_get_mctrl,
2753 	.start_tx	= sci_start_tx,
2754 	.stop_tx	= sci_stop_tx,
2755 	.stop_rx	= sci_stop_rx,
2756 	.enable_ms	= sci_enable_ms,
2757 	.break_ctl	= sci_break_ctl,
2758 	.startup	= sci_startup,
2759 	.shutdown	= sci_shutdown,
2760 	.flush_buffer	= sci_flush_buffer,
2761 	.set_termios	= sci_set_termios,
2762 	.pm		= sci_pm,
2763 	.type		= sci_type,
2764 	.release_port	= sci_release_port,
2765 	.request_port	= sci_request_port,
2766 	.config_port	= sci_config_port,
2767 	.verify_port	= sci_verify_port,
2768 #ifdef CONFIG_CONSOLE_POLL
2769 	.poll_get_char	= sci_poll_get_char,
2770 	.poll_put_char	= sci_poll_put_char,
2771 #endif
2772 };
2773 
2774 static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2775 {
2776 	const char *clk_names[] = {
2777 		[SCI_FCK] = "fck",
2778 		[SCI_SCK] = "sck",
2779 		[SCI_BRG_INT] = "brg_int",
2780 		[SCI_SCIF_CLK] = "scif_clk",
2781 	};
2782 	struct clk *clk;
2783 	unsigned int i;
2784 
2785 	if (sci_port->cfg->type == PORT_HSCIF)
2786 		clk_names[SCI_SCK] = "hsck";
2787 
2788 	for (i = 0; i < SCI_NUM_CLKS; i++) {
2789 		clk = devm_clk_get(dev, clk_names[i]);
2790 		if (PTR_ERR(clk) == -EPROBE_DEFER)
2791 			return -EPROBE_DEFER;
2792 
2793 		if (IS_ERR(clk) && i == SCI_FCK) {
2794 			/*
2795 			 * "fck" used to be called "sci_ick", and we need to
2796 			 * maintain DT backward compatibility.
2797 			 */
2798 			clk = devm_clk_get(dev, "sci_ick");
2799 			if (PTR_ERR(clk) == -EPROBE_DEFER)
2800 				return -EPROBE_DEFER;
2801 
2802 			if (!IS_ERR(clk))
2803 				goto found;
2804 
2805 			/*
2806 			 * Not all SH platforms declare a clock lookup entry
2807 			 * for SCI devices, in which case we need to get the
2808 			 * global "peripheral_clk" clock.
2809 			 */
2810 			clk = devm_clk_get(dev, "peripheral_clk");
2811 			if (!IS_ERR(clk))
2812 				goto found;
2813 
2814 			dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2815 				PTR_ERR(clk));
2816 			return PTR_ERR(clk);
2817 		}
2818 
2819 found:
2820 		if (IS_ERR(clk))
2821 			dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2822 				PTR_ERR(clk));
2823 		else
2824 			dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
2825 				clk, clk_get_rate(clk));
2826 		sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2827 	}
2828 	return 0;
2829 }
2830 
2831 static const struct sci_port_params *
2832 sci_probe_regmap(const struct plat_sci_port *cfg)
2833 {
2834 	unsigned int regtype;
2835 
2836 	if (cfg->regtype != SCIx_PROBE_REGTYPE)
2837 		return &sci_port_params[cfg->regtype];
2838 
2839 	switch (cfg->type) {
2840 	case PORT_SCI:
2841 		regtype = SCIx_SCI_REGTYPE;
2842 		break;
2843 	case PORT_IRDA:
2844 		regtype = SCIx_IRDA_REGTYPE;
2845 		break;
2846 	case PORT_SCIFA:
2847 		regtype = SCIx_SCIFA_REGTYPE;
2848 		break;
2849 	case PORT_SCIFB:
2850 		regtype = SCIx_SCIFB_REGTYPE;
2851 		break;
2852 	case PORT_SCIF:
2853 		/*
2854 		 * The SH-4 is a bit of a misnomer here, although that's
2855 		 * where this particular port layout originated. This
2856 		 * configuration (or some slight variation thereof)
2857 		 * remains the dominant model for all SCIFs.
2858 		 */
2859 		regtype = SCIx_SH4_SCIF_REGTYPE;
2860 		break;
2861 	case PORT_HSCIF:
2862 		regtype = SCIx_HSCIF_REGTYPE;
2863 		break;
2864 	default:
2865 		pr_err("Can't probe register map for given port\n");
2866 		return NULL;
2867 	}
2868 
2869 	return &sci_port_params[regtype];
2870 }
2871 
2872 static int sci_init_single(struct platform_device *dev,
2873 			   struct sci_port *sci_port, unsigned int index,
2874 			   const struct plat_sci_port *p, bool early)
2875 {
2876 	struct uart_port *port = &sci_port->port;
2877 	const struct resource *res;
2878 	unsigned int i;
2879 	int ret;
2880 
2881 	sci_port->cfg	= p;
2882 
2883 	port->ops	= &sci_uart_ops;
2884 	port->iotype	= UPIO_MEM;
2885 	port->line	= index;
2886 	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_SH_SCI_CONSOLE);
2887 
2888 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2889 	if (res == NULL)
2890 		return -ENOMEM;
2891 
2892 	port->mapbase = res->start;
2893 	sci_port->reg_size = resource_size(res);
2894 
2895 	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) {
2896 		if (i)
2897 			sci_port->irqs[i] = platform_get_irq_optional(dev, i);
2898 		else
2899 			sci_port->irqs[i] = platform_get_irq(dev, i);
2900 	}
2901 
2902 	/* The SCI generates several interrupts. They can be muxed together or
2903 	 * connected to different interrupt lines. In the muxed case only one
2904 	 * interrupt resource is specified as there is only one interrupt ID.
2905 	 * In the non-muxed case, up to 6 interrupt signals might be generated
2906 	 * from the SCI, however those signals might have their own individual
2907 	 * interrupt ID numbers, or muxed together with another interrupt.
2908 	 */
2909 	if (sci_port->irqs[0] < 0)
2910 		return -ENXIO;
2911 
2912 	if (sci_port->irqs[1] < 0)
2913 		for (i = 1; i < ARRAY_SIZE(sci_port->irqs); i++)
2914 			sci_port->irqs[i] = sci_port->irqs[0];
2915 
2916 	sci_port->params = sci_probe_regmap(p);
2917 	if (unlikely(sci_port->params == NULL))
2918 		return -EINVAL;
2919 
2920 	switch (p->type) {
2921 	case PORT_SCIFB:
2922 		sci_port->rx_trigger = 48;
2923 		break;
2924 	case PORT_HSCIF:
2925 		sci_port->rx_trigger = 64;
2926 		break;
2927 	case PORT_SCIFA:
2928 		sci_port->rx_trigger = 32;
2929 		break;
2930 	case PORT_SCIF:
2931 		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2932 			/* RX triggering not implemented for this IP */
2933 			sci_port->rx_trigger = 1;
2934 		else
2935 			sci_port->rx_trigger = 8;
2936 		break;
2937 	default:
2938 		sci_port->rx_trigger = 1;
2939 		break;
2940 	}
2941 
2942 	sci_port->rx_fifo_timeout = 0;
2943 	sci_port->hscif_tot = 0;
2944 
2945 	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2946 	 * match the SoC datasheet, this should be investigated. Let platform
2947 	 * data override the sampling rate for now.
2948 	 */
2949 	sci_port->sampling_rate_mask = p->sampling_rate
2950 				     ? SCI_SR(p->sampling_rate)
2951 				     : sci_port->params->sampling_rate_mask;
2952 
2953 	if (!early) {
2954 		ret = sci_init_clocks(sci_port, &dev->dev);
2955 		if (ret < 0)
2956 			return ret;
2957 
2958 		port->dev = &dev->dev;
2959 
2960 		pm_runtime_enable(&dev->dev);
2961 	}
2962 
2963 	port->type		= p->type;
2964 	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2965 	port->fifosize		= sci_port->params->fifosize;
2966 
2967 	if (port->type == PORT_SCI) {
2968 		if (sci_port->reg_size >= 0x20)
2969 			port->regshift = 2;
2970 		else
2971 			port->regshift = 1;
2972 	}
2973 
2974 	/*
2975 	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2976 	 * for the multi-IRQ ports, which is where we are primarily
2977 	 * concerned with the shutdown path synchronization.
2978 	 *
2979 	 * For the muxed case there's nothing more to do.
2980 	 */
2981 	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
2982 	port->irqflags		= 0;
2983 
2984 	port->serial_in		= sci_serial_in;
2985 	port->serial_out	= sci_serial_out;
2986 
2987 	return 0;
2988 }
2989 
2990 static void sci_cleanup_single(struct sci_port *port)
2991 {
2992 	pm_runtime_disable(port->port.dev);
2993 }
2994 
2995 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2996     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2997 static void serial_console_putchar(struct uart_port *port, int ch)
2998 {
2999 	sci_poll_put_char(port, ch);
3000 }
3001 
3002 /*
3003  *	Print a string to the serial port trying not to disturb
3004  *	any possible real use of the port...
3005  */
3006 static void serial_console_write(struct console *co, const char *s,
3007 				 unsigned count)
3008 {
3009 	struct sci_port *sci_port = &sci_ports[co->index];
3010 	struct uart_port *port = &sci_port->port;
3011 	unsigned short bits, ctrl, ctrl_temp;
3012 	unsigned long flags;
3013 	int locked = 1;
3014 
3015 	if (port->sysrq)
3016 		locked = 0;
3017 	else if (oops_in_progress)
3018 		locked = spin_trylock_irqsave(&port->lock, flags);
3019 	else
3020 		spin_lock_irqsave(&port->lock, flags);
3021 
3022 	/* first save SCSCR then disable interrupts, keep clock source */
3023 	ctrl = serial_port_in(port, SCSCR);
3024 	ctrl_temp = SCSCR_RE | SCSCR_TE |
3025 		    (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
3026 		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
3027 	serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
3028 
3029 	uart_console_write(port, s, count, serial_console_putchar);
3030 
3031 	/* wait until fifo is empty and last bit has been transmitted */
3032 	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
3033 	while ((serial_port_in(port, SCxSR) & bits) != bits)
3034 		cpu_relax();
3035 
3036 	/* restore the SCSCR */
3037 	serial_port_out(port, SCSCR, ctrl);
3038 
3039 	if (locked)
3040 		spin_unlock_irqrestore(&port->lock, flags);
3041 }
3042 
3043 static int serial_console_setup(struct console *co, char *options)
3044 {
3045 	struct sci_port *sci_port;
3046 	struct uart_port *port;
3047 	int baud = 115200;
3048 	int bits = 8;
3049 	int parity = 'n';
3050 	int flow = 'n';
3051 	int ret;
3052 
3053 	/*
3054 	 * Refuse to handle any bogus ports.
3055 	 */
3056 	if (co->index < 0 || co->index >= SCI_NPORTS)
3057 		return -ENODEV;
3058 
3059 	sci_port = &sci_ports[co->index];
3060 	port = &sci_port->port;
3061 
3062 	/*
3063 	 * Refuse to handle uninitialized ports.
3064 	 */
3065 	if (!port->ops)
3066 		return -ENODEV;
3067 
3068 	ret = sci_remap_port(port);
3069 	if (unlikely(ret != 0))
3070 		return ret;
3071 
3072 	if (options)
3073 		uart_parse_options(options, &baud, &parity, &bits, &flow);
3074 
3075 	return uart_set_options(port, co, baud, parity, bits, flow);
3076 }
3077 
3078 static struct console serial_console = {
3079 	.name		= "ttySC",
3080 	.device		= uart_console_device,
3081 	.write		= serial_console_write,
3082 	.setup		= serial_console_setup,
3083 	.flags		= CON_PRINTBUFFER,
3084 	.index		= -1,
3085 	.data		= &sci_uart_driver,
3086 };
3087 
3088 #ifdef CONFIG_SUPERH
3089 static struct console early_serial_console = {
3090 	.name           = "early_ttySC",
3091 	.write          = serial_console_write,
3092 	.flags          = CON_PRINTBUFFER,
3093 	.index		= -1,
3094 };
3095 
3096 static char early_serial_buf[32];
3097 
3098 static int sci_probe_earlyprintk(struct platform_device *pdev)
3099 {
3100 	const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
3101 
3102 	if (early_serial_console.data)
3103 		return -EEXIST;
3104 
3105 	early_serial_console.index = pdev->id;
3106 
3107 	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
3108 
3109 	serial_console_setup(&early_serial_console, early_serial_buf);
3110 
3111 	if (!strstr(early_serial_buf, "keep"))
3112 		early_serial_console.flags |= CON_BOOT;
3113 
3114 	register_console(&early_serial_console);
3115 	return 0;
3116 }
3117 #endif
3118 
3119 #define SCI_CONSOLE	(&serial_console)
3120 
3121 #else
3122 static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3123 {
3124 	return -EINVAL;
3125 }
3126 
3127 #define SCI_CONSOLE	NULL
3128 
3129 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3130 
3131 static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3132 
3133 static DEFINE_MUTEX(sci_uart_registration_lock);
3134 static struct uart_driver sci_uart_driver = {
3135 	.owner		= THIS_MODULE,
3136 	.driver_name	= "sci",
3137 	.dev_name	= "ttySC",
3138 	.major		= SCI_MAJOR,
3139 	.minor		= SCI_MINOR_START,
3140 	.nr		= SCI_NPORTS,
3141 	.cons		= SCI_CONSOLE,
3142 };
3143 
3144 static int sci_remove(struct platform_device *dev)
3145 {
3146 	struct sci_port *port = platform_get_drvdata(dev);
3147 	unsigned int type = port->port.type;	/* uart_remove_... clears it */
3148 
3149 	sci_ports_in_use &= ~BIT(port->port.line);
3150 	uart_remove_one_port(&sci_uart_driver, &port->port);
3151 
3152 	sci_cleanup_single(port);
3153 
3154 	if (port->port.fifosize > 1)
3155 		device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3156 	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
3157 		device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
3158 
3159 	return 0;
3160 }
3161 
3162 
3163 #define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
3164 #define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
3165 #define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
3166 
3167 static const struct of_device_id of_sci_match[] = {
3168 	/* SoC-specific types */
3169 	{
3170 		.compatible = "renesas,scif-r7s72100",
3171 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3172 	},
3173 	{
3174 		.compatible = "renesas,scif-r7s9210",
3175 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3176 	},
3177 	/* Family-specific types */
3178 	{
3179 		.compatible = "renesas,rcar-gen1-scif",
3180 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3181 	}, {
3182 		.compatible = "renesas,rcar-gen2-scif",
3183 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3184 	}, {
3185 		.compatible = "renesas,rcar-gen3-scif",
3186 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3187 	},
3188 	/* Generic types */
3189 	{
3190 		.compatible = "renesas,scif",
3191 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3192 	}, {
3193 		.compatible = "renesas,scifa",
3194 		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3195 	}, {
3196 		.compatible = "renesas,scifb",
3197 		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3198 	}, {
3199 		.compatible = "renesas,hscif",
3200 		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3201 	}, {
3202 		.compatible = "renesas,sci",
3203 		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3204 	}, {
3205 		/* Terminator */
3206 	},
3207 };
3208 MODULE_DEVICE_TABLE(of, of_sci_match);
3209 
3210 static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3211 					  unsigned int *dev_id)
3212 {
3213 	struct device_node *np = pdev->dev.of_node;
3214 	struct plat_sci_port *p;
3215 	struct sci_port *sp;
3216 	const void *data;
3217 	int id;
3218 
3219 	if (!IS_ENABLED(CONFIG_OF) || !np)
3220 		return NULL;
3221 
3222 	data = of_device_get_match_data(&pdev->dev);
3223 
3224 	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3225 	if (!p)
3226 		return NULL;
3227 
3228 	/* Get the line number from the aliases node. */
3229 	id = of_alias_get_id(np, "serial");
3230 	if (id < 0 && ~sci_ports_in_use)
3231 		id = ffz(sci_ports_in_use);
3232 	if (id < 0) {
3233 		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3234 		return NULL;
3235 	}
3236 	if (id >= ARRAY_SIZE(sci_ports)) {
3237 		dev_err(&pdev->dev, "serial%d out of range\n", id);
3238 		return NULL;
3239 	}
3240 
3241 	sp = &sci_ports[id];
3242 	*dev_id = id;
3243 
3244 	p->type = SCI_OF_TYPE(data);
3245 	p->regtype = SCI_OF_REGTYPE(data);
3246 
3247 	sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3248 
3249 	return p;
3250 }
3251 
3252 static int sci_probe_single(struct platform_device *dev,
3253 				      unsigned int index,
3254 				      struct plat_sci_port *p,
3255 				      struct sci_port *sciport)
3256 {
3257 	int ret;
3258 
3259 	/* Sanity check */
3260 	if (unlikely(index >= SCI_NPORTS)) {
3261 		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3262 			   index+1, SCI_NPORTS);
3263 		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3264 		return -EINVAL;
3265 	}
3266 	BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
3267 	if (sci_ports_in_use & BIT(index))
3268 		return -EBUSY;
3269 
3270 	mutex_lock(&sci_uart_registration_lock);
3271 	if (!sci_uart_driver.state) {
3272 		ret = uart_register_driver(&sci_uart_driver);
3273 		if (ret) {
3274 			mutex_unlock(&sci_uart_registration_lock);
3275 			return ret;
3276 		}
3277 	}
3278 	mutex_unlock(&sci_uart_registration_lock);
3279 
3280 	ret = sci_init_single(dev, sciport, index, p, false);
3281 	if (ret)
3282 		return ret;
3283 
3284 	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3285 	if (IS_ERR(sciport->gpios))
3286 		return PTR_ERR(sciport->gpios);
3287 
3288 	if (sciport->has_rtscts) {
3289 		if (mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_CTS) ||
3290 		    mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_RTS)) {
3291 			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3292 			return -EINVAL;
3293 		}
3294 		sciport->port.flags |= UPF_HARD_FLOW;
3295 	}
3296 
3297 	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3298 	if (ret) {
3299 		sci_cleanup_single(sciport);
3300 		return ret;
3301 	}
3302 
3303 	return 0;
3304 }
3305 
3306 static int sci_probe(struct platform_device *dev)
3307 {
3308 	struct plat_sci_port *p;
3309 	struct sci_port *sp;
3310 	unsigned int dev_id;
3311 	int ret;
3312 
3313 	/*
3314 	 * If we've come here via earlyprintk initialization, head off to
3315 	 * the special early probe. We don't have sufficient device state
3316 	 * to make it beyond this yet.
3317 	 */
3318 #ifdef CONFIG_SUPERH
3319 	if (is_sh_early_platform_device(dev))
3320 		return sci_probe_earlyprintk(dev);
3321 #endif
3322 
3323 	if (dev->dev.of_node) {
3324 		p = sci_parse_dt(dev, &dev_id);
3325 		if (p == NULL)
3326 			return -EINVAL;
3327 	} else {
3328 		p = dev->dev.platform_data;
3329 		if (p == NULL) {
3330 			dev_err(&dev->dev, "no platform data supplied\n");
3331 			return -EINVAL;
3332 		}
3333 
3334 		dev_id = dev->id;
3335 	}
3336 
3337 	sp = &sci_ports[dev_id];
3338 	platform_set_drvdata(dev, sp);
3339 
3340 	ret = sci_probe_single(dev, dev_id, p, sp);
3341 	if (ret)
3342 		return ret;
3343 
3344 	if (sp->port.fifosize > 1) {
3345 		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3346 		if (ret)
3347 			return ret;
3348 	}
3349 	if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3350 	    sp->port.type == PORT_HSCIF) {
3351 		ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
3352 		if (ret) {
3353 			if (sp->port.fifosize > 1) {
3354 				device_remove_file(&dev->dev,
3355 						   &dev_attr_rx_fifo_trigger);
3356 			}
3357 			return ret;
3358 		}
3359 	}
3360 
3361 #ifdef CONFIG_SH_STANDARD_BIOS
3362 	sh_bios_gdb_detach();
3363 #endif
3364 
3365 	sci_ports_in_use |= BIT(dev_id);
3366 	return 0;
3367 }
3368 
3369 static __maybe_unused int sci_suspend(struct device *dev)
3370 {
3371 	struct sci_port *sport = dev_get_drvdata(dev);
3372 
3373 	if (sport)
3374 		uart_suspend_port(&sci_uart_driver, &sport->port);
3375 
3376 	return 0;
3377 }
3378 
3379 static __maybe_unused int sci_resume(struct device *dev)
3380 {
3381 	struct sci_port *sport = dev_get_drvdata(dev);
3382 
3383 	if (sport)
3384 		uart_resume_port(&sci_uart_driver, &sport->port);
3385 
3386 	return 0;
3387 }
3388 
3389 static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3390 
3391 static struct platform_driver sci_driver = {
3392 	.probe		= sci_probe,
3393 	.remove		= sci_remove,
3394 	.driver		= {
3395 		.name	= "sh-sci",
3396 		.pm	= &sci_dev_pm_ops,
3397 		.of_match_table = of_match_ptr(of_sci_match),
3398 	},
3399 };
3400 
3401 static int __init sci_init(void)
3402 {
3403 	pr_info("%s\n", banner);
3404 
3405 	return platform_driver_register(&sci_driver);
3406 }
3407 
3408 static void __exit sci_exit(void)
3409 {
3410 	platform_driver_unregister(&sci_driver);
3411 
3412 	if (sci_uart_driver.state)
3413 		uart_unregister_driver(&sci_uart_driver);
3414 }
3415 
3416 #if defined(CONFIG_SUPERH) && defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
3417 sh_early_platform_init_buffer("earlyprintk", &sci_driver,
3418 			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3419 #endif
3420 #ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3421 static struct plat_sci_port port_cfg __initdata;
3422 
3423 static int __init early_console_setup(struct earlycon_device *device,
3424 				      int type)
3425 {
3426 	if (!device->port.membase)
3427 		return -ENODEV;
3428 
3429 	device->port.serial_in = sci_serial_in;
3430 	device->port.serial_out	= sci_serial_out;
3431 	device->port.type = type;
3432 	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3433 	port_cfg.type = type;
3434 	sci_ports[0].cfg = &port_cfg;
3435 	sci_ports[0].params = sci_probe_regmap(&port_cfg);
3436 	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3437 	sci_serial_out(&sci_ports[0].port, SCSCR,
3438 		       SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3439 
3440 	device->con->write = serial_console_write;
3441 	return 0;
3442 }
3443 static int __init sci_early_console_setup(struct earlycon_device *device,
3444 					  const char *opt)
3445 {
3446 	return early_console_setup(device, PORT_SCI);
3447 }
3448 static int __init scif_early_console_setup(struct earlycon_device *device,
3449 					  const char *opt)
3450 {
3451 	return early_console_setup(device, PORT_SCIF);
3452 }
3453 static int __init rzscifa_early_console_setup(struct earlycon_device *device,
3454 					  const char *opt)
3455 {
3456 	port_cfg.regtype = SCIx_RZ_SCIFA_REGTYPE;
3457 	return early_console_setup(device, PORT_SCIF);
3458 }
3459 static int __init scifa_early_console_setup(struct earlycon_device *device,
3460 					  const char *opt)
3461 {
3462 	return early_console_setup(device, PORT_SCIFA);
3463 }
3464 static int __init scifb_early_console_setup(struct earlycon_device *device,
3465 					  const char *opt)
3466 {
3467 	return early_console_setup(device, PORT_SCIFB);
3468 }
3469 static int __init hscif_early_console_setup(struct earlycon_device *device,
3470 					  const char *opt)
3471 {
3472 	return early_console_setup(device, PORT_HSCIF);
3473 }
3474 
3475 OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3476 OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3477 OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rzscifa_early_console_setup);
3478 OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3479 OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3480 OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3481 #endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3482 
3483 module_init(sci_init);
3484 module_exit(sci_exit);
3485 
3486 MODULE_LICENSE("GPL");
3487 MODULE_ALIAS("platform:sh-sci");
3488 MODULE_AUTHOR("Paul Mundt");
3489 MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
3490