xref: /openbmc/linux/drivers/tty/serial/sh-sci.c (revision ccb01374)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * SuperH on-chip serial module support.  (SCI with no FIFO / with FIFO)
4  *
5  *  Copyright (C) 2002 - 2011  Paul Mundt
6  *  Copyright (C) 2015 Glider bvba
7  *  Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
8  *
9  * based off of the old drivers/char/sh-sci.c by:
10  *
11  *   Copyright (C) 1999, 2000  Niibe Yutaka
12  *   Copyright (C) 2000  Sugioka Toshinobu
13  *   Modified to support multiple serial ports. Stuart Menefy (May 2000).
14  *   Modified to support SecureEdge. David McCullough (2002)
15  *   Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
16  *   Removed SH7300 support (Jul 2007).
17  */
18 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
19 #define SUPPORT_SYSRQ
20 #endif
21 
22 #undef DEBUG
23 
24 #include <linux/clk.h>
25 #include <linux/console.h>
26 #include <linux/ctype.h>
27 #include <linux/cpufreq.h>
28 #include <linux/delay.h>
29 #include <linux/dmaengine.h>
30 #include <linux/dma-mapping.h>
31 #include <linux/err.h>
32 #include <linux/errno.h>
33 #include <linux/init.h>
34 #include <linux/interrupt.h>
35 #include <linux/ioport.h>
36 #include <linux/ktime.h>
37 #include <linux/major.h>
38 #include <linux/module.h>
39 #include <linux/mm.h>
40 #include <linux/of.h>
41 #include <linux/of_device.h>
42 #include <linux/platform_device.h>
43 #include <linux/pm_runtime.h>
44 #include <linux/scatterlist.h>
45 #include <linux/serial.h>
46 #include <linux/serial_sci.h>
47 #include <linux/sh_dma.h>
48 #include <linux/slab.h>
49 #include <linux/string.h>
50 #include <linux/sysrq.h>
51 #include <linux/timer.h>
52 #include <linux/tty.h>
53 #include <linux/tty_flip.h>
54 
55 #ifdef CONFIG_SUPERH
56 #include <asm/sh_bios.h>
57 #endif
58 
59 #include "serial_mctrl_gpio.h"
60 #include "sh-sci.h"
61 
62 /* Offsets into the sci_port->irqs array */
63 enum {
64 	SCIx_ERI_IRQ,
65 	SCIx_RXI_IRQ,
66 	SCIx_TXI_IRQ,
67 	SCIx_BRI_IRQ,
68 	SCIx_DRI_IRQ,
69 	SCIx_TEI_IRQ,
70 	SCIx_NR_IRQS,
71 
72 	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
73 };
74 
75 #define SCIx_IRQ_IS_MUXED(port)			\
76 	((port)->irqs[SCIx_ERI_IRQ] ==	\
77 	 (port)->irqs[SCIx_RXI_IRQ]) ||	\
78 	((port)->irqs[SCIx_ERI_IRQ] &&	\
79 	 ((port)->irqs[SCIx_RXI_IRQ] < 0))
80 
81 enum SCI_CLKS {
82 	SCI_FCK,		/* Functional Clock */
83 	SCI_SCK,		/* Optional External Clock */
84 	SCI_BRG_INT,		/* Optional BRG Internal Clock Source */
85 	SCI_SCIF_CLK,		/* Optional BRG External Clock Source */
86 	SCI_NUM_CLKS
87 };
88 
89 /* Bit x set means sampling rate x + 1 is supported */
90 #define SCI_SR(x)		BIT((x) - 1)
91 #define SCI_SR_RANGE(x, y)	GENMASK((y) - 1, (x) - 1)
92 
93 #define SCI_SR_SCIFAB		SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
94 				SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
95 				SCI_SR(19) | SCI_SR(27)
96 
97 #define min_sr(_port)		ffs((_port)->sampling_rate_mask)
98 #define max_sr(_port)		fls((_port)->sampling_rate_mask)
99 
100 /* Iterate over all supported sampling rates, from high to low */
101 #define for_each_sr(_sr, _port)						\
102 	for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--)	\
103 		if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
104 
105 struct plat_sci_reg {
106 	u8 offset, size;
107 };
108 
109 struct sci_port_params {
110 	const struct plat_sci_reg regs[SCIx_NR_REGS];
111 	unsigned int fifosize;
112 	unsigned int overrun_reg;
113 	unsigned int overrun_mask;
114 	unsigned int sampling_rate_mask;
115 	unsigned int error_mask;
116 	unsigned int error_clear;
117 };
118 
119 struct sci_port {
120 	struct uart_port	port;
121 
122 	/* Platform configuration */
123 	const struct sci_port_params *params;
124 	const struct plat_sci_port *cfg;
125 	unsigned int		sampling_rate_mask;
126 	resource_size_t		reg_size;
127 	struct mctrl_gpios	*gpios;
128 
129 	/* Clocks */
130 	struct clk		*clks[SCI_NUM_CLKS];
131 	unsigned long		clk_rates[SCI_NUM_CLKS];
132 
133 	int			irqs[SCIx_NR_IRQS];
134 	char			*irqstr[SCIx_NR_IRQS];
135 
136 	struct dma_chan			*chan_tx;
137 	struct dma_chan			*chan_rx;
138 
139 #ifdef CONFIG_SERIAL_SH_SCI_DMA
140 	struct dma_chan			*chan_tx_saved;
141 	struct dma_chan			*chan_rx_saved;
142 	dma_cookie_t			cookie_tx;
143 	dma_cookie_t			cookie_rx[2];
144 	dma_cookie_t			active_rx;
145 	dma_addr_t			tx_dma_addr;
146 	unsigned int			tx_dma_len;
147 	struct scatterlist		sg_rx[2];
148 	void				*rx_buf[2];
149 	size_t				buf_len_rx;
150 	struct work_struct		work_tx;
151 	struct hrtimer			rx_timer;
152 	unsigned int			rx_timeout;	/* microseconds */
153 #endif
154 	unsigned int			rx_frame;
155 	int				rx_trigger;
156 	struct timer_list		rx_fifo_timer;
157 	int				rx_fifo_timeout;
158 	u16				hscif_tot;
159 
160 	bool has_rtscts;
161 	bool autorts;
162 };
163 
164 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
165 
166 static struct sci_port sci_ports[SCI_NPORTS];
167 static unsigned long sci_ports_in_use;
168 static struct uart_driver sci_uart_driver;
169 
170 static inline struct sci_port *
171 to_sci_port(struct uart_port *uart)
172 {
173 	return container_of(uart, struct sci_port, port);
174 }
175 
176 static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
177 	/*
178 	 * Common SCI definitions, dependent on the port's regshift
179 	 * value.
180 	 */
181 	[SCIx_SCI_REGTYPE] = {
182 		.regs = {
183 			[SCSMR]		= { 0x00,  8 },
184 			[SCBRR]		= { 0x01,  8 },
185 			[SCSCR]		= { 0x02,  8 },
186 			[SCxTDR]	= { 0x03,  8 },
187 			[SCxSR]		= { 0x04,  8 },
188 			[SCxRDR]	= { 0x05,  8 },
189 		},
190 		.fifosize = 1,
191 		.overrun_reg = SCxSR,
192 		.overrun_mask = SCI_ORER,
193 		.sampling_rate_mask = SCI_SR(32),
194 		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
195 		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
196 	},
197 
198 	/*
199 	 * Common definitions for legacy IrDA ports.
200 	 */
201 	[SCIx_IRDA_REGTYPE] = {
202 		.regs = {
203 			[SCSMR]		= { 0x00,  8 },
204 			[SCBRR]		= { 0x02,  8 },
205 			[SCSCR]		= { 0x04,  8 },
206 			[SCxTDR]	= { 0x06,  8 },
207 			[SCxSR]		= { 0x08, 16 },
208 			[SCxRDR]	= { 0x0a,  8 },
209 			[SCFCR]		= { 0x0c,  8 },
210 			[SCFDR]		= { 0x0e, 16 },
211 		},
212 		.fifosize = 1,
213 		.overrun_reg = SCxSR,
214 		.overrun_mask = SCI_ORER,
215 		.sampling_rate_mask = SCI_SR(32),
216 		.error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
217 		.error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
218 	},
219 
220 	/*
221 	 * Common SCIFA definitions.
222 	 */
223 	[SCIx_SCIFA_REGTYPE] = {
224 		.regs = {
225 			[SCSMR]		= { 0x00, 16 },
226 			[SCBRR]		= { 0x04,  8 },
227 			[SCSCR]		= { 0x08, 16 },
228 			[SCxTDR]	= { 0x20,  8 },
229 			[SCxSR]		= { 0x14, 16 },
230 			[SCxRDR]	= { 0x24,  8 },
231 			[SCFCR]		= { 0x18, 16 },
232 			[SCFDR]		= { 0x1c, 16 },
233 			[SCPCR]		= { 0x30, 16 },
234 			[SCPDR]		= { 0x34, 16 },
235 		},
236 		.fifosize = 64,
237 		.overrun_reg = SCxSR,
238 		.overrun_mask = SCIFA_ORER,
239 		.sampling_rate_mask = SCI_SR_SCIFAB,
240 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
241 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
242 	},
243 
244 	/*
245 	 * Common SCIFB definitions.
246 	 */
247 	[SCIx_SCIFB_REGTYPE] = {
248 		.regs = {
249 			[SCSMR]		= { 0x00, 16 },
250 			[SCBRR]		= { 0x04,  8 },
251 			[SCSCR]		= { 0x08, 16 },
252 			[SCxTDR]	= { 0x40,  8 },
253 			[SCxSR]		= { 0x14, 16 },
254 			[SCxRDR]	= { 0x60,  8 },
255 			[SCFCR]		= { 0x18, 16 },
256 			[SCTFDR]	= { 0x38, 16 },
257 			[SCRFDR]	= { 0x3c, 16 },
258 			[SCPCR]		= { 0x30, 16 },
259 			[SCPDR]		= { 0x34, 16 },
260 		},
261 		.fifosize = 256,
262 		.overrun_reg = SCxSR,
263 		.overrun_mask = SCIFA_ORER,
264 		.sampling_rate_mask = SCI_SR_SCIFAB,
265 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
266 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
267 	},
268 
269 	/*
270 	 * Common SH-2(A) SCIF definitions for ports with FIFO data
271 	 * count registers.
272 	 */
273 	[SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
274 		.regs = {
275 			[SCSMR]		= { 0x00, 16 },
276 			[SCBRR]		= { 0x04,  8 },
277 			[SCSCR]		= { 0x08, 16 },
278 			[SCxTDR]	= { 0x0c,  8 },
279 			[SCxSR]		= { 0x10, 16 },
280 			[SCxRDR]	= { 0x14,  8 },
281 			[SCFCR]		= { 0x18, 16 },
282 			[SCFDR]		= { 0x1c, 16 },
283 			[SCSPTR]	= { 0x20, 16 },
284 			[SCLSR]		= { 0x24, 16 },
285 		},
286 		.fifosize = 16,
287 		.overrun_reg = SCLSR,
288 		.overrun_mask = SCLSR_ORER,
289 		.sampling_rate_mask = SCI_SR(32),
290 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
291 		.error_clear = SCIF_ERROR_CLEAR,
292 	},
293 
294 	/*
295 	 * The "SCIFA" that is in RZ/T and RZ/A2.
296 	 * It looks like a normal SCIF with FIFO data, but with a
297 	 * compressed address space. Also, the break out of interrupts
298 	 * are different: ERI/BRI, RXI, TXI, TEI, DRI.
299 	 */
300 	[SCIx_RZ_SCIFA_REGTYPE] = {
301 		.regs = {
302 			[SCSMR]		= { 0x00, 16 },
303 			[SCBRR]		= { 0x02,  8 },
304 			[SCSCR]		= { 0x04, 16 },
305 			[SCxTDR]	= { 0x06,  8 },
306 			[SCxSR]		= { 0x08, 16 },
307 			[SCxRDR]	= { 0x0A,  8 },
308 			[SCFCR]		= { 0x0C, 16 },
309 			[SCFDR]		= { 0x0E, 16 },
310 			[SCSPTR]	= { 0x10, 16 },
311 			[SCLSR]		= { 0x12, 16 },
312 		},
313 		.fifosize = 16,
314 		.overrun_reg = SCLSR,
315 		.overrun_mask = SCLSR_ORER,
316 		.sampling_rate_mask = SCI_SR(32),
317 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
318 		.error_clear = SCIF_ERROR_CLEAR,
319 	},
320 
321 	/*
322 	 * Common SH-3 SCIF definitions.
323 	 */
324 	[SCIx_SH3_SCIF_REGTYPE] = {
325 		.regs = {
326 			[SCSMR]		= { 0x00,  8 },
327 			[SCBRR]		= { 0x02,  8 },
328 			[SCSCR]		= { 0x04,  8 },
329 			[SCxTDR]	= { 0x06,  8 },
330 			[SCxSR]		= { 0x08, 16 },
331 			[SCxRDR]	= { 0x0a,  8 },
332 			[SCFCR]		= { 0x0c,  8 },
333 			[SCFDR]		= { 0x0e, 16 },
334 		},
335 		.fifosize = 16,
336 		.overrun_reg = SCLSR,
337 		.overrun_mask = SCLSR_ORER,
338 		.sampling_rate_mask = SCI_SR(32),
339 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
340 		.error_clear = SCIF_ERROR_CLEAR,
341 	},
342 
343 	/*
344 	 * Common SH-4(A) SCIF(B) definitions.
345 	 */
346 	[SCIx_SH4_SCIF_REGTYPE] = {
347 		.regs = {
348 			[SCSMR]		= { 0x00, 16 },
349 			[SCBRR]		= { 0x04,  8 },
350 			[SCSCR]		= { 0x08, 16 },
351 			[SCxTDR]	= { 0x0c,  8 },
352 			[SCxSR]		= { 0x10, 16 },
353 			[SCxRDR]	= { 0x14,  8 },
354 			[SCFCR]		= { 0x18, 16 },
355 			[SCFDR]		= { 0x1c, 16 },
356 			[SCSPTR]	= { 0x20, 16 },
357 			[SCLSR]		= { 0x24, 16 },
358 		},
359 		.fifosize = 16,
360 		.overrun_reg = SCLSR,
361 		.overrun_mask = SCLSR_ORER,
362 		.sampling_rate_mask = SCI_SR(32),
363 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
364 		.error_clear = SCIF_ERROR_CLEAR,
365 	},
366 
367 	/*
368 	 * Common SCIF definitions for ports with a Baud Rate Generator for
369 	 * External Clock (BRG).
370 	 */
371 	[SCIx_SH4_SCIF_BRG_REGTYPE] = {
372 		.regs = {
373 			[SCSMR]		= { 0x00, 16 },
374 			[SCBRR]		= { 0x04,  8 },
375 			[SCSCR]		= { 0x08, 16 },
376 			[SCxTDR]	= { 0x0c,  8 },
377 			[SCxSR]		= { 0x10, 16 },
378 			[SCxRDR]	= { 0x14,  8 },
379 			[SCFCR]		= { 0x18, 16 },
380 			[SCFDR]		= { 0x1c, 16 },
381 			[SCSPTR]	= { 0x20, 16 },
382 			[SCLSR]		= { 0x24, 16 },
383 			[SCDL]		= { 0x30, 16 },
384 			[SCCKS]		= { 0x34, 16 },
385 		},
386 		.fifosize = 16,
387 		.overrun_reg = SCLSR,
388 		.overrun_mask = SCLSR_ORER,
389 		.sampling_rate_mask = SCI_SR(32),
390 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
391 		.error_clear = SCIF_ERROR_CLEAR,
392 	},
393 
394 	/*
395 	 * Common HSCIF definitions.
396 	 */
397 	[SCIx_HSCIF_REGTYPE] = {
398 		.regs = {
399 			[SCSMR]		= { 0x00, 16 },
400 			[SCBRR]		= { 0x04,  8 },
401 			[SCSCR]		= { 0x08, 16 },
402 			[SCxTDR]	= { 0x0c,  8 },
403 			[SCxSR]		= { 0x10, 16 },
404 			[SCxRDR]	= { 0x14,  8 },
405 			[SCFCR]		= { 0x18, 16 },
406 			[SCFDR]		= { 0x1c, 16 },
407 			[SCSPTR]	= { 0x20, 16 },
408 			[SCLSR]		= { 0x24, 16 },
409 			[HSSRR]		= { 0x40, 16 },
410 			[SCDL]		= { 0x30, 16 },
411 			[SCCKS]		= { 0x34, 16 },
412 			[HSRTRGR]	= { 0x54, 16 },
413 			[HSTTRGR]	= { 0x58, 16 },
414 		},
415 		.fifosize = 128,
416 		.overrun_reg = SCLSR,
417 		.overrun_mask = SCLSR_ORER,
418 		.sampling_rate_mask = SCI_SR_RANGE(8, 32),
419 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
420 		.error_clear = SCIF_ERROR_CLEAR,
421 	},
422 
423 	/*
424 	 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
425 	 * register.
426 	 */
427 	[SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
428 		.regs = {
429 			[SCSMR]		= { 0x00, 16 },
430 			[SCBRR]		= { 0x04,  8 },
431 			[SCSCR]		= { 0x08, 16 },
432 			[SCxTDR]	= { 0x0c,  8 },
433 			[SCxSR]		= { 0x10, 16 },
434 			[SCxRDR]	= { 0x14,  8 },
435 			[SCFCR]		= { 0x18, 16 },
436 			[SCFDR]		= { 0x1c, 16 },
437 			[SCLSR]		= { 0x24, 16 },
438 		},
439 		.fifosize = 16,
440 		.overrun_reg = SCLSR,
441 		.overrun_mask = SCLSR_ORER,
442 		.sampling_rate_mask = SCI_SR(32),
443 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
444 		.error_clear = SCIF_ERROR_CLEAR,
445 	},
446 
447 	/*
448 	 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
449 	 * count registers.
450 	 */
451 	[SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
452 		.regs = {
453 			[SCSMR]		= { 0x00, 16 },
454 			[SCBRR]		= { 0x04,  8 },
455 			[SCSCR]		= { 0x08, 16 },
456 			[SCxTDR]	= { 0x0c,  8 },
457 			[SCxSR]		= { 0x10, 16 },
458 			[SCxRDR]	= { 0x14,  8 },
459 			[SCFCR]		= { 0x18, 16 },
460 			[SCFDR]		= { 0x1c, 16 },
461 			[SCTFDR]	= { 0x1c, 16 },	/* aliased to SCFDR */
462 			[SCRFDR]	= { 0x20, 16 },
463 			[SCSPTR]	= { 0x24, 16 },
464 			[SCLSR]		= { 0x28, 16 },
465 		},
466 		.fifosize = 16,
467 		.overrun_reg = SCLSR,
468 		.overrun_mask = SCLSR_ORER,
469 		.sampling_rate_mask = SCI_SR(32),
470 		.error_mask = SCIF_DEFAULT_ERROR_MASK,
471 		.error_clear = SCIF_ERROR_CLEAR,
472 	},
473 
474 	/*
475 	 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
476 	 * registers.
477 	 */
478 	[SCIx_SH7705_SCIF_REGTYPE] = {
479 		.regs = {
480 			[SCSMR]		= { 0x00, 16 },
481 			[SCBRR]		= { 0x04,  8 },
482 			[SCSCR]		= { 0x08, 16 },
483 			[SCxTDR]	= { 0x20,  8 },
484 			[SCxSR]		= { 0x14, 16 },
485 			[SCxRDR]	= { 0x24,  8 },
486 			[SCFCR]		= { 0x18, 16 },
487 			[SCFDR]		= { 0x1c, 16 },
488 		},
489 		.fifosize = 64,
490 		.overrun_reg = SCxSR,
491 		.overrun_mask = SCIFA_ORER,
492 		.sampling_rate_mask = SCI_SR(16),
493 		.error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
494 		.error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
495 	},
496 };
497 
498 #define sci_getreg(up, offset)		(&to_sci_port(up)->params->regs[offset])
499 
500 /*
501  * The "offset" here is rather misleading, in that it refers to an enum
502  * value relative to the port mapping rather than the fixed offset
503  * itself, which needs to be manually retrieved from the platform's
504  * register map for the given port.
505  */
506 static unsigned int sci_serial_in(struct uart_port *p, int offset)
507 {
508 	const struct plat_sci_reg *reg = sci_getreg(p, offset);
509 
510 	if (reg->size == 8)
511 		return ioread8(p->membase + (reg->offset << p->regshift));
512 	else if (reg->size == 16)
513 		return ioread16(p->membase + (reg->offset << p->regshift));
514 	else
515 		WARN(1, "Invalid register access\n");
516 
517 	return 0;
518 }
519 
520 static void sci_serial_out(struct uart_port *p, int offset, int value)
521 {
522 	const struct plat_sci_reg *reg = sci_getreg(p, offset);
523 
524 	if (reg->size == 8)
525 		iowrite8(value, p->membase + (reg->offset << p->regshift));
526 	else if (reg->size == 16)
527 		iowrite16(value, p->membase + (reg->offset << p->regshift));
528 	else
529 		WARN(1, "Invalid register access\n");
530 }
531 
532 static void sci_port_enable(struct sci_port *sci_port)
533 {
534 	unsigned int i;
535 
536 	if (!sci_port->port.dev)
537 		return;
538 
539 	pm_runtime_get_sync(sci_port->port.dev);
540 
541 	for (i = 0; i < SCI_NUM_CLKS; i++) {
542 		clk_prepare_enable(sci_port->clks[i]);
543 		sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
544 	}
545 	sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
546 }
547 
548 static void sci_port_disable(struct sci_port *sci_port)
549 {
550 	unsigned int i;
551 
552 	if (!sci_port->port.dev)
553 		return;
554 
555 	for (i = SCI_NUM_CLKS; i-- > 0; )
556 		clk_disable_unprepare(sci_port->clks[i]);
557 
558 	pm_runtime_put_sync(sci_port->port.dev);
559 }
560 
561 static inline unsigned long port_rx_irq_mask(struct uart_port *port)
562 {
563 	/*
564 	 * Not all ports (such as SCIFA) will support REIE. Rather than
565 	 * special-casing the port type, we check the port initialization
566 	 * IRQ enable mask to see whether the IRQ is desired at all. If
567 	 * it's unset, it's logically inferred that there's no point in
568 	 * testing for it.
569 	 */
570 	return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
571 }
572 
573 static void sci_start_tx(struct uart_port *port)
574 {
575 	struct sci_port *s = to_sci_port(port);
576 	unsigned short ctrl;
577 
578 #ifdef CONFIG_SERIAL_SH_SCI_DMA
579 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
580 		u16 new, scr = serial_port_in(port, SCSCR);
581 		if (s->chan_tx)
582 			new = scr | SCSCR_TDRQE;
583 		else
584 			new = scr & ~SCSCR_TDRQE;
585 		if (new != scr)
586 			serial_port_out(port, SCSCR, new);
587 	}
588 
589 	if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
590 	    dma_submit_error(s->cookie_tx)) {
591 		s->cookie_tx = 0;
592 		schedule_work(&s->work_tx);
593 	}
594 #endif
595 
596 	if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
597 		/* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
598 		ctrl = serial_port_in(port, SCSCR);
599 		serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
600 	}
601 }
602 
603 static void sci_stop_tx(struct uart_port *port)
604 {
605 	unsigned short ctrl;
606 
607 	/* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
608 	ctrl = serial_port_in(port, SCSCR);
609 
610 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
611 		ctrl &= ~SCSCR_TDRQE;
612 
613 	ctrl &= ~SCSCR_TIE;
614 
615 	serial_port_out(port, SCSCR, ctrl);
616 }
617 
618 static void sci_start_rx(struct uart_port *port)
619 {
620 	unsigned short ctrl;
621 
622 	ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
623 
624 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
625 		ctrl &= ~SCSCR_RDRQE;
626 
627 	serial_port_out(port, SCSCR, ctrl);
628 }
629 
630 static void sci_stop_rx(struct uart_port *port)
631 {
632 	unsigned short ctrl;
633 
634 	ctrl = serial_port_in(port, SCSCR);
635 
636 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
637 		ctrl &= ~SCSCR_RDRQE;
638 
639 	ctrl &= ~port_rx_irq_mask(port);
640 
641 	serial_port_out(port, SCSCR, ctrl);
642 }
643 
644 static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
645 {
646 	if (port->type == PORT_SCI) {
647 		/* Just store the mask */
648 		serial_port_out(port, SCxSR, mask);
649 	} else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
650 		/* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
651 		/* Only clear the status bits we want to clear */
652 		serial_port_out(port, SCxSR,
653 				serial_port_in(port, SCxSR) & mask);
654 	} else {
655 		/* Store the mask, clear parity/framing errors */
656 		serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
657 	}
658 }
659 
660 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
661     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
662 
663 #ifdef CONFIG_CONSOLE_POLL
664 static int sci_poll_get_char(struct uart_port *port)
665 {
666 	unsigned short status;
667 	int c;
668 
669 	do {
670 		status = serial_port_in(port, SCxSR);
671 		if (status & SCxSR_ERRORS(port)) {
672 			sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
673 			continue;
674 		}
675 		break;
676 	} while (1);
677 
678 	if (!(status & SCxSR_RDxF(port)))
679 		return NO_POLL_CHAR;
680 
681 	c = serial_port_in(port, SCxRDR);
682 
683 	/* Dummy read */
684 	serial_port_in(port, SCxSR);
685 	sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
686 
687 	return c;
688 }
689 #endif
690 
691 static void sci_poll_put_char(struct uart_port *port, unsigned char c)
692 {
693 	unsigned short status;
694 
695 	do {
696 		status = serial_port_in(port, SCxSR);
697 	} while (!(status & SCxSR_TDxE(port)));
698 
699 	serial_port_out(port, SCxTDR, c);
700 	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
701 }
702 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
703 	  CONFIG_SERIAL_SH_SCI_EARLYCON */
704 
705 static void sci_init_pins(struct uart_port *port, unsigned int cflag)
706 {
707 	struct sci_port *s = to_sci_port(port);
708 
709 	/*
710 	 * Use port-specific handler if provided.
711 	 */
712 	if (s->cfg->ops && s->cfg->ops->init_pins) {
713 		s->cfg->ops->init_pins(port, cflag);
714 		return;
715 	}
716 
717 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
718 		u16 data = serial_port_in(port, SCPDR);
719 		u16 ctrl = serial_port_in(port, SCPCR);
720 
721 		/* Enable RXD and TXD pin functions */
722 		ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
723 		if (to_sci_port(port)->has_rtscts) {
724 			/* RTS# is output, active low, unless autorts */
725 			if (!(port->mctrl & TIOCM_RTS)) {
726 				ctrl |= SCPCR_RTSC;
727 				data |= SCPDR_RTSD;
728 			} else if (!s->autorts) {
729 				ctrl |= SCPCR_RTSC;
730 				data &= ~SCPDR_RTSD;
731 			} else {
732 				/* Enable RTS# pin function */
733 				ctrl &= ~SCPCR_RTSC;
734 			}
735 			/* Enable CTS# pin function */
736 			ctrl &= ~SCPCR_CTSC;
737 		}
738 		serial_port_out(port, SCPDR, data);
739 		serial_port_out(port, SCPCR, ctrl);
740 	} else if (sci_getreg(port, SCSPTR)->size) {
741 		u16 status = serial_port_in(port, SCSPTR);
742 
743 		/* RTS# is always output; and active low, unless autorts */
744 		status |= SCSPTR_RTSIO;
745 		if (!(port->mctrl & TIOCM_RTS))
746 			status |= SCSPTR_RTSDT;
747 		else if (!s->autorts)
748 			status &= ~SCSPTR_RTSDT;
749 		/* CTS# and SCK are inputs */
750 		status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
751 		serial_port_out(port, SCSPTR, status);
752 	}
753 }
754 
755 static int sci_txfill(struct uart_port *port)
756 {
757 	struct sci_port *s = to_sci_port(port);
758 	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
759 	const struct plat_sci_reg *reg;
760 
761 	reg = sci_getreg(port, SCTFDR);
762 	if (reg->size)
763 		return serial_port_in(port, SCTFDR) & fifo_mask;
764 
765 	reg = sci_getreg(port, SCFDR);
766 	if (reg->size)
767 		return serial_port_in(port, SCFDR) >> 8;
768 
769 	return !(serial_port_in(port, SCxSR) & SCI_TDRE);
770 }
771 
772 static int sci_txroom(struct uart_port *port)
773 {
774 	return port->fifosize - sci_txfill(port);
775 }
776 
777 static int sci_rxfill(struct uart_port *port)
778 {
779 	struct sci_port *s = to_sci_port(port);
780 	unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
781 	const struct plat_sci_reg *reg;
782 
783 	reg = sci_getreg(port, SCRFDR);
784 	if (reg->size)
785 		return serial_port_in(port, SCRFDR) & fifo_mask;
786 
787 	reg = sci_getreg(port, SCFDR);
788 	if (reg->size)
789 		return serial_port_in(port, SCFDR) & fifo_mask;
790 
791 	return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
792 }
793 
794 /* ********************************************************************** *
795  *                   the interrupt related routines                       *
796  * ********************************************************************** */
797 
798 static void sci_transmit_chars(struct uart_port *port)
799 {
800 	struct circ_buf *xmit = &port->state->xmit;
801 	unsigned int stopped = uart_tx_stopped(port);
802 	unsigned short status;
803 	unsigned short ctrl;
804 	int count;
805 
806 	status = serial_port_in(port, SCxSR);
807 	if (!(status & SCxSR_TDxE(port))) {
808 		ctrl = serial_port_in(port, SCSCR);
809 		if (uart_circ_empty(xmit))
810 			ctrl &= ~SCSCR_TIE;
811 		else
812 			ctrl |= SCSCR_TIE;
813 		serial_port_out(port, SCSCR, ctrl);
814 		return;
815 	}
816 
817 	count = sci_txroom(port);
818 
819 	do {
820 		unsigned char c;
821 
822 		if (port->x_char) {
823 			c = port->x_char;
824 			port->x_char = 0;
825 		} else if (!uart_circ_empty(xmit) && !stopped) {
826 			c = xmit->buf[xmit->tail];
827 			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
828 		} else {
829 			break;
830 		}
831 
832 		serial_port_out(port, SCxTDR, c);
833 
834 		port->icount.tx++;
835 	} while (--count > 0);
836 
837 	sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
838 
839 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
840 		uart_write_wakeup(port);
841 	if (uart_circ_empty(xmit)) {
842 		sci_stop_tx(port);
843 	} else {
844 		ctrl = serial_port_in(port, SCSCR);
845 
846 		if (port->type != PORT_SCI) {
847 			serial_port_in(port, SCxSR); /* Dummy read */
848 			sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
849 		}
850 
851 		ctrl |= SCSCR_TIE;
852 		serial_port_out(port, SCSCR, ctrl);
853 	}
854 }
855 
856 /* On SH3, SCIF may read end-of-break as a space->mark char */
857 #define STEPFN(c)  ({int __c = (c); (((__c-1)|(__c)) == -1); })
858 
859 static void sci_receive_chars(struct uart_port *port)
860 {
861 	struct tty_port *tport = &port->state->port;
862 	int i, count, copied = 0;
863 	unsigned short status;
864 	unsigned char flag;
865 
866 	status = serial_port_in(port, SCxSR);
867 	if (!(status & SCxSR_RDxF(port)))
868 		return;
869 
870 	while (1) {
871 		/* Don't copy more bytes than there is room for in the buffer */
872 		count = tty_buffer_request_room(tport, sci_rxfill(port));
873 
874 		/* If for any reason we can't copy more data, we're done! */
875 		if (count == 0)
876 			break;
877 
878 		if (port->type == PORT_SCI) {
879 			char c = serial_port_in(port, SCxRDR);
880 			if (uart_handle_sysrq_char(port, c))
881 				count = 0;
882 			else
883 				tty_insert_flip_char(tport, c, TTY_NORMAL);
884 		} else {
885 			for (i = 0; i < count; i++) {
886 				char c = serial_port_in(port, SCxRDR);
887 
888 				status = serial_port_in(port, SCxSR);
889 				if (uart_handle_sysrq_char(port, c)) {
890 					count--; i--;
891 					continue;
892 				}
893 
894 				/* Store data and status */
895 				if (status & SCxSR_FER(port)) {
896 					flag = TTY_FRAME;
897 					port->icount.frame++;
898 					dev_notice(port->dev, "frame error\n");
899 				} else if (status & SCxSR_PER(port)) {
900 					flag = TTY_PARITY;
901 					port->icount.parity++;
902 					dev_notice(port->dev, "parity error\n");
903 				} else
904 					flag = TTY_NORMAL;
905 
906 				tty_insert_flip_char(tport, c, flag);
907 			}
908 		}
909 
910 		serial_port_in(port, SCxSR); /* dummy read */
911 		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
912 
913 		copied += count;
914 		port->icount.rx += count;
915 	}
916 
917 	if (copied) {
918 		/* Tell the rest of the system the news. New characters! */
919 		tty_flip_buffer_push(tport);
920 	} else {
921 		/* TTY buffers full; read from RX reg to prevent lockup */
922 		serial_port_in(port, SCxRDR);
923 		serial_port_in(port, SCxSR); /* dummy read */
924 		sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
925 	}
926 }
927 
928 static int sci_handle_errors(struct uart_port *port)
929 {
930 	int copied = 0;
931 	unsigned short status = serial_port_in(port, SCxSR);
932 	struct tty_port *tport = &port->state->port;
933 	struct sci_port *s = to_sci_port(port);
934 
935 	/* Handle overruns */
936 	if (status & s->params->overrun_mask) {
937 		port->icount.overrun++;
938 
939 		/* overrun error */
940 		if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
941 			copied++;
942 
943 		dev_notice(port->dev, "overrun error\n");
944 	}
945 
946 	if (status & SCxSR_FER(port)) {
947 		/* frame error */
948 		port->icount.frame++;
949 
950 		if (tty_insert_flip_char(tport, 0, TTY_FRAME))
951 			copied++;
952 
953 		dev_notice(port->dev, "frame error\n");
954 	}
955 
956 	if (status & SCxSR_PER(port)) {
957 		/* parity error */
958 		port->icount.parity++;
959 
960 		if (tty_insert_flip_char(tport, 0, TTY_PARITY))
961 			copied++;
962 
963 		dev_notice(port->dev, "parity error\n");
964 	}
965 
966 	if (copied)
967 		tty_flip_buffer_push(tport);
968 
969 	return copied;
970 }
971 
972 static int sci_handle_fifo_overrun(struct uart_port *port)
973 {
974 	struct tty_port *tport = &port->state->port;
975 	struct sci_port *s = to_sci_port(port);
976 	const struct plat_sci_reg *reg;
977 	int copied = 0;
978 	u16 status;
979 
980 	reg = sci_getreg(port, s->params->overrun_reg);
981 	if (!reg->size)
982 		return 0;
983 
984 	status = serial_port_in(port, s->params->overrun_reg);
985 	if (status & s->params->overrun_mask) {
986 		status &= ~s->params->overrun_mask;
987 		serial_port_out(port, s->params->overrun_reg, status);
988 
989 		port->icount.overrun++;
990 
991 		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
992 		tty_flip_buffer_push(tport);
993 
994 		dev_dbg(port->dev, "overrun error\n");
995 		copied++;
996 	}
997 
998 	return copied;
999 }
1000 
1001 static int sci_handle_breaks(struct uart_port *port)
1002 {
1003 	int copied = 0;
1004 	unsigned short status = serial_port_in(port, SCxSR);
1005 	struct tty_port *tport = &port->state->port;
1006 
1007 	if (uart_handle_break(port))
1008 		return 0;
1009 
1010 	if (status & SCxSR_BRK(port)) {
1011 		port->icount.brk++;
1012 
1013 		/* Notify of BREAK */
1014 		if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1015 			copied++;
1016 
1017 		dev_dbg(port->dev, "BREAK detected\n");
1018 	}
1019 
1020 	if (copied)
1021 		tty_flip_buffer_push(tport);
1022 
1023 	copied += sci_handle_fifo_overrun(port);
1024 
1025 	return copied;
1026 }
1027 
1028 static int scif_set_rtrg(struct uart_port *port, int rx_trig)
1029 {
1030 	unsigned int bits;
1031 
1032 	if (rx_trig < 1)
1033 		rx_trig = 1;
1034 	if (rx_trig >= port->fifosize)
1035 		rx_trig = port->fifosize;
1036 
1037 	/* HSCIF can be set to an arbitrary level. */
1038 	if (sci_getreg(port, HSRTRGR)->size) {
1039 		serial_port_out(port, HSRTRGR, rx_trig);
1040 		return rx_trig;
1041 	}
1042 
1043 	switch (port->type) {
1044 	case PORT_SCIF:
1045 		if (rx_trig < 4) {
1046 			bits = 0;
1047 			rx_trig = 1;
1048 		} else if (rx_trig < 8) {
1049 			bits = SCFCR_RTRG0;
1050 			rx_trig = 4;
1051 		} else if (rx_trig < 14) {
1052 			bits = SCFCR_RTRG1;
1053 			rx_trig = 8;
1054 		} else {
1055 			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1056 			rx_trig = 14;
1057 		}
1058 		break;
1059 	case PORT_SCIFA:
1060 	case PORT_SCIFB:
1061 		if (rx_trig < 16) {
1062 			bits = 0;
1063 			rx_trig = 1;
1064 		} else if (rx_trig < 32) {
1065 			bits = SCFCR_RTRG0;
1066 			rx_trig = 16;
1067 		} else if (rx_trig < 48) {
1068 			bits = SCFCR_RTRG1;
1069 			rx_trig = 32;
1070 		} else {
1071 			bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1072 			rx_trig = 48;
1073 		}
1074 		break;
1075 	default:
1076 		WARN(1, "unknown FIFO configuration");
1077 		return 1;
1078 	}
1079 
1080 	serial_port_out(port, SCFCR,
1081 		(serial_port_in(port, SCFCR) &
1082 		~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1083 
1084 	return rx_trig;
1085 }
1086 
1087 static int scif_rtrg_enabled(struct uart_port *port)
1088 {
1089 	if (sci_getreg(port, HSRTRGR)->size)
1090 		return serial_port_in(port, HSRTRGR) != 0;
1091 	else
1092 		return (serial_port_in(port, SCFCR) &
1093 			(SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1094 }
1095 
1096 static void rx_fifo_timer_fn(struct timer_list *t)
1097 {
1098 	struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1099 	struct uart_port *port = &s->port;
1100 
1101 	dev_dbg(port->dev, "Rx timed out\n");
1102 	scif_set_rtrg(port, 1);
1103 }
1104 
1105 static ssize_t rx_trigger_show(struct device *dev,
1106 			       struct device_attribute *attr,
1107 			       char *buf)
1108 {
1109 	struct uart_port *port = dev_get_drvdata(dev);
1110 	struct sci_port *sci = to_sci_port(port);
1111 
1112 	return sprintf(buf, "%d\n", sci->rx_trigger);
1113 }
1114 
1115 static ssize_t rx_trigger_store(struct device *dev,
1116 				struct device_attribute *attr,
1117 				const char *buf,
1118 				size_t count)
1119 {
1120 	struct uart_port *port = dev_get_drvdata(dev);
1121 	struct sci_port *sci = to_sci_port(port);
1122 	int ret;
1123 	long r;
1124 
1125 	ret = kstrtol(buf, 0, &r);
1126 	if (ret)
1127 		return ret;
1128 
1129 	sci->rx_trigger = scif_set_rtrg(port, r);
1130 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1131 		scif_set_rtrg(port, 1);
1132 
1133 	return count;
1134 }
1135 
1136 static DEVICE_ATTR(rx_fifo_trigger, 0644, rx_trigger_show, rx_trigger_store);
1137 
1138 static ssize_t rx_fifo_timeout_show(struct device *dev,
1139 			       struct device_attribute *attr,
1140 			       char *buf)
1141 {
1142 	struct uart_port *port = dev_get_drvdata(dev);
1143 	struct sci_port *sci = to_sci_port(port);
1144 	int v;
1145 
1146 	if (port->type == PORT_HSCIF)
1147 		v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1148 	else
1149 		v = sci->rx_fifo_timeout;
1150 
1151 	return sprintf(buf, "%d\n", v);
1152 }
1153 
1154 static ssize_t rx_fifo_timeout_store(struct device *dev,
1155 				struct device_attribute *attr,
1156 				const char *buf,
1157 				size_t count)
1158 {
1159 	struct uart_port *port = dev_get_drvdata(dev);
1160 	struct sci_port *sci = to_sci_port(port);
1161 	int ret;
1162 	long r;
1163 
1164 	ret = kstrtol(buf, 0, &r);
1165 	if (ret)
1166 		return ret;
1167 
1168 	if (port->type == PORT_HSCIF) {
1169 		if (r < 0 || r > 3)
1170 			return -EINVAL;
1171 		sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1172 	} else {
1173 		sci->rx_fifo_timeout = r;
1174 		scif_set_rtrg(port, 1);
1175 		if (r > 0)
1176 			timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1177 	}
1178 
1179 	return count;
1180 }
1181 
1182 static DEVICE_ATTR_RW(rx_fifo_timeout);
1183 
1184 
1185 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1186 static void sci_dma_tx_complete(void *arg)
1187 {
1188 	struct sci_port *s = arg;
1189 	struct uart_port *port = &s->port;
1190 	struct circ_buf *xmit = &port->state->xmit;
1191 	unsigned long flags;
1192 
1193 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1194 
1195 	spin_lock_irqsave(&port->lock, flags);
1196 
1197 	xmit->tail += s->tx_dma_len;
1198 	xmit->tail &= UART_XMIT_SIZE - 1;
1199 
1200 	port->icount.tx += s->tx_dma_len;
1201 
1202 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1203 		uart_write_wakeup(port);
1204 
1205 	if (!uart_circ_empty(xmit)) {
1206 		s->cookie_tx = 0;
1207 		schedule_work(&s->work_tx);
1208 	} else {
1209 		s->cookie_tx = -EINVAL;
1210 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1211 			u16 ctrl = serial_port_in(port, SCSCR);
1212 			serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1213 		}
1214 	}
1215 
1216 	spin_unlock_irqrestore(&port->lock, flags);
1217 }
1218 
1219 /* Locking: called with port lock held */
1220 static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1221 {
1222 	struct uart_port *port = &s->port;
1223 	struct tty_port *tport = &port->state->port;
1224 	int copied;
1225 
1226 	copied = tty_insert_flip_string(tport, buf, count);
1227 	if (copied < count)
1228 		port->icount.buf_overrun++;
1229 
1230 	port->icount.rx += copied;
1231 
1232 	return copied;
1233 }
1234 
1235 static int sci_dma_rx_find_active(struct sci_port *s)
1236 {
1237 	unsigned int i;
1238 
1239 	for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1240 		if (s->active_rx == s->cookie_rx[i])
1241 			return i;
1242 
1243 	return -1;
1244 }
1245 
1246 static void sci_rx_dma_release(struct sci_port *s)
1247 {
1248 	struct dma_chan *chan = s->chan_rx_saved;
1249 
1250 	s->chan_rx_saved = s->chan_rx = NULL;
1251 	s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1252 	dmaengine_terminate_sync(chan);
1253 	dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1254 			  sg_dma_address(&s->sg_rx[0]));
1255 	dma_release_channel(chan);
1256 }
1257 
1258 static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1259 {
1260 	long sec = usec / 1000000;
1261 	long nsec = (usec % 1000000) * 1000;
1262 	ktime_t t = ktime_set(sec, nsec);
1263 
1264 	hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1265 }
1266 
1267 static void sci_dma_rx_complete(void *arg)
1268 {
1269 	struct sci_port *s = arg;
1270 	struct dma_chan *chan = s->chan_rx;
1271 	struct uart_port *port = &s->port;
1272 	struct dma_async_tx_descriptor *desc;
1273 	unsigned long flags;
1274 	int active, count = 0;
1275 
1276 	dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1277 		s->active_rx);
1278 
1279 	spin_lock_irqsave(&port->lock, flags);
1280 
1281 	active = sci_dma_rx_find_active(s);
1282 	if (active >= 0)
1283 		count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1284 
1285 	start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1286 
1287 	if (count)
1288 		tty_flip_buffer_push(&port->state->port);
1289 
1290 	desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1291 				       DMA_DEV_TO_MEM,
1292 				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1293 	if (!desc)
1294 		goto fail;
1295 
1296 	desc->callback = sci_dma_rx_complete;
1297 	desc->callback_param = s;
1298 	s->cookie_rx[active] = dmaengine_submit(desc);
1299 	if (dma_submit_error(s->cookie_rx[active]))
1300 		goto fail;
1301 
1302 	s->active_rx = s->cookie_rx[!active];
1303 
1304 	dma_async_issue_pending(chan);
1305 
1306 	spin_unlock_irqrestore(&port->lock, flags);
1307 	dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1308 		__func__, s->cookie_rx[active], active, s->active_rx);
1309 	return;
1310 
1311 fail:
1312 	spin_unlock_irqrestore(&port->lock, flags);
1313 	dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1314 	/* Switch to PIO */
1315 	spin_lock_irqsave(&port->lock, flags);
1316 	s->chan_rx = NULL;
1317 	sci_start_rx(port);
1318 	spin_unlock_irqrestore(&port->lock, flags);
1319 }
1320 
1321 static void sci_tx_dma_release(struct sci_port *s)
1322 {
1323 	struct dma_chan *chan = s->chan_tx_saved;
1324 
1325 	cancel_work_sync(&s->work_tx);
1326 	s->chan_tx_saved = s->chan_tx = NULL;
1327 	s->cookie_tx = -EINVAL;
1328 	dmaengine_terminate_sync(chan);
1329 	dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1330 			 DMA_TO_DEVICE);
1331 	dma_release_channel(chan);
1332 }
1333 
1334 static int sci_submit_rx(struct sci_port *s, bool port_lock_held)
1335 {
1336 	struct dma_chan *chan = s->chan_rx;
1337 	struct uart_port *port = &s->port;
1338 	unsigned long flags;
1339 	int i;
1340 
1341 	for (i = 0; i < 2; i++) {
1342 		struct scatterlist *sg = &s->sg_rx[i];
1343 		struct dma_async_tx_descriptor *desc;
1344 
1345 		desc = dmaengine_prep_slave_sg(chan,
1346 			sg, 1, DMA_DEV_TO_MEM,
1347 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1348 		if (!desc)
1349 			goto fail;
1350 
1351 		desc->callback = sci_dma_rx_complete;
1352 		desc->callback_param = s;
1353 		s->cookie_rx[i] = dmaengine_submit(desc);
1354 		if (dma_submit_error(s->cookie_rx[i]))
1355 			goto fail;
1356 
1357 	}
1358 
1359 	s->active_rx = s->cookie_rx[0];
1360 
1361 	dma_async_issue_pending(chan);
1362 	return 0;
1363 
1364 fail:
1365 	/* Switch to PIO */
1366 	if (!port_lock_held)
1367 		spin_lock_irqsave(&port->lock, flags);
1368 	if (i)
1369 		dmaengine_terminate_async(chan);
1370 	for (i = 0; i < 2; i++)
1371 		s->cookie_rx[i] = -EINVAL;
1372 	s->active_rx = 0;
1373 	s->chan_rx = NULL;
1374 	sci_start_rx(port);
1375 	if (!port_lock_held)
1376 		spin_unlock_irqrestore(&port->lock, flags);
1377 	return -EAGAIN;
1378 }
1379 
1380 static void work_fn_tx(struct work_struct *work)
1381 {
1382 	struct sci_port *s = container_of(work, struct sci_port, work_tx);
1383 	struct dma_async_tx_descriptor *desc;
1384 	struct dma_chan *chan = s->chan_tx;
1385 	struct uart_port *port = &s->port;
1386 	struct circ_buf *xmit = &port->state->xmit;
1387 	unsigned long flags;
1388 	dma_addr_t buf;
1389 
1390 	/*
1391 	 * DMA is idle now.
1392 	 * Port xmit buffer is already mapped, and it is one page... Just adjust
1393 	 * offsets and lengths. Since it is a circular buffer, we have to
1394 	 * transmit till the end, and then the rest. Take the port lock to get a
1395 	 * consistent xmit buffer state.
1396 	 */
1397 	spin_lock_irq(&port->lock);
1398 	buf = s->tx_dma_addr + (xmit->tail & (UART_XMIT_SIZE - 1));
1399 	s->tx_dma_len = min_t(unsigned int,
1400 		CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1401 		CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1402 	spin_unlock_irq(&port->lock);
1403 
1404 	desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1405 					   DMA_MEM_TO_DEV,
1406 					   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1407 	if (!desc) {
1408 		dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1409 		goto switch_to_pio;
1410 	}
1411 
1412 	dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1413 				   DMA_TO_DEVICE);
1414 
1415 	spin_lock_irq(&port->lock);
1416 	desc->callback = sci_dma_tx_complete;
1417 	desc->callback_param = s;
1418 	spin_unlock_irq(&port->lock);
1419 	s->cookie_tx = dmaengine_submit(desc);
1420 	if (dma_submit_error(s->cookie_tx)) {
1421 		dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1422 		goto switch_to_pio;
1423 	}
1424 
1425 	dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1426 		__func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1427 
1428 	dma_async_issue_pending(chan);
1429 	return;
1430 
1431 switch_to_pio:
1432 	spin_lock_irqsave(&port->lock, flags);
1433 	s->chan_tx = NULL;
1434 	sci_start_tx(port);
1435 	spin_unlock_irqrestore(&port->lock, flags);
1436 	return;
1437 }
1438 
1439 static enum hrtimer_restart rx_timer_fn(struct hrtimer *t)
1440 {
1441 	struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1442 	struct dma_chan *chan = s->chan_rx;
1443 	struct uart_port *port = &s->port;
1444 	struct dma_tx_state state;
1445 	enum dma_status status;
1446 	unsigned long flags;
1447 	unsigned int read;
1448 	int active, count;
1449 	u16 scr;
1450 
1451 	dev_dbg(port->dev, "DMA Rx timed out\n");
1452 
1453 	spin_lock_irqsave(&port->lock, flags);
1454 
1455 	active = sci_dma_rx_find_active(s);
1456 	if (active < 0) {
1457 		spin_unlock_irqrestore(&port->lock, flags);
1458 		return HRTIMER_NORESTART;
1459 	}
1460 
1461 	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1462 	if (status == DMA_COMPLETE) {
1463 		spin_unlock_irqrestore(&port->lock, flags);
1464 		dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1465 			s->active_rx, active);
1466 
1467 		/* Let packet complete handler take care of the packet */
1468 		return HRTIMER_NORESTART;
1469 	}
1470 
1471 	dmaengine_pause(chan);
1472 
1473 	/*
1474 	 * sometimes DMA transfer doesn't stop even if it is stopped and
1475 	 * data keeps on coming until transaction is complete so check
1476 	 * for DMA_COMPLETE again
1477 	 * Let packet complete handler take care of the packet
1478 	 */
1479 	status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1480 	if (status == DMA_COMPLETE) {
1481 		spin_unlock_irqrestore(&port->lock, flags);
1482 		dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1483 		return HRTIMER_NORESTART;
1484 	}
1485 
1486 	/* Handle incomplete DMA receive */
1487 	dmaengine_terminate_async(s->chan_rx);
1488 	read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1489 
1490 	if (read) {
1491 		count = sci_dma_rx_push(s, s->rx_buf[active], read);
1492 		if (count)
1493 			tty_flip_buffer_push(&port->state->port);
1494 	}
1495 
1496 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1497 		sci_submit_rx(s, true);
1498 
1499 	/* Direct new serial port interrupts back to CPU */
1500 	scr = serial_port_in(port, SCSCR);
1501 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1502 		scr &= ~SCSCR_RDRQE;
1503 		enable_irq(s->irqs[SCIx_RXI_IRQ]);
1504 	}
1505 	serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1506 
1507 	spin_unlock_irqrestore(&port->lock, flags);
1508 
1509 	return HRTIMER_NORESTART;
1510 }
1511 
1512 static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1513 					     enum dma_transfer_direction dir)
1514 {
1515 	struct dma_chan *chan;
1516 	struct dma_slave_config cfg;
1517 	int ret;
1518 
1519 	chan = dma_request_slave_channel(port->dev,
1520 					 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1521 	if (!chan) {
1522 		dev_dbg(port->dev, "dma_request_slave_channel failed\n");
1523 		return NULL;
1524 	}
1525 
1526 	memset(&cfg, 0, sizeof(cfg));
1527 	cfg.direction = dir;
1528 	if (dir == DMA_MEM_TO_DEV) {
1529 		cfg.dst_addr = port->mapbase +
1530 			(sci_getreg(port, SCxTDR)->offset << port->regshift);
1531 		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1532 	} else {
1533 		cfg.src_addr = port->mapbase +
1534 			(sci_getreg(port, SCxRDR)->offset << port->regshift);
1535 		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1536 	}
1537 
1538 	ret = dmaengine_slave_config(chan, &cfg);
1539 	if (ret) {
1540 		dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1541 		dma_release_channel(chan);
1542 		return NULL;
1543 	}
1544 
1545 	return chan;
1546 }
1547 
1548 static void sci_request_dma(struct uart_port *port)
1549 {
1550 	struct sci_port *s = to_sci_port(port);
1551 	struct dma_chan *chan;
1552 
1553 	dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1554 
1555 	if (!port->dev->of_node)
1556 		return;
1557 
1558 	s->cookie_tx = -EINVAL;
1559 
1560 	/*
1561 	 * Don't request a dma channel if no channel was specified
1562 	 * in the device tree.
1563 	 */
1564 	if (!of_find_property(port->dev->of_node, "dmas", NULL))
1565 		return;
1566 
1567 	chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1568 	dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1569 	if (chan) {
1570 		/* UART circular tx buffer is an aligned page. */
1571 		s->tx_dma_addr = dma_map_single(chan->device->dev,
1572 						port->state->xmit.buf,
1573 						UART_XMIT_SIZE,
1574 						DMA_TO_DEVICE);
1575 		if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1576 			dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1577 			dma_release_channel(chan);
1578 		} else {
1579 			dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1580 				__func__, UART_XMIT_SIZE,
1581 				port->state->xmit.buf, &s->tx_dma_addr);
1582 
1583 			INIT_WORK(&s->work_tx, work_fn_tx);
1584 			s->chan_tx_saved = s->chan_tx = chan;
1585 		}
1586 	}
1587 
1588 	chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1589 	dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1590 	if (chan) {
1591 		unsigned int i;
1592 		dma_addr_t dma;
1593 		void *buf;
1594 
1595 		s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1596 		buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1597 					 &dma, GFP_KERNEL);
1598 		if (!buf) {
1599 			dev_warn(port->dev,
1600 				 "Failed to allocate Rx dma buffer, using PIO\n");
1601 			dma_release_channel(chan);
1602 			return;
1603 		}
1604 
1605 		for (i = 0; i < 2; i++) {
1606 			struct scatterlist *sg = &s->sg_rx[i];
1607 
1608 			sg_init_table(sg, 1);
1609 			s->rx_buf[i] = buf;
1610 			sg_dma_address(sg) = dma;
1611 			sg_dma_len(sg) = s->buf_len_rx;
1612 
1613 			buf += s->buf_len_rx;
1614 			dma += s->buf_len_rx;
1615 		}
1616 
1617 		hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1618 		s->rx_timer.function = rx_timer_fn;
1619 
1620 		s->chan_rx_saved = s->chan_rx = chan;
1621 
1622 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1623 			sci_submit_rx(s, false);
1624 	}
1625 }
1626 
1627 static void sci_free_dma(struct uart_port *port)
1628 {
1629 	struct sci_port *s = to_sci_port(port);
1630 
1631 	if (s->chan_tx_saved)
1632 		sci_tx_dma_release(s);
1633 	if (s->chan_rx_saved)
1634 		sci_rx_dma_release(s);
1635 }
1636 
1637 static void sci_flush_buffer(struct uart_port *port)
1638 {
1639 	/*
1640 	 * In uart_flush_buffer(), the xmit circular buffer has just been
1641 	 * cleared, so we have to reset tx_dma_len accordingly.
1642 	 */
1643 	to_sci_port(port)->tx_dma_len = 0;
1644 }
1645 #else /* !CONFIG_SERIAL_SH_SCI_DMA */
1646 static inline void sci_request_dma(struct uart_port *port)
1647 {
1648 }
1649 
1650 static inline void sci_free_dma(struct uart_port *port)
1651 {
1652 }
1653 
1654 #define sci_flush_buffer	NULL
1655 #endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1656 
1657 static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1658 {
1659 	struct uart_port *port = ptr;
1660 	struct sci_port *s = to_sci_port(port);
1661 
1662 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1663 	if (s->chan_rx) {
1664 		u16 scr = serial_port_in(port, SCSCR);
1665 		u16 ssr = serial_port_in(port, SCxSR);
1666 
1667 		/* Disable future Rx interrupts */
1668 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1669 			disable_irq_nosync(irq);
1670 			scr |= SCSCR_RDRQE;
1671 		} else {
1672 			if (sci_submit_rx(s, false) < 0)
1673 				goto handle_pio;
1674 
1675 			scr &= ~SCSCR_RIE;
1676 		}
1677 		serial_port_out(port, SCSCR, scr);
1678 		/* Clear current interrupt */
1679 		serial_port_out(port, SCxSR,
1680 				ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1681 		dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1682 			jiffies, s->rx_timeout);
1683 		start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1684 
1685 		return IRQ_HANDLED;
1686 	}
1687 
1688 handle_pio:
1689 #endif
1690 
1691 	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1692 		if (!scif_rtrg_enabled(port))
1693 			scif_set_rtrg(port, s->rx_trigger);
1694 
1695 		mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1696 			  s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1697 	}
1698 
1699 	/* I think sci_receive_chars has to be called irrespective
1700 	 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1701 	 * to be disabled?
1702 	 */
1703 	sci_receive_chars(port);
1704 
1705 	return IRQ_HANDLED;
1706 }
1707 
1708 static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1709 {
1710 	struct uart_port *port = ptr;
1711 	unsigned long flags;
1712 
1713 	spin_lock_irqsave(&port->lock, flags);
1714 	sci_transmit_chars(port);
1715 	spin_unlock_irqrestore(&port->lock, flags);
1716 
1717 	return IRQ_HANDLED;
1718 }
1719 
1720 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1721 {
1722 	struct uart_port *port = ptr;
1723 
1724 	/* Handle BREAKs */
1725 	sci_handle_breaks(port);
1726 	sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1727 
1728 	return IRQ_HANDLED;
1729 }
1730 
1731 static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1732 {
1733 	struct uart_port *port = ptr;
1734 	struct sci_port *s = to_sci_port(port);
1735 
1736 	if (s->irqs[SCIx_ERI_IRQ] == s->irqs[SCIx_BRI_IRQ]) {
1737 		/* Break and Error interrupts are muxed */
1738 		unsigned short ssr_status = serial_port_in(port, SCxSR);
1739 
1740 		/* Break Interrupt */
1741 		if (ssr_status & SCxSR_BRK(port))
1742 			sci_br_interrupt(irq, ptr);
1743 
1744 		/* Break only? */
1745 		if (!(ssr_status & SCxSR_ERRORS(port)))
1746 			return IRQ_HANDLED;
1747 	}
1748 
1749 	/* Handle errors */
1750 	if (port->type == PORT_SCI) {
1751 		if (sci_handle_errors(port)) {
1752 			/* discard character in rx buffer */
1753 			serial_port_in(port, SCxSR);
1754 			sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1755 		}
1756 	} else {
1757 		sci_handle_fifo_overrun(port);
1758 		if (!s->chan_rx)
1759 			sci_receive_chars(port);
1760 	}
1761 
1762 	sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1763 
1764 	/* Kick the transmission */
1765 	if (!s->chan_tx)
1766 		sci_tx_interrupt(irq, ptr);
1767 
1768 	return IRQ_HANDLED;
1769 }
1770 
1771 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1772 {
1773 	unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1774 	struct uart_port *port = ptr;
1775 	struct sci_port *s = to_sci_port(port);
1776 	irqreturn_t ret = IRQ_NONE;
1777 
1778 	ssr_status = serial_port_in(port, SCxSR);
1779 	scr_status = serial_port_in(port, SCSCR);
1780 	if (s->params->overrun_reg == SCxSR)
1781 		orer_status = ssr_status;
1782 	else if (sci_getreg(port, s->params->overrun_reg)->size)
1783 		orer_status = serial_port_in(port, s->params->overrun_reg);
1784 
1785 	err_enabled = scr_status & port_rx_irq_mask(port);
1786 
1787 	/* Tx Interrupt */
1788 	if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1789 	    !s->chan_tx)
1790 		ret = sci_tx_interrupt(irq, ptr);
1791 
1792 	/*
1793 	 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1794 	 * DR flags
1795 	 */
1796 	if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1797 	    (scr_status & SCSCR_RIE))
1798 		ret = sci_rx_interrupt(irq, ptr);
1799 
1800 	/* Error Interrupt */
1801 	if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1802 		ret = sci_er_interrupt(irq, ptr);
1803 
1804 	/* Break Interrupt */
1805 	if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1806 		ret = sci_br_interrupt(irq, ptr);
1807 
1808 	/* Overrun Interrupt */
1809 	if (orer_status & s->params->overrun_mask) {
1810 		sci_handle_fifo_overrun(port);
1811 		ret = IRQ_HANDLED;
1812 	}
1813 
1814 	return ret;
1815 }
1816 
1817 static const struct sci_irq_desc {
1818 	const char	*desc;
1819 	irq_handler_t	handler;
1820 } sci_irq_desc[] = {
1821 	/*
1822 	 * Split out handlers, the default case.
1823 	 */
1824 	[SCIx_ERI_IRQ] = {
1825 		.desc = "rx err",
1826 		.handler = sci_er_interrupt,
1827 	},
1828 
1829 	[SCIx_RXI_IRQ] = {
1830 		.desc = "rx full",
1831 		.handler = sci_rx_interrupt,
1832 	},
1833 
1834 	[SCIx_TXI_IRQ] = {
1835 		.desc = "tx empty",
1836 		.handler = sci_tx_interrupt,
1837 	},
1838 
1839 	[SCIx_BRI_IRQ] = {
1840 		.desc = "break",
1841 		.handler = sci_br_interrupt,
1842 	},
1843 
1844 	[SCIx_DRI_IRQ] = {
1845 		.desc = "rx ready",
1846 		.handler = sci_rx_interrupt,
1847 	},
1848 
1849 	[SCIx_TEI_IRQ] = {
1850 		.desc = "tx end",
1851 		.handler = sci_tx_interrupt,
1852 	},
1853 
1854 	/*
1855 	 * Special muxed handler.
1856 	 */
1857 	[SCIx_MUX_IRQ] = {
1858 		.desc = "mux",
1859 		.handler = sci_mpxed_interrupt,
1860 	},
1861 };
1862 
1863 static int sci_request_irq(struct sci_port *port)
1864 {
1865 	struct uart_port *up = &port->port;
1866 	int i, j, w, ret = 0;
1867 
1868 	for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1869 		const struct sci_irq_desc *desc;
1870 		int irq;
1871 
1872 		/* Check if already registered (muxed) */
1873 		for (w = 0; w < i; w++)
1874 			if (port->irqs[w] == port->irqs[i])
1875 				w = i + 1;
1876 		if (w > i)
1877 			continue;
1878 
1879 		if (SCIx_IRQ_IS_MUXED(port)) {
1880 			i = SCIx_MUX_IRQ;
1881 			irq = up->irq;
1882 		} else {
1883 			irq = port->irqs[i];
1884 
1885 			/*
1886 			 * Certain port types won't support all of the
1887 			 * available interrupt sources.
1888 			 */
1889 			if (unlikely(irq < 0))
1890 				continue;
1891 		}
1892 
1893 		desc = sci_irq_desc + i;
1894 		port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1895 					    dev_name(up->dev), desc->desc);
1896 		if (!port->irqstr[j]) {
1897 			ret = -ENOMEM;
1898 			goto out_nomem;
1899 		}
1900 
1901 		ret = request_irq(irq, desc->handler, up->irqflags,
1902 				  port->irqstr[j], port);
1903 		if (unlikely(ret)) {
1904 			dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1905 			goto out_noirq;
1906 		}
1907 	}
1908 
1909 	return 0;
1910 
1911 out_noirq:
1912 	while (--i >= 0)
1913 		free_irq(port->irqs[i], port);
1914 
1915 out_nomem:
1916 	while (--j >= 0)
1917 		kfree(port->irqstr[j]);
1918 
1919 	return ret;
1920 }
1921 
1922 static void sci_free_irq(struct sci_port *port)
1923 {
1924 	int i;
1925 
1926 	/*
1927 	 * Intentionally in reverse order so we iterate over the muxed
1928 	 * IRQ first.
1929 	 */
1930 	for (i = 0; i < SCIx_NR_IRQS; i++) {
1931 		int irq = port->irqs[i];
1932 
1933 		/*
1934 		 * Certain port types won't support all of the available
1935 		 * interrupt sources.
1936 		 */
1937 		if (unlikely(irq < 0))
1938 			continue;
1939 
1940 		free_irq(port->irqs[i], port);
1941 		kfree(port->irqstr[i]);
1942 
1943 		if (SCIx_IRQ_IS_MUXED(port)) {
1944 			/* If there's only one IRQ, we're done. */
1945 			return;
1946 		}
1947 	}
1948 }
1949 
1950 static unsigned int sci_tx_empty(struct uart_port *port)
1951 {
1952 	unsigned short status = serial_port_in(port, SCxSR);
1953 	unsigned short in_tx_fifo = sci_txfill(port);
1954 
1955 	return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1956 }
1957 
1958 static void sci_set_rts(struct uart_port *port, bool state)
1959 {
1960 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1961 		u16 data = serial_port_in(port, SCPDR);
1962 
1963 		/* Active low */
1964 		if (state)
1965 			data &= ~SCPDR_RTSD;
1966 		else
1967 			data |= SCPDR_RTSD;
1968 		serial_port_out(port, SCPDR, data);
1969 
1970 		/* RTS# is output */
1971 		serial_port_out(port, SCPCR,
1972 				serial_port_in(port, SCPCR) | SCPCR_RTSC);
1973 	} else if (sci_getreg(port, SCSPTR)->size) {
1974 		u16 ctrl = serial_port_in(port, SCSPTR);
1975 
1976 		/* Active low */
1977 		if (state)
1978 			ctrl &= ~SCSPTR_RTSDT;
1979 		else
1980 			ctrl |= SCSPTR_RTSDT;
1981 		serial_port_out(port, SCSPTR, ctrl);
1982 	}
1983 }
1984 
1985 static bool sci_get_cts(struct uart_port *port)
1986 {
1987 	if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1988 		/* Active low */
1989 		return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
1990 	} else if (sci_getreg(port, SCSPTR)->size) {
1991 		/* Active low */
1992 		return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
1993 	}
1994 
1995 	return true;
1996 }
1997 
1998 /*
1999  * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
2000  * CTS/RTS is supported in hardware by at least one port and controlled
2001  * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
2002  * handled via the ->init_pins() op, which is a bit of a one-way street,
2003  * lacking any ability to defer pin control -- this will later be
2004  * converted over to the GPIO framework).
2005  *
2006  * Other modes (such as loopback) are supported generically on certain
2007  * port types, but not others. For these it's sufficient to test for the
2008  * existence of the support register and simply ignore the port type.
2009  */
2010 static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
2011 {
2012 	struct sci_port *s = to_sci_port(port);
2013 
2014 	if (mctrl & TIOCM_LOOP) {
2015 		const struct plat_sci_reg *reg;
2016 
2017 		/*
2018 		 * Standard loopback mode for SCFCR ports.
2019 		 */
2020 		reg = sci_getreg(port, SCFCR);
2021 		if (reg->size)
2022 			serial_port_out(port, SCFCR,
2023 					serial_port_in(port, SCFCR) |
2024 					SCFCR_LOOP);
2025 	}
2026 
2027 	mctrl_gpio_set(s->gpios, mctrl);
2028 
2029 	if (!s->has_rtscts)
2030 		return;
2031 
2032 	if (!(mctrl & TIOCM_RTS)) {
2033 		/* Disable Auto RTS */
2034 		serial_port_out(port, SCFCR,
2035 				serial_port_in(port, SCFCR) & ~SCFCR_MCE);
2036 
2037 		/* Clear RTS */
2038 		sci_set_rts(port, 0);
2039 	} else if (s->autorts) {
2040 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2041 			/* Enable RTS# pin function */
2042 			serial_port_out(port, SCPCR,
2043 				serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
2044 		}
2045 
2046 		/* Enable Auto RTS */
2047 		serial_port_out(port, SCFCR,
2048 				serial_port_in(port, SCFCR) | SCFCR_MCE);
2049 	} else {
2050 		/* Set RTS */
2051 		sci_set_rts(port, 1);
2052 	}
2053 }
2054 
2055 static unsigned int sci_get_mctrl(struct uart_port *port)
2056 {
2057 	struct sci_port *s = to_sci_port(port);
2058 	struct mctrl_gpios *gpios = s->gpios;
2059 	unsigned int mctrl = 0;
2060 
2061 	mctrl_gpio_get(gpios, &mctrl);
2062 
2063 	/*
2064 	 * CTS/RTS is handled in hardware when supported, while nothing
2065 	 * else is wired up.
2066 	 */
2067 	if (s->autorts) {
2068 		if (sci_get_cts(port))
2069 			mctrl |= TIOCM_CTS;
2070 	} else if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS))) {
2071 		mctrl |= TIOCM_CTS;
2072 	}
2073 	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR)))
2074 		mctrl |= TIOCM_DSR;
2075 	if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD)))
2076 		mctrl |= TIOCM_CAR;
2077 
2078 	return mctrl;
2079 }
2080 
2081 static void sci_enable_ms(struct uart_port *port)
2082 {
2083 	mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2084 }
2085 
2086 static void sci_break_ctl(struct uart_port *port, int break_state)
2087 {
2088 	unsigned short scscr, scsptr;
2089 	unsigned long flags;
2090 
2091 	/* check wheter the port has SCSPTR */
2092 	if (!sci_getreg(port, SCSPTR)->size) {
2093 		/*
2094 		 * Not supported by hardware. Most parts couple break and rx
2095 		 * interrupts together, with break detection always enabled.
2096 		 */
2097 		return;
2098 	}
2099 
2100 	spin_lock_irqsave(&port->lock, flags);
2101 	scsptr = serial_port_in(port, SCSPTR);
2102 	scscr = serial_port_in(port, SCSCR);
2103 
2104 	if (break_state == -1) {
2105 		scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2106 		scscr &= ~SCSCR_TE;
2107 	} else {
2108 		scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2109 		scscr |= SCSCR_TE;
2110 	}
2111 
2112 	serial_port_out(port, SCSPTR, scsptr);
2113 	serial_port_out(port, SCSCR, scscr);
2114 	spin_unlock_irqrestore(&port->lock, flags);
2115 }
2116 
2117 static int sci_startup(struct uart_port *port)
2118 {
2119 	struct sci_port *s = to_sci_port(port);
2120 	int ret;
2121 
2122 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2123 
2124 	sci_request_dma(port);
2125 
2126 	ret = sci_request_irq(s);
2127 	if (unlikely(ret < 0)) {
2128 		sci_free_dma(port);
2129 		return ret;
2130 	}
2131 
2132 	return 0;
2133 }
2134 
2135 static void sci_shutdown(struct uart_port *port)
2136 {
2137 	struct sci_port *s = to_sci_port(port);
2138 	unsigned long flags;
2139 	u16 scr;
2140 
2141 	dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2142 
2143 	s->autorts = false;
2144 	mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2145 
2146 	spin_lock_irqsave(&port->lock, flags);
2147 	sci_stop_rx(port);
2148 	sci_stop_tx(port);
2149 	/*
2150 	 * Stop RX and TX, disable related interrupts, keep clock source
2151 	 * and HSCIF TOT bits
2152 	 */
2153 	scr = serial_port_in(port, SCSCR);
2154 	serial_port_out(port, SCSCR, scr &
2155 			(SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2156 	spin_unlock_irqrestore(&port->lock, flags);
2157 
2158 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2159 	if (s->chan_rx_saved) {
2160 		dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2161 			port->line);
2162 		hrtimer_cancel(&s->rx_timer);
2163 	}
2164 #endif
2165 
2166 	if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
2167 		del_timer_sync(&s->rx_fifo_timer);
2168 	sci_free_irq(s);
2169 	sci_free_dma(port);
2170 }
2171 
2172 static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2173 			unsigned int *srr)
2174 {
2175 	unsigned long freq = s->clk_rates[SCI_SCK];
2176 	int err, min_err = INT_MAX;
2177 	unsigned int sr;
2178 
2179 	if (s->port.type != PORT_HSCIF)
2180 		freq *= 2;
2181 
2182 	for_each_sr(sr, s) {
2183 		err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2184 		if (abs(err) >= abs(min_err))
2185 			continue;
2186 
2187 		min_err = err;
2188 		*srr = sr - 1;
2189 
2190 		if (!err)
2191 			break;
2192 	}
2193 
2194 	dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2195 		*srr + 1);
2196 	return min_err;
2197 }
2198 
2199 static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2200 			unsigned long freq, unsigned int *dlr,
2201 			unsigned int *srr)
2202 {
2203 	int err, min_err = INT_MAX;
2204 	unsigned int sr, dl;
2205 
2206 	if (s->port.type != PORT_HSCIF)
2207 		freq *= 2;
2208 
2209 	for_each_sr(sr, s) {
2210 		dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2211 		dl = clamp(dl, 1U, 65535U);
2212 
2213 		err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2214 		if (abs(err) >= abs(min_err))
2215 			continue;
2216 
2217 		min_err = err;
2218 		*dlr = dl;
2219 		*srr = sr - 1;
2220 
2221 		if (!err)
2222 			break;
2223 	}
2224 
2225 	dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2226 		min_err, *dlr, *srr + 1);
2227 	return min_err;
2228 }
2229 
2230 /* calculate sample rate, BRR, and clock select */
2231 static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2232 			  unsigned int *brr, unsigned int *srr,
2233 			  unsigned int *cks)
2234 {
2235 	unsigned long freq = s->clk_rates[SCI_FCK];
2236 	unsigned int sr, br, prediv, scrate, c;
2237 	int err, min_err = INT_MAX;
2238 
2239 	if (s->port.type != PORT_HSCIF)
2240 		freq *= 2;
2241 
2242 	/*
2243 	 * Find the combination of sample rate and clock select with the
2244 	 * smallest deviation from the desired baud rate.
2245 	 * Prefer high sample rates to maximise the receive margin.
2246 	 *
2247 	 * M: Receive margin (%)
2248 	 * N: Ratio of bit rate to clock (N = sampling rate)
2249 	 * D: Clock duty (D = 0 to 1.0)
2250 	 * L: Frame length (L = 9 to 12)
2251 	 * F: Absolute value of clock frequency deviation
2252 	 *
2253 	 *  M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2254 	 *      (|D - 0.5| / N * (1 + F))|
2255 	 *  NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2256 	 */
2257 	for_each_sr(sr, s) {
2258 		for (c = 0; c <= 3; c++) {
2259 			/* integerized formulas from HSCIF documentation */
2260 			prediv = sr * (1 << (2 * c + 1));
2261 
2262 			/*
2263 			 * We need to calculate:
2264 			 *
2265 			 *     br = freq / (prediv * bps) clamped to [1..256]
2266 			 *     err = freq / (br * prediv) - bps
2267 			 *
2268 			 * Watch out for overflow when calculating the desired
2269 			 * sampling clock rate!
2270 			 */
2271 			if (bps > UINT_MAX / prediv)
2272 				break;
2273 
2274 			scrate = prediv * bps;
2275 			br = DIV_ROUND_CLOSEST(freq, scrate);
2276 			br = clamp(br, 1U, 256U);
2277 
2278 			err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2279 			if (abs(err) >= abs(min_err))
2280 				continue;
2281 
2282 			min_err = err;
2283 			*brr = br - 1;
2284 			*srr = sr - 1;
2285 			*cks = c;
2286 
2287 			if (!err)
2288 				goto found;
2289 		}
2290 	}
2291 
2292 found:
2293 	dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2294 		min_err, *brr, *srr + 1, *cks);
2295 	return min_err;
2296 }
2297 
2298 static void sci_reset(struct uart_port *port)
2299 {
2300 	const struct plat_sci_reg *reg;
2301 	unsigned int status;
2302 	struct sci_port *s = to_sci_port(port);
2303 
2304 	serial_port_out(port, SCSCR, s->hscif_tot);	/* TE=0, RE=0, CKE1=0 */
2305 
2306 	reg = sci_getreg(port, SCFCR);
2307 	if (reg->size)
2308 		serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2309 
2310 	sci_clear_SCxSR(port,
2311 			SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2312 			SCxSR_BREAK_CLEAR(port));
2313 	if (sci_getreg(port, SCLSR)->size) {
2314 		status = serial_port_in(port, SCLSR);
2315 		status &= ~(SCLSR_TO | SCLSR_ORER);
2316 		serial_port_out(port, SCLSR, status);
2317 	}
2318 
2319 	if (s->rx_trigger > 1) {
2320 		if (s->rx_fifo_timeout) {
2321 			scif_set_rtrg(port, 1);
2322 			timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2323 		} else {
2324 			if (port->type == PORT_SCIFA ||
2325 			    port->type == PORT_SCIFB)
2326 				scif_set_rtrg(port, 1);
2327 			else
2328 				scif_set_rtrg(port, s->rx_trigger);
2329 		}
2330 	}
2331 }
2332 
2333 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2334 			    struct ktermios *old)
2335 {
2336 	unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2337 	unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2338 	unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2339 	struct sci_port *s = to_sci_port(port);
2340 	const struct plat_sci_reg *reg;
2341 	int min_err = INT_MAX, err;
2342 	unsigned long max_freq = 0;
2343 	int best_clk = -1;
2344 	unsigned long flags;
2345 
2346 	if ((termios->c_cflag & CSIZE) == CS7)
2347 		smr_val |= SCSMR_CHR;
2348 	if (termios->c_cflag & PARENB)
2349 		smr_val |= SCSMR_PE;
2350 	if (termios->c_cflag & PARODD)
2351 		smr_val |= SCSMR_PE | SCSMR_ODD;
2352 	if (termios->c_cflag & CSTOPB)
2353 		smr_val |= SCSMR_STOP;
2354 
2355 	/*
2356 	 * earlyprintk comes here early on with port->uartclk set to zero.
2357 	 * the clock framework is not up and running at this point so here
2358 	 * we assume that 115200 is the maximum baud rate. please note that
2359 	 * the baud rate is not programmed during earlyprintk - it is assumed
2360 	 * that the previous boot loader has enabled required clocks and
2361 	 * setup the baud rate generator hardware for us already.
2362 	 */
2363 	if (!port->uartclk) {
2364 		baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2365 		goto done;
2366 	}
2367 
2368 	for (i = 0; i < SCI_NUM_CLKS; i++)
2369 		max_freq = max(max_freq, s->clk_rates[i]);
2370 
2371 	baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2372 	if (!baud)
2373 		goto done;
2374 
2375 	/*
2376 	 * There can be multiple sources for the sampling clock.  Find the one
2377 	 * that gives us the smallest deviation from the desired baud rate.
2378 	 */
2379 
2380 	/* Optional Undivided External Clock */
2381 	if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2382 	    port->type != PORT_SCIFB) {
2383 		err = sci_sck_calc(s, baud, &srr1);
2384 		if (abs(err) < abs(min_err)) {
2385 			best_clk = SCI_SCK;
2386 			scr_val = SCSCR_CKE1;
2387 			sccks = SCCKS_CKS;
2388 			min_err = err;
2389 			srr = srr1;
2390 			if (!err)
2391 				goto done;
2392 		}
2393 	}
2394 
2395 	/* Optional BRG Frequency Divided External Clock */
2396 	if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2397 		err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2398 				   &srr1);
2399 		if (abs(err) < abs(min_err)) {
2400 			best_clk = SCI_SCIF_CLK;
2401 			scr_val = SCSCR_CKE1;
2402 			sccks = 0;
2403 			min_err = err;
2404 			dl = dl1;
2405 			srr = srr1;
2406 			if (!err)
2407 				goto done;
2408 		}
2409 	}
2410 
2411 	/* Optional BRG Frequency Divided Internal Clock */
2412 	if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2413 		err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2414 				   &srr1);
2415 		if (abs(err) < abs(min_err)) {
2416 			best_clk = SCI_BRG_INT;
2417 			scr_val = SCSCR_CKE1;
2418 			sccks = SCCKS_XIN;
2419 			min_err = err;
2420 			dl = dl1;
2421 			srr = srr1;
2422 			if (!min_err)
2423 				goto done;
2424 		}
2425 	}
2426 
2427 	/* Divided Functional Clock using standard Bit Rate Register */
2428 	err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2429 	if (abs(err) < abs(min_err)) {
2430 		best_clk = SCI_FCK;
2431 		scr_val = 0;
2432 		min_err = err;
2433 		brr = brr1;
2434 		srr = srr1;
2435 		cks = cks1;
2436 	}
2437 
2438 done:
2439 	if (best_clk >= 0)
2440 		dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2441 			s->clks[best_clk], baud, min_err);
2442 
2443 	sci_port_enable(s);
2444 
2445 	/*
2446 	 * Program the optional External Baud Rate Generator (BRG) first.
2447 	 * It controls the mux to select (H)SCK or frequency divided clock.
2448 	 */
2449 	if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2450 		serial_port_out(port, SCDL, dl);
2451 		serial_port_out(port, SCCKS, sccks);
2452 	}
2453 
2454 	spin_lock_irqsave(&port->lock, flags);
2455 
2456 	sci_reset(port);
2457 
2458 	uart_update_timeout(port, termios->c_cflag, baud);
2459 
2460 	/* byte size and parity */
2461 	switch (termios->c_cflag & CSIZE) {
2462 	case CS5:
2463 		bits = 7;
2464 		break;
2465 	case CS6:
2466 		bits = 8;
2467 		break;
2468 	case CS7:
2469 		bits = 9;
2470 		break;
2471 	default:
2472 		bits = 10;
2473 		break;
2474 	}
2475 
2476 	if (termios->c_cflag & CSTOPB)
2477 		bits++;
2478 	if (termios->c_cflag & PARENB)
2479 		bits++;
2480 
2481 	if (best_clk >= 0) {
2482 		if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2483 			switch (srr + 1) {
2484 			case 5:  smr_val |= SCSMR_SRC_5;  break;
2485 			case 7:  smr_val |= SCSMR_SRC_7;  break;
2486 			case 11: smr_val |= SCSMR_SRC_11; break;
2487 			case 13: smr_val |= SCSMR_SRC_13; break;
2488 			case 16: smr_val |= SCSMR_SRC_16; break;
2489 			case 17: smr_val |= SCSMR_SRC_17; break;
2490 			case 19: smr_val |= SCSMR_SRC_19; break;
2491 			case 27: smr_val |= SCSMR_SRC_27; break;
2492 			}
2493 		smr_val |= cks;
2494 		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2495 		serial_port_out(port, SCSMR, smr_val);
2496 		serial_port_out(port, SCBRR, brr);
2497 		if (sci_getreg(port, HSSRR)->size) {
2498 			unsigned int hssrr = srr | HSCIF_SRE;
2499 			/* Calculate deviation from intended rate at the
2500 			 * center of the last stop bit in sampling clocks.
2501 			 */
2502 			int last_stop = bits * 2 - 1;
2503 			int deviation = min_err * srr * last_stop / 2 / baud;
2504 
2505 			if (abs(deviation) >= 2) {
2506 				/* At least two sampling clocks off at the
2507 				 * last stop bit; we can increase the error
2508 				 * margin by shifting the sampling point.
2509 				 */
2510 				int shift = min(-8, max(7, deviation / 2));
2511 
2512 				hssrr |= (shift << HSCIF_SRHP_SHIFT) &
2513 					 HSCIF_SRHP_MASK;
2514 				hssrr |= HSCIF_SRDE;
2515 			}
2516 			serial_port_out(port, HSSRR, hssrr);
2517 		}
2518 
2519 		/* Wait one bit interval */
2520 		udelay((1000000 + (baud - 1)) / baud);
2521 	} else {
2522 		/* Don't touch the bit rate configuration */
2523 		scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2524 		smr_val |= serial_port_in(port, SCSMR) &
2525 			   (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2526 		serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2527 		serial_port_out(port, SCSMR, smr_val);
2528 	}
2529 
2530 	sci_init_pins(port, termios->c_cflag);
2531 
2532 	port->status &= ~UPSTAT_AUTOCTS;
2533 	s->autorts = false;
2534 	reg = sci_getreg(port, SCFCR);
2535 	if (reg->size) {
2536 		unsigned short ctrl = serial_port_in(port, SCFCR);
2537 
2538 		if ((port->flags & UPF_HARD_FLOW) &&
2539 		    (termios->c_cflag & CRTSCTS)) {
2540 			/* There is no CTS interrupt to restart the hardware */
2541 			port->status |= UPSTAT_AUTOCTS;
2542 			/* MCE is enabled when RTS is raised */
2543 			s->autorts = true;
2544 		}
2545 
2546 		/*
2547 		 * As we've done a sci_reset() above, ensure we don't
2548 		 * interfere with the FIFOs while toggling MCE. As the
2549 		 * reset values could still be set, simply mask them out.
2550 		 */
2551 		ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2552 
2553 		serial_port_out(port, SCFCR, ctrl);
2554 	}
2555 	if (port->flags & UPF_HARD_FLOW) {
2556 		/* Refresh (Auto) RTS */
2557 		sci_set_mctrl(port, port->mctrl);
2558 	}
2559 
2560 	scr_val |= SCSCR_RE | SCSCR_TE |
2561 		   (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2562 	serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2563 	if ((srr + 1 == 5) &&
2564 	    (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2565 		/*
2566 		 * In asynchronous mode, when the sampling rate is 1/5, first
2567 		 * received data may become invalid on some SCIFA and SCIFB.
2568 		 * To avoid this problem wait more than 1 serial data time (1
2569 		 * bit time x serial data number) after setting SCSCR.RE = 1.
2570 		 */
2571 		udelay(DIV_ROUND_UP(10 * 1000000, baud));
2572 	}
2573 
2574 	/*
2575 	 * Calculate delay for 2 DMA buffers (4 FIFO).
2576 	 * See serial_core.c::uart_update_timeout().
2577 	 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2578 	 * function calculates 1 jiffie for the data plus 5 jiffies for the
2579 	 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2580 	 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2581 	 * value obtained by this formula is too small. Therefore, if the value
2582 	 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2583 	 */
2584 	s->rx_frame = (10000 * bits) / (baud / 100);
2585 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2586 	s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2587 	if (s->rx_timeout < 20)
2588 		s->rx_timeout = 20;
2589 #endif
2590 
2591 	if ((termios->c_cflag & CREAD) != 0)
2592 		sci_start_rx(port);
2593 
2594 	spin_unlock_irqrestore(&port->lock, flags);
2595 
2596 	sci_port_disable(s);
2597 
2598 	if (UART_ENABLE_MS(port, termios->c_cflag))
2599 		sci_enable_ms(port);
2600 }
2601 
2602 static void sci_pm(struct uart_port *port, unsigned int state,
2603 		   unsigned int oldstate)
2604 {
2605 	struct sci_port *sci_port = to_sci_port(port);
2606 
2607 	switch (state) {
2608 	case UART_PM_STATE_OFF:
2609 		sci_port_disable(sci_port);
2610 		break;
2611 	default:
2612 		sci_port_enable(sci_port);
2613 		break;
2614 	}
2615 }
2616 
2617 static const char *sci_type(struct uart_port *port)
2618 {
2619 	switch (port->type) {
2620 	case PORT_IRDA:
2621 		return "irda";
2622 	case PORT_SCI:
2623 		return "sci";
2624 	case PORT_SCIF:
2625 		return "scif";
2626 	case PORT_SCIFA:
2627 		return "scifa";
2628 	case PORT_SCIFB:
2629 		return "scifb";
2630 	case PORT_HSCIF:
2631 		return "hscif";
2632 	}
2633 
2634 	return NULL;
2635 }
2636 
2637 static int sci_remap_port(struct uart_port *port)
2638 {
2639 	struct sci_port *sport = to_sci_port(port);
2640 
2641 	/*
2642 	 * Nothing to do if there's already an established membase.
2643 	 */
2644 	if (port->membase)
2645 		return 0;
2646 
2647 	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2648 		port->membase = ioremap_nocache(port->mapbase, sport->reg_size);
2649 		if (unlikely(!port->membase)) {
2650 			dev_err(port->dev, "can't remap port#%d\n", port->line);
2651 			return -ENXIO;
2652 		}
2653 	} else {
2654 		/*
2655 		 * For the simple (and majority of) cases where we don't
2656 		 * need to do any remapping, just cast the cookie
2657 		 * directly.
2658 		 */
2659 		port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2660 	}
2661 
2662 	return 0;
2663 }
2664 
2665 static void sci_release_port(struct uart_port *port)
2666 {
2667 	struct sci_port *sport = to_sci_port(port);
2668 
2669 	if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2670 		iounmap(port->membase);
2671 		port->membase = NULL;
2672 	}
2673 
2674 	release_mem_region(port->mapbase, sport->reg_size);
2675 }
2676 
2677 static int sci_request_port(struct uart_port *port)
2678 {
2679 	struct resource *res;
2680 	struct sci_port *sport = to_sci_port(port);
2681 	int ret;
2682 
2683 	res = request_mem_region(port->mapbase, sport->reg_size,
2684 				 dev_name(port->dev));
2685 	if (unlikely(res == NULL)) {
2686 		dev_err(port->dev, "request_mem_region failed.");
2687 		return -EBUSY;
2688 	}
2689 
2690 	ret = sci_remap_port(port);
2691 	if (unlikely(ret != 0)) {
2692 		release_resource(res);
2693 		return ret;
2694 	}
2695 
2696 	return 0;
2697 }
2698 
2699 static void sci_config_port(struct uart_port *port, int flags)
2700 {
2701 	if (flags & UART_CONFIG_TYPE) {
2702 		struct sci_port *sport = to_sci_port(port);
2703 
2704 		port->type = sport->cfg->type;
2705 		sci_request_port(port);
2706 	}
2707 }
2708 
2709 static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2710 {
2711 	if (ser->baud_base < 2400)
2712 		/* No paper tape reader for Mitch.. */
2713 		return -EINVAL;
2714 
2715 	return 0;
2716 }
2717 
2718 static const struct uart_ops sci_uart_ops = {
2719 	.tx_empty	= sci_tx_empty,
2720 	.set_mctrl	= sci_set_mctrl,
2721 	.get_mctrl	= sci_get_mctrl,
2722 	.start_tx	= sci_start_tx,
2723 	.stop_tx	= sci_stop_tx,
2724 	.stop_rx	= sci_stop_rx,
2725 	.enable_ms	= sci_enable_ms,
2726 	.break_ctl	= sci_break_ctl,
2727 	.startup	= sci_startup,
2728 	.shutdown	= sci_shutdown,
2729 	.flush_buffer	= sci_flush_buffer,
2730 	.set_termios	= sci_set_termios,
2731 	.pm		= sci_pm,
2732 	.type		= sci_type,
2733 	.release_port	= sci_release_port,
2734 	.request_port	= sci_request_port,
2735 	.config_port	= sci_config_port,
2736 	.verify_port	= sci_verify_port,
2737 #ifdef CONFIG_CONSOLE_POLL
2738 	.poll_get_char	= sci_poll_get_char,
2739 	.poll_put_char	= sci_poll_put_char,
2740 #endif
2741 };
2742 
2743 static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2744 {
2745 	const char *clk_names[] = {
2746 		[SCI_FCK] = "fck",
2747 		[SCI_SCK] = "sck",
2748 		[SCI_BRG_INT] = "brg_int",
2749 		[SCI_SCIF_CLK] = "scif_clk",
2750 	};
2751 	struct clk *clk;
2752 	unsigned int i;
2753 
2754 	if (sci_port->cfg->type == PORT_HSCIF)
2755 		clk_names[SCI_SCK] = "hsck";
2756 
2757 	for (i = 0; i < SCI_NUM_CLKS; i++) {
2758 		clk = devm_clk_get(dev, clk_names[i]);
2759 		if (PTR_ERR(clk) == -EPROBE_DEFER)
2760 			return -EPROBE_DEFER;
2761 
2762 		if (IS_ERR(clk) && i == SCI_FCK) {
2763 			/*
2764 			 * "fck" used to be called "sci_ick", and we need to
2765 			 * maintain DT backward compatibility.
2766 			 */
2767 			clk = devm_clk_get(dev, "sci_ick");
2768 			if (PTR_ERR(clk) == -EPROBE_DEFER)
2769 				return -EPROBE_DEFER;
2770 
2771 			if (!IS_ERR(clk))
2772 				goto found;
2773 
2774 			/*
2775 			 * Not all SH platforms declare a clock lookup entry
2776 			 * for SCI devices, in which case we need to get the
2777 			 * global "peripheral_clk" clock.
2778 			 */
2779 			clk = devm_clk_get(dev, "peripheral_clk");
2780 			if (!IS_ERR(clk))
2781 				goto found;
2782 
2783 			dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2784 				PTR_ERR(clk));
2785 			return PTR_ERR(clk);
2786 		}
2787 
2788 found:
2789 		if (IS_ERR(clk))
2790 			dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2791 				PTR_ERR(clk));
2792 		else
2793 			dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
2794 				clk, clk_get_rate(clk));
2795 		sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2796 	}
2797 	return 0;
2798 }
2799 
2800 static const struct sci_port_params *
2801 sci_probe_regmap(const struct plat_sci_port *cfg)
2802 {
2803 	unsigned int regtype;
2804 
2805 	if (cfg->regtype != SCIx_PROBE_REGTYPE)
2806 		return &sci_port_params[cfg->regtype];
2807 
2808 	switch (cfg->type) {
2809 	case PORT_SCI:
2810 		regtype = SCIx_SCI_REGTYPE;
2811 		break;
2812 	case PORT_IRDA:
2813 		regtype = SCIx_IRDA_REGTYPE;
2814 		break;
2815 	case PORT_SCIFA:
2816 		regtype = SCIx_SCIFA_REGTYPE;
2817 		break;
2818 	case PORT_SCIFB:
2819 		regtype = SCIx_SCIFB_REGTYPE;
2820 		break;
2821 	case PORT_SCIF:
2822 		/*
2823 		 * The SH-4 is a bit of a misnomer here, although that's
2824 		 * where this particular port layout originated. This
2825 		 * configuration (or some slight variation thereof)
2826 		 * remains the dominant model for all SCIFs.
2827 		 */
2828 		regtype = SCIx_SH4_SCIF_REGTYPE;
2829 		break;
2830 	case PORT_HSCIF:
2831 		regtype = SCIx_HSCIF_REGTYPE;
2832 		break;
2833 	default:
2834 		pr_err("Can't probe register map for given port\n");
2835 		return NULL;
2836 	}
2837 
2838 	return &sci_port_params[regtype];
2839 }
2840 
2841 static int sci_init_single(struct platform_device *dev,
2842 			   struct sci_port *sci_port, unsigned int index,
2843 			   const struct plat_sci_port *p, bool early)
2844 {
2845 	struct uart_port *port = &sci_port->port;
2846 	const struct resource *res;
2847 	unsigned int i;
2848 	int ret;
2849 
2850 	sci_port->cfg	= p;
2851 
2852 	port->ops	= &sci_uart_ops;
2853 	port->iotype	= UPIO_MEM;
2854 	port->line	= index;
2855 
2856 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2857 	if (res == NULL)
2858 		return -ENOMEM;
2859 
2860 	port->mapbase = res->start;
2861 	sci_port->reg_size = resource_size(res);
2862 
2863 	for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i)
2864 		sci_port->irqs[i] = platform_get_irq(dev, i);
2865 
2866 	/* The SCI generates several interrupts. They can be muxed together or
2867 	 * connected to different interrupt lines. In the muxed case only one
2868 	 * interrupt resource is specified as there is only one interrupt ID.
2869 	 * In the non-muxed case, up to 6 interrupt signals might be generated
2870 	 * from the SCI, however those signals might have their own individual
2871 	 * interrupt ID numbers, or muxed together with another interrupt.
2872 	 */
2873 	if (sci_port->irqs[0] < 0)
2874 		return -ENXIO;
2875 
2876 	if (sci_port->irqs[1] < 0)
2877 		for (i = 1; i < ARRAY_SIZE(sci_port->irqs); i++)
2878 			sci_port->irqs[i] = sci_port->irqs[0];
2879 
2880 	sci_port->params = sci_probe_regmap(p);
2881 	if (unlikely(sci_port->params == NULL))
2882 		return -EINVAL;
2883 
2884 	switch (p->type) {
2885 	case PORT_SCIFB:
2886 		sci_port->rx_trigger = 48;
2887 		break;
2888 	case PORT_HSCIF:
2889 		sci_port->rx_trigger = 64;
2890 		break;
2891 	case PORT_SCIFA:
2892 		sci_port->rx_trigger = 32;
2893 		break;
2894 	case PORT_SCIF:
2895 		if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2896 			/* RX triggering not implemented for this IP */
2897 			sci_port->rx_trigger = 1;
2898 		else
2899 			sci_port->rx_trigger = 8;
2900 		break;
2901 	default:
2902 		sci_port->rx_trigger = 1;
2903 		break;
2904 	}
2905 
2906 	sci_port->rx_fifo_timeout = 0;
2907 	sci_port->hscif_tot = 0;
2908 
2909 	/* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2910 	 * match the SoC datasheet, this should be investigated. Let platform
2911 	 * data override the sampling rate for now.
2912 	 */
2913 	sci_port->sampling_rate_mask = p->sampling_rate
2914 				     ? SCI_SR(p->sampling_rate)
2915 				     : sci_port->params->sampling_rate_mask;
2916 
2917 	if (!early) {
2918 		ret = sci_init_clocks(sci_port, &dev->dev);
2919 		if (ret < 0)
2920 			return ret;
2921 
2922 		port->dev = &dev->dev;
2923 
2924 		pm_runtime_enable(&dev->dev);
2925 	}
2926 
2927 	port->type		= p->type;
2928 	port->flags		= UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2929 	port->fifosize		= sci_port->params->fifosize;
2930 
2931 	if (port->type == PORT_SCI) {
2932 		if (sci_port->reg_size >= 0x20)
2933 			port->regshift = 2;
2934 		else
2935 			port->regshift = 1;
2936 	}
2937 
2938 	/*
2939 	 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2940 	 * for the multi-IRQ ports, which is where we are primarily
2941 	 * concerned with the shutdown path synchronization.
2942 	 *
2943 	 * For the muxed case there's nothing more to do.
2944 	 */
2945 	port->irq		= sci_port->irqs[SCIx_RXI_IRQ];
2946 	port->irqflags		= 0;
2947 
2948 	port->serial_in		= sci_serial_in;
2949 	port->serial_out	= sci_serial_out;
2950 
2951 	return 0;
2952 }
2953 
2954 static void sci_cleanup_single(struct sci_port *port)
2955 {
2956 	pm_runtime_disable(port->port.dev);
2957 }
2958 
2959 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2960     defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2961 static void serial_console_putchar(struct uart_port *port, int ch)
2962 {
2963 	sci_poll_put_char(port, ch);
2964 }
2965 
2966 /*
2967  *	Print a string to the serial port trying not to disturb
2968  *	any possible real use of the port...
2969  */
2970 static void serial_console_write(struct console *co, const char *s,
2971 				 unsigned count)
2972 {
2973 	struct sci_port *sci_port = &sci_ports[co->index];
2974 	struct uart_port *port = &sci_port->port;
2975 	unsigned short bits, ctrl, ctrl_temp;
2976 	unsigned long flags;
2977 	int locked = 1;
2978 
2979 #if defined(SUPPORT_SYSRQ)
2980 	if (port->sysrq)
2981 		locked = 0;
2982 	else
2983 #endif
2984 	if (oops_in_progress)
2985 		locked = spin_trylock_irqsave(&port->lock, flags);
2986 	else
2987 		spin_lock_irqsave(&port->lock, flags);
2988 
2989 	/* first save SCSCR then disable interrupts, keep clock source */
2990 	ctrl = serial_port_in(port, SCSCR);
2991 	ctrl_temp = SCSCR_RE | SCSCR_TE |
2992 		    (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
2993 		    (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
2994 	serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
2995 
2996 	uart_console_write(port, s, count, serial_console_putchar);
2997 
2998 	/* wait until fifo is empty and last bit has been transmitted */
2999 	bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
3000 	while ((serial_port_in(port, SCxSR) & bits) != bits)
3001 		cpu_relax();
3002 
3003 	/* restore the SCSCR */
3004 	serial_port_out(port, SCSCR, ctrl);
3005 
3006 	if (locked)
3007 		spin_unlock_irqrestore(&port->lock, flags);
3008 }
3009 
3010 static int serial_console_setup(struct console *co, char *options)
3011 {
3012 	struct sci_port *sci_port;
3013 	struct uart_port *port;
3014 	int baud = 115200;
3015 	int bits = 8;
3016 	int parity = 'n';
3017 	int flow = 'n';
3018 	int ret;
3019 
3020 	/*
3021 	 * Refuse to handle any bogus ports.
3022 	 */
3023 	if (co->index < 0 || co->index >= SCI_NPORTS)
3024 		return -ENODEV;
3025 
3026 	sci_port = &sci_ports[co->index];
3027 	port = &sci_port->port;
3028 
3029 	/*
3030 	 * Refuse to handle uninitialized ports.
3031 	 */
3032 	if (!port->ops)
3033 		return -ENODEV;
3034 
3035 	ret = sci_remap_port(port);
3036 	if (unlikely(ret != 0))
3037 		return ret;
3038 
3039 	if (options)
3040 		uart_parse_options(options, &baud, &parity, &bits, &flow);
3041 
3042 	return uart_set_options(port, co, baud, parity, bits, flow);
3043 }
3044 
3045 static struct console serial_console = {
3046 	.name		= "ttySC",
3047 	.device		= uart_console_device,
3048 	.write		= serial_console_write,
3049 	.setup		= serial_console_setup,
3050 	.flags		= CON_PRINTBUFFER,
3051 	.index		= -1,
3052 	.data		= &sci_uart_driver,
3053 };
3054 
3055 static struct console early_serial_console = {
3056 	.name           = "early_ttySC",
3057 	.write          = serial_console_write,
3058 	.flags          = CON_PRINTBUFFER,
3059 	.index		= -1,
3060 };
3061 
3062 static char early_serial_buf[32];
3063 
3064 static int sci_probe_earlyprintk(struct platform_device *pdev)
3065 {
3066 	const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
3067 
3068 	if (early_serial_console.data)
3069 		return -EEXIST;
3070 
3071 	early_serial_console.index = pdev->id;
3072 
3073 	sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
3074 
3075 	serial_console_setup(&early_serial_console, early_serial_buf);
3076 
3077 	if (!strstr(early_serial_buf, "keep"))
3078 		early_serial_console.flags |= CON_BOOT;
3079 
3080 	register_console(&early_serial_console);
3081 	return 0;
3082 }
3083 
3084 #define SCI_CONSOLE	(&serial_console)
3085 
3086 #else
3087 static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3088 {
3089 	return -EINVAL;
3090 }
3091 
3092 #define SCI_CONSOLE	NULL
3093 
3094 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3095 
3096 static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3097 
3098 static DEFINE_MUTEX(sci_uart_registration_lock);
3099 static struct uart_driver sci_uart_driver = {
3100 	.owner		= THIS_MODULE,
3101 	.driver_name	= "sci",
3102 	.dev_name	= "ttySC",
3103 	.major		= SCI_MAJOR,
3104 	.minor		= SCI_MINOR_START,
3105 	.nr		= SCI_NPORTS,
3106 	.cons		= SCI_CONSOLE,
3107 };
3108 
3109 static int sci_remove(struct platform_device *dev)
3110 {
3111 	struct sci_port *port = platform_get_drvdata(dev);
3112 	unsigned int type = port->port.type;	/* uart_remove_... clears it */
3113 
3114 	sci_ports_in_use &= ~BIT(port->port.line);
3115 	uart_remove_one_port(&sci_uart_driver, &port->port);
3116 
3117 	sci_cleanup_single(port);
3118 
3119 	if (port->port.fifosize > 1) {
3120 		sysfs_remove_file(&dev->dev.kobj,
3121 				  &dev_attr_rx_fifo_trigger.attr);
3122 	}
3123 	if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF) {
3124 		sysfs_remove_file(&dev->dev.kobj,
3125 				  &dev_attr_rx_fifo_timeout.attr);
3126 	}
3127 
3128 	return 0;
3129 }
3130 
3131 
3132 #define SCI_OF_DATA(type, regtype)	(void *)((type) << 16 | (regtype))
3133 #define SCI_OF_TYPE(data)		((unsigned long)(data) >> 16)
3134 #define SCI_OF_REGTYPE(data)		((unsigned long)(data) & 0xffff)
3135 
3136 static const struct of_device_id of_sci_match[] = {
3137 	/* SoC-specific types */
3138 	{
3139 		.compatible = "renesas,scif-r7s72100",
3140 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3141 	},
3142 	{
3143 		.compatible = "renesas,scif-r7s9210",
3144 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3145 	},
3146 	/* Family-specific types */
3147 	{
3148 		.compatible = "renesas,rcar-gen1-scif",
3149 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3150 	}, {
3151 		.compatible = "renesas,rcar-gen2-scif",
3152 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3153 	}, {
3154 		.compatible = "renesas,rcar-gen3-scif",
3155 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3156 	},
3157 	/* Generic types */
3158 	{
3159 		.compatible = "renesas,scif",
3160 		.data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3161 	}, {
3162 		.compatible = "renesas,scifa",
3163 		.data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3164 	}, {
3165 		.compatible = "renesas,scifb",
3166 		.data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3167 	}, {
3168 		.compatible = "renesas,hscif",
3169 		.data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3170 	}, {
3171 		.compatible = "renesas,sci",
3172 		.data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3173 	}, {
3174 		/* Terminator */
3175 	},
3176 };
3177 MODULE_DEVICE_TABLE(of, of_sci_match);
3178 
3179 static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3180 					  unsigned int *dev_id)
3181 {
3182 	struct device_node *np = pdev->dev.of_node;
3183 	struct plat_sci_port *p;
3184 	struct sci_port *sp;
3185 	const void *data;
3186 	int id;
3187 
3188 	if (!IS_ENABLED(CONFIG_OF) || !np)
3189 		return NULL;
3190 
3191 	data = of_device_get_match_data(&pdev->dev);
3192 
3193 	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3194 	if (!p)
3195 		return NULL;
3196 
3197 	/* Get the line number from the aliases node. */
3198 	id = of_alias_get_id(np, "serial");
3199 	if (id < 0 && ~sci_ports_in_use)
3200 		id = ffz(sci_ports_in_use);
3201 	if (id < 0) {
3202 		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3203 		return NULL;
3204 	}
3205 	if (id >= ARRAY_SIZE(sci_ports)) {
3206 		dev_err(&pdev->dev, "serial%d out of range\n", id);
3207 		return NULL;
3208 	}
3209 
3210 	sp = &sci_ports[id];
3211 	*dev_id = id;
3212 
3213 	p->type = SCI_OF_TYPE(data);
3214 	p->regtype = SCI_OF_REGTYPE(data);
3215 
3216 	sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3217 
3218 	return p;
3219 }
3220 
3221 static int sci_probe_single(struct platform_device *dev,
3222 				      unsigned int index,
3223 				      struct plat_sci_port *p,
3224 				      struct sci_port *sciport)
3225 {
3226 	int ret;
3227 
3228 	/* Sanity check */
3229 	if (unlikely(index >= SCI_NPORTS)) {
3230 		dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3231 			   index+1, SCI_NPORTS);
3232 		dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3233 		return -EINVAL;
3234 	}
3235 	BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
3236 	if (sci_ports_in_use & BIT(index))
3237 		return -EBUSY;
3238 
3239 	mutex_lock(&sci_uart_registration_lock);
3240 	if (!sci_uart_driver.state) {
3241 		ret = uart_register_driver(&sci_uart_driver);
3242 		if (ret) {
3243 			mutex_unlock(&sci_uart_registration_lock);
3244 			return ret;
3245 		}
3246 	}
3247 	mutex_unlock(&sci_uart_registration_lock);
3248 
3249 	ret = sci_init_single(dev, sciport, index, p, false);
3250 	if (ret)
3251 		return ret;
3252 
3253 	sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3254 	if (IS_ERR(sciport->gpios) && PTR_ERR(sciport->gpios) != -ENOSYS)
3255 		return PTR_ERR(sciport->gpios);
3256 
3257 	if (sciport->has_rtscts) {
3258 		if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3259 							UART_GPIO_CTS)) ||
3260 		    !IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3261 							UART_GPIO_RTS))) {
3262 			dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3263 			return -EINVAL;
3264 		}
3265 		sciport->port.flags |= UPF_HARD_FLOW;
3266 	}
3267 
3268 	ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3269 	if (ret) {
3270 		sci_cleanup_single(sciport);
3271 		return ret;
3272 	}
3273 
3274 	return 0;
3275 }
3276 
3277 static int sci_probe(struct platform_device *dev)
3278 {
3279 	struct plat_sci_port *p;
3280 	struct sci_port *sp;
3281 	unsigned int dev_id;
3282 	int ret;
3283 
3284 	/*
3285 	 * If we've come here via earlyprintk initialization, head off to
3286 	 * the special early probe. We don't have sufficient device state
3287 	 * to make it beyond this yet.
3288 	 */
3289 	if (is_early_platform_device(dev))
3290 		return sci_probe_earlyprintk(dev);
3291 
3292 	if (dev->dev.of_node) {
3293 		p = sci_parse_dt(dev, &dev_id);
3294 		if (p == NULL)
3295 			return -EINVAL;
3296 	} else {
3297 		p = dev->dev.platform_data;
3298 		if (p == NULL) {
3299 			dev_err(&dev->dev, "no platform data supplied\n");
3300 			return -EINVAL;
3301 		}
3302 
3303 		dev_id = dev->id;
3304 	}
3305 
3306 	sp = &sci_ports[dev_id];
3307 	platform_set_drvdata(dev, sp);
3308 
3309 	ret = sci_probe_single(dev, dev_id, p, sp);
3310 	if (ret)
3311 		return ret;
3312 
3313 	if (sp->port.fifosize > 1) {
3314 		ret = sysfs_create_file(&dev->dev.kobj,
3315 				&dev_attr_rx_fifo_trigger.attr);
3316 		if (ret)
3317 			return ret;
3318 	}
3319 	if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3320 	    sp->port.type == PORT_HSCIF) {
3321 		ret = sysfs_create_file(&dev->dev.kobj,
3322 				&dev_attr_rx_fifo_timeout.attr);
3323 		if (ret) {
3324 			if (sp->port.fifosize > 1) {
3325 				sysfs_remove_file(&dev->dev.kobj,
3326 					&dev_attr_rx_fifo_trigger.attr);
3327 			}
3328 			return ret;
3329 		}
3330 	}
3331 
3332 #ifdef CONFIG_SH_STANDARD_BIOS
3333 	sh_bios_gdb_detach();
3334 #endif
3335 
3336 	sci_ports_in_use |= BIT(dev_id);
3337 	return 0;
3338 }
3339 
3340 static __maybe_unused int sci_suspend(struct device *dev)
3341 {
3342 	struct sci_port *sport = dev_get_drvdata(dev);
3343 
3344 	if (sport)
3345 		uart_suspend_port(&sci_uart_driver, &sport->port);
3346 
3347 	return 0;
3348 }
3349 
3350 static __maybe_unused int sci_resume(struct device *dev)
3351 {
3352 	struct sci_port *sport = dev_get_drvdata(dev);
3353 
3354 	if (sport)
3355 		uart_resume_port(&sci_uart_driver, &sport->port);
3356 
3357 	return 0;
3358 }
3359 
3360 static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3361 
3362 static struct platform_driver sci_driver = {
3363 	.probe		= sci_probe,
3364 	.remove		= sci_remove,
3365 	.driver		= {
3366 		.name	= "sh-sci",
3367 		.pm	= &sci_dev_pm_ops,
3368 		.of_match_table = of_match_ptr(of_sci_match),
3369 	},
3370 };
3371 
3372 static int __init sci_init(void)
3373 {
3374 	pr_info("%s\n", banner);
3375 
3376 	return platform_driver_register(&sci_driver);
3377 }
3378 
3379 static void __exit sci_exit(void)
3380 {
3381 	platform_driver_unregister(&sci_driver);
3382 
3383 	if (sci_uart_driver.state)
3384 		uart_unregister_driver(&sci_uart_driver);
3385 }
3386 
3387 #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
3388 early_platform_init_buffer("earlyprintk", &sci_driver,
3389 			   early_serial_buf, ARRAY_SIZE(early_serial_buf));
3390 #endif
3391 #ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3392 static struct plat_sci_port port_cfg __initdata;
3393 
3394 static int __init early_console_setup(struct earlycon_device *device,
3395 				      int type)
3396 {
3397 	if (!device->port.membase)
3398 		return -ENODEV;
3399 
3400 	device->port.serial_in = sci_serial_in;
3401 	device->port.serial_out	= sci_serial_out;
3402 	device->port.type = type;
3403 	memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3404 	port_cfg.type = type;
3405 	sci_ports[0].cfg = &port_cfg;
3406 	sci_ports[0].params = sci_probe_regmap(&port_cfg);
3407 	port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3408 	sci_serial_out(&sci_ports[0].port, SCSCR,
3409 		       SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3410 
3411 	device->con->write = serial_console_write;
3412 	return 0;
3413 }
3414 static int __init sci_early_console_setup(struct earlycon_device *device,
3415 					  const char *opt)
3416 {
3417 	return early_console_setup(device, PORT_SCI);
3418 }
3419 static int __init scif_early_console_setup(struct earlycon_device *device,
3420 					  const char *opt)
3421 {
3422 	return early_console_setup(device, PORT_SCIF);
3423 }
3424 static int __init rzscifa_early_console_setup(struct earlycon_device *device,
3425 					  const char *opt)
3426 {
3427 	port_cfg.regtype = SCIx_RZ_SCIFA_REGTYPE;
3428 	return early_console_setup(device, PORT_SCIF);
3429 }
3430 static int __init scifa_early_console_setup(struct earlycon_device *device,
3431 					  const char *opt)
3432 {
3433 	return early_console_setup(device, PORT_SCIFA);
3434 }
3435 static int __init scifb_early_console_setup(struct earlycon_device *device,
3436 					  const char *opt)
3437 {
3438 	return early_console_setup(device, PORT_SCIFB);
3439 }
3440 static int __init hscif_early_console_setup(struct earlycon_device *device,
3441 					  const char *opt)
3442 {
3443 	return early_console_setup(device, PORT_HSCIF);
3444 }
3445 
3446 OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3447 OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3448 OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rzscifa_early_console_setup);
3449 OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3450 OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3451 OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3452 #endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3453 
3454 module_init(sci_init);
3455 module_exit(sci_exit);
3456 
3457 MODULE_LICENSE("GPL");
3458 MODULE_ALIAS("platform:sh-sci");
3459 MODULE_AUTHOR("Paul Mundt");
3460 MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
3461