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Merge tag 'block-5.11-2021-01-10' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / tty / serial / sh-sci.c
blobe1179e74a2b89d892f4c8e0edceb3378c6755e5a
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
4 *
5 * Copyright (C) 2002 - 2011 Paul Mundt
6 * Copyright (C) 2015 Glider bvba
7 * Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
8 *
9 * based off of the old drivers/char/sh-sci.c by:
10 *
11 * Copyright (C) 1999, 2000 Niibe Yutaka
12 * Copyright (C) 2000 Sugioka Toshinobu
13 * Modified to support multiple serial ports. Stuart Menefy (May 2000).
14 * Modified to support SecureEdge. David McCullough (2002)
15 * Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
16 * Removed SH7300 support (Jul 2007).
17 */
18 #undef DEBUG
19
20 #include <linux/clk.h>
21 #include <linux/console.h>
22 #include <linux/ctype.h>
23 #include <linux/cpufreq.h>
24 #include <linux/delay.h>
25 #include <linux/dmaengine.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/err.h>
28 #include <linux/errno.h>
29 #include <linux/init.h>
30 #include <linux/interrupt.h>
31 #include <linux/ioport.h>
32 #include <linux/ktime.h>
33 #include <linux/major.h>
34 #include <linux/module.h>
35 #include <linux/mm.h>
36 #include <linux/of.h>
37 #include <linux/of_device.h>
38 #include <linux/platform_device.h>
39 #include <linux/pm_runtime.h>
40 #include <linux/scatterlist.h>
41 #include <linux/serial.h>
42 #include <linux/serial_sci.h>
43 #include <linux/sh_dma.h>
44 #include <linux/slab.h>
45 #include <linux/string.h>
46 #include <linux/sysrq.h>
47 #include <linux/timer.h>
48 #include <linux/tty.h>
49 #include <linux/tty_flip.h>
50
51 #ifdef CONFIG_SUPERH
52 #include <asm/sh_bios.h>
53 #include <asm/platform_early.h>
54 #endif
55
56 #include "serial_mctrl_gpio.h"
57 #include "sh-sci.h"
58
59 /* Offsets into the sci_port->irqs array */
60 enum {
61 SCIx_ERI_IRQ,
62 SCIx_RXI_IRQ,
63 SCIx_TXI_IRQ,
64 SCIx_BRI_IRQ,
65 SCIx_DRI_IRQ,
66 SCIx_TEI_IRQ,
67 SCIx_NR_IRQS,
68
69 SCIx_MUX_IRQ = SCIx_NR_IRQS, /* special case */
70 };
71
72 #define SCIx_IRQ_IS_MUXED(port) \
73 ((port)->irqs[SCIx_ERI_IRQ] == \
74 (port)->irqs[SCIx_RXI_IRQ]) || \
75 ((port)->irqs[SCIx_ERI_IRQ] && \
76 ((port)->irqs[SCIx_RXI_IRQ] < 0))
77
78 enum SCI_CLKS {
79 SCI_FCK, /* Functional Clock */
80 SCI_SCK, /* Optional External Clock */
81 SCI_BRG_INT, /* Optional BRG Internal Clock Source */
82 SCI_SCIF_CLK, /* Optional BRG External Clock Source */
83 SCI_NUM_CLKS
84 };
85
86 /* Bit x set means sampling rate x + 1 is supported */
87 #define SCI_SR(x) BIT((x) - 1)
88 #define SCI_SR_RANGE(x, y) GENMASK((y) - 1, (x) - 1)
89
90 #define SCI_SR_SCIFAB SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
91 SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
92 SCI_SR(19) | SCI_SR(27)
93
94 #define min_sr(_port) ffs((_port)->sampling_rate_mask)
95 #define max_sr(_port) fls((_port)->sampling_rate_mask)
96
97 /* Iterate over all supported sampling rates, from high to low */
98 #define for_each_sr(_sr, _port) \
99 for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--) \
100 if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
101
102 struct plat_sci_reg {
103 u8 offset, size;
104 };
105
106 struct sci_port_params {
107 const struct plat_sci_reg regs[SCIx_NR_REGS];
108 unsigned int fifosize;
109 unsigned int overrun_reg;
110 unsigned int overrun_mask;
111 unsigned int sampling_rate_mask;
112 unsigned int error_mask;
113 unsigned int error_clear;
114 };
115
116 struct sci_port {
117 struct uart_port port;
118
119 /* Platform configuration */
120 const struct sci_port_params *params;
121 const struct plat_sci_port *cfg;
122 unsigned int sampling_rate_mask;
123 resource_size_t reg_size;
124 struct mctrl_gpios *gpios;
125
126 /* Clocks */
127 struct clk *clks[SCI_NUM_CLKS];
128 unsigned long clk_rates[SCI_NUM_CLKS];
129
130 int irqs[SCIx_NR_IRQS];
131 char *irqstr[SCIx_NR_IRQS];
132
133 struct dma_chan *chan_tx;
134 struct dma_chan *chan_rx;
135
136 #ifdef CONFIG_SERIAL_SH_SCI_DMA
137 struct dma_chan *chan_tx_saved;
138 struct dma_chan *chan_rx_saved;
139 dma_cookie_t cookie_tx;
140 dma_cookie_t cookie_rx[2];
141 dma_cookie_t active_rx;
142 dma_addr_t tx_dma_addr;
143 unsigned int tx_dma_len;
144 struct scatterlist sg_rx[2];
145 void *rx_buf[2];
146 size_t buf_len_rx;
147 struct work_struct work_tx;
148 struct hrtimer rx_timer;
149 unsigned int rx_timeout; /* microseconds */
150 #endif
151 unsigned int rx_frame;
152 int rx_trigger;
153 struct timer_list rx_fifo_timer;
154 int rx_fifo_timeout;
155 u16 hscif_tot;
156
157 bool has_rtscts;
158 bool autorts;
159 };
160
161 #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
162
163 static struct sci_port sci_ports[SCI_NPORTS];
164 static unsigned long sci_ports_in_use;
165 static struct uart_driver sci_uart_driver;
166
167 static inline struct sci_port *
168 to_sci_port(struct uart_port *uart)
169 {
170 return container_of(uart, struct sci_port, port);
171 }
172
173 static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
174 /*
175 * Common SCI definitions, dependent on the port's regshift
176 * value.
177 */
178 [SCIx_SCI_REGTYPE] = {
179 .regs = {
180 [SCSMR] = { 0x00, 8 },
181 [SCBRR] = { 0x01, 8 },
182 [SCSCR] = { 0x02, 8 },
183 [SCxTDR] = { 0x03, 8 },
184 [SCxSR] = { 0x04, 8 },
185 [SCxRDR] = { 0x05, 8 },
186 },
187 .fifosize = 1,
188 .overrun_reg = SCxSR,
189 .overrun_mask = SCI_ORER,
190 .sampling_rate_mask = SCI_SR(32),
191 .error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
192 .error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
193 },
194
195 /*
196 * Common definitions for legacy IrDA ports.
197 */
198 [SCIx_IRDA_REGTYPE] = {
199 .regs = {
200 [SCSMR] = { 0x00, 8 },
201 [SCBRR] = { 0x02, 8 },
202 [SCSCR] = { 0x04, 8 },
203 [SCxTDR] = { 0x06, 8 },
204 [SCxSR] = { 0x08, 16 },
205 [SCxRDR] = { 0x0a, 8 },
206 [SCFCR] = { 0x0c, 8 },
207 [SCFDR] = { 0x0e, 16 },
208 },
209 .fifosize = 1,
210 .overrun_reg = SCxSR,
211 .overrun_mask = SCI_ORER,
212 .sampling_rate_mask = SCI_SR(32),
213 .error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
214 .error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
215 },
216
217 /*
218 * Common SCIFA definitions.
219 */
220 [SCIx_SCIFA_REGTYPE] = {
221 .regs = {
222 [SCSMR] = { 0x00, 16 },
223 [SCBRR] = { 0x04, 8 },
224 [SCSCR] = { 0x08, 16 },
225 [SCxTDR] = { 0x20, 8 },
226 [SCxSR] = { 0x14, 16 },
227 [SCxRDR] = { 0x24, 8 },
228 [SCFCR] = { 0x18, 16 },
229 [SCFDR] = { 0x1c, 16 },
230 [SCPCR] = { 0x30, 16 },
231 [SCPDR] = { 0x34, 16 },
232 },
233 .fifosize = 64,
234 .overrun_reg = SCxSR,
235 .overrun_mask = SCIFA_ORER,
236 .sampling_rate_mask = SCI_SR_SCIFAB,
237 .error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
238 .error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
239 },
240
241 /*
242 * Common SCIFB definitions.
243 */
244 [SCIx_SCIFB_REGTYPE] = {
245 .regs = {
246 [SCSMR] = { 0x00, 16 },
247 [SCBRR] = { 0x04, 8 },
248 [SCSCR] = { 0x08, 16 },
249 [SCxTDR] = { 0x40, 8 },
250 [SCxSR] = { 0x14, 16 },
251 [SCxRDR] = { 0x60, 8 },
252 [SCFCR] = { 0x18, 16 },
253 [SCTFDR] = { 0x38, 16 },
254 [SCRFDR] = { 0x3c, 16 },
255 [SCPCR] = { 0x30, 16 },
256 [SCPDR] = { 0x34, 16 },
257 },
258 .fifosize = 256,
259 .overrun_reg = SCxSR,
260 .overrun_mask = SCIFA_ORER,
261 .sampling_rate_mask = SCI_SR_SCIFAB,
262 .error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
263 .error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
264 },
265
266 /*
267 * Common SH-2(A) SCIF definitions for ports with FIFO data
268 * count registers.
269 */
270 [SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
271 .regs = {
272 [SCSMR] = { 0x00, 16 },
273 [SCBRR] = { 0x04, 8 },
274 [SCSCR] = { 0x08, 16 },
275 [SCxTDR] = { 0x0c, 8 },
276 [SCxSR] = { 0x10, 16 },
277 [SCxRDR] = { 0x14, 8 },
278 [SCFCR] = { 0x18, 16 },
279 [SCFDR] = { 0x1c, 16 },
280 [SCSPTR] = { 0x20, 16 },
281 [SCLSR] = { 0x24, 16 },
282 },
283 .fifosize = 16,
284 .overrun_reg = SCLSR,
285 .overrun_mask = SCLSR_ORER,
286 .sampling_rate_mask = SCI_SR(32),
287 .error_mask = SCIF_DEFAULT_ERROR_MASK,
288 .error_clear = SCIF_ERROR_CLEAR,
289 },
290
291 /*
292 * The "SCIFA" that is in RZ/T and RZ/A2.
293 * It looks like a normal SCIF with FIFO data, but with a
294 * compressed address space. Also, the break out of interrupts
295 * are different: ERI/BRI, RXI, TXI, TEI, DRI.
296 */
297 [SCIx_RZ_SCIFA_REGTYPE] = {
298 .regs = {
299 [SCSMR] = { 0x00, 16 },
300 [SCBRR] = { 0x02, 8 },
301 [SCSCR] = { 0x04, 16 },
302 [SCxTDR] = { 0x06, 8 },
303 [SCxSR] = { 0x08, 16 },
304 [SCxRDR] = { 0x0A, 8 },
305 [SCFCR] = { 0x0C, 16 },
306 [SCFDR] = { 0x0E, 16 },
307 [SCSPTR] = { 0x10, 16 },
308 [SCLSR] = { 0x12, 16 },
309 },
310 .fifosize = 16,
311 .overrun_reg = SCLSR,
312 .overrun_mask = SCLSR_ORER,
313 .sampling_rate_mask = SCI_SR(32),
314 .error_mask = SCIF_DEFAULT_ERROR_MASK,
315 .error_clear = SCIF_ERROR_CLEAR,
316 },
317
318 /*
319 * Common SH-3 SCIF definitions.
320 */
321 [SCIx_SH3_SCIF_REGTYPE] = {
322 .regs = {
323 [SCSMR] = { 0x00, 8 },
324 [SCBRR] = { 0x02, 8 },
325 [SCSCR] = { 0x04, 8 },
326 [SCxTDR] = { 0x06, 8 },
327 [SCxSR] = { 0x08, 16 },
328 [SCxRDR] = { 0x0a, 8 },
329 [SCFCR] = { 0x0c, 8 },
330 [SCFDR] = { 0x0e, 16 },
331 },
332 .fifosize = 16,
333 .overrun_reg = SCLSR,
334 .overrun_mask = SCLSR_ORER,
335 .sampling_rate_mask = SCI_SR(32),
336 .error_mask = SCIF_DEFAULT_ERROR_MASK,
337 .error_clear = SCIF_ERROR_CLEAR,
338 },
339
340 /*
341 * Common SH-4(A) SCIF(B) definitions.
342 */
343 [SCIx_SH4_SCIF_REGTYPE] = {
344 .regs = {
345 [SCSMR] = { 0x00, 16 },
346 [SCBRR] = { 0x04, 8 },
347 [SCSCR] = { 0x08, 16 },
348 [SCxTDR] = { 0x0c, 8 },
349 [SCxSR] = { 0x10, 16 },
350 [SCxRDR] = { 0x14, 8 },
351 [SCFCR] = { 0x18, 16 },
352 [SCFDR] = { 0x1c, 16 },
353 [SCSPTR] = { 0x20, 16 },
354 [SCLSR] = { 0x24, 16 },
355 },
356 .fifosize = 16,
357 .overrun_reg = SCLSR,
358 .overrun_mask = SCLSR_ORER,
359 .sampling_rate_mask = SCI_SR(32),
360 .error_mask = SCIF_DEFAULT_ERROR_MASK,
361 .error_clear = SCIF_ERROR_CLEAR,
362 },
363
364 /*
365 * Common SCIF definitions for ports with a Baud Rate Generator for
366 * External Clock (BRG).
367 */
368 [SCIx_SH4_SCIF_BRG_REGTYPE] = {
369 .regs = {
370 [SCSMR] = { 0x00, 16 },
371 [SCBRR] = { 0x04, 8 },
372 [SCSCR] = { 0x08, 16 },
373 [SCxTDR] = { 0x0c, 8 },
374 [SCxSR] = { 0x10, 16 },
375 [SCxRDR] = { 0x14, 8 },
376 [SCFCR] = { 0x18, 16 },
377 [SCFDR] = { 0x1c, 16 },
378 [SCSPTR] = { 0x20, 16 },
379 [SCLSR] = { 0x24, 16 },
380 [SCDL] = { 0x30, 16 },
381 [SCCKS] = { 0x34, 16 },
382 },
383 .fifosize = 16,
384 .overrun_reg = SCLSR,
385 .overrun_mask = SCLSR_ORER,
386 .sampling_rate_mask = SCI_SR(32),
387 .error_mask = SCIF_DEFAULT_ERROR_MASK,
388 .error_clear = SCIF_ERROR_CLEAR,
389 },
390
391 /*
392 * Common HSCIF definitions.
393 */
394 [SCIx_HSCIF_REGTYPE] = {
395 .regs = {
396 [SCSMR] = { 0x00, 16 },
397 [SCBRR] = { 0x04, 8 },
398 [SCSCR] = { 0x08, 16 },
399 [SCxTDR] = { 0x0c, 8 },
400 [SCxSR] = { 0x10, 16 },
401 [SCxRDR] = { 0x14, 8 },
402 [SCFCR] = { 0x18, 16 },
403 [SCFDR] = { 0x1c, 16 },
404 [SCSPTR] = { 0x20, 16 },
405 [SCLSR] = { 0x24, 16 },
406 [HSSRR] = { 0x40, 16 },
407 [SCDL] = { 0x30, 16 },
408 [SCCKS] = { 0x34, 16 },
409 [HSRTRGR] = { 0x54, 16 },
410 [HSTTRGR] = { 0x58, 16 },
411 },
412 .fifosize = 128,
413 .overrun_reg = SCLSR,
414 .overrun_mask = SCLSR_ORER,
415 .sampling_rate_mask = SCI_SR_RANGE(8, 32),
416 .error_mask = SCIF_DEFAULT_ERROR_MASK,
417 .error_clear = SCIF_ERROR_CLEAR,
418 },
419
420 /*
421 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
422 * register.
423 */
424 [SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
425 .regs = {
426 [SCSMR] = { 0x00, 16 },
427 [SCBRR] = { 0x04, 8 },
428 [SCSCR] = { 0x08, 16 },
429 [SCxTDR] = { 0x0c, 8 },
430 [SCxSR] = { 0x10, 16 },
431 [SCxRDR] = { 0x14, 8 },
432 [SCFCR] = { 0x18, 16 },
433 [SCFDR] = { 0x1c, 16 },
434 [SCLSR] = { 0x24, 16 },
435 },
436 .fifosize = 16,
437 .overrun_reg = SCLSR,
438 .overrun_mask = SCLSR_ORER,
439 .sampling_rate_mask = SCI_SR(32),
440 .error_mask = SCIF_DEFAULT_ERROR_MASK,
441 .error_clear = SCIF_ERROR_CLEAR,
442 },
443
444 /*
445 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
446 * count registers.
447 */
448 [SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
449 .regs = {
450 [SCSMR] = { 0x00, 16 },
451 [SCBRR] = { 0x04, 8 },
452 [SCSCR] = { 0x08, 16 },
453 [SCxTDR] = { 0x0c, 8 },
454 [SCxSR] = { 0x10, 16 },
455 [SCxRDR] = { 0x14, 8 },
456 [SCFCR] = { 0x18, 16 },
457 [SCFDR] = { 0x1c, 16 },
458 [SCTFDR] = { 0x1c, 16 }, /* aliased to SCFDR */
459 [SCRFDR] = { 0x20, 16 },
460 [SCSPTR] = { 0x24, 16 },
461 [SCLSR] = { 0x28, 16 },
462 },
463 .fifosize = 16,
464 .overrun_reg = SCLSR,
465 .overrun_mask = SCLSR_ORER,
466 .sampling_rate_mask = SCI_SR(32),
467 .error_mask = SCIF_DEFAULT_ERROR_MASK,
468 .error_clear = SCIF_ERROR_CLEAR,
469 },
470
471 /*
472 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
473 * registers.
474 */
475 [SCIx_SH7705_SCIF_REGTYPE] = {
476 .regs = {
477 [SCSMR] = { 0x00, 16 },
478 [SCBRR] = { 0x04, 8 },
479 [SCSCR] = { 0x08, 16 },
480 [SCxTDR] = { 0x20, 8 },
481 [SCxSR] = { 0x14, 16 },
482 [SCxRDR] = { 0x24, 8 },
483 [SCFCR] = { 0x18, 16 },
484 [SCFDR] = { 0x1c, 16 },
485 },
486 .fifosize = 64,
487 .overrun_reg = SCxSR,
488 .overrun_mask = SCIFA_ORER,
489 .sampling_rate_mask = SCI_SR(16),
490 .error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
491 .error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
492 },
493 };
494
495 #define sci_getreg(up, offset) (&to_sci_port(up)->params->regs[offset])
496
497 /*
498 * The "offset" here is rather misleading, in that it refers to an enum
499 * value relative to the port mapping rather than the fixed offset
500 * itself, which needs to be manually retrieved from the platform's
501 * register map for the given port.
502 */
503 static unsigned int sci_serial_in(struct uart_port *p, int offset)
504 {
505 const struct plat_sci_reg *reg = sci_getreg(p, offset);
506
507 if (reg->size == 8)
508 return ioread8(p->membase + (reg->offset << p->regshift));
509 else if (reg->size == 16)
510 return ioread16(p->membase + (reg->offset << p->regshift));
511 else
512 WARN(1, "Invalid register access\n");
513
514 return 0;
515 }
516
517 static void sci_serial_out(struct uart_port *p, int offset, int value)
518 {
519 const struct plat_sci_reg *reg = sci_getreg(p, offset);
520
521 if (reg->size == 8)
522 iowrite8(value, p->membase + (reg->offset << p->regshift));
523 else if (reg->size == 16)
524 iowrite16(value, p->membase + (reg->offset << p->regshift));
525 else
526 WARN(1, "Invalid register access\n");
527 }
528
529 static void sci_port_enable(struct sci_port *sci_port)
530 {
531 unsigned int i;
532
533 if (!sci_port->port.dev)
534 return;
535
536 pm_runtime_get_sync(sci_port->port.dev);
537
538 for (i = 0; i < SCI_NUM_CLKS; i++) {
539 clk_prepare_enable(sci_port->clks[i]);
540 sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
541 }
542 sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
543 }
544
545 static void sci_port_disable(struct sci_port *sci_port)
546 {
547 unsigned int i;
548
549 if (!sci_port->port.dev)
550 return;
551
552 for (i = SCI_NUM_CLKS; i-- > 0; )
553 clk_disable_unprepare(sci_port->clks[i]);
554
555 pm_runtime_put_sync(sci_port->port.dev);
556 }
557
558 static inline unsigned long port_rx_irq_mask(struct uart_port *port)
559 {
560 /*
561 * Not all ports (such as SCIFA) will support REIE. Rather than
562 * special-casing the port type, we check the port initialization
563 * IRQ enable mask to see whether the IRQ is desired at all. If
564 * it's unset, it's logically inferred that there's no point in
565 * testing for it.
566 */
567 return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
568 }
569
570 static void sci_start_tx(struct uart_port *port)
571 {
572 struct sci_port *s = to_sci_port(port);
573 unsigned short ctrl;
574
575 #ifdef CONFIG_SERIAL_SH_SCI_DMA
576 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
577 u16 new, scr = serial_port_in(port, SCSCR);
578 if (s->chan_tx)
579 new = scr | SCSCR_TDRQE;
580 else
581 new = scr & ~SCSCR_TDRQE;
582 if (new != scr)
583 serial_port_out(port, SCSCR, new);
584 }
585
586 if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
587 dma_submit_error(s->cookie_tx)) {
588 s->cookie_tx = 0;
589 schedule_work(&s->work_tx);
590 }
591 #endif
592
593 if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
594 /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
595 ctrl = serial_port_in(port, SCSCR);
596 serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
597 }
598 }
599
600 static void sci_stop_tx(struct uart_port *port)
601 {
602 unsigned short ctrl;
603
604 /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
605 ctrl = serial_port_in(port, SCSCR);
606
607 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
608 ctrl &= ~SCSCR_TDRQE;
609
610 ctrl &= ~SCSCR_TIE;
611
612 serial_port_out(port, SCSCR, ctrl);
613 }
614
615 static void sci_start_rx(struct uart_port *port)
616 {
617 unsigned short ctrl;
618
619 ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
620
621 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
622 ctrl &= ~SCSCR_RDRQE;
623
624 serial_port_out(port, SCSCR, ctrl);
625 }
626
627 static void sci_stop_rx(struct uart_port *port)
628 {
629 unsigned short ctrl;
630
631 ctrl = serial_port_in(port, SCSCR);
632
633 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
634 ctrl &= ~SCSCR_RDRQE;
635
636 ctrl &= ~port_rx_irq_mask(port);
637
638 serial_port_out(port, SCSCR, ctrl);
639 }
640
641 static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
642 {
643 if (port->type == PORT_SCI) {
644 /* Just store the mask */
645 serial_port_out(port, SCxSR, mask);
646 } else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
647 /* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
648 /* Only clear the status bits we want to clear */
649 serial_port_out(port, SCxSR,
650 serial_port_in(port, SCxSR) & mask);
651 } else {
652 /* Store the mask, clear parity/framing errors */
653 serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
654 }
655 }
656
657 #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
658 defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
659
660 #ifdef CONFIG_CONSOLE_POLL
661 static int sci_poll_get_char(struct uart_port *port)
662 {
663 unsigned short status;
664 int c;
665
666 do {
667 status = serial_port_in(port, SCxSR);
668 if (status & SCxSR_ERRORS(port)) {
669 sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
670 continue;
671 }
672 break;
673 } while (1);
674
675 if (!(status & SCxSR_RDxF(port)))
676 return NO_POLL_CHAR;
677
678 c = serial_port_in(port, SCxRDR);
679
680 /* Dummy read */
681 serial_port_in(port, SCxSR);
682 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
683
684 return c;
685 }
686 #endif
687
688 static void sci_poll_put_char(struct uart_port *port, unsigned char c)
689 {
690 unsigned short status;
691
692 do {
693 status = serial_port_in(port, SCxSR);
694 } while (!(status & SCxSR_TDxE(port)));
695
696 serial_port_out(port, SCxTDR, c);
697 sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
698 }
699 #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
700 CONFIG_SERIAL_SH_SCI_EARLYCON */
701
702 static void sci_init_pins(struct uart_port *port, unsigned int cflag)
703 {
704 struct sci_port *s = to_sci_port(port);
705
706 /*
707 * Use port-specific handler if provided.
708 */
709 if (s->cfg->ops && s->cfg->ops->init_pins) {
710 s->cfg->ops->init_pins(port, cflag);
711 return;
712 }
713
714 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
715 u16 data = serial_port_in(port, SCPDR);
716 u16 ctrl = serial_port_in(port, SCPCR);
717
718 /* Enable RXD and TXD pin functions */
719 ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
720 if (to_sci_port(port)->has_rtscts) {
721 /* RTS# is output, active low, unless autorts */
722 if (!(port->mctrl & TIOCM_RTS)) {
723 ctrl |= SCPCR_RTSC;
724 data |= SCPDR_RTSD;
725 } else if (!s->autorts) {
726 ctrl |= SCPCR_RTSC;
727 data &= ~SCPDR_RTSD;
728 } else {
729 /* Enable RTS# pin function */
730 ctrl &= ~SCPCR_RTSC;
731 }
732 /* Enable CTS# pin function */
733 ctrl &= ~SCPCR_CTSC;
734 }
735 serial_port_out(port, SCPDR, data);
736 serial_port_out(port, SCPCR, ctrl);
737 } else if (sci_getreg(port, SCSPTR)->size) {
738 u16 status = serial_port_in(port, SCSPTR);
739
740 /* RTS# is always output; and active low, unless autorts */
741 status |= SCSPTR_RTSIO;
742 if (!(port->mctrl & TIOCM_RTS))
743 status |= SCSPTR_RTSDT;
744 else if (!s->autorts)
745 status &= ~SCSPTR_RTSDT;
746 /* CTS# and SCK are inputs */
747 status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
748 serial_port_out(port, SCSPTR, status);
749 }
750 }
751
752 static int sci_txfill(struct uart_port *port)
753 {
754 struct sci_port *s = to_sci_port(port);
755 unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
756 const struct plat_sci_reg *reg;
757
758 reg = sci_getreg(port, SCTFDR);
759 if (reg->size)
760 return serial_port_in(port, SCTFDR) & fifo_mask;
761
762 reg = sci_getreg(port, SCFDR);
763 if (reg->size)
764 return serial_port_in(port, SCFDR) >> 8;
765
766 return !(serial_port_in(port, SCxSR) & SCI_TDRE);
767 }
768
769 static int sci_txroom(struct uart_port *port)
770 {
771 return port->fifosize - sci_txfill(port);
772 }
773
774 static int sci_rxfill(struct uart_port *port)
775 {
776 struct sci_port *s = to_sci_port(port);
777 unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
778 const struct plat_sci_reg *reg;
779
780 reg = sci_getreg(port, SCRFDR);
781 if (reg->size)
782 return serial_port_in(port, SCRFDR) & fifo_mask;
783
784 reg = sci_getreg(port, SCFDR);
785 if (reg->size)
786 return serial_port_in(port, SCFDR) & fifo_mask;
787
788 return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
789 }
790
791 /* ********************************************************************** *
792 * the interrupt related routines *
793 * ********************************************************************** */
794
795 static void sci_transmit_chars(struct uart_port *port)
796 {
797 struct circ_buf *xmit = &port->state->xmit;
798 unsigned int stopped = uart_tx_stopped(port);
799 unsigned short status;
800 unsigned short ctrl;
801 int count;
802
803 status = serial_port_in(port, SCxSR);
804 if (!(status & SCxSR_TDxE(port))) {
805 ctrl = serial_port_in(port, SCSCR);
806 if (uart_circ_empty(xmit))
807 ctrl &= ~SCSCR_TIE;
808 else
809 ctrl |= SCSCR_TIE;
810 serial_port_out(port, SCSCR, ctrl);
811 return;
812 }
813
814 count = sci_txroom(port);
815
816 do {
817 unsigned char c;
818
819 if (port->x_char) {
820 c = port->x_char;
821 port->x_char = 0;
822 } else if (!uart_circ_empty(xmit) && !stopped) {
823 c = xmit->buf[xmit->tail];
824 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
825 } else {
826 break;
827 }
828
829 serial_port_out(port, SCxTDR, c);
830
831 port->icount.tx++;
832 } while (--count > 0);
833
834 sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
835
836 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
837 uart_write_wakeup(port);
838 if (uart_circ_empty(xmit))
839 sci_stop_tx(port);
840
841 }
842
843 /* On SH3, SCIF may read end-of-break as a space->mark char */
844 #define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); })
845
846 static void sci_receive_chars(struct uart_port *port)
847 {
848 struct tty_port *tport = &port->state->port;
849 int i, count, copied = 0;
850 unsigned short status;
851 unsigned char flag;
852
853 status = serial_port_in(port, SCxSR);
854 if (!(status & SCxSR_RDxF(port)))
855 return;
856
857 while (1) {
858 /* Don't copy more bytes than there is room for in the buffer */
859 count = tty_buffer_request_room(tport, sci_rxfill(port));
860
861 /* If for any reason we can't copy more data, we're done! */
862 if (count == 0)
863 break;
864
865 if (port->type == PORT_SCI) {
866 char c = serial_port_in(port, SCxRDR);
867 if (uart_handle_sysrq_char(port, c))
868 count = 0;
869 else
870 tty_insert_flip_char(tport, c, TTY_NORMAL);
871 } else {
872 for (i = 0; i < count; i++) {
873 char c;
874
875 if (port->type == PORT_SCIF ||
876 port->type == PORT_HSCIF) {
877 status = serial_port_in(port, SCxSR);
878 c = serial_port_in(port, SCxRDR);
879 } else {
880 c = serial_port_in(port, SCxRDR);
881 status = serial_port_in(port, SCxSR);
882 }
883 if (uart_handle_sysrq_char(port, c)) {
884 count--; i--;
885 continue;
886 }
887
888 /* Store data and status */
889 if (status & SCxSR_FER(port)) {
890 flag = TTY_FRAME;
891 port->icount.frame++;
892 dev_notice(port->dev, "frame error\n");
893 } else if (status & SCxSR_PER(port)) {
894 flag = TTY_PARITY;
895 port->icount.parity++;
896 dev_notice(port->dev, "parity error\n");
897 } else
898 flag = TTY_NORMAL;
899
900 tty_insert_flip_char(tport, c, flag);
901 }
902 }
903
904 serial_port_in(port, SCxSR); /* dummy read */
905 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
906
907 copied += count;
908 port->icount.rx += count;
909 }
910
911 if (copied) {
912 /* Tell the rest of the system the news. New characters! */
913 tty_flip_buffer_push(tport);
914 } else {
915 /* TTY buffers full; read from RX reg to prevent lockup */
916 serial_port_in(port, SCxRDR);
917 serial_port_in(port, SCxSR); /* dummy read */
918 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
919 }
920 }
921
922 static int sci_handle_errors(struct uart_port *port)
923 {
924 int copied = 0;
925 unsigned short status = serial_port_in(port, SCxSR);
926 struct tty_port *tport = &port->state->port;
927 struct sci_port *s = to_sci_port(port);
928
929 /* Handle overruns */
930 if (status & s->params->overrun_mask) {
931 port->icount.overrun++;
932
933 /* overrun error */
934 if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
935 copied++;
936
937 dev_notice(port->dev, "overrun error\n");
938 }
939
940 if (status & SCxSR_FER(port)) {
941 /* frame error */
942 port->icount.frame++;
943
944 if (tty_insert_flip_char(tport, 0, TTY_FRAME))
945 copied++;
946
947 dev_notice(port->dev, "frame error\n");
948 }
949
950 if (status & SCxSR_PER(port)) {
951 /* parity error */
952 port->icount.parity++;
953
954 if (tty_insert_flip_char(tport, 0, TTY_PARITY))
955 copied++;
956
957 dev_notice(port->dev, "parity error\n");
958 }
959
960 if (copied)
961 tty_flip_buffer_push(tport);
962
963 return copied;
964 }
965
966 static int sci_handle_fifo_overrun(struct uart_port *port)
967 {
968 struct tty_port *tport = &port->state->port;
969 struct sci_port *s = to_sci_port(port);
970 const struct plat_sci_reg *reg;
971 int copied = 0;
972 u16 status;
973
974 reg = sci_getreg(port, s->params->overrun_reg);
975 if (!reg->size)
976 return 0;
977
978 status = serial_port_in(port, s->params->overrun_reg);
979 if (status & s->params->overrun_mask) {
980 status &= ~s->params->overrun_mask;
981 serial_port_out(port, s->params->overrun_reg, status);
982
983 port->icount.overrun++;
984
985 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
986 tty_flip_buffer_push(tport);
987
988 dev_dbg(port->dev, "overrun error\n");
989 copied++;
990 }
991
992 return copied;
993 }
994
995 static int sci_handle_breaks(struct uart_port *port)
996 {
997 int copied = 0;
998 unsigned short status = serial_port_in(port, SCxSR);
999 struct tty_port *tport = &port->state->port;
1000
1001 if (uart_handle_break(port))
1002 return 0;
1003
1004 if (status & SCxSR_BRK(port)) {
1005 port->icount.brk++;
1006
1007 /* Notify of BREAK */
1008 if (tty_insert_flip_char(tport, 0, TTY_BREAK))
1009 copied++;
1010
1011 dev_dbg(port->dev, "BREAK detected\n");
1012 }
1013
1014 if (copied)
1015 tty_flip_buffer_push(tport);
1016
1017 copied += sci_handle_fifo_overrun(port);
1018
1019 return copied;
1020 }
1021
1022 static int scif_set_rtrg(struct uart_port *port, int rx_trig)
1023 {
1024 unsigned int bits;
1025
1026 if (rx_trig < 1)
1027 rx_trig = 1;
1028 if (rx_trig >= port->fifosize)
1029 rx_trig = port->fifosize;
1030
1031 /* HSCIF can be set to an arbitrary level. */
1032 if (sci_getreg(port, HSRTRGR)->size) {
1033 serial_port_out(port, HSRTRGR, rx_trig);
1034 return rx_trig;
1035 }
1036
1037 switch (port->type) {
1038 case PORT_SCIF:
1039 if (rx_trig < 4) {
1040 bits = 0;
1041 rx_trig = 1;
1042 } else if (rx_trig < 8) {
1043 bits = SCFCR_RTRG0;
1044 rx_trig = 4;
1045 } else if (rx_trig < 14) {
1046 bits = SCFCR_RTRG1;
1047 rx_trig = 8;
1048 } else {
1049 bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1050 rx_trig = 14;
1051 }
1052 break;
1053 case PORT_SCIFA:
1054 case PORT_SCIFB:
1055 if (rx_trig < 16) {
1056 bits = 0;
1057 rx_trig = 1;
1058 } else if (rx_trig < 32) {
1059 bits = SCFCR_RTRG0;
1060 rx_trig = 16;
1061 } else if (rx_trig < 48) {
1062 bits = SCFCR_RTRG1;
1063 rx_trig = 32;
1064 } else {
1065 bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1066 rx_trig = 48;
1067 }
1068 break;
1069 default:
1070 WARN(1, "unknown FIFO configuration");
1071 return 1;
1072 }
1073
1074 serial_port_out(port, SCFCR,
1075 (serial_port_in(port, SCFCR) &
1076 ~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1077
1078 return rx_trig;
1079 }
1080
1081 static int scif_rtrg_enabled(struct uart_port *port)
1082 {
1083 if (sci_getreg(port, HSRTRGR)->size)
1084 return serial_port_in(port, HSRTRGR) != 0;
1085 else
1086 return (serial_port_in(port, SCFCR) &
1087 (SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1088 }
1089
1090 static void rx_fifo_timer_fn(struct timer_list *t)
1091 {
1092 struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1093 struct uart_port *port = &s->port;
1094
1095 dev_dbg(port->dev, "Rx timed out\n");
1096 scif_set_rtrg(port, 1);
1097 }
1098
1099 static ssize_t rx_fifo_trigger_show(struct device *dev,
1100 struct device_attribute *attr, char *buf)
1101 {
1102 struct uart_port *port = dev_get_drvdata(dev);
1103 struct sci_port *sci = to_sci_port(port);
1104
1105 return sprintf(buf, "%d\n", sci->rx_trigger);
1106 }
1107
1108 static ssize_t rx_fifo_trigger_store(struct device *dev,
1109 struct device_attribute *attr,
1110 const char *buf, size_t count)
1111 {
1112 struct uart_port *port = dev_get_drvdata(dev);
1113 struct sci_port *sci = to_sci_port(port);
1114 int ret;
1115 long r;
1116
1117 ret = kstrtol(buf, 0, &r);
1118 if (ret)
1119 return ret;
1120
1121 sci->rx_trigger = scif_set_rtrg(port, r);
1122 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1123 scif_set_rtrg(port, 1);
1124
1125 return count;
1126 }
1127
1128 static DEVICE_ATTR_RW(rx_fifo_trigger);
1129
1130 static ssize_t rx_fifo_timeout_show(struct device *dev,
1131 struct device_attribute *attr,
1132 char *buf)
1133 {
1134 struct uart_port *port = dev_get_drvdata(dev);
1135 struct sci_port *sci = to_sci_port(port);
1136 int v;
1137
1138 if (port->type == PORT_HSCIF)
1139 v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1140 else
1141 v = sci->rx_fifo_timeout;
1142
1143 return sprintf(buf, "%d\n", v);
1144 }
1145
1146 static ssize_t rx_fifo_timeout_store(struct device *dev,
1147 struct device_attribute *attr,
1148 const char *buf,
1149 size_t count)
1150 {
1151 struct uart_port *port = dev_get_drvdata(dev);
1152 struct sci_port *sci = to_sci_port(port);
1153 int ret;
1154 long r;
1155
1156 ret = kstrtol(buf, 0, &r);
1157 if (ret)
1158 return ret;
1159
1160 if (port->type == PORT_HSCIF) {
1161 if (r < 0 || r > 3)
1162 return -EINVAL;
1163 sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1164 } else {
1165 sci->rx_fifo_timeout = r;
1166 scif_set_rtrg(port, 1);
1167 if (r > 0)
1168 timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1169 }
1170
1171 return count;
1172 }
1173
1174 static DEVICE_ATTR_RW(rx_fifo_timeout);
1175
1176
1177 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1178 static void sci_dma_tx_complete(void *arg)
1179 {
1180 struct sci_port *s = arg;
1181 struct uart_port *port = &s->port;
1182 struct circ_buf *xmit = &port->state->xmit;
1183 unsigned long flags;
1184
1185 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1186
1187 spin_lock_irqsave(&port->lock, flags);
1188
1189 xmit->tail += s->tx_dma_len;
1190 xmit->tail &= UART_XMIT_SIZE - 1;
1191
1192 port->icount.tx += s->tx_dma_len;
1193
1194 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1195 uart_write_wakeup(port);
1196
1197 if (!uart_circ_empty(xmit)) {
1198 s->cookie_tx = 0;
1199 schedule_work(&s->work_tx);
1200 } else {
1201 s->cookie_tx = -EINVAL;
1202 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1203 u16 ctrl = serial_port_in(port, SCSCR);
1204 serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1205 }
1206 }
1207
1208 spin_unlock_irqrestore(&port->lock, flags);
1209 }
1210
1211 /* Locking: called with port lock held */
1212 static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1213 {
1214 struct uart_port *port = &s->port;
1215 struct tty_port *tport = &port->state->port;
1216 int copied;
1217
1218 copied = tty_insert_flip_string(tport, buf, count);
1219 if (copied < count)
1220 port->icount.buf_overrun++;
1221
1222 port->icount.rx += copied;
1223
1224 return copied;
1225 }
1226
1227 static int sci_dma_rx_find_active(struct sci_port *s)
1228 {
1229 unsigned int i;
1230
1231 for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1232 if (s->active_rx == s->cookie_rx[i])
1233 return i;
1234
1235 return -1;
1236 }
1237
1238 static void sci_dma_rx_chan_invalidate(struct sci_port *s)
1239 {
1240 unsigned int i;
1241
1242 s->chan_rx = NULL;
1243 for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1244 s->cookie_rx[i] = -EINVAL;
1245 s->active_rx = 0;
1246 }
1247
1248 static void sci_dma_rx_release(struct sci_port *s)
1249 {
1250 struct dma_chan *chan = s->chan_rx_saved;
1251
1252 s->chan_rx_saved = NULL;
1253 sci_dma_rx_chan_invalidate(s);
1254 dmaengine_terminate_sync(chan);
1255 dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1256 sg_dma_address(&s->sg_rx[0]));
1257 dma_release_channel(chan);
1258 }
1259
1260 static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1261 {
1262 long sec = usec / 1000000;
1263 long nsec = (usec % 1000000) * 1000;
1264 ktime_t t = ktime_set(sec, nsec);
1265
1266 hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1267 }
1268
1269 static void sci_dma_rx_reenable_irq(struct sci_port *s)
1270 {
1271 struct uart_port *port = &s->port;
1272 u16 scr;
1273
1274 /* Direct new serial port interrupts back to CPU */
1275 scr = serial_port_in(port, SCSCR);
1276 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1277 scr &= ~SCSCR_RDRQE;
1278 enable_irq(s->irqs[SCIx_RXI_IRQ]);
1279 }
1280 serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1281 }
1282
1283 static void sci_dma_rx_complete(void *arg)
1284 {
1285 struct sci_port *s = arg;
1286 struct dma_chan *chan = s->chan_rx;
1287 struct uart_port *port = &s->port;
1288 struct dma_async_tx_descriptor *desc;
1289 unsigned long flags;
1290 int active, count = 0;
1291
1292 dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1293 s->active_rx);
1294
1295 spin_lock_irqsave(&port->lock, flags);
1296
1297 active = sci_dma_rx_find_active(s);
1298 if (active >= 0)
1299 count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1300
1301 start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1302
1303 if (count)
1304 tty_flip_buffer_push(&port->state->port);
1305
1306 desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1307 DMA_DEV_TO_MEM,
1308 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1309 if (!desc)
1310 goto fail;
1311
1312 desc->callback = sci_dma_rx_complete;
1313 desc->callback_param = s;
1314 s->cookie_rx[active] = dmaengine_submit(desc);
1315 if (dma_submit_error(s->cookie_rx[active]))
1316 goto fail;
1317
1318 s->active_rx = s->cookie_rx[!active];
1319
1320 dma_async_issue_pending(chan);
1321
1322 spin_unlock_irqrestore(&port->lock, flags);
1323 dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1324 __func__, s->cookie_rx[active], active, s->active_rx);
1325 return;
1326
1327 fail:
1328 spin_unlock_irqrestore(&port->lock, flags);
1329 dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1330 /* Switch to PIO */
1331 spin_lock_irqsave(&port->lock, flags);
1332 dmaengine_terminate_async(chan);
1333 sci_dma_rx_chan_invalidate(s);
1334 sci_dma_rx_reenable_irq(s);
1335 spin_unlock_irqrestore(&port->lock, flags);
1336 }
1337
1338 static void sci_dma_tx_release(struct sci_port *s)
1339 {
1340 struct dma_chan *chan = s->chan_tx_saved;
1341
1342 cancel_work_sync(&s->work_tx);
1343 s->chan_tx_saved = s->chan_tx = NULL;
1344 s->cookie_tx = -EINVAL;
1345 dmaengine_terminate_sync(chan);
1346 dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1347 DMA_TO_DEVICE);
1348 dma_release_channel(chan);
1349 }
1350
1351 static int sci_dma_rx_submit(struct sci_port *s, bool port_lock_held)
1352 {
1353 struct dma_chan *chan = s->chan_rx;
1354 struct uart_port *port = &s->port;
1355 unsigned long flags;
1356 int i;
1357
1358 for (i = 0; i < 2; i++) {
1359 struct scatterlist *sg = &s->sg_rx[i];
1360 struct dma_async_tx_descriptor *desc;
1361
1362 desc = dmaengine_prep_slave_sg(chan,
1363 sg, 1, DMA_DEV_TO_MEM,
1364 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1365 if (!desc)
1366 goto fail;
1367
1368 desc->callback = sci_dma_rx_complete;
1369 desc->callback_param = s;
1370 s->cookie_rx[i] = dmaengine_submit(desc);
1371 if (dma_submit_error(s->cookie_rx[i]))
1372 goto fail;
1373
1374 }
1375
1376 s->active_rx = s->cookie_rx[0];
1377
1378 dma_async_issue_pending(chan);
1379 return 0;
1380
1381 fail:
1382 /* Switch to PIO */
1383 if (!port_lock_held)
1384 spin_lock_irqsave(&port->lock, flags);
1385 if (i)
1386 dmaengine_terminate_async(chan);
1387 sci_dma_rx_chan_invalidate(s);
1388 sci_start_rx(port);
1389 if (!port_lock_held)
1390 spin_unlock_irqrestore(&port->lock, flags);
1391 return -EAGAIN;
1392 }
1393
1394 static void sci_dma_tx_work_fn(struct work_struct *work)
1395 {
1396 struct sci_port *s = container_of(work, struct sci_port, work_tx);
1397 struct dma_async_tx_descriptor *desc;
1398 struct dma_chan *chan = s->chan_tx;
1399 struct uart_port *port = &s->port;
1400 struct circ_buf *xmit = &port->state->xmit;
1401 unsigned long flags;
1402 dma_addr_t buf;
1403 int head, tail;
1404
1405 /*
1406 * DMA is idle now.
1407 * Port xmit buffer is already mapped, and it is one page... Just adjust
1408 * offsets and lengths. Since it is a circular buffer, we have to
1409 * transmit till the end, and then the rest. Take the port lock to get a
1410 * consistent xmit buffer state.
1411 */
1412 spin_lock_irq(&port->lock);
1413 head = xmit->head;
1414 tail = xmit->tail;
1415 buf = s->tx_dma_addr + (tail & (UART_XMIT_SIZE - 1));
1416 s->tx_dma_len = min_t(unsigned int,
1417 CIRC_CNT(head, tail, UART_XMIT_SIZE),
1418 CIRC_CNT_TO_END(head, tail, UART_XMIT_SIZE));
1419 if (!s->tx_dma_len) {
1420 /* Transmit buffer has been flushed */
1421 spin_unlock_irq(&port->lock);
1422 return;
1423 }
1424
1425 desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1426 DMA_MEM_TO_DEV,
1427 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1428 if (!desc) {
1429 spin_unlock_irq(&port->lock);
1430 dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1431 goto switch_to_pio;
1432 }
1433
1434 dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1435 DMA_TO_DEVICE);
1436
1437 desc->callback = sci_dma_tx_complete;
1438 desc->callback_param = s;
1439 s->cookie_tx = dmaengine_submit(desc);
1440 if (dma_submit_error(s->cookie_tx)) {
1441 spin_unlock_irq(&port->lock);
1442 dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1443 goto switch_to_pio;
1444 }
1445
1446 spin_unlock_irq(&port->lock);
1447 dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1448 __func__, xmit->buf, tail, head, s->cookie_tx);
1449
1450 dma_async_issue_pending(chan);
1451 return;
1452
1453 switch_to_pio:
1454 spin_lock_irqsave(&port->lock, flags);
1455 s->chan_tx = NULL;
1456 sci_start_tx(port);
1457 spin_unlock_irqrestore(&port->lock, flags);
1458 return;
1459 }
1460
1461 static enum hrtimer_restart sci_dma_rx_timer_fn(struct hrtimer *t)
1462 {
1463 struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1464 struct dma_chan *chan = s->chan_rx;
1465 struct uart_port *port = &s->port;
1466 struct dma_tx_state state;
1467 enum dma_status status;
1468 unsigned long flags;
1469 unsigned int read;
1470 int active, count;
1471
1472 dev_dbg(port->dev, "DMA Rx timed out\n");
1473
1474 spin_lock_irqsave(&port->lock, flags);
1475
1476 active = sci_dma_rx_find_active(s);
1477 if (active < 0) {
1478 spin_unlock_irqrestore(&port->lock, flags);
1479 return HRTIMER_NORESTART;
1480 }
1481
1482 status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1483 if (status == DMA_COMPLETE) {
1484 spin_unlock_irqrestore(&port->lock, flags);
1485 dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1486 s->active_rx, active);
1487
1488 /* Let packet complete handler take care of the packet */
1489 return HRTIMER_NORESTART;
1490 }
1491
1492 dmaengine_pause(chan);
1493
1494 /*
1495 * sometimes DMA transfer doesn't stop even if it is stopped and
1496 * data keeps on coming until transaction is complete so check
1497 * for DMA_COMPLETE again
1498 * Let packet complete handler take care of the packet
1499 */
1500 status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1501 if (status == DMA_COMPLETE) {
1502 spin_unlock_irqrestore(&port->lock, flags);
1503 dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1504 return HRTIMER_NORESTART;
1505 }
1506
1507 /* Handle incomplete DMA receive */
1508 dmaengine_terminate_async(s->chan_rx);
1509 read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1510
1511 if (read) {
1512 count = sci_dma_rx_push(s, s->rx_buf[active], read);
1513 if (count)
1514 tty_flip_buffer_push(&port->state->port);
1515 }
1516
1517 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1518 sci_dma_rx_submit(s, true);
1519
1520 sci_dma_rx_reenable_irq(s);
1521
1522 spin_unlock_irqrestore(&port->lock, flags);
1523
1524 return HRTIMER_NORESTART;
1525 }
1526
1527 static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1528 enum dma_transfer_direction dir)
1529 {
1530 struct dma_chan *chan;
1531 struct dma_slave_config cfg;
1532 int ret;
1533
1534 chan = dma_request_slave_channel(port->dev,
1535 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1536 if (!chan) {
1537 dev_dbg(port->dev, "dma_request_slave_channel failed\n");
1538 return NULL;
1539 }
1540
1541 memset(&cfg, 0, sizeof(cfg));
1542 cfg.direction = dir;
1543 if (dir == DMA_MEM_TO_DEV) {
1544 cfg.dst_addr = port->mapbase +
1545 (sci_getreg(port, SCxTDR)->offset << port->regshift);
1546 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1547 } else {
1548 cfg.src_addr = port->mapbase +
1549 (sci_getreg(port, SCxRDR)->offset << port->regshift);
1550 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1551 }
1552
1553 ret = dmaengine_slave_config(chan, &cfg);
1554 if (ret) {
1555 dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1556 dma_release_channel(chan);
1557 return NULL;
1558 }
1559
1560 return chan;
1561 }
1562
1563 static void sci_request_dma(struct uart_port *port)
1564 {
1565 struct sci_port *s = to_sci_port(port);
1566 struct dma_chan *chan;
1567
1568 dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1569
1570 /*
1571 * DMA on console may interfere with Kernel log messages which use
1572 * plain putchar(). So, simply don't use it with a console.
1573 */
1574 if (uart_console(port))
1575 return;
1576
1577 if (!port->dev->of_node)
1578 return;
1579
1580 s->cookie_tx = -EINVAL;
1581
1582 /*
1583 * Don't request a dma channel if no channel was specified
1584 * in the device tree.
1585 */
1586 if (!of_find_property(port->dev->of_node, "dmas", NULL))
1587 return;
1588
1589 chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1590 dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1591 if (chan) {
1592 /* UART circular tx buffer is an aligned page. */
1593 s->tx_dma_addr = dma_map_single(chan->device->dev,
1594 port->state->xmit.buf,
1595 UART_XMIT_SIZE,
1596 DMA_TO_DEVICE);
1597 if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1598 dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1599 dma_release_channel(chan);
1600 } else {
1601 dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1602 __func__, UART_XMIT_SIZE,
1603 port->state->xmit.buf, &s->tx_dma_addr);
1604
1605 INIT_WORK(&s->work_tx, sci_dma_tx_work_fn);
1606 s->chan_tx_saved = s->chan_tx = chan;
1607 }
1608 }
1609
1610 chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1611 dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1612 if (chan) {
1613 unsigned int i;
1614 dma_addr_t dma;
1615 void *buf;
1616
1617 s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1618 buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1619 &dma, GFP_KERNEL);
1620 if (!buf) {
1621 dev_warn(port->dev,
1622 "Failed to allocate Rx dma buffer, using PIO\n");
1623 dma_release_channel(chan);
1624 return;
1625 }
1626
1627 for (i = 0; i < 2; i++) {
1628 struct scatterlist *sg = &s->sg_rx[i];
1629
1630 sg_init_table(sg, 1);
1631 s->rx_buf[i] = buf;
1632 sg_dma_address(sg) = dma;
1633 sg_dma_len(sg) = s->buf_len_rx;
1634
1635 buf += s->buf_len_rx;
1636 dma += s->buf_len_rx;
1637 }
1638
1639 hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1640 s->rx_timer.function = sci_dma_rx_timer_fn;
1641
1642 s->chan_rx_saved = s->chan_rx = chan;
1643
1644 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1645 sci_dma_rx_submit(s, false);
1646 }
1647 }
1648
1649 static void sci_free_dma(struct uart_port *port)
1650 {
1651 struct sci_port *s = to_sci_port(port);
1652
1653 if (s->chan_tx_saved)
1654 sci_dma_tx_release(s);
1655 if (s->chan_rx_saved)
1656 sci_dma_rx_release(s);
1657 }
1658
1659 static void sci_flush_buffer(struct uart_port *port)
1660 {
1661 struct sci_port *s = to_sci_port(port);
1662
1663 /*
1664 * In uart_flush_buffer(), the xmit circular buffer has just been
1665 * cleared, so we have to reset tx_dma_len accordingly, and stop any
1666 * pending transfers
1667 */
1668 s->tx_dma_len = 0;
1669 if (s->chan_tx) {
1670 dmaengine_terminate_async(s->chan_tx);
1671 s->cookie_tx = -EINVAL;
1672 }
1673 }
1674 #else /* !CONFIG_SERIAL_SH_SCI_DMA */
1675 static inline void sci_request_dma(struct uart_port *port)
1676 {
1677 }
1678
1679 static inline void sci_free_dma(struct uart_port *port)
1680 {
1681 }
1682
1683 #define sci_flush_buffer NULL
1684 #endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1685
1686 static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1687 {
1688 struct uart_port *port = ptr;
1689 struct sci_port *s = to_sci_port(port);
1690
1691 #ifdef CONFIG_SERIAL_SH_SCI_DMA
1692 if (s->chan_rx) {
1693 u16 scr = serial_port_in(port, SCSCR);
1694 u16 ssr = serial_port_in(port, SCxSR);
1695
1696 /* Disable future Rx interrupts */
1697 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1698 disable_irq_nosync(irq);
1699 scr |= SCSCR_RDRQE;
1700 } else {
1701 if (sci_dma_rx_submit(s, false) < 0)
1702 goto handle_pio;
1703
1704 scr &= ~SCSCR_RIE;
1705 }
1706 serial_port_out(port, SCSCR, scr);
1707 /* Clear current interrupt */
1708 serial_port_out(port, SCxSR,
1709 ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1710 dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1711 jiffies, s->rx_timeout);
1712 start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1713
1714 return IRQ_HANDLED;
1715 }
1716
1717 handle_pio:
1718 #endif
1719
1720 if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1721 if (!scif_rtrg_enabled(port))
1722 scif_set_rtrg(port, s->rx_trigger);
1723
1724 mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1725 s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1726 }
1727
1728 /* I think sci_receive_chars has to be called irrespective
1729 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1730 * to be disabled?
1731 */
1732 sci_receive_chars(port);
1733
1734 return IRQ_HANDLED;
1735 }
1736
1737 static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1738 {
1739 struct uart_port *port = ptr;
1740 unsigned long flags;
1741
1742 spin_lock_irqsave(&port->lock, flags);
1743 sci_transmit_chars(port);
1744 spin_unlock_irqrestore(&port->lock, flags);
1745
1746 return IRQ_HANDLED;
1747 }
1748
1749 static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1750 {
1751 struct uart_port *port = ptr;
1752
1753 /* Handle BREAKs */
1754 sci_handle_breaks(port);
1755 sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1756
1757 return IRQ_HANDLED;
1758 }
1759
1760 static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1761 {
1762 struct uart_port *port = ptr;
1763 struct sci_port *s = to_sci_port(port);
1764
1765 if (s->irqs[SCIx_ERI_IRQ] == s->irqs[SCIx_BRI_IRQ]) {
1766 /* Break and Error interrupts are muxed */
1767 unsigned short ssr_status = serial_port_in(port, SCxSR);
1768
1769 /* Break Interrupt */
1770 if (ssr_status & SCxSR_BRK(port))
1771 sci_br_interrupt(irq, ptr);
1772
1773 /* Break only? */
1774 if (!(ssr_status & SCxSR_ERRORS(port)))
1775 return IRQ_HANDLED;
1776 }
1777
1778 /* Handle errors */
1779 if (port->type == PORT_SCI) {
1780 if (sci_handle_errors(port)) {
1781 /* discard character in rx buffer */
1782 serial_port_in(port, SCxSR);
1783 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1784 }
1785 } else {
1786 sci_handle_fifo_overrun(port);
1787 if (!s->chan_rx)
1788 sci_receive_chars(port);
1789 }
1790
1791 sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1792
1793 /* Kick the transmission */
1794 if (!s->chan_tx)
1795 sci_tx_interrupt(irq, ptr);
1796
1797 return IRQ_HANDLED;
1798 }
1799
1800 static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1801 {
1802 unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1803 struct uart_port *port = ptr;
1804 struct sci_port *s = to_sci_port(port);
1805 irqreturn_t ret = IRQ_NONE;
1806
1807 ssr_status = serial_port_in(port, SCxSR);
1808 scr_status = serial_port_in(port, SCSCR);
1809 if (s->params->overrun_reg == SCxSR)
1810 orer_status = ssr_status;
1811 else if (sci_getreg(port, s->params->overrun_reg)->size)
1812 orer_status = serial_port_in(port, s->params->overrun_reg);
1813
1814 err_enabled = scr_status & port_rx_irq_mask(port);
1815
1816 /* Tx Interrupt */
1817 if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1818 !s->chan_tx)
1819 ret = sci_tx_interrupt(irq, ptr);
1820
1821 /*
1822 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1823 * DR flags
1824 */
1825 if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1826 (scr_status & SCSCR_RIE))
1827 ret = sci_rx_interrupt(irq, ptr);
1828
1829 /* Error Interrupt */
1830 if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1831 ret = sci_er_interrupt(irq, ptr);
1832
1833 /* Break Interrupt */
1834 if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1835 ret = sci_br_interrupt(irq, ptr);
1836
1837 /* Overrun Interrupt */
1838 if (orer_status & s->params->overrun_mask) {
1839 sci_handle_fifo_overrun(port);
1840 ret = IRQ_HANDLED;
1841 }
1842
1843 return ret;
1844 }
1845
1846 static const struct sci_irq_desc {
1847 const char *desc;
1848 irq_handler_t handler;
1849 } sci_irq_desc[] = {
1850 /*
1851 * Split out handlers, the default case.
1852 */
1853 [SCIx_ERI_IRQ] = {
1854 .desc = "rx err",
1855 .handler = sci_er_interrupt,
1856 },
1857
1858 [SCIx_RXI_IRQ] = {
1859 .desc = "rx full",
1860 .handler = sci_rx_interrupt,
1861 },
1862
1863 [SCIx_TXI_IRQ] = {
1864 .desc = "tx empty",
1865 .handler = sci_tx_interrupt,
1866 },
1867
1868 [SCIx_BRI_IRQ] = {
1869 .desc = "break",
1870 .handler = sci_br_interrupt,
1871 },
1872
1873 [SCIx_DRI_IRQ] = {
1874 .desc = "rx ready",
1875 .handler = sci_rx_interrupt,
1876 },
1877
1878 [SCIx_TEI_IRQ] = {
1879 .desc = "tx end",
1880 .handler = sci_tx_interrupt,
1881 },
1882
1883 /*
1884 * Special muxed handler.
1885 */
1886 [SCIx_MUX_IRQ] = {
1887 .desc = "mux",
1888 .handler = sci_mpxed_interrupt,
1889 },
1890 };
1891
1892 static int sci_request_irq(struct sci_port *port)
1893 {
1894 struct uart_port *up = &port->port;
1895 int i, j, w, ret = 0;
1896
1897 for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1898 const struct sci_irq_desc *desc;
1899 int irq;
1900
1901 /* Check if already registered (muxed) */
1902 for (w = 0; w < i; w++)
1903 if (port->irqs[w] == port->irqs[i])
1904 w = i + 1;
1905 if (w > i)
1906 continue;
1907
1908 if (SCIx_IRQ_IS_MUXED(port)) {
1909 i = SCIx_MUX_IRQ;
1910 irq = up->irq;
1911 } else {
1912 irq = port->irqs[i];
1913
1914 /*
1915 * Certain port types won't support all of the
1916 * available interrupt sources.
1917 */
1918 if (unlikely(irq < 0))
1919 continue;
1920 }
1921
1922 desc = sci_irq_desc + i;
1923 port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1924 dev_name(up->dev), desc->desc);
1925 if (!port->irqstr[j]) {
1926 ret = -ENOMEM;
1927 goto out_nomem;
1928 }
1929
1930 ret = request_irq(irq, desc->handler, up->irqflags,
1931 port->irqstr[j], port);
1932 if (unlikely(ret)) {
1933 dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1934 goto out_noirq;
1935 }
1936 }
1937
1938 return 0;
1939
1940 out_noirq:
1941 while (--i >= 0)
1942 free_irq(port->irqs[i], port);
1943
1944 out_nomem:
1945 while (--j >= 0)
1946 kfree(port->irqstr[j]);
1947
1948 return ret;
1949 }
1950
1951 static void sci_free_irq(struct sci_port *port)
1952 {
1953 int i, j;
1954
1955 /*
1956 * Intentionally in reverse order so we iterate over the muxed
1957 * IRQ first.
1958 */
1959 for (i = 0; i < SCIx_NR_IRQS; i++) {
1960 int irq = port->irqs[i];
1961
1962 /*
1963 * Certain port types won't support all of the available
1964 * interrupt sources.
1965 */
1966 if (unlikely(irq < 0))
1967 continue;
1968
1969 /* Check if already freed (irq was muxed) */
1970 for (j = 0; j < i; j++)
1971 if (port->irqs[j] == irq)
1972 j = i + 1;
1973 if (j > i)
1974 continue;
1975
1976 free_irq(port->irqs[i], port);
1977 kfree(port->irqstr[i]);
1978
1979 if (SCIx_IRQ_IS_MUXED(port)) {
1980 /* If there's only one IRQ, we're done. */
1981 return;
1982 }
1983 }
1984 }
1985
1986 static unsigned int sci_tx_empty(struct uart_port *port)
1987 {
1988 unsigned short status = serial_port_in(port, SCxSR);
1989 unsigned short in_tx_fifo = sci_txfill(port);
1990
1991 return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1992 }
1993
1994 static void sci_set_rts(struct uart_port *port, bool state)
1995 {
1996 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1997 u16 data = serial_port_in(port, SCPDR);
1998
1999 /* Active low */
2000 if (state)
2001 data &= ~SCPDR_RTSD;
2002 else
2003 data |= SCPDR_RTSD;
2004 serial_port_out(port, SCPDR, data);
2005
2006 /* RTS# is output */
2007 serial_port_out(port, SCPCR,
2008 serial_port_in(port, SCPCR) | SCPCR_RTSC);
2009 } else if (sci_getreg(port, SCSPTR)->size) {
2010 u16 ctrl = serial_port_in(port, SCSPTR);
2011
2012 /* Active low */
2013 if (state)
2014 ctrl &= ~SCSPTR_RTSDT;
2015 else
2016 ctrl |= SCSPTR_RTSDT;
2017 serial_port_out(port, SCSPTR, ctrl);
2018 }
2019 }
2020
2021 static bool sci_get_cts(struct uart_port *port)
2022 {
2023 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2024 /* Active low */
2025 return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
2026 } else if (sci_getreg(port, SCSPTR)->size) {
2027 /* Active low */
2028 return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
2029 }
2030
2031 return true;
2032 }
2033
2034 /*
2035 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
2036 * CTS/RTS is supported in hardware by at least one port and controlled
2037 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
2038 * handled via the ->init_pins() op, which is a bit of a one-way street,
2039 * lacking any ability to defer pin control -- this will later be
2040 * converted over to the GPIO framework).
2041 *
2042 * Other modes (such as loopback) are supported generically on certain
2043 * port types, but not others. For these it's sufficient to test for the
2044 * existence of the support register and simply ignore the port type.
2045 */
2046 static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
2047 {
2048 struct sci_port *s = to_sci_port(port);
2049
2050 if (mctrl & TIOCM_LOOP) {
2051 const struct plat_sci_reg *reg;
2052
2053 /*
2054 * Standard loopback mode for SCFCR ports.
2055 */
2056 reg = sci_getreg(port, SCFCR);
2057 if (reg->size)
2058 serial_port_out(port, SCFCR,
2059 serial_port_in(port, SCFCR) |
2060 SCFCR_LOOP);
2061 }
2062
2063 mctrl_gpio_set(s->gpios, mctrl);
2064
2065 if (!s->has_rtscts)
2066 return;
2067
2068 if (!(mctrl & TIOCM_RTS)) {
2069 /* Disable Auto RTS */
2070 serial_port_out(port, SCFCR,
2071 serial_port_in(port, SCFCR) & ~SCFCR_MCE);
2072
2073 /* Clear RTS */
2074 sci_set_rts(port, 0);
2075 } else if (s->autorts) {
2076 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
2077 /* Enable RTS# pin function */
2078 serial_port_out(port, SCPCR,
2079 serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
2080 }
2081
2082 /* Enable Auto RTS */
2083 serial_port_out(port, SCFCR,
2084 serial_port_in(port, SCFCR) | SCFCR_MCE);
2085 } else {
2086 /* Set RTS */
2087 sci_set_rts(port, 1);
2088 }
2089 }
2090
2091 static unsigned int sci_get_mctrl(struct uart_port *port)
2092 {
2093 struct sci_port *s = to_sci_port(port);
2094 struct mctrl_gpios *gpios = s->gpios;
2095 unsigned int mctrl = 0;
2096
2097 mctrl_gpio_get(gpios, &mctrl);
2098
2099 /*
2100 * CTS/RTS is handled in hardware when supported, while nothing
2101 * else is wired up.
2102 */
2103 if (s->autorts) {
2104 if (sci_get_cts(port))
2105 mctrl |= TIOCM_CTS;
2106 } else if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS)) {
2107 mctrl |= TIOCM_CTS;
2108 }
2109 if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR))
2110 mctrl |= TIOCM_DSR;
2111 if (!mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD))
2112 mctrl |= TIOCM_CAR;
2113
2114 return mctrl;
2115 }
2116
2117 static void sci_enable_ms(struct uart_port *port)
2118 {
2119 mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2120 }
2121
2122 static void sci_break_ctl(struct uart_port *port, int break_state)
2123 {
2124 unsigned short scscr, scsptr;
2125 unsigned long flags;
2126
2127 /* check wheter the port has SCSPTR */
2128 if (!sci_getreg(port, SCSPTR)->size) {
2129 /*
2130 * Not supported by hardware. Most parts couple break and rx
2131 * interrupts together, with break detection always enabled.
2132 */
2133 return;
2134 }
2135
2136 spin_lock_irqsave(&port->lock, flags);
2137 scsptr = serial_port_in(port, SCSPTR);
2138 scscr = serial_port_in(port, SCSCR);
2139
2140 if (break_state == -1) {
2141 scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2142 scscr &= ~SCSCR_TE;
2143 } else {
2144 scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2145 scscr |= SCSCR_TE;
2146 }
2147
2148 serial_port_out(port, SCSPTR, scsptr);
2149 serial_port_out(port, SCSCR, scscr);
2150 spin_unlock_irqrestore(&port->lock, flags);
2151 }
2152
2153 static int sci_startup(struct uart_port *port)
2154 {
2155 struct sci_port *s = to_sci_port(port);
2156 int ret;
2157
2158 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2159
2160 sci_request_dma(port);
2161
2162 ret = sci_request_irq(s);
2163 if (unlikely(ret < 0)) {
2164 sci_free_dma(port);
2165 return ret;
2166 }
2167
2168 return 0;
2169 }
2170
2171 static void sci_shutdown(struct uart_port *port)
2172 {
2173 struct sci_port *s = to_sci_port(port);
2174 unsigned long flags;
2175 u16 scr;
2176
2177 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2178
2179 s->autorts = false;
2180 mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2181
2182 spin_lock_irqsave(&port->lock, flags);
2183 sci_stop_rx(port);
2184 sci_stop_tx(port);
2185 /*
2186 * Stop RX and TX, disable related interrupts, keep clock source
2187 * and HSCIF TOT bits
2188 */
2189 scr = serial_port_in(port, SCSCR);
2190 serial_port_out(port, SCSCR, scr &
2191 (SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2192 spin_unlock_irqrestore(&port->lock, flags);
2193
2194 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2195 if (s->chan_rx_saved) {
2196 dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2197 port->line);
2198 hrtimer_cancel(&s->rx_timer);
2199 }
2200 #endif
2201
2202 if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0)
2203 del_timer_sync(&s->rx_fifo_timer);
2204 sci_free_irq(s);
2205 sci_free_dma(port);
2206 }
2207
2208 static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2209 unsigned int *srr)
2210 {
2211 unsigned long freq = s->clk_rates[SCI_SCK];
2212 int err, min_err = INT_MAX;
2213 unsigned int sr;
2214
2215 if (s->port.type != PORT_HSCIF)
2216 freq *= 2;
2217
2218 for_each_sr(sr, s) {
2219 err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2220 if (abs(err) >= abs(min_err))
2221 continue;
2222
2223 min_err = err;
2224 *srr = sr - 1;
2225
2226 if (!err)
2227 break;
2228 }
2229
2230 dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2231 *srr + 1);
2232 return min_err;
2233 }
2234
2235 static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2236 unsigned long freq, unsigned int *dlr,
2237 unsigned int *srr)
2238 {
2239 int err, min_err = INT_MAX;
2240 unsigned int sr, dl;
2241
2242 if (s->port.type != PORT_HSCIF)
2243 freq *= 2;
2244
2245 for_each_sr(sr, s) {
2246 dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2247 dl = clamp(dl, 1U, 65535U);
2248
2249 err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2250 if (abs(err) >= abs(min_err))
2251 continue;
2252
2253 min_err = err;
2254 *dlr = dl;
2255 *srr = sr - 1;
2256
2257 if (!err)
2258 break;
2259 }
2260
2261 dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2262 min_err, *dlr, *srr + 1);
2263 return min_err;
2264 }
2265
2266 /* calculate sample rate, BRR, and clock select */
2267 static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2268 unsigned int *brr, unsigned int *srr,
2269 unsigned int *cks)
2270 {
2271 unsigned long freq = s->clk_rates[SCI_FCK];
2272 unsigned int sr, br, prediv, scrate, c;
2273 int err, min_err = INT_MAX;
2274
2275 if (s->port.type != PORT_HSCIF)
2276 freq *= 2;
2277
2278 /*
2279 * Find the combination of sample rate and clock select with the
2280 * smallest deviation from the desired baud rate.
2281 * Prefer high sample rates to maximise the receive margin.
2282 *
2283 * M: Receive margin (%)
2284 * N: Ratio of bit rate to clock (N = sampling rate)
2285 * D: Clock duty (D = 0 to 1.0)
2286 * L: Frame length (L = 9 to 12)
2287 * F: Absolute value of clock frequency deviation
2288 *
2289 * M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2290 * (|D - 0.5| / N * (1 + F))|
2291 * NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2292 */
2293 for_each_sr(sr, s) {
2294 for (c = 0; c <= 3; c++) {
2295 /* integerized formulas from HSCIF documentation */
2296 prediv = sr * (1 << (2 * c + 1));
2297
2298 /*
2299 * We need to calculate:
2300 *
2301 * br = freq / (prediv * bps) clamped to [1..256]
2302 * err = freq / (br * prediv) - bps
2303 *
2304 * Watch out for overflow when calculating the desired
2305 * sampling clock rate!
2306 */
2307 if (bps > UINT_MAX / prediv)
2308 break;
2309
2310 scrate = prediv * bps;
2311 br = DIV_ROUND_CLOSEST(freq, scrate);
2312 br = clamp(br, 1U, 256U);
2313
2314 err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2315 if (abs(err) >= abs(min_err))
2316 continue;
2317
2318 min_err = err;
2319 *brr = br - 1;
2320 *srr = sr - 1;
2321 *cks = c;
2322
2323 if (!err)
2324 goto found;
2325 }
2326 }
2327
2328 found:
2329 dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2330 min_err, *brr, *srr + 1, *cks);
2331 return min_err;
2332 }
2333
2334 static void sci_reset(struct uart_port *port)
2335 {
2336 const struct plat_sci_reg *reg;
2337 unsigned int status;
2338 struct sci_port *s = to_sci_port(port);
2339
2340 serial_port_out(port, SCSCR, s->hscif_tot); /* TE=0, RE=0, CKE1=0 */
2341
2342 reg = sci_getreg(port, SCFCR);
2343 if (reg->size)
2344 serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2345
2346 sci_clear_SCxSR(port,
2347 SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2348 SCxSR_BREAK_CLEAR(port));
2349 if (sci_getreg(port, SCLSR)->size) {
2350 status = serial_port_in(port, SCLSR);
2351 status &= ~(SCLSR_TO | SCLSR_ORER);
2352 serial_port_out(port, SCLSR, status);
2353 }
2354
2355 if (s->rx_trigger > 1) {
2356 if (s->rx_fifo_timeout) {
2357 scif_set_rtrg(port, 1);
2358 timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2359 } else {
2360 if (port->type == PORT_SCIFA ||
2361 port->type == PORT_SCIFB)
2362 scif_set_rtrg(port, 1);
2363 else
2364 scif_set_rtrg(port, s->rx_trigger);
2365 }
2366 }
2367 }
2368
2369 static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2370 struct ktermios *old)
2371 {
2372 unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2373 unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2374 unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2375 struct sci_port *s = to_sci_port(port);
2376 const struct plat_sci_reg *reg;
2377 int min_err = INT_MAX, err;
2378 unsigned long max_freq = 0;
2379 int best_clk = -1;
2380 unsigned long flags;
2381
2382 if ((termios->c_cflag & CSIZE) == CS7)
2383 smr_val |= SCSMR_CHR;
2384 if (termios->c_cflag & PARENB)
2385 smr_val |= SCSMR_PE;
2386 if (termios->c_cflag & PARODD)
2387 smr_val |= SCSMR_PE | SCSMR_ODD;
2388 if (termios->c_cflag & CSTOPB)
2389 smr_val |= SCSMR_STOP;
2390
2391 /*
2392 * earlyprintk comes here early on with port->uartclk set to zero.
2393 * the clock framework is not up and running at this point so here
2394 * we assume that 115200 is the maximum baud rate. please note that
2395 * the baud rate is not programmed during earlyprintk - it is assumed
2396 * that the previous boot loader has enabled required clocks and
2397 * setup the baud rate generator hardware for us already.
2398 */
2399 if (!port->uartclk) {
2400 baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2401 goto done;
2402 }
2403
2404 for (i = 0; i < SCI_NUM_CLKS; i++)
2405 max_freq = max(max_freq, s->clk_rates[i]);
2406
2407 baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2408 if (!baud)
2409 goto done;
2410
2411 /*
2412 * There can be multiple sources for the sampling clock. Find the one
2413 * that gives us the smallest deviation from the desired baud rate.
2414 */
2415
2416 /* Optional Undivided External Clock */
2417 if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2418 port->type != PORT_SCIFB) {
2419 err = sci_sck_calc(s, baud, &srr1);
2420 if (abs(err) < abs(min_err)) {
2421 best_clk = SCI_SCK;
2422 scr_val = SCSCR_CKE1;
2423 sccks = SCCKS_CKS;
2424 min_err = err;
2425 srr = srr1;
2426 if (!err)
2427 goto done;
2428 }
2429 }
2430
2431 /* Optional BRG Frequency Divided External Clock */
2432 if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2433 err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2434 &srr1);
2435 if (abs(err) < abs(min_err)) {
2436 best_clk = SCI_SCIF_CLK;
2437 scr_val = SCSCR_CKE1;
2438 sccks = 0;
2439 min_err = err;
2440 dl = dl1;
2441 srr = srr1;
2442 if (!err)
2443 goto done;
2444 }
2445 }
2446
2447 /* Optional BRG Frequency Divided Internal Clock */
2448 if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2449 err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2450 &srr1);
2451 if (abs(err) < abs(min_err)) {
2452 best_clk = SCI_BRG_INT;
2453 scr_val = SCSCR_CKE1;
2454 sccks = SCCKS_XIN;
2455 min_err = err;
2456 dl = dl1;
2457 srr = srr1;
2458 if (!min_err)
2459 goto done;
2460 }
2461 }
2462
2463 /* Divided Functional Clock using standard Bit Rate Register */
2464 err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2465 if (abs(err) < abs(min_err)) {
2466 best_clk = SCI_FCK;
2467 scr_val = 0;
2468 min_err = err;
2469 brr = brr1;
2470 srr = srr1;
2471 cks = cks1;
2472 }
2473
2474 done:
2475 if (best_clk >= 0)
2476 dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2477 s->clks[best_clk], baud, min_err);
2478
2479 sci_port_enable(s);
2480
2481 /*
2482 * Program the optional External Baud Rate Generator (BRG) first.
2483 * It controls the mux to select (H)SCK or frequency divided clock.
2484 */
2485 if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2486 serial_port_out(port, SCDL, dl);
2487 serial_port_out(port, SCCKS, sccks);
2488 }
2489
2490 spin_lock_irqsave(&port->lock, flags);
2491
2492 sci_reset(port);
2493
2494 uart_update_timeout(port, termios->c_cflag, baud);
2495
2496 /* byte size and parity */
2497 switch (termios->c_cflag & CSIZE) {
2498 case CS5:
2499 bits = 7;
2500 break;
2501 case CS6:
2502 bits = 8;
2503 break;
2504 case CS7:
2505 bits = 9;
2506 break;
2507 default:
2508 bits = 10;
2509 break;
2510 }
2511
2512 if (termios->c_cflag & CSTOPB)
2513 bits++;
2514 if (termios->c_cflag & PARENB)
2515 bits++;
2516
2517 if (best_clk >= 0) {
2518 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2519 switch (srr + 1) {
2520 case 5: smr_val |= SCSMR_SRC_5; break;
2521 case 7: smr_val |= SCSMR_SRC_7; break;
2522 case 11: smr_val |= SCSMR_SRC_11; break;
2523 case 13: smr_val |= SCSMR_SRC_13; break;
2524 case 16: smr_val |= SCSMR_SRC_16; break;
2525 case 17: smr_val |= SCSMR_SRC_17; break;
2526 case 19: smr_val |= SCSMR_SRC_19; break;
2527 case 27: smr_val |= SCSMR_SRC_27; break;
2528 }
2529 smr_val |= cks;
2530 serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2531 serial_port_out(port, SCSMR, smr_val);
2532 serial_port_out(port, SCBRR, brr);
2533 if (sci_getreg(port, HSSRR)->size) {
2534 unsigned int hssrr = srr | HSCIF_SRE;
2535 /* Calculate deviation from intended rate at the
2536 * center of the last stop bit in sampling clocks.
2537 */
2538 int last_stop = bits * 2 - 1;
2539 int deviation = DIV_ROUND_CLOSEST(min_err * last_stop *
2540 (int)(srr + 1),
2541 2 * (int)baud);
2542
2543 if (abs(deviation) >= 2) {
2544 /* At least two sampling clocks off at the
2545 * last stop bit; we can increase the error
2546 * margin by shifting the sampling point.
2547 */
2548 int shift = clamp(deviation / 2, -8, 7);
2549
2550 hssrr |= (shift << HSCIF_SRHP_SHIFT) &
2551 HSCIF_SRHP_MASK;
2552 hssrr |= HSCIF_SRDE;
2553 }
2554 serial_port_out(port, HSSRR, hssrr);
2555 }
2556
2557 /* Wait one bit interval */
2558 udelay((1000000 + (baud - 1)) / baud);
2559 } else {
2560 /* Don't touch the bit rate configuration */
2561 scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2562 smr_val |= serial_port_in(port, SCSMR) &
2563 (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2564 serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2565 serial_port_out(port, SCSMR, smr_val);
2566 }
2567
2568 sci_init_pins(port, termios->c_cflag);
2569
2570 port->status &= ~UPSTAT_AUTOCTS;
2571 s->autorts = false;
2572 reg = sci_getreg(port, SCFCR);
2573 if (reg->size) {
2574 unsigned short ctrl = serial_port_in(port, SCFCR);
2575
2576 if ((port->flags & UPF_HARD_FLOW) &&
2577 (termios->c_cflag & CRTSCTS)) {
2578 /* There is no CTS interrupt to restart the hardware */
2579 port->status |= UPSTAT_AUTOCTS;
2580 /* MCE is enabled when RTS is raised */
2581 s->autorts = true;
2582 }
2583
2584 /*
2585 * As we've done a sci_reset() above, ensure we don't
2586 * interfere with the FIFOs while toggling MCE. As the
2587 * reset values could still be set, simply mask them out.
2588 */
2589 ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2590
2591 serial_port_out(port, SCFCR, ctrl);
2592 }
2593 if (port->flags & UPF_HARD_FLOW) {
2594 /* Refresh (Auto) RTS */
2595 sci_set_mctrl(port, port->mctrl);
2596 }
2597
2598 scr_val |= SCSCR_RE | SCSCR_TE |
2599 (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2600 serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2601 if ((srr + 1 == 5) &&
2602 (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2603 /*
2604 * In asynchronous mode, when the sampling rate is 1/5, first
2605 * received data may become invalid on some SCIFA and SCIFB.
2606 * To avoid this problem wait more than 1 serial data time (1
2607 * bit time x serial data number) after setting SCSCR.RE = 1.
2608 */
2609 udelay(DIV_ROUND_UP(10 * 1000000, baud));
2610 }
2611
2612 /*
2613 * Calculate delay for 2 DMA buffers (4 FIFO).
2614 * See serial_core.c::uart_update_timeout().
2615 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2616 * function calculates 1 jiffie for the data plus 5 jiffies for the
2617 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2618 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2619 * value obtained by this formula is too small. Therefore, if the value
2620 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2621 */
2622 s->rx_frame = (10000 * bits) / (baud / 100);
2623 #ifdef CONFIG_SERIAL_SH_SCI_DMA
2624 s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2625 if (s->rx_timeout < 20)
2626 s->rx_timeout = 20;
2627 #endif
2628
2629 if ((termios->c_cflag & CREAD) != 0)
2630 sci_start_rx(port);
2631
2632 spin_unlock_irqrestore(&port->lock, flags);
2633
2634 sci_port_disable(s);
2635
2636 if (UART_ENABLE_MS(port, termios->c_cflag))
2637 sci_enable_ms(port);
2638 }
2639
2640 static void sci_pm(struct uart_port *port, unsigned int state,
2641 unsigned int oldstate)
2642 {
2643 struct sci_port *sci_port = to_sci_port(port);
2644
2645 switch (state) {
2646 case UART_PM_STATE_OFF:
2647 sci_port_disable(sci_port);
2648 break;
2649 default:
2650 sci_port_enable(sci_port);
2651 break;
2652 }
2653 }
2654
2655 static const char *sci_type(struct uart_port *port)
2656 {
2657 switch (port->type) {
2658 case PORT_IRDA:
2659 return "irda";
2660 case PORT_SCI:
2661 return "sci";
2662 case PORT_SCIF:
2663 return "scif";
2664 case PORT_SCIFA:
2665 return "scifa";
2666 case PORT_SCIFB:
2667 return "scifb";
2668 case PORT_HSCIF:
2669 return "hscif";
2670 }
2671
2672 return NULL;
2673 }
2674
2675 static int sci_remap_port(struct uart_port *port)
2676 {
2677 struct sci_port *sport = to_sci_port(port);
2678
2679 /*
2680 * Nothing to do if there's already an established membase.
2681 */
2682 if (port->membase)
2683 return 0;
2684
2685 if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2686 port->membase = ioremap(port->mapbase, sport->reg_size);
2687 if (unlikely(!port->membase)) {
2688 dev_err(port->dev, "can't remap port#%d\n", port->line);
2689 return -ENXIO;
2690 }
2691 } else {
2692 /*
2693 * For the simple (and majority of) cases where we don't
2694 * need to do any remapping, just cast the cookie
2695 * directly.
2696 */
2697 port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2698 }
2699
2700 return 0;
2701 }
2702
2703 static void sci_release_port(struct uart_port *port)
2704 {
2705 struct sci_port *sport = to_sci_port(port);
2706
2707 if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2708 iounmap(port->membase);
2709 port->membase = NULL;
2710 }
2711
2712 release_mem_region(port->mapbase, sport->reg_size);
2713 }
2714
2715 static int sci_request_port(struct uart_port *port)
2716 {
2717 struct resource *res;
2718 struct sci_port *sport = to_sci_port(port);
2719 int ret;
2720
2721 res = request_mem_region(port->mapbase, sport->reg_size,
2722 dev_name(port->dev));
2723 if (unlikely(res == NULL)) {
2724 dev_err(port->dev, "request_mem_region failed.");
2725 return -EBUSY;
2726 }
2727
2728 ret = sci_remap_port(port);
2729 if (unlikely(ret != 0)) {
2730 release_resource(res);
2731 return ret;
2732 }
2733
2734 return 0;
2735 }
2736
2737 static void sci_config_port(struct uart_port *port, int flags)
2738 {
2739 if (flags & UART_CONFIG_TYPE) {
2740 struct sci_port *sport = to_sci_port(port);
2741
2742 port->type = sport->cfg->type;
2743 sci_request_port(port);
2744 }
2745 }
2746
2747 static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2748 {
2749 if (ser->baud_base < 2400)
2750 /* No paper tape reader for Mitch.. */
2751 return -EINVAL;
2752
2753 return 0;
2754 }
2755
2756 static const struct uart_ops sci_uart_ops = {
2757 .tx_empty = sci_tx_empty,
2758 .set_mctrl = sci_set_mctrl,
2759 .get_mctrl = sci_get_mctrl,
2760 .start_tx = sci_start_tx,
2761 .stop_tx = sci_stop_tx,
2762 .stop_rx = sci_stop_rx,
2763 .enable_ms = sci_enable_ms,
2764 .break_ctl = sci_break_ctl,
2765 .startup = sci_startup,
2766 .shutdown = sci_shutdown,
2767 .flush_buffer = sci_flush_buffer,
2768 .set_termios = sci_set_termios,
2769 .pm = sci_pm,
2770 .type = sci_type,
2771 .release_port = sci_release_port,
2772 .request_port = sci_request_port,
2773 .config_port = sci_config_port,
2774 .verify_port = sci_verify_port,
2775 #ifdef CONFIG_CONSOLE_POLL
2776 .poll_get_char = sci_poll_get_char,
2777 .poll_put_char = sci_poll_put_char,
2778 #endif
2779 };
2780
2781 static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2782 {
2783 const char *clk_names[] = {
2784 [SCI_FCK] = "fck",
2785 [SCI_SCK] = "sck",
2786 [SCI_BRG_INT] = "brg_int",
2787 [SCI_SCIF_CLK] = "scif_clk",
2788 };
2789 struct clk *clk;
2790 unsigned int i;
2791
2792 if (sci_port->cfg->type == PORT_HSCIF)
2793 clk_names[SCI_SCK] = "hsck";
2794
2795 for (i = 0; i < SCI_NUM_CLKS; i++) {
2796 clk = devm_clk_get(dev, clk_names[i]);
2797 if (PTR_ERR(clk) == -EPROBE_DEFER)
2798 return -EPROBE_DEFER;
2799
2800 if (IS_ERR(clk) && i == SCI_FCK) {
2801 /*
2802 * "fck" used to be called "sci_ick", and we need to
2803 * maintain DT backward compatibility.
2804 */
2805 clk = devm_clk_get(dev, "sci_ick");
2806 if (PTR_ERR(clk) == -EPROBE_DEFER)
2807 return -EPROBE_DEFER;
2808
2809 if (!IS_ERR(clk))
2810 goto found;
2811
2812 /*
2813 * Not all SH platforms declare a clock lookup entry
2814 * for SCI devices, in which case we need to get the
2815 * global "peripheral_clk" clock.
2816 */
2817 clk = devm_clk_get(dev, "peripheral_clk");
2818 if (!IS_ERR(clk))
2819 goto found;
2820
2821 dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2822 PTR_ERR(clk));
2823 return PTR_ERR(clk);
2824 }
2825
2826 found:
2827 if (IS_ERR(clk))
2828 dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2829 PTR_ERR(clk));
2830 else
2831 dev_dbg(dev, "clk %s is %pC rate %lu\n", clk_names[i],
2832 clk, clk_get_rate(clk));
2833 sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2834 }
2835 return 0;
2836 }
2837
2838 static const struct sci_port_params *
2839 sci_probe_regmap(const struct plat_sci_port *cfg)
2840 {
2841 unsigned int regtype;
2842
2843 if (cfg->regtype != SCIx_PROBE_REGTYPE)
2844 return &sci_port_params[cfg->regtype];
2845
2846 switch (cfg->type) {
2847 case PORT_SCI:
2848 regtype = SCIx_SCI_REGTYPE;
2849 break;
2850 case PORT_IRDA:
2851 regtype = SCIx_IRDA_REGTYPE;
2852 break;
2853 case PORT_SCIFA:
2854 regtype = SCIx_SCIFA_REGTYPE;
2855 break;
2856 case PORT_SCIFB:
2857 regtype = SCIx_SCIFB_REGTYPE;
2858 break;
2859 case PORT_SCIF:
2860 /*
2861 * The SH-4 is a bit of a misnomer here, although that's
2862 * where this particular port layout originated. This
2863 * configuration (or some slight variation thereof)
2864 * remains the dominant model for all SCIFs.
2865 */
2866 regtype = SCIx_SH4_SCIF_REGTYPE;
2867 break;
2868 case PORT_HSCIF:
2869 regtype = SCIx_HSCIF_REGTYPE;
2870 break;
2871 default:
2872 pr_err("Can't probe register map for given port\n");
2873 return NULL;
2874 }
2875
2876 return &sci_port_params[regtype];
2877 }
2878
2879 static int sci_init_single(struct platform_device *dev,
2880 struct sci_port *sci_port, unsigned int index,
2881 const struct plat_sci_port *p, bool early)
2882 {
2883 struct uart_port *port = &sci_port->port;
2884 const struct resource *res;
2885 unsigned int i;
2886 int ret;
2887
2888 sci_port->cfg = p;
2889
2890 port->ops = &sci_uart_ops;
2891 port->iotype = UPIO_MEM;
2892 port->line = index;
2893 port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_SH_SCI_CONSOLE);
2894
2895 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2896 if (res == NULL)
2897 return -ENOMEM;
2898
2899 port->mapbase = res->start;
2900 sci_port->reg_size = resource_size(res);
2901
2902 for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) {
2903 if (i)
2904 sci_port->irqs[i] = platform_get_irq_optional(dev, i);
2905 else
2906 sci_port->irqs[i] = platform_get_irq(dev, i);
2907 }
2908
2909 /* The SCI generates several interrupts. They can be muxed together or
2910 * connected to different interrupt lines. In the muxed case only one
2911 * interrupt resource is specified as there is only one interrupt ID.
2912 * In the non-muxed case, up to 6 interrupt signals might be generated
2913 * from the SCI, however those signals might have their own individual
2914 * interrupt ID numbers, or muxed together with another interrupt.
2915 */
2916 if (sci_port->irqs[0] < 0)
2917 return -ENXIO;
2918
2919 if (sci_port->irqs[1] < 0)
2920 for (i = 1; i < ARRAY_SIZE(sci_port->irqs); i++)
2921 sci_port->irqs[i] = sci_port->irqs[0];
2922
2923 sci_port->params = sci_probe_regmap(p);
2924 if (unlikely(sci_port->params == NULL))
2925 return -EINVAL;
2926
2927 switch (p->type) {
2928 case PORT_SCIFB:
2929 sci_port->rx_trigger = 48;
2930 break;
2931 case PORT_HSCIF:
2932 sci_port->rx_trigger = 64;
2933 break;
2934 case PORT_SCIFA:
2935 sci_port->rx_trigger = 32;
2936 break;
2937 case PORT_SCIF:
2938 if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2939 /* RX triggering not implemented for this IP */
2940 sci_port->rx_trigger = 1;
2941 else
2942 sci_port->rx_trigger = 8;
2943 break;
2944 default:
2945 sci_port->rx_trigger = 1;
2946 break;
2947 }
2948
2949 sci_port->rx_fifo_timeout = 0;
2950 sci_port->hscif_tot = 0;
2951
2952 /* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2953 * match the SoC datasheet, this should be investigated. Let platform
2954 * data override the sampling rate for now.
2955 */
2956 sci_port->sampling_rate_mask = p->sampling_rate
2957 ? SCI_SR(p->sampling_rate)
2958 : sci_port->params->sampling_rate_mask;
2959
2960 if (!early) {
2961 ret = sci_init_clocks(sci_port, &dev->dev);
2962 if (ret < 0)
2963 return ret;
2964
2965 port->dev = &dev->dev;
2966
2967 pm_runtime_enable(&dev->dev);
2968 }
2969
2970 port->type = p->type;
2971 port->flags = UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2972 port->fifosize = sci_port->params->fifosize;
2973
2974 if (port->type == PORT_SCI) {
2975 if (sci_port->reg_size >= 0x20)
2976 port->regshift = 2;
2977 else
2978 port->regshift = 1;
2979 }
2980
2981 /*
2982 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2983 * for the multi-IRQ ports, which is where we are primarily
2984 * concerned with the shutdown path synchronization.
2985 *
2986 * For the muxed case there's nothing more to do.
2987 */
2988 port->irq = sci_port->irqs[SCIx_RXI_IRQ];
2989 port->irqflags = 0;
2990
2991 port->serial_in = sci_serial_in;
2992 port->serial_out = sci_serial_out;
2993
2994 return 0;
2995 }
2996
2997 static void sci_cleanup_single(struct sci_port *port)
2998 {
2999 pm_runtime_disable(port->port.dev);
3000 }
3001
3002 #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
3003 defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
3004 static void serial_console_putchar(struct uart_port *port, int ch)
3005 {
3006 sci_poll_put_char(port, ch);
3007 }
3008
3009 /*
3010 * Print a string to the serial port trying not to disturb
3011 * any possible real use of the port...
3012 */
3013 static void serial_console_write(struct console *co, const char *s,
3014 unsigned count)
3015 {
3016 struct sci_port *sci_port = &sci_ports[co->index];
3017 struct uart_port *port = &sci_port->port;
3018 unsigned short bits, ctrl, ctrl_temp;
3019 unsigned long flags;
3020 int locked = 1;
3021
3022 if (port->sysrq)
3023 locked = 0;
3024 else if (oops_in_progress)
3025 locked = spin_trylock_irqsave(&port->lock, flags);
3026 else
3027 spin_lock_irqsave(&port->lock, flags);
3028
3029 /* first save SCSCR then disable interrupts, keep clock source */
3030 ctrl = serial_port_in(port, SCSCR);
3031 ctrl_temp = SCSCR_RE | SCSCR_TE |
3032 (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
3033 (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
3034 serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
3035
3036 uart_console_write(port, s, count, serial_console_putchar);
3037
3038 /* wait until fifo is empty and last bit has been transmitted */
3039 bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
3040 while ((serial_port_in(port, SCxSR) & bits) != bits)
3041 cpu_relax();
3042
3043 /* restore the SCSCR */
3044 serial_port_out(port, SCSCR, ctrl);
3045
3046 if (locked)
3047 spin_unlock_irqrestore(&port->lock, flags);
3048 }
3049
3050 static int serial_console_setup(struct console *co, char *options)
3051 {
3052 struct sci_port *sci_port;
3053 struct uart_port *port;
3054 int baud = 115200;
3055 int bits = 8;
3056 int parity = 'n';
3057 int flow = 'n';
3058 int ret;
3059
3060 /*
3061 * Refuse to handle any bogus ports.
3062 */
3063 if (co->index < 0 || co->index >= SCI_NPORTS)
3064 return -ENODEV;
3065
3066 sci_port = &sci_ports[co->index];
3067 port = &sci_port->port;
3068
3069 /*
3070 * Refuse to handle uninitialized ports.
3071 */
3072 if (!port->ops)
3073 return -ENODEV;
3074
3075 ret = sci_remap_port(port);
3076 if (unlikely(ret != 0))
3077 return ret;
3078
3079 if (options)
3080 uart_parse_options(options, &baud, &parity, &bits, &flow);
3081
3082 return uart_set_options(port, co, baud, parity, bits, flow);
3083 }
3084
3085 static struct console serial_console = {
3086 .name = "ttySC",
3087 .device = uart_console_device,
3088 .write = serial_console_write,
3089 .setup = serial_console_setup,
3090 .flags = CON_PRINTBUFFER,
3091 .index = -1,
3092 .data = &sci_uart_driver,
3093 };
3094
3095 #ifdef CONFIG_SUPERH
3096 static struct console early_serial_console = {
3097 .name = "early_ttySC",
3098 .write = serial_console_write,
3099 .flags = CON_PRINTBUFFER,
3100 .index = -1,
3101 };
3102
3103 static char early_serial_buf[32];
3104
3105 static int sci_probe_earlyprintk(struct platform_device *pdev)
3106 {
3107 const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
3108
3109 if (early_serial_console.data)
3110 return -EEXIST;
3111
3112 early_serial_console.index = pdev->id;
3113
3114 sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
3115
3116 serial_console_setup(&early_serial_console, early_serial_buf);
3117
3118 if (!strstr(early_serial_buf, "keep"))
3119 early_serial_console.flags |= CON_BOOT;
3120
3121 register_console(&early_serial_console);
3122 return 0;
3123 }
3124 #endif
3125
3126 #define SCI_CONSOLE (&serial_console)
3127
3128 #else
3129 static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3130 {
3131 return -EINVAL;
3132 }
3133
3134 #define SCI_CONSOLE NULL
3135
3136 #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3137
3138 static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3139
3140 static DEFINE_MUTEX(sci_uart_registration_lock);
3141 static struct uart_driver sci_uart_driver = {
3142 .owner = THIS_MODULE,
3143 .driver_name = "sci",
3144 .dev_name = "ttySC",
3145 .major = SCI_MAJOR,
3146 .minor = SCI_MINOR_START,
3147 .nr = SCI_NPORTS,
3148 .cons = SCI_CONSOLE,
3149 };
3150
3151 static int sci_remove(struct platform_device *dev)
3152 {
3153 struct sci_port *port = platform_get_drvdata(dev);
3154 unsigned int type = port->port.type; /* uart_remove_... clears it */
3155
3156 sci_ports_in_use &= ~BIT(port->port.line);
3157 uart_remove_one_port(&sci_uart_driver, &port->port);
3158
3159 sci_cleanup_single(port);
3160
3161 if (port->port.fifosize > 1)
3162 device_remove_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3163 if (type == PORT_SCIFA || type == PORT_SCIFB || type == PORT_HSCIF)
3164 device_remove_file(&dev->dev, &dev_attr_rx_fifo_timeout);
3165
3166 return 0;
3167 }
3168
3169
3170 #define SCI_OF_DATA(type, regtype) (void *)((type) << 16 | (regtype))
3171 #define SCI_OF_TYPE(data) ((unsigned long)(data) >> 16)
3172 #define SCI_OF_REGTYPE(data) ((unsigned long)(data) & 0xffff)
3173
3174 static const struct of_device_id of_sci_match[] = {
3175 /* SoC-specific types */
3176 {
3177 .compatible = "renesas,scif-r7s72100",
3178 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3179 },
3180 {
3181 .compatible = "renesas,scif-r7s9210",
3182 .data = SCI_OF_DATA(PORT_SCIF, SCIx_RZ_SCIFA_REGTYPE),
3183 },
3184 /* Family-specific types */
3185 {
3186 .compatible = "renesas,rcar-gen1-scif",
3187 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3188 }, {
3189 .compatible = "renesas,rcar-gen2-scif",
3190 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3191 }, {
3192 .compatible = "renesas,rcar-gen3-scif",
3193 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3194 },
3195 /* Generic types */
3196 {
3197 .compatible = "renesas,scif",
3198 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3199 }, {
3200 .compatible = "renesas,scifa",
3201 .data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3202 }, {
3203 .compatible = "renesas,scifb",
3204 .data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3205 }, {
3206 .compatible = "renesas,hscif",
3207 .data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3208 }, {
3209 .compatible = "renesas,sci",
3210 .data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3211 }, {
3212 /* Terminator */
3213 },
3214 };
3215 MODULE_DEVICE_TABLE(of, of_sci_match);
3216
3217 static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3218 unsigned int *dev_id)
3219 {
3220 struct device_node *np = pdev->dev.of_node;
3221 struct plat_sci_port *p;
3222 struct sci_port *sp;
3223 const void *data;
3224 int id;
3225
3226 if (!IS_ENABLED(CONFIG_OF) || !np)
3227 return NULL;
3228
3229 data = of_device_get_match_data(&pdev->dev);
3230
3231 p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3232 if (!p)
3233 return NULL;
3234
3235 /* Get the line number from the aliases node. */
3236 id = of_alias_get_id(np, "serial");
3237 if (id < 0 && ~sci_ports_in_use)
3238 id = ffz(sci_ports_in_use);
3239 if (id < 0) {
3240 dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3241 return NULL;
3242 }
3243 if (id >= ARRAY_SIZE(sci_ports)) {
3244 dev_err(&pdev->dev, "serial%d out of range\n", id);
3245 return NULL;
3246 }
3247
3248 sp = &sci_ports[id];
3249 *dev_id = id;
3250
3251 p->type = SCI_OF_TYPE(data);
3252 p->regtype = SCI_OF_REGTYPE(data);
3253
3254 sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3255
3256 return p;
3257 }
3258
3259 static int sci_probe_single(struct platform_device *dev,
3260 unsigned int index,
3261 struct plat_sci_port *p,
3262 struct sci_port *sciport)
3263 {
3264 int ret;
3265
3266 /* Sanity check */
3267 if (unlikely(index >= SCI_NPORTS)) {
3268 dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3269 index+1, SCI_NPORTS);
3270 dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3271 return -EINVAL;
3272 }
3273 BUILD_BUG_ON(SCI_NPORTS > sizeof(sci_ports_in_use) * 8);
3274 if (sci_ports_in_use & BIT(index))
3275 return -EBUSY;
3276
3277 mutex_lock(&sci_uart_registration_lock);
3278 if (!sci_uart_driver.state) {
3279 ret = uart_register_driver(&sci_uart_driver);
3280 if (ret) {
3281 mutex_unlock(&sci_uart_registration_lock);
3282 return ret;
3283 }
3284 }
3285 mutex_unlock(&sci_uart_registration_lock);
3286
3287 ret = sci_init_single(dev, sciport, index, p, false);
3288 if (ret)
3289 return ret;
3290
3291 sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3292 if (IS_ERR(sciport->gpios))
3293 return PTR_ERR(sciport->gpios);
3294
3295 if (sciport->has_rtscts) {
3296 if (mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_CTS) ||
3297 mctrl_gpio_to_gpiod(sciport->gpios, UART_GPIO_RTS)) {
3298 dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3299 return -EINVAL;
3300 }
3301 sciport->port.flags |= UPF_HARD_FLOW;
3302 }
3303
3304 ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3305 if (ret) {
3306 sci_cleanup_single(sciport);
3307 return ret;
3308 }
3309
3310 return 0;
3311 }
3312
3313 static int sci_probe(struct platform_device *dev)
3314 {
3315 struct plat_sci_port *p;
3316 struct sci_port *sp;
3317 unsigned int dev_id;
3318 int ret;
3319
3320 /*
3321 * If we've come here via earlyprintk initialization, head off to
3322 * the special early probe. We don't have sufficient device state
3323 * to make it beyond this yet.
3324 */
3325 #ifdef CONFIG_SUPERH
3326 if (is_sh_early_platform_device(dev))
3327 return sci_probe_earlyprintk(dev);
3328 #endif
3329
3330 if (dev->dev.of_node) {
3331 p = sci_parse_dt(dev, &dev_id);
3332 if (p == NULL)
3333 return -EINVAL;
3334 } else {
3335 p = dev->dev.platform_data;
3336 if (p == NULL) {
3337 dev_err(&dev->dev, "no platform data supplied\n");
3338 return -EINVAL;
3339 }
3340
3341 dev_id = dev->id;
3342 }
3343
3344 sp = &sci_ports[dev_id];
3345 platform_set_drvdata(dev, sp);
3346
3347 ret = sci_probe_single(dev, dev_id, p, sp);
3348 if (ret)
3349 return ret;
3350
3351 if (sp->port.fifosize > 1) {
3352 ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_trigger);
3353 if (ret)
3354 return ret;
3355 }
3356 if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3357 sp->port.type == PORT_HSCIF) {
3358 ret = device_create_file(&dev->dev, &dev_attr_rx_fifo_timeout);
3359 if (ret) {
3360 if (sp->port.fifosize > 1) {
3361 device_remove_file(&dev->dev,
3362 &dev_attr_rx_fifo_trigger);
3363 }
3364 return ret;
3365 }
3366 }
3367
3368 #ifdef CONFIG_SH_STANDARD_BIOS
3369 sh_bios_gdb_detach();
3370 #endif
3371
3372 sci_ports_in_use |= BIT(dev_id);
3373 return 0;
3374 }
3375
3376 static __maybe_unused int sci_suspend(struct device *dev)
3377 {
3378 struct sci_port *sport = dev_get_drvdata(dev);
3379
3380 if (sport)
3381 uart_suspend_port(&sci_uart_driver, &sport->port);
3382
3383 return 0;
3384 }
3385
3386 static __maybe_unused int sci_resume(struct device *dev)
3387 {
3388 struct sci_port *sport = dev_get_drvdata(dev);
3389
3390 if (sport)
3391 uart_resume_port(&sci_uart_driver, &sport->port);
3392
3393 return 0;
3394 }
3395
3396 static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3397
3398 static struct platform_driver sci_driver = {
3399 .probe = sci_probe,
3400 .remove = sci_remove,
3401 .driver = {
3402 .name = "sh-sci",
3403 .pm = &sci_dev_pm_ops,
3404 .of_match_table = of_match_ptr(of_sci_match),
3405 },
3406 };
3407
3408 static int __init sci_init(void)
3409 {
3410 pr_info("%s\n", banner);
3411
3412 return platform_driver_register(&sci_driver);
3413 }
3414
3415 static void __exit sci_exit(void)
3416 {
3417 platform_driver_unregister(&sci_driver);
3418
3419 if (sci_uart_driver.state)
3420 uart_unregister_driver(&sci_uart_driver);
3421 }
3422
3423 #if defined(CONFIG_SUPERH) && defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
3424 sh_early_platform_init_buffer("earlyprintk", &sci_driver,
3425 early_serial_buf, ARRAY_SIZE(early_serial_buf));
3426 #endif
3427 #ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3428 static struct plat_sci_port port_cfg __initdata;
3429
3430 static int __init early_console_setup(struct earlycon_device *device,
3431 int type)
3432 {
3433 if (!device->port.membase)
3434 return -ENODEV;
3435
3436 device->port.serial_in = sci_serial_in;
3437 device->port.serial_out = sci_serial_out;
3438 device->port.type = type;
3439 memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3440 port_cfg.type = type;
3441 sci_ports[0].cfg = &port_cfg;
3442 sci_ports[0].params = sci_probe_regmap(&port_cfg);
3443 port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3444 sci_serial_out(&sci_ports[0].port, SCSCR,
3445 SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3446
3447 device->con->write = serial_console_write;
3448 return 0;
3449 }
3450 static int __init sci_early_console_setup(struct earlycon_device *device,
3451 const char *opt)
3452 {
3453 return early_console_setup(device, PORT_SCI);
3454 }
3455 static int __init scif_early_console_setup(struct earlycon_device *device,
3456 const char *opt)
3457 {
3458 return early_console_setup(device, PORT_SCIF);
3459 }
3460 static int __init rzscifa_early_console_setup(struct earlycon_device *device,
3461 const char *opt)
3462 {
3463 port_cfg.regtype = SCIx_RZ_SCIFA_REGTYPE;
3464 return early_console_setup(device, PORT_SCIF);
3465 }
3466 static int __init scifa_early_console_setup(struct earlycon_device *device,
3467 const char *opt)
3468 {
3469 return early_console_setup(device, PORT_SCIFA);
3470 }
3471 static int __init scifb_early_console_setup(struct earlycon_device *device,
3472 const char *opt)
3473 {
3474 return early_console_setup(device, PORT_SCIFB);
3475 }
3476 static int __init hscif_early_console_setup(struct earlycon_device *device,
3477 const char *opt)
3478 {
3479 return early_console_setup(device, PORT_HSCIF);
3480 }
3481
3482 OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3483 OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3484 OF_EARLYCON_DECLARE(scif, "renesas,scif-r7s9210", rzscifa_early_console_setup);
3485 OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3486 OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3487 OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3488 #endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3489
3490 module_init(sci_init);
3491 module_exit(sci_exit);
3492
3493 MODULE_LICENSE("GPL");
3494 MODULE_ALIAS("platform:sh-sci");
3495 MODULE_AUTHOR("Paul Mundt");
3496 MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
Linux with added FPC-III support