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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
4 *
5 * Copyright (C) 2002 - 2011 Paul Mundt
6 * Copyright (C) 2015 Glider bvba
7 * Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
8 *
9 * based off of the old drivers/char/sh-sci.c by:
10 *
11 * Copyright (C) 1999, 2000 Niibe Yutaka
12 * Copyright (C) 2000 Sugioka Toshinobu
13 * Modified to support multiple serial ports. Stuart Menefy (May 2000).
14 * Modified to support SecureEdge. David McCullough (2002)
15 * Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
16 * Removed SH7300 support (Jul 2007).
17 */
18#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
19#define SUPPORT_SYSRQ
20#endif
21
22#undef DEBUG
23
24#include <linux/clk.h>
25#include <linux/console.h>
26#include <linux/ctype.h>
27#include <linux/cpufreq.h>
28#include <linux/delay.h>
29#include <linux/dmaengine.h>
30#include <linux/dma-mapping.h>
31#include <linux/err.h>
32#include <linux/errno.h>
33#include <linux/init.h>
34#include <linux/interrupt.h>
35#include <linux/ioport.h>
36#include <linux/ktime.h>
37#include <linux/major.h>
38#include <linux/module.h>
39#include <linux/mm.h>
40#include <linux/of.h>
41#include <linux/of_device.h>
42#include <linux/platform_device.h>
43#include <linux/pm_runtime.h>
44#include <linux/scatterlist.h>
45#include <linux/serial.h>
46#include <linux/serial_sci.h>
47#include <linux/sh_dma.h>
48#include <linux/slab.h>
49#include <linux/string.h>
50#include <linux/sysrq.h>
51#include <linux/timer.h>
52#include <linux/tty.h>
53#include <linux/tty_flip.h>
54
55#ifdef CONFIG_SUPERH
56#include <asm/sh_bios.h>
57#endif
58
59#include "serial_mctrl_gpio.h"
60#include "sh-sci.h"
61
62/* Offsets into the sci_port->irqs array */
63enum {
64 SCIx_ERI_IRQ,
65 SCIx_RXI_IRQ,
66 SCIx_TXI_IRQ,
67 SCIx_BRI_IRQ,
68 SCIx_NR_IRQS,
69
70 SCIx_MUX_IRQ = SCIx_NR_IRQS, /* special case */
71};
72
73#define SCIx_IRQ_IS_MUXED(port) \
74 ((port)->irqs[SCIx_ERI_IRQ] == \
75 (port)->irqs[SCIx_RXI_IRQ]) || \
76 ((port)->irqs[SCIx_ERI_IRQ] && \
77 ((port)->irqs[SCIx_RXI_IRQ] < 0))
78
79enum SCI_CLKS {
80 SCI_FCK, /* Functional Clock */
81 SCI_SCK, /* Optional External Clock */
82 SCI_BRG_INT, /* Optional BRG Internal Clock Source */
83 SCI_SCIF_CLK, /* Optional BRG External Clock Source */
84 SCI_NUM_CLKS
85};
86
87/* Bit x set means sampling rate x + 1 is supported */
88#define SCI_SR(x) BIT((x) - 1)
89#define SCI_SR_RANGE(x, y) GENMASK((y) - 1, (x) - 1)
90
91#define SCI_SR_SCIFAB SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
92 SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
93 SCI_SR(19) | SCI_SR(27)
94
95#define min_sr(_port) ffs((_port)->sampling_rate_mask)
96#define max_sr(_port) fls((_port)->sampling_rate_mask)
97
98/* Iterate over all supported sampling rates, from high to low */
99#define for_each_sr(_sr, _port) \
100 for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--) \
101 if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
102
103struct plat_sci_reg {
104 u8 offset, size;
105};
106
107struct sci_port_params {
108 const struct plat_sci_reg regs[SCIx_NR_REGS];
109 unsigned int fifosize;
110 unsigned int overrun_reg;
111 unsigned int overrun_mask;
112 unsigned int sampling_rate_mask;
113 unsigned int error_mask;
114 unsigned int error_clear;
115};
116
117struct sci_port {
118 struct uart_port port;
119
120 /* Platform configuration */
121 const struct sci_port_params *params;
122 const struct plat_sci_port *cfg;
123 unsigned int sampling_rate_mask;
124 resource_size_t reg_size;
125 struct mctrl_gpios *gpios;
126
127 /* Clocks */
128 struct clk *clks[SCI_NUM_CLKS];
129 unsigned long clk_rates[SCI_NUM_CLKS];
130
131 int irqs[SCIx_NR_IRQS];
132 char *irqstr[SCIx_NR_IRQS];
133
134 struct dma_chan *chan_tx;
135 struct dma_chan *chan_rx;
136
137#ifdef CONFIG_SERIAL_SH_SCI_DMA
138 dma_cookie_t cookie_tx;
139 dma_cookie_t cookie_rx[2];
140 dma_cookie_t active_rx;
141 dma_addr_t tx_dma_addr;
142 unsigned int tx_dma_len;
143 struct scatterlist sg_rx[2];
144 void *rx_buf[2];
145 size_t buf_len_rx;
146 struct work_struct work_tx;
147 struct hrtimer rx_timer;
148 unsigned int rx_timeout; /* microseconds */
149#endif
150 unsigned int rx_frame;
151 int rx_trigger;
152 struct timer_list rx_fifo_timer;
153 int rx_fifo_timeout;
154 u16 hscif_tot;
155
156 bool has_rtscts;
157 bool autorts;
158};
159
160#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
161
162static struct sci_port sci_ports[SCI_NPORTS];
163static struct uart_driver sci_uart_driver;
164
165static inline struct sci_port *
166to_sci_port(struct uart_port *uart)
167{
168 return container_of(uart, struct sci_port, port);
169}
170
171static const struct sci_port_params sci_port_params[SCIx_NR_REGTYPES] = {
172 /*
173 * Common SCI definitions, dependent on the port's regshift
174 * value.
175 */
176 [SCIx_SCI_REGTYPE] = {
177 .regs = {
178 [SCSMR] = { 0x00, 8 },
179 [SCBRR] = { 0x01, 8 },
180 [SCSCR] = { 0x02, 8 },
181 [SCxTDR] = { 0x03, 8 },
182 [SCxSR] = { 0x04, 8 },
183 [SCxRDR] = { 0x05, 8 },
184 },
185 .fifosize = 1,
186 .overrun_reg = SCxSR,
187 .overrun_mask = SCI_ORER,
188 .sampling_rate_mask = SCI_SR(32),
189 .error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
190 .error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
191 },
192
193 /*
194 * Common definitions for legacy IrDA ports.
195 */
196 [SCIx_IRDA_REGTYPE] = {
197 .regs = {
198 [SCSMR] = { 0x00, 8 },
199 [SCBRR] = { 0x02, 8 },
200 [SCSCR] = { 0x04, 8 },
201 [SCxTDR] = { 0x06, 8 },
202 [SCxSR] = { 0x08, 16 },
203 [SCxRDR] = { 0x0a, 8 },
204 [SCFCR] = { 0x0c, 8 },
205 [SCFDR] = { 0x0e, 16 },
206 },
207 .fifosize = 1,
208 .overrun_reg = SCxSR,
209 .overrun_mask = SCI_ORER,
210 .sampling_rate_mask = SCI_SR(32),
211 .error_mask = SCI_DEFAULT_ERROR_MASK | SCI_ORER,
212 .error_clear = SCI_ERROR_CLEAR & ~SCI_ORER,
213 },
214
215 /*
216 * Common SCIFA definitions.
217 */
218 [SCIx_SCIFA_REGTYPE] = {
219 .regs = {
220 [SCSMR] = { 0x00, 16 },
221 [SCBRR] = { 0x04, 8 },
222 [SCSCR] = { 0x08, 16 },
223 [SCxTDR] = { 0x20, 8 },
224 [SCxSR] = { 0x14, 16 },
225 [SCxRDR] = { 0x24, 8 },
226 [SCFCR] = { 0x18, 16 },
227 [SCFDR] = { 0x1c, 16 },
228 [SCPCR] = { 0x30, 16 },
229 [SCPDR] = { 0x34, 16 },
230 },
231 .fifosize = 64,
232 .overrun_reg = SCxSR,
233 .overrun_mask = SCIFA_ORER,
234 .sampling_rate_mask = SCI_SR_SCIFAB,
235 .error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
236 .error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
237 },
238
239 /*
240 * Common SCIFB definitions.
241 */
242 [SCIx_SCIFB_REGTYPE] = {
243 .regs = {
244 [SCSMR] = { 0x00, 16 },
245 [SCBRR] = { 0x04, 8 },
246 [SCSCR] = { 0x08, 16 },
247 [SCxTDR] = { 0x40, 8 },
248 [SCxSR] = { 0x14, 16 },
249 [SCxRDR] = { 0x60, 8 },
250 [SCFCR] = { 0x18, 16 },
251 [SCTFDR] = { 0x38, 16 },
252 [SCRFDR] = { 0x3c, 16 },
253 [SCPCR] = { 0x30, 16 },
254 [SCPDR] = { 0x34, 16 },
255 },
256 .fifosize = 256,
257 .overrun_reg = SCxSR,
258 .overrun_mask = SCIFA_ORER,
259 .sampling_rate_mask = SCI_SR_SCIFAB,
260 .error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
261 .error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
262 },
263
264 /*
265 * Common SH-2(A) SCIF definitions for ports with FIFO data
266 * count registers.
267 */
268 [SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
269 .regs = {
270 [SCSMR] = { 0x00, 16 },
271 [SCBRR] = { 0x04, 8 },
272 [SCSCR] = { 0x08, 16 },
273 [SCxTDR] = { 0x0c, 8 },
274 [SCxSR] = { 0x10, 16 },
275 [SCxRDR] = { 0x14, 8 },
276 [SCFCR] = { 0x18, 16 },
277 [SCFDR] = { 0x1c, 16 },
278 [SCSPTR] = { 0x20, 16 },
279 [SCLSR] = { 0x24, 16 },
280 },
281 .fifosize = 16,
282 .overrun_reg = SCLSR,
283 .overrun_mask = SCLSR_ORER,
284 .sampling_rate_mask = SCI_SR(32),
285 .error_mask = SCIF_DEFAULT_ERROR_MASK,
286 .error_clear = SCIF_ERROR_CLEAR,
287 },
288
289 /*
290 * Common SH-3 SCIF definitions.
291 */
292 [SCIx_SH3_SCIF_REGTYPE] = {
293 .regs = {
294 [SCSMR] = { 0x00, 8 },
295 [SCBRR] = { 0x02, 8 },
296 [SCSCR] = { 0x04, 8 },
297 [SCxTDR] = { 0x06, 8 },
298 [SCxSR] = { 0x08, 16 },
299 [SCxRDR] = { 0x0a, 8 },
300 [SCFCR] = { 0x0c, 8 },
301 [SCFDR] = { 0x0e, 16 },
302 },
303 .fifosize = 16,
304 .overrun_reg = SCLSR,
305 .overrun_mask = SCLSR_ORER,
306 .sampling_rate_mask = SCI_SR(32),
307 .error_mask = SCIF_DEFAULT_ERROR_MASK,
308 .error_clear = SCIF_ERROR_CLEAR,
309 },
310
311 /*
312 * Common SH-4(A) SCIF(B) definitions.
313 */
314 [SCIx_SH4_SCIF_REGTYPE] = {
315 .regs = {
316 [SCSMR] = { 0x00, 16 },
317 [SCBRR] = { 0x04, 8 },
318 [SCSCR] = { 0x08, 16 },
319 [SCxTDR] = { 0x0c, 8 },
320 [SCxSR] = { 0x10, 16 },
321 [SCxRDR] = { 0x14, 8 },
322 [SCFCR] = { 0x18, 16 },
323 [SCFDR] = { 0x1c, 16 },
324 [SCSPTR] = { 0x20, 16 },
325 [SCLSR] = { 0x24, 16 },
326 },
327 .fifosize = 16,
328 .overrun_reg = SCLSR,
329 .overrun_mask = SCLSR_ORER,
330 .sampling_rate_mask = SCI_SR(32),
331 .error_mask = SCIF_DEFAULT_ERROR_MASK,
332 .error_clear = SCIF_ERROR_CLEAR,
333 },
334
335 /*
336 * Common SCIF definitions for ports with a Baud Rate Generator for
337 * External Clock (BRG).
338 */
339 [SCIx_SH4_SCIF_BRG_REGTYPE] = {
340 .regs = {
341 [SCSMR] = { 0x00, 16 },
342 [SCBRR] = { 0x04, 8 },
343 [SCSCR] = { 0x08, 16 },
344 [SCxTDR] = { 0x0c, 8 },
345 [SCxSR] = { 0x10, 16 },
346 [SCxRDR] = { 0x14, 8 },
347 [SCFCR] = { 0x18, 16 },
348 [SCFDR] = { 0x1c, 16 },
349 [SCSPTR] = { 0x20, 16 },
350 [SCLSR] = { 0x24, 16 },
351 [SCDL] = { 0x30, 16 },
352 [SCCKS] = { 0x34, 16 },
353 },
354 .fifosize = 16,
355 .overrun_reg = SCLSR,
356 .overrun_mask = SCLSR_ORER,
357 .sampling_rate_mask = SCI_SR(32),
358 .error_mask = SCIF_DEFAULT_ERROR_MASK,
359 .error_clear = SCIF_ERROR_CLEAR,
360 },
361
362 /*
363 * Common HSCIF definitions.
364 */
365 [SCIx_HSCIF_REGTYPE] = {
366 .regs = {
367 [SCSMR] = { 0x00, 16 },
368 [SCBRR] = { 0x04, 8 },
369 [SCSCR] = { 0x08, 16 },
370 [SCxTDR] = { 0x0c, 8 },
371 [SCxSR] = { 0x10, 16 },
372 [SCxRDR] = { 0x14, 8 },
373 [SCFCR] = { 0x18, 16 },
374 [SCFDR] = { 0x1c, 16 },
375 [SCSPTR] = { 0x20, 16 },
376 [SCLSR] = { 0x24, 16 },
377 [HSSRR] = { 0x40, 16 },
378 [SCDL] = { 0x30, 16 },
379 [SCCKS] = { 0x34, 16 },
380 [HSRTRGR] = { 0x54, 16 },
381 [HSTTRGR] = { 0x58, 16 },
382 },
383 .fifosize = 128,
384 .overrun_reg = SCLSR,
385 .overrun_mask = SCLSR_ORER,
386 .sampling_rate_mask = SCI_SR_RANGE(8, 32),
387 .error_mask = SCIF_DEFAULT_ERROR_MASK,
388 .error_clear = SCIF_ERROR_CLEAR,
389 },
390
391 /*
392 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
393 * register.
394 */
395 [SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
396 .regs = {
397 [SCSMR] = { 0x00, 16 },
398 [SCBRR] = { 0x04, 8 },
399 [SCSCR] = { 0x08, 16 },
400 [SCxTDR] = { 0x0c, 8 },
401 [SCxSR] = { 0x10, 16 },
402 [SCxRDR] = { 0x14, 8 },
403 [SCFCR] = { 0x18, 16 },
404 [SCFDR] = { 0x1c, 16 },
405 [SCLSR] = { 0x24, 16 },
406 },
407 .fifosize = 16,
408 .overrun_reg = SCLSR,
409 .overrun_mask = SCLSR_ORER,
410 .sampling_rate_mask = SCI_SR(32),
411 .error_mask = SCIF_DEFAULT_ERROR_MASK,
412 .error_clear = SCIF_ERROR_CLEAR,
413 },
414
415 /*
416 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
417 * count registers.
418 */
419 [SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
420 .regs = {
421 [SCSMR] = { 0x00, 16 },
422 [SCBRR] = { 0x04, 8 },
423 [SCSCR] = { 0x08, 16 },
424 [SCxTDR] = { 0x0c, 8 },
425 [SCxSR] = { 0x10, 16 },
426 [SCxRDR] = { 0x14, 8 },
427 [SCFCR] = { 0x18, 16 },
428 [SCFDR] = { 0x1c, 16 },
429 [SCTFDR] = { 0x1c, 16 }, /* aliased to SCFDR */
430 [SCRFDR] = { 0x20, 16 },
431 [SCSPTR] = { 0x24, 16 },
432 [SCLSR] = { 0x28, 16 },
433 },
434 .fifosize = 16,
435 .overrun_reg = SCLSR,
436 .overrun_mask = SCLSR_ORER,
437 .sampling_rate_mask = SCI_SR(32),
438 .error_mask = SCIF_DEFAULT_ERROR_MASK,
439 .error_clear = SCIF_ERROR_CLEAR,
440 },
441
442 /*
443 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
444 * registers.
445 */
446 [SCIx_SH7705_SCIF_REGTYPE] = {
447 .regs = {
448 [SCSMR] = { 0x00, 16 },
449 [SCBRR] = { 0x04, 8 },
450 [SCSCR] = { 0x08, 16 },
451 [SCxTDR] = { 0x20, 8 },
452 [SCxSR] = { 0x14, 16 },
453 [SCxRDR] = { 0x24, 8 },
454 [SCFCR] = { 0x18, 16 },
455 [SCFDR] = { 0x1c, 16 },
456 },
457 .fifosize = 64,
458 .overrun_reg = SCxSR,
459 .overrun_mask = SCIFA_ORER,
460 .sampling_rate_mask = SCI_SR(16),
461 .error_mask = SCIF_DEFAULT_ERROR_MASK | SCIFA_ORER,
462 .error_clear = SCIF_ERROR_CLEAR & ~SCIFA_ORER,
463 },
464};
465
466#define sci_getreg(up, offset) (&to_sci_port(up)->params->regs[offset])
467
468/*
469 * The "offset" here is rather misleading, in that it refers to an enum
470 * value relative to the port mapping rather than the fixed offset
471 * itself, which needs to be manually retrieved from the platform's
472 * register map for the given port.
473 */
474static unsigned int sci_serial_in(struct uart_port *p, int offset)
475{
476 const struct plat_sci_reg *reg = sci_getreg(p, offset);
477
478 if (reg->size == 8)
479 return ioread8(p->membase + (reg->offset << p->regshift));
480 else if (reg->size == 16)
481 return ioread16(p->membase + (reg->offset << p->regshift));
482 else
483 WARN(1, "Invalid register access\n");
484
485 return 0;
486}
487
488static void sci_serial_out(struct uart_port *p, int offset, int value)
489{
490 const struct plat_sci_reg *reg = sci_getreg(p, offset);
491
492 if (reg->size == 8)
493 iowrite8(value, p->membase + (reg->offset << p->regshift));
494 else if (reg->size == 16)
495 iowrite16(value, p->membase + (reg->offset << p->regshift));
496 else
497 WARN(1, "Invalid register access\n");
498}
499
500static void sci_port_enable(struct sci_port *sci_port)
501{
502 unsigned int i;
503
504 if (!sci_port->port.dev)
505 return;
506
507 pm_runtime_get_sync(sci_port->port.dev);
508
509 for (i = 0; i < SCI_NUM_CLKS; i++) {
510 clk_prepare_enable(sci_port->clks[i]);
511 sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
512 }
513 sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
514}
515
516static void sci_port_disable(struct sci_port *sci_port)
517{
518 unsigned int i;
519
520 if (!sci_port->port.dev)
521 return;
522
523 for (i = SCI_NUM_CLKS; i-- > 0; )
524 clk_disable_unprepare(sci_port->clks[i]);
525
526 pm_runtime_put_sync(sci_port->port.dev);
527}
528
529static inline unsigned long port_rx_irq_mask(struct uart_port *port)
530{
531 /*
532 * Not all ports (such as SCIFA) will support REIE. Rather than
533 * special-casing the port type, we check the port initialization
534 * IRQ enable mask to see whether the IRQ is desired at all. If
535 * it's unset, it's logically inferred that there's no point in
536 * testing for it.
537 */
538 return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
539}
540
541static void sci_start_tx(struct uart_port *port)
542{
543 struct sci_port *s = to_sci_port(port);
544 unsigned short ctrl;
545
546#ifdef CONFIG_SERIAL_SH_SCI_DMA
547 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
548 u16 new, scr = serial_port_in(port, SCSCR);
549 if (s->chan_tx)
550 new = scr | SCSCR_TDRQE;
551 else
552 new = scr & ~SCSCR_TDRQE;
553 if (new != scr)
554 serial_port_out(port, SCSCR, new);
555 }
556
557 if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
558 dma_submit_error(s->cookie_tx)) {
559 s->cookie_tx = 0;
560 schedule_work(&s->work_tx);
561 }
562#endif
563
564 if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
565 /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
566 ctrl = serial_port_in(port, SCSCR);
567 serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
568 }
569}
570
571static void sci_stop_tx(struct uart_port *port)
572{
573 unsigned short ctrl;
574
575 /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
576 ctrl = serial_port_in(port, SCSCR);
577
578 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
579 ctrl &= ~SCSCR_TDRQE;
580
581 ctrl &= ~SCSCR_TIE;
582
583 serial_port_out(port, SCSCR, ctrl);
584}
585
586static void sci_start_rx(struct uart_port *port)
587{
588 unsigned short ctrl;
589
590 ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
591
592 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
593 ctrl &= ~SCSCR_RDRQE;
594
595 serial_port_out(port, SCSCR, ctrl);
596}
597
598static void sci_stop_rx(struct uart_port *port)
599{
600 unsigned short ctrl;
601
602 ctrl = serial_port_in(port, SCSCR);
603
604 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
605 ctrl &= ~SCSCR_RDRQE;
606
607 ctrl &= ~port_rx_irq_mask(port);
608
609 serial_port_out(port, SCSCR, ctrl);
610}
611
612static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
613{
614 if (port->type == PORT_SCI) {
615 /* Just store the mask */
616 serial_port_out(port, SCxSR, mask);
617 } else if (to_sci_port(port)->params->overrun_mask == SCIFA_ORER) {
618 /* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */
619 /* Only clear the status bits we want to clear */
620 serial_port_out(port, SCxSR,
621 serial_port_in(port, SCxSR) & mask);
622 } else {
623 /* Store the mask, clear parity/framing errors */
624 serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC));
625 }
626}
627
628#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
629 defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
630
631#ifdef CONFIG_CONSOLE_POLL
632static int sci_poll_get_char(struct uart_port *port)
633{
634 unsigned short status;
635 int c;
636
637 do {
638 status = serial_port_in(port, SCxSR);
639 if (status & SCxSR_ERRORS(port)) {
640 sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
641 continue;
642 }
643 break;
644 } while (1);
645
646 if (!(status & SCxSR_RDxF(port)))
647 return NO_POLL_CHAR;
648
649 c = serial_port_in(port, SCxRDR);
650
651 /* Dummy read */
652 serial_port_in(port, SCxSR);
653 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
654
655 return c;
656}
657#endif
658
659static void sci_poll_put_char(struct uart_port *port, unsigned char c)
660{
661 unsigned short status;
662
663 do {
664 status = serial_port_in(port, SCxSR);
665 } while (!(status & SCxSR_TDxE(port)));
666
667 serial_port_out(port, SCxTDR, c);
668 sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
669}
670#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
671 CONFIG_SERIAL_SH_SCI_EARLYCON */
672
673static void sci_init_pins(struct uart_port *port, unsigned int cflag)
674{
675 struct sci_port *s = to_sci_port(port);
676
677 /*
678 * Use port-specific handler if provided.
679 */
680 if (s->cfg->ops && s->cfg->ops->init_pins) {
681 s->cfg->ops->init_pins(port, cflag);
682 return;
683 }
684
685 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
686 u16 data = serial_port_in(port, SCPDR);
687 u16 ctrl = serial_port_in(port, SCPCR);
688
689 /* Enable RXD and TXD pin functions */
690 ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC);
691 if (to_sci_port(port)->has_rtscts) {
692 /* RTS# is output, active low, unless autorts */
693 if (!(port->mctrl & TIOCM_RTS)) {
694 ctrl |= SCPCR_RTSC;
695 data |= SCPDR_RTSD;
696 } else if (!s->autorts) {
697 ctrl |= SCPCR_RTSC;
698 data &= ~SCPDR_RTSD;
699 } else {
700 /* Enable RTS# pin function */
701 ctrl &= ~SCPCR_RTSC;
702 }
703 /* Enable CTS# pin function */
704 ctrl &= ~SCPCR_CTSC;
705 }
706 serial_port_out(port, SCPDR, data);
707 serial_port_out(port, SCPCR, ctrl);
708 } else if (sci_getreg(port, SCSPTR)->size) {
709 u16 status = serial_port_in(port, SCSPTR);
710
711 /* RTS# is always output; and active low, unless autorts */
712 status |= SCSPTR_RTSIO;
713 if (!(port->mctrl & TIOCM_RTS))
714 status |= SCSPTR_RTSDT;
715 else if (!s->autorts)
716 status &= ~SCSPTR_RTSDT;
717 /* CTS# and SCK are inputs */
718 status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO);
719 serial_port_out(port, SCSPTR, status);
720 }
721}
722
723static int sci_txfill(struct uart_port *port)
724{
725 struct sci_port *s = to_sci_port(port);
726 unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
727 const struct plat_sci_reg *reg;
728
729 reg = sci_getreg(port, SCTFDR);
730 if (reg->size)
731 return serial_port_in(port, SCTFDR) & fifo_mask;
732
733 reg = sci_getreg(port, SCFDR);
734 if (reg->size)
735 return serial_port_in(port, SCFDR) >> 8;
736
737 return !(serial_port_in(port, SCxSR) & SCI_TDRE);
738}
739
740static int sci_txroom(struct uart_port *port)
741{
742 return port->fifosize - sci_txfill(port);
743}
744
745static int sci_rxfill(struct uart_port *port)
746{
747 struct sci_port *s = to_sci_port(port);
748 unsigned int fifo_mask = (s->params->fifosize << 1) - 1;
749 const struct plat_sci_reg *reg;
750
751 reg = sci_getreg(port, SCRFDR);
752 if (reg->size)
753 return serial_port_in(port, SCRFDR) & fifo_mask;
754
755 reg = sci_getreg(port, SCFDR);
756 if (reg->size)
757 return serial_port_in(port, SCFDR) & fifo_mask;
758
759 return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
760}
761
762/* ********************************************************************** *
763 * the interrupt related routines *
764 * ********************************************************************** */
765
766static void sci_transmit_chars(struct uart_port *port)
767{
768 struct circ_buf *xmit = &port->state->xmit;
769 unsigned int stopped = uart_tx_stopped(port);
770 unsigned short status;
771 unsigned short ctrl;
772 int count;
773
774 status = serial_port_in(port, SCxSR);
775 if (!(status & SCxSR_TDxE(port))) {
776 ctrl = serial_port_in(port, SCSCR);
777 if (uart_circ_empty(xmit))
778 ctrl &= ~SCSCR_TIE;
779 else
780 ctrl |= SCSCR_TIE;
781 serial_port_out(port, SCSCR, ctrl);
782 return;
783 }
784
785 count = sci_txroom(port);
786
787 do {
788 unsigned char c;
789
790 if (port->x_char) {
791 c = port->x_char;
792 port->x_char = 0;
793 } else if (!uart_circ_empty(xmit) && !stopped) {
794 c = xmit->buf[xmit->tail];
795 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
796 } else {
797 break;
798 }
799
800 serial_port_out(port, SCxTDR, c);
801
802 port->icount.tx++;
803 } while (--count > 0);
804
805 sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
806
807 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
808 uart_write_wakeup(port);
809 if (uart_circ_empty(xmit)) {
810 sci_stop_tx(port);
811 } else {
812 ctrl = serial_port_in(port, SCSCR);
813
814 if (port->type != PORT_SCI) {
815 serial_port_in(port, SCxSR); /* Dummy read */
816 sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port));
817 }
818
819 ctrl |= SCSCR_TIE;
820 serial_port_out(port, SCSCR, ctrl);
821 }
822}
823
824/* On SH3, SCIF may read end-of-break as a space->mark char */
825#define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); })
826
827static void sci_receive_chars(struct uart_port *port)
828{
829 struct tty_port *tport = &port->state->port;
830 int i, count, copied = 0;
831 unsigned short status;
832 unsigned char flag;
833
834 status = serial_port_in(port, SCxSR);
835 if (!(status & SCxSR_RDxF(port)))
836 return;
837
838 while (1) {
839 /* Don't copy more bytes than there is room for in the buffer */
840 count = tty_buffer_request_room(tport, sci_rxfill(port));
841
842 /* If for any reason we can't copy more data, we're done! */
843 if (count == 0)
844 break;
845
846 if (port->type == PORT_SCI) {
847 char c = serial_port_in(port, SCxRDR);
848 if (uart_handle_sysrq_char(port, c))
849 count = 0;
850 else
851 tty_insert_flip_char(tport, c, TTY_NORMAL);
852 } else {
853 for (i = 0; i < count; i++) {
854 char c = serial_port_in(port, SCxRDR);
855
856 status = serial_port_in(port, SCxSR);
857 if (uart_handle_sysrq_char(port, c)) {
858 count--; i--;
859 continue;
860 }
861
862 /* Store data and status */
863 if (status & SCxSR_FER(port)) {
864 flag = TTY_FRAME;
865 port->icount.frame++;
866 dev_notice(port->dev, "frame error\n");
867 } else if (status & SCxSR_PER(port)) {
868 flag = TTY_PARITY;
869 port->icount.parity++;
870 dev_notice(port->dev, "parity error\n");
871 } else
872 flag = TTY_NORMAL;
873
874 tty_insert_flip_char(tport, c, flag);
875 }
876 }
877
878 serial_port_in(port, SCxSR); /* dummy read */
879 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
880
881 copied += count;
882 port->icount.rx += count;
883 }
884
885 if (copied) {
886 /* Tell the rest of the system the news. New characters! */
887 tty_flip_buffer_push(tport);
888 } else {
889 /* TTY buffers full; read from RX reg to prevent lockup */
890 serial_port_in(port, SCxRDR);
891 serial_port_in(port, SCxSR); /* dummy read */
892 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
893 }
894}
895
896static int sci_handle_errors(struct uart_port *port)
897{
898 int copied = 0;
899 unsigned short status = serial_port_in(port, SCxSR);
900 struct tty_port *tport = &port->state->port;
901 struct sci_port *s = to_sci_port(port);
902
903 /* Handle overruns */
904 if (status & s->params->overrun_mask) {
905 port->icount.overrun++;
906
907 /* overrun error */
908 if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
909 copied++;
910
911 dev_notice(port->dev, "overrun error\n");
912 }
913
914 if (status & SCxSR_FER(port)) {
915 /* frame error */
916 port->icount.frame++;
917
918 if (tty_insert_flip_char(tport, 0, TTY_FRAME))
919 copied++;
920
921 dev_notice(port->dev, "frame error\n");
922 }
923
924 if (status & SCxSR_PER(port)) {
925 /* parity error */
926 port->icount.parity++;
927
928 if (tty_insert_flip_char(tport, 0, TTY_PARITY))
929 copied++;
930
931 dev_notice(port->dev, "parity error\n");
932 }
933
934 if (copied)
935 tty_flip_buffer_push(tport);
936
937 return copied;
938}
939
940static int sci_handle_fifo_overrun(struct uart_port *port)
941{
942 struct tty_port *tport = &port->state->port;
943 struct sci_port *s = to_sci_port(port);
944 const struct plat_sci_reg *reg;
945 int copied = 0;
946 u16 status;
947
948 reg = sci_getreg(port, s->params->overrun_reg);
949 if (!reg->size)
950 return 0;
951
952 status = serial_port_in(port, s->params->overrun_reg);
953 if (status & s->params->overrun_mask) {
954 status &= ~s->params->overrun_mask;
955 serial_port_out(port, s->params->overrun_reg, status);
956
957 port->icount.overrun++;
958
959 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
960 tty_flip_buffer_push(tport);
961
962 dev_dbg(port->dev, "overrun error\n");
963 copied++;
964 }
965
966 return copied;
967}
968
969static int sci_handle_breaks(struct uart_port *port)
970{
971 int copied = 0;
972 unsigned short status = serial_port_in(port, SCxSR);
973 struct tty_port *tport = &port->state->port;
974
975 if (uart_handle_break(port))
976 return 0;
977
978 if (status & SCxSR_BRK(port)) {
979 port->icount.brk++;
980
981 /* Notify of BREAK */
982 if (tty_insert_flip_char(tport, 0, TTY_BREAK))
983 copied++;
984
985 dev_dbg(port->dev, "BREAK detected\n");
986 }
987
988 if (copied)
989 tty_flip_buffer_push(tport);
990
991 copied += sci_handle_fifo_overrun(port);
992
993 return copied;
994}
995
996static int scif_set_rtrg(struct uart_port *port, int rx_trig)
997{
998 unsigned int bits;
999
1000 if (rx_trig < 1)
1001 rx_trig = 1;
1002 if (rx_trig >= port->fifosize)
1003 rx_trig = port->fifosize;
1004
1005 /* HSCIF can be set to an arbitrary level. */
1006 if (sci_getreg(port, HSRTRGR)->size) {
1007 serial_port_out(port, HSRTRGR, rx_trig);
1008 return rx_trig;
1009 }
1010
1011 switch (port->type) {
1012 case PORT_SCIF:
1013 if (rx_trig < 4) {
1014 bits = 0;
1015 rx_trig = 1;
1016 } else if (rx_trig < 8) {
1017 bits = SCFCR_RTRG0;
1018 rx_trig = 4;
1019 } else if (rx_trig < 14) {
1020 bits = SCFCR_RTRG1;
1021 rx_trig = 8;
1022 } else {
1023 bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1024 rx_trig = 14;
1025 }
1026 break;
1027 case PORT_SCIFA:
1028 case PORT_SCIFB:
1029 if (rx_trig < 16) {
1030 bits = 0;
1031 rx_trig = 1;
1032 } else if (rx_trig < 32) {
1033 bits = SCFCR_RTRG0;
1034 rx_trig = 16;
1035 } else if (rx_trig < 48) {
1036 bits = SCFCR_RTRG1;
1037 rx_trig = 32;
1038 } else {
1039 bits = SCFCR_RTRG0 | SCFCR_RTRG1;
1040 rx_trig = 48;
1041 }
1042 break;
1043 default:
1044 WARN(1, "unknown FIFO configuration");
1045 return 1;
1046 }
1047
1048 serial_port_out(port, SCFCR,
1049 (serial_port_in(port, SCFCR) &
1050 ~(SCFCR_RTRG1 | SCFCR_RTRG0)) | bits);
1051
1052 return rx_trig;
1053}
1054
1055static int scif_rtrg_enabled(struct uart_port *port)
1056{
1057 if (sci_getreg(port, HSRTRGR)->size)
1058 return serial_port_in(port, HSRTRGR) != 0;
1059 else
1060 return (serial_port_in(port, SCFCR) &
1061 (SCFCR_RTRG0 | SCFCR_RTRG1)) != 0;
1062}
1063
1064static void rx_fifo_timer_fn(struct timer_list *t)
1065{
1066 struct sci_port *s = from_timer(s, t, rx_fifo_timer);
1067 struct uart_port *port = &s->port;
1068
1069 dev_dbg(port->dev, "Rx timed out\n");
1070 scif_set_rtrg(port, 1);
1071}
1072
1073static ssize_t rx_trigger_show(struct device *dev,
1074 struct device_attribute *attr,
1075 char *buf)
1076{
1077 struct uart_port *port = dev_get_drvdata(dev);
1078 struct sci_port *sci = to_sci_port(port);
1079
1080 return sprintf(buf, "%d\n", sci->rx_trigger);
1081}
1082
1083static ssize_t rx_trigger_store(struct device *dev,
1084 struct device_attribute *attr,
1085 const char *buf,
1086 size_t count)
1087{
1088 struct uart_port *port = dev_get_drvdata(dev);
1089 struct sci_port *sci = to_sci_port(port);
1090 int ret;
1091 long r;
1092
1093 ret = kstrtol(buf, 0, &r);
1094 if (ret)
1095 return ret;
1096
1097 sci->rx_trigger = scif_set_rtrg(port, r);
1098 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1099 scif_set_rtrg(port, 1);
1100
1101 return count;
1102}
1103
1104static DEVICE_ATTR(rx_fifo_trigger, 0644, rx_trigger_show, rx_trigger_store);
1105
1106static ssize_t rx_fifo_timeout_show(struct device *dev,
1107 struct device_attribute *attr,
1108 char *buf)
1109{
1110 struct uart_port *port = dev_get_drvdata(dev);
1111 struct sci_port *sci = to_sci_port(port);
1112 int v;
1113
1114 if (port->type == PORT_HSCIF)
1115 v = sci->hscif_tot >> HSSCR_TOT_SHIFT;
1116 else
1117 v = sci->rx_fifo_timeout;
1118
1119 return sprintf(buf, "%d\n", v);
1120}
1121
1122static ssize_t rx_fifo_timeout_store(struct device *dev,
1123 struct device_attribute *attr,
1124 const char *buf,
1125 size_t count)
1126{
1127 struct uart_port *port = dev_get_drvdata(dev);
1128 struct sci_port *sci = to_sci_port(port);
1129 int ret;
1130 long r;
1131
1132 ret = kstrtol(buf, 0, &r);
1133 if (ret)
1134 return ret;
1135
1136 if (port->type == PORT_HSCIF) {
1137 if (r < 0 || r > 3)
1138 return -EINVAL;
1139 sci->hscif_tot = r << HSSCR_TOT_SHIFT;
1140 } else {
1141 sci->rx_fifo_timeout = r;
1142 scif_set_rtrg(port, 1);
1143 if (r > 0)
1144 timer_setup(&sci->rx_fifo_timer, rx_fifo_timer_fn, 0);
1145 }
1146
1147 return count;
1148}
1149
1150static DEVICE_ATTR_RW(rx_fifo_timeout);
1151
1152
1153#ifdef CONFIG_SERIAL_SH_SCI_DMA
1154static void sci_dma_tx_complete(void *arg)
1155{
1156 struct sci_port *s = arg;
1157 struct uart_port *port = &s->port;
1158 struct circ_buf *xmit = &port->state->xmit;
1159 unsigned long flags;
1160
1161 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1162
1163 spin_lock_irqsave(&port->lock, flags);
1164
1165 xmit->tail += s->tx_dma_len;
1166 xmit->tail &= UART_XMIT_SIZE - 1;
1167
1168 port->icount.tx += s->tx_dma_len;
1169
1170 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1171 uart_write_wakeup(port);
1172
1173 if (!uart_circ_empty(xmit)) {
1174 s->cookie_tx = 0;
1175 schedule_work(&s->work_tx);
1176 } else {
1177 s->cookie_tx = -EINVAL;
1178 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1179 u16 ctrl = serial_port_in(port, SCSCR);
1180 serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1181 }
1182 }
1183
1184 spin_unlock_irqrestore(&port->lock, flags);
1185}
1186
1187/* Locking: called with port lock held */
1188static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count)
1189{
1190 struct uart_port *port = &s->port;
1191 struct tty_port *tport = &port->state->port;
1192 int copied;
1193
1194 copied = tty_insert_flip_string(tport, buf, count);
1195 if (copied < count)
1196 port->icount.buf_overrun++;
1197
1198 port->icount.rx += copied;
1199
1200 return copied;
1201}
1202
1203static int sci_dma_rx_find_active(struct sci_port *s)
1204{
1205 unsigned int i;
1206
1207 for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++)
1208 if (s->active_rx == s->cookie_rx[i])
1209 return i;
1210
1211 return -1;
1212}
1213
1214static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
1215{
1216 struct dma_chan *chan = s->chan_rx;
1217 struct uart_port *port = &s->port;
1218 unsigned long flags;
1219
1220 spin_lock_irqsave(&port->lock, flags);
1221 s->chan_rx = NULL;
1222 s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1223 spin_unlock_irqrestore(&port->lock, flags);
1224 dmaengine_terminate_all(chan);
1225 dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0],
1226 sg_dma_address(&s->sg_rx[0]));
1227 dma_release_channel(chan);
1228 if (enable_pio) {
1229 spin_lock_irqsave(&port->lock, flags);
1230 sci_start_rx(port);
1231 spin_unlock_irqrestore(&port->lock, flags);
1232 }
1233}
1234
1235static void start_hrtimer_us(struct hrtimer *hrt, unsigned long usec)
1236{
1237 long sec = usec / 1000000;
1238 long nsec = (usec % 1000000) * 1000;
1239 ktime_t t = ktime_set(sec, nsec);
1240
1241 hrtimer_start(hrt, t, HRTIMER_MODE_REL);
1242}
1243
1244static void sci_dma_rx_complete(void *arg)
1245{
1246 struct sci_port *s = arg;
1247 struct dma_chan *chan = s->chan_rx;
1248 struct uart_port *port = &s->port;
1249 struct dma_async_tx_descriptor *desc;
1250 unsigned long flags;
1251 int active, count = 0;
1252
1253 dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line,
1254 s->active_rx);
1255
1256 spin_lock_irqsave(&port->lock, flags);
1257
1258 active = sci_dma_rx_find_active(s);
1259 if (active >= 0)
1260 count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx);
1261
1262 start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1263
1264 if (count)
1265 tty_flip_buffer_push(&port->state->port);
1266
1267 desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1,
1268 DMA_DEV_TO_MEM,
1269 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1270 if (!desc)
1271 goto fail;
1272
1273 desc->callback = sci_dma_rx_complete;
1274 desc->callback_param = s;
1275 s->cookie_rx[active] = dmaengine_submit(desc);
1276 if (dma_submit_error(s->cookie_rx[active]))
1277 goto fail;
1278
1279 s->active_rx = s->cookie_rx[!active];
1280
1281 dma_async_issue_pending(chan);
1282
1283 spin_unlock_irqrestore(&port->lock, flags);
1284 dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n",
1285 __func__, s->cookie_rx[active], active, s->active_rx);
1286 return;
1287
1288fail:
1289 spin_unlock_irqrestore(&port->lock, flags);
1290 dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1291 sci_rx_dma_release(s, true);
1292}
1293
1294static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
1295{
1296 struct dma_chan *chan = s->chan_tx;
1297 struct uart_port *port = &s->port;
1298 unsigned long flags;
1299
1300 spin_lock_irqsave(&port->lock, flags);
1301 s->chan_tx = NULL;
1302 s->cookie_tx = -EINVAL;
1303 spin_unlock_irqrestore(&port->lock, flags);
1304 dmaengine_terminate_all(chan);
1305 dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE,
1306 DMA_TO_DEVICE);
1307 dma_release_channel(chan);
1308 if (enable_pio) {
1309 spin_lock_irqsave(&port->lock, flags);
1310 sci_start_tx(port);
1311 spin_unlock_irqrestore(&port->lock, flags);
1312 }
1313}
1314
1315static void sci_submit_rx(struct sci_port *s)
1316{
1317 struct dma_chan *chan = s->chan_rx;
1318 int i;
1319
1320 for (i = 0; i < 2; i++) {
1321 struct scatterlist *sg = &s->sg_rx[i];
1322 struct dma_async_tx_descriptor *desc;
1323
1324 desc = dmaengine_prep_slave_sg(chan,
1325 sg, 1, DMA_DEV_TO_MEM,
1326 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1327 if (!desc)
1328 goto fail;
1329
1330 desc->callback = sci_dma_rx_complete;
1331 desc->callback_param = s;
1332 s->cookie_rx[i] = dmaengine_submit(desc);
1333 if (dma_submit_error(s->cookie_rx[i]))
1334 goto fail;
1335
1336 }
1337
1338 s->active_rx = s->cookie_rx[0];
1339
1340 dma_async_issue_pending(chan);
1341 return;
1342
1343fail:
1344 if (i)
1345 dmaengine_terminate_all(chan);
1346 for (i = 0; i < 2; i++)
1347 s->cookie_rx[i] = -EINVAL;
1348 s->active_rx = -EINVAL;
1349 sci_rx_dma_release(s, true);
1350}
1351
1352static void work_fn_tx(struct work_struct *work)
1353{
1354 struct sci_port *s = container_of(work, struct sci_port, work_tx);
1355 struct dma_async_tx_descriptor *desc;
1356 struct dma_chan *chan = s->chan_tx;
1357 struct uart_port *port = &s->port;
1358 struct circ_buf *xmit = &port->state->xmit;
1359 dma_addr_t buf;
1360
1361 /*
1362 * DMA is idle now.
1363 * Port xmit buffer is already mapped, and it is one page... Just adjust
1364 * offsets and lengths. Since it is a circular buffer, we have to
1365 * transmit till the end, and then the rest. Take the port lock to get a
1366 * consistent xmit buffer state.
1367 */
1368 spin_lock_irq(&port->lock);
1369 buf = s->tx_dma_addr + (xmit->tail & (UART_XMIT_SIZE - 1));
1370 s->tx_dma_len = min_t(unsigned int,
1371 CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1372 CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1373 spin_unlock_irq(&port->lock);
1374
1375 desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len,
1376 DMA_MEM_TO_DEV,
1377 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1378 if (!desc) {
1379 dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n");
1380 /* switch to PIO */
1381 sci_tx_dma_release(s, true);
1382 return;
1383 }
1384
1385 dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len,
1386 DMA_TO_DEVICE);
1387
1388 spin_lock_irq(&port->lock);
1389 desc->callback = sci_dma_tx_complete;
1390 desc->callback_param = s;
1391 spin_unlock_irq(&port->lock);
1392 s->cookie_tx = dmaengine_submit(desc);
1393 if (dma_submit_error(s->cookie_tx)) {
1394 dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1395 /* switch to PIO */
1396 sci_tx_dma_release(s, true);
1397 return;
1398 }
1399
1400 dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1401 __func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1402
1403 dma_async_issue_pending(chan);
1404}
1405
1406static enum hrtimer_restart rx_timer_fn(struct hrtimer *t)
1407{
1408 struct sci_port *s = container_of(t, struct sci_port, rx_timer);
1409 struct dma_chan *chan = s->chan_rx;
1410 struct uart_port *port = &s->port;
1411 struct dma_tx_state state;
1412 enum dma_status status;
1413 unsigned long flags;
1414 unsigned int read;
1415 int active, count;
1416 u16 scr;
1417
1418 dev_dbg(port->dev, "DMA Rx timed out\n");
1419
1420 spin_lock_irqsave(&port->lock, flags);
1421
1422 active = sci_dma_rx_find_active(s);
1423 if (active < 0) {
1424 spin_unlock_irqrestore(&port->lock, flags);
1425 return HRTIMER_NORESTART;
1426 }
1427
1428 status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1429 if (status == DMA_COMPLETE) {
1430 spin_unlock_irqrestore(&port->lock, flags);
1431 dev_dbg(port->dev, "Cookie %d #%d has already completed\n",
1432 s->active_rx, active);
1433
1434 /* Let packet complete handler take care of the packet */
1435 return HRTIMER_NORESTART;
1436 }
1437
1438 dmaengine_pause(chan);
1439
1440 /*
1441 * sometimes DMA transfer doesn't stop even if it is stopped and
1442 * data keeps on coming until transaction is complete so check
1443 * for DMA_COMPLETE again
1444 * Let packet complete handler take care of the packet
1445 */
1446 status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state);
1447 if (status == DMA_COMPLETE) {
1448 spin_unlock_irqrestore(&port->lock, flags);
1449 dev_dbg(port->dev, "Transaction complete after DMA engine was stopped");
1450 return HRTIMER_NORESTART;
1451 }
1452
1453 /* Handle incomplete DMA receive */
1454 dmaengine_terminate_all(s->chan_rx);
1455 read = sg_dma_len(&s->sg_rx[active]) - state.residue;
1456
1457 if (read) {
1458 count = sci_dma_rx_push(s, s->rx_buf[active], read);
1459 if (count)
1460 tty_flip_buffer_push(&port->state->port);
1461 }
1462
1463 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1464 sci_submit_rx(s);
1465
1466 /* Direct new serial port interrupts back to CPU */
1467 scr = serial_port_in(port, SCSCR);
1468 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1469 scr &= ~SCSCR_RDRQE;
1470 enable_irq(s->irqs[SCIx_RXI_IRQ]);
1471 }
1472 serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1473
1474 spin_unlock_irqrestore(&port->lock, flags);
1475
1476 return HRTIMER_NORESTART;
1477}
1478
1479static struct dma_chan *sci_request_dma_chan(struct uart_port *port,
1480 enum dma_transfer_direction dir)
1481{
1482 struct dma_chan *chan;
1483 struct dma_slave_config cfg;
1484 int ret;
1485
1486 chan = dma_request_slave_channel(port->dev,
1487 dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1488 if (!chan) {
1489 dev_warn(port->dev, "dma_request_slave_channel failed\n");
1490 return NULL;
1491 }
1492
1493 memset(&cfg, 0, sizeof(cfg));
1494 cfg.direction = dir;
1495 if (dir == DMA_MEM_TO_DEV) {
1496 cfg.dst_addr = port->mapbase +
1497 (sci_getreg(port, SCxTDR)->offset << port->regshift);
1498 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1499 } else {
1500 cfg.src_addr = port->mapbase +
1501 (sci_getreg(port, SCxRDR)->offset << port->regshift);
1502 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1503 }
1504
1505 ret = dmaengine_slave_config(chan, &cfg);
1506 if (ret) {
1507 dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret);
1508 dma_release_channel(chan);
1509 return NULL;
1510 }
1511
1512 return chan;
1513}
1514
1515static void sci_request_dma(struct uart_port *port)
1516{
1517 struct sci_port *s = to_sci_port(port);
1518 struct dma_chan *chan;
1519
1520 dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1521
1522 if (!port->dev->of_node)
1523 return;
1524
1525 s->cookie_tx = -EINVAL;
1526
1527 /*
1528 * Don't request a dma channel if no channel was specified
1529 * in the device tree.
1530 */
1531 if (!of_find_property(port->dev->of_node, "dmas", NULL))
1532 return;
1533
1534 chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV);
1535 dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1536 if (chan) {
1537 s->chan_tx = chan;
1538 /* UART circular tx buffer is an aligned page. */
1539 s->tx_dma_addr = dma_map_single(chan->device->dev,
1540 port->state->xmit.buf,
1541 UART_XMIT_SIZE,
1542 DMA_TO_DEVICE);
1543 if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) {
1544 dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n");
1545 dma_release_channel(chan);
1546 s->chan_tx = NULL;
1547 } else {
1548 dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n",
1549 __func__, UART_XMIT_SIZE,
1550 port->state->xmit.buf, &s->tx_dma_addr);
1551 }
1552
1553 INIT_WORK(&s->work_tx, work_fn_tx);
1554 }
1555
1556 chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM);
1557 dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1558 if (chan) {
1559 unsigned int i;
1560 dma_addr_t dma;
1561 void *buf;
1562
1563 s->chan_rx = chan;
1564
1565 s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize);
1566 buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2,
1567 &dma, GFP_KERNEL);
1568 if (!buf) {
1569 dev_warn(port->dev,
1570 "Failed to allocate Rx dma buffer, using PIO\n");
1571 dma_release_channel(chan);
1572 s->chan_rx = NULL;
1573 return;
1574 }
1575
1576 for (i = 0; i < 2; i++) {
1577 struct scatterlist *sg = &s->sg_rx[i];
1578
1579 sg_init_table(sg, 1);
1580 s->rx_buf[i] = buf;
1581 sg_dma_address(sg) = dma;
1582 sg_dma_len(sg) = s->buf_len_rx;
1583
1584 buf += s->buf_len_rx;
1585 dma += s->buf_len_rx;
1586 }
1587
1588 hrtimer_init(&s->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1589 s->rx_timer.function = rx_timer_fn;
1590
1591 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1592 sci_submit_rx(s);
1593 }
1594}
1595
1596static void sci_free_dma(struct uart_port *port)
1597{
1598 struct sci_port *s = to_sci_port(port);
1599
1600 if (s->chan_tx)
1601 sci_tx_dma_release(s, false);
1602 if (s->chan_rx)
1603 sci_rx_dma_release(s, false);
1604}
1605
1606static void sci_flush_buffer(struct uart_port *port)
1607{
1608 /*
1609 * In uart_flush_buffer(), the xmit circular buffer has just been
1610 * cleared, so we have to reset tx_dma_len accordingly.
1611 */
1612 to_sci_port(port)->tx_dma_len = 0;
1613}
1614#else /* !CONFIG_SERIAL_SH_SCI_DMA */
1615static inline void sci_request_dma(struct uart_port *port)
1616{
1617}
1618
1619static inline void sci_free_dma(struct uart_port *port)
1620{
1621}
1622
1623#define sci_flush_buffer NULL
1624#endif /* !CONFIG_SERIAL_SH_SCI_DMA */
1625
1626static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
1627{
1628 struct uart_port *port = ptr;
1629 struct sci_port *s = to_sci_port(port);
1630
1631#ifdef CONFIG_SERIAL_SH_SCI_DMA
1632 if (s->chan_rx) {
1633 u16 scr = serial_port_in(port, SCSCR);
1634 u16 ssr = serial_port_in(port, SCxSR);
1635
1636 /* Disable future Rx interrupts */
1637 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1638 disable_irq_nosync(irq);
1639 scr |= SCSCR_RDRQE;
1640 } else {
1641 scr &= ~SCSCR_RIE;
1642 sci_submit_rx(s);
1643 }
1644 serial_port_out(port, SCSCR, scr);
1645 /* Clear current interrupt */
1646 serial_port_out(port, SCxSR,
1647 ssr & ~(SCIF_DR | SCxSR_RDxF(port)));
1648 dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u us\n",
1649 jiffies, s->rx_timeout);
1650 start_hrtimer_us(&s->rx_timer, s->rx_timeout);
1651
1652 return IRQ_HANDLED;
1653 }
1654#endif
1655
1656 if (s->rx_trigger > 1 && s->rx_fifo_timeout > 0) {
1657 if (!scif_rtrg_enabled(port))
1658 scif_set_rtrg(port, s->rx_trigger);
1659
1660 mod_timer(&s->rx_fifo_timer, jiffies + DIV_ROUND_UP(
1661 s->rx_frame * HZ * s->rx_fifo_timeout, 1000000));
1662 }
1663
1664 /* I think sci_receive_chars has to be called irrespective
1665 * of whether the I_IXOFF is set, otherwise, how is the interrupt
1666 * to be disabled?
1667 */
1668 sci_receive_chars(ptr);
1669
1670 return IRQ_HANDLED;
1671}
1672
1673static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
1674{
1675 struct uart_port *port = ptr;
1676 unsigned long flags;
1677
1678 spin_lock_irqsave(&port->lock, flags);
1679 sci_transmit_chars(port);
1680 spin_unlock_irqrestore(&port->lock, flags);
1681
1682 return IRQ_HANDLED;
1683}
1684
1685static irqreturn_t sci_er_interrupt(int irq, void *ptr)
1686{
1687 struct uart_port *port = ptr;
1688 struct sci_port *s = to_sci_port(port);
1689
1690 /* Handle errors */
1691 if (port->type == PORT_SCI) {
1692 if (sci_handle_errors(port)) {
1693 /* discard character in rx buffer */
1694 serial_port_in(port, SCxSR);
1695 sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port));
1696 }
1697 } else {
1698 sci_handle_fifo_overrun(port);
1699 if (!s->chan_rx)
1700 sci_receive_chars(ptr);
1701 }
1702
1703 sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port));
1704
1705 /* Kick the transmission */
1706 if (!s->chan_tx)
1707 sci_tx_interrupt(irq, ptr);
1708
1709 return IRQ_HANDLED;
1710}
1711
1712static irqreturn_t sci_br_interrupt(int irq, void *ptr)
1713{
1714 struct uart_port *port = ptr;
1715
1716 /* Handle BREAKs */
1717 sci_handle_breaks(port);
1718 sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port));
1719
1720 return IRQ_HANDLED;
1721}
1722
1723static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
1724{
1725 unsigned short ssr_status, scr_status, err_enabled, orer_status = 0;
1726 struct uart_port *port = ptr;
1727 struct sci_port *s = to_sci_port(port);
1728 irqreturn_t ret = IRQ_NONE;
1729
1730 ssr_status = serial_port_in(port, SCxSR);
1731 scr_status = serial_port_in(port, SCSCR);
1732 if (s->params->overrun_reg == SCxSR)
1733 orer_status = ssr_status;
1734 else if (sci_getreg(port, s->params->overrun_reg)->size)
1735 orer_status = serial_port_in(port, s->params->overrun_reg);
1736
1737 err_enabled = scr_status & port_rx_irq_mask(port);
1738
1739 /* Tx Interrupt */
1740 if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1741 !s->chan_tx)
1742 ret = sci_tx_interrupt(irq, ptr);
1743
1744 /*
1745 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1746 * DR flags
1747 */
1748 if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1749 (scr_status & SCSCR_RIE))
1750 ret = sci_rx_interrupt(irq, ptr);
1751
1752 /* Error Interrupt */
1753 if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1754 ret = sci_er_interrupt(irq, ptr);
1755
1756 /* Break Interrupt */
1757 if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1758 ret = sci_br_interrupt(irq, ptr);
1759
1760 /* Overrun Interrupt */
1761 if (orer_status & s->params->overrun_mask) {
1762 sci_handle_fifo_overrun(port);
1763 ret = IRQ_HANDLED;
1764 }
1765
1766 return ret;
1767}
1768
1769static const struct sci_irq_desc {
1770 const char *desc;
1771 irq_handler_t handler;
1772} sci_irq_desc[] = {
1773 /*
1774 * Split out handlers, the default case.
1775 */
1776 [SCIx_ERI_IRQ] = {
1777 .desc = "rx err",
1778 .handler = sci_er_interrupt,
1779 },
1780
1781 [SCIx_RXI_IRQ] = {
1782 .desc = "rx full",
1783 .handler = sci_rx_interrupt,
1784 },
1785
1786 [SCIx_TXI_IRQ] = {
1787 .desc = "tx empty",
1788 .handler = sci_tx_interrupt,
1789 },
1790
1791 [SCIx_BRI_IRQ] = {
1792 .desc = "break",
1793 .handler = sci_br_interrupt,
1794 },
1795
1796 /*
1797 * Special muxed handler.
1798 */
1799 [SCIx_MUX_IRQ] = {
1800 .desc = "mux",
1801 .handler = sci_mpxed_interrupt,
1802 },
1803};
1804
1805static int sci_request_irq(struct sci_port *port)
1806{
1807 struct uart_port *up = &port->port;
1808 int i, j, ret = 0;
1809
1810 for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1811 const struct sci_irq_desc *desc;
1812 int irq;
1813
1814 if (SCIx_IRQ_IS_MUXED(port)) {
1815 i = SCIx_MUX_IRQ;
1816 irq = up->irq;
1817 } else {
1818 irq = port->irqs[i];
1819
1820 /*
1821 * Certain port types won't support all of the
1822 * available interrupt sources.
1823 */
1824 if (unlikely(irq < 0))
1825 continue;
1826 }
1827
1828 desc = sci_irq_desc + i;
1829 port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1830 dev_name(up->dev), desc->desc);
1831 if (!port->irqstr[j]) {
1832 ret = -ENOMEM;
1833 goto out_nomem;
1834 }
1835
1836 ret = request_irq(irq, desc->handler, up->irqflags,
1837 port->irqstr[j], port);
1838 if (unlikely(ret)) {
1839 dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1840 goto out_noirq;
1841 }
1842 }
1843
1844 return 0;
1845
1846out_noirq:
1847 while (--i >= 0)
1848 free_irq(port->irqs[i], port);
1849
1850out_nomem:
1851 while (--j >= 0)
1852 kfree(port->irqstr[j]);
1853
1854 return ret;
1855}
1856
1857static void sci_free_irq(struct sci_port *port)
1858{
1859 int i;
1860
1861 /*
1862 * Intentionally in reverse order so we iterate over the muxed
1863 * IRQ first.
1864 */
1865 for (i = 0; i < SCIx_NR_IRQS; i++) {
1866 int irq = port->irqs[i];
1867
1868 /*
1869 * Certain port types won't support all of the available
1870 * interrupt sources.
1871 */
1872 if (unlikely(irq < 0))
1873 continue;
1874
1875 free_irq(port->irqs[i], port);
1876 kfree(port->irqstr[i]);
1877
1878 if (SCIx_IRQ_IS_MUXED(port)) {
1879 /* If there's only one IRQ, we're done. */
1880 return;
1881 }
1882 }
1883}
1884
1885static unsigned int sci_tx_empty(struct uart_port *port)
1886{
1887 unsigned short status = serial_port_in(port, SCxSR);
1888 unsigned short in_tx_fifo = sci_txfill(port);
1889
1890 return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1891}
1892
1893static void sci_set_rts(struct uart_port *port, bool state)
1894{
1895 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1896 u16 data = serial_port_in(port, SCPDR);
1897
1898 /* Active low */
1899 if (state)
1900 data &= ~SCPDR_RTSD;
1901 else
1902 data |= SCPDR_RTSD;
1903 serial_port_out(port, SCPDR, data);
1904
1905 /* RTS# is output */
1906 serial_port_out(port, SCPCR,
1907 serial_port_in(port, SCPCR) | SCPCR_RTSC);
1908 } else if (sci_getreg(port, SCSPTR)->size) {
1909 u16 ctrl = serial_port_in(port, SCSPTR);
1910
1911 /* Active low */
1912 if (state)
1913 ctrl &= ~SCSPTR_RTSDT;
1914 else
1915 ctrl |= SCSPTR_RTSDT;
1916 serial_port_out(port, SCSPTR, ctrl);
1917 }
1918}
1919
1920static bool sci_get_cts(struct uart_port *port)
1921{
1922 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1923 /* Active low */
1924 return !(serial_port_in(port, SCPDR) & SCPDR_CTSD);
1925 } else if (sci_getreg(port, SCSPTR)->size) {
1926 /* Active low */
1927 return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT);
1928 }
1929
1930 return true;
1931}
1932
1933/*
1934 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
1935 * CTS/RTS is supported in hardware by at least one port and controlled
1936 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
1937 * handled via the ->init_pins() op, which is a bit of a one-way street,
1938 * lacking any ability to defer pin control -- this will later be
1939 * converted over to the GPIO framework).
1940 *
1941 * Other modes (such as loopback) are supported generically on certain
1942 * port types, but not others. For these it's sufficient to test for the
1943 * existence of the support register and simply ignore the port type.
1944 */
1945static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
1946{
1947 struct sci_port *s = to_sci_port(port);
1948
1949 if (mctrl & TIOCM_LOOP) {
1950 const struct plat_sci_reg *reg;
1951
1952 /*
1953 * Standard loopback mode for SCFCR ports.
1954 */
1955 reg = sci_getreg(port, SCFCR);
1956 if (reg->size)
1957 serial_port_out(port, SCFCR,
1958 serial_port_in(port, SCFCR) |
1959 SCFCR_LOOP);
1960 }
1961
1962 mctrl_gpio_set(s->gpios, mctrl);
1963
1964 if (!s->has_rtscts)
1965 return;
1966
1967 if (!(mctrl & TIOCM_RTS)) {
1968 /* Disable Auto RTS */
1969 serial_port_out(port, SCFCR,
1970 serial_port_in(port, SCFCR) & ~SCFCR_MCE);
1971
1972 /* Clear RTS */
1973 sci_set_rts(port, 0);
1974 } else if (s->autorts) {
1975 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1976 /* Enable RTS# pin function */
1977 serial_port_out(port, SCPCR,
1978 serial_port_in(port, SCPCR) & ~SCPCR_RTSC);
1979 }
1980
1981 /* Enable Auto RTS */
1982 serial_port_out(port, SCFCR,
1983 serial_port_in(port, SCFCR) | SCFCR_MCE);
1984 } else {
1985 /* Set RTS */
1986 sci_set_rts(port, 1);
1987 }
1988}
1989
1990static unsigned int sci_get_mctrl(struct uart_port *port)
1991{
1992 struct sci_port *s = to_sci_port(port);
1993 struct mctrl_gpios *gpios = s->gpios;
1994 unsigned int mctrl = 0;
1995
1996 mctrl_gpio_get(gpios, &mctrl);
1997
1998 /*
1999 * CTS/RTS is handled in hardware when supported, while nothing
2000 * else is wired up.
2001 */
2002 if (s->autorts) {
2003 if (sci_get_cts(port))
2004 mctrl |= TIOCM_CTS;
2005 } else if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS))) {
2006 mctrl |= TIOCM_CTS;
2007 }
2008 if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR)))
2009 mctrl |= TIOCM_DSR;
2010 if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD)))
2011 mctrl |= TIOCM_CAR;
2012
2013 return mctrl;
2014}
2015
2016static void sci_enable_ms(struct uart_port *port)
2017{
2018 mctrl_gpio_enable_ms(to_sci_port(port)->gpios);
2019}
2020
2021static void sci_break_ctl(struct uart_port *port, int break_state)
2022{
2023 unsigned short scscr, scsptr;
2024 unsigned long flags;
2025
2026 /* check wheter the port has SCSPTR */
2027 if (!sci_getreg(port, SCSPTR)->size) {
2028 /*
2029 * Not supported by hardware. Most parts couple break and rx
2030 * interrupts together, with break detection always enabled.
2031 */
2032 return;
2033 }
2034
2035 spin_lock_irqsave(&port->lock, flags);
2036 scsptr = serial_port_in(port, SCSPTR);
2037 scscr = serial_port_in(port, SCSCR);
2038
2039 if (break_state == -1) {
2040 scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
2041 scscr &= ~SCSCR_TE;
2042 } else {
2043 scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
2044 scscr |= SCSCR_TE;
2045 }
2046
2047 serial_port_out(port, SCSPTR, scsptr);
2048 serial_port_out(port, SCSCR, scscr);
2049 spin_unlock_irqrestore(&port->lock, flags);
2050}
2051
2052static int sci_startup(struct uart_port *port)
2053{
2054 struct sci_port *s = to_sci_port(port);
2055 int ret;
2056
2057 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2058
2059 sci_request_dma(port);
2060
2061 ret = sci_request_irq(s);
2062 if (unlikely(ret < 0)) {
2063 sci_free_dma(port);
2064 return ret;
2065 }
2066
2067 return 0;
2068}
2069
2070static void sci_shutdown(struct uart_port *port)
2071{
2072 struct sci_port *s = to_sci_port(port);
2073 unsigned long flags;
2074 u16 scr;
2075
2076 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
2077
2078 s->autorts = false;
2079 mctrl_gpio_disable_ms(to_sci_port(port)->gpios);
2080
2081 spin_lock_irqsave(&port->lock, flags);
2082 sci_stop_rx(port);
2083 sci_stop_tx(port);
2084 /*
2085 * Stop RX and TX, disable related interrupts, keep clock source
2086 * and HSCIF TOT bits
2087 */
2088 scr = serial_port_in(port, SCSCR);
2089 serial_port_out(port, SCSCR, scr &
2090 (SCSCR_CKE1 | SCSCR_CKE0 | s->hscif_tot));
2091 spin_unlock_irqrestore(&port->lock, flags);
2092
2093#ifdef CONFIG_SERIAL_SH_SCI_DMA
2094 if (s->chan_rx) {
2095 dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__,
2096 port->line);
2097 hrtimer_cancel(&s->rx_timer);
2098 }
2099#endif
2100
2101 sci_free_irq(s);
2102 sci_free_dma(port);
2103}
2104
2105static int sci_sck_calc(struct sci_port *s, unsigned int bps,
2106 unsigned int *srr)
2107{
2108 unsigned long freq = s->clk_rates[SCI_SCK];
2109 int err, min_err = INT_MAX;
2110 unsigned int sr;
2111
2112 if (s->port.type != PORT_HSCIF)
2113 freq *= 2;
2114
2115 for_each_sr(sr, s) {
2116 err = DIV_ROUND_CLOSEST(freq, sr) - bps;
2117 if (abs(err) >= abs(min_err))
2118 continue;
2119
2120 min_err = err;
2121 *srr = sr - 1;
2122
2123 if (!err)
2124 break;
2125 }
2126
2127 dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
2128 *srr + 1);
2129 return min_err;
2130}
2131
2132static int sci_brg_calc(struct sci_port *s, unsigned int bps,
2133 unsigned long freq, unsigned int *dlr,
2134 unsigned int *srr)
2135{
2136 int err, min_err = INT_MAX;
2137 unsigned int sr, dl;
2138
2139 if (s->port.type != PORT_HSCIF)
2140 freq *= 2;
2141
2142 for_each_sr(sr, s) {
2143 dl = DIV_ROUND_CLOSEST(freq, sr * bps);
2144 dl = clamp(dl, 1U, 65535U);
2145
2146 err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
2147 if (abs(err) >= abs(min_err))
2148 continue;
2149
2150 min_err = err;
2151 *dlr = dl;
2152 *srr = sr - 1;
2153
2154 if (!err)
2155 break;
2156 }
2157
2158 dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
2159 min_err, *dlr, *srr + 1);
2160 return min_err;
2161}
2162
2163/* calculate sample rate, BRR, and clock select */
2164static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
2165 unsigned int *brr, unsigned int *srr,
2166 unsigned int *cks)
2167{
2168 unsigned long freq = s->clk_rates[SCI_FCK];
2169 unsigned int sr, br, prediv, scrate, c;
2170 int err, min_err = INT_MAX;
2171
2172 if (s->port.type != PORT_HSCIF)
2173 freq *= 2;
2174
2175 /*
2176 * Find the combination of sample rate and clock select with the
2177 * smallest deviation from the desired baud rate.
2178 * Prefer high sample rates to maximise the receive margin.
2179 *
2180 * M: Receive margin (%)
2181 * N: Ratio of bit rate to clock (N = sampling rate)
2182 * D: Clock duty (D = 0 to 1.0)
2183 * L: Frame length (L = 9 to 12)
2184 * F: Absolute value of clock frequency deviation
2185 *
2186 * M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
2187 * (|D - 0.5| / N * (1 + F))|
2188 * NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
2189 */
2190 for_each_sr(sr, s) {
2191 for (c = 0; c <= 3; c++) {
2192 /* integerized formulas from HSCIF documentation */
2193 prediv = sr * (1 << (2 * c + 1));
2194
2195 /*
2196 * We need to calculate:
2197 *
2198 * br = freq / (prediv * bps) clamped to [1..256]
2199 * err = freq / (br * prediv) - bps
2200 *
2201 * Watch out for overflow when calculating the desired
2202 * sampling clock rate!
2203 */
2204 if (bps > UINT_MAX / prediv)
2205 break;
2206
2207 scrate = prediv * bps;
2208 br = DIV_ROUND_CLOSEST(freq, scrate);
2209 br = clamp(br, 1U, 256U);
2210
2211 err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
2212 if (abs(err) >= abs(min_err))
2213 continue;
2214
2215 min_err = err;
2216 *brr = br - 1;
2217 *srr = sr - 1;
2218 *cks = c;
2219
2220 if (!err)
2221 goto found;
2222 }
2223 }
2224
2225found:
2226 dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
2227 min_err, *brr, *srr + 1, *cks);
2228 return min_err;
2229}
2230
2231static void sci_reset(struct uart_port *port)
2232{
2233 const struct plat_sci_reg *reg;
2234 unsigned int status;
2235 struct sci_port *s = to_sci_port(port);
2236
2237 serial_port_out(port, SCSCR, s->hscif_tot); /* TE=0, RE=0, CKE1=0 */
2238
2239 reg = sci_getreg(port, SCFCR);
2240 if (reg->size)
2241 serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
2242
2243 sci_clear_SCxSR(port,
2244 SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) &
2245 SCxSR_BREAK_CLEAR(port));
2246 if (sci_getreg(port, SCLSR)->size) {
2247 status = serial_port_in(port, SCLSR);
2248 status &= ~(SCLSR_TO | SCLSR_ORER);
2249 serial_port_out(port, SCLSR, status);
2250 }
2251
2252 if (s->rx_trigger > 1) {
2253 if (s->rx_fifo_timeout) {
2254 scif_set_rtrg(port, 1);
2255 timer_setup(&s->rx_fifo_timer, rx_fifo_timer_fn, 0);
2256 } else {
2257 if (port->type == PORT_SCIFA ||
2258 port->type == PORT_SCIFB)
2259 scif_set_rtrg(port, 1);
2260 else
2261 scif_set_rtrg(port, s->rx_trigger);
2262 }
2263 }
2264}
2265
2266static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
2267 struct ktermios *old)
2268{
2269 unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i, bits;
2270 unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
2271 unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
2272 struct sci_port *s = to_sci_port(port);
2273 const struct plat_sci_reg *reg;
2274 int min_err = INT_MAX, err;
2275 unsigned long max_freq = 0;
2276 int best_clk = -1;
2277 unsigned long flags;
2278
2279 if ((termios->c_cflag & CSIZE) == CS7)
2280 smr_val |= SCSMR_CHR;
2281 if (termios->c_cflag & PARENB)
2282 smr_val |= SCSMR_PE;
2283 if (termios->c_cflag & PARODD)
2284 smr_val |= SCSMR_PE | SCSMR_ODD;
2285 if (termios->c_cflag & CSTOPB)
2286 smr_val |= SCSMR_STOP;
2287
2288 /*
2289 * earlyprintk comes here early on with port->uartclk set to zero.
2290 * the clock framework is not up and running at this point so here
2291 * we assume that 115200 is the maximum baud rate. please note that
2292 * the baud rate is not programmed during earlyprintk - it is assumed
2293 * that the previous boot loader has enabled required clocks and
2294 * setup the baud rate generator hardware for us already.
2295 */
2296 if (!port->uartclk) {
2297 baud = uart_get_baud_rate(port, termios, old, 0, 115200);
2298 goto done;
2299 }
2300
2301 for (i = 0; i < SCI_NUM_CLKS; i++)
2302 max_freq = max(max_freq, s->clk_rates[i]);
2303
2304 baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
2305 if (!baud)
2306 goto done;
2307
2308 /*
2309 * There can be multiple sources for the sampling clock. Find the one
2310 * that gives us the smallest deviation from the desired baud rate.
2311 */
2312
2313 /* Optional Undivided External Clock */
2314 if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
2315 port->type != PORT_SCIFB) {
2316 err = sci_sck_calc(s, baud, &srr1);
2317 if (abs(err) < abs(min_err)) {
2318 best_clk = SCI_SCK;
2319 scr_val = SCSCR_CKE1;
2320 sccks = SCCKS_CKS;
2321 min_err = err;
2322 srr = srr1;
2323 if (!err)
2324 goto done;
2325 }
2326 }
2327
2328 /* Optional BRG Frequency Divided External Clock */
2329 if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
2330 err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
2331 &srr1);
2332 if (abs(err) < abs(min_err)) {
2333 best_clk = SCI_SCIF_CLK;
2334 scr_val = SCSCR_CKE1;
2335 sccks = 0;
2336 min_err = err;
2337 dl = dl1;
2338 srr = srr1;
2339 if (!err)
2340 goto done;
2341 }
2342 }
2343
2344 /* Optional BRG Frequency Divided Internal Clock */
2345 if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
2346 err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
2347 &srr1);
2348 if (abs(err) < abs(min_err)) {
2349 best_clk = SCI_BRG_INT;
2350 scr_val = SCSCR_CKE1;
2351 sccks = SCCKS_XIN;
2352 min_err = err;
2353 dl = dl1;
2354 srr = srr1;
2355 if (!min_err)
2356 goto done;
2357 }
2358 }
2359
2360 /* Divided Functional Clock using standard Bit Rate Register */
2361 err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
2362 if (abs(err) < abs(min_err)) {
2363 best_clk = SCI_FCK;
2364 scr_val = 0;
2365 min_err = err;
2366 brr = brr1;
2367 srr = srr1;
2368 cks = cks1;
2369 }
2370
2371done:
2372 if (best_clk >= 0)
2373 dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
2374 s->clks[best_clk], baud, min_err);
2375
2376 sci_port_enable(s);
2377
2378 /*
2379 * Program the optional External Baud Rate Generator (BRG) first.
2380 * It controls the mux to select (H)SCK or frequency divided clock.
2381 */
2382 if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
2383 serial_port_out(port, SCDL, dl);
2384 serial_port_out(port, SCCKS, sccks);
2385 }
2386
2387 spin_lock_irqsave(&port->lock, flags);
2388
2389 sci_reset(port);
2390
2391 uart_update_timeout(port, termios->c_cflag, baud);
2392
2393 if (best_clk >= 0) {
2394 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
2395 switch (srr + 1) {
2396 case 5: smr_val |= SCSMR_SRC_5; break;
2397 case 7: smr_val |= SCSMR_SRC_7; break;
2398 case 11: smr_val |= SCSMR_SRC_11; break;
2399 case 13: smr_val |= SCSMR_SRC_13; break;
2400 case 16: smr_val |= SCSMR_SRC_16; break;
2401 case 17: smr_val |= SCSMR_SRC_17; break;
2402 case 19: smr_val |= SCSMR_SRC_19; break;
2403 case 27: smr_val |= SCSMR_SRC_27; break;
2404 }
2405 smr_val |= cks;
2406 serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2407 serial_port_out(port, SCSMR, smr_val);
2408 serial_port_out(port, SCBRR, brr);
2409 if (sci_getreg(port, HSSRR)->size)
2410 serial_port_out(port, HSSRR, srr | HSCIF_SRE);
2411
2412 /* Wait one bit interval */
2413 udelay((1000000 + (baud - 1)) / baud);
2414 } else {
2415 /* Don't touch the bit rate configuration */
2416 scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
2417 smr_val |= serial_port_in(port, SCSMR) &
2418 (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
2419 serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2420 serial_port_out(port, SCSMR, smr_val);
2421 }
2422
2423 sci_init_pins(port, termios->c_cflag);
2424
2425 port->status &= ~UPSTAT_AUTOCTS;
2426 s->autorts = false;
2427 reg = sci_getreg(port, SCFCR);
2428 if (reg->size) {
2429 unsigned short ctrl = serial_port_in(port, SCFCR);
2430
2431 if ((port->flags & UPF_HARD_FLOW) &&
2432 (termios->c_cflag & CRTSCTS)) {
2433 /* There is no CTS interrupt to restart the hardware */
2434 port->status |= UPSTAT_AUTOCTS;
2435 /* MCE is enabled when RTS is raised */
2436 s->autorts = true;
2437 }
2438
2439 /*
2440 * As we've done a sci_reset() above, ensure we don't
2441 * interfere with the FIFOs while toggling MCE. As the
2442 * reset values could still be set, simply mask them out.
2443 */
2444 ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
2445
2446 serial_port_out(port, SCFCR, ctrl);
2447 }
2448 if (port->flags & UPF_HARD_FLOW) {
2449 /* Refresh (Auto) RTS */
2450 sci_set_mctrl(port, port->mctrl);
2451 }
2452
2453 scr_val |= SCSCR_RE | SCSCR_TE |
2454 (s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0));
2455 serial_port_out(port, SCSCR, scr_val | s->hscif_tot);
2456 if ((srr + 1 == 5) &&
2457 (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
2458 /*
2459 * In asynchronous mode, when the sampling rate is 1/5, first
2460 * received data may become invalid on some SCIFA and SCIFB.
2461 * To avoid this problem wait more than 1 serial data time (1
2462 * bit time x serial data number) after setting SCSCR.RE = 1.
2463 */
2464 udelay(DIV_ROUND_UP(10 * 1000000, baud));
2465 }
2466
2467 /*
2468 * Calculate delay for 2 DMA buffers (4 FIFO).
2469 * See serial_core.c::uart_update_timeout().
2470 * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above
2471 * function calculates 1 jiffie for the data plus 5 jiffies for the
2472 * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA
2473 * buffers (4 FIFO sizes), but when performing a faster transfer, the
2474 * value obtained by this formula is too small. Therefore, if the value
2475 * is smaller than 20ms, use 20ms as the timeout value for DMA.
2476 */
2477 /* byte size and parity */
2478 switch (termios->c_cflag & CSIZE) {
2479 case CS5:
2480 bits = 7;
2481 break;
2482 case CS6:
2483 bits = 8;
2484 break;
2485 case CS7:
2486 bits = 9;
2487 break;
2488 default:
2489 bits = 10;
2490 break;
2491 }
2492
2493 if (termios->c_cflag & CSTOPB)
2494 bits++;
2495 if (termios->c_cflag & PARENB)
2496 bits++;
2497
2498 s->rx_frame = (10000 * bits) / (baud / 100);
2499#ifdef CONFIG_SERIAL_SH_SCI_DMA
2500 s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
2501 if (s->rx_timeout < 20)
2502 s->rx_timeout = 20;
2503#endif
2504
2505 if ((termios->c_cflag & CREAD) != 0)
2506 sci_start_rx(port);
2507
2508 spin_unlock_irqrestore(&port->lock, flags);
2509
2510 sci_port_disable(s);
2511
2512 if (UART_ENABLE_MS(port, termios->c_cflag))
2513 sci_enable_ms(port);
2514}
2515
2516static void sci_pm(struct uart_port *port, unsigned int state,
2517 unsigned int oldstate)
2518{
2519 struct sci_port *sci_port = to_sci_port(port);
2520
2521 switch (state) {
2522 case UART_PM_STATE_OFF:
2523 sci_port_disable(sci_port);
2524 break;
2525 default:
2526 sci_port_enable(sci_port);
2527 break;
2528 }
2529}
2530
2531static const char *sci_type(struct uart_port *port)
2532{
2533 switch (port->type) {
2534 case PORT_IRDA:
2535 return "irda";
2536 case PORT_SCI:
2537 return "sci";
2538 case PORT_SCIF:
2539 return "scif";
2540 case PORT_SCIFA:
2541 return "scifa";
2542 case PORT_SCIFB:
2543 return "scifb";
2544 case PORT_HSCIF:
2545 return "hscif";
2546 }
2547
2548 return NULL;
2549}
2550
2551static int sci_remap_port(struct uart_port *port)
2552{
2553 struct sci_port *sport = to_sci_port(port);
2554
2555 /*
2556 * Nothing to do if there's already an established membase.
2557 */
2558 if (port->membase)
2559 return 0;
2560
2561 if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2562 port->membase = ioremap_nocache(port->mapbase, sport->reg_size);
2563 if (unlikely(!port->membase)) {
2564 dev_err(port->dev, "can't remap port#%d\n", port->line);
2565 return -ENXIO;
2566 }
2567 } else {
2568 /*
2569 * For the simple (and majority of) cases where we don't
2570 * need to do any remapping, just cast the cookie
2571 * directly.
2572 */
2573 port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2574 }
2575
2576 return 0;
2577}
2578
2579static void sci_release_port(struct uart_port *port)
2580{
2581 struct sci_port *sport = to_sci_port(port);
2582
2583 if (port->dev->of_node || (port->flags & UPF_IOREMAP)) {
2584 iounmap(port->membase);
2585 port->membase = NULL;
2586 }
2587
2588 release_mem_region(port->mapbase, sport->reg_size);
2589}
2590
2591static int sci_request_port(struct uart_port *port)
2592{
2593 struct resource *res;
2594 struct sci_port *sport = to_sci_port(port);
2595 int ret;
2596
2597 res = request_mem_region(port->mapbase, sport->reg_size,
2598 dev_name(port->dev));
2599 if (unlikely(res == NULL)) {
2600 dev_err(port->dev, "request_mem_region failed.");
2601 return -EBUSY;
2602 }
2603
2604 ret = sci_remap_port(port);
2605 if (unlikely(ret != 0)) {
2606 release_resource(res);
2607 return ret;
2608 }
2609
2610 return 0;
2611}
2612
2613static void sci_config_port(struct uart_port *port, int flags)
2614{
2615 if (flags & UART_CONFIG_TYPE) {
2616 struct sci_port *sport = to_sci_port(port);
2617
2618 port->type = sport->cfg->type;
2619 sci_request_port(port);
2620 }
2621}
2622
2623static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2624{
2625 if (ser->baud_base < 2400)
2626 /* No paper tape reader for Mitch.. */
2627 return -EINVAL;
2628
2629 return 0;
2630}
2631
2632static const struct uart_ops sci_uart_ops = {
2633 .tx_empty = sci_tx_empty,
2634 .set_mctrl = sci_set_mctrl,
2635 .get_mctrl = sci_get_mctrl,
2636 .start_tx = sci_start_tx,
2637 .stop_tx = sci_stop_tx,
2638 .stop_rx = sci_stop_rx,
2639 .enable_ms = sci_enable_ms,
2640 .break_ctl = sci_break_ctl,
2641 .startup = sci_startup,
2642 .shutdown = sci_shutdown,
2643 .flush_buffer = sci_flush_buffer,
2644 .set_termios = sci_set_termios,
2645 .pm = sci_pm,
2646 .type = sci_type,
2647 .release_port = sci_release_port,
2648 .request_port = sci_request_port,
2649 .config_port = sci_config_port,
2650 .verify_port = sci_verify_port,
2651#ifdef CONFIG_CONSOLE_POLL
2652 .poll_get_char = sci_poll_get_char,
2653 .poll_put_char = sci_poll_put_char,
2654#endif
2655};
2656
2657static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
2658{
2659 const char *clk_names[] = {
2660 [SCI_FCK] = "fck",
2661 [SCI_SCK] = "sck",
2662 [SCI_BRG_INT] = "brg_int",
2663 [SCI_SCIF_CLK] = "scif_clk",
2664 };
2665 struct clk *clk;
2666 unsigned int i;
2667
2668 if (sci_port->cfg->type == PORT_HSCIF)
2669 clk_names[SCI_SCK] = "hsck";
2670
2671 for (i = 0; i < SCI_NUM_CLKS; i++) {
2672 clk = devm_clk_get(dev, clk_names[i]);
2673 if (PTR_ERR(clk) == -EPROBE_DEFER)
2674 return -EPROBE_DEFER;
2675
2676 if (IS_ERR(clk) && i == SCI_FCK) {
2677 /*
2678 * "fck" used to be called "sci_ick", and we need to
2679 * maintain DT backward compatibility.
2680 */
2681 clk = devm_clk_get(dev, "sci_ick");
2682 if (PTR_ERR(clk) == -EPROBE_DEFER)
2683 return -EPROBE_DEFER;
2684
2685 if (!IS_ERR(clk))
2686 goto found;
2687
2688 /*
2689 * Not all SH platforms declare a clock lookup entry
2690 * for SCI devices, in which case we need to get the
2691 * global "peripheral_clk" clock.
2692 */
2693 clk = devm_clk_get(dev, "peripheral_clk");
2694 if (!IS_ERR(clk))
2695 goto found;
2696
2697 dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
2698 PTR_ERR(clk));
2699 return PTR_ERR(clk);
2700 }
2701
2702found:
2703 if (IS_ERR(clk))
2704 dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
2705 PTR_ERR(clk));
2706 else
2707 dev_dbg(dev, "clk %s is %pC rate %pCr\n", clk_names[i],
2708 clk, clk);
2709 sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
2710 }
2711 return 0;
2712}
2713
2714static const struct sci_port_params *
2715sci_probe_regmap(const struct plat_sci_port *cfg)
2716{
2717 unsigned int regtype;
2718
2719 if (cfg->regtype != SCIx_PROBE_REGTYPE)
2720 return &sci_port_params[cfg->regtype];
2721
2722 switch (cfg->type) {
2723 case PORT_SCI:
2724 regtype = SCIx_SCI_REGTYPE;
2725 break;
2726 case PORT_IRDA:
2727 regtype = SCIx_IRDA_REGTYPE;
2728 break;
2729 case PORT_SCIFA:
2730 regtype = SCIx_SCIFA_REGTYPE;
2731 break;
2732 case PORT_SCIFB:
2733 regtype = SCIx_SCIFB_REGTYPE;
2734 break;
2735 case PORT_SCIF:
2736 /*
2737 * The SH-4 is a bit of a misnomer here, although that's
2738 * where this particular port layout originated. This
2739 * configuration (or some slight variation thereof)
2740 * remains the dominant model for all SCIFs.
2741 */
2742 regtype = SCIx_SH4_SCIF_REGTYPE;
2743 break;
2744 case PORT_HSCIF:
2745 regtype = SCIx_HSCIF_REGTYPE;
2746 break;
2747 default:
2748 pr_err("Can't probe register map for given port\n");
2749 return NULL;
2750 }
2751
2752 return &sci_port_params[regtype];
2753}
2754
2755static int sci_init_single(struct platform_device *dev,
2756 struct sci_port *sci_port, unsigned int index,
2757 const struct plat_sci_port *p, bool early)
2758{
2759 struct uart_port *port = &sci_port->port;
2760 const struct resource *res;
2761 unsigned int i;
2762 int ret;
2763
2764 sci_port->cfg = p;
2765
2766 port->ops = &sci_uart_ops;
2767 port->iotype = UPIO_MEM;
2768 port->line = index;
2769
2770 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2771 if (res == NULL)
2772 return -ENOMEM;
2773
2774 port->mapbase = res->start;
2775 sci_port->reg_size = resource_size(res);
2776
2777 for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i)
2778 sci_port->irqs[i] = platform_get_irq(dev, i);
2779
2780 /* The SCI generates several interrupts. They can be muxed together or
2781 * connected to different interrupt lines. In the muxed case only one
2782 * interrupt resource is specified. In the non-muxed case three or four
2783 * interrupt resources are specified, as the BRI interrupt is optional.
2784 */
2785 if (sci_port->irqs[0] < 0)
2786 return -ENXIO;
2787
2788 if (sci_port->irqs[1] < 0) {
2789 sci_port->irqs[1] = sci_port->irqs[0];
2790 sci_port->irqs[2] = sci_port->irqs[0];
2791 sci_port->irqs[3] = sci_port->irqs[0];
2792 }
2793
2794 sci_port->params = sci_probe_regmap(p);
2795 if (unlikely(sci_port->params == NULL))
2796 return -EINVAL;
2797
2798 switch (p->type) {
2799 case PORT_SCIFB:
2800 sci_port->rx_trigger = 48;
2801 break;
2802 case PORT_HSCIF:
2803 sci_port->rx_trigger = 64;
2804 break;
2805 case PORT_SCIFA:
2806 sci_port->rx_trigger = 32;
2807 break;
2808 case PORT_SCIF:
2809 if (p->regtype == SCIx_SH7705_SCIF_REGTYPE)
2810 /* RX triggering not implemented for this IP */
2811 sci_port->rx_trigger = 1;
2812 else
2813 sci_port->rx_trigger = 8;
2814 break;
2815 default:
2816 sci_port->rx_trigger = 1;
2817 break;
2818 }
2819
2820 sci_port->rx_fifo_timeout = 0;
2821 sci_port->hscif_tot = 0;
2822
2823 /* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2824 * match the SoC datasheet, this should be investigated. Let platform
2825 * data override the sampling rate for now.
2826 */
2827 sci_port->sampling_rate_mask = p->sampling_rate
2828 ? SCI_SR(p->sampling_rate)
2829 : sci_port->params->sampling_rate_mask;
2830
2831 if (!early) {
2832 ret = sci_init_clocks(sci_port, &dev->dev);
2833 if (ret < 0)
2834 return ret;
2835
2836 port->dev = &dev->dev;
2837
2838 pm_runtime_enable(&dev->dev);
2839 }
2840
2841 port->type = p->type;
2842 port->flags = UPF_FIXED_PORT | UPF_BOOT_AUTOCONF | p->flags;
2843 port->fifosize = sci_port->params->fifosize;
2844
2845 if (port->type == PORT_SCI) {
2846 if (sci_port->reg_size >= 0x20)
2847 port->regshift = 2;
2848 else
2849 port->regshift = 1;
2850 }
2851
2852 /*
2853 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2854 * for the multi-IRQ ports, which is where we are primarily
2855 * concerned with the shutdown path synchronization.
2856 *
2857 * For the muxed case there's nothing more to do.
2858 */
2859 port->irq = sci_port->irqs[SCIx_RXI_IRQ];
2860 port->irqflags = 0;
2861
2862 port->serial_in = sci_serial_in;
2863 port->serial_out = sci_serial_out;
2864
2865 return 0;
2866}
2867
2868static void sci_cleanup_single(struct sci_port *port)
2869{
2870 pm_runtime_disable(port->port.dev);
2871}
2872
2873#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
2874 defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
2875static void serial_console_putchar(struct uart_port *port, int ch)
2876{
2877 sci_poll_put_char(port, ch);
2878}
2879
2880/*
2881 * Print a string to the serial port trying not to disturb
2882 * any possible real use of the port...
2883 */
2884static void serial_console_write(struct console *co, const char *s,
2885 unsigned count)
2886{
2887 struct sci_port *sci_port = &sci_ports[co->index];
2888 struct uart_port *port = &sci_port->port;
2889 unsigned short bits, ctrl, ctrl_temp;
2890 unsigned long flags;
2891 int locked = 1;
2892
2893 local_irq_save(flags);
2894#if defined(SUPPORT_SYSRQ)
2895 if (port->sysrq)
2896 locked = 0;
2897 else
2898#endif
2899 if (oops_in_progress)
2900 locked = spin_trylock(&port->lock);
2901 else
2902 spin_lock(&port->lock);
2903
2904 /* first save SCSCR then disable interrupts, keep clock source */
2905 ctrl = serial_port_in(port, SCSCR);
2906 ctrl_temp = SCSCR_RE | SCSCR_TE |
2907 (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
2908 (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
2909 serial_port_out(port, SCSCR, ctrl_temp | sci_port->hscif_tot);
2910
2911 uart_console_write(port, s, count, serial_console_putchar);
2912
2913 /* wait until fifo is empty and last bit has been transmitted */
2914 bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
2915 while ((serial_port_in(port, SCxSR) & bits) != bits)
2916 cpu_relax();
2917
2918 /* restore the SCSCR */
2919 serial_port_out(port, SCSCR, ctrl);
2920
2921 if (locked)
2922 spin_unlock(&port->lock);
2923 local_irq_restore(flags);
2924}
2925
2926static int serial_console_setup(struct console *co, char *options)
2927{
2928 struct sci_port *sci_port;
2929 struct uart_port *port;
2930 int baud = 115200;
2931 int bits = 8;
2932 int parity = 'n';
2933 int flow = 'n';
2934 int ret;
2935
2936 /*
2937 * Refuse to handle any bogus ports.
2938 */
2939 if (co->index < 0 || co->index >= SCI_NPORTS)
2940 return -ENODEV;
2941
2942 sci_port = &sci_ports[co->index];
2943 port = &sci_port->port;
2944
2945 /*
2946 * Refuse to handle uninitialized ports.
2947 */
2948 if (!port->ops)
2949 return -ENODEV;
2950
2951 ret = sci_remap_port(port);
2952 if (unlikely(ret != 0))
2953 return ret;
2954
2955 if (options)
2956 uart_parse_options(options, &baud, &parity, &bits, &flow);
2957
2958 return uart_set_options(port, co, baud, parity, bits, flow);
2959}
2960
2961static struct console serial_console = {
2962 .name = "ttySC",
2963 .device = uart_console_device,
2964 .write = serial_console_write,
2965 .setup = serial_console_setup,
2966 .flags = CON_PRINTBUFFER,
2967 .index = -1,
2968 .data = &sci_uart_driver,
2969};
2970
2971static struct console early_serial_console = {
2972 .name = "early_ttySC",
2973 .write = serial_console_write,
2974 .flags = CON_PRINTBUFFER,
2975 .index = -1,
2976};
2977
2978static char early_serial_buf[32];
2979
2980static int sci_probe_earlyprintk(struct platform_device *pdev)
2981{
2982 const struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
2983
2984 if (early_serial_console.data)
2985 return -EEXIST;
2986
2987 early_serial_console.index = pdev->id;
2988
2989 sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
2990
2991 serial_console_setup(&early_serial_console, early_serial_buf);
2992
2993 if (!strstr(early_serial_buf, "keep"))
2994 early_serial_console.flags |= CON_BOOT;
2995
2996 register_console(&early_serial_console);
2997 return 0;
2998}
2999
3000#define SCI_CONSOLE (&serial_console)
3001
3002#else
3003static inline int sci_probe_earlyprintk(struct platform_device *pdev)
3004{
3005 return -EINVAL;
3006}
3007
3008#define SCI_CONSOLE NULL
3009
3010#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
3011
3012static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
3013
3014static DEFINE_MUTEX(sci_uart_registration_lock);
3015static struct uart_driver sci_uart_driver = {
3016 .owner = THIS_MODULE,
3017 .driver_name = "sci",
3018 .dev_name = "ttySC",
3019 .major = SCI_MAJOR,
3020 .minor = SCI_MINOR_START,
3021 .nr = SCI_NPORTS,
3022 .cons = SCI_CONSOLE,
3023};
3024
3025static int sci_remove(struct platform_device *dev)
3026{
3027 struct sci_port *port = platform_get_drvdata(dev);
3028
3029 uart_remove_one_port(&sci_uart_driver, &port->port);
3030
3031 sci_cleanup_single(port);
3032
3033 if (port->port.fifosize > 1) {
3034 sysfs_remove_file(&dev->dev.kobj,
3035 &dev_attr_rx_fifo_trigger.attr);
3036 }
3037 if (port->port.type == PORT_SCIFA || port->port.type == PORT_SCIFB ||
3038 port->port.type == PORT_HSCIF) {
3039 sysfs_remove_file(&dev->dev.kobj,
3040 &dev_attr_rx_fifo_timeout.attr);
3041 }
3042
3043 return 0;
3044}
3045
3046
3047#define SCI_OF_DATA(type, regtype) (void *)((type) << 16 | (regtype))
3048#define SCI_OF_TYPE(data) ((unsigned long)(data) >> 16)
3049#define SCI_OF_REGTYPE(data) ((unsigned long)(data) & 0xffff)
3050
3051static const struct of_device_id of_sci_match[] = {
3052 /* SoC-specific types */
3053 {
3054 .compatible = "renesas,scif-r7s72100",
3055 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
3056 },
3057 /* Family-specific types */
3058 {
3059 .compatible = "renesas,rcar-gen1-scif",
3060 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3061 }, {
3062 .compatible = "renesas,rcar-gen2-scif",
3063 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3064 }, {
3065 .compatible = "renesas,rcar-gen3-scif",
3066 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
3067 },
3068 /* Generic types */
3069 {
3070 .compatible = "renesas,scif",
3071 .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
3072 }, {
3073 .compatible = "renesas,scifa",
3074 .data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
3075 }, {
3076 .compatible = "renesas,scifb",
3077 .data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
3078 }, {
3079 .compatible = "renesas,hscif",
3080 .data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
3081 }, {
3082 .compatible = "renesas,sci",
3083 .data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
3084 }, {
3085 /* Terminator */
3086 },
3087};
3088MODULE_DEVICE_TABLE(of, of_sci_match);
3089
3090static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
3091 unsigned int *dev_id)
3092{
3093 struct device_node *np = pdev->dev.of_node;
3094 struct plat_sci_port *p;
3095 struct sci_port *sp;
3096 const void *data;
3097 int id;
3098
3099 if (!IS_ENABLED(CONFIG_OF) || !np)
3100 return NULL;
3101
3102 data = of_device_get_match_data(&pdev->dev);
3103
3104 p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
3105 if (!p)
3106 return NULL;
3107
3108 /* Get the line number from the aliases node. */
3109 id = of_alias_get_id(np, "serial");
3110 if (id < 0) {
3111 dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
3112 return NULL;
3113 }
3114 if (id >= ARRAY_SIZE(sci_ports)) {
3115 dev_err(&pdev->dev, "serial%d out of range\n", id);
3116 return NULL;
3117 }
3118
3119 sp = &sci_ports[id];
3120 *dev_id = id;
3121
3122 p->type = SCI_OF_TYPE(data);
3123 p->regtype = SCI_OF_REGTYPE(data);
3124
3125 sp->has_rtscts = of_property_read_bool(np, "uart-has-rtscts");
3126
3127 return p;
3128}
3129
3130static int sci_probe_single(struct platform_device *dev,
3131 unsigned int index,
3132 struct plat_sci_port *p,
3133 struct sci_port *sciport)
3134{
3135 int ret;
3136
3137 /* Sanity check */
3138 if (unlikely(index >= SCI_NPORTS)) {
3139 dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
3140 index+1, SCI_NPORTS);
3141 dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
3142 return -EINVAL;
3143 }
3144
3145 mutex_lock(&sci_uart_registration_lock);
3146 if (!sci_uart_driver.state) {
3147 ret = uart_register_driver(&sci_uart_driver);
3148 if (ret) {
3149 mutex_unlock(&sci_uart_registration_lock);
3150 return ret;
3151 }
3152 }
3153 mutex_unlock(&sci_uart_registration_lock);
3154
3155 ret = sci_init_single(dev, sciport, index, p, false);
3156 if (ret)
3157 return ret;
3158
3159 sciport->gpios = mctrl_gpio_init(&sciport->port, 0);
3160 if (IS_ERR(sciport->gpios) && PTR_ERR(sciport->gpios) != -ENOSYS)
3161 return PTR_ERR(sciport->gpios);
3162
3163 if (sciport->has_rtscts) {
3164 if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3165 UART_GPIO_CTS)) ||
3166 !IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios,
3167 UART_GPIO_RTS))) {
3168 dev_err(&dev->dev, "Conflicting RTS/CTS config\n");
3169 return -EINVAL;
3170 }
3171 sciport->port.flags |= UPF_HARD_FLOW;
3172 }
3173
3174 ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
3175 if (ret) {
3176 sci_cleanup_single(sciport);
3177 return ret;
3178 }
3179
3180 return 0;
3181}
3182
3183static int sci_probe(struct platform_device *dev)
3184{
3185 struct plat_sci_port *p;
3186 struct sci_port *sp;
3187 unsigned int dev_id;
3188 int ret;
3189
3190 /*
3191 * If we've come here via earlyprintk initialization, head off to
3192 * the special early probe. We don't have sufficient device state
3193 * to make it beyond this yet.
3194 */
3195 if (is_early_platform_device(dev))
3196 return sci_probe_earlyprintk(dev);
3197
3198 if (dev->dev.of_node) {
3199 p = sci_parse_dt(dev, &dev_id);
3200 if (p == NULL)
3201 return -EINVAL;
3202 } else {
3203 p = dev->dev.platform_data;
3204 if (p == NULL) {
3205 dev_err(&dev->dev, "no platform data supplied\n");
3206 return -EINVAL;
3207 }
3208
3209 dev_id = dev->id;
3210 }
3211
3212 sp = &sci_ports[dev_id];
3213 platform_set_drvdata(dev, sp);
3214
3215 ret = sci_probe_single(dev, dev_id, p, sp);
3216 if (ret)
3217 return ret;
3218
3219 if (sp->port.fifosize > 1) {
3220 ret = sysfs_create_file(&dev->dev.kobj,
3221 &dev_attr_rx_fifo_trigger.attr);
3222 if (ret)
3223 return ret;
3224 }
3225 if (sp->port.type == PORT_SCIFA || sp->port.type == PORT_SCIFB ||
3226 sp->port.type == PORT_HSCIF) {
3227 ret = sysfs_create_file(&dev->dev.kobj,
3228 &dev_attr_rx_fifo_timeout.attr);
3229 if (ret) {
3230 if (sp->port.fifosize > 1) {
3231 sysfs_remove_file(&dev->dev.kobj,
3232 &dev_attr_rx_fifo_trigger.attr);
3233 }
3234 return ret;
3235 }
3236 }
3237
3238#ifdef CONFIG_SH_STANDARD_BIOS
3239 sh_bios_gdb_detach();
3240#endif
3241
3242 return 0;
3243}
3244
3245static __maybe_unused int sci_suspend(struct device *dev)
3246{
3247 struct sci_port *sport = dev_get_drvdata(dev);
3248
3249 if (sport)
3250 uart_suspend_port(&sci_uart_driver, &sport->port);
3251
3252 return 0;
3253}
3254
3255static __maybe_unused int sci_resume(struct device *dev)
3256{
3257 struct sci_port *sport = dev_get_drvdata(dev);
3258
3259 if (sport)
3260 uart_resume_port(&sci_uart_driver, &sport->port);
3261
3262 return 0;
3263}
3264
3265static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume);
3266
3267static struct platform_driver sci_driver = {
3268 .probe = sci_probe,
3269 .remove = sci_remove,
3270 .driver = {
3271 .name = "sh-sci",
3272 .pm = &sci_dev_pm_ops,
3273 .of_match_table = of_match_ptr(of_sci_match),
3274 },
3275};
3276
3277static int __init sci_init(void)
3278{
3279 pr_info("%s\n", banner);
3280
3281 return platform_driver_register(&sci_driver);
3282}
3283
3284static void __exit sci_exit(void)
3285{
3286 platform_driver_unregister(&sci_driver);
3287
3288 if (sci_uart_driver.state)
3289 uart_unregister_driver(&sci_uart_driver);
3290}
3291
3292#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
3293early_platform_init_buffer("earlyprintk", &sci_driver,
3294 early_serial_buf, ARRAY_SIZE(early_serial_buf));
3295#endif
3296#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
3297static struct plat_sci_port port_cfg __initdata;
3298
3299static int __init early_console_setup(struct earlycon_device *device,
3300 int type)
3301{
3302 if (!device->port.membase)
3303 return -ENODEV;
3304
3305 device->port.serial_in = sci_serial_in;
3306 device->port.serial_out = sci_serial_out;
3307 device->port.type = type;
3308 memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
3309 port_cfg.type = type;
3310 sci_ports[0].cfg = &port_cfg;
3311 sci_ports[0].params = sci_probe_regmap(&port_cfg);
3312 port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR);
3313 sci_serial_out(&sci_ports[0].port, SCSCR,
3314 SCSCR_RE | SCSCR_TE | port_cfg.scscr);
3315
3316 device->con->write = serial_console_write;
3317 return 0;
3318}
3319static int __init sci_early_console_setup(struct earlycon_device *device,
3320 const char *opt)
3321{
3322 return early_console_setup(device, PORT_SCI);
3323}
3324static int __init scif_early_console_setup(struct earlycon_device *device,
3325 const char *opt)
3326{
3327 return early_console_setup(device, PORT_SCIF);
3328}
3329static int __init scifa_early_console_setup(struct earlycon_device *device,
3330 const char *opt)
3331{
3332 return early_console_setup(device, PORT_SCIFA);
3333}
3334static int __init scifb_early_console_setup(struct earlycon_device *device,
3335 const char *opt)
3336{
3337 return early_console_setup(device, PORT_SCIFB);
3338}
3339static int __init hscif_early_console_setup(struct earlycon_device *device,
3340 const char *opt)
3341{
3342 return early_console_setup(device, PORT_HSCIF);
3343}
3344
3345OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
3346OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
3347OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
3348OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
3349OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
3350#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
3351
3352module_init(sci_init);
3353module_exit(sci_exit);
3354
3355MODULE_LICENSE("GPL");
3356MODULE_ALIAS("platform:sh-sci");
3357MODULE_AUTHOR("Paul Mundt");
3358MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");
1/*
2 * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
3 *
4 * Copyright (C) 2002 - 2011 Paul Mundt
5 * Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
6 *
7 * based off of the old drivers/char/sh-sci.c by:
8 *
9 * Copyright (C) 1999, 2000 Niibe Yutaka
10 * Copyright (C) 2000 Sugioka Toshinobu
11 * Modified to support multiple serial ports. Stuart Menefy (May 2000).
12 * Modified to support SecureEdge. David McCullough (2002)
13 * Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003).
14 * Removed SH7300 support (Jul 2007).
15 *
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file "COPYING" in the main directory of this archive
18 * for more details.
19 */
20#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
21#define SUPPORT_SYSRQ
22#endif
23
24#undef DEBUG
25
26#include <linux/clk.h>
27#include <linux/console.h>
28#include <linux/ctype.h>
29#include <linux/cpufreq.h>
30#include <linux/delay.h>
31#include <linux/dmaengine.h>
32#include <linux/dma-mapping.h>
33#include <linux/err.h>
34#include <linux/errno.h>
35#include <linux/init.h>
36#include <linux/interrupt.h>
37#include <linux/ioport.h>
38#include <linux/major.h>
39#include <linux/module.h>
40#include <linux/mm.h>
41#include <linux/notifier.h>
42#include <linux/of.h>
43#include <linux/platform_device.h>
44#include <linux/pm_runtime.h>
45#include <linux/scatterlist.h>
46#include <linux/serial.h>
47#include <linux/serial_sci.h>
48#include <linux/sh_dma.h>
49#include <linux/slab.h>
50#include <linux/string.h>
51#include <linux/sysrq.h>
52#include <linux/timer.h>
53#include <linux/tty.h>
54#include <linux/tty_flip.h>
55
56#ifdef CONFIG_SUPERH
57#include <asm/sh_bios.h>
58#endif
59
60#include "sh-sci.h"
61
62/* Offsets into the sci_port->irqs array */
63enum {
64 SCIx_ERI_IRQ,
65 SCIx_RXI_IRQ,
66 SCIx_TXI_IRQ,
67 SCIx_BRI_IRQ,
68 SCIx_NR_IRQS,
69
70 SCIx_MUX_IRQ = SCIx_NR_IRQS, /* special case */
71};
72
73#define SCIx_IRQ_IS_MUXED(port) \
74 ((port)->irqs[SCIx_ERI_IRQ] == \
75 (port)->irqs[SCIx_RXI_IRQ]) || \
76 ((port)->irqs[SCIx_ERI_IRQ] && \
77 ((port)->irqs[SCIx_RXI_IRQ] < 0))
78
79struct sci_port {
80 struct uart_port port;
81
82 /* Platform configuration */
83 struct plat_sci_port *cfg;
84 int overrun_bit;
85 unsigned int error_mask;
86 unsigned int sampling_rate;
87
88
89 /* Break timer */
90 struct timer_list break_timer;
91 int break_flag;
92
93 /* Interface clock */
94 struct clk *iclk;
95 /* Function clock */
96 struct clk *fclk;
97
98 int irqs[SCIx_NR_IRQS];
99 char *irqstr[SCIx_NR_IRQS];
100
101 struct dma_chan *chan_tx;
102 struct dma_chan *chan_rx;
103
104#ifdef CONFIG_SERIAL_SH_SCI_DMA
105 struct dma_async_tx_descriptor *desc_tx;
106 struct dma_async_tx_descriptor *desc_rx[2];
107 dma_cookie_t cookie_tx;
108 dma_cookie_t cookie_rx[2];
109 dma_cookie_t active_rx;
110 struct scatterlist sg_tx;
111 unsigned int sg_len_tx;
112 struct scatterlist sg_rx[2];
113 size_t buf_len_rx;
114 struct sh_dmae_slave param_tx;
115 struct sh_dmae_slave param_rx;
116 struct work_struct work_tx;
117 struct work_struct work_rx;
118 struct timer_list rx_timer;
119 unsigned int rx_timeout;
120#endif
121
122 struct notifier_block freq_transition;
123};
124
125/* Function prototypes */
126static void sci_start_tx(struct uart_port *port);
127static void sci_stop_tx(struct uart_port *port);
128static void sci_start_rx(struct uart_port *port);
129
130#define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS
131
132static struct sci_port sci_ports[SCI_NPORTS];
133static struct uart_driver sci_uart_driver;
134
135static inline struct sci_port *
136to_sci_port(struct uart_port *uart)
137{
138 return container_of(uart, struct sci_port, port);
139}
140
141struct plat_sci_reg {
142 u8 offset, size;
143};
144
145/* Helper for invalidating specific entries of an inherited map. */
146#define sci_reg_invalid { .offset = 0, .size = 0 }
147
148static struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
149 [SCIx_PROBE_REGTYPE] = {
150 [0 ... SCIx_NR_REGS - 1] = sci_reg_invalid,
151 },
152
153 /*
154 * Common SCI definitions, dependent on the port's regshift
155 * value.
156 */
157 [SCIx_SCI_REGTYPE] = {
158 [SCSMR] = { 0x00, 8 },
159 [SCBRR] = { 0x01, 8 },
160 [SCSCR] = { 0x02, 8 },
161 [SCxTDR] = { 0x03, 8 },
162 [SCxSR] = { 0x04, 8 },
163 [SCxRDR] = { 0x05, 8 },
164 [SCFCR] = sci_reg_invalid,
165 [SCFDR] = sci_reg_invalid,
166 [SCTFDR] = sci_reg_invalid,
167 [SCRFDR] = sci_reg_invalid,
168 [SCSPTR] = sci_reg_invalid,
169 [SCLSR] = sci_reg_invalid,
170 [HSSRR] = sci_reg_invalid,
171 },
172
173 /*
174 * Common definitions for legacy IrDA ports, dependent on
175 * regshift value.
176 */
177 [SCIx_IRDA_REGTYPE] = {
178 [SCSMR] = { 0x00, 8 },
179 [SCBRR] = { 0x01, 8 },
180 [SCSCR] = { 0x02, 8 },
181 [SCxTDR] = { 0x03, 8 },
182 [SCxSR] = { 0x04, 8 },
183 [SCxRDR] = { 0x05, 8 },
184 [SCFCR] = { 0x06, 8 },
185 [SCFDR] = { 0x07, 16 },
186 [SCTFDR] = sci_reg_invalid,
187 [SCRFDR] = sci_reg_invalid,
188 [SCSPTR] = sci_reg_invalid,
189 [SCLSR] = sci_reg_invalid,
190 [HSSRR] = sci_reg_invalid,
191 },
192
193 /*
194 * Common SCIFA definitions.
195 */
196 [SCIx_SCIFA_REGTYPE] = {
197 [SCSMR] = { 0x00, 16 },
198 [SCBRR] = { 0x04, 8 },
199 [SCSCR] = { 0x08, 16 },
200 [SCxTDR] = { 0x20, 8 },
201 [SCxSR] = { 0x14, 16 },
202 [SCxRDR] = { 0x24, 8 },
203 [SCFCR] = { 0x18, 16 },
204 [SCFDR] = { 0x1c, 16 },
205 [SCTFDR] = sci_reg_invalid,
206 [SCRFDR] = sci_reg_invalid,
207 [SCSPTR] = sci_reg_invalid,
208 [SCLSR] = sci_reg_invalid,
209 [HSSRR] = sci_reg_invalid,
210 },
211
212 /*
213 * Common SCIFB definitions.
214 */
215 [SCIx_SCIFB_REGTYPE] = {
216 [SCSMR] = { 0x00, 16 },
217 [SCBRR] = { 0x04, 8 },
218 [SCSCR] = { 0x08, 16 },
219 [SCxTDR] = { 0x40, 8 },
220 [SCxSR] = { 0x14, 16 },
221 [SCxRDR] = { 0x60, 8 },
222 [SCFCR] = { 0x18, 16 },
223 [SCFDR] = sci_reg_invalid,
224 [SCTFDR] = { 0x38, 16 },
225 [SCRFDR] = { 0x3c, 16 },
226 [SCSPTR] = sci_reg_invalid,
227 [SCLSR] = sci_reg_invalid,
228 [HSSRR] = sci_reg_invalid,
229 },
230
231 /*
232 * Common SH-2(A) SCIF definitions for ports with FIFO data
233 * count registers.
234 */
235 [SCIx_SH2_SCIF_FIFODATA_REGTYPE] = {
236 [SCSMR] = { 0x00, 16 },
237 [SCBRR] = { 0x04, 8 },
238 [SCSCR] = { 0x08, 16 },
239 [SCxTDR] = { 0x0c, 8 },
240 [SCxSR] = { 0x10, 16 },
241 [SCxRDR] = { 0x14, 8 },
242 [SCFCR] = { 0x18, 16 },
243 [SCFDR] = { 0x1c, 16 },
244 [SCTFDR] = sci_reg_invalid,
245 [SCRFDR] = sci_reg_invalid,
246 [SCSPTR] = { 0x20, 16 },
247 [SCLSR] = { 0x24, 16 },
248 [HSSRR] = sci_reg_invalid,
249 },
250
251 /*
252 * Common SH-3 SCIF definitions.
253 */
254 [SCIx_SH3_SCIF_REGTYPE] = {
255 [SCSMR] = { 0x00, 8 },
256 [SCBRR] = { 0x02, 8 },
257 [SCSCR] = { 0x04, 8 },
258 [SCxTDR] = { 0x06, 8 },
259 [SCxSR] = { 0x08, 16 },
260 [SCxRDR] = { 0x0a, 8 },
261 [SCFCR] = { 0x0c, 8 },
262 [SCFDR] = { 0x0e, 16 },
263 [SCTFDR] = sci_reg_invalid,
264 [SCRFDR] = sci_reg_invalid,
265 [SCSPTR] = sci_reg_invalid,
266 [SCLSR] = sci_reg_invalid,
267 [HSSRR] = sci_reg_invalid,
268 },
269
270 /*
271 * Common SH-4(A) SCIF(B) definitions.
272 */
273 [SCIx_SH4_SCIF_REGTYPE] = {
274 [SCSMR] = { 0x00, 16 },
275 [SCBRR] = { 0x04, 8 },
276 [SCSCR] = { 0x08, 16 },
277 [SCxTDR] = { 0x0c, 8 },
278 [SCxSR] = { 0x10, 16 },
279 [SCxRDR] = { 0x14, 8 },
280 [SCFCR] = { 0x18, 16 },
281 [SCFDR] = { 0x1c, 16 },
282 [SCTFDR] = sci_reg_invalid,
283 [SCRFDR] = sci_reg_invalid,
284 [SCSPTR] = { 0x20, 16 },
285 [SCLSR] = { 0x24, 16 },
286 [HSSRR] = sci_reg_invalid,
287 },
288
289 /*
290 * Common HSCIF definitions.
291 */
292 [SCIx_HSCIF_REGTYPE] = {
293 [SCSMR] = { 0x00, 16 },
294 [SCBRR] = { 0x04, 8 },
295 [SCSCR] = { 0x08, 16 },
296 [SCxTDR] = { 0x0c, 8 },
297 [SCxSR] = { 0x10, 16 },
298 [SCxRDR] = { 0x14, 8 },
299 [SCFCR] = { 0x18, 16 },
300 [SCFDR] = { 0x1c, 16 },
301 [SCTFDR] = sci_reg_invalid,
302 [SCRFDR] = sci_reg_invalid,
303 [SCSPTR] = { 0x20, 16 },
304 [SCLSR] = { 0x24, 16 },
305 [HSSRR] = { 0x40, 16 },
306 },
307
308 /*
309 * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR
310 * register.
311 */
312 [SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = {
313 [SCSMR] = { 0x00, 16 },
314 [SCBRR] = { 0x04, 8 },
315 [SCSCR] = { 0x08, 16 },
316 [SCxTDR] = { 0x0c, 8 },
317 [SCxSR] = { 0x10, 16 },
318 [SCxRDR] = { 0x14, 8 },
319 [SCFCR] = { 0x18, 16 },
320 [SCFDR] = { 0x1c, 16 },
321 [SCTFDR] = sci_reg_invalid,
322 [SCRFDR] = sci_reg_invalid,
323 [SCSPTR] = sci_reg_invalid,
324 [SCLSR] = { 0x24, 16 },
325 [HSSRR] = sci_reg_invalid,
326 },
327
328 /*
329 * Common SH-4(A) SCIF(B) definitions for ports with FIFO data
330 * count registers.
331 */
332 [SCIx_SH4_SCIF_FIFODATA_REGTYPE] = {
333 [SCSMR] = { 0x00, 16 },
334 [SCBRR] = { 0x04, 8 },
335 [SCSCR] = { 0x08, 16 },
336 [SCxTDR] = { 0x0c, 8 },
337 [SCxSR] = { 0x10, 16 },
338 [SCxRDR] = { 0x14, 8 },
339 [SCFCR] = { 0x18, 16 },
340 [SCFDR] = { 0x1c, 16 },
341 [SCTFDR] = { 0x1c, 16 }, /* aliased to SCFDR */
342 [SCRFDR] = { 0x20, 16 },
343 [SCSPTR] = { 0x24, 16 },
344 [SCLSR] = { 0x28, 16 },
345 [HSSRR] = sci_reg_invalid,
346 },
347
348 /*
349 * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR
350 * registers.
351 */
352 [SCIx_SH7705_SCIF_REGTYPE] = {
353 [SCSMR] = { 0x00, 16 },
354 [SCBRR] = { 0x04, 8 },
355 [SCSCR] = { 0x08, 16 },
356 [SCxTDR] = { 0x20, 8 },
357 [SCxSR] = { 0x14, 16 },
358 [SCxRDR] = { 0x24, 8 },
359 [SCFCR] = { 0x18, 16 },
360 [SCFDR] = { 0x1c, 16 },
361 [SCTFDR] = sci_reg_invalid,
362 [SCRFDR] = sci_reg_invalid,
363 [SCSPTR] = sci_reg_invalid,
364 [SCLSR] = sci_reg_invalid,
365 [HSSRR] = sci_reg_invalid,
366 },
367};
368
369#define sci_getreg(up, offset) (sci_regmap[to_sci_port(up)->cfg->regtype] + offset)
370
371/*
372 * The "offset" here is rather misleading, in that it refers to an enum
373 * value relative to the port mapping rather than the fixed offset
374 * itself, which needs to be manually retrieved from the platform's
375 * register map for the given port.
376 */
377static unsigned int sci_serial_in(struct uart_port *p, int offset)
378{
379 struct plat_sci_reg *reg = sci_getreg(p, offset);
380
381 if (reg->size == 8)
382 return ioread8(p->membase + (reg->offset << p->regshift));
383 else if (reg->size == 16)
384 return ioread16(p->membase + (reg->offset << p->regshift));
385 else
386 WARN(1, "Invalid register access\n");
387
388 return 0;
389}
390
391static void sci_serial_out(struct uart_port *p, int offset, int value)
392{
393 struct plat_sci_reg *reg = sci_getreg(p, offset);
394
395 if (reg->size == 8)
396 iowrite8(value, p->membase + (reg->offset << p->regshift));
397 else if (reg->size == 16)
398 iowrite16(value, p->membase + (reg->offset << p->regshift));
399 else
400 WARN(1, "Invalid register access\n");
401}
402
403static int sci_probe_regmap(struct plat_sci_port *cfg)
404{
405 switch (cfg->type) {
406 case PORT_SCI:
407 cfg->regtype = SCIx_SCI_REGTYPE;
408 break;
409 case PORT_IRDA:
410 cfg->regtype = SCIx_IRDA_REGTYPE;
411 break;
412 case PORT_SCIFA:
413 cfg->regtype = SCIx_SCIFA_REGTYPE;
414 break;
415 case PORT_SCIFB:
416 cfg->regtype = SCIx_SCIFB_REGTYPE;
417 break;
418 case PORT_SCIF:
419 /*
420 * The SH-4 is a bit of a misnomer here, although that's
421 * where this particular port layout originated. This
422 * configuration (or some slight variation thereof)
423 * remains the dominant model for all SCIFs.
424 */
425 cfg->regtype = SCIx_SH4_SCIF_REGTYPE;
426 break;
427 case PORT_HSCIF:
428 cfg->regtype = SCIx_HSCIF_REGTYPE;
429 break;
430 default:
431 pr_err("Can't probe register map for given port\n");
432 return -EINVAL;
433 }
434
435 return 0;
436}
437
438static void sci_port_enable(struct sci_port *sci_port)
439{
440 if (!sci_port->port.dev)
441 return;
442
443 pm_runtime_get_sync(sci_port->port.dev);
444
445 clk_prepare_enable(sci_port->iclk);
446 sci_port->port.uartclk = clk_get_rate(sci_port->iclk);
447 clk_prepare_enable(sci_port->fclk);
448}
449
450static void sci_port_disable(struct sci_port *sci_port)
451{
452 if (!sci_port->port.dev)
453 return;
454
455 /* Cancel the break timer to ensure that the timer handler will not try
456 * to access the hardware with clocks and power disabled. Reset the
457 * break flag to make the break debouncing state machine ready for the
458 * next break.
459 */
460 del_timer_sync(&sci_port->break_timer);
461 sci_port->break_flag = 0;
462
463 clk_disable_unprepare(sci_port->fclk);
464 clk_disable_unprepare(sci_port->iclk);
465
466 pm_runtime_put_sync(sci_port->port.dev);
467}
468
469#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
470
471#ifdef CONFIG_CONSOLE_POLL
472static int sci_poll_get_char(struct uart_port *port)
473{
474 unsigned short status;
475 int c;
476
477 do {
478 status = serial_port_in(port, SCxSR);
479 if (status & SCxSR_ERRORS(port)) {
480 serial_port_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
481 continue;
482 }
483 break;
484 } while (1);
485
486 if (!(status & SCxSR_RDxF(port)))
487 return NO_POLL_CHAR;
488
489 c = serial_port_in(port, SCxRDR);
490
491 /* Dummy read */
492 serial_port_in(port, SCxSR);
493 serial_port_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
494
495 return c;
496}
497#endif
498
499static void sci_poll_put_char(struct uart_port *port, unsigned char c)
500{
501 unsigned short status;
502
503 do {
504 status = serial_port_in(port, SCxSR);
505 } while (!(status & SCxSR_TDxE(port)));
506
507 serial_port_out(port, SCxTDR, c);
508 serial_port_out(port, SCxSR, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
509}
510#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */
511
512static void sci_init_pins(struct uart_port *port, unsigned int cflag)
513{
514 struct sci_port *s = to_sci_port(port);
515 struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + SCSPTR;
516
517 /*
518 * Use port-specific handler if provided.
519 */
520 if (s->cfg->ops && s->cfg->ops->init_pins) {
521 s->cfg->ops->init_pins(port, cflag);
522 return;
523 }
524
525 /*
526 * For the generic path SCSPTR is necessary. Bail out if that's
527 * unavailable, too.
528 */
529 if (!reg->size)
530 return;
531
532 if ((s->cfg->capabilities & SCIx_HAVE_RTSCTS) &&
533 ((!(cflag & CRTSCTS)))) {
534 unsigned short status;
535
536 status = serial_port_in(port, SCSPTR);
537 status &= ~SCSPTR_CTSIO;
538 status |= SCSPTR_RTSIO;
539 serial_port_out(port, SCSPTR, status); /* Set RTS = 1 */
540 }
541}
542
543static int sci_txfill(struct uart_port *port)
544{
545 struct plat_sci_reg *reg;
546
547 reg = sci_getreg(port, SCTFDR);
548 if (reg->size)
549 return serial_port_in(port, SCTFDR) & ((port->fifosize << 1) - 1);
550
551 reg = sci_getreg(port, SCFDR);
552 if (reg->size)
553 return serial_port_in(port, SCFDR) >> 8;
554
555 return !(serial_port_in(port, SCxSR) & SCI_TDRE);
556}
557
558static int sci_txroom(struct uart_port *port)
559{
560 return port->fifosize - sci_txfill(port);
561}
562
563static int sci_rxfill(struct uart_port *port)
564{
565 struct plat_sci_reg *reg;
566
567 reg = sci_getreg(port, SCRFDR);
568 if (reg->size)
569 return serial_port_in(port, SCRFDR) & ((port->fifosize << 1) - 1);
570
571 reg = sci_getreg(port, SCFDR);
572 if (reg->size)
573 return serial_port_in(port, SCFDR) & ((port->fifosize << 1) - 1);
574
575 return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0;
576}
577
578/*
579 * SCI helper for checking the state of the muxed port/RXD pins.
580 */
581static inline int sci_rxd_in(struct uart_port *port)
582{
583 struct sci_port *s = to_sci_port(port);
584
585 if (s->cfg->port_reg <= 0)
586 return 1;
587
588 /* Cast for ARM damage */
589 return !!__raw_readb((void __iomem *)(uintptr_t)s->cfg->port_reg);
590}
591
592/* ********************************************************************** *
593 * the interrupt related routines *
594 * ********************************************************************** */
595
596static void sci_transmit_chars(struct uart_port *port)
597{
598 struct circ_buf *xmit = &port->state->xmit;
599 unsigned int stopped = uart_tx_stopped(port);
600 unsigned short status;
601 unsigned short ctrl;
602 int count;
603
604 status = serial_port_in(port, SCxSR);
605 if (!(status & SCxSR_TDxE(port))) {
606 ctrl = serial_port_in(port, SCSCR);
607 if (uart_circ_empty(xmit))
608 ctrl &= ~SCSCR_TIE;
609 else
610 ctrl |= SCSCR_TIE;
611 serial_port_out(port, SCSCR, ctrl);
612 return;
613 }
614
615 count = sci_txroom(port);
616
617 do {
618 unsigned char c;
619
620 if (port->x_char) {
621 c = port->x_char;
622 port->x_char = 0;
623 } else if (!uart_circ_empty(xmit) && !stopped) {
624 c = xmit->buf[xmit->tail];
625 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
626 } else {
627 break;
628 }
629
630 serial_port_out(port, SCxTDR, c);
631
632 port->icount.tx++;
633 } while (--count > 0);
634
635 serial_port_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
636
637 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
638 uart_write_wakeup(port);
639 if (uart_circ_empty(xmit)) {
640 sci_stop_tx(port);
641 } else {
642 ctrl = serial_port_in(port, SCSCR);
643
644 if (port->type != PORT_SCI) {
645 serial_port_in(port, SCxSR); /* Dummy read */
646 serial_port_out(port, SCxSR, SCxSR_TDxE_CLEAR(port));
647 }
648
649 ctrl |= SCSCR_TIE;
650 serial_port_out(port, SCSCR, ctrl);
651 }
652}
653
654/* On SH3, SCIF may read end-of-break as a space->mark char */
655#define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); })
656
657static void sci_receive_chars(struct uart_port *port)
658{
659 struct sci_port *sci_port = to_sci_port(port);
660 struct tty_port *tport = &port->state->port;
661 int i, count, copied = 0;
662 unsigned short status;
663 unsigned char flag;
664
665 status = serial_port_in(port, SCxSR);
666 if (!(status & SCxSR_RDxF(port)))
667 return;
668
669 while (1) {
670 /* Don't copy more bytes than there is room for in the buffer */
671 count = tty_buffer_request_room(tport, sci_rxfill(port));
672
673 /* If for any reason we can't copy more data, we're done! */
674 if (count == 0)
675 break;
676
677 if (port->type == PORT_SCI) {
678 char c = serial_port_in(port, SCxRDR);
679 if (uart_handle_sysrq_char(port, c) ||
680 sci_port->break_flag)
681 count = 0;
682 else
683 tty_insert_flip_char(tport, c, TTY_NORMAL);
684 } else {
685 for (i = 0; i < count; i++) {
686 char c = serial_port_in(port, SCxRDR);
687
688 status = serial_port_in(port, SCxSR);
689#if defined(CONFIG_CPU_SH3)
690 /* Skip "chars" during break */
691 if (sci_port->break_flag) {
692 if ((c == 0) &&
693 (status & SCxSR_FER(port))) {
694 count--; i--;
695 continue;
696 }
697
698 /* Nonzero => end-of-break */
699 dev_dbg(port->dev, "debounce<%02x>\n", c);
700 sci_port->break_flag = 0;
701
702 if (STEPFN(c)) {
703 count--; i--;
704 continue;
705 }
706 }
707#endif /* CONFIG_CPU_SH3 */
708 if (uart_handle_sysrq_char(port, c)) {
709 count--; i--;
710 continue;
711 }
712
713 /* Store data and status */
714 if (status & SCxSR_FER(port)) {
715 flag = TTY_FRAME;
716 port->icount.frame++;
717 dev_notice(port->dev, "frame error\n");
718 } else if (status & SCxSR_PER(port)) {
719 flag = TTY_PARITY;
720 port->icount.parity++;
721 dev_notice(port->dev, "parity error\n");
722 } else
723 flag = TTY_NORMAL;
724
725 tty_insert_flip_char(tport, c, flag);
726 }
727 }
728
729 serial_port_in(port, SCxSR); /* dummy read */
730 serial_port_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
731
732 copied += count;
733 port->icount.rx += count;
734 }
735
736 if (copied) {
737 /* Tell the rest of the system the news. New characters! */
738 tty_flip_buffer_push(tport);
739 } else {
740 serial_port_in(port, SCxSR); /* dummy read */
741 serial_port_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
742 }
743}
744
745#define SCI_BREAK_JIFFIES (HZ/20)
746
747/*
748 * The sci generates interrupts during the break,
749 * 1 per millisecond or so during the break period, for 9600 baud.
750 * So dont bother disabling interrupts.
751 * But dont want more than 1 break event.
752 * Use a kernel timer to periodically poll the rx line until
753 * the break is finished.
754 */
755static inline void sci_schedule_break_timer(struct sci_port *port)
756{
757 mod_timer(&port->break_timer, jiffies + SCI_BREAK_JIFFIES);
758}
759
760/* Ensure that two consecutive samples find the break over. */
761static void sci_break_timer(unsigned long data)
762{
763 struct sci_port *port = (struct sci_port *)data;
764
765 if (sci_rxd_in(&port->port) == 0) {
766 port->break_flag = 1;
767 sci_schedule_break_timer(port);
768 } else if (port->break_flag == 1) {
769 /* break is over. */
770 port->break_flag = 2;
771 sci_schedule_break_timer(port);
772 } else
773 port->break_flag = 0;
774}
775
776static int sci_handle_errors(struct uart_port *port)
777{
778 int copied = 0;
779 unsigned short status = serial_port_in(port, SCxSR);
780 struct tty_port *tport = &port->state->port;
781 struct sci_port *s = to_sci_port(port);
782
783 /* Handle overruns */
784 if (status & (1 << s->overrun_bit)) {
785 port->icount.overrun++;
786
787 /* overrun error */
788 if (tty_insert_flip_char(tport, 0, TTY_OVERRUN))
789 copied++;
790
791 dev_notice(port->dev, "overrun error\n");
792 }
793
794 if (status & SCxSR_FER(port)) {
795 if (sci_rxd_in(port) == 0) {
796 /* Notify of BREAK */
797 struct sci_port *sci_port = to_sci_port(port);
798
799 if (!sci_port->break_flag) {
800 port->icount.brk++;
801
802 sci_port->break_flag = 1;
803 sci_schedule_break_timer(sci_port);
804
805 /* Do sysrq handling. */
806 if (uart_handle_break(port))
807 return 0;
808
809 dev_dbg(port->dev, "BREAK detected\n");
810
811 if (tty_insert_flip_char(tport, 0, TTY_BREAK))
812 copied++;
813 }
814
815 } else {
816 /* frame error */
817 port->icount.frame++;
818
819 if (tty_insert_flip_char(tport, 0, TTY_FRAME))
820 copied++;
821
822 dev_notice(port->dev, "frame error\n");
823 }
824 }
825
826 if (status & SCxSR_PER(port)) {
827 /* parity error */
828 port->icount.parity++;
829
830 if (tty_insert_flip_char(tport, 0, TTY_PARITY))
831 copied++;
832
833 dev_notice(port->dev, "parity error\n");
834 }
835
836 if (copied)
837 tty_flip_buffer_push(tport);
838
839 return copied;
840}
841
842static int sci_handle_fifo_overrun(struct uart_port *port)
843{
844 struct tty_port *tport = &port->state->port;
845 struct sci_port *s = to_sci_port(port);
846 struct plat_sci_reg *reg;
847 int copied = 0;
848
849 reg = sci_getreg(port, SCLSR);
850 if (!reg->size)
851 return 0;
852
853 if ((serial_port_in(port, SCLSR) & (1 << s->overrun_bit))) {
854 serial_port_out(port, SCLSR, 0);
855
856 port->icount.overrun++;
857
858 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
859 tty_flip_buffer_push(tport);
860
861 dev_notice(port->dev, "overrun error\n");
862 copied++;
863 }
864
865 return copied;
866}
867
868static int sci_handle_breaks(struct uart_port *port)
869{
870 int copied = 0;
871 unsigned short status = serial_port_in(port, SCxSR);
872 struct tty_port *tport = &port->state->port;
873 struct sci_port *s = to_sci_port(port);
874
875 if (uart_handle_break(port))
876 return 0;
877
878 if (!s->break_flag && status & SCxSR_BRK(port)) {
879#if defined(CONFIG_CPU_SH3)
880 /* Debounce break */
881 s->break_flag = 1;
882#endif
883
884 port->icount.brk++;
885
886 /* Notify of BREAK */
887 if (tty_insert_flip_char(tport, 0, TTY_BREAK))
888 copied++;
889
890 dev_dbg(port->dev, "BREAK detected\n");
891 }
892
893 if (copied)
894 tty_flip_buffer_push(tport);
895
896 copied += sci_handle_fifo_overrun(port);
897
898 return copied;
899}
900
901static irqreturn_t sci_rx_interrupt(int irq, void *ptr)
902{
903#ifdef CONFIG_SERIAL_SH_SCI_DMA
904 struct uart_port *port = ptr;
905 struct sci_port *s = to_sci_port(port);
906
907 if (s->chan_rx) {
908 u16 scr = serial_port_in(port, SCSCR);
909 u16 ssr = serial_port_in(port, SCxSR);
910
911 /* Disable future Rx interrupts */
912 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
913 disable_irq_nosync(irq);
914 scr |= SCSCR_RDRQE;
915 } else {
916 scr &= ~SCSCR_RIE;
917 }
918 serial_port_out(port, SCSCR, scr);
919 /* Clear current interrupt */
920 serial_port_out(port, SCxSR, ssr & ~(1 | SCxSR_RDxF(port)));
921 dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n",
922 jiffies, s->rx_timeout);
923 mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
924
925 return IRQ_HANDLED;
926 }
927#endif
928
929 /* I think sci_receive_chars has to be called irrespective
930 * of whether the I_IXOFF is set, otherwise, how is the interrupt
931 * to be disabled?
932 */
933 sci_receive_chars(ptr);
934
935 return IRQ_HANDLED;
936}
937
938static irqreturn_t sci_tx_interrupt(int irq, void *ptr)
939{
940 struct uart_port *port = ptr;
941 unsigned long flags;
942
943 spin_lock_irqsave(&port->lock, flags);
944 sci_transmit_chars(port);
945 spin_unlock_irqrestore(&port->lock, flags);
946
947 return IRQ_HANDLED;
948}
949
950static irqreturn_t sci_er_interrupt(int irq, void *ptr)
951{
952 struct uart_port *port = ptr;
953
954 /* Handle errors */
955 if (port->type == PORT_SCI) {
956 if (sci_handle_errors(port)) {
957 /* discard character in rx buffer */
958 serial_port_in(port, SCxSR);
959 serial_port_out(port, SCxSR, SCxSR_RDxF_CLEAR(port));
960 }
961 } else {
962 sci_handle_fifo_overrun(port);
963 sci_rx_interrupt(irq, ptr);
964 }
965
966 serial_port_out(port, SCxSR, SCxSR_ERROR_CLEAR(port));
967
968 /* Kick the transmission */
969 sci_tx_interrupt(irq, ptr);
970
971 return IRQ_HANDLED;
972}
973
974static irqreturn_t sci_br_interrupt(int irq, void *ptr)
975{
976 struct uart_port *port = ptr;
977
978 /* Handle BREAKs */
979 sci_handle_breaks(port);
980 serial_port_out(port, SCxSR, SCxSR_BREAK_CLEAR(port));
981
982 return IRQ_HANDLED;
983}
984
985static inline unsigned long port_rx_irq_mask(struct uart_port *port)
986{
987 /*
988 * Not all ports (such as SCIFA) will support REIE. Rather than
989 * special-casing the port type, we check the port initialization
990 * IRQ enable mask to see whether the IRQ is desired at all. If
991 * it's unset, it's logically inferred that there's no point in
992 * testing for it.
993 */
994 return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE);
995}
996
997static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr)
998{
999 unsigned short ssr_status, scr_status, err_enabled;
1000 struct uart_port *port = ptr;
1001 struct sci_port *s = to_sci_port(port);
1002 irqreturn_t ret = IRQ_NONE;
1003
1004 ssr_status = serial_port_in(port, SCxSR);
1005 scr_status = serial_port_in(port, SCSCR);
1006 err_enabled = scr_status & port_rx_irq_mask(port);
1007
1008 /* Tx Interrupt */
1009 if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) &&
1010 !s->chan_tx)
1011 ret = sci_tx_interrupt(irq, ptr);
1012
1013 /*
1014 * Rx Interrupt: if we're using DMA, the DMA controller clears RDF /
1015 * DR flags
1016 */
1017 if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) &&
1018 (scr_status & SCSCR_RIE))
1019 ret = sci_rx_interrupt(irq, ptr);
1020
1021 /* Error Interrupt */
1022 if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled)
1023 ret = sci_er_interrupt(irq, ptr);
1024
1025 /* Break Interrupt */
1026 if ((ssr_status & SCxSR_BRK(port)) && err_enabled)
1027 ret = sci_br_interrupt(irq, ptr);
1028
1029 return ret;
1030}
1031
1032/*
1033 * Here we define a transition notifier so that we can update all of our
1034 * ports' baud rate when the peripheral clock changes.
1035 */
1036static int sci_notifier(struct notifier_block *self,
1037 unsigned long phase, void *p)
1038{
1039 struct sci_port *sci_port;
1040 unsigned long flags;
1041
1042 sci_port = container_of(self, struct sci_port, freq_transition);
1043
1044 if (phase == CPUFREQ_POSTCHANGE) {
1045 struct uart_port *port = &sci_port->port;
1046
1047 spin_lock_irqsave(&port->lock, flags);
1048 port->uartclk = clk_get_rate(sci_port->iclk);
1049 spin_unlock_irqrestore(&port->lock, flags);
1050 }
1051
1052 return NOTIFY_OK;
1053}
1054
1055static struct sci_irq_desc {
1056 const char *desc;
1057 irq_handler_t handler;
1058} sci_irq_desc[] = {
1059 /*
1060 * Split out handlers, the default case.
1061 */
1062 [SCIx_ERI_IRQ] = {
1063 .desc = "rx err",
1064 .handler = sci_er_interrupt,
1065 },
1066
1067 [SCIx_RXI_IRQ] = {
1068 .desc = "rx full",
1069 .handler = sci_rx_interrupt,
1070 },
1071
1072 [SCIx_TXI_IRQ] = {
1073 .desc = "tx empty",
1074 .handler = sci_tx_interrupt,
1075 },
1076
1077 [SCIx_BRI_IRQ] = {
1078 .desc = "break",
1079 .handler = sci_br_interrupt,
1080 },
1081
1082 /*
1083 * Special muxed handler.
1084 */
1085 [SCIx_MUX_IRQ] = {
1086 .desc = "mux",
1087 .handler = sci_mpxed_interrupt,
1088 },
1089};
1090
1091static int sci_request_irq(struct sci_port *port)
1092{
1093 struct uart_port *up = &port->port;
1094 int i, j, ret = 0;
1095
1096 for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) {
1097 struct sci_irq_desc *desc;
1098 int irq;
1099
1100 if (SCIx_IRQ_IS_MUXED(port)) {
1101 i = SCIx_MUX_IRQ;
1102 irq = up->irq;
1103 } else {
1104 irq = port->irqs[i];
1105
1106 /*
1107 * Certain port types won't support all of the
1108 * available interrupt sources.
1109 */
1110 if (unlikely(irq < 0))
1111 continue;
1112 }
1113
1114 desc = sci_irq_desc + i;
1115 port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s",
1116 dev_name(up->dev), desc->desc);
1117 if (!port->irqstr[j]) {
1118 dev_err(up->dev, "Failed to allocate %s IRQ string\n",
1119 desc->desc);
1120 goto out_nomem;
1121 }
1122
1123 ret = request_irq(irq, desc->handler, up->irqflags,
1124 port->irqstr[j], port);
1125 if (unlikely(ret)) {
1126 dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc);
1127 goto out_noirq;
1128 }
1129 }
1130
1131 return 0;
1132
1133out_noirq:
1134 while (--i >= 0)
1135 free_irq(port->irqs[i], port);
1136
1137out_nomem:
1138 while (--j >= 0)
1139 kfree(port->irqstr[j]);
1140
1141 return ret;
1142}
1143
1144static void sci_free_irq(struct sci_port *port)
1145{
1146 int i;
1147
1148 /*
1149 * Intentionally in reverse order so we iterate over the muxed
1150 * IRQ first.
1151 */
1152 for (i = 0; i < SCIx_NR_IRQS; i++) {
1153 int irq = port->irqs[i];
1154
1155 /*
1156 * Certain port types won't support all of the available
1157 * interrupt sources.
1158 */
1159 if (unlikely(irq < 0))
1160 continue;
1161
1162 free_irq(port->irqs[i], port);
1163 kfree(port->irqstr[i]);
1164
1165 if (SCIx_IRQ_IS_MUXED(port)) {
1166 /* If there's only one IRQ, we're done. */
1167 return;
1168 }
1169 }
1170}
1171
1172static unsigned int sci_tx_empty(struct uart_port *port)
1173{
1174 unsigned short status = serial_port_in(port, SCxSR);
1175 unsigned short in_tx_fifo = sci_txfill(port);
1176
1177 return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0;
1178}
1179
1180/*
1181 * Modem control is a bit of a mixed bag for SCI(F) ports. Generally
1182 * CTS/RTS is supported in hardware by at least one port and controlled
1183 * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently
1184 * handled via the ->init_pins() op, which is a bit of a one-way street,
1185 * lacking any ability to defer pin control -- this will later be
1186 * converted over to the GPIO framework).
1187 *
1188 * Other modes (such as loopback) are supported generically on certain
1189 * port types, but not others. For these it's sufficient to test for the
1190 * existence of the support register and simply ignore the port type.
1191 */
1192static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl)
1193{
1194 if (mctrl & TIOCM_LOOP) {
1195 struct plat_sci_reg *reg;
1196
1197 /*
1198 * Standard loopback mode for SCFCR ports.
1199 */
1200 reg = sci_getreg(port, SCFCR);
1201 if (reg->size)
1202 serial_port_out(port, SCFCR,
1203 serial_port_in(port, SCFCR) |
1204 SCFCR_LOOP);
1205 }
1206}
1207
1208static unsigned int sci_get_mctrl(struct uart_port *port)
1209{
1210 /*
1211 * CTS/RTS is handled in hardware when supported, while nothing
1212 * else is wired up. Keep it simple and simply assert DSR/CAR.
1213 */
1214 return TIOCM_DSR | TIOCM_CAR;
1215}
1216
1217#ifdef CONFIG_SERIAL_SH_SCI_DMA
1218static void sci_dma_tx_complete(void *arg)
1219{
1220 struct sci_port *s = arg;
1221 struct uart_port *port = &s->port;
1222 struct circ_buf *xmit = &port->state->xmit;
1223 unsigned long flags;
1224
1225 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1226
1227 spin_lock_irqsave(&port->lock, flags);
1228
1229 xmit->tail += sg_dma_len(&s->sg_tx);
1230 xmit->tail &= UART_XMIT_SIZE - 1;
1231
1232 port->icount.tx += sg_dma_len(&s->sg_tx);
1233
1234 async_tx_ack(s->desc_tx);
1235 s->desc_tx = NULL;
1236
1237 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1238 uart_write_wakeup(port);
1239
1240 if (!uart_circ_empty(xmit)) {
1241 s->cookie_tx = 0;
1242 schedule_work(&s->work_tx);
1243 } else {
1244 s->cookie_tx = -EINVAL;
1245 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1246 u16 ctrl = serial_port_in(port, SCSCR);
1247 serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE);
1248 }
1249 }
1250
1251 spin_unlock_irqrestore(&port->lock, flags);
1252}
1253
1254/* Locking: called with port lock held */
1255static int sci_dma_rx_push(struct sci_port *s, size_t count)
1256{
1257 struct uart_port *port = &s->port;
1258 struct tty_port *tport = &port->state->port;
1259 int i, active, room;
1260
1261 room = tty_buffer_request_room(tport, count);
1262
1263 if (s->active_rx == s->cookie_rx[0]) {
1264 active = 0;
1265 } else if (s->active_rx == s->cookie_rx[1]) {
1266 active = 1;
1267 } else {
1268 dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
1269 return 0;
1270 }
1271
1272 if (room < count)
1273 dev_warn(port->dev, "Rx overrun: dropping %zu bytes\n",
1274 count - room);
1275 if (!room)
1276 return room;
1277
1278 for (i = 0; i < room; i++)
1279 tty_insert_flip_char(tport, ((u8 *)sg_virt(&s->sg_rx[active]))[i],
1280 TTY_NORMAL);
1281
1282 port->icount.rx += room;
1283
1284 return room;
1285}
1286
1287static void sci_dma_rx_complete(void *arg)
1288{
1289 struct sci_port *s = arg;
1290 struct uart_port *port = &s->port;
1291 unsigned long flags;
1292 int count;
1293
1294 dev_dbg(port->dev, "%s(%d) active #%d\n",
1295 __func__, port->line, s->active_rx);
1296
1297 spin_lock_irqsave(&port->lock, flags);
1298
1299 count = sci_dma_rx_push(s, s->buf_len_rx);
1300
1301 mod_timer(&s->rx_timer, jiffies + s->rx_timeout);
1302
1303 spin_unlock_irqrestore(&port->lock, flags);
1304
1305 if (count)
1306 tty_flip_buffer_push(&port->state->port);
1307
1308 schedule_work(&s->work_rx);
1309}
1310
1311static void sci_rx_dma_release(struct sci_port *s, bool enable_pio)
1312{
1313 struct dma_chan *chan = s->chan_rx;
1314 struct uart_port *port = &s->port;
1315
1316 s->chan_rx = NULL;
1317 s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL;
1318 dma_release_channel(chan);
1319 if (sg_dma_address(&s->sg_rx[0]))
1320 dma_free_coherent(port->dev, s->buf_len_rx * 2,
1321 sg_virt(&s->sg_rx[0]), sg_dma_address(&s->sg_rx[0]));
1322 if (enable_pio)
1323 sci_start_rx(port);
1324}
1325
1326static void sci_tx_dma_release(struct sci_port *s, bool enable_pio)
1327{
1328 struct dma_chan *chan = s->chan_tx;
1329 struct uart_port *port = &s->port;
1330
1331 s->chan_tx = NULL;
1332 s->cookie_tx = -EINVAL;
1333 dma_release_channel(chan);
1334 if (enable_pio)
1335 sci_start_tx(port);
1336}
1337
1338static void sci_submit_rx(struct sci_port *s)
1339{
1340 struct dma_chan *chan = s->chan_rx;
1341 int i;
1342
1343 for (i = 0; i < 2; i++) {
1344 struct scatterlist *sg = &s->sg_rx[i];
1345 struct dma_async_tx_descriptor *desc;
1346
1347 desc = dmaengine_prep_slave_sg(chan,
1348 sg, 1, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
1349
1350 if (desc) {
1351 s->desc_rx[i] = desc;
1352 desc->callback = sci_dma_rx_complete;
1353 desc->callback_param = s;
1354 s->cookie_rx[i] = desc->tx_submit(desc);
1355 }
1356
1357 if (!desc || s->cookie_rx[i] < 0) {
1358 if (i) {
1359 async_tx_ack(s->desc_rx[0]);
1360 s->cookie_rx[0] = -EINVAL;
1361 }
1362 if (desc) {
1363 async_tx_ack(desc);
1364 s->cookie_rx[i] = -EINVAL;
1365 }
1366 dev_warn(s->port.dev,
1367 "failed to re-start DMA, using PIO\n");
1368 sci_rx_dma_release(s, true);
1369 return;
1370 }
1371 dev_dbg(s->port.dev, "%s(): cookie %d to #%d\n",
1372 __func__, s->cookie_rx[i], i);
1373 }
1374
1375 s->active_rx = s->cookie_rx[0];
1376
1377 dma_async_issue_pending(chan);
1378}
1379
1380static void work_fn_rx(struct work_struct *work)
1381{
1382 struct sci_port *s = container_of(work, struct sci_port, work_rx);
1383 struct uart_port *port = &s->port;
1384 struct dma_async_tx_descriptor *desc;
1385 int new;
1386
1387 if (s->active_rx == s->cookie_rx[0]) {
1388 new = 0;
1389 } else if (s->active_rx == s->cookie_rx[1]) {
1390 new = 1;
1391 } else {
1392 dev_err(port->dev, "cookie %d not found!\n", s->active_rx);
1393 return;
1394 }
1395 desc = s->desc_rx[new];
1396
1397 if (dma_async_is_tx_complete(s->chan_rx, s->active_rx, NULL, NULL) !=
1398 DMA_COMPLETE) {
1399 /* Handle incomplete DMA receive */
1400 struct dma_chan *chan = s->chan_rx;
1401 struct shdma_desc *sh_desc = container_of(desc,
1402 struct shdma_desc, async_tx);
1403 unsigned long flags;
1404 int count;
1405
1406 chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
1407 dev_dbg(port->dev, "Read %zu bytes with cookie %d\n",
1408 sh_desc->partial, sh_desc->cookie);
1409
1410 spin_lock_irqsave(&port->lock, flags);
1411 count = sci_dma_rx_push(s, sh_desc->partial);
1412 spin_unlock_irqrestore(&port->lock, flags);
1413
1414 if (count)
1415 tty_flip_buffer_push(&port->state->port);
1416
1417 sci_submit_rx(s);
1418
1419 return;
1420 }
1421
1422 s->cookie_rx[new] = desc->tx_submit(desc);
1423 if (s->cookie_rx[new] < 0) {
1424 dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n");
1425 sci_rx_dma_release(s, true);
1426 return;
1427 }
1428
1429 s->active_rx = s->cookie_rx[!new];
1430
1431 dev_dbg(port->dev, "%s: cookie %d #%d, new active #%d\n",
1432 __func__, s->cookie_rx[new], new, s->active_rx);
1433}
1434
1435static void work_fn_tx(struct work_struct *work)
1436{
1437 struct sci_port *s = container_of(work, struct sci_port, work_tx);
1438 struct dma_async_tx_descriptor *desc;
1439 struct dma_chan *chan = s->chan_tx;
1440 struct uart_port *port = &s->port;
1441 struct circ_buf *xmit = &port->state->xmit;
1442 struct scatterlist *sg = &s->sg_tx;
1443
1444 /*
1445 * DMA is idle now.
1446 * Port xmit buffer is already mapped, and it is one page... Just adjust
1447 * offsets and lengths. Since it is a circular buffer, we have to
1448 * transmit till the end, and then the rest. Take the port lock to get a
1449 * consistent xmit buffer state.
1450 */
1451 spin_lock_irq(&port->lock);
1452 sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
1453 sg_dma_address(sg) = (sg_dma_address(sg) & ~(UART_XMIT_SIZE - 1)) +
1454 sg->offset;
1455 sg_dma_len(sg) = min((int)CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE),
1456 CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE));
1457 spin_unlock_irq(&port->lock);
1458
1459 BUG_ON(!sg_dma_len(sg));
1460
1461 desc = dmaengine_prep_slave_sg(chan,
1462 sg, s->sg_len_tx, DMA_MEM_TO_DEV,
1463 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
1464 if (!desc) {
1465 /* switch to PIO */
1466 sci_tx_dma_release(s, true);
1467 return;
1468 }
1469
1470 dma_sync_sg_for_device(port->dev, sg, 1, DMA_TO_DEVICE);
1471
1472 spin_lock_irq(&port->lock);
1473 s->desc_tx = desc;
1474 desc->callback = sci_dma_tx_complete;
1475 desc->callback_param = s;
1476 spin_unlock_irq(&port->lock);
1477 s->cookie_tx = desc->tx_submit(desc);
1478 if (s->cookie_tx < 0) {
1479 dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n");
1480 /* switch to PIO */
1481 sci_tx_dma_release(s, true);
1482 return;
1483 }
1484
1485 dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n",
1486 __func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx);
1487
1488 dma_async_issue_pending(chan);
1489}
1490#endif
1491
1492static void sci_start_tx(struct uart_port *port)
1493{
1494 struct sci_port *s = to_sci_port(port);
1495 unsigned short ctrl;
1496
1497#ifdef CONFIG_SERIAL_SH_SCI_DMA
1498 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1499 u16 new, scr = serial_port_in(port, SCSCR);
1500 if (s->chan_tx)
1501 new = scr | SCSCR_TDRQE;
1502 else
1503 new = scr & ~SCSCR_TDRQE;
1504 if (new != scr)
1505 serial_port_out(port, SCSCR, new);
1506 }
1507
1508 if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) &&
1509 s->cookie_tx < 0) {
1510 s->cookie_tx = 0;
1511 schedule_work(&s->work_tx);
1512 }
1513#endif
1514
1515 if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1516 /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */
1517 ctrl = serial_port_in(port, SCSCR);
1518 serial_port_out(port, SCSCR, ctrl | SCSCR_TIE);
1519 }
1520}
1521
1522static void sci_stop_tx(struct uart_port *port)
1523{
1524 unsigned short ctrl;
1525
1526 /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */
1527 ctrl = serial_port_in(port, SCSCR);
1528
1529 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1530 ctrl &= ~SCSCR_TDRQE;
1531
1532 ctrl &= ~SCSCR_TIE;
1533
1534 serial_port_out(port, SCSCR, ctrl);
1535}
1536
1537static void sci_start_rx(struct uart_port *port)
1538{
1539 unsigned short ctrl;
1540
1541 ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port);
1542
1543 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1544 ctrl &= ~SCSCR_RDRQE;
1545
1546 serial_port_out(port, SCSCR, ctrl);
1547}
1548
1549static void sci_stop_rx(struct uart_port *port)
1550{
1551 unsigned short ctrl;
1552
1553 ctrl = serial_port_in(port, SCSCR);
1554
1555 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
1556 ctrl &= ~SCSCR_RDRQE;
1557
1558 ctrl &= ~port_rx_irq_mask(port);
1559
1560 serial_port_out(port, SCSCR, ctrl);
1561}
1562
1563static void sci_enable_ms(struct uart_port *port)
1564{
1565 /*
1566 * Not supported by hardware, always a nop.
1567 */
1568}
1569
1570static void sci_break_ctl(struct uart_port *port, int break_state)
1571{
1572 struct sci_port *s = to_sci_port(port);
1573 struct plat_sci_reg *reg = sci_regmap[s->cfg->regtype] + SCSPTR;
1574 unsigned short scscr, scsptr;
1575
1576 /* check wheter the port has SCSPTR */
1577 if (!reg->size) {
1578 /*
1579 * Not supported by hardware. Most parts couple break and rx
1580 * interrupts together, with break detection always enabled.
1581 */
1582 return;
1583 }
1584
1585 scsptr = serial_port_in(port, SCSPTR);
1586 scscr = serial_port_in(port, SCSCR);
1587
1588 if (break_state == -1) {
1589 scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT;
1590 scscr &= ~SCSCR_TE;
1591 } else {
1592 scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO;
1593 scscr |= SCSCR_TE;
1594 }
1595
1596 serial_port_out(port, SCSPTR, scsptr);
1597 serial_port_out(port, SCSCR, scscr);
1598}
1599
1600#ifdef CONFIG_SERIAL_SH_SCI_DMA
1601static bool filter(struct dma_chan *chan, void *slave)
1602{
1603 struct sh_dmae_slave *param = slave;
1604
1605 dev_dbg(chan->device->dev, "%s: slave ID %d\n",
1606 __func__, param->shdma_slave.slave_id);
1607
1608 chan->private = ¶m->shdma_slave;
1609 return true;
1610}
1611
1612static void rx_timer_fn(unsigned long arg)
1613{
1614 struct sci_port *s = (struct sci_port *)arg;
1615 struct uart_port *port = &s->port;
1616 u16 scr = serial_port_in(port, SCSCR);
1617
1618 if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) {
1619 scr &= ~SCSCR_RDRQE;
1620 enable_irq(s->irqs[SCIx_RXI_IRQ]);
1621 }
1622 serial_port_out(port, SCSCR, scr | SCSCR_RIE);
1623 dev_dbg(port->dev, "DMA Rx timed out\n");
1624 schedule_work(&s->work_rx);
1625}
1626
1627static void sci_request_dma(struct uart_port *port)
1628{
1629 struct sci_port *s = to_sci_port(port);
1630 struct sh_dmae_slave *param;
1631 struct dma_chan *chan;
1632 dma_cap_mask_t mask;
1633 int nent;
1634
1635 dev_dbg(port->dev, "%s: port %d\n", __func__, port->line);
1636
1637 if (s->cfg->dma_slave_tx <= 0 || s->cfg->dma_slave_rx <= 0)
1638 return;
1639
1640 dma_cap_zero(mask);
1641 dma_cap_set(DMA_SLAVE, mask);
1642
1643 param = &s->param_tx;
1644
1645 /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_TX */
1646 param->shdma_slave.slave_id = s->cfg->dma_slave_tx;
1647
1648 s->cookie_tx = -EINVAL;
1649 chan = dma_request_channel(mask, filter, param);
1650 dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan);
1651 if (chan) {
1652 s->chan_tx = chan;
1653 sg_init_table(&s->sg_tx, 1);
1654 /* UART circular tx buffer is an aligned page. */
1655 BUG_ON((uintptr_t)port->state->xmit.buf & ~PAGE_MASK);
1656 sg_set_page(&s->sg_tx, virt_to_page(port->state->xmit.buf),
1657 UART_XMIT_SIZE,
1658 (uintptr_t)port->state->xmit.buf & ~PAGE_MASK);
1659 nent = dma_map_sg(port->dev, &s->sg_tx, 1, DMA_TO_DEVICE);
1660 if (!nent)
1661 sci_tx_dma_release(s, false);
1662 else
1663 dev_dbg(port->dev, "%s: mapped %d@%p to %pad\n",
1664 __func__,
1665 sg_dma_len(&s->sg_tx), port->state->xmit.buf,
1666 &sg_dma_address(&s->sg_tx));
1667
1668 s->sg_len_tx = nent;
1669
1670 INIT_WORK(&s->work_tx, work_fn_tx);
1671 }
1672
1673 param = &s->param_rx;
1674
1675 /* Slave ID, e.g., SHDMA_SLAVE_SCIF0_RX */
1676 param->shdma_slave.slave_id = s->cfg->dma_slave_rx;
1677
1678 chan = dma_request_channel(mask, filter, param);
1679 dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan);
1680 if (chan) {
1681 dma_addr_t dma[2];
1682 void *buf[2];
1683 int i;
1684
1685 s->chan_rx = chan;
1686
1687 s->buf_len_rx = 2 * max(16, (int)port->fifosize);
1688 buf[0] = dma_alloc_coherent(port->dev, s->buf_len_rx * 2,
1689 &dma[0], GFP_KERNEL);
1690
1691 if (!buf[0]) {
1692 dev_warn(port->dev,
1693 "failed to allocate dma buffer, using PIO\n");
1694 sci_rx_dma_release(s, true);
1695 return;
1696 }
1697
1698 buf[1] = buf[0] + s->buf_len_rx;
1699 dma[1] = dma[0] + s->buf_len_rx;
1700
1701 for (i = 0; i < 2; i++) {
1702 struct scatterlist *sg = &s->sg_rx[i];
1703
1704 sg_init_table(sg, 1);
1705 sg_set_page(sg, virt_to_page(buf[i]), s->buf_len_rx,
1706 (uintptr_t)buf[i] & ~PAGE_MASK);
1707 sg_dma_address(sg) = dma[i];
1708 }
1709
1710 INIT_WORK(&s->work_rx, work_fn_rx);
1711 setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s);
1712
1713 sci_submit_rx(s);
1714 }
1715}
1716
1717static void sci_free_dma(struct uart_port *port)
1718{
1719 struct sci_port *s = to_sci_port(port);
1720
1721 if (s->chan_tx)
1722 sci_tx_dma_release(s, false);
1723 if (s->chan_rx)
1724 sci_rx_dma_release(s, false);
1725}
1726#else
1727static inline void sci_request_dma(struct uart_port *port)
1728{
1729}
1730
1731static inline void sci_free_dma(struct uart_port *port)
1732{
1733}
1734#endif
1735
1736static int sci_startup(struct uart_port *port)
1737{
1738 struct sci_port *s = to_sci_port(port);
1739 unsigned long flags;
1740 int ret;
1741
1742 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1743
1744 ret = sci_request_irq(s);
1745 if (unlikely(ret < 0))
1746 return ret;
1747
1748 sci_request_dma(port);
1749
1750 spin_lock_irqsave(&port->lock, flags);
1751 sci_start_tx(port);
1752 sci_start_rx(port);
1753 spin_unlock_irqrestore(&port->lock, flags);
1754
1755 return 0;
1756}
1757
1758static void sci_shutdown(struct uart_port *port)
1759{
1760 struct sci_port *s = to_sci_port(port);
1761 unsigned long flags;
1762
1763 dev_dbg(port->dev, "%s(%d)\n", __func__, port->line);
1764
1765 spin_lock_irqsave(&port->lock, flags);
1766 sci_stop_rx(port);
1767 sci_stop_tx(port);
1768 spin_unlock_irqrestore(&port->lock, flags);
1769
1770 sci_free_dma(port);
1771 sci_free_irq(s);
1772}
1773
1774static unsigned int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
1775 unsigned long freq)
1776{
1777 if (s->sampling_rate)
1778 return DIV_ROUND_CLOSEST(freq, s->sampling_rate * bps) - 1;
1779
1780 /* Warn, but use a safe default */
1781 WARN_ON(1);
1782
1783 return ((freq + 16 * bps) / (32 * bps) - 1);
1784}
1785
1786/* calculate sample rate, BRR, and clock select for HSCIF */
1787static void sci_baud_calc_hscif(unsigned int bps, unsigned long freq,
1788 int *brr, unsigned int *srr,
1789 unsigned int *cks)
1790{
1791 int sr, c, br, err;
1792 int min_err = 1000; /* 100% */
1793
1794 /* Find the combination of sample rate and clock select with the
1795 smallest deviation from the desired baud rate. */
1796 for (sr = 8; sr <= 32; sr++) {
1797 for (c = 0; c <= 3; c++) {
1798 /* integerized formulas from HSCIF documentation */
1799 br = freq / (sr * (1 << (2 * c + 1)) * bps) - 1;
1800 if (br < 0 || br > 255)
1801 continue;
1802 err = freq / ((br + 1) * bps * sr *
1803 (1 << (2 * c + 1)) / 1000) - 1000;
1804 if (min_err > err) {
1805 min_err = err;
1806 *brr = br;
1807 *srr = sr - 1;
1808 *cks = c;
1809 }
1810 }
1811 }
1812
1813 if (min_err == 1000) {
1814 WARN_ON(1);
1815 /* use defaults */
1816 *brr = 255;
1817 *srr = 15;
1818 *cks = 0;
1819 }
1820}
1821
1822static void sci_reset(struct uart_port *port)
1823{
1824 struct plat_sci_reg *reg;
1825 unsigned int status;
1826
1827 do {
1828 status = serial_port_in(port, SCxSR);
1829 } while (!(status & SCxSR_TEND(port)));
1830
1831 serial_port_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */
1832
1833 reg = sci_getreg(port, SCFCR);
1834 if (reg->size)
1835 serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST);
1836}
1837
1838static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
1839 struct ktermios *old)
1840{
1841 struct sci_port *s = to_sci_port(port);
1842 struct plat_sci_reg *reg;
1843 unsigned int baud, smr_val, max_baud, cks = 0;
1844 int t = -1;
1845 unsigned int srr = 15;
1846
1847 /*
1848 * earlyprintk comes here early on with port->uartclk set to zero.
1849 * the clock framework is not up and running at this point so here
1850 * we assume that 115200 is the maximum baud rate. please note that
1851 * the baud rate is not programmed during earlyprintk - it is assumed
1852 * that the previous boot loader has enabled required clocks and
1853 * setup the baud rate generator hardware for us already.
1854 */
1855 max_baud = port->uartclk ? port->uartclk / 16 : 115200;
1856
1857 baud = uart_get_baud_rate(port, termios, old, 0, max_baud);
1858 if (likely(baud && port->uartclk)) {
1859 if (s->cfg->type == PORT_HSCIF) {
1860 sci_baud_calc_hscif(baud, port->uartclk, &t, &srr,
1861 &cks);
1862 } else {
1863 t = sci_scbrr_calc(s, baud, port->uartclk);
1864 for (cks = 0; t >= 256 && cks <= 3; cks++)
1865 t >>= 2;
1866 }
1867 }
1868
1869 sci_port_enable(s);
1870
1871 sci_reset(port);
1872
1873 smr_val = serial_port_in(port, SCSMR) & 3;
1874
1875 if ((termios->c_cflag & CSIZE) == CS7)
1876 smr_val |= SCSMR_CHR;
1877 if (termios->c_cflag & PARENB)
1878 smr_val |= SCSMR_PE;
1879 if (termios->c_cflag & PARODD)
1880 smr_val |= SCSMR_PE | SCSMR_ODD;
1881 if (termios->c_cflag & CSTOPB)
1882 smr_val |= SCSMR_STOP;
1883
1884 uart_update_timeout(port, termios->c_cflag, baud);
1885
1886 dev_dbg(port->dev, "%s: SMR %x, cks %x, t %x, SCSCR %x\n",
1887 __func__, smr_val, cks, t, s->cfg->scscr);
1888
1889 if (t >= 0) {
1890 serial_port_out(port, SCSMR, (smr_val & ~SCSMR_CKS) | cks);
1891 serial_port_out(port, SCBRR, t);
1892 reg = sci_getreg(port, HSSRR);
1893 if (reg->size)
1894 serial_port_out(port, HSSRR, srr | HSCIF_SRE);
1895 udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
1896 } else
1897 serial_port_out(port, SCSMR, smr_val);
1898
1899 sci_init_pins(port, termios->c_cflag);
1900
1901 reg = sci_getreg(port, SCFCR);
1902 if (reg->size) {
1903 unsigned short ctrl = serial_port_in(port, SCFCR);
1904
1905 if (s->cfg->capabilities & SCIx_HAVE_RTSCTS) {
1906 if (termios->c_cflag & CRTSCTS)
1907 ctrl |= SCFCR_MCE;
1908 else
1909 ctrl &= ~SCFCR_MCE;
1910 }
1911
1912 /*
1913 * As we've done a sci_reset() above, ensure we don't
1914 * interfere with the FIFOs while toggling MCE. As the
1915 * reset values could still be set, simply mask them out.
1916 */
1917 ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST);
1918
1919 serial_port_out(port, SCFCR, ctrl);
1920 }
1921
1922 serial_port_out(port, SCSCR, s->cfg->scscr);
1923
1924#ifdef CONFIG_SERIAL_SH_SCI_DMA
1925 /*
1926 * Calculate delay for 1.5 DMA buffers: see
1927 * drivers/serial/serial_core.c::uart_update_timeout(). With 10 bits
1928 * (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above function
1929 * calculates 1 jiffie for the data plus 5 jiffies for the "slop(e)."
1930 * Then below we calculate 3 jiffies (12ms) for 1.5 DMA buffers (3 FIFO
1931 * sizes), but it has been found out experimentally, that this is not
1932 * enough: the driver too often needlessly runs on a DMA timeout. 20ms
1933 * as a minimum seem to work perfectly.
1934 */
1935 if (s->chan_rx) {
1936 s->rx_timeout = (port->timeout - HZ / 50) * s->buf_len_rx * 3 /
1937 port->fifosize / 2;
1938 dev_dbg(port->dev, "DMA Rx t-out %ums, tty t-out %u jiffies\n",
1939 s->rx_timeout * 1000 / HZ, port->timeout);
1940 if (s->rx_timeout < msecs_to_jiffies(20))
1941 s->rx_timeout = msecs_to_jiffies(20);
1942 }
1943#endif
1944
1945 if ((termios->c_cflag & CREAD) != 0)
1946 sci_start_rx(port);
1947
1948 sci_port_disable(s);
1949}
1950
1951static void sci_pm(struct uart_port *port, unsigned int state,
1952 unsigned int oldstate)
1953{
1954 struct sci_port *sci_port = to_sci_port(port);
1955
1956 switch (state) {
1957 case UART_PM_STATE_OFF:
1958 sci_port_disable(sci_port);
1959 break;
1960 default:
1961 sci_port_enable(sci_port);
1962 break;
1963 }
1964}
1965
1966static const char *sci_type(struct uart_port *port)
1967{
1968 switch (port->type) {
1969 case PORT_IRDA:
1970 return "irda";
1971 case PORT_SCI:
1972 return "sci";
1973 case PORT_SCIF:
1974 return "scif";
1975 case PORT_SCIFA:
1976 return "scifa";
1977 case PORT_SCIFB:
1978 return "scifb";
1979 case PORT_HSCIF:
1980 return "hscif";
1981 }
1982
1983 return NULL;
1984}
1985
1986static inline unsigned long sci_port_size(struct uart_port *port)
1987{
1988 /*
1989 * Pick an arbitrary size that encapsulates all of the base
1990 * registers by default. This can be optimized later, or derived
1991 * from platform resource data at such a time that ports begin to
1992 * behave more erratically.
1993 */
1994 if (port->type == PORT_HSCIF)
1995 return 96;
1996 else
1997 return 64;
1998}
1999
2000static int sci_remap_port(struct uart_port *port)
2001{
2002 unsigned long size = sci_port_size(port);
2003
2004 /*
2005 * Nothing to do if there's already an established membase.
2006 */
2007 if (port->membase)
2008 return 0;
2009
2010 if (port->flags & UPF_IOREMAP) {
2011 port->membase = ioremap_nocache(port->mapbase, size);
2012 if (unlikely(!port->membase)) {
2013 dev_err(port->dev, "can't remap port#%d\n", port->line);
2014 return -ENXIO;
2015 }
2016 } else {
2017 /*
2018 * For the simple (and majority of) cases where we don't
2019 * need to do any remapping, just cast the cookie
2020 * directly.
2021 */
2022 port->membase = (void __iomem *)(uintptr_t)port->mapbase;
2023 }
2024
2025 return 0;
2026}
2027
2028static void sci_release_port(struct uart_port *port)
2029{
2030 if (port->flags & UPF_IOREMAP) {
2031 iounmap(port->membase);
2032 port->membase = NULL;
2033 }
2034
2035 release_mem_region(port->mapbase, sci_port_size(port));
2036}
2037
2038static int sci_request_port(struct uart_port *port)
2039{
2040 unsigned long size = sci_port_size(port);
2041 struct resource *res;
2042 int ret;
2043
2044 res = request_mem_region(port->mapbase, size, dev_name(port->dev));
2045 if (unlikely(res == NULL))
2046 return -EBUSY;
2047
2048 ret = sci_remap_port(port);
2049 if (unlikely(ret != 0)) {
2050 release_resource(res);
2051 return ret;
2052 }
2053
2054 return 0;
2055}
2056
2057static void sci_config_port(struct uart_port *port, int flags)
2058{
2059 if (flags & UART_CONFIG_TYPE) {
2060 struct sci_port *sport = to_sci_port(port);
2061
2062 port->type = sport->cfg->type;
2063 sci_request_port(port);
2064 }
2065}
2066
2067static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
2068{
2069 if (ser->baud_base < 2400)
2070 /* No paper tape reader for Mitch.. */
2071 return -EINVAL;
2072
2073 return 0;
2074}
2075
2076static struct uart_ops sci_uart_ops = {
2077 .tx_empty = sci_tx_empty,
2078 .set_mctrl = sci_set_mctrl,
2079 .get_mctrl = sci_get_mctrl,
2080 .start_tx = sci_start_tx,
2081 .stop_tx = sci_stop_tx,
2082 .stop_rx = sci_stop_rx,
2083 .enable_ms = sci_enable_ms,
2084 .break_ctl = sci_break_ctl,
2085 .startup = sci_startup,
2086 .shutdown = sci_shutdown,
2087 .set_termios = sci_set_termios,
2088 .pm = sci_pm,
2089 .type = sci_type,
2090 .release_port = sci_release_port,
2091 .request_port = sci_request_port,
2092 .config_port = sci_config_port,
2093 .verify_port = sci_verify_port,
2094#ifdef CONFIG_CONSOLE_POLL
2095 .poll_get_char = sci_poll_get_char,
2096 .poll_put_char = sci_poll_put_char,
2097#endif
2098};
2099
2100static int sci_init_single(struct platform_device *dev,
2101 struct sci_port *sci_port, unsigned int index,
2102 struct plat_sci_port *p, bool early)
2103{
2104 struct uart_port *port = &sci_port->port;
2105 const struct resource *res;
2106 unsigned int sampling_rate;
2107 unsigned int i;
2108 int ret;
2109
2110 sci_port->cfg = p;
2111
2112 port->ops = &sci_uart_ops;
2113 port->iotype = UPIO_MEM;
2114 port->line = index;
2115
2116 res = platform_get_resource(dev, IORESOURCE_MEM, 0);
2117 if (res == NULL)
2118 return -ENOMEM;
2119
2120 port->mapbase = res->start;
2121
2122 for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i)
2123 sci_port->irqs[i] = platform_get_irq(dev, i);
2124
2125 /* The SCI generates several interrupts. They can be muxed together or
2126 * connected to different interrupt lines. In the muxed case only one
2127 * interrupt resource is specified. In the non-muxed case three or four
2128 * interrupt resources are specified, as the BRI interrupt is optional.
2129 */
2130 if (sci_port->irqs[0] < 0)
2131 return -ENXIO;
2132
2133 if (sci_port->irqs[1] < 0) {
2134 sci_port->irqs[1] = sci_port->irqs[0];
2135 sci_port->irqs[2] = sci_port->irqs[0];
2136 sci_port->irqs[3] = sci_port->irqs[0];
2137 }
2138
2139 if (p->regtype == SCIx_PROBE_REGTYPE) {
2140 ret = sci_probe_regmap(p);
2141 if (unlikely(ret))
2142 return ret;
2143 }
2144
2145 switch (p->type) {
2146 case PORT_SCIFB:
2147 port->fifosize = 256;
2148 sci_port->overrun_bit = 9;
2149 sampling_rate = 16;
2150 break;
2151 case PORT_HSCIF:
2152 port->fifosize = 128;
2153 sampling_rate = 0;
2154 sci_port->overrun_bit = 0;
2155 break;
2156 case PORT_SCIFA:
2157 port->fifosize = 64;
2158 sci_port->overrun_bit = 9;
2159 sampling_rate = 16;
2160 break;
2161 case PORT_SCIF:
2162 port->fifosize = 16;
2163 if (p->regtype == SCIx_SH7705_SCIF_REGTYPE) {
2164 sci_port->overrun_bit = 9;
2165 sampling_rate = 16;
2166 } else {
2167 sci_port->overrun_bit = 0;
2168 sampling_rate = 32;
2169 }
2170 break;
2171 default:
2172 port->fifosize = 1;
2173 sci_port->overrun_bit = 5;
2174 sampling_rate = 32;
2175 break;
2176 }
2177
2178 /* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't
2179 * match the SoC datasheet, this should be investigated. Let platform
2180 * data override the sampling rate for now.
2181 */
2182 sci_port->sampling_rate = p->sampling_rate ? p->sampling_rate
2183 : sampling_rate;
2184
2185 if (!early) {
2186 sci_port->iclk = clk_get(&dev->dev, "sci_ick");
2187 if (IS_ERR(sci_port->iclk)) {
2188 sci_port->iclk = clk_get(&dev->dev, "peripheral_clk");
2189 if (IS_ERR(sci_port->iclk)) {
2190 dev_err(&dev->dev, "can't get iclk\n");
2191 return PTR_ERR(sci_port->iclk);
2192 }
2193 }
2194
2195 /*
2196 * The function clock is optional, ignore it if we can't
2197 * find it.
2198 */
2199 sci_port->fclk = clk_get(&dev->dev, "sci_fck");
2200 if (IS_ERR(sci_port->fclk))
2201 sci_port->fclk = NULL;
2202
2203 port->dev = &dev->dev;
2204
2205 pm_runtime_enable(&dev->dev);
2206 }
2207
2208 sci_port->break_timer.data = (unsigned long)sci_port;
2209 sci_port->break_timer.function = sci_break_timer;
2210 init_timer(&sci_port->break_timer);
2211
2212 /*
2213 * Establish some sensible defaults for the error detection.
2214 */
2215 sci_port->error_mask = (p->type == PORT_SCI) ?
2216 SCI_DEFAULT_ERROR_MASK : SCIF_DEFAULT_ERROR_MASK;
2217
2218 /*
2219 * Establish sensible defaults for the overrun detection, unless
2220 * the part has explicitly disabled support for it.
2221 */
2222
2223 /*
2224 * Make the error mask inclusive of overrun detection, if
2225 * supported.
2226 */
2227 sci_port->error_mask |= 1 << sci_port->overrun_bit;
2228
2229 port->type = p->type;
2230 port->flags = UPF_FIXED_PORT | p->flags;
2231 port->regshift = p->regshift;
2232
2233 /*
2234 * The UART port needs an IRQ value, so we peg this to the RX IRQ
2235 * for the multi-IRQ ports, which is where we are primarily
2236 * concerned with the shutdown path synchronization.
2237 *
2238 * For the muxed case there's nothing more to do.
2239 */
2240 port->irq = sci_port->irqs[SCIx_RXI_IRQ];
2241 port->irqflags = 0;
2242
2243 port->serial_in = sci_serial_in;
2244 port->serial_out = sci_serial_out;
2245
2246 if (p->dma_slave_tx > 0 && p->dma_slave_rx > 0)
2247 dev_dbg(port->dev, "DMA tx %d, rx %d\n",
2248 p->dma_slave_tx, p->dma_slave_rx);
2249
2250 return 0;
2251}
2252
2253static void sci_cleanup_single(struct sci_port *port)
2254{
2255 clk_put(port->iclk);
2256 clk_put(port->fclk);
2257
2258 pm_runtime_disable(port->port.dev);
2259}
2260
2261#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
2262static void serial_console_putchar(struct uart_port *port, int ch)
2263{
2264 sci_poll_put_char(port, ch);
2265}
2266
2267/*
2268 * Print a string to the serial port trying not to disturb
2269 * any possible real use of the port...
2270 */
2271static void serial_console_write(struct console *co, const char *s,
2272 unsigned count)
2273{
2274 struct sci_port *sci_port = &sci_ports[co->index];
2275 struct uart_port *port = &sci_port->port;
2276 unsigned short bits, ctrl;
2277 unsigned long flags;
2278 int locked = 1;
2279
2280 local_irq_save(flags);
2281 if (port->sysrq)
2282 locked = 0;
2283 else if (oops_in_progress)
2284 locked = spin_trylock(&port->lock);
2285 else
2286 spin_lock(&port->lock);
2287
2288 /* first save the SCSCR then disable the interrupts */
2289 ctrl = serial_port_in(port, SCSCR);
2290 serial_port_out(port, SCSCR, sci_port->cfg->scscr);
2291
2292 uart_console_write(port, s, count, serial_console_putchar);
2293
2294 /* wait until fifo is empty and last bit has been transmitted */
2295 bits = SCxSR_TDxE(port) | SCxSR_TEND(port);
2296 while ((serial_port_in(port, SCxSR) & bits) != bits)
2297 cpu_relax();
2298
2299 /* restore the SCSCR */
2300 serial_port_out(port, SCSCR, ctrl);
2301
2302 if (locked)
2303 spin_unlock(&port->lock);
2304 local_irq_restore(flags);
2305}
2306
2307static int serial_console_setup(struct console *co, char *options)
2308{
2309 struct sci_port *sci_port;
2310 struct uart_port *port;
2311 int baud = 115200;
2312 int bits = 8;
2313 int parity = 'n';
2314 int flow = 'n';
2315 int ret;
2316
2317 /*
2318 * Refuse to handle any bogus ports.
2319 */
2320 if (co->index < 0 || co->index >= SCI_NPORTS)
2321 return -ENODEV;
2322
2323 sci_port = &sci_ports[co->index];
2324 port = &sci_port->port;
2325
2326 /*
2327 * Refuse to handle uninitialized ports.
2328 */
2329 if (!port->ops)
2330 return -ENODEV;
2331
2332 ret = sci_remap_port(port);
2333 if (unlikely(ret != 0))
2334 return ret;
2335
2336 if (options)
2337 uart_parse_options(options, &baud, &parity, &bits, &flow);
2338
2339 return uart_set_options(port, co, baud, parity, bits, flow);
2340}
2341
2342static struct console serial_console = {
2343 .name = "ttySC",
2344 .device = uart_console_device,
2345 .write = serial_console_write,
2346 .setup = serial_console_setup,
2347 .flags = CON_PRINTBUFFER,
2348 .index = -1,
2349 .data = &sci_uart_driver,
2350};
2351
2352static struct console early_serial_console = {
2353 .name = "early_ttySC",
2354 .write = serial_console_write,
2355 .flags = CON_PRINTBUFFER,
2356 .index = -1,
2357};
2358
2359static char early_serial_buf[32];
2360
2361static int sci_probe_earlyprintk(struct platform_device *pdev)
2362{
2363 struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
2364
2365 if (early_serial_console.data)
2366 return -EEXIST;
2367
2368 early_serial_console.index = pdev->id;
2369
2370 sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true);
2371
2372 serial_console_setup(&early_serial_console, early_serial_buf);
2373
2374 if (!strstr(early_serial_buf, "keep"))
2375 early_serial_console.flags |= CON_BOOT;
2376
2377 register_console(&early_serial_console);
2378 return 0;
2379}
2380
2381#define SCI_CONSOLE (&serial_console)
2382
2383#else
2384static inline int sci_probe_earlyprintk(struct platform_device *pdev)
2385{
2386 return -EINVAL;
2387}
2388
2389#define SCI_CONSOLE NULL
2390
2391#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
2392
2393static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
2394
2395static struct uart_driver sci_uart_driver = {
2396 .owner = THIS_MODULE,
2397 .driver_name = "sci",
2398 .dev_name = "ttySC",
2399 .major = SCI_MAJOR,
2400 .minor = SCI_MINOR_START,
2401 .nr = SCI_NPORTS,
2402 .cons = SCI_CONSOLE,
2403};
2404
2405static int sci_remove(struct platform_device *dev)
2406{
2407 struct sci_port *port = platform_get_drvdata(dev);
2408
2409 cpufreq_unregister_notifier(&port->freq_transition,
2410 CPUFREQ_TRANSITION_NOTIFIER);
2411
2412 uart_remove_one_port(&sci_uart_driver, &port->port);
2413
2414 sci_cleanup_single(port);
2415
2416 return 0;
2417}
2418
2419struct sci_port_info {
2420 unsigned int type;
2421 unsigned int regtype;
2422};
2423
2424static const struct of_device_id of_sci_match[] = {
2425 {
2426 .compatible = "renesas,scif",
2427 .data = &(const struct sci_port_info) {
2428 .type = PORT_SCIF,
2429 .regtype = SCIx_SH4_SCIF_REGTYPE,
2430 },
2431 }, {
2432 .compatible = "renesas,scifa",
2433 .data = &(const struct sci_port_info) {
2434 .type = PORT_SCIFA,
2435 .regtype = SCIx_SCIFA_REGTYPE,
2436 },
2437 }, {
2438 .compatible = "renesas,scifb",
2439 .data = &(const struct sci_port_info) {
2440 .type = PORT_SCIFB,
2441 .regtype = SCIx_SCIFB_REGTYPE,
2442 },
2443 }, {
2444 .compatible = "renesas,hscif",
2445 .data = &(const struct sci_port_info) {
2446 .type = PORT_HSCIF,
2447 .regtype = SCIx_HSCIF_REGTYPE,
2448 },
2449 }, {
2450 /* Terminator */
2451 },
2452};
2453MODULE_DEVICE_TABLE(of, of_sci_match);
2454
2455static struct plat_sci_port *
2456sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id)
2457{
2458 struct device_node *np = pdev->dev.of_node;
2459 const struct of_device_id *match;
2460 const struct sci_port_info *info;
2461 struct plat_sci_port *p;
2462 int id;
2463
2464 if (!IS_ENABLED(CONFIG_OF) || !np)
2465 return NULL;
2466
2467 match = of_match_node(of_sci_match, pdev->dev.of_node);
2468 if (!match)
2469 return NULL;
2470
2471 info = match->data;
2472
2473 p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
2474 if (!p) {
2475 dev_err(&pdev->dev, "failed to allocate DT config data\n");
2476 return NULL;
2477 }
2478
2479 /* Get the line number for the aliases node. */
2480 id = of_alias_get_id(np, "serial");
2481 if (id < 0) {
2482 dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
2483 return NULL;
2484 }
2485
2486 *dev_id = id;
2487
2488 p->flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
2489 p->type = info->type;
2490 p->regtype = info->regtype;
2491 p->scscr = SCSCR_RE | SCSCR_TE;
2492
2493 return p;
2494}
2495
2496static int sci_probe_single(struct platform_device *dev,
2497 unsigned int index,
2498 struct plat_sci_port *p,
2499 struct sci_port *sciport)
2500{
2501 int ret;
2502
2503 /* Sanity check */
2504 if (unlikely(index >= SCI_NPORTS)) {
2505 dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n",
2506 index+1, SCI_NPORTS);
2507 dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n");
2508 return -EINVAL;
2509 }
2510
2511 ret = sci_init_single(dev, sciport, index, p, false);
2512 if (ret)
2513 return ret;
2514
2515 ret = uart_add_one_port(&sci_uart_driver, &sciport->port);
2516 if (ret) {
2517 sci_cleanup_single(sciport);
2518 return ret;
2519 }
2520
2521 return 0;
2522}
2523
2524static int sci_probe(struct platform_device *dev)
2525{
2526 struct plat_sci_port *p;
2527 struct sci_port *sp;
2528 unsigned int dev_id;
2529 int ret;
2530
2531 /*
2532 * If we've come here via earlyprintk initialization, head off to
2533 * the special early probe. We don't have sufficient device state
2534 * to make it beyond this yet.
2535 */
2536 if (is_early_platform_device(dev))
2537 return sci_probe_earlyprintk(dev);
2538
2539 if (dev->dev.of_node) {
2540 p = sci_parse_dt(dev, &dev_id);
2541 if (p == NULL)
2542 return -EINVAL;
2543 } else {
2544 p = dev->dev.platform_data;
2545 if (p == NULL) {
2546 dev_err(&dev->dev, "no platform data supplied\n");
2547 return -EINVAL;
2548 }
2549
2550 dev_id = dev->id;
2551 }
2552
2553 sp = &sci_ports[dev_id];
2554 platform_set_drvdata(dev, sp);
2555
2556 ret = sci_probe_single(dev, dev_id, p, sp);
2557 if (ret)
2558 return ret;
2559
2560 sp->freq_transition.notifier_call = sci_notifier;
2561
2562 ret = cpufreq_register_notifier(&sp->freq_transition,
2563 CPUFREQ_TRANSITION_NOTIFIER);
2564 if (unlikely(ret < 0)) {
2565 uart_remove_one_port(&sci_uart_driver, &sp->port);
2566 sci_cleanup_single(sp);
2567 return ret;
2568 }
2569
2570#ifdef CONFIG_SH_STANDARD_BIOS
2571 sh_bios_gdb_detach();
2572#endif
2573
2574 return 0;
2575}
2576
2577static int sci_suspend(struct device *dev)
2578{
2579 struct sci_port *sport = dev_get_drvdata(dev);
2580
2581 if (sport)
2582 uart_suspend_port(&sci_uart_driver, &sport->port);
2583
2584 return 0;
2585}
2586
2587static int sci_resume(struct device *dev)
2588{
2589 struct sci_port *sport = dev_get_drvdata(dev);
2590
2591 if (sport)
2592 uart_resume_port(&sci_uart_driver, &sport->port);
2593
2594 return 0;
2595}
2596
2597static const struct dev_pm_ops sci_dev_pm_ops = {
2598 .suspend = sci_suspend,
2599 .resume = sci_resume,
2600};
2601
2602static struct platform_driver sci_driver = {
2603 .probe = sci_probe,
2604 .remove = sci_remove,
2605 .driver = {
2606 .name = "sh-sci",
2607 .owner = THIS_MODULE,
2608 .pm = &sci_dev_pm_ops,
2609 .of_match_table = of_match_ptr(of_sci_match),
2610 },
2611};
2612
2613static int __init sci_init(void)
2614{
2615 int ret;
2616
2617 pr_info("%s\n", banner);
2618
2619 ret = uart_register_driver(&sci_uart_driver);
2620 if (likely(ret == 0)) {
2621 ret = platform_driver_register(&sci_driver);
2622 if (unlikely(ret))
2623 uart_unregister_driver(&sci_uart_driver);
2624 }
2625
2626 return ret;
2627}
2628
2629static void __exit sci_exit(void)
2630{
2631 platform_driver_unregister(&sci_driver);
2632 uart_unregister_driver(&sci_uart_driver);
2633}
2634
2635#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
2636early_platform_init_buffer("earlyprintk", &sci_driver,
2637 early_serial_buf, ARRAY_SIZE(early_serial_buf));
2638#endif
2639module_init(sci_init);
2640module_exit(sci_exit);
2641
2642MODULE_LICENSE("GPL");
2643MODULE_ALIAS("platform:sh-sci");
2644MODULE_AUTHOR("Paul Mundt");
2645MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver");