1 /*
2 * Driver core for Samsung SoC onboard UARTs.
3 *
4 * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
5 * http://armlinux.simtec.co.uk/
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12 /* Hote on 2410 error handling
13 *
14 * The s3c2410 manual has a love/hate affair with the contents of the
15 * UERSTAT register in the UART blocks, and keeps marking some of the
16 * error bits as reserved. Having checked with the s3c2410x01,
17 * it copes with BREAKs properly, so I am happy to ignore the RESERVED
18 * feature from the latter versions of the manual.
19 *
20 * If it becomes aparrent that latter versions of the 2410 remove these
21 * bits, then action will have to be taken to differentiate the versions
22 * and change the policy on BREAK
23 *
24 * BJD, 04-Nov-2004
25 */
26
27 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
28 #define SUPPORT_SYSRQ
29 #endif
30
31 #include <linux/dmaengine.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/slab.h>
34 #include <linux/module.h>
35 #include <linux/ioport.h>
36 #include <linux/io.h>
37 #include <linux/platform_device.h>
38 #include <linux/init.h>
39 #include <linux/sysrq.h>
40 #include <linux/console.h>
41 #include <linux/tty.h>
42 #include <linux/tty_flip.h>
43 #include <linux/serial_core.h>
44 #include <linux/serial.h>
45 #include <linux/serial_s3c.h>
46 #include <linux/delay.h>
47 #include <linux/clk.h>
48 #include <linux/cpufreq.h>
49 #include <linux/of.h>
50
51 #include <asm/irq.h>
52
53 #include "samsung.h"
54
55 #if defined(CONFIG_SERIAL_SAMSUNG_DEBUG) && \
56 !defined(MODULE)
57
58 extern void printascii(const char *);
59
60 __printf(1, 2)
dbg(const char * fmt,...)61 static void dbg(const char *fmt, ...)
62 {
63 va_list va;
64 char buff[256];
65
66 va_start(va, fmt);
67 vscnprintf(buff, sizeof(buff), fmt, va);
68 va_end(va);
69
70 printascii(buff);
71 }
72
73 #else
74 #define dbg(fmt, ...) do { if (0) no_printk(fmt, ##__VA_ARGS__); } while (0)
75 #endif
76
77 /* UART name and device definitions */
78
79 #define S3C24XX_SERIAL_NAME "ttySAC"
80 #define S3C24XX_SERIAL_MAJOR 204
81 #define S3C24XX_SERIAL_MINOR 64
82
83 #define S3C24XX_TX_PIO 1
84 #define S3C24XX_TX_DMA 2
85 #define S3C24XX_RX_PIO 1
86 #define S3C24XX_RX_DMA 2
87 /* macros to change one thing to another */
88
89 #define tx_enabled(port) ((port)->unused[0])
90 #define rx_enabled(port) ((port)->unused[1])
91
92 /* flag to ignore all characters coming in */
93 #define RXSTAT_DUMMY_READ (0x10000000)
94
to_ourport(struct uart_port * port)95 static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
96 {
97 return container_of(port, struct s3c24xx_uart_port, port);
98 }
99
100 /* translate a port to the device name */
101
s3c24xx_serial_portname(struct uart_port * port)102 static inline const char *s3c24xx_serial_portname(struct uart_port *port)
103 {
104 return to_platform_device(port->dev)->name;
105 }
106
s3c24xx_serial_txempty_nofifo(struct uart_port * port)107 static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
108 {
109 return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;
110 }
111
112 /*
113 * s3c64xx and later SoC's include the interrupt mask and status registers in
114 * the controller itself, unlike the s3c24xx SoC's which have these registers
115 * in the interrupt controller. Check if the port type is s3c64xx or higher.
116 */
s3c24xx_serial_has_interrupt_mask(struct uart_port * port)117 static int s3c24xx_serial_has_interrupt_mask(struct uart_port *port)
118 {
119 return to_ourport(port)->info->type == PORT_S3C6400;
120 }
121
s3c24xx_serial_rx_enable(struct uart_port * port)122 static void s3c24xx_serial_rx_enable(struct uart_port *port)
123 {
124 unsigned long flags;
125 unsigned int ucon, ufcon;
126 int count = 10000;
127
128 spin_lock_irqsave(&port->lock, flags);
129
130 while (--count && !s3c24xx_serial_txempty_nofifo(port))
131 udelay(100);
132
133 ufcon = rd_regl(port, S3C2410_UFCON);
134 ufcon |= S3C2410_UFCON_RESETRX;
135 wr_regl(port, S3C2410_UFCON, ufcon);
136
137 ucon = rd_regl(port, S3C2410_UCON);
138 ucon |= S3C2410_UCON_RXIRQMODE;
139 wr_regl(port, S3C2410_UCON, ucon);
140
141 rx_enabled(port) = 1;
142 spin_unlock_irqrestore(&port->lock, flags);
143 }
144
s3c24xx_serial_rx_disable(struct uart_port * port)145 static void s3c24xx_serial_rx_disable(struct uart_port *port)
146 {
147 unsigned long flags;
148 unsigned int ucon;
149
150 spin_lock_irqsave(&port->lock, flags);
151
152 ucon = rd_regl(port, S3C2410_UCON);
153 ucon &= ~S3C2410_UCON_RXIRQMODE;
154 wr_regl(port, S3C2410_UCON, ucon);
155
156 rx_enabled(port) = 0;
157 spin_unlock_irqrestore(&port->lock, flags);
158 }
159
s3c24xx_serial_stop_tx(struct uart_port * port)160 static void s3c24xx_serial_stop_tx(struct uart_port *port)
161 {
162 struct s3c24xx_uart_port *ourport = to_ourport(port);
163 struct s3c24xx_uart_dma *dma = ourport->dma;
164 struct circ_buf *xmit = &port->state->xmit;
165 struct dma_tx_state state;
166 int count;
167
168 if (!tx_enabled(port))
169 return;
170
171 if (s3c24xx_serial_has_interrupt_mask(port))
172 __set_bit(S3C64XX_UINTM_TXD,
173 portaddrl(port, S3C64XX_UINTM));
174 else
175 disable_irq_nosync(ourport->tx_irq);
176
177 if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {
178 dmaengine_pause(dma->tx_chan);
179 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
180 dmaengine_terminate_all(dma->tx_chan);
181 dma_sync_single_for_cpu(ourport->port.dev,
182 dma->tx_transfer_addr, dma->tx_size, DMA_TO_DEVICE);
183 async_tx_ack(dma->tx_desc);
184 count = dma->tx_bytes_requested - state.residue;
185 xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
186 port->icount.tx += count;
187 }
188
189 tx_enabled(port) = 0;
190 ourport->tx_in_progress = 0;
191
192 if (port->flags & UPF_CONS_FLOW)
193 s3c24xx_serial_rx_enable(port);
194
195 ourport->tx_mode = 0;
196 }
197
198 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
199
s3c24xx_serial_tx_dma_complete(void * args)200 static void s3c24xx_serial_tx_dma_complete(void *args)
201 {
202 struct s3c24xx_uart_port *ourport = args;
203 struct uart_port *port = &ourport->port;
204 struct circ_buf *xmit = &port->state->xmit;
205 struct s3c24xx_uart_dma *dma = ourport->dma;
206 struct dma_tx_state state;
207 unsigned long flags;
208 int count;
209
210
211 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
212 count = dma->tx_bytes_requested - state.residue;
213 async_tx_ack(dma->tx_desc);
214
215 dma_sync_single_for_cpu(ourport->port.dev, dma->tx_transfer_addr,
216 dma->tx_size, DMA_TO_DEVICE);
217
218 spin_lock_irqsave(&port->lock, flags);
219
220 xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
221 port->icount.tx += count;
222 ourport->tx_in_progress = 0;
223
224 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
225 uart_write_wakeup(port);
226
227 s3c24xx_serial_start_next_tx(ourport);
228 spin_unlock_irqrestore(&port->lock, flags);
229 }
230
enable_tx_dma(struct s3c24xx_uart_port * ourport)231 static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
232 {
233 struct uart_port *port = &ourport->port;
234 u32 ucon;
235
236 /* Mask Tx interrupt */
237 if (s3c24xx_serial_has_interrupt_mask(port))
238 __set_bit(S3C64XX_UINTM_TXD,
239 portaddrl(port, S3C64XX_UINTM));
240 else
241 disable_irq_nosync(ourport->tx_irq);
242
243 /* Enable tx dma mode */
244 ucon = rd_regl(port, S3C2410_UCON);
245 ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
246 ucon |= (dma_get_cache_alignment() >= 16) ?
247 S3C64XX_UCON_TXBURST_16 : S3C64XX_UCON_TXBURST_1;
248 ucon |= S3C64XX_UCON_TXMODE_DMA;
249 wr_regl(port, S3C2410_UCON, ucon);
250
251 ourport->tx_mode = S3C24XX_TX_DMA;
252 }
253
enable_tx_pio(struct s3c24xx_uart_port * ourport)254 static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
255 {
256 struct uart_port *port = &ourport->port;
257 u32 ucon, ufcon;
258
259 /* Set ufcon txtrig */
260 ourport->tx_in_progress = S3C24XX_TX_PIO;
261 ufcon = rd_regl(port, S3C2410_UFCON);
262 wr_regl(port, S3C2410_UFCON, ufcon);
263
264 /* Enable tx pio mode */
265 ucon = rd_regl(port, S3C2410_UCON);
266 ucon &= ~(S3C64XX_UCON_TXMODE_MASK);
267 ucon |= S3C64XX_UCON_TXMODE_CPU;
268 wr_regl(port, S3C2410_UCON, ucon);
269
270 /* Unmask Tx interrupt */
271 if (s3c24xx_serial_has_interrupt_mask(port))
272 __clear_bit(S3C64XX_UINTM_TXD,
273 portaddrl(port, S3C64XX_UINTM));
274 else
275 enable_irq(ourport->tx_irq);
276
277 ourport->tx_mode = S3C24XX_TX_PIO;
278 }
279
s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port * ourport)280 static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)
281 {
282 if (ourport->tx_mode != S3C24XX_TX_PIO)
283 enable_tx_pio(ourport);
284 }
285
s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port * ourport,unsigned int count)286 static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
287 unsigned int count)
288 {
289 struct uart_port *port = &ourport->port;
290 struct circ_buf *xmit = &port->state->xmit;
291 struct s3c24xx_uart_dma *dma = ourport->dma;
292
293
294 if (ourport->tx_mode != S3C24XX_TX_DMA)
295 enable_tx_dma(ourport);
296
297 dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
298 dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
299
300 dma_sync_single_for_device(ourport->port.dev, dma->tx_transfer_addr,
301 dma->tx_size, DMA_TO_DEVICE);
302
303 dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,
304 dma->tx_transfer_addr, dma->tx_size,
305 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
306 if (!dma->tx_desc) {
307 dev_err(ourport->port.dev, "Unable to get desc for Tx\n");
308 return -EIO;
309 }
310
311 dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;
312 dma->tx_desc->callback_param = ourport;
313 dma->tx_bytes_requested = dma->tx_size;
314
315 ourport->tx_in_progress = S3C24XX_TX_DMA;
316 dma->tx_cookie = dmaengine_submit(dma->tx_desc);
317 dma_async_issue_pending(dma->tx_chan);
318 return 0;
319 }
320
s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port * ourport)321 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
322 {
323 struct uart_port *port = &ourport->port;
324 struct circ_buf *xmit = &port->state->xmit;
325 unsigned long count;
326
327 /* Get data size up to the end of buffer */
328 count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
329
330 if (!count) {
331 s3c24xx_serial_stop_tx(port);
332 return;
333 }
334
335 if (!ourport->dma || !ourport->dma->tx_chan ||
336 count < ourport->min_dma_size ||
337 xmit->tail & (dma_get_cache_alignment() - 1))
338 s3c24xx_serial_start_tx_pio(ourport);
339 else
340 s3c24xx_serial_start_tx_dma(ourport, count);
341 }
342
s3c24xx_serial_start_tx(struct uart_port * port)343 static void s3c24xx_serial_start_tx(struct uart_port *port)
344 {
345 struct s3c24xx_uart_port *ourport = to_ourport(port);
346 struct circ_buf *xmit = &port->state->xmit;
347
348 if (!tx_enabled(port)) {
349 if (port->flags & UPF_CONS_FLOW)
350 s3c24xx_serial_rx_disable(port);
351
352 tx_enabled(port) = 1;
353 if (!ourport->dma || !ourport->dma->tx_chan)
354 s3c24xx_serial_start_tx_pio(ourport);
355 }
356
357 if (ourport->dma && ourport->dma->tx_chan) {
358 if (!uart_circ_empty(xmit) && !ourport->tx_in_progress)
359 s3c24xx_serial_start_next_tx(ourport);
360 }
361 }
362
s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port * ourport,struct tty_port * tty,int count)363 static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,
364 struct tty_port *tty, int count)
365 {
366 struct s3c24xx_uart_dma *dma = ourport->dma;
367 int copied;
368
369 if (!count)
370 return;
371
372 dma_sync_single_for_cpu(ourport->port.dev, dma->rx_addr,
373 dma->rx_size, DMA_FROM_DEVICE);
374
375 ourport->port.icount.rx += count;
376 if (!tty) {
377 dev_err(ourport->port.dev, "No tty port\n");
378 return;
379 }
380 copied = tty_insert_flip_string(tty,
381 ((unsigned char *)(ourport->dma->rx_buf)), count);
382 if (copied != count) {
383 WARN_ON(1);
384 dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");
385 }
386 }
387
s3c24xx_serial_stop_rx(struct uart_port * port)388 static void s3c24xx_serial_stop_rx(struct uart_port *port)
389 {
390 struct s3c24xx_uart_port *ourport = to_ourport(port);
391 struct s3c24xx_uart_dma *dma = ourport->dma;
392 struct tty_port *t = &port->state->port;
393 struct dma_tx_state state;
394 enum dma_status dma_status;
395 unsigned int received;
396
397 if (rx_enabled(port)) {
398 dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
399 if (s3c24xx_serial_has_interrupt_mask(port))
400 __set_bit(S3C64XX_UINTM_RXD,
401 portaddrl(port, S3C64XX_UINTM));
402 else
403 disable_irq_nosync(ourport->rx_irq);
404 rx_enabled(port) = 0;
405 }
406 if (dma && dma->rx_chan) {
407 dmaengine_pause(dma->tx_chan);
408 dma_status = dmaengine_tx_status(dma->rx_chan,
409 dma->rx_cookie, &state);
410 if (dma_status == DMA_IN_PROGRESS ||
411 dma_status == DMA_PAUSED) {
412 received = dma->rx_bytes_requested - state.residue;
413 dmaengine_terminate_all(dma->rx_chan);
414 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
415 }
416 }
417 }
418
419 static inline struct s3c24xx_uart_info
s3c24xx_port_to_info(struct uart_port * port)420 *s3c24xx_port_to_info(struct uart_port *port)
421 {
422 return to_ourport(port)->info;
423 }
424
425 static inline struct s3c2410_uartcfg
s3c24xx_port_to_cfg(struct uart_port * port)426 *s3c24xx_port_to_cfg(struct uart_port *port)
427 {
428 struct s3c24xx_uart_port *ourport;
429
430 if (port->dev == NULL)
431 return NULL;
432
433 ourport = container_of(port, struct s3c24xx_uart_port, port);
434 return ourport->cfg;
435 }
436
s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port * ourport,unsigned long ufstat)437 static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
438 unsigned long ufstat)
439 {
440 struct s3c24xx_uart_info *info = ourport->info;
441
442 if (ufstat & info->rx_fifofull)
443 return ourport->port.fifosize;
444
445 return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
446 }
447
448 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
s3c24xx_serial_rx_dma_complete(void * args)449 static void s3c24xx_serial_rx_dma_complete(void *args)
450 {
451 struct s3c24xx_uart_port *ourport = args;
452 struct uart_port *port = &ourport->port;
453
454 struct s3c24xx_uart_dma *dma = ourport->dma;
455 struct tty_port *t = &port->state->port;
456 struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
457
458 struct dma_tx_state state;
459 unsigned long flags;
460 int received;
461
462 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
463 received = dma->rx_bytes_requested - state.residue;
464 async_tx_ack(dma->rx_desc);
465
466 spin_lock_irqsave(&port->lock, flags);
467
468 if (received)
469 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
470
471 if (tty) {
472 tty_flip_buffer_push(t);
473 tty_kref_put(tty);
474 }
475
476 s3c64xx_start_rx_dma(ourport);
477
478 spin_unlock_irqrestore(&port->lock, flags);
479 }
480
s3c64xx_start_rx_dma(struct s3c24xx_uart_port * ourport)481 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)
482 {
483 struct s3c24xx_uart_dma *dma = ourport->dma;
484
485 dma_sync_single_for_device(ourport->port.dev, dma->rx_addr,
486 dma->rx_size, DMA_FROM_DEVICE);
487
488 dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,
489 dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,
490 DMA_PREP_INTERRUPT);
491 if (!dma->rx_desc) {
492 dev_err(ourport->port.dev, "Unable to get desc for Rx\n");
493 return;
494 }
495
496 dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;
497 dma->rx_desc->callback_param = ourport;
498 dma->rx_bytes_requested = dma->rx_size;
499
500 dma->rx_cookie = dmaengine_submit(dma->rx_desc);
501 dma_async_issue_pending(dma->rx_chan);
502 }
503
504 /* ? - where has parity gone?? */
505 #define S3C2410_UERSTAT_PARITY (0x1000)
506
enable_rx_dma(struct s3c24xx_uart_port * ourport)507 static void enable_rx_dma(struct s3c24xx_uart_port *ourport)
508 {
509 struct uart_port *port = &ourport->port;
510 unsigned int ucon;
511
512 /* set Rx mode to DMA mode */
513 ucon = rd_regl(port, S3C2410_UCON);
514 ucon &= ~(S3C64XX_UCON_RXBURST_MASK |
515 S3C64XX_UCON_TIMEOUT_MASK |
516 S3C64XX_UCON_EMPTYINT_EN |
517 S3C64XX_UCON_DMASUS_EN |
518 S3C64XX_UCON_TIMEOUT_EN |
519 S3C64XX_UCON_RXMODE_MASK);
520 ucon |= S3C64XX_UCON_RXBURST_16 |
521 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
522 S3C64XX_UCON_EMPTYINT_EN |
523 S3C64XX_UCON_TIMEOUT_EN |
524 S3C64XX_UCON_RXMODE_DMA;
525 wr_regl(port, S3C2410_UCON, ucon);
526
527 ourport->rx_mode = S3C24XX_RX_DMA;
528 }
529
enable_rx_pio(struct s3c24xx_uart_port * ourport)530 static void enable_rx_pio(struct s3c24xx_uart_port *ourport)
531 {
532 struct uart_port *port = &ourport->port;
533 unsigned int ucon;
534
535 /* set Rx mode to DMA mode */
536 ucon = rd_regl(port, S3C2410_UCON);
537 ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |
538 S3C64XX_UCON_EMPTYINT_EN |
539 S3C64XX_UCON_DMASUS_EN |
540 S3C64XX_UCON_TIMEOUT_EN |
541 S3C64XX_UCON_RXMODE_MASK);
542 ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
543 S3C64XX_UCON_TIMEOUT_EN |
544 S3C64XX_UCON_RXMODE_CPU;
545 wr_regl(port, S3C2410_UCON, ucon);
546
547 ourport->rx_mode = S3C24XX_RX_PIO;
548 }
549
550 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
551
s3c24xx_serial_rx_chars_dma(void * dev_id)552 static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
553 {
554 unsigned int utrstat, ufstat, received;
555 struct s3c24xx_uart_port *ourport = dev_id;
556 struct uart_port *port = &ourport->port;
557 struct s3c24xx_uart_dma *dma = ourport->dma;
558 struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
559 struct tty_port *t = &port->state->port;
560 unsigned long flags;
561 struct dma_tx_state state;
562
563 utrstat = rd_regl(port, S3C2410_UTRSTAT);
564 ufstat = rd_regl(port, S3C2410_UFSTAT);
565
566 spin_lock_irqsave(&port->lock, flags);
567
568 if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
569 s3c64xx_start_rx_dma(ourport);
570 if (ourport->rx_mode == S3C24XX_RX_PIO)
571 enable_rx_dma(ourport);
572 goto finish;
573 }
574
575 if (ourport->rx_mode == S3C24XX_RX_DMA) {
576 dmaengine_pause(dma->rx_chan);
577 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
578 dmaengine_terminate_all(dma->rx_chan);
579 received = dma->rx_bytes_requested - state.residue;
580 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
581
582 enable_rx_pio(ourport);
583 }
584
585 s3c24xx_serial_rx_drain_fifo(ourport);
586
587 if (tty) {
588 tty_flip_buffer_push(t);
589 tty_kref_put(tty);
590 }
591
592 wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
593
594 finish:
595 spin_unlock_irqrestore(&port->lock, flags);
596
597 return IRQ_HANDLED;
598 }
599
s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port * ourport)600 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
601 {
602 struct uart_port *port = &ourport->port;
603 unsigned int ufcon, ch, flag, ufstat, uerstat;
604 int max_count = port->fifosize;
605
606 while (max_count-- > 0) {
607 ufcon = rd_regl(port, S3C2410_UFCON);
608 ufstat = rd_regl(port, S3C2410_UFSTAT);
609
610 if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
611 break;
612
613 uerstat = rd_regl(port, S3C2410_UERSTAT);
614 ch = rd_regb(port, S3C2410_URXH);
615
616 if (port->flags & UPF_CONS_FLOW) {
617 int txe = s3c24xx_serial_txempty_nofifo(port);
618
619 if (rx_enabled(port)) {
620 if (!txe) {
621 rx_enabled(port) = 0;
622 continue;
623 }
624 } else {
625 if (txe) {
626 ufcon |= S3C2410_UFCON_RESETRX;
627 wr_regl(port, S3C2410_UFCON, ufcon);
628 rx_enabled(port) = 1;
629 return;
630 }
631 continue;
632 }
633 }
634
635 /* insert the character into the buffer */
636
637 flag = TTY_NORMAL;
638 port->icount.rx++;
639
640 if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
641 dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
642 ch, uerstat);
643
644 /* check for break */
645 if (uerstat & S3C2410_UERSTAT_BREAK) {
646 dbg("break!\n");
647 port->icount.brk++;
648 if (uart_handle_break(port))
649 continue; /* Ignore character */
650 }
651
652 if (uerstat & S3C2410_UERSTAT_FRAME)
653 port->icount.frame++;
654 if (uerstat & S3C2410_UERSTAT_OVERRUN)
655 port->icount.overrun++;
656
657 uerstat &= port->read_status_mask;
658
659 if (uerstat & S3C2410_UERSTAT_BREAK)
660 flag = TTY_BREAK;
661 else if (uerstat & S3C2410_UERSTAT_PARITY)
662 flag = TTY_PARITY;
663 else if (uerstat & (S3C2410_UERSTAT_FRAME |
664 S3C2410_UERSTAT_OVERRUN))
665 flag = TTY_FRAME;
666 }
667
668 if (uart_handle_sysrq_char(port, ch))
669 continue; /* Ignore character */
670
671 uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
672 ch, flag);
673 }
674
675 tty_flip_buffer_push(&port->state->port);
676 }
677
s3c24xx_serial_rx_chars_pio(void * dev_id)678 static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
679 {
680 struct s3c24xx_uart_port *ourport = dev_id;
681 struct uart_port *port = &ourport->port;
682 unsigned long flags;
683
684 spin_lock_irqsave(&port->lock, flags);
685 s3c24xx_serial_rx_drain_fifo(ourport);
686 spin_unlock_irqrestore(&port->lock, flags);
687
688 return IRQ_HANDLED;
689 }
690
691
s3c24xx_serial_rx_chars(int irq,void * dev_id)692 static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id)
693 {
694 struct s3c24xx_uart_port *ourport = dev_id;
695
696 if (ourport->dma && ourport->dma->rx_chan)
697 return s3c24xx_serial_rx_chars_dma(dev_id);
698 return s3c24xx_serial_rx_chars_pio(dev_id);
699 }
700
s3c24xx_serial_tx_chars(int irq,void * id)701 static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
702 {
703 struct s3c24xx_uart_port *ourport = id;
704 struct uart_port *port = &ourport->port;
705 struct circ_buf *xmit = &port->state->xmit;
706 unsigned long flags;
707 int count, dma_count = 0;
708
709 spin_lock_irqsave(&port->lock, flags);
710
711 count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
712
713 if (ourport->dma && ourport->dma->tx_chan &&
714 count >= ourport->min_dma_size) {
715 int align = dma_get_cache_alignment() -
716 (xmit->tail & (dma_get_cache_alignment() - 1));
717 if (count-align >= ourport->min_dma_size) {
718 dma_count = count-align;
719 count = align;
720 }
721 }
722
723 if (port->x_char) {
724 wr_regb(port, S3C2410_UTXH, port->x_char);
725 port->icount.tx++;
726 port->x_char = 0;
727 goto out;
728 }
729
730 /* if there isn't anything more to transmit, or the uart is now
731 * stopped, disable the uart and exit
732 */
733
734 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
735 s3c24xx_serial_stop_tx(port);
736 goto out;
737 }
738
739 /* try and drain the buffer... */
740
741 if (count > port->fifosize) {
742 count = port->fifosize;
743 dma_count = 0;
744 }
745
746 while (!uart_circ_empty(xmit) && count > 0) {
747 if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
748 break;
749
750 wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
751 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
752 port->icount.tx++;
753 count--;
754 }
755
756 if (!count && dma_count) {
757 s3c24xx_serial_start_tx_dma(ourport, dma_count);
758 goto out;
759 }
760
761 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
762 spin_unlock(&port->lock);
763 uart_write_wakeup(port);
764 spin_lock(&port->lock);
765 }
766
767 if (uart_circ_empty(xmit))
768 s3c24xx_serial_stop_tx(port);
769
770 out:
771 spin_unlock_irqrestore(&port->lock, flags);
772 return IRQ_HANDLED;
773 }
774
775 /* interrupt handler for s3c64xx and later SoC's.*/
s3c64xx_serial_handle_irq(int irq,void * id)776 static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)
777 {
778 struct s3c24xx_uart_port *ourport = id;
779 struct uart_port *port = &ourport->port;
780 unsigned int pend = rd_regl(port, S3C64XX_UINTP);
781 irqreturn_t ret = IRQ_HANDLED;
782
783 if (pend & S3C64XX_UINTM_RXD_MSK) {
784 ret = s3c24xx_serial_rx_chars(irq, id);
785 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);
786 }
787 if (pend & S3C64XX_UINTM_TXD_MSK) {
788 ret = s3c24xx_serial_tx_chars(irq, id);
789 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);
790 }
791 return ret;
792 }
793
s3c24xx_serial_tx_empty(struct uart_port * port)794 static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
795 {
796 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
797 unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
798 unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
799
800 if (ufcon & S3C2410_UFCON_FIFOMODE) {
801 if ((ufstat & info->tx_fifomask) != 0 ||
802 (ufstat & info->tx_fifofull))
803 return 0;
804
805 return 1;
806 }
807
808 return s3c24xx_serial_txempty_nofifo(port);
809 }
810
811 /* no modem control lines */
s3c24xx_serial_get_mctrl(struct uart_port * port)812 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
813 {
814 unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
815
816 if (umstat & S3C2410_UMSTAT_CTS)
817 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
818 else
819 return TIOCM_CAR | TIOCM_DSR;
820 }
821
s3c24xx_serial_set_mctrl(struct uart_port * port,unsigned int mctrl)822 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
823 {
824 unsigned int umcon = rd_regl(port, S3C2410_UMCON);
825
826 if (mctrl & TIOCM_RTS)
827 umcon |= S3C2410_UMCOM_RTS_LOW;
828 else
829 umcon &= ~S3C2410_UMCOM_RTS_LOW;
830
831 wr_regl(port, S3C2410_UMCON, umcon);
832 }
833
s3c24xx_serial_break_ctl(struct uart_port * port,int break_state)834 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
835 {
836 unsigned long flags;
837 unsigned int ucon;
838
839 spin_lock_irqsave(&port->lock, flags);
840
841 ucon = rd_regl(port, S3C2410_UCON);
842
843 if (break_state)
844 ucon |= S3C2410_UCON_SBREAK;
845 else
846 ucon &= ~S3C2410_UCON_SBREAK;
847
848 wr_regl(port, S3C2410_UCON, ucon);
849
850 spin_unlock_irqrestore(&port->lock, flags);
851 }
852
s3c24xx_serial_request_dma(struct s3c24xx_uart_port * p)853 static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
854 {
855 struct s3c24xx_uart_dma *dma = p->dma;
856 dma_cap_mask_t mask;
857 unsigned long flags;
858
859 /* Default slave configuration parameters */
860 dma->rx_conf.direction = DMA_DEV_TO_MEM;
861 dma->rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
862 dma->rx_conf.src_addr = p->port.mapbase + S3C2410_URXH;
863 dma->rx_conf.src_maxburst = 16;
864
865 dma->tx_conf.direction = DMA_MEM_TO_DEV;
866 dma->tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
867 dma->tx_conf.dst_addr = p->port.mapbase + S3C2410_UTXH;
868 if (dma_get_cache_alignment() >= 16)
869 dma->tx_conf.dst_maxburst = 16;
870 else
871 dma->tx_conf.dst_maxburst = 1;
872
873 dma_cap_zero(mask);
874 dma_cap_set(DMA_SLAVE, mask);
875
876 dma->rx_chan = dma_request_slave_channel_compat(mask, dma->fn,
877 dma->rx_param, p->port.dev, "rx");
878 if (!dma->rx_chan)
879 return -ENODEV;
880
881 dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);
882
883 dma->tx_chan = dma_request_slave_channel_compat(mask, dma->fn,
884 dma->tx_param, p->port.dev, "tx");
885 if (!dma->tx_chan) {
886 dma_release_channel(dma->rx_chan);
887 return -ENODEV;
888 }
889
890 dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
891
892 /* RX buffer */
893 dma->rx_size = PAGE_SIZE;
894
895 dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
896
897 if (!dma->rx_buf) {
898 dma_release_channel(dma->rx_chan);
899 dma_release_channel(dma->tx_chan);
900 return -ENOMEM;
901 }
902
903 dma->rx_addr = dma_map_single(dma->rx_chan->device->dev, dma->rx_buf,
904 dma->rx_size, DMA_FROM_DEVICE);
905
906 spin_lock_irqsave(&p->port.lock, flags);
907
908 /* TX buffer */
909 dma->tx_addr = dma_map_single(dma->tx_chan->device->dev,
910 p->port.state->xmit.buf,
911 UART_XMIT_SIZE, DMA_TO_DEVICE);
912
913 spin_unlock_irqrestore(&p->port.lock, flags);
914
915 return 0;
916 }
917
s3c24xx_serial_release_dma(struct s3c24xx_uart_port * p)918 static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)
919 {
920 struct s3c24xx_uart_dma *dma = p->dma;
921
922 if (dma->rx_chan) {
923 dmaengine_terminate_all(dma->rx_chan);
924 dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr,
925 dma->rx_size, DMA_FROM_DEVICE);
926 kfree(dma->rx_buf);
927 dma_release_channel(dma->rx_chan);
928 dma->rx_chan = NULL;
929 }
930
931 if (dma->tx_chan) {
932 dmaengine_terminate_all(dma->tx_chan);
933 dma_unmap_single(dma->tx_chan->device->dev, dma->tx_addr,
934 UART_XMIT_SIZE, DMA_TO_DEVICE);
935 dma_release_channel(dma->tx_chan);
936 dma->tx_chan = NULL;
937 }
938 }
939
s3c24xx_serial_shutdown(struct uart_port * port)940 static void s3c24xx_serial_shutdown(struct uart_port *port)
941 {
942 struct s3c24xx_uart_port *ourport = to_ourport(port);
943
944 if (ourport->tx_claimed) {
945 if (!s3c24xx_serial_has_interrupt_mask(port))
946 free_irq(ourport->tx_irq, ourport);
947 tx_enabled(port) = 0;
948 ourport->tx_claimed = 0;
949 ourport->tx_mode = 0;
950 }
951
952 if (ourport->rx_claimed) {
953 if (!s3c24xx_serial_has_interrupt_mask(port))
954 free_irq(ourport->rx_irq, ourport);
955 ourport->rx_claimed = 0;
956 rx_enabled(port) = 0;
957 }
958
959 /* Clear pending interrupts and mask all interrupts */
960 if (s3c24xx_serial_has_interrupt_mask(port)) {
961 free_irq(port->irq, ourport);
962
963 wr_regl(port, S3C64XX_UINTP, 0xf);
964 wr_regl(port, S3C64XX_UINTM, 0xf);
965 }
966
967 if (ourport->dma)
968 s3c24xx_serial_release_dma(ourport);
969
970 ourport->tx_in_progress = 0;
971 }
972
s3c24xx_serial_startup(struct uart_port * port)973 static int s3c24xx_serial_startup(struct uart_port *port)
974 {
975 struct s3c24xx_uart_port *ourport = to_ourport(port);
976 int ret;
977
978 dbg("s3c24xx_serial_startup: port=%p (%08llx,%p)\n",
979 port, (unsigned long long)port->mapbase, port->membase);
980
981 rx_enabled(port) = 1;
982
983 ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_chars, 0,
984 s3c24xx_serial_portname(port), ourport);
985
986 if (ret != 0) {
987 dev_err(port->dev, "cannot get irq %d\n", ourport->rx_irq);
988 return ret;
989 }
990
991 ourport->rx_claimed = 1;
992
993 dbg("requesting tx irq...\n");
994
995 tx_enabled(port) = 1;
996
997 ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_chars, 0,
998 s3c24xx_serial_portname(port), ourport);
999
1000 if (ret) {
1001 dev_err(port->dev, "cannot get irq %d\n", ourport->tx_irq);
1002 goto err;
1003 }
1004
1005 ourport->tx_claimed = 1;
1006
1007 dbg("s3c24xx_serial_startup ok\n");
1008
1009 /* the port reset code should have done the correct
1010 * register setup for the port controls */
1011
1012 return ret;
1013
1014 err:
1015 s3c24xx_serial_shutdown(port);
1016 return ret;
1017 }
1018
s3c64xx_serial_startup(struct uart_port * port)1019 static int s3c64xx_serial_startup(struct uart_port *port)
1020 {
1021 struct s3c24xx_uart_port *ourport = to_ourport(port);
1022 unsigned long flags;
1023 unsigned int ufcon;
1024 int ret;
1025
1026 dbg("s3c64xx_serial_startup: port=%p (%08llx,%p)\n",
1027 port, (unsigned long long)port->mapbase, port->membase);
1028
1029 wr_regl(port, S3C64XX_UINTM, 0xf);
1030 if (ourport->dma) {
1031 ret = s3c24xx_serial_request_dma(ourport);
1032 if (ret < 0) {
1033 dev_warn(port->dev, "DMA request failed\n");
1034 return ret;
1035 }
1036 }
1037
1038 ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
1039 s3c24xx_serial_portname(port), ourport);
1040 if (ret) {
1041 dev_err(port->dev, "cannot get irq %d\n", port->irq);
1042 return ret;
1043 }
1044
1045 /* For compatibility with s3c24xx Soc's */
1046 rx_enabled(port) = 1;
1047 ourport->rx_claimed = 1;
1048 tx_enabled(port) = 0;
1049 ourport->tx_claimed = 1;
1050
1051 spin_lock_irqsave(&port->lock, flags);
1052
1053 ufcon = rd_regl(port, S3C2410_UFCON);
1054 ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
1055 if (!uart_console(port))
1056 ufcon |= S3C2410_UFCON_RESETTX;
1057 wr_regl(port, S3C2410_UFCON, ufcon);
1058
1059 enable_rx_pio(ourport);
1060
1061 spin_unlock_irqrestore(&port->lock, flags);
1062
1063 /* Enable Rx Interrupt */
1064 __clear_bit(S3C64XX_UINTM_RXD, portaddrl(port, S3C64XX_UINTM));
1065
1066 dbg("s3c64xx_serial_startup ok\n");
1067 return ret;
1068 }
1069
1070 /* power power management control */
1071
s3c24xx_serial_pm(struct uart_port * port,unsigned int level,unsigned int old)1072 static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
1073 unsigned int old)
1074 {
1075 struct s3c24xx_uart_port *ourport = to_ourport(port);
1076 int timeout = 10000;
1077
1078 ourport->pm_level = level;
1079
1080 switch (level) {
1081 case 3:
1082 while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
1083 udelay(100);
1084
1085 if (!IS_ERR(ourport->baudclk))
1086 clk_disable_unprepare(ourport->baudclk);
1087
1088 clk_disable_unprepare(ourport->clk);
1089 break;
1090
1091 case 0:
1092 clk_prepare_enable(ourport->clk);
1093
1094 if (!IS_ERR(ourport->baudclk))
1095 clk_prepare_enable(ourport->baudclk);
1096
1097 break;
1098 default:
1099 dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);
1100 }
1101 }
1102
1103 /* baud rate calculation
1104 *
1105 * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
1106 * of different sources, including the peripheral clock ("pclk") and an
1107 * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
1108 * with a programmable extra divisor.
1109 *
1110 * The following code goes through the clock sources, and calculates the
1111 * baud clocks (and the resultant actual baud rates) and then tries to
1112 * pick the closest one and select that.
1113 *
1114 */
1115
1116 #define MAX_CLK_NAME_LENGTH 15
1117
s3c24xx_serial_getsource(struct uart_port * port)1118 static inline int s3c24xx_serial_getsource(struct uart_port *port)
1119 {
1120 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1121 unsigned int ucon;
1122
1123 if (info->num_clks == 1)
1124 return 0;
1125
1126 ucon = rd_regl(port, S3C2410_UCON);
1127 ucon &= info->clksel_mask;
1128 return ucon >> info->clksel_shift;
1129 }
1130
s3c24xx_serial_setsource(struct uart_port * port,unsigned int clk_sel)1131 static void s3c24xx_serial_setsource(struct uart_port *port,
1132 unsigned int clk_sel)
1133 {
1134 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1135 unsigned int ucon;
1136
1137 if (info->num_clks == 1)
1138 return;
1139
1140 ucon = rd_regl(port, S3C2410_UCON);
1141 if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel)
1142 return;
1143
1144 ucon &= ~info->clksel_mask;
1145 ucon |= clk_sel << info->clksel_shift;
1146 wr_regl(port, S3C2410_UCON, ucon);
1147 }
1148
s3c24xx_serial_getclk(struct s3c24xx_uart_port * ourport,unsigned int req_baud,struct clk ** best_clk,unsigned int * clk_num)1149 static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
1150 unsigned int req_baud, struct clk **best_clk,
1151 unsigned int *clk_num)
1152 {
1153 struct s3c24xx_uart_info *info = ourport->info;
1154 struct clk *clk;
1155 unsigned long rate;
1156 unsigned int cnt, baud, quot, clk_sel, best_quot = 0;
1157 char clkname[MAX_CLK_NAME_LENGTH];
1158 int calc_deviation, deviation = (1 << 30) - 1;
1159
1160 clk_sel = (ourport->cfg->clk_sel) ? ourport->cfg->clk_sel :
1161 ourport->info->def_clk_sel;
1162 for (cnt = 0; cnt < info->num_clks; cnt++) {
1163 if (!(clk_sel & (1 << cnt)))
1164 continue;
1165
1166 sprintf(clkname, "clk_uart_baud%d", cnt);
1167 clk = clk_get(ourport->port.dev, clkname);
1168 if (IS_ERR(clk))
1169 continue;
1170
1171 rate = clk_get_rate(clk);
1172 if (!rate)
1173 continue;
1174
1175 if (ourport->info->has_divslot) {
1176 unsigned long div = rate / req_baud;
1177
1178 /* The UDIVSLOT register on the newer UARTs allows us to
1179 * get a divisor adjustment of 1/16th on the baud clock.
1180 *
1181 * We don't keep the UDIVSLOT value (the 16ths we
1182 * calculated by not multiplying the baud by 16) as it
1183 * is easy enough to recalculate.
1184 */
1185
1186 quot = div / 16;
1187 baud = rate / div;
1188 } else {
1189 quot = (rate + (8 * req_baud)) / (16 * req_baud);
1190 baud = rate / (quot * 16);
1191 }
1192 quot--;
1193
1194 calc_deviation = req_baud - baud;
1195 if (calc_deviation < 0)
1196 calc_deviation = -calc_deviation;
1197
1198 if (calc_deviation < deviation) {
1199 *best_clk = clk;
1200 best_quot = quot;
1201 *clk_num = cnt;
1202 deviation = calc_deviation;
1203 }
1204 }
1205
1206 return best_quot;
1207 }
1208
1209 /* udivslot_table[]
1210 *
1211 * This table takes the fractional value of the baud divisor and gives
1212 * the recommended setting for the UDIVSLOT register.
1213 */
1214 static u16 udivslot_table[16] = {
1215 [0] = 0x0000,
1216 [1] = 0x0080,
1217 [2] = 0x0808,
1218 [3] = 0x0888,
1219 [4] = 0x2222,
1220 [5] = 0x4924,
1221 [6] = 0x4A52,
1222 [7] = 0x54AA,
1223 [8] = 0x5555,
1224 [9] = 0xD555,
1225 [10] = 0xD5D5,
1226 [11] = 0xDDD5,
1227 [12] = 0xDDDD,
1228 [13] = 0xDFDD,
1229 [14] = 0xDFDF,
1230 [15] = 0xFFDF,
1231 };
1232
s3c24xx_serial_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)1233 static void s3c24xx_serial_set_termios(struct uart_port *port,
1234 struct ktermios *termios,
1235 struct ktermios *old)
1236 {
1237 struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
1238 struct s3c24xx_uart_port *ourport = to_ourport(port);
1239 struct clk *clk = ERR_PTR(-EINVAL);
1240 unsigned long flags;
1241 unsigned int baud, quot, clk_sel = 0;
1242 unsigned int ulcon;
1243 unsigned int umcon;
1244 unsigned int udivslot = 0;
1245
1246 /*
1247 * We don't support modem control lines.
1248 */
1249 termios->c_cflag &= ~(HUPCL | CMSPAR);
1250 termios->c_cflag |= CLOCAL;
1251
1252 /*
1253 * Ask the core to calculate the divisor for us.
1254 */
1255
1256 baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
1257 quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);
1258 if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
1259 quot = port->custom_divisor;
1260 if (IS_ERR(clk))
1261 return;
1262
1263 /* check to see if we need to change clock source */
1264
1265 if (ourport->baudclk != clk) {
1266 clk_prepare_enable(clk);
1267
1268 s3c24xx_serial_setsource(port, clk_sel);
1269
1270 if (!IS_ERR(ourport->baudclk)) {
1271 clk_disable_unprepare(ourport->baudclk);
1272 ourport->baudclk = ERR_PTR(-EINVAL);
1273 }
1274
1275 ourport->baudclk = clk;
1276 ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
1277 }
1278
1279 if (ourport->info->has_divslot) {
1280 unsigned int div = ourport->baudclk_rate / baud;
1281
1282 if (cfg->has_fracval) {
1283 udivslot = (div & 15);
1284 dbg("fracval = %04x\n", udivslot);
1285 } else {
1286 udivslot = udivslot_table[div & 15];
1287 dbg("udivslot = %04x (div %d)\n", udivslot, div & 15);
1288 }
1289 }
1290
1291 switch (termios->c_cflag & CSIZE) {
1292 case CS5:
1293 dbg("config: 5bits/char\n");
1294 ulcon = S3C2410_LCON_CS5;
1295 break;
1296 case CS6:
1297 dbg("config: 6bits/char\n");
1298 ulcon = S3C2410_LCON_CS6;
1299 break;
1300 case CS7:
1301 dbg("config: 7bits/char\n");
1302 ulcon = S3C2410_LCON_CS7;
1303 break;
1304 case CS8:
1305 default:
1306 dbg("config: 8bits/char\n");
1307 ulcon = S3C2410_LCON_CS8;
1308 break;
1309 }
1310
1311 /* preserve original lcon IR settings */
1312 ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
1313
1314 if (termios->c_cflag & CSTOPB)
1315 ulcon |= S3C2410_LCON_STOPB;
1316
1317 if (termios->c_cflag & PARENB) {
1318 if (termios->c_cflag & PARODD)
1319 ulcon |= S3C2410_LCON_PODD;
1320 else
1321 ulcon |= S3C2410_LCON_PEVEN;
1322 } else {
1323 ulcon |= S3C2410_LCON_PNONE;
1324 }
1325
1326 spin_lock_irqsave(&port->lock, flags);
1327
1328 dbg("setting ulcon to %08x, brddiv to %d, udivslot %08x\n",
1329 ulcon, quot, udivslot);
1330
1331 wr_regl(port, S3C2410_ULCON, ulcon);
1332 wr_regl(port, S3C2410_UBRDIV, quot);
1333
1334 umcon = rd_regl(port, S3C2410_UMCON);
1335 if (termios->c_cflag & CRTSCTS) {
1336 umcon |= S3C2410_UMCOM_AFC;
1337 /* Disable RTS when RX FIFO contains 63 bytes */
1338 umcon &= ~S3C2412_UMCON_AFC_8;
1339 } else {
1340 umcon &= ~S3C2410_UMCOM_AFC;
1341 }
1342 wr_regl(port, S3C2410_UMCON, umcon);
1343
1344 if (ourport->info->has_divslot)
1345 wr_regl(port, S3C2443_DIVSLOT, udivslot);
1346
1347 dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
1348 rd_regl(port, S3C2410_ULCON),
1349 rd_regl(port, S3C2410_UCON),
1350 rd_regl(port, S3C2410_UFCON));
1351
1352 /*
1353 * Update the per-port timeout.
1354 */
1355 uart_update_timeout(port, termios->c_cflag, baud);
1356
1357 /*
1358 * Which character status flags are we interested in?
1359 */
1360 port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
1361 if (termios->c_iflag & INPCK)
1362 port->read_status_mask |= S3C2410_UERSTAT_FRAME |
1363 S3C2410_UERSTAT_PARITY;
1364 /*
1365 * Which character status flags should we ignore?
1366 */
1367 port->ignore_status_mask = 0;
1368 if (termios->c_iflag & IGNPAR)
1369 port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
1370 if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
1371 port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
1372
1373 /*
1374 * Ignore all characters if CREAD is not set.
1375 */
1376 if ((termios->c_cflag & CREAD) == 0)
1377 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
1378
1379 spin_unlock_irqrestore(&port->lock, flags);
1380 }
1381
s3c24xx_serial_type(struct uart_port * port)1382 static const char *s3c24xx_serial_type(struct uart_port *port)
1383 {
1384 switch (port->type) {
1385 case PORT_S3C2410:
1386 return "S3C2410";
1387 case PORT_S3C2440:
1388 return "S3C2440";
1389 case PORT_S3C2412:
1390 return "S3C2412";
1391 case PORT_S3C6400:
1392 return "S3C6400/10";
1393 default:
1394 return NULL;
1395 }
1396 }
1397
1398 #define MAP_SIZE (0x100)
1399
s3c24xx_serial_release_port(struct uart_port * port)1400 static void s3c24xx_serial_release_port(struct uart_port *port)
1401 {
1402 release_mem_region(port->mapbase, MAP_SIZE);
1403 }
1404
s3c24xx_serial_request_port(struct uart_port * port)1405 static int s3c24xx_serial_request_port(struct uart_port *port)
1406 {
1407 const char *name = s3c24xx_serial_portname(port);
1408 return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY;
1409 }
1410
s3c24xx_serial_config_port(struct uart_port * port,int flags)1411 static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
1412 {
1413 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1414
1415 if (flags & UART_CONFIG_TYPE &&
1416 s3c24xx_serial_request_port(port) == 0)
1417 port->type = info->type;
1418 }
1419
1420 /*
1421 * verify the new serial_struct (for TIOCSSERIAL).
1422 */
1423 static int
s3c24xx_serial_verify_port(struct uart_port * port,struct serial_struct * ser)1424 s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
1425 {
1426 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1427
1428 if (ser->type != PORT_UNKNOWN && ser->type != info->type)
1429 return -EINVAL;
1430
1431 return 0;
1432 }
1433
1434
1435 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1436
1437 static struct console s3c24xx_serial_console;
1438
s3c24xx_serial_console_init(void)1439 static int __init s3c24xx_serial_console_init(void)
1440 {
1441 register_console(&s3c24xx_serial_console);
1442 return 0;
1443 }
1444 console_initcall(s3c24xx_serial_console_init);
1445
1446 #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
1447 #else
1448 #define S3C24XX_SERIAL_CONSOLE NULL
1449 #endif
1450
1451 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1452 static int s3c24xx_serial_get_poll_char(struct uart_port *port);
1453 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1454 unsigned char c);
1455 #endif
1456
1457 static struct uart_ops s3c24xx_serial_ops = {
1458 .pm = s3c24xx_serial_pm,
1459 .tx_empty = s3c24xx_serial_tx_empty,
1460 .get_mctrl = s3c24xx_serial_get_mctrl,
1461 .set_mctrl = s3c24xx_serial_set_mctrl,
1462 .stop_tx = s3c24xx_serial_stop_tx,
1463 .start_tx = s3c24xx_serial_start_tx,
1464 .stop_rx = s3c24xx_serial_stop_rx,
1465 .break_ctl = s3c24xx_serial_break_ctl,
1466 .startup = s3c24xx_serial_startup,
1467 .shutdown = s3c24xx_serial_shutdown,
1468 .set_termios = s3c24xx_serial_set_termios,
1469 .type = s3c24xx_serial_type,
1470 .release_port = s3c24xx_serial_release_port,
1471 .request_port = s3c24xx_serial_request_port,
1472 .config_port = s3c24xx_serial_config_port,
1473 .verify_port = s3c24xx_serial_verify_port,
1474 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1475 .poll_get_char = s3c24xx_serial_get_poll_char,
1476 .poll_put_char = s3c24xx_serial_put_poll_char,
1477 #endif
1478 };
1479
1480 static struct uart_driver s3c24xx_uart_drv = {
1481 .owner = THIS_MODULE,
1482 .driver_name = "s3c2410_serial",
1483 .nr = CONFIG_SERIAL_SAMSUNG_UARTS,
1484 .cons = S3C24XX_SERIAL_CONSOLE,
1485 .dev_name = S3C24XX_SERIAL_NAME,
1486 .major = S3C24XX_SERIAL_MAJOR,
1487 .minor = S3C24XX_SERIAL_MINOR,
1488 };
1489
1490 #define __PORT_LOCK_UNLOCKED(i) \
1491 __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[i].port.lock)
1492 static struct s3c24xx_uart_port
1493 s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS] = {
1494 [0] = {
1495 .port = {
1496 .lock = __PORT_LOCK_UNLOCKED(0),
1497 .iotype = UPIO_MEM,
1498 .uartclk = 0,
1499 .fifosize = 16,
1500 .ops = &s3c24xx_serial_ops,
1501 .flags = UPF_BOOT_AUTOCONF,
1502 .line = 0,
1503 }
1504 },
1505 [1] = {
1506 .port = {
1507 .lock = __PORT_LOCK_UNLOCKED(1),
1508 .iotype = UPIO_MEM,
1509 .uartclk = 0,
1510 .fifosize = 16,
1511 .ops = &s3c24xx_serial_ops,
1512 .flags = UPF_BOOT_AUTOCONF,
1513 .line = 1,
1514 }
1515 },
1516 #if CONFIG_SERIAL_SAMSUNG_UARTS > 2
1517
1518 [2] = {
1519 .port = {
1520 .lock = __PORT_LOCK_UNLOCKED(2),
1521 .iotype = UPIO_MEM,
1522 .uartclk = 0,
1523 .fifosize = 16,
1524 .ops = &s3c24xx_serial_ops,
1525 .flags = UPF_BOOT_AUTOCONF,
1526 .line = 2,
1527 }
1528 },
1529 #endif
1530 #if CONFIG_SERIAL_SAMSUNG_UARTS > 3
1531 [3] = {
1532 .port = {
1533 .lock = __PORT_LOCK_UNLOCKED(3),
1534 .iotype = UPIO_MEM,
1535 .uartclk = 0,
1536 .fifosize = 16,
1537 .ops = &s3c24xx_serial_ops,
1538 .flags = UPF_BOOT_AUTOCONF,
1539 .line = 3,
1540 }
1541 }
1542 #endif
1543 };
1544 #undef __PORT_LOCK_UNLOCKED
1545
1546 /* s3c24xx_serial_resetport
1547 *
1548 * reset the fifos and other the settings.
1549 */
1550
s3c24xx_serial_resetport(struct uart_port * port,struct s3c2410_uartcfg * cfg)1551 static void s3c24xx_serial_resetport(struct uart_port *port,
1552 struct s3c2410_uartcfg *cfg)
1553 {
1554 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1555 unsigned long ucon = rd_regl(port, S3C2410_UCON);
1556 unsigned int ucon_mask;
1557
1558 ucon_mask = info->clksel_mask;
1559 if (info->type == PORT_S3C2440)
1560 ucon_mask |= S3C2440_UCON0_DIVMASK;
1561
1562 ucon &= ucon_mask;
1563 wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);
1564
1565 /* reset both fifos */
1566 wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
1567 wr_regl(port, S3C2410_UFCON, cfg->ufcon);
1568
1569 /* some delay is required after fifo reset */
1570 udelay(1);
1571 }
1572
1573
1574 #ifdef CONFIG_CPU_FREQ
1575
s3c24xx_serial_cpufreq_transition(struct notifier_block * nb,unsigned long val,void * data)1576 static int s3c24xx_serial_cpufreq_transition(struct notifier_block *nb,
1577 unsigned long val, void *data)
1578 {
1579 struct s3c24xx_uart_port *port;
1580 struct uart_port *uport;
1581
1582 port = container_of(nb, struct s3c24xx_uart_port, freq_transition);
1583 uport = &port->port;
1584
1585 /* check to see if port is enabled */
1586
1587 if (port->pm_level != 0)
1588 return 0;
1589
1590 /* try and work out if the baudrate is changing, we can detect
1591 * a change in rate, but we do not have support for detecting
1592 * a disturbance in the clock-rate over the change.
1593 */
1594
1595 if (IS_ERR(port->baudclk))
1596 goto exit;
1597
1598 if (port->baudclk_rate == clk_get_rate(port->baudclk))
1599 goto exit;
1600
1601 if (val == CPUFREQ_PRECHANGE) {
1602 /* we should really shut the port down whilst the
1603 * frequency change is in progress. */
1604
1605 } else if (val == CPUFREQ_POSTCHANGE) {
1606 struct ktermios *termios;
1607 struct tty_struct *tty;
1608
1609 if (uport->state == NULL)
1610 goto exit;
1611
1612 tty = uport->state->port.tty;
1613
1614 if (tty == NULL)
1615 goto exit;
1616
1617 termios = &tty->termios;
1618
1619 if (termios == NULL) {
1620 dev_warn(uport->dev, "%s: no termios?\n", __func__);
1621 goto exit;
1622 }
1623
1624 s3c24xx_serial_set_termios(uport, termios, NULL);
1625 }
1626
1627 exit:
1628 return 0;
1629 }
1630
1631 static inline int
s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port * port)1632 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1633 {
1634 port->freq_transition.notifier_call = s3c24xx_serial_cpufreq_transition;
1635
1636 return cpufreq_register_notifier(&port->freq_transition,
1637 CPUFREQ_TRANSITION_NOTIFIER);
1638 }
1639
1640 static inline void
s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port * port)1641 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1642 {
1643 cpufreq_unregister_notifier(&port->freq_transition,
1644 CPUFREQ_TRANSITION_NOTIFIER);
1645 }
1646
1647 #else
1648 static inline int
s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port * port)1649 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1650 {
1651 return 0;
1652 }
1653
1654 static inline void
s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port * port)1655 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1656 {
1657 }
1658 #endif
1659
1660 /* s3c24xx_serial_init_port
1661 *
1662 * initialise a single serial port from the platform device given
1663 */
1664
s3c24xx_serial_init_port(struct s3c24xx_uart_port * ourport,struct platform_device * platdev)1665 static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
1666 struct platform_device *platdev)
1667 {
1668 struct uart_port *port = &ourport->port;
1669 struct s3c2410_uartcfg *cfg = ourport->cfg;
1670 struct resource *res;
1671 int ret;
1672
1673 dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev);
1674
1675 if (platdev == NULL)
1676 return -ENODEV;
1677
1678 if (port->mapbase != 0)
1679 return 0;
1680
1681 /* setup info for port */
1682 port->dev = &platdev->dev;
1683
1684 /* Startup sequence is different for s3c64xx and higher SoC's */
1685 if (s3c24xx_serial_has_interrupt_mask(port))
1686 s3c24xx_serial_ops.startup = s3c64xx_serial_startup;
1687
1688 port->uartclk = 1;
1689
1690 if (cfg->uart_flags & UPF_CONS_FLOW) {
1691 dbg("s3c24xx_serial_init_port: enabling flow control\n");
1692 port->flags |= UPF_CONS_FLOW;
1693 }
1694
1695 /* sort our the physical and virtual addresses for each UART */
1696
1697 res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
1698 if (res == NULL) {
1699 dev_err(port->dev, "failed to find memory resource for uart\n");
1700 return -EINVAL;
1701 }
1702
1703 dbg("resource %pR)\n", res);
1704
1705 port->membase = devm_ioremap(port->dev, res->start, resource_size(res));
1706 if (!port->membase) {
1707 dev_err(port->dev, "failed to remap controller address\n");
1708 return -EBUSY;
1709 }
1710
1711 port->mapbase = res->start;
1712 ret = platform_get_irq(platdev, 0);
1713 if (ret < 0)
1714 port->irq = 0;
1715 else {
1716 port->irq = ret;
1717 ourport->rx_irq = ret;
1718 ourport->tx_irq = ret + 1;
1719 }
1720
1721 ret = platform_get_irq(platdev, 1);
1722 if (ret > 0)
1723 ourport->tx_irq = ret;
1724 /*
1725 * DMA is currently supported only on DT platforms, if DMA properties
1726 * are specified.
1727 */
1728 if (platdev->dev.of_node && of_find_property(platdev->dev.of_node,
1729 "dmas", NULL)) {
1730 ourport->dma = devm_kzalloc(port->dev,
1731 sizeof(*ourport->dma),
1732 GFP_KERNEL);
1733 if (!ourport->dma)
1734 return -ENOMEM;
1735 }
1736
1737 ourport->clk = clk_get(&platdev->dev, "uart");
1738 if (IS_ERR(ourport->clk)) {
1739 pr_err("%s: Controller clock not found\n",
1740 dev_name(&platdev->dev));
1741 return PTR_ERR(ourport->clk);
1742 }
1743
1744 ret = clk_prepare_enable(ourport->clk);
1745 if (ret) {
1746 pr_err("uart: clock failed to prepare+enable: %d\n", ret);
1747 clk_put(ourport->clk);
1748 return ret;
1749 }
1750
1751 /* Keep all interrupts masked and cleared */
1752 if (s3c24xx_serial_has_interrupt_mask(port)) {
1753 wr_regl(port, S3C64XX_UINTM, 0xf);
1754 wr_regl(port, S3C64XX_UINTP, 0xf);
1755 wr_regl(port, S3C64XX_UINTSP, 0xf);
1756 }
1757
1758 dbg("port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n",
1759 &port->mapbase, port->membase, port->irq,
1760 ourport->rx_irq, ourport->tx_irq, port->uartclk);
1761
1762 /* reset the fifos (and setup the uart) */
1763 s3c24xx_serial_resetport(port, cfg);
1764 return 0;
1765 }
1766
1767 /* Device driver serial port probe */
1768
1769 static const struct of_device_id s3c24xx_uart_dt_match[];
1770 static int probe_index;
1771
s3c24xx_get_driver_data(struct platform_device * pdev)1772 static inline struct s3c24xx_serial_drv_data *s3c24xx_get_driver_data(
1773 struct platform_device *pdev)
1774 {
1775 #ifdef CONFIG_OF
1776 if (pdev->dev.of_node) {
1777 const struct of_device_id *match;
1778 match = of_match_node(s3c24xx_uart_dt_match, pdev->dev.of_node);
1779 return (struct s3c24xx_serial_drv_data *)match->data;
1780 }
1781 #endif
1782 return (struct s3c24xx_serial_drv_data *)
1783 platform_get_device_id(pdev)->driver_data;
1784 }
1785
s3c24xx_serial_probe(struct platform_device * pdev)1786 static int s3c24xx_serial_probe(struct platform_device *pdev)
1787 {
1788 struct device_node *np = pdev->dev.of_node;
1789 struct s3c24xx_uart_port *ourport;
1790 int index = probe_index;
1791 int ret;
1792
1793 if (np) {
1794 ret = of_alias_get_id(np, "serial");
1795 if (ret >= 0)
1796 index = ret;
1797 }
1798
1799 dbg("s3c24xx_serial_probe(%p) %d\n", pdev, index);
1800
1801 ourport = &s3c24xx_serial_ports[index];
1802
1803 ourport->drv_data = s3c24xx_get_driver_data(pdev);
1804 if (!ourport->drv_data) {
1805 dev_err(&pdev->dev, "could not find driver data\n");
1806 return -ENODEV;
1807 }
1808
1809 ourport->baudclk = ERR_PTR(-EINVAL);
1810 ourport->info = ourport->drv_data->info;
1811 ourport->cfg = (dev_get_platdata(&pdev->dev)) ?
1812 dev_get_platdata(&pdev->dev) :
1813 ourport->drv_data->def_cfg;
1814
1815 if (np)
1816 of_property_read_u32(np,
1817 "samsung,uart-fifosize", &ourport->port.fifosize);
1818
1819 if (ourport->drv_data->fifosize[index])
1820 ourport->port.fifosize = ourport->drv_data->fifosize[index];
1821 else if (ourport->info->fifosize)
1822 ourport->port.fifosize = ourport->info->fifosize;
1823
1824 /*
1825 * DMA transfers must be aligned at least to cache line size,
1826 * so find minimal transfer size suitable for DMA mode
1827 */
1828 ourport->min_dma_size = max_t(int, ourport->port.fifosize,
1829 dma_get_cache_alignment());
1830
1831 probe_index++;
1832
1833 dbg("%s: initialising port %p...\n", __func__, ourport);
1834
1835 ret = s3c24xx_serial_init_port(ourport, pdev);
1836 if (ret < 0)
1837 return ret;
1838
1839 if (!s3c24xx_uart_drv.state) {
1840 ret = uart_register_driver(&s3c24xx_uart_drv);
1841 if (ret < 0) {
1842 pr_err("Failed to register Samsung UART driver\n");
1843 return ret;
1844 }
1845 }
1846
1847 dbg("%s: adding port\n", __func__);
1848 uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
1849 platform_set_drvdata(pdev, &ourport->port);
1850
1851 /*
1852 * Deactivate the clock enabled in s3c24xx_serial_init_port here,
1853 * so that a potential re-enablement through the pm-callback overlaps
1854 * and keeps the clock enabled in this case.
1855 */
1856 clk_disable_unprepare(ourport->clk);
1857
1858 ret = s3c24xx_serial_cpufreq_register(ourport);
1859 if (ret < 0)
1860 dev_err(&pdev->dev, "failed to add cpufreq notifier\n");
1861
1862 return 0;
1863 }
1864
s3c24xx_serial_remove(struct platform_device * dev)1865 static int s3c24xx_serial_remove(struct platform_device *dev)
1866 {
1867 struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
1868
1869 if (port) {
1870 s3c24xx_serial_cpufreq_deregister(to_ourport(port));
1871 uart_remove_one_port(&s3c24xx_uart_drv, port);
1872 }
1873
1874 uart_unregister_driver(&s3c24xx_uart_drv);
1875
1876 return 0;
1877 }
1878
1879 /* UART power management code */
1880 #ifdef CONFIG_PM_SLEEP
s3c24xx_serial_suspend(struct device * dev)1881 static int s3c24xx_serial_suspend(struct device *dev)
1882 {
1883 struct uart_port *port = s3c24xx_dev_to_port(dev);
1884
1885 if (port)
1886 uart_suspend_port(&s3c24xx_uart_drv, port);
1887
1888 return 0;
1889 }
1890
s3c24xx_serial_resume(struct device * dev)1891 static int s3c24xx_serial_resume(struct device *dev)
1892 {
1893 struct uart_port *port = s3c24xx_dev_to_port(dev);
1894 struct s3c24xx_uart_port *ourport = to_ourport(port);
1895
1896 if (port) {
1897 clk_prepare_enable(ourport->clk);
1898 s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
1899 clk_disable_unprepare(ourport->clk);
1900
1901 uart_resume_port(&s3c24xx_uart_drv, port);
1902 }
1903
1904 return 0;
1905 }
1906
s3c24xx_serial_resume_noirq(struct device * dev)1907 static int s3c24xx_serial_resume_noirq(struct device *dev)
1908 {
1909 struct uart_port *port = s3c24xx_dev_to_port(dev);
1910
1911 if (port) {
1912 /* restore IRQ mask */
1913 if (s3c24xx_serial_has_interrupt_mask(port)) {
1914 unsigned int uintm = 0xf;
1915 if (tx_enabled(port))
1916 uintm &= ~S3C64XX_UINTM_TXD_MSK;
1917 if (rx_enabled(port))
1918 uintm &= ~S3C64XX_UINTM_RXD_MSK;
1919 wr_regl(port, S3C64XX_UINTM, uintm);
1920 }
1921 }
1922
1923 return 0;
1924 }
1925
1926 static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
1927 .suspend = s3c24xx_serial_suspend,
1928 .resume = s3c24xx_serial_resume,
1929 .resume_noirq = s3c24xx_serial_resume_noirq,
1930 };
1931 #define SERIAL_SAMSUNG_PM_OPS (&s3c24xx_serial_pm_ops)
1932
1933 #else /* !CONFIG_PM_SLEEP */
1934
1935 #define SERIAL_SAMSUNG_PM_OPS NULL
1936 #endif /* CONFIG_PM_SLEEP */
1937
1938 /* Console code */
1939
1940 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1941
1942 static struct uart_port *cons_uart;
1943
1944 static int
s3c24xx_serial_console_txrdy(struct uart_port * port,unsigned int ufcon)1945 s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
1946 {
1947 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1948 unsigned long ufstat, utrstat;
1949
1950 if (ufcon & S3C2410_UFCON_FIFOMODE) {
1951 /* fifo mode - check amount of data in fifo registers... */
1952
1953 ufstat = rd_regl(port, S3C2410_UFSTAT);
1954 return (ufstat & info->tx_fifofull) ? 0 : 1;
1955 }
1956
1957 /* in non-fifo mode, we go and use the tx buffer empty */
1958
1959 utrstat = rd_regl(port, S3C2410_UTRSTAT);
1960 return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
1961 }
1962
1963 static bool
s3c24xx_port_configured(unsigned int ucon)1964 s3c24xx_port_configured(unsigned int ucon)
1965 {
1966 /* consider the serial port configured if the tx/rx mode set */
1967 return (ucon & 0xf) != 0;
1968 }
1969
1970 #ifdef CONFIG_CONSOLE_POLL
1971 /*
1972 * Console polling routines for writing and reading from the uart while
1973 * in an interrupt or debug context.
1974 */
1975
s3c24xx_serial_get_poll_char(struct uart_port * port)1976 static int s3c24xx_serial_get_poll_char(struct uart_port *port)
1977 {
1978 struct s3c24xx_uart_port *ourport = to_ourport(port);
1979 unsigned int ufstat;
1980
1981 ufstat = rd_regl(port, S3C2410_UFSTAT);
1982 if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
1983 return NO_POLL_CHAR;
1984
1985 return rd_regb(port, S3C2410_URXH);
1986 }
1987
s3c24xx_serial_put_poll_char(struct uart_port * port,unsigned char c)1988 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1989 unsigned char c)
1990 {
1991 unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
1992 unsigned int ucon = rd_regl(port, S3C2410_UCON);
1993
1994 /* not possible to xmit on unconfigured port */
1995 if (!s3c24xx_port_configured(ucon))
1996 return;
1997
1998 while (!s3c24xx_serial_console_txrdy(port, ufcon))
1999 cpu_relax();
2000 wr_regb(port, S3C2410_UTXH, c);
2001 }
2002
2003 #endif /* CONFIG_CONSOLE_POLL */
2004
2005 static void
s3c24xx_serial_console_putchar(struct uart_port * port,int ch)2006 s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
2007 {
2008 unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2009
2010 while (!s3c24xx_serial_console_txrdy(port, ufcon))
2011 cpu_relax();
2012 wr_regb(port, S3C2410_UTXH, ch);
2013 }
2014
2015 static void
s3c24xx_serial_console_write(struct console * co,const char * s,unsigned int count)2016 s3c24xx_serial_console_write(struct console *co, const char *s,
2017 unsigned int count)
2018 {
2019 unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
2020
2021 /* not possible to xmit on unconfigured port */
2022 if (!s3c24xx_port_configured(ucon))
2023 return;
2024
2025 uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
2026 }
2027
2028 static void __init
s3c24xx_serial_get_options(struct uart_port * port,int * baud,int * parity,int * bits)2029 s3c24xx_serial_get_options(struct uart_port *port, int *baud,
2030 int *parity, int *bits)
2031 {
2032 struct clk *clk;
2033 unsigned int ulcon;
2034 unsigned int ucon;
2035 unsigned int ubrdiv;
2036 unsigned long rate;
2037 unsigned int clk_sel;
2038 char clk_name[MAX_CLK_NAME_LENGTH];
2039
2040 ulcon = rd_regl(port, S3C2410_ULCON);
2041 ucon = rd_regl(port, S3C2410_UCON);
2042 ubrdiv = rd_regl(port, S3C2410_UBRDIV);
2043
2044 dbg("s3c24xx_serial_get_options: port=%p\n"
2045 "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
2046 port, ulcon, ucon, ubrdiv);
2047
2048 if (s3c24xx_port_configured(ucon)) {
2049 switch (ulcon & S3C2410_LCON_CSMASK) {
2050 case S3C2410_LCON_CS5:
2051 *bits = 5;
2052 break;
2053 case S3C2410_LCON_CS6:
2054 *bits = 6;
2055 break;
2056 case S3C2410_LCON_CS7:
2057 *bits = 7;
2058 break;
2059 case S3C2410_LCON_CS8:
2060 default:
2061 *bits = 8;
2062 break;
2063 }
2064
2065 switch (ulcon & S3C2410_LCON_PMASK) {
2066 case S3C2410_LCON_PEVEN:
2067 *parity = 'e';
2068 break;
2069
2070 case S3C2410_LCON_PODD:
2071 *parity = 'o';
2072 break;
2073
2074 case S3C2410_LCON_PNONE:
2075 default:
2076 *parity = 'n';
2077 }
2078
2079 /* now calculate the baud rate */
2080
2081 clk_sel = s3c24xx_serial_getsource(port);
2082 sprintf(clk_name, "clk_uart_baud%d", clk_sel);
2083
2084 clk = clk_get(port->dev, clk_name);
2085 if (!IS_ERR(clk))
2086 rate = clk_get_rate(clk);
2087 else
2088 rate = 1;
2089
2090 *baud = rate / (16 * (ubrdiv + 1));
2091 dbg("calculated baud %d\n", *baud);
2092 }
2093
2094 }
2095
2096 static int __init
s3c24xx_serial_console_setup(struct console * co,char * options)2097 s3c24xx_serial_console_setup(struct console *co, char *options)
2098 {
2099 struct uart_port *port;
2100 int baud = 9600;
2101 int bits = 8;
2102 int parity = 'n';
2103 int flow = 'n';
2104
2105 dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
2106 co, co->index, options);
2107
2108 /* is this a valid port */
2109
2110 if (co->index == -1 || co->index >= CONFIG_SERIAL_SAMSUNG_UARTS)
2111 co->index = 0;
2112
2113 port = &s3c24xx_serial_ports[co->index].port;
2114
2115 /* is the port configured? */
2116
2117 if (port->mapbase == 0x0)
2118 return -ENODEV;
2119
2120 cons_uart = port;
2121
2122 dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
2123
2124 /*
2125 * Check whether an invalid uart number has been specified, and
2126 * if so, search for the first available port that does have
2127 * console support.
2128 */
2129 if (options)
2130 uart_parse_options(options, &baud, &parity, &bits, &flow);
2131 else
2132 s3c24xx_serial_get_options(port, &baud, &parity, &bits);
2133
2134 dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
2135
2136 return uart_set_options(port, co, baud, parity, bits, flow);
2137 }
2138
2139 static struct console s3c24xx_serial_console = {
2140 .name = S3C24XX_SERIAL_NAME,
2141 .device = uart_console_device,
2142 .flags = CON_PRINTBUFFER,
2143 .index = -1,
2144 .write = s3c24xx_serial_console_write,
2145 .setup = s3c24xx_serial_console_setup,
2146 .data = &s3c24xx_uart_drv,
2147 };
2148 #endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
2149
2150 #ifdef CONFIG_CPU_S3C2410
2151 static struct s3c24xx_serial_drv_data s3c2410_serial_drv_data = {
2152 .info = &(struct s3c24xx_uart_info) {
2153 .name = "Samsung S3C2410 UART",
2154 .type = PORT_S3C2410,
2155 .fifosize = 16,
2156 .rx_fifomask = S3C2410_UFSTAT_RXMASK,
2157 .rx_fifoshift = S3C2410_UFSTAT_RXSHIFT,
2158 .rx_fifofull = S3C2410_UFSTAT_RXFULL,
2159 .tx_fifofull = S3C2410_UFSTAT_TXFULL,
2160 .tx_fifomask = S3C2410_UFSTAT_TXMASK,
2161 .tx_fifoshift = S3C2410_UFSTAT_TXSHIFT,
2162 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2163 .num_clks = 2,
2164 .clksel_mask = S3C2410_UCON_CLKMASK,
2165 .clksel_shift = S3C2410_UCON_CLKSHIFT,
2166 },
2167 .def_cfg = &(struct s3c2410_uartcfg) {
2168 .ucon = S3C2410_UCON_DEFAULT,
2169 .ufcon = S3C2410_UFCON_DEFAULT,
2170 },
2171 };
2172 #define S3C2410_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2410_serial_drv_data)
2173 #else
2174 #define S3C2410_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2175 #endif
2176
2177 #ifdef CONFIG_CPU_S3C2412
2178 static struct s3c24xx_serial_drv_data s3c2412_serial_drv_data = {
2179 .info = &(struct s3c24xx_uart_info) {
2180 .name = "Samsung S3C2412 UART",
2181 .type = PORT_S3C2412,
2182 .fifosize = 64,
2183 .has_divslot = 1,
2184 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
2185 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
2186 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
2187 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
2188 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
2189 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
2190 .def_clk_sel = S3C2410_UCON_CLKSEL2,
2191 .num_clks = 4,
2192 .clksel_mask = S3C2412_UCON_CLKMASK,
2193 .clksel_shift = S3C2412_UCON_CLKSHIFT,
2194 },
2195 .def_cfg = &(struct s3c2410_uartcfg) {
2196 .ucon = S3C2410_UCON_DEFAULT,
2197 .ufcon = S3C2410_UFCON_DEFAULT,
2198 },
2199 };
2200 #define S3C2412_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2412_serial_drv_data)
2201 #else
2202 #define S3C2412_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2203 #endif
2204
2205 #if defined(CONFIG_CPU_S3C2440) || defined(CONFIG_CPU_S3C2416) || \
2206 defined(CONFIG_CPU_S3C2443) || defined(CONFIG_CPU_S3C2442)
2207 static struct s3c24xx_serial_drv_data s3c2440_serial_drv_data = {
2208 .info = &(struct s3c24xx_uart_info) {
2209 .name = "Samsung S3C2440 UART",
2210 .type = PORT_S3C2440,
2211 .fifosize = 64,
2212 .has_divslot = 1,
2213 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
2214 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
2215 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
2216 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
2217 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
2218 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
2219 .def_clk_sel = S3C2410_UCON_CLKSEL2,
2220 .num_clks = 4,
2221 .clksel_mask = S3C2412_UCON_CLKMASK,
2222 .clksel_shift = S3C2412_UCON_CLKSHIFT,
2223 },
2224 .def_cfg = &(struct s3c2410_uartcfg) {
2225 .ucon = S3C2410_UCON_DEFAULT,
2226 .ufcon = S3C2410_UFCON_DEFAULT,
2227 },
2228 };
2229 #define S3C2440_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2440_serial_drv_data)
2230 #else
2231 #define S3C2440_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2232 #endif
2233
2234 #if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)
2235 static struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {
2236 .info = &(struct s3c24xx_uart_info) {
2237 .name = "Samsung S3C6400 UART",
2238 .type = PORT_S3C6400,
2239 .fifosize = 64,
2240 .has_divslot = 1,
2241 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
2242 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
2243 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
2244 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
2245 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
2246 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
2247 .def_clk_sel = S3C2410_UCON_CLKSEL2,
2248 .num_clks = 4,
2249 .clksel_mask = S3C6400_UCON_CLKMASK,
2250 .clksel_shift = S3C6400_UCON_CLKSHIFT,
2251 },
2252 .def_cfg = &(struct s3c2410_uartcfg) {
2253 .ucon = S3C2410_UCON_DEFAULT,
2254 .ufcon = S3C2410_UFCON_DEFAULT,
2255 },
2256 };
2257 #define S3C6400_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c6400_serial_drv_data)
2258 #else
2259 #define S3C6400_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2260 #endif
2261
2262 #ifdef CONFIG_CPU_S5PV210
2263 static struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {
2264 .info = &(struct s3c24xx_uart_info) {
2265 .name = "Samsung S5PV210 UART",
2266 .type = PORT_S3C6400,
2267 .has_divslot = 1,
2268 .rx_fifomask = S5PV210_UFSTAT_RXMASK,
2269 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT,
2270 .rx_fifofull = S5PV210_UFSTAT_RXFULL,
2271 .tx_fifofull = S5PV210_UFSTAT_TXFULL,
2272 .tx_fifomask = S5PV210_UFSTAT_TXMASK,
2273 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT,
2274 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2275 .num_clks = 2,
2276 .clksel_mask = S5PV210_UCON_CLKMASK,
2277 .clksel_shift = S5PV210_UCON_CLKSHIFT,
2278 },
2279 .def_cfg = &(struct s3c2410_uartcfg) {
2280 .ucon = S5PV210_UCON_DEFAULT,
2281 .ufcon = S5PV210_UFCON_DEFAULT,
2282 },
2283 .fifosize = { 256, 64, 16, 16 },
2284 };
2285 #define S5PV210_SERIAL_DRV_DATA ((kernel_ulong_t)&s5pv210_serial_drv_data)
2286 #else
2287 #define S5PV210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2288 #endif
2289
2290 #if defined(CONFIG_ARCH_EXYNOS)
2291 #define EXYNOS_COMMON_SERIAL_DRV_DATA \
2292 .info = &(struct s3c24xx_uart_info) { \
2293 .name = "Samsung Exynos UART", \
2294 .type = PORT_S3C6400, \
2295 .has_divslot = 1, \
2296 .rx_fifomask = S5PV210_UFSTAT_RXMASK, \
2297 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT, \
2298 .rx_fifofull = S5PV210_UFSTAT_RXFULL, \
2299 .tx_fifofull = S5PV210_UFSTAT_TXFULL, \
2300 .tx_fifomask = S5PV210_UFSTAT_TXMASK, \
2301 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT, \
2302 .def_clk_sel = S3C2410_UCON_CLKSEL0, \
2303 .num_clks = 1, \
2304 .clksel_mask = 0, \
2305 .clksel_shift = 0, \
2306 }, \
2307 .def_cfg = &(struct s3c2410_uartcfg) { \
2308 .ucon = S5PV210_UCON_DEFAULT, \
2309 .ufcon = S5PV210_UFCON_DEFAULT, \
2310 .has_fracval = 1, \
2311 } \
2312
2313 static struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {
2314 EXYNOS_COMMON_SERIAL_DRV_DATA,
2315 .fifosize = { 256, 64, 16, 16 },
2316 };
2317
2318 static struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {
2319 EXYNOS_COMMON_SERIAL_DRV_DATA,
2320 .fifosize = { 64, 256, 16, 256 },
2321 };
2322
2323 #define EXYNOS4210_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos4210_serial_drv_data)
2324 #define EXYNOS5433_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos5433_serial_drv_data)
2325 #else
2326 #define EXYNOS4210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2327 #define EXYNOS5433_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2328 #endif
2329
2330 static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
2331 {
2332 .name = "s3c2410-uart",
2333 .driver_data = S3C2410_SERIAL_DRV_DATA,
2334 }, {
2335 .name = "s3c2412-uart",
2336 .driver_data = S3C2412_SERIAL_DRV_DATA,
2337 }, {
2338 .name = "s3c2440-uart",
2339 .driver_data = S3C2440_SERIAL_DRV_DATA,
2340 }, {
2341 .name = "s3c6400-uart",
2342 .driver_data = S3C6400_SERIAL_DRV_DATA,
2343 }, {
2344 .name = "s5pv210-uart",
2345 .driver_data = S5PV210_SERIAL_DRV_DATA,
2346 }, {
2347 .name = "exynos4210-uart",
2348 .driver_data = EXYNOS4210_SERIAL_DRV_DATA,
2349 }, {
2350 .name = "exynos5433-uart",
2351 .driver_data = EXYNOS5433_SERIAL_DRV_DATA,
2352 },
2353 { },
2354 };
2355 MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);
2356
2357 #ifdef CONFIG_OF
2358 static const struct of_device_id s3c24xx_uart_dt_match[] = {
2359 { .compatible = "samsung,s3c2410-uart",
2360 .data = (void *)S3C2410_SERIAL_DRV_DATA },
2361 { .compatible = "samsung,s3c2412-uart",
2362 .data = (void *)S3C2412_SERIAL_DRV_DATA },
2363 { .compatible = "samsung,s3c2440-uart",
2364 .data = (void *)S3C2440_SERIAL_DRV_DATA },
2365 { .compatible = "samsung,s3c6400-uart",
2366 .data = (void *)S3C6400_SERIAL_DRV_DATA },
2367 { .compatible = "samsung,s5pv210-uart",
2368 .data = (void *)S5PV210_SERIAL_DRV_DATA },
2369 { .compatible = "samsung,exynos4210-uart",
2370 .data = (void *)EXYNOS4210_SERIAL_DRV_DATA },
2371 { .compatible = "samsung,exynos5433-uart",
2372 .data = (void *)EXYNOS5433_SERIAL_DRV_DATA },
2373 {},
2374 };
2375 MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
2376 #endif
2377
2378 static struct platform_driver samsung_serial_driver = {
2379 .probe = s3c24xx_serial_probe,
2380 .remove = s3c24xx_serial_remove,
2381 .id_table = s3c24xx_serial_driver_ids,
2382 .driver = {
2383 .name = "samsung-uart",
2384 .pm = SERIAL_SAMSUNG_PM_OPS,
2385 .of_match_table = of_match_ptr(s3c24xx_uart_dt_match),
2386 },
2387 };
2388
2389 module_platform_driver(samsung_serial_driver);
2390
2391 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
2392 /*
2393 * Early console.
2394 */
2395
2396 struct samsung_early_console_data {
2397 u32 txfull_mask;
2398 };
2399
samsung_early_busyuart(struct uart_port * port)2400 static void samsung_early_busyuart(struct uart_port *port)
2401 {
2402 while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))
2403 ;
2404 }
2405
samsung_early_busyuart_fifo(struct uart_port * port)2406 static void samsung_early_busyuart_fifo(struct uart_port *port)
2407 {
2408 struct samsung_early_console_data *data = port->private_data;
2409
2410 while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)
2411 ;
2412 }
2413
samsung_early_putc(struct uart_port * port,int c)2414 static void samsung_early_putc(struct uart_port *port, int c)
2415 {
2416 if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
2417 samsung_early_busyuart_fifo(port);
2418 else
2419 samsung_early_busyuart(port);
2420
2421 writeb(c, port->membase + S3C2410_UTXH);
2422 }
2423
samsung_early_write(struct console * con,const char * s,unsigned n)2424 static void samsung_early_write(struct console *con, const char *s, unsigned n)
2425 {
2426 struct earlycon_device *dev = con->data;
2427
2428 uart_console_write(&dev->port, s, n, samsung_early_putc);
2429 }
2430
samsung_early_console_setup(struct earlycon_device * device,const char * opt)2431 static int __init samsung_early_console_setup(struct earlycon_device *device,
2432 const char *opt)
2433 {
2434 if (!device->port.membase)
2435 return -ENODEV;
2436
2437 device->con->write = samsung_early_write;
2438 return 0;
2439 }
2440
2441 /* S3C2410 */
2442 static struct samsung_early_console_data s3c2410_early_console_data = {
2443 .txfull_mask = S3C2410_UFSTAT_TXFULL,
2444 };
2445
s3c2410_early_console_setup(struct earlycon_device * device,const char * opt)2446 static int __init s3c2410_early_console_setup(struct earlycon_device *device,
2447 const char *opt)
2448 {
2449 device->port.private_data = &s3c2410_early_console_data;
2450 return samsung_early_console_setup(device, opt);
2451 }
2452 OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart",
2453 s3c2410_early_console_setup);
2454 EARLYCON_DECLARE(s3c2410, s3c2410_early_console_setup);
2455
2456 /* S3C2412, S3C2440, S3C64xx */
2457 static struct samsung_early_console_data s3c2440_early_console_data = {
2458 .txfull_mask = S3C2440_UFSTAT_TXFULL,
2459 };
2460
s3c2440_early_console_setup(struct earlycon_device * device,const char * opt)2461 static int __init s3c2440_early_console_setup(struct earlycon_device *device,
2462 const char *opt)
2463 {
2464 device->port.private_data = &s3c2440_early_console_data;
2465 return samsung_early_console_setup(device, opt);
2466 }
2467 OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart",
2468 s3c2440_early_console_setup);
2469 OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart",
2470 s3c2440_early_console_setup);
2471 OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",
2472 s3c2440_early_console_setup);
2473 EARLYCON_DECLARE(s3c2412, s3c2440_early_console_setup);
2474 EARLYCON_DECLARE(s3c2440, s3c2440_early_console_setup);
2475 EARLYCON_DECLARE(s3c6400, s3c2440_early_console_setup);
2476
2477 /* S5PV210, EXYNOS */
2478 static struct samsung_early_console_data s5pv210_early_console_data = {
2479 .txfull_mask = S5PV210_UFSTAT_TXFULL,
2480 };
2481
s5pv210_early_console_setup(struct earlycon_device * device,const char * opt)2482 static int __init s5pv210_early_console_setup(struct earlycon_device *device,
2483 const char *opt)
2484 {
2485 device->port.private_data = &s5pv210_early_console_data;
2486 return samsung_early_console_setup(device, opt);
2487 }
2488 OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
2489 s5pv210_early_console_setup);
2490 OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
2491 s5pv210_early_console_setup);
2492 EARLYCON_DECLARE(s5pv210, s5pv210_early_console_setup);
2493 EARLYCON_DECLARE(exynos4210, s5pv210_early_console_setup);
2494 #endif
2495
2496 MODULE_ALIAS("platform:samsung-uart");
2497 MODULE_DESCRIPTION("Samsung SoC Serial port driver");
2498 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
2499 MODULE_LICENSE("GPL v2");
2500