1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver core for Samsung SoC onboard UARTs.
4 *
5 * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
6 * http://armlinux.simtec.co.uk/
7 */
8
9 /* Note on 2410 error handling
10 *
11 * The s3c2410 manual has a love/hate affair with the contents of the
12 * UERSTAT register in the UART blocks, and keeps marking some of the
13 * error bits as reserved. Having checked with the s3c2410x01,
14 * it copes with BREAKs properly, so I am happy to ignore the RESERVED
15 * feature from the latter versions of the manual.
16 *
17 * If it becomes aparrent that latter versions of the 2410 remove these
18 * bits, then action will have to be taken to differentiate the versions
19 * and change the policy on BREAK
20 *
21 * BJD, 04-Nov-2004
22 */
23
24 #include <linux/console.h>
25 #include <linux/clk.h>
26 #include <linux/cpufreq.h>
27 #include <linux/delay.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/dmaengine.h>
30 #include <linux/init.h>
31 #include <linux/io.h>
32 #include <linux/ioport.h>
33 #include <linux/math.h>
34 #include <linux/module.h>
35 #include <linux/of.h>
36 #include <linux/platform_device.h>
37 #include <linux/serial.h>
38 #include <linux/serial_core.h>
39 #include <linux/serial_s3c.h>
40 #include <linux/slab.h>
41 #include <linux/sysrq.h>
42 #include <linux/tty.h>
43 #include <linux/tty_flip.h>
44 #include <linux/types.h>
45
46 #include <asm/irq.h>
47
48 /* UART name and device definitions */
49
50 #define S3C24XX_SERIAL_NAME "ttySAC"
51 #define S3C24XX_SERIAL_MAJOR 204
52 #define S3C24XX_SERIAL_MINOR 64
53
54 #ifdef CONFIG_ARM64
55 #define UART_NR 12
56 #else
57 #define UART_NR CONFIG_SERIAL_SAMSUNG_UARTS
58 #endif
59
60 #define S3C24XX_TX_PIO 1
61 #define S3C24XX_TX_DMA 2
62 #define S3C24XX_RX_PIO 1
63 #define S3C24XX_RX_DMA 2
64
65 /* flag to ignore all characters coming in */
66 #define RXSTAT_DUMMY_READ (0x10000000)
67
68 enum s3c24xx_port_type {
69 TYPE_S3C6400,
70 TYPE_APPLE_S5L,
71 };
72
73 struct s3c24xx_uart_info {
74 const char *name;
75 enum s3c24xx_port_type type;
76 unsigned int port_type;
77 unsigned int fifosize;
78 u32 rx_fifomask;
79 u32 rx_fifoshift;
80 u32 rx_fifofull;
81 u32 tx_fifomask;
82 u32 tx_fifoshift;
83 u32 tx_fifofull;
84 u32 clksel_mask;
85 u32 clksel_shift;
86 u32 ucon_mask;
87 u8 def_clk_sel;
88 u8 num_clks;
89 u8 iotype;
90
91 /* uart port features */
92 bool has_divslot;
93 };
94
95 struct s3c24xx_serial_drv_data {
96 const struct s3c24xx_uart_info info;
97 const struct s3c2410_uartcfg def_cfg;
98 const unsigned int fifosize[UART_NR];
99 };
100
101 struct s3c24xx_uart_dma {
102 unsigned int rx_chan_id;
103 unsigned int tx_chan_id;
104
105 struct dma_slave_config rx_conf;
106 struct dma_slave_config tx_conf;
107
108 struct dma_chan *rx_chan;
109 struct dma_chan *tx_chan;
110
111 dma_addr_t rx_addr;
112 dma_addr_t tx_addr;
113
114 dma_cookie_t rx_cookie;
115 dma_cookie_t tx_cookie;
116
117 char *rx_buf;
118
119 dma_addr_t tx_transfer_addr;
120
121 size_t rx_size;
122 size_t tx_size;
123
124 struct dma_async_tx_descriptor *tx_desc;
125 struct dma_async_tx_descriptor *rx_desc;
126
127 int tx_bytes_requested;
128 int rx_bytes_requested;
129 };
130
131 struct s3c24xx_uart_port {
132 unsigned char rx_enabled;
133 unsigned char tx_enabled;
134 unsigned int pm_level;
135 unsigned long baudclk_rate;
136 unsigned int min_dma_size;
137
138 unsigned int rx_irq;
139 unsigned int tx_irq;
140
141 unsigned int tx_in_progress;
142 unsigned int tx_mode;
143 unsigned int rx_mode;
144
145 const struct s3c24xx_uart_info *info;
146 struct clk *clk;
147 struct clk *baudclk;
148 struct uart_port port;
149 const struct s3c24xx_serial_drv_data *drv_data;
150
151 /* reference to platform data */
152 const struct s3c2410_uartcfg *cfg;
153
154 struct s3c24xx_uart_dma *dma;
155 };
156
157 static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport);
158
159 /* conversion functions */
160
161 #define s3c24xx_dev_to_port(__dev) dev_get_drvdata(__dev)
162
163 /* register access controls */
164
165 #define portaddr(port, reg) ((port)->membase + (reg))
166 #define portaddrl(port, reg) \
167 ((unsigned long *)(unsigned long)((port)->membase + (reg)))
168
rd_reg(const struct uart_port * port,u32 reg)169 static u32 rd_reg(const struct uart_port *port, u32 reg)
170 {
171 switch (port->iotype) {
172 case UPIO_MEM:
173 return readb_relaxed(portaddr(port, reg));
174 case UPIO_MEM32:
175 return readl_relaxed(portaddr(port, reg));
176 default:
177 return 0;
178 }
179 return 0;
180 }
181
182 #define rd_regl(port, reg) (readl_relaxed(portaddr(port, reg)))
183
wr_reg(const struct uart_port * port,u32 reg,u32 val)184 static void wr_reg(const struct uart_port *port, u32 reg, u32 val)
185 {
186 switch (port->iotype) {
187 case UPIO_MEM:
188 writeb_relaxed(val, portaddr(port, reg));
189 break;
190 case UPIO_MEM32:
191 writel_relaxed(val, portaddr(port, reg));
192 break;
193 }
194 }
195
196 #define wr_regl(port, reg, val) writel_relaxed(val, portaddr(port, reg))
197
198 /* Byte-order aware bit setting/clearing functions. */
199
s3c24xx_set_bit(const struct uart_port * port,int idx,u32 reg)200 static inline void s3c24xx_set_bit(const struct uart_port *port, int idx,
201 u32 reg)
202 {
203 unsigned long flags;
204 u32 val;
205
206 local_irq_save(flags);
207 val = rd_regl(port, reg);
208 val |= (1 << idx);
209 wr_regl(port, reg, val);
210 local_irq_restore(flags);
211 }
212
s3c24xx_clear_bit(const struct uart_port * port,int idx,u32 reg)213 static inline void s3c24xx_clear_bit(const struct uart_port *port, int idx,
214 u32 reg)
215 {
216 unsigned long flags;
217 u32 val;
218
219 local_irq_save(flags);
220 val = rd_regl(port, reg);
221 val &= ~(1 << idx);
222 wr_regl(port, reg, val);
223 local_irq_restore(flags);
224 }
225
to_ourport(struct uart_port * port)226 static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
227 {
228 return container_of(port, struct s3c24xx_uart_port, port);
229 }
230
231 /* translate a port to the device name */
232
s3c24xx_serial_portname(const struct uart_port * port)233 static inline const char *s3c24xx_serial_portname(const struct uart_port *port)
234 {
235 return to_platform_device(port->dev)->name;
236 }
237
s3c24xx_serial_txempty_nofifo(const struct uart_port * port)238 static bool s3c24xx_serial_txempty_nofifo(const struct uart_port *port)
239 {
240 return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;
241 }
242
s3c24xx_serial_rx_enable(struct uart_port * port)243 static void s3c24xx_serial_rx_enable(struct uart_port *port)
244 {
245 struct s3c24xx_uart_port *ourport = to_ourport(port);
246 unsigned long flags;
247 int count = 10000;
248 u32 ucon, ufcon;
249
250 uart_port_lock_irqsave(port, &flags);
251
252 while (--count && !s3c24xx_serial_txempty_nofifo(port))
253 udelay(100);
254
255 ufcon = rd_regl(port, S3C2410_UFCON);
256 ufcon |= S3C2410_UFCON_RESETRX;
257 wr_regl(port, S3C2410_UFCON, ufcon);
258
259 ucon = rd_regl(port, S3C2410_UCON);
260 ucon |= S3C2410_UCON_RXIRQMODE;
261 wr_regl(port, S3C2410_UCON, ucon);
262
263 ourport->rx_enabled = 1;
264 uart_port_unlock_irqrestore(port, flags);
265 }
266
s3c24xx_serial_rx_disable(struct uart_port * port)267 static void s3c24xx_serial_rx_disable(struct uart_port *port)
268 {
269 struct s3c24xx_uart_port *ourport = to_ourport(port);
270 unsigned long flags;
271 u32 ucon;
272
273 uart_port_lock_irqsave(port, &flags);
274
275 ucon = rd_regl(port, S3C2410_UCON);
276 ucon &= ~S3C2410_UCON_RXIRQMODE;
277 wr_regl(port, S3C2410_UCON, ucon);
278
279 ourport->rx_enabled = 0;
280 uart_port_unlock_irqrestore(port, flags);
281 }
282
s3c24xx_serial_stop_tx(struct uart_port * port)283 static void s3c24xx_serial_stop_tx(struct uart_port *port)
284 {
285 struct s3c24xx_uart_port *ourport = to_ourport(port);
286 struct s3c24xx_uart_dma *dma = ourport->dma;
287 struct dma_tx_state state;
288 int count;
289
290 if (!ourport->tx_enabled)
291 return;
292
293 switch (ourport->info->type) {
294 case TYPE_S3C6400:
295 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
296 break;
297 case TYPE_APPLE_S5L:
298 s3c24xx_clear_bit(port, APPLE_S5L_UCON_TXTHRESH_ENA, S3C2410_UCON);
299 break;
300 default:
301 disable_irq_nosync(ourport->tx_irq);
302 break;
303 }
304
305 if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {
306 dmaengine_pause(dma->tx_chan);
307 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
308 dmaengine_terminate_all(dma->tx_chan);
309 dma_sync_single_for_cpu(dma->tx_chan->device->dev,
310 dma->tx_transfer_addr, dma->tx_size,
311 DMA_TO_DEVICE);
312 async_tx_ack(dma->tx_desc);
313 count = dma->tx_bytes_requested - state.residue;
314 uart_xmit_advance(port, count);
315 }
316
317 ourport->tx_enabled = 0;
318 ourport->tx_in_progress = 0;
319
320 if (port->flags & UPF_CONS_FLOW)
321 s3c24xx_serial_rx_enable(port);
322
323 ourport->tx_mode = 0;
324 }
325
326 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
327
s3c24xx_serial_tx_dma_complete(void * args)328 static void s3c24xx_serial_tx_dma_complete(void *args)
329 {
330 struct s3c24xx_uart_port *ourport = args;
331 struct uart_port *port = &ourport->port;
332 struct tty_port *tport = &port->state->port;
333 struct s3c24xx_uart_dma *dma = ourport->dma;
334 struct dma_tx_state state;
335 unsigned long flags;
336 int count;
337
338 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
339 count = dma->tx_bytes_requested - state.residue;
340 async_tx_ack(dma->tx_desc);
341
342 dma_sync_single_for_cpu(dma->tx_chan->device->dev,
343 dma->tx_transfer_addr, dma->tx_size,
344 DMA_TO_DEVICE);
345
346 uart_port_lock_irqsave(port, &flags);
347
348 uart_xmit_advance(port, count);
349 ourport->tx_in_progress = 0;
350
351 if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
352 uart_write_wakeup(port);
353
354 s3c24xx_serial_start_next_tx(ourport);
355 uart_port_unlock_irqrestore(port, flags);
356 }
357
enable_tx_dma(struct s3c24xx_uart_port * ourport)358 static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
359 {
360 const struct uart_port *port = &ourport->port;
361 u32 ucon;
362
363 /* Mask Tx interrupt */
364 switch (ourport->info->type) {
365 case TYPE_S3C6400:
366 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
367 break;
368 case TYPE_APPLE_S5L:
369 WARN_ON(1); // No DMA
370 break;
371 default:
372 disable_irq_nosync(ourport->tx_irq);
373 break;
374 }
375
376 /* Enable tx dma mode */
377 ucon = rd_regl(port, S3C2410_UCON);
378 ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
379 ucon |= S3C64XX_UCON_TXBURST_1;
380 ucon |= S3C64XX_UCON_TXMODE_DMA;
381 wr_regl(port, S3C2410_UCON, ucon);
382
383 ourport->tx_mode = S3C24XX_TX_DMA;
384 }
385
enable_tx_pio(struct s3c24xx_uart_port * ourport)386 static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
387 {
388 const struct uart_port *port = &ourport->port;
389 u32 ucon, ufcon;
390
391 /* Set ufcon txtrig */
392 ourport->tx_in_progress = S3C24XX_TX_PIO;
393 ufcon = rd_regl(port, S3C2410_UFCON);
394 wr_regl(port, S3C2410_UFCON, ufcon);
395
396 /* Enable tx pio mode */
397 ucon = rd_regl(port, S3C2410_UCON);
398 ucon &= ~(S3C64XX_UCON_TXMODE_MASK);
399 ucon |= S3C64XX_UCON_TXMODE_CPU;
400 wr_regl(port, S3C2410_UCON, ucon);
401
402 /* Unmask Tx interrupt */
403 switch (ourport->info->type) {
404 case TYPE_S3C6400:
405 s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,
406 S3C64XX_UINTM);
407 break;
408 case TYPE_APPLE_S5L:
409 ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK;
410 wr_regl(port, S3C2410_UCON, ucon);
411 break;
412 default:
413 enable_irq(ourport->tx_irq);
414 break;
415 }
416
417 ourport->tx_mode = S3C24XX_TX_PIO;
418
419 /*
420 * The Apple version only has edge triggered TX IRQs, so we need
421 * to kick off the process by sending some characters here.
422 */
423 if (ourport->info->type == TYPE_APPLE_S5L)
424 s3c24xx_serial_tx_chars(ourport);
425 }
426
s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port * ourport)427 static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)
428 {
429 if (ourport->tx_mode != S3C24XX_TX_PIO)
430 enable_tx_pio(ourport);
431 }
432
s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port * ourport,unsigned int count,unsigned int tail)433 static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
434 unsigned int count, unsigned int tail)
435 {
436 struct s3c24xx_uart_dma *dma = ourport->dma;
437
438 if (ourport->tx_mode != S3C24XX_TX_DMA)
439 enable_tx_dma(ourport);
440
441 dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
442 dma->tx_transfer_addr = dma->tx_addr + tail;
443
444 dma_sync_single_for_device(dma->tx_chan->device->dev,
445 dma->tx_transfer_addr, dma->tx_size,
446 DMA_TO_DEVICE);
447
448 dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,
449 dma->tx_transfer_addr, dma->tx_size,
450 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
451 if (!dma->tx_desc) {
452 dev_err(ourport->port.dev, "Unable to get desc for Tx\n");
453 return -EIO;
454 }
455
456 dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;
457 dma->tx_desc->callback_param = ourport;
458 dma->tx_bytes_requested = dma->tx_size;
459
460 ourport->tx_in_progress = S3C24XX_TX_DMA;
461 dma->tx_cookie = dmaengine_submit(dma->tx_desc);
462 dma_async_issue_pending(dma->tx_chan);
463 return 0;
464 }
465
s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port * ourport)466 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
467 {
468 struct uart_port *port = &ourport->port;
469 struct tty_port *tport = &port->state->port;
470 unsigned int count, tail;
471
472 /* Get data size up to the end of buffer */
473 count = kfifo_out_linear(&tport->xmit_fifo, &tail, UART_XMIT_SIZE);
474
475 if (!count) {
476 s3c24xx_serial_stop_tx(port);
477 return;
478 }
479
480 if (!ourport->dma || !ourport->dma->tx_chan ||
481 count < ourport->min_dma_size ||
482 tail & (dma_get_cache_alignment() - 1))
483 s3c24xx_serial_start_tx_pio(ourport);
484 else
485 s3c24xx_serial_start_tx_dma(ourport, count, tail);
486 }
487
s3c24xx_serial_start_tx(struct uart_port * port)488 static void s3c24xx_serial_start_tx(struct uart_port *port)
489 {
490 struct s3c24xx_uart_port *ourport = to_ourport(port);
491 struct tty_port *tport = &port->state->port;
492
493 if (!ourport->tx_enabled) {
494 if (port->flags & UPF_CONS_FLOW)
495 s3c24xx_serial_rx_disable(port);
496
497 ourport->tx_enabled = 1;
498 if (!ourport->dma || !ourport->dma->tx_chan)
499 s3c24xx_serial_start_tx_pio(ourport);
500 }
501
502 if (ourport->dma && ourport->dma->tx_chan) {
503 if (!kfifo_is_empty(&tport->xmit_fifo) &&
504 !ourport->tx_in_progress)
505 s3c24xx_serial_start_next_tx(ourport);
506 }
507 }
508
s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port * ourport,struct tty_port * tty,int count)509 static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,
510 struct tty_port *tty, int count)
511 {
512 struct s3c24xx_uart_dma *dma = ourport->dma;
513 int copied;
514
515 if (!count)
516 return;
517
518 dma_sync_single_for_cpu(dma->rx_chan->device->dev, dma->rx_addr,
519 dma->rx_size, DMA_FROM_DEVICE);
520
521 ourport->port.icount.rx += count;
522 if (!tty) {
523 dev_err(ourport->port.dev, "No tty port\n");
524 return;
525 }
526 copied = tty_insert_flip_string(tty,
527 ((unsigned char *)(ourport->dma->rx_buf)), count);
528 if (copied != count) {
529 WARN_ON(1);
530 dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");
531 }
532 }
533
s3c24xx_serial_stop_rx(struct uart_port * port)534 static void s3c24xx_serial_stop_rx(struct uart_port *port)
535 {
536 struct s3c24xx_uart_port *ourport = to_ourport(port);
537 struct s3c24xx_uart_dma *dma = ourport->dma;
538 struct tty_port *t = &port->state->port;
539 struct dma_tx_state state;
540 enum dma_status dma_status;
541 unsigned int received;
542
543 if (ourport->rx_enabled) {
544 dev_dbg(port->dev, "stopping rx\n");
545 switch (ourport->info->type) {
546 case TYPE_S3C6400:
547 s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,
548 S3C64XX_UINTM);
549 break;
550 case TYPE_APPLE_S5L:
551 s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON);
552 s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON);
553 s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTO_LEGACY_ENA, S3C2410_UCON);
554 break;
555 default:
556 disable_irq_nosync(ourport->rx_irq);
557 break;
558 }
559 ourport->rx_enabled = 0;
560 }
561 if (dma && dma->rx_chan) {
562 dmaengine_pause(dma->tx_chan);
563 dma_status = dmaengine_tx_status(dma->rx_chan,
564 dma->rx_cookie, &state);
565 if (dma_status == DMA_IN_PROGRESS ||
566 dma_status == DMA_PAUSED) {
567 received = dma->rx_bytes_requested - state.residue;
568 dmaengine_terminate_all(dma->rx_chan);
569 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
570 }
571 }
572 }
573
574 static inline const struct s3c24xx_uart_info
s3c24xx_port_to_info(struct uart_port * port)575 *s3c24xx_port_to_info(struct uart_port *port)
576 {
577 return to_ourport(port)->info;
578 }
579
580 static inline const struct s3c2410_uartcfg
s3c24xx_port_to_cfg(const struct uart_port * port)581 *s3c24xx_port_to_cfg(const struct uart_port *port)
582 {
583 const struct s3c24xx_uart_port *ourport;
584
585 if (port->dev == NULL)
586 return NULL;
587
588 ourport = container_of(port, struct s3c24xx_uart_port, port);
589 return ourport->cfg;
590 }
591
592 static unsigned int
s3c24xx_serial_rx_fifocnt(const struct s3c24xx_uart_port * ourport,u32 ufstat)593 s3c24xx_serial_rx_fifocnt(const struct s3c24xx_uart_port *ourport, u32 ufstat)
594 {
595 const struct s3c24xx_uart_info *info = ourport->info;
596
597 if (ufstat & info->rx_fifofull)
598 return ourport->port.fifosize;
599
600 return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
601 }
602
603 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
s3c24xx_serial_rx_dma_complete(void * args)604 static void s3c24xx_serial_rx_dma_complete(void *args)
605 {
606 struct s3c24xx_uart_port *ourport = args;
607 struct uart_port *port = &ourport->port;
608
609 struct s3c24xx_uart_dma *dma = ourport->dma;
610 struct tty_port *t = &port->state->port;
611 struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
612
613 struct dma_tx_state state;
614 unsigned long flags;
615 int received;
616
617 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
618 received = dma->rx_bytes_requested - state.residue;
619 async_tx_ack(dma->rx_desc);
620
621 uart_port_lock_irqsave(port, &flags);
622
623 if (received)
624 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
625
626 if (tty) {
627 tty_flip_buffer_push(t);
628 tty_kref_put(tty);
629 }
630
631 s3c64xx_start_rx_dma(ourport);
632
633 uart_port_unlock_irqrestore(port, flags);
634 }
635
s3c64xx_start_rx_dma(struct s3c24xx_uart_port * ourport)636 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)
637 {
638 struct s3c24xx_uart_dma *dma = ourport->dma;
639
640 dma_sync_single_for_device(dma->rx_chan->device->dev, dma->rx_addr,
641 dma->rx_size, DMA_FROM_DEVICE);
642
643 dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,
644 dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,
645 DMA_PREP_INTERRUPT);
646 if (!dma->rx_desc) {
647 dev_err(ourport->port.dev, "Unable to get desc for Rx\n");
648 return;
649 }
650
651 dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;
652 dma->rx_desc->callback_param = ourport;
653 dma->rx_bytes_requested = dma->rx_size;
654
655 dma->rx_cookie = dmaengine_submit(dma->rx_desc);
656 dma_async_issue_pending(dma->rx_chan);
657 }
658
659 /* ? - where has parity gone?? */
660 #define S3C2410_UERSTAT_PARITY (0x1000)
661
enable_rx_dma(struct s3c24xx_uart_port * ourport)662 static void enable_rx_dma(struct s3c24xx_uart_port *ourport)
663 {
664 struct uart_port *port = &ourport->port;
665 u32 ucon;
666
667 /* set Rx mode to DMA mode */
668 ucon = rd_regl(port, S3C2410_UCON);
669 ucon &= ~(S3C64XX_UCON_RXBURST_MASK |
670 S3C64XX_UCON_TIMEOUT_MASK |
671 S3C64XX_UCON_EMPTYINT_EN |
672 S3C64XX_UCON_DMASUS_EN |
673 S3C64XX_UCON_TIMEOUT_EN |
674 S3C64XX_UCON_RXMODE_MASK);
675 ucon |= S3C64XX_UCON_RXBURST_1 |
676 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
677 S3C64XX_UCON_EMPTYINT_EN |
678 S3C64XX_UCON_TIMEOUT_EN |
679 S3C64XX_UCON_RXMODE_DMA;
680 wr_regl(port, S3C2410_UCON, ucon);
681
682 ourport->rx_mode = S3C24XX_RX_DMA;
683 }
684
enable_rx_pio(struct s3c24xx_uart_port * ourport)685 static void enable_rx_pio(struct s3c24xx_uart_port *ourport)
686 {
687 struct uart_port *port = &ourport->port;
688 u32 ucon;
689
690 /* set Rx mode to DMA mode */
691 ucon = rd_regl(port, S3C2410_UCON);
692 ucon &= ~S3C64XX_UCON_RXMODE_MASK;
693 ucon |= S3C64XX_UCON_RXMODE_CPU;
694
695 /* Apple types use these bits for IRQ masks */
696 if (ourport->info->type != TYPE_APPLE_S5L) {
697 ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |
698 S3C64XX_UCON_EMPTYINT_EN |
699 S3C64XX_UCON_DMASUS_EN |
700 S3C64XX_UCON_TIMEOUT_EN);
701 ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
702 S3C64XX_UCON_TIMEOUT_EN;
703 }
704 wr_regl(port, S3C2410_UCON, ucon);
705
706 ourport->rx_mode = S3C24XX_RX_PIO;
707 }
708
709 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
710
s3c24xx_serial_rx_chars_dma(struct s3c24xx_uart_port * ourport)711 static irqreturn_t s3c24xx_serial_rx_chars_dma(struct s3c24xx_uart_port *ourport)
712 {
713 struct uart_port *port = &ourport->port;
714 struct s3c24xx_uart_dma *dma = ourport->dma;
715 struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
716 struct tty_port *t = &port->state->port;
717 struct dma_tx_state state;
718 unsigned int received;
719 u32 utrstat;
720
721 utrstat = rd_regl(port, S3C2410_UTRSTAT);
722 rd_regl(port, S3C2410_UFSTAT);
723
724 uart_port_lock(port);
725
726 if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
727 s3c64xx_start_rx_dma(ourport);
728 if (ourport->rx_mode == S3C24XX_RX_PIO)
729 enable_rx_dma(ourport);
730 goto finish;
731 }
732
733 if (ourport->rx_mode == S3C24XX_RX_DMA) {
734 dmaengine_pause(dma->rx_chan);
735 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
736 dmaengine_terminate_all(dma->rx_chan);
737 received = dma->rx_bytes_requested - state.residue;
738 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
739
740 enable_rx_pio(ourport);
741 }
742
743 s3c24xx_serial_rx_drain_fifo(ourport);
744
745 if (tty) {
746 tty_flip_buffer_push(t);
747 tty_kref_put(tty);
748 }
749
750 wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
751
752 finish:
753 uart_port_unlock(port);
754
755 return IRQ_HANDLED;
756 }
757
s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port * ourport)758 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
759 {
760 struct uart_port *port = &ourport->port;
761 unsigned int max_count = port->fifosize;
762 unsigned int fifocnt = 0;
763 u32 ufcon, ufstat, uerstat;
764 u8 ch, flag;
765
766 while (max_count-- > 0) {
767 /*
768 * Receive all characters known to be in FIFO
769 * before reading FIFO level again
770 */
771 if (fifocnt == 0) {
772 ufstat = rd_regl(port, S3C2410_UFSTAT);
773 fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
774 if (fifocnt == 0)
775 break;
776 }
777 fifocnt--;
778
779 uerstat = rd_regl(port, S3C2410_UERSTAT);
780 ch = rd_reg(port, S3C2410_URXH);
781
782 if (port->flags & UPF_CONS_FLOW) {
783 bool txe = s3c24xx_serial_txempty_nofifo(port);
784
785 if (ourport->rx_enabled) {
786 if (!txe) {
787 ourport->rx_enabled = 0;
788 continue;
789 }
790 } else {
791 if (txe) {
792 ufcon = rd_regl(port, S3C2410_UFCON);
793 ufcon |= S3C2410_UFCON_RESETRX;
794 wr_regl(port, S3C2410_UFCON, ufcon);
795 ourport->rx_enabled = 1;
796 return;
797 }
798 continue;
799 }
800 }
801
802 /* insert the character into the buffer */
803
804 flag = TTY_NORMAL;
805 port->icount.rx++;
806
807 if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
808 dev_dbg(port->dev,
809 "rxerr: port ch=0x%02x, rxs=0x%08x\n",
810 ch, uerstat);
811
812 /* check for break */
813 if (uerstat & S3C2410_UERSTAT_BREAK) {
814 dev_dbg(port->dev, "break!\n");
815 port->icount.brk++;
816 if (uart_handle_break(port))
817 continue; /* Ignore character */
818 }
819
820 if (uerstat & S3C2410_UERSTAT_FRAME)
821 port->icount.frame++;
822 if (uerstat & S3C2410_UERSTAT_OVERRUN)
823 port->icount.overrun++;
824
825 uerstat &= port->read_status_mask;
826
827 if (uerstat & S3C2410_UERSTAT_BREAK)
828 flag = TTY_BREAK;
829 else if (uerstat & S3C2410_UERSTAT_PARITY)
830 flag = TTY_PARITY;
831 else if (uerstat & (S3C2410_UERSTAT_FRAME |
832 S3C2410_UERSTAT_OVERRUN))
833 flag = TTY_FRAME;
834 }
835
836 if (uart_handle_sysrq_char(port, ch))
837 continue; /* Ignore character */
838
839 uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
840 ch, flag);
841 }
842
843 tty_flip_buffer_push(&port->state->port);
844 }
845
s3c24xx_serial_rx_chars_pio(struct s3c24xx_uart_port * ourport)846 static irqreturn_t s3c24xx_serial_rx_chars_pio(struct s3c24xx_uart_port *ourport)
847 {
848 struct uart_port *port = &ourport->port;
849
850 uart_port_lock(port);
851 s3c24xx_serial_rx_drain_fifo(ourport);
852 uart_port_unlock(port);
853
854 return IRQ_HANDLED;
855 }
856
s3c24xx_serial_rx_irq(struct s3c24xx_uart_port * ourport)857 static irqreturn_t s3c24xx_serial_rx_irq(struct s3c24xx_uart_port *ourport)
858 {
859 if (ourport->dma && ourport->dma->rx_chan)
860 return s3c24xx_serial_rx_chars_dma(ourport);
861 return s3c24xx_serial_rx_chars_pio(ourport);
862 }
863
s3c24xx_serial_tx_chars(struct s3c24xx_uart_port * ourport)864 static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport)
865 {
866 struct uart_port *port = &ourport->port;
867 struct tty_port *tport = &port->state->port;
868 unsigned int count, dma_count = 0, tail;
869
870 count = kfifo_out_linear(&tport->xmit_fifo, &tail, UART_XMIT_SIZE);
871
872 if (ourport->dma && ourport->dma->tx_chan &&
873 count >= ourport->min_dma_size) {
874 int align = dma_get_cache_alignment() -
875 (tail & (dma_get_cache_alignment() - 1));
876 if (count - align >= ourport->min_dma_size) {
877 dma_count = count - align;
878 count = align;
879 tail += align;
880 }
881 }
882
883 if (port->x_char) {
884 wr_reg(port, S3C2410_UTXH, port->x_char);
885 port->icount.tx++;
886 port->x_char = 0;
887 return;
888 }
889
890 /* if there isn't anything more to transmit, or the uart is now
891 * stopped, disable the uart and exit
892 */
893
894 if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) {
895 s3c24xx_serial_stop_tx(port);
896 return;
897 }
898
899 /* try and drain the buffer... */
900
901 if (count > port->fifosize) {
902 count = port->fifosize;
903 dma_count = 0;
904 }
905
906 while (!(rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)) {
907 unsigned char ch;
908
909 if (!uart_fifo_get(port, &ch))
910 break;
911
912 wr_reg(port, S3C2410_UTXH, ch);
913 count--;
914 }
915
916 if (!count && dma_count) {
917 s3c24xx_serial_start_tx_dma(ourport, dma_count, tail);
918 return;
919 }
920
921 if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
922 uart_write_wakeup(port);
923
924 if (kfifo_is_empty(&tport->xmit_fifo))
925 s3c24xx_serial_stop_tx(port);
926 }
927
s3c24xx_serial_tx_irq(struct s3c24xx_uart_port * ourport)928 static irqreturn_t s3c24xx_serial_tx_irq(struct s3c24xx_uart_port *ourport)
929 {
930 struct uart_port *port = &ourport->port;
931
932 uart_port_lock(port);
933
934 s3c24xx_serial_tx_chars(ourport);
935
936 uart_port_unlock(port);
937 return IRQ_HANDLED;
938 }
939
940 /* interrupt handler for s3c64xx and later SoC's.*/
s3c64xx_serial_handle_irq(int irq,void * id)941 static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)
942 {
943 struct s3c24xx_uart_port *ourport = id;
944 const struct uart_port *port = &ourport->port;
945 u32 pend = rd_regl(port, S3C64XX_UINTP);
946 irqreturn_t ret = IRQ_HANDLED;
947
948 if (pend & S3C64XX_UINTM_RXD_MSK) {
949 ret = s3c24xx_serial_rx_irq(ourport);
950 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);
951 }
952 if (pend & S3C64XX_UINTM_TXD_MSK) {
953 ret = s3c24xx_serial_tx_irq(ourport);
954 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);
955 }
956 return ret;
957 }
958
959 /* interrupt handler for Apple SoC's.*/
apple_serial_handle_irq(int irq,void * id)960 static irqreturn_t apple_serial_handle_irq(int irq, void *id)
961 {
962 struct s3c24xx_uart_port *ourport = id;
963 const struct uart_port *port = &ourport->port;
964 u32 pend = rd_regl(port, S3C2410_UTRSTAT);
965 irqreturn_t ret = IRQ_NONE;
966
967 if (pend & (APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO |
968 APPLE_S5L_UTRSTAT_RXTO_LEGACY)) {
969 wr_regl(port, S3C2410_UTRSTAT,
970 APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO |
971 APPLE_S5L_UTRSTAT_RXTO_LEGACY);
972 ret = s3c24xx_serial_rx_irq(ourport);
973 }
974 if (pend & APPLE_S5L_UTRSTAT_TXTHRESH) {
975 wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_TXTHRESH);
976 ret = s3c24xx_serial_tx_irq(ourport);
977 }
978
979 return ret;
980 }
981
s3c24xx_serial_tx_empty(struct uart_port * port)982 static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
983 {
984 const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
985 u32 ufstat = rd_regl(port, S3C2410_UFSTAT);
986 u32 ufcon = rd_regl(port, S3C2410_UFCON);
987
988 if (ufcon & S3C2410_UFCON_FIFOMODE) {
989 if ((ufstat & info->tx_fifomask) ||
990 (ufstat & info->tx_fifofull))
991 return 0;
992 return TIOCSER_TEMT;
993 }
994
995 return s3c24xx_serial_txempty_nofifo(port) ? TIOCSER_TEMT : 0;
996 }
997
998 /* no modem control lines */
s3c24xx_serial_get_mctrl(struct uart_port * port)999 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
1000 {
1001 u32 umstat = rd_reg(port, S3C2410_UMSTAT);
1002
1003 if (umstat & S3C2410_UMSTAT_CTS)
1004 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
1005 else
1006 return TIOCM_CAR | TIOCM_DSR;
1007 }
1008
s3c24xx_serial_set_mctrl(struct uart_port * port,unsigned int mctrl)1009 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
1010 {
1011 u32 umcon = rd_regl(port, S3C2410_UMCON);
1012 u32 ucon = rd_regl(port, S3C2410_UCON);
1013
1014 if (mctrl & TIOCM_RTS)
1015 umcon |= S3C2410_UMCOM_RTS_LOW;
1016 else
1017 umcon &= ~S3C2410_UMCOM_RTS_LOW;
1018
1019 wr_regl(port, S3C2410_UMCON, umcon);
1020
1021 if (mctrl & TIOCM_LOOP)
1022 ucon |= S3C2410_UCON_LOOPBACK;
1023 else
1024 ucon &= ~S3C2410_UCON_LOOPBACK;
1025
1026 wr_regl(port, S3C2410_UCON, ucon);
1027 }
1028
s3c24xx_serial_break_ctl(struct uart_port * port,int break_state)1029 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
1030 {
1031 unsigned long flags;
1032 u32 ucon;
1033
1034 uart_port_lock_irqsave(port, &flags);
1035
1036 ucon = rd_regl(port, S3C2410_UCON);
1037
1038 if (break_state)
1039 ucon |= S3C2410_UCON_SBREAK;
1040 else
1041 ucon &= ~S3C2410_UCON_SBREAK;
1042
1043 wr_regl(port, S3C2410_UCON, ucon);
1044
1045 uart_port_unlock_irqrestore(port, flags);
1046 }
1047
s3c24xx_serial_request_dma(struct s3c24xx_uart_port * p)1048 static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
1049 {
1050 struct s3c24xx_uart_dma *dma = p->dma;
1051 struct dma_slave_caps dma_caps;
1052 const char *reason = NULL;
1053 int ret;
1054
1055 /* Default slave configuration parameters */
1056 dma->rx_conf.direction = DMA_DEV_TO_MEM;
1057 dma->rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1058 dma->rx_conf.src_addr = p->port.mapbase + S3C2410_URXH;
1059 dma->rx_conf.src_maxburst = 1;
1060
1061 dma->tx_conf.direction = DMA_MEM_TO_DEV;
1062 dma->tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1063 dma->tx_conf.dst_addr = p->port.mapbase + S3C2410_UTXH;
1064 dma->tx_conf.dst_maxburst = 1;
1065
1066 dma->rx_chan = dma_request_chan(p->port.dev, "rx");
1067
1068 if (IS_ERR(dma->rx_chan)) {
1069 reason = "DMA RX channel request failed";
1070 ret = PTR_ERR(dma->rx_chan);
1071 goto err_warn;
1072 }
1073
1074 ret = dma_get_slave_caps(dma->rx_chan, &dma_caps);
1075 if (ret < 0 ||
1076 dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
1077 reason = "insufficient DMA RX engine capabilities";
1078 ret = -EOPNOTSUPP;
1079 goto err_release_rx;
1080 }
1081
1082 dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);
1083
1084 dma->tx_chan = dma_request_chan(p->port.dev, "tx");
1085 if (IS_ERR(dma->tx_chan)) {
1086 reason = "DMA TX channel request failed";
1087 ret = PTR_ERR(dma->tx_chan);
1088 goto err_release_rx;
1089 }
1090
1091 ret = dma_get_slave_caps(dma->tx_chan, &dma_caps);
1092 if (ret < 0 ||
1093 dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
1094 reason = "insufficient DMA TX engine capabilities";
1095 ret = -EOPNOTSUPP;
1096 goto err_release_tx;
1097 }
1098
1099 dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
1100
1101 /* RX buffer */
1102 dma->rx_size = PAGE_SIZE;
1103
1104 dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
1105 if (!dma->rx_buf) {
1106 ret = -ENOMEM;
1107 goto err_release_tx;
1108 }
1109
1110 dma->rx_addr = dma_map_single(dma->rx_chan->device->dev, dma->rx_buf,
1111 dma->rx_size, DMA_FROM_DEVICE);
1112 if (dma_mapping_error(dma->rx_chan->device->dev, dma->rx_addr)) {
1113 reason = "DMA mapping error for RX buffer";
1114 ret = -EIO;
1115 goto err_free_rx;
1116 }
1117
1118 /* TX buffer */
1119 dma->tx_addr = dma_map_single(dma->tx_chan->device->dev,
1120 p->port.state->port.xmit_buf,
1121 UART_XMIT_SIZE,
1122 DMA_TO_DEVICE);
1123 if (dma_mapping_error(dma->tx_chan->device->dev, dma->tx_addr)) {
1124 reason = "DMA mapping error for TX buffer";
1125 ret = -EIO;
1126 goto err_unmap_rx;
1127 }
1128
1129 return 0;
1130
1131 err_unmap_rx:
1132 dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr,
1133 dma->rx_size, DMA_FROM_DEVICE);
1134 err_free_rx:
1135 kfree(dma->rx_buf);
1136 err_release_tx:
1137 dma_release_channel(dma->tx_chan);
1138 err_release_rx:
1139 dma_release_channel(dma->rx_chan);
1140 err_warn:
1141 if (reason)
1142 dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);
1143 return ret;
1144 }
1145
s3c24xx_serial_release_dma(struct s3c24xx_uart_port * p)1146 static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)
1147 {
1148 struct s3c24xx_uart_dma *dma = p->dma;
1149
1150 if (dma->rx_chan) {
1151 dmaengine_terminate_all(dma->rx_chan);
1152 dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr,
1153 dma->rx_size, DMA_FROM_DEVICE);
1154 kfree(dma->rx_buf);
1155 dma_release_channel(dma->rx_chan);
1156 dma->rx_chan = NULL;
1157 }
1158
1159 if (dma->tx_chan) {
1160 dmaengine_terminate_all(dma->tx_chan);
1161 dma_unmap_single(dma->tx_chan->device->dev, dma->tx_addr,
1162 UART_XMIT_SIZE, DMA_TO_DEVICE);
1163 dma_release_channel(dma->tx_chan);
1164 dma->tx_chan = NULL;
1165 }
1166 }
1167
s3c64xx_serial_shutdown(struct uart_port * port)1168 static void s3c64xx_serial_shutdown(struct uart_port *port)
1169 {
1170 struct s3c24xx_uart_port *ourport = to_ourport(port);
1171
1172 ourport->tx_enabled = 0;
1173 ourport->tx_mode = 0;
1174 ourport->rx_enabled = 0;
1175
1176 free_irq(port->irq, ourport);
1177
1178 wr_regl(port, S3C64XX_UINTP, 0xf);
1179 wr_regl(port, S3C64XX_UINTM, 0xf);
1180
1181 if (ourport->dma)
1182 s3c24xx_serial_release_dma(ourport);
1183
1184 ourport->tx_in_progress = 0;
1185 }
1186
apple_s5l_serial_shutdown(struct uart_port * port)1187 static void apple_s5l_serial_shutdown(struct uart_port *port)
1188 {
1189 struct s3c24xx_uart_port *ourport = to_ourport(port);
1190
1191 u32 ucon;
1192
1193 ucon = rd_regl(port, S3C2410_UCON);
1194 ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |
1195 APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
1196 APPLE_S5L_UCON_RXTO_ENA_MSK |
1197 APPLE_S5L_UCON_RXTO_LEGACY_ENA_MSK);
1198 wr_regl(port, S3C2410_UCON, ucon);
1199
1200 wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);
1201
1202 free_irq(port->irq, ourport);
1203
1204 ourport->tx_enabled = 0;
1205 ourport->tx_mode = 0;
1206 ourport->rx_enabled = 0;
1207
1208 if (ourport->dma)
1209 s3c24xx_serial_release_dma(ourport);
1210
1211 ourport->tx_in_progress = 0;
1212 }
1213
s3c64xx_serial_startup(struct uart_port * port)1214 static int s3c64xx_serial_startup(struct uart_port *port)
1215 {
1216 struct s3c24xx_uart_port *ourport = to_ourport(port);
1217 unsigned long flags;
1218 u32 ufcon;
1219 int ret;
1220
1221 wr_regl(port, S3C64XX_UINTM, 0xf);
1222 if (ourport->dma) {
1223 ret = s3c24xx_serial_request_dma(ourport);
1224 if (ret < 0) {
1225 devm_kfree(port->dev, ourport->dma);
1226 ourport->dma = NULL;
1227 }
1228 }
1229
1230 ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
1231 s3c24xx_serial_portname(port), ourport);
1232 if (ret) {
1233 dev_err(port->dev, "cannot get irq %d\n", port->irq);
1234 return ret;
1235 }
1236
1237 /* For compatibility with s3c24xx Soc's */
1238 ourport->rx_enabled = 1;
1239 ourport->tx_enabled = 0;
1240
1241 uart_port_lock_irqsave(port, &flags);
1242
1243 ufcon = rd_regl(port, S3C2410_UFCON);
1244 ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
1245 if (!uart_console(port))
1246 ufcon |= S3C2410_UFCON_RESETTX;
1247 wr_regl(port, S3C2410_UFCON, ufcon);
1248
1249 enable_rx_pio(ourport);
1250
1251 uart_port_unlock_irqrestore(port, flags);
1252
1253 /* Enable Rx Interrupt */
1254 s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);
1255
1256 return ret;
1257 }
1258
apple_s5l_serial_startup(struct uart_port * port)1259 static int apple_s5l_serial_startup(struct uart_port *port)
1260 {
1261 struct s3c24xx_uart_port *ourport = to_ourport(port);
1262 unsigned long flags;
1263 u32 ufcon;
1264 int ret;
1265
1266 wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);
1267
1268 ret = request_irq(port->irq, apple_serial_handle_irq, 0,
1269 s3c24xx_serial_portname(port), ourport);
1270 if (ret) {
1271 dev_err(port->dev, "cannot get irq %d\n", port->irq);
1272 return ret;
1273 }
1274
1275 /* For compatibility with s3c24xx Soc's */
1276 ourport->rx_enabled = 1;
1277 ourport->tx_enabled = 0;
1278
1279 uart_port_lock_irqsave(port, &flags);
1280
1281 ufcon = rd_regl(port, S3C2410_UFCON);
1282 ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
1283 if (!uart_console(port))
1284 ufcon |= S3C2410_UFCON_RESETTX;
1285 wr_regl(port, S3C2410_UFCON, ufcon);
1286
1287 enable_rx_pio(ourport);
1288
1289 uart_port_unlock_irqrestore(port, flags);
1290
1291 /* Enable Rx Interrupt */
1292 s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON);
1293 s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON);
1294 s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTO_LEGACY_ENA, S3C2410_UCON);
1295
1296 return ret;
1297 }
1298
s3c24xx_serial_pm(struct uart_port * port,unsigned int level,unsigned int old)1299 static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
1300 unsigned int old)
1301 {
1302 struct s3c24xx_uart_port *ourport = to_ourport(port);
1303 int timeout = 10000;
1304
1305 ourport->pm_level = level;
1306
1307 switch (level) {
1308 case 3:
1309 while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
1310 udelay(100);
1311
1312 if (!IS_ERR(ourport->baudclk))
1313 clk_disable_unprepare(ourport->baudclk);
1314
1315 clk_disable_unprepare(ourport->clk);
1316 break;
1317
1318 case 0:
1319 clk_prepare_enable(ourport->clk);
1320
1321 if (!IS_ERR(ourport->baudclk))
1322 clk_prepare_enable(ourport->baudclk);
1323 break;
1324 default:
1325 dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);
1326 }
1327 }
1328
1329 /* baud rate calculation
1330 *
1331 * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
1332 * of different sources, including the peripheral clock ("pclk") and an
1333 * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
1334 * with a programmable extra divisor.
1335 *
1336 * The following code goes through the clock sources, and calculates the
1337 * baud clocks (and the resultant actual baud rates) and then tries to
1338 * pick the closest one and select that.
1339 *
1340 */
1341
1342 #define MAX_CLK_NAME_LENGTH 15
1343
s3c24xx_serial_getsource(struct uart_port * port)1344 static inline u8 s3c24xx_serial_getsource(struct uart_port *port)
1345 {
1346 const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1347 u32 ucon;
1348
1349 if (info->num_clks == 1)
1350 return 0;
1351
1352 ucon = rd_regl(port, S3C2410_UCON);
1353 ucon &= info->clksel_mask;
1354 return ucon >> info->clksel_shift;
1355 }
1356
s3c24xx_serial_setsource(struct uart_port * port,u8 clk_sel)1357 static void s3c24xx_serial_setsource(struct uart_port *port, u8 clk_sel)
1358 {
1359 const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1360 u32 ucon;
1361
1362 if (info->num_clks == 1)
1363 return;
1364
1365 ucon = rd_regl(port, S3C2410_UCON);
1366 if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel)
1367 return;
1368
1369 ucon &= ~info->clksel_mask;
1370 ucon |= clk_sel << info->clksel_shift;
1371 wr_regl(port, S3C2410_UCON, ucon);
1372 }
1373
s3c24xx_serial_getclk(struct s3c24xx_uart_port * ourport,unsigned int req_baud,struct clk ** best_clk,u8 * clk_num)1374 static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
1375 unsigned int req_baud, struct clk **best_clk,
1376 u8 *clk_num)
1377 {
1378 const struct s3c24xx_uart_info *info = ourport->info;
1379 struct clk *clk;
1380 unsigned long rate;
1381 unsigned int baud, quot, best_quot = 0;
1382 char clkname[MAX_CLK_NAME_LENGTH];
1383 int calc_deviation, deviation = (1 << 30) - 1;
1384 u8 cnt;
1385
1386 for (cnt = 0; cnt < info->num_clks; cnt++) {
1387 /* Keep selected clock if provided */
1388 if (ourport->cfg->clk_sel &&
1389 !(ourport->cfg->clk_sel & (1 << cnt)))
1390 continue;
1391
1392 sprintf(clkname, "clk_uart_baud%d", cnt);
1393 clk = clk_get(ourport->port.dev, clkname);
1394 if (IS_ERR(clk))
1395 continue;
1396
1397 rate = clk_get_rate(clk);
1398 if (!rate) {
1399 dev_err(ourport->port.dev,
1400 "Failed to get clock rate for %s.\n", clkname);
1401 clk_put(clk);
1402 continue;
1403 }
1404
1405 if (ourport->info->has_divslot) {
1406 unsigned long div = rate / req_baud;
1407
1408 /* The UDIVSLOT register on the newer UARTs allows us to
1409 * get a divisor adjustment of 1/16th on the baud clock.
1410 *
1411 * We don't keep the UDIVSLOT value (the 16ths we
1412 * calculated by not multiplying the baud by 16) as it
1413 * is easy enough to recalculate.
1414 */
1415
1416 quot = div / 16;
1417 baud = rate / div;
1418 } else {
1419 quot = (rate + (8 * req_baud)) / (16 * req_baud);
1420 baud = rate / (quot * 16);
1421 }
1422 quot--;
1423
1424 calc_deviation = abs(req_baud - baud);
1425
1426 if (calc_deviation < deviation) {
1427 /*
1428 * If we find a better clk, release the previous one, if
1429 * any.
1430 */
1431 if (!IS_ERR(*best_clk))
1432 clk_put(*best_clk);
1433 *best_clk = clk;
1434 best_quot = quot;
1435 *clk_num = cnt;
1436 deviation = calc_deviation;
1437 } else {
1438 clk_put(clk);
1439 }
1440 }
1441
1442 return best_quot;
1443 }
1444
1445 /* udivslot_table[]
1446 *
1447 * This table takes the fractional value of the baud divisor and gives
1448 * the recommended setting for the UDIVSLOT register.
1449 */
1450 static const u16 udivslot_table[16] = {
1451 [0] = 0x0000,
1452 [1] = 0x0080,
1453 [2] = 0x0808,
1454 [3] = 0x0888,
1455 [4] = 0x2222,
1456 [5] = 0x4924,
1457 [6] = 0x4A52,
1458 [7] = 0x54AA,
1459 [8] = 0x5555,
1460 [9] = 0xD555,
1461 [10] = 0xD5D5,
1462 [11] = 0xDDD5,
1463 [12] = 0xDDDD,
1464 [13] = 0xDFDD,
1465 [14] = 0xDFDF,
1466 [15] = 0xFFDF,
1467 };
1468
s3c24xx_serial_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)1469 static void s3c24xx_serial_set_termios(struct uart_port *port,
1470 struct ktermios *termios,
1471 const struct ktermios *old)
1472 {
1473 const struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
1474 struct s3c24xx_uart_port *ourport = to_ourport(port);
1475 struct clk *clk = ERR_PTR(-EINVAL);
1476 unsigned long flags;
1477 unsigned int baud, quot;
1478 unsigned int udivslot = 0;
1479 u32 ulcon, umcon;
1480 u8 clk_sel = 0;
1481
1482 /*
1483 * We don't support modem control lines.
1484 */
1485 termios->c_cflag &= ~(HUPCL | CMSPAR);
1486 termios->c_cflag |= CLOCAL;
1487
1488 /*
1489 * Ask the core to calculate the divisor for us.
1490 */
1491
1492 baud = uart_get_baud_rate(port, termios, old, 0, 3000000);
1493 quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);
1494 if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
1495 quot = port->custom_divisor;
1496 if (IS_ERR(clk))
1497 return;
1498
1499 /* check to see if we need to change clock source */
1500
1501 if (ourport->baudclk != clk) {
1502 clk_prepare_enable(clk);
1503
1504 s3c24xx_serial_setsource(port, clk_sel);
1505
1506 if (!IS_ERR(ourport->baudclk)) {
1507 clk_disable_unprepare(ourport->baudclk);
1508 ourport->baudclk = ERR_PTR(-EINVAL);
1509 }
1510
1511 ourport->baudclk = clk;
1512 ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
1513 }
1514
1515 if (ourport->info->has_divslot) {
1516 unsigned int div = ourport->baudclk_rate / baud;
1517
1518 if (cfg->has_fracval) {
1519 udivslot = (div & 15);
1520 dev_dbg(port->dev, "fracval = %04x\n", udivslot);
1521 } else {
1522 udivslot = udivslot_table[div & 15];
1523 dev_dbg(port->dev, "udivslot = %04x (div %d)\n",
1524 udivslot, div & 15);
1525 }
1526 }
1527
1528 switch (termios->c_cflag & CSIZE) {
1529 case CS5:
1530 dev_dbg(port->dev, "config: 5bits/char\n");
1531 ulcon = S3C2410_LCON_CS5;
1532 break;
1533 case CS6:
1534 dev_dbg(port->dev, "config: 6bits/char\n");
1535 ulcon = S3C2410_LCON_CS6;
1536 break;
1537 case CS7:
1538 dev_dbg(port->dev, "config: 7bits/char\n");
1539 ulcon = S3C2410_LCON_CS7;
1540 break;
1541 case CS8:
1542 default:
1543 dev_dbg(port->dev, "config: 8bits/char\n");
1544 ulcon = S3C2410_LCON_CS8;
1545 break;
1546 }
1547
1548 /* preserve original lcon IR settings */
1549 ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
1550
1551 if (termios->c_cflag & CSTOPB)
1552 ulcon |= S3C2410_LCON_STOPB;
1553
1554 if (termios->c_cflag & PARENB) {
1555 if (termios->c_cflag & PARODD)
1556 ulcon |= S3C2410_LCON_PODD;
1557 else
1558 ulcon |= S3C2410_LCON_PEVEN;
1559 } else {
1560 ulcon |= S3C2410_LCON_PNONE;
1561 }
1562
1563 uart_port_lock_irqsave(port, &flags);
1564
1565 dev_dbg(port->dev,
1566 "setting ulcon to %08x, brddiv to %d, udivslot %08x\n",
1567 ulcon, quot, udivslot);
1568
1569 wr_regl(port, S3C2410_ULCON, ulcon);
1570 wr_regl(port, S3C2410_UBRDIV, quot);
1571
1572 port->status &= ~UPSTAT_AUTOCTS;
1573
1574 umcon = rd_regl(port, S3C2410_UMCON);
1575 if (termios->c_cflag & CRTSCTS) {
1576 umcon |= S3C2410_UMCOM_AFC;
1577 /* Disable RTS when RX FIFO contains 63 bytes */
1578 umcon &= ~S3C2412_UMCON_AFC_8;
1579 port->status = UPSTAT_AUTOCTS;
1580 } else {
1581 umcon &= ~S3C2410_UMCOM_AFC;
1582 }
1583 wr_regl(port, S3C2410_UMCON, umcon);
1584
1585 if (ourport->info->has_divslot)
1586 wr_regl(port, S3C2443_DIVSLOT, udivslot);
1587
1588 dev_dbg(port->dev,
1589 "uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
1590 rd_regl(port, S3C2410_ULCON),
1591 rd_regl(port, S3C2410_UCON),
1592 rd_regl(port, S3C2410_UFCON));
1593
1594 /*
1595 * Update the per-port timeout.
1596 */
1597 uart_update_timeout(port, termios->c_cflag, baud);
1598
1599 /*
1600 * Which character status flags are we interested in?
1601 */
1602 port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
1603 if (termios->c_iflag & INPCK)
1604 port->read_status_mask |= S3C2410_UERSTAT_FRAME |
1605 S3C2410_UERSTAT_PARITY;
1606 /*
1607 * Which character status flags should we ignore?
1608 */
1609 port->ignore_status_mask = 0;
1610 if (termios->c_iflag & IGNPAR)
1611 port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
1612 if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
1613 port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
1614
1615 /*
1616 * Ignore all characters if CREAD is not set.
1617 */
1618 if ((termios->c_cflag & CREAD) == 0)
1619 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
1620
1621 uart_port_unlock_irqrestore(port, flags);
1622 }
1623
s3c24xx_serial_type(struct uart_port * port)1624 static const char *s3c24xx_serial_type(struct uart_port *port)
1625 {
1626 const struct s3c24xx_uart_port *ourport = to_ourport(port);
1627
1628 switch (ourport->info->type) {
1629 case TYPE_S3C6400:
1630 return "S3C6400/10";
1631 case TYPE_APPLE_S5L:
1632 return "APPLE S5L";
1633 default:
1634 return NULL;
1635 }
1636 }
1637
s3c24xx_serial_config_port(struct uart_port * port,int flags)1638 static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
1639 {
1640 const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1641
1642 if (flags & UART_CONFIG_TYPE)
1643 port->type = info->port_type;
1644 }
1645
1646 /*
1647 * verify the new serial_struct (for TIOCSSERIAL).
1648 */
1649 static int
s3c24xx_serial_verify_port(struct uart_port * port,struct serial_struct * ser)1650 s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
1651 {
1652 const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1653
1654 if (ser->type != PORT_UNKNOWN && ser->type != info->port_type)
1655 return -EINVAL;
1656
1657 return 0;
1658 }
1659
1660 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1661
1662 static struct console s3c24xx_serial_console;
1663
s3c24xx_serial_register_console(void)1664 static void __init s3c24xx_serial_register_console(void)
1665 {
1666 register_console(&s3c24xx_serial_console);
1667 }
1668
s3c24xx_serial_unregister_console(void)1669 static void s3c24xx_serial_unregister_console(void)
1670 {
1671 if (console_is_registered(&s3c24xx_serial_console))
1672 unregister_console(&s3c24xx_serial_console);
1673 }
1674
1675 #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
1676 #else
s3c24xx_serial_register_console(void)1677 static inline void s3c24xx_serial_register_console(void) { }
s3c24xx_serial_unregister_console(void)1678 static inline void s3c24xx_serial_unregister_console(void) { }
1679 #define S3C24XX_SERIAL_CONSOLE NULL
1680 #endif
1681
1682 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1683 static int s3c24xx_serial_get_poll_char(struct uart_port *port);
1684 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1685 unsigned char c);
1686 #endif
1687
1688 static const struct uart_ops s3c64xx_serial_ops = {
1689 .pm = s3c24xx_serial_pm,
1690 .tx_empty = s3c24xx_serial_tx_empty,
1691 .get_mctrl = s3c24xx_serial_get_mctrl,
1692 .set_mctrl = s3c24xx_serial_set_mctrl,
1693 .stop_tx = s3c24xx_serial_stop_tx,
1694 .start_tx = s3c24xx_serial_start_tx,
1695 .stop_rx = s3c24xx_serial_stop_rx,
1696 .break_ctl = s3c24xx_serial_break_ctl,
1697 .startup = s3c64xx_serial_startup,
1698 .shutdown = s3c64xx_serial_shutdown,
1699 .set_termios = s3c24xx_serial_set_termios,
1700 .type = s3c24xx_serial_type,
1701 .config_port = s3c24xx_serial_config_port,
1702 .verify_port = s3c24xx_serial_verify_port,
1703 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1704 .poll_get_char = s3c24xx_serial_get_poll_char,
1705 .poll_put_char = s3c24xx_serial_put_poll_char,
1706 #endif
1707 };
1708
1709 static const struct uart_ops apple_s5l_serial_ops = {
1710 .pm = s3c24xx_serial_pm,
1711 .tx_empty = s3c24xx_serial_tx_empty,
1712 .get_mctrl = s3c24xx_serial_get_mctrl,
1713 .set_mctrl = s3c24xx_serial_set_mctrl,
1714 .stop_tx = s3c24xx_serial_stop_tx,
1715 .start_tx = s3c24xx_serial_start_tx,
1716 .stop_rx = s3c24xx_serial_stop_rx,
1717 .break_ctl = s3c24xx_serial_break_ctl,
1718 .startup = apple_s5l_serial_startup,
1719 .shutdown = apple_s5l_serial_shutdown,
1720 .set_termios = s3c24xx_serial_set_termios,
1721 .type = s3c24xx_serial_type,
1722 .config_port = s3c24xx_serial_config_port,
1723 .verify_port = s3c24xx_serial_verify_port,
1724 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1725 .poll_get_char = s3c24xx_serial_get_poll_char,
1726 .poll_put_char = s3c24xx_serial_put_poll_char,
1727 #endif
1728 };
1729
1730 static struct uart_driver s3c24xx_uart_drv = {
1731 .owner = THIS_MODULE,
1732 .driver_name = "s3c2410_serial",
1733 .nr = UART_NR,
1734 .cons = S3C24XX_SERIAL_CONSOLE,
1735 .dev_name = S3C24XX_SERIAL_NAME,
1736 .major = S3C24XX_SERIAL_MAJOR,
1737 .minor = S3C24XX_SERIAL_MINOR,
1738 };
1739
1740 static struct s3c24xx_uart_port s3c24xx_serial_ports[UART_NR];
1741
s3c24xx_serial_init_port_default(int index)1742 static void s3c24xx_serial_init_port_default(int index)
1743 {
1744 struct uart_port *port = &s3c24xx_serial_ports[index].port;
1745
1746 spin_lock_init(&port->lock);
1747
1748 port->uartclk = 0;
1749 port->fifosize = 16;
1750 port->flags = UPF_BOOT_AUTOCONF;
1751 port->line = index;
1752 }
1753
1754 /* s3c24xx_serial_resetport
1755 *
1756 * reset the fifos and other the settings.
1757 */
1758
s3c24xx_serial_resetport(struct uart_port * port,const struct s3c2410_uartcfg * cfg)1759 static void s3c24xx_serial_resetport(struct uart_port *port,
1760 const struct s3c2410_uartcfg *cfg)
1761 {
1762 const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1763 u32 ucon = rd_regl(port, S3C2410_UCON);
1764
1765 ucon &= (info->clksel_mask | info->ucon_mask);
1766 wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);
1767
1768 /* reset both fifos */
1769 wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
1770 wr_regl(port, S3C2410_UFCON, cfg->ufcon);
1771
1772 /* some delay is required after fifo reset */
1773 udelay(1);
1774 }
1775
s3c24xx_serial_enable_baudclk(struct s3c24xx_uart_port * ourport)1776 static int s3c24xx_serial_enable_baudclk(struct s3c24xx_uart_port *ourport)
1777 {
1778 struct device *dev = ourport->port.dev;
1779 const struct s3c24xx_uart_info *info = ourport->info;
1780 char clk_name[MAX_CLK_NAME_LENGTH];
1781 struct clk *clk;
1782 int ret;
1783 u8 clk_sel, clk_num;
1784
1785 clk_sel = ourport->cfg->clk_sel ? : info->def_clk_sel;
1786 for (clk_num = 0; clk_num < info->num_clks; clk_num++) {
1787 if (!(clk_sel & (1 << clk_num)))
1788 continue;
1789
1790 sprintf(clk_name, "clk_uart_baud%d", clk_num);
1791 clk = clk_get(dev, clk_name);
1792 if (IS_ERR(clk))
1793 continue;
1794
1795 ret = clk_prepare_enable(clk);
1796 if (ret) {
1797 clk_put(clk);
1798 continue;
1799 }
1800
1801 ourport->baudclk = clk;
1802 ourport->baudclk_rate = clk_get_rate(clk);
1803 s3c24xx_serial_setsource(&ourport->port, clk_num);
1804
1805 return 0;
1806 }
1807
1808 return -EINVAL;
1809 }
1810
1811 /* s3c24xx_serial_init_port
1812 *
1813 * initialise a single serial port from the platform device given
1814 */
1815
s3c24xx_serial_init_port(struct s3c24xx_uart_port * ourport,struct platform_device * platdev)1816 static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
1817 struct platform_device *platdev)
1818 {
1819 struct uart_port *port = &ourport->port;
1820 const struct s3c2410_uartcfg *cfg = ourport->cfg;
1821 struct resource *res;
1822 int ret;
1823
1824 if (platdev == NULL)
1825 return -ENODEV;
1826
1827 if (port->mapbase != 0)
1828 return -EINVAL;
1829
1830 /* setup info for port */
1831 port->dev = &platdev->dev;
1832
1833 port->uartclk = 1;
1834
1835 if (cfg->uart_flags & UPF_CONS_FLOW) {
1836 dev_dbg(port->dev, "enabling flow control\n");
1837 port->flags |= UPF_CONS_FLOW;
1838 }
1839
1840 /* sort our the physical and virtual addresses for each UART */
1841
1842 res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
1843 if (res == NULL) {
1844 dev_err(port->dev, "failed to find memory resource for uart\n");
1845 return -EINVAL;
1846 }
1847
1848 dev_dbg(port->dev, "resource %pR)\n", res);
1849
1850 port->membase = devm_ioremap_resource(port->dev, res);
1851 if (IS_ERR(port->membase)) {
1852 dev_err(port->dev, "failed to remap controller address\n");
1853 return -EBUSY;
1854 }
1855
1856 port->mapbase = res->start;
1857 ret = platform_get_irq(platdev, 0);
1858 if (ret < 0) {
1859 port->irq = 0;
1860 } else {
1861 port->irq = ret;
1862 ourport->rx_irq = ret;
1863 ourport->tx_irq = ret + 1;
1864 }
1865
1866 /*
1867 * DMA is currently supported only on DT platforms, if DMA properties
1868 * are specified.
1869 */
1870 if (platdev->dev.of_node && of_find_property(platdev->dev.of_node,
1871 "dmas", NULL)) {
1872 ourport->dma = devm_kzalloc(port->dev,
1873 sizeof(*ourport->dma),
1874 GFP_KERNEL);
1875 if (!ourport->dma) {
1876 ret = -ENOMEM;
1877 goto err;
1878 }
1879 }
1880
1881 ourport->clk = clk_get(&platdev->dev, "uart");
1882 if (IS_ERR(ourport->clk)) {
1883 pr_err("%s: Controller clock not found\n",
1884 dev_name(&platdev->dev));
1885 ret = PTR_ERR(ourport->clk);
1886 goto err;
1887 }
1888
1889 ret = clk_prepare_enable(ourport->clk);
1890 if (ret) {
1891 pr_err("uart: clock failed to prepare+enable: %d\n", ret);
1892 clk_put(ourport->clk);
1893 goto err;
1894 }
1895
1896 ret = s3c24xx_serial_enable_baudclk(ourport);
1897 if (ret)
1898 pr_warn("uart: failed to enable baudclk\n");
1899
1900 /* Keep all interrupts masked and cleared */
1901 switch (ourport->info->type) {
1902 case TYPE_S3C6400:
1903 wr_regl(port, S3C64XX_UINTM, 0xf);
1904 wr_regl(port, S3C64XX_UINTP, 0xf);
1905 wr_regl(port, S3C64XX_UINTSP, 0xf);
1906 break;
1907 case TYPE_APPLE_S5L: {
1908 u32 ucon;
1909
1910 ucon = rd_regl(port, S3C2410_UCON);
1911 ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |
1912 APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
1913 APPLE_S5L_UCON_RXTO_ENA_MSK);
1914 wr_regl(port, S3C2410_UCON, ucon);
1915
1916 wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);
1917 break;
1918 }
1919 default:
1920 break;
1921 }
1922
1923 dev_dbg(port->dev, "port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n",
1924 &port->mapbase, port->membase, port->irq,
1925 ourport->rx_irq, ourport->tx_irq, port->uartclk);
1926
1927 /* reset the fifos (and setup the uart) */
1928 s3c24xx_serial_resetport(port, cfg);
1929
1930 return 0;
1931
1932 err:
1933 port->mapbase = 0;
1934 return ret;
1935 }
1936
1937 /* Device driver serial port probe */
1938
1939 static int probe_index;
1940
1941 static inline const struct s3c24xx_serial_drv_data *
s3c24xx_get_driver_data(struct platform_device * pdev)1942 s3c24xx_get_driver_data(struct platform_device *pdev)
1943 {
1944 if (dev_of_node(&pdev->dev))
1945 return of_device_get_match_data(&pdev->dev);
1946
1947 return (struct s3c24xx_serial_drv_data *)
1948 platform_get_device_id(pdev)->driver_data;
1949 }
1950
s3c24xx_serial_probe(struct platform_device * pdev)1951 static int s3c24xx_serial_probe(struct platform_device *pdev)
1952 {
1953 struct device_node *np = pdev->dev.of_node;
1954 struct s3c24xx_uart_port *ourport;
1955 int index = probe_index;
1956 int ret, prop = 0, fifosize_prop = 1;
1957
1958 if (np) {
1959 ret = of_alias_get_id(np, "serial");
1960 if (ret >= 0)
1961 index = ret;
1962 }
1963
1964 if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) {
1965 dev_err(&pdev->dev, "serial%d out of range\n", index);
1966 return -EINVAL;
1967 }
1968 ourport = &s3c24xx_serial_ports[index];
1969
1970 s3c24xx_serial_init_port_default(index);
1971
1972 ourport->drv_data = s3c24xx_get_driver_data(pdev);
1973 if (!ourport->drv_data) {
1974 dev_err(&pdev->dev, "could not find driver data\n");
1975 return -ENODEV;
1976 }
1977
1978 ourport->baudclk = ERR_PTR(-EINVAL);
1979 ourport->info = &ourport->drv_data->info;
1980 ourport->cfg = (dev_get_platdata(&pdev->dev)) ?
1981 dev_get_platdata(&pdev->dev) :
1982 &ourport->drv_data->def_cfg;
1983
1984 switch (ourport->info->type) {
1985 case TYPE_S3C6400:
1986 ourport->port.ops = &s3c64xx_serial_ops;
1987 break;
1988 case TYPE_APPLE_S5L:
1989 ourport->port.ops = &apple_s5l_serial_ops;
1990 break;
1991 }
1992
1993 ourport->port.iotype = ourport->info->iotype;
1994
1995 if (np) {
1996 fifosize_prop = of_property_read_u32(np, "samsung,uart-fifosize",
1997 &ourport->port.fifosize);
1998
1999 if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
2000 switch (prop) {
2001 case 1:
2002 ourport->port.iotype = UPIO_MEM;
2003 break;
2004 case 4:
2005 ourport->port.iotype = UPIO_MEM32;
2006 break;
2007 default:
2008 dev_warn(&pdev->dev, "unsupported reg-io-width (%d)\n",
2009 prop);
2010 return -EINVAL;
2011 }
2012 }
2013 }
2014
2015 if (fifosize_prop) {
2016 if (ourport->drv_data->fifosize[index])
2017 ourport->port.fifosize = ourport->drv_data->fifosize[index];
2018 else if (ourport->info->fifosize)
2019 ourport->port.fifosize = ourport->info->fifosize;
2020 }
2021
2022 ourport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SAMSUNG_CONSOLE);
2023
2024 /*
2025 * DMA transfers must be aligned at least to cache line size,
2026 * so find minimal transfer size suitable for DMA mode
2027 */
2028 ourport->min_dma_size = max_t(int, ourport->port.fifosize,
2029 dma_get_cache_alignment());
2030
2031 dev_dbg(&pdev->dev, "%s: initialising port %p...\n", __func__, ourport);
2032
2033 ret = s3c24xx_serial_init_port(ourport, pdev);
2034 if (ret < 0)
2035 return ret;
2036
2037 if (!s3c24xx_uart_drv.state) {
2038 ret = uart_register_driver(&s3c24xx_uart_drv);
2039 if (ret < 0) {
2040 pr_err("Failed to register Samsung UART driver\n");
2041 return ret;
2042 }
2043 }
2044
2045 dev_dbg(&pdev->dev, "%s: adding port\n", __func__);
2046 uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
2047 platform_set_drvdata(pdev, &ourport->port);
2048
2049 /*
2050 * Deactivate the clock enabled in s3c24xx_serial_init_port here,
2051 * so that a potential re-enablement through the pm-callback overlaps
2052 * and keeps the clock enabled in this case.
2053 */
2054 clk_disable_unprepare(ourport->clk);
2055 if (!IS_ERR(ourport->baudclk))
2056 clk_disable_unprepare(ourport->baudclk);
2057
2058 probe_index++;
2059
2060 return 0;
2061 }
2062
s3c24xx_serial_remove(struct platform_device * dev)2063 static void s3c24xx_serial_remove(struct platform_device *dev)
2064 {
2065 struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
2066
2067 if (port)
2068 uart_remove_one_port(&s3c24xx_uart_drv, port);
2069
2070 uart_unregister_driver(&s3c24xx_uart_drv);
2071 }
2072
2073 /* UART power management code */
2074 #ifdef CONFIG_PM_SLEEP
s3c24xx_serial_suspend(struct device * dev)2075 static int s3c24xx_serial_suspend(struct device *dev)
2076 {
2077 struct uart_port *port = s3c24xx_dev_to_port(dev);
2078
2079 if (port)
2080 uart_suspend_port(&s3c24xx_uart_drv, port);
2081
2082 return 0;
2083 }
2084
s3c24xx_serial_resume(struct device * dev)2085 static int s3c24xx_serial_resume(struct device *dev)
2086 {
2087 struct uart_port *port = s3c24xx_dev_to_port(dev);
2088 struct s3c24xx_uart_port *ourport = to_ourport(port);
2089
2090 if (port) {
2091 clk_prepare_enable(ourport->clk);
2092 if (!IS_ERR(ourport->baudclk))
2093 clk_prepare_enable(ourport->baudclk);
2094 s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
2095 if (!IS_ERR(ourport->baudclk))
2096 clk_disable_unprepare(ourport->baudclk);
2097 clk_disable_unprepare(ourport->clk);
2098
2099 uart_resume_port(&s3c24xx_uart_drv, port);
2100 }
2101
2102 return 0;
2103 }
2104
s3c24xx_serial_resume_noirq(struct device * dev)2105 static int s3c24xx_serial_resume_noirq(struct device *dev)
2106 {
2107 struct uart_port *port = s3c24xx_dev_to_port(dev);
2108 struct s3c24xx_uart_port *ourport = to_ourport(port);
2109
2110 if (port) {
2111 /* restore IRQ mask */
2112 switch (ourport->info->type) {
2113 case TYPE_S3C6400: {
2114 u32 uintm = 0xf;
2115
2116 if (ourport->tx_enabled)
2117 uintm &= ~S3C64XX_UINTM_TXD_MSK;
2118 if (ourport->rx_enabled)
2119 uintm &= ~S3C64XX_UINTM_RXD_MSK;
2120 clk_prepare_enable(ourport->clk);
2121 if (!IS_ERR(ourport->baudclk))
2122 clk_prepare_enable(ourport->baudclk);
2123 wr_regl(port, S3C64XX_UINTM, uintm);
2124 if (!IS_ERR(ourport->baudclk))
2125 clk_disable_unprepare(ourport->baudclk);
2126 clk_disable_unprepare(ourport->clk);
2127 break;
2128 }
2129 case TYPE_APPLE_S5L: {
2130 u32 ucon;
2131 int ret;
2132
2133 ret = clk_prepare_enable(ourport->clk);
2134 if (ret) {
2135 dev_err(dev, "clk_enable clk failed: %d\n", ret);
2136 return ret;
2137 }
2138 if (!IS_ERR(ourport->baudclk)) {
2139 ret = clk_prepare_enable(ourport->baudclk);
2140 if (ret) {
2141 dev_err(dev, "clk_enable baudclk failed: %d\n", ret);
2142 clk_disable_unprepare(ourport->clk);
2143 return ret;
2144 }
2145 }
2146
2147 ucon = rd_regl(port, S3C2410_UCON);
2148
2149 ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |
2150 APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
2151 APPLE_S5L_UCON_RXTO_ENA_MSK |
2152 APPLE_S5L_UCON_RXTO_LEGACY_ENA_MSK);
2153
2154 if (ourport->tx_enabled)
2155 ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK;
2156 if (ourport->rx_enabled)
2157 ucon |= APPLE_S5L_UCON_RXTHRESH_ENA_MSK |
2158 APPLE_S5L_UCON_RXTO_ENA_MSK |
2159 APPLE_S5L_UCON_RXTO_LEGACY_ENA_MSK;
2160
2161 wr_regl(port, S3C2410_UCON, ucon);
2162
2163 if (!IS_ERR(ourport->baudclk))
2164 clk_disable_unprepare(ourport->baudclk);
2165 clk_disable_unprepare(ourport->clk);
2166 break;
2167 }
2168 default:
2169 break;
2170 }
2171 }
2172
2173 return 0;
2174 }
2175
2176 static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
2177 SET_SYSTEM_SLEEP_PM_OPS(s3c24xx_serial_suspend, s3c24xx_serial_resume)
2178 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, s3c24xx_serial_resume_noirq)
2179 };
2180 #define SERIAL_SAMSUNG_PM_OPS (&s3c24xx_serial_pm_ops)
2181
2182 #else /* !CONFIG_PM_SLEEP */
2183
2184 #define SERIAL_SAMSUNG_PM_OPS NULL
2185 #endif /* CONFIG_PM_SLEEP */
2186
2187 /* Console code */
2188
2189 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
2190
2191 static struct uart_port *cons_uart;
2192
2193 static bool
s3c24xx_serial_console_txrdy(struct uart_port * port,u32 ufcon)2194 s3c24xx_serial_console_txrdy(struct uart_port *port, u32 ufcon)
2195 {
2196 const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
2197 u32 ufstat, utrstat;
2198
2199 if (ufcon & S3C2410_UFCON_FIFOMODE) {
2200 /* fifo mode - check amount of data in fifo registers... */
2201
2202 ufstat = rd_regl(port, S3C2410_UFSTAT);
2203 return !(ufstat & info->tx_fifofull);
2204 }
2205
2206 /* in non-fifo mode, we go and use the tx buffer empty */
2207
2208 utrstat = rd_regl(port, S3C2410_UTRSTAT);
2209 return utrstat & S3C2410_UTRSTAT_TXE;
2210 }
2211
2212 static bool
s3c24xx_port_configured(u32 ucon)2213 s3c24xx_port_configured(u32 ucon)
2214 {
2215 /* consider the serial port configured if the tx/rx mode set */
2216 return (ucon & 0xf) != 0;
2217 }
2218
2219 #ifdef CONFIG_CONSOLE_POLL
2220 /*
2221 * Console polling routines for writing and reading from the uart while
2222 * in an interrupt or debug context.
2223 */
2224
s3c24xx_serial_get_poll_char(struct uart_port * port)2225 static int s3c24xx_serial_get_poll_char(struct uart_port *port)
2226 {
2227 const struct s3c24xx_uart_port *ourport = to_ourport(port);
2228 u32 ufstat;
2229
2230 ufstat = rd_regl(port, S3C2410_UFSTAT);
2231 if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
2232 return NO_POLL_CHAR;
2233
2234 return rd_reg(port, S3C2410_URXH);
2235 }
2236
s3c24xx_serial_put_poll_char(struct uart_port * port,unsigned char c)2237 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
2238 unsigned char c)
2239 {
2240 u32 ufcon = rd_regl(port, S3C2410_UFCON);
2241 u32 ucon = rd_regl(port, S3C2410_UCON);
2242
2243 /* not possible to xmit on unconfigured port */
2244 if (!s3c24xx_port_configured(ucon))
2245 return;
2246
2247 while (!s3c24xx_serial_console_txrdy(port, ufcon))
2248 cpu_relax();
2249 wr_reg(port, S3C2410_UTXH, c);
2250 }
2251
2252 #endif /* CONFIG_CONSOLE_POLL */
2253
2254 static void
s3c24xx_serial_console_putchar(struct uart_port * port,unsigned char ch)2255 s3c24xx_serial_console_putchar(struct uart_port *port, unsigned char ch)
2256 {
2257 u32 ufcon = rd_regl(port, S3C2410_UFCON);
2258
2259 while (!s3c24xx_serial_console_txrdy(port, ufcon))
2260 cpu_relax();
2261 wr_reg(port, S3C2410_UTXH, ch);
2262 }
2263
2264 static void
s3c24xx_serial_console_write(struct console * co,const char * s,unsigned int count)2265 s3c24xx_serial_console_write(struct console *co, const char *s,
2266 unsigned int count)
2267 {
2268 u32 ucon = rd_regl(cons_uart, S3C2410_UCON);
2269 unsigned long flags;
2270 bool locked = true;
2271
2272 /* not possible to xmit on unconfigured port */
2273 if (!s3c24xx_port_configured(ucon))
2274 return;
2275
2276 if (cons_uart->sysrq)
2277 locked = false;
2278 else if (oops_in_progress)
2279 locked = uart_port_trylock_irqsave(cons_uart, &flags);
2280 else
2281 uart_port_lock_irqsave(cons_uart, &flags);
2282
2283 uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
2284
2285 if (locked)
2286 uart_port_unlock_irqrestore(cons_uart, flags);
2287 }
2288
2289 /* Shouldn't be __init, as it can be instantiated from other module */
2290 static void
s3c24xx_serial_get_options(struct uart_port * port,int * baud,int * parity,int * bits)2291 s3c24xx_serial_get_options(struct uart_port *port, int *baud,
2292 int *parity, int *bits)
2293 {
2294 struct clk *clk;
2295 unsigned long rate;
2296 u32 ulcon, ucon, ubrdiv;
2297 char clk_name[MAX_CLK_NAME_LENGTH];
2298 u8 clk_sel;
2299
2300 ulcon = rd_regl(port, S3C2410_ULCON);
2301 ucon = rd_regl(port, S3C2410_UCON);
2302 ubrdiv = rd_regl(port, S3C2410_UBRDIV);
2303
2304 if (s3c24xx_port_configured(ucon)) {
2305 switch (ulcon & S3C2410_LCON_CSMASK) {
2306 case S3C2410_LCON_CS5:
2307 *bits = 5;
2308 break;
2309 case S3C2410_LCON_CS6:
2310 *bits = 6;
2311 break;
2312 case S3C2410_LCON_CS7:
2313 *bits = 7;
2314 break;
2315 case S3C2410_LCON_CS8:
2316 default:
2317 *bits = 8;
2318 break;
2319 }
2320
2321 switch (ulcon & S3C2410_LCON_PMASK) {
2322 case S3C2410_LCON_PEVEN:
2323 *parity = 'e';
2324 break;
2325
2326 case S3C2410_LCON_PODD:
2327 *parity = 'o';
2328 break;
2329
2330 case S3C2410_LCON_PNONE:
2331 default:
2332 *parity = 'n';
2333 }
2334
2335 /* now calculate the baud rate */
2336
2337 clk_sel = s3c24xx_serial_getsource(port);
2338 sprintf(clk_name, "clk_uart_baud%d", clk_sel);
2339
2340 clk = clk_get(port->dev, clk_name);
2341 if (!IS_ERR(clk))
2342 rate = clk_get_rate(clk);
2343 else
2344 rate = 1;
2345
2346 *baud = rate / (16 * (ubrdiv + 1));
2347 dev_dbg(port->dev, "calculated baud %d\n", *baud);
2348 }
2349 }
2350
2351 /* Shouldn't be __init, as it can be instantiated from other module */
2352 static int
s3c24xx_serial_console_setup(struct console * co,char * options)2353 s3c24xx_serial_console_setup(struct console *co, char *options)
2354 {
2355 struct uart_port *port;
2356 int baud = 9600;
2357 int bits = 8;
2358 int parity = 'n';
2359 int flow = 'n';
2360
2361 /* is this a valid port */
2362
2363 if (co->index == -1 || co->index >= UART_NR)
2364 co->index = 0;
2365
2366 port = &s3c24xx_serial_ports[co->index].port;
2367
2368 /* is the port configured? */
2369
2370 if (port->mapbase == 0x0)
2371 return -ENODEV;
2372
2373 cons_uart = port;
2374
2375 /*
2376 * Check whether an invalid uart number has been specified, and
2377 * if so, search for the first available port that does have
2378 * console support.
2379 */
2380 if (options)
2381 uart_parse_options(options, &baud, &parity, &bits, &flow);
2382 else
2383 s3c24xx_serial_get_options(port, &baud, &parity, &bits);
2384
2385 dev_dbg(port->dev, "baud %d\n", baud);
2386
2387 return uart_set_options(port, co, baud, parity, bits, flow);
2388 }
2389
2390 static struct console s3c24xx_serial_console = {
2391 .name = S3C24XX_SERIAL_NAME,
2392 .device = uart_console_device,
2393 .flags = CON_PRINTBUFFER,
2394 .index = -1,
2395 .write = s3c24xx_serial_console_write,
2396 .setup = s3c24xx_serial_console_setup,
2397 .data = &s3c24xx_uart_drv,
2398 };
2399 #endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
2400
2401 #if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)
2402 static const struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {
2403 .info = {
2404 .name = "Samsung S3C6400 UART",
2405 .type = TYPE_S3C6400,
2406 .port_type = PORT_S3C6400,
2407 .iotype = UPIO_MEM,
2408 .fifosize = 64,
2409 .has_divslot = true,
2410 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
2411 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
2412 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
2413 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
2414 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
2415 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
2416 .def_clk_sel = S3C2410_UCON_CLKSEL2,
2417 .num_clks = 4,
2418 .clksel_mask = S3C6400_UCON_CLKMASK,
2419 .clksel_shift = S3C6400_UCON_CLKSHIFT,
2420 },
2421 .def_cfg = {
2422 .ucon = S3C2410_UCON_DEFAULT,
2423 .ufcon = S3C2410_UFCON_DEFAULT,
2424 },
2425 };
2426 #define S3C6400_SERIAL_DRV_DATA (&s3c6400_serial_drv_data)
2427 #else
2428 #define S3C6400_SERIAL_DRV_DATA NULL
2429 #endif
2430
2431 #ifdef CONFIG_CPU_S5PV210
2432 static const struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {
2433 .info = {
2434 .name = "Samsung S5PV210 UART",
2435 .type = TYPE_S3C6400,
2436 .port_type = PORT_S3C6400,
2437 .iotype = UPIO_MEM,
2438 .has_divslot = true,
2439 .rx_fifomask = S5PV210_UFSTAT_RXMASK,
2440 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT,
2441 .rx_fifofull = S5PV210_UFSTAT_RXFULL,
2442 .tx_fifofull = S5PV210_UFSTAT_TXFULL,
2443 .tx_fifomask = S5PV210_UFSTAT_TXMASK,
2444 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT,
2445 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2446 .num_clks = 2,
2447 .clksel_mask = S5PV210_UCON_CLKMASK,
2448 .clksel_shift = S5PV210_UCON_CLKSHIFT,
2449 },
2450 .def_cfg = {
2451 .ucon = S5PV210_UCON_DEFAULT,
2452 .ufcon = S5PV210_UFCON_DEFAULT,
2453 },
2454 .fifosize = { 256, 64, 16, 16 },
2455 };
2456 #define S5PV210_SERIAL_DRV_DATA (&s5pv210_serial_drv_data)
2457 #else
2458 #define S5PV210_SERIAL_DRV_DATA NULL
2459 #endif
2460
2461 #if defined(CONFIG_ARCH_EXYNOS)
2462 #define EXYNOS_COMMON_SERIAL_DRV_DATA \
2463 .info = { \
2464 .name = "Samsung Exynos UART", \
2465 .type = TYPE_S3C6400, \
2466 .port_type = PORT_S3C6400, \
2467 .iotype = UPIO_MEM, \
2468 .has_divslot = true, \
2469 .rx_fifomask = S5PV210_UFSTAT_RXMASK, \
2470 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT, \
2471 .rx_fifofull = S5PV210_UFSTAT_RXFULL, \
2472 .tx_fifofull = S5PV210_UFSTAT_TXFULL, \
2473 .tx_fifomask = S5PV210_UFSTAT_TXMASK, \
2474 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT, \
2475 .def_clk_sel = S3C2410_UCON_CLKSEL0, \
2476 .num_clks = 1, \
2477 .clksel_mask = 0, \
2478 .clksel_shift = 0, \
2479 }, \
2480 .def_cfg = { \
2481 .ucon = S5PV210_UCON_DEFAULT, \
2482 .ufcon = S5PV210_UFCON_DEFAULT, \
2483 .has_fracval = 1, \
2484 } \
2485
2486 static const struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {
2487 EXYNOS_COMMON_SERIAL_DRV_DATA,
2488 .fifosize = { 256, 64, 16, 16 },
2489 };
2490
2491 static const struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {
2492 EXYNOS_COMMON_SERIAL_DRV_DATA,
2493 .fifosize = { 64, 256, 16, 256 },
2494 };
2495
2496 static const struct s3c24xx_serial_drv_data exynos850_serial_drv_data = {
2497 EXYNOS_COMMON_SERIAL_DRV_DATA,
2498 .fifosize = { 256, 64, 64, 64 },
2499 };
2500
2501 static const struct s3c24xx_serial_drv_data exynos8895_serial_drv_data = {
2502 EXYNOS_COMMON_SERIAL_DRV_DATA,
2503 /* samsung,uart-fifosize must be specified in the device tree. */
2504 .fifosize = { 0 },
2505 };
2506
2507 static const struct s3c24xx_serial_drv_data gs101_serial_drv_data = {
2508 .info = {
2509 .name = "Google GS101 UART",
2510 .type = TYPE_S3C6400,
2511 .port_type = PORT_S3C6400,
2512 .iotype = UPIO_MEM32,
2513 .has_divslot = true,
2514 .rx_fifomask = S5PV210_UFSTAT_RXMASK,
2515 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT,
2516 .rx_fifofull = S5PV210_UFSTAT_RXFULL,
2517 .tx_fifofull = S5PV210_UFSTAT_TXFULL,
2518 .tx_fifomask = S5PV210_UFSTAT_TXMASK,
2519 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT,
2520 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2521 .num_clks = 1,
2522 .clksel_mask = 0,
2523 .clksel_shift = 0,
2524 },
2525 .def_cfg = {
2526 .ucon = S5PV210_UCON_DEFAULT,
2527 .ufcon = S5PV210_UFCON_DEFAULT,
2528 .has_fracval = 1,
2529 },
2530 /* samsung,uart-fifosize must be specified in the device tree. */
2531 .fifosize = { 0 },
2532 };
2533
2534 #define EXYNOS4210_SERIAL_DRV_DATA (&exynos4210_serial_drv_data)
2535 #define EXYNOS5433_SERIAL_DRV_DATA (&exynos5433_serial_drv_data)
2536 #define EXYNOS850_SERIAL_DRV_DATA (&exynos850_serial_drv_data)
2537 #define EXYNOS8895_SERIAL_DRV_DATA (&exynos8895_serial_drv_data)
2538 #define GS101_SERIAL_DRV_DATA (&gs101_serial_drv_data)
2539
2540 #else
2541 #define EXYNOS4210_SERIAL_DRV_DATA NULL
2542 #define EXYNOS5433_SERIAL_DRV_DATA NULL
2543 #define EXYNOS850_SERIAL_DRV_DATA NULL
2544 #define EXYNOS8895_SERIAL_DRV_DATA NULL
2545 #define GS101_SERIAL_DRV_DATA NULL
2546 #endif
2547
2548 #ifdef CONFIG_ARCH_APPLE
2549 static const struct s3c24xx_serial_drv_data s5l_serial_drv_data = {
2550 .info = {
2551 .name = "Apple S5L UART",
2552 .type = TYPE_APPLE_S5L,
2553 .port_type = PORT_8250,
2554 .iotype = UPIO_MEM32,
2555 .fifosize = 16,
2556 .rx_fifomask = S3C2410_UFSTAT_RXMASK,
2557 .rx_fifoshift = S3C2410_UFSTAT_RXSHIFT,
2558 .rx_fifofull = S3C2410_UFSTAT_RXFULL,
2559 .tx_fifofull = S3C2410_UFSTAT_TXFULL,
2560 .tx_fifomask = S3C2410_UFSTAT_TXMASK,
2561 .tx_fifoshift = S3C2410_UFSTAT_TXSHIFT,
2562 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2563 .num_clks = 1,
2564 .clksel_mask = 0,
2565 .clksel_shift = 0,
2566 .ucon_mask = APPLE_S5L_UCON_MASK,
2567 },
2568 .def_cfg = {
2569 .ucon = APPLE_S5L_UCON_DEFAULT,
2570 .ufcon = S3C2410_UFCON_DEFAULT,
2571 },
2572 };
2573 #define S5L_SERIAL_DRV_DATA (&s5l_serial_drv_data)
2574 #else
2575 #define S5L_SERIAL_DRV_DATA NULL
2576 #endif
2577
2578 #if defined(CONFIG_ARCH_ARTPEC)
2579 static const struct s3c24xx_serial_drv_data artpec8_serial_drv_data = {
2580 .info = {
2581 .name = "Axis ARTPEC-8 UART",
2582 .type = TYPE_S3C6400,
2583 .port_type = PORT_S3C6400,
2584 .iotype = UPIO_MEM,
2585 .fifosize = 64,
2586 .has_divslot = true,
2587 .rx_fifomask = S5PV210_UFSTAT_RXMASK,
2588 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT,
2589 .rx_fifofull = S5PV210_UFSTAT_RXFULL,
2590 .tx_fifofull = S5PV210_UFSTAT_TXFULL,
2591 .tx_fifomask = S5PV210_UFSTAT_TXMASK,
2592 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT,
2593 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2594 .num_clks = 1,
2595 .clksel_mask = 0,
2596 .clksel_shift = 0,
2597 },
2598 .def_cfg = {
2599 .ucon = S5PV210_UCON_DEFAULT,
2600 .ufcon = S5PV210_UFCON_DEFAULT,
2601 .has_fracval = 1,
2602 }
2603 };
2604 #define ARTPEC8_SERIAL_DRV_DATA (&artpec8_serial_drv_data)
2605 #else
2606 #define ARTPEC8_SERIAL_DRV_DATA (NULL)
2607 #endif
2608
2609 static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
2610 {
2611 .name = "s3c6400-uart",
2612 .driver_data = (kernel_ulong_t)S3C6400_SERIAL_DRV_DATA,
2613 }, {
2614 .name = "s5pv210-uart",
2615 .driver_data = (kernel_ulong_t)S5PV210_SERIAL_DRV_DATA,
2616 }, {
2617 .name = "exynos4210-uart",
2618 .driver_data = (kernel_ulong_t)EXYNOS4210_SERIAL_DRV_DATA,
2619 }, {
2620 .name = "exynos5433-uart",
2621 .driver_data = (kernel_ulong_t)EXYNOS5433_SERIAL_DRV_DATA,
2622 }, {
2623 .name = "s5l-uart",
2624 .driver_data = (kernel_ulong_t)S5L_SERIAL_DRV_DATA,
2625 }, {
2626 .name = "exynos850-uart",
2627 .driver_data = (kernel_ulong_t)EXYNOS850_SERIAL_DRV_DATA,
2628 }, {
2629 .name = "artpec8-uart",
2630 .driver_data = (kernel_ulong_t)ARTPEC8_SERIAL_DRV_DATA,
2631 }, {
2632 .name = "gs101-uart",
2633 .driver_data = (kernel_ulong_t)GS101_SERIAL_DRV_DATA,
2634 }, {
2635 .name = "exynos8895-uart",
2636 .driver_data = (kernel_ulong_t)EXYNOS8895_SERIAL_DRV_DATA,
2637 },
2638 { },
2639 };
2640 MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);
2641
2642 #ifdef CONFIG_OF
2643 static const struct of_device_id s3c24xx_uart_dt_match[] = {
2644 { .compatible = "samsung,s3c6400-uart",
2645 .data = S3C6400_SERIAL_DRV_DATA },
2646 { .compatible = "samsung,s5pv210-uart",
2647 .data = S5PV210_SERIAL_DRV_DATA },
2648 { .compatible = "samsung,exynos4210-uart",
2649 .data = EXYNOS4210_SERIAL_DRV_DATA },
2650 { .compatible = "samsung,exynos5433-uart",
2651 .data = EXYNOS5433_SERIAL_DRV_DATA },
2652 { .compatible = "apple,s5l-uart",
2653 .data = S5L_SERIAL_DRV_DATA },
2654 { .compatible = "samsung,exynos850-uart",
2655 .data = EXYNOS850_SERIAL_DRV_DATA },
2656 { .compatible = "axis,artpec8-uart",
2657 .data = ARTPEC8_SERIAL_DRV_DATA },
2658 { .compatible = "google,gs101-uart",
2659 .data = GS101_SERIAL_DRV_DATA },
2660 { .compatible = "samsung,exynos8895-uart",
2661 .data = EXYNOS8895_SERIAL_DRV_DATA },
2662 {},
2663 };
2664 MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
2665 #endif
2666
2667 static struct platform_driver samsung_serial_driver = {
2668 .probe = s3c24xx_serial_probe,
2669 .remove = s3c24xx_serial_remove,
2670 .id_table = s3c24xx_serial_driver_ids,
2671 .driver = {
2672 .name = "samsung-uart",
2673 .pm = SERIAL_SAMSUNG_PM_OPS,
2674 .of_match_table = of_match_ptr(s3c24xx_uart_dt_match),
2675 },
2676 };
2677
samsung_serial_init(void)2678 static int __init samsung_serial_init(void)
2679 {
2680 int ret;
2681
2682 s3c24xx_serial_register_console();
2683
2684 ret = platform_driver_register(&samsung_serial_driver);
2685 if (ret) {
2686 s3c24xx_serial_unregister_console();
2687 return ret;
2688 }
2689
2690 return 0;
2691 }
2692
samsung_serial_exit(void)2693 static void __exit samsung_serial_exit(void)
2694 {
2695 platform_driver_unregister(&samsung_serial_driver);
2696 s3c24xx_serial_unregister_console();
2697 }
2698
2699 module_init(samsung_serial_init);
2700 module_exit(samsung_serial_exit);
2701
2702 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
2703 /*
2704 * Early console.
2705 */
2706
wr_reg_barrier(const struct uart_port * port,u32 reg,u32 val)2707 static void wr_reg_barrier(const struct uart_port *port, u32 reg, u32 val)
2708 {
2709 switch (port->iotype) {
2710 case UPIO_MEM:
2711 writeb(val, portaddr(port, reg));
2712 break;
2713 case UPIO_MEM32:
2714 writel(val, portaddr(port, reg));
2715 break;
2716 }
2717 }
2718
2719 struct samsung_early_console_data {
2720 u32 txfull_mask;
2721 u32 rxfifo_mask;
2722 };
2723
samsung_early_busyuart(const struct uart_port * port)2724 static void samsung_early_busyuart(const struct uart_port *port)
2725 {
2726 while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))
2727 ;
2728 }
2729
samsung_early_busyuart_fifo(const struct uart_port * port)2730 static void samsung_early_busyuart_fifo(const struct uart_port *port)
2731 {
2732 const struct samsung_early_console_data *data = port->private_data;
2733
2734 while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)
2735 ;
2736 }
2737
samsung_early_putc(struct uart_port * port,unsigned char c)2738 static void samsung_early_putc(struct uart_port *port, unsigned char c)
2739 {
2740 if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
2741 samsung_early_busyuart_fifo(port);
2742 else
2743 samsung_early_busyuart(port);
2744
2745 wr_reg_barrier(port, S3C2410_UTXH, c);
2746 }
2747
samsung_early_write(struct console * con,const char * s,unsigned int n)2748 static void samsung_early_write(struct console *con, const char *s,
2749 unsigned int n)
2750 {
2751 struct earlycon_device *dev = con->data;
2752
2753 uart_console_write(&dev->port, s, n, samsung_early_putc);
2754 }
2755
samsung_early_read(struct console * con,char * s,unsigned int n)2756 static int samsung_early_read(struct console *con, char *s, unsigned int n)
2757 {
2758 struct earlycon_device *dev = con->data;
2759 const struct samsung_early_console_data *data = dev->port.private_data;
2760 int num_read = 0;
2761 u32 ch, ufstat;
2762
2763 while (num_read < n) {
2764 ufstat = rd_regl(&dev->port, S3C2410_UFSTAT);
2765 if (!(ufstat & data->rxfifo_mask))
2766 break;
2767 ch = rd_reg(&dev->port, S3C2410_URXH);
2768 if (ch == NO_POLL_CHAR)
2769 break;
2770
2771 s[num_read++] = ch;
2772 }
2773
2774 return num_read;
2775 }
2776
samsung_early_console_setup(struct earlycon_device * device,const char * opt)2777 static int __init samsung_early_console_setup(struct earlycon_device *device,
2778 const char *opt)
2779 {
2780 if (!device->port.membase)
2781 return -ENODEV;
2782
2783 device->con->write = samsung_early_write;
2784 device->con->read = samsung_early_read;
2785 return 0;
2786 }
2787
2788 /* S3C2410 */
2789 static struct samsung_early_console_data s3c2410_early_console_data = {
2790 .txfull_mask = S3C2410_UFSTAT_TXFULL,
2791 .rxfifo_mask = S3C2410_UFSTAT_RXFULL | S3C2410_UFSTAT_RXMASK,
2792 };
2793
2794 /* S3C64xx */
2795 static struct samsung_early_console_data s3c2440_early_console_data = {
2796 .txfull_mask = S3C2440_UFSTAT_TXFULL,
2797 .rxfifo_mask = S3C2440_UFSTAT_RXFULL | S3C2440_UFSTAT_RXMASK,
2798 };
2799
s3c2440_early_console_setup(struct earlycon_device * device,const char * opt)2800 static int __init s3c2440_early_console_setup(struct earlycon_device *device,
2801 const char *opt)
2802 {
2803 device->port.private_data = &s3c2440_early_console_data;
2804 return samsung_early_console_setup(device, opt);
2805 }
2806
2807 OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",
2808 s3c2440_early_console_setup);
2809
2810 /* S5PV210, Exynos */
2811 static struct samsung_early_console_data s5pv210_early_console_data = {
2812 .txfull_mask = S5PV210_UFSTAT_TXFULL,
2813 .rxfifo_mask = S5PV210_UFSTAT_RXFULL | S5PV210_UFSTAT_RXMASK,
2814 };
2815
s5pv210_early_console_setup(struct earlycon_device * device,const char * opt)2816 static int __init s5pv210_early_console_setup(struct earlycon_device *device,
2817 const char *opt)
2818 {
2819 device->port.private_data = &s5pv210_early_console_data;
2820 return samsung_early_console_setup(device, opt);
2821 }
2822
2823 OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
2824 s5pv210_early_console_setup);
2825 OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
2826 s5pv210_early_console_setup);
2827 OF_EARLYCON_DECLARE(artpec8, "axis,artpec8-uart",
2828 s5pv210_early_console_setup);
2829
gs101_early_console_setup(struct earlycon_device * device,const char * opt)2830 static int __init gs101_early_console_setup(struct earlycon_device *device,
2831 const char *opt)
2832 {
2833 /* gs101 always expects MMIO32 register accesses. */
2834 device->port.iotype = UPIO_MEM32;
2835
2836 return s5pv210_early_console_setup(device, opt);
2837 }
2838
2839 OF_EARLYCON_DECLARE(gs101, "google,gs101-uart", gs101_early_console_setup);
2840
2841 /* Apple S5L */
apple_s5l_early_console_setup(struct earlycon_device * device,const char * opt)2842 static int __init apple_s5l_early_console_setup(struct earlycon_device *device,
2843 const char *opt)
2844 {
2845 /* Apple A7-A11 requires MMIO32 register accesses. */
2846 device->port.iotype = UPIO_MEM32;
2847
2848 /* Close enough to S3C2410 for earlycon... */
2849 device->port.private_data = &s3c2410_early_console_data;
2850
2851 #ifdef CONFIG_ARM64
2852 /* ... but we need to override the existing fixmap entry as nGnRnE */
2853 __set_fixmap(FIX_EARLYCON_MEM_BASE, device->port.mapbase,
2854 __pgprot(PROT_DEVICE_nGnRnE));
2855 #endif
2856 return samsung_early_console_setup(device, opt);
2857 }
2858
2859 OF_EARLYCON_DECLARE(s5l, "apple,s5l-uart", apple_s5l_early_console_setup);
2860 #endif
2861
2862 MODULE_ALIAS("platform:samsung-uart");
2863 MODULE_DESCRIPTION("Samsung SoC Serial port driver");
2864 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
2865 MODULE_LICENSE("GPL v2");
2866