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mtd: nand: atmel: Relax tADL_min constraint
[mirror_ubuntu-artful-kernel.git] / drivers / tty / serial / fsl_lpuart.c
1 /*
2 * Freescale lpuart serial port driver
3 *
4 * Copyright 2012-2014 Freescale Semiconductor, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 */
11
12 #if defined(CONFIG_SERIAL_FSL_LPUART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
13 #define SUPPORT_SYSRQ
14 #endif
15
16 #include <linux/clk.h>
17 #include <linux/console.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/dmaengine.h>
20 #include <linux/dmapool.h>
21 #include <linux/io.h>
22 #include <linux/irq.h>
23 #include <linux/module.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/of_dma.h>
27 #include <linux/serial_core.h>
28 #include <linux/slab.h>
29 #include <linux/tty_flip.h>
30
31 /* All registers are 8-bit width */
32 #define UARTBDH 0x00
33 #define UARTBDL 0x01
34 #define UARTCR1 0x02
35 #define UARTCR2 0x03
36 #define UARTSR1 0x04
37 #define UARTCR3 0x06
38 #define UARTDR 0x07
39 #define UARTCR4 0x0a
40 #define UARTCR5 0x0b
41 #define UARTMODEM 0x0d
42 #define UARTPFIFO 0x10
43 #define UARTCFIFO 0x11
44 #define UARTSFIFO 0x12
45 #define UARTTWFIFO 0x13
46 #define UARTTCFIFO 0x14
47 #define UARTRWFIFO 0x15
48
49 #define UARTBDH_LBKDIE 0x80
50 #define UARTBDH_RXEDGIE 0x40
51 #define UARTBDH_SBR_MASK 0x1f
52
53 #define UARTCR1_LOOPS 0x80
54 #define UARTCR1_RSRC 0x20
55 #define UARTCR1_M 0x10
56 #define UARTCR1_WAKE 0x08
57 #define UARTCR1_ILT 0x04
58 #define UARTCR1_PE 0x02
59 #define UARTCR1_PT 0x01
60
61 #define UARTCR2_TIE 0x80
62 #define UARTCR2_TCIE 0x40
63 #define UARTCR2_RIE 0x20
64 #define UARTCR2_ILIE 0x10
65 #define UARTCR2_TE 0x08
66 #define UARTCR2_RE 0x04
67 #define UARTCR2_RWU 0x02
68 #define UARTCR2_SBK 0x01
69
70 #define UARTSR1_TDRE 0x80
71 #define UARTSR1_TC 0x40
72 #define UARTSR1_RDRF 0x20
73 #define UARTSR1_IDLE 0x10
74 #define UARTSR1_OR 0x08
75 #define UARTSR1_NF 0x04
76 #define UARTSR1_FE 0x02
77 #define UARTSR1_PE 0x01
78
79 #define UARTCR3_R8 0x80
80 #define UARTCR3_T8 0x40
81 #define UARTCR3_TXDIR 0x20
82 #define UARTCR3_TXINV 0x10
83 #define UARTCR3_ORIE 0x08
84 #define UARTCR3_NEIE 0x04
85 #define UARTCR3_FEIE 0x02
86 #define UARTCR3_PEIE 0x01
87
88 #define UARTCR4_MAEN1 0x80
89 #define UARTCR4_MAEN2 0x40
90 #define UARTCR4_M10 0x20
91 #define UARTCR4_BRFA_MASK 0x1f
92 #define UARTCR4_BRFA_OFF 0
93
94 #define UARTCR5_TDMAS 0x80
95 #define UARTCR5_RDMAS 0x20
96
97 #define UARTMODEM_RXRTSE 0x08
98 #define UARTMODEM_TXRTSPOL 0x04
99 #define UARTMODEM_TXRTSE 0x02
100 #define UARTMODEM_TXCTSE 0x01
101
102 #define UARTPFIFO_TXFE 0x80
103 #define UARTPFIFO_FIFOSIZE_MASK 0x7
104 #define UARTPFIFO_TXSIZE_OFF 4
105 #define UARTPFIFO_RXFE 0x08
106 #define UARTPFIFO_RXSIZE_OFF 0
107
108 #define UARTCFIFO_TXFLUSH 0x80
109 #define UARTCFIFO_RXFLUSH 0x40
110 #define UARTCFIFO_RXOFE 0x04
111 #define UARTCFIFO_TXOFE 0x02
112 #define UARTCFIFO_RXUFE 0x01
113
114 #define UARTSFIFO_TXEMPT 0x80
115 #define UARTSFIFO_RXEMPT 0x40
116 #define UARTSFIFO_RXOF 0x04
117 #define UARTSFIFO_TXOF 0x02
118 #define UARTSFIFO_RXUF 0x01
119
120 /* 32-bit register defination */
121 #define UARTBAUD 0x00
122 #define UARTSTAT 0x04
123 #define UARTCTRL 0x08
124 #define UARTDATA 0x0C
125 #define UARTMATCH 0x10
126 #define UARTMODIR 0x14
127 #define UARTFIFO 0x18
128 #define UARTWATER 0x1c
129
130 #define UARTBAUD_MAEN1 0x80000000
131 #define UARTBAUD_MAEN2 0x40000000
132 #define UARTBAUD_M10 0x20000000
133 #define UARTBAUD_TDMAE 0x00800000
134 #define UARTBAUD_RDMAE 0x00200000
135 #define UARTBAUD_MATCFG 0x00400000
136 #define UARTBAUD_BOTHEDGE 0x00020000
137 #define UARTBAUD_RESYNCDIS 0x00010000
138 #define UARTBAUD_LBKDIE 0x00008000
139 #define UARTBAUD_RXEDGIE 0x00004000
140 #define UARTBAUD_SBNS 0x00002000
141 #define UARTBAUD_SBR 0x00000000
142 #define UARTBAUD_SBR_MASK 0x1fff
143 #define UARTBAUD_OSR_MASK 0x1f
144 #define UARTBAUD_OSR_SHIFT 24
145
146 #define UARTSTAT_LBKDIF 0x80000000
147 #define UARTSTAT_RXEDGIF 0x40000000
148 #define UARTSTAT_MSBF 0x20000000
149 #define UARTSTAT_RXINV 0x10000000
150 #define UARTSTAT_RWUID 0x08000000
151 #define UARTSTAT_BRK13 0x04000000
152 #define UARTSTAT_LBKDE 0x02000000
153 #define UARTSTAT_RAF 0x01000000
154 #define UARTSTAT_TDRE 0x00800000
155 #define UARTSTAT_TC 0x00400000
156 #define UARTSTAT_RDRF 0x00200000
157 #define UARTSTAT_IDLE 0x00100000
158 #define UARTSTAT_OR 0x00080000
159 #define UARTSTAT_NF 0x00040000
160 #define UARTSTAT_FE 0x00020000
161 #define UARTSTAT_PE 0x00010000
162 #define UARTSTAT_MA1F 0x00008000
163 #define UARTSTAT_M21F 0x00004000
164
165 #define UARTCTRL_R8T9 0x80000000
166 #define UARTCTRL_R9T8 0x40000000
167 #define UARTCTRL_TXDIR 0x20000000
168 #define UARTCTRL_TXINV 0x10000000
169 #define UARTCTRL_ORIE 0x08000000
170 #define UARTCTRL_NEIE 0x04000000
171 #define UARTCTRL_FEIE 0x02000000
172 #define UARTCTRL_PEIE 0x01000000
173 #define UARTCTRL_TIE 0x00800000
174 #define UARTCTRL_TCIE 0x00400000
175 #define UARTCTRL_RIE 0x00200000
176 #define UARTCTRL_ILIE 0x00100000
177 #define UARTCTRL_TE 0x00080000
178 #define UARTCTRL_RE 0x00040000
179 #define UARTCTRL_RWU 0x00020000
180 #define UARTCTRL_SBK 0x00010000
181 #define UARTCTRL_MA1IE 0x00008000
182 #define UARTCTRL_MA2IE 0x00004000
183 #define UARTCTRL_IDLECFG 0x00000100
184 #define UARTCTRL_LOOPS 0x00000080
185 #define UARTCTRL_DOZEEN 0x00000040
186 #define UARTCTRL_RSRC 0x00000020
187 #define UARTCTRL_M 0x00000010
188 #define UARTCTRL_WAKE 0x00000008
189 #define UARTCTRL_ILT 0x00000004
190 #define UARTCTRL_PE 0x00000002
191 #define UARTCTRL_PT 0x00000001
192
193 #define UARTDATA_NOISY 0x00008000
194 #define UARTDATA_PARITYE 0x00004000
195 #define UARTDATA_FRETSC 0x00002000
196 #define UARTDATA_RXEMPT 0x00001000
197 #define UARTDATA_IDLINE 0x00000800
198 #define UARTDATA_MASK 0x3ff
199
200 #define UARTMODIR_IREN 0x00020000
201 #define UARTMODIR_TXCTSSRC 0x00000020
202 #define UARTMODIR_TXCTSC 0x00000010
203 #define UARTMODIR_RXRTSE 0x00000008
204 #define UARTMODIR_TXRTSPOL 0x00000004
205 #define UARTMODIR_TXRTSE 0x00000002
206 #define UARTMODIR_TXCTSE 0x00000001
207
208 #define UARTFIFO_TXEMPT 0x00800000
209 #define UARTFIFO_RXEMPT 0x00400000
210 #define UARTFIFO_TXOF 0x00020000
211 #define UARTFIFO_RXUF 0x00010000
212 #define UARTFIFO_TXFLUSH 0x00008000
213 #define UARTFIFO_RXFLUSH 0x00004000
214 #define UARTFIFO_TXOFE 0x00000200
215 #define UARTFIFO_RXUFE 0x00000100
216 #define UARTFIFO_TXFE 0x00000080
217 #define UARTFIFO_FIFOSIZE_MASK 0x7
218 #define UARTFIFO_TXSIZE_OFF 4
219 #define UARTFIFO_RXFE 0x00000008
220 #define UARTFIFO_RXSIZE_OFF 0
221
222 #define UARTWATER_COUNT_MASK 0xff
223 #define UARTWATER_TXCNT_OFF 8
224 #define UARTWATER_RXCNT_OFF 24
225 #define UARTWATER_WATER_MASK 0xff
226 #define UARTWATER_TXWATER_OFF 0
227 #define UARTWATER_RXWATER_OFF 16
228
229 /* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */
230 #define DMA_RX_TIMEOUT (10)
231
232 #define DRIVER_NAME "fsl-lpuart"
233 #define DEV_NAME "ttyLP"
234 #define UART_NR 6
235
236 /* IMX lpuart has four extra unused regs located at the beginning */
237 #define IMX_REG_OFF 0x10
238
239 struct lpuart_port {
240 struct uart_port port;
241 struct clk *clk;
242 unsigned int txfifo_size;
243 unsigned int rxfifo_size;
244
245 bool lpuart_dma_tx_use;
246 bool lpuart_dma_rx_use;
247 struct dma_chan *dma_tx_chan;
248 struct dma_chan *dma_rx_chan;
249 struct dma_async_tx_descriptor *dma_tx_desc;
250 struct dma_async_tx_descriptor *dma_rx_desc;
251 dma_cookie_t dma_tx_cookie;
252 dma_cookie_t dma_rx_cookie;
253 unsigned int dma_tx_bytes;
254 unsigned int dma_rx_bytes;
255 bool dma_tx_in_progress;
256 unsigned int dma_rx_timeout;
257 struct timer_list lpuart_timer;
258 struct scatterlist rx_sgl, tx_sgl[2];
259 struct circ_buf rx_ring;
260 int rx_dma_rng_buf_len;
261 unsigned int dma_tx_nents;
262 wait_queue_head_t dma_wait;
263 };
264
265 struct lpuart_soc_data {
266 char iotype;
267 u8 reg_off;
268 };
269
270 static const struct lpuart_soc_data vf_data = {
271 .iotype = UPIO_MEM,
272 };
273
274 static const struct lpuart_soc_data ls_data = {
275 .iotype = UPIO_MEM32BE,
276 };
277
278 static struct lpuart_soc_data imx_data = {
279 .iotype = UPIO_MEM32,
280 .reg_off = IMX_REG_OFF,
281 };
282
283 static const struct of_device_id lpuart_dt_ids[] = {
284 { .compatible = "fsl,vf610-lpuart", .data = &vf_data, },
285 { .compatible = "fsl,ls1021a-lpuart", .data = &ls_data, },
286 { .compatible = "fsl,imx7ulp-lpuart", .data = &imx_data, },
287 { /* sentinel */ }
288 };
289 MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
290
291 /* Forward declare this for the dma callbacks*/
292 static void lpuart_dma_tx_complete(void *arg);
293
294 static inline u32 lpuart32_read(struct uart_port *port, u32 off)
295 {
296 switch (port->iotype) {
297 case UPIO_MEM32:
298 return readl(port->membase + off);
299 case UPIO_MEM32BE:
300 return ioread32be(port->membase + off);
301 default:
302 return 0;
303 }
304 }
305
306 static inline void lpuart32_write(struct uart_port *port, u32 val,
307 u32 off)
308 {
309 switch (port->iotype) {
310 case UPIO_MEM32:
311 writel(val, port->membase + off);
312 break;
313 case UPIO_MEM32BE:
314 iowrite32be(val, port->membase + off);
315 break;
316 }
317 }
318
319 static void lpuart_stop_tx(struct uart_port *port)
320 {
321 unsigned char temp;
322
323 temp = readb(port->membase + UARTCR2);
324 temp &= ~(UARTCR2_TIE | UARTCR2_TCIE);
325 writeb(temp, port->membase + UARTCR2);
326 }
327
328 static void lpuart32_stop_tx(struct uart_port *port)
329 {
330 unsigned long temp;
331
332 temp = lpuart32_read(port, UARTCTRL);
333 temp &= ~(UARTCTRL_TIE | UARTCTRL_TCIE);
334 lpuart32_write(port, temp, UARTCTRL);
335 }
336
337 static void lpuart_stop_rx(struct uart_port *port)
338 {
339 unsigned char temp;
340
341 temp = readb(port->membase + UARTCR2);
342 writeb(temp & ~UARTCR2_RE, port->membase + UARTCR2);
343 }
344
345 static void lpuart32_stop_rx(struct uart_port *port)
346 {
347 unsigned long temp;
348
349 temp = lpuart32_read(port, UARTCTRL);
350 lpuart32_write(port, temp & ~UARTCTRL_RE, UARTCTRL);
351 }
352
353 static void lpuart_dma_tx(struct lpuart_port *sport)
354 {
355 struct circ_buf *xmit = &sport->port.state->xmit;
356 struct scatterlist *sgl = sport->tx_sgl;
357 struct device *dev = sport->port.dev;
358 int ret;
359
360 if (sport->dma_tx_in_progress)
361 return;
362
363 sport->dma_tx_bytes = uart_circ_chars_pending(xmit);
364
365 if (xmit->tail < xmit->head || xmit->head == 0) {
366 sport->dma_tx_nents = 1;
367 sg_init_one(sgl, xmit->buf + xmit->tail, sport->dma_tx_bytes);
368 } else {
369 sport->dma_tx_nents = 2;
370 sg_init_table(sgl, 2);
371 sg_set_buf(sgl, xmit->buf + xmit->tail,
372 UART_XMIT_SIZE - xmit->tail);
373 sg_set_buf(sgl + 1, xmit->buf, xmit->head);
374 }
375
376 ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
377 if (!ret) {
378 dev_err(dev, "DMA mapping error for TX.\n");
379 return;
380 }
381
382 sport->dma_tx_desc = dmaengine_prep_slave_sg(sport->dma_tx_chan, sgl,
383 sport->dma_tx_nents,
384 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
385 if (!sport->dma_tx_desc) {
386 dma_unmap_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
387 dev_err(dev, "Cannot prepare TX slave DMA!\n");
388 return;
389 }
390
391 sport->dma_tx_desc->callback = lpuart_dma_tx_complete;
392 sport->dma_tx_desc->callback_param = sport;
393 sport->dma_tx_in_progress = true;
394 sport->dma_tx_cookie = dmaengine_submit(sport->dma_tx_desc);
395 dma_async_issue_pending(sport->dma_tx_chan);
396 }
397
398 static void lpuart_dma_tx_complete(void *arg)
399 {
400 struct lpuart_port *sport = arg;
401 struct scatterlist *sgl = &sport->tx_sgl[0];
402 struct circ_buf *xmit = &sport->port.state->xmit;
403 unsigned long flags;
404
405 spin_lock_irqsave(&sport->port.lock, flags);
406
407 dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
408
409 xmit->tail = (xmit->tail + sport->dma_tx_bytes) & (UART_XMIT_SIZE - 1);
410
411 sport->port.icount.tx += sport->dma_tx_bytes;
412 sport->dma_tx_in_progress = false;
413 spin_unlock_irqrestore(&sport->port.lock, flags);
414
415 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
416 uart_write_wakeup(&sport->port);
417
418 if (waitqueue_active(&sport->dma_wait)) {
419 wake_up(&sport->dma_wait);
420 return;
421 }
422
423 spin_lock_irqsave(&sport->port.lock, flags);
424
425 if (!uart_circ_empty(xmit) && !uart_tx_stopped(&sport->port))
426 lpuart_dma_tx(sport);
427
428 spin_unlock_irqrestore(&sport->port.lock, flags);
429 }
430
431 static int lpuart_dma_tx_request(struct uart_port *port)
432 {
433 struct lpuart_port *sport = container_of(port,
434 struct lpuart_port, port);
435 struct dma_slave_config dma_tx_sconfig = {};
436 int ret;
437
438 dma_tx_sconfig.dst_addr = sport->port.mapbase + UARTDR;
439 dma_tx_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
440 dma_tx_sconfig.dst_maxburst = 1;
441 dma_tx_sconfig.direction = DMA_MEM_TO_DEV;
442 ret = dmaengine_slave_config(sport->dma_tx_chan, &dma_tx_sconfig);
443
444 if (ret) {
445 dev_err(sport->port.dev,
446 "DMA slave config failed, err = %d\n", ret);
447 return ret;
448 }
449
450 return 0;
451 }
452
453 static void lpuart_flush_buffer(struct uart_port *port)
454 {
455 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
456
457 if (sport->lpuart_dma_tx_use) {
458 if (sport->dma_tx_in_progress) {
459 dma_unmap_sg(sport->port.dev, &sport->tx_sgl[0],
460 sport->dma_tx_nents, DMA_TO_DEVICE);
461 sport->dma_tx_in_progress = false;
462 }
463 dmaengine_terminate_all(sport->dma_tx_chan);
464 }
465 }
466
467 #if defined(CONFIG_CONSOLE_POLL)
468
469 static int lpuart_poll_init(struct uart_port *port)
470 {
471 struct lpuart_port *sport = container_of(port,
472 struct lpuart_port, port);
473 unsigned long flags;
474 unsigned char temp;
475
476 sport->port.fifosize = 0;
477
478 spin_lock_irqsave(&sport->port.lock, flags);
479 /* Disable Rx & Tx */
480 writeb(0, sport->port.membase + UARTCR2);
481
482 temp = readb(sport->port.membase + UARTPFIFO);
483 /* Enable Rx and Tx FIFO */
484 writeb(temp | UARTPFIFO_RXFE | UARTPFIFO_TXFE,
485 sport->port.membase + UARTPFIFO);
486
487 /* flush Tx and Rx FIFO */
488 writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
489 sport->port.membase + UARTCFIFO);
490
491 /* explicitly clear RDRF */
492 if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
493 readb(sport->port.membase + UARTDR);
494 writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
495 }
496
497 writeb(0, sport->port.membase + UARTTWFIFO);
498 writeb(1, sport->port.membase + UARTRWFIFO);
499
500 /* Enable Rx and Tx */
501 writeb(UARTCR2_RE | UARTCR2_TE, sport->port.membase + UARTCR2);
502 spin_unlock_irqrestore(&sport->port.lock, flags);
503
504 return 0;
505 }
506
507 static void lpuart_poll_put_char(struct uart_port *port, unsigned char c)
508 {
509 /* drain */
510 while (!(readb(port->membase + UARTSR1) & UARTSR1_TDRE))
511 barrier();
512
513 writeb(c, port->membase + UARTDR);
514 }
515
516 static int lpuart_poll_get_char(struct uart_port *port)
517 {
518 if (!(readb(port->membase + UARTSR1) & UARTSR1_RDRF))
519 return NO_POLL_CHAR;
520
521 return readb(port->membase + UARTDR);
522 }
523
524 #endif
525
526 static inline void lpuart_transmit_buffer(struct lpuart_port *sport)
527 {
528 struct circ_buf *xmit = &sport->port.state->xmit;
529
530 while (!uart_circ_empty(xmit) &&
531 (readb(sport->port.membase + UARTTCFIFO) < sport->txfifo_size)) {
532 writeb(xmit->buf[xmit->tail], sport->port.membase + UARTDR);
533 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
534 sport->port.icount.tx++;
535 }
536
537 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
538 uart_write_wakeup(&sport->port);
539
540 if (uart_circ_empty(xmit))
541 lpuart_stop_tx(&sport->port);
542 }
543
544 static inline void lpuart32_transmit_buffer(struct lpuart_port *sport)
545 {
546 struct circ_buf *xmit = &sport->port.state->xmit;
547 unsigned long txcnt;
548
549 txcnt = lpuart32_read(&sport->port, UARTWATER);
550 txcnt = txcnt >> UARTWATER_TXCNT_OFF;
551 txcnt &= UARTWATER_COUNT_MASK;
552 while (!uart_circ_empty(xmit) && (txcnt < sport->txfifo_size)) {
553 lpuart32_write(&sport->port, xmit->buf[xmit->tail], UARTDATA);
554 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
555 sport->port.icount.tx++;
556 txcnt = lpuart32_read(&sport->port, UARTWATER);
557 txcnt = txcnt >> UARTWATER_TXCNT_OFF;
558 txcnt &= UARTWATER_COUNT_MASK;
559 }
560
561 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
562 uart_write_wakeup(&sport->port);
563
564 if (uart_circ_empty(xmit))
565 lpuart32_stop_tx(&sport->port);
566 }
567
568 static void lpuart_start_tx(struct uart_port *port)
569 {
570 struct lpuart_port *sport = container_of(port,
571 struct lpuart_port, port);
572 struct circ_buf *xmit = &sport->port.state->xmit;
573 unsigned char temp;
574
575 temp = readb(port->membase + UARTCR2);
576 writeb(temp | UARTCR2_TIE, port->membase + UARTCR2);
577
578 if (sport->lpuart_dma_tx_use) {
579 if (!uart_circ_empty(xmit) && !uart_tx_stopped(port))
580 lpuart_dma_tx(sport);
581 } else {
582 if (readb(port->membase + UARTSR1) & UARTSR1_TDRE)
583 lpuart_transmit_buffer(sport);
584 }
585 }
586
587 static void lpuart32_start_tx(struct uart_port *port)
588 {
589 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
590 unsigned long temp;
591
592 temp = lpuart32_read(port, UARTCTRL);
593 lpuart32_write(port, temp | UARTCTRL_TIE, UARTCTRL);
594
595 if (lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE)
596 lpuart32_transmit_buffer(sport);
597 }
598
599 /* return TIOCSER_TEMT when transmitter is not busy */
600 static unsigned int lpuart_tx_empty(struct uart_port *port)
601 {
602 struct lpuart_port *sport = container_of(port,
603 struct lpuart_port, port);
604 unsigned char sr1 = readb(port->membase + UARTSR1);
605 unsigned char sfifo = readb(port->membase + UARTSFIFO);
606
607 if (sport->dma_tx_in_progress)
608 return 0;
609
610 if (sr1 & UARTSR1_TC && sfifo & UARTSFIFO_TXEMPT)
611 return TIOCSER_TEMT;
612
613 return 0;
614 }
615
616 static unsigned int lpuart32_tx_empty(struct uart_port *port)
617 {
618 return (lpuart32_read(port, UARTSTAT) & UARTSTAT_TC) ?
619 TIOCSER_TEMT : 0;
620 }
621
622 static irqreturn_t lpuart_txint(int irq, void *dev_id)
623 {
624 struct lpuart_port *sport = dev_id;
625 struct circ_buf *xmit = &sport->port.state->xmit;
626 unsigned long flags;
627
628 spin_lock_irqsave(&sport->port.lock, flags);
629 if (sport->port.x_char) {
630 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
631 lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);
632 else
633 writeb(sport->port.x_char, sport->port.membase + UARTDR);
634 goto out;
635 }
636
637 if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
638 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
639 lpuart32_stop_tx(&sport->port);
640 else
641 lpuart_stop_tx(&sport->port);
642 goto out;
643 }
644
645 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
646 lpuart32_transmit_buffer(sport);
647 else
648 lpuart_transmit_buffer(sport);
649
650 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
651 uart_write_wakeup(&sport->port);
652
653 out:
654 spin_unlock_irqrestore(&sport->port.lock, flags);
655 return IRQ_HANDLED;
656 }
657
658 static irqreturn_t lpuart_rxint(int irq, void *dev_id)
659 {
660 struct lpuart_port *sport = dev_id;
661 unsigned int flg, ignored = 0;
662 struct tty_port *port = &sport->port.state->port;
663 unsigned long flags;
664 unsigned char rx, sr;
665
666 spin_lock_irqsave(&sport->port.lock, flags);
667
668 while (!(readb(sport->port.membase + UARTSFIFO) & UARTSFIFO_RXEMPT)) {
669 flg = TTY_NORMAL;
670 sport->port.icount.rx++;
671 /*
672 * to clear the FE, OR, NF, FE, PE flags,
673 * read SR1 then read DR
674 */
675 sr = readb(sport->port.membase + UARTSR1);
676 rx = readb(sport->port.membase + UARTDR);
677
678 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
679 continue;
680
681 if (sr & (UARTSR1_PE | UARTSR1_OR | UARTSR1_FE)) {
682 if (sr & UARTSR1_PE)
683 sport->port.icount.parity++;
684 else if (sr & UARTSR1_FE)
685 sport->port.icount.frame++;
686
687 if (sr & UARTSR1_OR)
688 sport->port.icount.overrun++;
689
690 if (sr & sport->port.ignore_status_mask) {
691 if (++ignored > 100)
692 goto out;
693 continue;
694 }
695
696 sr &= sport->port.read_status_mask;
697
698 if (sr & UARTSR1_PE)
699 flg = TTY_PARITY;
700 else if (sr & UARTSR1_FE)
701 flg = TTY_FRAME;
702
703 if (sr & UARTSR1_OR)
704 flg = TTY_OVERRUN;
705
706 #ifdef SUPPORT_SYSRQ
707 sport->port.sysrq = 0;
708 #endif
709 }
710
711 tty_insert_flip_char(port, rx, flg);
712 }
713
714 out:
715 spin_unlock_irqrestore(&sport->port.lock, flags);
716
717 tty_flip_buffer_push(port);
718 return IRQ_HANDLED;
719 }
720
721 static irqreturn_t lpuart32_rxint(int irq, void *dev_id)
722 {
723 struct lpuart_port *sport = dev_id;
724 unsigned int flg, ignored = 0;
725 struct tty_port *port = &sport->port.state->port;
726 unsigned long flags;
727 unsigned long rx, sr;
728
729 spin_lock_irqsave(&sport->port.lock, flags);
730
731 while (!(lpuart32_read(&sport->port, UARTFIFO) & UARTFIFO_RXEMPT)) {
732 flg = TTY_NORMAL;
733 sport->port.icount.rx++;
734 /*
735 * to clear the FE, OR, NF, FE, PE flags,
736 * read STAT then read DATA reg
737 */
738 sr = lpuart32_read(&sport->port, UARTSTAT);
739 rx = lpuart32_read(&sport->port, UARTDATA);
740 rx &= 0x3ff;
741
742 if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx))
743 continue;
744
745 if (sr & (UARTSTAT_PE | UARTSTAT_OR | UARTSTAT_FE)) {
746 if (sr & UARTSTAT_PE)
747 sport->port.icount.parity++;
748 else if (sr & UARTSTAT_FE)
749 sport->port.icount.frame++;
750
751 if (sr & UARTSTAT_OR)
752 sport->port.icount.overrun++;
753
754 if (sr & sport->port.ignore_status_mask) {
755 if (++ignored > 100)
756 goto out;
757 continue;
758 }
759
760 sr &= sport->port.read_status_mask;
761
762 if (sr & UARTSTAT_PE)
763 flg = TTY_PARITY;
764 else if (sr & UARTSTAT_FE)
765 flg = TTY_FRAME;
766
767 if (sr & UARTSTAT_OR)
768 flg = TTY_OVERRUN;
769
770 #ifdef SUPPORT_SYSRQ
771 sport->port.sysrq = 0;
772 #endif
773 }
774
775 tty_insert_flip_char(port, rx, flg);
776 }
777
778 out:
779 spin_unlock_irqrestore(&sport->port.lock, flags);
780
781 tty_flip_buffer_push(port);
782 return IRQ_HANDLED;
783 }
784
785 static irqreturn_t lpuart_int(int irq, void *dev_id)
786 {
787 struct lpuart_port *sport = dev_id;
788 unsigned char sts;
789
790 sts = readb(sport->port.membase + UARTSR1);
791
792 if (sts & UARTSR1_RDRF)
793 lpuart_rxint(irq, dev_id);
794
795 if (sts & UARTSR1_TDRE)
796 lpuart_txint(irq, dev_id);
797
798 return IRQ_HANDLED;
799 }
800
801 static irqreturn_t lpuart32_int(int irq, void *dev_id)
802 {
803 struct lpuart_port *sport = dev_id;
804 unsigned long sts, rxcount;
805
806 sts = lpuart32_read(&sport->port, UARTSTAT);
807 rxcount = lpuart32_read(&sport->port, UARTWATER);
808 rxcount = rxcount >> UARTWATER_RXCNT_OFF;
809
810 if (sts & UARTSTAT_RDRF || rxcount > 0)
811 lpuart32_rxint(irq, dev_id);
812
813 if ((sts & UARTSTAT_TDRE) &&
814 !(lpuart32_read(&sport->port, UARTBAUD) & UARTBAUD_TDMAE))
815 lpuart_txint(irq, dev_id);
816
817 lpuart32_write(&sport->port, sts, UARTSTAT);
818 return IRQ_HANDLED;
819 }
820
821 static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
822 {
823 struct tty_port *port = &sport->port.state->port;
824 struct dma_tx_state state;
825 enum dma_status dmastat;
826 struct circ_buf *ring = &sport->rx_ring;
827 unsigned long flags;
828 int count = 0;
829 unsigned char sr;
830
831 sr = readb(sport->port.membase + UARTSR1);
832
833 if (sr & (UARTSR1_PE | UARTSR1_FE)) {
834 /* Read DR to clear the error flags */
835 readb(sport->port.membase + UARTDR);
836
837 if (sr & UARTSR1_PE)
838 sport->port.icount.parity++;
839 else if (sr & UARTSR1_FE)
840 sport->port.icount.frame++;
841 }
842
843 async_tx_ack(sport->dma_rx_desc);
844
845 spin_lock_irqsave(&sport->port.lock, flags);
846
847 dmastat = dmaengine_tx_status(sport->dma_rx_chan,
848 sport->dma_rx_cookie,
849 &state);
850
851 if (dmastat == DMA_ERROR) {
852 dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
853 spin_unlock_irqrestore(&sport->port.lock, flags);
854 return;
855 }
856
857 /* CPU claims ownership of RX DMA buffer */
858 dma_sync_sg_for_cpu(sport->port.dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
859
860 /*
861 * ring->head points to the end of data already written by the DMA.
862 * ring->tail points to the beginning of data to be read by the
863 * framework.
864 * The current transfer size should not be larger than the dma buffer
865 * length.
866 */
867 ring->head = sport->rx_sgl.length - state.residue;
868 BUG_ON(ring->head > sport->rx_sgl.length);
869 /*
870 * At this point ring->head may point to the first byte right after the
871 * last byte of the dma buffer:
872 * 0 <= ring->head <= sport->rx_sgl.length
873 *
874 * However ring->tail must always points inside the dma buffer:
875 * 0 <= ring->tail <= sport->rx_sgl.length - 1
876 *
877 * Since we use a ring buffer, we have to handle the case
878 * where head is lower than tail. In such a case, we first read from
879 * tail to the end of the buffer then reset tail.
880 */
881 if (ring->head < ring->tail) {
882 count = sport->rx_sgl.length - ring->tail;
883
884 tty_insert_flip_string(port, ring->buf + ring->tail, count);
885 ring->tail = 0;
886 sport->port.icount.rx += count;
887 }
888
889 /* Finally we read data from tail to head */
890 if (ring->tail < ring->head) {
891 count = ring->head - ring->tail;
892 tty_insert_flip_string(port, ring->buf + ring->tail, count);
893 /* Wrap ring->head if needed */
894 if (ring->head >= sport->rx_sgl.length)
895 ring->head = 0;
896 ring->tail = ring->head;
897 sport->port.icount.rx += count;
898 }
899
900 dma_sync_sg_for_device(sport->port.dev, &sport->rx_sgl, 1,
901 DMA_FROM_DEVICE);
902
903 spin_unlock_irqrestore(&sport->port.lock, flags);
904
905 tty_flip_buffer_push(port);
906 mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
907 }
908
909 static void lpuart_dma_rx_complete(void *arg)
910 {
911 struct lpuart_port *sport = arg;
912
913 lpuart_copy_rx_to_tty(sport);
914 }
915
916 static void lpuart_timer_func(unsigned long data)
917 {
918 struct lpuart_port *sport = (struct lpuart_port *)data;
919
920 lpuart_copy_rx_to_tty(sport);
921 }
922
923 static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
924 {
925 struct dma_slave_config dma_rx_sconfig = {};
926 struct circ_buf *ring = &sport->rx_ring;
927 int ret, nent;
928 int bits, baud;
929 struct tty_struct *tty = tty_port_tty_get(&sport->port.state->port);
930 struct ktermios *termios = &tty->termios;
931
932 baud = tty_get_baud_rate(tty);
933
934 bits = (termios->c_cflag & CSIZE) == CS7 ? 9 : 10;
935 if (termios->c_cflag & PARENB)
936 bits++;
937
938 /*
939 * Calculate length of one DMA buffer size to keep latency below
940 * 10ms at any baud rate.
941 */
942 sport->rx_dma_rng_buf_len = (DMA_RX_TIMEOUT * baud / bits / 1000) * 2;
943 sport->rx_dma_rng_buf_len = (1 << (fls(sport->rx_dma_rng_buf_len) - 1));
944 if (sport->rx_dma_rng_buf_len < 16)
945 sport->rx_dma_rng_buf_len = 16;
946
947 ring->buf = kmalloc(sport->rx_dma_rng_buf_len, GFP_ATOMIC);
948 if (!ring->buf) {
949 dev_err(sport->port.dev, "Ring buf alloc failed\n");
950 return -ENOMEM;
951 }
952
953 sg_init_one(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
954 sg_set_buf(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
955 nent = dma_map_sg(sport->port.dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
956
957 if (!nent) {
958 dev_err(sport->port.dev, "DMA Rx mapping error\n");
959 return -EINVAL;
960 }
961
962 dma_rx_sconfig.src_addr = sport->port.mapbase + UARTDR;
963 dma_rx_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
964 dma_rx_sconfig.src_maxburst = 1;
965 dma_rx_sconfig.direction = DMA_DEV_TO_MEM;
966 ret = dmaengine_slave_config(sport->dma_rx_chan, &dma_rx_sconfig);
967
968 if (ret < 0) {
969 dev_err(sport->port.dev,
970 "DMA Rx slave config failed, err = %d\n", ret);
971 return ret;
972 }
973
974 sport->dma_rx_desc = dmaengine_prep_dma_cyclic(sport->dma_rx_chan,
975 sg_dma_address(&sport->rx_sgl),
976 sport->rx_sgl.length,
977 sport->rx_sgl.length / 2,
978 DMA_DEV_TO_MEM,
979 DMA_PREP_INTERRUPT);
980 if (!sport->dma_rx_desc) {
981 dev_err(sport->port.dev, "Cannot prepare cyclic DMA\n");
982 return -EFAULT;
983 }
984
985 sport->dma_rx_desc->callback = lpuart_dma_rx_complete;
986 sport->dma_rx_desc->callback_param = sport;
987 sport->dma_rx_cookie = dmaengine_submit(sport->dma_rx_desc);
988 dma_async_issue_pending(sport->dma_rx_chan);
989
990 writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_RDMAS,
991 sport->port.membase + UARTCR5);
992
993 return 0;
994 }
995
996 static void lpuart_dma_rx_free(struct uart_port *port)
997 {
998 struct lpuart_port *sport = container_of(port,
999 struct lpuart_port, port);
1000
1001 if (sport->dma_rx_chan)
1002 dmaengine_terminate_all(sport->dma_rx_chan);
1003
1004 dma_unmap_sg(sport->port.dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
1005 kfree(sport->rx_ring.buf);
1006 sport->rx_ring.tail = 0;
1007 sport->rx_ring.head = 0;
1008 sport->dma_rx_desc = NULL;
1009 sport->dma_rx_cookie = -EINVAL;
1010 }
1011
1012 static int lpuart_config_rs485(struct uart_port *port,
1013 struct serial_rs485 *rs485)
1014 {
1015 struct lpuart_port *sport = container_of(port,
1016 struct lpuart_port, port);
1017
1018 u8 modem = readb(sport->port.membase + UARTMODEM) &
1019 ~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE);
1020 writeb(modem, sport->port.membase + UARTMODEM);
1021
1022 if (rs485->flags & SER_RS485_ENABLED) {
1023 /* Enable auto RS-485 RTS mode */
1024 modem |= UARTMODEM_TXRTSE;
1025
1026 /*
1027 * RTS needs to be logic HIGH either during transer _or_ after
1028 * transfer, other variants are not supported by the hardware.
1029 */
1030
1031 if (!(rs485->flags & (SER_RS485_RTS_ON_SEND |
1032 SER_RS485_RTS_AFTER_SEND)))
1033 rs485->flags |= SER_RS485_RTS_ON_SEND;
1034
1035 if (rs485->flags & SER_RS485_RTS_ON_SEND &&
1036 rs485->flags & SER_RS485_RTS_AFTER_SEND)
1037 rs485->flags &= ~SER_RS485_RTS_AFTER_SEND;
1038
1039 /*
1040 * The hardware defaults to RTS logic HIGH while transfer.
1041 * Switch polarity in case RTS shall be logic HIGH
1042 * after transfer.
1043 * Note: UART is assumed to be active high.
1044 */
1045 if (rs485->flags & SER_RS485_RTS_ON_SEND)
1046 modem &= ~UARTMODEM_TXRTSPOL;
1047 else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
1048 modem |= UARTMODEM_TXRTSPOL;
1049 }
1050
1051 /* Store the new configuration */
1052 sport->port.rs485 = *rs485;
1053
1054 writeb(modem, sport->port.membase + UARTMODEM);
1055 return 0;
1056 }
1057
1058 static unsigned int lpuart_get_mctrl(struct uart_port *port)
1059 {
1060 unsigned int temp = 0;
1061 unsigned char reg;
1062
1063 reg = readb(port->membase + UARTMODEM);
1064 if (reg & UARTMODEM_TXCTSE)
1065 temp |= TIOCM_CTS;
1066
1067 if (reg & UARTMODEM_RXRTSE)
1068 temp |= TIOCM_RTS;
1069
1070 return temp;
1071 }
1072
1073 static unsigned int lpuart32_get_mctrl(struct uart_port *port)
1074 {
1075 unsigned int temp = 0;
1076 unsigned long reg;
1077
1078 reg = lpuart32_read(port, UARTMODIR);
1079 if (reg & UARTMODIR_TXCTSE)
1080 temp |= TIOCM_CTS;
1081
1082 if (reg & UARTMODIR_RXRTSE)
1083 temp |= TIOCM_RTS;
1084
1085 return temp;
1086 }
1087
1088 static void lpuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1089 {
1090 unsigned char temp;
1091 struct lpuart_port *sport = container_of(port,
1092 struct lpuart_port, port);
1093
1094 /* Make sure RXRTSE bit is not set when RS485 is enabled */
1095 if (!(sport->port.rs485.flags & SER_RS485_ENABLED)) {
1096 temp = readb(sport->port.membase + UARTMODEM) &
1097 ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1098
1099 if (mctrl & TIOCM_RTS)
1100 temp |= UARTMODEM_RXRTSE;
1101
1102 if (mctrl & TIOCM_CTS)
1103 temp |= UARTMODEM_TXCTSE;
1104
1105 writeb(temp, port->membase + UARTMODEM);
1106 }
1107 }
1108
1109 static void lpuart32_set_mctrl(struct uart_port *port, unsigned int mctrl)
1110 {
1111 unsigned long temp;
1112
1113 temp = lpuart32_read(port, UARTMODIR) &
1114 ~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE);
1115
1116 if (mctrl & TIOCM_RTS)
1117 temp |= UARTMODIR_RXRTSE;
1118
1119 if (mctrl & TIOCM_CTS)
1120 temp |= UARTMODIR_TXCTSE;
1121
1122 lpuart32_write(port, temp, UARTMODIR);
1123 }
1124
1125 static void lpuart_break_ctl(struct uart_port *port, int break_state)
1126 {
1127 unsigned char temp;
1128
1129 temp = readb(port->membase + UARTCR2) & ~UARTCR2_SBK;
1130
1131 if (break_state != 0)
1132 temp |= UARTCR2_SBK;
1133
1134 writeb(temp, port->membase + UARTCR2);
1135 }
1136
1137 static void lpuart32_break_ctl(struct uart_port *port, int break_state)
1138 {
1139 unsigned long temp;
1140
1141 temp = lpuart32_read(port, UARTCTRL) & ~UARTCTRL_SBK;
1142
1143 if (break_state != 0)
1144 temp |= UARTCTRL_SBK;
1145
1146 lpuart32_write(port, temp, UARTCTRL);
1147 }
1148
1149 static void lpuart_setup_watermark(struct lpuart_port *sport)
1150 {
1151 unsigned char val, cr2;
1152 unsigned char cr2_saved;
1153
1154 cr2 = readb(sport->port.membase + UARTCR2);
1155 cr2_saved = cr2;
1156 cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
1157 UARTCR2_RIE | UARTCR2_RE);
1158 writeb(cr2, sport->port.membase + UARTCR2);
1159
1160 val = readb(sport->port.membase + UARTPFIFO);
1161 writeb(val | UARTPFIFO_TXFE | UARTPFIFO_RXFE,
1162 sport->port.membase + UARTPFIFO);
1163
1164 /* flush Tx and Rx FIFO */
1165 writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
1166 sport->port.membase + UARTCFIFO);
1167
1168 /* explicitly clear RDRF */
1169 if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
1170 readb(sport->port.membase + UARTDR);
1171 writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
1172 }
1173
1174 writeb(0, sport->port.membase + UARTTWFIFO);
1175 writeb(1, sport->port.membase + UARTRWFIFO);
1176
1177 /* Restore cr2 */
1178 writeb(cr2_saved, sport->port.membase + UARTCR2);
1179 }
1180
1181 static void lpuart32_setup_watermark(struct lpuart_port *sport)
1182 {
1183 unsigned long val, ctrl;
1184 unsigned long ctrl_saved;
1185
1186 ctrl = lpuart32_read(&sport->port, UARTCTRL);
1187 ctrl_saved = ctrl;
1188 ctrl &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_TE |
1189 UARTCTRL_RIE | UARTCTRL_RE);
1190 lpuart32_write(&sport->port, ctrl, UARTCTRL);
1191
1192 /* enable FIFO mode */
1193 val = lpuart32_read(&sport->port, UARTFIFO);
1194 val |= UARTFIFO_TXFE | UARTFIFO_RXFE;
1195 val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
1196 lpuart32_write(&sport->port, val, UARTFIFO);
1197
1198 /* set the watermark */
1199 val = (0x1 << UARTWATER_RXWATER_OFF) | (0x0 << UARTWATER_TXWATER_OFF);
1200 lpuart32_write(&sport->port, val, UARTWATER);
1201
1202 /* Restore cr2 */
1203 lpuart32_write(&sport->port, ctrl_saved, UARTCTRL);
1204 }
1205
1206 static void rx_dma_timer_init(struct lpuart_port *sport)
1207 {
1208 setup_timer(&sport->lpuart_timer, lpuart_timer_func,
1209 (unsigned long)sport);
1210 sport->lpuart_timer.expires = jiffies + sport->dma_rx_timeout;
1211 add_timer(&sport->lpuart_timer);
1212 }
1213
1214 static int lpuart_startup(struct uart_port *port)
1215 {
1216 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1217 int ret;
1218 unsigned long flags;
1219 unsigned char temp;
1220
1221 /* determine FIFO size and enable FIFO mode */
1222 temp = readb(sport->port.membase + UARTPFIFO);
1223
1224 sport->txfifo_size = 0x1 << (((temp >> UARTPFIFO_TXSIZE_OFF) &
1225 UARTPFIFO_FIFOSIZE_MASK) + 1);
1226
1227 sport->port.fifosize = sport->txfifo_size;
1228
1229 sport->rxfifo_size = 0x1 << (((temp >> UARTPFIFO_RXSIZE_OFF) &
1230 UARTPFIFO_FIFOSIZE_MASK) + 1);
1231
1232 ret = devm_request_irq(port->dev, port->irq, lpuart_int, 0,
1233 DRIVER_NAME, sport);
1234 if (ret)
1235 return ret;
1236
1237 spin_lock_irqsave(&sport->port.lock, flags);
1238
1239 lpuart_setup_watermark(sport);
1240
1241 temp = readb(sport->port.membase + UARTCR2);
1242 temp |= (UARTCR2_RIE | UARTCR2_TIE | UARTCR2_RE | UARTCR2_TE);
1243 writeb(temp, sport->port.membase + UARTCR2);
1244
1245 if (sport->dma_rx_chan && !lpuart_start_rx_dma(sport)) {
1246 /* set Rx DMA timeout */
1247 sport->dma_rx_timeout = msecs_to_jiffies(DMA_RX_TIMEOUT);
1248 if (!sport->dma_rx_timeout)
1249 sport->dma_rx_timeout = 1;
1250
1251 sport->lpuart_dma_rx_use = true;
1252 rx_dma_timer_init(sport);
1253 } else {
1254 sport->lpuart_dma_rx_use = false;
1255 }
1256
1257 if (sport->dma_tx_chan && !lpuart_dma_tx_request(port)) {
1258 init_waitqueue_head(&sport->dma_wait);
1259 sport->lpuart_dma_tx_use = true;
1260 temp = readb(port->membase + UARTCR5);
1261 writeb(temp | UARTCR5_TDMAS, port->membase + UARTCR5);
1262 } else {
1263 sport->lpuart_dma_tx_use = false;
1264 }
1265
1266 spin_unlock_irqrestore(&sport->port.lock, flags);
1267
1268 return 0;
1269 }
1270
1271 static int lpuart32_startup(struct uart_port *port)
1272 {
1273 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1274 int ret;
1275 unsigned long flags;
1276 unsigned long temp;
1277
1278 /* determine FIFO size */
1279 temp = lpuart32_read(&sport->port, UARTFIFO);
1280
1281 sport->txfifo_size = 0x1 << (((temp >> UARTFIFO_TXSIZE_OFF) &
1282 UARTFIFO_FIFOSIZE_MASK) - 1);
1283
1284 sport->rxfifo_size = 0x1 << (((temp >> UARTFIFO_RXSIZE_OFF) &
1285 UARTFIFO_FIFOSIZE_MASK) - 1);
1286
1287 ret = devm_request_irq(port->dev, port->irq, lpuart32_int, 0,
1288 DRIVER_NAME, sport);
1289 if (ret)
1290 return ret;
1291
1292 spin_lock_irqsave(&sport->port.lock, flags);
1293
1294 lpuart32_setup_watermark(sport);
1295
1296 temp = lpuart32_read(&sport->port, UARTCTRL);
1297 temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE | UARTCTRL_TE);
1298 temp |= UARTCTRL_ILIE;
1299 lpuart32_write(&sport->port, temp, UARTCTRL);
1300
1301 spin_unlock_irqrestore(&sport->port.lock, flags);
1302 return 0;
1303 }
1304
1305 static void lpuart_shutdown(struct uart_port *port)
1306 {
1307 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1308 unsigned char temp;
1309 unsigned long flags;
1310
1311 spin_lock_irqsave(&port->lock, flags);
1312
1313 /* disable Rx/Tx and interrupts */
1314 temp = readb(port->membase + UARTCR2);
1315 temp &= ~(UARTCR2_TE | UARTCR2_RE |
1316 UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1317 writeb(temp, port->membase + UARTCR2);
1318
1319 spin_unlock_irqrestore(&port->lock, flags);
1320
1321 devm_free_irq(port->dev, port->irq, sport);
1322
1323 if (sport->lpuart_dma_rx_use) {
1324 del_timer_sync(&sport->lpuart_timer);
1325 lpuart_dma_rx_free(&sport->port);
1326 }
1327
1328 if (sport->lpuart_dma_tx_use) {
1329 if (wait_event_interruptible(sport->dma_wait,
1330 !sport->dma_tx_in_progress) != false) {
1331 sport->dma_tx_in_progress = false;
1332 dmaengine_terminate_all(sport->dma_tx_chan);
1333 }
1334
1335 lpuart_stop_tx(port);
1336 }
1337 }
1338
1339 static void lpuart32_shutdown(struct uart_port *port)
1340 {
1341 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1342 unsigned long temp;
1343 unsigned long flags;
1344
1345 spin_lock_irqsave(&port->lock, flags);
1346
1347 /* disable Rx/Tx and interrupts */
1348 temp = lpuart32_read(port, UARTCTRL);
1349 temp &= ~(UARTCTRL_TE | UARTCTRL_RE |
1350 UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
1351 lpuart32_write(port, temp, UARTCTRL);
1352
1353 spin_unlock_irqrestore(&port->lock, flags);
1354
1355 devm_free_irq(port->dev, port->irq, sport);
1356 }
1357
1358 static void
1359 lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
1360 struct ktermios *old)
1361 {
1362 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1363 unsigned long flags;
1364 unsigned char cr1, old_cr1, old_cr2, cr3, cr4, bdh, modem;
1365 unsigned int baud;
1366 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1367 unsigned int sbr, brfa;
1368
1369 cr1 = old_cr1 = readb(sport->port.membase + UARTCR1);
1370 old_cr2 = readb(sport->port.membase + UARTCR2);
1371 cr3 = readb(sport->port.membase + UARTCR3);
1372 cr4 = readb(sport->port.membase + UARTCR4);
1373 bdh = readb(sport->port.membase + UARTBDH);
1374 modem = readb(sport->port.membase + UARTMODEM);
1375 /*
1376 * only support CS8 and CS7, and for CS7 must enable PE.
1377 * supported mode:
1378 * - (7,e/o,1)
1379 * - (8,n,1)
1380 * - (8,m/s,1)
1381 * - (8,e/o,1)
1382 */
1383 while ((termios->c_cflag & CSIZE) != CS8 &&
1384 (termios->c_cflag & CSIZE) != CS7) {
1385 termios->c_cflag &= ~CSIZE;
1386 termios->c_cflag |= old_csize;
1387 old_csize = CS8;
1388 }
1389
1390 if ((termios->c_cflag & CSIZE) == CS8 ||
1391 (termios->c_cflag & CSIZE) == CS7)
1392 cr1 = old_cr1 & ~UARTCR1_M;
1393
1394 if (termios->c_cflag & CMSPAR) {
1395 if ((termios->c_cflag & CSIZE) != CS8) {
1396 termios->c_cflag &= ~CSIZE;
1397 termios->c_cflag |= CS8;
1398 }
1399 cr1 |= UARTCR1_M;
1400 }
1401
1402 /*
1403 * When auto RS-485 RTS mode is enabled,
1404 * hardware flow control need to be disabled.
1405 */
1406 if (sport->port.rs485.flags & SER_RS485_ENABLED)
1407 termios->c_cflag &= ~CRTSCTS;
1408
1409 if (termios->c_cflag & CRTSCTS) {
1410 modem |= (UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1411 } else {
1412 termios->c_cflag &= ~CRTSCTS;
1413 modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1414 }
1415
1416 if (termios->c_cflag & CSTOPB)
1417 termios->c_cflag &= ~CSTOPB;
1418
1419 /* parity must be enabled when CS7 to match 8-bits format */
1420 if ((termios->c_cflag & CSIZE) == CS7)
1421 termios->c_cflag |= PARENB;
1422
1423 if ((termios->c_cflag & PARENB)) {
1424 if (termios->c_cflag & CMSPAR) {
1425 cr1 &= ~UARTCR1_PE;
1426 if (termios->c_cflag & PARODD)
1427 cr3 |= UARTCR3_T8;
1428 else
1429 cr3 &= ~UARTCR3_T8;
1430 } else {
1431 cr1 |= UARTCR1_PE;
1432 if ((termios->c_cflag & CSIZE) == CS8)
1433 cr1 |= UARTCR1_M;
1434 if (termios->c_cflag & PARODD)
1435 cr1 |= UARTCR1_PT;
1436 else
1437 cr1 &= ~UARTCR1_PT;
1438 }
1439 }
1440
1441 /* ask the core to calculate the divisor */
1442 baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1443
1444 /*
1445 * Need to update the Ring buffer length according to the selected
1446 * baud rate and restart Rx DMA path.
1447 *
1448 * Since timer function acqures sport->port.lock, need to stop before
1449 * acquring same lock because otherwise del_timer_sync() can deadlock.
1450 */
1451 if (old && sport->lpuart_dma_rx_use) {
1452 del_timer_sync(&sport->lpuart_timer);
1453 lpuart_dma_rx_free(&sport->port);
1454 }
1455
1456 spin_lock_irqsave(&sport->port.lock, flags);
1457
1458 sport->port.read_status_mask = 0;
1459 if (termios->c_iflag & INPCK)
1460 sport->port.read_status_mask |= (UARTSR1_FE | UARTSR1_PE);
1461 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1462 sport->port.read_status_mask |= UARTSR1_FE;
1463
1464 /* characters to ignore */
1465 sport->port.ignore_status_mask = 0;
1466 if (termios->c_iflag & IGNPAR)
1467 sport->port.ignore_status_mask |= UARTSR1_PE;
1468 if (termios->c_iflag & IGNBRK) {
1469 sport->port.ignore_status_mask |= UARTSR1_FE;
1470 /*
1471 * if we're ignoring parity and break indicators,
1472 * ignore overruns too (for real raw support).
1473 */
1474 if (termios->c_iflag & IGNPAR)
1475 sport->port.ignore_status_mask |= UARTSR1_OR;
1476 }
1477
1478 /* update the per-port timeout */
1479 uart_update_timeout(port, termios->c_cflag, baud);
1480
1481 /* wait transmit engin complete */
1482 while (!(readb(sport->port.membase + UARTSR1) & UARTSR1_TC))
1483 barrier();
1484
1485 /* disable transmit and receive */
1486 writeb(old_cr2 & ~(UARTCR2_TE | UARTCR2_RE),
1487 sport->port.membase + UARTCR2);
1488
1489 sbr = sport->port.uartclk / (16 * baud);
1490 brfa = ((sport->port.uartclk - (16 * sbr * baud)) * 2) / baud;
1491 bdh &= ~UARTBDH_SBR_MASK;
1492 bdh |= (sbr >> 8) & 0x1F;
1493 cr4 &= ~UARTCR4_BRFA_MASK;
1494 brfa &= UARTCR4_BRFA_MASK;
1495 writeb(cr4 | brfa, sport->port.membase + UARTCR4);
1496 writeb(bdh, sport->port.membase + UARTBDH);
1497 writeb(sbr & 0xFF, sport->port.membase + UARTBDL);
1498 writeb(cr3, sport->port.membase + UARTCR3);
1499 writeb(cr1, sport->port.membase + UARTCR1);
1500 writeb(modem, sport->port.membase + UARTMODEM);
1501
1502 /* restore control register */
1503 writeb(old_cr2, sport->port.membase + UARTCR2);
1504
1505 if (old && sport->lpuart_dma_rx_use) {
1506 if (!lpuart_start_rx_dma(sport))
1507 rx_dma_timer_init(sport);
1508 else
1509 sport->lpuart_dma_rx_use = false;
1510 }
1511
1512 spin_unlock_irqrestore(&sport->port.lock, flags);
1513 }
1514
1515 static void
1516 lpuart32_serial_setbrg(struct lpuart_port *sport, unsigned int baudrate)
1517 {
1518 u32 sbr, osr, baud_diff, tmp_osr, tmp_sbr, tmp_diff, tmp;
1519 u32 clk = sport->port.uartclk;
1520
1521 /*
1522 * The idea is to use the best OSR (over-sampling rate) possible.
1523 * Note, OSR is typically hard-set to 16 in other LPUART instantiations.
1524 * Loop to find the best OSR value possible, one that generates minimum
1525 * baud_diff iterate through the rest of the supported values of OSR.
1526 *
1527 * Calculation Formula:
1528 * Baud Rate = baud clock / ((OSR+1) × SBR)
1529 */
1530 baud_diff = baudrate;
1531 osr = 0;
1532 sbr = 0;
1533
1534 for (tmp_osr = 4; tmp_osr <= 32; tmp_osr++) {
1535 /* calculate the temporary sbr value */
1536 tmp_sbr = (clk / (baudrate * tmp_osr));
1537 if (tmp_sbr == 0)
1538 tmp_sbr = 1;
1539
1540 /*
1541 * calculate the baud rate difference based on the temporary
1542 * osr and sbr values
1543 */
1544 tmp_diff = clk / (tmp_osr * tmp_sbr) - baudrate;
1545
1546 /* select best values between sbr and sbr+1 */
1547 tmp = clk / (tmp_osr * (tmp_sbr + 1));
1548 if (tmp_diff > (baudrate - tmp)) {
1549 tmp_diff = baudrate - tmp;
1550 tmp_sbr++;
1551 }
1552
1553 if (tmp_diff <= baud_diff) {
1554 baud_diff = tmp_diff;
1555 osr = tmp_osr;
1556 sbr = tmp_sbr;
1557
1558 if (!baud_diff)
1559 break;
1560 }
1561 }
1562
1563 /* handle buadrate outside acceptable rate */
1564 if (baud_diff > ((baudrate / 100) * 3))
1565 dev_warn(sport->port.dev,
1566 "unacceptable baud rate difference of more than 3%%\n");
1567
1568 tmp = lpuart32_read(&sport->port, UARTBAUD);
1569
1570 if ((osr > 3) && (osr < 8))
1571 tmp |= UARTBAUD_BOTHEDGE;
1572
1573 tmp &= ~(UARTBAUD_OSR_MASK << UARTBAUD_OSR_SHIFT);
1574 tmp |= (((osr-1) & UARTBAUD_OSR_MASK) << UARTBAUD_OSR_SHIFT);
1575
1576 tmp &= ~UARTBAUD_SBR_MASK;
1577 tmp |= sbr & UARTBAUD_SBR_MASK;
1578
1579 tmp &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE);
1580
1581 lpuart32_write(&sport->port, tmp, UARTBAUD);
1582 }
1583
1584 static void
1585 lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
1586 struct ktermios *old)
1587 {
1588 struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1589 unsigned long flags;
1590 unsigned long ctrl, old_ctrl, bd, modem;
1591 unsigned int baud;
1592 unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1593
1594 ctrl = old_ctrl = lpuart32_read(&sport->port, UARTCTRL);
1595 bd = lpuart32_read(&sport->port, UARTBAUD);
1596 modem = lpuart32_read(&sport->port, UARTMODIR);
1597 /*
1598 * only support CS8 and CS7, and for CS7 must enable PE.
1599 * supported mode:
1600 * - (7,e/o,1)
1601 * - (8,n,1)
1602 * - (8,m/s,1)
1603 * - (8,e/o,1)
1604 */
1605 while ((termios->c_cflag & CSIZE) != CS8 &&
1606 (termios->c_cflag & CSIZE) != CS7) {
1607 termios->c_cflag &= ~CSIZE;
1608 termios->c_cflag |= old_csize;
1609 old_csize = CS8;
1610 }
1611
1612 if ((termios->c_cflag & CSIZE) == CS8 ||
1613 (termios->c_cflag & CSIZE) == CS7)
1614 ctrl = old_ctrl & ~UARTCTRL_M;
1615
1616 if (termios->c_cflag & CMSPAR) {
1617 if ((termios->c_cflag & CSIZE) != CS8) {
1618 termios->c_cflag &= ~CSIZE;
1619 termios->c_cflag |= CS8;
1620 }
1621 ctrl |= UARTCTRL_M;
1622 }
1623
1624 if (termios->c_cflag & CRTSCTS) {
1625 modem |= (UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1626 } else {
1627 termios->c_cflag &= ~CRTSCTS;
1628 modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1629 }
1630
1631 if (termios->c_cflag & CSTOPB)
1632 termios->c_cflag &= ~CSTOPB;
1633
1634 /* parity must be enabled when CS7 to match 8-bits format */
1635 if ((termios->c_cflag & CSIZE) == CS7)
1636 termios->c_cflag |= PARENB;
1637
1638 if ((termios->c_cflag & PARENB)) {
1639 if (termios->c_cflag & CMSPAR) {
1640 ctrl &= ~UARTCTRL_PE;
1641 ctrl |= UARTCTRL_M;
1642 } else {
1643 ctrl |= UARTCR1_PE;
1644 if ((termios->c_cflag & CSIZE) == CS8)
1645 ctrl |= UARTCTRL_M;
1646 if (termios->c_cflag & PARODD)
1647 ctrl |= UARTCTRL_PT;
1648 else
1649 ctrl &= ~UARTCTRL_PT;
1650 }
1651 }
1652
1653 /* ask the core to calculate the divisor */
1654 baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1655
1656 spin_lock_irqsave(&sport->port.lock, flags);
1657
1658 sport->port.read_status_mask = 0;
1659 if (termios->c_iflag & INPCK)
1660 sport->port.read_status_mask |= (UARTSTAT_FE | UARTSTAT_PE);
1661 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1662 sport->port.read_status_mask |= UARTSTAT_FE;
1663
1664 /* characters to ignore */
1665 sport->port.ignore_status_mask = 0;
1666 if (termios->c_iflag & IGNPAR)
1667 sport->port.ignore_status_mask |= UARTSTAT_PE;
1668 if (termios->c_iflag & IGNBRK) {
1669 sport->port.ignore_status_mask |= UARTSTAT_FE;
1670 /*
1671 * if we're ignoring parity and break indicators,
1672 * ignore overruns too (for real raw support).
1673 */
1674 if (termios->c_iflag & IGNPAR)
1675 sport->port.ignore_status_mask |= UARTSTAT_OR;
1676 }
1677
1678 /* update the per-port timeout */
1679 uart_update_timeout(port, termios->c_cflag, baud);
1680
1681 /* wait transmit engin complete */
1682 while (!(lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_TC))
1683 barrier();
1684
1685 /* disable transmit and receive */
1686 lpuart32_write(&sport->port, old_ctrl & ~(UARTCTRL_TE | UARTCTRL_RE),
1687 UARTCTRL);
1688
1689 lpuart32_serial_setbrg(sport, baud);
1690 lpuart32_write(&sport->port, modem, UARTMODIR);
1691 lpuart32_write(&sport->port, ctrl, UARTCTRL);
1692 /* restore control register */
1693
1694 spin_unlock_irqrestore(&sport->port.lock, flags);
1695 }
1696
1697 static const char *lpuart_type(struct uart_port *port)
1698 {
1699 return "FSL_LPUART";
1700 }
1701
1702 static void lpuart_release_port(struct uart_port *port)
1703 {
1704 /* nothing to do */
1705 }
1706
1707 static int lpuart_request_port(struct uart_port *port)
1708 {
1709 return 0;
1710 }
1711
1712 /* configure/autoconfigure the port */
1713 static void lpuart_config_port(struct uart_port *port, int flags)
1714 {
1715 if (flags & UART_CONFIG_TYPE)
1716 port->type = PORT_LPUART;
1717 }
1718
1719 static int lpuart_verify_port(struct uart_port *port, struct serial_struct *ser)
1720 {
1721 int ret = 0;
1722
1723 if (ser->type != PORT_UNKNOWN && ser->type != PORT_LPUART)
1724 ret = -EINVAL;
1725 if (port->irq != ser->irq)
1726 ret = -EINVAL;
1727 if (ser->io_type != UPIO_MEM)
1728 ret = -EINVAL;
1729 if (port->uartclk / 16 != ser->baud_base)
1730 ret = -EINVAL;
1731 if (port->iobase != ser->port)
1732 ret = -EINVAL;
1733 if (ser->hub6 != 0)
1734 ret = -EINVAL;
1735 return ret;
1736 }
1737
1738 static const struct uart_ops lpuart_pops = {
1739 .tx_empty = lpuart_tx_empty,
1740 .set_mctrl = lpuart_set_mctrl,
1741 .get_mctrl = lpuart_get_mctrl,
1742 .stop_tx = lpuart_stop_tx,
1743 .start_tx = lpuart_start_tx,
1744 .stop_rx = lpuart_stop_rx,
1745 .break_ctl = lpuart_break_ctl,
1746 .startup = lpuart_startup,
1747 .shutdown = lpuart_shutdown,
1748 .set_termios = lpuart_set_termios,
1749 .type = lpuart_type,
1750 .request_port = lpuart_request_port,
1751 .release_port = lpuart_release_port,
1752 .config_port = lpuart_config_port,
1753 .verify_port = lpuart_verify_port,
1754 .flush_buffer = lpuart_flush_buffer,
1755 #if defined(CONFIG_CONSOLE_POLL)
1756 .poll_init = lpuart_poll_init,
1757 .poll_get_char = lpuart_poll_get_char,
1758 .poll_put_char = lpuart_poll_put_char,
1759 #endif
1760 };
1761
1762 static const struct uart_ops lpuart32_pops = {
1763 .tx_empty = lpuart32_tx_empty,
1764 .set_mctrl = lpuart32_set_mctrl,
1765 .get_mctrl = lpuart32_get_mctrl,
1766 .stop_tx = lpuart32_stop_tx,
1767 .start_tx = lpuart32_start_tx,
1768 .stop_rx = lpuart32_stop_rx,
1769 .break_ctl = lpuart32_break_ctl,
1770 .startup = lpuart32_startup,
1771 .shutdown = lpuart32_shutdown,
1772 .set_termios = lpuart32_set_termios,
1773 .type = lpuart_type,
1774 .request_port = lpuart_request_port,
1775 .release_port = lpuart_release_port,
1776 .config_port = lpuart_config_port,
1777 .verify_port = lpuart_verify_port,
1778 .flush_buffer = lpuart_flush_buffer,
1779 };
1780
1781 static struct lpuart_port *lpuart_ports[UART_NR];
1782
1783 #ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
1784 static void lpuart_console_putchar(struct uart_port *port, int ch)
1785 {
1786 while (!(readb(port->membase + UARTSR1) & UARTSR1_TDRE))
1787 barrier();
1788
1789 writeb(ch, port->membase + UARTDR);
1790 }
1791
1792 static void lpuart32_console_putchar(struct uart_port *port, int ch)
1793 {
1794 while (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE))
1795 barrier();
1796
1797 lpuart32_write(port, ch, UARTDATA);
1798 }
1799
1800 static void
1801 lpuart_console_write(struct console *co, const char *s, unsigned int count)
1802 {
1803 struct lpuart_port *sport = lpuart_ports[co->index];
1804 unsigned char old_cr2, cr2;
1805 unsigned long flags;
1806 int locked = 1;
1807
1808 if (sport->port.sysrq || oops_in_progress)
1809 locked = spin_trylock_irqsave(&sport->port.lock, flags);
1810 else
1811 spin_lock_irqsave(&sport->port.lock, flags);
1812
1813 /* first save CR2 and then disable interrupts */
1814 cr2 = old_cr2 = readb(sport->port.membase + UARTCR2);
1815 cr2 |= (UARTCR2_TE | UARTCR2_RE);
1816 cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1817 writeb(cr2, sport->port.membase + UARTCR2);
1818
1819 uart_console_write(&sport->port, s, count, lpuart_console_putchar);
1820
1821 /* wait for transmitter finish complete and restore CR2 */
1822 while (!(readb(sport->port.membase + UARTSR1) & UARTSR1_TC))
1823 barrier();
1824
1825 writeb(old_cr2, sport->port.membase + UARTCR2);
1826
1827 if (locked)
1828 spin_unlock_irqrestore(&sport->port.lock, flags);
1829 }
1830
1831 static void
1832 lpuart32_console_write(struct console *co, const char *s, unsigned int count)
1833 {
1834 struct lpuart_port *sport = lpuart_ports[co->index];
1835 unsigned long old_cr, cr;
1836 unsigned long flags;
1837 int locked = 1;
1838
1839 if (sport->port.sysrq || oops_in_progress)
1840 locked = spin_trylock_irqsave(&sport->port.lock, flags);
1841 else
1842 spin_lock_irqsave(&sport->port.lock, flags);
1843
1844 /* first save CR2 and then disable interrupts */
1845 cr = old_cr = lpuart32_read(&sport->port, UARTCTRL);
1846 cr |= (UARTCTRL_TE | UARTCTRL_RE);
1847 cr &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
1848 lpuart32_write(&sport->port, cr, UARTCTRL);
1849
1850 uart_console_write(&sport->port, s, count, lpuart32_console_putchar);
1851
1852 /* wait for transmitter finish complete and restore CR2 */
1853 while (!(lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_TC))
1854 barrier();
1855
1856 lpuart32_write(&sport->port, old_cr, UARTCTRL);
1857
1858 if (locked)
1859 spin_unlock_irqrestore(&sport->port.lock, flags);
1860 }
1861
1862 /*
1863 * if the port was already initialised (eg, by a boot loader),
1864 * try to determine the current setup.
1865 */
1866 static void __init
1867 lpuart_console_get_options(struct lpuart_port *sport, int *baud,
1868 int *parity, int *bits)
1869 {
1870 unsigned char cr, bdh, bdl, brfa;
1871 unsigned int sbr, uartclk, baud_raw;
1872
1873 cr = readb(sport->port.membase + UARTCR2);
1874 cr &= UARTCR2_TE | UARTCR2_RE;
1875 if (!cr)
1876 return;
1877
1878 /* ok, the port was enabled */
1879
1880 cr = readb(sport->port.membase + UARTCR1);
1881
1882 *parity = 'n';
1883 if (cr & UARTCR1_PE) {
1884 if (cr & UARTCR1_PT)
1885 *parity = 'o';
1886 else
1887 *parity = 'e';
1888 }
1889
1890 if (cr & UARTCR1_M)
1891 *bits = 9;
1892 else
1893 *bits = 8;
1894
1895 bdh = readb(sport->port.membase + UARTBDH);
1896 bdh &= UARTBDH_SBR_MASK;
1897 bdl = readb(sport->port.membase + UARTBDL);
1898 sbr = bdh;
1899 sbr <<= 8;
1900 sbr |= bdl;
1901 brfa = readb(sport->port.membase + UARTCR4);
1902 brfa &= UARTCR4_BRFA_MASK;
1903
1904 uartclk = clk_get_rate(sport->clk);
1905 /*
1906 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
1907 */
1908 baud_raw = uartclk / (16 * (sbr + brfa / 32));
1909
1910 if (*baud != baud_raw)
1911 printk(KERN_INFO "Serial: Console lpuart rounded baud rate"
1912 "from %d to %d\n", baud_raw, *baud);
1913 }
1914
1915 static void __init
1916 lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
1917 int *parity, int *bits)
1918 {
1919 unsigned long cr, bd;
1920 unsigned int sbr, uartclk, baud_raw;
1921
1922 cr = lpuart32_read(&sport->port, UARTCTRL);
1923 cr &= UARTCTRL_TE | UARTCTRL_RE;
1924 if (!cr)
1925 return;
1926
1927 /* ok, the port was enabled */
1928
1929 cr = lpuart32_read(&sport->port, UARTCTRL);
1930
1931 *parity = 'n';
1932 if (cr & UARTCTRL_PE) {
1933 if (cr & UARTCTRL_PT)
1934 *parity = 'o';
1935 else
1936 *parity = 'e';
1937 }
1938
1939 if (cr & UARTCTRL_M)
1940 *bits = 9;
1941 else
1942 *bits = 8;
1943
1944 bd = lpuart32_read(&sport->port, UARTBAUD);
1945 bd &= UARTBAUD_SBR_MASK;
1946 sbr = bd;
1947 uartclk = clk_get_rate(sport->clk);
1948 /*
1949 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
1950 */
1951 baud_raw = uartclk / (16 * sbr);
1952
1953 if (*baud != baud_raw)
1954 printk(KERN_INFO "Serial: Console lpuart rounded baud rate"
1955 "from %d to %d\n", baud_raw, *baud);
1956 }
1957
1958 static int __init lpuart_console_setup(struct console *co, char *options)
1959 {
1960 struct lpuart_port *sport;
1961 int baud = 115200;
1962 int bits = 8;
1963 int parity = 'n';
1964 int flow = 'n';
1965
1966 /*
1967 * check whether an invalid uart number has been specified, and
1968 * if so, search for the first available port that does have
1969 * console support.
1970 */
1971 if (co->index == -1 || co->index >= ARRAY_SIZE(lpuart_ports))
1972 co->index = 0;
1973
1974 sport = lpuart_ports[co->index];
1975 if (sport == NULL)
1976 return -ENODEV;
1977
1978 if (options)
1979 uart_parse_options(options, &baud, &parity, &bits, &flow);
1980 else
1981 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
1982 lpuart32_console_get_options(sport, &baud, &parity, &bits);
1983 else
1984 lpuart_console_get_options(sport, &baud, &parity, &bits);
1985
1986 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
1987 lpuart32_setup_watermark(sport);
1988 else
1989 lpuart_setup_watermark(sport);
1990
1991 return uart_set_options(&sport->port, co, baud, parity, bits, flow);
1992 }
1993
1994 static struct uart_driver lpuart_reg;
1995 static struct console lpuart_console = {
1996 .name = DEV_NAME,
1997 .write = lpuart_console_write,
1998 .device = uart_console_device,
1999 .setup = lpuart_console_setup,
2000 .flags = CON_PRINTBUFFER,
2001 .index = -1,
2002 .data = &lpuart_reg,
2003 };
2004
2005 static struct console lpuart32_console = {
2006 .name = DEV_NAME,
2007 .write = lpuart32_console_write,
2008 .device = uart_console_device,
2009 .setup = lpuart_console_setup,
2010 .flags = CON_PRINTBUFFER,
2011 .index = -1,
2012 .data = &lpuart_reg,
2013 };
2014
2015 static void lpuart_early_write(struct console *con, const char *s, unsigned n)
2016 {
2017 struct earlycon_device *dev = con->data;
2018
2019 uart_console_write(&dev->port, s, n, lpuart_console_putchar);
2020 }
2021
2022 static void lpuart32_early_write(struct console *con, const char *s, unsigned n)
2023 {
2024 struct earlycon_device *dev = con->data;
2025
2026 uart_console_write(&dev->port, s, n, lpuart32_console_putchar);
2027 }
2028
2029 static int __init lpuart_early_console_setup(struct earlycon_device *device,
2030 const char *opt)
2031 {
2032 if (!device->port.membase)
2033 return -ENODEV;
2034
2035 device->con->write = lpuart_early_write;
2036 return 0;
2037 }
2038
2039 static int __init lpuart32_early_console_setup(struct earlycon_device *device,
2040 const char *opt)
2041 {
2042 if (!device->port.membase)
2043 return -ENODEV;
2044
2045 device->port.iotype = UPIO_MEM32BE;
2046 device->con->write = lpuart32_early_write;
2047 return 0;
2048 }
2049
2050 static int __init lpuart32_imx_early_console_setup(struct earlycon_device *device,
2051 const char *opt)
2052 {
2053 if (!device->port.membase)
2054 return -ENODEV;
2055
2056 device->port.iotype = UPIO_MEM32;
2057 device->port.membase += IMX_REG_OFF;
2058 device->con->write = lpuart32_early_write;
2059
2060 return 0;
2061 }
2062 OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
2063 OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
2064 OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup);
2065 EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
2066 EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);
2067
2068 #define LPUART_CONSOLE (&lpuart_console)
2069 #define LPUART32_CONSOLE (&lpuart32_console)
2070 #else
2071 #define LPUART_CONSOLE NULL
2072 #define LPUART32_CONSOLE NULL
2073 #endif
2074
2075 static struct uart_driver lpuart_reg = {
2076 .owner = THIS_MODULE,
2077 .driver_name = DRIVER_NAME,
2078 .dev_name = DEV_NAME,
2079 .nr = ARRAY_SIZE(lpuart_ports),
2080 .cons = LPUART_CONSOLE,
2081 };
2082
2083 static int lpuart_probe(struct platform_device *pdev)
2084 {
2085 const struct of_device_id *of_id = of_match_device(lpuart_dt_ids,
2086 &pdev->dev);
2087 const struct lpuart_soc_data *sdata = of_id->data;
2088 struct device_node *np = pdev->dev.of_node;
2089 struct lpuart_port *sport;
2090 struct resource *res;
2091 int ret;
2092
2093 sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
2094 if (!sport)
2095 return -ENOMEM;
2096
2097 pdev->dev.coherent_dma_mask = 0;
2098
2099 ret = of_alias_get_id(np, "serial");
2100 if (ret < 0) {
2101 dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
2102 return ret;
2103 }
2104 sport->port.line = ret;
2105 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2106 sport->port.membase = devm_ioremap_resource(&pdev->dev, res);
2107 if (IS_ERR(sport->port.membase))
2108 return PTR_ERR(sport->port.membase);
2109
2110 sport->port.membase += sdata->reg_off;
2111 sport->port.mapbase = res->start;
2112 sport->port.dev = &pdev->dev;
2113 sport->port.type = PORT_LPUART;
2114 ret = platform_get_irq(pdev, 0);
2115 if (ret < 0) {
2116 dev_err(&pdev->dev, "cannot obtain irq\n");
2117 return ret;
2118 }
2119 sport->port.irq = ret;
2120 sport->port.iotype = sdata->iotype;
2121 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
2122 sport->port.ops = &lpuart32_pops;
2123 else
2124 sport->port.ops = &lpuart_pops;
2125 sport->port.flags = UPF_BOOT_AUTOCONF;
2126
2127 sport->port.rs485_config = lpuart_config_rs485;
2128
2129 sport->clk = devm_clk_get(&pdev->dev, "ipg");
2130 if (IS_ERR(sport->clk)) {
2131 ret = PTR_ERR(sport->clk);
2132 dev_err(&pdev->dev, "failed to get uart clk: %d\n", ret);
2133 return ret;
2134 }
2135
2136 ret = clk_prepare_enable(sport->clk);
2137 if (ret) {
2138 dev_err(&pdev->dev, "failed to enable uart clk: %d\n", ret);
2139 return ret;
2140 }
2141
2142 sport->port.uartclk = clk_get_rate(sport->clk);
2143
2144 lpuart_ports[sport->port.line] = sport;
2145
2146 platform_set_drvdata(pdev, &sport->port);
2147
2148 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
2149 lpuart_reg.cons = LPUART32_CONSOLE;
2150 else
2151 lpuart_reg.cons = LPUART_CONSOLE;
2152
2153 ret = uart_add_one_port(&lpuart_reg, &sport->port);
2154 if (ret) {
2155 clk_disable_unprepare(sport->clk);
2156 return ret;
2157 }
2158
2159 sport->dma_tx_chan = dma_request_slave_channel(sport->port.dev, "tx");
2160 if (!sport->dma_tx_chan)
2161 dev_info(sport->port.dev, "DMA tx channel request failed, "
2162 "operating without tx DMA\n");
2163
2164 sport->dma_rx_chan = dma_request_slave_channel(sport->port.dev, "rx");
2165 if (!sport->dma_rx_chan)
2166 dev_info(sport->port.dev, "DMA rx channel request failed, "
2167 "operating without rx DMA\n");
2168
2169 if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time")) {
2170 sport->port.rs485.flags |= SER_RS485_ENABLED;
2171 sport->port.rs485.flags |= SER_RS485_RTS_ON_SEND;
2172 writeb(UARTMODEM_TXRTSE, sport->port.membase + UARTMODEM);
2173 }
2174
2175 return 0;
2176 }
2177
2178 static int lpuart_remove(struct platform_device *pdev)
2179 {
2180 struct lpuart_port *sport = platform_get_drvdata(pdev);
2181
2182 uart_remove_one_port(&lpuart_reg, &sport->port);
2183
2184 clk_disable_unprepare(sport->clk);
2185
2186 if (sport->dma_tx_chan)
2187 dma_release_channel(sport->dma_tx_chan);
2188
2189 if (sport->dma_rx_chan)
2190 dma_release_channel(sport->dma_rx_chan);
2191
2192 return 0;
2193 }
2194
2195 #ifdef CONFIG_PM_SLEEP
2196 static int lpuart_suspend(struct device *dev)
2197 {
2198 struct lpuart_port *sport = dev_get_drvdata(dev);
2199 unsigned long temp;
2200
2201 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE)) {
2202 /* disable Rx/Tx and interrupts */
2203 temp = lpuart32_read(&sport->port, UARTCTRL);
2204 temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
2205 lpuart32_write(&sport->port, temp, UARTCTRL);
2206 } else {
2207 /* disable Rx/Tx and interrupts */
2208 temp = readb(sport->port.membase + UARTCR2);
2209 temp &= ~(UARTCR2_TE | UARTCR2_TIE | UARTCR2_TCIE);
2210 writeb(temp, sport->port.membase + UARTCR2);
2211 }
2212
2213 uart_suspend_port(&lpuart_reg, &sport->port);
2214
2215 if (sport->lpuart_dma_rx_use) {
2216 /*
2217 * EDMA driver during suspend will forcefully release any
2218 * non-idle DMA channels. If port wakeup is enabled or if port
2219 * is console port or 'no_console_suspend' is set the Rx DMA
2220 * cannot resume as as expected, hence gracefully release the
2221 * Rx DMA path before suspend and start Rx DMA path on resume.
2222 */
2223 if (sport->port.irq_wake) {
2224 del_timer_sync(&sport->lpuart_timer);
2225 lpuart_dma_rx_free(&sport->port);
2226 }
2227
2228 /* Disable Rx DMA to use UART port as wakeup source */
2229 writeb(readb(sport->port.membase + UARTCR5) & ~UARTCR5_RDMAS,
2230 sport->port.membase + UARTCR5);
2231 }
2232
2233 if (sport->lpuart_dma_tx_use) {
2234 sport->dma_tx_in_progress = false;
2235 dmaengine_terminate_all(sport->dma_tx_chan);
2236 }
2237
2238 if (sport->port.suspended && !sport->port.irq_wake)
2239 clk_disable_unprepare(sport->clk);
2240
2241 return 0;
2242 }
2243
2244 static int lpuart_resume(struct device *dev)
2245 {
2246 struct lpuart_port *sport = dev_get_drvdata(dev);
2247 unsigned long temp;
2248
2249 if (sport->port.suspended && !sport->port.irq_wake)
2250 clk_prepare_enable(sport->clk);
2251
2252 if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE)) {
2253 lpuart32_setup_watermark(sport);
2254 temp = lpuart32_read(&sport->port, UARTCTRL);
2255 temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE |
2256 UARTCTRL_TE | UARTCTRL_ILIE);
2257 lpuart32_write(&sport->port, temp, UARTCTRL);
2258 } else {
2259 lpuart_setup_watermark(sport);
2260 temp = readb(sport->port.membase + UARTCR2);
2261 temp |= (UARTCR2_RIE | UARTCR2_TIE | UARTCR2_RE | UARTCR2_TE);
2262 writeb(temp, sport->port.membase + UARTCR2);
2263 }
2264
2265 if (sport->lpuart_dma_rx_use) {
2266 if (sport->port.irq_wake) {
2267 if (!lpuart_start_rx_dma(sport))
2268 rx_dma_timer_init(sport);
2269 else
2270 sport->lpuart_dma_rx_use = false;
2271 }
2272 }
2273
2274 if (sport->dma_tx_chan && !lpuart_dma_tx_request(&sport->port)) {
2275 init_waitqueue_head(&sport->dma_wait);
2276 sport->lpuart_dma_tx_use = true;
2277 writeb(readb(sport->port.membase + UARTCR5) |
2278 UARTCR5_TDMAS, sport->port.membase + UARTCR5);
2279 } else {
2280 sport->lpuart_dma_tx_use = false;
2281 }
2282
2283 uart_resume_port(&lpuart_reg, &sport->port);
2284
2285 return 0;
2286 }
2287 #endif
2288
2289 static SIMPLE_DEV_PM_OPS(lpuart_pm_ops, lpuart_suspend, lpuart_resume);
2290
2291 static struct platform_driver lpuart_driver = {
2292 .probe = lpuart_probe,
2293 .remove = lpuart_remove,
2294 .driver = {
2295 .name = "fsl-lpuart",
2296 .of_match_table = lpuart_dt_ids,
2297 .pm = &lpuart_pm_ops,
2298 },
2299 };
2300
2301 static int __init lpuart_serial_init(void)
2302 {
2303 int ret = uart_register_driver(&lpuart_reg);
2304
2305 if (ret)
2306 return ret;
2307
2308 ret = platform_driver_register(&lpuart_driver);
2309 if (ret)
2310 uart_unregister_driver(&lpuart_reg);
2311
2312 return ret;
2313 }
2314
2315 static void __exit lpuart_serial_exit(void)
2316 {
2317 platform_driver_unregister(&lpuart_driver);
2318 uart_unregister_driver(&lpuart_reg);
2319 }
2320
2321 module_init(lpuart_serial_init);
2322 module_exit(lpuart_serial_exit);
2323
2324 MODULE_DESCRIPTION("Freescale lpuart serial port driver");
2325 MODULE_LICENSE("GPL v2");
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