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1// SPDX-License-Identifier: GPL-2.0+
2/*
3* ***************************************************************************
4* Marvell Armada-3700 Serial Driver
5* Author: Wilson Ding <dingwei@marvell.com>
6* Copyright (C) 2015 Marvell International Ltd.
7* ***************************************************************************
8*/
9
10#include <linux/clk.h>
11#include <linux/console.h>
12#include <linux/delay.h>
13#include <linux/device.h>
14#include <linux/init.h>
15#include <linux/io.h>
16#include <linux/iopoll.h>
17#include <linux/of.h>
18#include <linux/of_address.h>
19#include <linux/of_device.h>
20#include <linux/of_irq.h>
21#include <linux/of_platform.h>
22#include <linux/platform_device.h>
23#include <linux/serial.h>
24#include <linux/serial_core.h>
25#include <linux/slab.h>
26#include <linux/tty.h>
27#include <linux/tty_flip.h>
28
29/* Register Map */
30#define UART_STD_RBR 0x00
31#define UART_EXT_RBR 0x18
32
33#define UART_STD_TSH 0x04
34#define UART_EXT_TSH 0x1C
35
36#define UART_STD_CTRL1 0x08
37#define UART_EXT_CTRL1 0x04
38#define CTRL_SOFT_RST BIT(31)
39#define CTRL_TXFIFO_RST BIT(15)
40#define CTRL_RXFIFO_RST BIT(14)
41#define CTRL_SND_BRK_SEQ BIT(11)
42#define CTRL_BRK_DET_INT BIT(3)
43#define CTRL_FRM_ERR_INT BIT(2)
44#define CTRL_PAR_ERR_INT BIT(1)
45#define CTRL_OVR_ERR_INT BIT(0)
46#define CTRL_BRK_INT (CTRL_BRK_DET_INT | CTRL_FRM_ERR_INT | \
47 CTRL_PAR_ERR_INT | CTRL_OVR_ERR_INT)
48
49#define UART_STD_CTRL2 UART_STD_CTRL1
50#define UART_EXT_CTRL2 0x20
51#define CTRL_STD_TX_RDY_INT BIT(5)
52#define CTRL_EXT_TX_RDY_INT BIT(6)
53#define CTRL_STD_RX_RDY_INT BIT(4)
54#define CTRL_EXT_RX_RDY_INT BIT(5)
55
56#define UART_STAT 0x0C
57#define STAT_TX_FIFO_EMP BIT(13)
58#define STAT_TX_FIFO_FUL BIT(11)
59#define STAT_TX_EMP BIT(6)
60#define STAT_STD_TX_RDY BIT(5)
61#define STAT_EXT_TX_RDY BIT(15)
62#define STAT_STD_RX_RDY BIT(4)
63#define STAT_EXT_RX_RDY BIT(14)
64#define STAT_BRK_DET BIT(3)
65#define STAT_FRM_ERR BIT(2)
66#define STAT_PAR_ERR BIT(1)
67#define STAT_OVR_ERR BIT(0)
68#define STAT_BRK_ERR (STAT_BRK_DET | STAT_FRM_ERR \
69 | STAT_PAR_ERR | STAT_OVR_ERR)
70
71#define UART_BRDV 0x10
72#define BRDV_BAUD_MASK 0x3FF
73
74#define MVEBU_NR_UARTS 2
75
76#define MVEBU_UART_TYPE "mvebu-uart"
77#define DRIVER_NAME "mvebu_serial"
78
79enum {
80 /* Either there is only one summed IRQ... */
81 UART_IRQ_SUM = 0,
82 /* ...or there are two separate IRQ for RX and TX */
83 UART_RX_IRQ = 0,
84 UART_TX_IRQ,
85 UART_IRQ_COUNT
86};
87
88/* Diverging register offsets */
89struct uart_regs_layout {
90 unsigned int rbr;
91 unsigned int tsh;
92 unsigned int ctrl;
93 unsigned int intr;
94};
95
96/* Diverging flags */
97struct uart_flags {
98 unsigned int ctrl_tx_rdy_int;
99 unsigned int ctrl_rx_rdy_int;
100 unsigned int stat_tx_rdy;
101 unsigned int stat_rx_rdy;
102};
103
104/* Driver data, a structure for each UART port */
105struct mvebu_uart_driver_data {
106 bool is_ext;
107 struct uart_regs_layout regs;
108 struct uart_flags flags;
109};
110
111/* MVEBU UART driver structure */
112struct mvebu_uart {
113 struct uart_port *port;
114 struct clk *clk;
115 int irq[UART_IRQ_COUNT];
116 unsigned char __iomem *nb;
117 struct mvebu_uart_driver_data *data;
118};
119
120static struct mvebu_uart *to_mvuart(struct uart_port *port)
121{
122 return (struct mvebu_uart *)port->private_data;
123}
124
125#define IS_EXTENDED(port) (to_mvuart(port)->data->is_ext)
126
127#define UART_RBR(port) (to_mvuart(port)->data->regs.rbr)
128#define UART_TSH(port) (to_mvuart(port)->data->regs.tsh)
129#define UART_CTRL(port) (to_mvuart(port)->data->regs.ctrl)
130#define UART_INTR(port) (to_mvuart(port)->data->regs.intr)
131
132#define CTRL_TX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_tx_rdy_int)
133#define CTRL_RX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_rx_rdy_int)
134#define STAT_TX_RDY(port) (to_mvuart(port)->data->flags.stat_tx_rdy)
135#define STAT_RX_RDY(port) (to_mvuart(port)->data->flags.stat_rx_rdy)
136
137static struct uart_port mvebu_uart_ports[MVEBU_NR_UARTS];
138
139/* Core UART Driver Operations */
140static unsigned int mvebu_uart_tx_empty(struct uart_port *port)
141{
142 unsigned long flags;
143 unsigned int st;
144
145 spin_lock_irqsave(&port->lock, flags);
146 st = readl(port->membase + UART_STAT);
147 spin_unlock_irqrestore(&port->lock, flags);
148
149 return (st & STAT_TX_FIFO_EMP) ? TIOCSER_TEMT : 0;
150}
151
152static unsigned int mvebu_uart_get_mctrl(struct uart_port *port)
153{
154 return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
155}
156
157static void mvebu_uart_set_mctrl(struct uart_port *port,
158 unsigned int mctrl)
159{
160/*
161 * Even if we do not support configuring the modem control lines, this
162 * function must be proided to the serial core
163 */
164}
165
166static void mvebu_uart_stop_tx(struct uart_port *port)
167{
168 unsigned int ctl = readl(port->membase + UART_INTR(port));
169
170 ctl &= ~CTRL_TX_RDY_INT(port);
171 writel(ctl, port->membase + UART_INTR(port));
172}
173
174static void mvebu_uart_start_tx(struct uart_port *port)
175{
176 unsigned int ctl;
177 struct circ_buf *xmit = &port->state->xmit;
178
179 if (IS_EXTENDED(port) && !uart_circ_empty(xmit)) {
180 writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port));
181 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
182 port->icount.tx++;
183 }
184
185 ctl = readl(port->membase + UART_INTR(port));
186 ctl |= CTRL_TX_RDY_INT(port);
187 writel(ctl, port->membase + UART_INTR(port));
188}
189
190static void mvebu_uart_stop_rx(struct uart_port *port)
191{
192 unsigned int ctl;
193
194 ctl = readl(port->membase + UART_CTRL(port));
195 ctl &= ~CTRL_BRK_INT;
196 writel(ctl, port->membase + UART_CTRL(port));
197
198 ctl = readl(port->membase + UART_INTR(port));
199 ctl &= ~CTRL_RX_RDY_INT(port);
200 writel(ctl, port->membase + UART_INTR(port));
201}
202
203static void mvebu_uart_break_ctl(struct uart_port *port, int brk)
204{
205 unsigned int ctl;
206 unsigned long flags;
207
208 spin_lock_irqsave(&port->lock, flags);
209 ctl = readl(port->membase + UART_CTRL(port));
210 if (brk == -1)
211 ctl |= CTRL_SND_BRK_SEQ;
212 else
213 ctl &= ~CTRL_SND_BRK_SEQ;
214 writel(ctl, port->membase + UART_CTRL(port));
215 spin_unlock_irqrestore(&port->lock, flags);
216}
217
218static void mvebu_uart_rx_chars(struct uart_port *port, unsigned int status)
219{
220 struct tty_port *tport = &port->state->port;
221 unsigned char ch = 0;
222 char flag = 0;
223
224 do {
225 if (status & STAT_RX_RDY(port)) {
226 ch = readl(port->membase + UART_RBR(port));
227 ch &= 0xff;
228 flag = TTY_NORMAL;
229 port->icount.rx++;
230
231 if (status & STAT_PAR_ERR)
232 port->icount.parity++;
233 }
234
235 if (status & STAT_BRK_DET) {
236 port->icount.brk++;
237 status &= ~(STAT_FRM_ERR | STAT_PAR_ERR);
238 if (uart_handle_break(port))
239 goto ignore_char;
240 }
241
242 if (status & STAT_OVR_ERR)
243 port->icount.overrun++;
244
245 if (status & STAT_FRM_ERR)
246 port->icount.frame++;
247
248 if (uart_handle_sysrq_char(port, ch))
249 goto ignore_char;
250
251 if (status & port->ignore_status_mask & STAT_PAR_ERR)
252 status &= ~STAT_RX_RDY(port);
253
254 status &= port->read_status_mask;
255
256 if (status & STAT_PAR_ERR)
257 flag = TTY_PARITY;
258
259 status &= ~port->ignore_status_mask;
260
261 if (status & STAT_RX_RDY(port))
262 tty_insert_flip_char(tport, ch, flag);
263
264 if (status & STAT_BRK_DET)
265 tty_insert_flip_char(tport, 0, TTY_BREAK);
266
267 if (status & STAT_FRM_ERR)
268 tty_insert_flip_char(tport, 0, TTY_FRAME);
269
270 if (status & STAT_OVR_ERR)
271 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
272
273ignore_char:
274 status = readl(port->membase + UART_STAT);
275 } while (status & (STAT_RX_RDY(port) | STAT_BRK_DET));
276
277 tty_flip_buffer_push(tport);
278}
279
280static void mvebu_uart_tx_chars(struct uart_port *port, unsigned int status)
281{
282 struct circ_buf *xmit = &port->state->xmit;
283 unsigned int count;
284 unsigned int st;
285
286 if (port->x_char) {
287 writel(port->x_char, port->membase + UART_TSH(port));
288 port->icount.tx++;
289 port->x_char = 0;
290 return;
291 }
292
293 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
294 mvebu_uart_stop_tx(port);
295 return;
296 }
297
298 for (count = 0; count < port->fifosize; count++) {
299 writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port));
300 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
301 port->icount.tx++;
302
303 if (uart_circ_empty(xmit))
304 break;
305
306 st = readl(port->membase + UART_STAT);
307 if (st & STAT_TX_FIFO_FUL)
308 break;
309 }
310
311 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
312 uart_write_wakeup(port);
313
314 if (uart_circ_empty(xmit))
315 mvebu_uart_stop_tx(port);
316}
317
318static irqreturn_t mvebu_uart_isr(int irq, void *dev_id)
319{
320 struct uart_port *port = (struct uart_port *)dev_id;
321 unsigned int st = readl(port->membase + UART_STAT);
322
323 if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR |
324 STAT_BRK_DET))
325 mvebu_uart_rx_chars(port, st);
326
327 if (st & STAT_TX_RDY(port))
328 mvebu_uart_tx_chars(port, st);
329
330 return IRQ_HANDLED;
331}
332
333static irqreturn_t mvebu_uart_rx_isr(int irq, void *dev_id)
334{
335 struct uart_port *port = (struct uart_port *)dev_id;
336 unsigned int st = readl(port->membase + UART_STAT);
337
338 if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR |
339 STAT_BRK_DET))
340 mvebu_uart_rx_chars(port, st);
341
342 return IRQ_HANDLED;
343}
344
345static irqreturn_t mvebu_uart_tx_isr(int irq, void *dev_id)
346{
347 struct uart_port *port = (struct uart_port *)dev_id;
348 unsigned int st = readl(port->membase + UART_STAT);
349
350 if (st & STAT_TX_RDY(port))
351 mvebu_uart_tx_chars(port, st);
352
353 return IRQ_HANDLED;
354}
355
356static int mvebu_uart_startup(struct uart_port *port)
357{
358 struct mvebu_uart *mvuart = to_mvuart(port);
359 unsigned int ctl;
360 int ret;
361
362 writel(CTRL_TXFIFO_RST | CTRL_RXFIFO_RST,
363 port->membase + UART_CTRL(port));
364 udelay(1);
365
366 /* Clear the error bits of state register before IRQ request */
367 ret = readl(port->membase + UART_STAT);
368 ret |= STAT_BRK_ERR;
369 writel(ret, port->membase + UART_STAT);
370
371 writel(CTRL_BRK_INT, port->membase + UART_CTRL(port));
372
373 ctl = readl(port->membase + UART_INTR(port));
374 ctl |= CTRL_RX_RDY_INT(port);
375 writel(ctl, port->membase + UART_INTR(port));
376
377 if (!mvuart->irq[UART_TX_IRQ]) {
378 /* Old bindings with just one interrupt (UART0 only) */
379 ret = devm_request_irq(port->dev, mvuart->irq[UART_IRQ_SUM],
380 mvebu_uart_isr, port->irqflags,
381 dev_name(port->dev), port);
382 if (ret) {
383 dev_err(port->dev, "unable to request IRQ %d\n",
384 mvuart->irq[UART_IRQ_SUM]);
385 return ret;
386 }
387 } else {
388 /* New bindings with an IRQ for RX and TX (both UART) */
389 ret = devm_request_irq(port->dev, mvuart->irq[UART_RX_IRQ],
390 mvebu_uart_rx_isr, port->irqflags,
391 dev_name(port->dev), port);
392 if (ret) {
393 dev_err(port->dev, "unable to request IRQ %d\n",
394 mvuart->irq[UART_RX_IRQ]);
395 return ret;
396 }
397
398 ret = devm_request_irq(port->dev, mvuart->irq[UART_TX_IRQ],
399 mvebu_uart_tx_isr, port->irqflags,
400 dev_name(port->dev),
401 port);
402 if (ret) {
403 dev_err(port->dev, "unable to request IRQ %d\n",
404 mvuart->irq[UART_TX_IRQ]);
405 devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ],
406 port);
407 return ret;
408 }
409 }
410
411 return 0;
412}
413
414static void mvebu_uart_shutdown(struct uart_port *port)
415{
416 struct mvebu_uart *mvuart = to_mvuart(port);
417
418 writel(0, port->membase + UART_INTR(port));
419
420 if (!mvuart->irq[UART_TX_IRQ]) {
421 devm_free_irq(port->dev, mvuart->irq[UART_IRQ_SUM], port);
422 } else {
423 devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ], port);
424 devm_free_irq(port->dev, mvuart->irq[UART_TX_IRQ], port);
425 }
426}
427
428static int mvebu_uart_baud_rate_set(struct uart_port *port, unsigned int baud)
429{
430 struct mvebu_uart *mvuart = to_mvuart(port);
431 unsigned int baud_rate_div;
432 u32 brdv;
433
434 if (IS_ERR(mvuart->clk))
435 return -PTR_ERR(mvuart->clk);
436
437 /*
438 * The UART clock is divided by the value of the divisor to generate
439 * UCLK_OUT clock, which is 16 times faster than the baudrate.
440 * This prescaler can achieve all standard baudrates until 230400.
441 * Higher baudrates could be achieved for the extended UART by using the
442 * programmable oversampling stack (also called fractional divisor).
443 */
444 baud_rate_div = DIV_ROUND_UP(port->uartclk, baud * 16);
445 brdv = readl(port->membase + UART_BRDV);
446 brdv &= ~BRDV_BAUD_MASK;
447 brdv |= baud_rate_div;
448 writel(brdv, port->membase + UART_BRDV);
449
450 return 0;
451}
452
453static void mvebu_uart_set_termios(struct uart_port *port,
454 struct ktermios *termios,
455 struct ktermios *old)
456{
457 unsigned long flags;
458 unsigned int baud;
459
460 spin_lock_irqsave(&port->lock, flags);
461
462 port->read_status_mask = STAT_RX_RDY(port) | STAT_OVR_ERR |
463 STAT_TX_RDY(port) | STAT_TX_FIFO_FUL;
464
465 if (termios->c_iflag & INPCK)
466 port->read_status_mask |= STAT_FRM_ERR | STAT_PAR_ERR;
467
468 port->ignore_status_mask = 0;
469 if (termios->c_iflag & IGNPAR)
470 port->ignore_status_mask |=
471 STAT_FRM_ERR | STAT_PAR_ERR | STAT_OVR_ERR;
472
473 if ((termios->c_cflag & CREAD) == 0)
474 port->ignore_status_mask |= STAT_RX_RDY(port) | STAT_BRK_ERR;
475
476 /*
477 * Maximum achievable frequency with simple baudrate divisor is 230400.
478 * Since the error per bit frame would be of more than 15%, achieving
479 * higher frequencies would require to implement the fractional divisor
480 * feature.
481 */
482 baud = uart_get_baud_rate(port, termios, old, 0, 230400);
483 if (mvebu_uart_baud_rate_set(port, baud)) {
484 /* No clock available, baudrate cannot be changed */
485 if (old)
486 baud = uart_get_baud_rate(port, old, NULL, 0, 230400);
487 } else {
488 tty_termios_encode_baud_rate(termios, baud, baud);
489 uart_update_timeout(port, termios->c_cflag, baud);
490 }
491
492 /* Only the following flag changes are supported */
493 if (old) {
494 termios->c_iflag &= INPCK | IGNPAR;
495 termios->c_iflag |= old->c_iflag & ~(INPCK | IGNPAR);
496 termios->c_cflag &= CREAD | CBAUD;
497 termios->c_cflag |= old->c_cflag & ~(CREAD | CBAUD);
498 }
499
500 spin_unlock_irqrestore(&port->lock, flags);
501}
502
503static const char *mvebu_uart_type(struct uart_port *port)
504{
505 return MVEBU_UART_TYPE;
506}
507
508static void mvebu_uart_release_port(struct uart_port *port)
509{
510 /* Nothing to do here */
511}
512
513static int mvebu_uart_request_port(struct uart_port *port)
514{
515 return 0;
516}
517
518#ifdef CONFIG_CONSOLE_POLL
519static int mvebu_uart_get_poll_char(struct uart_port *port)
520{
521 unsigned int st = readl(port->membase + UART_STAT);
522
523 if (!(st & STAT_RX_RDY(port)))
524 return NO_POLL_CHAR;
525
526 return readl(port->membase + UART_RBR(port));
527}
528
529static void mvebu_uart_put_poll_char(struct uart_port *port, unsigned char c)
530{
531 unsigned int st;
532
533 for (;;) {
534 st = readl(port->membase + UART_STAT);
535
536 if (!(st & STAT_TX_FIFO_FUL))
537 break;
538
539 udelay(1);
540 }
541
542 writel(c, port->membase + UART_TSH(port));
543}
544#endif
545
546static const struct uart_ops mvebu_uart_ops = {
547 .tx_empty = mvebu_uart_tx_empty,
548 .set_mctrl = mvebu_uart_set_mctrl,
549 .get_mctrl = mvebu_uart_get_mctrl,
550 .stop_tx = mvebu_uart_stop_tx,
551 .start_tx = mvebu_uart_start_tx,
552 .stop_rx = mvebu_uart_stop_rx,
553 .break_ctl = mvebu_uart_break_ctl,
554 .startup = mvebu_uart_startup,
555 .shutdown = mvebu_uart_shutdown,
556 .set_termios = mvebu_uart_set_termios,
557 .type = mvebu_uart_type,
558 .release_port = mvebu_uart_release_port,
559 .request_port = mvebu_uart_request_port,
560#ifdef CONFIG_CONSOLE_POLL
561 .poll_get_char = mvebu_uart_get_poll_char,
562 .poll_put_char = mvebu_uart_put_poll_char,
563#endif
564};
565
566/* Console Driver Operations */
567
568#ifdef CONFIG_SERIAL_MVEBU_CONSOLE
569/* Early Console */
570static void mvebu_uart_putc(struct uart_port *port, int c)
571{
572 unsigned int st;
573
574 for (;;) {
575 st = readl(port->membase + UART_STAT);
576 if (!(st & STAT_TX_FIFO_FUL))
577 break;
578 }
579
580 /* At early stage, DT is not parsed yet, only use UART0 */
581 writel(c, port->membase + UART_STD_TSH);
582
583 for (;;) {
584 st = readl(port->membase + UART_STAT);
585 if (st & STAT_TX_FIFO_EMP)
586 break;
587 }
588}
589
590static void mvebu_uart_putc_early_write(struct console *con,
591 const char *s,
592 unsigned n)
593{
594 struct earlycon_device *dev = con->data;
595
596 uart_console_write(&dev->port, s, n, mvebu_uart_putc);
597}
598
599static int __init
600mvebu_uart_early_console_setup(struct earlycon_device *device,
601 const char *opt)
602{
603 if (!device->port.membase)
604 return -ENODEV;
605
606 device->con->write = mvebu_uart_putc_early_write;
607
608 return 0;
609}
610
611EARLYCON_DECLARE(ar3700_uart, mvebu_uart_early_console_setup);
612OF_EARLYCON_DECLARE(ar3700_uart, "marvell,armada-3700-uart",
613 mvebu_uart_early_console_setup);
614
615static void wait_for_xmitr(struct uart_port *port)
616{
617 u32 val;
618
619 readl_poll_timeout_atomic(port->membase + UART_STAT, val,
620 (val & STAT_TX_RDY(port)), 1, 10000);
621}
622
623static void mvebu_uart_console_putchar(struct uart_port *port, int ch)
624{
625 wait_for_xmitr(port);
626 writel(ch, port->membase + UART_TSH(port));
627}
628
629static void mvebu_uart_console_write(struct console *co, const char *s,
630 unsigned int count)
631{
632 struct uart_port *port = &mvebu_uart_ports[co->index];
633 unsigned long flags;
634 unsigned int ier, intr, ctl;
635 int locked = 1;
636
637 if (oops_in_progress)
638 locked = spin_trylock_irqsave(&port->lock, flags);
639 else
640 spin_lock_irqsave(&port->lock, flags);
641
642 ier = readl(port->membase + UART_CTRL(port)) & CTRL_BRK_INT;
643 intr = readl(port->membase + UART_INTR(port)) &
644 (CTRL_RX_RDY_INT(port) | CTRL_TX_RDY_INT(port));
645 writel(0, port->membase + UART_CTRL(port));
646 writel(0, port->membase + UART_INTR(port));
647
648 uart_console_write(port, s, count, mvebu_uart_console_putchar);
649
650 wait_for_xmitr(port);
651
652 if (ier)
653 writel(ier, port->membase + UART_CTRL(port));
654
655 if (intr) {
656 ctl = intr | readl(port->membase + UART_INTR(port));
657 writel(ctl, port->membase + UART_INTR(port));
658 }
659
660 if (locked)
661 spin_unlock_irqrestore(&port->lock, flags);
662}
663
664static int mvebu_uart_console_setup(struct console *co, char *options)
665{
666 struct uart_port *port;
667 int baud = 9600;
668 int bits = 8;
669 int parity = 'n';
670 int flow = 'n';
671
672 if (co->index < 0 || co->index >= MVEBU_NR_UARTS)
673 return -EINVAL;
674
675 port = &mvebu_uart_ports[co->index];
676
677 if (!port->mapbase || !port->membase) {
678 pr_debug("console on ttyMV%i not present\n", co->index);
679 return -ENODEV;
680 }
681
682 if (options)
683 uart_parse_options(options, &baud, &parity, &bits, &flow);
684
685 return uart_set_options(port, co, baud, parity, bits, flow);
686}
687
688static struct uart_driver mvebu_uart_driver;
689
690static struct console mvebu_uart_console = {
691 .name = "ttyMV",
692 .write = mvebu_uart_console_write,
693 .device = uart_console_device,
694 .setup = mvebu_uart_console_setup,
695 .flags = CON_PRINTBUFFER,
696 .index = -1,
697 .data = &mvebu_uart_driver,
698};
699
700static int __init mvebu_uart_console_init(void)
701{
702 register_console(&mvebu_uart_console);
703 return 0;
704}
705
706console_initcall(mvebu_uart_console_init);
707
708
709#endif /* CONFIG_SERIAL_MVEBU_CONSOLE */
710
711static struct uart_driver mvebu_uart_driver = {
712 .owner = THIS_MODULE,
713 .driver_name = DRIVER_NAME,
714 .dev_name = "ttyMV",
715 .nr = MVEBU_NR_UARTS,
716#ifdef CONFIG_SERIAL_MVEBU_CONSOLE
717 .cons = &mvebu_uart_console,
718#endif
719};
720
721static const struct of_device_id mvebu_uart_of_match[];
722
723/* Counter to keep track of each UART port id when not using CONFIG_OF */
724static int uart_num_counter;
725
726static int mvebu_uart_probe(struct platform_device *pdev)
727{
728 struct resource *reg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
729 const struct of_device_id *match = of_match_device(mvebu_uart_of_match,
730 &pdev->dev);
731 struct uart_port *port;
732 struct mvebu_uart *mvuart;
733 int ret, id, irq;
734
735 if (!reg) {
736 dev_err(&pdev->dev, "no registers defined\n");
737 return -EINVAL;
738 }
739
740 /* Assume that all UART ports have a DT alias or none has */
741 id = of_alias_get_id(pdev->dev.of_node, "serial");
742 if (!pdev->dev.of_node || id < 0)
743 pdev->id = uart_num_counter++;
744 else
745 pdev->id = id;
746
747 if (pdev->id >= MVEBU_NR_UARTS) {
748 dev_err(&pdev->dev, "cannot have more than %d UART ports\n",
749 MVEBU_NR_UARTS);
750 return -EINVAL;
751 }
752
753 port = &mvebu_uart_ports[pdev->id];
754
755 spin_lock_init(&port->lock);
756
757 port->dev = &pdev->dev;
758 port->type = PORT_MVEBU;
759 port->ops = &mvebu_uart_ops;
760 port->regshift = 0;
761
762 port->fifosize = 32;
763 port->iotype = UPIO_MEM32;
764 port->flags = UPF_FIXED_PORT;
765 port->line = pdev->id;
766
767 /*
768 * IRQ number is not stored in this structure because we may have two of
769 * them per port (RX and TX). Instead, use the driver UART structure
770 * array so called ->irq[].
771 */
772 port->irq = 0;
773 port->irqflags = 0;
774 port->mapbase = reg->start;
775
776 port->membase = devm_ioremap_resource(&pdev->dev, reg);
777 if (IS_ERR(port->membase))
778 return -PTR_ERR(port->membase);
779
780 mvuart = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_uart),
781 GFP_KERNEL);
782 if (!mvuart)
783 return -ENOMEM;
784
785 /* Get controller data depending on the compatible string */
786 mvuart->data = (struct mvebu_uart_driver_data *)match->data;
787 mvuart->port = port;
788
789 port->private_data = mvuart;
790 platform_set_drvdata(pdev, mvuart);
791
792 /* Get fixed clock frequency */
793 mvuart->clk = devm_clk_get(&pdev->dev, NULL);
794 if (IS_ERR(mvuart->clk)) {
795 if (PTR_ERR(mvuart->clk) == -EPROBE_DEFER)
796 return PTR_ERR(mvuart->clk);
797
798 if (IS_EXTENDED(port)) {
799 dev_err(&pdev->dev, "unable to get UART clock\n");
800 return PTR_ERR(mvuart->clk);
801 }
802 } else {
803 if (!clk_prepare_enable(mvuart->clk))
804 port->uartclk = clk_get_rate(mvuart->clk);
805 }
806
807 /* Manage interrupts */
808 if (platform_irq_count(pdev) == 1) {
809 /* Old bindings: no name on the single unamed UART0 IRQ */
810 irq = platform_get_irq(pdev, 0);
811 if (irq < 0) {
812 dev_err(&pdev->dev, "unable to get UART IRQ\n");
813 return irq;
814 }
815
816 mvuart->irq[UART_IRQ_SUM] = irq;
817 } else {
818 /*
819 * New bindings: named interrupts (RX, TX) for both UARTS,
820 * only make use of uart-rx and uart-tx interrupts, do not use
821 * uart-sum of UART0 port.
822 */
823 irq = platform_get_irq_byname(pdev, "uart-rx");
824 if (irq < 0) {
825 dev_err(&pdev->dev, "unable to get 'uart-rx' IRQ\n");
826 return irq;
827 }
828
829 mvuart->irq[UART_RX_IRQ] = irq;
830
831 irq = platform_get_irq_byname(pdev, "uart-tx");
832 if (irq < 0) {
833 dev_err(&pdev->dev, "unable to get 'uart-tx' IRQ\n");
834 return irq;
835 }
836
837 mvuart->irq[UART_TX_IRQ] = irq;
838 }
839
840 /* UART Soft Reset*/
841 writel(CTRL_SOFT_RST, port->membase + UART_CTRL(port));
842 udelay(1);
843 writel(0, port->membase + UART_CTRL(port));
844
845 ret = uart_add_one_port(&mvebu_uart_driver, port);
846 if (ret)
847 return ret;
848 return 0;
849}
850
851static struct mvebu_uart_driver_data uart_std_driver_data = {
852 .is_ext = false,
853 .regs.rbr = UART_STD_RBR,
854 .regs.tsh = UART_STD_TSH,
855 .regs.ctrl = UART_STD_CTRL1,
856 .regs.intr = UART_STD_CTRL2,
857 .flags.ctrl_tx_rdy_int = CTRL_STD_TX_RDY_INT,
858 .flags.ctrl_rx_rdy_int = CTRL_STD_RX_RDY_INT,
859 .flags.stat_tx_rdy = STAT_STD_TX_RDY,
860 .flags.stat_rx_rdy = STAT_STD_RX_RDY,
861};
862
863static struct mvebu_uart_driver_data uart_ext_driver_data = {
864 .is_ext = true,
865 .regs.rbr = UART_EXT_RBR,
866 .regs.tsh = UART_EXT_TSH,
867 .regs.ctrl = UART_EXT_CTRL1,
868 .regs.intr = UART_EXT_CTRL2,
869 .flags.ctrl_tx_rdy_int = CTRL_EXT_TX_RDY_INT,
870 .flags.ctrl_rx_rdy_int = CTRL_EXT_RX_RDY_INT,
871 .flags.stat_tx_rdy = STAT_EXT_TX_RDY,
872 .flags.stat_rx_rdy = STAT_EXT_RX_RDY,
873};
874
875/* Match table for of_platform binding */
876static const struct of_device_id mvebu_uart_of_match[] = {
877 {
878 .compatible = "marvell,armada-3700-uart",
879 .data = (void *)&uart_std_driver_data,
880 },
881 {
882 .compatible = "marvell,armada-3700-uart-ext",
883 .data = (void *)&uart_ext_driver_data,
884 },
885 {}
886};
887
888static struct platform_driver mvebu_uart_platform_driver = {
889 .probe = mvebu_uart_probe,
890 .driver = {
891 .name = "mvebu-uart",
892 .of_match_table = of_match_ptr(mvebu_uart_of_match),
893 .suppress_bind_attrs = true,
894 },
895};
896
897static int __init mvebu_uart_init(void)
898{
899 int ret;
900
901 ret = uart_register_driver(&mvebu_uart_driver);
902 if (ret)
903 return ret;
904
905 ret = platform_driver_register(&mvebu_uart_platform_driver);
906 if (ret)
907 uart_unregister_driver(&mvebu_uart_driver);
908
909 return ret;
910}
911arch_initcall(mvebu_uart_init);