blob: 3d966cfc9a38cba524a5a13383f4c6bda4a62328 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/drivers/char/amba.c
3 *
4 * Driver for AMBA serial ports
5 *
6 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
7 *
8 * Copyright 1999 ARM Limited
9 * Copyright (C) 2000 Deep Blue Solutions Ltd.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 *
25 * $Id: amba.c,v 1.41 2002/07/28 10:03:27 rmk Exp $
26 *
27 * This is a generic driver for ARM AMBA-type serial ports. They
28 * have a lot of 16550-like features, but are not register compatible.
29 * Note that although they do have CTS, DCD and DSR inputs, they do
30 * not have an RI input, nor do they have DTR or RTS outputs. If
31 * required, these have to be supplied via some other means (eg, GPIO)
32 * and hooked into this driver.
33 */
34#include <linux/config.h>
35
36#if defined(CONFIG_SERIAL_AMBA_PL011_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
37#define SUPPORT_SYSRQ
38#endif
39
40#include <linux/module.h>
41#include <linux/ioport.h>
42#include <linux/init.h>
43#include <linux/console.h>
44#include <linux/sysrq.h>
45#include <linux/device.h>
46#include <linux/tty.h>
47#include <linux/tty_flip.h>
48#include <linux/serial_core.h>
49#include <linux/serial.h>
Russell Kinga62c80e2006-01-07 13:52:45 +000050#include <linux/amba/bus.h>
51#include <linux/amba/serial.h>
Russell Kingf8ce2542006-01-07 16:15:52 +000052#include <linux/clk.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54#include <asm/io.h>
Russell Kingc6b8fda2005-10-28 14:05:16 +010055#include <asm/sizes.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57#define UART_NR 14
58
59#define SERIAL_AMBA_MAJOR 204
60#define SERIAL_AMBA_MINOR 64
61#define SERIAL_AMBA_NR UART_NR
62
63#define AMBA_ISR_PASS_LIMIT 256
64
Russell Kingb63d4f02005-11-19 11:10:35 +000065#define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE)
66#define UART_DUMMY_DR_RX (1 << 16)
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
68/*
69 * We wrap our port structure around the generic uart_port.
70 */
71struct uart_amba_port {
72 struct uart_port port;
73 struct clk *clk;
74 unsigned int im; /* interrupt mask */
75 unsigned int old_status;
76};
77
Russell Kingb129a8c2005-08-31 10:12:14 +010078static void pl011_stop_tx(struct uart_port *port)
Linus Torvalds1da177e2005-04-16 15:20:36 -070079{
80 struct uart_amba_port *uap = (struct uart_amba_port *)port;
81
82 uap->im &= ~UART011_TXIM;
83 writew(uap->im, uap->port.membase + UART011_IMSC);
84}
85
Russell Kingb129a8c2005-08-31 10:12:14 +010086static void pl011_start_tx(struct uart_port *port)
Linus Torvalds1da177e2005-04-16 15:20:36 -070087{
88 struct uart_amba_port *uap = (struct uart_amba_port *)port;
89
90 uap->im |= UART011_TXIM;
91 writew(uap->im, uap->port.membase + UART011_IMSC);
92}
93
94static void pl011_stop_rx(struct uart_port *port)
95{
96 struct uart_amba_port *uap = (struct uart_amba_port *)port;
97
98 uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
99 UART011_PEIM|UART011_BEIM|UART011_OEIM);
100 writew(uap->im, uap->port.membase + UART011_IMSC);
101}
102
103static void pl011_enable_ms(struct uart_port *port)
104{
105 struct uart_amba_port *uap = (struct uart_amba_port *)port;
106
107 uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
108 writew(uap->im, uap->port.membase + UART011_IMSC);
109}
110
111static void
112#ifdef SUPPORT_SYSRQ
113pl011_rx_chars(struct uart_amba_port *uap, struct pt_regs *regs)
114#else
115pl011_rx_chars(struct uart_amba_port *uap)
116#endif
117{
118 struct tty_struct *tty = uap->port.info->tty;
Russell Kingb63d4f02005-11-19 11:10:35 +0000119 unsigned int status, ch, flag, max_count = 256;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120
121 status = readw(uap->port.membase + UART01x_FR);
122 while ((status & UART01x_FR_RXFE) == 0 && max_count--) {
Russell Kingb63d4f02005-11-19 11:10:35 +0000123 ch = readw(uap->port.membase + UART01x_DR) | UART_DUMMY_DR_RX;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 flag = TTY_NORMAL;
125 uap->port.icount.rx++;
126
127 /*
128 * Note that the error handling code is
129 * out of the main execution path
130 */
Russell Kingb63d4f02005-11-19 11:10:35 +0000131 if (unlikely(ch & UART_DR_ERROR)) {
132 if (ch & UART011_DR_BE) {
133 ch &= ~(UART011_DR_FE | UART011_DR_PE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 uap->port.icount.brk++;
135 if (uart_handle_break(&uap->port))
136 goto ignore_char;
Russell Kingb63d4f02005-11-19 11:10:35 +0000137 } else if (ch & UART011_DR_PE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138 uap->port.icount.parity++;
Russell Kingb63d4f02005-11-19 11:10:35 +0000139 else if (ch & UART011_DR_FE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 uap->port.icount.frame++;
Russell Kingb63d4f02005-11-19 11:10:35 +0000141 if (ch & UART011_DR_OE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 uap->port.icount.overrun++;
143
Russell Kingb63d4f02005-11-19 11:10:35 +0000144 ch &= uap->port.read_status_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145
Russell Kingb63d4f02005-11-19 11:10:35 +0000146 if (ch & UART011_DR_BE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 flag = TTY_BREAK;
Russell Kingb63d4f02005-11-19 11:10:35 +0000148 else if (ch & UART011_DR_PE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 flag = TTY_PARITY;
Russell Kingb63d4f02005-11-19 11:10:35 +0000150 else if (ch & UART011_DR_FE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 flag = TTY_FRAME;
152 }
153
Russell Kinga710ce02005-12-27 11:10:34 +0000154 if (uart_handle_sysrq_char(&uap->port, ch & 255, regs))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 goto ignore_char;
156
Russell Kingb63d4f02005-11-19 11:10:35 +0000157 uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag);
Russell King05ab3012005-05-09 23:21:59 +0100158
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 ignore_char:
160 status = readw(uap->port.membase + UART01x_FR);
161 }
162 tty_flip_buffer_push(tty);
163 return;
164}
165
166static void pl011_tx_chars(struct uart_amba_port *uap)
167{
168 struct circ_buf *xmit = &uap->port.info->xmit;
169 int count;
170
171 if (uap->port.x_char) {
172 writew(uap->port.x_char, uap->port.membase + UART01x_DR);
173 uap->port.icount.tx++;
174 uap->port.x_char = 0;
175 return;
176 }
177 if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
Russell Kingb129a8c2005-08-31 10:12:14 +0100178 pl011_stop_tx(&uap->port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179 return;
180 }
181
182 count = uap->port.fifosize >> 1;
183 do {
184 writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
185 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
186 uap->port.icount.tx++;
187 if (uart_circ_empty(xmit))
188 break;
189 } while (--count > 0);
190
191 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
192 uart_write_wakeup(&uap->port);
193
194 if (uart_circ_empty(xmit))
Russell Kingb129a8c2005-08-31 10:12:14 +0100195 pl011_stop_tx(&uap->port);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196}
197
198static void pl011_modem_status(struct uart_amba_port *uap)
199{
200 unsigned int status, delta;
201
202 status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
203
204 delta = status ^ uap->old_status;
205 uap->old_status = status;
206
207 if (!delta)
208 return;
209
210 if (delta & UART01x_FR_DCD)
211 uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
212
213 if (delta & UART01x_FR_DSR)
214 uap->port.icount.dsr++;
215
216 if (delta & UART01x_FR_CTS)
217 uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
218
219 wake_up_interruptible(&uap->port.info->delta_msr_wait);
220}
221
222static irqreturn_t pl011_int(int irq, void *dev_id, struct pt_regs *regs)
223{
224 struct uart_amba_port *uap = dev_id;
225 unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
226 int handled = 0;
227
228 spin_lock(&uap->port.lock);
229
230 status = readw(uap->port.membase + UART011_MIS);
231 if (status) {
232 do {
233 writew(status & ~(UART011_TXIS|UART011_RTIS|
234 UART011_RXIS),
235 uap->port.membase + UART011_ICR);
236
237 if (status & (UART011_RTIS|UART011_RXIS))
238#ifdef SUPPORT_SYSRQ
239 pl011_rx_chars(uap, regs);
240#else
241 pl011_rx_chars(uap);
242#endif
243 if (status & (UART011_DSRMIS|UART011_DCDMIS|
244 UART011_CTSMIS|UART011_RIMIS))
245 pl011_modem_status(uap);
246 if (status & UART011_TXIS)
247 pl011_tx_chars(uap);
248
249 if (pass_counter-- == 0)
250 break;
251
252 status = readw(uap->port.membase + UART011_MIS);
253 } while (status != 0);
254 handled = 1;
255 }
256
257 spin_unlock(&uap->port.lock);
258
259 return IRQ_RETVAL(handled);
260}
261
262static unsigned int pl01x_tx_empty(struct uart_port *port)
263{
264 struct uart_amba_port *uap = (struct uart_amba_port *)port;
265 unsigned int status = readw(uap->port.membase + UART01x_FR);
266 return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT;
267}
268
269static unsigned int pl01x_get_mctrl(struct uart_port *port)
270{
271 struct uart_amba_port *uap = (struct uart_amba_port *)port;
272 unsigned int result = 0;
273 unsigned int status = readw(uap->port.membase + UART01x_FR);
274
275#define BIT(uartbit, tiocmbit) \
276 if (status & uartbit) \
277 result |= tiocmbit
278
279 BIT(UART01x_FR_DCD, TIOCM_CAR);
280 BIT(UART01x_FR_DSR, TIOCM_DSR);
281 BIT(UART01x_FR_CTS, TIOCM_CTS);
282 BIT(UART011_FR_RI, TIOCM_RNG);
283#undef BIT
284 return result;
285}
286
287static void pl011_set_mctrl(struct uart_port *port, unsigned int mctrl)
288{
289 struct uart_amba_port *uap = (struct uart_amba_port *)port;
290 unsigned int cr;
291
292 cr = readw(uap->port.membase + UART011_CR);
293
294#define BIT(tiocmbit, uartbit) \
295 if (mctrl & tiocmbit) \
296 cr |= uartbit; \
297 else \
298 cr &= ~uartbit
299
300 BIT(TIOCM_RTS, UART011_CR_RTS);
301 BIT(TIOCM_DTR, UART011_CR_DTR);
302 BIT(TIOCM_OUT1, UART011_CR_OUT1);
303 BIT(TIOCM_OUT2, UART011_CR_OUT2);
304 BIT(TIOCM_LOOP, UART011_CR_LBE);
305#undef BIT
306
307 writew(cr, uap->port.membase + UART011_CR);
308}
309
310static void pl011_break_ctl(struct uart_port *port, int break_state)
311{
312 struct uart_amba_port *uap = (struct uart_amba_port *)port;
313 unsigned long flags;
314 unsigned int lcr_h;
315
316 spin_lock_irqsave(&uap->port.lock, flags);
317 lcr_h = readw(uap->port.membase + UART011_LCRH);
318 if (break_state == -1)
319 lcr_h |= UART01x_LCRH_BRK;
320 else
321 lcr_h &= ~UART01x_LCRH_BRK;
322 writew(lcr_h, uap->port.membase + UART011_LCRH);
323 spin_unlock_irqrestore(&uap->port.lock, flags);
324}
325
326static int pl011_startup(struct uart_port *port)
327{
328 struct uart_amba_port *uap = (struct uart_amba_port *)port;
329 unsigned int cr;
330 int retval;
331
332 /*
333 * Try to enable the clock producer.
334 */
335 retval = clk_enable(uap->clk);
336 if (retval)
337 goto out;
338
339 uap->port.uartclk = clk_get_rate(uap->clk);
340
341 /*
342 * Allocate the IRQ
343 */
344 retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap);
345 if (retval)
346 goto clk_dis;
347
348 writew(UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
349 uap->port.membase + UART011_IFLS);
350
351 /*
352 * Provoke TX FIFO interrupt into asserting.
353 */
354 cr = UART01x_CR_UARTEN | UART011_CR_TXE | UART011_CR_LBE;
355 writew(cr, uap->port.membase + UART011_CR);
356 writew(0, uap->port.membase + UART011_FBRD);
357 writew(1, uap->port.membase + UART011_IBRD);
358 writew(0, uap->port.membase + UART011_LCRH);
359 writew(0, uap->port.membase + UART01x_DR);
360 while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
361 barrier();
362
363 cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
364 writew(cr, uap->port.membase + UART011_CR);
365
366 /*
367 * initialise the old status of the modem signals
368 */
369 uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
370
371 /*
372 * Finally, enable interrupts
373 */
374 spin_lock_irq(&uap->port.lock);
375 uap->im = UART011_RXIM | UART011_RTIM;
376 writew(uap->im, uap->port.membase + UART011_IMSC);
377 spin_unlock_irq(&uap->port.lock);
378
379 return 0;
380
381 clk_dis:
382 clk_disable(uap->clk);
383 out:
384 return retval;
385}
386
387static void pl011_shutdown(struct uart_port *port)
388{
389 struct uart_amba_port *uap = (struct uart_amba_port *)port;
390 unsigned long val;
391
392 /*
393 * disable all interrupts
394 */
395 spin_lock_irq(&uap->port.lock);
396 uap->im = 0;
397 writew(uap->im, uap->port.membase + UART011_IMSC);
398 writew(0xffff, uap->port.membase + UART011_ICR);
399 spin_unlock_irq(&uap->port.lock);
400
401 /*
402 * Free the interrupt
403 */
404 free_irq(uap->port.irq, uap);
405
406 /*
407 * disable the port
408 */
409 writew(UART01x_CR_UARTEN | UART011_CR_TXE, uap->port.membase + UART011_CR);
410
411 /*
412 * disable break condition and fifos
413 */
414 val = readw(uap->port.membase + UART011_LCRH);
415 val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
416 writew(val, uap->port.membase + UART011_LCRH);
417
418 /*
419 * Shut down the clock producer
420 */
421 clk_disable(uap->clk);
422}
423
424static void
425pl011_set_termios(struct uart_port *port, struct termios *termios,
426 struct termios *old)
427{
428 unsigned int lcr_h, old_cr;
429 unsigned long flags;
430 unsigned int baud, quot;
431
432 /*
433 * Ask the core to calculate the divisor for us.
434 */
435 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
436 quot = port->uartclk * 4 / baud;
437
438 switch (termios->c_cflag & CSIZE) {
439 case CS5:
440 lcr_h = UART01x_LCRH_WLEN_5;
441 break;
442 case CS6:
443 lcr_h = UART01x_LCRH_WLEN_6;
444 break;
445 case CS7:
446 lcr_h = UART01x_LCRH_WLEN_7;
447 break;
448 default: // CS8
449 lcr_h = UART01x_LCRH_WLEN_8;
450 break;
451 }
452 if (termios->c_cflag & CSTOPB)
453 lcr_h |= UART01x_LCRH_STP2;
454 if (termios->c_cflag & PARENB) {
455 lcr_h |= UART01x_LCRH_PEN;
456 if (!(termios->c_cflag & PARODD))
457 lcr_h |= UART01x_LCRH_EPS;
458 }
459 if (port->fifosize > 1)
460 lcr_h |= UART01x_LCRH_FEN;
461
462 spin_lock_irqsave(&port->lock, flags);
463
464 /*
465 * Update the per-port timeout.
466 */
467 uart_update_timeout(port, termios->c_cflag, baud);
468
Russell Kingb63d4f02005-11-19 11:10:35 +0000469 port->read_status_mask = UART011_DR_OE | 255;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 if (termios->c_iflag & INPCK)
Russell Kingb63d4f02005-11-19 11:10:35 +0000471 port->read_status_mask |= UART011_DR_FE | UART011_DR_PE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 if (termios->c_iflag & (BRKINT | PARMRK))
Russell Kingb63d4f02005-11-19 11:10:35 +0000473 port->read_status_mask |= UART011_DR_BE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474
475 /*
476 * Characters to ignore
477 */
478 port->ignore_status_mask = 0;
479 if (termios->c_iflag & IGNPAR)
Russell Kingb63d4f02005-11-19 11:10:35 +0000480 port->ignore_status_mask |= UART011_DR_FE | UART011_DR_PE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 if (termios->c_iflag & IGNBRK) {
Russell Kingb63d4f02005-11-19 11:10:35 +0000482 port->ignore_status_mask |= UART011_DR_BE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483 /*
484 * If we're ignoring parity and break indicators,
485 * ignore overruns too (for real raw support).
486 */
487 if (termios->c_iflag & IGNPAR)
Russell Kingb63d4f02005-11-19 11:10:35 +0000488 port->ignore_status_mask |= UART011_DR_OE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 }
490
491 /*
492 * Ignore all characters if CREAD is not set.
493 */
494 if ((termios->c_cflag & CREAD) == 0)
Russell Kingb63d4f02005-11-19 11:10:35 +0000495 port->ignore_status_mask |= UART_DUMMY_DR_RX;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496
497 if (UART_ENABLE_MS(port, termios->c_cflag))
498 pl011_enable_ms(port);
499
500 /* first, disable everything */
501 old_cr = readw(port->membase + UART011_CR);
502 writew(0, port->membase + UART011_CR);
503
504 /* Set baud rate */
505 writew(quot & 0x3f, port->membase + UART011_FBRD);
506 writew(quot >> 6, port->membase + UART011_IBRD);
507
508 /*
509 * ----------v----------v----------v----------v-----
510 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
511 * ----------^----------^----------^----------^-----
512 */
513 writew(lcr_h, port->membase + UART011_LCRH);
514 writew(old_cr, port->membase + UART011_CR);
515
516 spin_unlock_irqrestore(&port->lock, flags);
517}
518
519static const char *pl011_type(struct uart_port *port)
520{
521 return port->type == PORT_AMBA ? "AMBA/PL011" : NULL;
522}
523
524/*
525 * Release the memory region(s) being used by 'port'
526 */
527static void pl010_release_port(struct uart_port *port)
528{
529 release_mem_region(port->mapbase, SZ_4K);
530}
531
532/*
533 * Request the memory region(s) being used by 'port'
534 */
535static int pl010_request_port(struct uart_port *port)
536{
537 return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
538 != NULL ? 0 : -EBUSY;
539}
540
541/*
542 * Configure/autoconfigure the port.
543 */
544static void pl010_config_port(struct uart_port *port, int flags)
545{
546 if (flags & UART_CONFIG_TYPE) {
547 port->type = PORT_AMBA;
548 pl010_request_port(port);
549 }
550}
551
552/*
553 * verify the new serial_struct (for TIOCSSERIAL).
554 */
555static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
556{
557 int ret = 0;
558 if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
559 ret = -EINVAL;
560 if (ser->irq < 0 || ser->irq >= NR_IRQS)
561 ret = -EINVAL;
562 if (ser->baud_base < 9600)
563 ret = -EINVAL;
564 return ret;
565}
566
567static struct uart_ops amba_pl011_pops = {
568 .tx_empty = pl01x_tx_empty,
569 .set_mctrl = pl011_set_mctrl,
570 .get_mctrl = pl01x_get_mctrl,
571 .stop_tx = pl011_stop_tx,
572 .start_tx = pl011_start_tx,
573 .stop_rx = pl011_stop_rx,
574 .enable_ms = pl011_enable_ms,
575 .break_ctl = pl011_break_ctl,
576 .startup = pl011_startup,
577 .shutdown = pl011_shutdown,
578 .set_termios = pl011_set_termios,
579 .type = pl011_type,
580 .release_port = pl010_release_port,
581 .request_port = pl010_request_port,
582 .config_port = pl010_config_port,
583 .verify_port = pl010_verify_port,
584};
585
586static struct uart_amba_port *amba_ports[UART_NR];
587
588#ifdef CONFIG_SERIAL_AMBA_PL011_CONSOLE
589
Russell Kingd3587882006-03-20 20:00:09 +0000590static void pl011_console_putchar(struct uart_port *port, int ch)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591{
Russell Kingd3587882006-03-20 20:00:09 +0000592 struct uart_amba_port *uap = (struct uart_amba_port *)port;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593
Russell Kingd3587882006-03-20 20:00:09 +0000594 while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF)
595 barrier();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 writew(ch, uap->port.membase + UART01x_DR);
597}
598
599static void
600pl011_console_write(struct console *co, const char *s, unsigned int count)
601{
602 struct uart_amba_port *uap = amba_ports[co->index];
603 unsigned int status, old_cr, new_cr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604
605 clk_enable(uap->clk);
606
607 /*
608 * First save the CR then disable the interrupts
609 */
610 old_cr = readw(uap->port.membase + UART011_CR);
611 new_cr = old_cr & ~UART011_CR_CTSEN;
612 new_cr |= UART01x_CR_UARTEN | UART011_CR_TXE;
613 writew(new_cr, uap->port.membase + UART011_CR);
614
Russell Kingd3587882006-03-20 20:00:09 +0000615 uart_console_write(&uap->port, s, count, pl011_console_putchar);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616
617 /*
618 * Finally, wait for transmitter to become empty
619 * and restore the TCR
620 */
621 do {
622 status = readw(uap->port.membase + UART01x_FR);
623 } while (status & UART01x_FR_BUSY);
624 writew(old_cr, uap->port.membase + UART011_CR);
625
626 clk_disable(uap->clk);
627}
628
629static void __init
630pl011_console_get_options(struct uart_amba_port *uap, int *baud,
631 int *parity, int *bits)
632{
633 if (readw(uap->port.membase + UART011_CR) & UART01x_CR_UARTEN) {
634 unsigned int lcr_h, ibrd, fbrd;
635
636 lcr_h = readw(uap->port.membase + UART011_LCRH);
637
638 *parity = 'n';
639 if (lcr_h & UART01x_LCRH_PEN) {
640 if (lcr_h & UART01x_LCRH_EPS)
641 *parity = 'e';
642 else
643 *parity = 'o';
644 }
645
646 if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
647 *bits = 7;
648 else
649 *bits = 8;
650
651 ibrd = readw(uap->port.membase + UART011_IBRD);
652 fbrd = readw(uap->port.membase + UART011_FBRD);
653
654 *baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
655 }
656}
657
658static int __init pl011_console_setup(struct console *co, char *options)
659{
660 struct uart_amba_port *uap;
661 int baud = 38400;
662 int bits = 8;
663 int parity = 'n';
664 int flow = 'n';
665
666 /*
667 * Check whether an invalid uart number has been specified, and
668 * if so, search for the first available port that does have
669 * console support.
670 */
671 if (co->index >= UART_NR)
672 co->index = 0;
673 uap = amba_ports[co->index];
674
675 uap->port.uartclk = clk_get_rate(uap->clk);
676
677 if (options)
678 uart_parse_options(options, &baud, &parity, &bits, &flow);
679 else
680 pl011_console_get_options(uap, &baud, &parity, &bits);
681
682 return uart_set_options(&uap->port, co, baud, parity, bits, flow);
683}
684
Vincent Sanders2d934862005-09-14 22:36:03 +0100685static struct uart_driver amba_reg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686static struct console amba_console = {
687 .name = "ttyAMA",
688 .write = pl011_console_write,
689 .device = uart_console_device,
690 .setup = pl011_console_setup,
691 .flags = CON_PRINTBUFFER,
692 .index = -1,
693 .data = &amba_reg,
694};
695
696#define AMBA_CONSOLE (&amba_console)
697#else
698#define AMBA_CONSOLE NULL
699#endif
700
701static struct uart_driver amba_reg = {
702 .owner = THIS_MODULE,
703 .driver_name = "ttyAMA",
704 .dev_name = "ttyAMA",
705 .major = SERIAL_AMBA_MAJOR,
706 .minor = SERIAL_AMBA_MINOR,
707 .nr = UART_NR,
708 .cons = AMBA_CONSOLE,
709};
710
711static int pl011_probe(struct amba_device *dev, void *id)
712{
713 struct uart_amba_port *uap;
714 void __iomem *base;
715 int i, ret;
716
717 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
718 if (amba_ports[i] == NULL)
719 break;
720
721 if (i == ARRAY_SIZE(amba_ports)) {
722 ret = -EBUSY;
723 goto out;
724 }
725
726 uap = kmalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
727 if (uap == NULL) {
728 ret = -ENOMEM;
729 goto out;
730 }
731
732 base = ioremap(dev->res.start, PAGE_SIZE);
733 if (!base) {
734 ret = -ENOMEM;
735 goto free;
736 }
737
738 memset(uap, 0, sizeof(struct uart_amba_port));
739 uap->clk = clk_get(&dev->dev, "UARTCLK");
740 if (IS_ERR(uap->clk)) {
741 ret = PTR_ERR(uap->clk);
742 goto unmap;
743 }
744
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 uap->port.dev = &dev->dev;
746 uap->port.mapbase = dev->res.start;
747 uap->port.membase = base;
748 uap->port.iotype = UPIO_MEM;
749 uap->port.irq = dev->irq[0];
750 uap->port.fifosize = 16;
751 uap->port.ops = &amba_pl011_pops;
752 uap->port.flags = UPF_BOOT_AUTOCONF;
753 uap->port.line = i;
754
755 amba_ports[i] = uap;
756
757 amba_set_drvdata(dev, uap);
758 ret = uart_add_one_port(&amba_reg, &uap->port);
759 if (ret) {
760 amba_set_drvdata(dev, NULL);
761 amba_ports[i] = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 clk_put(uap->clk);
763 unmap:
764 iounmap(base);
765 free:
766 kfree(uap);
767 }
768 out:
769 return ret;
770}
771
772static int pl011_remove(struct amba_device *dev)
773{
774 struct uart_amba_port *uap = amba_get_drvdata(dev);
775 int i;
776
777 amba_set_drvdata(dev, NULL);
778
779 uart_remove_one_port(&amba_reg, &uap->port);
780
781 for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
782 if (amba_ports[i] == uap)
783 amba_ports[i] = NULL;
784
785 iounmap(uap->port.membase);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786 clk_put(uap->clk);
787 kfree(uap);
788 return 0;
789}
790
791static struct amba_id pl011_ids[] __initdata = {
792 {
793 .id = 0x00041011,
794 .mask = 0x000fffff,
795 },
796 { 0, 0 },
797};
798
799static struct amba_driver pl011_driver = {
800 .drv = {
801 .name = "uart-pl011",
802 },
803 .id_table = pl011_ids,
804 .probe = pl011_probe,
805 .remove = pl011_remove,
806};
807
808static int __init pl011_init(void)
809{
810 int ret;
811 printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
812
813 ret = uart_register_driver(&amba_reg);
814 if (ret == 0) {
815 ret = amba_driver_register(&pl011_driver);
816 if (ret)
817 uart_unregister_driver(&amba_reg);
818 }
819 return ret;
820}
821
822static void __exit pl011_exit(void)
823{
824 amba_driver_unregister(&pl011_driver);
825 uart_unregister_driver(&amba_reg);
826}
827
828module_init(pl011_init);
829module_exit(pl011_exit);
830
831MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
832MODULE_DESCRIPTION("ARM AMBA serial port driver");
833MODULE_LICENSE("GPL");