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v3.1
  1/*
  2 *  Driver for AMBA serial ports
  3 *
  4 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
  5 *
  6 *  Copyright 1999 ARM Limited
  7 *  Copyright (C) 2000 Deep Blue Solutions Ltd.
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; either version 2 of the License, or
 12 * (at your option) any later version.
 13 *
 14 * This program is distributed in the hope that it will be useful,
 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 * GNU General Public License for more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program; if not, write to the Free Software
 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 22 *
 23 * This is a generic driver for ARM AMBA-type serial ports.  They
 24 * have a lot of 16550-like features, but are not register compatible.
 25 * Note that although they do have CTS, DCD and DSR inputs, they do
 26 * not have an RI input, nor do they have DTR or RTS outputs.  If
 27 * required, these have to be supplied via some other means (eg, GPIO)
 28 * and hooked into this driver.
 29 */
 30
 31#if defined(CONFIG_SERIAL_AMBA_PL010_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 32#define SUPPORT_SYSRQ
 33#endif
 34
 35#include <linux/module.h>
 36#include <linux/ioport.h>
 37#include <linux/init.h>
 38#include <linux/console.h>
 39#include <linux/sysrq.h>
 40#include <linux/device.h>
 41#include <linux/tty.h>
 42#include <linux/tty_flip.h>
 43#include <linux/serial_core.h>
 44#include <linux/serial.h>
 45#include <linux/amba/bus.h>
 46#include <linux/amba/serial.h>
 47#include <linux/clk.h>
 48#include <linux/slab.h>
 49
 50#include <asm/io.h>
 51
 52#define UART_NR		8
 53
 54#define SERIAL_AMBA_MAJOR	204
 55#define SERIAL_AMBA_MINOR	16
 56#define SERIAL_AMBA_NR		UART_NR
 57
 58#define AMBA_ISR_PASS_LIMIT	256
 59
 60#define UART_RX_DATA(s)		(((s) & UART01x_FR_RXFE) == 0)
 61#define UART_TX_READY(s)	(((s) & UART01x_FR_TXFF) == 0)
 62
 63#define UART_DUMMY_RSR_RX	256
 64#define UART_PORT_SIZE		64
 65
 66/*
 67 * We wrap our port structure around the generic uart_port.
 68 */
 69struct uart_amba_port {
 70	struct uart_port	port;
 71	struct clk		*clk;
 72	struct amba_device	*dev;
 73	struct amba_pl010_data	*data;
 74	unsigned int		old_status;
 75};
 76
 77static void pl010_stop_tx(struct uart_port *port)
 78{
 79	struct uart_amba_port *uap = (struct uart_amba_port *)port;
 80	unsigned int cr;
 81
 82	cr = readb(uap->port.membase + UART010_CR);
 83	cr &= ~UART010_CR_TIE;
 84	writel(cr, uap->port.membase + UART010_CR);
 85}
 86
 87static void pl010_start_tx(struct uart_port *port)
 88{
 89	struct uart_amba_port *uap = (struct uart_amba_port *)port;
 90	unsigned int cr;
 91
 92	cr = readb(uap->port.membase + UART010_CR);
 93	cr |= UART010_CR_TIE;
 94	writel(cr, uap->port.membase + UART010_CR);
 95}
 96
 97static void pl010_stop_rx(struct uart_port *port)
 98{
 99	struct uart_amba_port *uap = (struct uart_amba_port *)port;
100	unsigned int cr;
101
102	cr = readb(uap->port.membase + UART010_CR);
103	cr &= ~(UART010_CR_RIE | UART010_CR_RTIE);
104	writel(cr, uap->port.membase + UART010_CR);
105}
106
107static void pl010_enable_ms(struct uart_port *port)
108{
109	struct uart_amba_port *uap = (struct uart_amba_port *)port;
110	unsigned int cr;
111
112	cr = readb(uap->port.membase + UART010_CR);
113	cr |= UART010_CR_MSIE;
114	writel(cr, uap->port.membase + UART010_CR);
115}
116
117static void pl010_rx_chars(struct uart_amba_port *uap)
118{
119	struct tty_struct *tty = uap->port.state->port.tty;
120	unsigned int status, ch, flag, rsr, max_count = 256;
121
122	status = readb(uap->port.membase + UART01x_FR);
123	while (UART_RX_DATA(status) && max_count--) {
124		ch = readb(uap->port.membase + UART01x_DR);
125		flag = TTY_NORMAL;
126
127		uap->port.icount.rx++;
128
129		/*
130		 * Note that the error handling code is
131		 * out of the main execution path
132		 */
133		rsr = readb(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
134		if (unlikely(rsr & UART01x_RSR_ANY)) {
135			writel(0, uap->port.membase + UART01x_ECR);
136
137			if (rsr & UART01x_RSR_BE) {
138				rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
139				uap->port.icount.brk++;
140				if (uart_handle_break(&uap->port))
141					goto ignore_char;
142			} else if (rsr & UART01x_RSR_PE)
143				uap->port.icount.parity++;
144			else if (rsr & UART01x_RSR_FE)
145				uap->port.icount.frame++;
146			if (rsr & UART01x_RSR_OE)
147				uap->port.icount.overrun++;
148
149			rsr &= uap->port.read_status_mask;
150
151			if (rsr & UART01x_RSR_BE)
152				flag = TTY_BREAK;
153			else if (rsr & UART01x_RSR_PE)
154				flag = TTY_PARITY;
155			else if (rsr & UART01x_RSR_FE)
156				flag = TTY_FRAME;
157		}
158
159		if (uart_handle_sysrq_char(&uap->port, ch))
160			goto ignore_char;
161
162		uart_insert_char(&uap->port, rsr, UART01x_RSR_OE, ch, flag);
163
164	ignore_char:
165		status = readb(uap->port.membase + UART01x_FR);
166	}
167	spin_unlock(&uap->port.lock);
168	tty_flip_buffer_push(tty);
169	spin_lock(&uap->port.lock);
170}
171
172static void pl010_tx_chars(struct uart_amba_port *uap)
173{
174	struct circ_buf *xmit = &uap->port.state->xmit;
175	int count;
176
177	if (uap->port.x_char) {
178		writel(uap->port.x_char, uap->port.membase + UART01x_DR);
179		uap->port.icount.tx++;
180		uap->port.x_char = 0;
181		return;
182	}
183	if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
184		pl010_stop_tx(&uap->port);
185		return;
186	}
187
188	count = uap->port.fifosize >> 1;
189	do {
190		writel(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
191		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
192		uap->port.icount.tx++;
193		if (uart_circ_empty(xmit))
194			break;
195	} while (--count > 0);
196
197	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
198		uart_write_wakeup(&uap->port);
199
200	if (uart_circ_empty(xmit))
201		pl010_stop_tx(&uap->port);
202}
203
204static void pl010_modem_status(struct uart_amba_port *uap)
205{
206	unsigned int status, delta;
207
208	writel(0, uap->port.membase + UART010_ICR);
209
210	status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
211
212	delta = status ^ uap->old_status;
213	uap->old_status = status;
214
215	if (!delta)
216		return;
217
218	if (delta & UART01x_FR_DCD)
219		uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
220
221	if (delta & UART01x_FR_DSR)
222		uap->port.icount.dsr++;
223
224	if (delta & UART01x_FR_CTS)
225		uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
226
227	wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
228}
229
230static irqreturn_t pl010_int(int irq, void *dev_id)
231{
232	struct uart_amba_port *uap = dev_id;
233	unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
234	int handled = 0;
235
236	spin_lock(&uap->port.lock);
237
238	status = readb(uap->port.membase + UART010_IIR);
239	if (status) {
240		do {
241			if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
242				pl010_rx_chars(uap);
243			if (status & UART010_IIR_MIS)
244				pl010_modem_status(uap);
245			if (status & UART010_IIR_TIS)
246				pl010_tx_chars(uap);
247
248			if (pass_counter-- == 0)
249				break;
250
251			status = readb(uap->port.membase + UART010_IIR);
252		} while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
253				   UART010_IIR_TIS));
254		handled = 1;
255	}
256
257	spin_unlock(&uap->port.lock);
258
259	return IRQ_RETVAL(handled);
260}
261
262static unsigned int pl010_tx_empty(struct uart_port *port)
263{
264	struct uart_amba_port *uap = (struct uart_amba_port *)port;
265	unsigned int status = readb(uap->port.membase + UART01x_FR);
266	return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
267}
268
269static unsigned int pl010_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;
274
275	status = readb(uap->port.membase + UART01x_FR);
276	if (status & UART01x_FR_DCD)
277		result |= TIOCM_CAR;
278	if (status & UART01x_FR_DSR)
279		result |= TIOCM_DSR;
280	if (status & UART01x_FR_CTS)
281		result |= TIOCM_CTS;
282
283	return result;
284}
285
286static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
287{
288	struct uart_amba_port *uap = (struct uart_amba_port *)port;
289
290	if (uap->data)
291		uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl);
292}
293
294static void pl010_break_ctl(struct uart_port *port, int break_state)
295{
296	struct uart_amba_port *uap = (struct uart_amba_port *)port;
297	unsigned long flags;
298	unsigned int lcr_h;
299
300	spin_lock_irqsave(&uap->port.lock, flags);
301	lcr_h = readb(uap->port.membase + UART010_LCRH);
302	if (break_state == -1)
303		lcr_h |= UART01x_LCRH_BRK;
304	else
305		lcr_h &= ~UART01x_LCRH_BRK;
306	writel(lcr_h, uap->port.membase + UART010_LCRH);
307	spin_unlock_irqrestore(&uap->port.lock, flags);
308}
309
310static int pl010_startup(struct uart_port *port)
311{
312	struct uart_amba_port *uap = (struct uart_amba_port *)port;
313	int retval;
314
315	/*
316	 * Try to enable the clock producer.
317	 */
318	retval = clk_enable(uap->clk);
319	if (retval)
320		goto out;
321
322	uap->port.uartclk = clk_get_rate(uap->clk);
323
324	/*
325	 * Allocate the IRQ
326	 */
327	retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap);
328	if (retval)
329		goto clk_dis;
330
331	/*
332	 * initialise the old status of the modem signals
333	 */
334	uap->old_status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
335
336	/*
337	 * Finally, enable interrupts
338	 */
339	writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
340	       uap->port.membase + UART010_CR);
341
342	return 0;
343
344 clk_dis:
345	clk_disable(uap->clk);
346 out:
347	return retval;
348}
349
350static void pl010_shutdown(struct uart_port *port)
351{
352	struct uart_amba_port *uap = (struct uart_amba_port *)port;
353
354	/*
355	 * Free the interrupt
356	 */
357	free_irq(uap->port.irq, uap);
358
359	/*
360	 * disable all interrupts, disable the port
361	 */
362	writel(0, uap->port.membase + UART010_CR);
363
364	/* disable break condition and fifos */
365	writel(readb(uap->port.membase + UART010_LCRH) &
366		~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
367	       uap->port.membase + UART010_LCRH);
368
369	/*
370	 * Shut down the clock producer
371	 */
372	clk_disable(uap->clk);
373}
374
375static void
376pl010_set_termios(struct uart_port *port, struct ktermios *termios,
377		     struct ktermios *old)
378{
379	struct uart_amba_port *uap = (struct uart_amba_port *)port;
380	unsigned int lcr_h, old_cr;
381	unsigned long flags;
382	unsigned int baud, quot;
383
384	/*
385	 * Ask the core to calculate the divisor for us.
386	 */
387	baud = uart_get_baud_rate(port, termios, old, 0, uap->port.uartclk/16); 
388	quot = uart_get_divisor(port, baud);
389
390	switch (termios->c_cflag & CSIZE) {
391	case CS5:
392		lcr_h = UART01x_LCRH_WLEN_5;
393		break;
394	case CS6:
395		lcr_h = UART01x_LCRH_WLEN_6;
396		break;
397	case CS7:
398		lcr_h = UART01x_LCRH_WLEN_7;
399		break;
400	default: // CS8
401		lcr_h = UART01x_LCRH_WLEN_8;
402		break;
403	}
404	if (termios->c_cflag & CSTOPB)
405		lcr_h |= UART01x_LCRH_STP2;
406	if (termios->c_cflag & PARENB) {
407		lcr_h |= UART01x_LCRH_PEN;
408		if (!(termios->c_cflag & PARODD))
409			lcr_h |= UART01x_LCRH_EPS;
410	}
411	if (uap->port.fifosize > 1)
412		lcr_h |= UART01x_LCRH_FEN;
413
414	spin_lock_irqsave(&uap->port.lock, flags);
415
416	/*
417	 * Update the per-port timeout.
418	 */
419	uart_update_timeout(port, termios->c_cflag, baud);
420
421	uap->port.read_status_mask = UART01x_RSR_OE;
422	if (termios->c_iflag & INPCK)
423		uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
424	if (termios->c_iflag & (BRKINT | PARMRK))
425		uap->port.read_status_mask |= UART01x_RSR_BE;
426
427	/*
428	 * Characters to ignore
429	 */
430	uap->port.ignore_status_mask = 0;
431	if (termios->c_iflag & IGNPAR)
432		uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
433	if (termios->c_iflag & IGNBRK) {
434		uap->port.ignore_status_mask |= UART01x_RSR_BE;
435		/*
436		 * If we're ignoring parity and break indicators,
437		 * ignore overruns too (for real raw support).
438		 */
439		if (termios->c_iflag & IGNPAR)
440			uap->port.ignore_status_mask |= UART01x_RSR_OE;
441	}
442
443	/*
444	 * Ignore all characters if CREAD is not set.
445	 */
446	if ((termios->c_cflag & CREAD) == 0)
447		uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
448
449	/* first, disable everything */
450	old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
451
452	if (UART_ENABLE_MS(port, termios->c_cflag))
453		old_cr |= UART010_CR_MSIE;
454
455	writel(0, uap->port.membase + UART010_CR);
456
457	/* Set baud rate */
458	quot -= 1;
459	writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
460	writel(quot & 0xff, uap->port.membase + UART010_LCRL);
461
462	/*
463	 * ----------v----------v----------v----------v-----
464	 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
465	 * ----------^----------^----------^----------^-----
466	 */
467	writel(lcr_h, uap->port.membase + UART010_LCRH);
468	writel(old_cr, uap->port.membase + UART010_CR);
469
470	spin_unlock_irqrestore(&uap->port.lock, flags);
471}
472
473static void pl010_set_ldisc(struct uart_port *port, int new)
474{
475	if (new == N_PPS) {
476		port->flags |= UPF_HARDPPS_CD;
477		pl010_enable_ms(port);
478	} else
479		port->flags &= ~UPF_HARDPPS_CD;
480}
481
482static const char *pl010_type(struct uart_port *port)
483{
484	return port->type == PORT_AMBA ? "AMBA" : NULL;
485}
486
487/*
488 * Release the memory region(s) being used by 'port'
489 */
490static void pl010_release_port(struct uart_port *port)
491{
492	release_mem_region(port->mapbase, UART_PORT_SIZE);
493}
494
495/*
496 * Request the memory region(s) being used by 'port'
497 */
498static int pl010_request_port(struct uart_port *port)
499{
500	return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
501			!= NULL ? 0 : -EBUSY;
502}
503
504/*
505 * Configure/autoconfigure the port.
506 */
507static void pl010_config_port(struct uart_port *port, int flags)
508{
509	if (flags & UART_CONFIG_TYPE) {
510		port->type = PORT_AMBA;
511		pl010_request_port(port);
512	}
513}
514
515/*
516 * verify the new serial_struct (for TIOCSSERIAL).
517 */
518static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
519{
520	int ret = 0;
521	if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
522		ret = -EINVAL;
523	if (ser->irq < 0 || ser->irq >= nr_irqs)
524		ret = -EINVAL;
525	if (ser->baud_base < 9600)
526		ret = -EINVAL;
527	return ret;
528}
529
530static struct uart_ops amba_pl010_pops = {
531	.tx_empty	= pl010_tx_empty,
532	.set_mctrl	= pl010_set_mctrl,
533	.get_mctrl	= pl010_get_mctrl,
534	.stop_tx	= pl010_stop_tx,
535	.start_tx	= pl010_start_tx,
536	.stop_rx	= pl010_stop_rx,
537	.enable_ms	= pl010_enable_ms,
538	.break_ctl	= pl010_break_ctl,
539	.startup	= pl010_startup,
540	.shutdown	= pl010_shutdown,
541	.set_termios	= pl010_set_termios,
542	.set_ldisc	= pl010_set_ldisc,
543	.type		= pl010_type,
544	.release_port	= pl010_release_port,
545	.request_port	= pl010_request_port,
546	.config_port	= pl010_config_port,
547	.verify_port	= pl010_verify_port,
548};
549
550static struct uart_amba_port *amba_ports[UART_NR];
551
552#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
553
554static void pl010_console_putchar(struct uart_port *port, int ch)
555{
556	struct uart_amba_port *uap = (struct uart_amba_port *)port;
557	unsigned int status;
558
559	do {
560		status = readb(uap->port.membase + UART01x_FR);
561		barrier();
562	} while (!UART_TX_READY(status));
563	writel(ch, uap->port.membase + UART01x_DR);
564}
565
566static void
567pl010_console_write(struct console *co, const char *s, unsigned int count)
568{
569	struct uart_amba_port *uap = amba_ports[co->index];
570	unsigned int status, old_cr;
571
572	clk_enable(uap->clk);
573
574	/*
575	 *	First save the CR then disable the interrupts
576	 */
577	old_cr = readb(uap->port.membase + UART010_CR);
578	writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR);
579
580	uart_console_write(&uap->port, s, count, pl010_console_putchar);
581
582	/*
583	 *	Finally, wait for transmitter to become empty
584	 *	and restore the TCR
585	 */
586	do {
587		status = readb(uap->port.membase + UART01x_FR);
588		barrier();
589	} while (status & UART01x_FR_BUSY);
590	writel(old_cr, uap->port.membase + UART010_CR);
591
592	clk_disable(uap->clk);
593}
594
595static void __init
596pl010_console_get_options(struct uart_amba_port *uap, int *baud,
597			     int *parity, int *bits)
598{
599	if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
600		unsigned int lcr_h, quot;
601		lcr_h = readb(uap->port.membase + UART010_LCRH);
602
603		*parity = 'n';
604		if (lcr_h & UART01x_LCRH_PEN) {
605			if (lcr_h & UART01x_LCRH_EPS)
606				*parity = 'e';
607			else
608				*parity = 'o';
609		}
610
611		if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
612			*bits = 7;
613		else
614			*bits = 8;
615
616		quot = readb(uap->port.membase + UART010_LCRL) |
617		       readb(uap->port.membase + UART010_LCRM) << 8;
618		*baud = uap->port.uartclk / (16 * (quot + 1));
619	}
620}
621
622static int __init pl010_console_setup(struct console *co, char *options)
623{
624	struct uart_amba_port *uap;
625	int baud = 38400;
626	int bits = 8;
627	int parity = 'n';
628	int flow = 'n';
 
629
630	/*
631	 * Check whether an invalid uart number has been specified, and
632	 * if so, search for the first available port that does have
633	 * console support.
634	 */
635	if (co->index >= UART_NR)
636		co->index = 0;
637	uap = amba_ports[co->index];
638	if (!uap)
639		return -ENODEV;
640
 
 
 
 
641	uap->port.uartclk = clk_get_rate(uap->clk);
642
643	if (options)
644		uart_parse_options(options, &baud, &parity, &bits, &flow);
645	else
646		pl010_console_get_options(uap, &baud, &parity, &bits);
647
648	return uart_set_options(&uap->port, co, baud, parity, bits, flow);
649}
650
651static struct uart_driver amba_reg;
652static struct console amba_console = {
653	.name		= "ttyAM",
654	.write		= pl010_console_write,
655	.device		= uart_console_device,
656	.setup		= pl010_console_setup,
657	.flags		= CON_PRINTBUFFER,
658	.index		= -1,
659	.data		= &amba_reg,
660};
661
662#define AMBA_CONSOLE	&amba_console
663#else
664#define AMBA_CONSOLE	NULL
665#endif
666
667static struct uart_driver amba_reg = {
668	.owner			= THIS_MODULE,
669	.driver_name		= "ttyAM",
670	.dev_name		= "ttyAM",
671	.major			= SERIAL_AMBA_MAJOR,
672	.minor			= SERIAL_AMBA_MINOR,
673	.nr			= UART_NR,
674	.cons			= AMBA_CONSOLE,
675};
676
677static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
678{
679	struct uart_amba_port *uap;
680	void __iomem *base;
681	int i, ret;
682
683	for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
684		if (amba_ports[i] == NULL)
685			break;
686
687	if (i == ARRAY_SIZE(amba_ports)) {
688		ret = -EBUSY;
689		goto out;
690	}
691
692	uap = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
693	if (!uap) {
694		ret = -ENOMEM;
695		goto out;
696	}
697
698	base = ioremap(dev->res.start, resource_size(&dev->res));
699	if (!base) {
700		ret = -ENOMEM;
701		goto free;
702	}
703
704	uap->clk = clk_get(&dev->dev, NULL);
705	if (IS_ERR(uap->clk)) {
706		ret = PTR_ERR(uap->clk);
707		goto unmap;
708	}
709
710	uap->port.dev = &dev->dev;
711	uap->port.mapbase = dev->res.start;
712	uap->port.membase = base;
713	uap->port.iotype = UPIO_MEM;
714	uap->port.irq = dev->irq[0];
715	uap->port.fifosize = 16;
716	uap->port.ops = &amba_pl010_pops;
717	uap->port.flags = UPF_BOOT_AUTOCONF;
718	uap->port.line = i;
719	uap->dev = dev;
720	uap->data = dev->dev.platform_data;
721
722	amba_ports[i] = uap;
723
724	amba_set_drvdata(dev, uap);
725	ret = uart_add_one_port(&amba_reg, &uap->port);
726	if (ret) {
727		amba_set_drvdata(dev, NULL);
728		amba_ports[i] = NULL;
729		clk_put(uap->clk);
730 unmap:
731		iounmap(base);
732 free:
733		kfree(uap);
734	}
735 out:
736	return ret;
737}
738
739static int pl010_remove(struct amba_device *dev)
740{
741	struct uart_amba_port *uap = amba_get_drvdata(dev);
742	int i;
743
744	amba_set_drvdata(dev, NULL);
745
746	uart_remove_one_port(&amba_reg, &uap->port);
747
748	for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
749		if (amba_ports[i] == uap)
750			amba_ports[i] = NULL;
751
752	iounmap(uap->port.membase);
753	clk_put(uap->clk);
754	kfree(uap);
755	return 0;
756}
757
758static int pl010_suspend(struct amba_device *dev, pm_message_t state)
 
759{
760	struct uart_amba_port *uap = amba_get_drvdata(dev);
761
762	if (uap)
763		uart_suspend_port(&amba_reg, &uap->port);
764
765	return 0;
766}
767
768static int pl010_resume(struct amba_device *dev)
769{
770	struct uart_amba_port *uap = amba_get_drvdata(dev);
771
772	if (uap)
773		uart_resume_port(&amba_reg, &uap->port);
774
775	return 0;
776}
 
 
 
777
778static struct amba_id pl010_ids[] = {
779	{
780		.id	= 0x00041010,
781		.mask	= 0x000fffff,
782	},
783	{ 0, 0 },
784};
785
 
 
786static struct amba_driver pl010_driver = {
787	.drv = {
788		.name	= "uart-pl010",
 
789	},
790	.id_table	= pl010_ids,
791	.probe		= pl010_probe,
792	.remove		= pl010_remove,
793	.suspend	= pl010_suspend,
794	.resume		= pl010_resume,
795};
796
797static int __init pl010_init(void)
798{
799	int ret;
800
801	printk(KERN_INFO "Serial: AMBA driver\n");
802
803	ret = uart_register_driver(&amba_reg);
804	if (ret == 0) {
805		ret = amba_driver_register(&pl010_driver);
806		if (ret)
807			uart_unregister_driver(&amba_reg);
808	}
809	return ret;
810}
811
812static void __exit pl010_exit(void)
813{
814	amba_driver_unregister(&pl010_driver);
815	uart_unregister_driver(&amba_reg);
816}
817
818module_init(pl010_init);
819module_exit(pl010_exit);
820
821MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
822MODULE_DESCRIPTION("ARM AMBA serial port driver");
823MODULE_LICENSE("GPL");
v3.15
  1/*
  2 *  Driver for AMBA serial ports
  3 *
  4 *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
  5 *
  6 *  Copyright 1999 ARM Limited
  7 *  Copyright (C) 2000 Deep Blue Solutions Ltd.
  8 *
  9 * This program is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License as published by
 11 * the Free Software Foundation; either version 2 of the License, or
 12 * (at your option) any later version.
 13 *
 14 * This program is distributed in the hope that it will be useful,
 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 * GNU General Public License for more details.
 18 *
 19 * You should have received a copy of the GNU General Public License
 20 * along with this program; if not, write to the Free Software
 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 22 *
 23 * This is a generic driver for ARM AMBA-type serial ports.  They
 24 * have a lot of 16550-like features, but are not register compatible.
 25 * Note that although they do have CTS, DCD and DSR inputs, they do
 26 * not have an RI input, nor do they have DTR or RTS outputs.  If
 27 * required, these have to be supplied via some other means (eg, GPIO)
 28 * and hooked into this driver.
 29 */
 30
 31#if defined(CONFIG_SERIAL_AMBA_PL010_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 32#define SUPPORT_SYSRQ
 33#endif
 34
 35#include <linux/module.h>
 36#include <linux/ioport.h>
 37#include <linux/init.h>
 38#include <linux/console.h>
 39#include <linux/sysrq.h>
 40#include <linux/device.h>
 41#include <linux/tty.h>
 42#include <linux/tty_flip.h>
 43#include <linux/serial_core.h>
 44#include <linux/serial.h>
 45#include <linux/amba/bus.h>
 46#include <linux/amba/serial.h>
 47#include <linux/clk.h>
 48#include <linux/slab.h>
 49
 50#include <asm/io.h>
 51
 52#define UART_NR		8
 53
 54#define SERIAL_AMBA_MAJOR	204
 55#define SERIAL_AMBA_MINOR	16
 56#define SERIAL_AMBA_NR		UART_NR
 57
 58#define AMBA_ISR_PASS_LIMIT	256
 59
 60#define UART_RX_DATA(s)		(((s) & UART01x_FR_RXFE) == 0)
 61#define UART_TX_READY(s)	(((s) & UART01x_FR_TXFF) == 0)
 62
 63#define UART_DUMMY_RSR_RX	256
 64#define UART_PORT_SIZE		64
 65
 66/*
 67 * We wrap our port structure around the generic uart_port.
 68 */
 69struct uart_amba_port {
 70	struct uart_port	port;
 71	struct clk		*clk;
 72	struct amba_device	*dev;
 73	struct amba_pl010_data	*data;
 74	unsigned int		old_status;
 75};
 76
 77static void pl010_stop_tx(struct uart_port *port)
 78{
 79	struct uart_amba_port *uap = (struct uart_amba_port *)port;
 80	unsigned int cr;
 81
 82	cr = readb(uap->port.membase + UART010_CR);
 83	cr &= ~UART010_CR_TIE;
 84	writel(cr, uap->port.membase + UART010_CR);
 85}
 86
 87static void pl010_start_tx(struct uart_port *port)
 88{
 89	struct uart_amba_port *uap = (struct uart_amba_port *)port;
 90	unsigned int cr;
 91
 92	cr = readb(uap->port.membase + UART010_CR);
 93	cr |= UART010_CR_TIE;
 94	writel(cr, uap->port.membase + UART010_CR);
 95}
 96
 97static void pl010_stop_rx(struct uart_port *port)
 98{
 99	struct uart_amba_port *uap = (struct uart_amba_port *)port;
100	unsigned int cr;
101
102	cr = readb(uap->port.membase + UART010_CR);
103	cr &= ~(UART010_CR_RIE | UART010_CR_RTIE);
104	writel(cr, uap->port.membase + UART010_CR);
105}
106
107static void pl010_enable_ms(struct uart_port *port)
108{
109	struct uart_amba_port *uap = (struct uart_amba_port *)port;
110	unsigned int cr;
111
112	cr = readb(uap->port.membase + UART010_CR);
113	cr |= UART010_CR_MSIE;
114	writel(cr, uap->port.membase + UART010_CR);
115}
116
117static void pl010_rx_chars(struct uart_amba_port *uap)
118{
 
119	unsigned int status, ch, flag, rsr, max_count = 256;
120
121	status = readb(uap->port.membase + UART01x_FR);
122	while (UART_RX_DATA(status) && max_count--) {
123		ch = readb(uap->port.membase + UART01x_DR);
124		flag = TTY_NORMAL;
125
126		uap->port.icount.rx++;
127
128		/*
129		 * Note that the error handling code is
130		 * out of the main execution path
131		 */
132		rsr = readb(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
133		if (unlikely(rsr & UART01x_RSR_ANY)) {
134			writel(0, uap->port.membase + UART01x_ECR);
135
136			if (rsr & UART01x_RSR_BE) {
137				rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
138				uap->port.icount.brk++;
139				if (uart_handle_break(&uap->port))
140					goto ignore_char;
141			} else if (rsr & UART01x_RSR_PE)
142				uap->port.icount.parity++;
143			else if (rsr & UART01x_RSR_FE)
144				uap->port.icount.frame++;
145			if (rsr & UART01x_RSR_OE)
146				uap->port.icount.overrun++;
147
148			rsr &= uap->port.read_status_mask;
149
150			if (rsr & UART01x_RSR_BE)
151				flag = TTY_BREAK;
152			else if (rsr & UART01x_RSR_PE)
153				flag = TTY_PARITY;
154			else if (rsr & UART01x_RSR_FE)
155				flag = TTY_FRAME;
156		}
157
158		if (uart_handle_sysrq_char(&uap->port, ch))
159			goto ignore_char;
160
161		uart_insert_char(&uap->port, rsr, UART01x_RSR_OE, ch, flag);
162
163	ignore_char:
164		status = readb(uap->port.membase + UART01x_FR);
165	}
166	spin_unlock(&uap->port.lock);
167	tty_flip_buffer_push(&uap->port.state->port);
168	spin_lock(&uap->port.lock);
169}
170
171static void pl010_tx_chars(struct uart_amba_port *uap)
172{
173	struct circ_buf *xmit = &uap->port.state->xmit;
174	int count;
175
176	if (uap->port.x_char) {
177		writel(uap->port.x_char, uap->port.membase + UART01x_DR);
178		uap->port.icount.tx++;
179		uap->port.x_char = 0;
180		return;
181	}
182	if (uart_circ_empty(xmit) || uart_tx_stopped(&uap->port)) {
183		pl010_stop_tx(&uap->port);
184		return;
185	}
186
187	count = uap->port.fifosize >> 1;
188	do {
189		writel(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
190		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
191		uap->port.icount.tx++;
192		if (uart_circ_empty(xmit))
193			break;
194	} while (--count > 0);
195
196	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
197		uart_write_wakeup(&uap->port);
198
199	if (uart_circ_empty(xmit))
200		pl010_stop_tx(&uap->port);
201}
202
203static void pl010_modem_status(struct uart_amba_port *uap)
204{
205	unsigned int status, delta;
206
207	writel(0, uap->port.membase + UART010_ICR);
208
209	status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
210
211	delta = status ^ uap->old_status;
212	uap->old_status = status;
213
214	if (!delta)
215		return;
216
217	if (delta & UART01x_FR_DCD)
218		uart_handle_dcd_change(&uap->port, status & UART01x_FR_DCD);
219
220	if (delta & UART01x_FR_DSR)
221		uap->port.icount.dsr++;
222
223	if (delta & UART01x_FR_CTS)
224		uart_handle_cts_change(&uap->port, status & UART01x_FR_CTS);
225
226	wake_up_interruptible(&uap->port.state->port.delta_msr_wait);
227}
228
229static irqreturn_t pl010_int(int irq, void *dev_id)
230{
231	struct uart_amba_port *uap = dev_id;
232	unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
233	int handled = 0;
234
235	spin_lock(&uap->port.lock);
236
237	status = readb(uap->port.membase + UART010_IIR);
238	if (status) {
239		do {
240			if (status & (UART010_IIR_RTIS | UART010_IIR_RIS))
241				pl010_rx_chars(uap);
242			if (status & UART010_IIR_MIS)
243				pl010_modem_status(uap);
244			if (status & UART010_IIR_TIS)
245				pl010_tx_chars(uap);
246
247			if (pass_counter-- == 0)
248				break;
249
250			status = readb(uap->port.membase + UART010_IIR);
251		} while (status & (UART010_IIR_RTIS | UART010_IIR_RIS |
252				   UART010_IIR_TIS));
253		handled = 1;
254	}
255
256	spin_unlock(&uap->port.lock);
257
258	return IRQ_RETVAL(handled);
259}
260
261static unsigned int pl010_tx_empty(struct uart_port *port)
262{
263	struct uart_amba_port *uap = (struct uart_amba_port *)port;
264	unsigned int status = readb(uap->port.membase + UART01x_FR);
265	return status & UART01x_FR_BUSY ? 0 : TIOCSER_TEMT;
266}
267
268static unsigned int pl010_get_mctrl(struct uart_port *port)
269{
270	struct uart_amba_port *uap = (struct uart_amba_port *)port;
271	unsigned int result = 0;
272	unsigned int status;
273
274	status = readb(uap->port.membase + UART01x_FR);
275	if (status & UART01x_FR_DCD)
276		result |= TIOCM_CAR;
277	if (status & UART01x_FR_DSR)
278		result |= TIOCM_DSR;
279	if (status & UART01x_FR_CTS)
280		result |= TIOCM_CTS;
281
282	return result;
283}
284
285static void pl010_set_mctrl(struct uart_port *port, unsigned int mctrl)
286{
287	struct uart_amba_port *uap = (struct uart_amba_port *)port;
288
289	if (uap->data)
290		uap->data->set_mctrl(uap->dev, uap->port.membase, mctrl);
291}
292
293static void pl010_break_ctl(struct uart_port *port, int break_state)
294{
295	struct uart_amba_port *uap = (struct uart_amba_port *)port;
296	unsigned long flags;
297	unsigned int lcr_h;
298
299	spin_lock_irqsave(&uap->port.lock, flags);
300	lcr_h = readb(uap->port.membase + UART010_LCRH);
301	if (break_state == -1)
302		lcr_h |= UART01x_LCRH_BRK;
303	else
304		lcr_h &= ~UART01x_LCRH_BRK;
305	writel(lcr_h, uap->port.membase + UART010_LCRH);
306	spin_unlock_irqrestore(&uap->port.lock, flags);
307}
308
309static int pl010_startup(struct uart_port *port)
310{
311	struct uart_amba_port *uap = (struct uart_amba_port *)port;
312	int retval;
313
314	/*
315	 * Try to enable the clock producer.
316	 */
317	retval = clk_prepare_enable(uap->clk);
318	if (retval)
319		goto out;
320
321	uap->port.uartclk = clk_get_rate(uap->clk);
322
323	/*
324	 * Allocate the IRQ
325	 */
326	retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap);
327	if (retval)
328		goto clk_dis;
329
330	/*
331	 * initialise the old status of the modem signals
332	 */
333	uap->old_status = readb(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
334
335	/*
336	 * Finally, enable interrupts
337	 */
338	writel(UART01x_CR_UARTEN | UART010_CR_RIE | UART010_CR_RTIE,
339	       uap->port.membase + UART010_CR);
340
341	return 0;
342
343 clk_dis:
344	clk_disable_unprepare(uap->clk);
345 out:
346	return retval;
347}
348
349static void pl010_shutdown(struct uart_port *port)
350{
351	struct uart_amba_port *uap = (struct uart_amba_port *)port;
352
353	/*
354	 * Free the interrupt
355	 */
356	free_irq(uap->port.irq, uap);
357
358	/*
359	 * disable all interrupts, disable the port
360	 */
361	writel(0, uap->port.membase + UART010_CR);
362
363	/* disable break condition and fifos */
364	writel(readb(uap->port.membase + UART010_LCRH) &
365		~(UART01x_LCRH_BRK | UART01x_LCRH_FEN),
366	       uap->port.membase + UART010_LCRH);
367
368	/*
369	 * Shut down the clock producer
370	 */
371	clk_disable_unprepare(uap->clk);
372}
373
374static void
375pl010_set_termios(struct uart_port *port, struct ktermios *termios,
376		     struct ktermios *old)
377{
378	struct uart_amba_port *uap = (struct uart_amba_port *)port;
379	unsigned int lcr_h, old_cr;
380	unsigned long flags;
381	unsigned int baud, quot;
382
383	/*
384	 * Ask the core to calculate the divisor for us.
385	 */
386	baud = uart_get_baud_rate(port, termios, old, 0, uap->port.uartclk/16); 
387	quot = uart_get_divisor(port, baud);
388
389	switch (termios->c_cflag & CSIZE) {
390	case CS5:
391		lcr_h = UART01x_LCRH_WLEN_5;
392		break;
393	case CS6:
394		lcr_h = UART01x_LCRH_WLEN_6;
395		break;
396	case CS7:
397		lcr_h = UART01x_LCRH_WLEN_7;
398		break;
399	default: // CS8
400		lcr_h = UART01x_LCRH_WLEN_8;
401		break;
402	}
403	if (termios->c_cflag & CSTOPB)
404		lcr_h |= UART01x_LCRH_STP2;
405	if (termios->c_cflag & PARENB) {
406		lcr_h |= UART01x_LCRH_PEN;
407		if (!(termios->c_cflag & PARODD))
408			lcr_h |= UART01x_LCRH_EPS;
409	}
410	if (uap->port.fifosize > 1)
411		lcr_h |= UART01x_LCRH_FEN;
412
413	spin_lock_irqsave(&uap->port.lock, flags);
414
415	/*
416	 * Update the per-port timeout.
417	 */
418	uart_update_timeout(port, termios->c_cflag, baud);
419
420	uap->port.read_status_mask = UART01x_RSR_OE;
421	if (termios->c_iflag & INPCK)
422		uap->port.read_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
423	if (termios->c_iflag & (BRKINT | PARMRK))
424		uap->port.read_status_mask |= UART01x_RSR_BE;
425
426	/*
427	 * Characters to ignore
428	 */
429	uap->port.ignore_status_mask = 0;
430	if (termios->c_iflag & IGNPAR)
431		uap->port.ignore_status_mask |= UART01x_RSR_FE | UART01x_RSR_PE;
432	if (termios->c_iflag & IGNBRK) {
433		uap->port.ignore_status_mask |= UART01x_RSR_BE;
434		/*
435		 * If we're ignoring parity and break indicators,
436		 * ignore overruns too (for real raw support).
437		 */
438		if (termios->c_iflag & IGNPAR)
439			uap->port.ignore_status_mask |= UART01x_RSR_OE;
440	}
441
442	/*
443	 * Ignore all characters if CREAD is not set.
444	 */
445	if ((termios->c_cflag & CREAD) == 0)
446		uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
447
448	/* first, disable everything */
449	old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
450
451	if (UART_ENABLE_MS(port, termios->c_cflag))
452		old_cr |= UART010_CR_MSIE;
453
454	writel(0, uap->port.membase + UART010_CR);
455
456	/* Set baud rate */
457	quot -= 1;
458	writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
459	writel(quot & 0xff, uap->port.membase + UART010_LCRL);
460
461	/*
462	 * ----------v----------v----------v----------v-----
463	 * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L
464	 * ----------^----------^----------^----------^-----
465	 */
466	writel(lcr_h, uap->port.membase + UART010_LCRH);
467	writel(old_cr, uap->port.membase + UART010_CR);
468
469	spin_unlock_irqrestore(&uap->port.lock, flags);
470}
471
472static void pl010_set_ldisc(struct uart_port *port, int new)
473{
474	if (new == N_PPS) {
475		port->flags |= UPF_HARDPPS_CD;
476		pl010_enable_ms(port);
477	} else
478		port->flags &= ~UPF_HARDPPS_CD;
479}
480
481static const char *pl010_type(struct uart_port *port)
482{
483	return port->type == PORT_AMBA ? "AMBA" : NULL;
484}
485
486/*
487 * Release the memory region(s) being used by 'port'
488 */
489static void pl010_release_port(struct uart_port *port)
490{
491	release_mem_region(port->mapbase, UART_PORT_SIZE);
492}
493
494/*
495 * Request the memory region(s) being used by 'port'
496 */
497static int pl010_request_port(struct uart_port *port)
498{
499	return request_mem_region(port->mapbase, UART_PORT_SIZE, "uart-pl010")
500			!= NULL ? 0 : -EBUSY;
501}
502
503/*
504 * Configure/autoconfigure the port.
505 */
506static void pl010_config_port(struct uart_port *port, int flags)
507{
508	if (flags & UART_CONFIG_TYPE) {
509		port->type = PORT_AMBA;
510		pl010_request_port(port);
511	}
512}
513
514/*
515 * verify the new serial_struct (for TIOCSSERIAL).
516 */
517static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
518{
519	int ret = 0;
520	if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
521		ret = -EINVAL;
522	if (ser->irq < 0 || ser->irq >= nr_irqs)
523		ret = -EINVAL;
524	if (ser->baud_base < 9600)
525		ret = -EINVAL;
526	return ret;
527}
528
529static struct uart_ops amba_pl010_pops = {
530	.tx_empty	= pl010_tx_empty,
531	.set_mctrl	= pl010_set_mctrl,
532	.get_mctrl	= pl010_get_mctrl,
533	.stop_tx	= pl010_stop_tx,
534	.start_tx	= pl010_start_tx,
535	.stop_rx	= pl010_stop_rx,
536	.enable_ms	= pl010_enable_ms,
537	.break_ctl	= pl010_break_ctl,
538	.startup	= pl010_startup,
539	.shutdown	= pl010_shutdown,
540	.set_termios	= pl010_set_termios,
541	.set_ldisc	= pl010_set_ldisc,
542	.type		= pl010_type,
543	.release_port	= pl010_release_port,
544	.request_port	= pl010_request_port,
545	.config_port	= pl010_config_port,
546	.verify_port	= pl010_verify_port,
547};
548
549static struct uart_amba_port *amba_ports[UART_NR];
550
551#ifdef CONFIG_SERIAL_AMBA_PL010_CONSOLE
552
553static void pl010_console_putchar(struct uart_port *port, int ch)
554{
555	struct uart_amba_port *uap = (struct uart_amba_port *)port;
556	unsigned int status;
557
558	do {
559		status = readb(uap->port.membase + UART01x_FR);
560		barrier();
561	} while (!UART_TX_READY(status));
562	writel(ch, uap->port.membase + UART01x_DR);
563}
564
565static void
566pl010_console_write(struct console *co, const char *s, unsigned int count)
567{
568	struct uart_amba_port *uap = amba_ports[co->index];
569	unsigned int status, old_cr;
570
571	clk_enable(uap->clk);
572
573	/*
574	 *	First save the CR then disable the interrupts
575	 */
576	old_cr = readb(uap->port.membase + UART010_CR);
577	writel(UART01x_CR_UARTEN, uap->port.membase + UART010_CR);
578
579	uart_console_write(&uap->port, s, count, pl010_console_putchar);
580
581	/*
582	 *	Finally, wait for transmitter to become empty
583	 *	and restore the TCR
584	 */
585	do {
586		status = readb(uap->port.membase + UART01x_FR);
587		barrier();
588	} while (status & UART01x_FR_BUSY);
589	writel(old_cr, uap->port.membase + UART010_CR);
590
591	clk_disable(uap->clk);
592}
593
594static void __init
595pl010_console_get_options(struct uart_amba_port *uap, int *baud,
596			     int *parity, int *bits)
597{
598	if (readb(uap->port.membase + UART010_CR) & UART01x_CR_UARTEN) {
599		unsigned int lcr_h, quot;
600		lcr_h = readb(uap->port.membase + UART010_LCRH);
601
602		*parity = 'n';
603		if (lcr_h & UART01x_LCRH_PEN) {
604			if (lcr_h & UART01x_LCRH_EPS)
605				*parity = 'e';
606			else
607				*parity = 'o';
608		}
609
610		if ((lcr_h & 0x60) == UART01x_LCRH_WLEN_7)
611			*bits = 7;
612		else
613			*bits = 8;
614
615		quot = readb(uap->port.membase + UART010_LCRL) |
616		       readb(uap->port.membase + UART010_LCRM) << 8;
617		*baud = uap->port.uartclk / (16 * (quot + 1));
618	}
619}
620
621static int __init pl010_console_setup(struct console *co, char *options)
622{
623	struct uart_amba_port *uap;
624	int baud = 38400;
625	int bits = 8;
626	int parity = 'n';
627	int flow = 'n';
628	int ret;
629
630	/*
631	 * Check whether an invalid uart number has been specified, and
632	 * if so, search for the first available port that does have
633	 * console support.
634	 */
635	if (co->index >= UART_NR)
636		co->index = 0;
637	uap = amba_ports[co->index];
638	if (!uap)
639		return -ENODEV;
640
641	ret = clk_prepare(uap->clk);
642	if (ret)
643		return ret;
644
645	uap->port.uartclk = clk_get_rate(uap->clk);
646
647	if (options)
648		uart_parse_options(options, &baud, &parity, &bits, &flow);
649	else
650		pl010_console_get_options(uap, &baud, &parity, &bits);
651
652	return uart_set_options(&uap->port, co, baud, parity, bits, flow);
653}
654
655static struct uart_driver amba_reg;
656static struct console amba_console = {
657	.name		= "ttyAM",
658	.write		= pl010_console_write,
659	.device		= uart_console_device,
660	.setup		= pl010_console_setup,
661	.flags		= CON_PRINTBUFFER,
662	.index		= -1,
663	.data		= &amba_reg,
664};
665
666#define AMBA_CONSOLE	&amba_console
667#else
668#define AMBA_CONSOLE	NULL
669#endif
670
671static struct uart_driver amba_reg = {
672	.owner			= THIS_MODULE,
673	.driver_name		= "ttyAM",
674	.dev_name		= "ttyAM",
675	.major			= SERIAL_AMBA_MAJOR,
676	.minor			= SERIAL_AMBA_MINOR,
677	.nr			= UART_NR,
678	.cons			= AMBA_CONSOLE,
679};
680
681static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
682{
683	struct uart_amba_port *uap;
684	void __iomem *base;
685	int i, ret;
686
687	for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
688		if (amba_ports[i] == NULL)
689			break;
690
691	if (i == ARRAY_SIZE(amba_ports)) {
692		ret = -EBUSY;
693		goto out;
694	}
695
696	uap = kzalloc(sizeof(struct uart_amba_port), GFP_KERNEL);
697	if (!uap) {
698		ret = -ENOMEM;
699		goto out;
700	}
701
702	base = ioremap(dev->res.start, resource_size(&dev->res));
703	if (!base) {
704		ret = -ENOMEM;
705		goto free;
706	}
707
708	uap->clk = clk_get(&dev->dev, NULL);
709	if (IS_ERR(uap->clk)) {
710		ret = PTR_ERR(uap->clk);
711		goto unmap;
712	}
713
714	uap->port.dev = &dev->dev;
715	uap->port.mapbase = dev->res.start;
716	uap->port.membase = base;
717	uap->port.iotype = UPIO_MEM;
718	uap->port.irq = dev->irq[0];
719	uap->port.fifosize = 16;
720	uap->port.ops = &amba_pl010_pops;
721	uap->port.flags = UPF_BOOT_AUTOCONF;
722	uap->port.line = i;
723	uap->dev = dev;
724	uap->data = dev_get_platdata(&dev->dev);
725
726	amba_ports[i] = uap;
727
728	amba_set_drvdata(dev, uap);
729	ret = uart_add_one_port(&amba_reg, &uap->port);
730	if (ret) {
 
731		amba_ports[i] = NULL;
732		clk_put(uap->clk);
733 unmap:
734		iounmap(base);
735 free:
736		kfree(uap);
737	}
738 out:
739	return ret;
740}
741
742static int pl010_remove(struct amba_device *dev)
743{
744	struct uart_amba_port *uap = amba_get_drvdata(dev);
745	int i;
746
 
 
747	uart_remove_one_port(&amba_reg, &uap->port);
748
749	for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
750		if (amba_ports[i] == uap)
751			amba_ports[i] = NULL;
752
753	iounmap(uap->port.membase);
754	clk_put(uap->clk);
755	kfree(uap);
756	return 0;
757}
758
759#ifdef CONFIG_PM_SLEEP
760static int pl010_suspend(struct device *dev)
761{
762	struct uart_amba_port *uap = dev_get_drvdata(dev);
763
764	if (uap)
765		uart_suspend_port(&amba_reg, &uap->port);
766
767	return 0;
768}
769
770static int pl010_resume(struct device *dev)
771{
772	struct uart_amba_port *uap = dev_get_drvdata(dev);
773
774	if (uap)
775		uart_resume_port(&amba_reg, &uap->port);
776
777	return 0;
778}
779#endif
780
781static SIMPLE_DEV_PM_OPS(pl010_dev_pm_ops, pl010_suspend, pl010_resume);
782
783static struct amba_id pl010_ids[] = {
784	{
785		.id	= 0x00041010,
786		.mask	= 0x000fffff,
787	},
788	{ 0, 0 },
789};
790
791MODULE_DEVICE_TABLE(amba, pl010_ids);
792
793static struct amba_driver pl010_driver = {
794	.drv = {
795		.name	= "uart-pl010",
796		.pm	= &pl010_dev_pm_ops,
797	},
798	.id_table	= pl010_ids,
799	.probe		= pl010_probe,
800	.remove		= pl010_remove,
 
 
801};
802
803static int __init pl010_init(void)
804{
805	int ret;
806
807	printk(KERN_INFO "Serial: AMBA driver\n");
808
809	ret = uart_register_driver(&amba_reg);
810	if (ret == 0) {
811		ret = amba_driver_register(&pl010_driver);
812		if (ret)
813			uart_unregister_driver(&amba_reg);
814	}
815	return ret;
816}
817
818static void __exit pl010_exit(void)
819{
820	amba_driver_unregister(&pl010_driver);
821	uart_unregister_driver(&amba_reg);
822}
823
824module_init(pl010_init);
825module_exit(pl010_exit);
826
827MODULE_AUTHOR("ARM Ltd/Deep Blue Solutions Ltd");
828MODULE_DESCRIPTION("ARM AMBA serial port driver");
829MODULE_LICENSE("GPL");