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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 UART_OSAMP		0x14
 75#define  OSAMP_DEFAULT_DIVISOR	16
 76#define  OSAMP_DIVISORS_MASK	0x3F3F3F3F
 77
 78#define MVEBU_NR_UARTS		2
 79
 80#define MVEBU_UART_TYPE		"mvebu-uart"
 81#define DRIVER_NAME		"mvebu_serial"
 82
 83enum {
 84	/* Either there is only one summed IRQ... */
 85	UART_IRQ_SUM = 0,
 86	/* ...or there are two separate IRQ for RX and TX */
 87	UART_RX_IRQ = 0,
 88	UART_TX_IRQ,
 89	UART_IRQ_COUNT
 90};
 91
 92/* Diverging register offsets */
 93struct uart_regs_layout {
 94	unsigned int rbr;
 95	unsigned int tsh;
 96	unsigned int ctrl;
 97	unsigned int intr;
 98};
 99
100/* Diverging flags */
101struct uart_flags {
102	unsigned int ctrl_tx_rdy_int;
103	unsigned int ctrl_rx_rdy_int;
104	unsigned int stat_tx_rdy;
105	unsigned int stat_rx_rdy;
106};
107
108/* Driver data, a structure for each UART port */
109struct mvebu_uart_driver_data {
110	bool is_ext;
111	struct uart_regs_layout regs;
112	struct uart_flags flags;
113};
114
115/* Saved registers during suspend */
116struct mvebu_uart_pm_regs {
117	unsigned int rbr;
118	unsigned int tsh;
119	unsigned int ctrl;
120	unsigned int intr;
121	unsigned int stat;
122	unsigned int brdv;
123	unsigned int osamp;
124};
125
126/* MVEBU UART driver structure */
127struct mvebu_uart {
128	struct uart_port *port;
129	struct clk *clk;
130	int irq[UART_IRQ_COUNT];
131	unsigned char __iomem *nb;
132	struct mvebu_uart_driver_data *data;
133#if defined(CONFIG_PM)
134	struct mvebu_uart_pm_regs pm_regs;
135#endif /* CONFIG_PM */
136};
137
138static struct mvebu_uart *to_mvuart(struct uart_port *port)
139{
140	return (struct mvebu_uart *)port->private_data;
141}
142
143#define IS_EXTENDED(port) (to_mvuart(port)->data->is_ext)
144
145#define UART_RBR(port) (to_mvuart(port)->data->regs.rbr)
146#define UART_TSH(port) (to_mvuart(port)->data->regs.tsh)
147#define UART_CTRL(port) (to_mvuart(port)->data->regs.ctrl)
148#define UART_INTR(port) (to_mvuart(port)->data->regs.intr)
149
150#define CTRL_TX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_tx_rdy_int)
151#define CTRL_RX_RDY_INT(port) (to_mvuart(port)->data->flags.ctrl_rx_rdy_int)
152#define STAT_TX_RDY(port) (to_mvuart(port)->data->flags.stat_tx_rdy)
153#define STAT_RX_RDY(port) (to_mvuart(port)->data->flags.stat_rx_rdy)
154
155static struct uart_port mvebu_uart_ports[MVEBU_NR_UARTS];
156
157/* Core UART Driver Operations */
158static unsigned int mvebu_uart_tx_empty(struct uart_port *port)
159{
160	unsigned long flags;
161	unsigned int st;
162
163	spin_lock_irqsave(&port->lock, flags);
164	st = readl(port->membase + UART_STAT);
165	spin_unlock_irqrestore(&port->lock, flags);
166
167	return (st & STAT_TX_FIFO_EMP) ? TIOCSER_TEMT : 0;
168}
169
170static unsigned int mvebu_uart_get_mctrl(struct uart_port *port)
171{
172	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
173}
174
175static void mvebu_uart_set_mctrl(struct uart_port *port,
176				 unsigned int mctrl)
177{
178/*
179 * Even if we do not support configuring the modem control lines, this
180 * function must be proided to the serial core
181 */
182}
183
184static void mvebu_uart_stop_tx(struct uart_port *port)
185{
186	unsigned int ctl = readl(port->membase + UART_INTR(port));
187
188	ctl &= ~CTRL_TX_RDY_INT(port);
189	writel(ctl, port->membase + UART_INTR(port));
190}
191
192static void mvebu_uart_start_tx(struct uart_port *port)
193{
194	unsigned int ctl;
195	struct circ_buf *xmit = &port->state->xmit;
196
197	if (IS_EXTENDED(port) && !uart_circ_empty(xmit)) {
198		writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port));
199		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
200		port->icount.tx++;
201	}
202
203	ctl = readl(port->membase + UART_INTR(port));
204	ctl |= CTRL_TX_RDY_INT(port);
205	writel(ctl, port->membase + UART_INTR(port));
206}
207
208static void mvebu_uart_stop_rx(struct uart_port *port)
209{
210	unsigned int ctl;
211
212	ctl = readl(port->membase + UART_CTRL(port));
213	ctl &= ~CTRL_BRK_INT;
214	writel(ctl, port->membase + UART_CTRL(port));
215
216	ctl = readl(port->membase + UART_INTR(port));
217	ctl &= ~CTRL_RX_RDY_INT(port);
218	writel(ctl, port->membase + UART_INTR(port));
219}
220
221static void mvebu_uart_break_ctl(struct uart_port *port, int brk)
222{
223	unsigned int ctl;
224	unsigned long flags;
225
226	spin_lock_irqsave(&port->lock, flags);
227	ctl = readl(port->membase + UART_CTRL(port));
228	if (brk == -1)
229		ctl |= CTRL_SND_BRK_SEQ;
230	else
231		ctl &= ~CTRL_SND_BRK_SEQ;
232	writel(ctl, port->membase + UART_CTRL(port));
233	spin_unlock_irqrestore(&port->lock, flags);
234}
235
236static void mvebu_uart_rx_chars(struct uart_port *port, unsigned int status)
237{
238	struct tty_port *tport = &port->state->port;
239	unsigned char ch = 0;
240	char flag = 0;
241
242	do {
243		if (status & STAT_RX_RDY(port)) {
244			ch = readl(port->membase + UART_RBR(port));
245			ch &= 0xff;
246			flag = TTY_NORMAL;
247			port->icount.rx++;
248
249			if (status & STAT_PAR_ERR)
250				port->icount.parity++;
251		}
252
253		if (status & STAT_BRK_DET) {
254			port->icount.brk++;
255			status &= ~(STAT_FRM_ERR | STAT_PAR_ERR);
256			if (uart_handle_break(port))
257				goto ignore_char;
258		}
259
260		if (status & STAT_OVR_ERR)
261			port->icount.overrun++;
262
263		if (status & STAT_FRM_ERR)
264			port->icount.frame++;
265
266		if (uart_handle_sysrq_char(port, ch))
267			goto ignore_char;
268
269		if (status & port->ignore_status_mask & STAT_PAR_ERR)
270			status &= ~STAT_RX_RDY(port);
271
272		status &= port->read_status_mask;
273
274		if (status & STAT_PAR_ERR)
275			flag = TTY_PARITY;
276
277		status &= ~port->ignore_status_mask;
278
279		if (status & STAT_RX_RDY(port))
280			tty_insert_flip_char(tport, ch, flag);
281
282		if (status & STAT_BRK_DET)
283			tty_insert_flip_char(tport, 0, TTY_BREAK);
284
285		if (status & STAT_FRM_ERR)
286			tty_insert_flip_char(tport, 0, TTY_FRAME);
287
288		if (status & STAT_OVR_ERR)
289			tty_insert_flip_char(tport, 0, TTY_OVERRUN);
290
291ignore_char:
292		status = readl(port->membase + UART_STAT);
293	} while (status & (STAT_RX_RDY(port) | STAT_BRK_DET));
294
295	tty_flip_buffer_push(tport);
296}
297
298static void mvebu_uart_tx_chars(struct uart_port *port, unsigned int status)
299{
300	struct circ_buf *xmit = &port->state->xmit;
301	unsigned int count;
302	unsigned int st;
303
304	if (port->x_char) {
305		writel(port->x_char, port->membase + UART_TSH(port));
306		port->icount.tx++;
307		port->x_char = 0;
308		return;
309	}
310
311	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
312		mvebu_uart_stop_tx(port);
313		return;
314	}
315
316	for (count = 0; count < port->fifosize; count++) {
317		writel(xmit->buf[xmit->tail], port->membase + UART_TSH(port));
318		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
319		port->icount.tx++;
320
321		if (uart_circ_empty(xmit))
322			break;
323
324		st = readl(port->membase + UART_STAT);
325		if (st & STAT_TX_FIFO_FUL)
326			break;
327	}
328
329	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
330		uart_write_wakeup(port);
331
332	if (uart_circ_empty(xmit))
333		mvebu_uart_stop_tx(port);
334}
335
336static irqreturn_t mvebu_uart_isr(int irq, void *dev_id)
337{
338	struct uart_port *port = (struct uart_port *)dev_id;
339	unsigned int st = readl(port->membase + UART_STAT);
340
341	if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR |
342		  STAT_BRK_DET))
343		mvebu_uart_rx_chars(port, st);
344
345	if (st & STAT_TX_RDY(port))
346		mvebu_uart_tx_chars(port, st);
347
348	return IRQ_HANDLED;
349}
350
351static irqreturn_t mvebu_uart_rx_isr(int irq, void *dev_id)
352{
353	struct uart_port *port = (struct uart_port *)dev_id;
354	unsigned int st = readl(port->membase + UART_STAT);
355
356	if (st & (STAT_RX_RDY(port) | STAT_OVR_ERR | STAT_FRM_ERR |
357			STAT_BRK_DET))
358		mvebu_uart_rx_chars(port, st);
359
360	return IRQ_HANDLED;
361}
362
363static irqreturn_t mvebu_uart_tx_isr(int irq, void *dev_id)
364{
365	struct uart_port *port = (struct uart_port *)dev_id;
366	unsigned int st = readl(port->membase + UART_STAT);
367
368	if (st & STAT_TX_RDY(port))
369		mvebu_uart_tx_chars(port, st);
370
371	return IRQ_HANDLED;
372}
373
374static int mvebu_uart_startup(struct uart_port *port)
375{
376	struct mvebu_uart *mvuart = to_mvuart(port);
377	unsigned int ctl;
378	int ret;
379
380	writel(CTRL_TXFIFO_RST | CTRL_RXFIFO_RST,
381	       port->membase + UART_CTRL(port));
382	udelay(1);
383
384	/* Clear the error bits of state register before IRQ request */
385	ret = readl(port->membase + UART_STAT);
386	ret |= STAT_BRK_ERR;
387	writel(ret, port->membase + UART_STAT);
388
389	writel(CTRL_BRK_INT, port->membase + UART_CTRL(port));
390
391	ctl = readl(port->membase + UART_INTR(port));
392	ctl |= CTRL_RX_RDY_INT(port);
393	writel(ctl, port->membase + UART_INTR(port));
394
395	if (!mvuart->irq[UART_TX_IRQ]) {
396		/* Old bindings with just one interrupt (UART0 only) */
397		ret = devm_request_irq(port->dev, mvuart->irq[UART_IRQ_SUM],
398				       mvebu_uart_isr, port->irqflags,
399				       dev_name(port->dev), port);
400		if (ret) {
401			dev_err(port->dev, "unable to request IRQ %d\n",
402				mvuart->irq[UART_IRQ_SUM]);
403			return ret;
404		}
405	} else {
406		/* New bindings with an IRQ for RX and TX (both UART) */
407		ret = devm_request_irq(port->dev, mvuart->irq[UART_RX_IRQ],
408				       mvebu_uart_rx_isr, port->irqflags,
409				       dev_name(port->dev), port);
410		if (ret) {
411			dev_err(port->dev, "unable to request IRQ %d\n",
412				mvuart->irq[UART_RX_IRQ]);
413			return ret;
414		}
415
416		ret = devm_request_irq(port->dev, mvuart->irq[UART_TX_IRQ],
417				       mvebu_uart_tx_isr, port->irqflags,
418				       dev_name(port->dev),
419				       port);
420		if (ret) {
421			dev_err(port->dev, "unable to request IRQ %d\n",
422				mvuart->irq[UART_TX_IRQ]);
423			devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ],
424				      port);
425			return ret;
426		}
427	}
428
429	return 0;
430}
431
432static void mvebu_uart_shutdown(struct uart_port *port)
433{
434	struct mvebu_uart *mvuart = to_mvuart(port);
435
436	writel(0, port->membase + UART_INTR(port));
437
438	if (!mvuart->irq[UART_TX_IRQ]) {
439		devm_free_irq(port->dev, mvuart->irq[UART_IRQ_SUM], port);
440	} else {
441		devm_free_irq(port->dev, mvuart->irq[UART_RX_IRQ], port);
442		devm_free_irq(port->dev, mvuart->irq[UART_TX_IRQ], port);
443	}
444}
445
446static int mvebu_uart_baud_rate_set(struct uart_port *port, unsigned int baud)
447{
448	struct mvebu_uart *mvuart = to_mvuart(port);
449	unsigned int d_divisor, m_divisor;
450	u32 brdv, osamp;
451
452	if (IS_ERR(mvuart->clk))
453		return -PTR_ERR(mvuart->clk);
454
455	/*
456	 * The baudrate is derived from the UART clock thanks to two divisors:
457	 *   > D ("baud generator"): can divide the clock from 2 to 2^10 - 1.
458	 *   > M ("fractional divisor"): allows a better accuracy for
459	 *     baudrates higher than 230400.
460	 *
461	 * As the derivation of M is rather complicated, the code sticks to its
462	 * default value (x16) when all the prescalers are zeroed, and only
463	 * makes use of D to configure the desired baudrate.
464	 */
465	m_divisor = OSAMP_DEFAULT_DIVISOR;
466	d_divisor = DIV_ROUND_UP(port->uartclk, baud * m_divisor);
467
468	brdv = readl(port->membase + UART_BRDV);
469	brdv &= ~BRDV_BAUD_MASK;
470	brdv |= d_divisor;
471	writel(brdv, port->membase + UART_BRDV);
472
473	osamp = readl(port->membase + UART_OSAMP);
474	osamp &= ~OSAMP_DIVISORS_MASK;
475	writel(osamp, port->membase + UART_OSAMP);
476
477	return 0;
478}
479
480static void mvebu_uart_set_termios(struct uart_port *port,
481				   struct ktermios *termios,
482				   struct ktermios *old)
483{
484	unsigned long flags;
485	unsigned int baud;
486
487	spin_lock_irqsave(&port->lock, flags);
488
489	port->read_status_mask = STAT_RX_RDY(port) | STAT_OVR_ERR |
490		STAT_TX_RDY(port) | STAT_TX_FIFO_FUL;
491
492	if (termios->c_iflag & INPCK)
493		port->read_status_mask |= STAT_FRM_ERR | STAT_PAR_ERR;
494
495	port->ignore_status_mask = 0;
496	if (termios->c_iflag & IGNPAR)
497		port->ignore_status_mask |=
498			STAT_FRM_ERR | STAT_PAR_ERR | STAT_OVR_ERR;
499
500	if ((termios->c_cflag & CREAD) == 0)
501		port->ignore_status_mask |= STAT_RX_RDY(port) | STAT_BRK_ERR;
502
503	/*
504	 * Maximum achievable frequency with simple baudrate divisor is 230400.
505	 * Since the error per bit frame would be of more than 15%, achieving
506	 * higher frequencies would require to implement the fractional divisor
507	 * feature.
508	 */
509	baud = uart_get_baud_rate(port, termios, old, 0, 230400);
510	if (mvebu_uart_baud_rate_set(port, baud)) {
511		/* No clock available, baudrate cannot be changed */
512		if (old)
513			baud = uart_get_baud_rate(port, old, NULL, 0, 230400);
514	} else {
515		tty_termios_encode_baud_rate(termios, baud, baud);
516		uart_update_timeout(port, termios->c_cflag, baud);
517	}
518
519	/* Only the following flag changes are supported */
520	if (old) {
521		termios->c_iflag &= INPCK | IGNPAR;
522		termios->c_iflag |= old->c_iflag & ~(INPCK | IGNPAR);
523		termios->c_cflag &= CREAD | CBAUD;
524		termios->c_cflag |= old->c_cflag & ~(CREAD | CBAUD);
525		termios->c_cflag |= CS8;
526	}
527
528	spin_unlock_irqrestore(&port->lock, flags);
529}
530
531static const char *mvebu_uart_type(struct uart_port *port)
532{
533	return MVEBU_UART_TYPE;
534}
535
536static void mvebu_uart_release_port(struct uart_port *port)
537{
538	/* Nothing to do here */
539}
540
541static int mvebu_uart_request_port(struct uart_port *port)
542{
543	return 0;
544}
545
546#ifdef CONFIG_CONSOLE_POLL
547static int mvebu_uart_get_poll_char(struct uart_port *port)
548{
549	unsigned int st = readl(port->membase + UART_STAT);
550
551	if (!(st & STAT_RX_RDY(port)))
552		return NO_POLL_CHAR;
553
554	return readl(port->membase + UART_RBR(port));
555}
556
557static void mvebu_uart_put_poll_char(struct uart_port *port, unsigned char c)
558{
559	unsigned int st;
560
561	for (;;) {
562		st = readl(port->membase + UART_STAT);
563
564		if (!(st & STAT_TX_FIFO_FUL))
565			break;
566
567		udelay(1);
568	}
569
570	writel(c, port->membase + UART_TSH(port));
571}
572#endif
573
574static const struct uart_ops mvebu_uart_ops = {
575	.tx_empty	= mvebu_uart_tx_empty,
576	.set_mctrl	= mvebu_uart_set_mctrl,
577	.get_mctrl	= mvebu_uart_get_mctrl,
578	.stop_tx	= mvebu_uart_stop_tx,
579	.start_tx	= mvebu_uart_start_tx,
580	.stop_rx	= mvebu_uart_stop_rx,
581	.break_ctl	= mvebu_uart_break_ctl,
582	.startup	= mvebu_uart_startup,
583	.shutdown	= mvebu_uart_shutdown,
584	.set_termios	= mvebu_uart_set_termios,
585	.type		= mvebu_uart_type,
586	.release_port	= mvebu_uart_release_port,
587	.request_port	= mvebu_uart_request_port,
588#ifdef CONFIG_CONSOLE_POLL
589	.poll_get_char	= mvebu_uart_get_poll_char,
590	.poll_put_char	= mvebu_uart_put_poll_char,
591#endif
592};
593
594/* Console Driver Operations  */
595
596#ifdef CONFIG_SERIAL_MVEBU_CONSOLE
597/* Early Console */
598static void mvebu_uart_putc(struct uart_port *port, int c)
599{
600	unsigned int st;
601
602	for (;;) {
603		st = readl(port->membase + UART_STAT);
604		if (!(st & STAT_TX_FIFO_FUL))
605			break;
606	}
607
608	/* At early stage, DT is not parsed yet, only use UART0 */
609	writel(c, port->membase + UART_STD_TSH);
610
611	for (;;) {
612		st = readl(port->membase + UART_STAT);
613		if (st & STAT_TX_FIFO_EMP)
614			break;
615	}
616}
617
618static void mvebu_uart_putc_early_write(struct console *con,
619					const char *s,
620					unsigned n)
621{
622	struct earlycon_device *dev = con->data;
623
624	uart_console_write(&dev->port, s, n, mvebu_uart_putc);
625}
626
627static int __init
628mvebu_uart_early_console_setup(struct earlycon_device *device,
629			       const char *opt)
630{
631	if (!device->port.membase)
632		return -ENODEV;
633
634	device->con->write = mvebu_uart_putc_early_write;
635
636	return 0;
637}
638
639EARLYCON_DECLARE(ar3700_uart, mvebu_uart_early_console_setup);
640OF_EARLYCON_DECLARE(ar3700_uart, "marvell,armada-3700-uart",
641		    mvebu_uart_early_console_setup);
642
643static void wait_for_xmitr(struct uart_port *port)
644{
645	u32 val;
646
647	readl_poll_timeout_atomic(port->membase + UART_STAT, val,
648				  (val & STAT_TX_RDY(port)), 1, 10000);
649}
650
651static void mvebu_uart_console_putchar(struct uart_port *port, int ch)
652{
653	wait_for_xmitr(port);
654	writel(ch, port->membase + UART_TSH(port));
655}
656
657static void mvebu_uart_console_write(struct console *co, const char *s,
658				     unsigned int count)
659{
660	struct uart_port *port = &mvebu_uart_ports[co->index];
661	unsigned long flags;
662	unsigned int ier, intr, ctl;
663	int locked = 1;
664
665	if (oops_in_progress)
666		locked = spin_trylock_irqsave(&port->lock, flags);
667	else
668		spin_lock_irqsave(&port->lock, flags);
669
670	ier = readl(port->membase + UART_CTRL(port)) & CTRL_BRK_INT;
671	intr = readl(port->membase + UART_INTR(port)) &
672		(CTRL_RX_RDY_INT(port) | CTRL_TX_RDY_INT(port));
673	writel(0, port->membase + UART_CTRL(port));
674	writel(0, port->membase + UART_INTR(port));
675
676	uart_console_write(port, s, count, mvebu_uart_console_putchar);
677
678	wait_for_xmitr(port);
679
680	if (ier)
681		writel(ier, port->membase + UART_CTRL(port));
682
683	if (intr) {
684		ctl = intr | readl(port->membase + UART_INTR(port));
685		writel(ctl, port->membase + UART_INTR(port));
686	}
687
688	if (locked)
689		spin_unlock_irqrestore(&port->lock, flags);
690}
691
692static int mvebu_uart_console_setup(struct console *co, char *options)
693{
694	struct uart_port *port;
695	int baud = 9600;
696	int bits = 8;
697	int parity = 'n';
698	int flow = 'n';
699
700	if (co->index < 0 || co->index >= MVEBU_NR_UARTS)
701		return -EINVAL;
702
703	port = &mvebu_uart_ports[co->index];
704
705	if (!port->mapbase || !port->membase) {
706		pr_debug("console on ttyMV%i not present\n", co->index);
707		return -ENODEV;
708	}
709
710	if (options)
711		uart_parse_options(options, &baud, &parity, &bits, &flow);
712
713	return uart_set_options(port, co, baud, parity, bits, flow);
714}
715
716static struct uart_driver mvebu_uart_driver;
717
718static struct console mvebu_uart_console = {
719	.name	= "ttyMV",
720	.write	= mvebu_uart_console_write,
721	.device	= uart_console_device,
722	.setup	= mvebu_uart_console_setup,
723	.flags	= CON_PRINTBUFFER,
724	.index	= -1,
725	.data	= &mvebu_uart_driver,
726};
727
728static int __init mvebu_uart_console_init(void)
729{
730	register_console(&mvebu_uart_console);
731	return 0;
732}
733
734console_initcall(mvebu_uart_console_init);
735
736
737#endif /* CONFIG_SERIAL_MVEBU_CONSOLE */
738
739static struct uart_driver mvebu_uart_driver = {
740	.owner			= THIS_MODULE,
741	.driver_name		= DRIVER_NAME,
742	.dev_name		= "ttyMV",
743	.nr			= MVEBU_NR_UARTS,
744#ifdef CONFIG_SERIAL_MVEBU_CONSOLE
745	.cons			= &mvebu_uart_console,
746#endif
747};
748
749#if defined(CONFIG_PM)
750static int mvebu_uart_suspend(struct device *dev)
751{
752	struct mvebu_uart *mvuart = dev_get_drvdata(dev);
753	struct uart_port *port = mvuart->port;
754
755	uart_suspend_port(&mvebu_uart_driver, port);
756
757	mvuart->pm_regs.rbr = readl(port->membase + UART_RBR(port));
758	mvuart->pm_regs.tsh = readl(port->membase + UART_TSH(port));
759	mvuart->pm_regs.ctrl = readl(port->membase + UART_CTRL(port));
760	mvuart->pm_regs.intr = readl(port->membase + UART_INTR(port));
761	mvuart->pm_regs.stat = readl(port->membase + UART_STAT);
762	mvuart->pm_regs.brdv = readl(port->membase + UART_BRDV);
763	mvuart->pm_regs.osamp = readl(port->membase + UART_OSAMP);
764
765	device_set_wakeup_enable(dev, true);
766
767	return 0;
768}
769
770static int mvebu_uart_resume(struct device *dev)
771{
772	struct mvebu_uart *mvuart = dev_get_drvdata(dev);
773	struct uart_port *port = mvuart->port;
774
775	writel(mvuart->pm_regs.rbr, port->membase + UART_RBR(port));
776	writel(mvuart->pm_regs.tsh, port->membase + UART_TSH(port));
777	writel(mvuart->pm_regs.ctrl, port->membase + UART_CTRL(port));
778	writel(mvuart->pm_regs.intr, port->membase + UART_INTR(port));
779	writel(mvuart->pm_regs.stat, port->membase + UART_STAT);
780	writel(mvuart->pm_regs.brdv, port->membase + UART_BRDV);
781	writel(mvuart->pm_regs.osamp, port->membase + UART_OSAMP);
782
783	uart_resume_port(&mvebu_uart_driver, port);
784
785	return 0;
786}
787
788static const struct dev_pm_ops mvebu_uart_pm_ops = {
789	.suspend        = mvebu_uart_suspend,
790	.resume         = mvebu_uart_resume,
791};
792#endif /* CONFIG_PM */
793
794static const struct of_device_id mvebu_uart_of_match[];
795
796/* Counter to keep track of each UART port id when not using CONFIG_OF */
797static int uart_num_counter;
798
799static int mvebu_uart_probe(struct platform_device *pdev)
800{
801	struct resource *reg = platform_get_resource(pdev, IORESOURCE_MEM, 0);
802	const struct of_device_id *match = of_match_device(mvebu_uart_of_match,
803							   &pdev->dev);
804	struct uart_port *port;
805	struct mvebu_uart *mvuart;
806	int ret, id, irq;
807
808	if (!reg) {
809		dev_err(&pdev->dev, "no registers defined\n");
810		return -EINVAL;
811	}
812
813	if (!match)
814		return -ENODEV;
815
816	/* Assume that all UART ports have a DT alias or none has */
817	id = of_alias_get_id(pdev->dev.of_node, "serial");
818	if (!pdev->dev.of_node || id < 0)
819		pdev->id = uart_num_counter++;
820	else
821		pdev->id = id;
822
823	if (pdev->id >= MVEBU_NR_UARTS) {
824		dev_err(&pdev->dev, "cannot have more than %d UART ports\n",
825			MVEBU_NR_UARTS);
826		return -EINVAL;
827	}
828
829	port = &mvebu_uart_ports[pdev->id];
830
831	spin_lock_init(&port->lock);
832
833	port->dev        = &pdev->dev;
834	port->type       = PORT_MVEBU;
835	port->ops        = &mvebu_uart_ops;
836	port->regshift   = 0;
837
838	port->fifosize   = 32;
839	port->iotype     = UPIO_MEM32;
840	port->flags      = UPF_FIXED_PORT;
841	port->line       = pdev->id;
842
843	/*
844	 * IRQ number is not stored in this structure because we may have two of
845	 * them per port (RX and TX). Instead, use the driver UART structure
846	 * array so called ->irq[].
847	 */
848	port->irq        = 0;
849	port->irqflags   = 0;
850	port->mapbase    = reg->start;
851
852	port->membase = devm_ioremap_resource(&pdev->dev, reg);
853	if (IS_ERR(port->membase))
854		return -PTR_ERR(port->membase);
855
856	mvuart = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_uart),
857			      GFP_KERNEL);
858	if (!mvuart)
859		return -ENOMEM;
860
861	/* Get controller data depending on the compatible string */
862	mvuart->data = (struct mvebu_uart_driver_data *)match->data;
863	mvuart->port = port;
864
865	port->private_data = mvuart;
866	platform_set_drvdata(pdev, mvuart);
867
868	/* Get fixed clock frequency */
869	mvuart->clk = devm_clk_get(&pdev->dev, NULL);
870	if (IS_ERR(mvuart->clk)) {
871		if (PTR_ERR(mvuart->clk) == -EPROBE_DEFER)
872			return PTR_ERR(mvuart->clk);
873
874		if (IS_EXTENDED(port)) {
875			dev_err(&pdev->dev, "unable to get UART clock\n");
876			return PTR_ERR(mvuart->clk);
877		}
878	} else {
879		if (!clk_prepare_enable(mvuart->clk))
880			port->uartclk = clk_get_rate(mvuart->clk);
881	}
882
883	/* Manage interrupts */
884	if (platform_irq_count(pdev) == 1) {
885		/* Old bindings: no name on the single unamed UART0 IRQ */
886		irq = platform_get_irq(pdev, 0);
887		if (irq < 0)
888			return irq;
889
890		mvuart->irq[UART_IRQ_SUM] = irq;
891	} else {
892		/*
893		 * New bindings: named interrupts (RX, TX) for both UARTS,
894		 * only make use of uart-rx and uart-tx interrupts, do not use
895		 * uart-sum of UART0 port.
896		 */
897		irq = platform_get_irq_byname(pdev, "uart-rx");
898		if (irq < 0)
899			return irq;
900
901		mvuart->irq[UART_RX_IRQ] = irq;
902
903		irq = platform_get_irq_byname(pdev, "uart-tx");
904		if (irq < 0)
905			return irq;
906
907		mvuart->irq[UART_TX_IRQ] = irq;
908	}
909
910	/* UART Soft Reset*/
911	writel(CTRL_SOFT_RST, port->membase + UART_CTRL(port));
912	udelay(1);
913	writel(0, port->membase + UART_CTRL(port));
914
915	ret = uart_add_one_port(&mvebu_uart_driver, port);
916	if (ret)
917		return ret;
918	return 0;
919}
920
921static struct mvebu_uart_driver_data uart_std_driver_data = {
922	.is_ext = false,
923	.regs.rbr = UART_STD_RBR,
924	.regs.tsh = UART_STD_TSH,
925	.regs.ctrl = UART_STD_CTRL1,
926	.regs.intr = UART_STD_CTRL2,
927	.flags.ctrl_tx_rdy_int = CTRL_STD_TX_RDY_INT,
928	.flags.ctrl_rx_rdy_int = CTRL_STD_RX_RDY_INT,
929	.flags.stat_tx_rdy = STAT_STD_TX_RDY,
930	.flags.stat_rx_rdy = STAT_STD_RX_RDY,
931};
932
933static struct mvebu_uart_driver_data uart_ext_driver_data = {
934	.is_ext = true,
935	.regs.rbr = UART_EXT_RBR,
936	.regs.tsh = UART_EXT_TSH,
937	.regs.ctrl = UART_EXT_CTRL1,
938	.regs.intr = UART_EXT_CTRL2,
939	.flags.ctrl_tx_rdy_int = CTRL_EXT_TX_RDY_INT,
940	.flags.ctrl_rx_rdy_int = CTRL_EXT_RX_RDY_INT,
941	.flags.stat_tx_rdy = STAT_EXT_TX_RDY,
942	.flags.stat_rx_rdy = STAT_EXT_RX_RDY,
943};
944
945/* Match table for of_platform binding */
946static const struct of_device_id mvebu_uart_of_match[] = {
947	{
948		.compatible = "marvell,armada-3700-uart",
949		.data = (void *)&uart_std_driver_data,
950	},
951	{
952		.compatible = "marvell,armada-3700-uart-ext",
953		.data = (void *)&uart_ext_driver_data,
954	},
955	{}
956};
957
958static struct platform_driver mvebu_uart_platform_driver = {
959	.probe	= mvebu_uart_probe,
960	.driver	= {
961		.name  = "mvebu-uart",
962		.of_match_table = of_match_ptr(mvebu_uart_of_match),
963		.suppress_bind_attrs = true,
964#if defined(CONFIG_PM)
965		.pm	= &mvebu_uart_pm_ops,
966#endif /* CONFIG_PM */
967	},
968};
969
970static int __init mvebu_uart_init(void)
971{
972	int ret;
973
974	ret = uart_register_driver(&mvebu_uart_driver);
975	if (ret)
976		return ret;
977
978	ret = platform_driver_register(&mvebu_uart_platform_driver);
979	if (ret)
980		uart_unregister_driver(&mvebu_uart_driver);
981
982	return ret;
983}
984arch_initcall(mvebu_uart_init);