1/*
2 * Driver for msm7k serial device and console
3 *
4 * Copyright (C) 2007 Google, Inc.
5 * Author: Robert Love <rlove@google.com>
6 * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
7 *
8 * This software is licensed under the terms of the GNU General Public
9 * License version 2, as published by the Free Software Foundation, and
10 * may be copied, distributed, and modified under those terms.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 */
17
18#if defined(CONFIG_SERIAL_MSM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
19# define SUPPORT_SYSRQ
20#endif
21
22#include <linux/atomic.h>
23#include <linux/dma-mapping.h>
24#include <linux/dmaengine.h>
25#include <linux/hrtimer.h>
26#include <linux/module.h>
27#include <linux/io.h>
28#include <linux/ioport.h>
29#include <linux/irq.h>
30#include <linux/init.h>
31#include <linux/console.h>
32#include <linux/tty.h>
33#include <linux/tty_flip.h>
34#include <linux/serial_core.h>
35#include <linux/serial.h>
36#include <linux/slab.h>
37#include <linux/clk.h>
38#include <linux/platform_device.h>
39#include <linux/delay.h>
40#include <linux/of.h>
41#include <linux/of_device.h>
42
43#include "msm_serial.h"
44
45#define UARTDM_BURST_SIZE	16   /* in bytes */
46#define UARTDM_TX_AIGN(x)	((x) & ~0x3) /* valid for > 1p3 */
47#define UARTDM_TX_MAX		256   /* in bytes, valid for <= 1p3 */
48#define UARTDM_RX_SIZE		(UART_XMIT_SIZE / 4)
49
50enum {
51	UARTDM_1P1 = 1,
52	UARTDM_1P2,
53	UARTDM_1P3,
54	UARTDM_1P4,
55};
56
57struct msm_dma {
58	struct dma_chan		*chan;
59	enum dma_data_direction dir;
60	dma_addr_t		phys;
61	unsigned char		*virt;
62	dma_cookie_t		cookie;
63	u32			enable_bit;
64	unsigned int		count;
65	struct dma_async_tx_descriptor	*desc;
66};
67
68struct msm_port {
69	struct uart_port	uart;
70	char			name[16];
71	struct clk		*clk;
72	struct clk		*pclk;
73	unsigned int		imr;
74	int			is_uartdm;
75	unsigned int		old_snap_state;
76	bool			break_detected;
77	struct msm_dma		tx_dma;
78	struct msm_dma		rx_dma;
79};
80
81static void msm_handle_tx(struct uart_port *port);
82static void msm_start_rx_dma(struct msm_port *msm_port);
83
84void msm_stop_dma(struct uart_port *port, struct msm_dma *dma)
85{
86	struct device *dev = port->dev;
87	unsigned int mapped;
88	u32 val;
89
90	mapped = dma->count;
91	dma->count = 0;
92
93	dmaengine_terminate_all(dma->chan);
94
95	/*
96	 * DMA Stall happens if enqueue and flush command happens concurrently.
97	 * For example before changing the baud rate/protocol configuration and
98	 * sending flush command to ADM, disable the channel of UARTDM.
99	 * Note: should not reset the receiver here immediately as it is not
100	 * suggested to do disable/reset or reset/disable at the same time.
101	 */
102	val = msm_read(port, UARTDM_DMEN);
103	val &= ~dma->enable_bit;
104	msm_write(port, val, UARTDM_DMEN);
105
106	if (mapped)
107		dma_unmap_single(dev, dma->phys, mapped, dma->dir);
108}
109
110static void msm_release_dma(struct msm_port *msm_port)
111{
112	struct msm_dma *dma;
113
114	dma = &msm_port->tx_dma;
115	if (dma->chan) {
116		msm_stop_dma(&msm_port->uart, dma);
117		dma_release_channel(dma->chan);
118	}
119
120	memset(dma, 0, sizeof(*dma));
121
122	dma = &msm_port->rx_dma;
123	if (dma->chan) {
124		msm_stop_dma(&msm_port->uart, dma);
125		dma_release_channel(dma->chan);
126		kfree(dma->virt);
127	}
128
129	memset(dma, 0, sizeof(*dma));
130}
131
132static void msm_request_tx_dma(struct msm_port *msm_port, resource_size_t base)
133{
134	struct device *dev = msm_port->uart.dev;
135	struct dma_slave_config conf;
136	struct msm_dma *dma;
137	u32 crci = 0;
138	int ret;
139
140	dma = &msm_port->tx_dma;
141
142	/* allocate DMA resources, if available */
143	dma->chan = dma_request_slave_channel_reason(dev, "tx");
144	if (IS_ERR(dma->chan))
145		goto no_tx;
146
147	of_property_read_u32(dev->of_node, "qcom,tx-crci", &crci);
148
149	memset(&conf, 0, sizeof(conf));
150	conf.direction = DMA_MEM_TO_DEV;
151	conf.device_fc = true;
152	conf.dst_addr = base + UARTDM_TF;
153	conf.dst_maxburst = UARTDM_BURST_SIZE;
154	conf.slave_id = crci;
155
156	ret = dmaengine_slave_config(dma->chan, &conf);
157	if (ret)
158		goto rel_tx;
159
160	dma->dir = DMA_TO_DEVICE;
161
162	if (msm_port->is_uartdm < UARTDM_1P4)
163		dma->enable_bit = UARTDM_DMEN_TX_DM_ENABLE;
164	else
165		dma->enable_bit = UARTDM_DMEN_TX_BAM_ENABLE;
166
167	return;
168
169rel_tx:
170	dma_release_channel(dma->chan);
171no_tx:
172	memset(dma, 0, sizeof(*dma));
173}
174
175static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
176{
177	struct device *dev = msm_port->uart.dev;
178	struct dma_slave_config conf;
179	struct msm_dma *dma;
180	u32 crci = 0;
181	int ret;
182
183	dma = &msm_port->rx_dma;
184
185	/* allocate DMA resources, if available */
186	dma->chan = dma_request_slave_channel_reason(dev, "rx");
187	if (IS_ERR(dma->chan))
188		goto no_rx;
189
190	of_property_read_u32(dev->of_node, "qcom,rx-crci", &crci);
191
192	dma->virt = kzalloc(UARTDM_RX_SIZE, GFP_KERNEL);
193	if (!dma->virt)
194		goto rel_rx;
195
196	memset(&conf, 0, sizeof(conf));
197	conf.direction = DMA_DEV_TO_MEM;
198	conf.device_fc = true;
199	conf.src_addr = base + UARTDM_RF;
200	conf.src_maxburst = UARTDM_BURST_SIZE;
201	conf.slave_id = crci;
202
203	ret = dmaengine_slave_config(dma->chan, &conf);
204	if (ret)
205		goto err;
206
207	dma->dir = DMA_FROM_DEVICE;
208
209	if (msm_port->is_uartdm < UARTDM_1P4)
210		dma->enable_bit = UARTDM_DMEN_RX_DM_ENABLE;
211	else
212		dma->enable_bit = UARTDM_DMEN_RX_BAM_ENABLE;
213
214	return;
215err:
216	kfree(dma->virt);
217rel_rx:
218	dma_release_channel(dma->chan);
219no_rx:
220	memset(dma, 0, sizeof(*dma));
221}
222
223static inline void msm_wait_for_xmitr(struct uart_port *port)
224{
225	while (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY)) {
226		if (msm_read(port, UART_ISR) & UART_ISR_TX_READY)
227			break;
228		udelay(1);
229	}
230	msm_write(port, UART_CR_CMD_RESET_TX_READY, UART_CR);
231}
232
233static void msm_stop_tx(struct uart_port *port)
234{
235	struct msm_port *msm_port = UART_TO_MSM(port);
236
237	msm_port->imr &= ~UART_IMR_TXLEV;
238	msm_write(port, msm_port->imr, UART_IMR);
239}
240
241static void msm_start_tx(struct uart_port *port)
242{
243	struct msm_port *msm_port = UART_TO_MSM(port);
244	struct msm_dma *dma = &msm_port->tx_dma;
245
246	/* Already started in DMA mode */
247	if (dma->count)
248		return;
249
250	msm_port->imr |= UART_IMR_TXLEV;
251	msm_write(port, msm_port->imr, UART_IMR);
252}
253
254static void msm_reset_dm_count(struct uart_port *port, int count)
255{
256	msm_wait_for_xmitr(port);
257	msm_write(port, count, UARTDM_NCF_TX);
258	msm_read(port, UARTDM_NCF_TX);
259}
260
261static void msm_complete_tx_dma(void *args)
262{
263	struct msm_port *msm_port = args;
264	struct uart_port *port = &msm_port->uart;
265	struct circ_buf *xmit = &port->state->xmit;
266	struct msm_dma *dma = &msm_port->tx_dma;
267	struct dma_tx_state state;
268	enum dma_status status;
269	unsigned long flags;
270	unsigned int count;
271	u32 val;
272
273	spin_lock_irqsave(&port->lock, flags);
274
275	/* Already stopped */
276	if (!dma->count)
277		goto done;
278
279	status = dmaengine_tx_status(dma->chan, dma->cookie, &state);
280
281	dma_unmap_single(port->dev, dma->phys, dma->count, dma->dir);
282
283	val = msm_read(port, UARTDM_DMEN);
284	val &= ~dma->enable_bit;
285	msm_write(port, val, UARTDM_DMEN);
286
287	if (msm_port->is_uartdm > UARTDM_1P3) {
288		msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
289		msm_write(port, UART_CR_TX_ENABLE, UART_CR);
290	}
291
292	count = dma->count - state.residue;
293	port->icount.tx += count;
294	dma->count = 0;
295
296	xmit->tail += count;
297	xmit->tail &= UART_XMIT_SIZE - 1;
298
299	/* Restore "Tx FIFO below watermark" interrupt */
300	msm_port->imr |= UART_IMR_TXLEV;
301	msm_write(port, msm_port->imr, UART_IMR);
302
303	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
304		uart_write_wakeup(port);
305
306	msm_handle_tx(port);
307done:
308	spin_unlock_irqrestore(&port->lock, flags);
309}
310
311static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
312{
313	struct circ_buf *xmit = &msm_port->uart.state->xmit;
314	struct uart_port *port = &msm_port->uart;
315	struct msm_dma *dma = &msm_port->tx_dma;
316	void *cpu_addr;
317	int ret;
318	u32 val;
319
320	cpu_addr = &xmit->buf[xmit->tail];
321
322	dma->phys = dma_map_single(port->dev, cpu_addr, count, dma->dir);
323	ret = dma_mapping_error(port->dev, dma->phys);
324	if (ret)
325		return ret;
326
327	dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
328						count, DMA_MEM_TO_DEV,
329						DMA_PREP_INTERRUPT |
330						DMA_PREP_FENCE);
331	if (!dma->desc) {
332		ret = -EIO;
333		goto unmap;
334	}
335
336	dma->desc->callback = msm_complete_tx_dma;
337	dma->desc->callback_param = msm_port;
338
339	dma->cookie = dmaengine_submit(dma->desc);
340	ret = dma_submit_error(dma->cookie);
341	if (ret)
342		goto unmap;
343
344	/*
345	 * Using DMA complete for Tx FIFO reload, no need for
346	 * "Tx FIFO below watermark" one, disable it
347	 */
348	msm_port->imr &= ~UART_IMR_TXLEV;
349	msm_write(port, msm_port->imr, UART_IMR);
350
351	dma->count = count;
352
353	val = msm_read(port, UARTDM_DMEN);
354	val |= dma->enable_bit;
355
356	if (msm_port->is_uartdm < UARTDM_1P4)
357		msm_write(port, val, UARTDM_DMEN);
358
359	msm_reset_dm_count(port, count);
360
361	if (msm_port->is_uartdm > UARTDM_1P3)
362		msm_write(port, val, UARTDM_DMEN);
363
364	dma_async_issue_pending(dma->chan);
365	return 0;
366unmap:
367	dma_unmap_single(port->dev, dma->phys, count, dma->dir);
368	return ret;
369}
370
371static void msm_complete_rx_dma(void *args)
372{
373	struct msm_port *msm_port = args;
374	struct uart_port *port = &msm_port->uart;
375	struct tty_port *tport = &port->state->port;
376	struct msm_dma *dma = &msm_port->rx_dma;
377	int count = 0, i, sysrq;
378	unsigned long flags;
379	u32 val;
380
381	spin_lock_irqsave(&port->lock, flags);
382
383	/* Already stopped */
384	if (!dma->count)
385		goto done;
386
387	val = msm_read(port, UARTDM_DMEN);
388	val &= ~dma->enable_bit;
389	msm_write(port, val, UARTDM_DMEN);
390
391	/* Restore interrupts */
392	msm_port->imr |= UART_IMR_RXLEV | UART_IMR_RXSTALE;
393	msm_write(port, msm_port->imr, UART_IMR);
394
395	if (msm_read(port, UART_SR) & UART_SR_OVERRUN) {
396		port->icount.overrun++;
397		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
398		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
399	}
400
401	count = msm_read(port, UARTDM_RX_TOTAL_SNAP);
402
403	port->icount.rx += count;
404
405	dma->count = 0;
406
407	dma_unmap_single(port->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
408
409	for (i = 0; i < count; i++) {
410		char flag = TTY_NORMAL;
411
412		if (msm_port->break_detected && dma->virt[i] == 0) {
413			port->icount.brk++;
414			flag = TTY_BREAK;
415			msm_port->break_detected = false;
416			if (uart_handle_break(port))
417				continue;
418		}
419
420		if (!(port->read_status_mask & UART_SR_RX_BREAK))
421			flag = TTY_NORMAL;
422
423		spin_unlock_irqrestore(&port->lock, flags);
424		sysrq = uart_handle_sysrq_char(port, dma->virt[i]);
425		spin_lock_irqsave(&port->lock, flags);
426		if (!sysrq)
427			tty_insert_flip_char(tport, dma->virt[i], flag);
428	}
429
430	msm_start_rx_dma(msm_port);
431done:
432	spin_unlock_irqrestore(&port->lock, flags);
433
434	if (count)
435		tty_flip_buffer_push(tport);
436}
437
438static void msm_start_rx_dma(struct msm_port *msm_port)
439{
440	struct msm_dma *dma = &msm_port->rx_dma;
441	struct uart_port *uart = &msm_port->uart;
442	u32 val;
443	int ret;
444
445	if (!dma->chan)
446		return;
447
448	dma->phys = dma_map_single(uart->dev, dma->virt,
449				   UARTDM_RX_SIZE, dma->dir);
450	ret = dma_mapping_error(uart->dev, dma->phys);
451	if (ret)
452		return;
453
454	dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
455						UARTDM_RX_SIZE, DMA_DEV_TO_MEM,
456						DMA_PREP_INTERRUPT);
457	if (!dma->desc)
458		goto unmap;
459
460	dma->desc->callback = msm_complete_rx_dma;
461	dma->desc->callback_param = msm_port;
462
463	dma->cookie = dmaengine_submit(dma->desc);
464	ret = dma_submit_error(dma->cookie);
465	if (ret)
466		goto unmap;
467	/*
468	 * Using DMA for FIFO off-load, no need for "Rx FIFO over
469	 * watermark" or "stale" interrupts, disable them
470	 */
471	msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
472
473	/*
474	 * Well, when DMA is ADM3 engine(implied by <= UARTDM v1.3),
475	 * we need RXSTALE to flush input DMA fifo to memory
476	 */
477	if (msm_port->is_uartdm < UARTDM_1P4)
478		msm_port->imr |= UART_IMR_RXSTALE;
479
480	msm_write(uart, msm_port->imr, UART_IMR);
481
482	dma->count = UARTDM_RX_SIZE;
483
484	dma_async_issue_pending(dma->chan);
485
486	msm_write(uart, UART_CR_CMD_RESET_STALE_INT, UART_CR);
487	msm_write(uart, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
488
489	val = msm_read(uart, UARTDM_DMEN);
490	val |= dma->enable_bit;
491
492	if (msm_port->is_uartdm < UARTDM_1P4)
493		msm_write(uart, val, UARTDM_DMEN);
494
495	msm_write(uart, UARTDM_RX_SIZE, UARTDM_DMRX);
496
497	if (msm_port->is_uartdm > UARTDM_1P3)
498		msm_write(uart, val, UARTDM_DMEN);
499
500	return;
501unmap:
502	dma_unmap_single(uart->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
503}
504
505static void msm_stop_rx(struct uart_port *port)
506{
507	struct msm_port *msm_port = UART_TO_MSM(port);
508	struct msm_dma *dma = &msm_port->rx_dma;
509
510	msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
511	msm_write(port, msm_port->imr, UART_IMR);
512
513	if (dma->chan)
514		msm_stop_dma(port, dma);
515}
516
517static void msm_enable_ms(struct uart_port *port)
518{
519	struct msm_port *msm_port = UART_TO_MSM(port);
520
521	msm_port->imr |= UART_IMR_DELTA_CTS;
522	msm_write(port, msm_port->imr, UART_IMR);
523}
524
525static void msm_handle_rx_dm(struct uart_port *port, unsigned int misr)
526{
527	struct tty_port *tport = &port->state->port;
528	unsigned int sr;
529	int count = 0;
530	struct msm_port *msm_port = UART_TO_MSM(port);
531
532	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
533		port->icount.overrun++;
534		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
535		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
536	}
537
538	if (misr & UART_IMR_RXSTALE) {
539		count = msm_read(port, UARTDM_RX_TOTAL_SNAP) -
540			msm_port->old_snap_state;
541		msm_port->old_snap_state = 0;
542	} else {
543		count = 4 * (msm_read(port, UART_RFWR));
544		msm_port->old_snap_state += count;
545	}
546
547	/* TODO: Precise error reporting */
548
549	port->icount.rx += count;
550
551	while (count > 0) {
552		unsigned char buf[4];
553		int sysrq, r_count, i;
554
555		sr = msm_read(port, UART_SR);
556		if ((sr & UART_SR_RX_READY) == 0) {
557			msm_port->old_snap_state -= count;
558			break;
559		}
560
561		ioread32_rep(port->membase + UARTDM_RF, buf, 1);
562		r_count = min_t(int, count, sizeof(buf));
563
564		for (i = 0; i < r_count; i++) {
565			char flag = TTY_NORMAL;
566
567			if (msm_port->break_detected && buf[i] == 0) {
568				port->icount.brk++;
569				flag = TTY_BREAK;
570				msm_port->break_detected = false;
571				if (uart_handle_break(port))
572					continue;
573			}
574
575			if (!(port->read_status_mask & UART_SR_RX_BREAK))
576				flag = TTY_NORMAL;
577
578			spin_unlock(&port->lock);
579			sysrq = uart_handle_sysrq_char(port, buf[i]);
580			spin_lock(&port->lock);
581			if (!sysrq)
582				tty_insert_flip_char(tport, buf[i], flag);
583		}
584		count -= r_count;
585	}
586
587	spin_unlock(&port->lock);
588	tty_flip_buffer_push(tport);
589	spin_lock(&port->lock);
590
591	if (misr & (UART_IMR_RXSTALE))
592		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
593	msm_write(port, 0xFFFFFF, UARTDM_DMRX);
594	msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
595
596	/* Try to use DMA */
597	msm_start_rx_dma(msm_port);
598}
599
600static void msm_handle_rx(struct uart_port *port)
601{
602	struct tty_port *tport = &port->state->port;
603	unsigned int sr;
604
605	/*
606	 * Handle overrun. My understanding of the hardware is that overrun
607	 * is not tied to the RX buffer, so we handle the case out of band.
608	 */
609	if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
610		port->icount.overrun++;
611		tty_insert_flip_char(tport, 0, TTY_OVERRUN);
612		msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
613	}
614
615	/* and now the main RX loop */
616	while ((sr = msm_read(port, UART_SR)) & UART_SR_RX_READY) {
617		unsigned int c;
618		char flag = TTY_NORMAL;
619		int sysrq;
620
621		c = msm_read(port, UART_RF);
622
623		if (sr & UART_SR_RX_BREAK) {
624			port->icount.brk++;
625			if (uart_handle_break(port))
626				continue;
627		} else if (sr & UART_SR_PAR_FRAME_ERR) {
628			port->icount.frame++;
629		} else {
630			port->icount.rx++;
631		}
632
633		/* Mask conditions we're ignorning. */
634		sr &= port->read_status_mask;
635
636		if (sr & UART_SR_RX_BREAK)
637			flag = TTY_BREAK;
638		else if (sr & UART_SR_PAR_FRAME_ERR)
639			flag = TTY_FRAME;
640
641		spin_unlock(&port->lock);
642		sysrq = uart_handle_sysrq_char(port, c);
643		spin_lock(&port->lock);
644		if (!sysrq)
645			tty_insert_flip_char(tport, c, flag);
646	}
647
648	spin_unlock(&port->lock);
649	tty_flip_buffer_push(tport);
650	spin_lock(&port->lock);
651}
652
653static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
654{
655	struct circ_buf *xmit = &port->state->xmit;
656	struct msm_port *msm_port = UART_TO_MSM(port);
657	unsigned int num_chars;
658	unsigned int tf_pointer = 0;
659	void __iomem *tf;
660
661	if (msm_port->is_uartdm)
662		tf = port->membase + UARTDM_TF;
663	else
664		tf = port->membase + UART_TF;
665
666	if (tx_count && msm_port->is_uartdm)
667		msm_reset_dm_count(port, tx_count);
668
669	while (tf_pointer < tx_count) {
670		int i;
671		char buf[4] = { 0 };
672
673		if (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
674			break;
675
676		if (msm_port->is_uartdm)
677			num_chars = min(tx_count - tf_pointer,
678					(unsigned int)sizeof(buf));
679		else
680			num_chars = 1;
681
682		for (i = 0; i < num_chars; i++) {
683			buf[i] = xmit->buf[xmit->tail + i];
684			port->icount.tx++;
685		}
686
687		iowrite32_rep(tf, buf, 1);
688		xmit->tail = (xmit->tail + num_chars) & (UART_XMIT_SIZE - 1);
689		tf_pointer += num_chars;
690	}
691
692	/* disable tx interrupts if nothing more to send */
693	if (uart_circ_empty(xmit))
694		msm_stop_tx(port);
695
696	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
697		uart_write_wakeup(port);
698}
699
700static void msm_handle_tx(struct uart_port *port)
701{
702	struct msm_port *msm_port = UART_TO_MSM(port);
703	struct circ_buf *xmit = &msm_port->uart.state->xmit;
704	struct msm_dma *dma = &msm_port->tx_dma;
705	unsigned int pio_count, dma_count, dma_min;
706	void __iomem *tf;
707	int err = 0;
708
709	if (port->x_char) {
710		if (msm_port->is_uartdm)
711			tf = port->membase + UARTDM_TF;
712		else
713			tf = port->membase + UART_TF;
714
715		if (msm_port->is_uartdm)
716			msm_reset_dm_count(port, 1);
717
718		iowrite8_rep(tf, &port->x_char, 1);
719		port->icount.tx++;
720		port->x_char = 0;
721		return;
722	}
723
724	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
725		msm_stop_tx(port);
726		return;
727	}
728
729	pio_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
730	dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
731
732	dma_min = 1;	/* Always DMA */
733	if (msm_port->is_uartdm > UARTDM_1P3) {
734		dma_count = UARTDM_TX_AIGN(dma_count);
735		dma_min = UARTDM_BURST_SIZE;
736	} else {
737		if (dma_count > UARTDM_TX_MAX)
738			dma_count = UARTDM_TX_MAX;
739	}
740
741	if (pio_count > port->fifosize)
742		pio_count = port->fifosize;
743
744	if (!dma->chan || dma_count < dma_min)
745		msm_handle_tx_pio(port, pio_count);
746	else
747		err = msm_handle_tx_dma(msm_port, dma_count);
748
749	if (err)	/* fall back to PIO mode */
750		msm_handle_tx_pio(port, pio_count);
751}
752
753static void msm_handle_delta_cts(struct uart_port *port)
754{
755	msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
756	port->icount.cts++;
757	wake_up_interruptible(&port->state->port.delta_msr_wait);
758}
759
760static irqreturn_t msm_uart_irq(int irq, void *dev_id)
761{
762	struct uart_port *port = dev_id;
763	struct msm_port *msm_port = UART_TO_MSM(port);
764	struct msm_dma *dma = &msm_port->rx_dma;
765	unsigned long flags;
766	unsigned int misr;
767	u32 val;
768
769	spin_lock_irqsave(&port->lock, flags);
770	misr = msm_read(port, UART_MISR);
771	msm_write(port, 0, UART_IMR); /* disable interrupt */
772
773	if (misr & UART_IMR_RXBREAK_START) {
774		msm_port->break_detected = true;
775		msm_write(port, UART_CR_CMD_RESET_RXBREAK_START, UART_CR);
776	}
777
778	if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE)) {
779		if (dma->count) {
780			val = UART_CR_CMD_STALE_EVENT_DISABLE;
781			msm_write(port, val, UART_CR);
782			val = UART_CR_CMD_RESET_STALE_INT;
783			msm_write(port, val, UART_CR);
784			/*
785			 * Flush DMA input fifo to memory, this will also
786			 * trigger DMA RX completion
787			 */
788			dmaengine_terminate_all(dma->chan);
789		} else if (msm_port->is_uartdm) {
790			msm_handle_rx_dm(port, misr);
791		} else {
792			msm_handle_rx(port);
793		}
794	}
795	if (misr & UART_IMR_TXLEV)
796		msm_handle_tx(port);
797	if (misr & UART_IMR_DELTA_CTS)
798		msm_handle_delta_cts(port);
799
800	msm_write(port, msm_port->imr, UART_IMR); /* restore interrupt */
801	spin_unlock_irqrestore(&port->lock, flags);
802
803	return IRQ_HANDLED;
804}
805
806static unsigned int msm_tx_empty(struct uart_port *port)
807{
808	return (msm_read(port, UART_SR) & UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
809}
810
811static unsigned int msm_get_mctrl(struct uart_port *port)
812{
813	return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
814}
815
816static void msm_reset(struct uart_port *port)
817{
818	struct msm_port *msm_port = UART_TO_MSM(port);
819
820	/* reset everything */
821	msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
822	msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
823	msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
824	msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR);
825	msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
826	msm_write(port, UART_CR_CMD_SET_RFR, UART_CR);
827
828	/* Disable DM modes */
829	if (msm_port->is_uartdm)
830		msm_write(port, 0, UARTDM_DMEN);
831}
832
833static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
834{
835	unsigned int mr;
836
837	mr = msm_read(port, UART_MR1);
838
839	if (!(mctrl & TIOCM_RTS)) {
840		mr &= ~UART_MR1_RX_RDY_CTL;
841		msm_write(port, mr, UART_MR1);
842		msm_write(port, UART_CR_CMD_RESET_RFR, UART_CR);
843	} else {
844		mr |= UART_MR1_RX_RDY_CTL;
845		msm_write(port, mr, UART_MR1);
846	}
847}
848
849static void msm_break_ctl(struct uart_port *port, int break_ctl)
850{
851	if (break_ctl)
852		msm_write(port, UART_CR_CMD_START_BREAK, UART_CR);
853	else
854		msm_write(port, UART_CR_CMD_STOP_BREAK, UART_CR);
855}
856
857struct msm_baud_map {
858	u16	divisor;
859	u8	code;
860	u8	rxstale;
861};
862
863static const struct msm_baud_map *
864msm_find_best_baud(struct uart_port *port, unsigned int baud)
865{
866	unsigned int i, divisor;
867	const struct msm_baud_map *entry;
868	static const struct msm_baud_map table[] = {
869		{ 1536, 0x00,  1 },
870		{  768, 0x11,  1 },
871		{  384, 0x22,  1 },
872		{  192, 0x33,  1 },
873		{   96, 0x44,  1 },
874		{   48, 0x55,  1 },
875		{   32, 0x66,  1 },
876		{   24, 0x77,  1 },
877		{   16, 0x88,  1 },
878		{   12, 0x99,  6 },
879		{    8, 0xaa,  6 },
880		{    6, 0xbb,  6 },
881		{    4, 0xcc,  6 },
882		{    3, 0xdd,  8 },
883		{    2, 0xee, 16 },
884		{    1, 0xff, 31 },
885		{    0, 0xff, 31 },
886	};
887
888	divisor = uart_get_divisor(port, baud);
889
890	for (i = 0, entry = table; i < ARRAY_SIZE(table); i++, entry++)
891		if (entry->divisor <= divisor)
892			break;
893
894	return entry; /* Default to smallest divider */
895}
896
897static int msm_set_baud_rate(struct uart_port *port, unsigned int baud,
898			     unsigned long *saved_flags)
899{
900	unsigned int rxstale, watermark, mask;
901	struct msm_port *msm_port = UART_TO_MSM(port);
902	const struct msm_baud_map *entry;
903	unsigned long flags;
904
905	entry = msm_find_best_baud(port, baud);
906
907	msm_write(port, entry->code, UART_CSR);
908
909	if (baud > 460800)
910		port->uartclk = baud * 16;
911
912	flags = *saved_flags;
913	spin_unlock_irqrestore(&port->lock, flags);
914
915	clk_set_rate(msm_port->clk, port->uartclk);
916
917	spin_lock_irqsave(&port->lock, flags);
918	*saved_flags = flags;
919
920	/* RX stale watermark */
921	rxstale = entry->rxstale;
922	watermark = UART_IPR_STALE_LSB & rxstale;
923	if (msm_port->is_uartdm) {
924		mask = UART_DM_IPR_STALE_TIMEOUT_MSB;
925	} else {
926		watermark |= UART_IPR_RXSTALE_LAST;
927		mask = UART_IPR_STALE_TIMEOUT_MSB;
928	}
929
930	watermark |= mask & (rxstale << 2);
931
932	msm_write(port, watermark, UART_IPR);
933
934	/* set RX watermark */
935	watermark = (port->fifosize * 3) / 4;
936	msm_write(port, watermark, UART_RFWR);
937
938	/* set TX watermark */
939	msm_write(port, 10, UART_TFWR);
940
941	msm_write(port, UART_CR_CMD_PROTECTION_EN, UART_CR);
942	msm_reset(port);
943
944	/* Enable RX and TX */
945	msm_write(port, UART_CR_TX_ENABLE | UART_CR_RX_ENABLE, UART_CR);
946
947	/* turn on RX and CTS interrupts */
948	msm_port->imr = UART_IMR_RXLEV | UART_IMR_RXSTALE |
949			UART_IMR_CURRENT_CTS | UART_IMR_RXBREAK_START;
950
951	msm_write(port, msm_port->imr, UART_IMR);
952
953	if (msm_port->is_uartdm) {
954		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
955		msm_write(port, 0xFFFFFF, UARTDM_DMRX);
956		msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE, UART_CR);
957	}
958
959	return baud;
960}
961
962static void msm_init_clock(struct uart_port *port)
963{
964	struct msm_port *msm_port = UART_TO_MSM(port);
965
966	clk_prepare_enable(msm_port->clk);
967	clk_prepare_enable(msm_port->pclk);
968	msm_serial_set_mnd_regs(port);
969}
970
971static int msm_startup(struct uart_port *port)
972{
973	struct msm_port *msm_port = UART_TO_MSM(port);
974	unsigned int data, rfr_level, mask;
975	int ret;
976
977	snprintf(msm_port->name, sizeof(msm_port->name),
978		 "msm_serial%d", port->line);
979
980	ret = request_irq(port->irq, msm_uart_irq, IRQF_TRIGGER_HIGH,
981			  msm_port->name, port);
982	if (unlikely(ret))
983		return ret;
984
985	msm_init_clock(port);
986
987	if (likely(port->fifosize > 12))
988		rfr_level = port->fifosize - 12;
989	else
990		rfr_level = port->fifosize;
991
992	/* set automatic RFR level */
993	data = msm_read(port, UART_MR1);
994
995	if (msm_port->is_uartdm)
996		mask = UART_DM_MR1_AUTO_RFR_LEVEL1;
997	else
998		mask = UART_MR1_AUTO_RFR_LEVEL1;
999
1000	data &= ~mask;
1001	data &= ~UART_MR1_AUTO_RFR_LEVEL0;
1002	data |= mask & (rfr_level << 2);
1003	data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
1004	msm_write(port, data, UART_MR1);
1005
1006	if (msm_port->is_uartdm) {
1007		msm_request_tx_dma(msm_port, msm_port->uart.mapbase);
1008		msm_request_rx_dma(msm_port, msm_port->uart.mapbase);
1009	}
1010
1011	return 0;
1012}
1013
1014static void msm_shutdown(struct uart_port *port)
1015{
1016	struct msm_port *msm_port = UART_TO_MSM(port);
1017
1018	msm_port->imr = 0;
1019	msm_write(port, 0, UART_IMR); /* disable interrupts */
1020
1021	if (msm_port->is_uartdm)
1022		msm_release_dma(msm_port);
1023
1024	clk_disable_unprepare(msm_port->clk);
1025
1026	free_irq(port->irq, port);
1027}
1028
1029static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
1030			    struct ktermios *old)
1031{
1032	struct msm_port *msm_port = UART_TO_MSM(port);
1033	struct msm_dma *dma = &msm_port->rx_dma;
1034	unsigned long flags;
1035	unsigned int baud, mr;
1036
1037	spin_lock_irqsave(&port->lock, flags);
1038
1039	if (dma->chan) /* Terminate if any */
1040		msm_stop_dma(port, dma);
1041
1042	/* calculate and set baud rate */
1043	baud = uart_get_baud_rate(port, termios, old, 300, 4000000);
1044	baud = msm_set_baud_rate(port, baud, &flags);
1045	if (tty_termios_baud_rate(termios))
1046		tty_termios_encode_baud_rate(termios, baud, baud);
1047
1048	/* calculate parity */
1049	mr = msm_read(port, UART_MR2);
1050	mr &= ~UART_MR2_PARITY_MODE;
1051	if (termios->c_cflag & PARENB) {
1052		if (termios->c_cflag & PARODD)
1053			mr |= UART_MR2_PARITY_MODE_ODD;
1054		else if (termios->c_cflag & CMSPAR)
1055			mr |= UART_MR2_PARITY_MODE_SPACE;
1056		else
1057			mr |= UART_MR2_PARITY_MODE_EVEN;
1058	}
1059
1060	/* calculate bits per char */
1061	mr &= ~UART_MR2_BITS_PER_CHAR;
1062	switch (termios->c_cflag & CSIZE) {
1063	case CS5:
1064		mr |= UART_MR2_BITS_PER_CHAR_5;
1065		break;
1066	case CS6:
1067		mr |= UART_MR2_BITS_PER_CHAR_6;
1068		break;
1069	case CS7:
1070		mr |= UART_MR2_BITS_PER_CHAR_7;
1071		break;
1072	case CS8:
1073	default:
1074		mr |= UART_MR2_BITS_PER_CHAR_8;
1075		break;
1076	}
1077
1078	/* calculate stop bits */
1079	mr &= ~(UART_MR2_STOP_BIT_LEN_ONE | UART_MR2_STOP_BIT_LEN_TWO);
1080	if (termios->c_cflag & CSTOPB)
1081		mr |= UART_MR2_STOP_BIT_LEN_TWO;
1082	else
1083		mr |= UART_MR2_STOP_BIT_LEN_ONE;
1084
1085	/* set parity, bits per char, and stop bit */
1086	msm_write(port, mr, UART_MR2);
1087
1088	/* calculate and set hardware flow control */
1089	mr = msm_read(port, UART_MR1);
1090	mr &= ~(UART_MR1_CTS_CTL | UART_MR1_RX_RDY_CTL);
1091	if (termios->c_cflag & CRTSCTS) {
1092		mr |= UART_MR1_CTS_CTL;
1093		mr |= UART_MR1_RX_RDY_CTL;
1094	}
1095	msm_write(port, mr, UART_MR1);
1096
1097	/* Configure status bits to ignore based on termio flags. */
1098	port->read_status_mask = 0;
1099	if (termios->c_iflag & INPCK)
1100		port->read_status_mask |= UART_SR_PAR_FRAME_ERR;
1101	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1102		port->read_status_mask |= UART_SR_RX_BREAK;
1103
1104	uart_update_timeout(port, termios->c_cflag, baud);
1105
1106	/* Try to use DMA */
1107	msm_start_rx_dma(msm_port);
1108
1109	spin_unlock_irqrestore(&port->lock, flags);
1110}
1111
1112static const char *msm_type(struct uart_port *port)
1113{
1114	return "MSM";
1115}
1116
1117static void msm_release_port(struct uart_port *port)
1118{
1119	struct platform_device *pdev = to_platform_device(port->dev);
1120	struct resource *uart_resource;
1121	resource_size_t size;
1122
1123	uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1124	if (unlikely(!uart_resource))
1125		return;
1126	size = resource_size(uart_resource);
1127
1128	release_mem_region(port->mapbase, size);
1129	iounmap(port->membase);
1130	port->membase = NULL;
1131}
1132
1133static int msm_request_port(struct uart_port *port)
1134{
1135	struct platform_device *pdev = to_platform_device(port->dev);
1136	struct resource *uart_resource;
1137	resource_size_t size;
1138	int ret;
1139
1140	uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1141	if (unlikely(!uart_resource))
1142		return -ENXIO;
1143
1144	size = resource_size(uart_resource);
1145
1146	if (!request_mem_region(port->mapbase, size, "msm_serial"))
1147		return -EBUSY;
1148
1149	port->membase = ioremap(port->mapbase, size);
1150	if (!port->membase) {
1151		ret = -EBUSY;
1152		goto fail_release_port;
1153	}
1154
1155	return 0;
1156
1157fail_release_port:
1158	release_mem_region(port->mapbase, size);
1159	return ret;
1160}
1161
1162static void msm_config_port(struct uart_port *port, int flags)
1163{
1164	int ret;
1165
1166	if (flags & UART_CONFIG_TYPE) {
1167		port->type = PORT_MSM;
1168		ret = msm_request_port(port);
1169		if (ret)
1170			return;
1171	}
1172}
1173
1174static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
1175{
1176	if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
1177		return -EINVAL;
1178	if (unlikely(port->irq != ser->irq))
1179		return -EINVAL;
1180	return 0;
1181}
1182
1183static void msm_power(struct uart_port *port, unsigned int state,
1184		      unsigned int oldstate)
1185{
1186	struct msm_port *msm_port = UART_TO_MSM(port);
1187
1188	switch (state) {
1189	case 0:
1190		clk_prepare_enable(msm_port->clk);
1191		clk_prepare_enable(msm_port->pclk);
1192		break;
1193	case 3:
1194		clk_disable_unprepare(msm_port->clk);
1195		clk_disable_unprepare(msm_port->pclk);
1196		break;
1197	default:
1198		pr_err("msm_serial: Unknown PM state %d\n", state);
1199	}
1200}
1201
1202#ifdef CONFIG_CONSOLE_POLL
1203static int msm_poll_get_char_single(struct uart_port *port)
1204{
1205	struct msm_port *msm_port = UART_TO_MSM(port);
1206	unsigned int rf_reg = msm_port->is_uartdm ? UARTDM_RF : UART_RF;
1207
1208	if (!(msm_read(port, UART_SR) & UART_SR_RX_READY))
1209		return NO_POLL_CHAR;
1210
1211	return msm_read(port, rf_reg) & 0xff;
1212}
1213
1214static int msm_poll_get_char_dm(struct uart_port *port)
1215{
1216	int c;
1217	static u32 slop;
1218	static int count;
1219	unsigned char *sp = (unsigned char *)&slop;
1220
1221	/* Check if a previous read had more than one char */
1222	if (count) {
1223		c = sp[sizeof(slop) - count];
1224		count--;
1225	/* Or if FIFO is empty */
1226	} else if (!(msm_read(port, UART_SR) & UART_SR_RX_READY)) {
1227		/*
1228		 * If RX packing buffer has less than a word, force stale to
1229		 * push contents into RX FIFO
1230		 */
1231		count = msm_read(port, UARTDM_RXFS);
1232		count = (count >> UARTDM_RXFS_BUF_SHIFT) & UARTDM_RXFS_BUF_MASK;
1233		if (count) {
1234			msm_write(port, UART_CR_CMD_FORCE_STALE, UART_CR);
1235			slop = msm_read(port, UARTDM_RF);
1236			c = sp[0];
1237			count--;
1238			msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
1239			msm_write(port, 0xFFFFFF, UARTDM_DMRX);
1240			msm_write(port, UART_CR_CMD_STALE_EVENT_ENABLE,
1241				  UART_CR);
1242		} else {
1243			c = NO_POLL_CHAR;
1244		}
1245	/* FIFO has a word */
1246	} else {
1247		slop = msm_read(port, UARTDM_RF);
1248		c = sp[0];
1249		count = sizeof(slop) - 1;
1250	}
1251
1252	return c;
1253}
1254
1255static int msm_poll_get_char(struct uart_port *port)
1256{
1257	u32 imr;
1258	int c;
1259	struct msm_port *msm_port = UART_TO_MSM(port);
1260
1261	/* Disable all interrupts */
1262	imr = msm_read(port, UART_IMR);
1263	msm_write(port, 0, UART_IMR);
1264
1265	if (msm_port->is_uartdm)
1266		c = msm_poll_get_char_dm(port);
1267	else
1268		c = msm_poll_get_char_single(port);
1269
1270	/* Enable interrupts */
1271	msm_write(port, imr, UART_IMR);
1272
1273	return c;
1274}
1275
1276static void msm_poll_put_char(struct uart_port *port, unsigned char c)
1277{
1278	u32 imr;
1279	struct msm_port *msm_port = UART_TO_MSM(port);
1280
1281	/* Disable all interrupts */
1282	imr = msm_read(port, UART_IMR);
1283	msm_write(port, 0, UART_IMR);
1284
1285	if (msm_port->is_uartdm)
1286		msm_reset_dm_count(port, 1);
1287
1288	/* Wait until FIFO is empty */
1289	while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
1290		cpu_relax();
1291
1292	/* Write a character */
1293	msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
1294
1295	/* Wait until FIFO is empty */
1296	while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
1297		cpu_relax();
1298
1299	/* Enable interrupts */
1300	msm_write(port, imr, UART_IMR);
1301}
1302#endif
1303
1304static struct uart_ops msm_uart_pops = {
1305	.tx_empty = msm_tx_empty,
1306	.set_mctrl = msm_set_mctrl,
1307	.get_mctrl = msm_get_mctrl,
1308	.stop_tx = msm_stop_tx,
1309	.start_tx = msm_start_tx,
1310	.stop_rx = msm_stop_rx,
1311	.enable_ms = msm_enable_ms,
1312	.break_ctl = msm_break_ctl,
1313	.startup = msm_startup,
1314	.shutdown = msm_shutdown,
1315	.set_termios = msm_set_termios,
1316	.type = msm_type,
1317	.release_port = msm_release_port,
1318	.request_port = msm_request_port,
1319	.config_port = msm_config_port,
1320	.verify_port = msm_verify_port,
1321	.pm = msm_power,
1322#ifdef CONFIG_CONSOLE_POLL
1323	.poll_get_char	= msm_poll_get_char,
1324	.poll_put_char	= msm_poll_put_char,
1325#endif
1326};
1327
1328static struct msm_port msm_uart_ports[] = {
1329	{
1330		.uart = {
1331			.iotype = UPIO_MEM,
1332			.ops = &msm_uart_pops,
1333			.flags = UPF_BOOT_AUTOCONF,
1334			.fifosize = 64,
1335			.line = 0,
1336		},
1337	},
1338	{
1339		.uart = {
1340			.iotype = UPIO_MEM,
1341			.ops = &msm_uart_pops,
1342			.flags = UPF_BOOT_AUTOCONF,
1343			.fifosize = 64,
1344			.line = 1,
1345		},
1346	},
1347	{
1348		.uart = {
1349			.iotype = UPIO_MEM,
1350			.ops = &msm_uart_pops,
1351			.flags = UPF_BOOT_AUTOCONF,
1352			.fifosize = 64,
1353			.line = 2,
1354		},
1355	},
1356};
1357
1358#define UART_NR	ARRAY_SIZE(msm_uart_ports)
1359
1360static inline struct uart_port *msm_get_port_from_line(unsigned int line)
1361{
1362	return &msm_uart_ports[line].uart;
1363}
1364
1365#ifdef CONFIG_SERIAL_MSM_CONSOLE
1366static void __msm_console_write(struct uart_port *port, const char *s,
1367				unsigned int count, bool is_uartdm)
1368{
1369	int i;
1370	int num_newlines = 0;
1371	bool replaced = false;
1372	void __iomem *tf;
1373
1374	if (is_uartdm)
1375		tf = port->membase + UARTDM_TF;
1376	else
1377		tf = port->membase + UART_TF;
1378
1379	/* Account for newlines that will get a carriage return added */
1380	for (i = 0; i < count; i++)
1381		if (s[i] == '\n')
1382			num_newlines++;
1383	count += num_newlines;
1384
1385	spin_lock(&port->lock);
1386	if (is_uartdm)
1387		msm_reset_dm_count(port, count);
1388
1389	i = 0;
1390	while (i < count) {
1391		int j;
1392		unsigned int num_chars;
1393		char buf[4] = { 0 };
1394
1395		if (is_uartdm)
1396			num_chars = min(count - i, (unsigned int)sizeof(buf));
1397		else
1398			num_chars = 1;
1399
1400		for (j = 0; j < num_chars; j++) {
1401			char c = *s;
1402
1403			if (c == '\n' && !replaced) {
1404				buf[j] = '\r';
1405				j++;
1406				replaced = true;
1407			}
1408			if (j < num_chars) {
1409				buf[j] = c;
1410				s++;
1411				replaced = false;
1412			}
1413		}
1414
1415		while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
1416			cpu_relax();
1417
1418		iowrite32_rep(tf, buf, 1);
1419		i += num_chars;
1420	}
1421	spin_unlock(&port->lock);
1422}
1423
1424static void msm_console_write(struct console *co, const char *s,
1425			      unsigned int count)
1426{
1427	struct uart_port *port;
1428	struct msm_port *msm_port;
1429
1430	BUG_ON(co->index < 0 || co->index >= UART_NR);
1431
1432	port = msm_get_port_from_line(co->index);
1433	msm_port = UART_TO_MSM(port);
1434
1435	__msm_console_write(port, s, count, msm_port->is_uartdm);
1436}
1437
1438static int __init msm_console_setup(struct console *co, char *options)
1439{
1440	struct uart_port *port;
1441	int baud = 115200;
1442	int bits = 8;
1443	int parity = 'n';
1444	int flow = 'n';
1445
1446	if (unlikely(co->index >= UART_NR || co->index < 0))
1447		return -ENXIO;
1448
1449	port = msm_get_port_from_line(co->index);
1450
1451	if (unlikely(!port->membase))
1452		return -ENXIO;
1453
1454	msm_init_clock(port);
1455
1456	if (options)
1457		uart_parse_options(options, &baud, &parity, &bits, &flow);
1458
1459	pr_info("msm_serial: console setup on port #%d\n", port->line);
1460
1461	return uart_set_options(port, co, baud, parity, bits, flow);
1462}
1463
1464static void
1465msm_serial_early_write(struct console *con, const char *s, unsigned n)
1466{
1467	struct earlycon_device *dev = con->data;
1468
1469	__msm_console_write(&dev->port, s, n, false);
1470}
1471
1472static int __init
1473msm_serial_early_console_setup(struct earlycon_device *device, const char *opt)
1474{
1475	if (!device->port.membase)
1476		return -ENODEV;
1477
1478	device->con->write = msm_serial_early_write;
1479	return 0;
1480}
1481EARLYCON_DECLARE(msm_serial, msm_serial_early_console_setup);
1482OF_EARLYCON_DECLARE(msm_serial, "qcom,msm-uart",
1483		    msm_serial_early_console_setup);
1484
1485static void
1486msm_serial_early_write_dm(struct console *con, const char *s, unsigned n)
1487{
1488	struct earlycon_device *dev = con->data;
1489
1490	__msm_console_write(&dev->port, s, n, true);
1491}
1492
1493static int __init
1494msm_serial_early_console_setup_dm(struct earlycon_device *device,
1495				  const char *opt)
1496{
1497	if (!device->port.membase)
1498		return -ENODEV;
1499
1500	device->con->write = msm_serial_early_write_dm;
1501	return 0;
1502}
1503EARLYCON_DECLARE(msm_serial_dm, msm_serial_early_console_setup_dm);
1504OF_EARLYCON_DECLARE(msm_serial_dm, "qcom,msm-uartdm",
1505		    msm_serial_early_console_setup_dm);
1506
1507static struct uart_driver msm_uart_driver;
1508
1509static struct console msm_console = {
1510	.name = "ttyMSM",
1511	.write = msm_console_write,
1512	.device = uart_console_device,
1513	.setup = msm_console_setup,
1514	.flags = CON_PRINTBUFFER,
1515	.index = -1,
1516	.data = &msm_uart_driver,
1517};
1518
1519#define MSM_CONSOLE	(&msm_console)
1520
1521#else
1522#define MSM_CONSOLE	NULL
1523#endif
1524
1525static struct uart_driver msm_uart_driver = {
1526	.owner = THIS_MODULE,
1527	.driver_name = "msm_serial",
1528	.dev_name = "ttyMSM",
1529	.nr = UART_NR,
1530	.cons = MSM_CONSOLE,
1531};
1532
1533static atomic_t msm_uart_next_id = ATOMIC_INIT(0);
1534
1535static const struct of_device_id msm_uartdm_table[] = {
1536	{ .compatible = "qcom,msm-uartdm-v1.1", .data = (void *)UARTDM_1P1 },
1537	{ .compatible = "qcom,msm-uartdm-v1.2", .data = (void *)UARTDM_1P2 },
1538	{ .compatible = "qcom,msm-uartdm-v1.3", .data = (void *)UARTDM_1P3 },
1539	{ .compatible = "qcom,msm-uartdm-v1.4", .data = (void *)UARTDM_1P4 },
1540	{ }
1541};
1542
1543static int msm_serial_probe(struct platform_device *pdev)
1544{
1545	struct msm_port *msm_port;
1546	struct resource *resource;
1547	struct uart_port *port;
1548	const struct of_device_id *id;
1549	int irq, line;
1550
1551	if (pdev->dev.of_node)
1552		line = of_alias_get_id(pdev->dev.of_node, "serial");
1553	else
1554		line = pdev->id;
1555
1556	if (line < 0)
1557		line = atomic_inc_return(&msm_uart_next_id) - 1;
1558
1559	if (unlikely(line < 0 || line >= UART_NR))
1560		return -ENXIO;
1561
1562	dev_info(&pdev->dev, "msm_serial: detected port #%d\n", line);
1563
1564	port = msm_get_port_from_line(line);
1565	port->dev = &pdev->dev;
1566	msm_port = UART_TO_MSM(port);
1567
1568	id = of_match_device(msm_uartdm_table, &pdev->dev);
1569	if (id)
1570		msm_port->is_uartdm = (unsigned long)id->data;
1571	else
1572		msm_port->is_uartdm = 0;
1573
1574	msm_port->clk = devm_clk_get(&pdev->dev, "core");
1575	if (IS_ERR(msm_port->clk))
1576		return PTR_ERR(msm_port->clk);
1577
1578	if (msm_port->is_uartdm) {
1579		msm_port->pclk = devm_clk_get(&pdev->dev, "iface");
1580		if (IS_ERR(msm_port->pclk))
1581			return PTR_ERR(msm_port->pclk);
1582
1583		clk_set_rate(msm_port->clk, 1843200);
1584	}
1585
1586	port->uartclk = clk_get_rate(msm_port->clk);
1587	dev_info(&pdev->dev, "uartclk = %d\n", port->uartclk);
1588
1589	resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1590	if (unlikely(!resource))
1591		return -ENXIO;
1592	port->mapbase = resource->start;
1593
1594	irq = platform_get_irq(pdev, 0);
1595	if (unlikely(irq < 0))
1596		return -ENXIO;
1597	port->irq = irq;
1598
1599	platform_set_drvdata(pdev, port);
1600
1601	return uart_add_one_port(&msm_uart_driver, port);
1602}
1603
1604static int msm_serial_remove(struct platform_device *pdev)
1605{
1606	struct uart_port *port = platform_get_drvdata(pdev);
1607
1608	uart_remove_one_port(&msm_uart_driver, port);
1609
1610	return 0;
1611}
1612
1613static const struct of_device_id msm_match_table[] = {
1614	{ .compatible = "qcom,msm-uart" },
1615	{ .compatible = "qcom,msm-uartdm" },
1616	{}
1617};
1618
1619static struct platform_driver msm_platform_driver = {
1620	.remove = msm_serial_remove,
1621	.probe = msm_serial_probe,
1622	.driver = {
1623		.name = "msm_serial",
1624		.of_match_table = msm_match_table,
1625	},
1626};
1627
1628static int __init msm_serial_init(void)
1629{
1630	int ret;
1631
1632	ret = uart_register_driver(&msm_uart_driver);
1633	if (unlikely(ret))
1634		return ret;
1635
1636	ret = platform_driver_register(&msm_platform_driver);
1637	if (unlikely(ret))
1638		uart_unregister_driver(&msm_uart_driver);
1639
1640	pr_info("msm_serial: driver initialized\n");
1641
1642	return ret;
1643}
1644
1645static void __exit msm_serial_exit(void)
1646{
1647	platform_driver_unregister(&msm_platform_driver);
1648	uart_unregister_driver(&msm_uart_driver);
1649}
1650
1651module_init(msm_serial_init);
1652module_exit(msm_serial_exit);
1653
1654MODULE_AUTHOR("Robert Love <rlove@google.com>");
1655MODULE_DESCRIPTION("Driver for msm7x serial device");
1656MODULE_LICENSE("GPL");
1657