xref: /openbmc/linux/drivers/mmc/host/jz4740_mmc.c (revision 0c7beb2d)
1 /*
2  *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
3  *  Copyright (C) 2013, Imagination Technologies
4  *
5  *  JZ4740 SD/MMC controller driver
6  *
7  *  This program is free software; you can redistribute  it and/or modify it
8  *  under  the terms of  the GNU General  Public License as published by the
9  *  Free Software Foundation;  either version 2 of the  License, or (at your
10  *  option) any later version.
11  *
12  *  You should have received a copy of the  GNU General Public License along
13  *  with this program; if not, write  to the Free Software Foundation, Inc.,
14  *  675 Mass Ave, Cambridge, MA 02139, USA.
15  *
16  */
17 
18 #include <linux/bitops.h>
19 #include <linux/clk.h>
20 #include <linux/delay.h>
21 #include <linux/dmaengine.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/err.h>
24 #include <linux/interrupt.h>
25 #include <linux/io.h>
26 #include <linux/irq.h>
27 #include <linux/mmc/host.h>
28 #include <linux/mmc/slot-gpio.h>
29 #include <linux/module.h>
30 #include <linux/of_device.h>
31 #include <linux/pinctrl/consumer.h>
32 #include <linux/platform_device.h>
33 #include <linux/scatterlist.h>
34 
35 #include <asm/cacheflush.h>
36 
37 #include <asm/mach-jz4740/dma.h>
38 
39 #define JZ_REG_MMC_STRPCL	0x00
40 #define JZ_REG_MMC_STATUS	0x04
41 #define JZ_REG_MMC_CLKRT	0x08
42 #define JZ_REG_MMC_CMDAT	0x0C
43 #define JZ_REG_MMC_RESTO	0x10
44 #define JZ_REG_MMC_RDTO		0x14
45 #define JZ_REG_MMC_BLKLEN	0x18
46 #define JZ_REG_MMC_NOB		0x1C
47 #define JZ_REG_MMC_SNOB		0x20
48 #define JZ_REG_MMC_IMASK	0x24
49 #define JZ_REG_MMC_IREG		0x28
50 #define JZ_REG_MMC_CMD		0x2C
51 #define JZ_REG_MMC_ARG		0x30
52 #define JZ_REG_MMC_RESP_FIFO	0x34
53 #define JZ_REG_MMC_RXFIFO	0x38
54 #define JZ_REG_MMC_TXFIFO	0x3C
55 #define JZ_REG_MMC_DMAC		0x44
56 
57 #define JZ_MMC_STRPCL_EXIT_MULTIPLE BIT(7)
58 #define JZ_MMC_STRPCL_EXIT_TRANSFER BIT(6)
59 #define JZ_MMC_STRPCL_START_READWAIT BIT(5)
60 #define JZ_MMC_STRPCL_STOP_READWAIT BIT(4)
61 #define JZ_MMC_STRPCL_RESET BIT(3)
62 #define JZ_MMC_STRPCL_START_OP BIT(2)
63 #define JZ_MMC_STRPCL_CLOCK_CONTROL (BIT(1) | BIT(0))
64 #define JZ_MMC_STRPCL_CLOCK_STOP BIT(0)
65 #define JZ_MMC_STRPCL_CLOCK_START BIT(1)
66 
67 
68 #define JZ_MMC_STATUS_IS_RESETTING BIT(15)
69 #define JZ_MMC_STATUS_SDIO_INT_ACTIVE BIT(14)
70 #define JZ_MMC_STATUS_PRG_DONE BIT(13)
71 #define JZ_MMC_STATUS_DATA_TRAN_DONE BIT(12)
72 #define JZ_MMC_STATUS_END_CMD_RES BIT(11)
73 #define JZ_MMC_STATUS_DATA_FIFO_AFULL BIT(10)
74 #define JZ_MMC_STATUS_IS_READWAIT BIT(9)
75 #define JZ_MMC_STATUS_CLK_EN BIT(8)
76 #define JZ_MMC_STATUS_DATA_FIFO_FULL BIT(7)
77 #define JZ_MMC_STATUS_DATA_FIFO_EMPTY BIT(6)
78 #define JZ_MMC_STATUS_CRC_RES_ERR BIT(5)
79 #define JZ_MMC_STATUS_CRC_READ_ERROR BIT(4)
80 #define JZ_MMC_STATUS_TIMEOUT_WRITE BIT(3)
81 #define JZ_MMC_STATUS_CRC_WRITE_ERROR BIT(2)
82 #define JZ_MMC_STATUS_TIMEOUT_RES BIT(1)
83 #define JZ_MMC_STATUS_TIMEOUT_READ BIT(0)
84 
85 #define JZ_MMC_STATUS_READ_ERROR_MASK (BIT(4) | BIT(0))
86 #define JZ_MMC_STATUS_WRITE_ERROR_MASK (BIT(3) | BIT(2))
87 
88 
89 #define JZ_MMC_CMDAT_IO_ABORT BIT(11)
90 #define JZ_MMC_CMDAT_BUS_WIDTH_4BIT BIT(10)
91 #define JZ_MMC_CMDAT_DMA_EN BIT(8)
92 #define JZ_MMC_CMDAT_INIT BIT(7)
93 #define JZ_MMC_CMDAT_BUSY BIT(6)
94 #define JZ_MMC_CMDAT_STREAM BIT(5)
95 #define JZ_MMC_CMDAT_WRITE BIT(4)
96 #define JZ_MMC_CMDAT_DATA_EN BIT(3)
97 #define JZ_MMC_CMDAT_RESPONSE_FORMAT (BIT(2) | BIT(1) | BIT(0))
98 #define JZ_MMC_CMDAT_RSP_R1 1
99 #define JZ_MMC_CMDAT_RSP_R2 2
100 #define JZ_MMC_CMDAT_RSP_R3 3
101 
102 #define JZ_MMC_IRQ_SDIO BIT(7)
103 #define JZ_MMC_IRQ_TXFIFO_WR_REQ BIT(6)
104 #define JZ_MMC_IRQ_RXFIFO_RD_REQ BIT(5)
105 #define JZ_MMC_IRQ_END_CMD_RES BIT(2)
106 #define JZ_MMC_IRQ_PRG_DONE BIT(1)
107 #define JZ_MMC_IRQ_DATA_TRAN_DONE BIT(0)
108 
109 #define JZ_MMC_DMAC_DMA_SEL BIT(1)
110 #define JZ_MMC_DMAC_DMA_EN BIT(0)
111 
112 #define JZ_MMC_CLK_RATE 24000000
113 
114 enum jz4740_mmc_version {
115 	JZ_MMC_JZ4740,
116 	JZ_MMC_JZ4725B,
117 	JZ_MMC_JZ4780,
118 };
119 
120 enum jz4740_mmc_state {
121 	JZ4740_MMC_STATE_READ_RESPONSE,
122 	JZ4740_MMC_STATE_TRANSFER_DATA,
123 	JZ4740_MMC_STATE_SEND_STOP,
124 	JZ4740_MMC_STATE_DONE,
125 };
126 
127 /*
128  * The MMC core allows to prepare a mmc_request while another mmc_request
129  * is in-flight. This is used via the pre_req/post_req hooks.
130  * This driver uses the pre_req/post_req hooks to map/unmap the mmc_request.
131  * Following what other drivers do (sdhci, dw_mmc) we use the following cookie
132  * flags to keep track of the mmc_request mapping state.
133  *
134  * COOKIE_UNMAPPED: the request is not mapped.
135  * COOKIE_PREMAPPED: the request was mapped in pre_req,
136  * and should be unmapped in post_req.
137  * COOKIE_MAPPED: the request was mapped in the irq handler,
138  * and should be unmapped before mmc_request_done is called..
139  */
140 enum jz4780_cookie {
141 	COOKIE_UNMAPPED = 0,
142 	COOKIE_PREMAPPED,
143 	COOKIE_MAPPED,
144 };
145 
146 struct jz4740_mmc_host {
147 	struct mmc_host *mmc;
148 	struct platform_device *pdev;
149 	struct clk *clk;
150 
151 	enum jz4740_mmc_version version;
152 
153 	int irq;
154 	int card_detect_irq;
155 
156 	void __iomem *base;
157 	struct resource *mem_res;
158 	struct mmc_request *req;
159 	struct mmc_command *cmd;
160 
161 	unsigned long waiting;
162 
163 	uint32_t cmdat;
164 
165 	uint32_t irq_mask;
166 
167 	spinlock_t lock;
168 
169 	struct timer_list timeout_timer;
170 	struct sg_mapping_iter miter;
171 	enum jz4740_mmc_state state;
172 
173 	/* DMA support */
174 	struct dma_chan *dma_rx;
175 	struct dma_chan *dma_tx;
176 	bool use_dma;
177 
178 /* The DMA trigger level is 8 words, that is to say, the DMA read
179  * trigger is when data words in MSC_RXFIFO is >= 8 and the DMA write
180  * trigger is when data words in MSC_TXFIFO is < 8.
181  */
182 #define JZ4740_MMC_FIFO_HALF_SIZE 8
183 };
184 
185 static void jz4740_mmc_write_irq_mask(struct jz4740_mmc_host *host,
186 				      uint32_t val)
187 {
188 	if (host->version >= JZ_MMC_JZ4725B)
189 		return writel(val, host->base + JZ_REG_MMC_IMASK);
190 	else
191 		return writew(val, host->base + JZ_REG_MMC_IMASK);
192 }
193 
194 static void jz4740_mmc_write_irq_reg(struct jz4740_mmc_host *host,
195 				     uint32_t val)
196 {
197 	if (host->version >= JZ_MMC_JZ4780)
198 		return writel(val, host->base + JZ_REG_MMC_IREG);
199 	else
200 		return writew(val, host->base + JZ_REG_MMC_IREG);
201 }
202 
203 static uint32_t jz4740_mmc_read_irq_reg(struct jz4740_mmc_host *host)
204 {
205 	if (host->version >= JZ_MMC_JZ4780)
206 		return readl(host->base + JZ_REG_MMC_IREG);
207 	else
208 		return readw(host->base + JZ_REG_MMC_IREG);
209 }
210 
211 /*----------------------------------------------------------------------------*/
212 /* DMA infrastructure */
213 
214 static void jz4740_mmc_release_dma_channels(struct jz4740_mmc_host *host)
215 {
216 	if (!host->use_dma)
217 		return;
218 
219 	dma_release_channel(host->dma_tx);
220 	dma_release_channel(host->dma_rx);
221 }
222 
223 static int jz4740_mmc_acquire_dma_channels(struct jz4740_mmc_host *host)
224 {
225 	host->dma_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
226 	if (IS_ERR(host->dma_tx)) {
227 		dev_err(mmc_dev(host->mmc), "Failed to get dma_tx channel\n");
228 		return PTR_ERR(host->dma_tx);
229 	}
230 
231 	host->dma_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
232 	if (IS_ERR(host->dma_rx)) {
233 		dev_err(mmc_dev(host->mmc), "Failed to get dma_rx channel\n");
234 		dma_release_channel(host->dma_tx);
235 		return PTR_ERR(host->dma_rx);
236 	}
237 
238 	return 0;
239 }
240 
241 static inline struct dma_chan *jz4740_mmc_get_dma_chan(struct jz4740_mmc_host *host,
242 						       struct mmc_data *data)
243 {
244 	return (data->flags & MMC_DATA_READ) ? host->dma_rx : host->dma_tx;
245 }
246 
247 static void jz4740_mmc_dma_unmap(struct jz4740_mmc_host *host,
248 				 struct mmc_data *data)
249 {
250 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
251 	enum dma_data_direction dir = mmc_get_dma_dir(data);
252 
253 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, dir);
254 	data->host_cookie = COOKIE_UNMAPPED;
255 }
256 
257 /* Prepares DMA data for current or next transfer.
258  * A request can be in-flight when this is called.
259  */
260 static int jz4740_mmc_prepare_dma_data(struct jz4740_mmc_host *host,
261 				       struct mmc_data *data,
262 				       int cookie)
263 {
264 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
265 	enum dma_data_direction dir = mmc_get_dma_dir(data);
266 	int sg_count;
267 
268 	if (data->host_cookie == COOKIE_PREMAPPED)
269 		return data->sg_count;
270 
271 	sg_count = dma_map_sg(chan->device->dev,
272 			data->sg,
273 			data->sg_len,
274 			dir);
275 
276 	if (sg_count <= 0) {
277 		dev_err(mmc_dev(host->mmc),
278 			"Failed to map scatterlist for DMA operation\n");
279 		return -EINVAL;
280 	}
281 
282 	data->sg_count = sg_count;
283 	data->host_cookie = cookie;
284 
285 	return data->sg_count;
286 }
287 
288 static int jz4740_mmc_start_dma_transfer(struct jz4740_mmc_host *host,
289 					 struct mmc_data *data)
290 {
291 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
292 	struct dma_async_tx_descriptor *desc;
293 	struct dma_slave_config conf = {
294 		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
295 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
296 		.src_maxburst = JZ4740_MMC_FIFO_HALF_SIZE,
297 		.dst_maxburst = JZ4740_MMC_FIFO_HALF_SIZE,
298 	};
299 	int sg_count;
300 
301 	if (data->flags & MMC_DATA_WRITE) {
302 		conf.direction = DMA_MEM_TO_DEV;
303 		conf.dst_addr = host->mem_res->start + JZ_REG_MMC_TXFIFO;
304 		conf.slave_id = JZ4740_DMA_TYPE_MMC_TRANSMIT;
305 	} else {
306 		conf.direction = DMA_DEV_TO_MEM;
307 		conf.src_addr = host->mem_res->start + JZ_REG_MMC_RXFIFO;
308 		conf.slave_id = JZ4740_DMA_TYPE_MMC_RECEIVE;
309 	}
310 
311 	sg_count = jz4740_mmc_prepare_dma_data(host, data, COOKIE_MAPPED);
312 	if (sg_count < 0)
313 		return sg_count;
314 
315 	dmaengine_slave_config(chan, &conf);
316 	desc = dmaengine_prep_slave_sg(chan, data->sg, sg_count,
317 			conf.direction,
318 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
319 	if (!desc) {
320 		dev_err(mmc_dev(host->mmc),
321 			"Failed to allocate DMA %s descriptor",
322 			 conf.direction == DMA_MEM_TO_DEV ? "TX" : "RX");
323 		goto dma_unmap;
324 	}
325 
326 	dmaengine_submit(desc);
327 	dma_async_issue_pending(chan);
328 
329 	return 0;
330 
331 dma_unmap:
332 	if (data->host_cookie == COOKIE_MAPPED)
333 		jz4740_mmc_dma_unmap(host, data);
334 	return -ENOMEM;
335 }
336 
337 static void jz4740_mmc_pre_request(struct mmc_host *mmc,
338 				   struct mmc_request *mrq)
339 {
340 	struct jz4740_mmc_host *host = mmc_priv(mmc);
341 	struct mmc_data *data = mrq->data;
342 
343 	if (!host->use_dma)
344 		return;
345 
346 	data->host_cookie = COOKIE_UNMAPPED;
347 	if (jz4740_mmc_prepare_dma_data(host, data, COOKIE_PREMAPPED) < 0)
348 		data->host_cookie = COOKIE_UNMAPPED;
349 }
350 
351 static void jz4740_mmc_post_request(struct mmc_host *mmc,
352 				    struct mmc_request *mrq,
353 				    int err)
354 {
355 	struct jz4740_mmc_host *host = mmc_priv(mmc);
356 	struct mmc_data *data = mrq->data;
357 
358 	if (data && data->host_cookie != COOKIE_UNMAPPED)
359 		jz4740_mmc_dma_unmap(host, data);
360 
361 	if (err) {
362 		struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
363 
364 		dmaengine_terminate_all(chan);
365 	}
366 }
367 
368 /*----------------------------------------------------------------------------*/
369 
370 static void jz4740_mmc_set_irq_enabled(struct jz4740_mmc_host *host,
371 	unsigned int irq, bool enabled)
372 {
373 	unsigned long flags;
374 
375 	spin_lock_irqsave(&host->lock, flags);
376 	if (enabled)
377 		host->irq_mask &= ~irq;
378 	else
379 		host->irq_mask |= irq;
380 
381 	jz4740_mmc_write_irq_mask(host, host->irq_mask);
382 	spin_unlock_irqrestore(&host->lock, flags);
383 }
384 
385 static void jz4740_mmc_clock_enable(struct jz4740_mmc_host *host,
386 	bool start_transfer)
387 {
388 	uint16_t val = JZ_MMC_STRPCL_CLOCK_START;
389 
390 	if (start_transfer)
391 		val |= JZ_MMC_STRPCL_START_OP;
392 
393 	writew(val, host->base + JZ_REG_MMC_STRPCL);
394 }
395 
396 static void jz4740_mmc_clock_disable(struct jz4740_mmc_host *host)
397 {
398 	uint32_t status;
399 	unsigned int timeout = 1000;
400 
401 	writew(JZ_MMC_STRPCL_CLOCK_STOP, host->base + JZ_REG_MMC_STRPCL);
402 	do {
403 		status = readl(host->base + JZ_REG_MMC_STATUS);
404 	} while (status & JZ_MMC_STATUS_CLK_EN && --timeout);
405 }
406 
407 static void jz4740_mmc_reset(struct jz4740_mmc_host *host)
408 {
409 	uint32_t status;
410 	unsigned int timeout = 1000;
411 
412 	writew(JZ_MMC_STRPCL_RESET, host->base + JZ_REG_MMC_STRPCL);
413 	udelay(10);
414 	do {
415 		status = readl(host->base + JZ_REG_MMC_STATUS);
416 	} while (status & JZ_MMC_STATUS_IS_RESETTING && --timeout);
417 }
418 
419 static void jz4740_mmc_request_done(struct jz4740_mmc_host *host)
420 {
421 	struct mmc_request *req;
422 	struct mmc_data *data;
423 
424 	req = host->req;
425 	data = req->data;
426 	host->req = NULL;
427 
428 	if (data && data->host_cookie == COOKIE_MAPPED)
429 		jz4740_mmc_dma_unmap(host, data);
430 	mmc_request_done(host->mmc, req);
431 }
432 
433 static unsigned int jz4740_mmc_poll_irq(struct jz4740_mmc_host *host,
434 	unsigned int irq)
435 {
436 	unsigned int timeout = 0x800;
437 	uint32_t status;
438 
439 	do {
440 		status = jz4740_mmc_read_irq_reg(host);
441 	} while (!(status & irq) && --timeout);
442 
443 	if (timeout == 0) {
444 		set_bit(0, &host->waiting);
445 		mod_timer(&host->timeout_timer, jiffies + 5*HZ);
446 		jz4740_mmc_set_irq_enabled(host, irq, true);
447 		return true;
448 	}
449 
450 	return false;
451 }
452 
453 static void jz4740_mmc_transfer_check_state(struct jz4740_mmc_host *host,
454 	struct mmc_data *data)
455 {
456 	int status;
457 
458 	status = readl(host->base + JZ_REG_MMC_STATUS);
459 	if (status & JZ_MMC_STATUS_WRITE_ERROR_MASK) {
460 		if (status & (JZ_MMC_STATUS_TIMEOUT_WRITE)) {
461 			host->req->cmd->error = -ETIMEDOUT;
462 			data->error = -ETIMEDOUT;
463 		} else {
464 			host->req->cmd->error = -EIO;
465 			data->error = -EIO;
466 		}
467 	} else if (status & JZ_MMC_STATUS_READ_ERROR_MASK) {
468 		if (status & (JZ_MMC_STATUS_TIMEOUT_READ)) {
469 			host->req->cmd->error = -ETIMEDOUT;
470 			data->error = -ETIMEDOUT;
471 		} else {
472 			host->req->cmd->error = -EIO;
473 			data->error = -EIO;
474 		}
475 	}
476 }
477 
478 static bool jz4740_mmc_write_data(struct jz4740_mmc_host *host,
479 	struct mmc_data *data)
480 {
481 	struct sg_mapping_iter *miter = &host->miter;
482 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_TXFIFO;
483 	uint32_t *buf;
484 	bool timeout;
485 	size_t i, j;
486 
487 	while (sg_miter_next(miter)) {
488 		buf = miter->addr;
489 		i = miter->length / 4;
490 		j = i / 8;
491 		i = i & 0x7;
492 		while (j) {
493 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_TXFIFO_WR_REQ);
494 			if (unlikely(timeout))
495 				goto poll_timeout;
496 
497 			writel(buf[0], fifo_addr);
498 			writel(buf[1], fifo_addr);
499 			writel(buf[2], fifo_addr);
500 			writel(buf[3], fifo_addr);
501 			writel(buf[4], fifo_addr);
502 			writel(buf[5], fifo_addr);
503 			writel(buf[6], fifo_addr);
504 			writel(buf[7], fifo_addr);
505 			buf += 8;
506 			--j;
507 		}
508 		if (unlikely(i)) {
509 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_TXFIFO_WR_REQ);
510 			if (unlikely(timeout))
511 				goto poll_timeout;
512 
513 			while (i) {
514 				writel(*buf, fifo_addr);
515 				++buf;
516 				--i;
517 			}
518 		}
519 		data->bytes_xfered += miter->length;
520 	}
521 	sg_miter_stop(miter);
522 
523 	return false;
524 
525 poll_timeout:
526 	miter->consumed = (void *)buf - miter->addr;
527 	data->bytes_xfered += miter->consumed;
528 	sg_miter_stop(miter);
529 
530 	return true;
531 }
532 
533 static bool jz4740_mmc_read_data(struct jz4740_mmc_host *host,
534 				struct mmc_data *data)
535 {
536 	struct sg_mapping_iter *miter = &host->miter;
537 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_RXFIFO;
538 	uint32_t *buf;
539 	uint32_t d;
540 	uint32_t status;
541 	size_t i, j;
542 	unsigned int timeout;
543 
544 	while (sg_miter_next(miter)) {
545 		buf = miter->addr;
546 		i = miter->length;
547 		j = i / 32;
548 		i = i & 0x1f;
549 		while (j) {
550 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_RXFIFO_RD_REQ);
551 			if (unlikely(timeout))
552 				goto poll_timeout;
553 
554 			buf[0] = readl(fifo_addr);
555 			buf[1] = readl(fifo_addr);
556 			buf[2] = readl(fifo_addr);
557 			buf[3] = readl(fifo_addr);
558 			buf[4] = readl(fifo_addr);
559 			buf[5] = readl(fifo_addr);
560 			buf[6] = readl(fifo_addr);
561 			buf[7] = readl(fifo_addr);
562 
563 			buf += 8;
564 			--j;
565 		}
566 
567 		if (unlikely(i)) {
568 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_RXFIFO_RD_REQ);
569 			if (unlikely(timeout))
570 				goto poll_timeout;
571 
572 			while (i >= 4) {
573 				*buf++ = readl(fifo_addr);
574 				i -= 4;
575 			}
576 			if (unlikely(i > 0)) {
577 				d = readl(fifo_addr);
578 				memcpy(buf, &d, i);
579 			}
580 		}
581 		data->bytes_xfered += miter->length;
582 
583 		/* This can go away once MIPS implements
584 		 * flush_kernel_dcache_page */
585 		flush_dcache_page(miter->page);
586 	}
587 	sg_miter_stop(miter);
588 
589 	/* For whatever reason there is sometime one word more in the fifo then
590 	 * requested */
591 	timeout = 1000;
592 	status = readl(host->base + JZ_REG_MMC_STATUS);
593 	while (!(status & JZ_MMC_STATUS_DATA_FIFO_EMPTY) && --timeout) {
594 		d = readl(fifo_addr);
595 		status = readl(host->base + JZ_REG_MMC_STATUS);
596 	}
597 
598 	return false;
599 
600 poll_timeout:
601 	miter->consumed = (void *)buf - miter->addr;
602 	data->bytes_xfered += miter->consumed;
603 	sg_miter_stop(miter);
604 
605 	return true;
606 }
607 
608 static void jz4740_mmc_timeout(struct timer_list *t)
609 {
610 	struct jz4740_mmc_host *host = from_timer(host, t, timeout_timer);
611 
612 	if (!test_and_clear_bit(0, &host->waiting))
613 		return;
614 
615 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_END_CMD_RES, false);
616 
617 	host->req->cmd->error = -ETIMEDOUT;
618 	jz4740_mmc_request_done(host);
619 }
620 
621 static void jz4740_mmc_read_response(struct jz4740_mmc_host *host,
622 	struct mmc_command *cmd)
623 {
624 	int i;
625 	uint16_t tmp;
626 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_RESP_FIFO;
627 
628 	if (cmd->flags & MMC_RSP_136) {
629 		tmp = readw(fifo_addr);
630 		for (i = 0; i < 4; ++i) {
631 			cmd->resp[i] = tmp << 24;
632 			tmp = readw(fifo_addr);
633 			cmd->resp[i] |= tmp << 8;
634 			tmp = readw(fifo_addr);
635 			cmd->resp[i] |= tmp >> 8;
636 		}
637 	} else {
638 		cmd->resp[0] = readw(fifo_addr) << 24;
639 		cmd->resp[0] |= readw(fifo_addr) << 8;
640 		cmd->resp[0] |= readw(fifo_addr) & 0xff;
641 	}
642 }
643 
644 static void jz4740_mmc_send_command(struct jz4740_mmc_host *host,
645 	struct mmc_command *cmd)
646 {
647 	uint32_t cmdat = host->cmdat;
648 
649 	host->cmdat &= ~JZ_MMC_CMDAT_INIT;
650 	jz4740_mmc_clock_disable(host);
651 
652 	host->cmd = cmd;
653 
654 	if (cmd->flags & MMC_RSP_BUSY)
655 		cmdat |= JZ_MMC_CMDAT_BUSY;
656 
657 	switch (mmc_resp_type(cmd)) {
658 	case MMC_RSP_R1B:
659 	case MMC_RSP_R1:
660 		cmdat |= JZ_MMC_CMDAT_RSP_R1;
661 		break;
662 	case MMC_RSP_R2:
663 		cmdat |= JZ_MMC_CMDAT_RSP_R2;
664 		break;
665 	case MMC_RSP_R3:
666 		cmdat |= JZ_MMC_CMDAT_RSP_R3;
667 		break;
668 	default:
669 		break;
670 	}
671 
672 	if (cmd->data) {
673 		cmdat |= JZ_MMC_CMDAT_DATA_EN;
674 		if (cmd->data->flags & MMC_DATA_WRITE)
675 			cmdat |= JZ_MMC_CMDAT_WRITE;
676 		if (host->use_dma) {
677 			/*
678 			 * The 4780's MMC controller has integrated DMA ability
679 			 * in addition to being able to use the external DMA
680 			 * controller. It moves DMA control bits to a separate
681 			 * register. The DMA_SEL bit chooses the external
682 			 * controller over the integrated one. Earlier SoCs
683 			 * can only use the external controller, and have a
684 			 * single DMA enable bit in CMDAT.
685 			 */
686 			if (host->version >= JZ_MMC_JZ4780) {
687 				writel(JZ_MMC_DMAC_DMA_EN | JZ_MMC_DMAC_DMA_SEL,
688 				       host->base + JZ_REG_MMC_DMAC);
689 			} else {
690 				cmdat |= JZ_MMC_CMDAT_DMA_EN;
691 			}
692 		} else if (host->version >= JZ_MMC_JZ4780) {
693 			writel(0, host->base + JZ_REG_MMC_DMAC);
694 		}
695 
696 		writew(cmd->data->blksz, host->base + JZ_REG_MMC_BLKLEN);
697 		writew(cmd->data->blocks, host->base + JZ_REG_MMC_NOB);
698 	}
699 
700 	writeb(cmd->opcode, host->base + JZ_REG_MMC_CMD);
701 	writel(cmd->arg, host->base + JZ_REG_MMC_ARG);
702 	writel(cmdat, host->base + JZ_REG_MMC_CMDAT);
703 
704 	jz4740_mmc_clock_enable(host, 1);
705 }
706 
707 static void jz_mmc_prepare_data_transfer(struct jz4740_mmc_host *host)
708 {
709 	struct mmc_command *cmd = host->req->cmd;
710 	struct mmc_data *data = cmd->data;
711 	int direction;
712 
713 	if (data->flags & MMC_DATA_READ)
714 		direction = SG_MITER_TO_SG;
715 	else
716 		direction = SG_MITER_FROM_SG;
717 
718 	sg_miter_start(&host->miter, data->sg, data->sg_len, direction);
719 }
720 
721 
722 static irqreturn_t jz_mmc_irq_worker(int irq, void *devid)
723 {
724 	struct jz4740_mmc_host *host = (struct jz4740_mmc_host *)devid;
725 	struct mmc_command *cmd = host->req->cmd;
726 	struct mmc_request *req = host->req;
727 	struct mmc_data *data = cmd->data;
728 	bool timeout = false;
729 
730 	if (cmd->error)
731 		host->state = JZ4740_MMC_STATE_DONE;
732 
733 	switch (host->state) {
734 	case JZ4740_MMC_STATE_READ_RESPONSE:
735 		if (cmd->flags & MMC_RSP_PRESENT)
736 			jz4740_mmc_read_response(host, cmd);
737 
738 		if (!data)
739 			break;
740 
741 		jz_mmc_prepare_data_transfer(host);
742 		/* fall through */
743 
744 	case JZ4740_MMC_STATE_TRANSFER_DATA:
745 		if (host->use_dma) {
746 			/* Use DMA if enabled.
747 			 * Data transfer direction is defined later by
748 			 * relying on data flags in
749 			 * jz4740_mmc_prepare_dma_data() and
750 			 * jz4740_mmc_start_dma_transfer().
751 			 */
752 			timeout = jz4740_mmc_start_dma_transfer(host, data);
753 			data->bytes_xfered = data->blocks * data->blksz;
754 		} else if (data->flags & MMC_DATA_READ)
755 			/* Use PIO if DMA is not enabled.
756 			 * Data transfer direction was defined before
757 			 * by relying on data flags in
758 			 * jz_mmc_prepare_data_transfer().
759 			 */
760 			timeout = jz4740_mmc_read_data(host, data);
761 		else
762 			timeout = jz4740_mmc_write_data(host, data);
763 
764 		if (unlikely(timeout)) {
765 			host->state = JZ4740_MMC_STATE_TRANSFER_DATA;
766 			break;
767 		}
768 
769 		jz4740_mmc_transfer_check_state(host, data);
770 
771 		timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_DATA_TRAN_DONE);
772 		if (unlikely(timeout)) {
773 			host->state = JZ4740_MMC_STATE_SEND_STOP;
774 			break;
775 		}
776 		jz4740_mmc_write_irq_reg(host, JZ_MMC_IRQ_DATA_TRAN_DONE);
777 		/* fall through */
778 
779 	case JZ4740_MMC_STATE_SEND_STOP:
780 		if (!req->stop)
781 			break;
782 
783 		jz4740_mmc_send_command(host, req->stop);
784 
785 		if (mmc_resp_type(req->stop) & MMC_RSP_BUSY) {
786 			timeout = jz4740_mmc_poll_irq(host,
787 						      JZ_MMC_IRQ_PRG_DONE);
788 			if (timeout) {
789 				host->state = JZ4740_MMC_STATE_DONE;
790 				break;
791 			}
792 		}
793 	case JZ4740_MMC_STATE_DONE:
794 		break;
795 	}
796 
797 	if (!timeout)
798 		jz4740_mmc_request_done(host);
799 
800 	return IRQ_HANDLED;
801 }
802 
803 static irqreturn_t jz_mmc_irq(int irq, void *devid)
804 {
805 	struct jz4740_mmc_host *host = devid;
806 	struct mmc_command *cmd = host->cmd;
807 	uint32_t irq_reg, status, tmp;
808 
809 	status = readl(host->base + JZ_REG_MMC_STATUS);
810 	irq_reg = jz4740_mmc_read_irq_reg(host);
811 
812 	tmp = irq_reg;
813 	irq_reg &= ~host->irq_mask;
814 
815 	tmp &= ~(JZ_MMC_IRQ_TXFIFO_WR_REQ | JZ_MMC_IRQ_RXFIFO_RD_REQ |
816 		JZ_MMC_IRQ_PRG_DONE | JZ_MMC_IRQ_DATA_TRAN_DONE);
817 
818 	if (tmp != irq_reg)
819 		jz4740_mmc_write_irq_reg(host, tmp & ~irq_reg);
820 
821 	if (irq_reg & JZ_MMC_IRQ_SDIO) {
822 		jz4740_mmc_write_irq_reg(host, JZ_MMC_IRQ_SDIO);
823 		mmc_signal_sdio_irq(host->mmc);
824 		irq_reg &= ~JZ_MMC_IRQ_SDIO;
825 	}
826 
827 	if (host->req && cmd && irq_reg) {
828 		if (test_and_clear_bit(0, &host->waiting)) {
829 			del_timer(&host->timeout_timer);
830 
831 			if (status & JZ_MMC_STATUS_TIMEOUT_RES) {
832 					cmd->error = -ETIMEDOUT;
833 			} else if (status & JZ_MMC_STATUS_CRC_RES_ERR) {
834 					cmd->error = -EIO;
835 			} else if (status & (JZ_MMC_STATUS_CRC_READ_ERROR |
836 				    JZ_MMC_STATUS_CRC_WRITE_ERROR)) {
837 					if (cmd->data)
838 							cmd->data->error = -EIO;
839 					cmd->error = -EIO;
840 			}
841 
842 			jz4740_mmc_set_irq_enabled(host, irq_reg, false);
843 			jz4740_mmc_write_irq_reg(host, irq_reg);
844 
845 			return IRQ_WAKE_THREAD;
846 		}
847 	}
848 
849 	return IRQ_HANDLED;
850 }
851 
852 static int jz4740_mmc_set_clock_rate(struct jz4740_mmc_host *host, int rate)
853 {
854 	int div = 0;
855 	int real_rate;
856 
857 	jz4740_mmc_clock_disable(host);
858 	clk_set_rate(host->clk, host->mmc->f_max);
859 
860 	real_rate = clk_get_rate(host->clk);
861 
862 	while (real_rate > rate && div < 7) {
863 		++div;
864 		real_rate >>= 1;
865 	}
866 
867 	writew(div, host->base + JZ_REG_MMC_CLKRT);
868 	return real_rate;
869 }
870 
871 static void jz4740_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
872 {
873 	struct jz4740_mmc_host *host = mmc_priv(mmc);
874 
875 	host->req = req;
876 
877 	jz4740_mmc_write_irq_reg(host, ~0);
878 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_END_CMD_RES, true);
879 
880 	host->state = JZ4740_MMC_STATE_READ_RESPONSE;
881 	set_bit(0, &host->waiting);
882 	mod_timer(&host->timeout_timer, jiffies + 5*HZ);
883 	jz4740_mmc_send_command(host, req->cmd);
884 }
885 
886 static void jz4740_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
887 {
888 	struct jz4740_mmc_host *host = mmc_priv(mmc);
889 	if (ios->clock)
890 		jz4740_mmc_set_clock_rate(host, ios->clock);
891 
892 	switch (ios->power_mode) {
893 	case MMC_POWER_UP:
894 		jz4740_mmc_reset(host);
895 		if (!IS_ERR(mmc->supply.vmmc))
896 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
897 		host->cmdat |= JZ_MMC_CMDAT_INIT;
898 		clk_prepare_enable(host->clk);
899 		break;
900 	case MMC_POWER_ON:
901 		break;
902 	default:
903 		if (!IS_ERR(mmc->supply.vmmc))
904 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
905 		clk_disable_unprepare(host->clk);
906 		break;
907 	}
908 
909 	switch (ios->bus_width) {
910 	case MMC_BUS_WIDTH_1:
911 		host->cmdat &= ~JZ_MMC_CMDAT_BUS_WIDTH_4BIT;
912 		break;
913 	case MMC_BUS_WIDTH_4:
914 		host->cmdat |= JZ_MMC_CMDAT_BUS_WIDTH_4BIT;
915 		break;
916 	default:
917 		break;
918 	}
919 }
920 
921 static void jz4740_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
922 {
923 	struct jz4740_mmc_host *host = mmc_priv(mmc);
924 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_SDIO, enable);
925 }
926 
927 static const struct mmc_host_ops jz4740_mmc_ops = {
928 	.request	= jz4740_mmc_request,
929 	.pre_req	= jz4740_mmc_pre_request,
930 	.post_req	= jz4740_mmc_post_request,
931 	.set_ios	= jz4740_mmc_set_ios,
932 	.get_ro		= mmc_gpio_get_ro,
933 	.get_cd		= mmc_gpio_get_cd,
934 	.enable_sdio_irq = jz4740_mmc_enable_sdio_irq,
935 };
936 
937 static const struct of_device_id jz4740_mmc_of_match[] = {
938 	{ .compatible = "ingenic,jz4740-mmc", .data = (void *) JZ_MMC_JZ4740 },
939 	{ .compatible = "ingenic,jz4725b-mmc", .data = (void *)JZ_MMC_JZ4725B },
940 	{ .compatible = "ingenic,jz4780-mmc", .data = (void *) JZ_MMC_JZ4780 },
941 	{},
942 };
943 MODULE_DEVICE_TABLE(of, jz4740_mmc_of_match);
944 
945 static int jz4740_mmc_probe(struct platform_device* pdev)
946 {
947 	int ret;
948 	struct mmc_host *mmc;
949 	struct jz4740_mmc_host *host;
950 	const struct of_device_id *match;
951 
952 	mmc = mmc_alloc_host(sizeof(struct jz4740_mmc_host), &pdev->dev);
953 	if (!mmc) {
954 		dev_err(&pdev->dev, "Failed to alloc mmc host structure\n");
955 		return -ENOMEM;
956 	}
957 
958 	host = mmc_priv(mmc);
959 
960 	match = of_match_device(jz4740_mmc_of_match, &pdev->dev);
961 	if (match) {
962 		host->version = (enum jz4740_mmc_version)match->data;
963 	} else {
964 		/* JZ4740 should be the only one using legacy probe */
965 		host->version = JZ_MMC_JZ4740;
966 	}
967 
968 	ret = mmc_of_parse(mmc);
969 	if (ret) {
970 		if (ret != -EPROBE_DEFER)
971 			dev_err(&pdev->dev,
972 				"could not parse device properties: %d\n", ret);
973 		goto err_free_host;
974 	}
975 
976 	mmc_regulator_get_supply(mmc);
977 
978 	host->irq = platform_get_irq(pdev, 0);
979 	if (host->irq < 0) {
980 		ret = host->irq;
981 		dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
982 		goto err_free_host;
983 	}
984 
985 	host->clk = devm_clk_get(&pdev->dev, "mmc");
986 	if (IS_ERR(host->clk)) {
987 		ret = PTR_ERR(host->clk);
988 		dev_err(&pdev->dev, "Failed to get mmc clock\n");
989 		goto err_free_host;
990 	}
991 
992 	host->mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
993 	host->base = devm_ioremap_resource(&pdev->dev, host->mem_res);
994 	if (IS_ERR(host->base)) {
995 		ret = PTR_ERR(host->base);
996 		dev_err(&pdev->dev, "Failed to ioremap base memory\n");
997 		goto err_free_host;
998 	}
999 
1000 	mmc->ops = &jz4740_mmc_ops;
1001 	if (!mmc->f_max)
1002 		mmc->f_max = JZ_MMC_CLK_RATE;
1003 	mmc->f_min = mmc->f_max / 128;
1004 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1005 
1006 	mmc->max_blk_size = (1 << 10) - 1;
1007 	mmc->max_blk_count = (1 << 15) - 1;
1008 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1009 
1010 	mmc->max_segs = 128;
1011 	mmc->max_seg_size = mmc->max_req_size;
1012 
1013 	host->mmc = mmc;
1014 	host->pdev = pdev;
1015 	spin_lock_init(&host->lock);
1016 	host->irq_mask = ~0;
1017 
1018 	jz4740_mmc_reset(host);
1019 
1020 	ret = request_threaded_irq(host->irq, jz_mmc_irq, jz_mmc_irq_worker, 0,
1021 			dev_name(&pdev->dev), host);
1022 	if (ret) {
1023 		dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
1024 		goto err_free_host;
1025 	}
1026 
1027 	jz4740_mmc_clock_disable(host);
1028 	timer_setup(&host->timeout_timer, jz4740_mmc_timeout, 0);
1029 
1030 	ret = jz4740_mmc_acquire_dma_channels(host);
1031 	if (ret == -EPROBE_DEFER)
1032 		goto err_free_irq;
1033 	host->use_dma = !ret;
1034 
1035 	platform_set_drvdata(pdev, host);
1036 	ret = mmc_add_host(mmc);
1037 
1038 	if (ret) {
1039 		dev_err(&pdev->dev, "Failed to add mmc host: %d\n", ret);
1040 		goto err_release_dma;
1041 	}
1042 	dev_info(&pdev->dev, "JZ SD/MMC card driver registered\n");
1043 
1044 	dev_info(&pdev->dev, "Using %s, %d-bit mode\n",
1045 		 host->use_dma ? "DMA" : "PIO",
1046 		 (mmc->caps & MMC_CAP_4_BIT_DATA) ? 4 : 1);
1047 
1048 	return 0;
1049 
1050 err_release_dma:
1051 	if (host->use_dma)
1052 		jz4740_mmc_release_dma_channels(host);
1053 err_free_irq:
1054 	free_irq(host->irq, host);
1055 err_free_host:
1056 	mmc_free_host(mmc);
1057 
1058 	return ret;
1059 }
1060 
1061 static int jz4740_mmc_remove(struct platform_device *pdev)
1062 {
1063 	struct jz4740_mmc_host *host = platform_get_drvdata(pdev);
1064 
1065 	del_timer_sync(&host->timeout_timer);
1066 	jz4740_mmc_set_irq_enabled(host, 0xff, false);
1067 	jz4740_mmc_reset(host);
1068 
1069 	mmc_remove_host(host->mmc);
1070 
1071 	free_irq(host->irq, host);
1072 
1073 	if (host->use_dma)
1074 		jz4740_mmc_release_dma_channels(host);
1075 
1076 	mmc_free_host(host->mmc);
1077 
1078 	return 0;
1079 }
1080 
1081 #ifdef CONFIG_PM_SLEEP
1082 
1083 static int jz4740_mmc_suspend(struct device *dev)
1084 {
1085 	return pinctrl_pm_select_sleep_state(dev);
1086 }
1087 
1088 static int jz4740_mmc_resume(struct device *dev)
1089 {
1090 	return pinctrl_pm_select_default_state(dev);
1091 }
1092 
1093 static SIMPLE_DEV_PM_OPS(jz4740_mmc_pm_ops, jz4740_mmc_suspend,
1094 	jz4740_mmc_resume);
1095 #define JZ4740_MMC_PM_OPS (&jz4740_mmc_pm_ops)
1096 #else
1097 #define JZ4740_MMC_PM_OPS NULL
1098 #endif
1099 
1100 static struct platform_driver jz4740_mmc_driver = {
1101 	.probe = jz4740_mmc_probe,
1102 	.remove = jz4740_mmc_remove,
1103 	.driver = {
1104 		.name = "jz4740-mmc",
1105 		.of_match_table = of_match_ptr(jz4740_mmc_of_match),
1106 		.pm = JZ4740_MMC_PM_OPS,
1107 	},
1108 };
1109 
1110 module_platform_driver(jz4740_mmc_driver);
1111 
1112 MODULE_DESCRIPTION("JZ4740 SD/MMC controller driver");
1113 MODULE_LICENSE("GPL");
1114 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
1115