xref: /openbmc/linux/drivers/mmc/host/jz4740_mmc.c (revision 86db9f28)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
4  *  Copyright (C) 2013, Imagination Technologies
5  *
6  *  JZ4740 SD/MMC controller driver
7  */
8 
9 #include <linux/bitops.h>
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/dmaengine.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/err.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/irq.h>
18 #include <linux/mmc/host.h>
19 #include <linux/mmc/slot-gpio.h>
20 #include <linux/module.h>
21 #include <linux/of_device.h>
22 #include <linux/pinctrl/consumer.h>
23 #include <linux/platform_device.h>
24 #include <linux/scatterlist.h>
25 
26 #include <asm/cacheflush.h>
27 
28 #define JZ_REG_MMC_STRPCL	0x00
29 #define JZ_REG_MMC_STATUS	0x04
30 #define JZ_REG_MMC_CLKRT	0x08
31 #define JZ_REG_MMC_CMDAT	0x0C
32 #define JZ_REG_MMC_RESTO	0x10
33 #define JZ_REG_MMC_RDTO		0x14
34 #define JZ_REG_MMC_BLKLEN	0x18
35 #define JZ_REG_MMC_NOB		0x1C
36 #define JZ_REG_MMC_SNOB		0x20
37 #define JZ_REG_MMC_IMASK	0x24
38 #define JZ_REG_MMC_IREG		0x28
39 #define JZ_REG_MMC_CMD		0x2C
40 #define JZ_REG_MMC_ARG		0x30
41 #define JZ_REG_MMC_RESP_FIFO	0x34
42 #define JZ_REG_MMC_RXFIFO	0x38
43 #define JZ_REG_MMC_TXFIFO	0x3C
44 #define JZ_REG_MMC_DMAC		0x44
45 
46 #define JZ_MMC_STRPCL_EXIT_MULTIPLE BIT(7)
47 #define JZ_MMC_STRPCL_EXIT_TRANSFER BIT(6)
48 #define JZ_MMC_STRPCL_START_READWAIT BIT(5)
49 #define JZ_MMC_STRPCL_STOP_READWAIT BIT(4)
50 #define JZ_MMC_STRPCL_RESET BIT(3)
51 #define JZ_MMC_STRPCL_START_OP BIT(2)
52 #define JZ_MMC_STRPCL_CLOCK_CONTROL (BIT(1) | BIT(0))
53 #define JZ_MMC_STRPCL_CLOCK_STOP BIT(0)
54 #define JZ_MMC_STRPCL_CLOCK_START BIT(1)
55 
56 
57 #define JZ_MMC_STATUS_IS_RESETTING BIT(15)
58 #define JZ_MMC_STATUS_SDIO_INT_ACTIVE BIT(14)
59 #define JZ_MMC_STATUS_PRG_DONE BIT(13)
60 #define JZ_MMC_STATUS_DATA_TRAN_DONE BIT(12)
61 #define JZ_MMC_STATUS_END_CMD_RES BIT(11)
62 #define JZ_MMC_STATUS_DATA_FIFO_AFULL BIT(10)
63 #define JZ_MMC_STATUS_IS_READWAIT BIT(9)
64 #define JZ_MMC_STATUS_CLK_EN BIT(8)
65 #define JZ_MMC_STATUS_DATA_FIFO_FULL BIT(7)
66 #define JZ_MMC_STATUS_DATA_FIFO_EMPTY BIT(6)
67 #define JZ_MMC_STATUS_CRC_RES_ERR BIT(5)
68 #define JZ_MMC_STATUS_CRC_READ_ERROR BIT(4)
69 #define JZ_MMC_STATUS_TIMEOUT_WRITE BIT(3)
70 #define JZ_MMC_STATUS_CRC_WRITE_ERROR BIT(2)
71 #define JZ_MMC_STATUS_TIMEOUT_RES BIT(1)
72 #define JZ_MMC_STATUS_TIMEOUT_READ BIT(0)
73 
74 #define JZ_MMC_STATUS_READ_ERROR_MASK (BIT(4) | BIT(0))
75 #define JZ_MMC_STATUS_WRITE_ERROR_MASK (BIT(3) | BIT(2))
76 
77 
78 #define JZ_MMC_CMDAT_IO_ABORT BIT(11)
79 #define JZ_MMC_CMDAT_BUS_WIDTH_4BIT BIT(10)
80 #define JZ_MMC_CMDAT_DMA_EN BIT(8)
81 #define JZ_MMC_CMDAT_INIT BIT(7)
82 #define JZ_MMC_CMDAT_BUSY BIT(6)
83 #define JZ_MMC_CMDAT_STREAM BIT(5)
84 #define JZ_MMC_CMDAT_WRITE BIT(4)
85 #define JZ_MMC_CMDAT_DATA_EN BIT(3)
86 #define JZ_MMC_CMDAT_RESPONSE_FORMAT (BIT(2) | BIT(1) | BIT(0))
87 #define JZ_MMC_CMDAT_RSP_R1 1
88 #define JZ_MMC_CMDAT_RSP_R2 2
89 #define JZ_MMC_CMDAT_RSP_R3 3
90 
91 #define JZ_MMC_IRQ_SDIO BIT(7)
92 #define JZ_MMC_IRQ_TXFIFO_WR_REQ BIT(6)
93 #define JZ_MMC_IRQ_RXFIFO_RD_REQ BIT(5)
94 #define JZ_MMC_IRQ_END_CMD_RES BIT(2)
95 #define JZ_MMC_IRQ_PRG_DONE BIT(1)
96 #define JZ_MMC_IRQ_DATA_TRAN_DONE BIT(0)
97 
98 #define JZ_MMC_DMAC_DMA_SEL BIT(1)
99 #define JZ_MMC_DMAC_DMA_EN BIT(0)
100 
101 #define JZ_MMC_CLK_RATE 24000000
102 
103 enum jz4740_mmc_version {
104 	JZ_MMC_JZ4740,
105 	JZ_MMC_JZ4725B,
106 	JZ_MMC_JZ4780,
107 };
108 
109 enum jz4740_mmc_state {
110 	JZ4740_MMC_STATE_READ_RESPONSE,
111 	JZ4740_MMC_STATE_TRANSFER_DATA,
112 	JZ4740_MMC_STATE_SEND_STOP,
113 	JZ4740_MMC_STATE_DONE,
114 };
115 
116 /*
117  * The MMC core allows to prepare a mmc_request while another mmc_request
118  * is in-flight. This is used via the pre_req/post_req hooks.
119  * This driver uses the pre_req/post_req hooks to map/unmap the mmc_request.
120  * Following what other drivers do (sdhci, dw_mmc) we use the following cookie
121  * flags to keep track of the mmc_request mapping state.
122  *
123  * COOKIE_UNMAPPED: the request is not mapped.
124  * COOKIE_PREMAPPED: the request was mapped in pre_req,
125  * and should be unmapped in post_req.
126  * COOKIE_MAPPED: the request was mapped in the irq handler,
127  * and should be unmapped before mmc_request_done is called..
128  */
129 enum jz4780_cookie {
130 	COOKIE_UNMAPPED = 0,
131 	COOKIE_PREMAPPED,
132 	COOKIE_MAPPED,
133 };
134 
135 struct jz4740_mmc_host {
136 	struct mmc_host *mmc;
137 	struct platform_device *pdev;
138 	struct clk *clk;
139 
140 	enum jz4740_mmc_version version;
141 
142 	int irq;
143 	int card_detect_irq;
144 
145 	void __iomem *base;
146 	struct resource *mem_res;
147 	struct mmc_request *req;
148 	struct mmc_command *cmd;
149 
150 	unsigned long waiting;
151 
152 	uint32_t cmdat;
153 
154 	uint32_t irq_mask;
155 
156 	spinlock_t lock;
157 
158 	struct timer_list timeout_timer;
159 	struct sg_mapping_iter miter;
160 	enum jz4740_mmc_state state;
161 
162 	/* DMA support */
163 	struct dma_chan *dma_rx;
164 	struct dma_chan *dma_tx;
165 	bool use_dma;
166 
167 /* The DMA trigger level is 8 words, that is to say, the DMA read
168  * trigger is when data words in MSC_RXFIFO is >= 8 and the DMA write
169  * trigger is when data words in MSC_TXFIFO is < 8.
170  */
171 #define JZ4740_MMC_FIFO_HALF_SIZE 8
172 };
173 
174 static void jz4740_mmc_write_irq_mask(struct jz4740_mmc_host *host,
175 				      uint32_t val)
176 {
177 	if (host->version >= JZ_MMC_JZ4725B)
178 		return writel(val, host->base + JZ_REG_MMC_IMASK);
179 	else
180 		return writew(val, host->base + JZ_REG_MMC_IMASK);
181 }
182 
183 static void jz4740_mmc_write_irq_reg(struct jz4740_mmc_host *host,
184 				     uint32_t val)
185 {
186 	if (host->version >= JZ_MMC_JZ4780)
187 		writel(val, host->base + JZ_REG_MMC_IREG);
188 	else
189 		writew(val, host->base + JZ_REG_MMC_IREG);
190 }
191 
192 static uint32_t jz4740_mmc_read_irq_reg(struct jz4740_mmc_host *host)
193 {
194 	if (host->version >= JZ_MMC_JZ4780)
195 		return readl(host->base + JZ_REG_MMC_IREG);
196 	else
197 		return readw(host->base + JZ_REG_MMC_IREG);
198 }
199 
200 /*----------------------------------------------------------------------------*/
201 /* DMA infrastructure */
202 
203 static void jz4740_mmc_release_dma_channels(struct jz4740_mmc_host *host)
204 {
205 	if (!host->use_dma)
206 		return;
207 
208 	dma_release_channel(host->dma_tx);
209 	dma_release_channel(host->dma_rx);
210 }
211 
212 static int jz4740_mmc_acquire_dma_channels(struct jz4740_mmc_host *host)
213 {
214 	host->dma_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
215 	if (IS_ERR(host->dma_tx)) {
216 		dev_err(mmc_dev(host->mmc), "Failed to get dma_tx channel\n");
217 		return PTR_ERR(host->dma_tx);
218 	}
219 
220 	host->dma_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
221 	if (IS_ERR(host->dma_rx)) {
222 		dev_err(mmc_dev(host->mmc), "Failed to get dma_rx channel\n");
223 		dma_release_channel(host->dma_tx);
224 		return PTR_ERR(host->dma_rx);
225 	}
226 
227 	return 0;
228 }
229 
230 static inline struct dma_chan *jz4740_mmc_get_dma_chan(struct jz4740_mmc_host *host,
231 						       struct mmc_data *data)
232 {
233 	return (data->flags & MMC_DATA_READ) ? host->dma_rx : host->dma_tx;
234 }
235 
236 static void jz4740_mmc_dma_unmap(struct jz4740_mmc_host *host,
237 				 struct mmc_data *data)
238 {
239 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
240 	enum dma_data_direction dir = mmc_get_dma_dir(data);
241 
242 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, dir);
243 	data->host_cookie = COOKIE_UNMAPPED;
244 }
245 
246 /* Prepares DMA data for current or next transfer.
247  * A request can be in-flight when this is called.
248  */
249 static int jz4740_mmc_prepare_dma_data(struct jz4740_mmc_host *host,
250 				       struct mmc_data *data,
251 				       int cookie)
252 {
253 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
254 	enum dma_data_direction dir = mmc_get_dma_dir(data);
255 	int sg_count;
256 
257 	if (data->host_cookie == COOKIE_PREMAPPED)
258 		return data->sg_count;
259 
260 	sg_count = dma_map_sg(chan->device->dev,
261 			data->sg,
262 			data->sg_len,
263 			dir);
264 
265 	if (sg_count <= 0) {
266 		dev_err(mmc_dev(host->mmc),
267 			"Failed to map scatterlist for DMA operation\n");
268 		return -EINVAL;
269 	}
270 
271 	data->sg_count = sg_count;
272 	data->host_cookie = cookie;
273 
274 	return data->sg_count;
275 }
276 
277 static int jz4740_mmc_start_dma_transfer(struct jz4740_mmc_host *host,
278 					 struct mmc_data *data)
279 {
280 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
281 	struct dma_async_tx_descriptor *desc;
282 	struct dma_slave_config conf = {
283 		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
284 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
285 		.src_maxburst = JZ4740_MMC_FIFO_HALF_SIZE,
286 		.dst_maxburst = JZ4740_MMC_FIFO_HALF_SIZE,
287 	};
288 	int sg_count;
289 
290 	if (data->flags & MMC_DATA_WRITE) {
291 		conf.direction = DMA_MEM_TO_DEV;
292 		conf.dst_addr = host->mem_res->start + JZ_REG_MMC_TXFIFO;
293 	} else {
294 		conf.direction = DMA_DEV_TO_MEM;
295 		conf.src_addr = host->mem_res->start + JZ_REG_MMC_RXFIFO;
296 	}
297 
298 	sg_count = jz4740_mmc_prepare_dma_data(host, data, COOKIE_MAPPED);
299 	if (sg_count < 0)
300 		return sg_count;
301 
302 	dmaengine_slave_config(chan, &conf);
303 	desc = dmaengine_prep_slave_sg(chan, data->sg, sg_count,
304 			conf.direction,
305 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
306 	if (!desc) {
307 		dev_err(mmc_dev(host->mmc),
308 			"Failed to allocate DMA %s descriptor",
309 			 conf.direction == DMA_MEM_TO_DEV ? "TX" : "RX");
310 		goto dma_unmap;
311 	}
312 
313 	dmaengine_submit(desc);
314 	dma_async_issue_pending(chan);
315 
316 	return 0;
317 
318 dma_unmap:
319 	if (data->host_cookie == COOKIE_MAPPED)
320 		jz4740_mmc_dma_unmap(host, data);
321 	return -ENOMEM;
322 }
323 
324 static void jz4740_mmc_pre_request(struct mmc_host *mmc,
325 				   struct mmc_request *mrq)
326 {
327 	struct jz4740_mmc_host *host = mmc_priv(mmc);
328 	struct mmc_data *data = mrq->data;
329 
330 	if (!host->use_dma)
331 		return;
332 
333 	data->host_cookie = COOKIE_UNMAPPED;
334 	if (jz4740_mmc_prepare_dma_data(host, data, COOKIE_PREMAPPED) < 0)
335 		data->host_cookie = COOKIE_UNMAPPED;
336 }
337 
338 static void jz4740_mmc_post_request(struct mmc_host *mmc,
339 				    struct mmc_request *mrq,
340 				    int err)
341 {
342 	struct jz4740_mmc_host *host = mmc_priv(mmc);
343 	struct mmc_data *data = mrq->data;
344 
345 	if (data && data->host_cookie != COOKIE_UNMAPPED)
346 		jz4740_mmc_dma_unmap(host, data);
347 
348 	if (err) {
349 		struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
350 
351 		dmaengine_terminate_all(chan);
352 	}
353 }
354 
355 /*----------------------------------------------------------------------------*/
356 
357 static void jz4740_mmc_set_irq_enabled(struct jz4740_mmc_host *host,
358 	unsigned int irq, bool enabled)
359 {
360 	unsigned long flags;
361 
362 	spin_lock_irqsave(&host->lock, flags);
363 	if (enabled)
364 		host->irq_mask &= ~irq;
365 	else
366 		host->irq_mask |= irq;
367 
368 	jz4740_mmc_write_irq_mask(host, host->irq_mask);
369 	spin_unlock_irqrestore(&host->lock, flags);
370 }
371 
372 static void jz4740_mmc_clock_enable(struct jz4740_mmc_host *host,
373 	bool start_transfer)
374 {
375 	uint16_t val = JZ_MMC_STRPCL_CLOCK_START;
376 
377 	if (start_transfer)
378 		val |= JZ_MMC_STRPCL_START_OP;
379 
380 	writew(val, host->base + JZ_REG_MMC_STRPCL);
381 }
382 
383 static void jz4740_mmc_clock_disable(struct jz4740_mmc_host *host)
384 {
385 	uint32_t status;
386 	unsigned int timeout = 1000;
387 
388 	writew(JZ_MMC_STRPCL_CLOCK_STOP, host->base + JZ_REG_MMC_STRPCL);
389 	do {
390 		status = readl(host->base + JZ_REG_MMC_STATUS);
391 	} while (status & JZ_MMC_STATUS_CLK_EN && --timeout);
392 }
393 
394 static void jz4740_mmc_reset(struct jz4740_mmc_host *host)
395 {
396 	uint32_t status;
397 	unsigned int timeout = 1000;
398 
399 	writew(JZ_MMC_STRPCL_RESET, host->base + JZ_REG_MMC_STRPCL);
400 	udelay(10);
401 	do {
402 		status = readl(host->base + JZ_REG_MMC_STATUS);
403 	} while (status & JZ_MMC_STATUS_IS_RESETTING && --timeout);
404 }
405 
406 static void jz4740_mmc_request_done(struct jz4740_mmc_host *host)
407 {
408 	struct mmc_request *req;
409 	struct mmc_data *data;
410 
411 	req = host->req;
412 	data = req->data;
413 	host->req = NULL;
414 
415 	if (data && data->host_cookie == COOKIE_MAPPED)
416 		jz4740_mmc_dma_unmap(host, data);
417 	mmc_request_done(host->mmc, req);
418 }
419 
420 static unsigned int jz4740_mmc_poll_irq(struct jz4740_mmc_host *host,
421 	unsigned int irq)
422 {
423 	unsigned int timeout = 0x800;
424 	uint32_t status;
425 
426 	do {
427 		status = jz4740_mmc_read_irq_reg(host);
428 	} while (!(status & irq) && --timeout);
429 
430 	if (timeout == 0) {
431 		set_bit(0, &host->waiting);
432 		mod_timer(&host->timeout_timer, jiffies + 5*HZ);
433 		jz4740_mmc_set_irq_enabled(host, irq, true);
434 		return true;
435 	}
436 
437 	return false;
438 }
439 
440 static void jz4740_mmc_transfer_check_state(struct jz4740_mmc_host *host,
441 	struct mmc_data *data)
442 {
443 	int status;
444 
445 	status = readl(host->base + JZ_REG_MMC_STATUS);
446 	if (status & JZ_MMC_STATUS_WRITE_ERROR_MASK) {
447 		if (status & (JZ_MMC_STATUS_TIMEOUT_WRITE)) {
448 			host->req->cmd->error = -ETIMEDOUT;
449 			data->error = -ETIMEDOUT;
450 		} else {
451 			host->req->cmd->error = -EIO;
452 			data->error = -EIO;
453 		}
454 	} else if (status & JZ_MMC_STATUS_READ_ERROR_MASK) {
455 		if (status & (JZ_MMC_STATUS_TIMEOUT_READ)) {
456 			host->req->cmd->error = -ETIMEDOUT;
457 			data->error = -ETIMEDOUT;
458 		} else {
459 			host->req->cmd->error = -EIO;
460 			data->error = -EIO;
461 		}
462 	}
463 }
464 
465 static bool jz4740_mmc_write_data(struct jz4740_mmc_host *host,
466 	struct mmc_data *data)
467 {
468 	struct sg_mapping_iter *miter = &host->miter;
469 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_TXFIFO;
470 	uint32_t *buf;
471 	bool timeout;
472 	size_t i, j;
473 
474 	while (sg_miter_next(miter)) {
475 		buf = miter->addr;
476 		i = miter->length / 4;
477 		j = i / 8;
478 		i = i & 0x7;
479 		while (j) {
480 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_TXFIFO_WR_REQ);
481 			if (unlikely(timeout))
482 				goto poll_timeout;
483 
484 			writel(buf[0], fifo_addr);
485 			writel(buf[1], fifo_addr);
486 			writel(buf[2], fifo_addr);
487 			writel(buf[3], fifo_addr);
488 			writel(buf[4], fifo_addr);
489 			writel(buf[5], fifo_addr);
490 			writel(buf[6], fifo_addr);
491 			writel(buf[7], fifo_addr);
492 			buf += 8;
493 			--j;
494 		}
495 		if (unlikely(i)) {
496 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_TXFIFO_WR_REQ);
497 			if (unlikely(timeout))
498 				goto poll_timeout;
499 
500 			while (i) {
501 				writel(*buf, fifo_addr);
502 				++buf;
503 				--i;
504 			}
505 		}
506 		data->bytes_xfered += miter->length;
507 	}
508 	sg_miter_stop(miter);
509 
510 	return false;
511 
512 poll_timeout:
513 	miter->consumed = (void *)buf - miter->addr;
514 	data->bytes_xfered += miter->consumed;
515 	sg_miter_stop(miter);
516 
517 	return true;
518 }
519 
520 static bool jz4740_mmc_read_data(struct jz4740_mmc_host *host,
521 				struct mmc_data *data)
522 {
523 	struct sg_mapping_iter *miter = &host->miter;
524 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_RXFIFO;
525 	uint32_t *buf;
526 	uint32_t d;
527 	uint32_t status;
528 	size_t i, j;
529 	unsigned int timeout;
530 
531 	while (sg_miter_next(miter)) {
532 		buf = miter->addr;
533 		i = miter->length;
534 		j = i / 32;
535 		i = i & 0x1f;
536 		while (j) {
537 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_RXFIFO_RD_REQ);
538 			if (unlikely(timeout))
539 				goto poll_timeout;
540 
541 			buf[0] = readl(fifo_addr);
542 			buf[1] = readl(fifo_addr);
543 			buf[2] = readl(fifo_addr);
544 			buf[3] = readl(fifo_addr);
545 			buf[4] = readl(fifo_addr);
546 			buf[5] = readl(fifo_addr);
547 			buf[6] = readl(fifo_addr);
548 			buf[7] = readl(fifo_addr);
549 
550 			buf += 8;
551 			--j;
552 		}
553 
554 		if (unlikely(i)) {
555 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_RXFIFO_RD_REQ);
556 			if (unlikely(timeout))
557 				goto poll_timeout;
558 
559 			while (i >= 4) {
560 				*buf++ = readl(fifo_addr);
561 				i -= 4;
562 			}
563 			if (unlikely(i > 0)) {
564 				d = readl(fifo_addr);
565 				memcpy(buf, &d, i);
566 			}
567 		}
568 		data->bytes_xfered += miter->length;
569 
570 		/* This can go away once MIPS implements
571 		 * flush_kernel_dcache_page */
572 		flush_dcache_page(miter->page);
573 	}
574 	sg_miter_stop(miter);
575 
576 	/* For whatever reason there is sometime one word more in the fifo then
577 	 * requested */
578 	timeout = 1000;
579 	status = readl(host->base + JZ_REG_MMC_STATUS);
580 	while (!(status & JZ_MMC_STATUS_DATA_FIFO_EMPTY) && --timeout) {
581 		d = readl(fifo_addr);
582 		status = readl(host->base + JZ_REG_MMC_STATUS);
583 	}
584 
585 	return false;
586 
587 poll_timeout:
588 	miter->consumed = (void *)buf - miter->addr;
589 	data->bytes_xfered += miter->consumed;
590 	sg_miter_stop(miter);
591 
592 	return true;
593 }
594 
595 static void jz4740_mmc_timeout(struct timer_list *t)
596 {
597 	struct jz4740_mmc_host *host = from_timer(host, t, timeout_timer);
598 
599 	if (!test_and_clear_bit(0, &host->waiting))
600 		return;
601 
602 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_END_CMD_RES, false);
603 
604 	host->req->cmd->error = -ETIMEDOUT;
605 	jz4740_mmc_request_done(host);
606 }
607 
608 static void jz4740_mmc_read_response(struct jz4740_mmc_host *host,
609 	struct mmc_command *cmd)
610 {
611 	int i;
612 	uint16_t tmp;
613 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_RESP_FIFO;
614 
615 	if (cmd->flags & MMC_RSP_136) {
616 		tmp = readw(fifo_addr);
617 		for (i = 0; i < 4; ++i) {
618 			cmd->resp[i] = tmp << 24;
619 			tmp = readw(fifo_addr);
620 			cmd->resp[i] |= tmp << 8;
621 			tmp = readw(fifo_addr);
622 			cmd->resp[i] |= tmp >> 8;
623 		}
624 	} else {
625 		cmd->resp[0] = readw(fifo_addr) << 24;
626 		cmd->resp[0] |= readw(fifo_addr) << 8;
627 		cmd->resp[0] |= readw(fifo_addr) & 0xff;
628 	}
629 }
630 
631 static void jz4740_mmc_send_command(struct jz4740_mmc_host *host,
632 	struct mmc_command *cmd)
633 {
634 	uint32_t cmdat = host->cmdat;
635 
636 	host->cmdat &= ~JZ_MMC_CMDAT_INIT;
637 	jz4740_mmc_clock_disable(host);
638 
639 	host->cmd = cmd;
640 
641 	if (cmd->flags & MMC_RSP_BUSY)
642 		cmdat |= JZ_MMC_CMDAT_BUSY;
643 
644 	switch (mmc_resp_type(cmd)) {
645 	case MMC_RSP_R1B:
646 	case MMC_RSP_R1:
647 		cmdat |= JZ_MMC_CMDAT_RSP_R1;
648 		break;
649 	case MMC_RSP_R2:
650 		cmdat |= JZ_MMC_CMDAT_RSP_R2;
651 		break;
652 	case MMC_RSP_R3:
653 		cmdat |= JZ_MMC_CMDAT_RSP_R3;
654 		break;
655 	default:
656 		break;
657 	}
658 
659 	if (cmd->data) {
660 		cmdat |= JZ_MMC_CMDAT_DATA_EN;
661 		if (cmd->data->flags & MMC_DATA_WRITE)
662 			cmdat |= JZ_MMC_CMDAT_WRITE;
663 		if (host->use_dma) {
664 			/*
665 			 * The 4780's MMC controller has integrated DMA ability
666 			 * in addition to being able to use the external DMA
667 			 * controller. It moves DMA control bits to a separate
668 			 * register. The DMA_SEL bit chooses the external
669 			 * controller over the integrated one. Earlier SoCs
670 			 * can only use the external controller, and have a
671 			 * single DMA enable bit in CMDAT.
672 			 */
673 			if (host->version >= JZ_MMC_JZ4780) {
674 				writel(JZ_MMC_DMAC_DMA_EN | JZ_MMC_DMAC_DMA_SEL,
675 				       host->base + JZ_REG_MMC_DMAC);
676 			} else {
677 				cmdat |= JZ_MMC_CMDAT_DMA_EN;
678 			}
679 		} else if (host->version >= JZ_MMC_JZ4780) {
680 			writel(0, host->base + JZ_REG_MMC_DMAC);
681 		}
682 
683 		writew(cmd->data->blksz, host->base + JZ_REG_MMC_BLKLEN);
684 		writew(cmd->data->blocks, host->base + JZ_REG_MMC_NOB);
685 	}
686 
687 	writeb(cmd->opcode, host->base + JZ_REG_MMC_CMD);
688 	writel(cmd->arg, host->base + JZ_REG_MMC_ARG);
689 	writel(cmdat, host->base + JZ_REG_MMC_CMDAT);
690 
691 	jz4740_mmc_clock_enable(host, 1);
692 }
693 
694 static void jz_mmc_prepare_data_transfer(struct jz4740_mmc_host *host)
695 {
696 	struct mmc_command *cmd = host->req->cmd;
697 	struct mmc_data *data = cmd->data;
698 	int direction;
699 
700 	if (data->flags & MMC_DATA_READ)
701 		direction = SG_MITER_TO_SG;
702 	else
703 		direction = SG_MITER_FROM_SG;
704 
705 	sg_miter_start(&host->miter, data->sg, data->sg_len, direction);
706 }
707 
708 
709 static irqreturn_t jz_mmc_irq_worker(int irq, void *devid)
710 {
711 	struct jz4740_mmc_host *host = (struct jz4740_mmc_host *)devid;
712 	struct mmc_command *cmd = host->req->cmd;
713 	struct mmc_request *req = host->req;
714 	struct mmc_data *data = cmd->data;
715 	bool timeout = false;
716 
717 	if (cmd->error)
718 		host->state = JZ4740_MMC_STATE_DONE;
719 
720 	switch (host->state) {
721 	case JZ4740_MMC_STATE_READ_RESPONSE:
722 		if (cmd->flags & MMC_RSP_PRESENT)
723 			jz4740_mmc_read_response(host, cmd);
724 
725 		if (!data)
726 			break;
727 
728 		jz_mmc_prepare_data_transfer(host);
729 		/* fall through */
730 
731 	case JZ4740_MMC_STATE_TRANSFER_DATA:
732 		if (host->use_dma) {
733 			/* Use DMA if enabled.
734 			 * Data transfer direction is defined later by
735 			 * relying on data flags in
736 			 * jz4740_mmc_prepare_dma_data() and
737 			 * jz4740_mmc_start_dma_transfer().
738 			 */
739 			timeout = jz4740_mmc_start_dma_transfer(host, data);
740 			data->bytes_xfered = data->blocks * data->blksz;
741 		} else if (data->flags & MMC_DATA_READ)
742 			/* Use PIO if DMA is not enabled.
743 			 * Data transfer direction was defined before
744 			 * by relying on data flags in
745 			 * jz_mmc_prepare_data_transfer().
746 			 */
747 			timeout = jz4740_mmc_read_data(host, data);
748 		else
749 			timeout = jz4740_mmc_write_data(host, data);
750 
751 		if (unlikely(timeout)) {
752 			host->state = JZ4740_MMC_STATE_TRANSFER_DATA;
753 			break;
754 		}
755 
756 		jz4740_mmc_transfer_check_state(host, data);
757 
758 		timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_DATA_TRAN_DONE);
759 		if (unlikely(timeout)) {
760 			host->state = JZ4740_MMC_STATE_SEND_STOP;
761 			break;
762 		}
763 		jz4740_mmc_write_irq_reg(host, JZ_MMC_IRQ_DATA_TRAN_DONE);
764 		/* fall through */
765 
766 	case JZ4740_MMC_STATE_SEND_STOP:
767 		if (!req->stop)
768 			break;
769 
770 		jz4740_mmc_send_command(host, req->stop);
771 
772 		if (mmc_resp_type(req->stop) & MMC_RSP_BUSY) {
773 			timeout = jz4740_mmc_poll_irq(host,
774 						      JZ_MMC_IRQ_PRG_DONE);
775 			if (timeout) {
776 				host->state = JZ4740_MMC_STATE_DONE;
777 				break;
778 			}
779 		}
780 	case JZ4740_MMC_STATE_DONE:
781 		break;
782 	}
783 
784 	if (!timeout)
785 		jz4740_mmc_request_done(host);
786 
787 	return IRQ_HANDLED;
788 }
789 
790 static irqreturn_t jz_mmc_irq(int irq, void *devid)
791 {
792 	struct jz4740_mmc_host *host = devid;
793 	struct mmc_command *cmd = host->cmd;
794 	uint32_t irq_reg, status, tmp;
795 
796 	status = readl(host->base + JZ_REG_MMC_STATUS);
797 	irq_reg = jz4740_mmc_read_irq_reg(host);
798 
799 	tmp = irq_reg;
800 	irq_reg &= ~host->irq_mask;
801 
802 	tmp &= ~(JZ_MMC_IRQ_TXFIFO_WR_REQ | JZ_MMC_IRQ_RXFIFO_RD_REQ |
803 		JZ_MMC_IRQ_PRG_DONE | JZ_MMC_IRQ_DATA_TRAN_DONE);
804 
805 	if (tmp != irq_reg)
806 		jz4740_mmc_write_irq_reg(host, tmp & ~irq_reg);
807 
808 	if (irq_reg & JZ_MMC_IRQ_SDIO) {
809 		jz4740_mmc_write_irq_reg(host, JZ_MMC_IRQ_SDIO);
810 		mmc_signal_sdio_irq(host->mmc);
811 		irq_reg &= ~JZ_MMC_IRQ_SDIO;
812 	}
813 
814 	if (host->req && cmd && irq_reg) {
815 		if (test_and_clear_bit(0, &host->waiting)) {
816 			del_timer(&host->timeout_timer);
817 
818 			if (status & JZ_MMC_STATUS_TIMEOUT_RES) {
819 				cmd->error = -ETIMEDOUT;
820 			} else if (status & JZ_MMC_STATUS_CRC_RES_ERR) {
821 				cmd->error = -EIO;
822 			} else if (status & (JZ_MMC_STATUS_CRC_READ_ERROR |
823 				    JZ_MMC_STATUS_CRC_WRITE_ERROR)) {
824 				if (cmd->data)
825 					cmd->data->error = -EIO;
826 				cmd->error = -EIO;
827 			}
828 
829 			jz4740_mmc_set_irq_enabled(host, irq_reg, false);
830 			jz4740_mmc_write_irq_reg(host, irq_reg);
831 
832 			return IRQ_WAKE_THREAD;
833 		}
834 	}
835 
836 	return IRQ_HANDLED;
837 }
838 
839 static int jz4740_mmc_set_clock_rate(struct jz4740_mmc_host *host, int rate)
840 {
841 	int div = 0;
842 	int real_rate;
843 
844 	jz4740_mmc_clock_disable(host);
845 	clk_set_rate(host->clk, host->mmc->f_max);
846 
847 	real_rate = clk_get_rate(host->clk);
848 
849 	while (real_rate > rate && div < 7) {
850 		++div;
851 		real_rate >>= 1;
852 	}
853 
854 	writew(div, host->base + JZ_REG_MMC_CLKRT);
855 	return real_rate;
856 }
857 
858 static void jz4740_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
859 {
860 	struct jz4740_mmc_host *host = mmc_priv(mmc);
861 
862 	host->req = req;
863 
864 	jz4740_mmc_write_irq_reg(host, ~0);
865 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_END_CMD_RES, true);
866 
867 	host->state = JZ4740_MMC_STATE_READ_RESPONSE;
868 	set_bit(0, &host->waiting);
869 	mod_timer(&host->timeout_timer, jiffies + 5*HZ);
870 	jz4740_mmc_send_command(host, req->cmd);
871 }
872 
873 static void jz4740_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
874 {
875 	struct jz4740_mmc_host *host = mmc_priv(mmc);
876 	if (ios->clock)
877 		jz4740_mmc_set_clock_rate(host, ios->clock);
878 
879 	switch (ios->power_mode) {
880 	case MMC_POWER_UP:
881 		jz4740_mmc_reset(host);
882 		if (!IS_ERR(mmc->supply.vmmc))
883 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
884 		host->cmdat |= JZ_MMC_CMDAT_INIT;
885 		clk_prepare_enable(host->clk);
886 		break;
887 	case MMC_POWER_ON:
888 		break;
889 	default:
890 		if (!IS_ERR(mmc->supply.vmmc))
891 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
892 		clk_disable_unprepare(host->clk);
893 		break;
894 	}
895 
896 	switch (ios->bus_width) {
897 	case MMC_BUS_WIDTH_1:
898 		host->cmdat &= ~JZ_MMC_CMDAT_BUS_WIDTH_4BIT;
899 		break;
900 	case MMC_BUS_WIDTH_4:
901 		host->cmdat |= JZ_MMC_CMDAT_BUS_WIDTH_4BIT;
902 		break;
903 	default:
904 		break;
905 	}
906 }
907 
908 static void jz4740_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
909 {
910 	struct jz4740_mmc_host *host = mmc_priv(mmc);
911 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_SDIO, enable);
912 }
913 
914 static const struct mmc_host_ops jz4740_mmc_ops = {
915 	.request	= jz4740_mmc_request,
916 	.pre_req	= jz4740_mmc_pre_request,
917 	.post_req	= jz4740_mmc_post_request,
918 	.set_ios	= jz4740_mmc_set_ios,
919 	.get_ro		= mmc_gpio_get_ro,
920 	.get_cd		= mmc_gpio_get_cd,
921 	.enable_sdio_irq = jz4740_mmc_enable_sdio_irq,
922 };
923 
924 static const struct of_device_id jz4740_mmc_of_match[] = {
925 	{ .compatible = "ingenic,jz4740-mmc", .data = (void *) JZ_MMC_JZ4740 },
926 	{ .compatible = "ingenic,jz4725b-mmc", .data = (void *)JZ_MMC_JZ4725B },
927 	{ .compatible = "ingenic,jz4780-mmc", .data = (void *) JZ_MMC_JZ4780 },
928 	{},
929 };
930 MODULE_DEVICE_TABLE(of, jz4740_mmc_of_match);
931 
932 static int jz4740_mmc_probe(struct platform_device* pdev)
933 {
934 	int ret;
935 	struct mmc_host *mmc;
936 	struct jz4740_mmc_host *host;
937 	const struct of_device_id *match;
938 
939 	mmc = mmc_alloc_host(sizeof(struct jz4740_mmc_host), &pdev->dev);
940 	if (!mmc) {
941 		dev_err(&pdev->dev, "Failed to alloc mmc host structure\n");
942 		return -ENOMEM;
943 	}
944 
945 	host = mmc_priv(mmc);
946 
947 	match = of_match_device(jz4740_mmc_of_match, &pdev->dev);
948 	if (match) {
949 		host->version = (enum jz4740_mmc_version)match->data;
950 	} else {
951 		/* JZ4740 should be the only one using legacy probe */
952 		host->version = JZ_MMC_JZ4740;
953 	}
954 
955 	ret = mmc_of_parse(mmc);
956 	if (ret) {
957 		if (ret != -EPROBE_DEFER)
958 			dev_err(&pdev->dev,
959 				"could not parse device properties: %d\n", ret);
960 		goto err_free_host;
961 	}
962 
963 	mmc_regulator_get_supply(mmc);
964 
965 	host->irq = platform_get_irq(pdev, 0);
966 	if (host->irq < 0) {
967 		ret = host->irq;
968 		goto err_free_host;
969 	}
970 
971 	host->clk = devm_clk_get(&pdev->dev, "mmc");
972 	if (IS_ERR(host->clk)) {
973 		ret = PTR_ERR(host->clk);
974 		dev_err(&pdev->dev, "Failed to get mmc clock\n");
975 		goto err_free_host;
976 	}
977 
978 	host->mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
979 	host->base = devm_ioremap_resource(&pdev->dev, host->mem_res);
980 	if (IS_ERR(host->base)) {
981 		ret = PTR_ERR(host->base);
982 		dev_err(&pdev->dev, "Failed to ioremap base memory\n");
983 		goto err_free_host;
984 	}
985 
986 	mmc->ops = &jz4740_mmc_ops;
987 	if (!mmc->f_max)
988 		mmc->f_max = JZ_MMC_CLK_RATE;
989 	mmc->f_min = mmc->f_max / 128;
990 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
991 
992 	mmc->max_blk_size = (1 << 10) - 1;
993 	mmc->max_blk_count = (1 << 15) - 1;
994 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
995 
996 	mmc->max_segs = 128;
997 	mmc->max_seg_size = mmc->max_req_size;
998 
999 	host->mmc = mmc;
1000 	host->pdev = pdev;
1001 	spin_lock_init(&host->lock);
1002 	host->irq_mask = ~0;
1003 
1004 	jz4740_mmc_reset(host);
1005 
1006 	ret = request_threaded_irq(host->irq, jz_mmc_irq, jz_mmc_irq_worker, 0,
1007 			dev_name(&pdev->dev), host);
1008 	if (ret) {
1009 		dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
1010 		goto err_free_host;
1011 	}
1012 
1013 	jz4740_mmc_clock_disable(host);
1014 	timer_setup(&host->timeout_timer, jz4740_mmc_timeout, 0);
1015 
1016 	ret = jz4740_mmc_acquire_dma_channels(host);
1017 	if (ret == -EPROBE_DEFER)
1018 		goto err_free_irq;
1019 	host->use_dma = !ret;
1020 
1021 	platform_set_drvdata(pdev, host);
1022 	ret = mmc_add_host(mmc);
1023 
1024 	if (ret) {
1025 		dev_err(&pdev->dev, "Failed to add mmc host: %d\n", ret);
1026 		goto err_release_dma;
1027 	}
1028 	dev_info(&pdev->dev, "JZ SD/MMC card driver registered\n");
1029 
1030 	dev_info(&pdev->dev, "Using %s, %d-bit mode\n",
1031 		 host->use_dma ? "DMA" : "PIO",
1032 		 (mmc->caps & MMC_CAP_4_BIT_DATA) ? 4 : 1);
1033 
1034 	return 0;
1035 
1036 err_release_dma:
1037 	if (host->use_dma)
1038 		jz4740_mmc_release_dma_channels(host);
1039 err_free_irq:
1040 	free_irq(host->irq, host);
1041 err_free_host:
1042 	mmc_free_host(mmc);
1043 
1044 	return ret;
1045 }
1046 
1047 static int jz4740_mmc_remove(struct platform_device *pdev)
1048 {
1049 	struct jz4740_mmc_host *host = platform_get_drvdata(pdev);
1050 
1051 	del_timer_sync(&host->timeout_timer);
1052 	jz4740_mmc_set_irq_enabled(host, 0xff, false);
1053 	jz4740_mmc_reset(host);
1054 
1055 	mmc_remove_host(host->mmc);
1056 
1057 	free_irq(host->irq, host);
1058 
1059 	if (host->use_dma)
1060 		jz4740_mmc_release_dma_channels(host);
1061 
1062 	mmc_free_host(host->mmc);
1063 
1064 	return 0;
1065 }
1066 
1067 #ifdef CONFIG_PM_SLEEP
1068 
1069 static int jz4740_mmc_suspend(struct device *dev)
1070 {
1071 	return pinctrl_pm_select_sleep_state(dev);
1072 }
1073 
1074 static int jz4740_mmc_resume(struct device *dev)
1075 {
1076 	return pinctrl_pm_select_default_state(dev);
1077 }
1078 
1079 static SIMPLE_DEV_PM_OPS(jz4740_mmc_pm_ops, jz4740_mmc_suspend,
1080 	jz4740_mmc_resume);
1081 #define JZ4740_MMC_PM_OPS (&jz4740_mmc_pm_ops)
1082 #else
1083 #define JZ4740_MMC_PM_OPS NULL
1084 #endif
1085 
1086 static struct platform_driver jz4740_mmc_driver = {
1087 	.probe = jz4740_mmc_probe,
1088 	.remove = jz4740_mmc_remove,
1089 	.driver = {
1090 		.name = "jz4740-mmc",
1091 		.of_match_table = of_match_ptr(jz4740_mmc_of_match),
1092 		.pm = JZ4740_MMC_PM_OPS,
1093 	},
1094 };
1095 
1096 module_platform_driver(jz4740_mmc_driver);
1097 
1098 MODULE_DESCRIPTION("JZ4740 SD/MMC controller driver");
1099 MODULE_LICENSE("GPL");
1100 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
1101