xref: /openbmc/linux/drivers/mmc/host/jz4740_mmc.c (revision 8931ddd8)
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_LPM		0x40
45 #define JZ_REG_MMC_DMAC		0x44
46 
47 #define JZ_MMC_STRPCL_EXIT_MULTIPLE BIT(7)
48 #define JZ_MMC_STRPCL_EXIT_TRANSFER BIT(6)
49 #define JZ_MMC_STRPCL_START_READWAIT BIT(5)
50 #define JZ_MMC_STRPCL_STOP_READWAIT BIT(4)
51 #define JZ_MMC_STRPCL_RESET BIT(3)
52 #define JZ_MMC_STRPCL_START_OP BIT(2)
53 #define JZ_MMC_STRPCL_CLOCK_CONTROL (BIT(1) | BIT(0))
54 #define JZ_MMC_STRPCL_CLOCK_STOP BIT(0)
55 #define JZ_MMC_STRPCL_CLOCK_START BIT(1)
56 
57 
58 #define JZ_MMC_STATUS_IS_RESETTING BIT(15)
59 #define JZ_MMC_STATUS_SDIO_INT_ACTIVE BIT(14)
60 #define JZ_MMC_STATUS_PRG_DONE BIT(13)
61 #define JZ_MMC_STATUS_DATA_TRAN_DONE BIT(12)
62 #define JZ_MMC_STATUS_END_CMD_RES BIT(11)
63 #define JZ_MMC_STATUS_DATA_FIFO_AFULL BIT(10)
64 #define JZ_MMC_STATUS_IS_READWAIT BIT(9)
65 #define JZ_MMC_STATUS_CLK_EN BIT(8)
66 #define JZ_MMC_STATUS_DATA_FIFO_FULL BIT(7)
67 #define JZ_MMC_STATUS_DATA_FIFO_EMPTY BIT(6)
68 #define JZ_MMC_STATUS_CRC_RES_ERR BIT(5)
69 #define JZ_MMC_STATUS_CRC_READ_ERROR BIT(4)
70 #define JZ_MMC_STATUS_TIMEOUT_WRITE BIT(3)
71 #define JZ_MMC_STATUS_CRC_WRITE_ERROR BIT(2)
72 #define JZ_MMC_STATUS_TIMEOUT_RES BIT(1)
73 #define JZ_MMC_STATUS_TIMEOUT_READ BIT(0)
74 
75 #define JZ_MMC_STATUS_READ_ERROR_MASK (BIT(4) | BIT(0))
76 #define JZ_MMC_STATUS_WRITE_ERROR_MASK (BIT(3) | BIT(2))
77 
78 
79 #define JZ_MMC_CMDAT_IO_ABORT BIT(11)
80 #define JZ_MMC_CMDAT_BUS_WIDTH_4BIT BIT(10)
81 #define JZ_MMC_CMDAT_BUS_WIDTH_8BIT (BIT(10) | BIT(9))
82 #define	JZ_MMC_CMDAT_BUS_WIDTH_MASK (BIT(10) | BIT(9))
83 #define JZ_MMC_CMDAT_DMA_EN BIT(8)
84 #define JZ_MMC_CMDAT_INIT BIT(7)
85 #define JZ_MMC_CMDAT_BUSY BIT(6)
86 #define JZ_MMC_CMDAT_STREAM BIT(5)
87 #define JZ_MMC_CMDAT_WRITE BIT(4)
88 #define JZ_MMC_CMDAT_DATA_EN BIT(3)
89 #define JZ_MMC_CMDAT_RESPONSE_FORMAT (BIT(2) | BIT(1) | BIT(0))
90 #define JZ_MMC_CMDAT_RSP_R1 1
91 #define JZ_MMC_CMDAT_RSP_R2 2
92 #define JZ_MMC_CMDAT_RSP_R3 3
93 
94 #define JZ_MMC_IRQ_SDIO BIT(7)
95 #define JZ_MMC_IRQ_TXFIFO_WR_REQ BIT(6)
96 #define JZ_MMC_IRQ_RXFIFO_RD_REQ BIT(5)
97 #define JZ_MMC_IRQ_END_CMD_RES BIT(2)
98 #define JZ_MMC_IRQ_PRG_DONE BIT(1)
99 #define JZ_MMC_IRQ_DATA_TRAN_DONE BIT(0)
100 
101 #define JZ_MMC_DMAC_DMA_SEL BIT(1)
102 #define JZ_MMC_DMAC_DMA_EN BIT(0)
103 
104 #define	JZ_MMC_LPM_DRV_RISING BIT(31)
105 #define	JZ_MMC_LPM_DRV_RISING_QTR_PHASE_DLY BIT(31)
106 #define	JZ_MMC_LPM_DRV_RISING_1NS_DLY BIT(30)
107 #define	JZ_MMC_LPM_SMP_RISING_QTR_OR_HALF_PHASE_DLY BIT(29)
108 #define	JZ_MMC_LPM_LOW_POWER_MODE_EN BIT(0)
109 
110 #define JZ_MMC_CLK_RATE 24000000
111 #define JZ_MMC_REQ_TIMEOUT_MS 5000
112 
113 enum jz4740_mmc_version {
114 	JZ_MMC_JZ4740,
115 	JZ_MMC_JZ4725B,
116 	JZ_MMC_JZ4760,
117 	JZ_MMC_JZ4780,
118 	JZ_MMC_X1000,
119 };
120 
121 enum jz4740_mmc_state {
122 	JZ4740_MMC_STATE_READ_RESPONSE,
123 	JZ4740_MMC_STATE_TRANSFER_DATA,
124 	JZ4740_MMC_STATE_SEND_STOP,
125 	JZ4740_MMC_STATE_DONE,
126 };
127 
128 /*
129  * The MMC core allows to prepare a mmc_request while another mmc_request
130  * is in-flight. This is used via the pre_req/post_req hooks.
131  * This driver uses the pre_req/post_req hooks to map/unmap the mmc_request.
132  * Following what other drivers do (sdhci, dw_mmc) we use the following cookie
133  * flags to keep track of the mmc_request mapping state.
134  *
135  * COOKIE_UNMAPPED: the request is not mapped.
136  * COOKIE_PREMAPPED: the request was mapped in pre_req,
137  * and should be unmapped in post_req.
138  * COOKIE_MAPPED: the request was mapped in the irq handler,
139  * and should be unmapped before mmc_request_done is called..
140  */
141 enum jz4780_cookie {
142 	COOKIE_UNMAPPED = 0,
143 	COOKIE_PREMAPPED,
144 	COOKIE_MAPPED,
145 };
146 
147 struct jz4740_mmc_host {
148 	struct mmc_host *mmc;
149 	struct platform_device *pdev;
150 	struct clk *clk;
151 
152 	enum jz4740_mmc_version version;
153 
154 	int 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 		writel(val, host->base + JZ_REG_MMC_IREG);
199 	else
200 		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 	if (host->dma_rx)
221 		dma_release_channel(host->dma_rx);
222 }
223 
224 static int jz4740_mmc_acquire_dma_channels(struct jz4740_mmc_host *host)
225 {
226 	struct device *dev = mmc_dev(host->mmc);
227 
228 	host->dma_tx = dma_request_chan(dev, "tx-rx");
229 	if (!IS_ERR(host->dma_tx))
230 		return 0;
231 
232 	if (PTR_ERR(host->dma_tx) != -ENODEV) {
233 		dev_err(dev, "Failed to get dma tx-rx channel\n");
234 		return PTR_ERR(host->dma_tx);
235 	}
236 
237 	host->dma_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
238 	if (IS_ERR(host->dma_tx)) {
239 		dev_err(mmc_dev(host->mmc), "Failed to get dma_tx channel\n");
240 		return PTR_ERR(host->dma_tx);
241 	}
242 
243 	host->dma_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
244 	if (IS_ERR(host->dma_rx)) {
245 		dev_err(mmc_dev(host->mmc), "Failed to get dma_rx channel\n");
246 		dma_release_channel(host->dma_tx);
247 		return PTR_ERR(host->dma_rx);
248 	}
249 
250 	return 0;
251 }
252 
253 static inline struct dma_chan *jz4740_mmc_get_dma_chan(struct jz4740_mmc_host *host,
254 						       struct mmc_data *data)
255 {
256 	if ((data->flags & MMC_DATA_READ) && host->dma_rx)
257 		return host->dma_rx;
258 	else
259 		return host->dma_tx;
260 }
261 
262 static void jz4740_mmc_dma_unmap(struct jz4740_mmc_host *host,
263 				 struct mmc_data *data)
264 {
265 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
266 	enum dma_data_direction dir = mmc_get_dma_dir(data);
267 
268 	dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, dir);
269 	data->host_cookie = COOKIE_UNMAPPED;
270 }
271 
272 /* Prepares DMA data for current or next transfer.
273  * A request can be in-flight when this is called.
274  */
275 static int jz4740_mmc_prepare_dma_data(struct jz4740_mmc_host *host,
276 				       struct mmc_data *data,
277 				       int cookie)
278 {
279 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
280 	enum dma_data_direction dir = mmc_get_dma_dir(data);
281 	int sg_count;
282 
283 	if (data->host_cookie == COOKIE_PREMAPPED)
284 		return data->sg_count;
285 
286 	sg_count = dma_map_sg(chan->device->dev,
287 			data->sg,
288 			data->sg_len,
289 			dir);
290 
291 	if (sg_count <= 0) {
292 		dev_err(mmc_dev(host->mmc),
293 			"Failed to map scatterlist for DMA operation\n");
294 		return -EINVAL;
295 	}
296 
297 	data->sg_count = sg_count;
298 	data->host_cookie = cookie;
299 
300 	return data->sg_count;
301 }
302 
303 static int jz4740_mmc_start_dma_transfer(struct jz4740_mmc_host *host,
304 					 struct mmc_data *data)
305 {
306 	struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
307 	struct dma_async_tx_descriptor *desc;
308 	struct dma_slave_config conf = {
309 		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
310 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
311 		.src_maxburst = JZ4740_MMC_FIFO_HALF_SIZE,
312 		.dst_maxburst = JZ4740_MMC_FIFO_HALF_SIZE,
313 	};
314 	int sg_count;
315 
316 	if (data->flags & MMC_DATA_WRITE) {
317 		conf.direction = DMA_MEM_TO_DEV;
318 		conf.dst_addr = host->mem_res->start + JZ_REG_MMC_TXFIFO;
319 	} else {
320 		conf.direction = DMA_DEV_TO_MEM;
321 		conf.src_addr = host->mem_res->start + JZ_REG_MMC_RXFIFO;
322 	}
323 
324 	sg_count = jz4740_mmc_prepare_dma_data(host, data, COOKIE_MAPPED);
325 	if (sg_count < 0)
326 		return sg_count;
327 
328 	dmaengine_slave_config(chan, &conf);
329 	desc = dmaengine_prep_slave_sg(chan, data->sg, sg_count,
330 			conf.direction,
331 			DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
332 	if (!desc) {
333 		dev_err(mmc_dev(host->mmc),
334 			"Failed to allocate DMA %s descriptor",
335 			 conf.direction == DMA_MEM_TO_DEV ? "TX" : "RX");
336 		goto dma_unmap;
337 	}
338 
339 	dmaengine_submit(desc);
340 	dma_async_issue_pending(chan);
341 
342 	return 0;
343 
344 dma_unmap:
345 	if (data->host_cookie == COOKIE_MAPPED)
346 		jz4740_mmc_dma_unmap(host, data);
347 	return -ENOMEM;
348 }
349 
350 static void jz4740_mmc_pre_request(struct mmc_host *mmc,
351 				   struct mmc_request *mrq)
352 {
353 	struct jz4740_mmc_host *host = mmc_priv(mmc);
354 	struct mmc_data *data = mrq->data;
355 
356 	if (!host->use_dma)
357 		return;
358 
359 	data->host_cookie = COOKIE_UNMAPPED;
360 	if (jz4740_mmc_prepare_dma_data(host, data, COOKIE_PREMAPPED) < 0)
361 		data->host_cookie = COOKIE_UNMAPPED;
362 }
363 
364 static void jz4740_mmc_post_request(struct mmc_host *mmc,
365 				    struct mmc_request *mrq,
366 				    int err)
367 {
368 	struct jz4740_mmc_host *host = mmc_priv(mmc);
369 	struct mmc_data *data = mrq->data;
370 
371 	if (data && data->host_cookie != COOKIE_UNMAPPED)
372 		jz4740_mmc_dma_unmap(host, data);
373 
374 	if (err) {
375 		struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
376 
377 		dmaengine_terminate_all(chan);
378 	}
379 }
380 
381 /*----------------------------------------------------------------------------*/
382 
383 static void jz4740_mmc_set_irq_enabled(struct jz4740_mmc_host *host,
384 	unsigned int irq, bool enabled)
385 {
386 	unsigned long flags;
387 
388 	spin_lock_irqsave(&host->lock, flags);
389 	if (enabled)
390 		host->irq_mask &= ~irq;
391 	else
392 		host->irq_mask |= irq;
393 
394 	jz4740_mmc_write_irq_mask(host, host->irq_mask);
395 	spin_unlock_irqrestore(&host->lock, flags);
396 }
397 
398 static void jz4740_mmc_clock_enable(struct jz4740_mmc_host *host,
399 	bool start_transfer)
400 {
401 	uint16_t val = JZ_MMC_STRPCL_CLOCK_START;
402 
403 	if (start_transfer)
404 		val |= JZ_MMC_STRPCL_START_OP;
405 
406 	writew(val, host->base + JZ_REG_MMC_STRPCL);
407 }
408 
409 static void jz4740_mmc_clock_disable(struct jz4740_mmc_host *host)
410 {
411 	uint32_t status;
412 	unsigned int timeout = 1000;
413 
414 	writew(JZ_MMC_STRPCL_CLOCK_STOP, host->base + JZ_REG_MMC_STRPCL);
415 	do {
416 		status = readl(host->base + JZ_REG_MMC_STATUS);
417 	} while (status & JZ_MMC_STATUS_CLK_EN && --timeout);
418 }
419 
420 static void jz4740_mmc_reset(struct jz4740_mmc_host *host)
421 {
422 	uint32_t status;
423 	unsigned int timeout = 1000;
424 
425 	writew(JZ_MMC_STRPCL_RESET, host->base + JZ_REG_MMC_STRPCL);
426 	udelay(10);
427 	do {
428 		status = readl(host->base + JZ_REG_MMC_STATUS);
429 	} while (status & JZ_MMC_STATUS_IS_RESETTING && --timeout);
430 }
431 
432 static void jz4740_mmc_request_done(struct jz4740_mmc_host *host)
433 {
434 	struct mmc_request *req;
435 	struct mmc_data *data;
436 
437 	req = host->req;
438 	data = req->data;
439 	host->req = NULL;
440 
441 	if (data && data->host_cookie == COOKIE_MAPPED)
442 		jz4740_mmc_dma_unmap(host, data);
443 	mmc_request_done(host->mmc, req);
444 }
445 
446 static unsigned int jz4740_mmc_poll_irq(struct jz4740_mmc_host *host,
447 	unsigned int irq)
448 {
449 	unsigned int timeout = 0x800;
450 	uint32_t status;
451 
452 	do {
453 		status = jz4740_mmc_read_irq_reg(host);
454 	} while (!(status & irq) && --timeout);
455 
456 	if (timeout == 0) {
457 		set_bit(0, &host->waiting);
458 		mod_timer(&host->timeout_timer,
459 			  jiffies + msecs_to_jiffies(JZ_MMC_REQ_TIMEOUT_MS));
460 		jz4740_mmc_set_irq_enabled(host, irq, true);
461 		return true;
462 	}
463 
464 	return false;
465 }
466 
467 static void jz4740_mmc_transfer_check_state(struct jz4740_mmc_host *host,
468 	struct mmc_data *data)
469 {
470 	int status;
471 
472 	status = readl(host->base + JZ_REG_MMC_STATUS);
473 	if (status & JZ_MMC_STATUS_WRITE_ERROR_MASK) {
474 		if (status & (JZ_MMC_STATUS_TIMEOUT_WRITE)) {
475 			host->req->cmd->error = -ETIMEDOUT;
476 			data->error = -ETIMEDOUT;
477 		} else {
478 			host->req->cmd->error = -EIO;
479 			data->error = -EIO;
480 		}
481 	} else if (status & JZ_MMC_STATUS_READ_ERROR_MASK) {
482 		if (status & (JZ_MMC_STATUS_TIMEOUT_READ)) {
483 			host->req->cmd->error = -ETIMEDOUT;
484 			data->error = -ETIMEDOUT;
485 		} else {
486 			host->req->cmd->error = -EIO;
487 			data->error = -EIO;
488 		}
489 	}
490 }
491 
492 static bool jz4740_mmc_write_data(struct jz4740_mmc_host *host,
493 	struct mmc_data *data)
494 {
495 	struct sg_mapping_iter *miter = &host->miter;
496 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_TXFIFO;
497 	uint32_t *buf;
498 	bool timeout;
499 	size_t i, j;
500 
501 	while (sg_miter_next(miter)) {
502 		buf = miter->addr;
503 		i = miter->length / 4;
504 		j = i / 8;
505 		i = i & 0x7;
506 		while (j) {
507 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_TXFIFO_WR_REQ);
508 			if (unlikely(timeout))
509 				goto poll_timeout;
510 
511 			writel(buf[0], fifo_addr);
512 			writel(buf[1], fifo_addr);
513 			writel(buf[2], fifo_addr);
514 			writel(buf[3], fifo_addr);
515 			writel(buf[4], fifo_addr);
516 			writel(buf[5], fifo_addr);
517 			writel(buf[6], fifo_addr);
518 			writel(buf[7], fifo_addr);
519 			buf += 8;
520 			--j;
521 		}
522 		if (unlikely(i)) {
523 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_TXFIFO_WR_REQ);
524 			if (unlikely(timeout))
525 				goto poll_timeout;
526 
527 			while (i) {
528 				writel(*buf, fifo_addr);
529 				++buf;
530 				--i;
531 			}
532 		}
533 		data->bytes_xfered += miter->length;
534 	}
535 	sg_miter_stop(miter);
536 
537 	return false;
538 
539 poll_timeout:
540 	miter->consumed = (void *)buf - miter->addr;
541 	data->bytes_xfered += miter->consumed;
542 	sg_miter_stop(miter);
543 
544 	return true;
545 }
546 
547 static bool jz4740_mmc_read_data(struct jz4740_mmc_host *host,
548 				struct mmc_data *data)
549 {
550 	struct sg_mapping_iter *miter = &host->miter;
551 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_RXFIFO;
552 	uint32_t *buf;
553 	uint32_t d;
554 	uint32_t status;
555 	size_t i, j;
556 	unsigned int timeout;
557 
558 	while (sg_miter_next(miter)) {
559 		buf = miter->addr;
560 		i = miter->length;
561 		j = i / 32;
562 		i = i & 0x1f;
563 		while (j) {
564 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_RXFIFO_RD_REQ);
565 			if (unlikely(timeout))
566 				goto poll_timeout;
567 
568 			buf[0] = readl(fifo_addr);
569 			buf[1] = readl(fifo_addr);
570 			buf[2] = readl(fifo_addr);
571 			buf[3] = readl(fifo_addr);
572 			buf[4] = readl(fifo_addr);
573 			buf[5] = readl(fifo_addr);
574 			buf[6] = readl(fifo_addr);
575 			buf[7] = readl(fifo_addr);
576 
577 			buf += 8;
578 			--j;
579 		}
580 
581 		if (unlikely(i)) {
582 			timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_RXFIFO_RD_REQ);
583 			if (unlikely(timeout))
584 				goto poll_timeout;
585 
586 			while (i >= 4) {
587 				*buf++ = readl(fifo_addr);
588 				i -= 4;
589 			}
590 			if (unlikely(i > 0)) {
591 				d = readl(fifo_addr);
592 				memcpy(buf, &d, i);
593 			}
594 		}
595 		data->bytes_xfered += miter->length;
596 	}
597 	sg_miter_stop(miter);
598 
599 	/* For whatever reason there is sometime one word more in the fifo then
600 	 * requested */
601 	timeout = 1000;
602 	status = readl(host->base + JZ_REG_MMC_STATUS);
603 	while (!(status & JZ_MMC_STATUS_DATA_FIFO_EMPTY) && --timeout) {
604 		d = readl(fifo_addr);
605 		status = readl(host->base + JZ_REG_MMC_STATUS);
606 	}
607 
608 	return false;
609 
610 poll_timeout:
611 	miter->consumed = (void *)buf - miter->addr;
612 	data->bytes_xfered += miter->consumed;
613 	sg_miter_stop(miter);
614 
615 	return true;
616 }
617 
618 static void jz4740_mmc_timeout(struct timer_list *t)
619 {
620 	struct jz4740_mmc_host *host = from_timer(host, t, timeout_timer);
621 
622 	if (!test_and_clear_bit(0, &host->waiting))
623 		return;
624 
625 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_END_CMD_RES, false);
626 
627 	host->req->cmd->error = -ETIMEDOUT;
628 	jz4740_mmc_request_done(host);
629 }
630 
631 static void jz4740_mmc_read_response(struct jz4740_mmc_host *host,
632 	struct mmc_command *cmd)
633 {
634 	int i;
635 	uint16_t tmp;
636 	void __iomem *fifo_addr = host->base + JZ_REG_MMC_RESP_FIFO;
637 
638 	if (cmd->flags & MMC_RSP_136) {
639 		tmp = readw(fifo_addr);
640 		for (i = 0; i < 4; ++i) {
641 			cmd->resp[i] = tmp << 24;
642 			tmp = readw(fifo_addr);
643 			cmd->resp[i] |= tmp << 8;
644 			tmp = readw(fifo_addr);
645 			cmd->resp[i] |= tmp >> 8;
646 		}
647 	} else {
648 		cmd->resp[0] = readw(fifo_addr) << 24;
649 		cmd->resp[0] |= readw(fifo_addr) << 8;
650 		cmd->resp[0] |= readw(fifo_addr) & 0xff;
651 	}
652 }
653 
654 static void jz4740_mmc_send_command(struct jz4740_mmc_host *host,
655 	struct mmc_command *cmd)
656 {
657 	uint32_t cmdat = host->cmdat;
658 
659 	host->cmdat &= ~JZ_MMC_CMDAT_INIT;
660 	jz4740_mmc_clock_disable(host);
661 
662 	host->cmd = cmd;
663 
664 	if (cmd->flags & MMC_RSP_BUSY)
665 		cmdat |= JZ_MMC_CMDAT_BUSY;
666 
667 	switch (mmc_resp_type(cmd)) {
668 	case MMC_RSP_R1B:
669 	case MMC_RSP_R1:
670 		cmdat |= JZ_MMC_CMDAT_RSP_R1;
671 		break;
672 	case MMC_RSP_R2:
673 		cmdat |= JZ_MMC_CMDAT_RSP_R2;
674 		break;
675 	case MMC_RSP_R3:
676 		cmdat |= JZ_MMC_CMDAT_RSP_R3;
677 		break;
678 	default:
679 		break;
680 	}
681 
682 	if (cmd->data) {
683 		cmdat |= JZ_MMC_CMDAT_DATA_EN;
684 		if (cmd->data->flags & MMC_DATA_WRITE)
685 			cmdat |= JZ_MMC_CMDAT_WRITE;
686 		if (host->use_dma) {
687 			/*
688 			 * The JZ4780's MMC controller has integrated DMA ability
689 			 * in addition to being able to use the external DMA
690 			 * controller. It moves DMA control bits to a separate
691 			 * register. The DMA_SEL bit chooses the external
692 			 * controller over the integrated one. Earlier SoCs
693 			 * can only use the external controller, and have a
694 			 * single DMA enable bit in CMDAT.
695 			 */
696 			if (host->version >= JZ_MMC_JZ4780) {
697 				writel(JZ_MMC_DMAC_DMA_EN | JZ_MMC_DMAC_DMA_SEL,
698 				       host->base + JZ_REG_MMC_DMAC);
699 			} else {
700 				cmdat |= JZ_MMC_CMDAT_DMA_EN;
701 			}
702 		} else if (host->version >= JZ_MMC_JZ4780) {
703 			writel(0, host->base + JZ_REG_MMC_DMAC);
704 		}
705 
706 		writew(cmd->data->blksz, host->base + JZ_REG_MMC_BLKLEN);
707 		writew(cmd->data->blocks, host->base + JZ_REG_MMC_NOB);
708 	}
709 
710 	writeb(cmd->opcode, host->base + JZ_REG_MMC_CMD);
711 	writel(cmd->arg, host->base + JZ_REG_MMC_ARG);
712 	writel(cmdat, host->base + JZ_REG_MMC_CMDAT);
713 
714 	jz4740_mmc_clock_enable(host, 1);
715 }
716 
717 static void jz_mmc_prepare_data_transfer(struct jz4740_mmc_host *host)
718 {
719 	struct mmc_command *cmd = host->req->cmd;
720 	struct mmc_data *data = cmd->data;
721 	int direction;
722 
723 	if (data->flags & MMC_DATA_READ)
724 		direction = SG_MITER_TO_SG;
725 	else
726 		direction = SG_MITER_FROM_SG;
727 
728 	sg_miter_start(&host->miter, data->sg, data->sg_len, direction);
729 }
730 
731 
732 static irqreturn_t jz_mmc_irq_worker(int irq, void *devid)
733 {
734 	struct jz4740_mmc_host *host = (struct jz4740_mmc_host *)devid;
735 	struct mmc_command *cmd = host->req->cmd;
736 	struct mmc_request *req = host->req;
737 	struct mmc_data *data = cmd->data;
738 	bool timeout = false;
739 
740 	if (cmd->error)
741 		host->state = JZ4740_MMC_STATE_DONE;
742 
743 	switch (host->state) {
744 	case JZ4740_MMC_STATE_READ_RESPONSE:
745 		if (cmd->flags & MMC_RSP_PRESENT)
746 			jz4740_mmc_read_response(host, cmd);
747 
748 		if (!data)
749 			break;
750 
751 		jz_mmc_prepare_data_transfer(host);
752 		fallthrough;
753 
754 	case JZ4740_MMC_STATE_TRANSFER_DATA:
755 		if (host->use_dma) {
756 			/* Use DMA if enabled.
757 			 * Data transfer direction is defined later by
758 			 * relying on data flags in
759 			 * jz4740_mmc_prepare_dma_data() and
760 			 * jz4740_mmc_start_dma_transfer().
761 			 */
762 			timeout = jz4740_mmc_start_dma_transfer(host, data);
763 			data->bytes_xfered = data->blocks * data->blksz;
764 		} else if (data->flags & MMC_DATA_READ)
765 			/* Use PIO if DMA is not enabled.
766 			 * Data transfer direction was defined before
767 			 * by relying on data flags in
768 			 * jz_mmc_prepare_data_transfer().
769 			 */
770 			timeout = jz4740_mmc_read_data(host, data);
771 		else
772 			timeout = jz4740_mmc_write_data(host, data);
773 
774 		if (unlikely(timeout)) {
775 			host->state = JZ4740_MMC_STATE_TRANSFER_DATA;
776 			break;
777 		}
778 
779 		jz4740_mmc_transfer_check_state(host, data);
780 
781 		timeout = jz4740_mmc_poll_irq(host, JZ_MMC_IRQ_DATA_TRAN_DONE);
782 		if (unlikely(timeout)) {
783 			host->state = JZ4740_MMC_STATE_SEND_STOP;
784 			break;
785 		}
786 		jz4740_mmc_write_irq_reg(host, JZ_MMC_IRQ_DATA_TRAN_DONE);
787 		fallthrough;
788 
789 	case JZ4740_MMC_STATE_SEND_STOP:
790 		if (!req->stop)
791 			break;
792 
793 		jz4740_mmc_send_command(host, req->stop);
794 
795 		if (mmc_resp_type(req->stop) & MMC_RSP_BUSY) {
796 			timeout = jz4740_mmc_poll_irq(host,
797 						      JZ_MMC_IRQ_PRG_DONE);
798 			if (timeout) {
799 				host->state = JZ4740_MMC_STATE_DONE;
800 				break;
801 			}
802 		}
803 		fallthrough;
804 
805 	case JZ4740_MMC_STATE_DONE:
806 		break;
807 	}
808 
809 	if (!timeout)
810 		jz4740_mmc_request_done(host);
811 
812 	return IRQ_HANDLED;
813 }
814 
815 static irqreturn_t jz_mmc_irq(int irq, void *devid)
816 {
817 	struct jz4740_mmc_host *host = devid;
818 	struct mmc_command *cmd = host->cmd;
819 	uint32_t irq_reg, status, tmp;
820 
821 	status = readl(host->base + JZ_REG_MMC_STATUS);
822 	irq_reg = jz4740_mmc_read_irq_reg(host);
823 
824 	tmp = irq_reg;
825 	irq_reg &= ~host->irq_mask;
826 
827 	tmp &= ~(JZ_MMC_IRQ_TXFIFO_WR_REQ | JZ_MMC_IRQ_RXFIFO_RD_REQ |
828 		JZ_MMC_IRQ_PRG_DONE | JZ_MMC_IRQ_DATA_TRAN_DONE);
829 
830 	if (tmp != irq_reg)
831 		jz4740_mmc_write_irq_reg(host, tmp & ~irq_reg);
832 
833 	if (irq_reg & JZ_MMC_IRQ_SDIO) {
834 		jz4740_mmc_write_irq_reg(host, JZ_MMC_IRQ_SDIO);
835 		mmc_signal_sdio_irq(host->mmc);
836 		irq_reg &= ~JZ_MMC_IRQ_SDIO;
837 	}
838 
839 	if (host->req && cmd && irq_reg) {
840 		if (test_and_clear_bit(0, &host->waiting)) {
841 			del_timer(&host->timeout_timer);
842 
843 			if (status & JZ_MMC_STATUS_TIMEOUT_RES) {
844 				cmd->error = -ETIMEDOUT;
845 			} else if (status & JZ_MMC_STATUS_CRC_RES_ERR) {
846 				cmd->error = -EIO;
847 			} else if (status & (JZ_MMC_STATUS_CRC_READ_ERROR |
848 				    JZ_MMC_STATUS_CRC_WRITE_ERROR)) {
849 				if (cmd->data)
850 					cmd->data->error = -EIO;
851 				cmd->error = -EIO;
852 			}
853 
854 			jz4740_mmc_set_irq_enabled(host, irq_reg, false);
855 			jz4740_mmc_write_irq_reg(host, irq_reg);
856 
857 			return IRQ_WAKE_THREAD;
858 		}
859 	}
860 
861 	return IRQ_HANDLED;
862 }
863 
864 static int jz4740_mmc_set_clock_rate(struct jz4740_mmc_host *host, int rate)
865 {
866 	int div = 0;
867 	int real_rate;
868 
869 	jz4740_mmc_clock_disable(host);
870 	clk_set_rate(host->clk, host->mmc->f_max);
871 
872 	real_rate = clk_get_rate(host->clk);
873 
874 	while (real_rate > rate && div < 7) {
875 		++div;
876 		real_rate >>= 1;
877 	}
878 
879 	writew(div, host->base + JZ_REG_MMC_CLKRT);
880 
881 	if (real_rate > 25000000) {
882 		if (host->version >= JZ_MMC_JZ4780) {
883 			writel(JZ_MMC_LPM_DRV_RISING_QTR_PHASE_DLY |
884 				   JZ_MMC_LPM_SMP_RISING_QTR_OR_HALF_PHASE_DLY |
885 				   JZ_MMC_LPM_LOW_POWER_MODE_EN,
886 				   host->base + JZ_REG_MMC_LPM);
887 		} else if (host->version >= JZ_MMC_JZ4760) {
888 			writel(JZ_MMC_LPM_DRV_RISING |
889 				   JZ_MMC_LPM_LOW_POWER_MODE_EN,
890 				   host->base + JZ_REG_MMC_LPM);
891 		} else if (host->version >= JZ_MMC_JZ4725B)
892 			writel(JZ_MMC_LPM_LOW_POWER_MODE_EN,
893 				   host->base + JZ_REG_MMC_LPM);
894 	}
895 
896 	return real_rate;
897 }
898 
899 static void jz4740_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
900 {
901 	struct jz4740_mmc_host *host = mmc_priv(mmc);
902 
903 	host->req = req;
904 
905 	jz4740_mmc_write_irq_reg(host, ~0);
906 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_END_CMD_RES, true);
907 
908 	host->state = JZ4740_MMC_STATE_READ_RESPONSE;
909 	set_bit(0, &host->waiting);
910 	mod_timer(&host->timeout_timer,
911 		  jiffies + msecs_to_jiffies(JZ_MMC_REQ_TIMEOUT_MS));
912 	jz4740_mmc_send_command(host, req->cmd);
913 }
914 
915 static void jz4740_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
916 {
917 	struct jz4740_mmc_host *host = mmc_priv(mmc);
918 	if (ios->clock)
919 		jz4740_mmc_set_clock_rate(host, ios->clock);
920 
921 	switch (ios->power_mode) {
922 	case MMC_POWER_UP:
923 		jz4740_mmc_reset(host);
924 		if (!IS_ERR(mmc->supply.vmmc))
925 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
926 		host->cmdat |= JZ_MMC_CMDAT_INIT;
927 		clk_prepare_enable(host->clk);
928 		break;
929 	case MMC_POWER_ON:
930 		break;
931 	default:
932 		if (!IS_ERR(mmc->supply.vmmc))
933 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
934 		clk_disable_unprepare(host->clk);
935 		break;
936 	}
937 
938 	switch (ios->bus_width) {
939 	case MMC_BUS_WIDTH_1:
940 		host->cmdat &= ~JZ_MMC_CMDAT_BUS_WIDTH_MASK;
941 		break;
942 	case MMC_BUS_WIDTH_4:
943 		host->cmdat &= ~JZ_MMC_CMDAT_BUS_WIDTH_MASK;
944 		host->cmdat |= JZ_MMC_CMDAT_BUS_WIDTH_4BIT;
945 		break;
946 	case MMC_BUS_WIDTH_8:
947 		host->cmdat &= ~JZ_MMC_CMDAT_BUS_WIDTH_MASK;
948 		host->cmdat |= JZ_MMC_CMDAT_BUS_WIDTH_8BIT;
949 		break;
950 	default:
951 		break;
952 	}
953 }
954 
955 static void jz4740_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
956 {
957 	struct jz4740_mmc_host *host = mmc_priv(mmc);
958 	jz4740_mmc_set_irq_enabled(host, JZ_MMC_IRQ_SDIO, enable);
959 }
960 
961 static const struct mmc_host_ops jz4740_mmc_ops = {
962 	.request	= jz4740_mmc_request,
963 	.pre_req	= jz4740_mmc_pre_request,
964 	.post_req	= jz4740_mmc_post_request,
965 	.set_ios	= jz4740_mmc_set_ios,
966 	.get_ro		= mmc_gpio_get_ro,
967 	.get_cd		= mmc_gpio_get_cd,
968 	.enable_sdio_irq = jz4740_mmc_enable_sdio_irq,
969 };
970 
971 static const struct of_device_id jz4740_mmc_of_match[] = {
972 	{ .compatible = "ingenic,jz4740-mmc", .data = (void *) JZ_MMC_JZ4740 },
973 	{ .compatible = "ingenic,jz4725b-mmc", .data = (void *)JZ_MMC_JZ4725B },
974 	{ .compatible = "ingenic,jz4760-mmc", .data = (void *) JZ_MMC_JZ4760 },
975 	{ .compatible = "ingenic,jz4775-mmc", .data = (void *) JZ_MMC_JZ4780 },
976 	{ .compatible = "ingenic,jz4780-mmc", .data = (void *) JZ_MMC_JZ4780 },
977 	{ .compatible = "ingenic,x1000-mmc", .data = (void *) JZ_MMC_X1000 },
978 	{},
979 };
980 MODULE_DEVICE_TABLE(of, jz4740_mmc_of_match);
981 
982 static int jz4740_mmc_probe(struct platform_device* pdev)
983 {
984 	int ret;
985 	struct mmc_host *mmc;
986 	struct jz4740_mmc_host *host;
987 	const struct of_device_id *match;
988 
989 	mmc = mmc_alloc_host(sizeof(struct jz4740_mmc_host), &pdev->dev);
990 	if (!mmc) {
991 		dev_err(&pdev->dev, "Failed to alloc mmc host structure\n");
992 		return -ENOMEM;
993 	}
994 
995 	host = mmc_priv(mmc);
996 
997 	match = of_match_device(jz4740_mmc_of_match, &pdev->dev);
998 	if (match) {
999 		host->version = (enum jz4740_mmc_version)match->data;
1000 	} else {
1001 		/* JZ4740 should be the only one using legacy probe */
1002 		host->version = JZ_MMC_JZ4740;
1003 	}
1004 
1005 	ret = mmc_of_parse(mmc);
1006 	if (ret) {
1007 		dev_err_probe(&pdev->dev, ret, "could not parse device properties\n");
1008 		goto err_free_host;
1009 	}
1010 
1011 	mmc_regulator_get_supply(mmc);
1012 
1013 	host->irq = platform_get_irq(pdev, 0);
1014 	if (host->irq < 0) {
1015 		ret = host->irq;
1016 		goto err_free_host;
1017 	}
1018 
1019 	host->clk = devm_clk_get(&pdev->dev, "mmc");
1020 	if (IS_ERR(host->clk)) {
1021 		ret = PTR_ERR(host->clk);
1022 		dev_err(&pdev->dev, "Failed to get mmc clock\n");
1023 		goto err_free_host;
1024 	}
1025 
1026 	host->mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1027 	host->base = devm_ioremap_resource(&pdev->dev, host->mem_res);
1028 	if (IS_ERR(host->base)) {
1029 		ret = PTR_ERR(host->base);
1030 		goto err_free_host;
1031 	}
1032 
1033 	mmc->ops = &jz4740_mmc_ops;
1034 	if (!mmc->f_max)
1035 		mmc->f_max = JZ_MMC_CLK_RATE;
1036 	mmc->f_min = mmc->f_max / 128;
1037 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1038 
1039 	/*
1040 	 * We use a fixed timeout of 5s, hence inform the core about it. A
1041 	 * future improvement should instead respect the cmd->busy_timeout.
1042 	 */
1043 	mmc->max_busy_timeout = JZ_MMC_REQ_TIMEOUT_MS;
1044 
1045 	mmc->max_blk_size = (1 << 10) - 1;
1046 	mmc->max_blk_count = (1 << 15) - 1;
1047 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1048 
1049 	mmc->max_segs = 128;
1050 	mmc->max_seg_size = mmc->max_req_size;
1051 
1052 	host->mmc = mmc;
1053 	host->pdev = pdev;
1054 	spin_lock_init(&host->lock);
1055 	host->irq_mask = ~0;
1056 
1057 	jz4740_mmc_reset(host);
1058 
1059 	ret = request_threaded_irq(host->irq, jz_mmc_irq, jz_mmc_irq_worker, 0,
1060 			dev_name(&pdev->dev), host);
1061 	if (ret) {
1062 		dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
1063 		goto err_free_host;
1064 	}
1065 
1066 	jz4740_mmc_clock_disable(host);
1067 	timer_setup(&host->timeout_timer, jz4740_mmc_timeout, 0);
1068 
1069 	ret = jz4740_mmc_acquire_dma_channels(host);
1070 	if (ret == -EPROBE_DEFER)
1071 		goto err_free_irq;
1072 	host->use_dma = !ret;
1073 
1074 	platform_set_drvdata(pdev, host);
1075 	ret = mmc_add_host(mmc);
1076 
1077 	if (ret) {
1078 		dev_err(&pdev->dev, "Failed to add mmc host: %d\n", ret);
1079 		goto err_release_dma;
1080 	}
1081 	dev_info(&pdev->dev, "Ingenic SD/MMC card driver registered\n");
1082 
1083 	dev_info(&pdev->dev, "Using %s, %d-bit mode\n",
1084 		 host->use_dma ? "DMA" : "PIO",
1085 		 (mmc->caps & MMC_CAP_8_BIT_DATA) ? 8 :
1086 		 ((mmc->caps & MMC_CAP_4_BIT_DATA) ? 4 : 1));
1087 
1088 	return 0;
1089 
1090 err_release_dma:
1091 	if (host->use_dma)
1092 		jz4740_mmc_release_dma_channels(host);
1093 err_free_irq:
1094 	free_irq(host->irq, host);
1095 err_free_host:
1096 	mmc_free_host(mmc);
1097 
1098 	return ret;
1099 }
1100 
1101 static int jz4740_mmc_remove(struct platform_device *pdev)
1102 {
1103 	struct jz4740_mmc_host *host = platform_get_drvdata(pdev);
1104 
1105 	del_timer_sync(&host->timeout_timer);
1106 	jz4740_mmc_set_irq_enabled(host, 0xff, false);
1107 	jz4740_mmc_reset(host);
1108 
1109 	mmc_remove_host(host->mmc);
1110 
1111 	free_irq(host->irq, host);
1112 
1113 	if (host->use_dma)
1114 		jz4740_mmc_release_dma_channels(host);
1115 
1116 	mmc_free_host(host->mmc);
1117 
1118 	return 0;
1119 }
1120 
1121 static int jz4740_mmc_suspend(struct device *dev)
1122 {
1123 	return pinctrl_pm_select_sleep_state(dev);
1124 }
1125 
1126 static int jz4740_mmc_resume(struct device *dev)
1127 {
1128 	return pinctrl_select_default_state(dev);
1129 }
1130 
1131 static DEFINE_SIMPLE_DEV_PM_OPS(jz4740_mmc_pm_ops, jz4740_mmc_suspend,
1132 				jz4740_mmc_resume);
1133 
1134 static struct platform_driver jz4740_mmc_driver = {
1135 	.probe = jz4740_mmc_probe,
1136 	.remove = jz4740_mmc_remove,
1137 	.driver = {
1138 		.name = "jz4740-mmc",
1139 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1140 		.of_match_table = of_match_ptr(jz4740_mmc_of_match),
1141 		.pm = pm_sleep_ptr(&jz4740_mmc_pm_ops),
1142 	},
1143 };
1144 
1145 module_platform_driver(jz4740_mmc_driver);
1146 
1147 MODULE_DESCRIPTION("JZ4740 SD/MMC controller driver");
1148 MODULE_LICENSE("GPL");
1149 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
1150