xref: /linux/drivers/mmc/host/mxcmmc.c (revision 257ca10c7317d4a424e48bb95d14ca53a1f1dd6f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mmc/host/mxcmmc.c - Freescale i.MX MMCI driver
4  *
5  *  This is a driver for the SDHC controller found in Freescale MX2/MX3
6  *  SoCs. It is basically the same hardware as found on MX1 (imxmmc.c).
7  *  Unlike the hardware found on MX1, this hardware just works and does
8  *  not need all the quirks found in imxmmc.c, hence the separate driver.
9  *
10  *  Copyright (C) 2008 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
11  *  Copyright (C) 2006 Pavel Pisa, PiKRON <ppisa@pikron.com>
12  *
13  *  derived from pxamci.c by Russell King
14  */
15 
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/ioport.h>
19 #include <linux/platform_device.h>
20 #include <linux/highmem.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/blkdev.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/mmc/host.h>
26 #include <linux/mmc/card.h>
27 #include <linux/delay.h>
28 #include <linux/clk.h>
29 #include <linux/io.h>
30 #include <linux/regulator/consumer.h>
31 #include <linux/dmaengine.h>
32 #include <linux/types.h>
33 #include <linux/of.h>
34 #include <linux/of_dma.h>
35 #include <linux/mmc/slot-gpio.h>
36 
37 #include <asm/dma.h>
38 #include <asm/irq.h>
39 #include <linux/platform_data/mmc-mxcmmc.h>
40 
41 #include <linux/dma/imx-dma.h>
42 
43 #define DRIVER_NAME "mxc-mmc"
44 #define MXCMCI_TIMEOUT_MS 10000
45 
46 #define MMC_REG_STR_STP_CLK		0x00
47 #define MMC_REG_STATUS			0x04
48 #define MMC_REG_CLK_RATE		0x08
49 #define MMC_REG_CMD_DAT_CONT		0x0C
50 #define MMC_REG_RES_TO			0x10
51 #define MMC_REG_READ_TO			0x14
52 #define MMC_REG_BLK_LEN			0x18
53 #define MMC_REG_NOB			0x1C
54 #define MMC_REG_REV_NO			0x20
55 #define MMC_REG_INT_CNTR		0x24
56 #define MMC_REG_CMD			0x28
57 #define MMC_REG_ARG			0x2C
58 #define MMC_REG_RES_FIFO		0x34
59 #define MMC_REG_BUFFER_ACCESS		0x38
60 
61 #define STR_STP_CLK_RESET               (1 << 3)
62 #define STR_STP_CLK_START_CLK           (1 << 1)
63 #define STR_STP_CLK_STOP_CLK            (1 << 0)
64 
65 #define STATUS_CARD_INSERTION		(1 << 31)
66 #define STATUS_CARD_REMOVAL		(1 << 30)
67 #define STATUS_YBUF_EMPTY		(1 << 29)
68 #define STATUS_XBUF_EMPTY		(1 << 28)
69 #define STATUS_YBUF_FULL		(1 << 27)
70 #define STATUS_XBUF_FULL		(1 << 26)
71 #define STATUS_BUF_UND_RUN		(1 << 25)
72 #define STATUS_BUF_OVFL			(1 << 24)
73 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
74 #define STATUS_END_CMD_RESP		(1 << 13)
75 #define STATUS_WRITE_OP_DONE		(1 << 12)
76 #define STATUS_DATA_TRANS_DONE		(1 << 11)
77 #define STATUS_READ_OP_DONE		(1 << 11)
78 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
79 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
80 #define STATUS_BUF_READ_RDY		(1 << 7)
81 #define STATUS_BUF_WRITE_RDY		(1 << 6)
82 #define STATUS_RESP_CRC_ERR		(1 << 5)
83 #define STATUS_CRC_READ_ERR		(1 << 3)
84 #define STATUS_CRC_WRITE_ERR		(1 << 2)
85 #define STATUS_TIME_OUT_RESP		(1 << 1)
86 #define STATUS_TIME_OUT_READ		(1 << 0)
87 #define STATUS_ERR_MASK			0x2f
88 
89 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
90 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
91 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
92 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
93 #define CMD_DAT_CONT_INIT		(1 << 7)
94 #define CMD_DAT_CONT_WRITE		(1 << 4)
95 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
96 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
97 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
98 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
99 
100 #define INT_SDIO_INT_WKP_EN		(1 << 18)
101 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
102 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
103 #define INT_CARD_INSERTION_EN		(1 << 15)
104 #define INT_CARD_REMOVAL_EN		(1 << 14)
105 #define INT_SDIO_IRQ_EN			(1 << 13)
106 #define INT_DAT0_EN			(1 << 12)
107 #define INT_BUF_READ_EN			(1 << 4)
108 #define INT_BUF_WRITE_EN		(1 << 3)
109 #define INT_END_CMD_RES_EN		(1 << 2)
110 #define INT_WRITE_OP_DONE_EN		(1 << 1)
111 #define INT_READ_OP_EN			(1 << 0)
112 
113 enum mxcmci_type {
114 	IMX21_MMC,
115 	IMX31_MMC,
116 	MPC512X_MMC,
117 };
118 
119 struct mxcmci_host {
120 	struct mmc_host		*mmc;
121 	void __iomem		*base;
122 	dma_addr_t		phys_base;
123 	int			detect_irq;
124 	struct dma_chan		*dma;
125 	struct dma_async_tx_descriptor *desc;
126 	int			do_dma;
127 	int			default_irq_mask;
128 	int			use_sdio;
129 	unsigned int		power_mode;
130 	struct imxmmc_platform_data *pdata;
131 
132 	struct mmc_request	*req;
133 	struct mmc_command	*cmd;
134 	struct mmc_data		*data;
135 
136 	unsigned int		datasize;
137 	unsigned int		dma_dir;
138 
139 	u16			rev_no;
140 	unsigned int		cmdat;
141 
142 	struct clk		*clk_ipg;
143 	struct clk		*clk_per;
144 
145 	int			clock;
146 
147 	struct work_struct	datawork;
148 	spinlock_t		lock;
149 
150 	int			burstlen;
151 	int			dmareq;
152 	struct dma_slave_config dma_slave_config;
153 	struct imx_dma_data	dma_data;
154 
155 	struct timer_list	watchdog;
156 	enum mxcmci_type	devtype;
157 };
158 
159 static const struct of_device_id mxcmci_of_match[] = {
160 	{
161 		.compatible = "fsl,imx21-mmc",
162 		.data = (void *) IMX21_MMC,
163 	}, {
164 		.compatible = "fsl,imx31-mmc",
165 		.data = (void *) IMX31_MMC,
166 	}, {
167 		.compatible = "fsl,mpc5121-sdhc",
168 		.data = (void *) MPC512X_MMC,
169 	}, {
170 		/* sentinel */
171 	}
172 };
173 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
174 
175 static inline int is_imx31_mmc(struct mxcmci_host *host)
176 {
177 	return host->devtype == IMX31_MMC;
178 }
179 
180 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
181 {
182 	return host->devtype == MPC512X_MMC;
183 }
184 
185 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
186 {
187 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
188 		return ioread32be(host->base + reg);
189 	else
190 		return readl(host->base + reg);
191 }
192 
193 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
194 {
195 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
196 		iowrite32be(val, host->base + reg);
197 	else
198 		writel(val, host->base + reg);
199 }
200 
201 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
202 {
203 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
204 		return ioread32be(host->base + reg);
205 	else
206 		return readw(host->base + reg);
207 }
208 
209 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
210 {
211 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
212 		iowrite32be(val, host->base + reg);
213 	else
214 		writew(val, host->base + reg);
215 }
216 
217 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
218 
219 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
220 {
221 	if (!IS_ERR(host->mmc->supply.vmmc)) {
222 		if (host->power_mode == MMC_POWER_UP)
223 			mmc_regulator_set_ocr(host->mmc,
224 					      host->mmc->supply.vmmc, vdd);
225 		else if (host->power_mode == MMC_POWER_OFF)
226 			mmc_regulator_set_ocr(host->mmc,
227 					      host->mmc->supply.vmmc, 0);
228 	}
229 
230 	if (host->pdata && host->pdata->setpower)
231 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
232 }
233 
234 static inline int mxcmci_use_dma(struct mxcmci_host *host)
235 {
236 	return host->do_dma;
237 }
238 
239 static void mxcmci_softreset(struct mxcmci_host *host)
240 {
241 	int i;
242 
243 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
244 
245 	/* reset sequence */
246 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
247 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
248 			MMC_REG_STR_STP_CLK);
249 
250 	for (i = 0; i < 8; i++)
251 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
252 
253 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
254 }
255 
256 #if IS_ENABLED(CONFIG_PPC_MPC512x)
257 static inline void buffer_swap32(u32 *buf, int len)
258 {
259 	int i;
260 
261 	for (i = 0; i < ((len + 3) / 4); i++) {
262 		*buf = swab32(*buf);
263 		buf++;
264 	}
265 }
266 
267 static void mxcmci_swap_buffers(struct mmc_data *data)
268 {
269 	struct scatterlist *sg;
270 	int i;
271 
272 	for_each_sg(data->sg, sg, data->sg_len, i)
273 		buffer_swap32(sg_virt(sg), sg->length);
274 }
275 #else
276 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
277 #endif
278 
279 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
280 {
281 	unsigned int nob = data->blocks;
282 	unsigned int blksz = data->blksz;
283 	unsigned int datasize = nob * blksz;
284 	struct scatterlist *sg;
285 	enum dma_transfer_direction slave_dirn;
286 	int i, nents;
287 
288 	host->data = data;
289 	data->bytes_xfered = 0;
290 
291 	mxcmci_writew(host, nob, MMC_REG_NOB);
292 	mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
293 	host->datasize = datasize;
294 
295 	if (!mxcmci_use_dma(host))
296 		return 0;
297 
298 	for_each_sg(data->sg, sg, data->sg_len, i) {
299 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
300 			host->do_dma = 0;
301 			return 0;
302 		}
303 	}
304 
305 	if (data->flags & MMC_DATA_READ) {
306 		host->dma_dir = DMA_FROM_DEVICE;
307 		slave_dirn = DMA_DEV_TO_MEM;
308 	} else {
309 		host->dma_dir = DMA_TO_DEVICE;
310 		slave_dirn = DMA_MEM_TO_DEV;
311 
312 		mxcmci_swap_buffers(data);
313 	}
314 
315 	nents = dma_map_sg(host->dma->device->dev, data->sg,
316 				     data->sg_len,  host->dma_dir);
317 	if (nents != data->sg_len)
318 		return -EINVAL;
319 
320 	host->desc = dmaengine_prep_slave_sg(host->dma,
321 		data->sg, data->sg_len, slave_dirn,
322 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
323 
324 	if (!host->desc) {
325 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
326 				host->dma_dir);
327 		host->do_dma = 0;
328 		return 0; /* Fall back to PIO */
329 	}
330 	wmb();
331 
332 	dmaengine_submit(host->desc);
333 	dma_async_issue_pending(host->dma);
334 
335 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
336 
337 	return 0;
338 }
339 
340 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
341 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
342 
343 static void mxcmci_dma_callback(void *data)
344 {
345 	struct mxcmci_host *host = data;
346 	u32 stat;
347 
348 	del_timer(&host->watchdog);
349 
350 	stat = mxcmci_readl(host, MMC_REG_STATUS);
351 
352 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
353 
354 	mxcmci_data_done(host, stat);
355 }
356 
357 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
358 		unsigned int cmdat)
359 {
360 	u32 int_cntr = host->default_irq_mask;
361 	unsigned long flags;
362 
363 	WARN_ON(host->cmd != NULL);
364 	host->cmd = cmd;
365 
366 	switch (mmc_resp_type(cmd)) {
367 	case MMC_RSP_R1: /* short CRC, OPCODE */
368 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
369 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
370 		break;
371 	case MMC_RSP_R2: /* long 136 bit + CRC */
372 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
373 		break;
374 	case MMC_RSP_R3: /* short */
375 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
376 		break;
377 	case MMC_RSP_NONE:
378 		break;
379 	default:
380 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
381 				mmc_resp_type(cmd));
382 		cmd->error = -EINVAL;
383 		return -EINVAL;
384 	}
385 
386 	int_cntr = INT_END_CMD_RES_EN;
387 
388 	if (mxcmci_use_dma(host)) {
389 		if (host->dma_dir == DMA_FROM_DEVICE) {
390 			host->desc->callback = mxcmci_dma_callback;
391 			host->desc->callback_param = host;
392 		} else {
393 			int_cntr |= INT_WRITE_OP_DONE_EN;
394 		}
395 	}
396 
397 	spin_lock_irqsave(&host->lock, flags);
398 	if (host->use_sdio)
399 		int_cntr |= INT_SDIO_IRQ_EN;
400 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
401 	spin_unlock_irqrestore(&host->lock, flags);
402 
403 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
404 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
405 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
406 
407 	return 0;
408 }
409 
410 static void mxcmci_finish_request(struct mxcmci_host *host,
411 		struct mmc_request *req)
412 {
413 	u32 int_cntr = host->default_irq_mask;
414 	unsigned long flags;
415 
416 	spin_lock_irqsave(&host->lock, flags);
417 	if (host->use_sdio)
418 		int_cntr |= INT_SDIO_IRQ_EN;
419 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
420 	spin_unlock_irqrestore(&host->lock, flags);
421 
422 	host->req = NULL;
423 	host->cmd = NULL;
424 	host->data = NULL;
425 
426 	mmc_request_done(host->mmc, req);
427 }
428 
429 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
430 {
431 	struct mmc_data *data = host->data;
432 	int data_error;
433 
434 	if (mxcmci_use_dma(host)) {
435 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
436 				host->dma_dir);
437 		mxcmci_swap_buffers(data);
438 	}
439 
440 	if (stat & STATUS_ERR_MASK) {
441 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
442 				stat);
443 		if (stat & STATUS_CRC_READ_ERR) {
444 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
445 			data->error = -EILSEQ;
446 		} else if (stat & STATUS_CRC_WRITE_ERR) {
447 			u32 err_code = (stat >> 9) & 0x3;
448 			if (err_code == 2) { /* No CRC response */
449 				dev_err(mmc_dev(host->mmc),
450 					"%s: No CRC -ETIMEDOUT\n", __func__);
451 				data->error = -ETIMEDOUT;
452 			} else {
453 				dev_err(mmc_dev(host->mmc),
454 					"%s: -EILSEQ\n", __func__);
455 				data->error = -EILSEQ;
456 			}
457 		} else if (stat & STATUS_TIME_OUT_READ) {
458 			dev_err(mmc_dev(host->mmc),
459 				"%s: read -ETIMEDOUT\n", __func__);
460 			data->error = -ETIMEDOUT;
461 		} else {
462 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
463 			data->error = -EIO;
464 		}
465 	} else {
466 		data->bytes_xfered = host->datasize;
467 	}
468 
469 	data_error = data->error;
470 
471 	host->data = NULL;
472 
473 	return data_error;
474 }
475 
476 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
477 {
478 	struct mmc_command *cmd = host->cmd;
479 	int i;
480 	u32 a, b, c;
481 
482 	if (!cmd)
483 		return;
484 
485 	if (stat & STATUS_TIME_OUT_RESP) {
486 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
487 		cmd->error = -ETIMEDOUT;
488 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
489 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
490 		cmd->error = -EILSEQ;
491 	}
492 
493 	if (cmd->flags & MMC_RSP_PRESENT) {
494 		if (cmd->flags & MMC_RSP_136) {
495 			for (i = 0; i < 4; i++) {
496 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
497 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
498 				cmd->resp[i] = a << 16 | b;
499 			}
500 		} else {
501 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
502 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
503 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
504 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
505 		}
506 	}
507 }
508 
509 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
510 {
511 	u32 stat;
512 	unsigned long timeout = jiffies + HZ;
513 
514 	do {
515 		stat = mxcmci_readl(host, MMC_REG_STATUS);
516 		if (stat & STATUS_ERR_MASK)
517 			return stat;
518 		if (time_after(jiffies, timeout)) {
519 			mxcmci_softreset(host);
520 			mxcmci_set_clk_rate(host, host->clock);
521 			return STATUS_TIME_OUT_READ;
522 		}
523 		if (stat & mask)
524 			return 0;
525 		cpu_relax();
526 	} while (1);
527 }
528 
529 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
530 {
531 	unsigned int stat;
532 	u32 *buf = _buf;
533 
534 	while (bytes > 3) {
535 		stat = mxcmci_poll_status(host,
536 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
537 		if (stat)
538 			return stat;
539 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
540 		bytes -= 4;
541 	}
542 
543 	if (bytes) {
544 		u8 *b = (u8 *)buf;
545 		u32 tmp;
546 
547 		stat = mxcmci_poll_status(host,
548 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
549 		if (stat)
550 			return stat;
551 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
552 		memcpy(b, &tmp, bytes);
553 	}
554 
555 	return 0;
556 }
557 
558 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
559 {
560 	unsigned int stat;
561 	u32 *buf = _buf;
562 
563 	while (bytes > 3) {
564 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
565 		if (stat)
566 			return stat;
567 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
568 		bytes -= 4;
569 	}
570 
571 	if (bytes) {
572 		u8 *b = (u8 *)buf;
573 		u32 tmp;
574 
575 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
576 		if (stat)
577 			return stat;
578 
579 		memcpy(&tmp, b, bytes);
580 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
581 	}
582 
583 	return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
584 }
585 
586 static int mxcmci_transfer_data(struct mxcmci_host *host)
587 {
588 	struct mmc_data *data = host->req->data;
589 	struct scatterlist *sg;
590 	int stat, i;
591 
592 	host->data = data;
593 	host->datasize = 0;
594 
595 	if (data->flags & MMC_DATA_READ) {
596 		for_each_sg(data->sg, sg, data->sg_len, i) {
597 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
598 			if (stat)
599 				return stat;
600 			host->datasize += sg->length;
601 		}
602 	} else {
603 		for_each_sg(data->sg, sg, data->sg_len, i) {
604 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
605 			if (stat)
606 				return stat;
607 			host->datasize += sg->length;
608 		}
609 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
610 		if (stat)
611 			return stat;
612 	}
613 	return 0;
614 }
615 
616 static void mxcmci_datawork(struct work_struct *work)
617 {
618 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
619 						  datawork);
620 	int datastat = mxcmci_transfer_data(host);
621 
622 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
623 		MMC_REG_STATUS);
624 	mxcmci_finish_data(host, datastat);
625 
626 	if (host->req->stop) {
627 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
628 			mxcmci_finish_request(host, host->req);
629 			return;
630 		}
631 	} else {
632 		mxcmci_finish_request(host, host->req);
633 	}
634 }
635 
636 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
637 {
638 	struct mmc_request *req;
639 	int data_error;
640 	unsigned long flags;
641 
642 	spin_lock_irqsave(&host->lock, flags);
643 
644 	if (!host->data) {
645 		spin_unlock_irqrestore(&host->lock, flags);
646 		return;
647 	}
648 
649 	if (!host->req) {
650 		spin_unlock_irqrestore(&host->lock, flags);
651 		return;
652 	}
653 
654 	req = host->req;
655 	if (!req->stop)
656 		host->req = NULL; /* we will handle finish req below */
657 
658 	data_error = mxcmci_finish_data(host, stat);
659 
660 	spin_unlock_irqrestore(&host->lock, flags);
661 
662 	if (data_error)
663 		return;
664 
665 	mxcmci_read_response(host, stat);
666 	host->cmd = NULL;
667 
668 	if (req->stop) {
669 		if (mxcmci_start_cmd(host, req->stop, 0)) {
670 			mxcmci_finish_request(host, req);
671 			return;
672 		}
673 	} else {
674 		mxcmci_finish_request(host, req);
675 	}
676 }
677 
678 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
679 {
680 	mxcmci_read_response(host, stat);
681 	host->cmd = NULL;
682 
683 	if (!host->data && host->req) {
684 		mxcmci_finish_request(host, host->req);
685 		return;
686 	}
687 
688 	/* For the DMA case the DMA engine handles the data transfer
689 	 * automatically. For non DMA we have to do it ourselves.
690 	 * Don't do it in interrupt context though.
691 	 */
692 	if (!mxcmci_use_dma(host) && host->data)
693 		schedule_work(&host->datawork);
694 
695 }
696 
697 static irqreturn_t mxcmci_irq(int irq, void *devid)
698 {
699 	struct mxcmci_host *host = devid;
700 	bool sdio_irq;
701 	u32 stat;
702 
703 	stat = mxcmci_readl(host, MMC_REG_STATUS);
704 	mxcmci_writel(host,
705 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
706 			 STATUS_WRITE_OP_DONE),
707 		MMC_REG_STATUS);
708 
709 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
710 
711 	spin_lock(&host->lock);
712 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
713 	spin_unlock(&host->lock);
714 
715 	if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
716 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
717 
718 	if (sdio_irq) {
719 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
720 		mmc_signal_sdio_irq(host->mmc);
721 	}
722 
723 	if (stat & STATUS_END_CMD_RESP)
724 		mxcmci_cmd_done(host, stat);
725 
726 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
727 		del_timer(&host->watchdog);
728 		mxcmci_data_done(host, stat);
729 	}
730 
731 	if (host->default_irq_mask &&
732 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
733 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
734 
735 	return IRQ_HANDLED;
736 }
737 
738 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
739 {
740 	struct mxcmci_host *host = mmc_priv(mmc);
741 	unsigned int cmdat = host->cmdat;
742 	int error;
743 
744 	WARN_ON(host->req != NULL);
745 
746 	host->req = req;
747 	host->cmdat &= ~CMD_DAT_CONT_INIT;
748 
749 	if (host->dma)
750 		host->do_dma = 1;
751 
752 	if (req->data) {
753 		error = mxcmci_setup_data(host, req->data);
754 		if (error) {
755 			req->cmd->error = error;
756 			goto out;
757 		}
758 
759 
760 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
761 
762 		if (req->data->flags & MMC_DATA_WRITE)
763 			cmdat |= CMD_DAT_CONT_WRITE;
764 	}
765 
766 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
767 
768 out:
769 	if (error)
770 		mxcmci_finish_request(host, req);
771 }
772 
773 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
774 {
775 	unsigned int divider;
776 	int prescaler = 0;
777 	unsigned int clk_in = clk_get_rate(host->clk_per);
778 
779 	while (prescaler <= 0x800) {
780 		for (divider = 1; divider <= 0xF; divider++) {
781 			int x;
782 
783 			x = (clk_in / (divider + 1));
784 
785 			if (prescaler)
786 				x /= (prescaler * 2);
787 
788 			if (x <= clk_ios)
789 				break;
790 		}
791 		if (divider < 0x10)
792 			break;
793 
794 		if (prescaler == 0)
795 			prescaler = 1;
796 		else
797 			prescaler <<= 1;
798 	}
799 
800 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
801 
802 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
803 			prescaler, divider, clk_in, clk_ios);
804 }
805 
806 static int mxcmci_setup_dma(struct mmc_host *mmc)
807 {
808 	struct mxcmci_host *host = mmc_priv(mmc);
809 	struct dma_slave_config *config = &host->dma_slave_config;
810 
811 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
812 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
813 	config->dst_addr_width = 4;
814 	config->src_addr_width = 4;
815 	config->dst_maxburst = host->burstlen;
816 	config->src_maxburst = host->burstlen;
817 	config->device_fc = false;
818 
819 	return dmaengine_slave_config(host->dma, config);
820 }
821 
822 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
823 {
824 	struct mxcmci_host *host = mmc_priv(mmc);
825 	int burstlen, ret;
826 
827 	/*
828 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
829 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
830 	 */
831 	if (ios->bus_width == MMC_BUS_WIDTH_4)
832 		burstlen = 16;
833 	else
834 		burstlen = 4;
835 
836 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
837 		host->burstlen = burstlen;
838 		ret = mxcmci_setup_dma(mmc);
839 		if (ret) {
840 			dev_err(mmc_dev(host->mmc),
841 				"failed to config DMA channel. Falling back to PIO\n");
842 			dma_release_channel(host->dma);
843 			host->do_dma = 0;
844 			host->dma = NULL;
845 		}
846 	}
847 
848 	if (ios->bus_width == MMC_BUS_WIDTH_4)
849 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
850 	else
851 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
852 
853 	if (host->power_mode != ios->power_mode) {
854 		host->power_mode = ios->power_mode;
855 		mxcmci_set_power(host, ios->vdd);
856 
857 		if (ios->power_mode == MMC_POWER_ON)
858 			host->cmdat |= CMD_DAT_CONT_INIT;
859 	}
860 
861 	if (ios->clock) {
862 		mxcmci_set_clk_rate(host, ios->clock);
863 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
864 	} else {
865 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
866 	}
867 
868 	host->clock = ios->clock;
869 }
870 
871 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
872 {
873 	struct mmc_host *mmc = data;
874 
875 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
876 
877 	mmc_detect_change(mmc, msecs_to_jiffies(250));
878 	return IRQ_HANDLED;
879 }
880 
881 static int mxcmci_get_ro(struct mmc_host *mmc)
882 {
883 	struct mxcmci_host *host = mmc_priv(mmc);
884 
885 	if (host->pdata && host->pdata->get_ro)
886 		return !!host->pdata->get_ro(mmc_dev(mmc));
887 	/*
888 	 * If board doesn't support read only detection (no mmc_gpio
889 	 * context or gpio is invalid), then let the mmc core decide
890 	 * what to do.
891 	 */
892 	return mmc_gpio_get_ro(mmc);
893 }
894 
895 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
896 {
897 	struct mxcmci_host *host = mmc_priv(mmc);
898 	unsigned long flags;
899 	u32 int_cntr;
900 
901 	spin_lock_irqsave(&host->lock, flags);
902 	host->use_sdio = enable;
903 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
904 
905 	if (enable)
906 		int_cntr |= INT_SDIO_IRQ_EN;
907 	else
908 		int_cntr &= ~INT_SDIO_IRQ_EN;
909 
910 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
911 	spin_unlock_irqrestore(&host->lock, flags);
912 }
913 
914 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
915 {
916 	struct mxcmci_host *mxcmci = mmc_priv(host);
917 
918 	/*
919 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
920 	 * multi-block transfers when connected SDIO peripheral doesn't
921 	 * drive the BUSY line as required by the specs.
922 	 * One way to prevent this is to only allow 1-bit transfers.
923 	 */
924 
925 	if (is_imx31_mmc(mxcmci) && mmc_card_sdio(card))
926 		host->caps &= ~MMC_CAP_4_BIT_DATA;
927 	else
928 		host->caps |= MMC_CAP_4_BIT_DATA;
929 }
930 
931 static bool filter(struct dma_chan *chan, void *param)
932 {
933 	struct mxcmci_host *host = param;
934 
935 	if (!imx_dma_is_general_purpose(chan))
936 		return false;
937 
938 	chan->private = &host->dma_data;
939 
940 	return true;
941 }
942 
943 static void mxcmci_watchdog(struct timer_list *t)
944 {
945 	struct mxcmci_host *host = from_timer(host, t, watchdog);
946 	struct mmc_request *req = host->req;
947 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
948 
949 	if (host->dma_dir == DMA_FROM_DEVICE) {
950 		dmaengine_terminate_all(host->dma);
951 		dev_err(mmc_dev(host->mmc),
952 			"%s: read time out (status = 0x%08x)\n",
953 			__func__, stat);
954 	} else {
955 		dev_err(mmc_dev(host->mmc),
956 			"%s: write time out (status = 0x%08x)\n",
957 			__func__, stat);
958 		mxcmci_softreset(host);
959 	}
960 
961 	/* Mark transfer as erroneus and inform the upper layers */
962 
963 	if (host->data)
964 		host->data->error = -ETIMEDOUT;
965 	host->req = NULL;
966 	host->cmd = NULL;
967 	host->data = NULL;
968 	mmc_request_done(host->mmc, req);
969 }
970 
971 static const struct mmc_host_ops mxcmci_ops = {
972 	.request		= mxcmci_request,
973 	.set_ios		= mxcmci_set_ios,
974 	.get_ro			= mxcmci_get_ro,
975 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
976 	.init_card		= mxcmci_init_card,
977 };
978 
979 static int mxcmci_probe(struct platform_device *pdev)
980 {
981 	struct mmc_host *mmc;
982 	struct mxcmci_host *host;
983 	struct resource *res;
984 	int ret = 0, irq;
985 	bool dat3_card_detect = false;
986 	dma_cap_mask_t mask;
987 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
988 
989 	pr_info("i.MX/MPC512x SDHC driver\n");
990 
991 	irq = platform_get_irq(pdev, 0);
992 	if (irq < 0)
993 		return irq;
994 
995 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
996 	if (!mmc)
997 		return -ENOMEM;
998 
999 	host = mmc_priv(mmc);
1000 
1001 	host->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1002 	if (IS_ERR(host->base)) {
1003 		ret = PTR_ERR(host->base);
1004 		goto out_free;
1005 	}
1006 
1007 	host->phys_base = res->start;
1008 
1009 	ret = mmc_of_parse(mmc);
1010 	if (ret)
1011 		goto out_free;
1012 	mmc->ops = &mxcmci_ops;
1013 
1014 	/* For devicetree parsing, the bus width is read from devicetree */
1015 	if (pdata)
1016 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1017 	else
1018 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1019 
1020 	/* MMC core transfer sizes tunable parameters */
1021 	mmc->max_blk_size = 2048;
1022 	mmc->max_blk_count = 65535;
1023 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1024 	mmc->max_seg_size = mmc->max_req_size;
1025 
1026 	host->devtype = (uintptr_t)of_device_get_match_data(&pdev->dev);
1027 
1028 	/* adjust max_segs after devtype detection */
1029 	if (!is_mpc512x_mmc(host))
1030 		mmc->max_segs = 64;
1031 
1032 	host->mmc = mmc;
1033 	host->pdata = pdata;
1034 	spin_lock_init(&host->lock);
1035 
1036 	if (pdata)
1037 		dat3_card_detect = pdata->dat3_card_detect;
1038 	else if (mmc_card_is_removable(mmc)
1039 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1040 		dat3_card_detect = true;
1041 
1042 	ret = mmc_regulator_get_supply(mmc);
1043 	if (ret)
1044 		goto out_free;
1045 
1046 	if (!mmc->ocr_avail) {
1047 		if (pdata && pdata->ocr_avail)
1048 			mmc->ocr_avail = pdata->ocr_avail;
1049 		else
1050 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1051 	}
1052 
1053 	if (dat3_card_detect)
1054 		host->default_irq_mask =
1055 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1056 	else
1057 		host->default_irq_mask = 0;
1058 
1059 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1060 	if (IS_ERR(host->clk_ipg)) {
1061 		ret = PTR_ERR(host->clk_ipg);
1062 		goto out_free;
1063 	}
1064 
1065 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1066 	if (IS_ERR(host->clk_per)) {
1067 		ret = PTR_ERR(host->clk_per);
1068 		goto out_free;
1069 	}
1070 
1071 	ret = clk_prepare_enable(host->clk_per);
1072 	if (ret)
1073 		goto out_free;
1074 
1075 	ret = clk_prepare_enable(host->clk_ipg);
1076 	if (ret)
1077 		goto out_clk_per_put;
1078 
1079 	mxcmci_softreset(host);
1080 
1081 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1082 	if (host->rev_no != 0x400) {
1083 		ret = -ENODEV;
1084 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1085 			host->rev_no);
1086 		goto out_clk_put;
1087 	}
1088 
1089 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1090 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1091 
1092 	/* recommended in data sheet */
1093 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1094 
1095 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1096 
1097 	if (!host->pdata) {
1098 		host->dma = dma_request_chan(&pdev->dev, "rx-tx");
1099 		if (IS_ERR(host->dma)) {
1100 			if (PTR_ERR(host->dma) == -EPROBE_DEFER) {
1101 				ret = -EPROBE_DEFER;
1102 				goto out_clk_put;
1103 			}
1104 
1105 			/* Ignore errors to fall back to PIO mode */
1106 			host->dma = NULL;
1107 		}
1108 	} else {
1109 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1110 		if (res) {
1111 			host->dmareq = res->start;
1112 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1113 			host->dma_data.priority = DMA_PRIO_LOW;
1114 			host->dma_data.dma_request = host->dmareq;
1115 			dma_cap_zero(mask);
1116 			dma_cap_set(DMA_SLAVE, mask);
1117 			host->dma = dma_request_channel(mask, filter, host);
1118 		}
1119 	}
1120 	if (host->dma)
1121 		mmc->max_seg_size = dma_get_max_seg_size(
1122 				host->dma->device->dev);
1123 	else
1124 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1125 
1126 	INIT_WORK(&host->datawork, mxcmci_datawork);
1127 
1128 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1129 			       dev_name(&pdev->dev), host);
1130 	if (ret)
1131 		goto out_free_dma;
1132 
1133 	platform_set_drvdata(pdev, mmc);
1134 
1135 	if (host->pdata && host->pdata->init) {
1136 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1137 				host->mmc);
1138 		if (ret)
1139 			goto out_free_dma;
1140 	}
1141 
1142 	timer_setup(&host->watchdog, mxcmci_watchdog, 0);
1143 
1144 	ret = mmc_add_host(mmc);
1145 	if (ret)
1146 		goto out_free_dma;
1147 
1148 	return 0;
1149 
1150 out_free_dma:
1151 	if (host->dma)
1152 		dma_release_channel(host->dma);
1153 
1154 out_clk_put:
1155 	clk_disable_unprepare(host->clk_ipg);
1156 out_clk_per_put:
1157 	clk_disable_unprepare(host->clk_per);
1158 
1159 out_free:
1160 	mmc_free_host(mmc);
1161 
1162 	return ret;
1163 }
1164 
1165 static void mxcmci_remove(struct platform_device *pdev)
1166 {
1167 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1168 	struct mxcmci_host *host = mmc_priv(mmc);
1169 
1170 	mmc_remove_host(mmc);
1171 
1172 	if (host->pdata && host->pdata->exit)
1173 		host->pdata->exit(&pdev->dev, mmc);
1174 
1175 	if (host->dma)
1176 		dma_release_channel(host->dma);
1177 
1178 	clk_disable_unprepare(host->clk_per);
1179 	clk_disable_unprepare(host->clk_ipg);
1180 
1181 	mmc_free_host(mmc);
1182 }
1183 
1184 static int mxcmci_suspend(struct device *dev)
1185 {
1186 	struct mmc_host *mmc = dev_get_drvdata(dev);
1187 	struct mxcmci_host *host = mmc_priv(mmc);
1188 
1189 	clk_disable_unprepare(host->clk_per);
1190 	clk_disable_unprepare(host->clk_ipg);
1191 	return 0;
1192 }
1193 
1194 static int mxcmci_resume(struct device *dev)
1195 {
1196 	struct mmc_host *mmc = dev_get_drvdata(dev);
1197 	struct mxcmci_host *host = mmc_priv(mmc);
1198 	int ret;
1199 
1200 	ret = clk_prepare_enable(host->clk_per);
1201 	if (ret)
1202 		return ret;
1203 
1204 	ret = clk_prepare_enable(host->clk_ipg);
1205 	if (ret)
1206 		clk_disable_unprepare(host->clk_per);
1207 
1208 	return ret;
1209 }
1210 
1211 static DEFINE_SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1212 
1213 static struct platform_driver mxcmci_driver = {
1214 	.probe		= mxcmci_probe,
1215 	.remove_new	= mxcmci_remove,
1216 	.driver		= {
1217 		.name		= DRIVER_NAME,
1218 		.probe_type	= PROBE_PREFER_ASYNCHRONOUS,
1219 		.pm	= pm_sleep_ptr(&mxcmci_pm_ops),
1220 		.of_match_table	= mxcmci_of_match,
1221 	}
1222 };
1223 
1224 module_platform_driver(mxcmci_driver);
1225 
1226 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1227 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1228 MODULE_LICENSE("GPL");
1229 MODULE_ALIAS("platform:mxc-mmc");
1230