xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision e53134fe)
1 /*
2  *  linux/drivers/mmc/host/mxcmmc.c - Freescale i.MX MMCI driver
3  *
4  *  This is a driver for the SDHC controller found in Freescale MX2/MX3
5  *  SoCs. It is basically the same hardware as found on MX1 (imxmmc.c).
6  *  Unlike the hardware found on MX1, this hardware just works and does
7  *  not need all the quirks found in imxmmc.c, hence the separate driver.
8  *
9  *  Copyright (C) 2008 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
10  *  Copyright (C) 2006 Pavel Pisa, PiKRON <ppisa@pikron.com>
11  *
12  *  derived from pxamci.c by Russell King
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License version 2 as
16  * published by the Free Software Foundation.
17  *
18  */
19 
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/ioport.h>
23 #include <linux/platform_device.h>
24 #include <linux/highmem.h>
25 #include <linux/interrupt.h>
26 #include <linux/irq.h>
27 #include <linux/blkdev.h>
28 #include <linux/dma-mapping.h>
29 #include <linux/mmc/host.h>
30 #include <linux/mmc/card.h>
31 #include <linux/delay.h>
32 #include <linux/clk.h>
33 #include <linux/io.h>
34 #include <linux/gpio.h>
35 #include <linux/regulator/consumer.h>
36 #include <linux/dmaengine.h>
37 #include <linux/types.h>
38 #include <linux/of.h>
39 #include <linux/of_device.h>
40 #include <linux/of_dma.h>
41 #include <linux/of_gpio.h>
42 #include <linux/mmc/slot-gpio.h>
43 
44 #include <asm/dma.h>
45 #include <asm/irq.h>
46 #include <linux/platform_data/mmc-mxcmmc.h>
47 
48 #include <linux/platform_data/dma-imx.h>
49 
50 #define DRIVER_NAME "mxc-mmc"
51 #define MXCMCI_TIMEOUT_MS 10000
52 
53 #define MMC_REG_STR_STP_CLK		0x00
54 #define MMC_REG_STATUS			0x04
55 #define MMC_REG_CLK_RATE		0x08
56 #define MMC_REG_CMD_DAT_CONT		0x0C
57 #define MMC_REG_RES_TO			0x10
58 #define MMC_REG_READ_TO			0x14
59 #define MMC_REG_BLK_LEN			0x18
60 #define MMC_REG_NOB			0x1C
61 #define MMC_REG_REV_NO			0x20
62 #define MMC_REG_INT_CNTR		0x24
63 #define MMC_REG_CMD			0x28
64 #define MMC_REG_ARG			0x2C
65 #define MMC_REG_RES_FIFO		0x34
66 #define MMC_REG_BUFFER_ACCESS		0x38
67 
68 #define STR_STP_CLK_RESET               (1 << 3)
69 #define STR_STP_CLK_START_CLK           (1 << 1)
70 #define STR_STP_CLK_STOP_CLK            (1 << 0)
71 
72 #define STATUS_CARD_INSERTION		(1 << 31)
73 #define STATUS_CARD_REMOVAL		(1 << 30)
74 #define STATUS_YBUF_EMPTY		(1 << 29)
75 #define STATUS_XBUF_EMPTY		(1 << 28)
76 #define STATUS_YBUF_FULL		(1 << 27)
77 #define STATUS_XBUF_FULL		(1 << 26)
78 #define STATUS_BUF_UND_RUN		(1 << 25)
79 #define STATUS_BUF_OVFL			(1 << 24)
80 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
81 #define STATUS_END_CMD_RESP		(1 << 13)
82 #define STATUS_WRITE_OP_DONE		(1 << 12)
83 #define STATUS_DATA_TRANS_DONE		(1 << 11)
84 #define STATUS_READ_OP_DONE		(1 << 11)
85 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
86 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
87 #define STATUS_BUF_READ_RDY		(1 << 7)
88 #define STATUS_BUF_WRITE_RDY		(1 << 6)
89 #define STATUS_RESP_CRC_ERR		(1 << 5)
90 #define STATUS_CRC_READ_ERR		(1 << 3)
91 #define STATUS_CRC_WRITE_ERR		(1 << 2)
92 #define STATUS_TIME_OUT_RESP		(1 << 1)
93 #define STATUS_TIME_OUT_READ		(1 << 0)
94 #define STATUS_ERR_MASK			0x2f
95 
96 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
97 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
98 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
99 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
100 #define CMD_DAT_CONT_INIT		(1 << 7)
101 #define CMD_DAT_CONT_WRITE		(1 << 4)
102 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
103 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
104 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
105 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
106 
107 #define INT_SDIO_INT_WKP_EN		(1 << 18)
108 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
109 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
110 #define INT_CARD_INSERTION_EN		(1 << 15)
111 #define INT_CARD_REMOVAL_EN		(1 << 14)
112 #define INT_SDIO_IRQ_EN			(1 << 13)
113 #define INT_DAT0_EN			(1 << 12)
114 #define INT_BUF_READ_EN			(1 << 4)
115 #define INT_BUF_WRITE_EN		(1 << 3)
116 #define INT_END_CMD_RES_EN		(1 << 2)
117 #define INT_WRITE_OP_DONE_EN		(1 << 1)
118 #define INT_READ_OP_EN			(1 << 0)
119 
120 enum mxcmci_type {
121 	IMX21_MMC,
122 	IMX31_MMC,
123 	MPC512X_MMC,
124 };
125 
126 struct mxcmci_host {
127 	struct mmc_host		*mmc;
128 	void __iomem		*base;
129 	dma_addr_t		phys_base;
130 	int			detect_irq;
131 	struct dma_chan		*dma;
132 	struct dma_async_tx_descriptor *desc;
133 	int			do_dma;
134 	int			default_irq_mask;
135 	int			use_sdio;
136 	unsigned int		power_mode;
137 	struct imxmmc_platform_data *pdata;
138 
139 	struct mmc_request	*req;
140 	struct mmc_command	*cmd;
141 	struct mmc_data		*data;
142 
143 	unsigned int		datasize;
144 	unsigned int		dma_dir;
145 
146 	u16			rev_no;
147 	unsigned int		cmdat;
148 
149 	struct clk		*clk_ipg;
150 	struct clk		*clk_per;
151 
152 	int			clock;
153 
154 	struct work_struct	datawork;
155 	spinlock_t		lock;
156 
157 	int			burstlen;
158 	int			dmareq;
159 	struct dma_slave_config dma_slave_config;
160 	struct imx_dma_data	dma_data;
161 
162 	struct timer_list	watchdog;
163 	enum mxcmci_type	devtype;
164 };
165 
166 static const struct platform_device_id mxcmci_devtype[] = {
167 	{
168 		.name = "imx21-mmc",
169 		.driver_data = IMX21_MMC,
170 	}, {
171 		.name = "imx31-mmc",
172 		.driver_data = IMX31_MMC,
173 	}, {
174 		.name = "mpc512x-sdhc",
175 		.driver_data = MPC512X_MMC,
176 	}, {
177 		/* sentinel */
178 	}
179 };
180 MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
181 
182 static const struct of_device_id mxcmci_of_match[] = {
183 	{
184 		.compatible = "fsl,imx21-mmc",
185 		.data = &mxcmci_devtype[IMX21_MMC],
186 	}, {
187 		.compatible = "fsl,imx31-mmc",
188 		.data = &mxcmci_devtype[IMX31_MMC],
189 	}, {
190 		.compatible = "fsl,mpc5121-sdhc",
191 		.data = &mxcmci_devtype[MPC512X_MMC],
192 	}, {
193 		/* sentinel */
194 	}
195 };
196 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
197 
198 static inline int is_imx31_mmc(struct mxcmci_host *host)
199 {
200 	return host->devtype == IMX31_MMC;
201 }
202 
203 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
204 {
205 	return host->devtype == MPC512X_MMC;
206 }
207 
208 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
209 {
210 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
211 		return ioread32be(host->base + reg);
212 	else
213 		return readl(host->base + reg);
214 }
215 
216 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
217 {
218 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
219 		iowrite32be(val, host->base + reg);
220 	else
221 		writel(val, host->base + reg);
222 }
223 
224 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
225 {
226 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
227 		return ioread32be(host->base + reg);
228 	else
229 		return readw(host->base + reg);
230 }
231 
232 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
233 {
234 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
235 		iowrite32be(val, host->base + reg);
236 	else
237 		writew(val, host->base + reg);
238 }
239 
240 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
241 
242 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
243 {
244 	if (!IS_ERR(host->mmc->supply.vmmc)) {
245 		if (host->power_mode == MMC_POWER_UP)
246 			mmc_regulator_set_ocr(host->mmc,
247 					      host->mmc->supply.vmmc, vdd);
248 		else if (host->power_mode == MMC_POWER_OFF)
249 			mmc_regulator_set_ocr(host->mmc,
250 					      host->mmc->supply.vmmc, 0);
251 	}
252 
253 	if (host->pdata && host->pdata->setpower)
254 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
255 }
256 
257 static inline int mxcmci_use_dma(struct mxcmci_host *host)
258 {
259 	return host->do_dma;
260 }
261 
262 static void mxcmci_softreset(struct mxcmci_host *host)
263 {
264 	int i;
265 
266 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
267 
268 	/* reset sequence */
269 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
270 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
271 			MMC_REG_STR_STP_CLK);
272 
273 	for (i = 0; i < 8; i++)
274 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
275 
276 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
277 }
278 
279 #if IS_ENABLED(CONFIG_PPC_MPC512x)
280 static inline void buffer_swap32(u32 *buf, int len)
281 {
282 	int i;
283 
284 	for (i = 0; i < ((len + 3) / 4); i++) {
285 		*buf = swab32(*buf);
286 		buf++;
287 	}
288 }
289 
290 static void mxcmci_swap_buffers(struct mmc_data *data)
291 {
292 	struct scatterlist *sg;
293 	int i;
294 
295 	for_each_sg(data->sg, sg, data->sg_len, i) {
296 		void *buf = kmap_atomic(sg_page(sg) + sg->offset);
297 		buffer_swap32(buf, sg->length);
298 		kunmap_atomic(buf);
299 	}
300 }
301 #else
302 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
303 #endif
304 
305 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
306 {
307 	unsigned int nob = data->blocks;
308 	unsigned int blksz = data->blksz;
309 	unsigned int datasize = nob * blksz;
310 	struct scatterlist *sg;
311 	enum dma_transfer_direction slave_dirn;
312 	int i, nents;
313 
314 	host->data = data;
315 	data->bytes_xfered = 0;
316 
317 	mxcmci_writew(host, nob, MMC_REG_NOB);
318 	mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
319 	host->datasize = datasize;
320 
321 	if (!mxcmci_use_dma(host))
322 		return 0;
323 
324 	for_each_sg(data->sg, sg, data->sg_len, i) {
325 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
326 			host->do_dma = 0;
327 			return 0;
328 		}
329 	}
330 
331 	if (data->flags & MMC_DATA_READ) {
332 		host->dma_dir = DMA_FROM_DEVICE;
333 		slave_dirn = DMA_DEV_TO_MEM;
334 	} else {
335 		host->dma_dir = DMA_TO_DEVICE;
336 		slave_dirn = DMA_MEM_TO_DEV;
337 
338 		mxcmci_swap_buffers(data);
339 	}
340 
341 	nents = dma_map_sg(host->dma->device->dev, data->sg,
342 				     data->sg_len,  host->dma_dir);
343 	if (nents != data->sg_len)
344 		return -EINVAL;
345 
346 	host->desc = dmaengine_prep_slave_sg(host->dma,
347 		data->sg, data->sg_len, slave_dirn,
348 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
349 
350 	if (!host->desc) {
351 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
352 				host->dma_dir);
353 		host->do_dma = 0;
354 		return 0; /* Fall back to PIO */
355 	}
356 	wmb();
357 
358 	dmaengine_submit(host->desc);
359 	dma_async_issue_pending(host->dma);
360 
361 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
362 
363 	return 0;
364 }
365 
366 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
367 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
368 
369 static void mxcmci_dma_callback(void *data)
370 {
371 	struct mxcmci_host *host = data;
372 	u32 stat;
373 
374 	del_timer(&host->watchdog);
375 
376 	stat = mxcmci_readl(host, MMC_REG_STATUS);
377 
378 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
379 
380 	mxcmci_data_done(host, stat);
381 }
382 
383 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
384 		unsigned int cmdat)
385 {
386 	u32 int_cntr = host->default_irq_mask;
387 	unsigned long flags;
388 
389 	WARN_ON(host->cmd != NULL);
390 	host->cmd = cmd;
391 
392 	switch (mmc_resp_type(cmd)) {
393 	case MMC_RSP_R1: /* short CRC, OPCODE */
394 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
395 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
396 		break;
397 	case MMC_RSP_R2: /* long 136 bit + CRC */
398 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
399 		break;
400 	case MMC_RSP_R3: /* short */
401 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
402 		break;
403 	case MMC_RSP_NONE:
404 		break;
405 	default:
406 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
407 				mmc_resp_type(cmd));
408 		cmd->error = -EINVAL;
409 		return -EINVAL;
410 	}
411 
412 	int_cntr = INT_END_CMD_RES_EN;
413 
414 	if (mxcmci_use_dma(host)) {
415 		if (host->dma_dir == DMA_FROM_DEVICE) {
416 			host->desc->callback = mxcmci_dma_callback;
417 			host->desc->callback_param = host;
418 		} else {
419 			int_cntr |= INT_WRITE_OP_DONE_EN;
420 		}
421 	}
422 
423 	spin_lock_irqsave(&host->lock, flags);
424 	if (host->use_sdio)
425 		int_cntr |= INT_SDIO_IRQ_EN;
426 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
427 	spin_unlock_irqrestore(&host->lock, flags);
428 
429 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
430 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
431 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
432 
433 	return 0;
434 }
435 
436 static void mxcmci_finish_request(struct mxcmci_host *host,
437 		struct mmc_request *req)
438 {
439 	u32 int_cntr = host->default_irq_mask;
440 	unsigned long flags;
441 
442 	spin_lock_irqsave(&host->lock, flags);
443 	if (host->use_sdio)
444 		int_cntr |= INT_SDIO_IRQ_EN;
445 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
446 	spin_unlock_irqrestore(&host->lock, flags);
447 
448 	host->req = NULL;
449 	host->cmd = NULL;
450 	host->data = NULL;
451 
452 	mmc_request_done(host->mmc, req);
453 }
454 
455 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
456 {
457 	struct mmc_data *data = host->data;
458 	int data_error;
459 
460 	if (mxcmci_use_dma(host)) {
461 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
462 				host->dma_dir);
463 		mxcmci_swap_buffers(data);
464 	}
465 
466 	if (stat & STATUS_ERR_MASK) {
467 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
468 				stat);
469 		if (stat & STATUS_CRC_READ_ERR) {
470 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
471 			data->error = -EILSEQ;
472 		} else if (stat & STATUS_CRC_WRITE_ERR) {
473 			u32 err_code = (stat >> 9) & 0x3;
474 			if (err_code == 2) { /* No CRC response */
475 				dev_err(mmc_dev(host->mmc),
476 					"%s: No CRC -ETIMEDOUT\n", __func__);
477 				data->error = -ETIMEDOUT;
478 			} else {
479 				dev_err(mmc_dev(host->mmc),
480 					"%s: -EILSEQ\n", __func__);
481 				data->error = -EILSEQ;
482 			}
483 		} else if (stat & STATUS_TIME_OUT_READ) {
484 			dev_err(mmc_dev(host->mmc),
485 				"%s: read -ETIMEDOUT\n", __func__);
486 			data->error = -ETIMEDOUT;
487 		} else {
488 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
489 			data->error = -EIO;
490 		}
491 	} else {
492 		data->bytes_xfered = host->datasize;
493 	}
494 
495 	data_error = data->error;
496 
497 	host->data = NULL;
498 
499 	return data_error;
500 }
501 
502 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
503 {
504 	struct mmc_command *cmd = host->cmd;
505 	int i;
506 	u32 a, b, c;
507 
508 	if (!cmd)
509 		return;
510 
511 	if (stat & STATUS_TIME_OUT_RESP) {
512 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
513 		cmd->error = -ETIMEDOUT;
514 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
515 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
516 		cmd->error = -EILSEQ;
517 	}
518 
519 	if (cmd->flags & MMC_RSP_PRESENT) {
520 		if (cmd->flags & MMC_RSP_136) {
521 			for (i = 0; i < 4; i++) {
522 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
523 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
524 				cmd->resp[i] = a << 16 | b;
525 			}
526 		} else {
527 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
528 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
529 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
530 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
531 		}
532 	}
533 }
534 
535 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
536 {
537 	u32 stat;
538 	unsigned long timeout = jiffies + HZ;
539 
540 	do {
541 		stat = mxcmci_readl(host, MMC_REG_STATUS);
542 		if (stat & STATUS_ERR_MASK)
543 			return stat;
544 		if (time_after(jiffies, timeout)) {
545 			mxcmci_softreset(host);
546 			mxcmci_set_clk_rate(host, host->clock);
547 			return STATUS_TIME_OUT_READ;
548 		}
549 		if (stat & mask)
550 			return 0;
551 		cpu_relax();
552 	} while (1);
553 }
554 
555 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
556 {
557 	unsigned int stat;
558 	u32 *buf = _buf;
559 
560 	while (bytes > 3) {
561 		stat = mxcmci_poll_status(host,
562 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
563 		if (stat)
564 			return stat;
565 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
566 		bytes -= 4;
567 	}
568 
569 	if (bytes) {
570 		u8 *b = (u8 *)buf;
571 		u32 tmp;
572 
573 		stat = mxcmci_poll_status(host,
574 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
575 		if (stat)
576 			return stat;
577 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
578 		memcpy(b, &tmp, bytes);
579 	}
580 
581 	return 0;
582 }
583 
584 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
585 {
586 	unsigned int stat;
587 	u32 *buf = _buf;
588 
589 	while (bytes > 3) {
590 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
591 		if (stat)
592 			return stat;
593 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
594 		bytes -= 4;
595 	}
596 
597 	if (bytes) {
598 		u8 *b = (u8 *)buf;
599 		u32 tmp;
600 
601 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
602 		if (stat)
603 			return stat;
604 
605 		memcpy(&tmp, b, bytes);
606 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
607 	}
608 
609 	return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
610 }
611 
612 static int mxcmci_transfer_data(struct mxcmci_host *host)
613 {
614 	struct mmc_data *data = host->req->data;
615 	struct scatterlist *sg;
616 	void *buf;
617 	int stat, i;
618 
619 	host->data = data;
620 	host->datasize = 0;
621 
622 	if (data->flags & MMC_DATA_READ) {
623 		for_each_sg(data->sg, sg, data->sg_len, i) {
624 			buf = kmap_atomic(sg_page(sg) + sg->offset);
625 			stat = mxcmci_pull(host, buf, sg->length);
626 			kunmap(buf);
627 			if (stat)
628 				return stat;
629 			host->datasize += sg->length;
630 		}
631 	} else {
632 		for_each_sg(data->sg, sg, data->sg_len, i) {
633 			buf = kmap_atomic(sg_page(sg) + sg->offset);
634 			stat = mxcmci_push(host, buf, sg->length);
635 			kunmap(buf);
636 			if (stat)
637 				return stat;
638 			host->datasize += sg->length;
639 		}
640 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
641 		if (stat)
642 			return stat;
643 	}
644 	return 0;
645 }
646 
647 static void mxcmci_datawork(struct work_struct *work)
648 {
649 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
650 						  datawork);
651 	int datastat = mxcmci_transfer_data(host);
652 
653 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
654 		MMC_REG_STATUS);
655 	mxcmci_finish_data(host, datastat);
656 
657 	if (host->req->stop) {
658 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
659 			mxcmci_finish_request(host, host->req);
660 			return;
661 		}
662 	} else {
663 		mxcmci_finish_request(host, host->req);
664 	}
665 }
666 
667 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
668 {
669 	struct mmc_request *req;
670 	int data_error;
671 	unsigned long flags;
672 
673 	spin_lock_irqsave(&host->lock, flags);
674 
675 	if (!host->data) {
676 		spin_unlock_irqrestore(&host->lock, flags);
677 		return;
678 	}
679 
680 	if (!host->req) {
681 		spin_unlock_irqrestore(&host->lock, flags);
682 		return;
683 	}
684 
685 	req = host->req;
686 	if (!req->stop)
687 		host->req = NULL; /* we will handle finish req below */
688 
689 	data_error = mxcmci_finish_data(host, stat);
690 
691 	spin_unlock_irqrestore(&host->lock, flags);
692 
693 	if (data_error)
694 		return;
695 
696 	mxcmci_read_response(host, stat);
697 	host->cmd = NULL;
698 
699 	if (req->stop) {
700 		if (mxcmci_start_cmd(host, req->stop, 0)) {
701 			mxcmci_finish_request(host, req);
702 			return;
703 		}
704 	} else {
705 		mxcmci_finish_request(host, req);
706 	}
707 }
708 
709 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
710 {
711 	mxcmci_read_response(host, stat);
712 	host->cmd = NULL;
713 
714 	if (!host->data && host->req) {
715 		mxcmci_finish_request(host, host->req);
716 		return;
717 	}
718 
719 	/* For the DMA case the DMA engine handles the data transfer
720 	 * automatically. For non DMA we have to do it ourselves.
721 	 * Don't do it in interrupt context though.
722 	 */
723 	if (!mxcmci_use_dma(host) && host->data)
724 		schedule_work(&host->datawork);
725 
726 }
727 
728 static irqreturn_t mxcmci_irq(int irq, void *devid)
729 {
730 	struct mxcmci_host *host = devid;
731 	unsigned long flags;
732 	bool sdio_irq;
733 	u32 stat;
734 
735 	stat = mxcmci_readl(host, MMC_REG_STATUS);
736 	mxcmci_writel(host,
737 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
738 			 STATUS_WRITE_OP_DONE),
739 		MMC_REG_STATUS);
740 
741 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
742 
743 	spin_lock_irqsave(&host->lock, flags);
744 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
745 	spin_unlock_irqrestore(&host->lock, flags);
746 
747 	if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
748 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
749 
750 	if (sdio_irq) {
751 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
752 		mmc_signal_sdio_irq(host->mmc);
753 	}
754 
755 	if (stat & STATUS_END_CMD_RESP)
756 		mxcmci_cmd_done(host, stat);
757 
758 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
759 		del_timer(&host->watchdog);
760 		mxcmci_data_done(host, stat);
761 	}
762 
763 	if (host->default_irq_mask &&
764 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
765 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
766 
767 	return IRQ_HANDLED;
768 }
769 
770 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
771 {
772 	struct mxcmci_host *host = mmc_priv(mmc);
773 	unsigned int cmdat = host->cmdat;
774 	int error;
775 
776 	WARN_ON(host->req != NULL);
777 
778 	host->req = req;
779 	host->cmdat &= ~CMD_DAT_CONT_INIT;
780 
781 	if (host->dma)
782 		host->do_dma = 1;
783 
784 	if (req->data) {
785 		error = mxcmci_setup_data(host, req->data);
786 		if (error) {
787 			req->cmd->error = error;
788 			goto out;
789 		}
790 
791 
792 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
793 
794 		if (req->data->flags & MMC_DATA_WRITE)
795 			cmdat |= CMD_DAT_CONT_WRITE;
796 	}
797 
798 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
799 
800 out:
801 	if (error)
802 		mxcmci_finish_request(host, req);
803 }
804 
805 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
806 {
807 	unsigned int divider;
808 	int prescaler = 0;
809 	unsigned int clk_in = clk_get_rate(host->clk_per);
810 
811 	while (prescaler <= 0x800) {
812 		for (divider = 1; divider <= 0xF; divider++) {
813 			int x;
814 
815 			x = (clk_in / (divider + 1));
816 
817 			if (prescaler)
818 				x /= (prescaler * 2);
819 
820 			if (x <= clk_ios)
821 				break;
822 		}
823 		if (divider < 0x10)
824 			break;
825 
826 		if (prescaler == 0)
827 			prescaler = 1;
828 		else
829 			prescaler <<= 1;
830 	}
831 
832 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
833 
834 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
835 			prescaler, divider, clk_in, clk_ios);
836 }
837 
838 static int mxcmci_setup_dma(struct mmc_host *mmc)
839 {
840 	struct mxcmci_host *host = mmc_priv(mmc);
841 	struct dma_slave_config *config = &host->dma_slave_config;
842 
843 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
844 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
845 	config->dst_addr_width = 4;
846 	config->src_addr_width = 4;
847 	config->dst_maxburst = host->burstlen;
848 	config->src_maxburst = host->burstlen;
849 	config->device_fc = false;
850 
851 	return dmaengine_slave_config(host->dma, config);
852 }
853 
854 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
855 {
856 	struct mxcmci_host *host = mmc_priv(mmc);
857 	int burstlen, ret;
858 
859 	/*
860 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
861 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
862 	 */
863 	if (ios->bus_width == MMC_BUS_WIDTH_4)
864 		burstlen = 16;
865 	else
866 		burstlen = 4;
867 
868 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
869 		host->burstlen = burstlen;
870 		ret = mxcmci_setup_dma(mmc);
871 		if (ret) {
872 			dev_err(mmc_dev(host->mmc),
873 				"failed to config DMA channel. Falling back to PIO\n");
874 			dma_release_channel(host->dma);
875 			host->do_dma = 0;
876 			host->dma = NULL;
877 		}
878 	}
879 
880 	if (ios->bus_width == MMC_BUS_WIDTH_4)
881 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
882 	else
883 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
884 
885 	if (host->power_mode != ios->power_mode) {
886 		host->power_mode = ios->power_mode;
887 		mxcmci_set_power(host, ios->vdd);
888 
889 		if (ios->power_mode == MMC_POWER_ON)
890 			host->cmdat |= CMD_DAT_CONT_INIT;
891 	}
892 
893 	if (ios->clock) {
894 		mxcmci_set_clk_rate(host, ios->clock);
895 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
896 	} else {
897 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
898 	}
899 
900 	host->clock = ios->clock;
901 }
902 
903 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
904 {
905 	struct mmc_host *mmc = data;
906 
907 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
908 
909 	mmc_detect_change(mmc, msecs_to_jiffies(250));
910 	return IRQ_HANDLED;
911 }
912 
913 static int mxcmci_get_ro(struct mmc_host *mmc)
914 {
915 	struct mxcmci_host *host = mmc_priv(mmc);
916 
917 	if (host->pdata && host->pdata->get_ro)
918 		return !!host->pdata->get_ro(mmc_dev(mmc));
919 	/*
920 	 * If board doesn't support read only detection (no mmc_gpio
921 	 * context or gpio is invalid), then let the mmc core decide
922 	 * what to do.
923 	 */
924 	return mmc_gpio_get_ro(mmc);
925 }
926 
927 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
928 {
929 	struct mxcmci_host *host = mmc_priv(mmc);
930 	unsigned long flags;
931 	u32 int_cntr;
932 
933 	spin_lock_irqsave(&host->lock, flags);
934 	host->use_sdio = enable;
935 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
936 
937 	if (enable)
938 		int_cntr |= INT_SDIO_IRQ_EN;
939 	else
940 		int_cntr &= ~INT_SDIO_IRQ_EN;
941 
942 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
943 	spin_unlock_irqrestore(&host->lock, flags);
944 }
945 
946 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
947 {
948 	struct mxcmci_host *mxcmci = mmc_priv(host);
949 
950 	/*
951 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
952 	 * multi-block transfers when connected SDIO peripheral doesn't
953 	 * drive the BUSY line as required by the specs.
954 	 * One way to prevent this is to only allow 1-bit transfers.
955 	 */
956 
957 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
958 		host->caps &= ~MMC_CAP_4_BIT_DATA;
959 	else
960 		host->caps |= MMC_CAP_4_BIT_DATA;
961 }
962 
963 static bool filter(struct dma_chan *chan, void *param)
964 {
965 	struct mxcmci_host *host = param;
966 
967 	if (!imx_dma_is_general_purpose(chan))
968 		return false;
969 
970 	chan->private = &host->dma_data;
971 
972 	return true;
973 }
974 
975 static void mxcmci_watchdog(struct timer_list *t)
976 {
977 	struct mxcmci_host *host = from_timer(host, t, watchdog);
978 	struct mmc_request *req = host->req;
979 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
980 
981 	if (host->dma_dir == DMA_FROM_DEVICE) {
982 		dmaengine_terminate_all(host->dma);
983 		dev_err(mmc_dev(host->mmc),
984 			"%s: read time out (status = 0x%08x)\n",
985 			__func__, stat);
986 	} else {
987 		dev_err(mmc_dev(host->mmc),
988 			"%s: write time out (status = 0x%08x)\n",
989 			__func__, stat);
990 		mxcmci_softreset(host);
991 	}
992 
993 	/* Mark transfer as erroneus and inform the upper layers */
994 
995 	if (host->data)
996 		host->data->error = -ETIMEDOUT;
997 	host->req = NULL;
998 	host->cmd = NULL;
999 	host->data = NULL;
1000 	mmc_request_done(host->mmc, req);
1001 }
1002 
1003 static const struct mmc_host_ops mxcmci_ops = {
1004 	.request		= mxcmci_request,
1005 	.set_ios		= mxcmci_set_ios,
1006 	.get_ro			= mxcmci_get_ro,
1007 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
1008 	.init_card		= mxcmci_init_card,
1009 };
1010 
1011 static int mxcmci_probe(struct platform_device *pdev)
1012 {
1013 	struct mmc_host *mmc;
1014 	struct mxcmci_host *host;
1015 	struct resource *res;
1016 	int ret = 0, irq;
1017 	bool dat3_card_detect = false;
1018 	dma_cap_mask_t mask;
1019 	const struct of_device_id *of_id;
1020 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
1021 
1022 	pr_info("i.MX/MPC512x SDHC driver\n");
1023 
1024 	of_id = of_match_device(mxcmci_of_match, &pdev->dev);
1025 
1026 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1027 	irq = platform_get_irq(pdev, 0);
1028 	if (irq < 0) {
1029 		dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
1030 		return irq;
1031 	}
1032 
1033 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1034 	if (!mmc)
1035 		return -ENOMEM;
1036 
1037 	host = mmc_priv(mmc);
1038 
1039 	host->base = devm_ioremap_resource(&pdev->dev, res);
1040 	if (IS_ERR(host->base)) {
1041 		ret = PTR_ERR(host->base);
1042 		goto out_free;
1043 	}
1044 
1045 	host->phys_base = res->start;
1046 
1047 	ret = mmc_of_parse(mmc);
1048 	if (ret)
1049 		goto out_free;
1050 	mmc->ops = &mxcmci_ops;
1051 
1052 	/* For devicetree parsing, the bus width is read from devicetree */
1053 	if (pdata)
1054 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1055 	else
1056 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1057 
1058 	/* MMC core transfer sizes tunable parameters */
1059 	mmc->max_blk_size = 2048;
1060 	mmc->max_blk_count = 65535;
1061 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1062 	mmc->max_seg_size = mmc->max_req_size;
1063 
1064 	if (of_id) {
1065 		const struct platform_device_id *id_entry = of_id->data;
1066 		host->devtype = id_entry->driver_data;
1067 	} else {
1068 		host->devtype = pdev->id_entry->driver_data;
1069 	}
1070 
1071 	/* adjust max_segs after devtype detection */
1072 	if (!is_mpc512x_mmc(host))
1073 		mmc->max_segs = 64;
1074 
1075 	host->mmc = mmc;
1076 	host->pdata = pdata;
1077 	spin_lock_init(&host->lock);
1078 
1079 	if (pdata)
1080 		dat3_card_detect = pdata->dat3_card_detect;
1081 	else if (mmc_card_is_removable(mmc)
1082 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1083 		dat3_card_detect = true;
1084 
1085 	ret = mmc_regulator_get_supply(mmc);
1086 	if (ret)
1087 		goto out_free;
1088 
1089 	if (!mmc->ocr_avail) {
1090 		if (pdata && pdata->ocr_avail)
1091 			mmc->ocr_avail = pdata->ocr_avail;
1092 		else
1093 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1094 	}
1095 
1096 	if (dat3_card_detect)
1097 		host->default_irq_mask =
1098 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1099 	else
1100 		host->default_irq_mask = 0;
1101 
1102 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1103 	if (IS_ERR(host->clk_ipg)) {
1104 		ret = PTR_ERR(host->clk_ipg);
1105 		goto out_free;
1106 	}
1107 
1108 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1109 	if (IS_ERR(host->clk_per)) {
1110 		ret = PTR_ERR(host->clk_per);
1111 		goto out_free;
1112 	}
1113 
1114 	ret = clk_prepare_enable(host->clk_per);
1115 	if (ret)
1116 		goto out_free;
1117 
1118 	ret = clk_prepare_enable(host->clk_ipg);
1119 	if (ret)
1120 		goto out_clk_per_put;
1121 
1122 	mxcmci_softreset(host);
1123 
1124 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1125 	if (host->rev_no != 0x400) {
1126 		ret = -ENODEV;
1127 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1128 			host->rev_no);
1129 		goto out_clk_put;
1130 	}
1131 
1132 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1133 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1134 
1135 	/* recommended in data sheet */
1136 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1137 
1138 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1139 
1140 	if (!host->pdata) {
1141 		host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
1142 	} else {
1143 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1144 		if (res) {
1145 			host->dmareq = res->start;
1146 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1147 			host->dma_data.priority = DMA_PRIO_LOW;
1148 			host->dma_data.dma_request = host->dmareq;
1149 			dma_cap_zero(mask);
1150 			dma_cap_set(DMA_SLAVE, mask);
1151 			host->dma = dma_request_channel(mask, filter, host);
1152 		}
1153 	}
1154 	if (host->dma)
1155 		mmc->max_seg_size = dma_get_max_seg_size(
1156 				host->dma->device->dev);
1157 	else
1158 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1159 
1160 	INIT_WORK(&host->datawork, mxcmci_datawork);
1161 
1162 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1163 			       dev_name(&pdev->dev), host);
1164 	if (ret)
1165 		goto out_free_dma;
1166 
1167 	platform_set_drvdata(pdev, mmc);
1168 
1169 	if (host->pdata && host->pdata->init) {
1170 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1171 				host->mmc);
1172 		if (ret)
1173 			goto out_free_dma;
1174 	}
1175 
1176 	timer_setup(&host->watchdog, mxcmci_watchdog, 0);
1177 
1178 	mmc_add_host(mmc);
1179 
1180 	return 0;
1181 
1182 out_free_dma:
1183 	if (host->dma)
1184 		dma_release_channel(host->dma);
1185 
1186 out_clk_put:
1187 	clk_disable_unprepare(host->clk_ipg);
1188 out_clk_per_put:
1189 	clk_disable_unprepare(host->clk_per);
1190 
1191 out_free:
1192 	mmc_free_host(mmc);
1193 
1194 	return ret;
1195 }
1196 
1197 static int mxcmci_remove(struct platform_device *pdev)
1198 {
1199 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1200 	struct mxcmci_host *host = mmc_priv(mmc);
1201 
1202 	mmc_remove_host(mmc);
1203 
1204 	if (host->pdata && host->pdata->exit)
1205 		host->pdata->exit(&pdev->dev, mmc);
1206 
1207 	if (host->dma)
1208 		dma_release_channel(host->dma);
1209 
1210 	clk_disable_unprepare(host->clk_per);
1211 	clk_disable_unprepare(host->clk_ipg);
1212 
1213 	mmc_free_host(mmc);
1214 
1215 	return 0;
1216 }
1217 
1218 #ifdef CONFIG_PM_SLEEP
1219 static int mxcmci_suspend(struct device *dev)
1220 {
1221 	struct mmc_host *mmc = dev_get_drvdata(dev);
1222 	struct mxcmci_host *host = mmc_priv(mmc);
1223 
1224 	clk_disable_unprepare(host->clk_per);
1225 	clk_disable_unprepare(host->clk_ipg);
1226 	return 0;
1227 }
1228 
1229 static int mxcmci_resume(struct device *dev)
1230 {
1231 	struct mmc_host *mmc = dev_get_drvdata(dev);
1232 	struct mxcmci_host *host = mmc_priv(mmc);
1233 	int ret;
1234 
1235 	ret = clk_prepare_enable(host->clk_per);
1236 	if (ret)
1237 		return ret;
1238 
1239 	ret = clk_prepare_enable(host->clk_ipg);
1240 	if (ret)
1241 		clk_disable_unprepare(host->clk_per);
1242 
1243 	return ret;
1244 }
1245 #endif
1246 
1247 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1248 
1249 static struct platform_driver mxcmci_driver = {
1250 	.probe		= mxcmci_probe,
1251 	.remove		= mxcmci_remove,
1252 	.id_table	= mxcmci_devtype,
1253 	.driver		= {
1254 		.name		= DRIVER_NAME,
1255 		.pm	= &mxcmci_pm_ops,
1256 		.of_match_table	= mxcmci_of_match,
1257 	}
1258 };
1259 
1260 module_platform_driver(mxcmci_driver);
1261 
1262 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1263 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1264 MODULE_LICENSE("GPL");
1265 MODULE_ALIAS("platform:mxc-mmc");
1266