xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision b189e758)
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/interrupt.h>
25 #include <linux/irq.h>
26 #include <linux/blkdev.h>
27 #include <linux/dma-mapping.h>
28 #include <linux/mmc/host.h>
29 #include <linux/mmc/card.h>
30 #include <linux/delay.h>
31 #include <linux/clk.h>
32 #include <linux/io.h>
33 #include <linux/gpio.h>
34 #include <linux/regulator/consumer.h>
35 #include <linux/dmaengine.h>
36 #include <linux/types.h>
37 #include <linux/of.h>
38 #include <linux/of_device.h>
39 #include <linux/of_dma.h>
40 #include <linux/of_gpio.h>
41 #include <linux/mmc/slot-gpio.h>
42 
43 #include <asm/dma.h>
44 #include <asm/irq.h>
45 #include <linux/platform_data/mmc-mxcmmc.h>
46 
47 #include <linux/platform_data/dma-imx.h>
48 
49 #define DRIVER_NAME "mxc-mmc"
50 #define MXCMCI_TIMEOUT_MS 10000
51 
52 #define MMC_REG_STR_STP_CLK		0x00
53 #define MMC_REG_STATUS			0x04
54 #define MMC_REG_CLK_RATE		0x08
55 #define MMC_REG_CMD_DAT_CONT		0x0C
56 #define MMC_REG_RES_TO			0x10
57 #define MMC_REG_READ_TO			0x14
58 #define MMC_REG_BLK_LEN			0x18
59 #define MMC_REG_NOB			0x1C
60 #define MMC_REG_REV_NO			0x20
61 #define MMC_REG_INT_CNTR		0x24
62 #define MMC_REG_CMD			0x28
63 #define MMC_REG_ARG			0x2C
64 #define MMC_REG_RES_FIFO		0x34
65 #define MMC_REG_BUFFER_ACCESS		0x38
66 
67 #define STR_STP_CLK_RESET               (1 << 3)
68 #define STR_STP_CLK_START_CLK           (1 << 1)
69 #define STR_STP_CLK_STOP_CLK            (1 << 0)
70 
71 #define STATUS_CARD_INSERTION		(1 << 31)
72 #define STATUS_CARD_REMOVAL		(1 << 30)
73 #define STATUS_YBUF_EMPTY		(1 << 29)
74 #define STATUS_XBUF_EMPTY		(1 << 28)
75 #define STATUS_YBUF_FULL		(1 << 27)
76 #define STATUS_XBUF_FULL		(1 << 26)
77 #define STATUS_BUF_UND_RUN		(1 << 25)
78 #define STATUS_BUF_OVFL			(1 << 24)
79 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
80 #define STATUS_END_CMD_RESP		(1 << 13)
81 #define STATUS_WRITE_OP_DONE		(1 << 12)
82 #define STATUS_DATA_TRANS_DONE		(1 << 11)
83 #define STATUS_READ_OP_DONE		(1 << 11)
84 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
85 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
86 #define STATUS_BUF_READ_RDY		(1 << 7)
87 #define STATUS_BUF_WRITE_RDY		(1 << 6)
88 #define STATUS_RESP_CRC_ERR		(1 << 5)
89 #define STATUS_CRC_READ_ERR		(1 << 3)
90 #define STATUS_CRC_WRITE_ERR		(1 << 2)
91 #define STATUS_TIME_OUT_RESP		(1 << 1)
92 #define STATUS_TIME_OUT_READ		(1 << 0)
93 #define STATUS_ERR_MASK			0x2f
94 
95 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
96 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
97 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
98 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
99 #define CMD_DAT_CONT_INIT		(1 << 7)
100 #define CMD_DAT_CONT_WRITE		(1 << 4)
101 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
102 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
103 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
104 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
105 
106 #define INT_SDIO_INT_WKP_EN		(1 << 18)
107 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
108 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
109 #define INT_CARD_INSERTION_EN		(1 << 15)
110 #define INT_CARD_REMOVAL_EN		(1 << 14)
111 #define INT_SDIO_IRQ_EN			(1 << 13)
112 #define INT_DAT0_EN			(1 << 12)
113 #define INT_BUF_READ_EN			(1 << 4)
114 #define INT_BUF_WRITE_EN		(1 << 3)
115 #define INT_END_CMD_RES_EN		(1 << 2)
116 #define INT_WRITE_OP_DONE_EN		(1 << 1)
117 #define INT_READ_OP_EN			(1 << 0)
118 
119 enum mxcmci_type {
120 	IMX21_MMC,
121 	IMX31_MMC,
122 	MPC512X_MMC,
123 };
124 
125 struct mxcmci_host {
126 	struct mmc_host		*mmc;
127 	void __iomem		*base;
128 	dma_addr_t		phys_base;
129 	int			detect_irq;
130 	struct dma_chan		*dma;
131 	struct dma_async_tx_descriptor *desc;
132 	int			do_dma;
133 	int			default_irq_mask;
134 	int			use_sdio;
135 	unsigned int		power_mode;
136 	struct imxmmc_platform_data *pdata;
137 
138 	struct mmc_request	*req;
139 	struct mmc_command	*cmd;
140 	struct mmc_data		*data;
141 
142 	unsigned int		datasize;
143 	unsigned int		dma_dir;
144 
145 	u16			rev_no;
146 	unsigned int		cmdat;
147 
148 	struct clk		*clk_ipg;
149 	struct clk		*clk_per;
150 
151 	int			clock;
152 
153 	struct work_struct	datawork;
154 	spinlock_t		lock;
155 
156 	int			burstlen;
157 	int			dmareq;
158 	struct dma_slave_config dma_slave_config;
159 	struct imx_dma_data	dma_data;
160 
161 	struct timer_list	watchdog;
162 	enum mxcmci_type	devtype;
163 };
164 
165 static const struct platform_device_id mxcmci_devtype[] = {
166 	{
167 		.name = "imx21-mmc",
168 		.driver_data = IMX21_MMC,
169 	}, {
170 		.name = "imx31-mmc",
171 		.driver_data = IMX31_MMC,
172 	}, {
173 		.name = "mpc512x-sdhc",
174 		.driver_data = MPC512X_MMC,
175 	}, {
176 		/* sentinel */
177 	}
178 };
179 MODULE_DEVICE_TABLE(platform, mxcmci_devtype);
180 
181 static const struct of_device_id mxcmci_of_match[] = {
182 	{
183 		.compatible = "fsl,imx21-mmc",
184 		.data = &mxcmci_devtype[IMX21_MMC],
185 	}, {
186 		.compatible = "fsl,imx31-mmc",
187 		.data = &mxcmci_devtype[IMX31_MMC],
188 	}, {
189 		.compatible = "fsl,mpc5121-sdhc",
190 		.data = &mxcmci_devtype[MPC512X_MMC],
191 	}, {
192 		/* sentinel */
193 	}
194 };
195 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
196 
197 static inline int is_imx31_mmc(struct mxcmci_host *host)
198 {
199 	return host->devtype == IMX31_MMC;
200 }
201 
202 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
203 {
204 	return host->devtype == MPC512X_MMC;
205 }
206 
207 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
208 {
209 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
210 		return ioread32be(host->base + reg);
211 	else
212 		return readl(host->base + reg);
213 }
214 
215 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
216 {
217 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
218 		iowrite32be(val, host->base + reg);
219 	else
220 		writel(val, host->base + reg);
221 }
222 
223 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
224 {
225 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
226 		return ioread32be(host->base + reg);
227 	else
228 		return readw(host->base + reg);
229 }
230 
231 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
232 {
233 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
234 		iowrite32be(val, host->base + reg);
235 	else
236 		writew(val, host->base + reg);
237 }
238 
239 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
240 
241 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
242 {
243 	if (!IS_ERR(host->mmc->supply.vmmc)) {
244 		if (host->power_mode == MMC_POWER_UP)
245 			mmc_regulator_set_ocr(host->mmc,
246 					      host->mmc->supply.vmmc, vdd);
247 		else if (host->power_mode == MMC_POWER_OFF)
248 			mmc_regulator_set_ocr(host->mmc,
249 					      host->mmc->supply.vmmc, 0);
250 	}
251 
252 	if (host->pdata && host->pdata->setpower)
253 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
254 }
255 
256 static inline int mxcmci_use_dma(struct mxcmci_host *host)
257 {
258 	return host->do_dma;
259 }
260 
261 static void mxcmci_softreset(struct mxcmci_host *host)
262 {
263 	int i;
264 
265 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
266 
267 	/* reset sequence */
268 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
269 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
270 			MMC_REG_STR_STP_CLK);
271 
272 	for (i = 0; i < 8; i++)
273 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
274 
275 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
276 }
277 
278 #if IS_ENABLED(CONFIG_PPC_MPC512x)
279 static inline void buffer_swap32(u32 *buf, int len)
280 {
281 	int i;
282 
283 	for (i = 0; i < ((len + 3) / 4); i++) {
284 		*buf = swab32(*buf);
285 		buf++;
286 	}
287 }
288 
289 static void mxcmci_swap_buffers(struct mmc_data *data)
290 {
291 	struct scatterlist *sg;
292 	int i;
293 
294 	for_each_sg(data->sg, sg, data->sg_len, i) {
295 		void *buf = kmap_atomic(sg_page(sg) + sg->offset;
296 		buffer_swap32(buf, sg->length);
297 		kunmap_atomic(buf);
298 }
299 #else
300 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
301 #endif
302 
303 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
304 {
305 	unsigned int nob = data->blocks;
306 	unsigned int blksz = data->blksz;
307 	unsigned int datasize = nob * blksz;
308 	struct scatterlist *sg;
309 	enum dma_transfer_direction slave_dirn;
310 	int i, nents;
311 
312 	host->data = data;
313 	data->bytes_xfered = 0;
314 
315 	mxcmci_writew(host, nob, MMC_REG_NOB);
316 	mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
317 	host->datasize = datasize;
318 
319 	if (!mxcmci_use_dma(host))
320 		return 0;
321 
322 	for_each_sg(data->sg, sg, data->sg_len, i) {
323 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
324 			host->do_dma = 0;
325 			return 0;
326 		}
327 	}
328 
329 	if (data->flags & MMC_DATA_READ) {
330 		host->dma_dir = DMA_FROM_DEVICE;
331 		slave_dirn = DMA_DEV_TO_MEM;
332 	} else {
333 		host->dma_dir = DMA_TO_DEVICE;
334 		slave_dirn = DMA_MEM_TO_DEV;
335 
336 		mxcmci_swap_buffers(data);
337 	}
338 
339 	nents = dma_map_sg(host->dma->device->dev, data->sg,
340 				     data->sg_len,  host->dma_dir);
341 	if (nents != data->sg_len)
342 		return -EINVAL;
343 
344 	host->desc = dmaengine_prep_slave_sg(host->dma,
345 		data->sg, data->sg_len, slave_dirn,
346 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
347 
348 	if (!host->desc) {
349 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
350 				host->dma_dir);
351 		host->do_dma = 0;
352 		return 0; /* Fall back to PIO */
353 	}
354 	wmb();
355 
356 	dmaengine_submit(host->desc);
357 	dma_async_issue_pending(host->dma);
358 
359 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
360 
361 	return 0;
362 }
363 
364 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
365 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
366 
367 static void mxcmci_dma_callback(void *data)
368 {
369 	struct mxcmci_host *host = data;
370 	u32 stat;
371 
372 	del_timer(&host->watchdog);
373 
374 	stat = mxcmci_readl(host, MMC_REG_STATUS);
375 
376 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
377 
378 	mxcmci_data_done(host, stat);
379 }
380 
381 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
382 		unsigned int cmdat)
383 {
384 	u32 int_cntr = host->default_irq_mask;
385 	unsigned long flags;
386 
387 	WARN_ON(host->cmd != NULL);
388 	host->cmd = cmd;
389 
390 	switch (mmc_resp_type(cmd)) {
391 	case MMC_RSP_R1: /* short CRC, OPCODE */
392 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
393 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
394 		break;
395 	case MMC_RSP_R2: /* long 136 bit + CRC */
396 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
397 		break;
398 	case MMC_RSP_R3: /* short */
399 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
400 		break;
401 	case MMC_RSP_NONE:
402 		break;
403 	default:
404 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
405 				mmc_resp_type(cmd));
406 		cmd->error = -EINVAL;
407 		return -EINVAL;
408 	}
409 
410 	int_cntr = INT_END_CMD_RES_EN;
411 
412 	if (mxcmci_use_dma(host)) {
413 		if (host->dma_dir == DMA_FROM_DEVICE) {
414 			host->desc->callback = mxcmci_dma_callback;
415 			host->desc->callback_param = host;
416 		} else {
417 			int_cntr |= INT_WRITE_OP_DONE_EN;
418 		}
419 	}
420 
421 	spin_lock_irqsave(&host->lock, flags);
422 	if (host->use_sdio)
423 		int_cntr |= INT_SDIO_IRQ_EN;
424 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
425 	spin_unlock_irqrestore(&host->lock, flags);
426 
427 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
428 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
429 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
430 
431 	return 0;
432 }
433 
434 static void mxcmci_finish_request(struct mxcmci_host *host,
435 		struct mmc_request *req)
436 {
437 	u32 int_cntr = host->default_irq_mask;
438 	unsigned long flags;
439 
440 	spin_lock_irqsave(&host->lock, flags);
441 	if (host->use_sdio)
442 		int_cntr |= INT_SDIO_IRQ_EN;
443 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
444 	spin_unlock_irqrestore(&host->lock, flags);
445 
446 	host->req = NULL;
447 	host->cmd = NULL;
448 	host->data = NULL;
449 
450 	mmc_request_done(host->mmc, req);
451 }
452 
453 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
454 {
455 	struct mmc_data *data = host->data;
456 	int data_error;
457 
458 	if (mxcmci_use_dma(host)) {
459 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
460 				host->dma_dir);
461 		mxcmci_swap_buffers(data);
462 	}
463 
464 	if (stat & STATUS_ERR_MASK) {
465 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
466 				stat);
467 		if (stat & STATUS_CRC_READ_ERR) {
468 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
469 			data->error = -EILSEQ;
470 		} else if (stat & STATUS_CRC_WRITE_ERR) {
471 			u32 err_code = (stat >> 9) & 0x3;
472 			if (err_code == 2) { /* No CRC response */
473 				dev_err(mmc_dev(host->mmc),
474 					"%s: No CRC -ETIMEDOUT\n", __func__);
475 				data->error = -ETIMEDOUT;
476 			} else {
477 				dev_err(mmc_dev(host->mmc),
478 					"%s: -EILSEQ\n", __func__);
479 				data->error = -EILSEQ;
480 			}
481 		} else if (stat & STATUS_TIME_OUT_READ) {
482 			dev_err(mmc_dev(host->mmc),
483 				"%s: read -ETIMEDOUT\n", __func__);
484 			data->error = -ETIMEDOUT;
485 		} else {
486 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
487 			data->error = -EIO;
488 		}
489 	} else {
490 		data->bytes_xfered = host->datasize;
491 	}
492 
493 	data_error = data->error;
494 
495 	host->data = NULL;
496 
497 	return data_error;
498 }
499 
500 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
501 {
502 	struct mmc_command *cmd = host->cmd;
503 	int i;
504 	u32 a, b, c;
505 
506 	if (!cmd)
507 		return;
508 
509 	if (stat & STATUS_TIME_OUT_RESP) {
510 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
511 		cmd->error = -ETIMEDOUT;
512 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
513 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
514 		cmd->error = -EILSEQ;
515 	}
516 
517 	if (cmd->flags & MMC_RSP_PRESENT) {
518 		if (cmd->flags & MMC_RSP_136) {
519 			for (i = 0; i < 4; i++) {
520 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
521 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
522 				cmd->resp[i] = a << 16 | b;
523 			}
524 		} else {
525 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
526 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
527 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
528 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
529 		}
530 	}
531 }
532 
533 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
534 {
535 	u32 stat;
536 	unsigned long timeout = jiffies + HZ;
537 
538 	do {
539 		stat = mxcmci_readl(host, MMC_REG_STATUS);
540 		if (stat & STATUS_ERR_MASK)
541 			return stat;
542 		if (time_after(jiffies, timeout)) {
543 			mxcmci_softreset(host);
544 			mxcmci_set_clk_rate(host, host->clock);
545 			return STATUS_TIME_OUT_READ;
546 		}
547 		if (stat & mask)
548 			return 0;
549 		cpu_relax();
550 	} while (1);
551 }
552 
553 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
554 {
555 	unsigned int stat;
556 	u32 *buf = _buf;
557 
558 	while (bytes > 3) {
559 		stat = mxcmci_poll_status(host,
560 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
561 		if (stat)
562 			return stat;
563 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
564 		bytes -= 4;
565 	}
566 
567 	if (bytes) {
568 		u8 *b = (u8 *)buf;
569 		u32 tmp;
570 
571 		stat = mxcmci_poll_status(host,
572 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
573 		if (stat)
574 			return stat;
575 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
576 		memcpy(b, &tmp, bytes);
577 	}
578 
579 	return 0;
580 }
581 
582 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
583 {
584 	unsigned int stat;
585 	u32 *buf = _buf;
586 
587 	while (bytes > 3) {
588 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
589 		if (stat)
590 			return stat;
591 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
592 		bytes -= 4;
593 	}
594 
595 	if (bytes) {
596 		u8 *b = (u8 *)buf;
597 		u32 tmp;
598 
599 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
600 		if (stat)
601 			return stat;
602 
603 		memcpy(&tmp, b, bytes);
604 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
605 	}
606 
607 	return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
608 }
609 
610 static int mxcmci_transfer_data(struct mxcmci_host *host)
611 {
612 	struct mmc_data *data = host->req->data;
613 	struct scatterlist *sg;
614 	void *buf;
615 	int stat, i;
616 
617 	host->data = data;
618 	host->datasize = 0;
619 
620 	if (data->flags & MMC_DATA_READ) {
621 		for_each_sg(data->sg, sg, data->sg_len, i) {
622 			buf = kmap_atomic(sg_page(sg) + sg->offset);
623 			stat = mxcmci_pull(host, buf, sg->length);
624 			kunmap(buf);
625 			if (stat)
626 				return stat;
627 			host->datasize += sg->length;
628 		}
629 	} else {
630 		for_each_sg(data->sg, sg, data->sg_len, i) {
631 			buf = kmap_atomic(sg_page(sg) + sg->offset);
632 			stat = mxcmci_push(host, buf, sg->length);
633 			kunmap(buf);
634 			if (stat)
635 				return stat;
636 			host->datasize += sg->length;
637 		}
638 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
639 		if (stat)
640 			return stat;
641 	}
642 	return 0;
643 }
644 
645 static void mxcmci_datawork(struct work_struct *work)
646 {
647 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
648 						  datawork);
649 	int datastat = mxcmci_transfer_data(host);
650 
651 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
652 		MMC_REG_STATUS);
653 	mxcmci_finish_data(host, datastat);
654 
655 	if (host->req->stop) {
656 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
657 			mxcmci_finish_request(host, host->req);
658 			return;
659 		}
660 	} else {
661 		mxcmci_finish_request(host, host->req);
662 	}
663 }
664 
665 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
666 {
667 	struct mmc_request *req;
668 	int data_error;
669 	unsigned long flags;
670 
671 	spin_lock_irqsave(&host->lock, flags);
672 
673 	if (!host->data) {
674 		spin_unlock_irqrestore(&host->lock, flags);
675 		return;
676 	}
677 
678 	if (!host->req) {
679 		spin_unlock_irqrestore(&host->lock, flags);
680 		return;
681 	}
682 
683 	req = host->req;
684 	if (!req->stop)
685 		host->req = NULL; /* we will handle finish req below */
686 
687 	data_error = mxcmci_finish_data(host, stat);
688 
689 	spin_unlock_irqrestore(&host->lock, flags);
690 
691 	if (data_error)
692 		return;
693 
694 	mxcmci_read_response(host, stat);
695 	host->cmd = NULL;
696 
697 	if (req->stop) {
698 		if (mxcmci_start_cmd(host, req->stop, 0)) {
699 			mxcmci_finish_request(host, req);
700 			return;
701 		}
702 	} else {
703 		mxcmci_finish_request(host, req);
704 	}
705 }
706 
707 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
708 {
709 	mxcmci_read_response(host, stat);
710 	host->cmd = NULL;
711 
712 	if (!host->data && host->req) {
713 		mxcmci_finish_request(host, host->req);
714 		return;
715 	}
716 
717 	/* For the DMA case the DMA engine handles the data transfer
718 	 * automatically. For non DMA we have to do it ourselves.
719 	 * Don't do it in interrupt context though.
720 	 */
721 	if (!mxcmci_use_dma(host) && host->data)
722 		schedule_work(&host->datawork);
723 
724 }
725 
726 static irqreturn_t mxcmci_irq(int irq, void *devid)
727 {
728 	struct mxcmci_host *host = devid;
729 	unsigned long flags;
730 	bool sdio_irq;
731 	u32 stat;
732 
733 	stat = mxcmci_readl(host, MMC_REG_STATUS);
734 	mxcmci_writel(host,
735 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
736 			 STATUS_WRITE_OP_DONE),
737 		MMC_REG_STATUS);
738 
739 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
740 
741 	spin_lock_irqsave(&host->lock, flags);
742 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
743 	spin_unlock_irqrestore(&host->lock, flags);
744 
745 	if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
746 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
747 
748 	if (sdio_irq) {
749 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
750 		mmc_signal_sdio_irq(host->mmc);
751 	}
752 
753 	if (stat & STATUS_END_CMD_RESP)
754 		mxcmci_cmd_done(host, stat);
755 
756 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
757 		del_timer(&host->watchdog);
758 		mxcmci_data_done(host, stat);
759 	}
760 
761 	if (host->default_irq_mask &&
762 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
763 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
764 
765 	return IRQ_HANDLED;
766 }
767 
768 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
769 {
770 	struct mxcmci_host *host = mmc_priv(mmc);
771 	unsigned int cmdat = host->cmdat;
772 	int error;
773 
774 	WARN_ON(host->req != NULL);
775 
776 	host->req = req;
777 	host->cmdat &= ~CMD_DAT_CONT_INIT;
778 
779 	if (host->dma)
780 		host->do_dma = 1;
781 
782 	if (req->data) {
783 		error = mxcmci_setup_data(host, req->data);
784 		if (error) {
785 			req->cmd->error = error;
786 			goto out;
787 		}
788 
789 
790 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
791 
792 		if (req->data->flags & MMC_DATA_WRITE)
793 			cmdat |= CMD_DAT_CONT_WRITE;
794 	}
795 
796 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
797 
798 out:
799 	if (error)
800 		mxcmci_finish_request(host, req);
801 }
802 
803 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
804 {
805 	unsigned int divider;
806 	int prescaler = 0;
807 	unsigned int clk_in = clk_get_rate(host->clk_per);
808 
809 	while (prescaler <= 0x800) {
810 		for (divider = 1; divider <= 0xF; divider++) {
811 			int x;
812 
813 			x = (clk_in / (divider + 1));
814 
815 			if (prescaler)
816 				x /= (prescaler * 2);
817 
818 			if (x <= clk_ios)
819 				break;
820 		}
821 		if (divider < 0x10)
822 			break;
823 
824 		if (prescaler == 0)
825 			prescaler = 1;
826 		else
827 			prescaler <<= 1;
828 	}
829 
830 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
831 
832 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
833 			prescaler, divider, clk_in, clk_ios);
834 }
835 
836 static int mxcmci_setup_dma(struct mmc_host *mmc)
837 {
838 	struct mxcmci_host *host = mmc_priv(mmc);
839 	struct dma_slave_config *config = &host->dma_slave_config;
840 
841 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
842 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
843 	config->dst_addr_width = 4;
844 	config->src_addr_width = 4;
845 	config->dst_maxburst = host->burstlen;
846 	config->src_maxburst = host->burstlen;
847 	config->device_fc = false;
848 
849 	return dmaengine_slave_config(host->dma, config);
850 }
851 
852 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
853 {
854 	struct mxcmci_host *host = mmc_priv(mmc);
855 	int burstlen, ret;
856 
857 	/*
858 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
859 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
860 	 */
861 	if (ios->bus_width == MMC_BUS_WIDTH_4)
862 		burstlen = 16;
863 	else
864 		burstlen = 4;
865 
866 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
867 		host->burstlen = burstlen;
868 		ret = mxcmci_setup_dma(mmc);
869 		if (ret) {
870 			dev_err(mmc_dev(host->mmc),
871 				"failed to config DMA channel. Falling back to PIO\n");
872 			dma_release_channel(host->dma);
873 			host->do_dma = 0;
874 			host->dma = NULL;
875 		}
876 	}
877 
878 	if (ios->bus_width == MMC_BUS_WIDTH_4)
879 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
880 	else
881 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
882 
883 	if (host->power_mode != ios->power_mode) {
884 		host->power_mode = ios->power_mode;
885 		mxcmci_set_power(host, ios->vdd);
886 
887 		if (ios->power_mode == MMC_POWER_ON)
888 			host->cmdat |= CMD_DAT_CONT_INIT;
889 	}
890 
891 	if (ios->clock) {
892 		mxcmci_set_clk_rate(host, ios->clock);
893 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
894 	} else {
895 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
896 	}
897 
898 	host->clock = ios->clock;
899 }
900 
901 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
902 {
903 	struct mmc_host *mmc = data;
904 
905 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
906 
907 	mmc_detect_change(mmc, msecs_to_jiffies(250));
908 	return IRQ_HANDLED;
909 }
910 
911 static int mxcmci_get_ro(struct mmc_host *mmc)
912 {
913 	struct mxcmci_host *host = mmc_priv(mmc);
914 
915 	if (host->pdata && host->pdata->get_ro)
916 		return !!host->pdata->get_ro(mmc_dev(mmc));
917 	/*
918 	 * If board doesn't support read only detection (no mmc_gpio
919 	 * context or gpio is invalid), then let the mmc core decide
920 	 * what to do.
921 	 */
922 	return mmc_gpio_get_ro(mmc);
923 }
924 
925 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
926 {
927 	struct mxcmci_host *host = mmc_priv(mmc);
928 	unsigned long flags;
929 	u32 int_cntr;
930 
931 	spin_lock_irqsave(&host->lock, flags);
932 	host->use_sdio = enable;
933 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
934 
935 	if (enable)
936 		int_cntr |= INT_SDIO_IRQ_EN;
937 	else
938 		int_cntr &= ~INT_SDIO_IRQ_EN;
939 
940 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
941 	spin_unlock_irqrestore(&host->lock, flags);
942 }
943 
944 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
945 {
946 	struct mxcmci_host *mxcmci = mmc_priv(host);
947 
948 	/*
949 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
950 	 * multi-block transfers when connected SDIO peripheral doesn't
951 	 * drive the BUSY line as required by the specs.
952 	 * One way to prevent this is to only allow 1-bit transfers.
953 	 */
954 
955 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
956 		host->caps &= ~MMC_CAP_4_BIT_DATA;
957 	else
958 		host->caps |= MMC_CAP_4_BIT_DATA;
959 }
960 
961 static bool filter(struct dma_chan *chan, void *param)
962 {
963 	struct mxcmci_host *host = param;
964 
965 	if (!imx_dma_is_general_purpose(chan))
966 		return false;
967 
968 	chan->private = &host->dma_data;
969 
970 	return true;
971 }
972 
973 static void mxcmci_watchdog(struct timer_list *t)
974 {
975 	struct mxcmci_host *host = from_timer(host, t, watchdog);
976 	struct mmc_request *req = host->req;
977 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
978 
979 	if (host->dma_dir == DMA_FROM_DEVICE) {
980 		dmaengine_terminate_all(host->dma);
981 		dev_err(mmc_dev(host->mmc),
982 			"%s: read time out (status = 0x%08x)\n",
983 			__func__, stat);
984 	} else {
985 		dev_err(mmc_dev(host->mmc),
986 			"%s: write time out (status = 0x%08x)\n",
987 			__func__, stat);
988 		mxcmci_softreset(host);
989 	}
990 
991 	/* Mark transfer as erroneus and inform the upper layers */
992 
993 	if (host->data)
994 		host->data->error = -ETIMEDOUT;
995 	host->req = NULL;
996 	host->cmd = NULL;
997 	host->data = NULL;
998 	mmc_request_done(host->mmc, req);
999 }
1000 
1001 static const struct mmc_host_ops mxcmci_ops = {
1002 	.request		= mxcmci_request,
1003 	.set_ios		= mxcmci_set_ios,
1004 	.get_ro			= mxcmci_get_ro,
1005 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
1006 	.init_card		= mxcmci_init_card,
1007 };
1008 
1009 static int mxcmci_probe(struct platform_device *pdev)
1010 {
1011 	struct mmc_host *mmc;
1012 	struct mxcmci_host *host;
1013 	struct resource *res;
1014 	int ret = 0, irq;
1015 	bool dat3_card_detect = false;
1016 	dma_cap_mask_t mask;
1017 	const struct of_device_id *of_id;
1018 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
1019 
1020 	pr_info("i.MX/MPC512x SDHC driver\n");
1021 
1022 	of_id = of_match_device(mxcmci_of_match, &pdev->dev);
1023 
1024 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1025 	irq = platform_get_irq(pdev, 0);
1026 	if (irq < 0) {
1027 		dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
1028 		return irq;
1029 	}
1030 
1031 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
1032 	if (!mmc)
1033 		return -ENOMEM;
1034 
1035 	host = mmc_priv(mmc);
1036 
1037 	host->base = devm_ioremap_resource(&pdev->dev, res);
1038 	if (IS_ERR(host->base)) {
1039 		ret = PTR_ERR(host->base);
1040 		goto out_free;
1041 	}
1042 
1043 	host->phys_base = res->start;
1044 
1045 	ret = mmc_of_parse(mmc);
1046 	if (ret)
1047 		goto out_free;
1048 	mmc->ops = &mxcmci_ops;
1049 
1050 	/* For devicetree parsing, the bus width is read from devicetree */
1051 	if (pdata)
1052 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1053 	else
1054 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1055 
1056 	/* MMC core transfer sizes tunable parameters */
1057 	mmc->max_blk_size = 2048;
1058 	mmc->max_blk_count = 65535;
1059 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1060 	mmc->max_seg_size = mmc->max_req_size;
1061 
1062 	if (of_id) {
1063 		const struct platform_device_id *id_entry = of_id->data;
1064 		host->devtype = id_entry->driver_data;
1065 	} else {
1066 		host->devtype = pdev->id_entry->driver_data;
1067 	}
1068 
1069 	/* adjust max_segs after devtype detection */
1070 	if (!is_mpc512x_mmc(host))
1071 		mmc->max_segs = 64;
1072 
1073 	host->mmc = mmc;
1074 	host->pdata = pdata;
1075 	spin_lock_init(&host->lock);
1076 
1077 	if (pdata)
1078 		dat3_card_detect = pdata->dat3_card_detect;
1079 	else if (mmc_card_is_removable(mmc)
1080 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1081 		dat3_card_detect = true;
1082 
1083 	ret = mmc_regulator_get_supply(mmc);
1084 	if (ret)
1085 		goto out_free;
1086 
1087 	if (!mmc->ocr_avail) {
1088 		if (pdata && pdata->ocr_avail)
1089 			mmc->ocr_avail = pdata->ocr_avail;
1090 		else
1091 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1092 	}
1093 
1094 	if (dat3_card_detect)
1095 		host->default_irq_mask =
1096 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1097 	else
1098 		host->default_irq_mask = 0;
1099 
1100 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1101 	if (IS_ERR(host->clk_ipg)) {
1102 		ret = PTR_ERR(host->clk_ipg);
1103 		goto out_free;
1104 	}
1105 
1106 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1107 	if (IS_ERR(host->clk_per)) {
1108 		ret = PTR_ERR(host->clk_per);
1109 		goto out_free;
1110 	}
1111 
1112 	ret = clk_prepare_enable(host->clk_per);
1113 	if (ret)
1114 		goto out_free;
1115 
1116 	ret = clk_prepare_enable(host->clk_ipg);
1117 	if (ret)
1118 		goto out_clk_per_put;
1119 
1120 	mxcmci_softreset(host);
1121 
1122 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1123 	if (host->rev_no != 0x400) {
1124 		ret = -ENODEV;
1125 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1126 			host->rev_no);
1127 		goto out_clk_put;
1128 	}
1129 
1130 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1131 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1132 
1133 	/* recommended in data sheet */
1134 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1135 
1136 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1137 
1138 	if (!host->pdata) {
1139 		host->dma = dma_request_slave_channel(&pdev->dev, "rx-tx");
1140 	} else {
1141 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1142 		if (res) {
1143 			host->dmareq = res->start;
1144 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1145 			host->dma_data.priority = DMA_PRIO_LOW;
1146 			host->dma_data.dma_request = host->dmareq;
1147 			dma_cap_zero(mask);
1148 			dma_cap_set(DMA_SLAVE, mask);
1149 			host->dma = dma_request_channel(mask, filter, host);
1150 		}
1151 	}
1152 	if (host->dma)
1153 		mmc->max_seg_size = dma_get_max_seg_size(
1154 				host->dma->device->dev);
1155 	else
1156 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1157 
1158 	INIT_WORK(&host->datawork, mxcmci_datawork);
1159 
1160 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1161 			       dev_name(&pdev->dev), host);
1162 	if (ret)
1163 		goto out_free_dma;
1164 
1165 	platform_set_drvdata(pdev, mmc);
1166 
1167 	if (host->pdata && host->pdata->init) {
1168 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1169 				host->mmc);
1170 		if (ret)
1171 			goto out_free_dma;
1172 	}
1173 
1174 	timer_setup(&host->watchdog, mxcmci_watchdog, 0);
1175 
1176 	mmc_add_host(mmc);
1177 
1178 	return 0;
1179 
1180 out_free_dma:
1181 	if (host->dma)
1182 		dma_release_channel(host->dma);
1183 
1184 out_clk_put:
1185 	clk_disable_unprepare(host->clk_ipg);
1186 out_clk_per_put:
1187 	clk_disable_unprepare(host->clk_per);
1188 
1189 out_free:
1190 	mmc_free_host(mmc);
1191 
1192 	return ret;
1193 }
1194 
1195 static int mxcmci_remove(struct platform_device *pdev)
1196 {
1197 	struct mmc_host *mmc = platform_get_drvdata(pdev);
1198 	struct mxcmci_host *host = mmc_priv(mmc);
1199 
1200 	mmc_remove_host(mmc);
1201 
1202 	if (host->pdata && host->pdata->exit)
1203 		host->pdata->exit(&pdev->dev, mmc);
1204 
1205 	if (host->dma)
1206 		dma_release_channel(host->dma);
1207 
1208 	clk_disable_unprepare(host->clk_per);
1209 	clk_disable_unprepare(host->clk_ipg);
1210 
1211 	mmc_free_host(mmc);
1212 
1213 	return 0;
1214 }
1215 
1216 static int __maybe_unused mxcmci_suspend(struct device *dev)
1217 {
1218 	struct mmc_host *mmc = dev_get_drvdata(dev);
1219 	struct mxcmci_host *host = mmc_priv(mmc);
1220 
1221 	clk_disable_unprepare(host->clk_per);
1222 	clk_disable_unprepare(host->clk_ipg);
1223 	return 0;
1224 }
1225 
1226 static int __maybe_unused mxcmci_resume(struct device *dev)
1227 {
1228 	struct mmc_host *mmc = dev_get_drvdata(dev);
1229 	struct mxcmci_host *host = mmc_priv(mmc);
1230 	int ret;
1231 
1232 	ret = clk_prepare_enable(host->clk_per);
1233 	if (ret)
1234 		return ret;
1235 
1236 	ret = clk_prepare_enable(host->clk_ipg);
1237 	if (ret)
1238 		clk_disable_unprepare(host->clk_per);
1239 
1240 	return ret;
1241 }
1242 
1243 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1244 
1245 static struct platform_driver mxcmci_driver = {
1246 	.probe		= mxcmci_probe,
1247 	.remove		= mxcmci_remove,
1248 	.id_table	= mxcmci_devtype,
1249 	.driver		= {
1250 		.name		= DRIVER_NAME,
1251 		.pm	= &mxcmci_pm_ops,
1252 		.of_match_table	= mxcmci_of_match,
1253 	}
1254 };
1255 
1256 module_platform_driver(mxcmci_driver);
1257 
1258 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1259 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1260 MODULE_LICENSE("GPL");
1261 MODULE_ALIAS("platform:mxc-mmc");
1262