xref: /openbmc/linux/drivers/mmc/host/mxcmmc.c (revision 84b102f5)
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_device.h>
35 #include <linux/of_dma.h>
36 #include <linux/mmc/slot-gpio.h>
37 
38 #include <asm/dma.h>
39 #include <asm/irq.h>
40 #include <linux/platform_data/mmc-mxcmmc.h>
41 
42 #include <linux/platform_data/dma-imx.h>
43 
44 #define DRIVER_NAME "mxc-mmc"
45 #define MXCMCI_TIMEOUT_MS 10000
46 
47 #define MMC_REG_STR_STP_CLK		0x00
48 #define MMC_REG_STATUS			0x04
49 #define MMC_REG_CLK_RATE		0x08
50 #define MMC_REG_CMD_DAT_CONT		0x0C
51 #define MMC_REG_RES_TO			0x10
52 #define MMC_REG_READ_TO			0x14
53 #define MMC_REG_BLK_LEN			0x18
54 #define MMC_REG_NOB			0x1C
55 #define MMC_REG_REV_NO			0x20
56 #define MMC_REG_INT_CNTR		0x24
57 #define MMC_REG_CMD			0x28
58 #define MMC_REG_ARG			0x2C
59 #define MMC_REG_RES_FIFO		0x34
60 #define MMC_REG_BUFFER_ACCESS		0x38
61 
62 #define STR_STP_CLK_RESET               (1 << 3)
63 #define STR_STP_CLK_START_CLK           (1 << 1)
64 #define STR_STP_CLK_STOP_CLK            (1 << 0)
65 
66 #define STATUS_CARD_INSERTION		(1 << 31)
67 #define STATUS_CARD_REMOVAL		(1 << 30)
68 #define STATUS_YBUF_EMPTY		(1 << 29)
69 #define STATUS_XBUF_EMPTY		(1 << 28)
70 #define STATUS_YBUF_FULL		(1 << 27)
71 #define STATUS_XBUF_FULL		(1 << 26)
72 #define STATUS_BUF_UND_RUN		(1 << 25)
73 #define STATUS_BUF_OVFL			(1 << 24)
74 #define STATUS_SDIO_INT_ACTIVE		(1 << 14)
75 #define STATUS_END_CMD_RESP		(1 << 13)
76 #define STATUS_WRITE_OP_DONE		(1 << 12)
77 #define STATUS_DATA_TRANS_DONE		(1 << 11)
78 #define STATUS_READ_OP_DONE		(1 << 11)
79 #define STATUS_WR_CRC_ERROR_CODE_MASK	(3 << 10)
80 #define STATUS_CARD_BUS_CLK_RUN		(1 << 8)
81 #define STATUS_BUF_READ_RDY		(1 << 7)
82 #define STATUS_BUF_WRITE_RDY		(1 << 6)
83 #define STATUS_RESP_CRC_ERR		(1 << 5)
84 #define STATUS_CRC_READ_ERR		(1 << 3)
85 #define STATUS_CRC_WRITE_ERR		(1 << 2)
86 #define STATUS_TIME_OUT_RESP		(1 << 1)
87 #define STATUS_TIME_OUT_READ		(1 << 0)
88 #define STATUS_ERR_MASK			0x2f
89 
90 #define CMD_DAT_CONT_CMD_RESP_LONG_OFF	(1 << 12)
91 #define CMD_DAT_CONT_STOP_READWAIT	(1 << 11)
92 #define CMD_DAT_CONT_START_READWAIT	(1 << 10)
93 #define CMD_DAT_CONT_BUS_WIDTH_4	(2 << 8)
94 #define CMD_DAT_CONT_INIT		(1 << 7)
95 #define CMD_DAT_CONT_WRITE		(1 << 4)
96 #define CMD_DAT_CONT_DATA_ENABLE	(1 << 3)
97 #define CMD_DAT_CONT_RESPONSE_48BIT_CRC	(1 << 0)
98 #define CMD_DAT_CONT_RESPONSE_136BIT	(2 << 0)
99 #define CMD_DAT_CONT_RESPONSE_48BIT	(3 << 0)
100 
101 #define INT_SDIO_INT_WKP_EN		(1 << 18)
102 #define INT_CARD_INSERTION_WKP_EN	(1 << 17)
103 #define INT_CARD_REMOVAL_WKP_EN		(1 << 16)
104 #define INT_CARD_INSERTION_EN		(1 << 15)
105 #define INT_CARD_REMOVAL_EN		(1 << 14)
106 #define INT_SDIO_IRQ_EN			(1 << 13)
107 #define INT_DAT0_EN			(1 << 12)
108 #define INT_BUF_READ_EN			(1 << 4)
109 #define INT_BUF_WRITE_EN		(1 << 3)
110 #define INT_END_CMD_RES_EN		(1 << 2)
111 #define INT_WRITE_OP_DONE_EN		(1 << 1)
112 #define INT_READ_OP_EN			(1 << 0)
113 
114 enum mxcmci_type {
115 	IMX21_MMC,
116 	IMX31_MMC,
117 	MPC512X_MMC,
118 };
119 
120 struct mxcmci_host {
121 	struct mmc_host		*mmc;
122 	void __iomem		*base;
123 	dma_addr_t		phys_base;
124 	int			detect_irq;
125 	struct dma_chan		*dma;
126 	struct dma_async_tx_descriptor *desc;
127 	int			do_dma;
128 	int			default_irq_mask;
129 	int			use_sdio;
130 	unsigned int		power_mode;
131 	struct imxmmc_platform_data *pdata;
132 
133 	struct mmc_request	*req;
134 	struct mmc_command	*cmd;
135 	struct mmc_data		*data;
136 
137 	unsigned int		datasize;
138 	unsigned int		dma_dir;
139 
140 	u16			rev_no;
141 	unsigned int		cmdat;
142 
143 	struct clk		*clk_ipg;
144 	struct clk		*clk_per;
145 
146 	int			clock;
147 
148 	struct work_struct	datawork;
149 	spinlock_t		lock;
150 
151 	int			burstlen;
152 	int			dmareq;
153 	struct dma_slave_config dma_slave_config;
154 	struct imx_dma_data	dma_data;
155 
156 	struct timer_list	watchdog;
157 	enum mxcmci_type	devtype;
158 };
159 
160 static const struct of_device_id mxcmci_of_match[] = {
161 	{
162 		.compatible = "fsl,imx21-mmc",
163 		.data = (void *) IMX21_MMC,
164 	}, {
165 		.compatible = "fsl,imx31-mmc",
166 		.data = (void *) IMX31_MMC,
167 	}, {
168 		.compatible = "fsl,mpc5121-sdhc",
169 		.data = (void *) MPC512X_MMC,
170 	}, {
171 		/* sentinel */
172 	}
173 };
174 MODULE_DEVICE_TABLE(of, mxcmci_of_match);
175 
176 static inline int is_imx31_mmc(struct mxcmci_host *host)
177 {
178 	return host->devtype == IMX31_MMC;
179 }
180 
181 static inline int is_mpc512x_mmc(struct mxcmci_host *host)
182 {
183 	return host->devtype == MPC512X_MMC;
184 }
185 
186 static inline u32 mxcmci_readl(struct mxcmci_host *host, int reg)
187 {
188 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
189 		return ioread32be(host->base + reg);
190 	else
191 		return readl(host->base + reg);
192 }
193 
194 static inline void mxcmci_writel(struct mxcmci_host *host, u32 val, int reg)
195 {
196 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
197 		iowrite32be(val, host->base + reg);
198 	else
199 		writel(val, host->base + reg);
200 }
201 
202 static inline u16 mxcmci_readw(struct mxcmci_host *host, int reg)
203 {
204 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
205 		return ioread32be(host->base + reg);
206 	else
207 		return readw(host->base + reg);
208 }
209 
210 static inline void mxcmci_writew(struct mxcmci_host *host, u16 val, int reg)
211 {
212 	if (IS_ENABLED(CONFIG_PPC_MPC512x))
213 		iowrite32be(val, host->base + reg);
214 	else
215 		writew(val, host->base + reg);
216 }
217 
218 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios);
219 
220 static void mxcmci_set_power(struct mxcmci_host *host, unsigned int vdd)
221 {
222 	if (!IS_ERR(host->mmc->supply.vmmc)) {
223 		if (host->power_mode == MMC_POWER_UP)
224 			mmc_regulator_set_ocr(host->mmc,
225 					      host->mmc->supply.vmmc, vdd);
226 		else if (host->power_mode == MMC_POWER_OFF)
227 			mmc_regulator_set_ocr(host->mmc,
228 					      host->mmc->supply.vmmc, 0);
229 	}
230 
231 	if (host->pdata && host->pdata->setpower)
232 		host->pdata->setpower(mmc_dev(host->mmc), vdd);
233 }
234 
235 static inline int mxcmci_use_dma(struct mxcmci_host *host)
236 {
237 	return host->do_dma;
238 }
239 
240 static void mxcmci_softreset(struct mxcmci_host *host)
241 {
242 	int i;
243 
244 	dev_dbg(mmc_dev(host->mmc), "mxcmci_softreset\n");
245 
246 	/* reset sequence */
247 	mxcmci_writew(host, STR_STP_CLK_RESET, MMC_REG_STR_STP_CLK);
248 	mxcmci_writew(host, STR_STP_CLK_RESET | STR_STP_CLK_START_CLK,
249 			MMC_REG_STR_STP_CLK);
250 
251 	for (i = 0; i < 8; i++)
252 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
253 
254 	mxcmci_writew(host, 0xff, MMC_REG_RES_TO);
255 }
256 
257 #if IS_ENABLED(CONFIG_PPC_MPC512x)
258 static inline void buffer_swap32(u32 *buf, int len)
259 {
260 	int i;
261 
262 	for (i = 0; i < ((len + 3) / 4); i++) {
263 		*buf = swab32(*buf);
264 		buf++;
265 	}
266 }
267 
268 static void mxcmci_swap_buffers(struct mmc_data *data)
269 {
270 	struct scatterlist *sg;
271 	int i;
272 
273 	for_each_sg(data->sg, sg, data->sg_len, i)
274 		buffer_swap32(sg_virt(sg), sg->length);
275 }
276 #else
277 static inline void mxcmci_swap_buffers(struct mmc_data *data) {}
278 #endif
279 
280 static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
281 {
282 	unsigned int nob = data->blocks;
283 	unsigned int blksz = data->blksz;
284 	unsigned int datasize = nob * blksz;
285 	struct scatterlist *sg;
286 	enum dma_transfer_direction slave_dirn;
287 	int i, nents;
288 
289 	host->data = data;
290 	data->bytes_xfered = 0;
291 
292 	mxcmci_writew(host, nob, MMC_REG_NOB);
293 	mxcmci_writew(host, blksz, MMC_REG_BLK_LEN);
294 	host->datasize = datasize;
295 
296 	if (!mxcmci_use_dma(host))
297 		return 0;
298 
299 	for_each_sg(data->sg, sg, data->sg_len, i) {
300 		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
301 			host->do_dma = 0;
302 			return 0;
303 		}
304 	}
305 
306 	if (data->flags & MMC_DATA_READ) {
307 		host->dma_dir = DMA_FROM_DEVICE;
308 		slave_dirn = DMA_DEV_TO_MEM;
309 	} else {
310 		host->dma_dir = DMA_TO_DEVICE;
311 		slave_dirn = DMA_MEM_TO_DEV;
312 
313 		mxcmci_swap_buffers(data);
314 	}
315 
316 	nents = dma_map_sg(host->dma->device->dev, data->sg,
317 				     data->sg_len,  host->dma_dir);
318 	if (nents != data->sg_len)
319 		return -EINVAL;
320 
321 	host->desc = dmaengine_prep_slave_sg(host->dma,
322 		data->sg, data->sg_len, slave_dirn,
323 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
324 
325 	if (!host->desc) {
326 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
327 				host->dma_dir);
328 		host->do_dma = 0;
329 		return 0; /* Fall back to PIO */
330 	}
331 	wmb();
332 
333 	dmaengine_submit(host->desc);
334 	dma_async_issue_pending(host->dma);
335 
336 	mod_timer(&host->watchdog, jiffies + msecs_to_jiffies(MXCMCI_TIMEOUT_MS));
337 
338 	return 0;
339 }
340 
341 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat);
342 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat);
343 
344 static void mxcmci_dma_callback(void *data)
345 {
346 	struct mxcmci_host *host = data;
347 	u32 stat;
348 
349 	del_timer(&host->watchdog);
350 
351 	stat = mxcmci_readl(host, MMC_REG_STATUS);
352 
353 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
354 
355 	mxcmci_data_done(host, stat);
356 }
357 
358 static int mxcmci_start_cmd(struct mxcmci_host *host, struct mmc_command *cmd,
359 		unsigned int cmdat)
360 {
361 	u32 int_cntr = host->default_irq_mask;
362 	unsigned long flags;
363 
364 	WARN_ON(host->cmd != NULL);
365 	host->cmd = cmd;
366 
367 	switch (mmc_resp_type(cmd)) {
368 	case MMC_RSP_R1: /* short CRC, OPCODE */
369 	case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
370 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT_CRC;
371 		break;
372 	case MMC_RSP_R2: /* long 136 bit + CRC */
373 		cmdat |= CMD_DAT_CONT_RESPONSE_136BIT;
374 		break;
375 	case MMC_RSP_R3: /* short */
376 		cmdat |= CMD_DAT_CONT_RESPONSE_48BIT;
377 		break;
378 	case MMC_RSP_NONE:
379 		break;
380 	default:
381 		dev_err(mmc_dev(host->mmc), "unhandled response type 0x%x\n",
382 				mmc_resp_type(cmd));
383 		cmd->error = -EINVAL;
384 		return -EINVAL;
385 	}
386 
387 	int_cntr = INT_END_CMD_RES_EN;
388 
389 	if (mxcmci_use_dma(host)) {
390 		if (host->dma_dir == DMA_FROM_DEVICE) {
391 			host->desc->callback = mxcmci_dma_callback;
392 			host->desc->callback_param = host;
393 		} else {
394 			int_cntr |= INT_WRITE_OP_DONE_EN;
395 		}
396 	}
397 
398 	spin_lock_irqsave(&host->lock, flags);
399 	if (host->use_sdio)
400 		int_cntr |= INT_SDIO_IRQ_EN;
401 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
402 	spin_unlock_irqrestore(&host->lock, flags);
403 
404 	mxcmci_writew(host, cmd->opcode, MMC_REG_CMD);
405 	mxcmci_writel(host, cmd->arg, MMC_REG_ARG);
406 	mxcmci_writew(host, cmdat, MMC_REG_CMD_DAT_CONT);
407 
408 	return 0;
409 }
410 
411 static void mxcmci_finish_request(struct mxcmci_host *host,
412 		struct mmc_request *req)
413 {
414 	u32 int_cntr = host->default_irq_mask;
415 	unsigned long flags;
416 
417 	spin_lock_irqsave(&host->lock, flags);
418 	if (host->use_sdio)
419 		int_cntr |= INT_SDIO_IRQ_EN;
420 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
421 	spin_unlock_irqrestore(&host->lock, flags);
422 
423 	host->req = NULL;
424 	host->cmd = NULL;
425 	host->data = NULL;
426 
427 	mmc_request_done(host->mmc, req);
428 }
429 
430 static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
431 {
432 	struct mmc_data *data = host->data;
433 	int data_error;
434 
435 	if (mxcmci_use_dma(host)) {
436 		dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
437 				host->dma_dir);
438 		mxcmci_swap_buffers(data);
439 	}
440 
441 	if (stat & STATUS_ERR_MASK) {
442 		dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",
443 				stat);
444 		if (stat & STATUS_CRC_READ_ERR) {
445 			dev_err(mmc_dev(host->mmc), "%s: -EILSEQ\n", __func__);
446 			data->error = -EILSEQ;
447 		} else if (stat & STATUS_CRC_WRITE_ERR) {
448 			u32 err_code = (stat >> 9) & 0x3;
449 			if (err_code == 2) { /* No CRC response */
450 				dev_err(mmc_dev(host->mmc),
451 					"%s: No CRC -ETIMEDOUT\n", __func__);
452 				data->error = -ETIMEDOUT;
453 			} else {
454 				dev_err(mmc_dev(host->mmc),
455 					"%s: -EILSEQ\n", __func__);
456 				data->error = -EILSEQ;
457 			}
458 		} else if (stat & STATUS_TIME_OUT_READ) {
459 			dev_err(mmc_dev(host->mmc),
460 				"%s: read -ETIMEDOUT\n", __func__);
461 			data->error = -ETIMEDOUT;
462 		} else {
463 			dev_err(mmc_dev(host->mmc), "%s: -EIO\n", __func__);
464 			data->error = -EIO;
465 		}
466 	} else {
467 		data->bytes_xfered = host->datasize;
468 	}
469 
470 	data_error = data->error;
471 
472 	host->data = NULL;
473 
474 	return data_error;
475 }
476 
477 static void mxcmci_read_response(struct mxcmci_host *host, unsigned int stat)
478 {
479 	struct mmc_command *cmd = host->cmd;
480 	int i;
481 	u32 a, b, c;
482 
483 	if (!cmd)
484 		return;
485 
486 	if (stat & STATUS_TIME_OUT_RESP) {
487 		dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
488 		cmd->error = -ETIMEDOUT;
489 	} else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
490 		dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
491 		cmd->error = -EILSEQ;
492 	}
493 
494 	if (cmd->flags & MMC_RSP_PRESENT) {
495 		if (cmd->flags & MMC_RSP_136) {
496 			for (i = 0; i < 4; i++) {
497 				a = mxcmci_readw(host, MMC_REG_RES_FIFO);
498 				b = mxcmci_readw(host, MMC_REG_RES_FIFO);
499 				cmd->resp[i] = a << 16 | b;
500 			}
501 		} else {
502 			a = mxcmci_readw(host, MMC_REG_RES_FIFO);
503 			b = mxcmci_readw(host, MMC_REG_RES_FIFO);
504 			c = mxcmci_readw(host, MMC_REG_RES_FIFO);
505 			cmd->resp[0] = a << 24 | b << 8 | c >> 8;
506 		}
507 	}
508 }
509 
510 static int mxcmci_poll_status(struct mxcmci_host *host, u32 mask)
511 {
512 	u32 stat;
513 	unsigned long timeout = jiffies + HZ;
514 
515 	do {
516 		stat = mxcmci_readl(host, MMC_REG_STATUS);
517 		if (stat & STATUS_ERR_MASK)
518 			return stat;
519 		if (time_after(jiffies, timeout)) {
520 			mxcmci_softreset(host);
521 			mxcmci_set_clk_rate(host, host->clock);
522 			return STATUS_TIME_OUT_READ;
523 		}
524 		if (stat & mask)
525 			return 0;
526 		cpu_relax();
527 	} while (1);
528 }
529 
530 static int mxcmci_pull(struct mxcmci_host *host, void *_buf, int bytes)
531 {
532 	unsigned int stat;
533 	u32 *buf = _buf;
534 
535 	while (bytes > 3) {
536 		stat = mxcmci_poll_status(host,
537 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
538 		if (stat)
539 			return stat;
540 		*buf++ = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
541 		bytes -= 4;
542 	}
543 
544 	if (bytes) {
545 		u8 *b = (u8 *)buf;
546 		u32 tmp;
547 
548 		stat = mxcmci_poll_status(host,
549 				STATUS_BUF_READ_RDY | STATUS_READ_OP_DONE);
550 		if (stat)
551 			return stat;
552 		tmp = cpu_to_le32(mxcmci_readl(host, MMC_REG_BUFFER_ACCESS));
553 		memcpy(b, &tmp, bytes);
554 	}
555 
556 	return 0;
557 }
558 
559 static int mxcmci_push(struct mxcmci_host *host, void *_buf, int bytes)
560 {
561 	unsigned int stat;
562 	u32 *buf = _buf;
563 
564 	while (bytes > 3) {
565 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
566 		if (stat)
567 			return stat;
568 		mxcmci_writel(host, cpu_to_le32(*buf++), MMC_REG_BUFFER_ACCESS);
569 		bytes -= 4;
570 	}
571 
572 	if (bytes) {
573 		u8 *b = (u8 *)buf;
574 		u32 tmp;
575 
576 		stat = mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
577 		if (stat)
578 			return stat;
579 
580 		memcpy(&tmp, b, bytes);
581 		mxcmci_writel(host, cpu_to_le32(tmp), MMC_REG_BUFFER_ACCESS);
582 	}
583 
584 	return mxcmci_poll_status(host, STATUS_BUF_WRITE_RDY);
585 }
586 
587 static int mxcmci_transfer_data(struct mxcmci_host *host)
588 {
589 	struct mmc_data *data = host->req->data;
590 	struct scatterlist *sg;
591 	int stat, i;
592 
593 	host->data = data;
594 	host->datasize = 0;
595 
596 	if (data->flags & MMC_DATA_READ) {
597 		for_each_sg(data->sg, sg, data->sg_len, i) {
598 			stat = mxcmci_pull(host, sg_virt(sg), sg->length);
599 			if (stat)
600 				return stat;
601 			host->datasize += sg->length;
602 		}
603 	} else {
604 		for_each_sg(data->sg, sg, data->sg_len, i) {
605 			stat = mxcmci_push(host, sg_virt(sg), sg->length);
606 			if (stat)
607 				return stat;
608 			host->datasize += sg->length;
609 		}
610 		stat = mxcmci_poll_status(host, STATUS_WRITE_OP_DONE);
611 		if (stat)
612 			return stat;
613 	}
614 	return 0;
615 }
616 
617 static void mxcmci_datawork(struct work_struct *work)
618 {
619 	struct mxcmci_host *host = container_of(work, struct mxcmci_host,
620 						  datawork);
621 	int datastat = mxcmci_transfer_data(host);
622 
623 	mxcmci_writel(host, STATUS_READ_OP_DONE | STATUS_WRITE_OP_DONE,
624 		MMC_REG_STATUS);
625 	mxcmci_finish_data(host, datastat);
626 
627 	if (host->req->stop) {
628 		if (mxcmci_start_cmd(host, host->req->stop, 0)) {
629 			mxcmci_finish_request(host, host->req);
630 			return;
631 		}
632 	} else {
633 		mxcmci_finish_request(host, host->req);
634 	}
635 }
636 
637 static void mxcmci_data_done(struct mxcmci_host *host, unsigned int stat)
638 {
639 	struct mmc_request *req;
640 	int data_error;
641 	unsigned long flags;
642 
643 	spin_lock_irqsave(&host->lock, flags);
644 
645 	if (!host->data) {
646 		spin_unlock_irqrestore(&host->lock, flags);
647 		return;
648 	}
649 
650 	if (!host->req) {
651 		spin_unlock_irqrestore(&host->lock, flags);
652 		return;
653 	}
654 
655 	req = host->req;
656 	if (!req->stop)
657 		host->req = NULL; /* we will handle finish req below */
658 
659 	data_error = mxcmci_finish_data(host, stat);
660 
661 	spin_unlock_irqrestore(&host->lock, flags);
662 
663 	if (data_error)
664 		return;
665 
666 	mxcmci_read_response(host, stat);
667 	host->cmd = NULL;
668 
669 	if (req->stop) {
670 		if (mxcmci_start_cmd(host, req->stop, 0)) {
671 			mxcmci_finish_request(host, req);
672 			return;
673 		}
674 	} else {
675 		mxcmci_finish_request(host, req);
676 	}
677 }
678 
679 static void mxcmci_cmd_done(struct mxcmci_host *host, unsigned int stat)
680 {
681 	mxcmci_read_response(host, stat);
682 	host->cmd = NULL;
683 
684 	if (!host->data && host->req) {
685 		mxcmci_finish_request(host, host->req);
686 		return;
687 	}
688 
689 	/* For the DMA case the DMA engine handles the data transfer
690 	 * automatically. For non DMA we have to do it ourselves.
691 	 * Don't do it in interrupt context though.
692 	 */
693 	if (!mxcmci_use_dma(host) && host->data)
694 		schedule_work(&host->datawork);
695 
696 }
697 
698 static irqreturn_t mxcmci_irq(int irq, void *devid)
699 {
700 	struct mxcmci_host *host = devid;
701 	bool sdio_irq;
702 	u32 stat;
703 
704 	stat = mxcmci_readl(host, MMC_REG_STATUS);
705 	mxcmci_writel(host,
706 		stat & ~(STATUS_SDIO_INT_ACTIVE | STATUS_DATA_TRANS_DONE |
707 			 STATUS_WRITE_OP_DONE),
708 		MMC_REG_STATUS);
709 
710 	dev_dbg(mmc_dev(host->mmc), "%s: 0x%08x\n", __func__, stat);
711 
712 	spin_lock(&host->lock);
713 	sdio_irq = (stat & STATUS_SDIO_INT_ACTIVE) && host->use_sdio;
714 	spin_unlock(&host->lock);
715 
716 	if (mxcmci_use_dma(host) && (stat & (STATUS_WRITE_OP_DONE)))
717 		mxcmci_writel(host, STATUS_WRITE_OP_DONE, MMC_REG_STATUS);
718 
719 	if (sdio_irq) {
720 		mxcmci_writel(host, STATUS_SDIO_INT_ACTIVE, MMC_REG_STATUS);
721 		mmc_signal_sdio_irq(host->mmc);
722 	}
723 
724 	if (stat & STATUS_END_CMD_RESP)
725 		mxcmci_cmd_done(host, stat);
726 
727 	if (mxcmci_use_dma(host) && (stat & STATUS_WRITE_OP_DONE)) {
728 		del_timer(&host->watchdog);
729 		mxcmci_data_done(host, stat);
730 	}
731 
732 	if (host->default_irq_mask &&
733 		  (stat & (STATUS_CARD_INSERTION | STATUS_CARD_REMOVAL)))
734 		mmc_detect_change(host->mmc, msecs_to_jiffies(200));
735 
736 	return IRQ_HANDLED;
737 }
738 
739 static void mxcmci_request(struct mmc_host *mmc, struct mmc_request *req)
740 {
741 	struct mxcmci_host *host = mmc_priv(mmc);
742 	unsigned int cmdat = host->cmdat;
743 	int error;
744 
745 	WARN_ON(host->req != NULL);
746 
747 	host->req = req;
748 	host->cmdat &= ~CMD_DAT_CONT_INIT;
749 
750 	if (host->dma)
751 		host->do_dma = 1;
752 
753 	if (req->data) {
754 		error = mxcmci_setup_data(host, req->data);
755 		if (error) {
756 			req->cmd->error = error;
757 			goto out;
758 		}
759 
760 
761 		cmdat |= CMD_DAT_CONT_DATA_ENABLE;
762 
763 		if (req->data->flags & MMC_DATA_WRITE)
764 			cmdat |= CMD_DAT_CONT_WRITE;
765 	}
766 
767 	error = mxcmci_start_cmd(host, req->cmd, cmdat);
768 
769 out:
770 	if (error)
771 		mxcmci_finish_request(host, req);
772 }
773 
774 static void mxcmci_set_clk_rate(struct mxcmci_host *host, unsigned int clk_ios)
775 {
776 	unsigned int divider;
777 	int prescaler = 0;
778 	unsigned int clk_in = clk_get_rate(host->clk_per);
779 
780 	while (prescaler <= 0x800) {
781 		for (divider = 1; divider <= 0xF; divider++) {
782 			int x;
783 
784 			x = (clk_in / (divider + 1));
785 
786 			if (prescaler)
787 				x /= (prescaler * 2);
788 
789 			if (x <= clk_ios)
790 				break;
791 		}
792 		if (divider < 0x10)
793 			break;
794 
795 		if (prescaler == 0)
796 			prescaler = 1;
797 		else
798 			prescaler <<= 1;
799 	}
800 
801 	mxcmci_writew(host, (prescaler << 4) | divider, MMC_REG_CLK_RATE);
802 
803 	dev_dbg(mmc_dev(host->mmc), "scaler: %d divider: %d in: %d out: %d\n",
804 			prescaler, divider, clk_in, clk_ios);
805 }
806 
807 static int mxcmci_setup_dma(struct mmc_host *mmc)
808 {
809 	struct mxcmci_host *host = mmc_priv(mmc);
810 	struct dma_slave_config *config = &host->dma_slave_config;
811 
812 	config->dst_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
813 	config->src_addr = host->phys_base + MMC_REG_BUFFER_ACCESS;
814 	config->dst_addr_width = 4;
815 	config->src_addr_width = 4;
816 	config->dst_maxburst = host->burstlen;
817 	config->src_maxburst = host->burstlen;
818 	config->device_fc = false;
819 
820 	return dmaengine_slave_config(host->dma, config);
821 }
822 
823 static void mxcmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
824 {
825 	struct mxcmci_host *host = mmc_priv(mmc);
826 	int burstlen, ret;
827 
828 	/*
829 	 * use burstlen of 64 (16 words) in 4 bit mode (--> reg value  0)
830 	 * use burstlen of 16 (4 words) in 1 bit mode (--> reg value 16)
831 	 */
832 	if (ios->bus_width == MMC_BUS_WIDTH_4)
833 		burstlen = 16;
834 	else
835 		burstlen = 4;
836 
837 	if (mxcmci_use_dma(host) && burstlen != host->burstlen) {
838 		host->burstlen = burstlen;
839 		ret = mxcmci_setup_dma(mmc);
840 		if (ret) {
841 			dev_err(mmc_dev(host->mmc),
842 				"failed to config DMA channel. Falling back to PIO\n");
843 			dma_release_channel(host->dma);
844 			host->do_dma = 0;
845 			host->dma = NULL;
846 		}
847 	}
848 
849 	if (ios->bus_width == MMC_BUS_WIDTH_4)
850 		host->cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
851 	else
852 		host->cmdat &= ~CMD_DAT_CONT_BUS_WIDTH_4;
853 
854 	if (host->power_mode != ios->power_mode) {
855 		host->power_mode = ios->power_mode;
856 		mxcmci_set_power(host, ios->vdd);
857 
858 		if (ios->power_mode == MMC_POWER_ON)
859 			host->cmdat |= CMD_DAT_CONT_INIT;
860 	}
861 
862 	if (ios->clock) {
863 		mxcmci_set_clk_rate(host, ios->clock);
864 		mxcmci_writew(host, STR_STP_CLK_START_CLK, MMC_REG_STR_STP_CLK);
865 	} else {
866 		mxcmci_writew(host, STR_STP_CLK_STOP_CLK, MMC_REG_STR_STP_CLK);
867 	}
868 
869 	host->clock = ios->clock;
870 }
871 
872 static irqreturn_t mxcmci_detect_irq(int irq, void *data)
873 {
874 	struct mmc_host *mmc = data;
875 
876 	dev_dbg(mmc_dev(mmc), "%s\n", __func__);
877 
878 	mmc_detect_change(mmc, msecs_to_jiffies(250));
879 	return IRQ_HANDLED;
880 }
881 
882 static int mxcmci_get_ro(struct mmc_host *mmc)
883 {
884 	struct mxcmci_host *host = mmc_priv(mmc);
885 
886 	if (host->pdata && host->pdata->get_ro)
887 		return !!host->pdata->get_ro(mmc_dev(mmc));
888 	/*
889 	 * If board doesn't support read only detection (no mmc_gpio
890 	 * context or gpio is invalid), then let the mmc core decide
891 	 * what to do.
892 	 */
893 	return mmc_gpio_get_ro(mmc);
894 }
895 
896 static void mxcmci_enable_sdio_irq(struct mmc_host *mmc, int enable)
897 {
898 	struct mxcmci_host *host = mmc_priv(mmc);
899 	unsigned long flags;
900 	u32 int_cntr;
901 
902 	spin_lock_irqsave(&host->lock, flags);
903 	host->use_sdio = enable;
904 	int_cntr = mxcmci_readl(host, MMC_REG_INT_CNTR);
905 
906 	if (enable)
907 		int_cntr |= INT_SDIO_IRQ_EN;
908 	else
909 		int_cntr &= ~INT_SDIO_IRQ_EN;
910 
911 	mxcmci_writel(host, int_cntr, MMC_REG_INT_CNTR);
912 	spin_unlock_irqrestore(&host->lock, flags);
913 }
914 
915 static void mxcmci_init_card(struct mmc_host *host, struct mmc_card *card)
916 {
917 	struct mxcmci_host *mxcmci = mmc_priv(host);
918 
919 	/*
920 	 * MX3 SoCs have a silicon bug which corrupts CRC calculation of
921 	 * multi-block transfers when connected SDIO peripheral doesn't
922 	 * drive the BUSY line as required by the specs.
923 	 * One way to prevent this is to only allow 1-bit transfers.
924 	 */
925 
926 	if (is_imx31_mmc(mxcmci) && card->type == MMC_TYPE_SDIO)
927 		host->caps &= ~MMC_CAP_4_BIT_DATA;
928 	else
929 		host->caps |= MMC_CAP_4_BIT_DATA;
930 }
931 
932 static bool filter(struct dma_chan *chan, void *param)
933 {
934 	struct mxcmci_host *host = param;
935 
936 	if (!imx_dma_is_general_purpose(chan))
937 		return false;
938 
939 	chan->private = &host->dma_data;
940 
941 	return true;
942 }
943 
944 static void mxcmci_watchdog(struct timer_list *t)
945 {
946 	struct mxcmci_host *host = from_timer(host, t, watchdog);
947 	struct mmc_request *req = host->req;
948 	unsigned int stat = mxcmci_readl(host, MMC_REG_STATUS);
949 
950 	if (host->dma_dir == DMA_FROM_DEVICE) {
951 		dmaengine_terminate_all(host->dma);
952 		dev_err(mmc_dev(host->mmc),
953 			"%s: read time out (status = 0x%08x)\n",
954 			__func__, stat);
955 	} else {
956 		dev_err(mmc_dev(host->mmc),
957 			"%s: write time out (status = 0x%08x)\n",
958 			__func__, stat);
959 		mxcmci_softreset(host);
960 	}
961 
962 	/* Mark transfer as erroneus and inform the upper layers */
963 
964 	if (host->data)
965 		host->data->error = -ETIMEDOUT;
966 	host->req = NULL;
967 	host->cmd = NULL;
968 	host->data = NULL;
969 	mmc_request_done(host->mmc, req);
970 }
971 
972 static const struct mmc_host_ops mxcmci_ops = {
973 	.request		= mxcmci_request,
974 	.set_ios		= mxcmci_set_ios,
975 	.get_ro			= mxcmci_get_ro,
976 	.enable_sdio_irq	= mxcmci_enable_sdio_irq,
977 	.init_card		= mxcmci_init_card,
978 };
979 
980 static int mxcmci_probe(struct platform_device *pdev)
981 {
982 	struct mmc_host *mmc;
983 	struct mxcmci_host *host;
984 	struct resource *res;
985 	int ret = 0, irq;
986 	bool dat3_card_detect = false;
987 	dma_cap_mask_t mask;
988 	struct imxmmc_platform_data *pdata = pdev->dev.platform_data;
989 
990 	pr_info("i.MX/MPC512x SDHC driver\n");
991 
992 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
993 	irq = platform_get_irq(pdev, 0);
994 	if (irq < 0)
995 		return irq;
996 
997 	mmc = mmc_alloc_host(sizeof(*host), &pdev->dev);
998 	if (!mmc)
999 		return -ENOMEM;
1000 
1001 	host = mmc_priv(mmc);
1002 
1003 	host->base = devm_ioremap_resource(&pdev->dev, res);
1004 	if (IS_ERR(host->base)) {
1005 		ret = PTR_ERR(host->base);
1006 		goto out_free;
1007 	}
1008 
1009 	host->phys_base = res->start;
1010 
1011 	ret = mmc_of_parse(mmc);
1012 	if (ret)
1013 		goto out_free;
1014 	mmc->ops = &mxcmci_ops;
1015 
1016 	/* For devicetree parsing, the bus width is read from devicetree */
1017 	if (pdata)
1018 		mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1019 	else
1020 		mmc->caps |= MMC_CAP_SDIO_IRQ;
1021 
1022 	/* MMC core transfer sizes tunable parameters */
1023 	mmc->max_blk_size = 2048;
1024 	mmc->max_blk_count = 65535;
1025 	mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
1026 	mmc->max_seg_size = mmc->max_req_size;
1027 
1028 	host->devtype = (enum mxcmci_type)of_device_get_match_data(&pdev->dev);
1029 
1030 	/* adjust max_segs after devtype detection */
1031 	if (!is_mpc512x_mmc(host))
1032 		mmc->max_segs = 64;
1033 
1034 	host->mmc = mmc;
1035 	host->pdata = pdata;
1036 	spin_lock_init(&host->lock);
1037 
1038 	if (pdata)
1039 		dat3_card_detect = pdata->dat3_card_detect;
1040 	else if (mmc_card_is_removable(mmc)
1041 			&& !of_property_read_bool(pdev->dev.of_node, "cd-gpios"))
1042 		dat3_card_detect = true;
1043 
1044 	ret = mmc_regulator_get_supply(mmc);
1045 	if (ret)
1046 		goto out_free;
1047 
1048 	if (!mmc->ocr_avail) {
1049 		if (pdata && pdata->ocr_avail)
1050 			mmc->ocr_avail = pdata->ocr_avail;
1051 		else
1052 			mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1053 	}
1054 
1055 	if (dat3_card_detect)
1056 		host->default_irq_mask =
1057 			INT_CARD_INSERTION_EN | INT_CARD_REMOVAL_EN;
1058 	else
1059 		host->default_irq_mask = 0;
1060 
1061 	host->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
1062 	if (IS_ERR(host->clk_ipg)) {
1063 		ret = PTR_ERR(host->clk_ipg);
1064 		goto out_free;
1065 	}
1066 
1067 	host->clk_per = devm_clk_get(&pdev->dev, "per");
1068 	if (IS_ERR(host->clk_per)) {
1069 		ret = PTR_ERR(host->clk_per);
1070 		goto out_free;
1071 	}
1072 
1073 	ret = clk_prepare_enable(host->clk_per);
1074 	if (ret)
1075 		goto out_free;
1076 
1077 	ret = clk_prepare_enable(host->clk_ipg);
1078 	if (ret)
1079 		goto out_clk_per_put;
1080 
1081 	mxcmci_softreset(host);
1082 
1083 	host->rev_no = mxcmci_readw(host, MMC_REG_REV_NO);
1084 	if (host->rev_no != 0x400) {
1085 		ret = -ENODEV;
1086 		dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
1087 			host->rev_no);
1088 		goto out_clk_put;
1089 	}
1090 
1091 	mmc->f_min = clk_get_rate(host->clk_per) >> 16;
1092 	mmc->f_max = clk_get_rate(host->clk_per) >> 1;
1093 
1094 	/* recommended in data sheet */
1095 	mxcmci_writew(host, 0x2db4, MMC_REG_READ_TO);
1096 
1097 	mxcmci_writel(host, host->default_irq_mask, MMC_REG_INT_CNTR);
1098 
1099 	if (!host->pdata) {
1100 		host->dma = dma_request_chan(&pdev->dev, "rx-tx");
1101 		if (IS_ERR(host->dma)) {
1102 			if (PTR_ERR(host->dma) == -EPROBE_DEFER) {
1103 				ret = -EPROBE_DEFER;
1104 				goto out_clk_put;
1105 			}
1106 
1107 			/* Ignore errors to fall back to PIO mode */
1108 			host->dma = NULL;
1109 		}
1110 	} else {
1111 		res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1112 		if (res) {
1113 			host->dmareq = res->start;
1114 			host->dma_data.peripheral_type = IMX_DMATYPE_SDHC;
1115 			host->dma_data.priority = DMA_PRIO_LOW;
1116 			host->dma_data.dma_request = host->dmareq;
1117 			dma_cap_zero(mask);
1118 			dma_cap_set(DMA_SLAVE, mask);
1119 			host->dma = dma_request_channel(mask, filter, host);
1120 		}
1121 	}
1122 	if (host->dma)
1123 		mmc->max_seg_size = dma_get_max_seg_size(
1124 				host->dma->device->dev);
1125 	else
1126 		dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");
1127 
1128 	INIT_WORK(&host->datawork, mxcmci_datawork);
1129 
1130 	ret = devm_request_irq(&pdev->dev, irq, mxcmci_irq, 0,
1131 			       dev_name(&pdev->dev), host);
1132 	if (ret)
1133 		goto out_free_dma;
1134 
1135 	platform_set_drvdata(pdev, mmc);
1136 
1137 	if (host->pdata && host->pdata->init) {
1138 		ret = host->pdata->init(&pdev->dev, mxcmci_detect_irq,
1139 				host->mmc);
1140 		if (ret)
1141 			goto out_free_dma;
1142 	}
1143 
1144 	timer_setup(&host->watchdog, mxcmci_watchdog, 0);
1145 
1146 	mmc_add_host(mmc);
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 int 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 	return 0;
1184 }
1185 
1186 #ifdef CONFIG_PM_SLEEP
1187 static int mxcmci_suspend(struct device *dev)
1188 {
1189 	struct mmc_host *mmc = dev_get_drvdata(dev);
1190 	struct mxcmci_host *host = mmc_priv(mmc);
1191 
1192 	clk_disable_unprepare(host->clk_per);
1193 	clk_disable_unprepare(host->clk_ipg);
1194 	return 0;
1195 }
1196 
1197 static int mxcmci_resume(struct device *dev)
1198 {
1199 	struct mmc_host *mmc = dev_get_drvdata(dev);
1200 	struct mxcmci_host *host = mmc_priv(mmc);
1201 	int ret;
1202 
1203 	ret = clk_prepare_enable(host->clk_per);
1204 	if (ret)
1205 		return ret;
1206 
1207 	ret = clk_prepare_enable(host->clk_ipg);
1208 	if (ret)
1209 		clk_disable_unprepare(host->clk_per);
1210 
1211 	return ret;
1212 }
1213 #endif
1214 
1215 static SIMPLE_DEV_PM_OPS(mxcmci_pm_ops, mxcmci_suspend, mxcmci_resume);
1216 
1217 static struct platform_driver mxcmci_driver = {
1218 	.probe		= mxcmci_probe,
1219 	.remove		= mxcmci_remove,
1220 	.driver		= {
1221 		.name		= DRIVER_NAME,
1222 		.probe_type	= PROBE_PREFER_ASYNCHRONOUS,
1223 		.pm	= &mxcmci_pm_ops,
1224 		.of_match_table	= mxcmci_of_match,
1225 	}
1226 };
1227 
1228 module_platform_driver(mxcmci_driver);
1229 
1230 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1231 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1232 MODULE_LICENSE("GPL");
1233 MODULE_ALIAS("platform:mxc-mmc");
1234