xref: /openbmc/linux/drivers/mmc/host/dw_mmc.c (revision e4781421e883340b796da5a724bda7226817990b)
1 /*
2  * Synopsys DesignWare Multimedia Card Interface driver
3  *  (Based on NXP driver for lpc 31xx)
4  *
5  * Copyright (C) 2009 NXP Semiconductors
6  * Copyright (C) 2009, 2010 Imagination Technologies Ltd.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 #include <linux/blkdev.h>
15 #include <linux/clk.h>
16 #include <linux/debugfs.h>
17 #include <linux/device.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/err.h>
20 #include <linux/init.h>
21 #include <linux/interrupt.h>
22 #include <linux/ioport.h>
23 #include <linux/module.h>
24 #include <linux/platform_device.h>
25 #include <linux/seq_file.h>
26 #include <linux/slab.h>
27 #include <linux/stat.h>
28 #include <linux/delay.h>
29 #include <linux/irq.h>
30 #include <linux/mmc/card.h>
31 #include <linux/mmc/host.h>
32 #include <linux/mmc/mmc.h>
33 #include <linux/mmc/sd.h>
34 #include <linux/mmc/sdio.h>
35 #include <linux/mmc/dw_mmc.h>
36 #include <linux/bitops.h>
37 #include <linux/regulator/consumer.h>
38 #include <linux/of.h>
39 #include <linux/of_gpio.h>
40 #include <linux/mmc/slot-gpio.h>
41 
42 #include "dw_mmc.h"
43 
44 /* Common flag combinations */
45 #define DW_MCI_DATA_ERROR_FLAGS	(SDMMC_INT_DRTO | SDMMC_INT_DCRC | \
46 				 SDMMC_INT_HTO | SDMMC_INT_SBE  | \
47 				 SDMMC_INT_EBE | SDMMC_INT_HLE)
48 #define DW_MCI_CMD_ERROR_FLAGS	(SDMMC_INT_RTO | SDMMC_INT_RCRC | \
49 				 SDMMC_INT_RESP_ERR | SDMMC_INT_HLE)
50 #define DW_MCI_ERROR_FLAGS	(DW_MCI_DATA_ERROR_FLAGS | \
51 				 DW_MCI_CMD_ERROR_FLAGS)
52 #define DW_MCI_SEND_STATUS	1
53 #define DW_MCI_RECV_STATUS	2
54 #define DW_MCI_DMA_THRESHOLD	16
55 
56 #define DW_MCI_FREQ_MAX	200000000	/* unit: HZ */
57 #define DW_MCI_FREQ_MIN	100000		/* unit: HZ */
58 
59 #define IDMAC_INT_CLR		(SDMMC_IDMAC_INT_AI | SDMMC_IDMAC_INT_NI | \
60 				 SDMMC_IDMAC_INT_CES | SDMMC_IDMAC_INT_DU | \
61 				 SDMMC_IDMAC_INT_FBE | SDMMC_IDMAC_INT_RI | \
62 				 SDMMC_IDMAC_INT_TI)
63 
64 #define DESC_RING_BUF_SZ	PAGE_SIZE
65 
66 struct idmac_desc_64addr {
67 	u32		des0;	/* Control Descriptor */
68 
69 	u32		des1;	/* Reserved */
70 
71 	u32		des2;	/*Buffer sizes */
72 #define IDMAC_64ADDR_SET_BUFFER1_SIZE(d, s) \
73 	((d)->des2 = ((d)->des2 & cpu_to_le32(0x03ffe000)) | \
74 	 ((cpu_to_le32(s)) & cpu_to_le32(0x1fff)))
75 
76 	u32		des3;	/* Reserved */
77 
78 	u32		des4;	/* Lower 32-bits of Buffer Address Pointer 1*/
79 	u32		des5;	/* Upper 32-bits of Buffer Address Pointer 1*/
80 
81 	u32		des6;	/* Lower 32-bits of Next Descriptor Address */
82 	u32		des7;	/* Upper 32-bits of Next Descriptor Address */
83 };
84 
85 struct idmac_desc {
86 	__le32		des0;	/* Control Descriptor */
87 #define IDMAC_DES0_DIC	BIT(1)
88 #define IDMAC_DES0_LD	BIT(2)
89 #define IDMAC_DES0_FD	BIT(3)
90 #define IDMAC_DES0_CH	BIT(4)
91 #define IDMAC_DES0_ER	BIT(5)
92 #define IDMAC_DES0_CES	BIT(30)
93 #define IDMAC_DES0_OWN	BIT(31)
94 
95 	__le32		des1;	/* Buffer sizes */
96 #define IDMAC_SET_BUFFER1_SIZE(d, s) \
97 	((d)->des1 = ((d)->des1 & cpu_to_le32(0x03ffe000)) | (cpu_to_le32((s) & 0x1fff)))
98 
99 	__le32		des2;	/* buffer 1 physical address */
100 
101 	__le32		des3;	/* buffer 2 physical address */
102 };
103 
104 /* Each descriptor can transfer up to 4KB of data in chained mode */
105 #define DW_MCI_DESC_DATA_LENGTH	0x1000
106 
107 static bool dw_mci_reset(struct dw_mci *host);
108 static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset);
109 static int dw_mci_card_busy(struct mmc_host *mmc);
110 static int dw_mci_get_cd(struct mmc_host *mmc);
111 
112 #if defined(CONFIG_DEBUG_FS)
113 static int dw_mci_req_show(struct seq_file *s, void *v)
114 {
115 	struct dw_mci_slot *slot = s->private;
116 	struct mmc_request *mrq;
117 	struct mmc_command *cmd;
118 	struct mmc_command *stop;
119 	struct mmc_data	*data;
120 
121 	/* Make sure we get a consistent snapshot */
122 	spin_lock_bh(&slot->host->lock);
123 	mrq = slot->mrq;
124 
125 	if (mrq) {
126 		cmd = mrq->cmd;
127 		data = mrq->data;
128 		stop = mrq->stop;
129 
130 		if (cmd)
131 			seq_printf(s,
132 				   "CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
133 				   cmd->opcode, cmd->arg, cmd->flags,
134 				   cmd->resp[0], cmd->resp[1], cmd->resp[2],
135 				   cmd->resp[2], cmd->error);
136 		if (data)
137 			seq_printf(s, "DATA %u / %u * %u flg %x err %d\n",
138 				   data->bytes_xfered, data->blocks,
139 				   data->blksz, data->flags, data->error);
140 		if (stop)
141 			seq_printf(s,
142 				   "CMD%u(0x%x) flg %x rsp %x %x %x %x err %d\n",
143 				   stop->opcode, stop->arg, stop->flags,
144 				   stop->resp[0], stop->resp[1], stop->resp[2],
145 				   stop->resp[2], stop->error);
146 	}
147 
148 	spin_unlock_bh(&slot->host->lock);
149 
150 	return 0;
151 }
152 
153 static int dw_mci_req_open(struct inode *inode, struct file *file)
154 {
155 	return single_open(file, dw_mci_req_show, inode->i_private);
156 }
157 
158 static const struct file_operations dw_mci_req_fops = {
159 	.owner		= THIS_MODULE,
160 	.open		= dw_mci_req_open,
161 	.read		= seq_read,
162 	.llseek		= seq_lseek,
163 	.release	= single_release,
164 };
165 
166 static int dw_mci_regs_show(struct seq_file *s, void *v)
167 {
168 	struct dw_mci *host = s->private;
169 
170 	seq_printf(s, "STATUS:\t0x%08x\n", mci_readl(host, STATUS));
171 	seq_printf(s, "RINTSTS:\t0x%08x\n", mci_readl(host, RINTSTS));
172 	seq_printf(s, "CMD:\t0x%08x\n", mci_readl(host, CMD));
173 	seq_printf(s, "CTRL:\t0x%08x\n", mci_readl(host, CTRL));
174 	seq_printf(s, "INTMASK:\t0x%08x\n", mci_readl(host, INTMASK));
175 	seq_printf(s, "CLKENA:\t0x%08x\n", mci_readl(host, CLKENA));
176 
177 	return 0;
178 }
179 
180 static int dw_mci_regs_open(struct inode *inode, struct file *file)
181 {
182 	return single_open(file, dw_mci_regs_show, inode->i_private);
183 }
184 
185 static const struct file_operations dw_mci_regs_fops = {
186 	.owner		= THIS_MODULE,
187 	.open		= dw_mci_regs_open,
188 	.read		= seq_read,
189 	.llseek		= seq_lseek,
190 	.release	= single_release,
191 };
192 
193 static void dw_mci_init_debugfs(struct dw_mci_slot *slot)
194 {
195 	struct mmc_host	*mmc = slot->mmc;
196 	struct dw_mci *host = slot->host;
197 	struct dentry *root;
198 	struct dentry *node;
199 
200 	root = mmc->debugfs_root;
201 	if (!root)
202 		return;
203 
204 	node = debugfs_create_file("regs", S_IRUSR, root, host,
205 				   &dw_mci_regs_fops);
206 	if (!node)
207 		goto err;
208 
209 	node = debugfs_create_file("req", S_IRUSR, root, slot,
210 				   &dw_mci_req_fops);
211 	if (!node)
212 		goto err;
213 
214 	node = debugfs_create_u32("state", S_IRUSR, root, (u32 *)&host->state);
215 	if (!node)
216 		goto err;
217 
218 	node = debugfs_create_x32("pending_events", S_IRUSR, root,
219 				  (u32 *)&host->pending_events);
220 	if (!node)
221 		goto err;
222 
223 	node = debugfs_create_x32("completed_events", S_IRUSR, root,
224 				  (u32 *)&host->completed_events);
225 	if (!node)
226 		goto err;
227 
228 	return;
229 
230 err:
231 	dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
232 }
233 #endif /* defined(CONFIG_DEBUG_FS) */
234 
235 static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg);
236 
237 static u32 dw_mci_prepare_command(struct mmc_host *mmc, struct mmc_command *cmd)
238 {
239 	struct dw_mci_slot *slot = mmc_priv(mmc);
240 	struct dw_mci *host = slot->host;
241 	u32 cmdr;
242 
243 	cmd->error = -EINPROGRESS;
244 	cmdr = cmd->opcode;
245 
246 	if (cmd->opcode == MMC_STOP_TRANSMISSION ||
247 	    cmd->opcode == MMC_GO_IDLE_STATE ||
248 	    cmd->opcode == MMC_GO_INACTIVE_STATE ||
249 	    (cmd->opcode == SD_IO_RW_DIRECT &&
250 	     ((cmd->arg >> 9) & 0x1FFFF) == SDIO_CCCR_ABORT))
251 		cmdr |= SDMMC_CMD_STOP;
252 	else if (cmd->opcode != MMC_SEND_STATUS && cmd->data)
253 		cmdr |= SDMMC_CMD_PRV_DAT_WAIT;
254 
255 	if (cmd->opcode == SD_SWITCH_VOLTAGE) {
256 		u32 clk_en_a;
257 
258 		/* Special bit makes CMD11 not die */
259 		cmdr |= SDMMC_CMD_VOLT_SWITCH;
260 
261 		/* Change state to continue to handle CMD11 weirdness */
262 		WARN_ON(slot->host->state != STATE_SENDING_CMD);
263 		slot->host->state = STATE_SENDING_CMD11;
264 
265 		/*
266 		 * We need to disable low power mode (automatic clock stop)
267 		 * while doing voltage switch so we don't confuse the card,
268 		 * since stopping the clock is a specific part of the UHS
269 		 * voltage change dance.
270 		 *
271 		 * Note that low power mode (SDMMC_CLKEN_LOW_PWR) will be
272 		 * unconditionally turned back on in dw_mci_setup_bus() if it's
273 		 * ever called with a non-zero clock.  That shouldn't happen
274 		 * until the voltage change is all done.
275 		 */
276 		clk_en_a = mci_readl(host, CLKENA);
277 		clk_en_a &= ~(SDMMC_CLKEN_LOW_PWR << slot->id);
278 		mci_writel(host, CLKENA, clk_en_a);
279 		mci_send_cmd(slot, SDMMC_CMD_UPD_CLK |
280 			     SDMMC_CMD_PRV_DAT_WAIT, 0);
281 	}
282 
283 	if (cmd->flags & MMC_RSP_PRESENT) {
284 		/* We expect a response, so set this bit */
285 		cmdr |= SDMMC_CMD_RESP_EXP;
286 		if (cmd->flags & MMC_RSP_136)
287 			cmdr |= SDMMC_CMD_RESP_LONG;
288 	}
289 
290 	if (cmd->flags & MMC_RSP_CRC)
291 		cmdr |= SDMMC_CMD_RESP_CRC;
292 
293 	if (cmd->data) {
294 		cmdr |= SDMMC_CMD_DAT_EXP;
295 		if (cmd->data->flags & MMC_DATA_WRITE)
296 			cmdr |= SDMMC_CMD_DAT_WR;
297 	}
298 
299 	if (!test_bit(DW_MMC_CARD_NO_USE_HOLD, &slot->flags))
300 		cmdr |= SDMMC_CMD_USE_HOLD_REG;
301 
302 	return cmdr;
303 }
304 
305 static u32 dw_mci_prep_stop_abort(struct dw_mci *host, struct mmc_command *cmd)
306 {
307 	struct mmc_command *stop;
308 	u32 cmdr;
309 
310 	if (!cmd->data)
311 		return 0;
312 
313 	stop = &host->stop_abort;
314 	cmdr = cmd->opcode;
315 	memset(stop, 0, sizeof(struct mmc_command));
316 
317 	if (cmdr == MMC_READ_SINGLE_BLOCK ||
318 	    cmdr == MMC_READ_MULTIPLE_BLOCK ||
319 	    cmdr == MMC_WRITE_BLOCK ||
320 	    cmdr == MMC_WRITE_MULTIPLE_BLOCK ||
321 	    cmdr == MMC_SEND_TUNING_BLOCK ||
322 	    cmdr == MMC_SEND_TUNING_BLOCK_HS200) {
323 		stop->opcode = MMC_STOP_TRANSMISSION;
324 		stop->arg = 0;
325 		stop->flags = MMC_RSP_R1B | MMC_CMD_AC;
326 	} else if (cmdr == SD_IO_RW_EXTENDED) {
327 		stop->opcode = SD_IO_RW_DIRECT;
328 		stop->arg |= (1 << 31) | (0 << 28) | (SDIO_CCCR_ABORT << 9) |
329 			     ((cmd->arg >> 28) & 0x7);
330 		stop->flags = MMC_RSP_SPI_R5 | MMC_RSP_R5 | MMC_CMD_AC;
331 	} else {
332 		return 0;
333 	}
334 
335 	cmdr = stop->opcode | SDMMC_CMD_STOP |
336 		SDMMC_CMD_RESP_CRC | SDMMC_CMD_RESP_EXP;
337 
338 	if (!test_bit(DW_MMC_CARD_NO_USE_HOLD, &host->cur_slot->flags))
339 		cmdr |= SDMMC_CMD_USE_HOLD_REG;
340 
341 	return cmdr;
342 }
343 
344 static void dw_mci_wait_while_busy(struct dw_mci *host, u32 cmd_flags)
345 {
346 	unsigned long timeout = jiffies + msecs_to_jiffies(500);
347 
348 	/*
349 	 * Databook says that before issuing a new data transfer command
350 	 * we need to check to see if the card is busy.  Data transfer commands
351 	 * all have SDMMC_CMD_PRV_DAT_WAIT set, so we'll key off that.
352 	 *
353 	 * ...also allow sending for SDMMC_CMD_VOLT_SWITCH where busy is
354 	 * expected.
355 	 */
356 	if ((cmd_flags & SDMMC_CMD_PRV_DAT_WAIT) &&
357 	    !(cmd_flags & SDMMC_CMD_VOLT_SWITCH)) {
358 		while (mci_readl(host, STATUS) & SDMMC_STATUS_BUSY) {
359 			if (time_after(jiffies, timeout)) {
360 				/* Command will fail; we'll pass error then */
361 				dev_err(host->dev, "Busy; trying anyway\n");
362 				break;
363 			}
364 			udelay(10);
365 		}
366 	}
367 }
368 
369 static void dw_mci_start_command(struct dw_mci *host,
370 				 struct mmc_command *cmd, u32 cmd_flags)
371 {
372 	host->cmd = cmd;
373 	dev_vdbg(host->dev,
374 		 "start command: ARGR=0x%08x CMDR=0x%08x\n",
375 		 cmd->arg, cmd_flags);
376 
377 	mci_writel(host, CMDARG, cmd->arg);
378 	wmb(); /* drain writebuffer */
379 	dw_mci_wait_while_busy(host, cmd_flags);
380 
381 	mci_writel(host, CMD, cmd_flags | SDMMC_CMD_START);
382 }
383 
384 static inline void send_stop_abort(struct dw_mci *host, struct mmc_data *data)
385 {
386 	struct mmc_command *stop = &host->stop_abort;
387 
388 	dw_mci_start_command(host, stop, host->stop_cmdr);
389 }
390 
391 /* DMA interface functions */
392 static void dw_mci_stop_dma(struct dw_mci *host)
393 {
394 	if (host->using_dma) {
395 		host->dma_ops->stop(host);
396 		host->dma_ops->cleanup(host);
397 	}
398 
399 	/* Data transfer was stopped by the interrupt handler */
400 	set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
401 }
402 
403 static int dw_mci_get_dma_dir(struct mmc_data *data)
404 {
405 	if (data->flags & MMC_DATA_WRITE)
406 		return DMA_TO_DEVICE;
407 	else
408 		return DMA_FROM_DEVICE;
409 }
410 
411 static void dw_mci_dma_cleanup(struct dw_mci *host)
412 {
413 	struct mmc_data *data = host->data;
414 
415 	if (data && data->host_cookie == COOKIE_MAPPED) {
416 		dma_unmap_sg(host->dev,
417 			     data->sg,
418 			     data->sg_len,
419 			     dw_mci_get_dma_dir(data));
420 		data->host_cookie = COOKIE_UNMAPPED;
421 	}
422 }
423 
424 static void dw_mci_idmac_reset(struct dw_mci *host)
425 {
426 	u32 bmod = mci_readl(host, BMOD);
427 	/* Software reset of DMA */
428 	bmod |= SDMMC_IDMAC_SWRESET;
429 	mci_writel(host, BMOD, bmod);
430 }
431 
432 static void dw_mci_idmac_stop_dma(struct dw_mci *host)
433 {
434 	u32 temp;
435 
436 	/* Disable and reset the IDMAC interface */
437 	temp = mci_readl(host, CTRL);
438 	temp &= ~SDMMC_CTRL_USE_IDMAC;
439 	temp |= SDMMC_CTRL_DMA_RESET;
440 	mci_writel(host, CTRL, temp);
441 
442 	/* Stop the IDMAC running */
443 	temp = mci_readl(host, BMOD);
444 	temp &= ~(SDMMC_IDMAC_ENABLE | SDMMC_IDMAC_FB);
445 	temp |= SDMMC_IDMAC_SWRESET;
446 	mci_writel(host, BMOD, temp);
447 }
448 
449 static void dw_mci_dmac_complete_dma(void *arg)
450 {
451 	struct dw_mci *host = arg;
452 	struct mmc_data *data = host->data;
453 
454 	dev_vdbg(host->dev, "DMA complete\n");
455 
456 	if ((host->use_dma == TRANS_MODE_EDMAC) &&
457 	    data && (data->flags & MMC_DATA_READ))
458 		/* Invalidate cache after read */
459 		dma_sync_sg_for_cpu(mmc_dev(host->cur_slot->mmc),
460 				    data->sg,
461 				    data->sg_len,
462 				    DMA_FROM_DEVICE);
463 
464 	host->dma_ops->cleanup(host);
465 
466 	/*
467 	 * If the card was removed, data will be NULL. No point in trying to
468 	 * send the stop command or waiting for NBUSY in this case.
469 	 */
470 	if (data) {
471 		set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
472 		tasklet_schedule(&host->tasklet);
473 	}
474 }
475 
476 static int dw_mci_idmac_init(struct dw_mci *host)
477 {
478 	int i;
479 
480 	if (host->dma_64bit_address == 1) {
481 		struct idmac_desc_64addr *p;
482 		/* Number of descriptors in the ring buffer */
483 		host->ring_size =
484 			DESC_RING_BUF_SZ / sizeof(struct idmac_desc_64addr);
485 
486 		/* Forward link the descriptor list */
487 		for (i = 0, p = host->sg_cpu; i < host->ring_size - 1;
488 								i++, p++) {
489 			p->des6 = (host->sg_dma +
490 					(sizeof(struct idmac_desc_64addr) *
491 							(i + 1))) & 0xffffffff;
492 
493 			p->des7 = (u64)(host->sg_dma +
494 					(sizeof(struct idmac_desc_64addr) *
495 							(i + 1))) >> 32;
496 			/* Initialize reserved and buffer size fields to "0" */
497 			p->des1 = 0;
498 			p->des2 = 0;
499 			p->des3 = 0;
500 		}
501 
502 		/* Set the last descriptor as the end-of-ring descriptor */
503 		p->des6 = host->sg_dma & 0xffffffff;
504 		p->des7 = (u64)host->sg_dma >> 32;
505 		p->des0 = IDMAC_DES0_ER;
506 
507 	} else {
508 		struct idmac_desc *p;
509 		/* Number of descriptors in the ring buffer */
510 		host->ring_size =
511 			DESC_RING_BUF_SZ / sizeof(struct idmac_desc);
512 
513 		/* Forward link the descriptor list */
514 		for (i = 0, p = host->sg_cpu;
515 		     i < host->ring_size - 1;
516 		     i++, p++) {
517 			p->des3 = cpu_to_le32(host->sg_dma +
518 					(sizeof(struct idmac_desc) * (i + 1)));
519 			p->des1 = 0;
520 		}
521 
522 		/* Set the last descriptor as the end-of-ring descriptor */
523 		p->des3 = cpu_to_le32(host->sg_dma);
524 		p->des0 = cpu_to_le32(IDMAC_DES0_ER);
525 	}
526 
527 	dw_mci_idmac_reset(host);
528 
529 	if (host->dma_64bit_address == 1) {
530 		/* Mask out interrupts - get Tx & Rx complete only */
531 		mci_writel(host, IDSTS64, IDMAC_INT_CLR);
532 		mci_writel(host, IDINTEN64, SDMMC_IDMAC_INT_NI |
533 				SDMMC_IDMAC_INT_RI | SDMMC_IDMAC_INT_TI);
534 
535 		/* Set the descriptor base address */
536 		mci_writel(host, DBADDRL, host->sg_dma & 0xffffffff);
537 		mci_writel(host, DBADDRU, (u64)host->sg_dma >> 32);
538 
539 	} else {
540 		/* Mask out interrupts - get Tx & Rx complete only */
541 		mci_writel(host, IDSTS, IDMAC_INT_CLR);
542 		mci_writel(host, IDINTEN, SDMMC_IDMAC_INT_NI |
543 				SDMMC_IDMAC_INT_RI | SDMMC_IDMAC_INT_TI);
544 
545 		/* Set the descriptor base address */
546 		mci_writel(host, DBADDR, host->sg_dma);
547 	}
548 
549 	return 0;
550 }
551 
552 static inline int dw_mci_prepare_desc64(struct dw_mci *host,
553 					 struct mmc_data *data,
554 					 unsigned int sg_len)
555 {
556 	unsigned int desc_len;
557 	struct idmac_desc_64addr *desc_first, *desc_last, *desc;
558 	unsigned long timeout;
559 	int i;
560 
561 	desc_first = desc_last = desc = host->sg_cpu;
562 
563 	for (i = 0; i < sg_len; i++) {
564 		unsigned int length = sg_dma_len(&data->sg[i]);
565 
566 		u64 mem_addr = sg_dma_address(&data->sg[i]);
567 
568 		for ( ; length ; desc++) {
569 			desc_len = (length <= DW_MCI_DESC_DATA_LENGTH) ?
570 				   length : DW_MCI_DESC_DATA_LENGTH;
571 
572 			length -= desc_len;
573 
574 			/*
575 			 * Wait for the former clear OWN bit operation
576 			 * of IDMAC to make sure that this descriptor
577 			 * isn't still owned by IDMAC as IDMAC's write
578 			 * ops and CPU's read ops are asynchronous.
579 			 */
580 			timeout = jiffies + msecs_to_jiffies(100);
581 			while (readl(&desc->des0) & IDMAC_DES0_OWN) {
582 				if (time_after(jiffies, timeout))
583 					goto err_own_bit;
584 				udelay(10);
585 			}
586 
587 			/*
588 			 * Set the OWN bit and disable interrupts
589 			 * for this descriptor
590 			 */
591 			desc->des0 = IDMAC_DES0_OWN | IDMAC_DES0_DIC |
592 						IDMAC_DES0_CH;
593 
594 			/* Buffer length */
595 			IDMAC_64ADDR_SET_BUFFER1_SIZE(desc, desc_len);
596 
597 			/* Physical address to DMA to/from */
598 			desc->des4 = mem_addr & 0xffffffff;
599 			desc->des5 = mem_addr >> 32;
600 
601 			/* Update physical address for the next desc */
602 			mem_addr += desc_len;
603 
604 			/* Save pointer to the last descriptor */
605 			desc_last = desc;
606 		}
607 	}
608 
609 	/* Set first descriptor */
610 	desc_first->des0 |= IDMAC_DES0_FD;
611 
612 	/* Set last descriptor */
613 	desc_last->des0 &= ~(IDMAC_DES0_CH | IDMAC_DES0_DIC);
614 	desc_last->des0 |= IDMAC_DES0_LD;
615 
616 	return 0;
617 err_own_bit:
618 	/* restore the descriptor chain as it's polluted */
619 	dev_dbg(host->dev, "descriptor is still owned by IDMAC.\n");
620 	memset(host->sg_cpu, 0, DESC_RING_BUF_SZ);
621 	dw_mci_idmac_init(host);
622 	return -EINVAL;
623 }
624 
625 
626 static inline int dw_mci_prepare_desc32(struct dw_mci *host,
627 					 struct mmc_data *data,
628 					 unsigned int sg_len)
629 {
630 	unsigned int desc_len;
631 	struct idmac_desc *desc_first, *desc_last, *desc;
632 	unsigned long timeout;
633 	int i;
634 
635 	desc_first = desc_last = desc = host->sg_cpu;
636 
637 	for (i = 0; i < sg_len; i++) {
638 		unsigned int length = sg_dma_len(&data->sg[i]);
639 
640 		u32 mem_addr = sg_dma_address(&data->sg[i]);
641 
642 		for ( ; length ; desc++) {
643 			desc_len = (length <= DW_MCI_DESC_DATA_LENGTH) ?
644 				   length : DW_MCI_DESC_DATA_LENGTH;
645 
646 			length -= desc_len;
647 
648 			/*
649 			 * Wait for the former clear OWN bit operation
650 			 * of IDMAC to make sure that this descriptor
651 			 * isn't still owned by IDMAC as IDMAC's write
652 			 * ops and CPU's read ops are asynchronous.
653 			 */
654 			timeout = jiffies + msecs_to_jiffies(100);
655 			while (readl(&desc->des0) &
656 			       cpu_to_le32(IDMAC_DES0_OWN)) {
657 				if (time_after(jiffies, timeout))
658 					goto err_own_bit;
659 				udelay(10);
660 			}
661 
662 			/*
663 			 * Set the OWN bit and disable interrupts
664 			 * for this descriptor
665 			 */
666 			desc->des0 = cpu_to_le32(IDMAC_DES0_OWN |
667 						 IDMAC_DES0_DIC |
668 						 IDMAC_DES0_CH);
669 
670 			/* Buffer length */
671 			IDMAC_SET_BUFFER1_SIZE(desc, desc_len);
672 
673 			/* Physical address to DMA to/from */
674 			desc->des2 = cpu_to_le32(mem_addr);
675 
676 			/* Update physical address for the next desc */
677 			mem_addr += desc_len;
678 
679 			/* Save pointer to the last descriptor */
680 			desc_last = desc;
681 		}
682 	}
683 
684 	/* Set first descriptor */
685 	desc_first->des0 |= cpu_to_le32(IDMAC_DES0_FD);
686 
687 	/* Set last descriptor */
688 	desc_last->des0 &= cpu_to_le32(~(IDMAC_DES0_CH |
689 				       IDMAC_DES0_DIC));
690 	desc_last->des0 |= cpu_to_le32(IDMAC_DES0_LD);
691 
692 	return 0;
693 err_own_bit:
694 	/* restore the descriptor chain as it's polluted */
695 	dev_dbg(host->dev, "descriptor is still owned by IDMAC.\n");
696 	memset(host->sg_cpu, 0, DESC_RING_BUF_SZ);
697 	dw_mci_idmac_init(host);
698 	return -EINVAL;
699 }
700 
701 static int dw_mci_idmac_start_dma(struct dw_mci *host, unsigned int sg_len)
702 {
703 	u32 temp;
704 	int ret;
705 
706 	if (host->dma_64bit_address == 1)
707 		ret = dw_mci_prepare_desc64(host, host->data, sg_len);
708 	else
709 		ret = dw_mci_prepare_desc32(host, host->data, sg_len);
710 
711 	if (ret)
712 		goto out;
713 
714 	/* drain writebuffer */
715 	wmb();
716 
717 	/* Make sure to reset DMA in case we did PIO before this */
718 	dw_mci_ctrl_reset(host, SDMMC_CTRL_DMA_RESET);
719 	dw_mci_idmac_reset(host);
720 
721 	/* Select IDMAC interface */
722 	temp = mci_readl(host, CTRL);
723 	temp |= SDMMC_CTRL_USE_IDMAC;
724 	mci_writel(host, CTRL, temp);
725 
726 	/* drain writebuffer */
727 	wmb();
728 
729 	/* Enable the IDMAC */
730 	temp = mci_readl(host, BMOD);
731 	temp |= SDMMC_IDMAC_ENABLE | SDMMC_IDMAC_FB;
732 	mci_writel(host, BMOD, temp);
733 
734 	/* Start it running */
735 	mci_writel(host, PLDMND, 1);
736 
737 out:
738 	return ret;
739 }
740 
741 static const struct dw_mci_dma_ops dw_mci_idmac_ops = {
742 	.init = dw_mci_idmac_init,
743 	.start = dw_mci_idmac_start_dma,
744 	.stop = dw_mci_idmac_stop_dma,
745 	.complete = dw_mci_dmac_complete_dma,
746 	.cleanup = dw_mci_dma_cleanup,
747 };
748 
749 static void dw_mci_edmac_stop_dma(struct dw_mci *host)
750 {
751 	dmaengine_terminate_async(host->dms->ch);
752 }
753 
754 static int dw_mci_edmac_start_dma(struct dw_mci *host,
755 					    unsigned int sg_len)
756 {
757 	struct dma_slave_config cfg;
758 	struct dma_async_tx_descriptor *desc = NULL;
759 	struct scatterlist *sgl = host->data->sg;
760 	const u32 mszs[] = {1, 4, 8, 16, 32, 64, 128, 256};
761 	u32 sg_elems = host->data->sg_len;
762 	u32 fifoth_val;
763 	u32 fifo_offset = host->fifo_reg - host->regs;
764 	int ret = 0;
765 
766 	/* Set external dma config: burst size, burst width */
767 	cfg.dst_addr = host->phy_regs + fifo_offset;
768 	cfg.src_addr = cfg.dst_addr;
769 	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
770 	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
771 
772 	/* Match burst msize with external dma config */
773 	fifoth_val = mci_readl(host, FIFOTH);
774 	cfg.dst_maxburst = mszs[(fifoth_val >> 28) & 0x7];
775 	cfg.src_maxburst = cfg.dst_maxburst;
776 
777 	if (host->data->flags & MMC_DATA_WRITE)
778 		cfg.direction = DMA_MEM_TO_DEV;
779 	else
780 		cfg.direction = DMA_DEV_TO_MEM;
781 
782 	ret = dmaengine_slave_config(host->dms->ch, &cfg);
783 	if (ret) {
784 		dev_err(host->dev, "Failed to config edmac.\n");
785 		return -EBUSY;
786 	}
787 
788 	desc = dmaengine_prep_slave_sg(host->dms->ch, sgl,
789 				       sg_len, cfg.direction,
790 				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
791 	if (!desc) {
792 		dev_err(host->dev, "Can't prepare slave sg.\n");
793 		return -EBUSY;
794 	}
795 
796 	/* Set dw_mci_dmac_complete_dma as callback */
797 	desc->callback = dw_mci_dmac_complete_dma;
798 	desc->callback_param = (void *)host;
799 	dmaengine_submit(desc);
800 
801 	/* Flush cache before write */
802 	if (host->data->flags & MMC_DATA_WRITE)
803 		dma_sync_sg_for_device(mmc_dev(host->cur_slot->mmc), sgl,
804 				       sg_elems, DMA_TO_DEVICE);
805 
806 	dma_async_issue_pending(host->dms->ch);
807 
808 	return 0;
809 }
810 
811 static int dw_mci_edmac_init(struct dw_mci *host)
812 {
813 	/* Request external dma channel */
814 	host->dms = kzalloc(sizeof(struct dw_mci_dma_slave), GFP_KERNEL);
815 	if (!host->dms)
816 		return -ENOMEM;
817 
818 	host->dms->ch = dma_request_slave_channel(host->dev, "rx-tx");
819 	if (!host->dms->ch) {
820 		dev_err(host->dev, "Failed to get external DMA channel.\n");
821 		kfree(host->dms);
822 		host->dms = NULL;
823 		return -ENXIO;
824 	}
825 
826 	return 0;
827 }
828 
829 static void dw_mci_edmac_exit(struct dw_mci *host)
830 {
831 	if (host->dms) {
832 		if (host->dms->ch) {
833 			dma_release_channel(host->dms->ch);
834 			host->dms->ch = NULL;
835 		}
836 		kfree(host->dms);
837 		host->dms = NULL;
838 	}
839 }
840 
841 static const struct dw_mci_dma_ops dw_mci_edmac_ops = {
842 	.init = dw_mci_edmac_init,
843 	.exit = dw_mci_edmac_exit,
844 	.start = dw_mci_edmac_start_dma,
845 	.stop = dw_mci_edmac_stop_dma,
846 	.complete = dw_mci_dmac_complete_dma,
847 	.cleanup = dw_mci_dma_cleanup,
848 };
849 
850 static int dw_mci_pre_dma_transfer(struct dw_mci *host,
851 				   struct mmc_data *data,
852 				   int cookie)
853 {
854 	struct scatterlist *sg;
855 	unsigned int i, sg_len;
856 
857 	if (data->host_cookie == COOKIE_PRE_MAPPED)
858 		return data->sg_len;
859 
860 	/*
861 	 * We don't do DMA on "complex" transfers, i.e. with
862 	 * non-word-aligned buffers or lengths. Also, we don't bother
863 	 * with all the DMA setup overhead for short transfers.
864 	 */
865 	if (data->blocks * data->blksz < DW_MCI_DMA_THRESHOLD)
866 		return -EINVAL;
867 
868 	if (data->blksz & 3)
869 		return -EINVAL;
870 
871 	for_each_sg(data->sg, sg, data->sg_len, i) {
872 		if (sg->offset & 3 || sg->length & 3)
873 			return -EINVAL;
874 	}
875 
876 	sg_len = dma_map_sg(host->dev,
877 			    data->sg,
878 			    data->sg_len,
879 			    dw_mci_get_dma_dir(data));
880 	if (sg_len == 0)
881 		return -EINVAL;
882 
883 	data->host_cookie = cookie;
884 
885 	return sg_len;
886 }
887 
888 static void dw_mci_pre_req(struct mmc_host *mmc,
889 			   struct mmc_request *mrq)
890 {
891 	struct dw_mci_slot *slot = mmc_priv(mmc);
892 	struct mmc_data *data = mrq->data;
893 
894 	if (!slot->host->use_dma || !data)
895 		return;
896 
897 	/* This data might be unmapped at this time */
898 	data->host_cookie = COOKIE_UNMAPPED;
899 
900 	if (dw_mci_pre_dma_transfer(slot->host, mrq->data,
901 				COOKIE_PRE_MAPPED) < 0)
902 		data->host_cookie = COOKIE_UNMAPPED;
903 }
904 
905 static void dw_mci_post_req(struct mmc_host *mmc,
906 			    struct mmc_request *mrq,
907 			    int err)
908 {
909 	struct dw_mci_slot *slot = mmc_priv(mmc);
910 	struct mmc_data *data = mrq->data;
911 
912 	if (!slot->host->use_dma || !data)
913 		return;
914 
915 	if (data->host_cookie != COOKIE_UNMAPPED)
916 		dma_unmap_sg(slot->host->dev,
917 			     data->sg,
918 			     data->sg_len,
919 			     dw_mci_get_dma_dir(data));
920 	data->host_cookie = COOKIE_UNMAPPED;
921 }
922 
923 static void dw_mci_adjust_fifoth(struct dw_mci *host, struct mmc_data *data)
924 {
925 	unsigned int blksz = data->blksz;
926 	const u32 mszs[] = {1, 4, 8, 16, 32, 64, 128, 256};
927 	u32 fifo_width = 1 << host->data_shift;
928 	u32 blksz_depth = blksz / fifo_width, fifoth_val;
929 	u32 msize = 0, rx_wmark = 1, tx_wmark, tx_wmark_invers;
930 	int idx = ARRAY_SIZE(mszs) - 1;
931 
932 	/* pio should ship this scenario */
933 	if (!host->use_dma)
934 		return;
935 
936 	tx_wmark = (host->fifo_depth) / 2;
937 	tx_wmark_invers = host->fifo_depth - tx_wmark;
938 
939 	/*
940 	 * MSIZE is '1',
941 	 * if blksz is not a multiple of the FIFO width
942 	 */
943 	if (blksz % fifo_width)
944 		goto done;
945 
946 	do {
947 		if (!((blksz_depth % mszs[idx]) ||
948 		     (tx_wmark_invers % mszs[idx]))) {
949 			msize = idx;
950 			rx_wmark = mszs[idx] - 1;
951 			break;
952 		}
953 	} while (--idx > 0);
954 	/*
955 	 * If idx is '0', it won't be tried
956 	 * Thus, initial values are uesed
957 	 */
958 done:
959 	fifoth_val = SDMMC_SET_FIFOTH(msize, rx_wmark, tx_wmark);
960 	mci_writel(host, FIFOTH, fifoth_val);
961 }
962 
963 static void dw_mci_ctrl_thld(struct dw_mci *host, struct mmc_data *data)
964 {
965 	unsigned int blksz = data->blksz;
966 	u32 blksz_depth, fifo_depth;
967 	u16 thld_size;
968 	u8 enable;
969 
970 	/*
971 	 * CDTHRCTL doesn't exist prior to 240A (in fact that register offset is
972 	 * in the FIFO region, so we really shouldn't access it).
973 	 */
974 	if (host->verid < DW_MMC_240A ||
975 		(host->verid < DW_MMC_280A && data->flags & MMC_DATA_WRITE))
976 		return;
977 
978 	/*
979 	 * Card write Threshold is introduced since 2.80a
980 	 * It's used when HS400 mode is enabled.
981 	 */
982 	if (data->flags & MMC_DATA_WRITE &&
983 		!(host->timing != MMC_TIMING_MMC_HS400))
984 		return;
985 
986 	if (data->flags & MMC_DATA_WRITE)
987 		enable = SDMMC_CARD_WR_THR_EN;
988 	else
989 		enable = SDMMC_CARD_RD_THR_EN;
990 
991 	if (host->timing != MMC_TIMING_MMC_HS200 &&
992 	    host->timing != MMC_TIMING_UHS_SDR104)
993 		goto disable;
994 
995 	blksz_depth = blksz / (1 << host->data_shift);
996 	fifo_depth = host->fifo_depth;
997 
998 	if (blksz_depth > fifo_depth)
999 		goto disable;
1000 
1001 	/*
1002 	 * If (blksz_depth) >= (fifo_depth >> 1), should be 'thld_size <= blksz'
1003 	 * If (blksz_depth) <  (fifo_depth >> 1), should be thld_size = blksz
1004 	 * Currently just choose blksz.
1005 	 */
1006 	thld_size = blksz;
1007 	mci_writel(host, CDTHRCTL, SDMMC_SET_THLD(thld_size, enable));
1008 	return;
1009 
1010 disable:
1011 	mci_writel(host, CDTHRCTL, 0);
1012 }
1013 
1014 static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data)
1015 {
1016 	unsigned long irqflags;
1017 	int sg_len;
1018 	u32 temp;
1019 
1020 	host->using_dma = 0;
1021 
1022 	/* If we don't have a channel, we can't do DMA */
1023 	if (!host->use_dma)
1024 		return -ENODEV;
1025 
1026 	sg_len = dw_mci_pre_dma_transfer(host, data, COOKIE_MAPPED);
1027 	if (sg_len < 0) {
1028 		host->dma_ops->stop(host);
1029 		return sg_len;
1030 	}
1031 
1032 	host->using_dma = 1;
1033 
1034 	if (host->use_dma == TRANS_MODE_IDMAC)
1035 		dev_vdbg(host->dev,
1036 			 "sd sg_cpu: %#lx sg_dma: %#lx sg_len: %d\n",
1037 			 (unsigned long)host->sg_cpu,
1038 			 (unsigned long)host->sg_dma,
1039 			 sg_len);
1040 
1041 	/*
1042 	 * Decide the MSIZE and RX/TX Watermark.
1043 	 * If current block size is same with previous size,
1044 	 * no need to update fifoth.
1045 	 */
1046 	if (host->prev_blksz != data->blksz)
1047 		dw_mci_adjust_fifoth(host, data);
1048 
1049 	/* Enable the DMA interface */
1050 	temp = mci_readl(host, CTRL);
1051 	temp |= SDMMC_CTRL_DMA_ENABLE;
1052 	mci_writel(host, CTRL, temp);
1053 
1054 	/* Disable RX/TX IRQs, let DMA handle it */
1055 	spin_lock_irqsave(&host->irq_lock, irqflags);
1056 	temp = mci_readl(host, INTMASK);
1057 	temp  &= ~(SDMMC_INT_RXDR | SDMMC_INT_TXDR);
1058 	mci_writel(host, INTMASK, temp);
1059 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
1060 
1061 	if (host->dma_ops->start(host, sg_len)) {
1062 		host->dma_ops->stop(host);
1063 		/* We can't do DMA, try PIO for this one */
1064 		dev_dbg(host->dev,
1065 			"%s: fall back to PIO mode for current transfer\n",
1066 			__func__);
1067 		return -ENODEV;
1068 	}
1069 
1070 	return 0;
1071 }
1072 
1073 static void dw_mci_submit_data(struct dw_mci *host, struct mmc_data *data)
1074 {
1075 	unsigned long irqflags;
1076 	int flags = SG_MITER_ATOMIC;
1077 	u32 temp;
1078 
1079 	data->error = -EINPROGRESS;
1080 
1081 	WARN_ON(host->data);
1082 	host->sg = NULL;
1083 	host->data = data;
1084 
1085 	if (data->flags & MMC_DATA_READ)
1086 		host->dir_status = DW_MCI_RECV_STATUS;
1087 	else
1088 		host->dir_status = DW_MCI_SEND_STATUS;
1089 
1090 	dw_mci_ctrl_thld(host, data);
1091 
1092 	if (dw_mci_submit_data_dma(host, data)) {
1093 		if (host->data->flags & MMC_DATA_READ)
1094 			flags |= SG_MITER_TO_SG;
1095 		else
1096 			flags |= SG_MITER_FROM_SG;
1097 
1098 		sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
1099 		host->sg = data->sg;
1100 		host->part_buf_start = 0;
1101 		host->part_buf_count = 0;
1102 
1103 		mci_writel(host, RINTSTS, SDMMC_INT_TXDR | SDMMC_INT_RXDR);
1104 
1105 		spin_lock_irqsave(&host->irq_lock, irqflags);
1106 		temp = mci_readl(host, INTMASK);
1107 		temp |= SDMMC_INT_TXDR | SDMMC_INT_RXDR;
1108 		mci_writel(host, INTMASK, temp);
1109 		spin_unlock_irqrestore(&host->irq_lock, irqflags);
1110 
1111 		temp = mci_readl(host, CTRL);
1112 		temp &= ~SDMMC_CTRL_DMA_ENABLE;
1113 		mci_writel(host, CTRL, temp);
1114 
1115 		/*
1116 		 * Use the initial fifoth_val for PIO mode.
1117 		 * If next issued data may be transfered by DMA mode,
1118 		 * prev_blksz should be invalidated.
1119 		 */
1120 		mci_writel(host, FIFOTH, host->fifoth_val);
1121 		host->prev_blksz = 0;
1122 	} else {
1123 		/*
1124 		 * Keep the current block size.
1125 		 * It will be used to decide whether to update
1126 		 * fifoth register next time.
1127 		 */
1128 		host->prev_blksz = data->blksz;
1129 	}
1130 }
1131 
1132 static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg)
1133 {
1134 	struct dw_mci *host = slot->host;
1135 	unsigned long timeout = jiffies + msecs_to_jiffies(500);
1136 	unsigned int cmd_status = 0;
1137 
1138 	mci_writel(host, CMDARG, arg);
1139 	wmb(); /* drain writebuffer */
1140 	dw_mci_wait_while_busy(host, cmd);
1141 	mci_writel(host, CMD, SDMMC_CMD_START | cmd);
1142 
1143 	while (time_before(jiffies, timeout)) {
1144 		cmd_status = mci_readl(host, CMD);
1145 		if (!(cmd_status & SDMMC_CMD_START))
1146 			return;
1147 	}
1148 	dev_err(&slot->mmc->class_dev,
1149 		"Timeout sending command (cmd %#x arg %#x status %#x)\n",
1150 		cmd, arg, cmd_status);
1151 }
1152 
1153 static void dw_mci_setup_bus(struct dw_mci_slot *slot, bool force_clkinit)
1154 {
1155 	struct dw_mci *host = slot->host;
1156 	unsigned int clock = slot->clock;
1157 	u32 div;
1158 	u32 clk_en_a;
1159 	u32 sdmmc_cmd_bits = SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT;
1160 
1161 	/* We must continue to set bit 28 in CMD until the change is complete */
1162 	if (host->state == STATE_WAITING_CMD11_DONE)
1163 		sdmmc_cmd_bits |= SDMMC_CMD_VOLT_SWITCH;
1164 
1165 	if (!clock) {
1166 		mci_writel(host, CLKENA, 0);
1167 		mci_send_cmd(slot, sdmmc_cmd_bits, 0);
1168 	} else if (clock != host->current_speed || force_clkinit) {
1169 		div = host->bus_hz / clock;
1170 		if (host->bus_hz % clock && host->bus_hz > clock)
1171 			/*
1172 			 * move the + 1 after the divide to prevent
1173 			 * over-clocking the card.
1174 			 */
1175 			div += 1;
1176 
1177 		div = (host->bus_hz != clock) ? DIV_ROUND_UP(div, 2) : 0;
1178 
1179 		if ((clock != slot->__clk_old &&
1180 			!test_bit(DW_MMC_CARD_NEEDS_POLL, &slot->flags)) ||
1181 			force_clkinit) {
1182 			dev_info(&slot->mmc->class_dev,
1183 				 "Bus speed (slot %d) = %dHz (slot req %dHz, actual %dHZ div = %d)\n",
1184 				 slot->id, host->bus_hz, clock,
1185 				 div ? ((host->bus_hz / div) >> 1) :
1186 				 host->bus_hz, div);
1187 
1188 			/*
1189 			 * If card is polling, display the message only
1190 			 * one time at boot time.
1191 			 */
1192 			if (slot->mmc->caps & MMC_CAP_NEEDS_POLL &&
1193 					slot->mmc->f_min == clock)
1194 				set_bit(DW_MMC_CARD_NEEDS_POLL, &slot->flags);
1195 		}
1196 
1197 		/* disable clock */
1198 		mci_writel(host, CLKENA, 0);
1199 		mci_writel(host, CLKSRC, 0);
1200 
1201 		/* inform CIU */
1202 		mci_send_cmd(slot, sdmmc_cmd_bits, 0);
1203 
1204 		/* set clock to desired speed */
1205 		mci_writel(host, CLKDIV, div);
1206 
1207 		/* inform CIU */
1208 		mci_send_cmd(slot, sdmmc_cmd_bits, 0);
1209 
1210 		/* enable clock; only low power if no SDIO */
1211 		clk_en_a = SDMMC_CLKEN_ENABLE << slot->id;
1212 		if (!test_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags))
1213 			clk_en_a |= SDMMC_CLKEN_LOW_PWR << slot->id;
1214 		mci_writel(host, CLKENA, clk_en_a);
1215 
1216 		/* inform CIU */
1217 		mci_send_cmd(slot, sdmmc_cmd_bits, 0);
1218 
1219 		/* keep the last clock value that was requested from core */
1220 		slot->__clk_old = clock;
1221 	}
1222 
1223 	host->current_speed = clock;
1224 
1225 	/* Set the current slot bus width */
1226 	mci_writel(host, CTYPE, (slot->ctype << slot->id));
1227 }
1228 
1229 static void __dw_mci_start_request(struct dw_mci *host,
1230 				   struct dw_mci_slot *slot,
1231 				   struct mmc_command *cmd)
1232 {
1233 	struct mmc_request *mrq;
1234 	struct mmc_data	*data;
1235 	u32 cmdflags;
1236 
1237 	mrq = slot->mrq;
1238 
1239 	host->cur_slot = slot;
1240 	host->mrq = mrq;
1241 
1242 	host->pending_events = 0;
1243 	host->completed_events = 0;
1244 	host->cmd_status = 0;
1245 	host->data_status = 0;
1246 	host->dir_status = 0;
1247 
1248 	data = cmd->data;
1249 	if (data) {
1250 		mci_writel(host, TMOUT, 0xFFFFFFFF);
1251 		mci_writel(host, BYTCNT, data->blksz*data->blocks);
1252 		mci_writel(host, BLKSIZ, data->blksz);
1253 	}
1254 
1255 	cmdflags = dw_mci_prepare_command(slot->mmc, cmd);
1256 
1257 	/* this is the first command, send the initialization clock */
1258 	if (test_and_clear_bit(DW_MMC_CARD_NEED_INIT, &slot->flags))
1259 		cmdflags |= SDMMC_CMD_INIT;
1260 
1261 	if (data) {
1262 		dw_mci_submit_data(host, data);
1263 		wmb(); /* drain writebuffer */
1264 	}
1265 
1266 	dw_mci_start_command(host, cmd, cmdflags);
1267 
1268 	if (cmd->opcode == SD_SWITCH_VOLTAGE) {
1269 		unsigned long irqflags;
1270 
1271 		/*
1272 		 * Databook says to fail after 2ms w/ no response, but evidence
1273 		 * shows that sometimes the cmd11 interrupt takes over 130ms.
1274 		 * We'll set to 500ms, plus an extra jiffy just in case jiffies
1275 		 * is just about to roll over.
1276 		 *
1277 		 * We do this whole thing under spinlock and only if the
1278 		 * command hasn't already completed (indicating the the irq
1279 		 * already ran so we don't want the timeout).
1280 		 */
1281 		spin_lock_irqsave(&host->irq_lock, irqflags);
1282 		if (!test_bit(EVENT_CMD_COMPLETE, &host->pending_events))
1283 			mod_timer(&host->cmd11_timer,
1284 				jiffies + msecs_to_jiffies(500) + 1);
1285 		spin_unlock_irqrestore(&host->irq_lock, irqflags);
1286 	}
1287 
1288 	host->stop_cmdr = dw_mci_prep_stop_abort(host, cmd);
1289 }
1290 
1291 static void dw_mci_start_request(struct dw_mci *host,
1292 				 struct dw_mci_slot *slot)
1293 {
1294 	struct mmc_request *mrq = slot->mrq;
1295 	struct mmc_command *cmd;
1296 
1297 	cmd = mrq->sbc ? mrq->sbc : mrq->cmd;
1298 	__dw_mci_start_request(host, slot, cmd);
1299 }
1300 
1301 /* must be called with host->lock held */
1302 static void dw_mci_queue_request(struct dw_mci *host, struct dw_mci_slot *slot,
1303 				 struct mmc_request *mrq)
1304 {
1305 	dev_vdbg(&slot->mmc->class_dev, "queue request: state=%d\n",
1306 		 host->state);
1307 
1308 	slot->mrq = mrq;
1309 
1310 	if (host->state == STATE_WAITING_CMD11_DONE) {
1311 		dev_warn(&slot->mmc->class_dev,
1312 			 "Voltage change didn't complete\n");
1313 		/*
1314 		 * this case isn't expected to happen, so we can
1315 		 * either crash here or just try to continue on
1316 		 * in the closest possible state
1317 		 */
1318 		host->state = STATE_IDLE;
1319 	}
1320 
1321 	if (host->state == STATE_IDLE) {
1322 		host->state = STATE_SENDING_CMD;
1323 		dw_mci_start_request(host, slot);
1324 	} else {
1325 		list_add_tail(&slot->queue_node, &host->queue);
1326 	}
1327 }
1328 
1329 static void dw_mci_request(struct mmc_host *mmc, struct mmc_request *mrq)
1330 {
1331 	struct dw_mci_slot *slot = mmc_priv(mmc);
1332 	struct dw_mci *host = slot->host;
1333 
1334 	WARN_ON(slot->mrq);
1335 
1336 	/*
1337 	 * The check for card presence and queueing of the request must be
1338 	 * atomic, otherwise the card could be removed in between and the
1339 	 * request wouldn't fail until another card was inserted.
1340 	 */
1341 
1342 	if (!dw_mci_get_cd(mmc)) {
1343 		mrq->cmd->error = -ENOMEDIUM;
1344 		mmc_request_done(mmc, mrq);
1345 		return;
1346 	}
1347 
1348 	spin_lock_bh(&host->lock);
1349 
1350 	dw_mci_queue_request(host, slot, mrq);
1351 
1352 	spin_unlock_bh(&host->lock);
1353 }
1354 
1355 static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1356 {
1357 	struct dw_mci_slot *slot = mmc_priv(mmc);
1358 	const struct dw_mci_drv_data *drv_data = slot->host->drv_data;
1359 	u32 regs;
1360 	int ret;
1361 
1362 	switch (ios->bus_width) {
1363 	case MMC_BUS_WIDTH_4:
1364 		slot->ctype = SDMMC_CTYPE_4BIT;
1365 		break;
1366 	case MMC_BUS_WIDTH_8:
1367 		slot->ctype = SDMMC_CTYPE_8BIT;
1368 		break;
1369 	default:
1370 		/* set default 1 bit mode */
1371 		slot->ctype = SDMMC_CTYPE_1BIT;
1372 	}
1373 
1374 	regs = mci_readl(slot->host, UHS_REG);
1375 
1376 	/* DDR mode set */
1377 	if (ios->timing == MMC_TIMING_MMC_DDR52 ||
1378 	    ios->timing == MMC_TIMING_UHS_DDR50 ||
1379 	    ios->timing == MMC_TIMING_MMC_HS400)
1380 		regs |= ((0x1 << slot->id) << 16);
1381 	else
1382 		regs &= ~((0x1 << slot->id) << 16);
1383 
1384 	mci_writel(slot->host, UHS_REG, regs);
1385 	slot->host->timing = ios->timing;
1386 
1387 	/*
1388 	 * Use mirror of ios->clock to prevent race with mmc
1389 	 * core ios update when finding the minimum.
1390 	 */
1391 	slot->clock = ios->clock;
1392 
1393 	if (drv_data && drv_data->set_ios)
1394 		drv_data->set_ios(slot->host, ios);
1395 
1396 	switch (ios->power_mode) {
1397 	case MMC_POWER_UP:
1398 		if (!IS_ERR(mmc->supply.vmmc)) {
1399 			ret = mmc_regulator_set_ocr(mmc, mmc->supply.vmmc,
1400 					ios->vdd);
1401 			if (ret) {
1402 				dev_err(slot->host->dev,
1403 					"failed to enable vmmc regulator\n");
1404 				/*return, if failed turn on vmmc*/
1405 				return;
1406 			}
1407 		}
1408 		set_bit(DW_MMC_CARD_NEED_INIT, &slot->flags);
1409 		regs = mci_readl(slot->host, PWREN);
1410 		regs |= (1 << slot->id);
1411 		mci_writel(slot->host, PWREN, regs);
1412 		break;
1413 	case MMC_POWER_ON:
1414 		if (!slot->host->vqmmc_enabled) {
1415 			if (!IS_ERR(mmc->supply.vqmmc)) {
1416 				ret = regulator_enable(mmc->supply.vqmmc);
1417 				if (ret < 0)
1418 					dev_err(slot->host->dev,
1419 						"failed to enable vqmmc\n");
1420 				else
1421 					slot->host->vqmmc_enabled = true;
1422 
1423 			} else {
1424 				/* Keep track so we don't reset again */
1425 				slot->host->vqmmc_enabled = true;
1426 			}
1427 
1428 			/* Reset our state machine after powering on */
1429 			dw_mci_ctrl_reset(slot->host,
1430 					  SDMMC_CTRL_ALL_RESET_FLAGS);
1431 		}
1432 
1433 		/* Adjust clock / bus width after power is up */
1434 		dw_mci_setup_bus(slot, false);
1435 
1436 		break;
1437 	case MMC_POWER_OFF:
1438 		/* Turn clock off before power goes down */
1439 		dw_mci_setup_bus(slot, false);
1440 
1441 		if (!IS_ERR(mmc->supply.vmmc))
1442 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
1443 
1444 		if (!IS_ERR(mmc->supply.vqmmc) && slot->host->vqmmc_enabled)
1445 			regulator_disable(mmc->supply.vqmmc);
1446 		slot->host->vqmmc_enabled = false;
1447 
1448 		regs = mci_readl(slot->host, PWREN);
1449 		regs &= ~(1 << slot->id);
1450 		mci_writel(slot->host, PWREN, regs);
1451 		break;
1452 	default:
1453 		break;
1454 	}
1455 
1456 	if (slot->host->state == STATE_WAITING_CMD11_DONE && ios->clock != 0)
1457 		slot->host->state = STATE_IDLE;
1458 }
1459 
1460 static int dw_mci_card_busy(struct mmc_host *mmc)
1461 {
1462 	struct dw_mci_slot *slot = mmc_priv(mmc);
1463 	u32 status;
1464 
1465 	/*
1466 	 * Check the busy bit which is low when DAT[3:0]
1467 	 * (the data lines) are 0000
1468 	 */
1469 	status = mci_readl(slot->host, STATUS);
1470 
1471 	return !!(status & SDMMC_STATUS_BUSY);
1472 }
1473 
1474 static int dw_mci_switch_voltage(struct mmc_host *mmc, struct mmc_ios *ios)
1475 {
1476 	struct dw_mci_slot *slot = mmc_priv(mmc);
1477 	struct dw_mci *host = slot->host;
1478 	const struct dw_mci_drv_data *drv_data = host->drv_data;
1479 	u32 uhs;
1480 	u32 v18 = SDMMC_UHS_18V << slot->id;
1481 	int ret;
1482 
1483 	if (drv_data && drv_data->switch_voltage)
1484 		return drv_data->switch_voltage(mmc, ios);
1485 
1486 	/*
1487 	 * Program the voltage.  Note that some instances of dw_mmc may use
1488 	 * the UHS_REG for this.  For other instances (like exynos) the UHS_REG
1489 	 * does no harm but you need to set the regulator directly.  Try both.
1490 	 */
1491 	uhs = mci_readl(host, UHS_REG);
1492 	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
1493 		uhs &= ~v18;
1494 	else
1495 		uhs |= v18;
1496 
1497 	if (!IS_ERR(mmc->supply.vqmmc)) {
1498 		ret = mmc_regulator_set_vqmmc(mmc, ios);
1499 
1500 		if (ret) {
1501 			dev_dbg(&mmc->class_dev,
1502 					 "Regulator set error %d - %s V\n",
1503 					 ret, uhs & v18 ? "1.8" : "3.3");
1504 			return ret;
1505 		}
1506 	}
1507 	mci_writel(host, UHS_REG, uhs);
1508 
1509 	return 0;
1510 }
1511 
1512 static int dw_mci_get_ro(struct mmc_host *mmc)
1513 {
1514 	int read_only;
1515 	struct dw_mci_slot *slot = mmc_priv(mmc);
1516 	int gpio_ro = mmc_gpio_get_ro(mmc);
1517 
1518 	/* Use platform get_ro function, else try on board write protect */
1519 	if (gpio_ro >= 0)
1520 		read_only = gpio_ro;
1521 	else
1522 		read_only =
1523 			mci_readl(slot->host, WRTPRT) & (1 << slot->id) ? 1 : 0;
1524 
1525 	dev_dbg(&mmc->class_dev, "card is %s\n",
1526 		read_only ? "read-only" : "read-write");
1527 
1528 	return read_only;
1529 }
1530 
1531 static int dw_mci_get_cd(struct mmc_host *mmc)
1532 {
1533 	int present;
1534 	struct dw_mci_slot *slot = mmc_priv(mmc);
1535 	struct dw_mci *host = slot->host;
1536 	int gpio_cd = mmc_gpio_get_cd(mmc);
1537 
1538 	/* Use platform get_cd function, else try onboard card detect */
1539 	if (((mmc->caps & MMC_CAP_NEEDS_POLL)
1540 				|| !mmc_card_is_removable(mmc))) {
1541 		present = 1;
1542 
1543 		if (!test_bit(DW_MMC_CARD_PRESENT, &slot->flags)) {
1544 			if (mmc->caps & MMC_CAP_NEEDS_POLL) {
1545 				dev_info(&mmc->class_dev,
1546 					"card is polling.\n");
1547 			} else {
1548 				dev_info(&mmc->class_dev,
1549 					"card is non-removable.\n");
1550 			}
1551 			set_bit(DW_MMC_CARD_PRESENT, &slot->flags);
1552 		}
1553 
1554 		return present;
1555 	} else if (gpio_cd >= 0)
1556 		present = gpio_cd;
1557 	else
1558 		present = (mci_readl(slot->host, CDETECT) & (1 << slot->id))
1559 			== 0 ? 1 : 0;
1560 
1561 	spin_lock_bh(&host->lock);
1562 	if (present && !test_and_set_bit(DW_MMC_CARD_PRESENT, &slot->flags))
1563 		dev_dbg(&mmc->class_dev, "card is present\n");
1564 	else if (!present &&
1565 			!test_and_clear_bit(DW_MMC_CARD_PRESENT, &slot->flags))
1566 		dev_dbg(&mmc->class_dev, "card is not present\n");
1567 	spin_unlock_bh(&host->lock);
1568 
1569 	return present;
1570 }
1571 
1572 static void dw_mci_hw_reset(struct mmc_host *mmc)
1573 {
1574 	struct dw_mci_slot *slot = mmc_priv(mmc);
1575 	struct dw_mci *host = slot->host;
1576 	int reset;
1577 
1578 	if (host->use_dma == TRANS_MODE_IDMAC)
1579 		dw_mci_idmac_reset(host);
1580 
1581 	if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_DMA_RESET |
1582 				     SDMMC_CTRL_FIFO_RESET))
1583 		return;
1584 
1585 	/*
1586 	 * According to eMMC spec, card reset procedure:
1587 	 * tRstW >= 1us:   RST_n pulse width
1588 	 * tRSCA >= 200us: RST_n to Command time
1589 	 * tRSTH >= 1us:   RST_n high period
1590 	 */
1591 	reset = mci_readl(host, RST_N);
1592 	reset &= ~(SDMMC_RST_HWACTIVE << slot->id);
1593 	mci_writel(host, RST_N, reset);
1594 	usleep_range(1, 2);
1595 	reset |= SDMMC_RST_HWACTIVE << slot->id;
1596 	mci_writel(host, RST_N, reset);
1597 	usleep_range(200, 300);
1598 }
1599 
1600 static void dw_mci_init_card(struct mmc_host *mmc, struct mmc_card *card)
1601 {
1602 	struct dw_mci_slot *slot = mmc_priv(mmc);
1603 	struct dw_mci *host = slot->host;
1604 
1605 	/*
1606 	 * Low power mode will stop the card clock when idle.  According to the
1607 	 * description of the CLKENA register we should disable low power mode
1608 	 * for SDIO cards if we need SDIO interrupts to work.
1609 	 */
1610 	if (mmc->caps & MMC_CAP_SDIO_IRQ) {
1611 		const u32 clken_low_pwr = SDMMC_CLKEN_LOW_PWR << slot->id;
1612 		u32 clk_en_a_old;
1613 		u32 clk_en_a;
1614 
1615 		clk_en_a_old = mci_readl(host, CLKENA);
1616 
1617 		if (card->type == MMC_TYPE_SDIO ||
1618 		    card->type == MMC_TYPE_SD_COMBO) {
1619 			set_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags);
1620 			clk_en_a = clk_en_a_old & ~clken_low_pwr;
1621 		} else {
1622 			clear_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags);
1623 			clk_en_a = clk_en_a_old | clken_low_pwr;
1624 		}
1625 
1626 		if (clk_en_a != clk_en_a_old) {
1627 			mci_writel(host, CLKENA, clk_en_a);
1628 			mci_send_cmd(slot, SDMMC_CMD_UPD_CLK |
1629 				     SDMMC_CMD_PRV_DAT_WAIT, 0);
1630 		}
1631 	}
1632 }
1633 
1634 static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb)
1635 {
1636 	struct dw_mci_slot *slot = mmc_priv(mmc);
1637 	struct dw_mci *host = slot->host;
1638 	unsigned long irqflags;
1639 	u32 int_mask;
1640 
1641 	spin_lock_irqsave(&host->irq_lock, irqflags);
1642 
1643 	/* Enable/disable Slot Specific SDIO interrupt */
1644 	int_mask = mci_readl(host, INTMASK);
1645 	if (enb)
1646 		int_mask |= SDMMC_INT_SDIO(slot->sdio_id);
1647 	else
1648 		int_mask &= ~SDMMC_INT_SDIO(slot->sdio_id);
1649 	mci_writel(host, INTMASK, int_mask);
1650 
1651 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
1652 }
1653 
1654 static int dw_mci_execute_tuning(struct mmc_host *mmc, u32 opcode)
1655 {
1656 	struct dw_mci_slot *slot = mmc_priv(mmc);
1657 	struct dw_mci *host = slot->host;
1658 	const struct dw_mci_drv_data *drv_data = host->drv_data;
1659 	int err = -EINVAL;
1660 
1661 	if (drv_data && drv_data->execute_tuning)
1662 		err = drv_data->execute_tuning(slot, opcode);
1663 	return err;
1664 }
1665 
1666 static int dw_mci_prepare_hs400_tuning(struct mmc_host *mmc,
1667 				       struct mmc_ios *ios)
1668 {
1669 	struct dw_mci_slot *slot = mmc_priv(mmc);
1670 	struct dw_mci *host = slot->host;
1671 	const struct dw_mci_drv_data *drv_data = host->drv_data;
1672 
1673 	if (drv_data && drv_data->prepare_hs400_tuning)
1674 		return drv_data->prepare_hs400_tuning(host, ios);
1675 
1676 	return 0;
1677 }
1678 
1679 static const struct mmc_host_ops dw_mci_ops = {
1680 	.request		= dw_mci_request,
1681 	.pre_req		= dw_mci_pre_req,
1682 	.post_req		= dw_mci_post_req,
1683 	.set_ios		= dw_mci_set_ios,
1684 	.get_ro			= dw_mci_get_ro,
1685 	.get_cd			= dw_mci_get_cd,
1686 	.hw_reset               = dw_mci_hw_reset,
1687 	.enable_sdio_irq	= dw_mci_enable_sdio_irq,
1688 	.execute_tuning		= dw_mci_execute_tuning,
1689 	.card_busy		= dw_mci_card_busy,
1690 	.start_signal_voltage_switch = dw_mci_switch_voltage,
1691 	.init_card		= dw_mci_init_card,
1692 	.prepare_hs400_tuning	= dw_mci_prepare_hs400_tuning,
1693 };
1694 
1695 static void dw_mci_request_end(struct dw_mci *host, struct mmc_request *mrq)
1696 	__releases(&host->lock)
1697 	__acquires(&host->lock)
1698 {
1699 	struct dw_mci_slot *slot;
1700 	struct mmc_host	*prev_mmc = host->cur_slot->mmc;
1701 
1702 	WARN_ON(host->cmd || host->data);
1703 
1704 	host->cur_slot->mrq = NULL;
1705 	host->mrq = NULL;
1706 	if (!list_empty(&host->queue)) {
1707 		slot = list_entry(host->queue.next,
1708 				  struct dw_mci_slot, queue_node);
1709 		list_del(&slot->queue_node);
1710 		dev_vdbg(host->dev, "list not empty: %s is next\n",
1711 			 mmc_hostname(slot->mmc));
1712 		host->state = STATE_SENDING_CMD;
1713 		dw_mci_start_request(host, slot);
1714 	} else {
1715 		dev_vdbg(host->dev, "list empty\n");
1716 
1717 		if (host->state == STATE_SENDING_CMD11)
1718 			host->state = STATE_WAITING_CMD11_DONE;
1719 		else
1720 			host->state = STATE_IDLE;
1721 	}
1722 
1723 	spin_unlock(&host->lock);
1724 	mmc_request_done(prev_mmc, mrq);
1725 	spin_lock(&host->lock);
1726 }
1727 
1728 static int dw_mci_command_complete(struct dw_mci *host, struct mmc_command *cmd)
1729 {
1730 	u32 status = host->cmd_status;
1731 
1732 	host->cmd_status = 0;
1733 
1734 	/* Read the response from the card (up to 16 bytes) */
1735 	if (cmd->flags & MMC_RSP_PRESENT) {
1736 		if (cmd->flags & MMC_RSP_136) {
1737 			cmd->resp[3] = mci_readl(host, RESP0);
1738 			cmd->resp[2] = mci_readl(host, RESP1);
1739 			cmd->resp[1] = mci_readl(host, RESP2);
1740 			cmd->resp[0] = mci_readl(host, RESP3);
1741 		} else {
1742 			cmd->resp[0] = mci_readl(host, RESP0);
1743 			cmd->resp[1] = 0;
1744 			cmd->resp[2] = 0;
1745 			cmd->resp[3] = 0;
1746 		}
1747 	}
1748 
1749 	if (status & SDMMC_INT_RTO)
1750 		cmd->error = -ETIMEDOUT;
1751 	else if ((cmd->flags & MMC_RSP_CRC) && (status & SDMMC_INT_RCRC))
1752 		cmd->error = -EILSEQ;
1753 	else if (status & SDMMC_INT_RESP_ERR)
1754 		cmd->error = -EIO;
1755 	else
1756 		cmd->error = 0;
1757 
1758 	return cmd->error;
1759 }
1760 
1761 static int dw_mci_data_complete(struct dw_mci *host, struct mmc_data *data)
1762 {
1763 	u32 status = host->data_status;
1764 
1765 	if (status & DW_MCI_DATA_ERROR_FLAGS) {
1766 		if (status & SDMMC_INT_DRTO) {
1767 			data->error = -ETIMEDOUT;
1768 		} else if (status & SDMMC_INT_DCRC) {
1769 			data->error = -EILSEQ;
1770 		} else if (status & SDMMC_INT_EBE) {
1771 			if (host->dir_status ==
1772 				DW_MCI_SEND_STATUS) {
1773 				/*
1774 				 * No data CRC status was returned.
1775 				 * The number of bytes transferred
1776 				 * will be exaggerated in PIO mode.
1777 				 */
1778 				data->bytes_xfered = 0;
1779 				data->error = -ETIMEDOUT;
1780 			} else if (host->dir_status ==
1781 					DW_MCI_RECV_STATUS) {
1782 				data->error = -EILSEQ;
1783 			}
1784 		} else {
1785 			/* SDMMC_INT_SBE is included */
1786 			data->error = -EILSEQ;
1787 		}
1788 
1789 		dev_dbg(host->dev, "data error, status 0x%08x\n", status);
1790 
1791 		/*
1792 		 * After an error, there may be data lingering
1793 		 * in the FIFO
1794 		 */
1795 		dw_mci_reset(host);
1796 	} else {
1797 		data->bytes_xfered = data->blocks * data->blksz;
1798 		data->error = 0;
1799 	}
1800 
1801 	return data->error;
1802 }
1803 
1804 static void dw_mci_set_drto(struct dw_mci *host)
1805 {
1806 	unsigned int drto_clks;
1807 	unsigned int drto_ms;
1808 
1809 	drto_clks = mci_readl(host, TMOUT) >> 8;
1810 	drto_ms = DIV_ROUND_UP(drto_clks, host->bus_hz / 1000);
1811 
1812 	/* add a bit spare time */
1813 	drto_ms += 10;
1814 
1815 	mod_timer(&host->dto_timer, jiffies + msecs_to_jiffies(drto_ms));
1816 }
1817 
1818 static void dw_mci_tasklet_func(unsigned long priv)
1819 {
1820 	struct dw_mci *host = (struct dw_mci *)priv;
1821 	struct mmc_data	*data;
1822 	struct mmc_command *cmd;
1823 	struct mmc_request *mrq;
1824 	enum dw_mci_state state;
1825 	enum dw_mci_state prev_state;
1826 	unsigned int err;
1827 
1828 	spin_lock(&host->lock);
1829 
1830 	state = host->state;
1831 	data = host->data;
1832 	mrq = host->mrq;
1833 
1834 	do {
1835 		prev_state = state;
1836 
1837 		switch (state) {
1838 		case STATE_IDLE:
1839 		case STATE_WAITING_CMD11_DONE:
1840 			break;
1841 
1842 		case STATE_SENDING_CMD11:
1843 		case STATE_SENDING_CMD:
1844 			if (!test_and_clear_bit(EVENT_CMD_COMPLETE,
1845 						&host->pending_events))
1846 				break;
1847 
1848 			cmd = host->cmd;
1849 			host->cmd = NULL;
1850 			set_bit(EVENT_CMD_COMPLETE, &host->completed_events);
1851 			err = dw_mci_command_complete(host, cmd);
1852 			if (cmd == mrq->sbc && !err) {
1853 				prev_state = state = STATE_SENDING_CMD;
1854 				__dw_mci_start_request(host, host->cur_slot,
1855 						       mrq->cmd);
1856 				goto unlock;
1857 			}
1858 
1859 			if (cmd->data && err) {
1860 				/*
1861 				 * During UHS tuning sequence, sending the stop
1862 				 * command after the response CRC error would
1863 				 * throw the system into a confused state
1864 				 * causing all future tuning phases to report
1865 				 * failure.
1866 				 *
1867 				 * In such case controller will move into a data
1868 				 * transfer state after a response error or
1869 				 * response CRC error. Let's let that finish
1870 				 * before trying to send a stop, so we'll go to
1871 				 * STATE_SENDING_DATA.
1872 				 *
1873 				 * Although letting the data transfer take place
1874 				 * will waste a bit of time (we already know
1875 				 * the command was bad), it can't cause any
1876 				 * errors since it's possible it would have
1877 				 * taken place anyway if this tasklet got
1878 				 * delayed. Allowing the transfer to take place
1879 				 * avoids races and keeps things simple.
1880 				 */
1881 				if ((err != -ETIMEDOUT) &&
1882 				    (cmd->opcode == MMC_SEND_TUNING_BLOCK)) {
1883 					state = STATE_SENDING_DATA;
1884 					continue;
1885 				}
1886 
1887 				dw_mci_stop_dma(host);
1888 				send_stop_abort(host, data);
1889 				state = STATE_SENDING_STOP;
1890 				break;
1891 			}
1892 
1893 			if (!cmd->data || err) {
1894 				dw_mci_request_end(host, mrq);
1895 				goto unlock;
1896 			}
1897 
1898 			prev_state = state = STATE_SENDING_DATA;
1899 			/* fall through */
1900 
1901 		case STATE_SENDING_DATA:
1902 			/*
1903 			 * We could get a data error and never a transfer
1904 			 * complete so we'd better check for it here.
1905 			 *
1906 			 * Note that we don't really care if we also got a
1907 			 * transfer complete; stopping the DMA and sending an
1908 			 * abort won't hurt.
1909 			 */
1910 			if (test_and_clear_bit(EVENT_DATA_ERROR,
1911 					       &host->pending_events)) {
1912 				dw_mci_stop_dma(host);
1913 				if (!(host->data_status & (SDMMC_INT_DRTO |
1914 							   SDMMC_INT_EBE)))
1915 					send_stop_abort(host, data);
1916 				state = STATE_DATA_ERROR;
1917 				break;
1918 			}
1919 
1920 			if (!test_and_clear_bit(EVENT_XFER_COMPLETE,
1921 						&host->pending_events)) {
1922 				/*
1923 				 * If all data-related interrupts don't come
1924 				 * within the given time in reading data state.
1925 				 */
1926 				if (host->dir_status == DW_MCI_RECV_STATUS)
1927 					dw_mci_set_drto(host);
1928 				break;
1929 			}
1930 
1931 			set_bit(EVENT_XFER_COMPLETE, &host->completed_events);
1932 
1933 			/*
1934 			 * Handle an EVENT_DATA_ERROR that might have shown up
1935 			 * before the transfer completed.  This might not have
1936 			 * been caught by the check above because the interrupt
1937 			 * could have gone off between the previous check and
1938 			 * the check for transfer complete.
1939 			 *
1940 			 * Technically this ought not be needed assuming we
1941 			 * get a DATA_COMPLETE eventually (we'll notice the
1942 			 * error and end the request), but it shouldn't hurt.
1943 			 *
1944 			 * This has the advantage of sending the stop command.
1945 			 */
1946 			if (test_and_clear_bit(EVENT_DATA_ERROR,
1947 					       &host->pending_events)) {
1948 				dw_mci_stop_dma(host);
1949 				if (!(host->data_status & (SDMMC_INT_DRTO |
1950 							   SDMMC_INT_EBE)))
1951 					send_stop_abort(host, data);
1952 				state = STATE_DATA_ERROR;
1953 				break;
1954 			}
1955 			prev_state = state = STATE_DATA_BUSY;
1956 
1957 			/* fall through */
1958 
1959 		case STATE_DATA_BUSY:
1960 			if (!test_and_clear_bit(EVENT_DATA_COMPLETE,
1961 						&host->pending_events)) {
1962 				/*
1963 				 * If data error interrupt comes but data over
1964 				 * interrupt doesn't come within the given time.
1965 				 * in reading data state.
1966 				 */
1967 				if (host->dir_status == DW_MCI_RECV_STATUS)
1968 					dw_mci_set_drto(host);
1969 				break;
1970 			}
1971 
1972 			host->data = NULL;
1973 			set_bit(EVENT_DATA_COMPLETE, &host->completed_events);
1974 			err = dw_mci_data_complete(host, data);
1975 
1976 			if (!err) {
1977 				if (!data->stop || mrq->sbc) {
1978 					if (mrq->sbc && data->stop)
1979 						data->stop->error = 0;
1980 					dw_mci_request_end(host, mrq);
1981 					goto unlock;
1982 				}
1983 
1984 				/* stop command for open-ended transfer*/
1985 				if (data->stop)
1986 					send_stop_abort(host, data);
1987 			} else {
1988 				/*
1989 				 * If we don't have a command complete now we'll
1990 				 * never get one since we just reset everything;
1991 				 * better end the request.
1992 				 *
1993 				 * If we do have a command complete we'll fall
1994 				 * through to the SENDING_STOP command and
1995 				 * everything will be peachy keen.
1996 				 */
1997 				if (!test_bit(EVENT_CMD_COMPLETE,
1998 					      &host->pending_events)) {
1999 					host->cmd = NULL;
2000 					dw_mci_request_end(host, mrq);
2001 					goto unlock;
2002 				}
2003 			}
2004 
2005 			/*
2006 			 * If err has non-zero,
2007 			 * stop-abort command has been already issued.
2008 			 */
2009 			prev_state = state = STATE_SENDING_STOP;
2010 
2011 			/* fall through */
2012 
2013 		case STATE_SENDING_STOP:
2014 			if (!test_and_clear_bit(EVENT_CMD_COMPLETE,
2015 						&host->pending_events))
2016 				break;
2017 
2018 			/* CMD error in data command */
2019 			if (mrq->cmd->error && mrq->data)
2020 				dw_mci_reset(host);
2021 
2022 			host->cmd = NULL;
2023 			host->data = NULL;
2024 
2025 			if (!mrq->sbc && mrq->stop)
2026 				dw_mci_command_complete(host, mrq->stop);
2027 			else
2028 				host->cmd_status = 0;
2029 
2030 			dw_mci_request_end(host, mrq);
2031 			goto unlock;
2032 
2033 		case STATE_DATA_ERROR:
2034 			if (!test_and_clear_bit(EVENT_XFER_COMPLETE,
2035 						&host->pending_events))
2036 				break;
2037 
2038 			state = STATE_DATA_BUSY;
2039 			break;
2040 		}
2041 	} while (state != prev_state);
2042 
2043 	host->state = state;
2044 unlock:
2045 	spin_unlock(&host->lock);
2046 
2047 }
2048 
2049 /* push final bytes to part_buf, only use during push */
2050 static void dw_mci_set_part_bytes(struct dw_mci *host, void *buf, int cnt)
2051 {
2052 	memcpy((void *)&host->part_buf, buf, cnt);
2053 	host->part_buf_count = cnt;
2054 }
2055 
2056 /* append bytes to part_buf, only use during push */
2057 static int dw_mci_push_part_bytes(struct dw_mci *host, void *buf, int cnt)
2058 {
2059 	cnt = min(cnt, (1 << host->data_shift) - host->part_buf_count);
2060 	memcpy((void *)&host->part_buf + host->part_buf_count, buf, cnt);
2061 	host->part_buf_count += cnt;
2062 	return cnt;
2063 }
2064 
2065 /* pull first bytes from part_buf, only use during pull */
2066 static int dw_mci_pull_part_bytes(struct dw_mci *host, void *buf, int cnt)
2067 {
2068 	cnt = min_t(int, cnt, host->part_buf_count);
2069 	if (cnt) {
2070 		memcpy(buf, (void *)&host->part_buf + host->part_buf_start,
2071 		       cnt);
2072 		host->part_buf_count -= cnt;
2073 		host->part_buf_start += cnt;
2074 	}
2075 	return cnt;
2076 }
2077 
2078 /* pull final bytes from the part_buf, assuming it's just been filled */
2079 static void dw_mci_pull_final_bytes(struct dw_mci *host, void *buf, int cnt)
2080 {
2081 	memcpy(buf, &host->part_buf, cnt);
2082 	host->part_buf_start = cnt;
2083 	host->part_buf_count = (1 << host->data_shift) - cnt;
2084 }
2085 
2086 static void dw_mci_push_data16(struct dw_mci *host, void *buf, int cnt)
2087 {
2088 	struct mmc_data *data = host->data;
2089 	int init_cnt = cnt;
2090 
2091 	/* try and push anything in the part_buf */
2092 	if (unlikely(host->part_buf_count)) {
2093 		int len = dw_mci_push_part_bytes(host, buf, cnt);
2094 
2095 		buf += len;
2096 		cnt -= len;
2097 		if (host->part_buf_count == 2) {
2098 			mci_fifo_writew(host->fifo_reg, host->part_buf16);
2099 			host->part_buf_count = 0;
2100 		}
2101 	}
2102 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2103 	if (unlikely((unsigned long)buf & 0x1)) {
2104 		while (cnt >= 2) {
2105 			u16 aligned_buf[64];
2106 			int len = min(cnt & -2, (int)sizeof(aligned_buf));
2107 			int items = len >> 1;
2108 			int i;
2109 			/* memcpy from input buffer into aligned buffer */
2110 			memcpy(aligned_buf, buf, len);
2111 			buf += len;
2112 			cnt -= len;
2113 			/* push data from aligned buffer into fifo */
2114 			for (i = 0; i < items; ++i)
2115 				mci_fifo_writew(host->fifo_reg, aligned_buf[i]);
2116 		}
2117 	} else
2118 #endif
2119 	{
2120 		u16 *pdata = buf;
2121 
2122 		for (; cnt >= 2; cnt -= 2)
2123 			mci_fifo_writew(host->fifo_reg, *pdata++);
2124 		buf = pdata;
2125 	}
2126 	/* put anything remaining in the part_buf */
2127 	if (cnt) {
2128 		dw_mci_set_part_bytes(host, buf, cnt);
2129 		 /* Push data if we have reached the expected data length */
2130 		if ((data->bytes_xfered + init_cnt) ==
2131 		    (data->blksz * data->blocks))
2132 			mci_fifo_writew(host->fifo_reg, host->part_buf16);
2133 	}
2134 }
2135 
2136 static void dw_mci_pull_data16(struct dw_mci *host, void *buf, int cnt)
2137 {
2138 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2139 	if (unlikely((unsigned long)buf & 0x1)) {
2140 		while (cnt >= 2) {
2141 			/* pull data from fifo into aligned buffer */
2142 			u16 aligned_buf[64];
2143 			int len = min(cnt & -2, (int)sizeof(aligned_buf));
2144 			int items = len >> 1;
2145 			int i;
2146 
2147 			for (i = 0; i < items; ++i)
2148 				aligned_buf[i] = mci_fifo_readw(host->fifo_reg);
2149 			/* memcpy from aligned buffer into output buffer */
2150 			memcpy(buf, aligned_buf, len);
2151 			buf += len;
2152 			cnt -= len;
2153 		}
2154 	} else
2155 #endif
2156 	{
2157 		u16 *pdata = buf;
2158 
2159 		for (; cnt >= 2; cnt -= 2)
2160 			*pdata++ = mci_fifo_readw(host->fifo_reg);
2161 		buf = pdata;
2162 	}
2163 	if (cnt) {
2164 		host->part_buf16 = mci_fifo_readw(host->fifo_reg);
2165 		dw_mci_pull_final_bytes(host, buf, cnt);
2166 	}
2167 }
2168 
2169 static void dw_mci_push_data32(struct dw_mci *host, void *buf, int cnt)
2170 {
2171 	struct mmc_data *data = host->data;
2172 	int init_cnt = cnt;
2173 
2174 	/* try and push anything in the part_buf */
2175 	if (unlikely(host->part_buf_count)) {
2176 		int len = dw_mci_push_part_bytes(host, buf, cnt);
2177 
2178 		buf += len;
2179 		cnt -= len;
2180 		if (host->part_buf_count == 4) {
2181 			mci_fifo_writel(host->fifo_reg,	host->part_buf32);
2182 			host->part_buf_count = 0;
2183 		}
2184 	}
2185 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2186 	if (unlikely((unsigned long)buf & 0x3)) {
2187 		while (cnt >= 4) {
2188 			u32 aligned_buf[32];
2189 			int len = min(cnt & -4, (int)sizeof(aligned_buf));
2190 			int items = len >> 2;
2191 			int i;
2192 			/* memcpy from input buffer into aligned buffer */
2193 			memcpy(aligned_buf, buf, len);
2194 			buf += len;
2195 			cnt -= len;
2196 			/* push data from aligned buffer into fifo */
2197 			for (i = 0; i < items; ++i)
2198 				mci_fifo_writel(host->fifo_reg,	aligned_buf[i]);
2199 		}
2200 	} else
2201 #endif
2202 	{
2203 		u32 *pdata = buf;
2204 
2205 		for (; cnt >= 4; cnt -= 4)
2206 			mci_fifo_writel(host->fifo_reg, *pdata++);
2207 		buf = pdata;
2208 	}
2209 	/* put anything remaining in the part_buf */
2210 	if (cnt) {
2211 		dw_mci_set_part_bytes(host, buf, cnt);
2212 		 /* Push data if we have reached the expected data length */
2213 		if ((data->bytes_xfered + init_cnt) ==
2214 		    (data->blksz * data->blocks))
2215 			mci_fifo_writel(host->fifo_reg, host->part_buf32);
2216 	}
2217 }
2218 
2219 static void dw_mci_pull_data32(struct dw_mci *host, void *buf, int cnt)
2220 {
2221 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2222 	if (unlikely((unsigned long)buf & 0x3)) {
2223 		while (cnt >= 4) {
2224 			/* pull data from fifo into aligned buffer */
2225 			u32 aligned_buf[32];
2226 			int len = min(cnt & -4, (int)sizeof(aligned_buf));
2227 			int items = len >> 2;
2228 			int i;
2229 
2230 			for (i = 0; i < items; ++i)
2231 				aligned_buf[i] = mci_fifo_readl(host->fifo_reg);
2232 			/* memcpy from aligned buffer into output buffer */
2233 			memcpy(buf, aligned_buf, len);
2234 			buf += len;
2235 			cnt -= len;
2236 		}
2237 	} else
2238 #endif
2239 	{
2240 		u32 *pdata = buf;
2241 
2242 		for (; cnt >= 4; cnt -= 4)
2243 			*pdata++ = mci_fifo_readl(host->fifo_reg);
2244 		buf = pdata;
2245 	}
2246 	if (cnt) {
2247 		host->part_buf32 = mci_fifo_readl(host->fifo_reg);
2248 		dw_mci_pull_final_bytes(host, buf, cnt);
2249 	}
2250 }
2251 
2252 static void dw_mci_push_data64(struct dw_mci *host, void *buf, int cnt)
2253 {
2254 	struct mmc_data *data = host->data;
2255 	int init_cnt = cnt;
2256 
2257 	/* try and push anything in the part_buf */
2258 	if (unlikely(host->part_buf_count)) {
2259 		int len = dw_mci_push_part_bytes(host, buf, cnt);
2260 
2261 		buf += len;
2262 		cnt -= len;
2263 
2264 		if (host->part_buf_count == 8) {
2265 			mci_fifo_writeq(host->fifo_reg,	host->part_buf);
2266 			host->part_buf_count = 0;
2267 		}
2268 	}
2269 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2270 	if (unlikely((unsigned long)buf & 0x7)) {
2271 		while (cnt >= 8) {
2272 			u64 aligned_buf[16];
2273 			int len = min(cnt & -8, (int)sizeof(aligned_buf));
2274 			int items = len >> 3;
2275 			int i;
2276 			/* memcpy from input buffer into aligned buffer */
2277 			memcpy(aligned_buf, buf, len);
2278 			buf += len;
2279 			cnt -= len;
2280 			/* push data from aligned buffer into fifo */
2281 			for (i = 0; i < items; ++i)
2282 				mci_fifo_writeq(host->fifo_reg,	aligned_buf[i]);
2283 		}
2284 	} else
2285 #endif
2286 	{
2287 		u64 *pdata = buf;
2288 
2289 		for (; cnt >= 8; cnt -= 8)
2290 			mci_fifo_writeq(host->fifo_reg, *pdata++);
2291 		buf = pdata;
2292 	}
2293 	/* put anything remaining in the part_buf */
2294 	if (cnt) {
2295 		dw_mci_set_part_bytes(host, buf, cnt);
2296 		/* Push data if we have reached the expected data length */
2297 		if ((data->bytes_xfered + init_cnt) ==
2298 		    (data->blksz * data->blocks))
2299 			mci_fifo_writeq(host->fifo_reg, host->part_buf);
2300 	}
2301 }
2302 
2303 static void dw_mci_pull_data64(struct dw_mci *host, void *buf, int cnt)
2304 {
2305 #ifndef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
2306 	if (unlikely((unsigned long)buf & 0x7)) {
2307 		while (cnt >= 8) {
2308 			/* pull data from fifo into aligned buffer */
2309 			u64 aligned_buf[16];
2310 			int len = min(cnt & -8, (int)sizeof(aligned_buf));
2311 			int items = len >> 3;
2312 			int i;
2313 
2314 			for (i = 0; i < items; ++i)
2315 				aligned_buf[i] = mci_fifo_readq(host->fifo_reg);
2316 
2317 			/* memcpy from aligned buffer into output buffer */
2318 			memcpy(buf, aligned_buf, len);
2319 			buf += len;
2320 			cnt -= len;
2321 		}
2322 	} else
2323 #endif
2324 	{
2325 		u64 *pdata = buf;
2326 
2327 		for (; cnt >= 8; cnt -= 8)
2328 			*pdata++ = mci_fifo_readq(host->fifo_reg);
2329 		buf = pdata;
2330 	}
2331 	if (cnt) {
2332 		host->part_buf = mci_fifo_readq(host->fifo_reg);
2333 		dw_mci_pull_final_bytes(host, buf, cnt);
2334 	}
2335 }
2336 
2337 static void dw_mci_pull_data(struct dw_mci *host, void *buf, int cnt)
2338 {
2339 	int len;
2340 
2341 	/* get remaining partial bytes */
2342 	len = dw_mci_pull_part_bytes(host, buf, cnt);
2343 	if (unlikely(len == cnt))
2344 		return;
2345 	buf += len;
2346 	cnt -= len;
2347 
2348 	/* get the rest of the data */
2349 	host->pull_data(host, buf, cnt);
2350 }
2351 
2352 static void dw_mci_read_data_pio(struct dw_mci *host, bool dto)
2353 {
2354 	struct sg_mapping_iter *sg_miter = &host->sg_miter;
2355 	void *buf;
2356 	unsigned int offset;
2357 	struct mmc_data	*data = host->data;
2358 	int shift = host->data_shift;
2359 	u32 status;
2360 	unsigned int len;
2361 	unsigned int remain, fcnt;
2362 
2363 	do {
2364 		if (!sg_miter_next(sg_miter))
2365 			goto done;
2366 
2367 		host->sg = sg_miter->piter.sg;
2368 		buf = sg_miter->addr;
2369 		remain = sg_miter->length;
2370 		offset = 0;
2371 
2372 		do {
2373 			fcnt = (SDMMC_GET_FCNT(mci_readl(host, STATUS))
2374 					<< shift) + host->part_buf_count;
2375 			len = min(remain, fcnt);
2376 			if (!len)
2377 				break;
2378 			dw_mci_pull_data(host, (void *)(buf + offset), len);
2379 			data->bytes_xfered += len;
2380 			offset += len;
2381 			remain -= len;
2382 		} while (remain);
2383 
2384 		sg_miter->consumed = offset;
2385 		status = mci_readl(host, MINTSTS);
2386 		mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
2387 	/* if the RXDR is ready read again */
2388 	} while ((status & SDMMC_INT_RXDR) ||
2389 		 (dto && SDMMC_GET_FCNT(mci_readl(host, STATUS))));
2390 
2391 	if (!remain) {
2392 		if (!sg_miter_next(sg_miter))
2393 			goto done;
2394 		sg_miter->consumed = 0;
2395 	}
2396 	sg_miter_stop(sg_miter);
2397 	return;
2398 
2399 done:
2400 	sg_miter_stop(sg_miter);
2401 	host->sg = NULL;
2402 	smp_wmb(); /* drain writebuffer */
2403 	set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
2404 }
2405 
2406 static void dw_mci_write_data_pio(struct dw_mci *host)
2407 {
2408 	struct sg_mapping_iter *sg_miter = &host->sg_miter;
2409 	void *buf;
2410 	unsigned int offset;
2411 	struct mmc_data	*data = host->data;
2412 	int shift = host->data_shift;
2413 	u32 status;
2414 	unsigned int len;
2415 	unsigned int fifo_depth = host->fifo_depth;
2416 	unsigned int remain, fcnt;
2417 
2418 	do {
2419 		if (!sg_miter_next(sg_miter))
2420 			goto done;
2421 
2422 		host->sg = sg_miter->piter.sg;
2423 		buf = sg_miter->addr;
2424 		remain = sg_miter->length;
2425 		offset = 0;
2426 
2427 		do {
2428 			fcnt = ((fifo_depth -
2429 				 SDMMC_GET_FCNT(mci_readl(host, STATUS)))
2430 					<< shift) - host->part_buf_count;
2431 			len = min(remain, fcnt);
2432 			if (!len)
2433 				break;
2434 			host->push_data(host, (void *)(buf + offset), len);
2435 			data->bytes_xfered += len;
2436 			offset += len;
2437 			remain -= len;
2438 		} while (remain);
2439 
2440 		sg_miter->consumed = offset;
2441 		status = mci_readl(host, MINTSTS);
2442 		mci_writel(host, RINTSTS, SDMMC_INT_TXDR);
2443 	} while (status & SDMMC_INT_TXDR); /* if TXDR write again */
2444 
2445 	if (!remain) {
2446 		if (!sg_miter_next(sg_miter))
2447 			goto done;
2448 		sg_miter->consumed = 0;
2449 	}
2450 	sg_miter_stop(sg_miter);
2451 	return;
2452 
2453 done:
2454 	sg_miter_stop(sg_miter);
2455 	host->sg = NULL;
2456 	smp_wmb(); /* drain writebuffer */
2457 	set_bit(EVENT_XFER_COMPLETE, &host->pending_events);
2458 }
2459 
2460 static void dw_mci_cmd_interrupt(struct dw_mci *host, u32 status)
2461 {
2462 	if (!host->cmd_status)
2463 		host->cmd_status = status;
2464 
2465 	smp_wmb(); /* drain writebuffer */
2466 
2467 	set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
2468 	tasklet_schedule(&host->tasklet);
2469 }
2470 
2471 static void dw_mci_handle_cd(struct dw_mci *host)
2472 {
2473 	int i;
2474 
2475 	for (i = 0; i < host->num_slots; i++) {
2476 		struct dw_mci_slot *slot = host->slot[i];
2477 
2478 		if (!slot)
2479 			continue;
2480 
2481 		if (slot->mmc->ops->card_event)
2482 			slot->mmc->ops->card_event(slot->mmc);
2483 		mmc_detect_change(slot->mmc,
2484 			msecs_to_jiffies(host->pdata->detect_delay_ms));
2485 	}
2486 }
2487 
2488 static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
2489 {
2490 	struct dw_mci *host = dev_id;
2491 	u32 pending;
2492 	int i;
2493 
2494 	pending = mci_readl(host, MINTSTS); /* read-only mask reg */
2495 
2496 	if (pending) {
2497 		/* Check volt switch first, since it can look like an error */
2498 		if ((host->state == STATE_SENDING_CMD11) &&
2499 		    (pending & SDMMC_INT_VOLT_SWITCH)) {
2500 			unsigned long irqflags;
2501 
2502 			mci_writel(host, RINTSTS, SDMMC_INT_VOLT_SWITCH);
2503 			pending &= ~SDMMC_INT_VOLT_SWITCH;
2504 
2505 			/*
2506 			 * Hold the lock; we know cmd11_timer can't be kicked
2507 			 * off after the lock is released, so safe to delete.
2508 			 */
2509 			spin_lock_irqsave(&host->irq_lock, irqflags);
2510 			dw_mci_cmd_interrupt(host, pending);
2511 			spin_unlock_irqrestore(&host->irq_lock, irqflags);
2512 
2513 			del_timer(&host->cmd11_timer);
2514 		}
2515 
2516 		if (pending & DW_MCI_CMD_ERROR_FLAGS) {
2517 			mci_writel(host, RINTSTS, DW_MCI_CMD_ERROR_FLAGS);
2518 			host->cmd_status = pending;
2519 			smp_wmb(); /* drain writebuffer */
2520 			set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
2521 		}
2522 
2523 		if (pending & DW_MCI_DATA_ERROR_FLAGS) {
2524 			/* if there is an error report DATA_ERROR */
2525 			mci_writel(host, RINTSTS, DW_MCI_DATA_ERROR_FLAGS);
2526 			host->data_status = pending;
2527 			smp_wmb(); /* drain writebuffer */
2528 			set_bit(EVENT_DATA_ERROR, &host->pending_events);
2529 			tasklet_schedule(&host->tasklet);
2530 		}
2531 
2532 		if (pending & SDMMC_INT_DATA_OVER) {
2533 			del_timer(&host->dto_timer);
2534 
2535 			mci_writel(host, RINTSTS, SDMMC_INT_DATA_OVER);
2536 			if (!host->data_status)
2537 				host->data_status = pending;
2538 			smp_wmb(); /* drain writebuffer */
2539 			if (host->dir_status == DW_MCI_RECV_STATUS) {
2540 				if (host->sg != NULL)
2541 					dw_mci_read_data_pio(host, true);
2542 			}
2543 			set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
2544 			tasklet_schedule(&host->tasklet);
2545 		}
2546 
2547 		if (pending & SDMMC_INT_RXDR) {
2548 			mci_writel(host, RINTSTS, SDMMC_INT_RXDR);
2549 			if (host->dir_status == DW_MCI_RECV_STATUS && host->sg)
2550 				dw_mci_read_data_pio(host, false);
2551 		}
2552 
2553 		if (pending & SDMMC_INT_TXDR) {
2554 			mci_writel(host, RINTSTS, SDMMC_INT_TXDR);
2555 			if (host->dir_status == DW_MCI_SEND_STATUS && host->sg)
2556 				dw_mci_write_data_pio(host);
2557 		}
2558 
2559 		if (pending & SDMMC_INT_CMD_DONE) {
2560 			mci_writel(host, RINTSTS, SDMMC_INT_CMD_DONE);
2561 			dw_mci_cmd_interrupt(host, pending);
2562 		}
2563 
2564 		if (pending & SDMMC_INT_CD) {
2565 			mci_writel(host, RINTSTS, SDMMC_INT_CD);
2566 			dw_mci_handle_cd(host);
2567 		}
2568 
2569 		/* Handle SDIO Interrupts */
2570 		for (i = 0; i < host->num_slots; i++) {
2571 			struct dw_mci_slot *slot = host->slot[i];
2572 
2573 			if (!slot)
2574 				continue;
2575 
2576 			if (pending & SDMMC_INT_SDIO(slot->sdio_id)) {
2577 				mci_writel(host, RINTSTS,
2578 					   SDMMC_INT_SDIO(slot->sdio_id));
2579 				mmc_signal_sdio_irq(slot->mmc);
2580 			}
2581 		}
2582 
2583 	}
2584 
2585 	if (host->use_dma != TRANS_MODE_IDMAC)
2586 		return IRQ_HANDLED;
2587 
2588 	/* Handle IDMA interrupts */
2589 	if (host->dma_64bit_address == 1) {
2590 		pending = mci_readl(host, IDSTS64);
2591 		if (pending & (SDMMC_IDMAC_INT_TI | SDMMC_IDMAC_INT_RI)) {
2592 			mci_writel(host, IDSTS64, SDMMC_IDMAC_INT_TI |
2593 							SDMMC_IDMAC_INT_RI);
2594 			mci_writel(host, IDSTS64, SDMMC_IDMAC_INT_NI);
2595 			if (!test_bit(EVENT_DATA_ERROR, &host->pending_events))
2596 				host->dma_ops->complete((void *)host);
2597 		}
2598 	} else {
2599 		pending = mci_readl(host, IDSTS);
2600 		if (pending & (SDMMC_IDMAC_INT_TI | SDMMC_IDMAC_INT_RI)) {
2601 			mci_writel(host, IDSTS, SDMMC_IDMAC_INT_TI |
2602 							SDMMC_IDMAC_INT_RI);
2603 			mci_writel(host, IDSTS, SDMMC_IDMAC_INT_NI);
2604 			if (!test_bit(EVENT_DATA_ERROR, &host->pending_events))
2605 				host->dma_ops->complete((void *)host);
2606 		}
2607 	}
2608 
2609 	return IRQ_HANDLED;
2610 }
2611 
2612 static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
2613 {
2614 	struct mmc_host *mmc;
2615 	struct dw_mci_slot *slot;
2616 	const struct dw_mci_drv_data *drv_data = host->drv_data;
2617 	int ctrl_id, ret;
2618 	u32 freq[2];
2619 
2620 	mmc = mmc_alloc_host(sizeof(struct dw_mci_slot), host->dev);
2621 	if (!mmc)
2622 		return -ENOMEM;
2623 
2624 	slot = mmc_priv(mmc);
2625 	slot->id = id;
2626 	slot->sdio_id = host->sdio_id0 + id;
2627 	slot->mmc = mmc;
2628 	slot->host = host;
2629 	host->slot[id] = slot;
2630 
2631 	mmc->ops = &dw_mci_ops;
2632 	if (of_property_read_u32_array(host->dev->of_node,
2633 				       "clock-freq-min-max", freq, 2)) {
2634 		mmc->f_min = DW_MCI_FREQ_MIN;
2635 		mmc->f_max = DW_MCI_FREQ_MAX;
2636 	} else {
2637 		dev_info(host->dev,
2638 			"'clock-freq-min-max' property was deprecated.\n");
2639 		mmc->f_min = freq[0];
2640 		mmc->f_max = freq[1];
2641 	}
2642 
2643 	/*if there are external regulators, get them*/
2644 	ret = mmc_regulator_get_supply(mmc);
2645 	if (ret == -EPROBE_DEFER)
2646 		goto err_host_allocated;
2647 
2648 	if (!mmc->ocr_avail)
2649 		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
2650 
2651 	if (host->pdata->caps)
2652 		mmc->caps = host->pdata->caps;
2653 
2654 	/*
2655 	 * Support MMC_CAP_ERASE by default.
2656 	 * It needs to use trim/discard/erase commands.
2657 	 */
2658 	mmc->caps |= MMC_CAP_ERASE;
2659 
2660 	if (host->pdata->pm_caps)
2661 		mmc->pm_caps = host->pdata->pm_caps;
2662 
2663 	if (host->dev->of_node) {
2664 		ctrl_id = of_alias_get_id(host->dev->of_node, "mshc");
2665 		if (ctrl_id < 0)
2666 			ctrl_id = 0;
2667 	} else {
2668 		ctrl_id = to_platform_device(host->dev)->id;
2669 	}
2670 	if (drv_data && drv_data->caps)
2671 		mmc->caps |= drv_data->caps[ctrl_id];
2672 
2673 	if (host->pdata->caps2)
2674 		mmc->caps2 = host->pdata->caps2;
2675 
2676 	ret = mmc_of_parse(mmc);
2677 	if (ret)
2678 		goto err_host_allocated;
2679 
2680 	/* Useful defaults if platform data is unset. */
2681 	if (host->use_dma == TRANS_MODE_IDMAC) {
2682 		mmc->max_segs = host->ring_size;
2683 		mmc->max_blk_size = 65535;
2684 		mmc->max_seg_size = 0x1000;
2685 		mmc->max_req_size = mmc->max_seg_size * host->ring_size;
2686 		mmc->max_blk_count = mmc->max_req_size / 512;
2687 	} else if (host->use_dma == TRANS_MODE_EDMAC) {
2688 		mmc->max_segs = 64;
2689 		mmc->max_blk_size = 65535;
2690 		mmc->max_blk_count = 65535;
2691 		mmc->max_req_size =
2692 				mmc->max_blk_size * mmc->max_blk_count;
2693 		mmc->max_seg_size = mmc->max_req_size;
2694 	} else {
2695 		/* TRANS_MODE_PIO */
2696 		mmc->max_segs = 64;
2697 		mmc->max_blk_size = 65535; /* BLKSIZ is 16 bits */
2698 		mmc->max_blk_count = 512;
2699 		mmc->max_req_size = mmc->max_blk_size *
2700 				    mmc->max_blk_count;
2701 		mmc->max_seg_size = mmc->max_req_size;
2702 	}
2703 
2704 	dw_mci_get_cd(mmc);
2705 
2706 	ret = mmc_add_host(mmc);
2707 	if (ret)
2708 		goto err_host_allocated;
2709 
2710 #if defined(CONFIG_DEBUG_FS)
2711 	dw_mci_init_debugfs(slot);
2712 #endif
2713 
2714 	return 0;
2715 
2716 err_host_allocated:
2717 	mmc_free_host(mmc);
2718 	return ret;
2719 }
2720 
2721 static void dw_mci_cleanup_slot(struct dw_mci_slot *slot, unsigned int id)
2722 {
2723 	/* Debugfs stuff is cleaned up by mmc core */
2724 	mmc_remove_host(slot->mmc);
2725 	slot->host->slot[id] = NULL;
2726 	mmc_free_host(slot->mmc);
2727 }
2728 
2729 static void dw_mci_init_dma(struct dw_mci *host)
2730 {
2731 	int addr_config;
2732 	struct device *dev = host->dev;
2733 	struct device_node *np = dev->of_node;
2734 
2735 	/*
2736 	* Check tansfer mode from HCON[17:16]
2737 	* Clear the ambiguous description of dw_mmc databook:
2738 	* 2b'00: No DMA Interface -> Actually means using Internal DMA block
2739 	* 2b'01: DesignWare DMA Interface -> Synopsys DW-DMA block
2740 	* 2b'10: Generic DMA Interface -> non-Synopsys generic DMA block
2741 	* 2b'11: Non DW DMA Interface -> pio only
2742 	* Compared to DesignWare DMA Interface, Generic DMA Interface has a
2743 	* simpler request/acknowledge handshake mechanism and both of them
2744 	* are regarded as external dma master for dw_mmc.
2745 	*/
2746 	host->use_dma = SDMMC_GET_TRANS_MODE(mci_readl(host, HCON));
2747 	if (host->use_dma == DMA_INTERFACE_IDMA) {
2748 		host->use_dma = TRANS_MODE_IDMAC;
2749 	} else if (host->use_dma == DMA_INTERFACE_DWDMA ||
2750 		   host->use_dma == DMA_INTERFACE_GDMA) {
2751 		host->use_dma = TRANS_MODE_EDMAC;
2752 	} else {
2753 		goto no_dma;
2754 	}
2755 
2756 	/* Determine which DMA interface to use */
2757 	if (host->use_dma == TRANS_MODE_IDMAC) {
2758 		/*
2759 		* Check ADDR_CONFIG bit in HCON to find
2760 		* IDMAC address bus width
2761 		*/
2762 		addr_config = SDMMC_GET_ADDR_CONFIG(mci_readl(host, HCON));
2763 
2764 		if (addr_config == 1) {
2765 			/* host supports IDMAC in 64-bit address mode */
2766 			host->dma_64bit_address = 1;
2767 			dev_info(host->dev,
2768 				 "IDMAC supports 64-bit address mode.\n");
2769 			if (!dma_set_mask(host->dev, DMA_BIT_MASK(64)))
2770 				dma_set_coherent_mask(host->dev,
2771 						      DMA_BIT_MASK(64));
2772 		} else {
2773 			/* host supports IDMAC in 32-bit address mode */
2774 			host->dma_64bit_address = 0;
2775 			dev_info(host->dev,
2776 				 "IDMAC supports 32-bit address mode.\n");
2777 		}
2778 
2779 		/* Alloc memory for sg translation */
2780 		host->sg_cpu = dmam_alloc_coherent(host->dev,
2781 						   DESC_RING_BUF_SZ,
2782 						   &host->sg_dma, GFP_KERNEL);
2783 		if (!host->sg_cpu) {
2784 			dev_err(host->dev,
2785 				"%s: could not alloc DMA memory\n",
2786 				__func__);
2787 			goto no_dma;
2788 		}
2789 
2790 		host->dma_ops = &dw_mci_idmac_ops;
2791 		dev_info(host->dev, "Using internal DMA controller.\n");
2792 	} else {
2793 		/* TRANS_MODE_EDMAC: check dma bindings again */
2794 		if ((of_property_count_strings(np, "dma-names") < 0) ||
2795 		    (!of_find_property(np, "dmas", NULL))) {
2796 			goto no_dma;
2797 		}
2798 		host->dma_ops = &dw_mci_edmac_ops;
2799 		dev_info(host->dev, "Using external DMA controller.\n");
2800 	}
2801 
2802 	if (host->dma_ops->init && host->dma_ops->start &&
2803 	    host->dma_ops->stop && host->dma_ops->cleanup) {
2804 		if (host->dma_ops->init(host)) {
2805 			dev_err(host->dev, "%s: Unable to initialize DMA Controller.\n",
2806 				__func__);
2807 			goto no_dma;
2808 		}
2809 	} else {
2810 		dev_err(host->dev, "DMA initialization not found.\n");
2811 		goto no_dma;
2812 	}
2813 
2814 	return;
2815 
2816 no_dma:
2817 	dev_info(host->dev, "Using PIO mode.\n");
2818 	host->use_dma = TRANS_MODE_PIO;
2819 }
2820 
2821 static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset)
2822 {
2823 	unsigned long timeout = jiffies + msecs_to_jiffies(500);
2824 	u32 ctrl;
2825 
2826 	ctrl = mci_readl(host, CTRL);
2827 	ctrl |= reset;
2828 	mci_writel(host, CTRL, ctrl);
2829 
2830 	/* wait till resets clear */
2831 	do {
2832 		ctrl = mci_readl(host, CTRL);
2833 		if (!(ctrl & reset))
2834 			return true;
2835 	} while (time_before(jiffies, timeout));
2836 
2837 	dev_err(host->dev,
2838 		"Timeout resetting block (ctrl reset %#x)\n",
2839 		ctrl & reset);
2840 
2841 	return false;
2842 }
2843 
2844 static bool dw_mci_reset(struct dw_mci *host)
2845 {
2846 	u32 flags = SDMMC_CTRL_RESET | SDMMC_CTRL_FIFO_RESET;
2847 	bool ret = false;
2848 
2849 	/*
2850 	 * Reseting generates a block interrupt, hence setting
2851 	 * the scatter-gather pointer to NULL.
2852 	 */
2853 	if (host->sg) {
2854 		sg_miter_stop(&host->sg_miter);
2855 		host->sg = NULL;
2856 	}
2857 
2858 	if (host->use_dma)
2859 		flags |= SDMMC_CTRL_DMA_RESET;
2860 
2861 	if (dw_mci_ctrl_reset(host, flags)) {
2862 		/*
2863 		 * In all cases we clear the RAWINTS register to clear any
2864 		 * interrupts.
2865 		 */
2866 		mci_writel(host, RINTSTS, 0xFFFFFFFF);
2867 
2868 		/* if using dma we wait for dma_req to clear */
2869 		if (host->use_dma) {
2870 			unsigned long timeout = jiffies + msecs_to_jiffies(500);
2871 			u32 status;
2872 
2873 			do {
2874 				status = mci_readl(host, STATUS);
2875 				if (!(status & SDMMC_STATUS_DMA_REQ))
2876 					break;
2877 				cpu_relax();
2878 			} while (time_before(jiffies, timeout));
2879 
2880 			if (status & SDMMC_STATUS_DMA_REQ) {
2881 				dev_err(host->dev,
2882 					"%s: Timeout waiting for dma_req to clear during reset\n",
2883 					__func__);
2884 				goto ciu_out;
2885 			}
2886 
2887 			/* when using DMA next we reset the fifo again */
2888 			if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_FIFO_RESET))
2889 				goto ciu_out;
2890 		}
2891 	} else {
2892 		/* if the controller reset bit did clear, then set clock regs */
2893 		if (!(mci_readl(host, CTRL) & SDMMC_CTRL_RESET)) {
2894 			dev_err(host->dev,
2895 				"%s: fifo/dma reset bits didn't clear but ciu was reset, doing clock update\n",
2896 				__func__);
2897 			goto ciu_out;
2898 		}
2899 	}
2900 
2901 	if (host->use_dma == TRANS_MODE_IDMAC)
2902 		/* It is also recommended that we reset and reprogram idmac */
2903 		dw_mci_idmac_reset(host);
2904 
2905 	ret = true;
2906 
2907 ciu_out:
2908 	/* After a CTRL reset we need to have CIU set clock registers  */
2909 	mci_send_cmd(host->cur_slot, SDMMC_CMD_UPD_CLK, 0);
2910 
2911 	return ret;
2912 }
2913 
2914 static void dw_mci_cmd11_timer(unsigned long arg)
2915 {
2916 	struct dw_mci *host = (struct dw_mci *)arg;
2917 
2918 	if (host->state != STATE_SENDING_CMD11) {
2919 		dev_warn(host->dev, "Unexpected CMD11 timeout\n");
2920 		return;
2921 	}
2922 
2923 	host->cmd_status = SDMMC_INT_RTO;
2924 	set_bit(EVENT_CMD_COMPLETE, &host->pending_events);
2925 	tasklet_schedule(&host->tasklet);
2926 }
2927 
2928 static void dw_mci_dto_timer(unsigned long arg)
2929 {
2930 	struct dw_mci *host = (struct dw_mci *)arg;
2931 
2932 	switch (host->state) {
2933 	case STATE_SENDING_DATA:
2934 	case STATE_DATA_BUSY:
2935 		/*
2936 		 * If DTO interrupt does NOT come in sending data state,
2937 		 * we should notify the driver to terminate current transfer
2938 		 * and report a data timeout to the core.
2939 		 */
2940 		host->data_status = SDMMC_INT_DRTO;
2941 		set_bit(EVENT_DATA_ERROR, &host->pending_events);
2942 		set_bit(EVENT_DATA_COMPLETE, &host->pending_events);
2943 		tasklet_schedule(&host->tasklet);
2944 		break;
2945 	default:
2946 		break;
2947 	}
2948 }
2949 
2950 #ifdef CONFIG_OF
2951 static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host)
2952 {
2953 	struct dw_mci_board *pdata;
2954 	struct device *dev = host->dev;
2955 	struct device_node *np = dev->of_node;
2956 	const struct dw_mci_drv_data *drv_data = host->drv_data;
2957 	int ret;
2958 	u32 clock_frequency;
2959 
2960 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
2961 	if (!pdata)
2962 		return ERR_PTR(-ENOMEM);
2963 
2964 	/* find reset controller when exist */
2965 	pdata->rstc = devm_reset_control_get_optional(dev, "reset");
2966 	if (IS_ERR(pdata->rstc)) {
2967 		if (PTR_ERR(pdata->rstc) == -EPROBE_DEFER)
2968 			return ERR_PTR(-EPROBE_DEFER);
2969 	}
2970 
2971 	/* find out number of slots supported */
2972 	of_property_read_u32(np, "num-slots", &pdata->num_slots);
2973 
2974 	if (of_property_read_u32(np, "fifo-depth", &pdata->fifo_depth))
2975 		dev_info(dev,
2976 			 "fifo-depth property not found, using value of FIFOTH register as default\n");
2977 
2978 	of_property_read_u32(np, "card-detect-delay", &pdata->detect_delay_ms);
2979 
2980 	if (!of_property_read_u32(np, "clock-frequency", &clock_frequency))
2981 		pdata->bus_hz = clock_frequency;
2982 
2983 	if (drv_data && drv_data->parse_dt) {
2984 		ret = drv_data->parse_dt(host);
2985 		if (ret)
2986 			return ERR_PTR(ret);
2987 	}
2988 
2989 	return pdata;
2990 }
2991 
2992 #else /* CONFIG_OF */
2993 static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host)
2994 {
2995 	return ERR_PTR(-EINVAL);
2996 }
2997 #endif /* CONFIG_OF */
2998 
2999 static void dw_mci_enable_cd(struct dw_mci *host)
3000 {
3001 	unsigned long irqflags;
3002 	u32 temp;
3003 	int i;
3004 	struct dw_mci_slot *slot;
3005 
3006 	/*
3007 	 * No need for CD if all slots have a non-error GPIO
3008 	 * as well as broken card detection is found.
3009 	 */
3010 	for (i = 0; i < host->num_slots; i++) {
3011 		slot = host->slot[i];
3012 		if (slot->mmc->caps & MMC_CAP_NEEDS_POLL)
3013 			return;
3014 
3015 		if (mmc_gpio_get_cd(slot->mmc) < 0)
3016 			break;
3017 	}
3018 	if (i == host->num_slots)
3019 		return;
3020 
3021 	spin_lock_irqsave(&host->irq_lock, irqflags);
3022 	temp = mci_readl(host, INTMASK);
3023 	temp  |= SDMMC_INT_CD;
3024 	mci_writel(host, INTMASK, temp);
3025 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
3026 }
3027 
3028 int dw_mci_probe(struct dw_mci *host)
3029 {
3030 	const struct dw_mci_drv_data *drv_data = host->drv_data;
3031 	int width, i, ret = 0;
3032 	u32 fifo_size;
3033 	int init_slots = 0;
3034 
3035 	if (!host->pdata) {
3036 		host->pdata = dw_mci_parse_dt(host);
3037 		if (PTR_ERR(host->pdata) == -EPROBE_DEFER) {
3038 			return -EPROBE_DEFER;
3039 		} else if (IS_ERR(host->pdata)) {
3040 			dev_err(host->dev, "platform data not available\n");
3041 			return -EINVAL;
3042 		}
3043 	}
3044 
3045 	host->biu_clk = devm_clk_get(host->dev, "biu");
3046 	if (IS_ERR(host->biu_clk)) {
3047 		dev_dbg(host->dev, "biu clock not available\n");
3048 	} else {
3049 		ret = clk_prepare_enable(host->biu_clk);
3050 		if (ret) {
3051 			dev_err(host->dev, "failed to enable biu clock\n");
3052 			return ret;
3053 		}
3054 	}
3055 
3056 	host->ciu_clk = devm_clk_get(host->dev, "ciu");
3057 	if (IS_ERR(host->ciu_clk)) {
3058 		dev_dbg(host->dev, "ciu clock not available\n");
3059 		host->bus_hz = host->pdata->bus_hz;
3060 	} else {
3061 		ret = clk_prepare_enable(host->ciu_clk);
3062 		if (ret) {
3063 			dev_err(host->dev, "failed to enable ciu clock\n");
3064 			goto err_clk_biu;
3065 		}
3066 
3067 		if (host->pdata->bus_hz) {
3068 			ret = clk_set_rate(host->ciu_clk, host->pdata->bus_hz);
3069 			if (ret)
3070 				dev_warn(host->dev,
3071 					 "Unable to set bus rate to %uHz\n",
3072 					 host->pdata->bus_hz);
3073 		}
3074 		host->bus_hz = clk_get_rate(host->ciu_clk);
3075 	}
3076 
3077 	if (!host->bus_hz) {
3078 		dev_err(host->dev,
3079 			"Platform data must supply bus speed\n");
3080 		ret = -ENODEV;
3081 		goto err_clk_ciu;
3082 	}
3083 
3084 	if (drv_data && drv_data->init) {
3085 		ret = drv_data->init(host);
3086 		if (ret) {
3087 			dev_err(host->dev,
3088 				"implementation specific init failed\n");
3089 			goto err_clk_ciu;
3090 		}
3091 	}
3092 
3093 	if (!IS_ERR(host->pdata->rstc)) {
3094 		reset_control_assert(host->pdata->rstc);
3095 		usleep_range(10, 50);
3096 		reset_control_deassert(host->pdata->rstc);
3097 	}
3098 
3099 	setup_timer(&host->cmd11_timer,
3100 		    dw_mci_cmd11_timer, (unsigned long)host);
3101 
3102 	setup_timer(&host->dto_timer,
3103 		    dw_mci_dto_timer, (unsigned long)host);
3104 
3105 	spin_lock_init(&host->lock);
3106 	spin_lock_init(&host->irq_lock);
3107 	INIT_LIST_HEAD(&host->queue);
3108 
3109 	/*
3110 	 * Get the host data width - this assumes that HCON has been set with
3111 	 * the correct values.
3112 	 */
3113 	i = SDMMC_GET_HDATA_WIDTH(mci_readl(host, HCON));
3114 	if (!i) {
3115 		host->push_data = dw_mci_push_data16;
3116 		host->pull_data = dw_mci_pull_data16;
3117 		width = 16;
3118 		host->data_shift = 1;
3119 	} else if (i == 2) {
3120 		host->push_data = dw_mci_push_data64;
3121 		host->pull_data = dw_mci_pull_data64;
3122 		width = 64;
3123 		host->data_shift = 3;
3124 	} else {
3125 		/* Check for a reserved value, and warn if it is */
3126 		WARN((i != 1),
3127 		     "HCON reports a reserved host data width!\n"
3128 		     "Defaulting to 32-bit access.\n");
3129 		host->push_data = dw_mci_push_data32;
3130 		host->pull_data = dw_mci_pull_data32;
3131 		width = 32;
3132 		host->data_shift = 2;
3133 	}
3134 
3135 	/* Reset all blocks */
3136 	if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_ALL_RESET_FLAGS)) {
3137 		ret = -ENODEV;
3138 		goto err_clk_ciu;
3139 	}
3140 
3141 	host->dma_ops = host->pdata->dma_ops;
3142 	dw_mci_init_dma(host);
3143 
3144 	/* Clear the interrupts for the host controller */
3145 	mci_writel(host, RINTSTS, 0xFFFFFFFF);
3146 	mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */
3147 
3148 	/* Put in max timeout */
3149 	mci_writel(host, TMOUT, 0xFFFFFFFF);
3150 
3151 	/*
3152 	 * FIFO threshold settings  RxMark  = fifo_size / 2 - 1,
3153 	 *                          Tx Mark = fifo_size / 2 DMA Size = 8
3154 	 */
3155 	if (!host->pdata->fifo_depth) {
3156 		/*
3157 		 * Power-on value of RX_WMark is FIFO_DEPTH-1, but this may
3158 		 * have been overwritten by the bootloader, just like we're
3159 		 * about to do, so if you know the value for your hardware, you
3160 		 * should put it in the platform data.
3161 		 */
3162 		fifo_size = mci_readl(host, FIFOTH);
3163 		fifo_size = 1 + ((fifo_size >> 16) & 0xfff);
3164 	} else {
3165 		fifo_size = host->pdata->fifo_depth;
3166 	}
3167 	host->fifo_depth = fifo_size;
3168 	host->fifoth_val =
3169 		SDMMC_SET_FIFOTH(0x2, fifo_size / 2 - 1, fifo_size / 2);
3170 	mci_writel(host, FIFOTH, host->fifoth_val);
3171 
3172 	/* disable clock to CIU */
3173 	mci_writel(host, CLKENA, 0);
3174 	mci_writel(host, CLKSRC, 0);
3175 
3176 	/*
3177 	 * In 2.40a spec, Data offset is changed.
3178 	 * Need to check the version-id and set data-offset for DATA register.
3179 	 */
3180 	host->verid = SDMMC_GET_VERID(mci_readl(host, VERID));
3181 	dev_info(host->dev, "Version ID is %04x\n", host->verid);
3182 
3183 	if (host->verid < DW_MMC_240A)
3184 		host->fifo_reg = host->regs + DATA_OFFSET;
3185 	else
3186 		host->fifo_reg = host->regs + DATA_240A_OFFSET;
3187 
3188 	tasklet_init(&host->tasklet, dw_mci_tasklet_func, (unsigned long)host);
3189 	ret = devm_request_irq(host->dev, host->irq, dw_mci_interrupt,
3190 			       host->irq_flags, "dw-mci", host);
3191 	if (ret)
3192 		goto err_dmaunmap;
3193 
3194 	if (host->pdata->num_slots)
3195 		host->num_slots = host->pdata->num_slots;
3196 	else
3197 		host->num_slots = 1;
3198 
3199 	if (host->num_slots < 1 ||
3200 	    host->num_slots > SDMMC_GET_SLOT_NUM(mci_readl(host, HCON))) {
3201 		dev_err(host->dev,
3202 			"Platform data must supply correct num_slots.\n");
3203 		ret = -ENODEV;
3204 		goto err_clk_ciu;
3205 	}
3206 
3207 	/*
3208 	 * Enable interrupts for command done, data over, data empty,
3209 	 * receive ready and error such as transmit, receive timeout, crc error
3210 	 */
3211 	mci_writel(host, INTMASK, SDMMC_INT_CMD_DONE | SDMMC_INT_DATA_OVER |
3212 		   SDMMC_INT_TXDR | SDMMC_INT_RXDR |
3213 		   DW_MCI_ERROR_FLAGS);
3214 	/* Enable mci interrupt */
3215 	mci_writel(host, CTRL, SDMMC_CTRL_INT_ENABLE);
3216 
3217 	dev_info(host->dev,
3218 		 "DW MMC controller at irq %d,%d bit host data width,%u deep fifo\n",
3219 		 host->irq, width, fifo_size);
3220 
3221 	/* We need at least one slot to succeed */
3222 	for (i = 0; i < host->num_slots; i++) {
3223 		ret = dw_mci_init_slot(host, i);
3224 		if (ret)
3225 			dev_dbg(host->dev, "slot %d init failed\n", i);
3226 		else
3227 			init_slots++;
3228 	}
3229 
3230 	if (init_slots) {
3231 		dev_info(host->dev, "%d slots initialized\n", init_slots);
3232 	} else {
3233 		dev_dbg(host->dev,
3234 			"attempted to initialize %d slots, but failed on all\n",
3235 			host->num_slots);
3236 		goto err_dmaunmap;
3237 	}
3238 
3239 	/* Now that slots are all setup, we can enable card detect */
3240 	dw_mci_enable_cd(host);
3241 
3242 	return 0;
3243 
3244 err_dmaunmap:
3245 	if (host->use_dma && host->dma_ops->exit)
3246 		host->dma_ops->exit(host);
3247 
3248 	if (!IS_ERR(host->pdata->rstc))
3249 		reset_control_assert(host->pdata->rstc);
3250 
3251 err_clk_ciu:
3252 	clk_disable_unprepare(host->ciu_clk);
3253 
3254 err_clk_biu:
3255 	clk_disable_unprepare(host->biu_clk);
3256 
3257 	return ret;
3258 }
3259 EXPORT_SYMBOL(dw_mci_probe);
3260 
3261 void dw_mci_remove(struct dw_mci *host)
3262 {
3263 	int i;
3264 
3265 	for (i = 0; i < host->num_slots; i++) {
3266 		dev_dbg(host->dev, "remove slot %d\n", i);
3267 		if (host->slot[i])
3268 			dw_mci_cleanup_slot(host->slot[i], i);
3269 	}
3270 
3271 	mci_writel(host, RINTSTS, 0xFFFFFFFF);
3272 	mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */
3273 
3274 	/* disable clock to CIU */
3275 	mci_writel(host, CLKENA, 0);
3276 	mci_writel(host, CLKSRC, 0);
3277 
3278 	if (host->use_dma && host->dma_ops->exit)
3279 		host->dma_ops->exit(host);
3280 
3281 	if (!IS_ERR(host->pdata->rstc))
3282 		reset_control_assert(host->pdata->rstc);
3283 
3284 	clk_disable_unprepare(host->ciu_clk);
3285 	clk_disable_unprepare(host->biu_clk);
3286 }
3287 EXPORT_SYMBOL(dw_mci_remove);
3288 
3289 
3290 
3291 #ifdef CONFIG_PM
3292 int dw_mci_runtime_suspend(struct device *dev)
3293 {
3294 	struct dw_mci *host = dev_get_drvdata(dev);
3295 
3296 	if (host->use_dma && host->dma_ops->exit)
3297 		host->dma_ops->exit(host);
3298 
3299 	clk_disable_unprepare(host->ciu_clk);
3300 
3301 	if (host->cur_slot &&
3302 	    (mmc_can_gpio_cd(host->cur_slot->mmc) ||
3303 	     !mmc_card_is_removable(host->cur_slot->mmc)))
3304 		clk_disable_unprepare(host->biu_clk);
3305 
3306 	return 0;
3307 }
3308 EXPORT_SYMBOL(dw_mci_runtime_suspend);
3309 
3310 int dw_mci_runtime_resume(struct device *dev)
3311 {
3312 	int i, ret = 0;
3313 	struct dw_mci *host = dev_get_drvdata(dev);
3314 
3315 	if (host->cur_slot &&
3316 	    (mmc_can_gpio_cd(host->cur_slot->mmc) ||
3317 	     !mmc_card_is_removable(host->cur_slot->mmc))) {
3318 		ret = clk_prepare_enable(host->biu_clk);
3319 		if (ret)
3320 			return ret;
3321 	}
3322 
3323 	ret = clk_prepare_enable(host->ciu_clk);
3324 	if (ret)
3325 		goto err;
3326 
3327 	if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_ALL_RESET_FLAGS)) {
3328 		clk_disable_unprepare(host->ciu_clk);
3329 		ret = -ENODEV;
3330 		goto err;
3331 	}
3332 
3333 	if (host->use_dma && host->dma_ops->init)
3334 		host->dma_ops->init(host);
3335 
3336 	/*
3337 	 * Restore the initial value at FIFOTH register
3338 	 * And Invalidate the prev_blksz with zero
3339 	 */
3340 	 mci_writel(host, FIFOTH, host->fifoth_val);
3341 	 host->prev_blksz = 0;
3342 
3343 	/* Put in max timeout */
3344 	mci_writel(host, TMOUT, 0xFFFFFFFF);
3345 
3346 	mci_writel(host, RINTSTS, 0xFFFFFFFF);
3347 	mci_writel(host, INTMASK, SDMMC_INT_CMD_DONE | SDMMC_INT_DATA_OVER |
3348 		   SDMMC_INT_TXDR | SDMMC_INT_RXDR |
3349 		   DW_MCI_ERROR_FLAGS);
3350 	mci_writel(host, CTRL, SDMMC_CTRL_INT_ENABLE);
3351 
3352 	for (i = 0; i < host->num_slots; i++) {
3353 		struct dw_mci_slot *slot = host->slot[i];
3354 
3355 		if (!slot)
3356 			continue;
3357 		if (slot->mmc->pm_flags & MMC_PM_KEEP_POWER) {
3358 			dw_mci_set_ios(slot->mmc, &slot->mmc->ios);
3359 			dw_mci_setup_bus(slot, true);
3360 		}
3361 	}
3362 
3363 	/* Now that slots are all setup, we can enable card detect */
3364 	dw_mci_enable_cd(host);
3365 
3366 	return 0;
3367 
3368 err:
3369 	if (host->cur_slot &&
3370 	    (mmc_can_gpio_cd(host->cur_slot->mmc) ||
3371 	     !mmc_card_is_removable(host->cur_slot->mmc)))
3372 		clk_disable_unprepare(host->biu_clk);
3373 
3374 	return ret;
3375 }
3376 EXPORT_SYMBOL(dw_mci_runtime_resume);
3377 #endif /* CONFIG_PM */
3378 
3379 static int __init dw_mci_init(void)
3380 {
3381 	pr_info("Synopsys Designware Multimedia Card Interface Driver\n");
3382 	return 0;
3383 }
3384 
3385 static void __exit dw_mci_exit(void)
3386 {
3387 }
3388 
3389 module_init(dw_mci_init);
3390 module_exit(dw_mci_exit);
3391 
3392 MODULE_DESCRIPTION("DW Multimedia Card Interface driver");
3393 MODULE_AUTHOR("NXP Semiconductor VietNam");
3394 MODULE_AUTHOR("Imagination Technologies Ltd");
3395 MODULE_LICENSE("GPL v2");
3396