xref: /openbmc/linux/drivers/mmc/host/sdhci.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 /*
2  *  linux/drivers/mmc/host/sdhci.c - Secure Digital Host Controller Interface driver
3  *
4  *  Copyright (C) 2005-2008 Pierre Ossman, All Rights Reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or (at
9  * your option) any later version.
10  *
11  * Thanks to the following companies for their support:
12  *
13  *     - JMicron (hardware and technical support)
14  */
15 
16 #include <linux/delay.h>
17 #include <linux/highmem.h>
18 #include <linux/io.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/scatterlist.h>
21 
22 #include <linux/leds.h>
23 
24 #include <linux/mmc/host.h>
25 
26 #include "sdhci.h"
27 
28 #define DRIVER_NAME "sdhci"
29 
30 #define DBG(f, x...) \
31 	pr_debug(DRIVER_NAME " [%s()]: " f, __func__,## x)
32 
33 #if defined(CONFIG_LEDS_CLASS) || (defined(CONFIG_LEDS_CLASS_MODULE) && \
34 	defined(CONFIG_MMC_SDHCI_MODULE))
35 #define SDHCI_USE_LEDS_CLASS
36 #endif
37 
38 static unsigned int debug_quirks = 0;
39 
40 static void sdhci_prepare_data(struct sdhci_host *, struct mmc_data *);
41 static void sdhci_finish_data(struct sdhci_host *);
42 
43 static void sdhci_send_command(struct sdhci_host *, struct mmc_command *);
44 static void sdhci_finish_command(struct sdhci_host *);
45 
46 static void sdhci_dumpregs(struct sdhci_host *host)
47 {
48 	printk(KERN_DEBUG DRIVER_NAME ": ============== REGISTER DUMP ==============\n");
49 
50 	printk(KERN_DEBUG DRIVER_NAME ": Sys addr: 0x%08x | Version:  0x%08x\n",
51 		readl(host->ioaddr + SDHCI_DMA_ADDRESS),
52 		readw(host->ioaddr + SDHCI_HOST_VERSION));
53 	printk(KERN_DEBUG DRIVER_NAME ": Blk size: 0x%08x | Blk cnt:  0x%08x\n",
54 		readw(host->ioaddr + SDHCI_BLOCK_SIZE),
55 		readw(host->ioaddr + SDHCI_BLOCK_COUNT));
56 	printk(KERN_DEBUG DRIVER_NAME ": Argument: 0x%08x | Trn mode: 0x%08x\n",
57 		readl(host->ioaddr + SDHCI_ARGUMENT),
58 		readw(host->ioaddr + SDHCI_TRANSFER_MODE));
59 	printk(KERN_DEBUG DRIVER_NAME ": Present:  0x%08x | Host ctl: 0x%08x\n",
60 		readl(host->ioaddr + SDHCI_PRESENT_STATE),
61 		readb(host->ioaddr + SDHCI_HOST_CONTROL));
62 	printk(KERN_DEBUG DRIVER_NAME ": Power:    0x%08x | Blk gap:  0x%08x\n",
63 		readb(host->ioaddr + SDHCI_POWER_CONTROL),
64 		readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL));
65 	printk(KERN_DEBUG DRIVER_NAME ": Wake-up:  0x%08x | Clock:    0x%08x\n",
66 		readb(host->ioaddr + SDHCI_WAKE_UP_CONTROL),
67 		readw(host->ioaddr + SDHCI_CLOCK_CONTROL));
68 	printk(KERN_DEBUG DRIVER_NAME ": Timeout:  0x%08x | Int stat: 0x%08x\n",
69 		readb(host->ioaddr + SDHCI_TIMEOUT_CONTROL),
70 		readl(host->ioaddr + SDHCI_INT_STATUS));
71 	printk(KERN_DEBUG DRIVER_NAME ": Int enab: 0x%08x | Sig enab: 0x%08x\n",
72 		readl(host->ioaddr + SDHCI_INT_ENABLE),
73 		readl(host->ioaddr + SDHCI_SIGNAL_ENABLE));
74 	printk(KERN_DEBUG DRIVER_NAME ": AC12 err: 0x%08x | Slot int: 0x%08x\n",
75 		readw(host->ioaddr + SDHCI_ACMD12_ERR),
76 		readw(host->ioaddr + SDHCI_SLOT_INT_STATUS));
77 	printk(KERN_DEBUG DRIVER_NAME ": Caps:     0x%08x | Max curr: 0x%08x\n",
78 		readl(host->ioaddr + SDHCI_CAPABILITIES),
79 		readl(host->ioaddr + SDHCI_MAX_CURRENT));
80 
81 	printk(KERN_DEBUG DRIVER_NAME ": ===========================================\n");
82 }
83 
84 /*****************************************************************************\
85  *                                                                           *
86  * Low level functions                                                       *
87  *                                                                           *
88 \*****************************************************************************/
89 
90 static void sdhci_reset(struct sdhci_host *host, u8 mask)
91 {
92 	unsigned long timeout;
93 
94 	if (host->quirks & SDHCI_QUIRK_NO_CARD_NO_RESET) {
95 		if (!(readl(host->ioaddr + SDHCI_PRESENT_STATE) &
96 			SDHCI_CARD_PRESENT))
97 			return;
98 	}
99 
100 	writeb(mask, host->ioaddr + SDHCI_SOFTWARE_RESET);
101 
102 	if (mask & SDHCI_RESET_ALL)
103 		host->clock = 0;
104 
105 	/* Wait max 100 ms */
106 	timeout = 100;
107 
108 	/* hw clears the bit when it's done */
109 	while (readb(host->ioaddr + SDHCI_SOFTWARE_RESET) & mask) {
110 		if (timeout == 0) {
111 			printk(KERN_ERR "%s: Reset 0x%x never completed.\n",
112 				mmc_hostname(host->mmc), (int)mask);
113 			sdhci_dumpregs(host);
114 			return;
115 		}
116 		timeout--;
117 		mdelay(1);
118 	}
119 }
120 
121 static void sdhci_init(struct sdhci_host *host)
122 {
123 	u32 intmask;
124 
125 	sdhci_reset(host, SDHCI_RESET_ALL);
126 
127 	intmask = SDHCI_INT_BUS_POWER | SDHCI_INT_DATA_END_BIT |
128 		SDHCI_INT_DATA_CRC | SDHCI_INT_DATA_TIMEOUT | SDHCI_INT_INDEX |
129 		SDHCI_INT_END_BIT | SDHCI_INT_CRC | SDHCI_INT_TIMEOUT |
130 		SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT |
131 		SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL |
132 		SDHCI_INT_DMA_END | SDHCI_INT_DATA_END | SDHCI_INT_RESPONSE |
133 		SDHCI_INT_ADMA_ERROR;
134 
135 	writel(intmask, host->ioaddr + SDHCI_INT_ENABLE);
136 	writel(intmask, host->ioaddr + SDHCI_SIGNAL_ENABLE);
137 }
138 
139 static void sdhci_activate_led(struct sdhci_host *host)
140 {
141 	u8 ctrl;
142 
143 	ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
144 	ctrl |= SDHCI_CTRL_LED;
145 	writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
146 }
147 
148 static void sdhci_deactivate_led(struct sdhci_host *host)
149 {
150 	u8 ctrl;
151 
152 	ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
153 	ctrl &= ~SDHCI_CTRL_LED;
154 	writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
155 }
156 
157 #ifdef SDHCI_USE_LEDS_CLASS
158 static void sdhci_led_control(struct led_classdev *led,
159 	enum led_brightness brightness)
160 {
161 	struct sdhci_host *host = container_of(led, struct sdhci_host, led);
162 	unsigned long flags;
163 
164 	spin_lock_irqsave(&host->lock, flags);
165 
166 	if (brightness == LED_OFF)
167 		sdhci_deactivate_led(host);
168 	else
169 		sdhci_activate_led(host);
170 
171 	spin_unlock_irqrestore(&host->lock, flags);
172 }
173 #endif
174 
175 /*****************************************************************************\
176  *                                                                           *
177  * Core functions                                                            *
178  *                                                                           *
179 \*****************************************************************************/
180 
181 static void sdhci_read_block_pio(struct sdhci_host *host)
182 {
183 	unsigned long flags;
184 	size_t blksize, len, chunk;
185 	u32 uninitialized_var(scratch);
186 	u8 *buf;
187 
188 	DBG("PIO reading\n");
189 
190 	blksize = host->data->blksz;
191 	chunk = 0;
192 
193 	local_irq_save(flags);
194 
195 	while (blksize) {
196 		if (!sg_miter_next(&host->sg_miter))
197 			BUG();
198 
199 		len = min(host->sg_miter.length, blksize);
200 
201 		blksize -= len;
202 		host->sg_miter.consumed = len;
203 
204 		buf = host->sg_miter.addr;
205 
206 		while (len) {
207 			if (chunk == 0) {
208 				scratch = readl(host->ioaddr + SDHCI_BUFFER);
209 				chunk = 4;
210 			}
211 
212 			*buf = scratch & 0xFF;
213 
214 			buf++;
215 			scratch >>= 8;
216 			chunk--;
217 			len--;
218 		}
219 	}
220 
221 	sg_miter_stop(&host->sg_miter);
222 
223 	local_irq_restore(flags);
224 }
225 
226 static void sdhci_write_block_pio(struct sdhci_host *host)
227 {
228 	unsigned long flags;
229 	size_t blksize, len, chunk;
230 	u32 scratch;
231 	u8 *buf;
232 
233 	DBG("PIO writing\n");
234 
235 	blksize = host->data->blksz;
236 	chunk = 0;
237 	scratch = 0;
238 
239 	local_irq_save(flags);
240 
241 	while (blksize) {
242 		if (!sg_miter_next(&host->sg_miter))
243 			BUG();
244 
245 		len = min(host->sg_miter.length, blksize);
246 
247 		blksize -= len;
248 		host->sg_miter.consumed = len;
249 
250 		buf = host->sg_miter.addr;
251 
252 		while (len) {
253 			scratch |= (u32)*buf << (chunk * 8);
254 
255 			buf++;
256 			chunk++;
257 			len--;
258 
259 			if ((chunk == 4) || ((len == 0) && (blksize == 0))) {
260 				writel(scratch, host->ioaddr + SDHCI_BUFFER);
261 				chunk = 0;
262 				scratch = 0;
263 			}
264 		}
265 	}
266 
267 	sg_miter_stop(&host->sg_miter);
268 
269 	local_irq_restore(flags);
270 }
271 
272 static void sdhci_transfer_pio(struct sdhci_host *host)
273 {
274 	u32 mask;
275 
276 	BUG_ON(!host->data);
277 
278 	if (host->blocks == 0)
279 		return;
280 
281 	if (host->data->flags & MMC_DATA_READ)
282 		mask = SDHCI_DATA_AVAILABLE;
283 	else
284 		mask = SDHCI_SPACE_AVAILABLE;
285 
286 	/*
287 	 * Some controllers (JMicron JMB38x) mess up the buffer bits
288 	 * for transfers < 4 bytes. As long as it is just one block,
289 	 * we can ignore the bits.
290 	 */
291 	if ((host->quirks & SDHCI_QUIRK_BROKEN_SMALL_PIO) &&
292 		(host->data->blocks == 1))
293 		mask = ~0;
294 
295 	while (readl(host->ioaddr + SDHCI_PRESENT_STATE) & mask) {
296 		if (host->data->flags & MMC_DATA_READ)
297 			sdhci_read_block_pio(host);
298 		else
299 			sdhci_write_block_pio(host);
300 
301 		host->blocks--;
302 		if (host->blocks == 0)
303 			break;
304 	}
305 
306 	DBG("PIO transfer complete.\n");
307 }
308 
309 static char *sdhci_kmap_atomic(struct scatterlist *sg, unsigned long *flags)
310 {
311 	local_irq_save(*flags);
312 	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
313 }
314 
315 static void sdhci_kunmap_atomic(void *buffer, unsigned long *flags)
316 {
317 	kunmap_atomic(buffer, KM_BIO_SRC_IRQ);
318 	local_irq_restore(*flags);
319 }
320 
321 static int sdhci_adma_table_pre(struct sdhci_host *host,
322 	struct mmc_data *data)
323 {
324 	int direction;
325 
326 	u8 *desc;
327 	u8 *align;
328 	dma_addr_t addr;
329 	dma_addr_t align_addr;
330 	int len, offset;
331 
332 	struct scatterlist *sg;
333 	int i;
334 	char *buffer;
335 	unsigned long flags;
336 
337 	/*
338 	 * The spec does not specify endianness of descriptor table.
339 	 * We currently guess that it is LE.
340 	 */
341 
342 	if (data->flags & MMC_DATA_READ)
343 		direction = DMA_FROM_DEVICE;
344 	else
345 		direction = DMA_TO_DEVICE;
346 
347 	/*
348 	 * The ADMA descriptor table is mapped further down as we
349 	 * need to fill it with data first.
350 	 */
351 
352 	host->align_addr = dma_map_single(mmc_dev(host->mmc),
353 		host->align_buffer, 128 * 4, direction);
354 	if (dma_mapping_error(mmc_dev(host->mmc), host->align_addr))
355 		goto fail;
356 	BUG_ON(host->align_addr & 0x3);
357 
358 	host->sg_count = dma_map_sg(mmc_dev(host->mmc),
359 		data->sg, data->sg_len, direction);
360 	if (host->sg_count == 0)
361 		goto unmap_align;
362 
363 	desc = host->adma_desc;
364 	align = host->align_buffer;
365 
366 	align_addr = host->align_addr;
367 
368 	for_each_sg(data->sg, sg, host->sg_count, i) {
369 		addr = sg_dma_address(sg);
370 		len = sg_dma_len(sg);
371 
372 		/*
373 		 * The SDHCI specification states that ADMA
374 		 * addresses must be 32-bit aligned. If they
375 		 * aren't, then we use a bounce buffer for
376 		 * the (up to three) bytes that screw up the
377 		 * alignment.
378 		 */
379 		offset = (4 - (addr & 0x3)) & 0x3;
380 		if (offset) {
381 			if (data->flags & MMC_DATA_WRITE) {
382 				buffer = sdhci_kmap_atomic(sg, &flags);
383 				WARN_ON(((long)buffer & PAGE_MASK) > (PAGE_SIZE - 3));
384 				memcpy(align, buffer, offset);
385 				sdhci_kunmap_atomic(buffer, &flags);
386 			}
387 
388 			desc[7] = (align_addr >> 24) & 0xff;
389 			desc[6] = (align_addr >> 16) & 0xff;
390 			desc[5] = (align_addr >> 8) & 0xff;
391 			desc[4] = (align_addr >> 0) & 0xff;
392 
393 			BUG_ON(offset > 65536);
394 
395 			desc[3] = (offset >> 8) & 0xff;
396 			desc[2] = (offset >> 0) & 0xff;
397 
398 			desc[1] = 0x00;
399 			desc[0] = 0x21; /* tran, valid */
400 
401 			align += 4;
402 			align_addr += 4;
403 
404 			desc += 8;
405 
406 			addr += offset;
407 			len -= offset;
408 		}
409 
410 		desc[7] = (addr >> 24) & 0xff;
411 		desc[6] = (addr >> 16) & 0xff;
412 		desc[5] = (addr >> 8) & 0xff;
413 		desc[4] = (addr >> 0) & 0xff;
414 
415 		BUG_ON(len > 65536);
416 
417 		desc[3] = (len >> 8) & 0xff;
418 		desc[2] = (len >> 0) & 0xff;
419 
420 		desc[1] = 0x00;
421 		desc[0] = 0x21; /* tran, valid */
422 
423 		desc += 8;
424 
425 		/*
426 		 * If this triggers then we have a calculation bug
427 		 * somewhere. :/
428 		 */
429 		WARN_ON((desc - host->adma_desc) > (128 * 2 + 1) * 4);
430 	}
431 
432 	/*
433 	 * Add a terminating entry.
434 	 */
435 	desc[7] = 0;
436 	desc[6] = 0;
437 	desc[5] = 0;
438 	desc[4] = 0;
439 
440 	desc[3] = 0;
441 	desc[2] = 0;
442 
443 	desc[1] = 0x00;
444 	desc[0] = 0x03; /* nop, end, valid */
445 
446 	/*
447 	 * Resync align buffer as we might have changed it.
448 	 */
449 	if (data->flags & MMC_DATA_WRITE) {
450 		dma_sync_single_for_device(mmc_dev(host->mmc),
451 			host->align_addr, 128 * 4, direction);
452 	}
453 
454 	host->adma_addr = dma_map_single(mmc_dev(host->mmc),
455 		host->adma_desc, (128 * 2 + 1) * 4, DMA_TO_DEVICE);
456 	if (dma_mapping_error(mmc_dev(host->mmc), host->adma_addr))
457 		goto unmap_entries;
458 	BUG_ON(host->adma_addr & 0x3);
459 
460 	return 0;
461 
462 unmap_entries:
463 	dma_unmap_sg(mmc_dev(host->mmc), data->sg,
464 		data->sg_len, direction);
465 unmap_align:
466 	dma_unmap_single(mmc_dev(host->mmc), host->align_addr,
467 		128 * 4, direction);
468 fail:
469 	return -EINVAL;
470 }
471 
472 static void sdhci_adma_table_post(struct sdhci_host *host,
473 	struct mmc_data *data)
474 {
475 	int direction;
476 
477 	struct scatterlist *sg;
478 	int i, size;
479 	u8 *align;
480 	char *buffer;
481 	unsigned long flags;
482 
483 	if (data->flags & MMC_DATA_READ)
484 		direction = DMA_FROM_DEVICE;
485 	else
486 		direction = DMA_TO_DEVICE;
487 
488 	dma_unmap_single(mmc_dev(host->mmc), host->adma_addr,
489 		(128 * 2 + 1) * 4, DMA_TO_DEVICE);
490 
491 	dma_unmap_single(mmc_dev(host->mmc), host->align_addr,
492 		128 * 4, direction);
493 
494 	if (data->flags & MMC_DATA_READ) {
495 		dma_sync_sg_for_cpu(mmc_dev(host->mmc), data->sg,
496 			data->sg_len, direction);
497 
498 		align = host->align_buffer;
499 
500 		for_each_sg(data->sg, sg, host->sg_count, i) {
501 			if (sg_dma_address(sg) & 0x3) {
502 				size = 4 - (sg_dma_address(sg) & 0x3);
503 
504 				buffer = sdhci_kmap_atomic(sg, &flags);
505 				WARN_ON(((long)buffer & PAGE_MASK) > (PAGE_SIZE - 3));
506 				memcpy(buffer, align, size);
507 				sdhci_kunmap_atomic(buffer, &flags);
508 
509 				align += 4;
510 			}
511 		}
512 	}
513 
514 	dma_unmap_sg(mmc_dev(host->mmc), data->sg,
515 		data->sg_len, direction);
516 }
517 
518 static u8 sdhci_calc_timeout(struct sdhci_host *host, struct mmc_data *data)
519 {
520 	u8 count;
521 	unsigned target_timeout, current_timeout;
522 
523 	/*
524 	 * If the host controller provides us with an incorrect timeout
525 	 * value, just skip the check and use 0xE.  The hardware may take
526 	 * longer to time out, but that's much better than having a too-short
527 	 * timeout value.
528 	 */
529 	if ((host->quirks & SDHCI_QUIRK_BROKEN_TIMEOUT_VAL))
530 		return 0xE;
531 
532 	/* timeout in us */
533 	target_timeout = data->timeout_ns / 1000 +
534 		data->timeout_clks / host->clock;
535 
536 	/*
537 	 * Figure out needed cycles.
538 	 * We do this in steps in order to fit inside a 32 bit int.
539 	 * The first step is the minimum timeout, which will have a
540 	 * minimum resolution of 6 bits:
541 	 * (1) 2^13*1000 > 2^22,
542 	 * (2) host->timeout_clk < 2^16
543 	 *     =>
544 	 *     (1) / (2) > 2^6
545 	 */
546 	count = 0;
547 	current_timeout = (1 << 13) * 1000 / host->timeout_clk;
548 	while (current_timeout < target_timeout) {
549 		count++;
550 		current_timeout <<= 1;
551 		if (count >= 0xF)
552 			break;
553 	}
554 
555 	if (count >= 0xF) {
556 		printk(KERN_WARNING "%s: Too large timeout requested!\n",
557 			mmc_hostname(host->mmc));
558 		count = 0xE;
559 	}
560 
561 	return count;
562 }
563 
564 static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data)
565 {
566 	u8 count;
567 	u8 ctrl;
568 	int ret;
569 
570 	WARN_ON(host->data);
571 
572 	if (data == NULL)
573 		return;
574 
575 	/* Sanity checks */
576 	BUG_ON(data->blksz * data->blocks > 524288);
577 	BUG_ON(data->blksz > host->mmc->max_blk_size);
578 	BUG_ON(data->blocks > 65535);
579 
580 	host->data = data;
581 	host->data_early = 0;
582 
583 	count = sdhci_calc_timeout(host, data);
584 	writeb(count, host->ioaddr + SDHCI_TIMEOUT_CONTROL);
585 
586 	if (host->flags & SDHCI_USE_DMA)
587 		host->flags |= SDHCI_REQ_USE_DMA;
588 
589 	/*
590 	 * FIXME: This doesn't account for merging when mapping the
591 	 * scatterlist.
592 	 */
593 	if (host->flags & SDHCI_REQ_USE_DMA) {
594 		int broken, i;
595 		struct scatterlist *sg;
596 
597 		broken = 0;
598 		if (host->flags & SDHCI_USE_ADMA) {
599 			if (host->quirks & SDHCI_QUIRK_32BIT_ADMA_SIZE)
600 				broken = 1;
601 		} else {
602 			if (host->quirks & SDHCI_QUIRK_32BIT_DMA_SIZE)
603 				broken = 1;
604 		}
605 
606 		if (unlikely(broken)) {
607 			for_each_sg(data->sg, sg, data->sg_len, i) {
608 				if (sg->length & 0x3) {
609 					DBG("Reverting to PIO because of "
610 						"transfer size (%d)\n",
611 						sg->length);
612 					host->flags &= ~SDHCI_REQ_USE_DMA;
613 					break;
614 				}
615 			}
616 		}
617 	}
618 
619 	/*
620 	 * The assumption here being that alignment is the same after
621 	 * translation to device address space.
622 	 */
623 	if (host->flags & SDHCI_REQ_USE_DMA) {
624 		int broken, i;
625 		struct scatterlist *sg;
626 
627 		broken = 0;
628 		if (host->flags & SDHCI_USE_ADMA) {
629 			/*
630 			 * As we use 3 byte chunks to work around
631 			 * alignment problems, we need to check this
632 			 * quirk.
633 			 */
634 			if (host->quirks & SDHCI_QUIRK_32BIT_ADMA_SIZE)
635 				broken = 1;
636 		} else {
637 			if (host->quirks & SDHCI_QUIRK_32BIT_DMA_ADDR)
638 				broken = 1;
639 		}
640 
641 		if (unlikely(broken)) {
642 			for_each_sg(data->sg, sg, data->sg_len, i) {
643 				if (sg->offset & 0x3) {
644 					DBG("Reverting to PIO because of "
645 						"bad alignment\n");
646 					host->flags &= ~SDHCI_REQ_USE_DMA;
647 					break;
648 				}
649 			}
650 		}
651 	}
652 
653 	if (host->flags & SDHCI_REQ_USE_DMA) {
654 		if (host->flags & SDHCI_USE_ADMA) {
655 			ret = sdhci_adma_table_pre(host, data);
656 			if (ret) {
657 				/*
658 				 * This only happens when someone fed
659 				 * us an invalid request.
660 				 */
661 				WARN_ON(1);
662 				host->flags &= ~SDHCI_REQ_USE_DMA;
663 			} else {
664 				writel(host->adma_addr,
665 					host->ioaddr + SDHCI_ADMA_ADDRESS);
666 			}
667 		} else {
668 			int sg_cnt;
669 
670 			sg_cnt = dma_map_sg(mmc_dev(host->mmc),
671 					data->sg, data->sg_len,
672 					(data->flags & MMC_DATA_READ) ?
673 						DMA_FROM_DEVICE :
674 						DMA_TO_DEVICE);
675 			if (sg_cnt == 0) {
676 				/*
677 				 * This only happens when someone fed
678 				 * us an invalid request.
679 				 */
680 				WARN_ON(1);
681 				host->flags &= ~SDHCI_REQ_USE_DMA;
682 			} else {
683 				WARN_ON(sg_cnt != 1);
684 				writel(sg_dma_address(data->sg),
685 					host->ioaddr + SDHCI_DMA_ADDRESS);
686 			}
687 		}
688 	}
689 
690 	/*
691 	 * Always adjust the DMA selection as some controllers
692 	 * (e.g. JMicron) can't do PIO properly when the selection
693 	 * is ADMA.
694 	 */
695 	if (host->version >= SDHCI_SPEC_200) {
696 		ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
697 		ctrl &= ~SDHCI_CTRL_DMA_MASK;
698 		if ((host->flags & SDHCI_REQ_USE_DMA) &&
699 			(host->flags & SDHCI_USE_ADMA))
700 			ctrl |= SDHCI_CTRL_ADMA32;
701 		else
702 			ctrl |= SDHCI_CTRL_SDMA;
703 		writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
704 	}
705 
706 	if (!(host->flags & SDHCI_REQ_USE_DMA)) {
707 		sg_miter_start(&host->sg_miter,
708 			data->sg, data->sg_len, SG_MITER_ATOMIC);
709 		host->blocks = data->blocks;
710 	}
711 
712 	/* We do not handle DMA boundaries, so set it to max (512 KiB) */
713 	writew(SDHCI_MAKE_BLKSZ(7, data->blksz),
714 		host->ioaddr + SDHCI_BLOCK_SIZE);
715 	writew(data->blocks, host->ioaddr + SDHCI_BLOCK_COUNT);
716 }
717 
718 static void sdhci_set_transfer_mode(struct sdhci_host *host,
719 	struct mmc_data *data)
720 {
721 	u16 mode;
722 
723 	if (data == NULL)
724 		return;
725 
726 	WARN_ON(!host->data);
727 
728 	mode = SDHCI_TRNS_BLK_CNT_EN;
729 	if (data->blocks > 1)
730 		mode |= SDHCI_TRNS_MULTI;
731 	if (data->flags & MMC_DATA_READ)
732 		mode |= SDHCI_TRNS_READ;
733 	if (host->flags & SDHCI_REQ_USE_DMA)
734 		mode |= SDHCI_TRNS_DMA;
735 
736 	writew(mode, host->ioaddr + SDHCI_TRANSFER_MODE);
737 }
738 
739 static void sdhci_finish_data(struct sdhci_host *host)
740 {
741 	struct mmc_data *data;
742 
743 	BUG_ON(!host->data);
744 
745 	data = host->data;
746 	host->data = NULL;
747 
748 	if (host->flags & SDHCI_REQ_USE_DMA) {
749 		if (host->flags & SDHCI_USE_ADMA)
750 			sdhci_adma_table_post(host, data);
751 		else {
752 			dma_unmap_sg(mmc_dev(host->mmc), data->sg,
753 				data->sg_len, (data->flags & MMC_DATA_READ) ?
754 					DMA_FROM_DEVICE : DMA_TO_DEVICE);
755 		}
756 	}
757 
758 	/*
759 	 * The specification states that the block count register must
760 	 * be updated, but it does not specify at what point in the
761 	 * data flow. That makes the register entirely useless to read
762 	 * back so we have to assume that nothing made it to the card
763 	 * in the event of an error.
764 	 */
765 	if (data->error)
766 		data->bytes_xfered = 0;
767 	else
768 		data->bytes_xfered = data->blksz * data->blocks;
769 
770 	if (data->stop) {
771 		/*
772 		 * The controller needs a reset of internal state machines
773 		 * upon error conditions.
774 		 */
775 		if (data->error) {
776 			sdhci_reset(host, SDHCI_RESET_CMD);
777 			sdhci_reset(host, SDHCI_RESET_DATA);
778 		}
779 
780 		sdhci_send_command(host, data->stop);
781 	} else
782 		tasklet_schedule(&host->finish_tasklet);
783 }
784 
785 static void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd)
786 {
787 	int flags;
788 	u32 mask;
789 	unsigned long timeout;
790 
791 	WARN_ON(host->cmd);
792 
793 	/* Wait max 10 ms */
794 	timeout = 10;
795 
796 	mask = SDHCI_CMD_INHIBIT;
797 	if ((cmd->data != NULL) || (cmd->flags & MMC_RSP_BUSY))
798 		mask |= SDHCI_DATA_INHIBIT;
799 
800 	/* We shouldn't wait for data inihibit for stop commands, even
801 	   though they might use busy signaling */
802 	if (host->mrq->data && (cmd == host->mrq->data->stop))
803 		mask &= ~SDHCI_DATA_INHIBIT;
804 
805 	while (readl(host->ioaddr + SDHCI_PRESENT_STATE) & mask) {
806 		if (timeout == 0) {
807 			printk(KERN_ERR "%s: Controller never released "
808 				"inhibit bit(s).\n", mmc_hostname(host->mmc));
809 			sdhci_dumpregs(host);
810 			cmd->error = -EIO;
811 			tasklet_schedule(&host->finish_tasklet);
812 			return;
813 		}
814 		timeout--;
815 		mdelay(1);
816 	}
817 
818 	mod_timer(&host->timer, jiffies + 10 * HZ);
819 
820 	host->cmd = cmd;
821 
822 	sdhci_prepare_data(host, cmd->data);
823 
824 	writel(cmd->arg, host->ioaddr + SDHCI_ARGUMENT);
825 
826 	sdhci_set_transfer_mode(host, cmd->data);
827 
828 	if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
829 		printk(KERN_ERR "%s: Unsupported response type!\n",
830 			mmc_hostname(host->mmc));
831 		cmd->error = -EINVAL;
832 		tasklet_schedule(&host->finish_tasklet);
833 		return;
834 	}
835 
836 	if (!(cmd->flags & MMC_RSP_PRESENT))
837 		flags = SDHCI_CMD_RESP_NONE;
838 	else if (cmd->flags & MMC_RSP_136)
839 		flags = SDHCI_CMD_RESP_LONG;
840 	else if (cmd->flags & MMC_RSP_BUSY)
841 		flags = SDHCI_CMD_RESP_SHORT_BUSY;
842 	else
843 		flags = SDHCI_CMD_RESP_SHORT;
844 
845 	if (cmd->flags & MMC_RSP_CRC)
846 		flags |= SDHCI_CMD_CRC;
847 	if (cmd->flags & MMC_RSP_OPCODE)
848 		flags |= SDHCI_CMD_INDEX;
849 	if (cmd->data)
850 		flags |= SDHCI_CMD_DATA;
851 
852 	writew(SDHCI_MAKE_CMD(cmd->opcode, flags),
853 		host->ioaddr + SDHCI_COMMAND);
854 }
855 
856 static void sdhci_finish_command(struct sdhci_host *host)
857 {
858 	int i;
859 
860 	BUG_ON(host->cmd == NULL);
861 
862 	if (host->cmd->flags & MMC_RSP_PRESENT) {
863 		if (host->cmd->flags & MMC_RSP_136) {
864 			/* CRC is stripped so we need to do some shifting. */
865 			for (i = 0;i < 4;i++) {
866 				host->cmd->resp[i] = readl(host->ioaddr +
867 					SDHCI_RESPONSE + (3-i)*4) << 8;
868 				if (i != 3)
869 					host->cmd->resp[i] |=
870 						readb(host->ioaddr +
871 						SDHCI_RESPONSE + (3-i)*4-1);
872 			}
873 		} else {
874 			host->cmd->resp[0] = readl(host->ioaddr + SDHCI_RESPONSE);
875 		}
876 	}
877 
878 	host->cmd->error = 0;
879 
880 	if (host->data && host->data_early)
881 		sdhci_finish_data(host);
882 
883 	if (!host->cmd->data)
884 		tasklet_schedule(&host->finish_tasklet);
885 
886 	host->cmd = NULL;
887 }
888 
889 static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
890 {
891 	int div;
892 	u16 clk;
893 	unsigned long timeout;
894 
895 	if (clock == host->clock)
896 		return;
897 
898 	writew(0, host->ioaddr + SDHCI_CLOCK_CONTROL);
899 
900 	if (clock == 0)
901 		goto out;
902 
903 	for (div = 1;div < 256;div *= 2) {
904 		if ((host->max_clk / div) <= clock)
905 			break;
906 	}
907 	div >>= 1;
908 
909 	clk = div << SDHCI_DIVIDER_SHIFT;
910 	clk |= SDHCI_CLOCK_INT_EN;
911 	writew(clk, host->ioaddr + SDHCI_CLOCK_CONTROL);
912 
913 	/* Wait max 10 ms */
914 	timeout = 10;
915 	while (!((clk = readw(host->ioaddr + SDHCI_CLOCK_CONTROL))
916 		& SDHCI_CLOCK_INT_STABLE)) {
917 		if (timeout == 0) {
918 			printk(KERN_ERR "%s: Internal clock never "
919 				"stabilised.\n", mmc_hostname(host->mmc));
920 			sdhci_dumpregs(host);
921 			return;
922 		}
923 		timeout--;
924 		mdelay(1);
925 	}
926 
927 	clk |= SDHCI_CLOCK_CARD_EN;
928 	writew(clk, host->ioaddr + SDHCI_CLOCK_CONTROL);
929 
930 out:
931 	host->clock = clock;
932 }
933 
934 static void sdhci_set_power(struct sdhci_host *host, unsigned short power)
935 {
936 	u8 pwr;
937 
938 	if (host->power == power)
939 		return;
940 
941 	if (power == (unsigned short)-1) {
942 		writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);
943 		goto out;
944 	}
945 
946 	/*
947 	 * Spec says that we should clear the power reg before setting
948 	 * a new value. Some controllers don't seem to like this though.
949 	 */
950 	if (!(host->quirks & SDHCI_QUIRK_SINGLE_POWER_WRITE))
951 		writeb(0, host->ioaddr + SDHCI_POWER_CONTROL);
952 
953 	pwr = SDHCI_POWER_ON;
954 
955 	switch (1 << power) {
956 	case MMC_VDD_165_195:
957 		pwr |= SDHCI_POWER_180;
958 		break;
959 	case MMC_VDD_29_30:
960 	case MMC_VDD_30_31:
961 		pwr |= SDHCI_POWER_300;
962 		break;
963 	case MMC_VDD_32_33:
964 	case MMC_VDD_33_34:
965 		pwr |= SDHCI_POWER_330;
966 		break;
967 	default:
968 		BUG();
969 	}
970 
971 	/*
972 	 * At least the Marvell CaFe chip gets confused if we set the voltage
973 	 * and set turn on power at the same time, so set the voltage first.
974 	 */
975 	if ((host->quirks & SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER))
976 		writeb(pwr & ~SDHCI_POWER_ON,
977 				host->ioaddr + SDHCI_POWER_CONTROL);
978 
979 	writeb(pwr, host->ioaddr + SDHCI_POWER_CONTROL);
980 
981 out:
982 	host->power = power;
983 }
984 
985 /*****************************************************************************\
986  *                                                                           *
987  * MMC callbacks                                                             *
988  *                                                                           *
989 \*****************************************************************************/
990 
991 static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
992 {
993 	struct sdhci_host *host;
994 	unsigned long flags;
995 
996 	host = mmc_priv(mmc);
997 
998 	spin_lock_irqsave(&host->lock, flags);
999 
1000 	WARN_ON(host->mrq != NULL);
1001 
1002 #ifndef SDHCI_USE_LEDS_CLASS
1003 	sdhci_activate_led(host);
1004 #endif
1005 
1006 	host->mrq = mrq;
1007 
1008 	if (!(readl(host->ioaddr + SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT)
1009 		|| (host->flags & SDHCI_DEVICE_DEAD)) {
1010 		host->mrq->cmd->error = -ENOMEDIUM;
1011 		tasklet_schedule(&host->finish_tasklet);
1012 	} else
1013 		sdhci_send_command(host, mrq->cmd);
1014 
1015 	mmiowb();
1016 	spin_unlock_irqrestore(&host->lock, flags);
1017 }
1018 
1019 static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1020 {
1021 	struct sdhci_host *host;
1022 	unsigned long flags;
1023 	u8 ctrl;
1024 
1025 	host = mmc_priv(mmc);
1026 
1027 	spin_lock_irqsave(&host->lock, flags);
1028 
1029 	if (host->flags & SDHCI_DEVICE_DEAD)
1030 		goto out;
1031 
1032 	/*
1033 	 * Reset the chip on each power off.
1034 	 * Should clear out any weird states.
1035 	 */
1036 	if (ios->power_mode == MMC_POWER_OFF) {
1037 		writel(0, host->ioaddr + SDHCI_SIGNAL_ENABLE);
1038 		sdhci_init(host);
1039 	}
1040 
1041 	sdhci_set_clock(host, ios->clock);
1042 
1043 	if (ios->power_mode == MMC_POWER_OFF)
1044 		sdhci_set_power(host, -1);
1045 	else
1046 		sdhci_set_power(host, ios->vdd);
1047 
1048 	ctrl = readb(host->ioaddr + SDHCI_HOST_CONTROL);
1049 
1050 	if (ios->bus_width == MMC_BUS_WIDTH_4)
1051 		ctrl |= SDHCI_CTRL_4BITBUS;
1052 	else
1053 		ctrl &= ~SDHCI_CTRL_4BITBUS;
1054 
1055 	if (ios->timing == MMC_TIMING_SD_HS)
1056 		ctrl |= SDHCI_CTRL_HISPD;
1057 	else
1058 		ctrl &= ~SDHCI_CTRL_HISPD;
1059 
1060 	writeb(ctrl, host->ioaddr + SDHCI_HOST_CONTROL);
1061 
1062 	/*
1063 	 * Some (ENE) controllers go apeshit on some ios operation,
1064 	 * signalling timeout and CRC errors even on CMD0. Resetting
1065 	 * it on each ios seems to solve the problem.
1066 	 */
1067 	if(host->quirks & SDHCI_QUIRK_RESET_CMD_DATA_ON_IOS)
1068 		sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
1069 
1070 out:
1071 	mmiowb();
1072 	spin_unlock_irqrestore(&host->lock, flags);
1073 }
1074 
1075 static int sdhci_get_ro(struct mmc_host *mmc)
1076 {
1077 	struct sdhci_host *host;
1078 	unsigned long flags;
1079 	int present;
1080 
1081 	host = mmc_priv(mmc);
1082 
1083 	spin_lock_irqsave(&host->lock, flags);
1084 
1085 	if (host->flags & SDHCI_DEVICE_DEAD)
1086 		present = 0;
1087 	else
1088 		present = readl(host->ioaddr + SDHCI_PRESENT_STATE);
1089 
1090 	spin_unlock_irqrestore(&host->lock, flags);
1091 
1092 	return !(present & SDHCI_WRITE_PROTECT);
1093 }
1094 
1095 static void sdhci_enable_sdio_irq(struct mmc_host *mmc, int enable)
1096 {
1097 	struct sdhci_host *host;
1098 	unsigned long flags;
1099 	u32 ier;
1100 
1101 	host = mmc_priv(mmc);
1102 
1103 	spin_lock_irqsave(&host->lock, flags);
1104 
1105 	if (host->flags & SDHCI_DEVICE_DEAD)
1106 		goto out;
1107 
1108 	ier = readl(host->ioaddr + SDHCI_INT_ENABLE);
1109 
1110 	ier &= ~SDHCI_INT_CARD_INT;
1111 	if (enable)
1112 		ier |= SDHCI_INT_CARD_INT;
1113 
1114 	writel(ier, host->ioaddr + SDHCI_INT_ENABLE);
1115 	writel(ier, host->ioaddr + SDHCI_SIGNAL_ENABLE);
1116 
1117 out:
1118 	mmiowb();
1119 
1120 	spin_unlock_irqrestore(&host->lock, flags);
1121 }
1122 
1123 static const struct mmc_host_ops sdhci_ops = {
1124 	.request	= sdhci_request,
1125 	.set_ios	= sdhci_set_ios,
1126 	.get_ro		= sdhci_get_ro,
1127 	.enable_sdio_irq = sdhci_enable_sdio_irq,
1128 };
1129 
1130 /*****************************************************************************\
1131  *                                                                           *
1132  * Tasklets                                                                  *
1133  *                                                                           *
1134 \*****************************************************************************/
1135 
1136 static void sdhci_tasklet_card(unsigned long param)
1137 {
1138 	struct sdhci_host *host;
1139 	unsigned long flags;
1140 
1141 	host = (struct sdhci_host*)param;
1142 
1143 	spin_lock_irqsave(&host->lock, flags);
1144 
1145 	if (!(readl(host->ioaddr + SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT)) {
1146 		if (host->mrq) {
1147 			printk(KERN_ERR "%s: Card removed during transfer!\n",
1148 				mmc_hostname(host->mmc));
1149 			printk(KERN_ERR "%s: Resetting controller.\n",
1150 				mmc_hostname(host->mmc));
1151 
1152 			sdhci_reset(host, SDHCI_RESET_CMD);
1153 			sdhci_reset(host, SDHCI_RESET_DATA);
1154 
1155 			host->mrq->cmd->error = -ENOMEDIUM;
1156 			tasklet_schedule(&host->finish_tasklet);
1157 		}
1158 	}
1159 
1160 	spin_unlock_irqrestore(&host->lock, flags);
1161 
1162 	mmc_detect_change(host->mmc, msecs_to_jiffies(200));
1163 }
1164 
1165 static void sdhci_tasklet_finish(unsigned long param)
1166 {
1167 	struct sdhci_host *host;
1168 	unsigned long flags;
1169 	struct mmc_request *mrq;
1170 
1171 	host = (struct sdhci_host*)param;
1172 
1173 	spin_lock_irqsave(&host->lock, flags);
1174 
1175 	del_timer(&host->timer);
1176 
1177 	mrq = host->mrq;
1178 
1179 	/*
1180 	 * The controller needs a reset of internal state machines
1181 	 * upon error conditions.
1182 	 */
1183 	if (!(host->flags & SDHCI_DEVICE_DEAD) &&
1184 		(mrq->cmd->error ||
1185 		 (mrq->data && (mrq->data->error ||
1186 		  (mrq->data->stop && mrq->data->stop->error))) ||
1187 		   (host->quirks & SDHCI_QUIRK_RESET_AFTER_REQUEST))) {
1188 
1189 		/* Some controllers need this kick or reset won't work here */
1190 		if (host->quirks & SDHCI_QUIRK_CLOCK_BEFORE_RESET) {
1191 			unsigned int clock;
1192 
1193 			/* This is to force an update */
1194 			clock = host->clock;
1195 			host->clock = 0;
1196 			sdhci_set_clock(host, clock);
1197 		}
1198 
1199 		/* Spec says we should do both at the same time, but Ricoh
1200 		   controllers do not like that. */
1201 		sdhci_reset(host, SDHCI_RESET_CMD);
1202 		sdhci_reset(host, SDHCI_RESET_DATA);
1203 	}
1204 
1205 	host->mrq = NULL;
1206 	host->cmd = NULL;
1207 	host->data = NULL;
1208 
1209 #ifndef SDHCI_USE_LEDS_CLASS
1210 	sdhci_deactivate_led(host);
1211 #endif
1212 
1213 	mmiowb();
1214 	spin_unlock_irqrestore(&host->lock, flags);
1215 
1216 	mmc_request_done(host->mmc, mrq);
1217 }
1218 
1219 static void sdhci_timeout_timer(unsigned long data)
1220 {
1221 	struct sdhci_host *host;
1222 	unsigned long flags;
1223 
1224 	host = (struct sdhci_host*)data;
1225 
1226 	spin_lock_irqsave(&host->lock, flags);
1227 
1228 	if (host->mrq) {
1229 		printk(KERN_ERR "%s: Timeout waiting for hardware "
1230 			"interrupt.\n", mmc_hostname(host->mmc));
1231 		sdhci_dumpregs(host);
1232 
1233 		if (host->data) {
1234 			host->data->error = -ETIMEDOUT;
1235 			sdhci_finish_data(host);
1236 		} else {
1237 			if (host->cmd)
1238 				host->cmd->error = -ETIMEDOUT;
1239 			else
1240 				host->mrq->cmd->error = -ETIMEDOUT;
1241 
1242 			tasklet_schedule(&host->finish_tasklet);
1243 		}
1244 	}
1245 
1246 	mmiowb();
1247 	spin_unlock_irqrestore(&host->lock, flags);
1248 }
1249 
1250 /*****************************************************************************\
1251  *                                                                           *
1252  * Interrupt handling                                                        *
1253  *                                                                           *
1254 \*****************************************************************************/
1255 
1256 static void sdhci_cmd_irq(struct sdhci_host *host, u32 intmask)
1257 {
1258 	BUG_ON(intmask == 0);
1259 
1260 	if (!host->cmd) {
1261 		printk(KERN_ERR "%s: Got command interrupt 0x%08x even "
1262 			"though no command operation was in progress.\n",
1263 			mmc_hostname(host->mmc), (unsigned)intmask);
1264 		sdhci_dumpregs(host);
1265 		return;
1266 	}
1267 
1268 	if (intmask & SDHCI_INT_TIMEOUT)
1269 		host->cmd->error = -ETIMEDOUT;
1270 	else if (intmask & (SDHCI_INT_CRC | SDHCI_INT_END_BIT |
1271 			SDHCI_INT_INDEX))
1272 		host->cmd->error = -EILSEQ;
1273 
1274 	if (host->cmd->error) {
1275 		tasklet_schedule(&host->finish_tasklet);
1276 		return;
1277 	}
1278 
1279 	/*
1280 	 * The host can send and interrupt when the busy state has
1281 	 * ended, allowing us to wait without wasting CPU cycles.
1282 	 * Unfortunately this is overloaded on the "data complete"
1283 	 * interrupt, so we need to take some care when handling
1284 	 * it.
1285 	 *
1286 	 * Note: The 1.0 specification is a bit ambiguous about this
1287 	 *       feature so there might be some problems with older
1288 	 *       controllers.
1289 	 */
1290 	if (host->cmd->flags & MMC_RSP_BUSY) {
1291 		if (host->cmd->data)
1292 			DBG("Cannot wait for busy signal when also "
1293 				"doing a data transfer");
1294 		else if (!(host->quirks & SDHCI_QUIRK_NO_BUSY_IRQ))
1295 			return;
1296 
1297 		/* The controller does not support the end-of-busy IRQ,
1298 		 * fall through and take the SDHCI_INT_RESPONSE */
1299 	}
1300 
1301 	if (intmask & SDHCI_INT_RESPONSE)
1302 		sdhci_finish_command(host);
1303 }
1304 
1305 static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
1306 {
1307 	BUG_ON(intmask == 0);
1308 
1309 	if (!host->data) {
1310 		/*
1311 		 * The "data complete" interrupt is also used to
1312 		 * indicate that a busy state has ended. See comment
1313 		 * above in sdhci_cmd_irq().
1314 		 */
1315 		if (host->cmd && (host->cmd->flags & MMC_RSP_BUSY)) {
1316 			if (intmask & SDHCI_INT_DATA_END) {
1317 				sdhci_finish_command(host);
1318 				return;
1319 			}
1320 		}
1321 
1322 		printk(KERN_ERR "%s: Got data interrupt 0x%08x even "
1323 			"though no data operation was in progress.\n",
1324 			mmc_hostname(host->mmc), (unsigned)intmask);
1325 		sdhci_dumpregs(host);
1326 
1327 		return;
1328 	}
1329 
1330 	if (intmask & SDHCI_INT_DATA_TIMEOUT)
1331 		host->data->error = -ETIMEDOUT;
1332 	else if (intmask & (SDHCI_INT_DATA_CRC | SDHCI_INT_DATA_END_BIT))
1333 		host->data->error = -EILSEQ;
1334 	else if (intmask & SDHCI_INT_ADMA_ERROR)
1335 		host->data->error = -EIO;
1336 
1337 	if (host->data->error)
1338 		sdhci_finish_data(host);
1339 	else {
1340 		if (intmask & (SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL))
1341 			sdhci_transfer_pio(host);
1342 
1343 		/*
1344 		 * We currently don't do anything fancy with DMA
1345 		 * boundaries, but as we can't disable the feature
1346 		 * we need to at least restart the transfer.
1347 		 */
1348 		if (intmask & SDHCI_INT_DMA_END)
1349 			writel(readl(host->ioaddr + SDHCI_DMA_ADDRESS),
1350 				host->ioaddr + SDHCI_DMA_ADDRESS);
1351 
1352 		if (intmask & SDHCI_INT_DATA_END) {
1353 			if (host->cmd) {
1354 				/*
1355 				 * Data managed to finish before the
1356 				 * command completed. Make sure we do
1357 				 * things in the proper order.
1358 				 */
1359 				host->data_early = 1;
1360 			} else {
1361 				sdhci_finish_data(host);
1362 			}
1363 		}
1364 	}
1365 }
1366 
1367 static irqreturn_t sdhci_irq(int irq, void *dev_id)
1368 {
1369 	irqreturn_t result;
1370 	struct sdhci_host* host = dev_id;
1371 	u32 intmask;
1372 	int cardint = 0;
1373 
1374 	spin_lock(&host->lock);
1375 
1376 	intmask = readl(host->ioaddr + SDHCI_INT_STATUS);
1377 
1378 	if (!intmask || intmask == 0xffffffff) {
1379 		result = IRQ_NONE;
1380 		goto out;
1381 	}
1382 
1383 	DBG("*** %s got interrupt: 0x%08x\n",
1384 		mmc_hostname(host->mmc), intmask);
1385 
1386 	if (intmask & (SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE)) {
1387 		writel(intmask & (SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE),
1388 			host->ioaddr + SDHCI_INT_STATUS);
1389 		tasklet_schedule(&host->card_tasklet);
1390 	}
1391 
1392 	intmask &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE);
1393 
1394 	if (intmask & SDHCI_INT_CMD_MASK) {
1395 		writel(intmask & SDHCI_INT_CMD_MASK,
1396 			host->ioaddr + SDHCI_INT_STATUS);
1397 		sdhci_cmd_irq(host, intmask & SDHCI_INT_CMD_MASK);
1398 	}
1399 
1400 	if (intmask & SDHCI_INT_DATA_MASK) {
1401 		writel(intmask & SDHCI_INT_DATA_MASK,
1402 			host->ioaddr + SDHCI_INT_STATUS);
1403 		sdhci_data_irq(host, intmask & SDHCI_INT_DATA_MASK);
1404 	}
1405 
1406 	intmask &= ~(SDHCI_INT_CMD_MASK | SDHCI_INT_DATA_MASK);
1407 
1408 	intmask &= ~SDHCI_INT_ERROR;
1409 
1410 	if (intmask & SDHCI_INT_BUS_POWER) {
1411 		printk(KERN_ERR "%s: Card is consuming too much power!\n",
1412 			mmc_hostname(host->mmc));
1413 		writel(SDHCI_INT_BUS_POWER, host->ioaddr + SDHCI_INT_STATUS);
1414 	}
1415 
1416 	intmask &= ~SDHCI_INT_BUS_POWER;
1417 
1418 	if (intmask & SDHCI_INT_CARD_INT)
1419 		cardint = 1;
1420 
1421 	intmask &= ~SDHCI_INT_CARD_INT;
1422 
1423 	if (intmask) {
1424 		printk(KERN_ERR "%s: Unexpected interrupt 0x%08x.\n",
1425 			mmc_hostname(host->mmc), intmask);
1426 		sdhci_dumpregs(host);
1427 
1428 		writel(intmask, host->ioaddr + SDHCI_INT_STATUS);
1429 	}
1430 
1431 	result = IRQ_HANDLED;
1432 
1433 	mmiowb();
1434 out:
1435 	spin_unlock(&host->lock);
1436 
1437 	/*
1438 	 * We have to delay this as it calls back into the driver.
1439 	 */
1440 	if (cardint)
1441 		mmc_signal_sdio_irq(host->mmc);
1442 
1443 	return result;
1444 }
1445 
1446 /*****************************************************************************\
1447  *                                                                           *
1448  * Suspend/resume                                                            *
1449  *                                                                           *
1450 \*****************************************************************************/
1451 
1452 #ifdef CONFIG_PM
1453 
1454 int sdhci_suspend_host(struct sdhci_host *host, pm_message_t state)
1455 {
1456 	int ret;
1457 
1458 	ret = mmc_suspend_host(host->mmc, state);
1459 	if (ret)
1460 		return ret;
1461 
1462 	free_irq(host->irq, host);
1463 
1464 	return 0;
1465 }
1466 
1467 EXPORT_SYMBOL_GPL(sdhci_suspend_host);
1468 
1469 int sdhci_resume_host(struct sdhci_host *host)
1470 {
1471 	int ret;
1472 
1473 	if (host->flags & SDHCI_USE_DMA) {
1474 		if (host->ops->enable_dma)
1475 			host->ops->enable_dma(host);
1476 	}
1477 
1478 	ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
1479 			  mmc_hostname(host->mmc), host);
1480 	if (ret)
1481 		return ret;
1482 
1483 	sdhci_init(host);
1484 	mmiowb();
1485 
1486 	ret = mmc_resume_host(host->mmc);
1487 	if (ret)
1488 		return ret;
1489 
1490 	return 0;
1491 }
1492 
1493 EXPORT_SYMBOL_GPL(sdhci_resume_host);
1494 
1495 #endif /* CONFIG_PM */
1496 
1497 /*****************************************************************************\
1498  *                                                                           *
1499  * Device allocation/registration                                            *
1500  *                                                                           *
1501 \*****************************************************************************/
1502 
1503 struct sdhci_host *sdhci_alloc_host(struct device *dev,
1504 	size_t priv_size)
1505 {
1506 	struct mmc_host *mmc;
1507 	struct sdhci_host *host;
1508 
1509 	WARN_ON(dev == NULL);
1510 
1511 	mmc = mmc_alloc_host(sizeof(struct sdhci_host) + priv_size, dev);
1512 	if (!mmc)
1513 		return ERR_PTR(-ENOMEM);
1514 
1515 	host = mmc_priv(mmc);
1516 	host->mmc = mmc;
1517 
1518 	return host;
1519 }
1520 
1521 EXPORT_SYMBOL_GPL(sdhci_alloc_host);
1522 
1523 int sdhci_add_host(struct sdhci_host *host)
1524 {
1525 	struct mmc_host *mmc;
1526 	unsigned int caps;
1527 	int ret;
1528 
1529 	WARN_ON(host == NULL);
1530 	if (host == NULL)
1531 		return -EINVAL;
1532 
1533 	mmc = host->mmc;
1534 
1535 	if (debug_quirks)
1536 		host->quirks = debug_quirks;
1537 
1538 	sdhci_reset(host, SDHCI_RESET_ALL);
1539 
1540 	host->version = readw(host->ioaddr + SDHCI_HOST_VERSION);
1541 	host->version = (host->version & SDHCI_SPEC_VER_MASK)
1542 				>> SDHCI_SPEC_VER_SHIFT;
1543 	if (host->version > SDHCI_SPEC_200) {
1544 		printk(KERN_ERR "%s: Unknown controller version (%d). "
1545 			"You may experience problems.\n", mmc_hostname(mmc),
1546 			host->version);
1547 	}
1548 
1549 	caps = readl(host->ioaddr + SDHCI_CAPABILITIES);
1550 
1551 	if (host->quirks & SDHCI_QUIRK_FORCE_DMA)
1552 		host->flags |= SDHCI_USE_DMA;
1553 	else if (!(caps & SDHCI_CAN_DO_DMA))
1554 		DBG("Controller doesn't have DMA capability\n");
1555 	else
1556 		host->flags |= SDHCI_USE_DMA;
1557 
1558 	if ((host->quirks & SDHCI_QUIRK_BROKEN_DMA) &&
1559 		(host->flags & SDHCI_USE_DMA)) {
1560 		DBG("Disabling DMA as it is marked broken\n");
1561 		host->flags &= ~SDHCI_USE_DMA;
1562 	}
1563 
1564 	if (host->flags & SDHCI_USE_DMA) {
1565 		if ((host->version >= SDHCI_SPEC_200) &&
1566 				(caps & SDHCI_CAN_DO_ADMA2))
1567 			host->flags |= SDHCI_USE_ADMA;
1568 	}
1569 
1570 	if ((host->quirks & SDHCI_QUIRK_BROKEN_ADMA) &&
1571 		(host->flags & SDHCI_USE_ADMA)) {
1572 		DBG("Disabling ADMA as it is marked broken\n");
1573 		host->flags &= ~SDHCI_USE_ADMA;
1574 	}
1575 
1576 	if (host->flags & SDHCI_USE_DMA) {
1577 		if (host->ops->enable_dma) {
1578 			if (host->ops->enable_dma(host)) {
1579 				printk(KERN_WARNING "%s: No suitable DMA "
1580 					"available. Falling back to PIO.\n",
1581 					mmc_hostname(mmc));
1582 				host->flags &= ~(SDHCI_USE_DMA | SDHCI_USE_ADMA);
1583 			}
1584 		}
1585 	}
1586 
1587 	if (host->flags & SDHCI_USE_ADMA) {
1588 		/*
1589 		 * We need to allocate descriptors for all sg entries
1590 		 * (128) and potentially one alignment transfer for
1591 		 * each of those entries.
1592 		 */
1593 		host->adma_desc = kmalloc((128 * 2 + 1) * 4, GFP_KERNEL);
1594 		host->align_buffer = kmalloc(128 * 4, GFP_KERNEL);
1595 		if (!host->adma_desc || !host->align_buffer) {
1596 			kfree(host->adma_desc);
1597 			kfree(host->align_buffer);
1598 			printk(KERN_WARNING "%s: Unable to allocate ADMA "
1599 				"buffers. Falling back to standard DMA.\n",
1600 				mmc_hostname(mmc));
1601 			host->flags &= ~SDHCI_USE_ADMA;
1602 		}
1603 	}
1604 
1605 	/*
1606 	 * If we use DMA, then it's up to the caller to set the DMA
1607 	 * mask, but PIO does not need the hw shim so we set a new
1608 	 * mask here in that case.
1609 	 */
1610 	if (!(host->flags & SDHCI_USE_DMA)) {
1611 		host->dma_mask = DMA_BIT_MASK(64);
1612 		mmc_dev(host->mmc)->dma_mask = &host->dma_mask;
1613 	}
1614 
1615 	host->max_clk =
1616 		(caps & SDHCI_CLOCK_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
1617 	if (host->max_clk == 0) {
1618 		printk(KERN_ERR "%s: Hardware doesn't specify base clock "
1619 			"frequency.\n", mmc_hostname(mmc));
1620 		return -ENODEV;
1621 	}
1622 	host->max_clk *= 1000000;
1623 
1624 	host->timeout_clk =
1625 		(caps & SDHCI_TIMEOUT_CLK_MASK) >> SDHCI_TIMEOUT_CLK_SHIFT;
1626 	if (host->timeout_clk == 0) {
1627 		printk(KERN_ERR "%s: Hardware doesn't specify timeout clock "
1628 			"frequency.\n", mmc_hostname(mmc));
1629 		return -ENODEV;
1630 	}
1631 	if (caps & SDHCI_TIMEOUT_CLK_UNIT)
1632 		host->timeout_clk *= 1000;
1633 
1634 	/*
1635 	 * Set host parameters.
1636 	 */
1637 	mmc->ops = &sdhci_ops;
1638 	mmc->f_min = host->max_clk / 256;
1639 	mmc->f_max = host->max_clk;
1640 	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1641 
1642 	if (caps & SDHCI_CAN_DO_HISPD)
1643 		mmc->caps |= MMC_CAP_SD_HIGHSPEED;
1644 
1645 	mmc->ocr_avail = 0;
1646 	if (caps & SDHCI_CAN_VDD_330)
1647 		mmc->ocr_avail |= MMC_VDD_32_33|MMC_VDD_33_34;
1648 	if (caps & SDHCI_CAN_VDD_300)
1649 		mmc->ocr_avail |= MMC_VDD_29_30|MMC_VDD_30_31;
1650 	if (caps & SDHCI_CAN_VDD_180)
1651 		mmc->ocr_avail |= MMC_VDD_165_195;
1652 
1653 	if (mmc->ocr_avail == 0) {
1654 		printk(KERN_ERR "%s: Hardware doesn't report any "
1655 			"support voltages.\n", mmc_hostname(mmc));
1656 		return -ENODEV;
1657 	}
1658 
1659 	spin_lock_init(&host->lock);
1660 
1661 	/*
1662 	 * Maximum number of segments. Depends on if the hardware
1663 	 * can do scatter/gather or not.
1664 	 */
1665 	if (host->flags & SDHCI_USE_ADMA)
1666 		mmc->max_hw_segs = 128;
1667 	else if (host->flags & SDHCI_USE_DMA)
1668 		mmc->max_hw_segs = 1;
1669 	else /* PIO */
1670 		mmc->max_hw_segs = 128;
1671 	mmc->max_phys_segs = 128;
1672 
1673 	/*
1674 	 * Maximum number of sectors in one transfer. Limited by DMA boundary
1675 	 * size (512KiB).
1676 	 */
1677 	mmc->max_req_size = 524288;
1678 
1679 	/*
1680 	 * Maximum segment size. Could be one segment with the maximum number
1681 	 * of bytes. When doing hardware scatter/gather, each entry cannot
1682 	 * be larger than 64 KiB though.
1683 	 */
1684 	if (host->flags & SDHCI_USE_ADMA)
1685 		mmc->max_seg_size = 65536;
1686 	else
1687 		mmc->max_seg_size = mmc->max_req_size;
1688 
1689 	/*
1690 	 * Maximum block size. This varies from controller to controller and
1691 	 * is specified in the capabilities register.
1692 	 */
1693 	mmc->max_blk_size = (caps & SDHCI_MAX_BLOCK_MASK) >> SDHCI_MAX_BLOCK_SHIFT;
1694 	if (mmc->max_blk_size >= 3) {
1695 		printk(KERN_WARNING "%s: Invalid maximum block size, "
1696 			"assuming 512 bytes\n", mmc_hostname(mmc));
1697 		mmc->max_blk_size = 512;
1698 	} else
1699 		mmc->max_blk_size = 512 << mmc->max_blk_size;
1700 
1701 	/*
1702 	 * Maximum block count.
1703 	 */
1704 	mmc->max_blk_count = 65535;
1705 
1706 	/*
1707 	 * Init tasklets.
1708 	 */
1709 	tasklet_init(&host->card_tasklet,
1710 		sdhci_tasklet_card, (unsigned long)host);
1711 	tasklet_init(&host->finish_tasklet,
1712 		sdhci_tasklet_finish, (unsigned long)host);
1713 
1714 	setup_timer(&host->timer, sdhci_timeout_timer, (unsigned long)host);
1715 
1716 	ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
1717 		mmc_hostname(mmc), host);
1718 	if (ret)
1719 		goto untasklet;
1720 
1721 	sdhci_init(host);
1722 
1723 #ifdef CONFIG_MMC_DEBUG
1724 	sdhci_dumpregs(host);
1725 #endif
1726 
1727 #ifdef SDHCI_USE_LEDS_CLASS
1728 	snprintf(host->led_name, sizeof(host->led_name),
1729 		"%s::", mmc_hostname(mmc));
1730 	host->led.name = host->led_name;
1731 	host->led.brightness = LED_OFF;
1732 	host->led.default_trigger = mmc_hostname(mmc);
1733 	host->led.brightness_set = sdhci_led_control;
1734 
1735 	ret = led_classdev_register(mmc_dev(mmc), &host->led);
1736 	if (ret)
1737 		goto reset;
1738 #endif
1739 
1740 	mmiowb();
1741 
1742 	mmc_add_host(mmc);
1743 
1744 	printk(KERN_INFO "%s: SDHCI controller on %s [%s] using %s%s\n",
1745 		mmc_hostname(mmc), host->hw_name, dev_name(mmc_dev(mmc)),
1746 		(host->flags & SDHCI_USE_ADMA)?"A":"",
1747 		(host->flags & SDHCI_USE_DMA)?"DMA":"PIO");
1748 
1749 	return 0;
1750 
1751 #ifdef SDHCI_USE_LEDS_CLASS
1752 reset:
1753 	sdhci_reset(host, SDHCI_RESET_ALL);
1754 	free_irq(host->irq, host);
1755 #endif
1756 untasklet:
1757 	tasklet_kill(&host->card_tasklet);
1758 	tasklet_kill(&host->finish_tasklet);
1759 
1760 	return ret;
1761 }
1762 
1763 EXPORT_SYMBOL_GPL(sdhci_add_host);
1764 
1765 void sdhci_remove_host(struct sdhci_host *host, int dead)
1766 {
1767 	unsigned long flags;
1768 
1769 	if (dead) {
1770 		spin_lock_irqsave(&host->lock, flags);
1771 
1772 		host->flags |= SDHCI_DEVICE_DEAD;
1773 
1774 		if (host->mrq) {
1775 			printk(KERN_ERR "%s: Controller removed during "
1776 				" transfer!\n", mmc_hostname(host->mmc));
1777 
1778 			host->mrq->cmd->error = -ENOMEDIUM;
1779 			tasklet_schedule(&host->finish_tasklet);
1780 		}
1781 
1782 		spin_unlock_irqrestore(&host->lock, flags);
1783 	}
1784 
1785 	mmc_remove_host(host->mmc);
1786 
1787 #ifdef SDHCI_USE_LEDS_CLASS
1788 	led_classdev_unregister(&host->led);
1789 #endif
1790 
1791 	if (!dead)
1792 		sdhci_reset(host, SDHCI_RESET_ALL);
1793 
1794 	free_irq(host->irq, host);
1795 
1796 	del_timer_sync(&host->timer);
1797 
1798 	tasklet_kill(&host->card_tasklet);
1799 	tasklet_kill(&host->finish_tasklet);
1800 
1801 	kfree(host->adma_desc);
1802 	kfree(host->align_buffer);
1803 
1804 	host->adma_desc = NULL;
1805 	host->align_buffer = NULL;
1806 }
1807 
1808 EXPORT_SYMBOL_GPL(sdhci_remove_host);
1809 
1810 void sdhci_free_host(struct sdhci_host *host)
1811 {
1812 	mmc_free_host(host->mmc);
1813 }
1814 
1815 EXPORT_SYMBOL_GPL(sdhci_free_host);
1816 
1817 /*****************************************************************************\
1818  *                                                                           *
1819  * Driver init/exit                                                          *
1820  *                                                                           *
1821 \*****************************************************************************/
1822 
1823 static int __init sdhci_drv_init(void)
1824 {
1825 	printk(KERN_INFO DRIVER_NAME
1826 		": Secure Digital Host Controller Interface driver\n");
1827 	printk(KERN_INFO DRIVER_NAME ": Copyright(c) Pierre Ossman\n");
1828 
1829 	return 0;
1830 }
1831 
1832 static void __exit sdhci_drv_exit(void)
1833 {
1834 }
1835 
1836 module_init(sdhci_drv_init);
1837 module_exit(sdhci_drv_exit);
1838 
1839 module_param(debug_quirks, uint, 0444);
1840 
1841 MODULE_AUTHOR("Pierre Ossman <drzeus@drzeus.cx>");
1842 MODULE_DESCRIPTION("Secure Digital Host Controller Interface core driver");
1843 MODULE_LICENSE("GPL");
1844 
1845 MODULE_PARM_DESC(debug_quirks, "Force certain quirks.");
1846