xref: /linux/drivers/mmc/host/au1xmmc.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * linux/drivers/mmc/host/au1xmmc.c - AU1XX0 MMC driver
3  *
4  *  Copyright (c) 2005, Advanced Micro Devices, Inc.
5  *
6  *  Developed with help from the 2.4.30 MMC AU1XXX controller including
7  *  the following copyright notices:
8  *     Copyright (c) 2003-2004 Embedded Edge, LLC.
9  *     Portions Copyright (C) 2002 Embedix, Inc
10  *     Copyright 2002 Hewlett-Packard Company
11 
12  *  2.6 version of this driver inspired by:
13  *     (drivers/mmc/wbsd.c) Copyright (C) 2004-2005 Pierre Ossman,
14  *     All Rights Reserved.
15  *     (drivers/mmc/pxa.c) Copyright (C) 2003 Russell King,
16  *     All Rights Reserved.
17  *
18 
19  * This program is free software; you can redistribute it and/or modify
20  * it under the terms of the GNU General Public License version 2 as
21  * published by the Free Software Foundation.
22  */
23 
24 /* Why don't we use the SD controllers' carddetect feature?
25  *
26  * From the AU1100 MMC application guide:
27  * If the Au1100-based design is intended to support both MultiMediaCards
28  * and 1- or 4-data bit SecureDigital cards, then the solution is to
29  * connect a weak (560KOhm) pull-up resistor to connector pin 1.
30  * In doing so, a MMC card never enters SPI-mode communications,
31  * but now the SecureDigital card-detect feature of CD/DAT3 is ineffective
32  * (the low to high transition will not occur).
33  */
34 
35 #include <linux/module.h>
36 #include <linux/init.h>
37 #include <linux/platform_device.h>
38 #include <linux/mm.h>
39 #include <linux/interrupt.h>
40 #include <linux/dma-mapping.h>
41 #include <linux/scatterlist.h>
42 #include <linux/leds.h>
43 #include <linux/mmc/host.h>
44 #include <linux/slab.h>
45 
46 #include <asm/io.h>
47 #include <asm/mach-au1x00/au1000.h>
48 #include <asm/mach-au1x00/au1xxx_dbdma.h>
49 #include <asm/mach-au1x00/au1100_mmc.h>
50 
51 #define DRIVER_NAME "au1xxx-mmc"
52 
53 /* Set this to enable special debugging macros */
54 /* #define DEBUG */
55 
56 #ifdef DEBUG
57 #define DBG(fmt, idx, args...)	\
58 	pr_debug("au1xmmc(%d): DEBUG: " fmt, idx, ##args)
59 #else
60 #define DBG(fmt, idx, args...) do {} while (0)
61 #endif
62 
63 /* Hardware definitions */
64 #define AU1XMMC_DESCRIPTOR_COUNT 1
65 
66 /* max DMA seg size: 64KB on Au1100, 4MB on Au1200 */
67 #define AU1100_MMC_DESCRIPTOR_SIZE 0x0000ffff
68 #define AU1200_MMC_DESCRIPTOR_SIZE 0x003fffff
69 
70 #define AU1XMMC_OCR (MMC_VDD_27_28 | MMC_VDD_28_29 | MMC_VDD_29_30 | \
71 		     MMC_VDD_30_31 | MMC_VDD_31_32 | MMC_VDD_32_33 | \
72 		     MMC_VDD_33_34 | MMC_VDD_34_35 | MMC_VDD_35_36)
73 
74 /* This gives us a hard value for the stop command that we can write directly
75  * to the command register.
76  */
77 #define STOP_CMD	\
78 	(SD_CMD_RT_1B | SD_CMD_CT_7 | (0xC << SD_CMD_CI_SHIFT) | SD_CMD_GO)
79 
80 /* This is the set of interrupts that we configure by default. */
81 #define AU1XMMC_INTERRUPTS 				\
82 	(SD_CONFIG_SC | SD_CONFIG_DT | SD_CONFIG_RAT |	\
83 	 SD_CONFIG_CR | SD_CONFIG_I)
84 
85 /* The poll event (looking for insert/remove events runs twice a second. */
86 #define AU1XMMC_DETECT_TIMEOUT (HZ/2)
87 
88 struct au1xmmc_host {
89 	struct mmc_host *mmc;
90 	struct mmc_request *mrq;
91 
92 	u32 flags;
93 	u32 iobase;
94 	u32 clock;
95 	u32 bus_width;
96 	u32 power_mode;
97 
98 	int status;
99 
100 	struct {
101 		int len;
102 		int dir;
103 	} dma;
104 
105 	struct {
106 		int index;
107 		int offset;
108 		int len;
109 	} pio;
110 
111 	u32 tx_chan;
112 	u32 rx_chan;
113 
114 	int irq;
115 
116 	struct tasklet_struct finish_task;
117 	struct tasklet_struct data_task;
118 	struct au1xmmc_platform_data *platdata;
119 	struct platform_device *pdev;
120 	struct resource *ioarea;
121 };
122 
123 /* Status flags used by the host structure */
124 #define HOST_F_XMIT	0x0001
125 #define HOST_F_RECV	0x0002
126 #define HOST_F_DMA	0x0010
127 #define HOST_F_DBDMA	0x0020
128 #define HOST_F_ACTIVE	0x0100
129 #define HOST_F_STOP	0x1000
130 
131 #define HOST_S_IDLE	0x0001
132 #define HOST_S_CMD	0x0002
133 #define HOST_S_DATA	0x0003
134 #define HOST_S_STOP	0x0004
135 
136 /* Easy access macros */
137 #define HOST_STATUS(h)	((h)->iobase + SD_STATUS)
138 #define HOST_CONFIG(h)	((h)->iobase + SD_CONFIG)
139 #define HOST_ENABLE(h)	((h)->iobase + SD_ENABLE)
140 #define HOST_TXPORT(h)	((h)->iobase + SD_TXPORT)
141 #define HOST_RXPORT(h)	((h)->iobase + SD_RXPORT)
142 #define HOST_CMDARG(h)	((h)->iobase + SD_CMDARG)
143 #define HOST_BLKSIZE(h)	((h)->iobase + SD_BLKSIZE)
144 #define HOST_CMD(h)	((h)->iobase + SD_CMD)
145 #define HOST_CONFIG2(h)	((h)->iobase + SD_CONFIG2)
146 #define HOST_TIMEOUT(h)	((h)->iobase + SD_TIMEOUT)
147 #define HOST_DEBUG(h)	((h)->iobase + SD_DEBUG)
148 
149 #define DMA_CHANNEL(h)	\
150 	(((h)->flags & HOST_F_XMIT) ? (h)->tx_chan : (h)->rx_chan)
151 
152 static inline int has_dbdma(void)
153 {
154 	switch (alchemy_get_cputype()) {
155 	case ALCHEMY_CPU_AU1200:
156 		return 1;
157 	default:
158 		return 0;
159 	}
160 }
161 
162 static inline void IRQ_ON(struct au1xmmc_host *host, u32 mask)
163 {
164 	u32 val = au_readl(HOST_CONFIG(host));
165 	val |= mask;
166 	au_writel(val, HOST_CONFIG(host));
167 	au_sync();
168 }
169 
170 static inline void FLUSH_FIFO(struct au1xmmc_host *host)
171 {
172 	u32 val = au_readl(HOST_CONFIG2(host));
173 
174 	au_writel(val | SD_CONFIG2_FF, HOST_CONFIG2(host));
175 	au_sync_delay(1);
176 
177 	/* SEND_STOP will turn off clock control - this re-enables it */
178 	val &= ~SD_CONFIG2_DF;
179 
180 	au_writel(val, HOST_CONFIG2(host));
181 	au_sync();
182 }
183 
184 static inline void IRQ_OFF(struct au1xmmc_host *host, u32 mask)
185 {
186 	u32 val = au_readl(HOST_CONFIG(host));
187 	val &= ~mask;
188 	au_writel(val, HOST_CONFIG(host));
189 	au_sync();
190 }
191 
192 static inline void SEND_STOP(struct au1xmmc_host *host)
193 {
194 	u32 config2;
195 
196 	WARN_ON(host->status != HOST_S_DATA);
197 	host->status = HOST_S_STOP;
198 
199 	config2 = au_readl(HOST_CONFIG2(host));
200 	au_writel(config2 | SD_CONFIG2_DF, HOST_CONFIG2(host));
201 	au_sync();
202 
203 	/* Send the stop command */
204 	au_writel(STOP_CMD, HOST_CMD(host));
205 }
206 
207 static void au1xmmc_set_power(struct au1xmmc_host *host, int state)
208 {
209 	if (host->platdata && host->platdata->set_power)
210 		host->platdata->set_power(host->mmc, state);
211 }
212 
213 static int au1xmmc_card_inserted(struct mmc_host *mmc)
214 {
215 	struct au1xmmc_host *host = mmc_priv(mmc);
216 
217 	if (host->platdata && host->platdata->card_inserted)
218 		return !!host->platdata->card_inserted(host->mmc);
219 
220 	return -ENOSYS;
221 }
222 
223 static int au1xmmc_card_readonly(struct mmc_host *mmc)
224 {
225 	struct au1xmmc_host *host = mmc_priv(mmc);
226 
227 	if (host->platdata && host->platdata->card_readonly)
228 		return !!host->platdata->card_readonly(mmc);
229 
230 	return -ENOSYS;
231 }
232 
233 static void au1xmmc_finish_request(struct au1xmmc_host *host)
234 {
235 	struct mmc_request *mrq = host->mrq;
236 
237 	host->mrq = NULL;
238 	host->flags &= HOST_F_ACTIVE | HOST_F_DMA;
239 
240 	host->dma.len = 0;
241 	host->dma.dir = 0;
242 
243 	host->pio.index  = 0;
244 	host->pio.offset = 0;
245 	host->pio.len = 0;
246 
247 	host->status = HOST_S_IDLE;
248 
249 	mmc_request_done(host->mmc, mrq);
250 }
251 
252 static void au1xmmc_tasklet_finish(unsigned long param)
253 {
254 	struct au1xmmc_host *host = (struct au1xmmc_host *) param;
255 	au1xmmc_finish_request(host);
256 }
257 
258 static int au1xmmc_send_command(struct au1xmmc_host *host, int wait,
259 				struct mmc_command *cmd, struct mmc_data *data)
260 {
261 	u32 mmccmd = (cmd->opcode << SD_CMD_CI_SHIFT);
262 
263 	switch (mmc_resp_type(cmd)) {
264 	case MMC_RSP_NONE:
265 		break;
266 	case MMC_RSP_R1:
267 		mmccmd |= SD_CMD_RT_1;
268 		break;
269 	case MMC_RSP_R1B:
270 		mmccmd |= SD_CMD_RT_1B;
271 		break;
272 	case MMC_RSP_R2:
273 		mmccmd |= SD_CMD_RT_2;
274 		break;
275 	case MMC_RSP_R3:
276 		mmccmd |= SD_CMD_RT_3;
277 		break;
278 	default:
279 		pr_info("au1xmmc: unhandled response type %02x\n",
280 			mmc_resp_type(cmd));
281 		return -EINVAL;
282 	}
283 
284 	if (data) {
285 		if (data->flags & MMC_DATA_READ) {
286 			if (data->blocks > 1)
287 				mmccmd |= SD_CMD_CT_4;
288 			else
289 				mmccmd |= SD_CMD_CT_2;
290 		} else if (data->flags & MMC_DATA_WRITE) {
291 			if (data->blocks > 1)
292 				mmccmd |= SD_CMD_CT_3;
293 			else
294 				mmccmd |= SD_CMD_CT_1;
295 		}
296 	}
297 
298 	au_writel(cmd->arg, HOST_CMDARG(host));
299 	au_sync();
300 
301 	if (wait)
302 		IRQ_OFF(host, SD_CONFIG_CR);
303 
304 	au_writel((mmccmd | SD_CMD_GO), HOST_CMD(host));
305 	au_sync();
306 
307 	/* Wait for the command to go on the line */
308 	while (au_readl(HOST_CMD(host)) & SD_CMD_GO)
309 		/* nop */;
310 
311 	/* Wait for the command to come back */
312 	if (wait) {
313 		u32 status = au_readl(HOST_STATUS(host));
314 
315 		while (!(status & SD_STATUS_CR))
316 			status = au_readl(HOST_STATUS(host));
317 
318 		/* Clear the CR status */
319 		au_writel(SD_STATUS_CR, HOST_STATUS(host));
320 
321 		IRQ_ON(host, SD_CONFIG_CR);
322 	}
323 
324 	return 0;
325 }
326 
327 static void au1xmmc_data_complete(struct au1xmmc_host *host, u32 status)
328 {
329 	struct mmc_request *mrq = host->mrq;
330 	struct mmc_data *data;
331 	u32 crc;
332 
333 	WARN_ON((host->status != HOST_S_DATA) && (host->status != HOST_S_STOP));
334 
335 	if (host->mrq == NULL)
336 		return;
337 
338 	data = mrq->cmd->data;
339 
340 	if (status == 0)
341 		status = au_readl(HOST_STATUS(host));
342 
343 	/* The transaction is really over when the SD_STATUS_DB bit is clear */
344 	while ((host->flags & HOST_F_XMIT) && (status & SD_STATUS_DB))
345 		status = au_readl(HOST_STATUS(host));
346 
347 	data->error = 0;
348 	dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len, host->dma.dir);
349 
350         /* Process any errors */
351 	crc = (status & (SD_STATUS_WC | SD_STATUS_RC));
352 	if (host->flags & HOST_F_XMIT)
353 		crc |= ((status & 0x07) == 0x02) ? 0 : 1;
354 
355 	if (crc)
356 		data->error = -EILSEQ;
357 
358 	/* Clear the CRC bits */
359 	au_writel(SD_STATUS_WC | SD_STATUS_RC, HOST_STATUS(host));
360 
361 	data->bytes_xfered = 0;
362 
363 	if (!data->error) {
364 		if (host->flags & (HOST_F_DMA | HOST_F_DBDMA)) {
365 			u32 chan = DMA_CHANNEL(host);
366 
367 			chan_tab_t *c = *((chan_tab_t **)chan);
368 			au1x_dma_chan_t *cp = c->chan_ptr;
369 			data->bytes_xfered = cp->ddma_bytecnt;
370 		} else
371 			data->bytes_xfered =
372 				(data->blocks * data->blksz) - host->pio.len;
373 	}
374 
375 	au1xmmc_finish_request(host);
376 }
377 
378 static void au1xmmc_tasklet_data(unsigned long param)
379 {
380 	struct au1xmmc_host *host = (struct au1xmmc_host *)param;
381 
382 	u32 status = au_readl(HOST_STATUS(host));
383 	au1xmmc_data_complete(host, status);
384 }
385 
386 #define AU1XMMC_MAX_TRANSFER 8
387 
388 static void au1xmmc_send_pio(struct au1xmmc_host *host)
389 {
390 	struct mmc_data *data;
391 	int sg_len, max, count;
392 	unsigned char *sg_ptr, val;
393 	u32 status;
394 	struct scatterlist *sg;
395 
396 	data = host->mrq->data;
397 
398 	if (!(host->flags & HOST_F_XMIT))
399 		return;
400 
401 	/* This is the pointer to the data buffer */
402 	sg = &data->sg[host->pio.index];
403 	sg_ptr = sg_virt(sg) + host->pio.offset;
404 
405 	/* This is the space left inside the buffer */
406 	sg_len = data->sg[host->pio.index].length - host->pio.offset;
407 
408 	/* Check if we need less than the size of the sg_buffer */
409 	max = (sg_len > host->pio.len) ? host->pio.len : sg_len;
410 	if (max > AU1XMMC_MAX_TRANSFER)
411 		max = AU1XMMC_MAX_TRANSFER;
412 
413 	for (count = 0; count < max; count++) {
414 		status = au_readl(HOST_STATUS(host));
415 
416 		if (!(status & SD_STATUS_TH))
417 			break;
418 
419 		val = *sg_ptr++;
420 
421 		au_writel((unsigned long)val, HOST_TXPORT(host));
422 		au_sync();
423 	}
424 
425 	host->pio.len -= count;
426 	host->pio.offset += count;
427 
428 	if (count == sg_len) {
429 		host->pio.index++;
430 		host->pio.offset = 0;
431 	}
432 
433 	if (host->pio.len == 0) {
434 		IRQ_OFF(host, SD_CONFIG_TH);
435 
436 		if (host->flags & HOST_F_STOP)
437 			SEND_STOP(host);
438 
439 		tasklet_schedule(&host->data_task);
440 	}
441 }
442 
443 static void au1xmmc_receive_pio(struct au1xmmc_host *host)
444 {
445 	struct mmc_data *data;
446 	int max, count, sg_len = 0;
447 	unsigned char *sg_ptr = NULL;
448 	u32 status, val;
449 	struct scatterlist *sg;
450 
451 	data = host->mrq->data;
452 
453 	if (!(host->flags & HOST_F_RECV))
454 		return;
455 
456 	max = host->pio.len;
457 
458 	if (host->pio.index < host->dma.len) {
459 		sg = &data->sg[host->pio.index];
460 		sg_ptr = sg_virt(sg) + host->pio.offset;
461 
462 		/* This is the space left inside the buffer */
463 		sg_len = sg_dma_len(&data->sg[host->pio.index]) - host->pio.offset;
464 
465 		/* Check if we need less than the size of the sg_buffer */
466 		if (sg_len < max)
467 			max = sg_len;
468 	}
469 
470 	if (max > AU1XMMC_MAX_TRANSFER)
471 		max = AU1XMMC_MAX_TRANSFER;
472 
473 	for (count = 0; count < max; count++) {
474 		status = au_readl(HOST_STATUS(host));
475 
476 		if (!(status & SD_STATUS_NE))
477 			break;
478 
479 		if (status & SD_STATUS_RC) {
480 			DBG("RX CRC Error [%d + %d].\n", host->pdev->id,
481 					host->pio.len, count);
482 			break;
483 		}
484 
485 		if (status & SD_STATUS_RO) {
486 			DBG("RX Overrun [%d + %d]\n", host->pdev->id,
487 					host->pio.len, count);
488 			break;
489 		}
490 		else if (status & SD_STATUS_RU) {
491 			DBG("RX Underrun [%d + %d]\n", host->pdev->id,
492 					host->pio.len,	count);
493 			break;
494 		}
495 
496 		val = au_readl(HOST_RXPORT(host));
497 
498 		if (sg_ptr)
499 			*sg_ptr++ = (unsigned char)(val & 0xFF);
500 	}
501 
502 	host->pio.len -= count;
503 	host->pio.offset += count;
504 
505 	if (sg_len && count == sg_len) {
506 		host->pio.index++;
507 		host->pio.offset = 0;
508 	}
509 
510 	if (host->pio.len == 0) {
511 		/* IRQ_OFF(host, SD_CONFIG_RA | SD_CONFIG_RF); */
512 		IRQ_OFF(host, SD_CONFIG_NE);
513 
514 		if (host->flags & HOST_F_STOP)
515 			SEND_STOP(host);
516 
517 		tasklet_schedule(&host->data_task);
518 	}
519 }
520 
521 /* This is called when a command has been completed - grab the response
522  * and check for errors.  Then start the data transfer if it is indicated.
523  */
524 static void au1xmmc_cmd_complete(struct au1xmmc_host *host, u32 status)
525 {
526 	struct mmc_request *mrq = host->mrq;
527 	struct mmc_command *cmd;
528 	u32 r[4];
529 	int i, trans;
530 
531 	if (!host->mrq)
532 		return;
533 
534 	cmd = mrq->cmd;
535 	cmd->error = 0;
536 
537 	if (cmd->flags & MMC_RSP_PRESENT) {
538 		if (cmd->flags & MMC_RSP_136) {
539 			r[0] = au_readl(host->iobase + SD_RESP3);
540 			r[1] = au_readl(host->iobase + SD_RESP2);
541 			r[2] = au_readl(host->iobase + SD_RESP1);
542 			r[3] = au_readl(host->iobase + SD_RESP0);
543 
544 			/* The CRC is omitted from the response, so really
545 			 * we only got 120 bytes, but the engine expects
546 			 * 128 bits, so we have to shift things up.
547 			 */
548 			for (i = 0; i < 4; i++) {
549 				cmd->resp[i] = (r[i] & 0x00FFFFFF) << 8;
550 				if (i != 3)
551 					cmd->resp[i] |= (r[i + 1] & 0xFF000000) >> 24;
552 			}
553 		} else {
554 			/* Techincally, we should be getting all 48 bits of
555 			 * the response (SD_RESP1 + SD_RESP2), but because
556 			 * our response omits the CRC, our data ends up
557 			 * being shifted 8 bits to the right.  In this case,
558 			 * that means that the OSR data starts at bit 31,
559 			 * so we can just read RESP0 and return that.
560 			 */
561 			cmd->resp[0] = au_readl(host->iobase + SD_RESP0);
562 		}
563 	}
564 
565         /* Figure out errors */
566 	if (status & (SD_STATUS_SC | SD_STATUS_WC | SD_STATUS_RC))
567 		cmd->error = -EILSEQ;
568 
569 	trans = host->flags & (HOST_F_XMIT | HOST_F_RECV);
570 
571 	if (!trans || cmd->error) {
572 		IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF);
573 		tasklet_schedule(&host->finish_task);
574 		return;
575 	}
576 
577 	host->status = HOST_S_DATA;
578 
579 	if ((host->flags & (HOST_F_DMA | HOST_F_DBDMA))) {
580 		u32 channel = DMA_CHANNEL(host);
581 
582 		/* Start the DBDMA as soon as the buffer gets something in it */
583 
584 		if (host->flags & HOST_F_RECV) {
585 			u32 mask = SD_STATUS_DB | SD_STATUS_NE;
586 
587 			while((status & mask) != mask)
588 				status = au_readl(HOST_STATUS(host));
589 		}
590 
591 		au1xxx_dbdma_start(channel);
592 	}
593 }
594 
595 static void au1xmmc_set_clock(struct au1xmmc_host *host, int rate)
596 {
597 	unsigned int pbus = get_au1x00_speed();
598 	unsigned int divisor;
599 	u32 config;
600 
601 	/* From databook:
602 	 * divisor = ((((cpuclock / sbus_divisor) / 2) / mmcclock) / 2) - 1
603 	 */
604 	pbus /= ((au_readl(SYS_POWERCTRL) & 0x3) + 2);
605 	pbus /= 2;
606 	divisor = ((pbus / rate) / 2) - 1;
607 
608 	config = au_readl(HOST_CONFIG(host));
609 
610 	config &= ~(SD_CONFIG_DIV);
611 	config |= (divisor & SD_CONFIG_DIV) | SD_CONFIG_DE;
612 
613 	au_writel(config, HOST_CONFIG(host));
614 	au_sync();
615 }
616 
617 static int au1xmmc_prepare_data(struct au1xmmc_host *host,
618 				struct mmc_data *data)
619 {
620 	int datalen = data->blocks * data->blksz;
621 
622 	if (data->flags & MMC_DATA_READ)
623 		host->flags |= HOST_F_RECV;
624 	else
625 		host->flags |= HOST_F_XMIT;
626 
627 	if (host->mrq->stop)
628 		host->flags |= HOST_F_STOP;
629 
630 	host->dma.dir = DMA_BIDIRECTIONAL;
631 
632 	host->dma.len = dma_map_sg(mmc_dev(host->mmc), data->sg,
633 				   data->sg_len, host->dma.dir);
634 
635 	if (host->dma.len == 0)
636 		return -ETIMEDOUT;
637 
638 	au_writel(data->blksz - 1, HOST_BLKSIZE(host));
639 
640 	if (host->flags & (HOST_F_DMA | HOST_F_DBDMA)) {
641 		int i;
642 		u32 channel = DMA_CHANNEL(host);
643 
644 		au1xxx_dbdma_stop(channel);
645 
646 		for (i = 0; i < host->dma.len; i++) {
647 			u32 ret = 0, flags = DDMA_FLAGS_NOIE;
648 			struct scatterlist *sg = &data->sg[i];
649 			int sg_len = sg->length;
650 
651 			int len = (datalen > sg_len) ? sg_len : datalen;
652 
653 			if (i == host->dma.len - 1)
654 				flags = DDMA_FLAGS_IE;
655 
656 			if (host->flags & HOST_F_XMIT) {
657 				ret = au1xxx_dbdma_put_source(channel,
658 					sg_phys(sg), len, flags);
659 			} else {
660 				ret = au1xxx_dbdma_put_dest(channel,
661 					sg_phys(sg), len, flags);
662 			}
663 
664 			if (!ret)
665 				goto dataerr;
666 
667 			datalen -= len;
668 		}
669 	} else {
670 		host->pio.index = 0;
671 		host->pio.offset = 0;
672 		host->pio.len = datalen;
673 
674 		if (host->flags & HOST_F_XMIT)
675 			IRQ_ON(host, SD_CONFIG_TH);
676 		else
677 			IRQ_ON(host, SD_CONFIG_NE);
678 			/* IRQ_ON(host, SD_CONFIG_RA | SD_CONFIG_RF); */
679 	}
680 
681 	return 0;
682 
683 dataerr:
684 	dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
685 			host->dma.dir);
686 	return -ETIMEDOUT;
687 }
688 
689 /* This actually starts a command or data transaction */
690 static void au1xmmc_request(struct mmc_host* mmc, struct mmc_request* mrq)
691 {
692 	struct au1xmmc_host *host = mmc_priv(mmc);
693 	int ret = 0;
694 
695 	WARN_ON(irqs_disabled());
696 	WARN_ON(host->status != HOST_S_IDLE);
697 
698 	host->mrq = mrq;
699 	host->status = HOST_S_CMD;
700 
701 	/* fail request immediately if no card is present */
702 	if (0 == au1xmmc_card_inserted(mmc)) {
703 		mrq->cmd->error = -ENOMEDIUM;
704 		au1xmmc_finish_request(host);
705 		return;
706 	}
707 
708 	if (mrq->data) {
709 		FLUSH_FIFO(host);
710 		ret = au1xmmc_prepare_data(host, mrq->data);
711 	}
712 
713 	if (!ret)
714 		ret = au1xmmc_send_command(host, 0, mrq->cmd, mrq->data);
715 
716 	if (ret) {
717 		mrq->cmd->error = ret;
718 		au1xmmc_finish_request(host);
719 	}
720 }
721 
722 static void au1xmmc_reset_controller(struct au1xmmc_host *host)
723 {
724 	/* Apply the clock */
725 	au_writel(SD_ENABLE_CE, HOST_ENABLE(host));
726         au_sync_delay(1);
727 
728 	au_writel(SD_ENABLE_R | SD_ENABLE_CE, HOST_ENABLE(host));
729 	au_sync_delay(5);
730 
731 	au_writel(~0, HOST_STATUS(host));
732 	au_sync();
733 
734 	au_writel(0, HOST_BLKSIZE(host));
735 	au_writel(0x001fffff, HOST_TIMEOUT(host));
736 	au_sync();
737 
738 	au_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
739         au_sync();
740 
741 	au_writel(SD_CONFIG2_EN | SD_CONFIG2_FF, HOST_CONFIG2(host));
742 	au_sync_delay(1);
743 
744 	au_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
745 	au_sync();
746 
747 	/* Configure interrupts */
748 	au_writel(AU1XMMC_INTERRUPTS, HOST_CONFIG(host));
749 	au_sync();
750 }
751 
752 
753 static void au1xmmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
754 {
755 	struct au1xmmc_host *host = mmc_priv(mmc);
756 	u32 config2;
757 
758 	if (ios->power_mode == MMC_POWER_OFF)
759 		au1xmmc_set_power(host, 0);
760 	else if (ios->power_mode == MMC_POWER_ON) {
761 		au1xmmc_set_power(host, 1);
762 	}
763 
764 	if (ios->clock && ios->clock != host->clock) {
765 		au1xmmc_set_clock(host, ios->clock);
766 		host->clock = ios->clock;
767 	}
768 
769 	config2 = au_readl(HOST_CONFIG2(host));
770 	switch (ios->bus_width) {
771 	case MMC_BUS_WIDTH_4:
772 		config2 |= SD_CONFIG2_WB;
773 		break;
774 	case MMC_BUS_WIDTH_1:
775 		config2 &= ~SD_CONFIG2_WB;
776 		break;
777 	}
778 	au_writel(config2, HOST_CONFIG2(host));
779 	au_sync();
780 }
781 
782 #define STATUS_TIMEOUT (SD_STATUS_RAT | SD_STATUS_DT)
783 #define STATUS_DATA_IN  (SD_STATUS_NE)
784 #define STATUS_DATA_OUT (SD_STATUS_TH)
785 
786 static irqreturn_t au1xmmc_irq(int irq, void *dev_id)
787 {
788 	struct au1xmmc_host *host = dev_id;
789 	u32 status;
790 
791 	status = au_readl(HOST_STATUS(host));
792 
793 	if (!(status & SD_STATUS_I))
794 		return IRQ_NONE;	/* not ours */
795 
796 	if (status & SD_STATUS_SI)	/* SDIO */
797 		mmc_signal_sdio_irq(host->mmc);
798 
799 	if (host->mrq && (status & STATUS_TIMEOUT)) {
800 		if (status & SD_STATUS_RAT)
801 			host->mrq->cmd->error = -ETIMEDOUT;
802 		else if (status & SD_STATUS_DT)
803 			host->mrq->data->error = -ETIMEDOUT;
804 
805 		/* In PIO mode, interrupts might still be enabled */
806 		IRQ_OFF(host, SD_CONFIG_NE | SD_CONFIG_TH);
807 
808 		/* IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF); */
809 		tasklet_schedule(&host->finish_task);
810 	}
811 #if 0
812 	else if (status & SD_STATUS_DD) {
813 		/* Sometimes we get a DD before a NE in PIO mode */
814 		if (!(host->flags & HOST_F_DMA) && (status & SD_STATUS_NE))
815 			au1xmmc_receive_pio(host);
816 		else {
817 			au1xmmc_data_complete(host, status);
818 			/* tasklet_schedule(&host->data_task); */
819 		}
820 	}
821 #endif
822 	else if (status & SD_STATUS_CR) {
823 		if (host->status == HOST_S_CMD)
824 			au1xmmc_cmd_complete(host, status);
825 
826 	} else if (!(host->flags & HOST_F_DMA)) {
827 		if ((host->flags & HOST_F_XMIT) && (status & STATUS_DATA_OUT))
828 			au1xmmc_send_pio(host);
829 		else if ((host->flags & HOST_F_RECV) && (status & STATUS_DATA_IN))
830 			au1xmmc_receive_pio(host);
831 
832 	} else if (status & 0x203F3C70) {
833 			DBG("Unhandled status %8.8x\n", host->pdev->id,
834 				status);
835 	}
836 
837 	au_writel(status, HOST_STATUS(host));
838 	au_sync();
839 
840 	return IRQ_HANDLED;
841 }
842 
843 /* 8bit memory DMA device */
844 static dbdev_tab_t au1xmmc_mem_dbdev = {
845 	.dev_id		= DSCR_CMD0_ALWAYS,
846 	.dev_flags	= DEV_FLAGS_ANYUSE,
847 	.dev_tsize	= 0,
848 	.dev_devwidth	= 8,
849 	.dev_physaddr	= 0x00000000,
850 	.dev_intlevel	= 0,
851 	.dev_intpolarity = 0,
852 };
853 static int memid;
854 
855 static void au1xmmc_dbdma_callback(int irq, void *dev_id)
856 {
857 	struct au1xmmc_host *host = (struct au1xmmc_host *)dev_id;
858 
859 	/* Avoid spurious interrupts */
860 	if (!host->mrq)
861 		return;
862 
863 	if (host->flags & HOST_F_STOP)
864 		SEND_STOP(host);
865 
866 	tasklet_schedule(&host->data_task);
867 }
868 
869 static int au1xmmc_dbdma_init(struct au1xmmc_host *host)
870 {
871 	struct resource *res;
872 	int txid, rxid;
873 
874 	res = platform_get_resource(host->pdev, IORESOURCE_DMA, 0);
875 	if (!res)
876 		return -ENODEV;
877 	txid = res->start;
878 
879 	res = platform_get_resource(host->pdev, IORESOURCE_DMA, 1);
880 	if (!res)
881 		return -ENODEV;
882 	rxid = res->start;
883 
884 	if (!memid)
885 		return -ENODEV;
886 
887 	host->tx_chan = au1xxx_dbdma_chan_alloc(memid, txid,
888 				au1xmmc_dbdma_callback, (void *)host);
889 	if (!host->tx_chan) {
890 		dev_err(&host->pdev->dev, "cannot allocate TX DMA\n");
891 		return -ENODEV;
892 	}
893 
894 	host->rx_chan = au1xxx_dbdma_chan_alloc(rxid, memid,
895 				au1xmmc_dbdma_callback, (void *)host);
896 	if (!host->rx_chan) {
897 		dev_err(&host->pdev->dev, "cannot allocate RX DMA\n");
898 		au1xxx_dbdma_chan_free(host->tx_chan);
899 		return -ENODEV;
900 	}
901 
902 	au1xxx_dbdma_set_devwidth(host->tx_chan, 8);
903 	au1xxx_dbdma_set_devwidth(host->rx_chan, 8);
904 
905 	au1xxx_dbdma_ring_alloc(host->tx_chan, AU1XMMC_DESCRIPTOR_COUNT);
906 	au1xxx_dbdma_ring_alloc(host->rx_chan, AU1XMMC_DESCRIPTOR_COUNT);
907 
908 	/* DBDMA is good to go */
909 	host->flags |= HOST_F_DMA | HOST_F_DBDMA;
910 
911 	return 0;
912 }
913 
914 static void au1xmmc_dbdma_shutdown(struct au1xmmc_host *host)
915 {
916 	if (host->flags & HOST_F_DMA) {
917 		host->flags &= ~HOST_F_DMA;
918 		au1xxx_dbdma_chan_free(host->tx_chan);
919 		au1xxx_dbdma_chan_free(host->rx_chan);
920 	}
921 }
922 
923 static void au1xmmc_enable_sdio_irq(struct mmc_host *mmc, int en)
924 {
925 	struct au1xmmc_host *host = mmc_priv(mmc);
926 
927 	if (en)
928 		IRQ_ON(host, SD_CONFIG_SI);
929 	else
930 		IRQ_OFF(host, SD_CONFIG_SI);
931 }
932 
933 static const struct mmc_host_ops au1xmmc_ops = {
934 	.request	= au1xmmc_request,
935 	.set_ios	= au1xmmc_set_ios,
936 	.get_ro		= au1xmmc_card_readonly,
937 	.get_cd		= au1xmmc_card_inserted,
938 	.enable_sdio_irq = au1xmmc_enable_sdio_irq,
939 };
940 
941 static int __devinit au1xmmc_probe(struct platform_device *pdev)
942 {
943 	struct mmc_host *mmc;
944 	struct au1xmmc_host *host;
945 	struct resource *r;
946 	int ret;
947 
948 	mmc = mmc_alloc_host(sizeof(struct au1xmmc_host), &pdev->dev);
949 	if (!mmc) {
950 		dev_err(&pdev->dev, "no memory for mmc_host\n");
951 		ret = -ENOMEM;
952 		goto out0;
953 	}
954 
955 	host = mmc_priv(mmc);
956 	host->mmc = mmc;
957 	host->platdata = pdev->dev.platform_data;
958 	host->pdev = pdev;
959 
960 	ret = -ENODEV;
961 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
962 	if (!r) {
963 		dev_err(&pdev->dev, "no mmio defined\n");
964 		goto out1;
965 	}
966 
967 	host->ioarea = request_mem_region(r->start, resource_size(r),
968 					   pdev->name);
969 	if (!host->ioarea) {
970 		dev_err(&pdev->dev, "mmio already in use\n");
971 		goto out1;
972 	}
973 
974 	host->iobase = (unsigned long)ioremap(r->start, 0x3c);
975 	if (!host->iobase) {
976 		dev_err(&pdev->dev, "cannot remap mmio\n");
977 		goto out2;
978 	}
979 
980 	r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
981 	if (!r) {
982 		dev_err(&pdev->dev, "no IRQ defined\n");
983 		goto out3;
984 	}
985 
986 	host->irq = r->start;
987 	/* IRQ is shared among both SD controllers */
988 	ret = request_irq(host->irq, au1xmmc_irq, IRQF_SHARED,
989 			  DRIVER_NAME, host);
990 	if (ret) {
991 		dev_err(&pdev->dev, "cannot grab IRQ\n");
992 		goto out3;
993 	}
994 
995 	mmc->ops = &au1xmmc_ops;
996 
997 	mmc->f_min =   450000;
998 	mmc->f_max = 24000000;
999 
1000 	switch (alchemy_get_cputype()) {
1001 	case ALCHEMY_CPU_AU1100:
1002 		mmc->max_seg_size = AU1100_MMC_DESCRIPTOR_SIZE;
1003 		mmc->max_segs = AU1XMMC_DESCRIPTOR_COUNT;
1004 		break;
1005 	case ALCHEMY_CPU_AU1200:
1006 		mmc->max_seg_size = AU1200_MMC_DESCRIPTOR_SIZE;
1007 		mmc->max_segs = AU1XMMC_DESCRIPTOR_COUNT;
1008 		break;
1009 	}
1010 
1011 	mmc->max_blk_size = 2048;
1012 	mmc->max_blk_count = 512;
1013 
1014 	mmc->ocr_avail = AU1XMMC_OCR;
1015 	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1016 
1017 	host->status = HOST_S_IDLE;
1018 
1019 	/* board-specific carddetect setup, if any */
1020 	if (host->platdata && host->platdata->cd_setup) {
1021 		ret = host->platdata->cd_setup(mmc, 1);
1022 		if (ret) {
1023 			dev_warn(&pdev->dev, "board CD setup failed\n");
1024 			mmc->caps |= MMC_CAP_NEEDS_POLL;
1025 		}
1026 	} else
1027 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1028 
1029 	/* platform may not be able to use all advertised caps */
1030 	if (host->platdata)
1031 		mmc->caps &= ~(host->platdata->mask_host_caps);
1032 
1033 	tasklet_init(&host->data_task, au1xmmc_tasklet_data,
1034 			(unsigned long)host);
1035 
1036 	tasklet_init(&host->finish_task, au1xmmc_tasklet_finish,
1037 			(unsigned long)host);
1038 
1039 	if (has_dbdma()) {
1040 		ret = au1xmmc_dbdma_init(host);
1041 		if (ret)
1042 			pr_info(DRIVER_NAME ": DBDMA init failed; using PIO\n");
1043 	}
1044 
1045 #ifdef CONFIG_LEDS_CLASS
1046 	if (host->platdata && host->platdata->led) {
1047 		struct led_classdev *led = host->platdata->led;
1048 		led->name = mmc_hostname(mmc);
1049 		led->brightness = LED_OFF;
1050 		led->default_trigger = mmc_hostname(mmc);
1051 		ret = led_classdev_register(mmc_dev(mmc), led);
1052 		if (ret)
1053 			goto out5;
1054 	}
1055 #endif
1056 
1057 	au1xmmc_reset_controller(host);
1058 
1059 	ret = mmc_add_host(mmc);
1060 	if (ret) {
1061 		dev_err(&pdev->dev, "cannot add mmc host\n");
1062 		goto out6;
1063 	}
1064 
1065 	platform_set_drvdata(pdev, host);
1066 
1067 	pr_info(DRIVER_NAME ": MMC Controller %d set up at %8.8X"
1068 		" (mode=%s)\n", pdev->id, host->iobase,
1069 		host->flags & HOST_F_DMA ? "dma" : "pio");
1070 
1071 	return 0;	/* all ok */
1072 
1073 out6:
1074 #ifdef CONFIG_LEDS_CLASS
1075 	if (host->platdata && host->platdata->led)
1076 		led_classdev_unregister(host->platdata->led);
1077 out5:
1078 #endif
1079 	au_writel(0, HOST_ENABLE(host));
1080 	au_writel(0, HOST_CONFIG(host));
1081 	au_writel(0, HOST_CONFIG2(host));
1082 	au_sync();
1083 
1084 	if (host->flags & HOST_F_DBDMA)
1085 		au1xmmc_dbdma_shutdown(host);
1086 
1087 	tasklet_kill(&host->data_task);
1088 	tasklet_kill(&host->finish_task);
1089 
1090 	if (host->platdata && host->platdata->cd_setup &&
1091 	    !(mmc->caps & MMC_CAP_NEEDS_POLL))
1092 		host->platdata->cd_setup(mmc, 0);
1093 
1094 	free_irq(host->irq, host);
1095 out3:
1096 	iounmap((void *)host->iobase);
1097 out2:
1098 	release_resource(host->ioarea);
1099 	kfree(host->ioarea);
1100 out1:
1101 	mmc_free_host(mmc);
1102 out0:
1103 	return ret;
1104 }
1105 
1106 static int __devexit au1xmmc_remove(struct platform_device *pdev)
1107 {
1108 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1109 
1110 	if (host) {
1111 		mmc_remove_host(host->mmc);
1112 
1113 #ifdef CONFIG_LEDS_CLASS
1114 		if (host->platdata && host->platdata->led)
1115 			led_classdev_unregister(host->platdata->led);
1116 #endif
1117 
1118 		if (host->platdata && host->platdata->cd_setup &&
1119 		    !(host->mmc->caps & MMC_CAP_NEEDS_POLL))
1120 			host->platdata->cd_setup(host->mmc, 0);
1121 
1122 		au_writel(0, HOST_ENABLE(host));
1123 		au_writel(0, HOST_CONFIG(host));
1124 		au_writel(0, HOST_CONFIG2(host));
1125 		au_sync();
1126 
1127 		tasklet_kill(&host->data_task);
1128 		tasklet_kill(&host->finish_task);
1129 
1130 		if (host->flags & HOST_F_DBDMA)
1131 			au1xmmc_dbdma_shutdown(host);
1132 
1133 		au1xmmc_set_power(host, 0);
1134 
1135 		free_irq(host->irq, host);
1136 		iounmap((void *)host->iobase);
1137 		release_resource(host->ioarea);
1138 		kfree(host->ioarea);
1139 
1140 		mmc_free_host(host->mmc);
1141 		platform_set_drvdata(pdev, NULL);
1142 	}
1143 	return 0;
1144 }
1145 
1146 #ifdef CONFIG_PM
1147 static int au1xmmc_suspend(struct platform_device *pdev, pm_message_t state)
1148 {
1149 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1150 	int ret;
1151 
1152 	ret = mmc_suspend_host(host->mmc);
1153 	if (ret)
1154 		return ret;
1155 
1156 	au_writel(0, HOST_CONFIG2(host));
1157 	au_writel(0, HOST_CONFIG(host));
1158 	au_writel(0xffffffff, HOST_STATUS(host));
1159 	au_writel(0, HOST_ENABLE(host));
1160 	au_sync();
1161 
1162 	return 0;
1163 }
1164 
1165 static int au1xmmc_resume(struct platform_device *pdev)
1166 {
1167 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1168 
1169 	au1xmmc_reset_controller(host);
1170 
1171 	return mmc_resume_host(host->mmc);
1172 }
1173 #else
1174 #define au1xmmc_suspend NULL
1175 #define au1xmmc_resume NULL
1176 #endif
1177 
1178 static struct platform_driver au1xmmc_driver = {
1179 	.probe         = au1xmmc_probe,
1180 	.remove        = au1xmmc_remove,
1181 	.suspend       = au1xmmc_suspend,
1182 	.resume        = au1xmmc_resume,
1183 	.driver        = {
1184 		.name  = DRIVER_NAME,
1185 		.owner = THIS_MODULE,
1186 	},
1187 };
1188 
1189 static int __init au1xmmc_init(void)
1190 {
1191 	if (has_dbdma()) {
1192 		/* DSCR_CMD0_ALWAYS has a stride of 32 bits, we need a stride
1193 		* of 8 bits.  And since devices are shared, we need to create
1194 		* our own to avoid freaking out other devices.
1195 		*/
1196 		memid = au1xxx_ddma_add_device(&au1xmmc_mem_dbdev);
1197 		if (!memid)
1198 			pr_err("au1xmmc: cannot add memory dbdma\n");
1199 	}
1200 	return platform_driver_register(&au1xmmc_driver);
1201 }
1202 
1203 static void __exit au1xmmc_exit(void)
1204 {
1205 	if (has_dbdma() && memid)
1206 		au1xxx_ddma_del_device(memid);
1207 
1208 	platform_driver_unregister(&au1xmmc_driver);
1209 }
1210 
1211 module_init(au1xmmc_init);
1212 module_exit(au1xmmc_exit);
1213 
1214 MODULE_AUTHOR("Advanced Micro Devices, Inc");
1215 MODULE_DESCRIPTION("MMC/SD driver for the Alchemy Au1XXX");
1216 MODULE_LICENSE("GPL");
1217 MODULE_ALIAS("platform:au1xxx-mmc");
1218