xref: /linux/drivers/mmc/host/au1xmmc.c (revision d53b8e36925256097a08d7cb749198d85cbf9b2b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * linux/drivers/mmc/host/au1xmmc.c - AU1XX0 MMC driver
4  *
5  *  Copyright (c) 2005, Advanced Micro Devices, Inc.
6  *
7  *  Developed with help from the 2.4.30 MMC AU1XXX controller including
8  *  the following copyright notices:
9  *     Copyright (c) 2003-2004 Embedded Edge, LLC.
10  *     Portions Copyright (C) 2002 Embedix, Inc
11  *     Copyright 2002 Hewlett-Packard Company
12 
13  *  2.6 version of this driver inspired by:
14  *     (drivers/mmc/wbsd.c) Copyright (C) 2004-2005 Pierre Ossman,
15  *     All Rights Reserved.
16  *     (drivers/mmc/pxa.c) Copyright (C) 2003 Russell King,
17  *     All Rights Reserved.
18  *
19 
20  */
21 
22 /* Why don't we use the SD controllers' carddetect feature?
23  *
24  * From the AU1100 MMC application guide:
25  * If the Au1100-based design is intended to support both MultiMediaCards
26  * and 1- or 4-data bit SecureDigital cards, then the solution is to
27  * connect a weak (560KOhm) pull-up resistor to connector pin 1.
28  * In doing so, a MMC card never enters SPI-mode communications,
29  * but now the SecureDigital card-detect feature of CD/DAT3 is ineffective
30  * (the low to high transition will not occur).
31  */
32 
33 #include <linux/clk.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/platform_device.h>
37 #include <linux/mm.h>
38 #include <linux/interrupt.h>
39 #include <linux/dma-mapping.h>
40 #include <linux/scatterlist.h>
41 #include <linux/highmem.h>
42 #include <linux/leds.h>
43 #include <linux/mmc/host.h>
44 #include <linux/slab.h>
45 #include <linux/workqueue.h>
46 
47 #include <asm/io.h>
48 #include <asm/mach-au1x00/au1000.h>
49 #include <asm/mach-au1x00/au1xxx_dbdma.h>
50 #include <asm/mach-au1x00/au1100_mmc.h>
51 
52 #define DRIVER_NAME "au1xxx-mmc"
53 
54 /* Set this to enable special debugging macros */
55 /* #define DEBUG */
56 
57 #ifdef DEBUG
58 #define DBG(fmt, idx, args...)	\
59 	pr_debug("au1xmmc(%d): DEBUG: " fmt, idx, ##args)
60 #else
61 #define DBG(fmt, idx, args...) do {} while (0)
62 #endif
63 
64 /* Hardware definitions */
65 #define AU1XMMC_DESCRIPTOR_COUNT 1
66 
67 /* max DMA seg size: 64KB on Au1100, 4MB on Au1200 */
68 #define AU1100_MMC_DESCRIPTOR_SIZE 0x0000ffff
69 #define AU1200_MMC_DESCRIPTOR_SIZE 0x003fffff
70 
71 #define AU1XMMC_OCR (MMC_VDD_27_28 | MMC_VDD_28_29 | MMC_VDD_29_30 | \
72 		     MMC_VDD_30_31 | MMC_VDD_31_32 | MMC_VDD_32_33 | \
73 		     MMC_VDD_33_34 | MMC_VDD_34_35 | MMC_VDD_35_36)
74 
75 /* This gives us a hard value for the stop command that we can write directly
76  * to the command register.
77  */
78 #define STOP_CMD	\
79 	(SD_CMD_RT_1B | SD_CMD_CT_7 | (0xC << SD_CMD_CI_SHIFT) | SD_CMD_GO)
80 
81 /* This is the set of interrupts that we configure by default. */
82 #define AU1XMMC_INTERRUPTS 				\
83 	(SD_CONFIG_SC | SD_CONFIG_DT | SD_CONFIG_RAT |	\
84 	 SD_CONFIG_CR | SD_CONFIG_I)
85 
86 /* The poll event (looking for insert/remove events runs twice a second. */
87 #define AU1XMMC_DETECT_TIMEOUT (HZ/2)
88 
89 struct au1xmmc_host {
90 	struct mmc_host *mmc;
91 	struct mmc_request *mrq;
92 
93 	u32 flags;
94 	void __iomem *iobase;
95 	u32 clock;
96 	u32 bus_width;
97 	u32 power_mode;
98 
99 	int status;
100 
101 	struct {
102 		int len;
103 		int dir;
104 	} dma;
105 
106 	struct {
107 		int index;
108 		int offset;
109 		int len;
110 	} pio;
111 
112 	u32 tx_chan;
113 	u32 rx_chan;
114 
115 	int irq;
116 
117 	struct work_struct finish_bh_work;
118 	struct work_struct data_bh_work;
119 	struct au1xmmc_platform_data *platdata;
120 	struct platform_device *pdev;
121 	struct resource *ioarea;
122 	struct clk *clk;
123 };
124 
125 /* Status flags used by the host structure */
126 #define HOST_F_XMIT	0x0001
127 #define HOST_F_RECV	0x0002
128 #define HOST_F_DMA	0x0010
129 #define HOST_F_DBDMA	0x0020
130 #define HOST_F_ACTIVE	0x0100
131 #define HOST_F_STOP	0x1000
132 
133 #define HOST_S_IDLE	0x0001
134 #define HOST_S_CMD	0x0002
135 #define HOST_S_DATA	0x0003
136 #define HOST_S_STOP	0x0004
137 
138 /* Easy access macros */
139 #define HOST_STATUS(h)	((h)->iobase + SD_STATUS)
140 #define HOST_CONFIG(h)	((h)->iobase + SD_CONFIG)
141 #define HOST_ENABLE(h)	((h)->iobase + SD_ENABLE)
142 #define HOST_TXPORT(h)	((h)->iobase + SD_TXPORT)
143 #define HOST_RXPORT(h)	((h)->iobase + SD_RXPORT)
144 #define HOST_CMDARG(h)	((h)->iobase + SD_CMDARG)
145 #define HOST_BLKSIZE(h)	((h)->iobase + SD_BLKSIZE)
146 #define HOST_CMD(h)	((h)->iobase + SD_CMD)
147 #define HOST_CONFIG2(h)	((h)->iobase + SD_CONFIG2)
148 #define HOST_TIMEOUT(h)	((h)->iobase + SD_TIMEOUT)
149 #define HOST_DEBUG(h)	((h)->iobase + SD_DEBUG)
150 
151 #define DMA_CHANNEL(h)	\
152 	(((h)->flags & HOST_F_XMIT) ? (h)->tx_chan : (h)->rx_chan)
153 
154 static inline int has_dbdma(void)
155 {
156 	switch (alchemy_get_cputype()) {
157 	case ALCHEMY_CPU_AU1200:
158 	case ALCHEMY_CPU_AU1300:
159 		return 1;
160 	default:
161 		return 0;
162 	}
163 }
164 
165 static inline void IRQ_ON(struct au1xmmc_host *host, u32 mask)
166 {
167 	u32 val = __raw_readl(HOST_CONFIG(host));
168 	val |= mask;
169 	__raw_writel(val, HOST_CONFIG(host));
170 	wmb(); /* drain writebuffer */
171 }
172 
173 static inline void FLUSH_FIFO(struct au1xmmc_host *host)
174 {
175 	u32 val = __raw_readl(HOST_CONFIG2(host));
176 
177 	__raw_writel(val | SD_CONFIG2_FF, HOST_CONFIG2(host));
178 	wmb(); /* drain writebuffer */
179 	mdelay(1);
180 
181 	/* SEND_STOP will turn off clock control - this re-enables it */
182 	val &= ~SD_CONFIG2_DF;
183 
184 	__raw_writel(val, HOST_CONFIG2(host));
185 	wmb(); /* drain writebuffer */
186 }
187 
188 static inline void IRQ_OFF(struct au1xmmc_host *host, u32 mask)
189 {
190 	u32 val = __raw_readl(HOST_CONFIG(host));
191 	val &= ~mask;
192 	__raw_writel(val, HOST_CONFIG(host));
193 	wmb(); /* drain writebuffer */
194 }
195 
196 static inline void SEND_STOP(struct au1xmmc_host *host)
197 {
198 	u32 config2;
199 
200 	WARN_ON(host->status != HOST_S_DATA);
201 	host->status = HOST_S_STOP;
202 
203 	config2 = __raw_readl(HOST_CONFIG2(host));
204 	__raw_writel(config2 | SD_CONFIG2_DF, HOST_CONFIG2(host));
205 	wmb(); /* drain writebuffer */
206 
207 	/* Send the stop command */
208 	__raw_writel(STOP_CMD, HOST_CMD(host));
209 	wmb(); /* drain writebuffer */
210 }
211 
212 static void au1xmmc_set_power(struct au1xmmc_host *host, int state)
213 {
214 	if (host->platdata && host->platdata->set_power)
215 		host->platdata->set_power(host->mmc, state);
216 }
217 
218 static int au1xmmc_card_inserted(struct mmc_host *mmc)
219 {
220 	struct au1xmmc_host *host = mmc_priv(mmc);
221 
222 	if (host->platdata && host->platdata->card_inserted)
223 		return !!host->platdata->card_inserted(host->mmc);
224 
225 	return -ENOSYS;
226 }
227 
228 static int au1xmmc_card_readonly(struct mmc_host *mmc)
229 {
230 	struct au1xmmc_host *host = mmc_priv(mmc);
231 
232 	if (host->platdata && host->platdata->card_readonly)
233 		return !!host->platdata->card_readonly(mmc);
234 
235 	return -ENOSYS;
236 }
237 
238 static void au1xmmc_finish_request(struct au1xmmc_host *host)
239 {
240 	struct mmc_request *mrq = host->mrq;
241 
242 	host->mrq = NULL;
243 	host->flags &= HOST_F_ACTIVE | HOST_F_DMA;
244 
245 	host->dma.len = 0;
246 	host->dma.dir = 0;
247 
248 	host->pio.index  = 0;
249 	host->pio.offset = 0;
250 	host->pio.len = 0;
251 
252 	host->status = HOST_S_IDLE;
253 
254 	mmc_request_done(host->mmc, mrq);
255 }
256 
257 static void au1xmmc_finish_bh_work(struct work_struct *t)
258 {
259 	struct au1xmmc_host *host = from_work(host, t, finish_bh_work);
260 	au1xmmc_finish_request(host);
261 }
262 
263 static int au1xmmc_send_command(struct au1xmmc_host *host,
264 				struct mmc_command *cmd, struct mmc_data *data)
265 {
266 	u32 mmccmd = (cmd->opcode << SD_CMD_CI_SHIFT);
267 
268 	switch (mmc_resp_type(cmd)) {
269 	case MMC_RSP_NONE:
270 		break;
271 	case MMC_RSP_R1:
272 		mmccmd |= SD_CMD_RT_1;
273 		break;
274 	case MMC_RSP_R1B:
275 		mmccmd |= SD_CMD_RT_1B;
276 		break;
277 	case MMC_RSP_R2:
278 		mmccmd |= SD_CMD_RT_2;
279 		break;
280 	case MMC_RSP_R3:
281 		mmccmd |= SD_CMD_RT_3;
282 		break;
283 	default:
284 		pr_info("au1xmmc: unhandled response type %02x\n",
285 			mmc_resp_type(cmd));
286 		return -EINVAL;
287 	}
288 
289 	if (data) {
290 		if (data->flags & MMC_DATA_READ) {
291 			if (data->blocks > 1)
292 				mmccmd |= SD_CMD_CT_4;
293 			else
294 				mmccmd |= SD_CMD_CT_2;
295 		} else if (data->flags & MMC_DATA_WRITE) {
296 			if (data->blocks > 1)
297 				mmccmd |= SD_CMD_CT_3;
298 			else
299 				mmccmd |= SD_CMD_CT_1;
300 		}
301 	}
302 
303 	__raw_writel(cmd->arg, HOST_CMDARG(host));
304 	wmb(); /* drain writebuffer */
305 
306 	__raw_writel((mmccmd | SD_CMD_GO), HOST_CMD(host));
307 	wmb(); /* drain writebuffer */
308 
309 	/* Wait for the command to go on the line */
310 	while (__raw_readl(HOST_CMD(host)) & SD_CMD_GO)
311 		/* nop */;
312 
313 	return 0;
314 }
315 
316 static void au1xmmc_data_complete(struct au1xmmc_host *host, u32 status)
317 {
318 	struct mmc_request *mrq = host->mrq;
319 	struct mmc_data *data;
320 	u32 crc;
321 
322 	WARN_ON((host->status != HOST_S_DATA) && (host->status != HOST_S_STOP));
323 
324 	if (host->mrq == NULL)
325 		return;
326 
327 	data = mrq->cmd->data;
328 
329 	if (status == 0)
330 		status = __raw_readl(HOST_STATUS(host));
331 
332 	/* The transaction is really over when the SD_STATUS_DB bit is clear */
333 	while ((host->flags & HOST_F_XMIT) && (status & SD_STATUS_DB))
334 		status = __raw_readl(HOST_STATUS(host));
335 
336 	data->error = 0;
337 	dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len, host->dma.dir);
338 
339         /* Process any errors */
340 	crc = (status & (SD_STATUS_WC | SD_STATUS_RC));
341 	if (host->flags & HOST_F_XMIT)
342 		crc |= ((status & 0x07) == 0x02) ? 0 : 1;
343 
344 	if (crc)
345 		data->error = -EILSEQ;
346 
347 	/* Clear the CRC bits */
348 	__raw_writel(SD_STATUS_WC | SD_STATUS_RC, HOST_STATUS(host));
349 
350 	data->bytes_xfered = 0;
351 
352 	if (!data->error) {
353 		if (host->flags & (HOST_F_DMA | HOST_F_DBDMA)) {
354 			u32 chan = DMA_CHANNEL(host);
355 
356 			chan_tab_t *c = *((chan_tab_t **)chan);
357 			au1x_dma_chan_t *cp = c->chan_ptr;
358 			data->bytes_xfered = cp->ddma_bytecnt;
359 		} else
360 			data->bytes_xfered =
361 				(data->blocks * data->blksz) - host->pio.len;
362 	}
363 
364 	au1xmmc_finish_request(host);
365 }
366 
367 static void au1xmmc_data_bh_work(struct work_struct *t)
368 {
369 	struct au1xmmc_host *host = from_work(host, t, data_bh_work);
370 
371 	u32 status = __raw_readl(HOST_STATUS(host));
372 	au1xmmc_data_complete(host, status);
373 }
374 
375 #define AU1XMMC_MAX_TRANSFER 8
376 
377 static void au1xmmc_send_pio(struct au1xmmc_host *host)
378 {
379 	struct mmc_data *data;
380 	int sg_len, max, count;
381 	unsigned char *sg_ptr, val;
382 	u32 status;
383 	struct scatterlist *sg;
384 
385 	data = host->mrq->data;
386 
387 	if (!(host->flags & HOST_F_XMIT))
388 		return;
389 
390 	/* This is the pointer to the data buffer */
391 	sg = &data->sg[host->pio.index];
392 	sg_ptr = kmap_local_page(sg_page(sg)) + sg->offset + host->pio.offset;
393 
394 	/* This is the space left inside the buffer */
395 	sg_len = data->sg[host->pio.index].length - host->pio.offset;
396 
397 	/* Check if we need less than the size of the sg_buffer */
398 	max = (sg_len > host->pio.len) ? host->pio.len : sg_len;
399 	if (max > AU1XMMC_MAX_TRANSFER)
400 		max = AU1XMMC_MAX_TRANSFER;
401 
402 	for (count = 0; count < max; count++) {
403 		status = __raw_readl(HOST_STATUS(host));
404 
405 		if (!(status & SD_STATUS_TH))
406 			break;
407 
408 		val = sg_ptr[count];
409 
410 		__raw_writel((unsigned long)val, HOST_TXPORT(host));
411 		wmb(); /* drain writebuffer */
412 	}
413 	kunmap_local(sg_ptr);
414 
415 	host->pio.len -= count;
416 	host->pio.offset += count;
417 
418 	if (count == sg_len) {
419 		host->pio.index++;
420 		host->pio.offset = 0;
421 	}
422 
423 	if (host->pio.len == 0) {
424 		IRQ_OFF(host, SD_CONFIG_TH);
425 
426 		if (host->flags & HOST_F_STOP)
427 			SEND_STOP(host);
428 
429 		queue_work(system_bh_wq, &host->data_bh_work);
430 	}
431 }
432 
433 static void au1xmmc_receive_pio(struct au1xmmc_host *host)
434 {
435 	struct mmc_data *data;
436 	int max, count, sg_len = 0;
437 	unsigned char *sg_ptr = NULL;
438 	u32 status, val;
439 	struct scatterlist *sg;
440 
441 	data = host->mrq->data;
442 
443 	if (!(host->flags & HOST_F_RECV))
444 		return;
445 
446 	max = host->pio.len;
447 
448 	if (host->pio.index < host->dma.len) {
449 		sg = &data->sg[host->pio.index];
450 		sg_ptr = kmap_local_page(sg_page(sg)) + sg->offset + host->pio.offset;
451 
452 		/* This is the space left inside the buffer */
453 		sg_len = sg_dma_len(&data->sg[host->pio.index]) - host->pio.offset;
454 
455 		/* Check if we need less than the size of the sg_buffer */
456 		if (sg_len < max)
457 			max = sg_len;
458 	}
459 
460 	if (max > AU1XMMC_MAX_TRANSFER)
461 		max = AU1XMMC_MAX_TRANSFER;
462 
463 	for (count = 0; count < max; count++) {
464 		status = __raw_readl(HOST_STATUS(host));
465 
466 		if (!(status & SD_STATUS_NE))
467 			break;
468 
469 		if (status & SD_STATUS_RC) {
470 			DBG("RX CRC Error [%d + %d].\n", host->pdev->id,
471 					host->pio.len, count);
472 			break;
473 		}
474 
475 		if (status & SD_STATUS_RO) {
476 			DBG("RX Overrun [%d + %d]\n", host->pdev->id,
477 					host->pio.len, count);
478 			break;
479 		}
480 		else if (status & SD_STATUS_RU) {
481 			DBG("RX Underrun [%d + %d]\n", host->pdev->id,
482 					host->pio.len,	count);
483 			break;
484 		}
485 
486 		val = __raw_readl(HOST_RXPORT(host));
487 
488 		if (sg_ptr)
489 			sg_ptr[count] = (unsigned char)(val & 0xFF);
490 	}
491 	if (sg_ptr)
492 		kunmap_local(sg_ptr);
493 
494 	host->pio.len -= count;
495 	host->pio.offset += count;
496 
497 	if (sg_len && count == sg_len) {
498 		host->pio.index++;
499 		host->pio.offset = 0;
500 	}
501 
502 	if (host->pio.len == 0) {
503 		/* IRQ_OFF(host, SD_CONFIG_RA | SD_CONFIG_RF); */
504 		IRQ_OFF(host, SD_CONFIG_NE);
505 
506 		if (host->flags & HOST_F_STOP)
507 			SEND_STOP(host);
508 
509 		queue_work(system_bh_wq, &host->data_bh_work);
510 	}
511 }
512 
513 /* This is called when a command has been completed - grab the response
514  * and check for errors.  Then start the data transfer if it is indicated.
515  */
516 static void au1xmmc_cmd_complete(struct au1xmmc_host *host, u32 status)
517 {
518 	struct mmc_request *mrq = host->mrq;
519 	struct mmc_command *cmd;
520 	u32 r[4];
521 	int i, trans;
522 
523 	if (!host->mrq)
524 		return;
525 
526 	cmd = mrq->cmd;
527 	cmd->error = 0;
528 
529 	if (cmd->flags & MMC_RSP_PRESENT) {
530 		if (cmd->flags & MMC_RSP_136) {
531 			r[0] = __raw_readl(host->iobase + SD_RESP3);
532 			r[1] = __raw_readl(host->iobase + SD_RESP2);
533 			r[2] = __raw_readl(host->iobase + SD_RESP1);
534 			r[3] = __raw_readl(host->iobase + SD_RESP0);
535 
536 			/* The CRC is omitted from the response, so really
537 			 * we only got 120 bytes, but the engine expects
538 			 * 128 bits, so we have to shift things up.
539 			 */
540 			for (i = 0; i < 4; i++) {
541 				cmd->resp[i] = (r[i] & 0x00FFFFFF) << 8;
542 				if (i != 3)
543 					cmd->resp[i] |= (r[i + 1] & 0xFF000000) >> 24;
544 			}
545 		} else {
546 			/* Techincally, we should be getting all 48 bits of
547 			 * the response (SD_RESP1 + SD_RESP2), but because
548 			 * our response omits the CRC, our data ends up
549 			 * being shifted 8 bits to the right.  In this case,
550 			 * that means that the OSR data starts at bit 31,
551 			 * so we can just read RESP0 and return that.
552 			 */
553 			cmd->resp[0] = __raw_readl(host->iobase + SD_RESP0);
554 		}
555 	}
556 
557         /* Figure out errors */
558 	if (status & (SD_STATUS_SC | SD_STATUS_WC | SD_STATUS_RC))
559 		cmd->error = -EILSEQ;
560 
561 	trans = host->flags & (HOST_F_XMIT | HOST_F_RECV);
562 
563 	if (!trans || cmd->error) {
564 		IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF);
565 		queue_work(system_bh_wq, &host->finish_bh_work);
566 		return;
567 	}
568 
569 	host->status = HOST_S_DATA;
570 
571 	if ((host->flags & (HOST_F_DMA | HOST_F_DBDMA))) {
572 		u32 channel = DMA_CHANNEL(host);
573 
574 		/* Start the DBDMA as soon as the buffer gets something in it */
575 
576 		if (host->flags & HOST_F_RECV) {
577 			u32 mask = SD_STATUS_DB | SD_STATUS_NE;
578 
579 			while((status & mask) != mask)
580 				status = __raw_readl(HOST_STATUS(host));
581 		}
582 
583 		au1xxx_dbdma_start(channel);
584 	}
585 }
586 
587 static void au1xmmc_set_clock(struct au1xmmc_host *host, int rate)
588 {
589 	unsigned int pbus = clk_get_rate(host->clk);
590 	unsigned int divisor = ((pbus / rate) / 2) - 1;
591 	u32 config;
592 
593 	config = __raw_readl(HOST_CONFIG(host));
594 
595 	config &= ~(SD_CONFIG_DIV);
596 	config |= (divisor & SD_CONFIG_DIV) | SD_CONFIG_DE;
597 
598 	__raw_writel(config, HOST_CONFIG(host));
599 	wmb(); /* drain writebuffer */
600 }
601 
602 static int au1xmmc_prepare_data(struct au1xmmc_host *host,
603 				struct mmc_data *data)
604 {
605 	int datalen = data->blocks * data->blksz;
606 
607 	if (data->flags & MMC_DATA_READ)
608 		host->flags |= HOST_F_RECV;
609 	else
610 		host->flags |= HOST_F_XMIT;
611 
612 	if (host->mrq->stop)
613 		host->flags |= HOST_F_STOP;
614 
615 	host->dma.dir = DMA_BIDIRECTIONAL;
616 
617 	host->dma.len = dma_map_sg(mmc_dev(host->mmc), data->sg,
618 				   data->sg_len, host->dma.dir);
619 
620 	if (host->dma.len == 0)
621 		return -ETIMEDOUT;
622 
623 	__raw_writel(data->blksz - 1, HOST_BLKSIZE(host));
624 
625 	if (host->flags & (HOST_F_DMA | HOST_F_DBDMA)) {
626 		int i;
627 		u32 channel = DMA_CHANNEL(host);
628 
629 		au1xxx_dbdma_stop(channel);
630 
631 		for (i = 0; i < host->dma.len; i++) {
632 			u32 ret = 0, flags = DDMA_FLAGS_NOIE;
633 			struct scatterlist *sg = &data->sg[i];
634 			int sg_len = sg->length;
635 
636 			int len = (datalen > sg_len) ? sg_len : datalen;
637 
638 			if (i == host->dma.len - 1)
639 				flags = DDMA_FLAGS_IE;
640 
641 			if (host->flags & HOST_F_XMIT) {
642 				ret = au1xxx_dbdma_put_source(channel,
643 					sg_phys(sg), len, flags);
644 			} else {
645 				ret = au1xxx_dbdma_put_dest(channel,
646 					sg_phys(sg), len, flags);
647 			}
648 
649 			if (!ret)
650 				goto dataerr;
651 
652 			datalen -= len;
653 		}
654 	} else {
655 		host->pio.index = 0;
656 		host->pio.offset = 0;
657 		host->pio.len = datalen;
658 
659 		if (host->flags & HOST_F_XMIT)
660 			IRQ_ON(host, SD_CONFIG_TH);
661 		else
662 			IRQ_ON(host, SD_CONFIG_NE);
663 			/* IRQ_ON(host, SD_CONFIG_RA | SD_CONFIG_RF); */
664 	}
665 
666 	return 0;
667 
668 dataerr:
669 	dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
670 			host->dma.dir);
671 	return -ETIMEDOUT;
672 }
673 
674 /* This actually starts a command or data transaction */
675 static void au1xmmc_request(struct mmc_host* mmc, struct mmc_request* mrq)
676 {
677 	struct au1xmmc_host *host = mmc_priv(mmc);
678 	int ret = 0;
679 
680 	WARN_ON(irqs_disabled());
681 	WARN_ON(host->status != HOST_S_IDLE);
682 
683 	host->mrq = mrq;
684 	host->status = HOST_S_CMD;
685 
686 	/* fail request immediately if no card is present */
687 	if (0 == au1xmmc_card_inserted(mmc)) {
688 		mrq->cmd->error = -ENOMEDIUM;
689 		au1xmmc_finish_request(host);
690 		return;
691 	}
692 
693 	if (mrq->data) {
694 		FLUSH_FIFO(host);
695 		ret = au1xmmc_prepare_data(host, mrq->data);
696 	}
697 
698 	if (!ret)
699 		ret = au1xmmc_send_command(host, mrq->cmd, mrq->data);
700 
701 	if (ret) {
702 		mrq->cmd->error = ret;
703 		au1xmmc_finish_request(host);
704 	}
705 }
706 
707 static void au1xmmc_reset_controller(struct au1xmmc_host *host)
708 {
709 	/* Apply the clock */
710 	__raw_writel(SD_ENABLE_CE, HOST_ENABLE(host));
711 	wmb(); /* drain writebuffer */
712 	mdelay(1);
713 
714 	__raw_writel(SD_ENABLE_R | SD_ENABLE_CE, HOST_ENABLE(host));
715 	wmb(); /* drain writebuffer */
716 	mdelay(5);
717 
718 	__raw_writel(~0, HOST_STATUS(host));
719 	wmb(); /* drain writebuffer */
720 
721 	__raw_writel(0, HOST_BLKSIZE(host));
722 	__raw_writel(0x001fffff, HOST_TIMEOUT(host));
723 	wmb(); /* drain writebuffer */
724 
725 	__raw_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
726 	wmb(); /* drain writebuffer */
727 
728 	__raw_writel(SD_CONFIG2_EN | SD_CONFIG2_FF, HOST_CONFIG2(host));
729 	wmb(); /* drain writebuffer */
730 	mdelay(1);
731 
732 	__raw_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
733 	wmb(); /* drain writebuffer */
734 
735 	/* Configure interrupts */
736 	__raw_writel(AU1XMMC_INTERRUPTS, HOST_CONFIG(host));
737 	wmb(); /* drain writebuffer */
738 }
739 
740 
741 static void au1xmmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
742 {
743 	struct au1xmmc_host *host = mmc_priv(mmc);
744 	u32 config2;
745 
746 	if (ios->power_mode == MMC_POWER_OFF)
747 		au1xmmc_set_power(host, 0);
748 	else if (ios->power_mode == MMC_POWER_ON) {
749 		au1xmmc_set_power(host, 1);
750 	}
751 
752 	if (ios->clock && ios->clock != host->clock) {
753 		au1xmmc_set_clock(host, ios->clock);
754 		host->clock = ios->clock;
755 	}
756 
757 	config2 = __raw_readl(HOST_CONFIG2(host));
758 	switch (ios->bus_width) {
759 	case MMC_BUS_WIDTH_8:
760 		config2 |= SD_CONFIG2_BB;
761 		break;
762 	case MMC_BUS_WIDTH_4:
763 		config2 &= ~SD_CONFIG2_BB;
764 		config2 |= SD_CONFIG2_WB;
765 		break;
766 	case MMC_BUS_WIDTH_1:
767 		config2 &= ~(SD_CONFIG2_WB | SD_CONFIG2_BB);
768 		break;
769 	}
770 	__raw_writel(config2, HOST_CONFIG2(host));
771 	wmb(); /* drain writebuffer */
772 }
773 
774 #define STATUS_TIMEOUT (SD_STATUS_RAT | SD_STATUS_DT)
775 #define STATUS_DATA_IN  (SD_STATUS_NE)
776 #define STATUS_DATA_OUT (SD_STATUS_TH)
777 
778 static irqreturn_t au1xmmc_irq(int irq, void *dev_id)
779 {
780 	struct au1xmmc_host *host = dev_id;
781 	u32 status;
782 
783 	status = __raw_readl(HOST_STATUS(host));
784 
785 	if (!(status & SD_STATUS_I))
786 		return IRQ_NONE;	/* not ours */
787 
788 	if (status & SD_STATUS_SI)	/* SDIO */
789 		mmc_signal_sdio_irq(host->mmc);
790 
791 	if (host->mrq && (status & STATUS_TIMEOUT)) {
792 		if (status & SD_STATUS_RAT)
793 			host->mrq->cmd->error = -ETIMEDOUT;
794 		else if (status & SD_STATUS_DT)
795 			host->mrq->data->error = -ETIMEDOUT;
796 
797 		/* In PIO mode, interrupts might still be enabled */
798 		IRQ_OFF(host, SD_CONFIG_NE | SD_CONFIG_TH);
799 
800 		/* IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF); */
801 		queue_work(system_bh_wq, &host->finish_bh_work);
802 	}
803 #if 0
804 	else if (status & SD_STATUS_DD) {
805 		/* Sometimes we get a DD before a NE in PIO mode */
806 		if (!(host->flags & HOST_F_DMA) && (status & SD_STATUS_NE))
807 			au1xmmc_receive_pio(host);
808 		else {
809 			au1xmmc_data_complete(host, status);
810 			/* queue_work(system_bh_wq, &host->data_bh_work); */
811 		}
812 	}
813 #endif
814 	else if (status & SD_STATUS_CR) {
815 		if (host->status == HOST_S_CMD)
816 			au1xmmc_cmd_complete(host, status);
817 
818 	} else if (!(host->flags & HOST_F_DMA)) {
819 		if ((host->flags & HOST_F_XMIT) && (status & STATUS_DATA_OUT))
820 			au1xmmc_send_pio(host);
821 		else if ((host->flags & HOST_F_RECV) && (status & STATUS_DATA_IN))
822 			au1xmmc_receive_pio(host);
823 
824 	} else if (status & 0x203F3C70) {
825 			DBG("Unhandled status %8.8x\n", host->pdev->id,
826 				status);
827 	}
828 
829 	__raw_writel(status, HOST_STATUS(host));
830 	wmb(); /* drain writebuffer */
831 
832 	return IRQ_HANDLED;
833 }
834 
835 /* 8bit memory DMA device */
836 static dbdev_tab_t au1xmmc_mem_dbdev = {
837 	.dev_id		= DSCR_CMD0_ALWAYS,
838 	.dev_flags	= DEV_FLAGS_ANYUSE,
839 	.dev_tsize	= 0,
840 	.dev_devwidth	= 8,
841 	.dev_physaddr	= 0x00000000,
842 	.dev_intlevel	= 0,
843 	.dev_intpolarity = 0,
844 };
845 static int memid;
846 
847 static void au1xmmc_dbdma_callback(int irq, void *dev_id)
848 {
849 	struct au1xmmc_host *host = (struct au1xmmc_host *)dev_id;
850 
851 	/* Avoid spurious interrupts */
852 	if (!host->mrq)
853 		return;
854 
855 	if (host->flags & HOST_F_STOP)
856 		SEND_STOP(host);
857 
858 	queue_work(system_bh_wq, &host->data_bh_work);
859 }
860 
861 static int au1xmmc_dbdma_init(struct au1xmmc_host *host)
862 {
863 	struct resource *res;
864 	int txid, rxid;
865 
866 	res = platform_get_resource(host->pdev, IORESOURCE_DMA, 0);
867 	if (!res)
868 		return -ENODEV;
869 	txid = res->start;
870 
871 	res = platform_get_resource(host->pdev, IORESOURCE_DMA, 1);
872 	if (!res)
873 		return -ENODEV;
874 	rxid = res->start;
875 
876 	if (!memid)
877 		return -ENODEV;
878 
879 	host->tx_chan = au1xxx_dbdma_chan_alloc(memid, txid,
880 				au1xmmc_dbdma_callback, (void *)host);
881 	if (!host->tx_chan) {
882 		dev_err(&host->pdev->dev, "cannot allocate TX DMA\n");
883 		return -ENODEV;
884 	}
885 
886 	host->rx_chan = au1xxx_dbdma_chan_alloc(rxid, memid,
887 				au1xmmc_dbdma_callback, (void *)host);
888 	if (!host->rx_chan) {
889 		dev_err(&host->pdev->dev, "cannot allocate RX DMA\n");
890 		au1xxx_dbdma_chan_free(host->tx_chan);
891 		return -ENODEV;
892 	}
893 
894 	au1xxx_dbdma_set_devwidth(host->tx_chan, 8);
895 	au1xxx_dbdma_set_devwidth(host->rx_chan, 8);
896 
897 	au1xxx_dbdma_ring_alloc(host->tx_chan, AU1XMMC_DESCRIPTOR_COUNT);
898 	au1xxx_dbdma_ring_alloc(host->rx_chan, AU1XMMC_DESCRIPTOR_COUNT);
899 
900 	/* DBDMA is good to go */
901 	host->flags |= HOST_F_DMA | HOST_F_DBDMA;
902 
903 	return 0;
904 }
905 
906 static void au1xmmc_dbdma_shutdown(struct au1xmmc_host *host)
907 {
908 	if (host->flags & HOST_F_DMA) {
909 		host->flags &= ~HOST_F_DMA;
910 		au1xxx_dbdma_chan_free(host->tx_chan);
911 		au1xxx_dbdma_chan_free(host->rx_chan);
912 	}
913 }
914 
915 static void au1xmmc_enable_sdio_irq(struct mmc_host *mmc, int en)
916 {
917 	struct au1xmmc_host *host = mmc_priv(mmc);
918 
919 	if (en)
920 		IRQ_ON(host, SD_CONFIG_SI);
921 	else
922 		IRQ_OFF(host, SD_CONFIG_SI);
923 }
924 
925 static const struct mmc_host_ops au1xmmc_ops = {
926 	.request	= au1xmmc_request,
927 	.set_ios	= au1xmmc_set_ios,
928 	.get_ro		= au1xmmc_card_readonly,
929 	.get_cd		= au1xmmc_card_inserted,
930 	.enable_sdio_irq = au1xmmc_enable_sdio_irq,
931 };
932 
933 static int au1xmmc_probe(struct platform_device *pdev)
934 {
935 	struct mmc_host *mmc;
936 	struct au1xmmc_host *host;
937 	struct resource *r;
938 	int ret, iflag;
939 
940 	mmc = mmc_alloc_host(sizeof(struct au1xmmc_host), &pdev->dev);
941 	if (!mmc) {
942 		dev_err(&pdev->dev, "no memory for mmc_host\n");
943 		ret = -ENOMEM;
944 		goto out0;
945 	}
946 
947 	host = mmc_priv(mmc);
948 	host->mmc = mmc;
949 	host->platdata = pdev->dev.platform_data;
950 	host->pdev = pdev;
951 
952 	ret = -ENODEV;
953 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
954 	if (!r) {
955 		dev_err(&pdev->dev, "no mmio defined\n");
956 		goto out1;
957 	}
958 
959 	host->ioarea = request_mem_region(r->start, resource_size(r),
960 					   pdev->name);
961 	if (!host->ioarea) {
962 		dev_err(&pdev->dev, "mmio already in use\n");
963 		goto out1;
964 	}
965 
966 	host->iobase = ioremap(r->start, 0x3c);
967 	if (!host->iobase) {
968 		dev_err(&pdev->dev, "cannot remap mmio\n");
969 		goto out2;
970 	}
971 
972 	host->irq = platform_get_irq(pdev, 0);
973 	if (host->irq < 0) {
974 		ret = host->irq;
975 		goto out3;
976 	}
977 
978 	mmc->ops = &au1xmmc_ops;
979 
980 	mmc->f_min =   450000;
981 	mmc->f_max = 24000000;
982 
983 	mmc->max_blk_size = 2048;
984 	mmc->max_blk_count = 512;
985 
986 	mmc->ocr_avail = AU1XMMC_OCR;
987 	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
988 	mmc->max_segs = AU1XMMC_DESCRIPTOR_COUNT;
989 
990 	iflag = IRQF_SHARED;	/* Au1100/Au1200: one int for both ctrls */
991 
992 	switch (alchemy_get_cputype()) {
993 	case ALCHEMY_CPU_AU1100:
994 		mmc->max_seg_size = AU1100_MMC_DESCRIPTOR_SIZE;
995 		break;
996 	case ALCHEMY_CPU_AU1200:
997 		mmc->max_seg_size = AU1200_MMC_DESCRIPTOR_SIZE;
998 		break;
999 	case ALCHEMY_CPU_AU1300:
1000 		iflag = 0;	/* nothing is shared */
1001 		mmc->max_seg_size = AU1200_MMC_DESCRIPTOR_SIZE;
1002 		mmc->f_max = 52000000;
1003 		if (host->ioarea->start == AU1100_SD0_PHYS_ADDR)
1004 			mmc->caps |= MMC_CAP_8_BIT_DATA;
1005 		break;
1006 	}
1007 
1008 	ret = request_irq(host->irq, au1xmmc_irq, iflag, DRIVER_NAME, host);
1009 	if (ret) {
1010 		dev_err(&pdev->dev, "cannot grab IRQ\n");
1011 		goto out3;
1012 	}
1013 
1014 	host->clk = clk_get(&pdev->dev, ALCHEMY_PERIPH_CLK);
1015 	if (IS_ERR(host->clk)) {
1016 		dev_err(&pdev->dev, "cannot find clock\n");
1017 		ret = PTR_ERR(host->clk);
1018 		goto out_irq;
1019 	}
1020 
1021 	ret = clk_prepare_enable(host->clk);
1022 	if (ret) {
1023 		dev_err(&pdev->dev, "cannot enable clock\n");
1024 		goto out_clk;
1025 	}
1026 
1027 	host->status = HOST_S_IDLE;
1028 
1029 	/* board-specific carddetect setup, if any */
1030 	if (host->platdata && host->platdata->cd_setup) {
1031 		ret = host->platdata->cd_setup(mmc, 1);
1032 		if (ret) {
1033 			dev_warn(&pdev->dev, "board CD setup failed\n");
1034 			mmc->caps |= MMC_CAP_NEEDS_POLL;
1035 		}
1036 	} else
1037 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1038 
1039 	/* platform may not be able to use all advertised caps */
1040 	if (host->platdata)
1041 		mmc->caps &= ~(host->platdata->mask_host_caps);
1042 
1043 	INIT_WORK(&host->data_bh_work, au1xmmc_data_bh_work);
1044 
1045 	INIT_WORK(&host->finish_bh_work, au1xmmc_finish_bh_work);
1046 
1047 	if (has_dbdma()) {
1048 		ret = au1xmmc_dbdma_init(host);
1049 		if (ret)
1050 			pr_info(DRIVER_NAME ": DBDMA init failed; using PIO\n");
1051 	}
1052 
1053 #ifdef CONFIG_LEDS_CLASS
1054 	if (host->platdata && host->platdata->led) {
1055 		struct led_classdev *led = host->platdata->led;
1056 		led->name = mmc_hostname(mmc);
1057 		led->brightness = LED_OFF;
1058 		led->default_trigger = mmc_hostname(mmc);
1059 		ret = led_classdev_register(mmc_dev(mmc), led);
1060 		if (ret)
1061 			goto out5;
1062 	}
1063 #endif
1064 
1065 	au1xmmc_reset_controller(host);
1066 
1067 	ret = mmc_add_host(mmc);
1068 	if (ret) {
1069 		dev_err(&pdev->dev, "cannot add mmc host\n");
1070 		goto out6;
1071 	}
1072 
1073 	platform_set_drvdata(pdev, host);
1074 
1075 	pr_info(DRIVER_NAME ": MMC Controller %d set up at %p"
1076 		" (mode=%s)\n", pdev->id, host->iobase,
1077 		host->flags & HOST_F_DMA ? "dma" : "pio");
1078 
1079 	return 0;	/* all ok */
1080 
1081 out6:
1082 #ifdef CONFIG_LEDS_CLASS
1083 	if (host->platdata && host->platdata->led)
1084 		led_classdev_unregister(host->platdata->led);
1085 out5:
1086 #endif
1087 	__raw_writel(0, HOST_ENABLE(host));
1088 	__raw_writel(0, HOST_CONFIG(host));
1089 	__raw_writel(0, HOST_CONFIG2(host));
1090 	wmb(); /* drain writebuffer */
1091 
1092 	if (host->flags & HOST_F_DBDMA)
1093 		au1xmmc_dbdma_shutdown(host);
1094 
1095 	cancel_work_sync(&host->data_bh_work);
1096 	cancel_work_sync(&host->finish_bh_work);
1097 
1098 	if (host->platdata && host->platdata->cd_setup &&
1099 	    !(mmc->caps & MMC_CAP_NEEDS_POLL))
1100 		host->platdata->cd_setup(mmc, 0);
1101 
1102 	clk_disable_unprepare(host->clk);
1103 out_clk:
1104 	clk_put(host->clk);
1105 out_irq:
1106 	free_irq(host->irq, host);
1107 out3:
1108 	iounmap((void *)host->iobase);
1109 out2:
1110 	release_resource(host->ioarea);
1111 	kfree(host->ioarea);
1112 out1:
1113 	mmc_free_host(mmc);
1114 out0:
1115 	return ret;
1116 }
1117 
1118 static void au1xmmc_remove(struct platform_device *pdev)
1119 {
1120 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1121 
1122 	if (host) {
1123 		mmc_remove_host(host->mmc);
1124 
1125 #ifdef CONFIG_LEDS_CLASS
1126 		if (host->platdata && host->platdata->led)
1127 			led_classdev_unregister(host->platdata->led);
1128 #endif
1129 
1130 		if (host->platdata && host->platdata->cd_setup &&
1131 		    !(host->mmc->caps & MMC_CAP_NEEDS_POLL))
1132 			host->platdata->cd_setup(host->mmc, 0);
1133 
1134 		__raw_writel(0, HOST_ENABLE(host));
1135 		__raw_writel(0, HOST_CONFIG(host));
1136 		__raw_writel(0, HOST_CONFIG2(host));
1137 		wmb(); /* drain writebuffer */
1138 
1139 		cancel_work_sync(&host->data_bh_work);
1140 		cancel_work_sync(&host->finish_bh_work);
1141 
1142 		if (host->flags & HOST_F_DBDMA)
1143 			au1xmmc_dbdma_shutdown(host);
1144 
1145 		au1xmmc_set_power(host, 0);
1146 
1147 		clk_disable_unprepare(host->clk);
1148 		clk_put(host->clk);
1149 
1150 		free_irq(host->irq, host);
1151 		iounmap((void *)host->iobase);
1152 		release_resource(host->ioarea);
1153 		kfree(host->ioarea);
1154 
1155 		mmc_free_host(host->mmc);
1156 	}
1157 }
1158 
1159 #ifdef CONFIG_PM
1160 static int au1xmmc_suspend(struct platform_device *pdev, pm_message_t state)
1161 {
1162 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1163 
1164 	__raw_writel(0, HOST_CONFIG2(host));
1165 	__raw_writel(0, HOST_CONFIG(host));
1166 	__raw_writel(0xffffffff, HOST_STATUS(host));
1167 	__raw_writel(0, HOST_ENABLE(host));
1168 	wmb(); /* drain writebuffer */
1169 
1170 	return 0;
1171 }
1172 
1173 static int au1xmmc_resume(struct platform_device *pdev)
1174 {
1175 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1176 
1177 	au1xmmc_reset_controller(host);
1178 
1179 	return 0;
1180 }
1181 #else
1182 #define au1xmmc_suspend NULL
1183 #define au1xmmc_resume NULL
1184 #endif
1185 
1186 static struct platform_driver au1xmmc_driver = {
1187 	.probe         = au1xmmc_probe,
1188 	.remove_new    = au1xmmc_remove,
1189 	.suspend       = au1xmmc_suspend,
1190 	.resume        = au1xmmc_resume,
1191 	.driver        = {
1192 		.name  = DRIVER_NAME,
1193 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1194 	},
1195 };
1196 
1197 static int __init au1xmmc_init(void)
1198 {
1199 	if (has_dbdma()) {
1200 		/* DSCR_CMD0_ALWAYS has a stride of 32 bits, we need a stride
1201 		* of 8 bits.  And since devices are shared, we need to create
1202 		* our own to avoid freaking out other devices.
1203 		*/
1204 		memid = au1xxx_ddma_add_device(&au1xmmc_mem_dbdev);
1205 		if (!memid)
1206 			pr_err("au1xmmc: cannot add memory dbdma\n");
1207 	}
1208 	return platform_driver_register(&au1xmmc_driver);
1209 }
1210 
1211 static void __exit au1xmmc_exit(void)
1212 {
1213 	if (has_dbdma() && memid)
1214 		au1xxx_ddma_del_device(memid);
1215 
1216 	platform_driver_unregister(&au1xmmc_driver);
1217 }
1218 
1219 module_init(au1xmmc_init);
1220 module_exit(au1xmmc_exit);
1221 
1222 MODULE_AUTHOR("Advanced Micro Devices, Inc");
1223 MODULE_DESCRIPTION("MMC/SD driver for the Alchemy Au1XXX");
1224 MODULE_LICENSE("GPL");
1225 MODULE_ALIAS("platform:au1xxx-mmc");
1226