xref: /openbmc/linux/drivers/mmc/host/au1xmmc.c (revision 20e2fc42)
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 
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 	void __iomem *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 	struct clk *clk;
122 };
123 
124 /* Status flags used by the host structure */
125 #define HOST_F_XMIT	0x0001
126 #define HOST_F_RECV	0x0002
127 #define HOST_F_DMA	0x0010
128 #define HOST_F_DBDMA	0x0020
129 #define HOST_F_ACTIVE	0x0100
130 #define HOST_F_STOP	0x1000
131 
132 #define HOST_S_IDLE	0x0001
133 #define HOST_S_CMD	0x0002
134 #define HOST_S_DATA	0x0003
135 #define HOST_S_STOP	0x0004
136 
137 /* Easy access macros */
138 #define HOST_STATUS(h)	((h)->iobase + SD_STATUS)
139 #define HOST_CONFIG(h)	((h)->iobase + SD_CONFIG)
140 #define HOST_ENABLE(h)	((h)->iobase + SD_ENABLE)
141 #define HOST_TXPORT(h)	((h)->iobase + SD_TXPORT)
142 #define HOST_RXPORT(h)	((h)->iobase + SD_RXPORT)
143 #define HOST_CMDARG(h)	((h)->iobase + SD_CMDARG)
144 #define HOST_BLKSIZE(h)	((h)->iobase + SD_BLKSIZE)
145 #define HOST_CMD(h)	((h)->iobase + SD_CMD)
146 #define HOST_CONFIG2(h)	((h)->iobase + SD_CONFIG2)
147 #define HOST_TIMEOUT(h)	((h)->iobase + SD_TIMEOUT)
148 #define HOST_DEBUG(h)	((h)->iobase + SD_DEBUG)
149 
150 #define DMA_CHANNEL(h)	\
151 	(((h)->flags & HOST_F_XMIT) ? (h)->tx_chan : (h)->rx_chan)
152 
153 static inline int has_dbdma(void)
154 {
155 	switch (alchemy_get_cputype()) {
156 	case ALCHEMY_CPU_AU1200:
157 	case ALCHEMY_CPU_AU1300:
158 		return 1;
159 	default:
160 		return 0;
161 	}
162 }
163 
164 static inline void IRQ_ON(struct au1xmmc_host *host, u32 mask)
165 {
166 	u32 val = __raw_readl(HOST_CONFIG(host));
167 	val |= mask;
168 	__raw_writel(val, HOST_CONFIG(host));
169 	wmb(); /* drain writebuffer */
170 }
171 
172 static inline void FLUSH_FIFO(struct au1xmmc_host *host)
173 {
174 	u32 val = __raw_readl(HOST_CONFIG2(host));
175 
176 	__raw_writel(val | SD_CONFIG2_FF, HOST_CONFIG2(host));
177 	wmb(); /* drain writebuffer */
178 	mdelay(1);
179 
180 	/* SEND_STOP will turn off clock control - this re-enables it */
181 	val &= ~SD_CONFIG2_DF;
182 
183 	__raw_writel(val, HOST_CONFIG2(host));
184 	wmb(); /* drain writebuffer */
185 }
186 
187 static inline void IRQ_OFF(struct au1xmmc_host *host, u32 mask)
188 {
189 	u32 val = __raw_readl(HOST_CONFIG(host));
190 	val &= ~mask;
191 	__raw_writel(val, HOST_CONFIG(host));
192 	wmb(); /* drain writebuffer */
193 }
194 
195 static inline void SEND_STOP(struct au1xmmc_host *host)
196 {
197 	u32 config2;
198 
199 	WARN_ON(host->status != HOST_S_DATA);
200 	host->status = HOST_S_STOP;
201 
202 	config2 = __raw_readl(HOST_CONFIG2(host));
203 	__raw_writel(config2 | SD_CONFIG2_DF, HOST_CONFIG2(host));
204 	wmb(); /* drain writebuffer */
205 
206 	/* Send the stop command */
207 	__raw_writel(STOP_CMD, HOST_CMD(host));
208 	wmb(); /* drain writebuffer */
209 }
210 
211 static void au1xmmc_set_power(struct au1xmmc_host *host, int state)
212 {
213 	if (host->platdata && host->platdata->set_power)
214 		host->platdata->set_power(host->mmc, state);
215 }
216 
217 static int au1xmmc_card_inserted(struct mmc_host *mmc)
218 {
219 	struct au1xmmc_host *host = mmc_priv(mmc);
220 
221 	if (host->platdata && host->platdata->card_inserted)
222 		return !!host->platdata->card_inserted(host->mmc);
223 
224 	return -ENOSYS;
225 }
226 
227 static int au1xmmc_card_readonly(struct mmc_host *mmc)
228 {
229 	struct au1xmmc_host *host = mmc_priv(mmc);
230 
231 	if (host->platdata && host->platdata->card_readonly)
232 		return !!host->platdata->card_readonly(mmc);
233 
234 	return -ENOSYS;
235 }
236 
237 static void au1xmmc_finish_request(struct au1xmmc_host *host)
238 {
239 	struct mmc_request *mrq = host->mrq;
240 
241 	host->mrq = NULL;
242 	host->flags &= HOST_F_ACTIVE | HOST_F_DMA;
243 
244 	host->dma.len = 0;
245 	host->dma.dir = 0;
246 
247 	host->pio.index  = 0;
248 	host->pio.offset = 0;
249 	host->pio.len = 0;
250 
251 	host->status = HOST_S_IDLE;
252 
253 	mmc_request_done(host->mmc, mrq);
254 }
255 
256 static void au1xmmc_tasklet_finish(unsigned long param)
257 {
258 	struct au1xmmc_host *host = (struct au1xmmc_host *) param;
259 	au1xmmc_finish_request(host);
260 }
261 
262 static int au1xmmc_send_command(struct au1xmmc_host *host, int wait,
263 				struct mmc_command *cmd, struct mmc_data *data)
264 {
265 	u32 mmccmd = (cmd->opcode << SD_CMD_CI_SHIFT);
266 
267 	switch (mmc_resp_type(cmd)) {
268 	case MMC_RSP_NONE:
269 		break;
270 	case MMC_RSP_R1:
271 		mmccmd |= SD_CMD_RT_1;
272 		break;
273 	case MMC_RSP_R1B:
274 		mmccmd |= SD_CMD_RT_1B;
275 		break;
276 	case MMC_RSP_R2:
277 		mmccmd |= SD_CMD_RT_2;
278 		break;
279 	case MMC_RSP_R3:
280 		mmccmd |= SD_CMD_RT_3;
281 		break;
282 	default:
283 		pr_info("au1xmmc: unhandled response type %02x\n",
284 			mmc_resp_type(cmd));
285 		return -EINVAL;
286 	}
287 
288 	if (data) {
289 		if (data->flags & MMC_DATA_READ) {
290 			if (data->blocks > 1)
291 				mmccmd |= SD_CMD_CT_4;
292 			else
293 				mmccmd |= SD_CMD_CT_2;
294 		} else if (data->flags & MMC_DATA_WRITE) {
295 			if (data->blocks > 1)
296 				mmccmd |= SD_CMD_CT_3;
297 			else
298 				mmccmd |= SD_CMD_CT_1;
299 		}
300 	}
301 
302 	__raw_writel(cmd->arg, HOST_CMDARG(host));
303 	wmb(); /* drain writebuffer */
304 
305 	if (wait)
306 		IRQ_OFF(host, SD_CONFIG_CR);
307 
308 	__raw_writel((mmccmd | SD_CMD_GO), HOST_CMD(host));
309 	wmb(); /* drain writebuffer */
310 
311 	/* Wait for the command to go on the line */
312 	while (__raw_readl(HOST_CMD(host)) & SD_CMD_GO)
313 		/* nop */;
314 
315 	/* Wait for the command to come back */
316 	if (wait) {
317 		u32 status = __raw_readl(HOST_STATUS(host));
318 
319 		while (!(status & SD_STATUS_CR))
320 			status = __raw_readl(HOST_STATUS(host));
321 
322 		/* Clear the CR status */
323 		__raw_writel(SD_STATUS_CR, HOST_STATUS(host));
324 
325 		IRQ_ON(host, SD_CONFIG_CR);
326 	}
327 
328 	return 0;
329 }
330 
331 static void au1xmmc_data_complete(struct au1xmmc_host *host, u32 status)
332 {
333 	struct mmc_request *mrq = host->mrq;
334 	struct mmc_data *data;
335 	u32 crc;
336 
337 	WARN_ON((host->status != HOST_S_DATA) && (host->status != HOST_S_STOP));
338 
339 	if (host->mrq == NULL)
340 		return;
341 
342 	data = mrq->cmd->data;
343 
344 	if (status == 0)
345 		status = __raw_readl(HOST_STATUS(host));
346 
347 	/* The transaction is really over when the SD_STATUS_DB bit is clear */
348 	while ((host->flags & HOST_F_XMIT) && (status & SD_STATUS_DB))
349 		status = __raw_readl(HOST_STATUS(host));
350 
351 	data->error = 0;
352 	dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len, host->dma.dir);
353 
354         /* Process any errors */
355 	crc = (status & (SD_STATUS_WC | SD_STATUS_RC));
356 	if (host->flags & HOST_F_XMIT)
357 		crc |= ((status & 0x07) == 0x02) ? 0 : 1;
358 
359 	if (crc)
360 		data->error = -EILSEQ;
361 
362 	/* Clear the CRC bits */
363 	__raw_writel(SD_STATUS_WC | SD_STATUS_RC, HOST_STATUS(host));
364 
365 	data->bytes_xfered = 0;
366 
367 	if (!data->error) {
368 		if (host->flags & (HOST_F_DMA | HOST_F_DBDMA)) {
369 			u32 chan = DMA_CHANNEL(host);
370 
371 			chan_tab_t *c = *((chan_tab_t **)chan);
372 			au1x_dma_chan_t *cp = c->chan_ptr;
373 			data->bytes_xfered = cp->ddma_bytecnt;
374 		} else
375 			data->bytes_xfered =
376 				(data->blocks * data->blksz) - host->pio.len;
377 	}
378 
379 	au1xmmc_finish_request(host);
380 }
381 
382 static void au1xmmc_tasklet_data(unsigned long param)
383 {
384 	struct au1xmmc_host *host = (struct au1xmmc_host *)param;
385 
386 	u32 status = __raw_readl(HOST_STATUS(host));
387 	au1xmmc_data_complete(host, status);
388 }
389 
390 #define AU1XMMC_MAX_TRANSFER 8
391 
392 static void au1xmmc_send_pio(struct au1xmmc_host *host)
393 {
394 	struct mmc_data *data;
395 	int sg_len, max, count;
396 	unsigned char *sg_ptr, val;
397 	u32 status;
398 	struct scatterlist *sg;
399 
400 	data = host->mrq->data;
401 
402 	if (!(host->flags & HOST_F_XMIT))
403 		return;
404 
405 	/* This is the pointer to the data buffer */
406 	sg = &data->sg[host->pio.index];
407 	sg_ptr = kmap_atomic(sg_page(sg)) + sg->offset + host->pio.offset;
408 
409 	/* This is the space left inside the buffer */
410 	sg_len = data->sg[host->pio.index].length - host->pio.offset;
411 
412 	/* Check if we need less than the size of the sg_buffer */
413 	max = (sg_len > host->pio.len) ? host->pio.len : sg_len;
414 	if (max > AU1XMMC_MAX_TRANSFER)
415 		max = AU1XMMC_MAX_TRANSFER;
416 
417 	for (count = 0; count < max; count++) {
418 		status = __raw_readl(HOST_STATUS(host));
419 
420 		if (!(status & SD_STATUS_TH))
421 			break;
422 
423 		val = sg_ptr[count];
424 
425 		__raw_writel((unsigned long)val, HOST_TXPORT(host));
426 		wmb(); /* drain writebuffer */
427 	}
428 	kunmap_atomic(sg_ptr);
429 
430 	host->pio.len -= count;
431 	host->pio.offset += count;
432 
433 	if (count == sg_len) {
434 		host->pio.index++;
435 		host->pio.offset = 0;
436 	}
437 
438 	if (host->pio.len == 0) {
439 		IRQ_OFF(host, SD_CONFIG_TH);
440 
441 		if (host->flags & HOST_F_STOP)
442 			SEND_STOP(host);
443 
444 		tasklet_schedule(&host->data_task);
445 	}
446 }
447 
448 static void au1xmmc_receive_pio(struct au1xmmc_host *host)
449 {
450 	struct mmc_data *data;
451 	int max, count, sg_len = 0;
452 	unsigned char *sg_ptr = NULL;
453 	u32 status, val;
454 	struct scatterlist *sg;
455 
456 	data = host->mrq->data;
457 
458 	if (!(host->flags & HOST_F_RECV))
459 		return;
460 
461 	max = host->pio.len;
462 
463 	if (host->pio.index < host->dma.len) {
464 		sg = &data->sg[host->pio.index];
465 		sg_ptr = kmap_atomic(sg_page(sg)) + sg->offset + host->pio.offset;
466 
467 		/* This is the space left inside the buffer */
468 		sg_len = sg_dma_len(&data->sg[host->pio.index]) - host->pio.offset;
469 
470 		/* Check if we need less than the size of the sg_buffer */
471 		if (sg_len < max)
472 			max = sg_len;
473 	}
474 
475 	if (max > AU1XMMC_MAX_TRANSFER)
476 		max = AU1XMMC_MAX_TRANSFER;
477 
478 	for (count = 0; count < max; count++) {
479 		status = __raw_readl(HOST_STATUS(host));
480 
481 		if (!(status & SD_STATUS_NE))
482 			break;
483 
484 		if (status & SD_STATUS_RC) {
485 			DBG("RX CRC Error [%d + %d].\n", host->pdev->id,
486 					host->pio.len, count);
487 			break;
488 		}
489 
490 		if (status & SD_STATUS_RO) {
491 			DBG("RX Overrun [%d + %d]\n", host->pdev->id,
492 					host->pio.len, count);
493 			break;
494 		}
495 		else if (status & SD_STATUS_RU) {
496 			DBG("RX Underrun [%d + %d]\n", host->pdev->id,
497 					host->pio.len,	count);
498 			break;
499 		}
500 
501 		val = __raw_readl(HOST_RXPORT(host));
502 
503 		if (sg_ptr)
504 			sg_ptr[count] = (unsigned char)(val & 0xFF);
505 	}
506 	if (sg_ptr)
507 		kunmap_atomic(sg_ptr);
508 
509 	host->pio.len -= count;
510 	host->pio.offset += count;
511 
512 	if (sg_len && count == sg_len) {
513 		host->pio.index++;
514 		host->pio.offset = 0;
515 	}
516 
517 	if (host->pio.len == 0) {
518 		/* IRQ_OFF(host, SD_CONFIG_RA | SD_CONFIG_RF); */
519 		IRQ_OFF(host, SD_CONFIG_NE);
520 
521 		if (host->flags & HOST_F_STOP)
522 			SEND_STOP(host);
523 
524 		tasklet_schedule(&host->data_task);
525 	}
526 }
527 
528 /* This is called when a command has been completed - grab the response
529  * and check for errors.  Then start the data transfer if it is indicated.
530  */
531 static void au1xmmc_cmd_complete(struct au1xmmc_host *host, u32 status)
532 {
533 	struct mmc_request *mrq = host->mrq;
534 	struct mmc_command *cmd;
535 	u32 r[4];
536 	int i, trans;
537 
538 	if (!host->mrq)
539 		return;
540 
541 	cmd = mrq->cmd;
542 	cmd->error = 0;
543 
544 	if (cmd->flags & MMC_RSP_PRESENT) {
545 		if (cmd->flags & MMC_RSP_136) {
546 			r[0] = __raw_readl(host->iobase + SD_RESP3);
547 			r[1] = __raw_readl(host->iobase + SD_RESP2);
548 			r[2] = __raw_readl(host->iobase + SD_RESP1);
549 			r[3] = __raw_readl(host->iobase + SD_RESP0);
550 
551 			/* The CRC is omitted from the response, so really
552 			 * we only got 120 bytes, but the engine expects
553 			 * 128 bits, so we have to shift things up.
554 			 */
555 			for (i = 0; i < 4; i++) {
556 				cmd->resp[i] = (r[i] & 0x00FFFFFF) << 8;
557 				if (i != 3)
558 					cmd->resp[i] |= (r[i + 1] & 0xFF000000) >> 24;
559 			}
560 		} else {
561 			/* Techincally, we should be getting all 48 bits of
562 			 * the response (SD_RESP1 + SD_RESP2), but because
563 			 * our response omits the CRC, our data ends up
564 			 * being shifted 8 bits to the right.  In this case,
565 			 * that means that the OSR data starts at bit 31,
566 			 * so we can just read RESP0 and return that.
567 			 */
568 			cmd->resp[0] = __raw_readl(host->iobase + SD_RESP0);
569 		}
570 	}
571 
572         /* Figure out errors */
573 	if (status & (SD_STATUS_SC | SD_STATUS_WC | SD_STATUS_RC))
574 		cmd->error = -EILSEQ;
575 
576 	trans = host->flags & (HOST_F_XMIT | HOST_F_RECV);
577 
578 	if (!trans || cmd->error) {
579 		IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF);
580 		tasklet_schedule(&host->finish_task);
581 		return;
582 	}
583 
584 	host->status = HOST_S_DATA;
585 
586 	if ((host->flags & (HOST_F_DMA | HOST_F_DBDMA))) {
587 		u32 channel = DMA_CHANNEL(host);
588 
589 		/* Start the DBDMA as soon as the buffer gets something in it */
590 
591 		if (host->flags & HOST_F_RECV) {
592 			u32 mask = SD_STATUS_DB | SD_STATUS_NE;
593 
594 			while((status & mask) != mask)
595 				status = __raw_readl(HOST_STATUS(host));
596 		}
597 
598 		au1xxx_dbdma_start(channel);
599 	}
600 }
601 
602 static void au1xmmc_set_clock(struct au1xmmc_host *host, int rate)
603 {
604 	unsigned int pbus = clk_get_rate(host->clk);
605 	unsigned int divisor = ((pbus / rate) / 2) - 1;
606 	u32 config;
607 
608 	config = __raw_readl(HOST_CONFIG(host));
609 
610 	config &= ~(SD_CONFIG_DIV);
611 	config |= (divisor & SD_CONFIG_DIV) | SD_CONFIG_DE;
612 
613 	__raw_writel(config, HOST_CONFIG(host));
614 	wmb(); /* drain writebuffer */
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 	__raw_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 	__raw_writel(SD_ENABLE_CE, HOST_ENABLE(host));
726 	wmb(); /* drain writebuffer */
727 	mdelay(1);
728 
729 	__raw_writel(SD_ENABLE_R | SD_ENABLE_CE, HOST_ENABLE(host));
730 	wmb(); /* drain writebuffer */
731 	mdelay(5);
732 
733 	__raw_writel(~0, HOST_STATUS(host));
734 	wmb(); /* drain writebuffer */
735 
736 	__raw_writel(0, HOST_BLKSIZE(host));
737 	__raw_writel(0x001fffff, HOST_TIMEOUT(host));
738 	wmb(); /* drain writebuffer */
739 
740 	__raw_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
741 	wmb(); /* drain writebuffer */
742 
743 	__raw_writel(SD_CONFIG2_EN | SD_CONFIG2_FF, HOST_CONFIG2(host));
744 	wmb(); /* drain writebuffer */
745 	mdelay(1);
746 
747 	__raw_writel(SD_CONFIG2_EN, HOST_CONFIG2(host));
748 	wmb(); /* drain writebuffer */
749 
750 	/* Configure interrupts */
751 	__raw_writel(AU1XMMC_INTERRUPTS, HOST_CONFIG(host));
752 	wmb(); /* drain writebuffer */
753 }
754 
755 
756 static void au1xmmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
757 {
758 	struct au1xmmc_host *host = mmc_priv(mmc);
759 	u32 config2;
760 
761 	if (ios->power_mode == MMC_POWER_OFF)
762 		au1xmmc_set_power(host, 0);
763 	else if (ios->power_mode == MMC_POWER_ON) {
764 		au1xmmc_set_power(host, 1);
765 	}
766 
767 	if (ios->clock && ios->clock != host->clock) {
768 		au1xmmc_set_clock(host, ios->clock);
769 		host->clock = ios->clock;
770 	}
771 
772 	config2 = __raw_readl(HOST_CONFIG2(host));
773 	switch (ios->bus_width) {
774 	case MMC_BUS_WIDTH_8:
775 		config2 |= SD_CONFIG2_BB;
776 		break;
777 	case MMC_BUS_WIDTH_4:
778 		config2 &= ~SD_CONFIG2_BB;
779 		config2 |= SD_CONFIG2_WB;
780 		break;
781 	case MMC_BUS_WIDTH_1:
782 		config2 &= ~(SD_CONFIG2_WB | SD_CONFIG2_BB);
783 		break;
784 	}
785 	__raw_writel(config2, HOST_CONFIG2(host));
786 	wmb(); /* drain writebuffer */
787 }
788 
789 #define STATUS_TIMEOUT (SD_STATUS_RAT | SD_STATUS_DT)
790 #define STATUS_DATA_IN  (SD_STATUS_NE)
791 #define STATUS_DATA_OUT (SD_STATUS_TH)
792 
793 static irqreturn_t au1xmmc_irq(int irq, void *dev_id)
794 {
795 	struct au1xmmc_host *host = dev_id;
796 	u32 status;
797 
798 	status = __raw_readl(HOST_STATUS(host));
799 
800 	if (!(status & SD_STATUS_I))
801 		return IRQ_NONE;	/* not ours */
802 
803 	if (status & SD_STATUS_SI)	/* SDIO */
804 		mmc_signal_sdio_irq(host->mmc);
805 
806 	if (host->mrq && (status & STATUS_TIMEOUT)) {
807 		if (status & SD_STATUS_RAT)
808 			host->mrq->cmd->error = -ETIMEDOUT;
809 		else if (status & SD_STATUS_DT)
810 			host->mrq->data->error = -ETIMEDOUT;
811 
812 		/* In PIO mode, interrupts might still be enabled */
813 		IRQ_OFF(host, SD_CONFIG_NE | SD_CONFIG_TH);
814 
815 		/* IRQ_OFF(host, SD_CONFIG_TH | SD_CONFIG_RA | SD_CONFIG_RF); */
816 		tasklet_schedule(&host->finish_task);
817 	}
818 #if 0
819 	else if (status & SD_STATUS_DD) {
820 		/* Sometimes we get a DD before a NE in PIO mode */
821 		if (!(host->flags & HOST_F_DMA) && (status & SD_STATUS_NE))
822 			au1xmmc_receive_pio(host);
823 		else {
824 			au1xmmc_data_complete(host, status);
825 			/* tasklet_schedule(&host->data_task); */
826 		}
827 	}
828 #endif
829 	else if (status & SD_STATUS_CR) {
830 		if (host->status == HOST_S_CMD)
831 			au1xmmc_cmd_complete(host, status);
832 
833 	} else if (!(host->flags & HOST_F_DMA)) {
834 		if ((host->flags & HOST_F_XMIT) && (status & STATUS_DATA_OUT))
835 			au1xmmc_send_pio(host);
836 		else if ((host->flags & HOST_F_RECV) && (status & STATUS_DATA_IN))
837 			au1xmmc_receive_pio(host);
838 
839 	} else if (status & 0x203F3C70) {
840 			DBG("Unhandled status %8.8x\n", host->pdev->id,
841 				status);
842 	}
843 
844 	__raw_writel(status, HOST_STATUS(host));
845 	wmb(); /* drain writebuffer */
846 
847 	return IRQ_HANDLED;
848 }
849 
850 /* 8bit memory DMA device */
851 static dbdev_tab_t au1xmmc_mem_dbdev = {
852 	.dev_id		= DSCR_CMD0_ALWAYS,
853 	.dev_flags	= DEV_FLAGS_ANYUSE,
854 	.dev_tsize	= 0,
855 	.dev_devwidth	= 8,
856 	.dev_physaddr	= 0x00000000,
857 	.dev_intlevel	= 0,
858 	.dev_intpolarity = 0,
859 };
860 static int memid;
861 
862 static void au1xmmc_dbdma_callback(int irq, void *dev_id)
863 {
864 	struct au1xmmc_host *host = (struct au1xmmc_host *)dev_id;
865 
866 	/* Avoid spurious interrupts */
867 	if (!host->mrq)
868 		return;
869 
870 	if (host->flags & HOST_F_STOP)
871 		SEND_STOP(host);
872 
873 	tasklet_schedule(&host->data_task);
874 }
875 
876 static int au1xmmc_dbdma_init(struct au1xmmc_host *host)
877 {
878 	struct resource *res;
879 	int txid, rxid;
880 
881 	res = platform_get_resource(host->pdev, IORESOURCE_DMA, 0);
882 	if (!res)
883 		return -ENODEV;
884 	txid = res->start;
885 
886 	res = platform_get_resource(host->pdev, IORESOURCE_DMA, 1);
887 	if (!res)
888 		return -ENODEV;
889 	rxid = res->start;
890 
891 	if (!memid)
892 		return -ENODEV;
893 
894 	host->tx_chan = au1xxx_dbdma_chan_alloc(memid, txid,
895 				au1xmmc_dbdma_callback, (void *)host);
896 	if (!host->tx_chan) {
897 		dev_err(&host->pdev->dev, "cannot allocate TX DMA\n");
898 		return -ENODEV;
899 	}
900 
901 	host->rx_chan = au1xxx_dbdma_chan_alloc(rxid, memid,
902 				au1xmmc_dbdma_callback, (void *)host);
903 	if (!host->rx_chan) {
904 		dev_err(&host->pdev->dev, "cannot allocate RX DMA\n");
905 		au1xxx_dbdma_chan_free(host->tx_chan);
906 		return -ENODEV;
907 	}
908 
909 	au1xxx_dbdma_set_devwidth(host->tx_chan, 8);
910 	au1xxx_dbdma_set_devwidth(host->rx_chan, 8);
911 
912 	au1xxx_dbdma_ring_alloc(host->tx_chan, AU1XMMC_DESCRIPTOR_COUNT);
913 	au1xxx_dbdma_ring_alloc(host->rx_chan, AU1XMMC_DESCRIPTOR_COUNT);
914 
915 	/* DBDMA is good to go */
916 	host->flags |= HOST_F_DMA | HOST_F_DBDMA;
917 
918 	return 0;
919 }
920 
921 static void au1xmmc_dbdma_shutdown(struct au1xmmc_host *host)
922 {
923 	if (host->flags & HOST_F_DMA) {
924 		host->flags &= ~HOST_F_DMA;
925 		au1xxx_dbdma_chan_free(host->tx_chan);
926 		au1xxx_dbdma_chan_free(host->rx_chan);
927 	}
928 }
929 
930 static void au1xmmc_enable_sdio_irq(struct mmc_host *mmc, int en)
931 {
932 	struct au1xmmc_host *host = mmc_priv(mmc);
933 
934 	if (en)
935 		IRQ_ON(host, SD_CONFIG_SI);
936 	else
937 		IRQ_OFF(host, SD_CONFIG_SI);
938 }
939 
940 static const struct mmc_host_ops au1xmmc_ops = {
941 	.request	= au1xmmc_request,
942 	.set_ios	= au1xmmc_set_ios,
943 	.get_ro		= au1xmmc_card_readonly,
944 	.get_cd		= au1xmmc_card_inserted,
945 	.enable_sdio_irq = au1xmmc_enable_sdio_irq,
946 };
947 
948 static int au1xmmc_probe(struct platform_device *pdev)
949 {
950 	struct mmc_host *mmc;
951 	struct au1xmmc_host *host;
952 	struct resource *r;
953 	int ret, iflag;
954 
955 	mmc = mmc_alloc_host(sizeof(struct au1xmmc_host), &pdev->dev);
956 	if (!mmc) {
957 		dev_err(&pdev->dev, "no memory for mmc_host\n");
958 		ret = -ENOMEM;
959 		goto out0;
960 	}
961 
962 	host = mmc_priv(mmc);
963 	host->mmc = mmc;
964 	host->platdata = pdev->dev.platform_data;
965 	host->pdev = pdev;
966 
967 	ret = -ENODEV;
968 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
969 	if (!r) {
970 		dev_err(&pdev->dev, "no mmio defined\n");
971 		goto out1;
972 	}
973 
974 	host->ioarea = request_mem_region(r->start, resource_size(r),
975 					   pdev->name);
976 	if (!host->ioarea) {
977 		dev_err(&pdev->dev, "mmio already in use\n");
978 		goto out1;
979 	}
980 
981 	host->iobase = ioremap(r->start, 0x3c);
982 	if (!host->iobase) {
983 		dev_err(&pdev->dev, "cannot remap mmio\n");
984 		goto out2;
985 	}
986 
987 	r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
988 	if (!r) {
989 		dev_err(&pdev->dev, "no IRQ defined\n");
990 		goto out3;
991 	}
992 	host->irq = r->start;
993 
994 	mmc->ops = &au1xmmc_ops;
995 
996 	mmc->f_min =   450000;
997 	mmc->f_max = 24000000;
998 
999 	mmc->max_blk_size = 2048;
1000 	mmc->max_blk_count = 512;
1001 
1002 	mmc->ocr_avail = AU1XMMC_OCR;
1003 	mmc->caps = MMC_CAP_4_BIT_DATA | MMC_CAP_SDIO_IRQ;
1004 	mmc->max_segs = AU1XMMC_DESCRIPTOR_COUNT;
1005 
1006 	iflag = IRQF_SHARED;	/* Au1100/Au1200: one int for both ctrls */
1007 
1008 	switch (alchemy_get_cputype()) {
1009 	case ALCHEMY_CPU_AU1100:
1010 		mmc->max_seg_size = AU1100_MMC_DESCRIPTOR_SIZE;
1011 		break;
1012 	case ALCHEMY_CPU_AU1200:
1013 		mmc->max_seg_size = AU1200_MMC_DESCRIPTOR_SIZE;
1014 		break;
1015 	case ALCHEMY_CPU_AU1300:
1016 		iflag = 0;	/* nothing is shared */
1017 		mmc->max_seg_size = AU1200_MMC_DESCRIPTOR_SIZE;
1018 		mmc->f_max = 52000000;
1019 		if (host->ioarea->start == AU1100_SD0_PHYS_ADDR)
1020 			mmc->caps |= MMC_CAP_8_BIT_DATA;
1021 		break;
1022 	}
1023 
1024 	ret = request_irq(host->irq, au1xmmc_irq, iflag, DRIVER_NAME, host);
1025 	if (ret) {
1026 		dev_err(&pdev->dev, "cannot grab IRQ\n");
1027 		goto out3;
1028 	}
1029 
1030 	host->clk = clk_get(&pdev->dev, ALCHEMY_PERIPH_CLK);
1031 	if (IS_ERR(host->clk)) {
1032 		dev_err(&pdev->dev, "cannot find clock\n");
1033 		ret = PTR_ERR(host->clk);
1034 		goto out_irq;
1035 	}
1036 
1037 	ret = clk_prepare_enable(host->clk);
1038 	if (ret) {
1039 		dev_err(&pdev->dev, "cannot enable clock\n");
1040 		goto out_clk;
1041 	}
1042 
1043 	host->status = HOST_S_IDLE;
1044 
1045 	/* board-specific carddetect setup, if any */
1046 	if (host->platdata && host->platdata->cd_setup) {
1047 		ret = host->platdata->cd_setup(mmc, 1);
1048 		if (ret) {
1049 			dev_warn(&pdev->dev, "board CD setup failed\n");
1050 			mmc->caps |= MMC_CAP_NEEDS_POLL;
1051 		}
1052 	} else
1053 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1054 
1055 	/* platform may not be able to use all advertised caps */
1056 	if (host->platdata)
1057 		mmc->caps &= ~(host->platdata->mask_host_caps);
1058 
1059 	tasklet_init(&host->data_task, au1xmmc_tasklet_data,
1060 			(unsigned long)host);
1061 
1062 	tasklet_init(&host->finish_task, au1xmmc_tasklet_finish,
1063 			(unsigned long)host);
1064 
1065 	if (has_dbdma()) {
1066 		ret = au1xmmc_dbdma_init(host);
1067 		if (ret)
1068 			pr_info(DRIVER_NAME ": DBDMA init failed; using PIO\n");
1069 	}
1070 
1071 #ifdef CONFIG_LEDS_CLASS
1072 	if (host->platdata && host->platdata->led) {
1073 		struct led_classdev *led = host->platdata->led;
1074 		led->name = mmc_hostname(mmc);
1075 		led->brightness = LED_OFF;
1076 		led->default_trigger = mmc_hostname(mmc);
1077 		ret = led_classdev_register(mmc_dev(mmc), led);
1078 		if (ret)
1079 			goto out5;
1080 	}
1081 #endif
1082 
1083 	au1xmmc_reset_controller(host);
1084 
1085 	ret = mmc_add_host(mmc);
1086 	if (ret) {
1087 		dev_err(&pdev->dev, "cannot add mmc host\n");
1088 		goto out6;
1089 	}
1090 
1091 	platform_set_drvdata(pdev, host);
1092 
1093 	pr_info(DRIVER_NAME ": MMC Controller %d set up at %p"
1094 		" (mode=%s)\n", pdev->id, host->iobase,
1095 		host->flags & HOST_F_DMA ? "dma" : "pio");
1096 
1097 	return 0;	/* all ok */
1098 
1099 out6:
1100 #ifdef CONFIG_LEDS_CLASS
1101 	if (host->platdata && host->platdata->led)
1102 		led_classdev_unregister(host->platdata->led);
1103 out5:
1104 #endif
1105 	__raw_writel(0, HOST_ENABLE(host));
1106 	__raw_writel(0, HOST_CONFIG(host));
1107 	__raw_writel(0, HOST_CONFIG2(host));
1108 	wmb(); /* drain writebuffer */
1109 
1110 	if (host->flags & HOST_F_DBDMA)
1111 		au1xmmc_dbdma_shutdown(host);
1112 
1113 	tasklet_kill(&host->data_task);
1114 	tasklet_kill(&host->finish_task);
1115 
1116 	if (host->platdata && host->platdata->cd_setup &&
1117 	    !(mmc->caps & MMC_CAP_NEEDS_POLL))
1118 		host->platdata->cd_setup(mmc, 0);
1119 out_clk:
1120 	clk_disable_unprepare(host->clk);
1121 	clk_put(host->clk);
1122 out_irq:
1123 	free_irq(host->irq, host);
1124 out3:
1125 	iounmap((void *)host->iobase);
1126 out2:
1127 	release_resource(host->ioarea);
1128 	kfree(host->ioarea);
1129 out1:
1130 	mmc_free_host(mmc);
1131 out0:
1132 	return ret;
1133 }
1134 
1135 static int au1xmmc_remove(struct platform_device *pdev)
1136 {
1137 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1138 
1139 	if (host) {
1140 		mmc_remove_host(host->mmc);
1141 
1142 #ifdef CONFIG_LEDS_CLASS
1143 		if (host->platdata && host->platdata->led)
1144 			led_classdev_unregister(host->platdata->led);
1145 #endif
1146 
1147 		if (host->platdata && host->platdata->cd_setup &&
1148 		    !(host->mmc->caps & MMC_CAP_NEEDS_POLL))
1149 			host->platdata->cd_setup(host->mmc, 0);
1150 
1151 		__raw_writel(0, HOST_ENABLE(host));
1152 		__raw_writel(0, HOST_CONFIG(host));
1153 		__raw_writel(0, HOST_CONFIG2(host));
1154 		wmb(); /* drain writebuffer */
1155 
1156 		tasklet_kill(&host->data_task);
1157 		tasklet_kill(&host->finish_task);
1158 
1159 		if (host->flags & HOST_F_DBDMA)
1160 			au1xmmc_dbdma_shutdown(host);
1161 
1162 		au1xmmc_set_power(host, 0);
1163 
1164 		clk_disable_unprepare(host->clk);
1165 		clk_put(host->clk);
1166 
1167 		free_irq(host->irq, host);
1168 		iounmap((void *)host->iobase);
1169 		release_resource(host->ioarea);
1170 		kfree(host->ioarea);
1171 
1172 		mmc_free_host(host->mmc);
1173 	}
1174 	return 0;
1175 }
1176 
1177 #ifdef CONFIG_PM
1178 static int au1xmmc_suspend(struct platform_device *pdev, pm_message_t state)
1179 {
1180 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1181 
1182 	__raw_writel(0, HOST_CONFIG2(host));
1183 	__raw_writel(0, HOST_CONFIG(host));
1184 	__raw_writel(0xffffffff, HOST_STATUS(host));
1185 	__raw_writel(0, HOST_ENABLE(host));
1186 	wmb(); /* drain writebuffer */
1187 
1188 	return 0;
1189 }
1190 
1191 static int au1xmmc_resume(struct platform_device *pdev)
1192 {
1193 	struct au1xmmc_host *host = platform_get_drvdata(pdev);
1194 
1195 	au1xmmc_reset_controller(host);
1196 
1197 	return 0;
1198 }
1199 #else
1200 #define au1xmmc_suspend NULL
1201 #define au1xmmc_resume NULL
1202 #endif
1203 
1204 static struct platform_driver au1xmmc_driver = {
1205 	.probe         = au1xmmc_probe,
1206 	.remove        = au1xmmc_remove,
1207 	.suspend       = au1xmmc_suspend,
1208 	.resume        = au1xmmc_resume,
1209 	.driver        = {
1210 		.name  = DRIVER_NAME,
1211 	},
1212 };
1213 
1214 static int __init au1xmmc_init(void)
1215 {
1216 	if (has_dbdma()) {
1217 		/* DSCR_CMD0_ALWAYS has a stride of 32 bits, we need a stride
1218 		* of 8 bits.  And since devices are shared, we need to create
1219 		* our own to avoid freaking out other devices.
1220 		*/
1221 		memid = au1xxx_ddma_add_device(&au1xmmc_mem_dbdev);
1222 		if (!memid)
1223 			pr_err("au1xmmc: cannot add memory dbdma\n");
1224 	}
1225 	return platform_driver_register(&au1xmmc_driver);
1226 }
1227 
1228 static void __exit au1xmmc_exit(void)
1229 {
1230 	if (has_dbdma() && memid)
1231 		au1xxx_ddma_del_device(memid);
1232 
1233 	platform_driver_unregister(&au1xmmc_driver);
1234 }
1235 
1236 module_init(au1xmmc_init);
1237 module_exit(au1xmmc_exit);
1238 
1239 MODULE_AUTHOR("Advanced Micro Devices, Inc");
1240 MODULE_DESCRIPTION("MMC/SD driver for the Alchemy Au1XXX");
1241 MODULE_LICENSE("GPL");
1242 MODULE_ALIAS("platform:au1xxx-mmc");
1243