xref: /openbmc/linux/drivers/mmc/host/mmci.c (revision ab73b751)
1 /*
2  *  linux/drivers/mmc/host/mmci.c - ARM PrimeCell MMCI PL180/1 driver
3  *
4  *  Copyright (C) 2003 Deep Blue Solutions, Ltd, All Rights Reserved.
5  *  Copyright (C) 2010 ST-Ericsson SA
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/module.h>
12 #include <linux/moduleparam.h>
13 #include <linux/init.h>
14 #include <linux/ioport.h>
15 #include <linux/device.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
20 #include <linux/err.h>
21 #include <linux/highmem.h>
22 #include <linux/log2.h>
23 #include <linux/mmc/host.h>
24 #include <linux/mmc/card.h>
25 #include <linux/amba/bus.h>
26 #include <linux/clk.h>
27 #include <linux/scatterlist.h>
28 #include <linux/gpio.h>
29 #include <linux/of_gpio.h>
30 #include <linux/regulator/consumer.h>
31 #include <linux/dmaengine.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/amba/mmci.h>
34 #include <linux/pm_runtime.h>
35 #include <linux/types.h>
36 
37 #include <asm/div64.h>
38 #include <asm/io.h>
39 #include <asm/sizes.h>
40 
41 #include "mmci.h"
42 
43 #define DRIVER_NAME "mmci-pl18x"
44 
45 static unsigned int fmax = 515633;
46 
47 /**
48  * struct variant_data - MMCI variant-specific quirks
49  * @clkreg: default value for MCICLOCK register
50  * @clkreg_enable: enable value for MMCICLOCK register
51  * @datalength_bits: number of bits in the MMCIDATALENGTH register
52  * @fifosize: number of bytes that can be written when MMCI_TXFIFOEMPTY
53  *	      is asserted (likewise for RX)
54  * @fifohalfsize: number of bytes that can be written when MCI_TXFIFOHALFEMPTY
55  *		  is asserted (likewise for RX)
56  * @sdio: variant supports SDIO
57  * @st_clkdiv: true if using a ST-specific clock divider algorithm
58  * @blksz_datactrl16: true if Block size is at b16..b30 position in datactrl register
59  * @pwrreg_powerup: power up value for MMCIPOWER register
60  * @signal_direction: input/out direction of bus signals can be indicated
61  */
62 struct variant_data {
63 	unsigned int		clkreg;
64 	unsigned int		clkreg_enable;
65 	unsigned int		datalength_bits;
66 	unsigned int		fifosize;
67 	unsigned int		fifohalfsize;
68 	bool			sdio;
69 	bool			st_clkdiv;
70 	bool			blksz_datactrl16;
71 	u32			pwrreg_powerup;
72 	bool			signal_direction;
73 };
74 
75 static struct variant_data variant_arm = {
76 	.fifosize		= 16 * 4,
77 	.fifohalfsize		= 8 * 4,
78 	.datalength_bits	= 16,
79 	.pwrreg_powerup		= MCI_PWR_UP,
80 };
81 
82 static struct variant_data variant_arm_extended_fifo = {
83 	.fifosize		= 128 * 4,
84 	.fifohalfsize		= 64 * 4,
85 	.datalength_bits	= 16,
86 	.pwrreg_powerup		= MCI_PWR_UP,
87 };
88 
89 static struct variant_data variant_u300 = {
90 	.fifosize		= 16 * 4,
91 	.fifohalfsize		= 8 * 4,
92 	.clkreg_enable		= MCI_ST_U300_HWFCEN,
93 	.datalength_bits	= 16,
94 	.sdio			= true,
95 	.pwrreg_powerup		= MCI_PWR_ON,
96 	.signal_direction	= true,
97 };
98 
99 static struct variant_data variant_nomadik = {
100 	.fifosize		= 16 * 4,
101 	.fifohalfsize		= 8 * 4,
102 	.clkreg			= MCI_CLK_ENABLE,
103 	.datalength_bits	= 24,
104 	.sdio			= true,
105 	.st_clkdiv		= true,
106 	.pwrreg_powerup		= MCI_PWR_ON,
107 	.signal_direction	= true,
108 };
109 
110 static struct variant_data variant_ux500 = {
111 	.fifosize		= 30 * 4,
112 	.fifohalfsize		= 8 * 4,
113 	.clkreg			= MCI_CLK_ENABLE,
114 	.clkreg_enable		= MCI_ST_UX500_HWFCEN,
115 	.datalength_bits	= 24,
116 	.sdio			= true,
117 	.st_clkdiv		= true,
118 	.pwrreg_powerup		= MCI_PWR_ON,
119 	.signal_direction	= true,
120 };
121 
122 static struct variant_data variant_ux500v2 = {
123 	.fifosize		= 30 * 4,
124 	.fifohalfsize		= 8 * 4,
125 	.clkreg			= MCI_CLK_ENABLE,
126 	.clkreg_enable		= MCI_ST_UX500_HWFCEN,
127 	.datalength_bits	= 24,
128 	.sdio			= true,
129 	.st_clkdiv		= true,
130 	.blksz_datactrl16	= true,
131 	.pwrreg_powerup		= MCI_PWR_ON,
132 	.signal_direction	= true,
133 };
134 
135 /*
136  * This must be called with host->lock held
137  */
138 static void mmci_write_clkreg(struct mmci_host *host, u32 clk)
139 {
140 	if (host->clk_reg != clk) {
141 		host->clk_reg = clk;
142 		writel(clk, host->base + MMCICLOCK);
143 	}
144 }
145 
146 /*
147  * This must be called with host->lock held
148  */
149 static void mmci_write_pwrreg(struct mmci_host *host, u32 pwr)
150 {
151 	if (host->pwr_reg != pwr) {
152 		host->pwr_reg = pwr;
153 		writel(pwr, host->base + MMCIPOWER);
154 	}
155 }
156 
157 /*
158  * This must be called with host->lock held
159  */
160 static void mmci_set_clkreg(struct mmci_host *host, unsigned int desired)
161 {
162 	struct variant_data *variant = host->variant;
163 	u32 clk = variant->clkreg;
164 
165 	if (desired) {
166 		if (desired >= host->mclk) {
167 			clk = MCI_CLK_BYPASS;
168 			if (variant->st_clkdiv)
169 				clk |= MCI_ST_UX500_NEG_EDGE;
170 			host->cclk = host->mclk;
171 		} else if (variant->st_clkdiv) {
172 			/*
173 			 * DB8500 TRM says f = mclk / (clkdiv + 2)
174 			 * => clkdiv = (mclk / f) - 2
175 			 * Round the divider up so we don't exceed the max
176 			 * frequency
177 			 */
178 			clk = DIV_ROUND_UP(host->mclk, desired) - 2;
179 			if (clk >= 256)
180 				clk = 255;
181 			host->cclk = host->mclk / (clk + 2);
182 		} else {
183 			/*
184 			 * PL180 TRM says f = mclk / (2 * (clkdiv + 1))
185 			 * => clkdiv = mclk / (2 * f) - 1
186 			 */
187 			clk = host->mclk / (2 * desired) - 1;
188 			if (clk >= 256)
189 				clk = 255;
190 			host->cclk = host->mclk / (2 * (clk + 1));
191 		}
192 
193 		clk |= variant->clkreg_enable;
194 		clk |= MCI_CLK_ENABLE;
195 		/* This hasn't proven to be worthwhile */
196 		/* clk |= MCI_CLK_PWRSAVE; */
197 	}
198 
199 	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_4)
200 		clk |= MCI_4BIT_BUS;
201 	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_8)
202 		clk |= MCI_ST_8BIT_BUS;
203 
204 	mmci_write_clkreg(host, clk);
205 }
206 
207 static void
208 mmci_request_end(struct mmci_host *host, struct mmc_request *mrq)
209 {
210 	writel(0, host->base + MMCICOMMAND);
211 
212 	BUG_ON(host->data);
213 
214 	host->mrq = NULL;
215 	host->cmd = NULL;
216 
217 	mmc_request_done(host->mmc, mrq);
218 
219 	pm_runtime_mark_last_busy(mmc_dev(host->mmc));
220 	pm_runtime_put_autosuspend(mmc_dev(host->mmc));
221 }
222 
223 static void mmci_set_mask1(struct mmci_host *host, unsigned int mask)
224 {
225 	void __iomem *base = host->base;
226 
227 	if (host->singleirq) {
228 		unsigned int mask0 = readl(base + MMCIMASK0);
229 
230 		mask0 &= ~MCI_IRQ1MASK;
231 		mask0 |= mask;
232 
233 		writel(mask0, base + MMCIMASK0);
234 	}
235 
236 	writel(mask, base + MMCIMASK1);
237 }
238 
239 static void mmci_stop_data(struct mmci_host *host)
240 {
241 	writel(0, host->base + MMCIDATACTRL);
242 	mmci_set_mask1(host, 0);
243 	host->data = NULL;
244 }
245 
246 static void mmci_init_sg(struct mmci_host *host, struct mmc_data *data)
247 {
248 	unsigned int flags = SG_MITER_ATOMIC;
249 
250 	if (data->flags & MMC_DATA_READ)
251 		flags |= SG_MITER_TO_SG;
252 	else
253 		flags |= SG_MITER_FROM_SG;
254 
255 	sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
256 }
257 
258 /*
259  * All the DMA operation mode stuff goes inside this ifdef.
260  * This assumes that you have a generic DMA device interface,
261  * no custom DMA interfaces are supported.
262  */
263 #ifdef CONFIG_DMA_ENGINE
264 static void __devinit mmci_dma_setup(struct mmci_host *host)
265 {
266 	struct mmci_platform_data *plat = host->plat;
267 	const char *rxname, *txname;
268 	dma_cap_mask_t mask;
269 
270 	if (!plat || !plat->dma_filter) {
271 		dev_info(mmc_dev(host->mmc), "no DMA platform data\n");
272 		return;
273 	}
274 
275 	/* initialize pre request cookie */
276 	host->next_data.cookie = 1;
277 
278 	/* Try to acquire a generic DMA engine slave channel */
279 	dma_cap_zero(mask);
280 	dma_cap_set(DMA_SLAVE, mask);
281 
282 	/*
283 	 * If only an RX channel is specified, the driver will
284 	 * attempt to use it bidirectionally, however if it is
285 	 * is specified but cannot be located, DMA will be disabled.
286 	 */
287 	if (plat->dma_rx_param) {
288 		host->dma_rx_channel = dma_request_channel(mask,
289 							   plat->dma_filter,
290 							   plat->dma_rx_param);
291 		/* E.g if no DMA hardware is present */
292 		if (!host->dma_rx_channel)
293 			dev_err(mmc_dev(host->mmc), "no RX DMA channel\n");
294 	}
295 
296 	if (plat->dma_tx_param) {
297 		host->dma_tx_channel = dma_request_channel(mask,
298 							   plat->dma_filter,
299 							   plat->dma_tx_param);
300 		if (!host->dma_tx_channel)
301 			dev_warn(mmc_dev(host->mmc), "no TX DMA channel\n");
302 	} else {
303 		host->dma_tx_channel = host->dma_rx_channel;
304 	}
305 
306 	if (host->dma_rx_channel)
307 		rxname = dma_chan_name(host->dma_rx_channel);
308 	else
309 		rxname = "none";
310 
311 	if (host->dma_tx_channel)
312 		txname = dma_chan_name(host->dma_tx_channel);
313 	else
314 		txname = "none";
315 
316 	dev_info(mmc_dev(host->mmc), "DMA channels RX %s, TX %s\n",
317 		 rxname, txname);
318 
319 	/*
320 	 * Limit the maximum segment size in any SG entry according to
321 	 * the parameters of the DMA engine device.
322 	 */
323 	if (host->dma_tx_channel) {
324 		struct device *dev = host->dma_tx_channel->device->dev;
325 		unsigned int max_seg_size = dma_get_max_seg_size(dev);
326 
327 		if (max_seg_size < host->mmc->max_seg_size)
328 			host->mmc->max_seg_size = max_seg_size;
329 	}
330 	if (host->dma_rx_channel) {
331 		struct device *dev = host->dma_rx_channel->device->dev;
332 		unsigned int max_seg_size = dma_get_max_seg_size(dev);
333 
334 		if (max_seg_size < host->mmc->max_seg_size)
335 			host->mmc->max_seg_size = max_seg_size;
336 	}
337 }
338 
339 /*
340  * This is used in __devinit or __devexit so inline it
341  * so it can be discarded.
342  */
343 static inline void mmci_dma_release(struct mmci_host *host)
344 {
345 	struct mmci_platform_data *plat = host->plat;
346 
347 	if (host->dma_rx_channel)
348 		dma_release_channel(host->dma_rx_channel);
349 	if (host->dma_tx_channel && plat->dma_tx_param)
350 		dma_release_channel(host->dma_tx_channel);
351 	host->dma_rx_channel = host->dma_tx_channel = NULL;
352 }
353 
354 static void mmci_dma_unmap(struct mmci_host *host, struct mmc_data *data)
355 {
356 	struct dma_chan *chan = host->dma_current;
357 	enum dma_data_direction dir;
358 	u32 status;
359 	int i;
360 
361 	/* Wait up to 1ms for the DMA to complete */
362 	for (i = 0; ; i++) {
363 		status = readl(host->base + MMCISTATUS);
364 		if (!(status & MCI_RXDATAAVLBLMASK) || i >= 100)
365 			break;
366 		udelay(10);
367 	}
368 
369 	/*
370 	 * Check to see whether we still have some data left in the FIFO -
371 	 * this catches DMA controllers which are unable to monitor the
372 	 * DMALBREQ and DMALSREQ signals while allowing us to DMA to non-
373 	 * contiguous buffers.  On TX, we'll get a FIFO underrun error.
374 	 */
375 	if (status & MCI_RXDATAAVLBLMASK) {
376 		dmaengine_terminate_all(chan);
377 		if (!data->error)
378 			data->error = -EIO;
379 	}
380 
381 	if (data->flags & MMC_DATA_WRITE) {
382 		dir = DMA_TO_DEVICE;
383 	} else {
384 		dir = DMA_FROM_DEVICE;
385 	}
386 
387 	if (!data->host_cookie)
388 		dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, dir);
389 
390 	/*
391 	 * Use of DMA with scatter-gather is impossible.
392 	 * Give up with DMA and switch back to PIO mode.
393 	 */
394 	if (status & MCI_RXDATAAVLBLMASK) {
395 		dev_err(mmc_dev(host->mmc), "buggy DMA detected. Taking evasive action.\n");
396 		mmci_dma_release(host);
397 	}
398 }
399 
400 static void mmci_dma_data_error(struct mmci_host *host)
401 {
402 	dev_err(mmc_dev(host->mmc), "error during DMA transfer!\n");
403 	dmaengine_terminate_all(host->dma_current);
404 }
405 
406 static int mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data,
407 			      struct mmci_host_next *next)
408 {
409 	struct variant_data *variant = host->variant;
410 	struct dma_slave_config conf = {
411 		.src_addr = host->phybase + MMCIFIFO,
412 		.dst_addr = host->phybase + MMCIFIFO,
413 		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
414 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
415 		.src_maxburst = variant->fifohalfsize >> 2, /* # of words */
416 		.dst_maxburst = variant->fifohalfsize >> 2, /* # of words */
417 		.device_fc = false,
418 	};
419 	struct dma_chan *chan;
420 	struct dma_device *device;
421 	struct dma_async_tx_descriptor *desc;
422 	enum dma_data_direction buffer_dirn;
423 	int nr_sg;
424 
425 	/* Check if next job is already prepared */
426 	if (data->host_cookie && !next &&
427 	    host->dma_current && host->dma_desc_current)
428 		return 0;
429 
430 	if (!next) {
431 		host->dma_current = NULL;
432 		host->dma_desc_current = NULL;
433 	}
434 
435 	if (data->flags & MMC_DATA_READ) {
436 		conf.direction = DMA_DEV_TO_MEM;
437 		buffer_dirn = DMA_FROM_DEVICE;
438 		chan = host->dma_rx_channel;
439 	} else {
440 		conf.direction = DMA_MEM_TO_DEV;
441 		buffer_dirn = DMA_TO_DEVICE;
442 		chan = host->dma_tx_channel;
443 	}
444 
445 	/* If there's no DMA channel, fall back to PIO */
446 	if (!chan)
447 		return -EINVAL;
448 
449 	/* If less than or equal to the fifo size, don't bother with DMA */
450 	if (data->blksz * data->blocks <= variant->fifosize)
451 		return -EINVAL;
452 
453 	device = chan->device;
454 	nr_sg = dma_map_sg(device->dev, data->sg, data->sg_len, buffer_dirn);
455 	if (nr_sg == 0)
456 		return -EINVAL;
457 
458 	dmaengine_slave_config(chan, &conf);
459 	desc = dmaengine_prep_slave_sg(chan, data->sg, nr_sg,
460 					    conf.direction, DMA_CTRL_ACK);
461 	if (!desc)
462 		goto unmap_exit;
463 
464 	if (next) {
465 		next->dma_chan = chan;
466 		next->dma_desc = desc;
467 	} else {
468 		host->dma_current = chan;
469 		host->dma_desc_current = desc;
470 	}
471 
472 	return 0;
473 
474  unmap_exit:
475 	if (!next)
476 		dmaengine_terminate_all(chan);
477 	dma_unmap_sg(device->dev, data->sg, data->sg_len, buffer_dirn);
478 	return -ENOMEM;
479 }
480 
481 static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
482 {
483 	int ret;
484 	struct mmc_data *data = host->data;
485 
486 	ret = mmci_dma_prep_data(host, host->data, NULL);
487 	if (ret)
488 		return ret;
489 
490 	/* Okay, go for it. */
491 	dev_vdbg(mmc_dev(host->mmc),
492 		 "Submit MMCI DMA job, sglen %d blksz %04x blks %04x flags %08x\n",
493 		 data->sg_len, data->blksz, data->blocks, data->flags);
494 	dmaengine_submit(host->dma_desc_current);
495 	dma_async_issue_pending(host->dma_current);
496 
497 	datactrl |= MCI_DPSM_DMAENABLE;
498 
499 	/* Trigger the DMA transfer */
500 	writel(datactrl, host->base + MMCIDATACTRL);
501 
502 	/*
503 	 * Let the MMCI say when the data is ended and it's time
504 	 * to fire next DMA request. When that happens, MMCI will
505 	 * call mmci_data_end()
506 	 */
507 	writel(readl(host->base + MMCIMASK0) | MCI_DATAENDMASK,
508 	       host->base + MMCIMASK0);
509 	return 0;
510 }
511 
512 static void mmci_get_next_data(struct mmci_host *host, struct mmc_data *data)
513 {
514 	struct mmci_host_next *next = &host->next_data;
515 
516 	if (data->host_cookie && data->host_cookie != next->cookie) {
517 		pr_warning("[%s] invalid cookie: data->host_cookie %d"
518 		       " host->next_data.cookie %d\n",
519 		       __func__, data->host_cookie, host->next_data.cookie);
520 		data->host_cookie = 0;
521 	}
522 
523 	if (!data->host_cookie)
524 		return;
525 
526 	host->dma_desc_current = next->dma_desc;
527 	host->dma_current = next->dma_chan;
528 
529 	next->dma_desc = NULL;
530 	next->dma_chan = NULL;
531 }
532 
533 static void mmci_pre_request(struct mmc_host *mmc, struct mmc_request *mrq,
534 			     bool is_first_req)
535 {
536 	struct mmci_host *host = mmc_priv(mmc);
537 	struct mmc_data *data = mrq->data;
538 	struct mmci_host_next *nd = &host->next_data;
539 
540 	if (!data)
541 		return;
542 
543 	if (data->host_cookie) {
544 		data->host_cookie = 0;
545 		return;
546 	}
547 
548 	/* if config for dma */
549 	if (((data->flags & MMC_DATA_WRITE) && host->dma_tx_channel) ||
550 	    ((data->flags & MMC_DATA_READ) && host->dma_rx_channel)) {
551 		if (mmci_dma_prep_data(host, data, nd))
552 			data->host_cookie = 0;
553 		else
554 			data->host_cookie = ++nd->cookie < 0 ? 1 : nd->cookie;
555 	}
556 }
557 
558 static void mmci_post_request(struct mmc_host *mmc, struct mmc_request *mrq,
559 			      int err)
560 {
561 	struct mmci_host *host = mmc_priv(mmc);
562 	struct mmc_data *data = mrq->data;
563 	struct dma_chan *chan;
564 	enum dma_data_direction dir;
565 
566 	if (!data)
567 		return;
568 
569 	if (data->flags & MMC_DATA_READ) {
570 		dir = DMA_FROM_DEVICE;
571 		chan = host->dma_rx_channel;
572 	} else {
573 		dir = DMA_TO_DEVICE;
574 		chan = host->dma_tx_channel;
575 	}
576 
577 
578 	/* if config for dma */
579 	if (chan) {
580 		if (err)
581 			dmaengine_terminate_all(chan);
582 		if (data->host_cookie)
583 			dma_unmap_sg(mmc_dev(host->mmc), data->sg,
584 				     data->sg_len, dir);
585 		mrq->data->host_cookie = 0;
586 	}
587 }
588 
589 #else
590 /* Blank functions if the DMA engine is not available */
591 static void mmci_get_next_data(struct mmci_host *host, struct mmc_data *data)
592 {
593 }
594 static inline void mmci_dma_setup(struct mmci_host *host)
595 {
596 }
597 
598 static inline void mmci_dma_release(struct mmci_host *host)
599 {
600 }
601 
602 static inline void mmci_dma_unmap(struct mmci_host *host, struct mmc_data *data)
603 {
604 }
605 
606 static inline void mmci_dma_data_error(struct mmci_host *host)
607 {
608 }
609 
610 static inline int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl)
611 {
612 	return -ENOSYS;
613 }
614 
615 #define mmci_pre_request NULL
616 #define mmci_post_request NULL
617 
618 #endif
619 
620 static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
621 {
622 	struct variant_data *variant = host->variant;
623 	unsigned int datactrl, timeout, irqmask;
624 	unsigned long long clks;
625 	void __iomem *base;
626 	int blksz_bits;
627 
628 	dev_dbg(mmc_dev(host->mmc), "blksz %04x blks %04x flags %08x\n",
629 		data->blksz, data->blocks, data->flags);
630 
631 	host->data = data;
632 	host->size = data->blksz * data->blocks;
633 	data->bytes_xfered = 0;
634 
635 	clks = (unsigned long long)data->timeout_ns * host->cclk;
636 	do_div(clks, 1000000000UL);
637 
638 	timeout = data->timeout_clks + (unsigned int)clks;
639 
640 	base = host->base;
641 	writel(timeout, base + MMCIDATATIMER);
642 	writel(host->size, base + MMCIDATALENGTH);
643 
644 	blksz_bits = ffs(data->blksz) - 1;
645 	BUG_ON(1 << blksz_bits != data->blksz);
646 
647 	if (variant->blksz_datactrl16)
648 		datactrl = MCI_DPSM_ENABLE | (data->blksz << 16);
649 	else
650 		datactrl = MCI_DPSM_ENABLE | blksz_bits << 4;
651 
652 	if (data->flags & MMC_DATA_READ)
653 		datactrl |= MCI_DPSM_DIRECTION;
654 
655 	/* The ST Micro variants has a special bit to enable SDIO */
656 	if (variant->sdio && host->mmc->card)
657 		if (mmc_card_sdio(host->mmc->card))
658 			datactrl |= MCI_ST_DPSM_SDIOEN;
659 
660 	/*
661 	 * Attempt to use DMA operation mode, if this
662 	 * should fail, fall back to PIO mode
663 	 */
664 	if (!mmci_dma_start_data(host, datactrl))
665 		return;
666 
667 	/* IRQ mode, map the SG list for CPU reading/writing */
668 	mmci_init_sg(host, data);
669 
670 	if (data->flags & MMC_DATA_READ) {
671 		irqmask = MCI_RXFIFOHALFFULLMASK;
672 
673 		/*
674 		 * If we have less than the fifo 'half-full' threshold to
675 		 * transfer, trigger a PIO interrupt as soon as any data
676 		 * is available.
677 		 */
678 		if (host->size < variant->fifohalfsize)
679 			irqmask |= MCI_RXDATAAVLBLMASK;
680 	} else {
681 		/*
682 		 * We don't actually need to include "FIFO empty" here
683 		 * since its implicit in "FIFO half empty".
684 		 */
685 		irqmask = MCI_TXFIFOHALFEMPTYMASK;
686 	}
687 
688 	writel(datactrl, base + MMCIDATACTRL);
689 	writel(readl(base + MMCIMASK0) & ~MCI_DATAENDMASK, base + MMCIMASK0);
690 	mmci_set_mask1(host, irqmask);
691 }
692 
693 static void
694 mmci_start_command(struct mmci_host *host, struct mmc_command *cmd, u32 c)
695 {
696 	void __iomem *base = host->base;
697 
698 	dev_dbg(mmc_dev(host->mmc), "op %02x arg %08x flags %08x\n",
699 	    cmd->opcode, cmd->arg, cmd->flags);
700 
701 	if (readl(base + MMCICOMMAND) & MCI_CPSM_ENABLE) {
702 		writel(0, base + MMCICOMMAND);
703 		udelay(1);
704 	}
705 
706 	c |= cmd->opcode | MCI_CPSM_ENABLE;
707 	if (cmd->flags & MMC_RSP_PRESENT) {
708 		if (cmd->flags & MMC_RSP_136)
709 			c |= MCI_CPSM_LONGRSP;
710 		c |= MCI_CPSM_RESPONSE;
711 	}
712 	if (/*interrupt*/0)
713 		c |= MCI_CPSM_INTERRUPT;
714 
715 	host->cmd = cmd;
716 
717 	writel(cmd->arg, base + MMCIARGUMENT);
718 	writel(c, base + MMCICOMMAND);
719 }
720 
721 static void
722 mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
723 	      unsigned int status)
724 {
725 	/* First check for errors */
726 	if (status & (MCI_DATACRCFAIL|MCI_DATATIMEOUT|MCI_STARTBITERR|
727 		      MCI_TXUNDERRUN|MCI_RXOVERRUN)) {
728 		u32 remain, success;
729 
730 		/* Terminate the DMA transfer */
731 		if (dma_inprogress(host))
732 			mmci_dma_data_error(host);
733 
734 		/*
735 		 * Calculate how far we are into the transfer.  Note that
736 		 * the data counter gives the number of bytes transferred
737 		 * on the MMC bus, not on the host side.  On reads, this
738 		 * can be as much as a FIFO-worth of data ahead.  This
739 		 * matters for FIFO overruns only.
740 		 */
741 		remain = readl(host->base + MMCIDATACNT);
742 		success = data->blksz * data->blocks - remain;
743 
744 		dev_dbg(mmc_dev(host->mmc), "MCI ERROR IRQ, status 0x%08x at 0x%08x\n",
745 			status, success);
746 		if (status & MCI_DATACRCFAIL) {
747 			/* Last block was not successful */
748 			success -= 1;
749 			data->error = -EILSEQ;
750 		} else if (status & MCI_DATATIMEOUT) {
751 			data->error = -ETIMEDOUT;
752 		} else if (status & MCI_STARTBITERR) {
753 			data->error = -ECOMM;
754 		} else if (status & MCI_TXUNDERRUN) {
755 			data->error = -EIO;
756 		} else if (status & MCI_RXOVERRUN) {
757 			if (success > host->variant->fifosize)
758 				success -= host->variant->fifosize;
759 			else
760 				success = 0;
761 			data->error = -EIO;
762 		}
763 		data->bytes_xfered = round_down(success, data->blksz);
764 	}
765 
766 	if (status & MCI_DATABLOCKEND)
767 		dev_err(mmc_dev(host->mmc), "stray MCI_DATABLOCKEND interrupt\n");
768 
769 	if (status & MCI_DATAEND || data->error) {
770 		if (dma_inprogress(host))
771 			mmci_dma_unmap(host, data);
772 		mmci_stop_data(host);
773 
774 		if (!data->error)
775 			/* The error clause is handled above, success! */
776 			data->bytes_xfered = data->blksz * data->blocks;
777 
778 		if (!data->stop) {
779 			mmci_request_end(host, data->mrq);
780 		} else {
781 			mmci_start_command(host, data->stop, 0);
782 		}
783 	}
784 }
785 
786 static void
787 mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,
788 	     unsigned int status)
789 {
790 	void __iomem *base = host->base;
791 
792 	host->cmd = NULL;
793 
794 	if (status & MCI_CMDTIMEOUT) {
795 		cmd->error = -ETIMEDOUT;
796 	} else if (status & MCI_CMDCRCFAIL && cmd->flags & MMC_RSP_CRC) {
797 		cmd->error = -EILSEQ;
798 	} else {
799 		cmd->resp[0] = readl(base + MMCIRESPONSE0);
800 		cmd->resp[1] = readl(base + MMCIRESPONSE1);
801 		cmd->resp[2] = readl(base + MMCIRESPONSE2);
802 		cmd->resp[3] = readl(base + MMCIRESPONSE3);
803 	}
804 
805 	if (!cmd->data || cmd->error) {
806 		if (host->data) {
807 			/* Terminate the DMA transfer */
808 			if (dma_inprogress(host))
809 				mmci_dma_data_error(host);
810 			mmci_stop_data(host);
811 		}
812 		mmci_request_end(host, cmd->mrq);
813 	} else if (!(cmd->data->flags & MMC_DATA_READ)) {
814 		mmci_start_data(host, cmd->data);
815 	}
816 }
817 
818 static int mmci_pio_read(struct mmci_host *host, char *buffer, unsigned int remain)
819 {
820 	void __iomem *base = host->base;
821 	char *ptr = buffer;
822 	u32 status;
823 	int host_remain = host->size;
824 
825 	do {
826 		int count = host_remain - (readl(base + MMCIFIFOCNT) << 2);
827 
828 		if (count > remain)
829 			count = remain;
830 
831 		if (count <= 0)
832 			break;
833 
834 		/*
835 		 * SDIO especially may want to send something that is
836 		 * not divisible by 4 (as opposed to card sectors
837 		 * etc). Therefore make sure to always read the last bytes
838 		 * while only doing full 32-bit reads towards the FIFO.
839 		 */
840 		if (unlikely(count & 0x3)) {
841 			if (count < 4) {
842 				unsigned char buf[4];
843 				readsl(base + MMCIFIFO, buf, 1);
844 				memcpy(ptr, buf, count);
845 			} else {
846 				readsl(base + MMCIFIFO, ptr, count >> 2);
847 				count &= ~0x3;
848 			}
849 		} else {
850 			readsl(base + MMCIFIFO, ptr, count >> 2);
851 		}
852 
853 		ptr += count;
854 		remain -= count;
855 		host_remain -= count;
856 
857 		if (remain == 0)
858 			break;
859 
860 		status = readl(base + MMCISTATUS);
861 	} while (status & MCI_RXDATAAVLBL);
862 
863 	return ptr - buffer;
864 }
865 
866 static int mmci_pio_write(struct mmci_host *host, char *buffer, unsigned int remain, u32 status)
867 {
868 	struct variant_data *variant = host->variant;
869 	void __iomem *base = host->base;
870 	char *ptr = buffer;
871 
872 	do {
873 		unsigned int count, maxcnt;
874 
875 		maxcnt = status & MCI_TXFIFOEMPTY ?
876 			 variant->fifosize : variant->fifohalfsize;
877 		count = min(remain, maxcnt);
878 
879 		/*
880 		 * The ST Micro variant for SDIO transfer sizes
881 		 * less then 8 bytes should have clock H/W flow
882 		 * control disabled.
883 		 */
884 		if (variant->sdio &&
885 		    mmc_card_sdio(host->mmc->card)) {
886 			u32 clk;
887 			if (count < 8)
888 				clk = host->clk_reg & ~variant->clkreg_enable;
889 			else
890 				clk = host->clk_reg | variant->clkreg_enable;
891 
892 			mmci_write_clkreg(host, clk);
893 		}
894 
895 		/*
896 		 * SDIO especially may want to send something that is
897 		 * not divisible by 4 (as opposed to card sectors
898 		 * etc), and the FIFO only accept full 32-bit writes.
899 		 * So compensate by adding +3 on the count, a single
900 		 * byte become a 32bit write, 7 bytes will be two
901 		 * 32bit writes etc.
902 		 */
903 		writesl(base + MMCIFIFO, ptr, (count + 3) >> 2);
904 
905 		ptr += count;
906 		remain -= count;
907 
908 		if (remain == 0)
909 			break;
910 
911 		status = readl(base + MMCISTATUS);
912 	} while (status & MCI_TXFIFOHALFEMPTY);
913 
914 	return ptr - buffer;
915 }
916 
917 /*
918  * PIO data transfer IRQ handler.
919  */
920 static irqreturn_t mmci_pio_irq(int irq, void *dev_id)
921 {
922 	struct mmci_host *host = dev_id;
923 	struct sg_mapping_iter *sg_miter = &host->sg_miter;
924 	struct variant_data *variant = host->variant;
925 	void __iomem *base = host->base;
926 	unsigned long flags;
927 	u32 status;
928 
929 	status = readl(base + MMCISTATUS);
930 
931 	dev_dbg(mmc_dev(host->mmc), "irq1 (pio) %08x\n", status);
932 
933 	local_irq_save(flags);
934 
935 	do {
936 		unsigned int remain, len;
937 		char *buffer;
938 
939 		/*
940 		 * For write, we only need to test the half-empty flag
941 		 * here - if the FIFO is completely empty, then by
942 		 * definition it is more than half empty.
943 		 *
944 		 * For read, check for data available.
945 		 */
946 		if (!(status & (MCI_TXFIFOHALFEMPTY|MCI_RXDATAAVLBL)))
947 			break;
948 
949 		if (!sg_miter_next(sg_miter))
950 			break;
951 
952 		buffer = sg_miter->addr;
953 		remain = sg_miter->length;
954 
955 		len = 0;
956 		if (status & MCI_RXACTIVE)
957 			len = mmci_pio_read(host, buffer, remain);
958 		if (status & MCI_TXACTIVE)
959 			len = mmci_pio_write(host, buffer, remain, status);
960 
961 		sg_miter->consumed = len;
962 
963 		host->size -= len;
964 		remain -= len;
965 
966 		if (remain)
967 			break;
968 
969 		status = readl(base + MMCISTATUS);
970 	} while (1);
971 
972 	sg_miter_stop(sg_miter);
973 
974 	local_irq_restore(flags);
975 
976 	/*
977 	 * If we have less than the fifo 'half-full' threshold to transfer,
978 	 * trigger a PIO interrupt as soon as any data is available.
979 	 */
980 	if (status & MCI_RXACTIVE && host->size < variant->fifohalfsize)
981 		mmci_set_mask1(host, MCI_RXDATAAVLBLMASK);
982 
983 	/*
984 	 * If we run out of data, disable the data IRQs; this
985 	 * prevents a race where the FIFO becomes empty before
986 	 * the chip itself has disabled the data path, and
987 	 * stops us racing with our data end IRQ.
988 	 */
989 	if (host->size == 0) {
990 		mmci_set_mask1(host, 0);
991 		writel(readl(base + MMCIMASK0) | MCI_DATAENDMASK, base + MMCIMASK0);
992 	}
993 
994 	return IRQ_HANDLED;
995 }
996 
997 /*
998  * Handle completion of command and data transfers.
999  */
1000 static irqreturn_t mmci_irq(int irq, void *dev_id)
1001 {
1002 	struct mmci_host *host = dev_id;
1003 	u32 status;
1004 	int ret = 0;
1005 
1006 	spin_lock(&host->lock);
1007 
1008 	do {
1009 		struct mmc_command *cmd;
1010 		struct mmc_data *data;
1011 
1012 		status = readl(host->base + MMCISTATUS);
1013 
1014 		if (host->singleirq) {
1015 			if (status & readl(host->base + MMCIMASK1))
1016 				mmci_pio_irq(irq, dev_id);
1017 
1018 			status &= ~MCI_IRQ1MASK;
1019 		}
1020 
1021 		status &= readl(host->base + MMCIMASK0);
1022 		writel(status, host->base + MMCICLEAR);
1023 
1024 		dev_dbg(mmc_dev(host->mmc), "irq0 (data+cmd) %08x\n", status);
1025 
1026 		data = host->data;
1027 		if (status & (MCI_DATACRCFAIL|MCI_DATATIMEOUT|MCI_STARTBITERR|
1028 			      MCI_TXUNDERRUN|MCI_RXOVERRUN|MCI_DATAEND|
1029 			      MCI_DATABLOCKEND) && data)
1030 			mmci_data_irq(host, data, status);
1031 
1032 		cmd = host->cmd;
1033 		if (status & (MCI_CMDCRCFAIL|MCI_CMDTIMEOUT|MCI_CMDSENT|MCI_CMDRESPEND) && cmd)
1034 			mmci_cmd_irq(host, cmd, status);
1035 
1036 		ret = 1;
1037 	} while (status);
1038 
1039 	spin_unlock(&host->lock);
1040 
1041 	return IRQ_RETVAL(ret);
1042 }
1043 
1044 static void mmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
1045 {
1046 	struct mmci_host *host = mmc_priv(mmc);
1047 	unsigned long flags;
1048 
1049 	WARN_ON(host->mrq != NULL);
1050 
1051 	if (mrq->data && !is_power_of_2(mrq->data->blksz)) {
1052 		dev_err(mmc_dev(mmc), "unsupported block size (%d bytes)\n",
1053 			mrq->data->blksz);
1054 		mrq->cmd->error = -EINVAL;
1055 		mmc_request_done(mmc, mrq);
1056 		return;
1057 	}
1058 
1059 	pm_runtime_get_sync(mmc_dev(mmc));
1060 
1061 	spin_lock_irqsave(&host->lock, flags);
1062 
1063 	host->mrq = mrq;
1064 
1065 	if (mrq->data)
1066 		mmci_get_next_data(host, mrq->data);
1067 
1068 	if (mrq->data && mrq->data->flags & MMC_DATA_READ)
1069 		mmci_start_data(host, mrq->data);
1070 
1071 	mmci_start_command(host, mrq->cmd, 0);
1072 
1073 	spin_unlock_irqrestore(&host->lock, flags);
1074 }
1075 
1076 static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
1077 {
1078 	struct mmci_host *host = mmc_priv(mmc);
1079 	struct variant_data *variant = host->variant;
1080 	u32 pwr = 0;
1081 	unsigned long flags;
1082 	int ret;
1083 
1084 	pm_runtime_get_sync(mmc_dev(mmc));
1085 
1086 	if (host->plat->ios_handler &&
1087 		host->plat->ios_handler(mmc_dev(mmc), ios))
1088 			dev_err(mmc_dev(mmc), "platform ios_handler failed\n");
1089 
1090 	switch (ios->power_mode) {
1091 	case MMC_POWER_OFF:
1092 		if (host->vcc)
1093 			ret = mmc_regulator_set_ocr(mmc, host->vcc, 0);
1094 		break;
1095 	case MMC_POWER_UP:
1096 		if (host->vcc) {
1097 			ret = mmc_regulator_set_ocr(mmc, host->vcc, ios->vdd);
1098 			if (ret) {
1099 				dev_err(mmc_dev(mmc), "unable to set OCR\n");
1100 				/*
1101 				 * The .set_ios() function in the mmc_host_ops
1102 				 * struct return void, and failing to set the
1103 				 * power should be rare so we print an error
1104 				 * and return here.
1105 				 */
1106 				goto out;
1107 			}
1108 		}
1109 		/*
1110 		 * The ST Micro variant doesn't have the PL180s MCI_PWR_UP
1111 		 * and instead uses MCI_PWR_ON so apply whatever value is
1112 		 * configured in the variant data.
1113 		 */
1114 		pwr |= variant->pwrreg_powerup;
1115 
1116 		break;
1117 	case MMC_POWER_ON:
1118 		pwr |= MCI_PWR_ON;
1119 		break;
1120 	}
1121 
1122 	if (variant->signal_direction && ios->power_mode != MMC_POWER_OFF) {
1123 		/*
1124 		 * The ST Micro variant has some additional bits
1125 		 * indicating signal direction for the signals in
1126 		 * the SD/MMC bus and feedback-clock usage.
1127 		 */
1128 		pwr |= host->plat->sigdir;
1129 
1130 		if (ios->bus_width == MMC_BUS_WIDTH_4)
1131 			pwr &= ~MCI_ST_DATA74DIREN;
1132 		else if (ios->bus_width == MMC_BUS_WIDTH_1)
1133 			pwr &= (~MCI_ST_DATA74DIREN &
1134 				~MCI_ST_DATA31DIREN &
1135 				~MCI_ST_DATA2DIREN);
1136 	}
1137 
1138 	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) {
1139 		if (host->hw_designer != AMBA_VENDOR_ST)
1140 			pwr |= MCI_ROD;
1141 		else {
1142 			/*
1143 			 * The ST Micro variant use the ROD bit for something
1144 			 * else and only has OD (Open Drain).
1145 			 */
1146 			pwr |= MCI_OD;
1147 		}
1148 	}
1149 
1150 	spin_lock_irqsave(&host->lock, flags);
1151 
1152 	mmci_set_clkreg(host, ios->clock);
1153 	mmci_write_pwrreg(host, pwr);
1154 
1155 	spin_unlock_irqrestore(&host->lock, flags);
1156 
1157  out:
1158 	pm_runtime_mark_last_busy(mmc_dev(mmc));
1159 	pm_runtime_put_autosuspend(mmc_dev(mmc));
1160 }
1161 
1162 static int mmci_get_ro(struct mmc_host *mmc)
1163 {
1164 	struct mmci_host *host = mmc_priv(mmc);
1165 
1166 	if (host->gpio_wp == -ENOSYS)
1167 		return -ENOSYS;
1168 
1169 	return gpio_get_value_cansleep(host->gpio_wp);
1170 }
1171 
1172 static int mmci_get_cd(struct mmc_host *mmc)
1173 {
1174 	struct mmci_host *host = mmc_priv(mmc);
1175 	struct mmci_platform_data *plat = host->plat;
1176 	unsigned int status;
1177 
1178 	if (host->gpio_cd == -ENOSYS) {
1179 		if (!plat->status)
1180 			return 1; /* Assume always present */
1181 
1182 		status = plat->status(mmc_dev(host->mmc));
1183 	} else
1184 		status = !!gpio_get_value_cansleep(host->gpio_cd)
1185 			^ plat->cd_invert;
1186 
1187 	/*
1188 	 * Use positive logic throughout - status is zero for no card,
1189 	 * non-zero for card inserted.
1190 	 */
1191 	return status;
1192 }
1193 
1194 static irqreturn_t mmci_cd_irq(int irq, void *dev_id)
1195 {
1196 	struct mmci_host *host = dev_id;
1197 
1198 	mmc_detect_change(host->mmc, msecs_to_jiffies(500));
1199 
1200 	return IRQ_HANDLED;
1201 }
1202 
1203 static const struct mmc_host_ops mmci_ops = {
1204 	.request	= mmci_request,
1205 	.pre_req	= mmci_pre_request,
1206 	.post_req	= mmci_post_request,
1207 	.set_ios	= mmci_set_ios,
1208 	.get_ro		= mmci_get_ro,
1209 	.get_cd		= mmci_get_cd,
1210 };
1211 
1212 #ifdef CONFIG_OF
1213 static void mmci_dt_populate_generic_pdata(struct device_node *np,
1214 					struct mmci_platform_data *pdata)
1215 {
1216 	int bus_width = 0;
1217 
1218 	pdata->gpio_wp = of_get_named_gpio(np, "wp-gpios", 0);
1219 	if (!pdata->gpio_wp)
1220 		pdata->gpio_wp = -1;
1221 
1222 	pdata->gpio_cd = of_get_named_gpio(np, "cd-gpios", 0);
1223 	if (!pdata->gpio_cd)
1224 		pdata->gpio_cd = -1;
1225 
1226 	if (of_get_property(np, "cd-inverted", NULL))
1227 		pdata->cd_invert = true;
1228 	else
1229 		pdata->cd_invert = false;
1230 
1231 	of_property_read_u32(np, "max-frequency", &pdata->f_max);
1232 	if (!pdata->f_max)
1233 		pr_warn("%s has no 'max-frequency' property\n", np->full_name);
1234 
1235 	if (of_get_property(np, "mmc-cap-mmc-highspeed", NULL))
1236 		pdata->capabilities |= MMC_CAP_MMC_HIGHSPEED;
1237 	if (of_get_property(np, "mmc-cap-sd-highspeed", NULL))
1238 		pdata->capabilities |= MMC_CAP_SD_HIGHSPEED;
1239 
1240 	of_property_read_u32(np, "bus-width", &bus_width);
1241 	switch (bus_width) {
1242 	case 0 :
1243 		/* No bus-width supplied. */
1244 		break;
1245 	case 4 :
1246 		pdata->capabilities |= MMC_CAP_4_BIT_DATA;
1247 		break;
1248 	case 8 :
1249 		pdata->capabilities |= MMC_CAP_8_BIT_DATA;
1250 		break;
1251 	default :
1252 		pr_warn("%s: Unsupported bus width\n", np->full_name);
1253 	}
1254 }
1255 #else
1256 static void mmci_dt_populate_generic_pdata(struct device_node *np,
1257 					struct mmci_platform_data *pdata)
1258 {
1259 	return;
1260 }
1261 #endif
1262 
1263 static int __devinit mmci_probe(struct amba_device *dev,
1264 	const struct amba_id *id)
1265 {
1266 	struct mmci_platform_data *plat = dev->dev.platform_data;
1267 	struct device_node *np = dev->dev.of_node;
1268 	struct variant_data *variant = id->data;
1269 	struct mmci_host *host;
1270 	struct mmc_host *mmc;
1271 	int ret;
1272 
1273 	/* Must have platform data or Device Tree. */
1274 	if (!plat && !np) {
1275 		dev_err(&dev->dev, "No plat data or DT found\n");
1276 		return -EINVAL;
1277 	}
1278 
1279 	if (np)
1280 		mmci_dt_populate_generic_pdata(np, plat);
1281 
1282 	ret = amba_request_regions(dev, DRIVER_NAME);
1283 	if (ret)
1284 		goto out;
1285 
1286 	mmc = mmc_alloc_host(sizeof(struct mmci_host), &dev->dev);
1287 	if (!mmc) {
1288 		ret = -ENOMEM;
1289 		goto rel_regions;
1290 	}
1291 
1292 	host = mmc_priv(mmc);
1293 	host->mmc = mmc;
1294 
1295 	host->gpio_wp = -ENOSYS;
1296 	host->gpio_cd = -ENOSYS;
1297 	host->gpio_cd_irq = -1;
1298 
1299 	host->hw_designer = amba_manf(dev);
1300 	host->hw_revision = amba_rev(dev);
1301 	dev_dbg(mmc_dev(mmc), "designer ID = 0x%02x\n", host->hw_designer);
1302 	dev_dbg(mmc_dev(mmc), "revision = 0x%01x\n", host->hw_revision);
1303 
1304 	host->clk = clk_get(&dev->dev, NULL);
1305 	if (IS_ERR(host->clk)) {
1306 		ret = PTR_ERR(host->clk);
1307 		host->clk = NULL;
1308 		goto host_free;
1309 	}
1310 
1311 	ret = clk_prepare(host->clk);
1312 	if (ret)
1313 		goto clk_free;
1314 
1315 	ret = clk_enable(host->clk);
1316 	if (ret)
1317 		goto clk_unprep;
1318 
1319 	host->plat = plat;
1320 	host->variant = variant;
1321 	host->mclk = clk_get_rate(host->clk);
1322 	/*
1323 	 * According to the spec, mclk is max 100 MHz,
1324 	 * so we try to adjust the clock down to this,
1325 	 * (if possible).
1326 	 */
1327 	if (host->mclk > 100000000) {
1328 		ret = clk_set_rate(host->clk, 100000000);
1329 		if (ret < 0)
1330 			goto clk_disable;
1331 		host->mclk = clk_get_rate(host->clk);
1332 		dev_dbg(mmc_dev(mmc), "eventual mclk rate: %u Hz\n",
1333 			host->mclk);
1334 	}
1335 	host->phybase = dev->res.start;
1336 	host->base = ioremap(dev->res.start, resource_size(&dev->res));
1337 	if (!host->base) {
1338 		ret = -ENOMEM;
1339 		goto clk_disable;
1340 	}
1341 
1342 	mmc->ops = &mmci_ops;
1343 	/*
1344 	 * The ARM and ST versions of the block have slightly different
1345 	 * clock divider equations which means that the minimum divider
1346 	 * differs too.
1347 	 */
1348 	if (variant->st_clkdiv)
1349 		mmc->f_min = DIV_ROUND_UP(host->mclk, 257);
1350 	else
1351 		mmc->f_min = DIV_ROUND_UP(host->mclk, 512);
1352 	/*
1353 	 * If the platform data supplies a maximum operating
1354 	 * frequency, this takes precedence. Else, we fall back
1355 	 * to using the module parameter, which has a (low)
1356 	 * default value in case it is not specified. Either
1357 	 * value must not exceed the clock rate into the block,
1358 	 * of course.
1359 	 */
1360 	if (plat->f_max)
1361 		mmc->f_max = min(host->mclk, plat->f_max);
1362 	else
1363 		mmc->f_max = min(host->mclk, fmax);
1364 	dev_dbg(mmc_dev(mmc), "clocking block at %u Hz\n", mmc->f_max);
1365 
1366 #ifdef CONFIG_REGULATOR
1367 	/* If we're using the regulator framework, try to fetch a regulator */
1368 	host->vcc = regulator_get(&dev->dev, "vmmc");
1369 	if (IS_ERR(host->vcc))
1370 		host->vcc = NULL;
1371 	else {
1372 		int mask = mmc_regulator_get_ocrmask(host->vcc);
1373 
1374 		if (mask < 0)
1375 			dev_err(&dev->dev, "error getting OCR mask (%d)\n",
1376 				mask);
1377 		else {
1378 			host->mmc->ocr_avail = (u32) mask;
1379 			if (plat->ocr_mask)
1380 				dev_warn(&dev->dev,
1381 				 "Provided ocr_mask/setpower will not be used "
1382 				 "(using regulator instead)\n");
1383 		}
1384 	}
1385 #endif
1386 	/* Fall back to platform data if no regulator is found */
1387 	if (host->vcc == NULL)
1388 		mmc->ocr_avail = plat->ocr_mask;
1389 	mmc->caps = plat->capabilities;
1390 	mmc->caps2 = plat->capabilities2;
1391 
1392 	/*
1393 	 * We can do SGIO
1394 	 */
1395 	mmc->max_segs = NR_SG;
1396 
1397 	/*
1398 	 * Since only a certain number of bits are valid in the data length
1399 	 * register, we must ensure that we don't exceed 2^num-1 bytes in a
1400 	 * single request.
1401 	 */
1402 	mmc->max_req_size = (1 << variant->datalength_bits) - 1;
1403 
1404 	/*
1405 	 * Set the maximum segment size.  Since we aren't doing DMA
1406 	 * (yet) we are only limited by the data length register.
1407 	 */
1408 	mmc->max_seg_size = mmc->max_req_size;
1409 
1410 	/*
1411 	 * Block size can be up to 2048 bytes, but must be a power of two.
1412 	 */
1413 	mmc->max_blk_size = 1 << 11;
1414 
1415 	/*
1416 	 * Limit the number of blocks transferred so that we don't overflow
1417 	 * the maximum request size.
1418 	 */
1419 	mmc->max_blk_count = mmc->max_req_size >> 11;
1420 
1421 	spin_lock_init(&host->lock);
1422 
1423 	writel(0, host->base + MMCIMASK0);
1424 	writel(0, host->base + MMCIMASK1);
1425 	writel(0xfff, host->base + MMCICLEAR);
1426 
1427 	if (gpio_is_valid(plat->gpio_cd)) {
1428 		ret = gpio_request(plat->gpio_cd, DRIVER_NAME " (cd)");
1429 		if (ret == 0)
1430 			ret = gpio_direction_input(plat->gpio_cd);
1431 		if (ret == 0)
1432 			host->gpio_cd = plat->gpio_cd;
1433 		else if (ret != -ENOSYS)
1434 			goto err_gpio_cd;
1435 
1436 		/*
1437 		 * A gpio pin that will detect cards when inserted and removed
1438 		 * will most likely want to trigger on the edges if it is
1439 		 * 0 when ejected and 1 when inserted (or mutatis mutandis
1440 		 * for the inverted case) so we request triggers on both
1441 		 * edges.
1442 		 */
1443 		ret = request_any_context_irq(gpio_to_irq(plat->gpio_cd),
1444 				mmci_cd_irq,
1445 				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
1446 				DRIVER_NAME " (cd)", host);
1447 		if (ret >= 0)
1448 			host->gpio_cd_irq = gpio_to_irq(plat->gpio_cd);
1449 	}
1450 	if (gpio_is_valid(plat->gpio_wp)) {
1451 		ret = gpio_request(plat->gpio_wp, DRIVER_NAME " (wp)");
1452 		if (ret == 0)
1453 			ret = gpio_direction_input(plat->gpio_wp);
1454 		if (ret == 0)
1455 			host->gpio_wp = plat->gpio_wp;
1456 		else if (ret != -ENOSYS)
1457 			goto err_gpio_wp;
1458 	}
1459 
1460 	if ((host->plat->status || host->gpio_cd != -ENOSYS)
1461 	    && host->gpio_cd_irq < 0)
1462 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1463 
1464 	ret = request_irq(dev->irq[0], mmci_irq, IRQF_SHARED, DRIVER_NAME " (cmd)", host);
1465 	if (ret)
1466 		goto unmap;
1467 
1468 	if (!dev->irq[1])
1469 		host->singleirq = true;
1470 	else {
1471 		ret = request_irq(dev->irq[1], mmci_pio_irq, IRQF_SHARED,
1472 				  DRIVER_NAME " (pio)", host);
1473 		if (ret)
1474 			goto irq0_free;
1475 	}
1476 
1477 	writel(MCI_IRQENABLE, host->base + MMCIMASK0);
1478 
1479 	amba_set_drvdata(dev, mmc);
1480 
1481 	dev_info(&dev->dev, "%s: PL%03x manf %x rev%u at 0x%08llx irq %d,%d (pio)\n",
1482 		 mmc_hostname(mmc), amba_part(dev), amba_manf(dev),
1483 		 amba_rev(dev), (unsigned long long)dev->res.start,
1484 		 dev->irq[0], dev->irq[1]);
1485 
1486 	mmci_dma_setup(host);
1487 
1488 	pm_runtime_set_autosuspend_delay(&dev->dev, 50);
1489 	pm_runtime_use_autosuspend(&dev->dev);
1490 	pm_runtime_put(&dev->dev);
1491 
1492 	mmc_add_host(mmc);
1493 
1494 	return 0;
1495 
1496  irq0_free:
1497 	free_irq(dev->irq[0], host);
1498  unmap:
1499 	if (host->gpio_wp != -ENOSYS)
1500 		gpio_free(host->gpio_wp);
1501  err_gpio_wp:
1502 	if (host->gpio_cd_irq >= 0)
1503 		free_irq(host->gpio_cd_irq, host);
1504 	if (host->gpio_cd != -ENOSYS)
1505 		gpio_free(host->gpio_cd);
1506  err_gpio_cd:
1507 	iounmap(host->base);
1508  clk_disable:
1509 	clk_disable(host->clk);
1510  clk_unprep:
1511 	clk_unprepare(host->clk);
1512  clk_free:
1513 	clk_put(host->clk);
1514  host_free:
1515 	mmc_free_host(mmc);
1516  rel_regions:
1517 	amba_release_regions(dev);
1518  out:
1519 	return ret;
1520 }
1521 
1522 static int __devexit mmci_remove(struct amba_device *dev)
1523 {
1524 	struct mmc_host *mmc = amba_get_drvdata(dev);
1525 
1526 	amba_set_drvdata(dev, NULL);
1527 
1528 	if (mmc) {
1529 		struct mmci_host *host = mmc_priv(mmc);
1530 
1531 		/*
1532 		 * Undo pm_runtime_put() in probe.  We use the _sync
1533 		 * version here so that we can access the primecell.
1534 		 */
1535 		pm_runtime_get_sync(&dev->dev);
1536 
1537 		mmc_remove_host(mmc);
1538 
1539 		writel(0, host->base + MMCIMASK0);
1540 		writel(0, host->base + MMCIMASK1);
1541 
1542 		writel(0, host->base + MMCICOMMAND);
1543 		writel(0, host->base + MMCIDATACTRL);
1544 
1545 		mmci_dma_release(host);
1546 		free_irq(dev->irq[0], host);
1547 		if (!host->singleirq)
1548 			free_irq(dev->irq[1], host);
1549 
1550 		if (host->gpio_wp != -ENOSYS)
1551 			gpio_free(host->gpio_wp);
1552 		if (host->gpio_cd_irq >= 0)
1553 			free_irq(host->gpio_cd_irq, host);
1554 		if (host->gpio_cd != -ENOSYS)
1555 			gpio_free(host->gpio_cd);
1556 
1557 		iounmap(host->base);
1558 		clk_disable(host->clk);
1559 		clk_unprepare(host->clk);
1560 		clk_put(host->clk);
1561 
1562 		if (host->vcc)
1563 			mmc_regulator_set_ocr(mmc, host->vcc, 0);
1564 		regulator_put(host->vcc);
1565 
1566 		mmc_free_host(mmc);
1567 
1568 		amba_release_regions(dev);
1569 	}
1570 
1571 	return 0;
1572 }
1573 
1574 #ifdef CONFIG_SUSPEND
1575 static int mmci_suspend(struct device *dev)
1576 {
1577 	struct amba_device *adev = to_amba_device(dev);
1578 	struct mmc_host *mmc = amba_get_drvdata(adev);
1579 	int ret = 0;
1580 
1581 	if (mmc) {
1582 		struct mmci_host *host = mmc_priv(mmc);
1583 
1584 		ret = mmc_suspend_host(mmc);
1585 		if (ret == 0) {
1586 			pm_runtime_get_sync(dev);
1587 			writel(0, host->base + MMCIMASK0);
1588 		}
1589 	}
1590 
1591 	return ret;
1592 }
1593 
1594 static int mmci_resume(struct device *dev)
1595 {
1596 	struct amba_device *adev = to_amba_device(dev);
1597 	struct mmc_host *mmc = amba_get_drvdata(adev);
1598 	int ret = 0;
1599 
1600 	if (mmc) {
1601 		struct mmci_host *host = mmc_priv(mmc);
1602 
1603 		writel(MCI_IRQENABLE, host->base + MMCIMASK0);
1604 		pm_runtime_put(dev);
1605 
1606 		ret = mmc_resume_host(mmc);
1607 	}
1608 
1609 	return ret;
1610 }
1611 #endif
1612 
1613 static const struct dev_pm_ops mmci_dev_pm_ops = {
1614 	SET_SYSTEM_SLEEP_PM_OPS(mmci_suspend, mmci_resume)
1615 };
1616 
1617 static struct amba_id mmci_ids[] = {
1618 	{
1619 		.id	= 0x00041180,
1620 		.mask	= 0xff0fffff,
1621 		.data	= &variant_arm,
1622 	},
1623 	{
1624 		.id	= 0x01041180,
1625 		.mask	= 0xff0fffff,
1626 		.data	= &variant_arm_extended_fifo,
1627 	},
1628 	{
1629 		.id	= 0x00041181,
1630 		.mask	= 0x000fffff,
1631 		.data	= &variant_arm,
1632 	},
1633 	/* ST Micro variants */
1634 	{
1635 		.id     = 0x00180180,
1636 		.mask   = 0x00ffffff,
1637 		.data	= &variant_u300,
1638 	},
1639 	{
1640 		.id     = 0x10180180,
1641 		.mask   = 0xf0ffffff,
1642 		.data	= &variant_nomadik,
1643 	},
1644 	{
1645 		.id     = 0x00280180,
1646 		.mask   = 0x00ffffff,
1647 		.data	= &variant_u300,
1648 	},
1649 	{
1650 		.id     = 0x00480180,
1651 		.mask   = 0xf0ffffff,
1652 		.data	= &variant_ux500,
1653 	},
1654 	{
1655 		.id     = 0x10480180,
1656 		.mask   = 0xf0ffffff,
1657 		.data	= &variant_ux500v2,
1658 	},
1659 	{ 0, 0 },
1660 };
1661 
1662 MODULE_DEVICE_TABLE(amba, mmci_ids);
1663 
1664 static struct amba_driver mmci_driver = {
1665 	.drv		= {
1666 		.name	= DRIVER_NAME,
1667 		.pm	= &mmci_dev_pm_ops,
1668 	},
1669 	.probe		= mmci_probe,
1670 	.remove		= __devexit_p(mmci_remove),
1671 	.id_table	= mmci_ids,
1672 };
1673 
1674 module_amba_driver(mmci_driver);
1675 
1676 module_param(fmax, uint, 0444);
1677 
1678 MODULE_DESCRIPTION("ARM PrimeCell PL180/181 Multimedia Card Interface driver");
1679 MODULE_LICENSE("GPL");
1680