xref: /openbmc/linux/drivers/mmc/host/mmci.c (revision f42b3800)
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  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #include <linux/module.h>
11 #include <linux/moduleparam.h>
12 #include <linux/init.h>
13 #include <linux/ioport.h>
14 #include <linux/device.h>
15 #include <linux/interrupt.h>
16 #include <linux/delay.h>
17 #include <linux/err.h>
18 #include <linux/highmem.h>
19 #include <linux/log2.h>
20 #include <linux/mmc/host.h>
21 #include <linux/amba/bus.h>
22 #include <linux/clk.h>
23 #include <linux/scatterlist.h>
24 
25 #include <asm/cacheflush.h>
26 #include <asm/div64.h>
27 #include <asm/io.h>
28 #include <asm/sizes.h>
29 #include <asm/mach/mmc.h>
30 
31 #include "mmci.h"
32 
33 #define DRIVER_NAME "mmci-pl18x"
34 
35 #define DBG(host,fmt,args...)	\
36 	pr_debug("%s: %s: " fmt, mmc_hostname(host->mmc), __func__ , args)
37 
38 static unsigned int fmax = 515633;
39 
40 static void
41 mmci_request_end(struct mmci_host *host, struct mmc_request *mrq)
42 {
43 	writel(0, host->base + MMCICOMMAND);
44 
45 	BUG_ON(host->data);
46 
47 	host->mrq = NULL;
48 	host->cmd = NULL;
49 
50 	if (mrq->data)
51 		mrq->data->bytes_xfered = host->data_xfered;
52 
53 	/*
54 	 * Need to drop the host lock here; mmc_request_done may call
55 	 * back into the driver...
56 	 */
57 	spin_unlock(&host->lock);
58 	mmc_request_done(host->mmc, mrq);
59 	spin_lock(&host->lock);
60 }
61 
62 static void mmci_stop_data(struct mmci_host *host)
63 {
64 	writel(0, host->base + MMCIDATACTRL);
65 	writel(0, host->base + MMCIMASK1);
66 	host->data = NULL;
67 }
68 
69 static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
70 {
71 	unsigned int datactrl, timeout, irqmask;
72 	unsigned long long clks;
73 	void __iomem *base;
74 	int blksz_bits;
75 
76 	DBG(host, "blksz %04x blks %04x flags %08x\n",
77 	    data->blksz, data->blocks, data->flags);
78 
79 	host->data = data;
80 	host->size = data->blksz;
81 	host->data_xfered = 0;
82 
83 	mmci_init_sg(host, data);
84 
85 	clks = (unsigned long long)data->timeout_ns * host->cclk;
86 	do_div(clks, 1000000000UL);
87 
88 	timeout = data->timeout_clks + (unsigned int)clks;
89 
90 	base = host->base;
91 	writel(timeout, base + MMCIDATATIMER);
92 	writel(host->size, base + MMCIDATALENGTH);
93 
94 	blksz_bits = ffs(data->blksz) - 1;
95 	BUG_ON(1 << blksz_bits != data->blksz);
96 
97 	datactrl = MCI_DPSM_ENABLE | blksz_bits << 4;
98 	if (data->flags & MMC_DATA_READ) {
99 		datactrl |= MCI_DPSM_DIRECTION;
100 		irqmask = MCI_RXFIFOHALFFULLMASK;
101 
102 		/*
103 		 * If we have less than a FIFOSIZE of bytes to transfer,
104 		 * trigger a PIO interrupt as soon as any data is available.
105 		 */
106 		if (host->size < MCI_FIFOSIZE)
107 			irqmask |= MCI_RXDATAAVLBLMASK;
108 	} else {
109 		/*
110 		 * We don't actually need to include "FIFO empty" here
111 		 * since its implicit in "FIFO half empty".
112 		 */
113 		irqmask = MCI_TXFIFOHALFEMPTYMASK;
114 	}
115 
116 	writel(datactrl, base + MMCIDATACTRL);
117 	writel(readl(base + MMCIMASK0) & ~MCI_DATAENDMASK, base + MMCIMASK0);
118 	writel(irqmask, base + MMCIMASK1);
119 }
120 
121 static void
122 mmci_start_command(struct mmci_host *host, struct mmc_command *cmd, u32 c)
123 {
124 	void __iomem *base = host->base;
125 
126 	DBG(host, "op %02x arg %08x flags %08x\n",
127 	    cmd->opcode, cmd->arg, cmd->flags);
128 
129 	if (readl(base + MMCICOMMAND) & MCI_CPSM_ENABLE) {
130 		writel(0, base + MMCICOMMAND);
131 		udelay(1);
132 	}
133 
134 	c |= cmd->opcode | MCI_CPSM_ENABLE;
135 	if (cmd->flags & MMC_RSP_PRESENT) {
136 		if (cmd->flags & MMC_RSP_136)
137 			c |= MCI_CPSM_LONGRSP;
138 		c |= MCI_CPSM_RESPONSE;
139 	}
140 	if (/*interrupt*/0)
141 		c |= MCI_CPSM_INTERRUPT;
142 
143 	host->cmd = cmd;
144 
145 	writel(cmd->arg, base + MMCIARGUMENT);
146 	writel(c, base + MMCICOMMAND);
147 }
148 
149 static void
150 mmci_data_irq(struct mmci_host *host, struct mmc_data *data,
151 	      unsigned int status)
152 {
153 	if (status & MCI_DATABLOCKEND) {
154 		host->data_xfered += data->blksz;
155 	}
156 	if (status & (MCI_DATACRCFAIL|MCI_DATATIMEOUT|MCI_TXUNDERRUN|MCI_RXOVERRUN)) {
157 		if (status & MCI_DATACRCFAIL)
158 			data->error = -EILSEQ;
159 		else if (status & MCI_DATATIMEOUT)
160 			data->error = -ETIMEDOUT;
161 		else if (status & (MCI_TXUNDERRUN|MCI_RXOVERRUN))
162 			data->error = -EIO;
163 		status |= MCI_DATAEND;
164 
165 		/*
166 		 * We hit an error condition.  Ensure that any data
167 		 * partially written to a page is properly coherent.
168 		 */
169 		if (host->sg_len && data->flags & MMC_DATA_READ)
170 			flush_dcache_page(sg_page(host->sg_ptr));
171 	}
172 	if (status & MCI_DATAEND) {
173 		mmci_stop_data(host);
174 
175 		if (!data->stop) {
176 			mmci_request_end(host, data->mrq);
177 		} else {
178 			mmci_start_command(host, data->stop, 0);
179 		}
180 	}
181 }
182 
183 static void
184 mmci_cmd_irq(struct mmci_host *host, struct mmc_command *cmd,
185 	     unsigned int status)
186 {
187 	void __iomem *base = host->base;
188 
189 	host->cmd = NULL;
190 
191 	cmd->resp[0] = readl(base + MMCIRESPONSE0);
192 	cmd->resp[1] = readl(base + MMCIRESPONSE1);
193 	cmd->resp[2] = readl(base + MMCIRESPONSE2);
194 	cmd->resp[3] = readl(base + MMCIRESPONSE3);
195 
196 	if (status & MCI_CMDTIMEOUT) {
197 		cmd->error = -ETIMEDOUT;
198 	} else if (status & MCI_CMDCRCFAIL && cmd->flags & MMC_RSP_CRC) {
199 		cmd->error = -EILSEQ;
200 	}
201 
202 	if (!cmd->data || cmd->error) {
203 		if (host->data)
204 			mmci_stop_data(host);
205 		mmci_request_end(host, cmd->mrq);
206 	} else if (!(cmd->data->flags & MMC_DATA_READ)) {
207 		mmci_start_data(host, cmd->data);
208 	}
209 }
210 
211 static int mmci_pio_read(struct mmci_host *host, char *buffer, unsigned int remain)
212 {
213 	void __iomem *base = host->base;
214 	char *ptr = buffer;
215 	u32 status;
216 
217 	do {
218 		int count = host->size - (readl(base + MMCIFIFOCNT) << 2);
219 
220 		if (count > remain)
221 			count = remain;
222 
223 		if (count <= 0)
224 			break;
225 
226 		readsl(base + MMCIFIFO, ptr, count >> 2);
227 
228 		ptr += count;
229 		remain -= count;
230 
231 		if (remain == 0)
232 			break;
233 
234 		status = readl(base + MMCISTATUS);
235 	} while (status & MCI_RXDATAAVLBL);
236 
237 	return ptr - buffer;
238 }
239 
240 static int mmci_pio_write(struct mmci_host *host, char *buffer, unsigned int remain, u32 status)
241 {
242 	void __iomem *base = host->base;
243 	char *ptr = buffer;
244 
245 	do {
246 		unsigned int count, maxcnt;
247 
248 		maxcnt = status & MCI_TXFIFOEMPTY ? MCI_FIFOSIZE : MCI_FIFOHALFSIZE;
249 		count = min(remain, maxcnt);
250 
251 		writesl(base + MMCIFIFO, ptr, count >> 2);
252 
253 		ptr += count;
254 		remain -= count;
255 
256 		if (remain == 0)
257 			break;
258 
259 		status = readl(base + MMCISTATUS);
260 	} while (status & MCI_TXFIFOHALFEMPTY);
261 
262 	return ptr - buffer;
263 }
264 
265 /*
266  * PIO data transfer IRQ handler.
267  */
268 static irqreturn_t mmci_pio_irq(int irq, void *dev_id)
269 {
270 	struct mmci_host *host = dev_id;
271 	void __iomem *base = host->base;
272 	u32 status;
273 
274 	status = readl(base + MMCISTATUS);
275 
276 	DBG(host, "irq1 %08x\n", status);
277 
278 	do {
279 		unsigned long flags;
280 		unsigned int remain, len;
281 		char *buffer;
282 
283 		/*
284 		 * For write, we only need to test the half-empty flag
285 		 * here - if the FIFO is completely empty, then by
286 		 * definition it is more than half empty.
287 		 *
288 		 * For read, check for data available.
289 		 */
290 		if (!(status & (MCI_TXFIFOHALFEMPTY|MCI_RXDATAAVLBL)))
291 			break;
292 
293 		/*
294 		 * Map the current scatter buffer.
295 		 */
296 		buffer = mmci_kmap_atomic(host, &flags) + host->sg_off;
297 		remain = host->sg_ptr->length - host->sg_off;
298 
299 		len = 0;
300 		if (status & MCI_RXACTIVE)
301 			len = mmci_pio_read(host, buffer, remain);
302 		if (status & MCI_TXACTIVE)
303 			len = mmci_pio_write(host, buffer, remain, status);
304 
305 		/*
306 		 * Unmap the buffer.
307 		 */
308 		mmci_kunmap_atomic(host, buffer, &flags);
309 
310 		host->sg_off += len;
311 		host->size -= len;
312 		remain -= len;
313 
314 		if (remain)
315 			break;
316 
317 		/*
318 		 * If we were reading, and we have completed this
319 		 * page, ensure that the data cache is coherent.
320 		 */
321 		if (status & MCI_RXACTIVE)
322 			flush_dcache_page(sg_page(host->sg_ptr));
323 
324 		if (!mmci_next_sg(host))
325 			break;
326 
327 		status = readl(base + MMCISTATUS);
328 	} while (1);
329 
330 	/*
331 	 * If we're nearing the end of the read, switch to
332 	 * "any data available" mode.
333 	 */
334 	if (status & MCI_RXACTIVE && host->size < MCI_FIFOSIZE)
335 		writel(MCI_RXDATAAVLBLMASK, base + MMCIMASK1);
336 
337 	/*
338 	 * If we run out of data, disable the data IRQs; this
339 	 * prevents a race where the FIFO becomes empty before
340 	 * the chip itself has disabled the data path, and
341 	 * stops us racing with our data end IRQ.
342 	 */
343 	if (host->size == 0) {
344 		writel(0, base + MMCIMASK1);
345 		writel(readl(base + MMCIMASK0) | MCI_DATAENDMASK, base + MMCIMASK0);
346 	}
347 
348 	return IRQ_HANDLED;
349 }
350 
351 /*
352  * Handle completion of command and data transfers.
353  */
354 static irqreturn_t mmci_irq(int irq, void *dev_id)
355 {
356 	struct mmci_host *host = dev_id;
357 	u32 status;
358 	int ret = 0;
359 
360 	spin_lock(&host->lock);
361 
362 	do {
363 		struct mmc_command *cmd;
364 		struct mmc_data *data;
365 
366 		status = readl(host->base + MMCISTATUS);
367 		status &= readl(host->base + MMCIMASK0);
368 		writel(status, host->base + MMCICLEAR);
369 
370 		DBG(host, "irq0 %08x\n", status);
371 
372 		data = host->data;
373 		if (status & (MCI_DATACRCFAIL|MCI_DATATIMEOUT|MCI_TXUNDERRUN|
374 			      MCI_RXOVERRUN|MCI_DATAEND|MCI_DATABLOCKEND) && data)
375 			mmci_data_irq(host, data, status);
376 
377 		cmd = host->cmd;
378 		if (status & (MCI_CMDCRCFAIL|MCI_CMDTIMEOUT|MCI_CMDSENT|MCI_CMDRESPEND) && cmd)
379 			mmci_cmd_irq(host, cmd, status);
380 
381 		ret = 1;
382 	} while (status);
383 
384 	spin_unlock(&host->lock);
385 
386 	return IRQ_RETVAL(ret);
387 }
388 
389 static void mmci_request(struct mmc_host *mmc, struct mmc_request *mrq)
390 {
391 	struct mmci_host *host = mmc_priv(mmc);
392 
393 	WARN_ON(host->mrq != NULL);
394 
395 	if (mrq->data && !is_power_of_2(mrq->data->blksz)) {
396 		printk(KERN_ERR "%s: Unsupported block size (%d bytes)\n",
397 			mmc_hostname(mmc), mrq->data->blksz);
398 		mrq->cmd->error = -EINVAL;
399 		mmc_request_done(mmc, mrq);
400 		return;
401 	}
402 
403 	spin_lock_irq(&host->lock);
404 
405 	host->mrq = mrq;
406 
407 	if (mrq->data && mrq->data->flags & MMC_DATA_READ)
408 		mmci_start_data(host, mrq->data);
409 
410 	mmci_start_command(host, mrq->cmd, 0);
411 
412 	spin_unlock_irq(&host->lock);
413 }
414 
415 static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
416 {
417 	struct mmci_host *host = mmc_priv(mmc);
418 	u32 clk = 0, pwr = 0;
419 
420 	if (ios->clock) {
421 		if (ios->clock >= host->mclk) {
422 			clk = MCI_CLK_BYPASS;
423 			host->cclk = host->mclk;
424 		} else {
425 			clk = host->mclk / (2 * ios->clock) - 1;
426 			if (clk > 256)
427 				clk = 255;
428 			host->cclk = host->mclk / (2 * (clk + 1));
429 		}
430 		clk |= MCI_CLK_ENABLE;
431 	}
432 
433 	if (host->plat->translate_vdd)
434 		pwr |= host->plat->translate_vdd(mmc_dev(mmc), ios->vdd);
435 
436 	switch (ios->power_mode) {
437 	case MMC_POWER_OFF:
438 		break;
439 	case MMC_POWER_UP:
440 		pwr |= MCI_PWR_UP;
441 		break;
442 	case MMC_POWER_ON:
443 		pwr |= MCI_PWR_ON;
444 		break;
445 	}
446 
447 	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN)
448 		pwr |= MCI_ROD;
449 
450 	writel(clk, host->base + MMCICLOCK);
451 
452 	if (host->pwr != pwr) {
453 		host->pwr = pwr;
454 		writel(pwr, host->base + MMCIPOWER);
455 	}
456 }
457 
458 static const struct mmc_host_ops mmci_ops = {
459 	.request	= mmci_request,
460 	.set_ios	= mmci_set_ios,
461 };
462 
463 static void mmci_check_status(unsigned long data)
464 {
465 	struct mmci_host *host = (struct mmci_host *)data;
466 	unsigned int status;
467 
468 	status = host->plat->status(mmc_dev(host->mmc));
469 	if (status ^ host->oldstat)
470 		mmc_detect_change(host->mmc, 0);
471 
472 	host->oldstat = status;
473 	mod_timer(&host->timer, jiffies + HZ);
474 }
475 
476 static int mmci_probe(struct amba_device *dev, void *id)
477 {
478 	struct mmc_platform_data *plat = dev->dev.platform_data;
479 	struct mmci_host *host;
480 	struct mmc_host *mmc;
481 	int ret;
482 
483 	/* must have platform data */
484 	if (!plat) {
485 		ret = -EINVAL;
486 		goto out;
487 	}
488 
489 	ret = amba_request_regions(dev, DRIVER_NAME);
490 	if (ret)
491 		goto out;
492 
493 	mmc = mmc_alloc_host(sizeof(struct mmci_host), &dev->dev);
494 	if (!mmc) {
495 		ret = -ENOMEM;
496 		goto rel_regions;
497 	}
498 
499 	host = mmc_priv(mmc);
500 	host->clk = clk_get(&dev->dev, "MCLK");
501 	if (IS_ERR(host->clk)) {
502 		ret = PTR_ERR(host->clk);
503 		host->clk = NULL;
504 		goto host_free;
505 	}
506 
507 	ret = clk_enable(host->clk);
508 	if (ret)
509 		goto clk_free;
510 
511 	host->plat = plat;
512 	host->mclk = clk_get_rate(host->clk);
513 	host->mmc = mmc;
514 	host->base = ioremap(dev->res.start, SZ_4K);
515 	if (!host->base) {
516 		ret = -ENOMEM;
517 		goto clk_disable;
518 	}
519 
520 	mmc->ops = &mmci_ops;
521 	mmc->f_min = (host->mclk + 511) / 512;
522 	mmc->f_max = min(host->mclk, fmax);
523 	mmc->ocr_avail = plat->ocr_mask;
524 	mmc->caps = MMC_CAP_MULTIWRITE;
525 
526 	/*
527 	 * We can do SGIO
528 	 */
529 	mmc->max_hw_segs = 16;
530 	mmc->max_phys_segs = NR_SG;
531 
532 	/*
533 	 * Since we only have a 16-bit data length register, we must
534 	 * ensure that we don't exceed 2^16-1 bytes in a single request.
535 	 */
536 	mmc->max_req_size = 65535;
537 
538 	/*
539 	 * Set the maximum segment size.  Since we aren't doing DMA
540 	 * (yet) we are only limited by the data length register.
541 	 */
542 	mmc->max_seg_size = mmc->max_req_size;
543 
544 	/*
545 	 * Block size can be up to 2048 bytes, but must be a power of two.
546 	 */
547 	mmc->max_blk_size = 2048;
548 
549 	/*
550 	 * No limit on the number of blocks transferred.
551 	 */
552 	mmc->max_blk_count = mmc->max_req_size;
553 
554 	spin_lock_init(&host->lock);
555 
556 	writel(0, host->base + MMCIMASK0);
557 	writel(0, host->base + MMCIMASK1);
558 	writel(0xfff, host->base + MMCICLEAR);
559 
560 	ret = request_irq(dev->irq[0], mmci_irq, IRQF_SHARED, DRIVER_NAME " (cmd)", host);
561 	if (ret)
562 		goto unmap;
563 
564 	ret = request_irq(dev->irq[1], mmci_pio_irq, IRQF_SHARED, DRIVER_NAME " (pio)", host);
565 	if (ret)
566 		goto irq0_free;
567 
568 	writel(MCI_IRQENABLE, host->base + MMCIMASK0);
569 
570 	amba_set_drvdata(dev, mmc);
571 
572 	mmc_add_host(mmc);
573 
574 	printk(KERN_INFO "%s: MMCI rev %x cfg %02x at 0x%016llx irq %d,%d\n",
575 		mmc_hostname(mmc), amba_rev(dev), amba_config(dev),
576 		(unsigned long long)dev->res.start, dev->irq[0], dev->irq[1]);
577 
578 	init_timer(&host->timer);
579 	host->timer.data = (unsigned long)host;
580 	host->timer.function = mmci_check_status;
581 	host->timer.expires = jiffies + HZ;
582 	add_timer(&host->timer);
583 
584 	return 0;
585 
586  irq0_free:
587 	free_irq(dev->irq[0], host);
588  unmap:
589 	iounmap(host->base);
590  clk_disable:
591 	clk_disable(host->clk);
592  clk_free:
593 	clk_put(host->clk);
594  host_free:
595 	mmc_free_host(mmc);
596  rel_regions:
597 	amba_release_regions(dev);
598  out:
599 	return ret;
600 }
601 
602 static int mmci_remove(struct amba_device *dev)
603 {
604 	struct mmc_host *mmc = amba_get_drvdata(dev);
605 
606 	amba_set_drvdata(dev, NULL);
607 
608 	if (mmc) {
609 		struct mmci_host *host = mmc_priv(mmc);
610 
611 		del_timer_sync(&host->timer);
612 
613 		mmc_remove_host(mmc);
614 
615 		writel(0, host->base + MMCIMASK0);
616 		writel(0, host->base + MMCIMASK1);
617 
618 		writel(0, host->base + MMCICOMMAND);
619 		writel(0, host->base + MMCIDATACTRL);
620 
621 		free_irq(dev->irq[0], host);
622 		free_irq(dev->irq[1], host);
623 
624 		iounmap(host->base);
625 		clk_disable(host->clk);
626 		clk_put(host->clk);
627 
628 		mmc_free_host(mmc);
629 
630 		amba_release_regions(dev);
631 	}
632 
633 	return 0;
634 }
635 
636 #ifdef CONFIG_PM
637 static int mmci_suspend(struct amba_device *dev, pm_message_t state)
638 {
639 	struct mmc_host *mmc = amba_get_drvdata(dev);
640 	int ret = 0;
641 
642 	if (mmc) {
643 		struct mmci_host *host = mmc_priv(mmc);
644 
645 		ret = mmc_suspend_host(mmc, state);
646 		if (ret == 0)
647 			writel(0, host->base + MMCIMASK0);
648 	}
649 
650 	return ret;
651 }
652 
653 static int mmci_resume(struct amba_device *dev)
654 {
655 	struct mmc_host *mmc = amba_get_drvdata(dev);
656 	int ret = 0;
657 
658 	if (mmc) {
659 		struct mmci_host *host = mmc_priv(mmc);
660 
661 		writel(MCI_IRQENABLE, host->base + MMCIMASK0);
662 
663 		ret = mmc_resume_host(mmc);
664 	}
665 
666 	return ret;
667 }
668 #else
669 #define mmci_suspend	NULL
670 #define mmci_resume	NULL
671 #endif
672 
673 static struct amba_id mmci_ids[] = {
674 	{
675 		.id	= 0x00041180,
676 		.mask	= 0x000fffff,
677 	},
678 	{
679 		.id	= 0x00041181,
680 		.mask	= 0x000fffff,
681 	},
682 	{ 0, 0 },
683 };
684 
685 static struct amba_driver mmci_driver = {
686 	.drv		= {
687 		.name	= DRIVER_NAME,
688 	},
689 	.probe		= mmci_probe,
690 	.remove		= mmci_remove,
691 	.suspend	= mmci_suspend,
692 	.resume		= mmci_resume,
693 	.id_table	= mmci_ids,
694 };
695 
696 static int __init mmci_init(void)
697 {
698 	return amba_driver_register(&mmci_driver);
699 }
700 
701 static void __exit mmci_exit(void)
702 {
703 	amba_driver_unregister(&mmci_driver);
704 }
705 
706 module_init(mmci_init);
707 module_exit(mmci_exit);
708 module_param(fmax, uint, 0444);
709 
710 MODULE_DESCRIPTION("ARM PrimeCell PL180/181 Multimedia Card Interface driver");
711 MODULE_LICENSE("GPL");
712