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1// SPDX-License-Identifier: GPL-2.02/*3 * bcm2835 sdhost driver.4 *5 * The 2835 has two SD controllers: The Arasan sdhci controller6 * (supported by the iproc driver) and a custom sdhost controller7 * (supported by this driver).8 *9 * The sdhci controller supports both sdcard and sdio.  The sdhost10 * controller supports the sdcard only, but has better performance.11 * Also note that the rpi3 has sdio wifi, so driving the sdcard with12 * the sdhost controller allows to use the sdhci controller for wifi13 * support.14 *15 * The configuration is done by devicetree via pin muxing.  Both16 * SD controller are available on the same pins (2 pin groups = pin 2217 * to 27 + pin 48 to 53).  So it's possible to use both SD controllers18 * at the same time with different pin groups.19 *20 * Author:      Phil Elwell <phil@raspberrypi.org>21 *              Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.22 *23 * Based on24 *  mmc-bcm2835.c by Gellert Weisz25 * which is, in turn, based on26 *  sdhci-bcm2708.c by Broadcom27 *  sdhci-bcm2835.c by Stephen Warren and Oleksandr Tymoshenko28 *  sdhci.c and sdhci-pci.c by Pierre Ossman29 */30#include <linux/clk.h>31#include <linux/delay.h>32#include <linux/device.h>33#include <linux/dmaengine.h>34#include <linux/dma-mapping.h>35#include <linux/err.h>36#include <linux/highmem.h>37#include <linux/interrupt.h>38#include <linux/io.h>39#include <linux/iopoll.h>40#include <linux/module.h>41#include <linux/of_address.h>42#include <linux/of_irq.h>43#include <linux/platform_device.h>44#include <linux/scatterlist.h>45#include <linux/time.h>46#include <linux/workqueue.h>47 48#include <linux/mmc/host.h>49#include <linux/mmc/mmc.h>50#include <linux/mmc/sd.h>51 52#define SDCMD  0x00 /* Command to SD card              - 16 R/W */53#define SDARG  0x04 /* Argument to SD card             - 32 R/W */54#define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */55#define SDCDIV 0x0c /* Start value for clock divider   - 11 R/W */56#define SDRSP0 0x10 /* SD card response (31:0)         - 32 R   */57#define SDRSP1 0x14 /* SD card response (63:32)        - 32 R   */58#define SDRSP2 0x18 /* SD card response (95:64)        - 32 R   */59#define SDRSP3 0x1c /* SD card response (127:96)       - 32 R   */60#define SDHSTS 0x20 /* SD host status                  - 11 R/W */61#define SDVDD  0x30 /* SD card power control           -  1 R/W */62#define SDEDM  0x34 /* Emergency Debug Mode            - 13 R/W */63#define SDHCFG 0x38 /* Host configuration              -  2 R/W */64#define SDHBCT 0x3c /* Host byte count (debug)         - 32 R/W */65#define SDDATA 0x40 /* Data to/from SD card            - 32 R/W */66#define SDHBLC 0x50 /* Host block count (SDIO/SDHC)    -  9 R/W */67 68#define SDCMD_NEW_FLAG			0x800069#define SDCMD_FAIL_FLAG			0x400070#define SDCMD_BUSYWAIT			0x80071#define SDCMD_NO_RESPONSE		0x40072#define SDCMD_LONG_RESPONSE		0x20073#define SDCMD_WRITE_CMD			0x8074#define SDCMD_READ_CMD			0x4075#define SDCMD_CMD_MASK			0x3f76 77#define SDCDIV_MAX_CDIV			0x7ff78 79#define SDHSTS_BUSY_IRPT		0x40080#define SDHSTS_BLOCK_IRPT		0x20081#define SDHSTS_SDIO_IRPT		0x10082#define SDHSTS_REW_TIME_OUT		0x8083#define SDHSTS_CMD_TIME_OUT		0x4084#define SDHSTS_CRC16_ERROR		0x2085#define SDHSTS_CRC7_ERROR		0x1086#define SDHSTS_FIFO_ERROR		0x0887/* Reserved */88/* Reserved */89#define SDHSTS_DATA_FLAG		0x0190 91#define SDHSTS_TRANSFER_ERROR_MASK	(SDHSTS_CRC7_ERROR | \92					 SDHSTS_CRC16_ERROR | \93					 SDHSTS_REW_TIME_OUT | \94					 SDHSTS_FIFO_ERROR)95 96#define SDHSTS_ERROR_MASK		(SDHSTS_CMD_TIME_OUT | \97					 SDHSTS_TRANSFER_ERROR_MASK)98 99#define SDHCFG_BUSY_IRPT_EN	BIT(10)100#define SDHCFG_BLOCK_IRPT_EN	BIT(8)101#define SDHCFG_SDIO_IRPT_EN	BIT(5)102#define SDHCFG_DATA_IRPT_EN	BIT(4)103#define SDHCFG_SLOW_CARD	BIT(3)104#define SDHCFG_WIDE_EXT_BUS	BIT(2)105#define SDHCFG_WIDE_INT_BUS	BIT(1)106#define SDHCFG_REL_CMD_LINE	BIT(0)107 108#define SDVDD_POWER_OFF		0109#define SDVDD_POWER_ON		1110 111#define SDEDM_FORCE_DATA_MODE	BIT(19)112#define SDEDM_CLOCK_PULSE	BIT(20)113#define SDEDM_BYPASS		BIT(21)114 115#define SDEDM_WRITE_THRESHOLD_SHIFT	9116#define SDEDM_READ_THRESHOLD_SHIFT	14117#define SDEDM_THRESHOLD_MASK		0x1f118 119#define SDEDM_FSM_MASK		0xf120#define SDEDM_FSM_IDENTMODE	0x0121#define SDEDM_FSM_DATAMODE	0x1122#define SDEDM_FSM_READDATA	0x2123#define SDEDM_FSM_WRITEDATA	0x3124#define SDEDM_FSM_READWAIT	0x4125#define SDEDM_FSM_READCRC	0x5126#define SDEDM_FSM_WRITECRC	0x6127#define SDEDM_FSM_WRITEWAIT1	0x7128#define SDEDM_FSM_POWERDOWN	0x8129#define SDEDM_FSM_POWERUP	0x9130#define SDEDM_FSM_WRITESTART1	0xa131#define SDEDM_FSM_WRITESTART2	0xb132#define SDEDM_FSM_GENPULSES	0xc133#define SDEDM_FSM_WRITEWAIT2	0xd134#define SDEDM_FSM_STARTPOWDOWN	0xf135 136#define SDDATA_FIFO_WORDS	16137 138#define FIFO_READ_THRESHOLD	4139#define FIFO_WRITE_THRESHOLD	4140#define SDDATA_FIFO_PIO_BURST	8141 142#define PIO_THRESHOLD	1  /* Maximum block count for PIO (0 = always DMA) */143 144struct bcm2835_host {145	spinlock_t		lock;146	struct mutex		mutex;147 148	void __iomem		*ioaddr;149	u32			phys_addr;150 151	struct platform_device	*pdev;152 153	int			clock;		/* Current clock speed */154	unsigned int		max_clk;	/* Max possible freq */155	struct work_struct	dma_work;156	struct delayed_work	timeout_work;	/* Timer for timeouts */157	struct sg_mapping_iter	sg_miter;	/* SG state for PIO */158	unsigned int		blocks;		/* remaining PIO blocks */159	int			irq;		/* Device IRQ */160 161	u32			ns_per_fifo_word;162 163	/* cached registers */164	u32			hcfg;165	u32			cdiv;166 167	struct mmc_request	*mrq;		/* Current request */168	struct mmc_command	*cmd;		/* Current command */169	struct mmc_data		*data;		/* Current data request */170	bool			data_complete:1;/* Data finished before cmd */171	bool			use_busy:1;	/* Wait for busy interrupt */172	bool			use_sbc:1;	/* Send CMD23 */173 174	/* for threaded irq handler */175	bool			irq_block;176	bool			irq_busy;177	bool			irq_data;178 179	/* DMA part */180	struct dma_chan		*dma_chan_rxtx;181	struct dma_chan		*dma_chan;182	struct dma_slave_config dma_cfg_rx;183	struct dma_slave_config dma_cfg_tx;184	struct dma_async_tx_descriptor	*dma_desc;185	u32			dma_dir;186	u32			drain_words;187	struct page		*drain_page;188	u32			drain_offset;189	bool			use_dma;190};191 192static void bcm2835_dumpcmd(struct bcm2835_host *host, struct mmc_command *cmd,193			    const char *label)194{195	struct device *dev = &host->pdev->dev;196 197	if (!cmd)198		return;199 200	dev_dbg(dev, "%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n",201		(cmd == host->cmd) ? '>' : ' ',202		label, cmd->opcode, cmd->arg, cmd->flags,203		cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3],204		cmd->error);205}206 207static void bcm2835_dumpregs(struct bcm2835_host *host)208{209	struct mmc_request *mrq = host->mrq;210	struct device *dev = &host->pdev->dev;211 212	if (mrq) {213		bcm2835_dumpcmd(host, mrq->sbc, "sbc");214		bcm2835_dumpcmd(host, mrq->cmd, "cmd");215		if (mrq->data) {216			dev_dbg(dev, "data blocks %x blksz %x - err %d\n",217				mrq->data->blocks,218				mrq->data->blksz,219				mrq->data->error);220		}221		bcm2835_dumpcmd(host, mrq->stop, "stop");222	}223 224	dev_dbg(dev, "=========== REGISTER DUMP ===========\n");225	dev_dbg(dev, "SDCMD  0x%08x\n", readl(host->ioaddr + SDCMD));226	dev_dbg(dev, "SDARG  0x%08x\n", readl(host->ioaddr + SDARG));227	dev_dbg(dev, "SDTOUT 0x%08x\n", readl(host->ioaddr + SDTOUT));228	dev_dbg(dev, "SDCDIV 0x%08x\n", readl(host->ioaddr + SDCDIV));229	dev_dbg(dev, "SDRSP0 0x%08x\n", readl(host->ioaddr + SDRSP0));230	dev_dbg(dev, "SDRSP1 0x%08x\n", readl(host->ioaddr + SDRSP1));231	dev_dbg(dev, "SDRSP2 0x%08x\n", readl(host->ioaddr + SDRSP2));232	dev_dbg(dev, "SDRSP3 0x%08x\n", readl(host->ioaddr + SDRSP3));233	dev_dbg(dev, "SDHSTS 0x%08x\n", readl(host->ioaddr + SDHSTS));234	dev_dbg(dev, "SDVDD  0x%08x\n", readl(host->ioaddr + SDVDD));235	dev_dbg(dev, "SDEDM  0x%08x\n", readl(host->ioaddr + SDEDM));236	dev_dbg(dev, "SDHCFG 0x%08x\n", readl(host->ioaddr + SDHCFG));237	dev_dbg(dev, "SDHBCT 0x%08x\n", readl(host->ioaddr + SDHBCT));238	dev_dbg(dev, "SDHBLC 0x%08x\n", readl(host->ioaddr + SDHBLC));239	dev_dbg(dev, "===========================================\n");240}241 242static void bcm2835_reset_internal(struct bcm2835_host *host)243{244	u32 temp;245 246	writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);247	writel(0, host->ioaddr + SDCMD);248	writel(0, host->ioaddr + SDARG);249	writel(0xf00000, host->ioaddr + SDTOUT);250	writel(0, host->ioaddr + SDCDIV);251	writel(0x7f8, host->ioaddr + SDHSTS); /* Write 1s to clear */252	writel(0, host->ioaddr + SDHCFG);253	writel(0, host->ioaddr + SDHBCT);254	writel(0, host->ioaddr + SDHBLC);255 256	/* Limit fifo usage due to silicon bug */257	temp = readl(host->ioaddr + SDEDM);258	temp &= ~((SDEDM_THRESHOLD_MASK << SDEDM_READ_THRESHOLD_SHIFT) |259		  (SDEDM_THRESHOLD_MASK << SDEDM_WRITE_THRESHOLD_SHIFT));260	temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |261		(FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);262	writel(temp, host->ioaddr + SDEDM);263	msleep(20);264	writel(SDVDD_POWER_ON, host->ioaddr + SDVDD);265	msleep(20);266	host->clock = 0;267	writel(host->hcfg, host->ioaddr + SDHCFG);268	writel(host->cdiv, host->ioaddr + SDCDIV);269}270 271static void bcm2835_reset(struct mmc_host *mmc)272{273	struct bcm2835_host *host = mmc_priv(mmc);274 275	if (host->dma_chan)276		dmaengine_terminate_sync(host->dma_chan);277	host->dma_chan = NULL;278	bcm2835_reset_internal(host);279}280 281static void bcm2835_finish_command(struct bcm2835_host *host);282 283static void bcm2835_wait_transfer_complete(struct bcm2835_host *host)284{285	int timediff;286	u32 alternate_idle;287 288	alternate_idle = (host->mrq->data->flags & MMC_DATA_READ) ?289		SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1;290 291	timediff = 0;292 293	while (1) {294		u32 edm, fsm;295 296		edm = readl(host->ioaddr + SDEDM);297		fsm = edm & SDEDM_FSM_MASK;298 299		if ((fsm == SDEDM_FSM_IDENTMODE) ||300		    (fsm == SDEDM_FSM_DATAMODE))301			break;302		if (fsm == alternate_idle) {303			writel(edm | SDEDM_FORCE_DATA_MODE,304			       host->ioaddr + SDEDM);305			break;306		}307 308		timediff++;309		if (timediff == 100000) {310			dev_err(&host->pdev->dev,311				"wait_transfer_complete - still waiting after %d retries\n",312				timediff);313			bcm2835_dumpregs(host);314			host->mrq->data->error = -ETIMEDOUT;315			return;316		}317		cpu_relax();318	}319}320 321static void bcm2835_dma_complete(void *param)322{323	struct bcm2835_host *host = param;324 325	schedule_work(&host->dma_work);326}327 328static void bcm2835_transfer_block_pio(struct bcm2835_host *host, bool is_read)329{330	size_t blksize;331	unsigned long wait_max;332 333	blksize = host->data->blksz;334 335	wait_max = jiffies + msecs_to_jiffies(500);336 337	while (blksize) {338		int copy_words;339		u32 hsts = 0;340		size_t len;341		u32 *buf;342 343		if (!sg_miter_next(&host->sg_miter)) {344			host->data->error = -EINVAL;345			break;346		}347 348		len = min(host->sg_miter.length, blksize);349		if (len % 4) {350			host->data->error = -EINVAL;351			break;352		}353 354		blksize -= len;355		host->sg_miter.consumed = len;356 357		buf = (u32 *)host->sg_miter.addr;358 359		copy_words = len / 4;360 361		while (copy_words) {362			int burst_words, words;363			u32 edm;364 365			burst_words = min(SDDATA_FIFO_PIO_BURST, copy_words);366			edm = readl(host->ioaddr + SDEDM);367			if (is_read)368				words = ((edm >> 4) & 0x1f);369			else370				words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f);371 372			if (words < burst_words) {373				int fsm_state = (edm & SDEDM_FSM_MASK);374				struct device *dev = &host->pdev->dev;375 376				if ((is_read &&377				     (fsm_state != SDEDM_FSM_READDATA &&378				      fsm_state != SDEDM_FSM_READWAIT &&379				      fsm_state != SDEDM_FSM_READCRC)) ||380				    (!is_read &&381				     (fsm_state != SDEDM_FSM_WRITEDATA &&382				      fsm_state != SDEDM_FSM_WRITESTART1 &&383				      fsm_state != SDEDM_FSM_WRITESTART2))) {384					hsts = readl(host->ioaddr + SDHSTS);385					dev_err(dev, "fsm %x, hsts %08x\n",386						fsm_state, hsts);387					if (hsts & SDHSTS_ERROR_MASK)388						break;389				}390 391				if (time_after(jiffies, wait_max)) {392					dev_err(dev, "PIO %s timeout - EDM %08x\n",393						is_read ? "read" : "write",394						edm);395					hsts = SDHSTS_REW_TIME_OUT;396					break;397				}398				ndelay((burst_words - words) *399				       host->ns_per_fifo_word);400				continue;401			} else if (words > copy_words) {402				words = copy_words;403			}404 405			copy_words -= words;406 407			while (words) {408				if (is_read)409					*(buf++) = readl(host->ioaddr + SDDATA);410				else411					writel(*(buf++), host->ioaddr + SDDATA);412				words--;413			}414		}415 416		if (hsts & SDHSTS_ERROR_MASK)417			break;418	}419 420	sg_miter_stop(&host->sg_miter);421}422 423static void bcm2835_transfer_pio(struct bcm2835_host *host)424{425	struct device *dev = &host->pdev->dev;426	u32 sdhsts;427	bool is_read;428 429	is_read = (host->data->flags & MMC_DATA_READ) != 0;430	bcm2835_transfer_block_pio(host, is_read);431 432	sdhsts = readl(host->ioaddr + SDHSTS);433	if (sdhsts & (SDHSTS_CRC16_ERROR |434		      SDHSTS_CRC7_ERROR |435		      SDHSTS_FIFO_ERROR)) {436		dev_err(dev, "%s transfer error - HSTS %08x\n",437			is_read ? "read" : "write", sdhsts);438		host->data->error = -EILSEQ;439	} else if ((sdhsts & (SDHSTS_CMD_TIME_OUT |440			      SDHSTS_REW_TIME_OUT))) {441		dev_err(dev, "%s timeout error - HSTS %08x\n",442			is_read ? "read" : "write", sdhsts);443		host->data->error = -ETIMEDOUT;444	}445}446 447static448void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data)449{450	int sg_len, dir_data, dir_slave;451	struct dma_async_tx_descriptor *desc = NULL;452	struct dma_chan *dma_chan;453 454	dma_chan = host->dma_chan_rxtx;455	if (data->flags & MMC_DATA_READ) {456		dir_data = DMA_FROM_DEVICE;457		dir_slave = DMA_DEV_TO_MEM;458	} else {459		dir_data = DMA_TO_DEVICE;460		dir_slave = DMA_MEM_TO_DEV;461	}462 463	/* The block doesn't manage the FIFO DREQs properly for464	 * multi-block transfers, so don't attempt to DMA the final465	 * few words.  Unfortunately this requires the final sg entry466	 * to be trimmed.  N.B. This code demands that the overspill467	 * is contained in a single sg entry.468	 */469 470	host->drain_words = 0;471	if ((data->blocks > 1) && (dir_data == DMA_FROM_DEVICE)) {472		struct scatterlist *sg;473		u32 len;474		int i;475 476		len = min((u32)(FIFO_READ_THRESHOLD - 1) * 4,477			  (u32)data->blocks * data->blksz);478 479		for_each_sg(data->sg, sg, data->sg_len, i) {480			if (sg_is_last(sg)) {481				WARN_ON(sg->length < len);482				sg->length -= len;483				host->drain_page = sg_page(sg);484				host->drain_offset = sg->offset + sg->length;485			}486		}487		host->drain_words = len / 4;488	}489 490	/* The parameters have already been validated, so this will not fail */491	(void)dmaengine_slave_config(dma_chan,492				     (dir_data == DMA_FROM_DEVICE) ?493				     &host->dma_cfg_rx :494				     &host->dma_cfg_tx);495 496	sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len,497			    dir_data);498	if (!sg_len)499		return;500 501	desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave,502				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);503 504	if (!desc) {505		dma_unmap_sg(dma_chan->device->dev, data->sg, sg_len, dir_data);506		return;507	}508 509	desc->callback = bcm2835_dma_complete;510	desc->callback_param = host;511	host->dma_desc = desc;512	host->dma_chan = dma_chan;513	host->dma_dir = dir_data;514}515 516static void bcm2835_start_dma(struct bcm2835_host *host)517{518	dmaengine_submit(host->dma_desc);519	dma_async_issue_pending(host->dma_chan);520}521 522static void bcm2835_set_transfer_irqs(struct bcm2835_host *host)523{524	u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN |525		SDHCFG_BUSY_IRPT_EN;526 527	if (host->dma_desc) {528		host->hcfg = (host->hcfg & ~all_irqs) |529			SDHCFG_BUSY_IRPT_EN;530	} else {531		host->hcfg = (host->hcfg & ~all_irqs) |532			SDHCFG_DATA_IRPT_EN |533			SDHCFG_BUSY_IRPT_EN;534	}535 536	writel(host->hcfg, host->ioaddr + SDHCFG);537}538 539static540void bcm2835_prepare_data(struct bcm2835_host *host, struct mmc_command *cmd)541{542	struct mmc_data *data = cmd->data;543 544	WARN_ON(host->data);545 546	host->data = data;547	if (!data)548		return;549 550	host->data_complete = false;551	host->data->bytes_xfered = 0;552 553	if (!host->dma_desc) {554		/* Use PIO */555		int flags = SG_MITER_ATOMIC;556 557		if (data->flags & MMC_DATA_READ)558			flags |= SG_MITER_TO_SG;559		else560			flags |= SG_MITER_FROM_SG;561		sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);562		host->blocks = data->blocks;563	}564 565	bcm2835_set_transfer_irqs(host);566 567	writel(data->blksz, host->ioaddr + SDHBCT);568	writel(data->blocks, host->ioaddr + SDHBLC);569}570 571static u32 bcm2835_read_wait_sdcmd(struct bcm2835_host *host, u32 max_ms)572{573	struct device *dev = &host->pdev->dev;574	u32 value;575	int ret;576 577	ret = readl_poll_timeout(host->ioaddr + SDCMD, value,578				 !(value & SDCMD_NEW_FLAG), 1, 10);579	if (ret == -ETIMEDOUT)580		/* if it takes a while make poll interval bigger */581		ret = readl_poll_timeout(host->ioaddr + SDCMD, value,582					 !(value & SDCMD_NEW_FLAG),583					 10, max_ms * 1000);584	if (ret == -ETIMEDOUT)585		dev_err(dev, "%s: timeout (%d ms)\n", __func__, max_ms);586 587	return value;588}589 590static void bcm2835_finish_request(struct bcm2835_host *host)591{592	struct dma_chan *terminate_chan = NULL;593	struct mmc_request *mrq;594 595	cancel_delayed_work(&host->timeout_work);596 597	mrq = host->mrq;598 599	host->mrq = NULL;600	host->cmd = NULL;601	host->data = NULL;602 603	host->dma_desc = NULL;604	terminate_chan = host->dma_chan;605	host->dma_chan = NULL;606 607	if (terminate_chan) {608		int err = dmaengine_terminate_all(terminate_chan);609 610		if (err)611			dev_err(&host->pdev->dev,612				"failed to terminate DMA (%d)\n", err);613	}614 615	mmc_request_done(mmc_from_priv(host), mrq);616}617 618static619bool bcm2835_send_command(struct bcm2835_host *host, struct mmc_command *cmd)620{621	struct device *dev = &host->pdev->dev;622	u32 sdcmd, sdhsts;623	unsigned long timeout;624 625	WARN_ON(host->cmd);626 627	sdcmd = bcm2835_read_wait_sdcmd(host, 100);628	if (sdcmd & SDCMD_NEW_FLAG) {629		dev_err(dev, "previous command never completed.\n");630		bcm2835_dumpregs(host);631		cmd->error = -EILSEQ;632		bcm2835_finish_request(host);633		return false;634	}635 636	if (!cmd->data && cmd->busy_timeout > 9000)637		timeout = DIV_ROUND_UP(cmd->busy_timeout, 1000) * HZ + HZ;638	else639		timeout = 10 * HZ;640	schedule_delayed_work(&host->timeout_work, timeout);641 642	host->cmd = cmd;643 644	/* Clear any error flags */645	sdhsts = readl(host->ioaddr + SDHSTS);646	if (sdhsts & SDHSTS_ERROR_MASK)647		writel(sdhsts, host->ioaddr + SDHSTS);648 649	if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {650		dev_err(dev, "unsupported response type!\n");651		cmd->error = -EINVAL;652		bcm2835_finish_request(host);653		return false;654	}655 656	bcm2835_prepare_data(host, cmd);657 658	writel(cmd->arg, host->ioaddr + SDARG);659 660	sdcmd = cmd->opcode & SDCMD_CMD_MASK;661 662	host->use_busy = false;663	if (!(cmd->flags & MMC_RSP_PRESENT)) {664		sdcmd |= SDCMD_NO_RESPONSE;665	} else {666		if (cmd->flags & MMC_RSP_136)667			sdcmd |= SDCMD_LONG_RESPONSE;668		if (cmd->flags & MMC_RSP_BUSY) {669			sdcmd |= SDCMD_BUSYWAIT;670			host->use_busy = true;671		}672	}673 674	if (cmd->data) {675		if (cmd->data->flags & MMC_DATA_WRITE)676			sdcmd |= SDCMD_WRITE_CMD;677		if (cmd->data->flags & MMC_DATA_READ)678			sdcmd |= SDCMD_READ_CMD;679	}680 681	writel(sdcmd | SDCMD_NEW_FLAG, host->ioaddr + SDCMD);682 683	return true;684}685 686static void bcm2835_transfer_complete(struct bcm2835_host *host)687{688	struct mmc_data *data;689 690	WARN_ON(!host->data_complete);691 692	data = host->data;693	host->data = NULL;694 695	/* Need to send CMD12 if -696	 * a) open-ended multiblock transfer (no CMD23)697	 * b) error in multiblock transfer698	 */699	if (host->mrq->stop && (data->error || !host->use_sbc)) {700		if (bcm2835_send_command(host, host->mrq->stop)) {701			/* No busy, so poll for completion */702			if (!host->use_busy)703				bcm2835_finish_command(host);704		}705	} else {706		bcm2835_wait_transfer_complete(host);707		bcm2835_finish_request(host);708	}709}710 711static void bcm2835_finish_data(struct bcm2835_host *host)712{713	struct device *dev = &host->pdev->dev;714	struct mmc_data *data;715 716	data = host->data;717 718	host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);719	writel(host->hcfg, host->ioaddr + SDHCFG);720 721	data->bytes_xfered = data->error ? 0 : (data->blksz * data->blocks);722 723	host->data_complete = true;724 725	if (host->cmd) {726		/* Data managed to finish before the727		 * command completed. Make sure we do728		 * things in the proper order.729		 */730		dev_dbg(dev, "Finished early - HSTS %08x\n",731			readl(host->ioaddr + SDHSTS));732	} else {733		bcm2835_transfer_complete(host);734	}735}736 737static void bcm2835_finish_command(struct bcm2835_host *host)738{739	struct device *dev = &host->pdev->dev;740	struct mmc_command *cmd = host->cmd;741	u32 sdcmd;742 743	sdcmd = bcm2835_read_wait_sdcmd(host, 100);744 745	/* Check for errors */746	if (sdcmd & SDCMD_NEW_FLAG) {747		dev_err(dev, "command never completed.\n");748		bcm2835_dumpregs(host);749		host->cmd->error = -EIO;750		bcm2835_finish_request(host);751		return;752	} else if (sdcmd & SDCMD_FAIL_FLAG) {753		u32 sdhsts = readl(host->ioaddr + SDHSTS);754 755		/* Clear the errors */756		writel(SDHSTS_ERROR_MASK, host->ioaddr + SDHSTS);757 758		if (!(sdhsts & SDHSTS_CRC7_ERROR) ||759		    (host->cmd->opcode != MMC_SEND_OP_COND)) {760			u32 edm, fsm;761 762			if (sdhsts & SDHSTS_CMD_TIME_OUT) {763				host->cmd->error = -ETIMEDOUT;764			} else {765				dev_err(dev, "unexpected command %d error\n",766					host->cmd->opcode);767				bcm2835_dumpregs(host);768				host->cmd->error = -EILSEQ;769			}770			edm = readl(host->ioaddr + SDEDM);771			fsm = edm & SDEDM_FSM_MASK;772			if (fsm == SDEDM_FSM_READWAIT ||773			    fsm == SDEDM_FSM_WRITESTART1)774				/* Kick the FSM out of its wait */775				writel(edm | SDEDM_FORCE_DATA_MODE,776				       host->ioaddr + SDEDM);777			bcm2835_finish_request(host);778			return;779		}780	}781 782	if (cmd->flags & MMC_RSP_PRESENT) {783		if (cmd->flags & MMC_RSP_136) {784			int i;785 786			for (i = 0; i < 4; i++) {787				cmd->resp[3 - i] =788					readl(host->ioaddr + SDRSP0 + i * 4);789			}790		} else {791			cmd->resp[0] = readl(host->ioaddr + SDRSP0);792		}793	}794 795	if (cmd == host->mrq->sbc) {796		/* Finished CMD23, now send actual command. */797		host->cmd = NULL;798		if (bcm2835_send_command(host, host->mrq->cmd)) {799			if (host->data && host->dma_desc)800				/* DMA transfer starts now, PIO starts801				 * after irq802				 */803				bcm2835_start_dma(host);804 805			if (!host->use_busy)806				bcm2835_finish_command(host);807		}808	} else if (cmd == host->mrq->stop) {809		/* Finished CMD12 */810		bcm2835_finish_request(host);811	} else {812		/* Processed actual command. */813		host->cmd = NULL;814		if (!host->data)815			bcm2835_finish_request(host);816		else if (host->data_complete)817			bcm2835_transfer_complete(host);818	}819}820 821static void bcm2835_timeout(struct work_struct *work)822{823	struct delayed_work *d = to_delayed_work(work);824	struct bcm2835_host *host =825		container_of(d, struct bcm2835_host, timeout_work);826	struct device *dev = &host->pdev->dev;827 828	mutex_lock(&host->mutex);829 830	if (host->mrq) {831		dev_err(dev, "timeout waiting for hardware interrupt.\n");832		bcm2835_dumpregs(host);833 834		bcm2835_reset(mmc_from_priv(host));835 836		if (host->data) {837			host->data->error = -ETIMEDOUT;838			bcm2835_finish_data(host);839		} else {840			if (host->cmd)841				host->cmd->error = -ETIMEDOUT;842			else843				host->mrq->cmd->error = -ETIMEDOUT;844 845			bcm2835_finish_request(host);846		}847	}848 849	mutex_unlock(&host->mutex);850}851 852static bool bcm2835_check_cmd_error(struct bcm2835_host *host, u32 intmask)853{854	struct device *dev = &host->pdev->dev;855 856	if (!(intmask & SDHSTS_ERROR_MASK))857		return false;858 859	if (!host->cmd)860		return true;861 862	dev_err(dev, "sdhost_busy_irq: intmask %08x\n", intmask);863	if (intmask & SDHSTS_CRC7_ERROR) {864		host->cmd->error = -EILSEQ;865	} else if (intmask & (SDHSTS_CRC16_ERROR |866			      SDHSTS_FIFO_ERROR)) {867		if (host->mrq->data)868			host->mrq->data->error = -EILSEQ;869		else870			host->cmd->error = -EILSEQ;871	} else if (intmask & SDHSTS_REW_TIME_OUT) {872		if (host->mrq->data)873			host->mrq->data->error = -ETIMEDOUT;874		else875			host->cmd->error = -ETIMEDOUT;876	} else if (intmask & SDHSTS_CMD_TIME_OUT) {877		host->cmd->error = -ETIMEDOUT;878	}879	bcm2835_dumpregs(host);880	return true;881}882 883static void bcm2835_check_data_error(struct bcm2835_host *host, u32 intmask)884{885	if (!host->data)886		return;887	if (intmask & (SDHSTS_CRC16_ERROR | SDHSTS_FIFO_ERROR))888		host->data->error = -EILSEQ;889	if (intmask & SDHSTS_REW_TIME_OUT)890		host->data->error = -ETIMEDOUT;891}892 893static void bcm2835_busy_irq(struct bcm2835_host *host)894{895	if (WARN_ON(!host->cmd)) {896		bcm2835_dumpregs(host);897		return;898	}899 900	if (WARN_ON(!host->use_busy)) {901		bcm2835_dumpregs(host);902		return;903	}904	host->use_busy = false;905 906	bcm2835_finish_command(host);907}908 909static void bcm2835_data_irq(struct bcm2835_host *host, u32 intmask)910{911	/* There are no dedicated data/space available interrupt912	 * status bits, so it is necessary to use the single shared913	 * data/space available FIFO status bits. It is therefore not914	 * an error to get here when there is no data transfer in915	 * progress.916	 */917	if (!host->data)918		return;919 920	bcm2835_check_data_error(host, intmask);921	if (host->data->error)922		goto finished;923 924	if (host->data->flags & MMC_DATA_WRITE) {925		/* Use the block interrupt for writes after the first block */926		host->hcfg &= ~(SDHCFG_DATA_IRPT_EN);927		host->hcfg |= SDHCFG_BLOCK_IRPT_EN;928		writel(host->hcfg, host->ioaddr + SDHCFG);929		bcm2835_transfer_pio(host);930	} else {931		bcm2835_transfer_pio(host);932		host->blocks--;933		if ((host->blocks == 0) || host->data->error)934			goto finished;935	}936	return;937 938finished:939	host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);940	writel(host->hcfg, host->ioaddr + SDHCFG);941}942 943static void bcm2835_data_threaded_irq(struct bcm2835_host *host)944{945	if (!host->data)946		return;947	if ((host->blocks == 0) || host->data->error)948		bcm2835_finish_data(host);949}950 951static void bcm2835_block_irq(struct bcm2835_host *host)952{953	if (WARN_ON(!host->data)) {954		bcm2835_dumpregs(host);955		return;956	}957 958	if (!host->dma_desc) {959		WARN_ON(!host->blocks);960		if (host->data->error || (--host->blocks == 0))961			bcm2835_finish_data(host);962		else963			bcm2835_transfer_pio(host);964	} else if (host->data->flags & MMC_DATA_WRITE) {965		bcm2835_finish_data(host);966	}967}968 969static irqreturn_t bcm2835_irq(int irq, void *dev_id)970{971	irqreturn_t result = IRQ_NONE;972	struct bcm2835_host *host = dev_id;973	u32 intmask;974 975	spin_lock(&host->lock);976 977	intmask = readl(host->ioaddr + SDHSTS);978 979	writel(SDHSTS_BUSY_IRPT |980	       SDHSTS_BLOCK_IRPT |981	       SDHSTS_SDIO_IRPT |982	       SDHSTS_DATA_FLAG,983	       host->ioaddr + SDHSTS);984 985	if (intmask & SDHSTS_BLOCK_IRPT) {986		bcm2835_check_data_error(host, intmask);987		host->irq_block = true;988		result = IRQ_WAKE_THREAD;989	}990 991	if (intmask & SDHSTS_BUSY_IRPT) {992		if (!bcm2835_check_cmd_error(host, intmask)) {993			host->irq_busy = true;994			result = IRQ_WAKE_THREAD;995		} else {996			result = IRQ_HANDLED;997		}998	}999 1000	/* There is no true data interrupt status bit, so it is1001	 * necessary to qualify the data flag with the interrupt1002	 * enable bit.1003	 */1004	if ((intmask & SDHSTS_DATA_FLAG) &&1005	    (host->hcfg & SDHCFG_DATA_IRPT_EN)) {1006		bcm2835_data_irq(host, intmask);1007		host->irq_data = true;1008		result = IRQ_WAKE_THREAD;1009	}1010 1011	spin_unlock(&host->lock);1012 1013	return result;1014}1015 1016static irqreturn_t bcm2835_threaded_irq(int irq, void *dev_id)1017{1018	struct bcm2835_host *host = dev_id;1019	unsigned long flags;1020	bool block, busy, data;1021 1022	spin_lock_irqsave(&host->lock, flags);1023 1024	block = host->irq_block;1025	busy  = host->irq_busy;1026	data  = host->irq_data;1027	host->irq_block = false;1028	host->irq_busy  = false;1029	host->irq_data  = false;1030 1031	spin_unlock_irqrestore(&host->lock, flags);1032 1033	mutex_lock(&host->mutex);1034 1035	if (block)1036		bcm2835_block_irq(host);1037	if (busy)1038		bcm2835_busy_irq(host);1039	if (data)1040		bcm2835_data_threaded_irq(host);1041 1042	mutex_unlock(&host->mutex);1043 1044	return IRQ_HANDLED;1045}1046 1047static void bcm2835_dma_complete_work(struct work_struct *work)1048{1049	struct bcm2835_host *host =1050		container_of(work, struct bcm2835_host, dma_work);1051	struct mmc_data *data;1052 1053	mutex_lock(&host->mutex);1054 1055	data = host->data;1056 1057	if (host->dma_chan) {1058		dma_unmap_sg(host->dma_chan->device->dev,1059			     data->sg, data->sg_len,1060			     host->dma_dir);1061 1062		host->dma_chan = NULL;1063	}1064 1065	if (host->drain_words) {1066		void *page;1067		u32 *buf;1068 1069		if (host->drain_offset & PAGE_MASK) {1070			host->drain_page += host->drain_offset >> PAGE_SHIFT;1071			host->drain_offset &= ~PAGE_MASK;1072		}1073		page = kmap_local_page(host->drain_page);1074		buf = page + host->drain_offset;1075 1076		while (host->drain_words) {1077			u32 edm = readl(host->ioaddr + SDEDM);1078 1079			if ((edm >> 4) & 0x1f)1080				*(buf++) = readl(host->ioaddr + SDDATA);1081			host->drain_words--;1082		}1083 1084		kunmap_local(page);1085	}1086 1087	bcm2835_finish_data(host);1088 1089	mutex_unlock(&host->mutex);1090}1091 1092static void bcm2835_set_clock(struct bcm2835_host *host, unsigned int clock)1093{1094	struct mmc_host *mmc = mmc_from_priv(host);1095	int div;1096 1097	/* The SDCDIV register has 11 bits, and holds (div - 2).  But1098	 * in data mode the max is 50MHz wihout a minimum, and only1099	 * the bottom 3 bits are used. Since the switch over is1100	 * automatic (unless we have marked the card as slow...),1101	 * chosen values have to make sense in both modes.  Ident mode1102	 * must be 100-400KHz, so can range check the requested1103	 * clock. CMD15 must be used to return to data mode, so this1104	 * can be monitored.1105	 *1106	 * clock 250MHz -> 0->125MHz, 1->83.3MHz, 2->62.5MHz, 3->50.0MHz1107	 *                 4->41.7MHz, 5->35.7MHz, 6->31.3MHz, 7->27.8MHz1108	 *1109	 *		 623->400KHz/27.8MHz1110	 *		 reset value (507)->491159/50MHz1111	 *1112	 * BUT, the 3-bit clock divisor in data mode is too small if1113	 * the core clock is higher than 250MHz, so instead use the1114	 * SLOW_CARD configuration bit to force the use of the ident1115	 * clock divisor at all times.1116	 */1117 1118	if (clock < 100000) {1119		/* Can't stop the clock, but make it as slow as possible1120		 * to show willing1121		 */1122		host->cdiv = SDCDIV_MAX_CDIV;1123		writel(host->cdiv, host->ioaddr + SDCDIV);1124		return;1125	}1126 1127	div = host->max_clk / clock;1128	if (div < 2)1129		div = 2;1130	if ((host->max_clk / div) > clock)1131		div++;1132	div -= 2;1133 1134	if (div > SDCDIV_MAX_CDIV)1135		div = SDCDIV_MAX_CDIV;1136 1137	clock = host->max_clk / (div + 2);1138	mmc->actual_clock = clock;1139 1140	/* Calibrate some delays */1141 1142	host->ns_per_fifo_word = (1000000000 / clock) *1143		((mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32);1144 1145	host->cdiv = div;1146	writel(host->cdiv, host->ioaddr + SDCDIV);1147 1148	/* Set the timeout to 500ms */1149	writel(mmc->actual_clock / 2, host->ioaddr + SDTOUT);1150}1151 1152static void bcm2835_request(struct mmc_host *mmc, struct mmc_request *mrq)1153{1154	struct bcm2835_host *host = mmc_priv(mmc);1155	struct device *dev = &host->pdev->dev;1156	u32 edm, fsm;1157 1158	/* Reset the error statuses in case this is a retry */1159	if (mrq->sbc)1160		mrq->sbc->error = 0;1161	if (mrq->cmd)1162		mrq->cmd->error = 0;1163	if (mrq->data)1164		mrq->data->error = 0;1165	if (mrq->stop)1166		mrq->stop->error = 0;1167 1168	if (mrq->data && !is_power_of_2(mrq->data->blksz)) {1169		dev_err(dev, "unsupported block size (%d bytes)\n",1170			mrq->data->blksz);1171 1172		if (mrq->cmd)1173			mrq->cmd->error = -EINVAL;1174 1175		mmc_request_done(mmc, mrq);1176		return;1177	}1178 1179	mutex_lock(&host->mutex);1180 1181	WARN_ON(host->mrq);1182	host->mrq = mrq;1183 1184	edm = readl(host->ioaddr + SDEDM);1185	fsm = edm & SDEDM_FSM_MASK;1186 1187	if ((fsm != SDEDM_FSM_IDENTMODE) &&1188	    (fsm != SDEDM_FSM_DATAMODE)) {1189		dev_err(dev, "previous command (%d) not complete (EDM %08x)\n",1190			readl(host->ioaddr + SDCMD) & SDCMD_CMD_MASK,1191			edm);1192		bcm2835_dumpregs(host);1193 1194		if (mrq->cmd)1195			mrq->cmd->error = -EILSEQ;1196 1197		bcm2835_finish_request(host);1198		mutex_unlock(&host->mutex);1199		return;1200	}1201 1202	if (host->use_dma && mrq->data && (mrq->data->blocks > PIO_THRESHOLD))1203		bcm2835_prepare_dma(host, mrq->data);1204 1205	host->use_sbc = !!mrq->sbc && host->mrq->data &&1206			(host->mrq->data->flags & MMC_DATA_READ);1207	if (host->use_sbc) {1208		if (bcm2835_send_command(host, mrq->sbc)) {1209			if (!host->use_busy)1210				bcm2835_finish_command(host);1211		}1212	} else if (mrq->cmd && bcm2835_send_command(host, mrq->cmd)) {1213		if (host->data && host->dma_desc) {1214			/* DMA transfer starts now, PIO starts after irq */1215			bcm2835_start_dma(host);1216		}1217 1218		if (!host->use_busy)1219			bcm2835_finish_command(host);1220	}1221 1222	mutex_unlock(&host->mutex);1223}1224 1225static void bcm2835_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)1226{1227	struct bcm2835_host *host = mmc_priv(mmc);1228 1229	mutex_lock(&host->mutex);1230 1231	if (!ios->clock || ios->clock != host->clock) {1232		bcm2835_set_clock(host, ios->clock);1233		host->clock = ios->clock;1234	}1235 1236	/* set bus width */1237	host->hcfg &= ~SDHCFG_WIDE_EXT_BUS;1238	if (ios->bus_width == MMC_BUS_WIDTH_4)1239		host->hcfg |= SDHCFG_WIDE_EXT_BUS;1240 1241	host->hcfg |= SDHCFG_WIDE_INT_BUS;1242 1243	/* Disable clever clock switching, to cope with fast core clocks */1244	host->hcfg |= SDHCFG_SLOW_CARD;1245 1246	writel(host->hcfg, host->ioaddr + SDHCFG);1247 1248	mutex_unlock(&host->mutex);1249}1250 1251static const struct mmc_host_ops bcm2835_ops = {1252	.request = bcm2835_request,1253	.set_ios = bcm2835_set_ios,1254	.card_hw_reset = bcm2835_reset,1255};1256 1257static int bcm2835_add_host(struct bcm2835_host *host)1258{1259	struct mmc_host *mmc = mmc_from_priv(host);1260	struct device *dev = &host->pdev->dev;1261	char pio_limit_string[20];1262	int ret;1263 1264	if (!mmc->f_max || mmc->f_max > host->max_clk)1265		mmc->f_max = host->max_clk;1266	mmc->f_min = host->max_clk / SDCDIV_MAX_CDIV;1267 1268	mmc->max_busy_timeout = ~0 / (mmc->f_max / 1000);1269 1270	dev_dbg(dev, "f_max %d, f_min %d, max_busy_timeout %d\n",1271		mmc->f_max, mmc->f_min, mmc->max_busy_timeout);1272 1273	/* host controller capabilities */1274	mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |1275		     MMC_CAP_NEEDS_POLL | MMC_CAP_HW_RESET | MMC_CAP_CMD23;1276 1277	spin_lock_init(&host->lock);1278	mutex_init(&host->mutex);1279 1280	if (!host->dma_chan_rxtx) {1281		dev_warn(dev, "unable to initialise DMA channel. Falling back to PIO\n");1282		host->use_dma = false;1283	} else {1284		host->use_dma = true;1285 1286		host->dma_cfg_tx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;1287		host->dma_cfg_tx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;1288		host->dma_cfg_tx.direction = DMA_MEM_TO_DEV;1289		host->dma_cfg_tx.src_addr = 0;1290		host->dma_cfg_tx.dst_addr = host->phys_addr + SDDATA;1291 1292		host->dma_cfg_rx.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;1293		host->dma_cfg_rx.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;1294		host->dma_cfg_rx.direction = DMA_DEV_TO_MEM;1295		host->dma_cfg_rx.src_addr = host->phys_addr + SDDATA;1296		host->dma_cfg_rx.dst_addr = 0;1297 1298		if (dmaengine_slave_config(host->dma_chan_rxtx,1299					   &host->dma_cfg_tx) != 0 ||1300		    dmaengine_slave_config(host->dma_chan_rxtx,1301					   &host->dma_cfg_rx) != 0)1302			host->use_dma = false;1303	}1304 1305	mmc->max_segs = 128;1306	mmc->max_req_size = min_t(size_t, 524288, dma_max_mapping_size(dev));1307	mmc->max_seg_size = mmc->max_req_size;1308	mmc->max_blk_size = 1024;1309	mmc->max_blk_count =  65535;1310 1311	/* report supported voltage ranges */1312	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;1313 1314	INIT_WORK(&host->dma_work, bcm2835_dma_complete_work);1315	INIT_DELAYED_WORK(&host->timeout_work, bcm2835_timeout);1316 1317	/* Set interrupt enables */1318	host->hcfg = SDHCFG_BUSY_IRPT_EN;1319 1320	bcm2835_reset_internal(host);1321 1322	ret = request_threaded_irq(host->irq, bcm2835_irq,1323				   bcm2835_threaded_irq,1324				   0, mmc_hostname(mmc), host);1325	if (ret) {1326		dev_err(dev, "failed to request IRQ %d: %d\n", host->irq, ret);1327		return ret;1328	}1329 1330	ret = mmc_add_host(mmc);1331	if (ret) {1332		free_irq(host->irq, host);1333		return ret;1334	}1335 1336	pio_limit_string[0] = '\0';1337	if (host->use_dma && (PIO_THRESHOLD > 0))1338		sprintf(pio_limit_string, " (>%d)", PIO_THRESHOLD);1339	dev_info(dev, "loaded - DMA %s%s\n",1340		 host->use_dma ? "enabled" : "disabled", pio_limit_string);1341 1342	return 0;1343}1344 1345static int bcm2835_probe(struct platform_device *pdev)1346{1347	struct device *dev = &pdev->dev;1348	struct clk *clk;1349	struct bcm2835_host *host;1350	struct mmc_host *mmc;1351	const __be32 *regaddr_p;1352	int ret;1353 1354	dev_dbg(dev, "%s\n", __func__);1355	mmc = mmc_alloc_host(sizeof(*host), dev);1356	if (!mmc)1357		return -ENOMEM;1358 1359	mmc->ops = &bcm2835_ops;1360	host = mmc_priv(mmc);1361	host->pdev = pdev;1362	spin_lock_init(&host->lock);1363 1364	host->ioaddr = devm_platform_ioremap_resource(pdev, 0);1365	if (IS_ERR(host->ioaddr)) {1366		ret = PTR_ERR(host->ioaddr);1367		goto err;1368	}1369 1370	/* Parse OF address directly to get the physical address for1371	 * DMA to our registers.1372	 */1373	regaddr_p = of_get_address(pdev->dev.of_node, 0, NULL, NULL);1374	if (!regaddr_p) {1375		dev_err(dev, "Can't get phys address\n");1376		ret = -EINVAL;1377		goto err;1378	}1379 1380	host->phys_addr = be32_to_cpup(regaddr_p);1381 1382	host->dma_chan = NULL;1383	host->dma_desc = NULL;1384 1385	host->dma_chan_rxtx = dma_request_chan(dev, "rx-tx");1386	if (IS_ERR(host->dma_chan_rxtx)) {1387		ret = PTR_ERR(host->dma_chan_rxtx);1388		host->dma_chan_rxtx = NULL;1389 1390		if (ret == -EPROBE_DEFER)1391			goto err;1392 1393		/* Ignore errors to fall back to PIO mode */1394	}1395 1396 1397	clk = devm_clk_get(dev, NULL);1398	if (IS_ERR(clk)) {1399		ret = dev_err_probe(dev, PTR_ERR(clk), "could not get clk\n");1400		goto err;1401	}1402 1403	host->max_clk = clk_get_rate(clk);1404 1405	host->irq = platform_get_irq(pdev, 0);1406	if (host->irq < 0) {1407		ret = host->irq;1408		goto err;1409	}1410 1411	ret = mmc_of_parse(mmc);1412	if (ret)1413		goto err;1414 1415	ret = bcm2835_add_host(host);1416	if (ret)1417		goto err;1418 1419	platform_set_drvdata(pdev, host);1420 1421	dev_dbg(dev, "%s -> OK\n", __func__);1422 1423	return 0;1424 1425err:1426	dev_dbg(dev, "%s -> err %d\n", __func__, ret);1427	if (host->dma_chan_rxtx)1428		dma_release_channel(host->dma_chan_rxtx);1429	mmc_free_host(mmc);1430 1431	return ret;1432}1433 1434static void bcm2835_remove(struct platform_device *pdev)1435{1436	struct bcm2835_host *host = platform_get_drvdata(pdev);1437	struct mmc_host *mmc = mmc_from_priv(host);1438 1439	mmc_remove_host(mmc);1440 1441	writel(SDVDD_POWER_OFF, host->ioaddr + SDVDD);1442 1443	free_irq(host->irq, host);1444 1445	cancel_work_sync(&host->dma_work);1446	cancel_delayed_work_sync(&host->timeout_work);1447 1448	if (host->dma_chan_rxtx)1449		dma_release_channel(host->dma_chan_rxtx);1450 1451	mmc_free_host(mmc);1452}1453 1454static const struct of_device_id bcm2835_match[] = {1455	{ .compatible = "brcm,bcm2835-sdhost" },1456	{ }1457};1458MODULE_DEVICE_TABLE(of, bcm2835_match);1459 1460static struct platform_driver bcm2835_driver = {1461	.probe      = bcm2835_probe,1462	.remove_new = bcm2835_remove,1463	.driver     = {1464		.name		= "sdhost-bcm2835",1465		.probe_type	= PROBE_PREFER_ASYNCHRONOUS,1466		.of_match_table	= bcm2835_match,1467	},1468};1469module_platform_driver(bcm2835_driver);1470 1471MODULE_ALIAS("platform:sdhost-bcm2835");1472MODULE_DESCRIPTION("BCM2835 SDHost driver");1473MODULE_LICENSE("GPL v2");1474MODULE_AUTHOR("Phil Elwell");1475