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Commit a406f5a3 authored by Pierre Ossman's avatar Pierre Ossman Committed by Russell King
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[MMC] Fix sdhci PIO routines 



The sdhci controllers operate with blocks, not bytes. The PIO routines must
therefore make sure that the minimum unit transfered is a complete block.

Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 3192a28f

drivers/mmc/sdhci.c

+98 −60
Original line number Diff line number Diff line
@@ -8,12 +8,6 @@ 
 * published by the Free Software Foundation.

 */



 /*

  * Note that PIO transfer is rather crappy atm. The buffer full/empty

  * interrupts aren't reliable so we currently transfer the entire buffer

  * directly. Patches to solve the problem are welcome.

  */



#include <linux/delay.h>

#include <linux/highmem.h>

#include <linux/pci.h>
@@ -128,7 +122,7 @@ static void sdhci_init(struct sdhci_host *host) 
		SDHCI_INT_DATA_CRC | SDHCI_INT_DATA_TIMEOUT | SDHCI_INT_INDEX |

		SDHCI_INT_END_BIT | SDHCI_INT_CRC | SDHCI_INT_TIMEOUT |

		SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT |

		SDHCI_INT_BUF_EMPTY | SDHCI_INT_BUF_FULL |

		SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL |

		SDHCI_INT_DMA_END | SDHCI_INT_DATA_END | SDHCI_INT_RESPONSE;



	writel(intmask, host->ioaddr + SDHCI_INT_ENABLE);
@@ -189,79 +183,96 @@ static inline int sdhci_next_sg(struct sdhci_host* host) 
	return host->num_sg;

}



static void sdhci_transfer_pio(struct sdhci_host *host)

static void sdhci_read_block_pio(struct sdhci_host *host)

{

	int blksize, chunk_remain;

	u32 data;

	char *buffer;

	u32 mask;

	int bytes, size;

	unsigned long max_jiffies;

	int size;



	BUG_ON(!host->data);

	DBG("PIO reading\n");



	if (host->num_sg == 0)

		return;



	bytes = 0;

	if (host->data->flags & MMC_DATA_READ)

		mask = SDHCI_DATA_AVAILABLE;

	else

		mask = SDHCI_SPACE_AVAILABLE;

	blksize = host->data->blksz;

	chunk_remain = 0;

	data = 0;



	buffer = sdhci_kmap_sg(host) + host->offset;



	/* Transfer shouldn't take more than 5 s */

	max_jiffies = jiffies + HZ * 5;

	while (blksize) {

		if (chunk_remain == 0) {

			data = readl(host->ioaddr + SDHCI_BUFFER);

			chunk_remain = min(blksize, 4);

		}



	while (host->size > 0) {

		if (time_after(jiffies, max_jiffies)) {

			printk(KERN_ERR "%s: PIO transfer stalled. "

				"Please report this to "

				BUGMAIL ".\n", mmc_hostname(host->mmc));

			sdhci_dumpregs(host);

		size = min(host->size, host->remain);

		size = min(size, chunk_remain);



			sdhci_kunmap_sg(host);

		chunk_remain -= size;

		blksize -= size;

		host->offset += size;

		host->remain -= size;

		host->size -= size;

		while (size) {

			*buffer = data & 0xFF;

			buffer++;

			data >>= 8;

			size--;

		}



			host->data->error = MMC_ERR_FAILED;

			sdhci_finish_data(host);

		if (host->remain == 0) {

			sdhci_kunmap_sg(host);

			if (sdhci_next_sg(host) == 0) {

				BUG_ON(blksize != 0);

				return;

			}

			buffer = sdhci_kmap_sg(host);

		}

	}



		if (!(readl(host->ioaddr + SDHCI_PRESENT_STATE) & mask))

			continue;

	sdhci_kunmap_sg(host);

}



		size = min(host->size, host->remain);

static void sdhci_write_block_pio(struct sdhci_host *host)

{

	int blksize, chunk_remain;

	u32 data;

	char *buffer;

	int bytes, size;



		if (size >= 4) {

			if (host->data->flags & MMC_DATA_READ)

				*(u32*)buffer = readl(host->ioaddr + SDHCI_BUFFER);

			else

				writel(*(u32*)buffer, host->ioaddr + SDHCI_BUFFER);

			size = 4;

		} else if (size >= 2) {

			if (host->data->flags & MMC_DATA_READ)

				*(u16*)buffer = readw(host->ioaddr + SDHCI_BUFFER);

			else

				writew(*(u16*)buffer, host->ioaddr + SDHCI_BUFFER);

			size = 2;

		} else {

			if (host->data->flags & MMC_DATA_READ)

				*(u8*)buffer = readb(host->ioaddr + SDHCI_BUFFER);

			else

				writeb(*(u8*)buffer, host->ioaddr + SDHCI_BUFFER);

			size = 1;

		}

	DBG("PIO writing\n");



	blksize = host->data->blksz;

	chunk_remain = 4;

	data = 0;



		buffer += size;

	bytes = 0;

	buffer = sdhci_kmap_sg(host) + host->offset;



	while (blksize) {

		size = min(host->size, host->remain);

		size = min(size, chunk_remain);



		chunk_remain -= size;

		blksize -= size;

		host->offset += size;

		host->remain -= size;



		bytes += size;

		host->size -= size;

		while (size) {

			data >>= 8;

			data |= (u32)*buffer << 24;

			buffer++;

			size--;

		}



		if (chunk_remain == 0) {

			writel(data, host->ioaddr + SDHCI_BUFFER);

			chunk_remain = min(blksize, 4);

		}



		if (host->remain == 0) {

			sdhci_kunmap_sg(host);

			if (sdhci_next_sg(host) == 0) {

				DBG("PIO transfer: %d bytes\n", bytes);

				BUG_ON(blksize != 0);

				return;

			}

			buffer = sdhci_kmap_sg(host);
@@ -269,8 +280,35 @@ static void sdhci_transfer_pio(struct sdhci_host *host) 
	}



	sdhci_kunmap_sg(host);

}



static void sdhci_transfer_pio(struct sdhci_host *host)

{

	u32 mask;



	BUG_ON(!host->data);



	if (host->size == 0)

		return;



	if (host->data->flags & MMC_DATA_READ)

		mask = SDHCI_DATA_AVAILABLE;

	else

		mask = SDHCI_SPACE_AVAILABLE;



	while (readl(host->ioaddr + SDHCI_PRESENT_STATE) & mask) {

		if (host->data->flags & MMC_DATA_READ)

			sdhci_read_block_pio(host);

		else

			sdhci_write_block_pio(host);



		if (host->size == 0)

			break;



		BUG_ON(host->num_sg == 0);

	}



	DBG("PIO transfer: %d bytes\n", bytes);

	DBG("PIO transfer complete.\n");

}



static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data)
@@ -863,7 +901,7 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask) 
	if (host->data->error != MMC_ERR_NONE)

		sdhci_finish_data(host);

	else {

		if (intmask & (SDHCI_INT_BUF_FULL | SDHCI_INT_BUF_EMPTY))

		if (intmask & (SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL))

			sdhci_transfer_pio(host);



		if (intmask & SDHCI_INT_DATA_END)

drivers/mmc/sdhci.h

+3 −3
Original line number Diff line number Diff line
@@ -95,8 +95,8 @@ 
#define  SDHCI_INT_RESPONSE	0x00000001

#define  SDHCI_INT_DATA_END	0x00000002

#define  SDHCI_INT_DMA_END	0x00000008

#define  SDHCI_INT_BUF_EMPTY	0x00000010

#define  SDHCI_INT_BUF_FULL	0x00000020

#define  SDHCI_INT_SPACE_AVAIL	0x00000010

#define  SDHCI_INT_DATA_AVAIL	0x00000020

#define  SDHCI_INT_CARD_INSERT	0x00000040

#define  SDHCI_INT_CARD_REMOVE	0x00000080

#define  SDHCI_INT_CARD_INT	0x00000100
@@ -116,7 +116,7 @@ 
#define  SDHCI_INT_CMD_MASK	(SDHCI_INT_RESPONSE | SDHCI_INT_TIMEOUT | \

		SDHCI_INT_CRC | SDHCI_INT_END_BIT | SDHCI_INT_INDEX)

#define  SDHCI_INT_DATA_MASK	(SDHCI_INT_DATA_END | SDHCI_INT_DMA_END | \

		SDHCI_INT_BUF_EMPTY | SDHCI_INT_BUF_FULL | \

		SDHCI_INT_DATA_AVAIL | SDHCI_INT_SPACE_AVAIL | \

		SDHCI_INT_DATA_TIMEOUT | SDHCI_INT_DATA_CRC | \

		SDHCI_INT_DATA_END_BIT)