[PATCH 12/13] sdhci: Add quirk for controllers with max. block size up to 4096 bytes

Anton Vorontsov avorontsov at ru.mvista.com
Sat Feb 14 01:47:39 EST 2009


FSL eSDHC controllers can support maximum block size up to 4096
bytes. The MBL (Maximum Block Length) field in the capabilities
register extended by one bit, and bits 13:15 in the block size
register reserved.

Signed-off-by: Anton Vorontsov <avorontsov at ru.mvista.com>
---
 drivers/mmc/host/sdhci.c |   28 ++++++++++++++++++++--------
 drivers/mmc/host/sdhci.h |    2 ++
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index b308dbf..b341a9a 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -682,6 +682,7 @@ static void sdhci_set_transfer_irqs(struct sdhci_host *host)
 
 static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data)
 {
+	u16 blksz;
 	u8 count;
 	u8 ctrl;
 	int ret;
@@ -831,7 +832,12 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data)
 	sdhci_set_transfer_irqs(host);
 
 	/* We do not handle DMA boundaries, so set it to max (512 KiB) */
-	sdhci_writew(host, SDHCI_MAKE_BLKSZ(7, data->blksz), SDHCI_BLOCK_SIZE);
+	if (host->quirks & SDHCI_QUIRK_MAX_BLK_SZ_4096)
+		blksz = data->blksz;
+	else
+		blksz = SDHCI_MAKE_BLKSZ(7, data->blksz);
+
+	sdhci_writew(host, blksz, SDHCI_BLOCK_SIZE);
 	sdhci_writew(host, data->blocks, SDHCI_BLOCK_COUNT);
 }
 
@@ -1840,13 +1846,19 @@ int sdhci_add_host(struct sdhci_host *host)
 	 * Maximum block size. This varies from controller to controller and
 	 * is specified in the capabilities register.
 	 */
-	mmc->max_blk_size = (caps & SDHCI_MAX_BLOCK_MASK) >> SDHCI_MAX_BLOCK_SHIFT;
-	if (mmc->max_blk_size >= 3) {
-		printk(KERN_WARNING "%s: Invalid maximum block size, "
-			"assuming 512 bytes\n", mmc_hostname(mmc));
-		mmc->max_blk_size = 512;
-	} else
-		mmc->max_blk_size = 512 << mmc->max_blk_size;
+	if (host->quirks & SDHCI_QUIRK_MAX_BLK_SZ_4096) {
+		mmc->max_blk_size = 3;
+	} else {
+		mmc->max_blk_size = (caps & SDHCI_MAX_BLOCK_MASK) >>
+				SDHCI_MAX_BLOCK_SHIFT;
+		if (mmc->max_blk_size >= 3) {
+			printk(KERN_WARNING "%s: Invalid maximum block size, "
+				"assuming 512 bytes\n", mmc_hostname(mmc));
+			mmc->max_blk_size = 0;
+		}
+	}
+
+	mmc->max_blk_size = 512 << mmc->max_blk_size;
 
 	/*
 	 * Maximum block count.
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 5c5a950..c8628b4 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -231,6 +231,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK_PIO_NEEDS_DELAY			(1<<20)
 /* Controller losing signal/interrupt enable states after reset */
 #define SDHCI_QUIRK_RESTORE_IRQS_AFTER_RESET		(1<<21)
+/* Controller supports nonstandard maximum block length of 4096 bytes */
+#define SDHCI_QUIRK_MAX_BLK_SZ_4096			(1<<22)
 
 	int			irq;		/* Device IRQ */
 	void __iomem *		ioaddr;		/* Mapped address */
-- 
1.5.6.5




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