[U-Boot] [PATCH V3 3/9] DWMMC: Initialise dwmci and resolve EMMC read write issues

Amar amarendra.xt at samsung.com
Mon Dec 31 11:58:14 CET 2012


This patch enumerates dwmci and set auto stop command during
dwmci initialisation.
EMMC read/write is not happening in current implementation
due to improper fifo size computation. Hence Modified the fifo size
computation to resolve EMMC read write issues.

Changes from V1:
	1)Created the macros RX_WMARK_SHIFT and RX_WMARK_MASK in header file.

Changes from V2:
	1)Updation of commit message and resubmition of proper patch set.

Signed-off-by: Amar <amarendra.xt at samsung.com>
---
 drivers/mmc/dw_mmc.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
index 4070d4e..d8fa1a2 100644
--- a/drivers/mmc/dw_mmc.c
+++ b/drivers/mmc/dw_mmc.c
@@ -136,6 +136,7 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
 			return TIMEOUT;
 		}
 		timeout--;
+		mdelay(1);
 	}
 
 	dwmci_writel(host, DWMCI_RINTSTS, DWMCI_INTMSK_ALL);
@@ -314,7 +315,7 @@ static void dwmci_set_ios(struct mmc *mmc)
 static int dwmci_init(struct mmc *mmc)
 {
 	struct dwmci_host *host = (struct dwmci_host *)mmc->priv;
-	u32 fifo_size, fifoth_val;
+	u32 fifo_size, fifoth_val, ier;
 
 	dwmci_writel(host, DWMCI_PWREN, 1);
 
@@ -323,6 +324,14 @@ static int dwmci_init(struct mmc *mmc)
 		return -1;
 	}
 
+	/* Enumerate at 400KHz */
+	dwmci_setup_bus(host, mmc->f_min);
+
+	/* Set auto stop command */
+	ier = dwmci_readl(host, DWMCI_CTRL);
+	ier |= (1<<10);
+	dwmci_writel(host, DWMCI_CTRL, ier);
+
 	dwmci_writel(host, DWMCI_RINTSTS, 0xFFFFFFFF);
 	dwmci_writel(host, DWMCI_INTMASK, 0);
 
@@ -332,10 +341,11 @@ static int dwmci_init(struct mmc *mmc)
 	dwmci_writel(host, DWMCI_BMOD, 1);
 
 	fifo_size = dwmci_readl(host, DWMCI_FIFOTH);
+	fifo_size = ((fifo_size & RX_WMARK_MASK) >> RX_WMARK_SHIFT) + 1;
 	if (host->fifoth_val)
 		fifoth_val = host->fifoth_val;
 	else
-		fifoth_val = MSIZE(0x2) | RX_WMARK(fifo_size/2 -1) |
+		fifoth_val = MSIZE(0x2) | RX_WMARK(fifo_size/2 - 1) |
 			TX_WMARK(fifo_size/2);
 	dwmci_writel(host, DWMCI_FIFOTH, fifoth_val);
 
-- 
1.8.0



More information about the U-Boot mailing list