From: Amar <amarendra...@samsung.com>

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.

Signed-off-by: Amar <amarendra...@samsung.com>
---
Changes since V1:
        1)Created the macros RX_WMARK_SHIFT and RX_WMARK_MASK in header file.

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

Changes since V3:
        1)Updated to use the macro DWMCI_CTRL_SEND_AS_CCSD instead of
        the hard coded value (1 << 10).

Changes since V4:
        1)Updated the function dwmci_send_cmd() to use get_timer() instead
        of using mdelay(1).

Changes since V5:
        1)Updated in response to review comments.

Changes since V6:
        No change.

Changes since V7:
        1)Updated the function dwmci_setup_bus() to return 0 if (freq == 0). 
        This is to avoid the run time exception "raise:Signal # 8 caught".

Changes since V8:
        1)Auto stop command is disabled, as this feature is not required.

---
 drivers/mmc/dw_mmc.c |   21 ++++++++++++---------
 1 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
index 4070d4e..1307b12 100644
--- a/drivers/mmc/dw_mmc.c
+++ b/drivers/mmc/dw_mmc.c
@@ -129,13 +129,13 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd 
*cmd,
        unsigned int timeout = 100000;
        u32 retry = 10000;
        u32 mask, ctrl;
+       ulong start = get_timer(0);
 
        while (dwmci_readl(host, DWMCI_STATUS) & DWMCI_BUSY) {
-               if (timeout == 0) {
+               if (get_timer(start) > timeout) {
                        printf("Timeout on data busy\n");
                        return TIMEOUT;
                }
-               timeout--;
        }
 
        dwmci_writel(host, DWMCI_RINTSTS, DWMCI_INTMSK_ALL);
@@ -143,7 +143,6 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd 
*cmd,
        if (data)
                dwmci_prepare_data(host, data);
 
-
        dwmci_writel(host, DWMCI_CMDARG, cmd->cmdarg);
 
        if (data)
@@ -231,9 +230,8 @@ static int dwmci_setup_bus(struct dwmci_host *host, u32 
freq)
        int timeout = 10000;
        unsigned long sclk;
 
-       if (freq == host->clock)
+       if ((freq == host->clock) || (freq == 0))
                return 0;
-
        /*
         * If host->mmc_clk didn't define,
         * then assume that host->bus_hz is source clock value.
@@ -323,6 +321,9 @@ static int dwmci_init(struct mmc *mmc)
                return -1;
        }
 
+       /* Enumerate at 400KHz */
+       dwmci_setup_bus(host, mmc->f_min);
+
        dwmci_writel(host, DWMCI_RINTSTS, 0xFFFFFFFF);
        dwmci_writel(host, DWMCI_INTMASK, 0);
 
@@ -332,11 +333,13 @@ static int dwmci_init(struct mmc *mmc)
        dwmci_writel(host, DWMCI_BMOD, 1);
 
        fifo_size = dwmci_readl(host, DWMCI_FIFOTH);
-       if (host->fifoth_val)
+       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) |
-                       TX_WMARK(fifo_size/2);
+       } else {
+               fifoth_val = MSIZE(0x2) | RX_WMARK(fifo_size / 2 - 1) |
+                       TX_WMARK(fifo_size / 2);
+       }
        dwmci_writel(host, DWMCI_FIFOTH, fifoth_val);
 
        dwmci_writel(host, DWMCI_CLKENA, 0);
-- 
1.7.3.rc2

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