DWMMC: Initialise dwmci and resolve EMMC read write issues

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.xt@samsung.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>

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);