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

[Jaehoon Chung]

On 12/31/2012 07:58 PM, Amar wrote:
> 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.
What issue for read/write?
> 
> 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);
Why add the mdelay(1)? Could you explain to me?
>  	}
>  
>  	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);
Use the define..ex) define DWMCI_CTRL_AUTO_STOP_CMD 	BIT(10)
> +	dwmci_writel(host, DWMCI_CTRL, ier);
If set to auto stop command, then you didn't see any problem?

Best Regards,
Jaehoon Chung
> +
>  	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);
>  
>