[U-Boot] [PATCH V4 3/9] DWMMC: Initialise dwmci and resolve EMMC read write issues

[Simon Glass]

Hi Amar,

On Fri, Jan 4, 2013 at 1:34 AM, Amar <amarendra.xt at samsung.com> 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.
>
> 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.
>
> Changes from V3:
>         1)Updated to use the macro DWMCI_CTRL_SEND_AS_CCSD instead of
>         the hard coded value (1 << 10).

I suggest you take a look at patman which might simplify your patch
sending and change logs - see tools/patman/README for details.

>
> 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..776fdb6 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);

How long will this delay in total?

>         }
>
>         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 |= DWMCI_CTRL_SEND_AS_CCSD;
> +       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);

{} around this else I think. Also space around /

>         dwmci_writel(host, DWMCI_FIFOTH, fifoth_val);
>
> --
> 1.8.0
>

Regards,
Simon