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

On 01/11/2013 12:26 AM, Simon Glass wrote:

Hi Amar,

On Fri, Jan 4, 2013 at 1:34 AM, Amar amarendra.xt@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@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?

i didn't sure why add the mdelay(1)..i think mdelay(1) is too long. Isn't there other approach to resolve read/write issue?

Best Regards, Jaehoon Chung

...

    }

    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