Re: [[PATCH v2] 7/7] EmbeddedPkg: Fix DwEmmc driver bugs

["Leif Lindholm" <leif.lindholm@linaro.org>]

On Fri, May 03, 2019 at 11:27:03AM +0800, tien.hock.loh@intel.com wrote:
> From: "Tien Hock, Loh" <tien.hock.loh@intel.com>
> 
> Add support for reading data that is less than DWEMMC_BLOCK_SIZE, otherwise
> it would read bigger data than requested and cause errors
> 
> Signed-off-by: "Tien Hock, Loh" <tien.hock.loh@intel.com>
> Cc: Leif Lindholm <leif.lindholm@linaro.org>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
>  EmbeddedPkg/Drivers/DwEmmcDxe/DwEmmcDxe.c | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/EmbeddedPkg/Drivers/DwEmmcDxe/DwEmmcDxe.c b/EmbeddedPkg/Drivers/DwEmmcDxe/DwEmmcDxe.c
> index c38b5a4..4183ad4 100644
> --- a/EmbeddedPkg/Drivers/DwEmmcDxe/DwEmmcDxe.c
> +++ b/EmbeddedPkg/Drivers/DwEmmcDxe/DwEmmcDxe.c
> @@ -495,7 +495,10 @@ PrepareDmaData (
>  
>    Cnt = (Length + DWEMMC_DMA_BUF_SIZE - 1) / DWEMMC_DMA_BUF_SIZE;
>    Blks = (Length + DWEMMC_BLOCK_SIZE - 1) / DWEMMC_BLOCK_SIZE;

Could we add a BlockSize variable instead?...

> -  Length = DWEMMC_BLOCK_SIZE * Blks;
> +
> +  if(Length >= DWEMMC_BLOCK_SIZE) {
> +    Length = DWEMMC_BLOCK_SIZE * Blks;
> +  }
>  
>    for (Idx = 0; Idx < Cnt; Idx++) {
>      (IdmacDesc + Idx)->Des0 = DWEMMC_IDMAC_DES0_OWN | DWEMMC_IDMAC_DES0_CH |
> @@ -533,11 +536,18 @@ StartDma (
>    Data |= DWEMMC_CTRL_INT_EN | DWEMMC_CTRL_DMA_EN | DWEMMC_CTRL_IDMAC_EN;
>    MmioWrite32 (DWEMMC_CTRL, Data);
>    Data = MmioRead32 (DWEMMC_BMOD);
> +

Drop unrelated whitespace addition.

>    Data |= DWEMMC_IDMAC_ENABLE | DWEMMC_IDMAC_FB;
>    MmioWrite32 (DWEMMC_BMOD, Data);
>

And do
  if (Length < DWEMMC_BLOCK_SIZE) {
    BlockSize = Length;
  } else {
    BlockSize = DWEMMC_BLOCK_SIZE;
  }

  MmioWrite32 (DWEMMC_BLKSIZ, BlockSize);
  MmioWrite32 (DWEMMC_BYTCNT, Length);      
instead?

(I have no comments on the patches I have not responded to at this
point, but I want to see their proper subject lines before giving a R-b:)

/
    Leif

> -  MmioWrite32 (DWEMMC_BLKSIZ, DWEMMC_BLOCK_SIZE);
> -  MmioWrite32 (DWEMMC_BYTCNT, Length);
> +  if(Length < DWEMMC_BLOCK_SIZE) {
> +    MmioWrite32 (DWEMMC_BLKSIZ, Length);
> +    MmioWrite32 (DWEMMC_BYTCNT, Length);
> +  }
> +  else {
> +    MmioWrite32 (DWEMMC_BLKSIZ, DWEMMC_BLOCK_SIZE);
> +    MmioWrite32 (DWEMMC_BYTCNT, Length);
> +  }
>  }
>  
>  EFI_STATUS
> -- 
> 2.2.2
>