[U-Boot] [PATCH 1/3] efi_loader: correctly determine if an MMC device is an SD-card

[Alexander Graf]

On 02.12.17 13:42, Heinrich Schuchardt wrote:
> The SD cards and eMMC devices have different device nodes.
> The current coding interpretes all MMC devices as eMMC.
> 
> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
> ---
>  lib/efi_loader/efi_device_path.c | 24 +++++++++++++++++++++---
>  1 file changed, 21 insertions(+), 3 deletions(-)
> 
> diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c
> index b4e2f933cb..42fe6e1185 100644
> --- a/lib/efi_loader/efi_device_path.c
> +++ b/lib/efi_loader/efi_device_path.c
> @@ -36,6 +36,24 @@ static const struct efi_device_path_vendor ROOT = {
>  	.guid = U_BOOT_GUID,
>  };
>  
> +#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
> +/*
> + * Determine if an MMC device is an SD card.
> + *
> + * @desc	block device descriptor
> + * @return	true if the device is an SD card
> + */
> +static bool is_sd(struct blk_desc *desc)
> +{
> +	struct mmc *mmc = find_mmc_device(desc->devnum);
> +
> +	if (!mmc)
> +		return false;
> +
> +	return IS_SD(mmc) != 0U;
> +}
> +#endif
> +
>  static void *dp_alloc(size_t sz)
>  {
>  	void *buf;
> @@ -298,9 +316,9 @@ static void *dp_fill(void *buf, struct udevice *dev)
>  		struct blk_desc *desc = mmc_get_blk_desc(mmc);
>  
>  		sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
> -		sddp->dp.sub_type = (desc->if_type == IF_TYPE_MMC) ?
> -			DEVICE_PATH_SUB_TYPE_MSG_MMC :
> -			DEVICE_PATH_SUB_TYPE_MSG_SD;
> +		sddp->dp.sub_type = is_sd(desc) ?
> +			DEVICE_PATH_SUB_TYPE_MSG_SD :
> +			DEVICE_PATH_SUB_TYPE_MSG_MMC;

So in general, MMC != SD != eMMC. Or rather eMMC "is like" SD "is like"
MMC maybe?

I really don't know how edk2 distinguishes between them. In general,
eMMC is an SD card on steroids. Can you double-check in the edk2 code
and then we just do whatever they do?


Alex