[U-Boot] __mmc_get_env_addr() is not being called?

[Fabio Estevam]

On Fri, Dec 16, 2011 at 3:54 AM, Shawn Guo <shawn.guo at freescale.com> wrote:
> Hi,
>
> I'm running v2011.12-rc1 (with one missing usdhc patch applied) on
> mx6qarm2 board, and seeing a problem.  When I install u-boot on a
> blank SD card, it boots fine with messge "*** Warning - bad CRC,
> using default environment" seen as expected.  But once I run command
> 'save' to write envs to the card, the card stop booting.

This is the same behavior I saw on mx28evk as well and I sent this
patch to fix it:
http://lists.denx.de/pipermail/u-boot/2011-November/111448.html

>
> I tracked the issue a little bit, and found __mmc_get_env_addr() does
> not get called at all.  Therefore when I run 'save' for the first time,
> the envs are written to offset 0 of the card, which in turn overwrites
> the boot image.
>
> I have not figured out why it does.  But the following change fixes
> the problem for me.
>
> diff --git a/common/env_mmc.c b/common/env_mmc.c
> index 8441c77..3832fe4 100644
> --- a/common/env_mmc.c
> +++ b/common/env_mmc.c
> @@ -46,13 +46,11 @@ DECLARE_GLOBAL_DATA_PTR;
>  #define CONFIG_ENV_OFFSET 0
>  #endif
>
> -static int __mmc_get_env_addr(struct mmc *mmc, u32 *env_addr)
> +static int mmc_get_env_addr(struct mmc *mmc, u32 *env_addr)
>  {
>        *env_addr = CONFIG_ENV_OFFSET;
>        return 0;
>  }
> -int mmc_get_env_addr(struct mmc *mmc, u32 *env_addr)
> -       __attribute__((weak, alias("__mmc_get_env_addr")));
>
> Any comment on why the change fixes the problem is appreciated.

The weak function was introduced by this commit:
http://git.denx.de/?p=u-boot.git;a=commitdiff;h=97039ab98c551c7860bc0977d684ef686159e0d7

which breaks non CONFIG_FSL_ESDHC users.

Regards,

Fabio Estevam