Re: [PATCH v3 1/2] env: mmc: Make redundant env in both eMMC boot partitions consider DT properties

[Quentin Schulz <quentin.schulz@cherry.de>]

Hi Marek,

On 2/21/25 7:47 PM, Marek Vasut wrote:
> Introduce a new function mmc_env_is_redundant_in_both_boot_hwparts()
> which replaces IS_ENABLED(ENV_MMC_HWPART_REDUND) and internally does
> almost the same check as the macro which assigned ENV_MMC_HWPART_REDUND
> did, and call it in place of IS_ENABLED(ENV_MMC_HWPART_REDUND).
> 
> The difference compared to IS_ENABLED(ENV_MMC_HWPART_REDUND) is
> in the last conditional, which does not do plain macro compare
> (CONFIG_ENV_OFFSET == CONFIG_ENV_OFFSET_REDUND), but instead does
> mmc_offset(mmc, 0) == mmc_offset(mmc, 1). If OF_CONTROL is not
> in use, this gets optimized back to original macro compare, but
> if OF_CONTROL is in use, this also takes into account the DT
> properties u-boot,mmc-env-offset and u-boot,mmc-env-offset-redundant.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> ---
> Cc: Dragan Simic <dsimic@manjaro.org>
> Cc: Joe Hershberger <joe.hershberger@ni.com>
> Cc: Mattijs Korpershoek <mkorpershoek@baylibre.com>
> Cc: Quentin Schulz <quentin.schulz@cherry.de>
> Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Tom Rini <trini@konsulko.com>
> Cc: u-boot@lists.denx.de
> ---
> V2: - Rename mmc_env_hwpart_redund() to mmc_env_is_redundant_in_both_boot_hwparts()
>      - Return bool
> V3: - Hide the mmc_env_is_redundant_in_both_boot_hwparts symbol behind __maybe_unused
>        as this symbol is called from code gated behind ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
>        in env_mmc_load()
> ---
>   env/mmc.c | 37 +++++++++++++++++++++----------------
>   1 file changed, 21 insertions(+), 16 deletions(-)
> 
> diff --git a/env/mmc.c b/env/mmc.c
> index 379f5ec9be7..353a7ce72fb 100644
> --- a/env/mmc.c
> +++ b/env/mmc.c
> @@ -40,18 +40,6 @@
>   
>   DECLARE_GLOBAL_DATA_PTR;
>   
> -/*
> - * In case the environment is redundant, stored in eMMC hardware boot
> - * partition and the environment and redundant environment offsets are
> - * identical, store the environment and redundant environment in both
> - * eMMC boot partitions, one copy in each.
> - * */
> -#if (defined(CONFIG_SYS_REDUNDAND_ENVIRONMENT) && \
> -     (CONFIG_SYS_MMC_ENV_PART == 1) && \
> -     (CONFIG_ENV_OFFSET == CONFIG_ENV_OFFSET_REDUND))
> -#define ENV_MMC_HWPART_REDUND	1
> -#endif
> -
>   #if CONFIG_IS_ENABLED(OF_CONTROL)
>   
>   static int mmc_env_partition_by_name(struct blk_desc *desc, const char *str,
> @@ -217,6 +205,23 @@ static inline s64 mmc_offset(struct mmc *mmc, int copy)
>   }
>   #endif
>   
> +static bool __maybe_unused mmc_env_is_redundant_in_both_boot_hwparts(struct mmc *mmc)
> +{
> +	/*
> +	 * In case the environment is redundant, stored in eMMC hardware boot
> +	 * partition and the environment and redundant environment offsets are
> +	 * identical, store the environment and redundant environment in both
> +	 * eMMC boot partitions, one copy in each.
> +	 */
> +	if (!IS_ENABLED(CONFIG_SYS_REDUNDAND_ENVIRONMENT))
> +		return false;
> +
> +	if (CONFIG_SYS_MMC_ENV_PART != 1)
> +		return false;
> +
> +	return mmc_offset(mmc, 0) == mmc_offset(mmc, 1);

This is not always equivalent to the current test of

CONFIG_ENV_OFFSET == CONFIG_ENV_OFFSET_REDUND

Indeed, it only is for when OF_CONTROL isn't set.

I would recommend to keep this check in patch 1, then add another patch 
that swaps CONFIG_ENV_OFFSET == CONFIG_ENV_OFFSET_REDUND for 
mmc_offset(mmc, 0) == mmc_offset(mmc, 1)

This will allow to use DT properties like 
u-boot,mmc-env-offset-redundant and u-boot,mmc-env-offset, which isn't 
supported today.

What do you think?

The rest of the diff looks good to me.

Cheers,
Quentin