Re: [PATCH v2] env: mmc: Make redundant env in both eMMC boot partitions consider DT properties

[Mattijs Korpershoek <mkorpershoek@baylibre.com>]

Hi Marek,

Thank you for the patch.

On mar., févr. 11, 2025 at 14:31, Marek Vasut <marex@denx.de> 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>

Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

Some question below.

> ---
> 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
> ---
>  env/mmc.c | 37 +++++++++++++++++++++----------------
>  1 file changed, 21 insertions(+), 16 deletions(-)
>
> diff --git a/env/mmc.c b/env/mmc.c
> index 379f5ec9be7..c4467333263 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 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;

Looking at the description of this KConfig entry:
"""
CONFIG_SYS_MMC_ENV_PART (optional):

Specifies which MMC partition the environment is stored in. If not
set, defaults to partition 0, the user area. Common values might be
1 (first MMC boot partition), 2 (second MMC boot partition).
"""

Makes me wonder: does this work when the environment is stored in the
second MMC boot partition ?

I'm not sure.

This is also out of scope for the patch though, since the original
#ifdefery already has this.

> +
> +	return mmc_offset(mmc, 0) == mmc_offset(mmc, 1);
> +}
> +
>  __weak int mmc_get_env_addr(struct mmc *mmc, int copy, u32 *env_addr)
>  {
>  	s64 offset = mmc_offset(mmc, copy);
> @@ -336,7 +341,7 @@ static int env_mmc_save(void)
>  		if (gd->env_valid == ENV_VALID)
>  			copy = 1;
>  
> -		if (IS_ENABLED(ENV_MMC_HWPART_REDUND)) {
> +		if (mmc_env_is_redundant_in_both_boot_hwparts(mmc)) {
>  			ret = mmc_set_env_part(mmc, copy + 1);
>  			if (ret)
>  				goto fini;
> @@ -409,7 +414,7 @@ static int env_mmc_erase(void)
>  	if (IS_ENABLED(CONFIG_SYS_REDUNDAND_ENVIRONMENT)) {
>  		copy = 1;
>  
> -		if (IS_ENABLED(ENV_MMC_HWPART_REDUND)) {
> +		if (mmc_env_is_redundant_in_both_boot_hwparts(mmc)) {
>  			ret = mmc_set_env_part(mmc, copy + 1);
>  			if (ret)
>  				goto fini;
> @@ -477,7 +482,7 @@ static int env_mmc_load(void)
>  		goto fini;
>  	}
>  
> -	if (IS_ENABLED(ENV_MMC_HWPART_REDUND)) {
> +	if (mmc_env_is_redundant_in_both_boot_hwparts(mmc)) {
>  		ret = mmc_set_env_part(mmc, 1);
>  		if (ret)
>  			goto fini;
> @@ -485,7 +490,7 @@ static int env_mmc_load(void)
>  
>  	read1_fail = read_env(mmc, CONFIG_ENV_SIZE, offset1, tmp_env1);
>  
> -	if (IS_ENABLED(ENV_MMC_HWPART_REDUND)) {
> +	if (mmc_env_is_redundant_in_both_boot_hwparts(mmc)) {
>  		ret = mmc_set_env_part(mmc, 2);
>  		if (ret)
>  			goto fini;
> -- 
> 2.47.2