[PATCH] imx9: Improve boot device auto-selection

[Szőke Benjamin]

2024. 10. 16. 21:41 keltezéssel, Szőke Benjamin írta:
> 2024. 10. 16. 20:28 keltezéssel, Fabio Estevam írta:
>> Benjamin,
>>
>> On Sun, Oct 13, 2024 at 9:39 PM Peng Fan <peng.fan at nxp.com> wrote:
>>
>>> Would you please give more background on this, I not got
>>> the point on why doing this?
>>
>> I also do not understand the reason for this change. It is not clear
>> by reading the commit log.
>>
>> Please describe what exactly fails to work before the patch and what
>> works after your change.
>>
>>>> +#ifndef CONFIG_SYS_MMC_ENV_DEV
>>>> +#define CONFIG_SYS_MMC_ENV_DEV 0
>>>> +#endif
>>
>> I don't understand the need for this.
>>
>> env/Kconfig has a default 0 for SYS_MMC_ENV_DEV.
> 
> 
> You can use only one of config from CONFIG_ENV_IS_IN_MMC=y and 
> CONFIG_ENV_IS_NOWHERE=y in U-boot config in same time.
> 
> If you like to use CONFIG_ENV_IS_NOWHERE=y, these codes in the patched source 
> files will be not part of the build, and the autodetection of the boot mode will 
> never work. At the moment it works only if you use CONFIG_ENV_IS_IN_MMC=y in U- 
> boot config but it should work also in case of use CONFIG_ENV_IS_NOWHERE=y 
> option also.
> 
> Other poblem is that CONFIG_SYS_MMC_ENV_DEV can be defined only if 
> CONFIG_ENV_IS_IN_MMC=y is active in config of U-boot. It means, it needs to be 
> manually defined in case when CONFIG_ENV_IS_NOWHERE=y is used, because the codes 
> in the patched sources like to use it as a return value in some error/default 
> cases.
> 

Did you get what is the problem?

https://github.com/u-boot/u-boot/commit/636c95f82b9a184a9b45a8965488cea2dedcd78e
The implementation of mmc_get_env_dev() in arch/arm/mach-imx/imx9/soc.c is not 
able to support CONFIG_ENV_IS_NOWHERE=y using. It was fixed in my patch.