[U-Boot] [PATCH] env: Setup GD_FLG_ENV_DEFAULT flag when default environment are used

[Alexander Graf]

On 05/30/2016 04:11 PM, Michal Simek wrote:
> Setup flag when default environment are used to be able to
> rewrite default distro boot variables based on SoC boot mode.
>
> Signed-off-by: Michal Simek <michal.simek at xilinx.com>
> ---
>
> I didn't find any way how to detect that default or saved variables are
> used. I want to have a flag to be able to rewrite boot_targets variable
> based on boot mode. Especially when SD boot mode is setup than SD should
> be primary boot devices, etc.
> When variables are saved boot_targets will be restored and SoC boot mode
> will be ignored.
> If you know better way how to do it, please let me know.

You may want to be able to do the same from inside a script, so I guess 
we should better have this as an environment variable itself again.

There was a way to have environment variable reads return a value 
directly from code rather than go via environment storage. I guess we 
could expose the flag through that?

Or add an environment variable that we set in set_default_env() and 
ignore that variable on saveenv. I'm not sure I like that option better 
than your current one though.


Alex

>
> ---
>   common/env_common.c               | 1 +
>   include/asm-generic/global_data.h | 1 +
>   2 files changed, 2 insertions(+)
>
> diff --git a/common/env_common.c b/common/env_common.c
> index af59c72e1fd7..13db7dc3f755 100644
> --- a/common/env_common.c
> +++ b/common/env_common.c
> @@ -123,6 +123,7 @@ void set_default_env(const char *s)
>   		error("Environment import failed: errno = %d\n", errno);
>   
>   	gd->flags |= GD_FLG_ENV_READY;
> +	gd->flags |= GD_FLG_ENV_DEFAULT;
>   }
>   
>   
> diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
> index f2810a1bd75f..0abcbe4c0b3a 100644
> --- a/include/asm-generic/global_data.h
> +++ b/include/asm-generic/global_data.h
> @@ -141,5 +141,6 @@ typedef struct global_data {
>   #define GD_FLG_SPL_INIT		0x00400	/* spl_init() has been called	   */
>   #define GD_FLG_SKIP_RELOC	0x00800	/* Don't relocate */
>   #define GD_FLG_RECORD		0x01000	/* Record console */
> +#define GD_FLG_ENV_DEFAULT	0x02000 /* Default variable flag */
>   
>   #endif /* __ASM_GENERIC_GBL_DATA_H */