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

Michal Simek michal.simek at xilinx.com
Tue May 31 09:40:24 CEST 2016


On 31.5.2016 08:39, Alexander Graf wrote:
> 
> 
>> Am 31.05.2016 um 07:04 schrieb Michal Simek <michal.simek at xilinx.com>:
>>
>>> On 30.5.2016 21:36, Alexander Graf wrote:
>>>
>>>
>>>> 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.
>>
>> Was there any environment in past?
> 
> With again I meant "from C as well as from script".
> 
>>>
>>> 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?
>>
>> If you expose environment variable and then run saveenv this variable
>> will be saved and restored again and your script behaves the same.
> 
> Not if we declare the environment variable read as callback ;).

What do you mean?

It is kind of interesting that this is not done already for others SoCs
when you want to use distro config. :-)

Cheers,
Michal




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