[U-Boot] [PATCH] arm: socfpga: control reboot from SRAM via env callback

[Marek Vasut]

On 5/3/19 10:39 PM, Simon Goldschmidt wrote:
> 
> 
> On 03.05.19 22:35, Marek Vasut wrote:
>> On 5/3/19 10:30 PM, Simon Goldschmidt wrote:
>>>
>>>
>>> On 03.05.19 22:28, Marek Vasut wrote:
>>>> On 5/3/19 10:08 PM, Simon Goldschmidt wrote:
>>>>> This moves the code that enables the Boot ROM to just jump to SRAM
>>>>> instead
>>>>> of loading SPL from the original boot source on warm reboot.
>>>>>
>>>>> Instead of always enabling this, an environment callback for the
>>>>> env var
>>>>> "socfpga_reboot_from_sram" is used. This way, the behaviour can be
>>>>> enabled
>>>>> at runtime and via saved environment.
>>>>>
>>>>> Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt at gmail.com>
>>>>
>>>> Would that be like a default "reset" command action ?
>>>> This probably shouldn't be socfpga specific then.
>>>
>>> No, it's a thing that lives on and influences even the soft reset issued
>>> by linux "reboot" command. This is something *very* socfpga specific.
>>
>> Hmmm, so isn't this a policy to be configured on the Linux end ?
> 
> Might be, but it affects U-Boot's 'reset' command as well. And I guess
> it's set up in U-Boot this early to ensure it always works.

Drat, that's right. So there has to be some way to agree on how the
reset works between the kernel and U-Boot ?

> If it were for me, we could drop writing this magic altogether. I just
> figured some boards might require it to be written somewhere, and came
> up with a patch that might save those boards with the way it was before.

Isn't this magic actually used by bootrom ?

-- 
Best regards,
Marek Vasut