[PATCH] configs: rockchip: rock5b: enable environment

[Quentin Schulz]

Hi all,

On 3/5/24 10:36, Christopher Obbard wrote:
> [You don't often get email from chris.obbard at collabora.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> 
> Hi Jonas & Trevor,
> 
> On Tue, 2024-03-05 at 10:31 +0100, Jonas Karlman wrote:
>> Hi Trevor,
>>
>> On 2024-03-05 03:10, Trevor Woerner wrote:
>>> Following the pattern of other Rockchip devices, enable the U-Boot
>>> environment to be stored in MMC. This patch specifically assumes the
>>> environment will be stored on the SDcard.
>>
>> This board has SPI flash, so storing env in SPI flash is probably a
>> better default.
> 
> I agree with that.
> 
>> However, preferably the env should be stored/loaded from
>> the same device that TPL/SPL was loaded from.
> 
> Do you know if there is some mechanism in U-Boot to do this already ?
> 

We do this for our Theobroma boards, though we use the same device that 
U-Boot proper was loaded from, and not the one that TPL+SPL was loaded 
from but the logic could be more or less the same.

https://source.denx.de/u-boot/u-boot/-/blob/master/board/theobroma-systems/common/common.c?ref_type=heads#L92-L152

is what you need. The first function is to differentiate between SD card 
and eMMC, the second actually returns the **kind** of medium the 
environment is stored on (so MMC or SPI-flash for Theobroma boards).

Instead of 
https://source.denx.de/u-boot/u-boot/-/blob/master/board/theobroma-systems/common/common.c?ref_type=heads#L94-L95 
you probably want to use board_spl_was_booted_from().

Note that to you need the MMC and SPI controllers to be bound in U-Boot 
proper **before relocation** for this to work. c.f. 
https://lore.kernel.org/u-boot/20240221-jaguar-v3-15-1f256a82201b@theobroma-systems.com/

> It could be useful to enable autodetection on many boards which can boot U-
> Boot from either SPI flash / eMMC / SD card.
> 

There's been an attempt recently:

https://lore.kernel.org/u-boot/20240226011413.435713-2-benwolsieffer@gmail.com/

though only for the MMC part of the equation.

Cheers,
Quentin