[PATCH 4/4] configs: visionfive2: enable SPL_YMODEM_SUPPORT

[E Shattow]

On Wed, Apr 17, 2024 at 1:22 AM Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> wrote:
>
> On 17.04.24 03:41, E Shattow wrote:
> > Successful in use w/ 'tio' serial tool and Adafruit CP2102N Friend
> > adapter on Mars CM Lite board in DFRobot mini router carrier.
> >
> > While SPL and u-boot.itb payload are sourced via UART the environment
> > variables are from the environment variable storage as-is. This makes
> > sense in the use case for development but may have side-effects in the
> > case of U-Boot as a JH7110 recovery tool. There is now 'env default -f
> > -a' which does not purge non-default variables and retains the
> > non-default variables when migrating from vendor firmware. Consider to
> > also build for U-Boot the commands that can aid in cleaning the stored
> > environment variable state CONFIG_CMD_ERASEENV=y and in-memory state
> > CONFIG_CMD_NVEDIT_LOAD=y. With these it can be done easily with: 'env
> > erase; env load; env save'.
>
> Thank you for testing.
>
> After erasing there is no need to save the environment. If there is no
> environment on flash, the default will be loaded anyway:
>
>    *** Warning - bad CRC, using default environment
>
> Instead of 'env erase' you could use 'sf erase 0xf0000 0x1000' which is
> already available. As adding CONFIG_CMD_ERASEENV=y is not necessary in
> the scope of this patch series I would prefer leaving it to future
> discussion.
>
> Best regards
>
> Heinrich
>

The 'env erase; env load; env save' can be done at the same session
just before recovery write to provide a sanitized environment with the
defaults of the present U-Boot payload loaded via UART, so is not the
same as 'sf erase ...' waiting for a reboot (5 minutes more to
transfer via UART at 115200 baud) and needing to interrupt the boot to
further 'env save'. Having 'env load' allows to allow that reboot step
in-between. Point taken though, it's helpful for recovery but not
required. -E