[PATCH 01/12] env: Complete generic support for writable list

[Jan Kiszka]

On 29.05.22 03:46, Marek Vasut wrote:
> On 5/28/22 15:02, Jan Kiszka wrote:
>> From: Jan Kiszka <jan.kiszka at siemens.com>
>>
>> This completes what 890feecaab72 started by selecting ENV_APPEND and
>> ENV_IS_NOWHERE and by moving this driver to top if the list. This
> 
> s at if the list at of the list@
> 
>> ensures that load operations pick up both the default env and the
>> permitted parts of the next-prio location. When writing though, we must
>> not use NOWHERE and rather need to forward directly to the first
>> external location.
> 
> Isn't the env load order a board-specific setting ?
> 

There can always be special cases, but I don't see why it should be
_always_ board-specific.

>> With this change, boards only need to define the list of writable
>> variables but no longer have to provide a custom env_get_location
>> implementation.
> 
> This also brings in a lot of ifdeffery and extra complexity. If you
> implement this as a board-specific env_get_location() override, you can
> avoid that. Try:
> 
> enum env_location env_get_location(enum env_operation op, int prio)
> {
>          if (op == ENVOP_SAVE) {
>                  if (prio == 0)
>                          return ENVL_SPI_FLASH;
>          } else {
>                  if (prio == 0)
>                          return ENVL_NOWHERE;
>                  if (prio == 1)
>                          return ENVL_SPI_FLASH;
>          }
> 
>          return ENVL_UNKNOWN;
> }

This is exactly what I would like to avoid, having to carry such a
generic function (minus that hard-coded the choice of storage - this can
be controlled via .config) in every board.

Jan

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