[U-Boot] [PATCH 2/2] env: Add back default action of get_char in env_get_char()

[Goldschmidt Simon]

Maxime, York,

I've just sent a patch that removes 'get_char' callback from the env 
drivers. This should restore the old behaviour we had before supporting 
multiple environment drivers (for all but eeprom, of course).


Simon


On 08.02.2018 23:10, Maxime Ripard wrote:
> On Thu, Feb 08, 2018 at 10:52:20AM +0100, Simon Goldschmidt wrote:
>> On 08.02.2018 09:47, Maxime Ripard wrote:
>>> On Wed, Feb 07, 2018 at 02:17:12PM -0800, York Sun wrote:
>>>> Commit 8a3a7e2270b3 ("env: Pass additional parameters to the env
>>>> lookup function") dropped the default action if driver doesn't have
>>>> get_char() defined. This causes failure to get environmental
>>>> variables from NOR flash. Add back this default action for now.
>>>>
>>>> Signed-off-by: York Sun <york.sun at nxp.com>
>>>> CC: Maxime Ripard <maxime.ripard at free-electrons.com>
>>>> ---
>>>> Limited test on LS1043ARDB.
>>>>
>>>>    env/env.c | 2 +-
>>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/env/env.c b/env/env.c
>>>> index edfb575..210bae2 100644
>>>> --- a/env/env.c
>>>> +++ b/env/env.c
>>>> @@ -159,7 +159,7 @@ int env_get_char(int index)
>>>>    		int ret;
>>>>    		if (!drv->get_char)
>>>> -			continue;
>>>> +			return *(uchar *)(gd->env_addr + index);
>>> Thinking more about this, I think this would break the case where the
>>> first environment in your list has no get_char method, but the second
>>> might.
>>
>> How can we decide which way is wanted? With your patch below, we might end
>> up loading chars from a low-prio environment (which is not CRC checked) in
>> the early boot stage. Later, we load the environment from another env driver
>> with higher priority.
> Ah, right.
>
>> That's why I suggested removing the 'get_char' callback from the env drivers
>> :-) Early boot stage environment lookups would still work the old way
>> reading from 'gd->env_addr + index'.
> If that works on York's board, I'm all in.
>
> Maxime
>