[PATCH] Convert CONFIG_SYS_MMC_ENV_DEV et al to Kconfig

[Stefan Roese]

Hi Rasmus,

On 05.08.20 10:47, Rasmus Villemoes wrote:
> On 24/07/2020 23.14, Tom Rini wrote:
>> This converts the following to Kconfig:
>>     CONFIG_SYS_MMC_ENV_DEV
>>     CONFIG_SYS_MMC_ENV_PART
> 
> Yes, please! That's the only thing preventing us from running a vanilla
> upstream U-Boot on a number of our boards where we have the defconfig
> out of tree - we currently have a single patch touching a few config
> headers.
> 
>> Cc: Priyanka Jain <priyanka.jain at nxp.com>
>> Cc: Madalin Bucur <madalin.bucur at oss.nxp.com>
>> Signed-off-by: Tom Rini <trini at konsulko.com>
>> ---
>> Due to some non-environment usage of the variables, cc'ing a few folks.
> 
> Yes, and those are the reason I didn't already send a patch.
> 
>> diff --git a/env/Kconfig b/env/Kconfig
>> index 38e7fadbb93a..2eb2fe48da3d 100644
>> --- a/env/Kconfig
>> +++ b/env/Kconfig
>> @@ -567,6 +567,25 @@ config SYS_RELOC_GD_ENV_ADDR
>>   	  Relocate the early env_addr pointer so we know it is not inside
>>   	  the binary. Some systems need this and for the rest, it doesn't hurt.
>>   
>> +config SYS_MMC_ENV_DEV
>> +	int "mmc device number"
>> +	depends on ENV_IS_IN_MMC || ENV_IS_IN_FAT || SYS_LS_PPA_FW_IN_MMC || \
>> +		CMD_MVEBU_BUBT || FMAN_ENET || QE
> 
> Slight yuck. But I suppose that those (ab)uses of CONFIG_SYS_MMC_ENV_DEV
> can grow their own proper config symbols piecemeal and then get removed
> from that list, rather than having to wean off all of them before
> SYS_MMC_ENV_* can get converted.
> 
> Why is ENV_IS_IN_FAT in that list? That has its own already-existing
> ENV_FAT_DEVICE_AND_PART.
> 
> And a more general question: What does the SYS_ prefix mean? Some config
> symbols have it, but I can't find any pattern to it. (I don't mean it
> should be changed with this patch, but I'm curious if there is any
> tribal knowledge here that I should be aware of.)

The SYS_ prefix dates back quite some time, most likely nearly to the
beginning of U-Boot or more precise PPCBoot then. Here an extract
from the README:

* Configuration _OPTIONS_:
   These are selectable by the user and have names beginning with
   "CONFIG_".

* Configuration _SETTINGS_:
   These depend on the hardware etc. and should not be meddled with if
   you don't know what you're doing; they have names beginning with
   "CONFIG_SYS_".

Its most likely outdated by now, as this naming convention has not
been followed in the last years, AFAICT.

Thanks,
Stefan