[U-Boot] [PATCH v2 2/2] Tegra: MMC: Add DT support to MMC driver for all T20 boards

[Stephen Warren <swarren@wwwdotorg.org>]

On 02/13/2013 12:59 PM, Tom Warren wrote:
> Stephen,
> 
> On Tue, Feb 12, 2013 at 2:06 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
>> On 02/12/2013 01:57 PM, Tom Warren wrote:
>>> Stephen,
>>>
>>> On Tue, Feb 12, 2013 at 1:38 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
>>>> On 02/11/2013 10:17 AM, Tom Warren wrote:
>>>>> tegra_mmc_init() now parses the DT info for bus width, WP/CD GPIOs, etc.
>>>>> Tested on Seaboard, fully functional.
>>>>>
>>>>> Tamonten boards (medcom-wide, plutux, and tec) use a different/new
>>>>> dtsi file w/common settings.
>>
>>>>> diff --git a/include/configs/medcom-wide.h b/include/configs/medcom-wide.h
>>>>> diff --git a/include/configs/plutux.h b/include/configs/plutux.h
>>>>> diff --git a/include/configs/tec.h b/include/configs/tec.h
>>>>
>>>> In all 3 of those files ...
>>>>
>>>>>  #define CONFIG_DEFAULT_DEVICE_TREE   tegra20-medcom-wide
>>>>
>>>> Why not change that define ...
>>>>
>>>>>  #define CONFIG_OF_CONTROL
>>>>>  #define CONFIG_OF_SEPARATE
>>>>> +#undef CONFIG_ARCH_DEVICE_TREE
>>>>> +#define CONFIG_ARCH_DEVICE_TREE              tegra20-tamonten
>>>>
>>>> rather than adding that one? All the other Tegra boards only set
>>>> CONFIG_DEFAULT_DEVICE_TREE.
>>>
>>> CONFIG_DEFAULT_DEVICE_TREE is the .dts file (board/nvidia/dts).
>>> CONFIG_ARCH_DEVICE_TREE is the .dtsi file (arch/arm/dts). See
>>> Thierry's explanation, also.
>>
>> So why set CONFIG_ARCH_DEVICE_TREE to tegra20-tamonten here; if that
>> variable is supposed to point at the SoC .dtsi file, that value is
>> wrong; it *should* be tegra20.dtsi.
>>
>> Oh yuck. I see what's going on now. e.g. tegra20-medcom-wide.dts is
>> including ARCH_CPU_DTS. It should be including tegra20-tamonten.dtsi,
>> which then includes ARCH_CPU_DTS. The ARCH_CPU_DTS variable is supposed
>> to only ever point at the SoC .dtsi file, not any "intermediate" .dtsi
>> file... You probably need to put tegra20-tamonten.dtsi into
>> board/avionic-design/dts rather than arch/arm/dts to make that work.
> 
> OK, I've removed the overrides for CONFIG_ARCH_DEVICE_TREE in the AD
> config files, and added 'tegra20-tamonten.dtsi' to the include line in
> the AD .dts files.

Great.

> I have to add an include path to the DTC command
> line in dts/Makefile so it can find tegra20-tamonten.dtsi in
> arch/$(ARCH)/dts, but it all builds fine.

If you move tegra20-tamonten.dtsi to boards/avionic-design/dts, do you
still need an include path? Since that file is board-/vendor-specific,
it really shouldn't be in arch/arm/dts if that directory typically only
contains SoC .dtsi files.