Re: [PATCH v2 2/9] dt-bindings: riscv: microchip: document the aries m100pfsevp

[<Conor.Dooley@microchip.com>]

On 30/08/2022 17:55, Krzysztof Kozlowski wrote:
> On 30/08/2022 18:25, Conor.Dooley@microchip.com wrote:
>> On 30/08/2022 15:37, Krzysztof Kozlowski wrote:
>>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>>
>>> On 30/08/2022 13:17, Conor Dooley wrote:
>>>> Add compatibles for both configurations of the Aries Embedded
>>>> M100PFSEVP SOM + EVK platform.
>>>>
>>>> Link: https://www.aries-embedded.com/polarfire-soc-fpga-microsemi-m100pfs-som-mpfs025t-pcie-serdes
>>>> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
>>>> ---
>>>>  Documentation/devicetree/bindings/riscv/microchip.yaml | 3 +++
>>>>  1 file changed, 3 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/riscv/microchip.yaml b/Documentation/devicetree/bindings/riscv/microchip.yaml
>>>> index 485981fbfb4b..04ebd48caaa7 100644
>>>> --- a/Documentation/devicetree/bindings/riscv/microchip.yaml
>>>> +++ b/Documentation/devicetree/bindings/riscv/microchip.yaml
>>>> @@ -27,9 +27,12 @@ properties:
>>>>
>>>>        - items:
>>>>            - enum:
>>>> +              - aries,m100pfsevp-emmc
>>>> +              - aries,m100pfsevp-sdcard
>>>
>>> Usually sd card is pluggable, so what is the actual difference here? For
>>> example this one:
>>> https://shop.aries-embedded.de/evaluation-kit/m/m100pfsevp/445/m100pfsevp-250baab
>>> has eMMC and SD card...
>>
>> Yeah, both are there but it is muxed by the bootloader using a GPIO. For
>> icicle this is done by a mux in the FPGA fabric instead. T
> 
> Ah, this is still just one MMC controller - either as eMMC or as SD-card?

Yes.

> 
>> w dts were
>> needed so that the gpio-hog could be set correctly. Out of curiosity, I can
>> have the same compatible in multiple devicetrees right? In that case, it
>> would just be "aries,m100pfsevp" here and I could put that in both?
>> Would make things easier..
> 
> Depends, but I would say for this case rather not. The compatible should
> identify the board. If the boards are different, one compatible should
> not identify both of them. Imagine U-Boot (or something else) trying to
> match the DTS.

It is the same board though, the way the bootloader works is that if it
detects an SD-card it will use that to boot from, and if not will fall back
to the emmc.