Re: (EXT) [PATCH] arm64: dts: imx8mm: Add SNVS LPGPR on Data Modul i.MX8M Mini eDM SBC

Marek Vasut
2022-05-23T12:30:45Z

On 5/23/22 13:43, Alexander Stein wrote:
> Am Montag, 23. Mai 2022, 13:18:01 CEST schrieb Marek Vasut:
>> On 5/23/22 13:08, Alexander Stein wrote:
>>
>> Hi,
>>
>> [...]
>>
>>>> +&snvs {
>>>> + snvs-lpgpr {
>>>> + compatible = "fsl,imx8mm-snvs-lpgpr", "fsl,imx7d-snvs-
>>>
>>> lpgpr";
>>>
>>>> + };
>>>> +};
>>>> +
>>>>
>>>> &uart1 {
>>>>
>>>> pinctrl-names = "default";
>>>> pinctrl-0 = <&pinctrl_uart1>;
>>>
>>> Shouldn't this go into imx8mm.dtsi?
>>
>> No, not everyone uses this register for boot counter or wants to expose
>> it to Linux that way. This is board-specific behavior.
>
> Sure the actual usage of the general purpose registers is very much board-
> specific. Nevertheless the DT describes the hardware and there is snvs-lpgpr
> in all imx8mm. IMHO there is no harm exposing those GPR unconditionally.

Imagine someone is storing information which shouldn't be exposed to
Linux in those registers, in any way.

I see (in git grep) other SoCs already did add it unconditionally into
their DTSI though, hummmmm. Then maybe we should be consistent and just
add it to them all.