Re: [PATCH 2/2] clk: qcom: restrict drivers per ARM/ARM64

From: Krzysztof Kozlowski
Date: Wed Feb 01 2023 - 02:13:42 EST


On 31/01/2023 00:30, Stephen Boyd wrote:
> Quoting Krzysztof Kozlowski (2023-01-26 01:31:55)
>> On 25/01/2023 21:44, Stephen Boyd wrote:
>>> Quoting Krzysztof Kozlowski (2023-01-23 01:49:25)
>>>> There is no point to allow selecting pin-controller drivers for Qualcomm
>>>
>>> pin controllers?
>>
>> Copy-paste, I'll fix it.
>>
>>>
>>>> ARMv7 SoCs when building ARM64 kernel, and vice versa. This makes
>>>> kernel configuration more difficult as many do not remember the Qualcomm
>>>> SoCs model names/numbers. There won't be a single image for ARMv7 and
>>>> ARMv8/9 SoCs, so no features/options are lost.
>>>
>>> Are the drivers used in arm32 emulation mode on these SoCs? I recall
>>> there are some SoCs they run with the arm architecture.
>>
>> I did not add it to the few SoCs which have upstream DTS in ARM and
>> ARM64. I added only to the ones which are in one specific folder. Also
>> my patch does not affect defconfigs (qcom_defconfig and arm64/defconfig).
>
> Cool, thanks for checking. Is it possible to take a dtb from arm64 dts
> directory and boot it on an armv8 CPU running in 32-bit mode? Just
> wondering if even having the dts file exist in the arm64 architecture
> really matters here.

If DTSI (and/or board DTS) is in arm64, you still need DTS or a link in
arm directory. If such one is added, then the restrictions here can be
removed. Have in mind that I did the same already for pinctrl.


Best regards,
Krzysztof