Re: [PATCH] arm64: defconfig: Enable PINCTRL_S32G2

[Khristine Andreea Barbulescu <khristineandreea.barbulescu@oss.nxp.com>]

On 11/2/2026 4:55 PM, Krzysztof Kozlowski wrote:
> On 02/11/2026 15:49, Khristine Andreea Barbulescu wrote:
>> On 11/2/2026 4:24 PM, Greg Kroah-Hartman wrote:
>>> On Mon, Nov 02, 2026 at 03:16:35PM +0100, Khristine Andreea Barbulescu wrote:
>>>> Enable the NXP S32G2 pin controller driver in the arm64 defconfig so it
>>>> no longer requires a manual "make menuconfig" step. The symbol selects
>>>> PINCTRL_S32CC, pulling in the common S32 pin controller support used
>>>> across the S32G family.
> 
> Well, my standard request - why would we want it? You need to list the
> upstream board(s) needing it. We do not develop defconfig for downstream.
> 
> 

Hello Krzysztof,

The upstream boards needing it are the S32G2-based S32G274A-EVB and
S32G274A-RDB2 and the S32G3-based S32G399A-RDB3. All of them rely on
the SIUL2 pin controller, so a defconfig kernel needs it enabled to boot
to rootfs on these boards.

> Also, odd CC-list, really random.
> 
> Please use scripts/get_maintainers.pl to get a list of necessary people
> and lists to CC (and consider --no-git-fallback argument, so you will
> not CC people just because they made one commit years ago). It might
> happen, that command when run on an older kernel, gives you outdated
> entries. Therefore please be sure you base your patches on recent Linux
> kernel.
> 
> Tools like b4 or scripts/get_maintainer.pl provide you proper list of
> people, so fix your workflow. Tools might also fail if you work on some
> ancient tree (don't, instead use mainline) or work on fork of kernel
> (don't, instead use mainline). Just use b4 and everything should be
> fine, although remember about `b4 prep --auto-to-cc` if you added new
> patches to the patchset.
> 

You're right, generated the list on an outdated tree. Thank you for
the explanations. I'll use latest b4 / get_maintainer.pl for the next
version.

>>>>
>>>> Signed-off-by: Khristine Andreea Barbulescu <khristineandreea.barbulescu@oss.nxp.com>
>>>> ---
>>>>  arch/arm64/configs/defconfig | 1 +
>>>>  1 file changed, 1 insertion(+)
>>>>
>>>> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
>>>> index 7b4985b29b21..545a2b7db8a5 100644
>>>> --- a/arch/arm64/configs/defconfig
>>>> +++ b/arch/arm64/configs/defconfig
>>>> @@ -704,6 +704,7 @@ CONFIG_PINCTRL_BCM2712=y
>>>>  CONFIG_PINCTRL_SKY1=y
>>>>  CONFIG_PINCTRL_IMX_SCMI=y
>>>>  CONFIG_PINCTRL_IMX91=y
>>>> +CONFIG_PINCTRL_S32G2=y
>>>
>>> Why?  Shouldn't the normal platform-specific defconfig work for this
>>> instead?  what defines the arm64 defconfig to require this now for all
>>> arm74 platforms?
>>>
>>> thanks,
>>>
>>> greg k-h
>>
>> Hello Greg,
>>
>> ARCH_S32 is already enabled in the arm64 defconfig, but the supported
>> S32G boards also depend on this pin controller for their pin muxing.
>> Without it, some peripherals never finish probing, so a defconfig kernel
>> cannot boot to rootfs on these boards.
> 
> Greg has valid point, you did not really address it. Explain why it
> should be user-selectable choice in the first place.
> 
> 
> Best regards,
> Krzysztof

Agree, since the driver is required by all S32G boards, it shouldn't need
to be selected manually. In v2 I'll make PINCTRL_S32G2 default to ARCH_S32
in Kconfig, instead of adding it to the defconfig, and also list the upstream
boards needing it in the commit message.

Best regards,
Khristine