Re: [PATCH v1] arm64: defconfig: Enable i.MX95 configs for booting and Ethernet

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 23/10/2025 22:05, Marek Vasut wrote:
> On 10/23/25 6:01 PM, Krzysztof Kozlowski wrote:
>> On 23/10/2025 17:53, Marek Vasut wrote:
>>> On 10/23/25 5:32 PM, Krzysztof Kozlowski wrote:
>>>> On 23/10/2025 17:27, Marek Vasut wrote:
>>>>> On 10/23/25 5:22 PM, Krzysztof Kozlowski wrote:
>>>>>> On 23/10/2025 16:03, Alexander Stein wrote:
>>>>>>> Hi,
>>>>>>>
>>>>>>> Am Donnerstag, 23. Oktober 2025, 14:19:15 CEST schrieb João Paulo Gonçalves:
>>>>>>>> From: João Paulo Gonçalves <joao.goncalves@toradex.com>
>>>>>>>>
>>>>>>>> Enable the necessary missing configs for the i.MX95 to boot and also
>>>>>>>> have Ethernet working:
>>>>>>>>
>>>>>>>> * CONFIG_NXP_ENETC4 for the network controller driver
>>>>>>>> * CONFIG_NXP_NETC_BLK_CTRL for the NETC hardware domain controller
>>>>>>>> * CONFIG_PINCTRL_IMX_SCMI for the pinctrl driver
>>>>>>>> * CONFIG_CLK_IMX95_BLK_CTL for the shared hardware domain controller
>>>>>>>>
>>>>>>>> Signed-off-by: João Paulo Gonçalves <joao.goncalves@toradex.com>
>>>>>>>> ---
>>>>>>>>     arch/arm64/configs/defconfig | 4 ++++
>>>>>>>>     1 file changed, 4 insertions(+)
>>>>>>>>
>>>>>>>> diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
>>>>>>>> index e3a2d37bd10423b028f59dc40d6e8ee1c610d6b8..787d3ae3f5afeac486a905e0943e7b0e1dcee3a9 100644
>>>>>>>> --- a/arch/arm64/configs/defconfig
>>>>>>>> +++ b/arch/arm64/configs/defconfig
>>>>>>>> @@ -354,8 +354,10 @@ CONFIG_FSL_FMAN=y
>>>>>>>>     CONFIG_FSL_DPAA_ETH=y
>>>>>>>>     CONFIG_FSL_DPAA2_ETH=y
>>>>>>>>     CONFIG_FSL_ENETC=y
>>>>>>>> +CONFIG_NXP_ENETC4=m
>>>>>>>>     CONFIG_FSL_ENETC_VF=y
>>>>>>>>     CONFIG_FSL_ENETC_QOS=y
>>>>>>>> +CONFIG_NXP_NETC_BLK_CTRL=m
>>>>>>>
>>>>>>> Are you sure this should be module? Shouldn't NFS boot be supported by
>>>>>>> default? I might be wring here though.
>>>>>>
>>>>>>
>>>>>> NFS root is supported already with this being module. Yes, it must be a
>>>>>> module, cannot be built in.
>>>>> It seems I am using it as built-in on MX95 Verdin (patch is posted on
>>>>> the ML), and yes, I do boot from NFS root without any initrd/initramfs.
>>>>> It has to be built-in for that use case to work.
>>>>
>>>>
>>>> Every arm64 platform is supposed to use initramfs and we already use all
>>>> over the place.
>>>
>>> Shouldn't the platform also be at least bootable with the defconfig ? If
>>> yes, then initramfs is a mandatory requirement for a NFS root boot (not
>>> a ... supposed to ... optional one), which does not seem to be the case
>>> until now.
>>
>> It always was a requirement, nothing new here.
> 
> Is this requirement documented anywhere then ?


Dunno, just dozen of emails.

> 
>>> I would argue the ethernet MAC support should be built-in to achieve
>>> maximum utility with the defconfig.
>>
>> No, you missed my earlier point - all decent platforms already use
>> initramfs since it is really not complicated.
> 
> Is my understanding correct, that the in-kernel defconfig is not meant 
> for practical use and is meant mainly for build-testing/build-coverage ?


It is 100% practical use - we all test our boards on defconfig. It is
not build testing, but actual runtime usage and testing. And as
mentioned many times - being able to only toggle KASAN for defconfig and
still fit in boot partition size is pretty useful.


Best regards,
Krzysztof