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

[Marek Vasut <marek.vasut@mailbox.org>]

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 ?

>> 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 ?