Re: [PATCH V2 13/14] LoongArch: Adjust default config files for 32BIT/64BIT

["Arnd Bergmann" <arnd@arndb.de>]

On Wed, Nov 19, 2025, at 09:01, Huacai Chen wrote:
> On Tue, Nov 18, 2025 at 9:46 PM Arnd Bergmann <arnd@arndb.de> wrote:
>>
>> On Tue, Nov 18, 2025, at 12:27, Huacai Chen wrote:
>> > Add loongson32_defconfig (for 32BIT) and rename loongson3_defconfig to
>> > loongson64_defconfig (for 64BIT).
>> >
>> > Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
>> > Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
>> > ---
>> >  arch/loongarch/configs/loongson32_defconfig   | 1110 +++++++++++++++++
>> >  ...ongson3_defconfig => loongson64_defconfig} |    0
>>
>> I would suggest using .config fragment here and only listing
>> the differences in the defconfig files in there, rather than
>> duplicating everything.
>>
>> > +CONFIG_DMI=y
>> > +CONFIG_EFI=y
>> > +CONFIG_SUSPEND=y
>> > +CONFIG_HIBERNATION=y
>> > +CONFIG_ACPI=y
>> > +CONFIG_ACPI_SPCR_TABLE=y
>> > +CONFIG_ACPI_TAD=y
>> > +CONFIG_ACPI_DOCK=y
>> > +CONFIG_ACPI_IPMI=m
>> > +CONFIG_ACPI_HOTPLUG_CPU=y
>> > +CONFIG_ACPI_PCI_SLOT=y
>> > +CONFIG_ACPI_HOTPLUG_MEMORY=y
>> > +CONFIG_ACPI_BGRT=y
>>
>> You mention that loongarch32 uses ftb based boot,
>> so ACPI should probably be disabled here.
> I have tried my best, adding #ifdef CONFIG_ACPI all over the world but
> still failed. :)
>
> LoongArch is deeply coupled with ACPI and can hardly disabled. On the
> other hand, it is not forbidden to use ACPI for LoongArch32. So let's
> keep it, and I will modify the description for LoongArch32 booting.

Ok. You will probably want get back to it eventually, since the
32-bit port is likely intended for small-memory devices, and the
ACPI code is fairly large.

>> I would suggest turning off CONFIG_FB here (also on loongarch64).
>> There is a replacement driver for FB_EFI in DRM now.
> Do you mean simpledrm? It probably works but not always works. From
> sysfb_init() we know it only mark EFIFB as a simpledrm device when
> "compatible", so we still need FB_EFI as a fallback.

I meant CONFIG_DRM_EFIDRM, which was added earlier this year.
EFIDRM should work more reliably than SIMPLEDRM.

     Arnd