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

[Huacai Chen]

On Wed, Nov 19, 2025 at 4:13 PM Arnd Bergmann <arnd@xxxxxxxx> wrote:
>
> On Wed, Nov 19, 2025, at 09:01, Huacai Chen wrote:
> > On Tue, Nov 18, 2025 at 9:46 PM Arnd Bergmann <arnd@xxxxxxxx> 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@xxxxxxxxxxx>
> >> > Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
> >> > ---
> >> >  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.
OK, I will disable FB_EFI and enable EFIDRM instead.

Huacai

>
>      Arnd
>