Re: [PATCH 1/6] MIPS: Ingenic: Fix inverted MIPS_NO_APPENDED_DTB logic in Kconfig

[Paul Cercueil]

Hi Nikolaus,

Le dimanche 25 octobre 2026 à 20:20 +0100, H. Nikolaus Schaller a
écrit :
> Correct the inverted conditional selection of BUILTIN_DTB for
> MACH_INGENIC.
> 
> Currently, the Kconfig logic forcefully selects BUILTIN_DTB when
> MIPS_NO_APPENDED_DTB is enabled (i.e., when no DTB should be appended
> to the image). This unintended behavior prevents turning off the
> built-in DTB fallback, which is required when the kernel should use
> a DTB provided directly by the bootloader.
> 
> Fix this by reversing the polarity using the logical NOT operator.
> 
> Fixes: f0f4a753079c ("MIPS: generic: Add support for Ingenic SoCs")
> Fixes: 15205fc05482 ("MIPS: ingenic: Add support for appended
> devicetree")
> Signed-off-by: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx>

The original code is not an 'unintended behaviour', it works as it was
designed to work: if the kernel is not configured for an appended DTB,
then a DTB should be built-in. This is because on Ingenic SoCs at
least, at the time this code was written no bootloader was passing the
DTB to the kernel.

I understand your usecase (which is very reasonnable) but this fix as-
is only fixes things for you, while breaking every other board.

I'd suggest to fix it by adding a proper description to BUILTIN_DTB (so
that it can be selected from the UI or a defconfig), then update all
arch/mips/configs/ for Ingenic based boards to enable
CONFIG_BUILTIN_DTB=y unless they rely on the appended DTB
functionality. Then this "select BUILTIN_DTB if MIPS_NO_APPENDED_DTB"
Kconfig dependency can be retired.

Cheers,
-Paul