On Sat, Jun 5, 2021 at 8:37 AM Alex Ghiti [off-list ref] wrote:

Le 4/06/2021 à 15:08, Arnd Bergmann a écrit :

quoted

On Fri, Jun 4, 2021 at 2:06 PM Alexandre Ghiti [off-list ref] wrote:

quoted

Fix BUILTIN_DTB config which resulted in a dtb that was actually not built
into the Linux image: in the same manner as Canaan soc does, create an object
file from the dtb file that will get linked into the Linux image.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>

Along the same lines as the comment that Jisheng Zhang made on the fixed
address, building a dtb into the kernel itself fundamentally breaks generic
kernel images.

I can understand using it on K210, which is extremely limited and wouldn't
run a generic kernel anyway, but for normal platforms like microchip and
sifive, it would be better to disallow CONFIG_BUILTIN_DTB in Kconfig
and require a non-broken boot loader.

I kind of disagree because if I want to build a custom kernel for those
platforms with a builtin dtb for some reasons (debug, development..Etc),
I think I should be able to do so.

How is the builtin dtb better than appended dtb, or passing the dtb to the
boot loader in that case?

         Arnd