Re: [PATCH 2/3] riscv: Remove non-standard linux,elfcorehdr handling

From: Palmer Dabbelt
Date: Wed Jun 30 2021 - 22:55:32 EST


On Wed, 16 Jun 2021 07:47:46 PDT (-0700), robh+dt@xxxxxxxxxx wrote:
On Wed, Jun 16, 2021 at 4:43 AM Nick Kossifidis <mick@xxxxxxxxxxxx> wrote:

Στις 2021-06-16 10:56, Geert Uytterhoeven έγραψε:
>
> I can't comment on the duplication on arm64, but to me, /chosen
> sounds like the natural place for both "linux,elfcorehdr" and
> "linux,usable-memory-range". First rule of DT is "DT describes
> hardware, not software policy", with /chosen describing some software
> configuration.
>

We already have "linux,usable-memory" on /memory node:
https://elixir.bootlin.com/linux/v5.13-rc6/source/drivers/of/fdt.c#L1011
and it makes perfect sense to be there since it overrides /memory's reg
property.

Why define another binding for the same thing on /chosen ?

Go look at the thread adding "linux,usable-memory-range". There were
only 35 versions of it[1]. I wasn't happy with a 2nd way either, but
as I've mentioned before we don't always have /memory node.

I don't really understand what's going on here, but IIUC what I merged in 5.13 doesn't match the behavior that other architectures have. In that case I'm happy moving RISC-V over to the more standard way of doing things and just calling what we have in 5.13 a screwup.

Sorry for the confusion.