Re: Keep bootloader DTB when ACPI is enabled

From: Rob Herring
Date: Fri Jan 24 2025 - 10:03:54 EST


On Tue, Jan 21, 2025 at 2:18 AM Stefan Wiehler <stefan.wiehler@xxxxxxxxx> wrote:
>
> Hi all,
>
> We store various metadata (e.g. IDs and serial numbers) in the DT which must be
> consistent over multiple product generations; therefore we enable CONFIG_OF
> even when ACPI is used for boot. On such ACPI-based (i.e. x86) boards, ACPI is
> used for boot while the DT holds only product-specific nodes not of any
> interest to the core kernel. While this is currently not an issue on our 6.1
> kernel, I noticed that commit 7b937cc243e5 ("of: Create of_root if no dtb
> provided by firmware") drops the bootloader provided DTB if ACPI is not
> disabled [1]. When one removes this check, several warnings are emitted because
> register_lapic_address() and topology_register_boot_apic() are called from both
> ACPI and DT initialization [2] [3].

I think both of these issues are fixed by this series[1]. I intend to
pick up patch 2. Patch 1 can go thru x86 tree.

Rob

[1] https://lore.kernel.org/all/20250105172741.3476758-1-dmaluka@xxxxxxxxxxxx