[PATCH 2/2] powerpc/pseries: Set CPU_FTR_DBELL according to ibm,pi-features

[Vaibhav Jain]

Nicholas Piggin <npiggin at gmail.com> writes:

> PAPR will define a new ibm,pi-features bit which says that doorbells
> should not be used even on architectures where they exist. This could be
> because they are emulated and slower than using the interrupt controller
> directly for IPIs.
>
> Wire this bit into the pi-features parser to clear CPU_FTR_DBELL, and
> ensure CPU_FTR_DBELL is not in CPU_FTRS_ALWAYS.
>
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> ---

Tested this patch on a PP64-LE lpar with the patch[1] and seeing the
relevant pi-feature bit CPU_FTR_DBELL in `cur_cpu_spec->cpu_features`
getting cleared.


[1]
https://lore.kernel.org/all/20240207035220.339726-1-npiggin@gmail.com

Hence,
Tested-by: Vaibhav Jain <vaibhav at linux.ibm.com>

-- 
Cheers
~ Vaibhav