On 26.10.2021 17:12, Roger Pau Monne wrote:
> Always allow the HPET to be setup, but don't report a frequency back
> to the platform time source probe in order to avoid it from being
> selected as a valid timer if it's not usable.
>
> Doing the setup even when not intended to be used as a platform timer
> is required so that is can be used in legacy replacement mode in order
> to assert the IO-APIC is capable of receiving interrupts.
>
> Fixes: c12731493a ('x86/hpet: Use another crystalball to evaluate HPET
> usability')
I realize this has gone in already, but imo pointing at this commit is
only part of the truth (maybe the larger one). e1de4c196a2e ("x86/timer:
Fix boot on Intel systems using ITSSPRC static PIT clock gating") post-
dates d5294a302c84 ("x86: avoid HPET use on certain Intel platforms")
by over a year, yet it's that patch'es logic which the referenced
commit merely extended. I am of the opinion that e1de4c196a2e should
have made the adjustment you make now, and hence should (also) have
been tagged.
Jan
