Re: [PATCH v4 07/14] clocksource: mips-gic-timer: Always use cluster 0 counter as clocksource

[Daniel Lezcano]

On 11/05/2024 12:43, Aleksandar Rikalo wrote:
> From: Paul Burton <paulburton@xxxxxxxxxx>
>
> In a multi-cluster MIPS system we have multiple GICs - one in each
> cluster - each of which has its own independent counter. The counters in
> each GIC are not synchronised in any way, so they can drift relative to
> one another through the lifetime of the system. This is problematic for
> a clocksource which ought to be global.
>
> Avoid problems by always accessing cluster 0's counter, using
> cross-cluster register access. This adds overhead so we only do so on
> systems where we actually have CPUs present in multiple clusters.
> For now, be extra conservative and don't use gic counter for vdso or
> sched_clock in this case.
>
> Signed-off-by: Paul Burton <paulburton@xxxxxxxxxx>
> Signed-off-by: Chao-ying Fu <cfu@xxxxxxxxxxxx>
> Signed-off-by: Dragan Mladjenovic <dragan.mladjenovic@xxxxxxxxxx>
> Signed-off-by: Aleksandar Rikalo <aleksandar.rikalo@xxxxxxxxxx>
> ---

Applied patch 7 and 8

Thanks

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