Re: [PATCH v7 05/12] clocksource: mips-gic-timer: Always use cluster 0 counter as clocksource
From: Daniel Lezcano
Date: Mon Oct 28 2024 - 10:55:05 EST
On 19/10/2024 09:10, Aleksandar Rikalo wrote:
From: Paul Burton <paulburton@xxxxxxxxxx>
In a multi-cluster MIPS system, there are multiple GICs - one in each
cluster - each of which has its independent counter. The counters in
each GIC are not synchronized in any way, so they can drift relative
to one another through the lifetime of the system. This is problematic
for a clock source which ought to be global.
Avoid problems by always accessing cluster 0's counter, using
cross-cluster register access. This adds overhead so it is applied only
on multi-cluster systems.
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 <arikalo@xxxxxxxxx>
Tested-by: Serge Semin <fancer.lancer@xxxxxxxxx>
---
May I take this patch through the clocksource tree ?
--
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog