From: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
To: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Aleksandar Rikalo <arikalo@gmail.com>,
Chao-ying Fu <cfu@wavecomp.com>,
Geert Uytterhoeven <geert@linux-m68k.org>,
Greg Ungerer <gerg@kernel.org>, Hauke Mehrtens <hauke@hauke-m.de>,
Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>,
Jiaxun Yang <jiaxun.yang@flygoat.com>,
linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org,
Marc Zyngier <maz@kernel.org>,
Paul Burton <paulburton@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Serge Semin <fancer.lancer@gmail.com>,
Thomas Gleixner <tglx@linutronix.de>,
Tiezhu Yang <yangtiezhu@loongson.cn>,
Gregory CLEMENT <gregory.clement@bootlin.com>
Subject: Re: [PATCH v7 05/12] clocksource: mips-gic-timer: Always use cluster 0 counter as clocksource
Date: Mon, 28 Oct 2024 16:15:57 +0100 [thread overview]
Message-ID: <Zx+qrRVdv5EGXbCF@alpha.franken.de> (raw)
In-Reply-To: <3c98775b-b61b-478f-838e-59f8e1cf8aed@linaro.org>
On Mon, Oct 28, 2024 at 03:54:48PM +0100, Daniel Lezcano wrote:
> On 19/10/2024 09:10, Aleksandar Rikalo wrote:
> > From: Paul Burton <paulburton@kernel.org>
> >
> > 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@kernel.org>
> > Signed-off-by: Chao-ying Fu <cfu@wavecomp.com>
> > Signed-off-by: Dragan Mladjenovic <dragan.mladjenovic@syrmia.com>
> > Signed-off-by: Aleksandar Rikalo <arikalo@gmail.com>
> > Tested-by: Serge Semin <fancer.lancer@gmail.com>
> > ---
>
> May I take this patch through the clocksource tree ?
sure, should be the best option.
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]
next prev parent reply other threads:[~2024-10-28 15:17 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-10-19 7:10 [PATCH v7 00/12] MIPS: Support I6500 multi-cluster configuration Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 01/12] irqchip/mips-gic: Introduce for_each_online_cpu_gic() Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 02/12] irqchip/mips-gic: Support multi-cluster in for_each_online_cpu_gic() Aleksandar Rikalo
2024-10-25 22:17 ` Thomas Gleixner
2024-10-19 7:10 ` [PATCH v7 03/12] irqchip/mips-gic: Setup defaults in each cluster Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 04/12] irqchip/mips-gic: Multi-cluster support Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 05/12] clocksource: mips-gic-timer: Always use cluster 0 counter as clocksource Aleksandar Rikalo
2024-10-28 14:54 ` Daniel Lezcano
2024-10-28 15:15 ` Thomas Bogendoerfer [this message]
2024-10-28 15:22 ` Daniel Lezcano
2024-10-28 15:47 ` Thomas Bogendoerfer
2024-10-28 16:09 ` Daniel Lezcano
2024-10-19 7:10 ` [PATCH v7 06/12] clocksource: mips-gic-timer: Enable counter when CPUs start Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 07/12] MIPS: pm-cps: Use per-CPU variables as per-CPU, not per-core Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 08/12] MIPS: CPS: Introduce struct cluster_boot_config Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 09/12] MIPS: CPS: Boot CPUs in secondary clusters Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 10/12] dt-bindings: mips: cpu: Add property for broken HCI information Aleksandar Rikalo
2024-10-21 6:10 ` Krzysztof Kozlowski
2024-10-19 7:10 ` [PATCH v7 11/12] MIPS: CPS: Support broken HCI for multicluster Aleksandar Rikalo
2024-10-19 7:10 ` [PATCH v7 12/12] MIPS: mobileye: dts: eyeq6h: Enable cluster support Aleksandar Rikalo
2024-10-25 15:07 ` [PATCH v7 00/12] MIPS: Support I6500 multi-cluster configuration Gregory CLEMENT
2024-10-25 15:58 ` Gregory CLEMENT
[not found] ` <CAGQJe6pywUi8dnhxFopkMfP2U1PceHjTPX-CysT0bajSk_AKKg@mail.gmail.com>
2024-10-28 13:39 ` Gregory CLEMENT
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