From: arnd@arndb.de (Arnd Bergmann)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 0/2] ARM: EXYNOS: Allow to use architected timer
Date: Tue, 06 Oct 2015 10:37:16 +0200 [thread overview]
Message-ID: <6613638.q5qyQZxXy7@wuerfel> (raw)
In-Reply-To: <cover.1444119342.git.p.fedin@samsung.com>
On Tuesday 06 October 2015 11:23:58 Pavel Fedin wrote:
> Exynos platform officially uses "multi-core timer" AKA MCT. However, it
> also has a possibility to access the same timer using CP15 (AKA
> architected timer) registers.
>
> In order to be able to use KVM, we need CP15 timer support. In its turn,
> MCT needs to be turned on before any accesses will work. This patchset
> allows to specify "CP15 compatibility mode" for the MCT by inserting
> armv7-timer node as a child for MCT device. In this case MCT driver will
> only enable the timer, leaving the rest for architected timer driver.
IIRC the use of the CP15 timer is not reliable on this platform.
I don't have a link ready, but this has come up a few times.
Kukjin Kim probably knows the details.
Regarding KVM usage, would it be possible to emulate the architected
timer from qemu instead?
Arnd
next prev parent reply other threads:[~2015-10-06 8:37 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-06 8:23 [PATCH 0/2] ARM: EXYNOS: Allow to use architected timer Pavel Fedin
2015-10-06 8:23 ` [PATCH 1/2] exynos_mct: Allow to use architected timer mode Pavel Fedin
2015-10-06 8:24 ` [PATCH 2/2] ARM: dts: Use architected timer on Exynos 5410 Pavel Fedin
2015-10-06 8:33 ` Chanwoo Choi
2015-10-06 8:49 ` Pavel Fedin
2015-10-06 8:37 ` Arnd Bergmann [this message]
2015-10-06 8:51 ` [PATCH 0/2] ARM: EXYNOS: Allow to use architected timer Alexey Klimov
2015-10-06 8:56 ` Pavel Fedin
2015-10-06 9:12 ` Arnd Bergmann
2015-10-06 9:44 ` Pavel Fedin
2015-10-06 10:03 ` Arnd Bergmann
2015-10-06 10:09 ` Kukjin Kim
2015-10-06 10:16 ` Pavel Fedin
2015-10-06 10:25 ` Kukjin Kim
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