From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: Mark Rutland <mark.rutland@arm.com>
Cc: catalin.marinas@arm.com, dingtianhong@huawei.com,
will.deacon@arm.com, linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, tglx@linutronix.de
Subject: Re: [PATCH 5/7] arm64: arch_timer: work around Hisilicon erratum 161010101
Date: Thu, 2 Feb 2017 20:21:13 +0100 [thread overview]
Message-ID: <20170202192113.GA2138@mai> (raw)
In-Reply-To: <1485865196-12742-6-git-send-email-mark.rutland@arm.com>
On Tue, Jan 31, 2017 at 12:19:54PM +0000, Mark Rutland wrote:
> From: Ding Tianhong <dingtianhong@huawei.com>
>
> Erratum Hisilicon-161010101 says that the ARM generic timer counter "has
> the potential to contain an erroneous value when the timer value
> changes". Accesses to TVAL (both read and write) are also affected due
> to the implicit counter read. Accesses to CVAL are not affected.
>
> The workaround is to reread the system count registers until the value
> of the second read is larger than the first one by less than 32, the
> system counter can be guaranteed not to return wrong value twice by
> back-to-back read and the error value is always larger than the correct
> one by 32. Writes to TVAL are replaced with an equivalent write to CVAL.
>
> Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
> [Mark: split patch, fix Kconfig, reword commit message]
> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
> ---
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
next prev parent reply other threads:[~2017-02-02 19:21 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-31 12:19 [PATCH 0/7] arm64: arch_timer: work around Hisilicon erratum 161010101 Mark Rutland
2017-01-31 12:19 ` [PATCH 1/7] arm64: docs: widen silicon-errata kconfig column Mark Rutland
2017-01-31 12:19 ` [PATCH 2/7] arm64: arch_timer: add dt binding for hisilicon-161010101 erratum Mark Rutland
2017-01-31 12:19 ` [PATCH 3/7] arm64: arm_arch_timer: remove fsl-a008585 parameter Mark Rutland
2017-02-01 10:08 ` Daniel Lezcano
2017-01-31 12:19 ` [PATCH 4/7] arm64: arch_timer: introduce generic errata handling infrastructure Mark Rutland
2017-02-01 10:14 ` Daniel Lezcano
2017-02-01 10:14 ` Daniel Lezcano
2017-01-31 12:19 ` [PATCH 5/7] arm64: arch_timer: work around Hisilicon erratum 161010101 Mark Rutland
2017-02-02 18:39 ` Mark Rutland
2017-02-02 19:21 ` Daniel Lezcano [this message]
2017-01-31 12:19 ` [PATCH 6/7] arm64: arch_timer: document " Mark Rutland
2017-01-31 14:29 ` Will Deacon
2017-01-31 12:19 ` [PATCH 7/7] arm64: arch timer: Add timer erratum property for Hip05-d02 and Hip06-d03 Mark Rutland
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20170202192113.GA2138@mai \
--to=daniel.lezcano@linaro.org \
--cc=catalin.marinas@arm.com \
--cc=dingtianhong@huawei.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=tglx@linutronix.de \
--cc=will.deacon@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).