mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Will Deacon <will.deacon@arm.com>
To: Stephen Boyd <sboyd@codeaurora.org>
Cc: "linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	Stepan Moskovchenko <stepanm@codeaurora.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-arm-msm@vger.kernel.org" <linux-arm-msm@vger.kernel.org>
Subject: Re: [PATCHv2 3/3] ARM: Work around faulty ISAR0 register in some Krait CPUs
Date: Mon, 18 Mar 2013 18:34:36 +0000	[thread overview]
Message-ID: <20130318183435.GD31193@mudshark.cambridge.arm.com> (raw)
In-Reply-To: <1363631337-13816-4-git-send-email-sboyd@codeaurora.org>

On Mon, Mar 18, 2013 at 06:28:57PM +0000, Stephen Boyd wrote:
> From: Stepan Moskovchenko <stepanm@codeaurora.org>
> 
> Some early versions of the Krait CPU design incorrectly indicate
> that they only support the UDIV and SDIV instructions in Thumb
> mode when they actually support them in ARM and Thumb mode. It
> seems that these CPUs follow the DDI0406B ARM ARM which has two
> possible values for the divide instructions field, instead of the
> DDI0406C document which has three possible values.
> 
> Work around this problem by checking the MIDR against Krait CPUs
> with this faulty ISAR0 register and force the hwcaps to indicate
> support in both modes.
> 
> Cc: Will Deacon <will.deacon@arm.com>
> Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
> [sboyd: Rewrote commit text to reflect real reasoning now that
> 	we autodetect udiv/sdiv]
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
> ---
>  arch/arm/mm/proc-v7.S | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)

Acked-by: Will Deacon <will.deacon@arm.com>

Will

  reply	other threads:[~2013-03-18 18:34 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-18 18:28 [PATCHv2 0/3] Detect UDIV/SDIV support from ISAR0 Stephen Boyd
2013-03-18 18:28 ` [PATCHv2 1/3] ARM: Clear IDIVT hwcap if CONFIG_ARM_THUMB=n Stephen Boyd
2013-03-18 18:28 ` [PATCHv2 2/3] ARM: Detect support for SDIV/UDIV from ISAR0 register Stephen Boyd
2013-04-18  9:10   ` Uwe Kleine-König
2013-03-18 18:28 ` [PATCHv2 3/3] ARM: Work around faulty ISAR0 register in some Krait CPUs Stephen Boyd
2013-03-18 18:34   ` Will Deacon [this message]
2013-03-18 18:46     ` Stephen Boyd

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=20130318183435.GD31193@mudshark.cambridge.arm.com \
    --to=will.deacon@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=sboyd@codeaurora.org \
    --cc=stepanm@codeaurora.org \
    /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

Powered by JetHome