linux-kernel - Re: [PATCH] ARM: dts: imx6sx-sdb: Remove cpufreq OPP override

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20170504125052.GP18578@dragon>
Date:   Thu, 4 May 2017 20:50:53 +0800
From:   Shawn Guo <shawnguo@...nel.org>
To:     Leonard Crestez <leonard.crestez@....com>
Cc:     Sascha Hauer <kernel@...gutronix.de>,
        Fabio Estevam <fabio.estevam@....com>,
        Anson Huang <Anson.Huang@....com>,
        Peter Chen <Peter.Chen@....com>,
        linux-arm-kernel@...ts.infradead.org, linux-pm@...r.kernel.org,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Viresh Kumar <viresh.kumar@...aro.org>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] ARM: dts: imx6sx-sdb: Remove cpufreq OPP override

On Tue, Apr 25, 2017 at 07:57:59PM +0300, Leonard Crestez wrote:
> The board file for imx6sx-dbg overrides cpufreq operating points to use

s/imx6sx-dbg/imx6sx-sdb

> higher voltages. This is done because the board has a shared rail for
> VDD_ARM_IN and VDD_SOC_IN and when using LDO bypass the shared voltage
> needs to be a value suitable for both ARM and SOC.
> 
> This was introduced in:
> 
> commit 54183bd7f766 ("ARM: imx6sx-sdb: add revb board and make it default")
> 
> This only only applies to LDO bypass mode, a feature not present in

s/only only/only

> upstream. When LDOs are enabled the effect is to use higher voltages than
> necesarry for no good reason.
> 
> Setting these higher voltages can make some boards fail to boot with ugly

Please make it clear it's RevC board.

> semi-random crashes, reminiscent of memory corruption. These failures
> happen the first time the lowest idle state is used. Remove the OPP
> override in order to fix those crashes.
> 
> Signed-off-by: Leonard Crestez <leonard.crestez@....com>

Please add tags for Fixes and Cc stable.

Shawn