linux-kernel - Re: [PATCH 3/8] ARM: dts: imx7s: Adjust anatop-enable-bit for 'reg

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]

Date:   Fri, 14 Apr 2017 23:32:43 +0800
From:   Dong Aisheng <dongas86@...il.com>
To:     Andrey Smirnov <andrew.smirnov@...il.com>
Cc:     Shawn Guo <shawnguo@...nel.org>, yurovsky@...il.com,
        Sascha Hauer <kernel@...gutronix.de>,
        Fabio Estevam <fabio.estevam@....com>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Russell King <linux@...linux.org.uk>,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 3/8] ARM: dts: imx7s: Adjust anatop-enable-bit for
 'reg_1p0d'

On Thu, Apr 13, 2017 at 06:32:37AM -0700, Andrey Smirnov wrote:
> In PMU_REG_1P0Dn ENABLE_LINREG is bit 0. Bit 31 is called OVERRIDE and
> it serves the function of granting permission to GPC IP block to alter
> various bit-fields of the register. The reason why this property, that
> trickeld here from Freescale BSP, is set to 31 is because in the code
> it came from it is used in conjunction with a notifier handler for
> REGULATOR_EVENT_PRE_DO_ENABLE and REGULATOR_EVENT_PRE_DO_DISABLE
> events (not found in upstream kernel) that triggers GPC to start
> manipulating aforementioned other bitfields.
> 
> Since:
> 	a) none of the aforementioned machinery is implemented by
> 	   upstream
> 	b) using 'anatop-enable-bit' in that capacity is a bit of a
> 	   semantic stretch

Yes, this does is a bit of semantic stretch.
FSL using is combined with regulator notify and that do bring a bit
of complexity.

I'm not sure if it's good to introduce another anatop-override-bit
to separate, but i'm a bit scare since there's already many....

> 
> simplify the situation by setting the value of 'anatop-enable-bit' to
> point to ENABLE_LINREG (same as i.MX6).
> 
> Cc: yurovsky@...il.com
> Cc: Sascha Hauer <kernel@...gutronix.de>
> Cc: Fabio Estevam <fabio.estevam@....com>
> Cc: Rob Herring <robh+dt@...nel.org>
> Cc: Mark Rutland <mark.rutland@....com>
> Cc: Russell King <linux@...linux.org.uk>
> Cc: devicetree@...r.kernel.org
> Cc: linux-kernel@...r.kernel.org
> Cc: linux-arm-kernel@...ts.infradead.org
> Signed-off-by: Andrey Smirnov <andrew.smirnov@...il.com>
> ---
>  arch/arm/boot/dts/imx7s.dtsi | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/boot/dts/imx7s.dtsi b/arch/arm/boot/dts/imx7s.dtsi
> index 22c9788..8fee299 100644
> --- a/arch/arm/boot/dts/imx7s.dtsi
> +++ b/arch/arm/boot/dts/imx7s.dtsi
> @@ -516,7 +516,7 @@
>  					anatop-min-bit-val = <8>;
>  					anatop-min-voltage = <800000>;
>  					anatop-max-voltage = <1200000>;
> -					anatop-enable-bit = <31>;
> +					anatop-enable-bit = <0>;

The change of this line seems already exist in patch 1.

Regards
Dong Aisheng