linux-kernel - Re: [PATCH 00/14] arm64: dts: imx8mp: correct pad settings

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: <42f2ba58-acd9-a214-83f2-037f669d8d59@prevas.dk>
Date:   Wed, 22 Jun 2022 08:31:48 +0200
From:   Rasmus Villemoes <rasmus.villemoes@...vas.dk>
To:     "Peng Fan (OSS)" <peng.fan@....nxp.com>, robh+dt@...nel.org,
        krzysztof.kozlowski+dt@...aro.org, shawnguo@...nel.org,
        s.hauer@...gutronix.de
Cc:     festevam@...il.com, linux-imx@....com, hvilleneuve@...onoff.com,
        l.stach@...gutronix.de, abbaraju.manojsai@...rulasolutions.com,
        jagan@...rulasolutions.com, matteo.lisi@...icam.com,
        tharvey@...eworks.com, t.remmet@...tec.de,
        u.kleine-koenig@...gutronix.de, t.remmet@...tec.deh,
        devicetree@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org, Peng Fan <peng.fan@....com>
Subject: Re: [PATCH 00/14] arm64: dts: imx8mp: correct pad settings

On 22/06/2022 08.13, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@....com>
> 
> i.MX8MP iomux pad BIT3 and BIT0 are reserved bits. Writing 1 to the
> reserved bit will be ignored and reading will still return 0. Although
> function not broken with reserved bits set, we should not set reserved
> bits.

Thank you, these have really been bugging my while trying to bring up an
imx8mp-based board and adding the right pinmux settings - not knowing
whether there was some undocumented effect from including one of those
bits has led me astray more than once.

One question: E.g. in patch 11, you change the setting from 0x49 to
0x40, which is of course exactly what the patch description says. But
when bit 8 (PE) is not set, is there any effect from either setting of
bit 6 (PUE)? Not that I suggest changing to 0x00, but I'm just curious.

For the series:

Reviewed-by: Rasmus Villemoes <rasmus.villemoes@...vas.dk>