linux-kernel - Re: [PATCH v3] drm/msm/dp: cleared DP_DOWNSPREAD

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] [day] [month] [year] [list]

Date:   Thu, 8 Sep 2022 19:07:21 +0300
From:   Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To:     Kuogee Hsieh <quic_khsieh@...cinc.com>
Cc:     robdclark@...il.com, sean@...rly.run, swboyd@...omium.org,
        dianders@...omium.org, vkoul@...nel.org, daniel@...ll.ch,
        airlied@...ux.ie, agross@...nel.org, bjorn.andersson@...aro.org,
        quic_abhinavk@...cinc.com, quic_sbillaka@...cinc.com,
        freedreno@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3] drm/msm/dp: cleared DP_DOWNSPREAD_CTRL register before
 start link training

On Thu, 8 Sept 2022 at 18:38, Kuogee Hsieh <quic_khsieh@...cinc.com> wrote:
>
> DOWNSPREAD_CTRL (0x107) shall be cleared to 0 upon power-on reset or an
> upstream device disconnect. This patch will enforce this rule by always
> cleared DOWNSPREAD_CTRL register to 0 before start link training. At rare
> case that DP MSA timing parameters may be mis-interpreted by the sink
> which causes audio sampling rate be calculated wrongly and cause audio
> did not work at sink if DOWNSPREAD_CTRL register is not cleared to 0.
> This patch also make sure bring sink out of D3 power-down mode into D0
> (normal operation mode) successfully by retrying 3 times.

Split into three separate patches please.


-- 
With best wishes
Dmitry