linux-kernel - Re: [PATCH v2] drm/meson: Fix an Alpha Primary Plane bug on Meson GXL/GXM SoCs

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:   Mon, 3 Dec 2018 11:10:57 +0100
From:   Neil Armstrong <narmstrong@...libre.com>
To:     Maxime Jourdan <mjourdan@...libre.com>
Cc:     dri-devel@...ts.freedesktop.org, linux-amlogic@...ts.infradead.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2] drm/meson: Fix an Alpha Primary Plane bug on Meson
 GXL/GXM SoCs

On 03/12/2018 10:04, Maxime Jourdan wrote:
> Hi Neil,
> On Wed, Nov 28, 2018 at 11:07 AM Neil Armstrong <narmstrong@...libre.com> wrote:
>>
>> On the Amlogic GXL & GXM SoCs, a bug occurs on the primary plane when
>> alpha is used where the alpha is not aligned with the pixel content.
>>
>> The woraround Amlogic implemented is to reset the OSD1 plane hardware
>> block each time the plane is (re)enabled, solving the issue.
>>
> 
> typo: woraround -> workaround

I'll fix when applying !

> 
>> In the reset, we still need to save the content of 2 registers which
>> depends on the status of the plane, in addition to reload the scaler
>> conversion matrix at the same time.
>>
>> Signed-off-by: Neil Armstrong <narmstrong@...libre.com>
>> ---
>> Changes since v1 at [1]:
>> - Fix flickering and shaking by moving reset when plane is disabled
>>
>> [1] https://patchwork.freedesktop.org/patch/263550/
>>
>>  drivers/gpu/drm/meson/meson_plane.c | 12 ++++++++++++
>>  drivers/gpu/drm/meson/meson_viu.c   | 27 +++++++++++++++++++++++++++
>>  drivers/gpu/drm/meson/meson_viu.h   |  1 +
>>  3 files changed, 40 insertions(+)
>>
> 
> I can confirm the fix works on GXL (aml-s905x-cc), tested with
> LibreElec, 1080p resolution.
> 
> Anything using alpha on the primary plane used to be randomly
> "shifted" with black patches, and this was particularly visible with
> subtitles.
> 
> Things seem OK now. Thanks!
> 
> Tested-by: Maxime Jourdan <mjourdan@...libre.com>
> Reviewed-by: Maxime Jourdan <mjourdan@...libre.com>
> 

Thanks,

Applied on drm-misc-next

Neil