linux-kernel - Re: [PATCH 0/9] Panfrost: Improve and add MediaTek SoCs support

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: <CAGXv+5HkdWUWmq0Jk5F2ZuFVHN5T07CYwBdzSWR7Z0=pmkJ5Mw@mail.gmail.com>
Date:   Thu, 9 Feb 2023 17:10:15 +0800
From:   Chen-Yu Tsai <wenst@...omium.org>
To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@...labora.com>
Cc:     airlied@...il.com, tomeu.vizoso@...labora.com,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
        dri-devel@...ts.freedesktop.org, steven.price@....com,
        robh+dt@...nel.org, linux-mediatek@...ts.infradead.org,
        alyssa.rosenzweig@...labora.com, krzysztof.kozlowski+dt@...aro.org,
        matthias.bgg@...il.com, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH 0/9] Panfrost: Improve and add MediaTek SoCs support

On Wed, Feb 8, 2023 at 6:37 PM AngeloGioacchino Del Regno
<angelogioacchino.delregno@...labora.com> wrote:
>
> This series adds support for new MediaTek SoCs (MT8186/MT8192/MT8195)
> and improves MT8183 support: since the mtk-regulator-coupler driver
> was picked, it is now useless for Panfrost to look for, and manage,
> two regulators (GPU Vcore and GPU SRAM) on MediaTek;
>
> The aforementioned driver will take care of keeping the voltage
> relation (/constraints) of the two regulators on its own when a
> voltage change request is sent to the Vcore, solving the old time
> issue with not working DVFS on Panfrost+MediaTek (due to devfreq
> supporting only single regulator).
>
> In the specific case of MT8183, in order to not break the ABI, it
> was necessary to add a new compatible for enabling DVFS.

Tested on MT8183 Juniper (Kukui-based device), MT8192 Hayato (Asurada-based),
and MT8195 Tomato (Cherry-based).

GPU probed. When running glmark-es2-drm, observed state transitions in
/sys/class/devfreq/13040000.gpu/trans_stat , as well as actual changes to
values for regulators and clocks.

Tested-by: Chen-Yu Tsai <wenst@...omium.org>

Also observed that sometimes when glmark terminated, the GPU would not be
brought down to the lowest OPP.