Re: [PATCH v13 0/4] drm/panfrost: Add support for mt8183 GPU

[Ezequiel Garcia]

Hi Neil,

On Mon, 26 Apr 2021 at 06:59, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> On 21/04/2021 07:28, Nicolas Boichat wrote:
> > Hi!
> >
> > This is just a rebase of the v11, untested (but it seems like
> > Neil Armstrong recently tested it), with small changes in
> > binding and dts. v11 cover follows:
> >
> > Follow-up on the v5 [1], things have gotten significantly
> > better in the last year, thanks to the efforts on Bifrost
> > support by the Collabora team (and probably others I'm not
> > aware of).
> >
> > I've been testing this series on a MT8183/kukui device, with a
> > chromeos-5.10 kernel [2], and got basic Chromium OS UI up with
> > mesa 20.3.2 (lots of artifacts though).
> >
> > devfreq is currently not supported, as we'll need:
> >  - Clock core support for switching the GPU core clock (see 2/4).
> >  - Platform-specific handling of the 2-regulator (see 3/4).
> >
> > Since the latter is easy to detect, patch 3/4 just disables
> > devfreq if the more than one regulator is specified in the
> > compatible matching table.
> >
> > [1] https://patchwork.kernel.org/project/linux-mediatek/cover/20200306041345.259332-1-drinkcat@xxxxxxxxxxxx/
> > [2] https://crrev.com/c/2608070
> >
> > Changes in v13:
> >  - devfreq: Fix conflict resolution mistake when rebasing, didn't
> >    even compile. Oops.
> >
> > Changes in v12:
> >  - binding: Fix min/maxItems logic (Rob Herring)
> >  - Add gpu node to mt8183-pumpkin.dts as well (Neil Armstrong).
> >
> > Changes in v11:
> >  - binding: power-domain-names not power-domainS-names
> >  - mt8183*.dts: remove incorrect supply-names
> >
> > Changes in v10:
> >  - Fix the binding to make sure sram-supply property can be provided.
> >
> > Changes in v9:
> >  - Explain why devfreq needs to be disabled for GPUs with >1
> >    regulators.
> >
> > Changes in v8:
> >  - Use DRM_DEV_INFO instead of ERROR
> >
> > Changes in v7:
> >  - Fix GPU ID in commit message
> >  - Fix GPU ID in commit message
> >
> > Changes in v6:
> >  - Rebased, actually tested with recent mesa driver.
> >  - Add gpu regulators to kukui dtsi as well.
> >  - Power domains are now attached to spm, not scpsys
> >  - Drop R-B.
> >  - devfreq: New change
> >  - Context conflicts, reflow the code.
> >  - Use ARRAY_SIZE for power domains too.
> >
> > Changes in v5:
> >  - Rename "2d" power domain to "core2"
> >  - Rename "2d" power domain to "core2" (keep R-B again).
> >  - Change power domain name from 2d to core2.
> >
> > Changes in v4:
> >  - Add power-domain-names description
> >    (kept Alyssa's reviewed-by as the change is minor)
> >  - Add power-domain-names to describe the 3 domains.
> >    (kept Alyssa's reviewed-by as the change is minor)
> >  - Add power domain names.
> >
> > Changes in v3:
> >  - Match mt8183-mali instead of bifrost, as we require special
> >    handling for the 2 regulators and 3 power domains.
> >
> > Changes in v2:
> >  - Use sram instead of mali_sram as SRAM supply name.
> >  - Rename mali@ to gpu@.
> >
> > Nicolas Boichat (4):
> >   dt-bindings: gpu: mali-bifrost: Add Mediatek MT8183
> >   arm64: dts: mt8183: Add node for the Mali GPU
> >   drm/panfrost: devfreq: Disable devfreq when num_supplies > 1
> >   drm/panfrost: Add mt8183-mali compatible string
> >
> >  .../bindings/gpu/arm,mali-bifrost.yaml        |  30 ++++-
> >  arch/arm64/boot/dts/mediatek/mt8183-evb.dts   |   5 +
> >  .../arm64/boot/dts/mediatek/mt8183-kukui.dtsi |   5 +
> >  .../boot/dts/mediatek/mt8183-pumpkin.dts      |   5 +
> >  arch/arm64/boot/dts/mediatek/mt8183.dtsi      | 105 ++++++++++++++++++
> >  drivers/gpu/drm/panfrost/panfrost_devfreq.c   |   9 ++
> >  drivers/gpu/drm/panfrost/panfrost_drv.c       |  10 ++
> >  7 files changed, 168 insertions(+), 1 deletion(-)
> >
>
> Seems this version is ready to be applied if we get a review on the DT ?
>
> Mathias ? could you have a look ?
>

Given Rob has Acked the DT bindings, I think it's OK to apply patches
1, 3 and 4 via drm-misc, letting Mediatek people sort out the DT changes.

My two unsolicited cents :-)

Ezequiel