Re: [PATCH] media: qcom: venus: flip the venus/iris switch

[Dmitry Baryshkov]

On Fri, Nov 21, 2025 at 02:22:46PM +0100, Stephan Gerhold wrote:
> On Wed, Nov 19, 2025 at 05:18:18PM +0200, Dmitry Baryshkov wrote:
> > With the Iris and Venus driver having more or less feature parity for
> > "HFI 6xx" platforms and with Iris gaining support for SC7280, flip the
> > switch. Use Iris by default for SM8250 and SC7280, the platforms which
> > are supported by both drivers, and use Venus only if Iris is not
> > compiled at all. Use IS_ENABLED to strip out the code and data
> > structures which are used by the disabled platforms.
> > 
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
> 
> I think this will break the ChromeOS SC7280 platform, because the new
> Iris driver does not (yet) support the non-PAS/TZ startup sequence.
> Given that this is a dead (never released) platform, it probably does
> not make sense blocking the switch from Venus to Iris, but it should be
> made clear in the commit message at least. And perhaps the affected DTs
> should be changed to disable Venus/Iris then.

Indeed, I totally forgot about SC7280 ChromeOS here.

> 
> It would be easy to add support for the non-PAS/TZ startup sequence in
> the Iris driver. The changes exist already [1], they are just stuck on
> the never ending discussion about how to model the additional
> video-firmware IOMMU entry in the DT for newer platforms [2]. Perhaps
> the existing legacy usage in SC7280 would be enough precedent to land
> this patch as-is, although I don't have access to any SC7280-based board
> for testing.

I think that for current platforms, which don't have that ABI defined,
we should use the upcoming iommu-maps, once the rework lands. We should
even be able to define it in the base DTSI, making sure that this entry
is ignored if TZ / PAS is available.

> 
> Thanks,
> Stephan
> 
> [1]: https://git.codelinaro.org/stephan.gerhold/linux/-/commit/14db4bfae9279a0e69a0a9d2ccdd684658916431
> [2]: https://lore.kernel.org/r/20250823155349.22344-2-krzysztof.kozlowski@xxxxxxxxxx/

-- 
With best wishes
Dmitry