On 14/04/2022 12:51, AngeloGioacchino Del Regno wrote: > Il 14/04/22 04:50, Nick Fan ha scritto: >> Add devicetree schema for Arm Mali Valhall GPU >> >> Define a compatible string for the Mali Valhall GPU >> for MediaTek's SoC platform. >> >> Signed-off-by: Nick Fan <Nick.Fan@xxxxxxxxxxxx> > > Hello Nick, > Unfortunately, this binding is completely wrong. I think that's unfair, although there is room for improvement. > First of all, there's no arm,mali-valhall driver upstream - this will be > managed > by panfrost later, yes, but right now there's no support. We need a binding agreed upon before support can be added. > Then, you're also setting opp-microvolt in a way that will never (or, at > least, > not anytime soon) be supported by the upstream driver, as it manages > only one > supply for devfreq scaling. The mt8183 binding (already in tree) is very similar. The binding also should be describing the hardware not what the driver supports. There are indeed limitations in Panfrost for supporting multiple supplies, but that's something that needs improving in the driver not a reason to block a (presumably correct) description of the hardware. I can't comments on whether the specifics of the mt8192 are correct. > Besides, please don't push bindings that have no upstream driver, > especially if > these are for downstream drivers requiring proprietary components, while a > completely open source implementation is in the works. More constructively, Alyssa has already posted a patch (as part of the series adding driver support) which would extend the existing Bifrost bindings to (pre-CSF) Valhall: https://lore.kernel.org/dri-devel/20220211202728.6146-2-alyssa.rosenzweig@xxxxxxxxxxxxx/ I'm not sure I see the point of having a separate binding document for Valhall considering the (pre-CSF) hardware is the same from the kernel perspective. Thanks, Steve
