Re: [PATCH v2 4/8] arm64: dts: allwinner: Add ARM Mali GPU node for H6

Maxime Ripard
2019-04-11T15:50:25Z

[-- Attachment #1: Type: text/plain, Size: 3855 bytes --]

On Thu, Apr 11, 2019 at 05:42:56PM +0200, Jernej Škrabec wrote:
> Dne četrtek, 11. april 2019 ob 17:27:52 CEST je Maxime Ripard napisal(a):
> > On Thu, Apr 11, 2019 at 05:23:25PM +0200, Jernej Škrabec wrote:
> > > Dne četrtek, 11. april 2019 ob 17:20:04 CEST je Clément Péron napisal(a):
> > > > Hi,
> > > >
> > > > On Thu, 11 Apr 2019 at 17:05, Jernej Škrabec <jernej.skrabec@siol.net>
> > >
> > > wrote:
> > > > > Dne četrtek, 11. april 2019 ob 12:57:16 CEST je Clément Péron
> napisal(a):
> > > > > > Add the mali gpu node to the H6 device-tree.
> > > > > >
> > > > > > Signed-off-by: Clément Péron <peron.clem-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> > > > > > ---
> > > > > >
> > > > > > arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi | 14 ++++++++++++++
> > > > > > 1 file changed, 14 insertions(+)
> > > > > >
> > > > > > diff --git a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi index
> > > > > > e0dc4a05c1ba..196753110434 100644
> > > > > > --- a/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > +++ b/arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi
> > > > > > @@ -157,6 +157,20 @@
> > > > > >
> > > > > > allwinner,sram = <&ve_sram 1>;
> > > > > >
> > > > > > };
> > > > > >
> > > > > > + gpu: gpu@1800000 {
> > > > > > + compatible = "allwinner,sun50i-h6-mali",
> > > > > > + "arm,mali-t720";
> > > > > > + reg = <0x01800000 0x4000>;
> > > > > > + interrupts = <GIC_SPI 84
> > > > >
> > > > > IRQ_TYPE_LEVEL_HIGH>,
> > > > >
> > > > > > + <GIC_SPI 85
> > > > >
> > > > > IRQ_TYPE_LEVEL_HIGH>,
> > > > >
> > > > > > + <GIC_SPI 83
> > > > >
> > > > > IRQ_TYPE_LEVEL_HIGH>;
> > > > >
> > > > > > + interrupt-names = "job", "mmu", "gpu";
> > > > > > + clocks = <&ccu CLK_GPU>, <&ccu CLK_BUS_GPU>;
> > > > > > + clock-names = "core", "bus";
> > > > > > + resets = <&ccu RST_BUS_GPU>;
> > > > > > + status = "disabled";
> > > > >
> > > > > Usually self sufficient peripherals are enabled by default in DTSI.
> > > >
> > > > I follow the other Mali Midgard (rk3399, rk3288) syntax.
> > > > But I think you're right here, will go for an update I think.
> > >
> > > I quickly checked A64 and H5 DTSI and both have GPU enabled by default
> > > (status property is not set).
> >
> > I asked myself the same question, but the H6 seems to have a supply
> > wired to the GPU, while the H3 and H5 do not. So I'm not sure we want
> > to enable it on all the boards, even though some might have left out
> > the GPU supply which will result in a non-working GPU (I assume?)
>
> It's true that GPU doesn't work at all without power supply. Even worse, ARM
> kernel driver just hangs whole SoC if it tries to use unpowered GPU.
>
> I checked few datasheets and almost none of them have GPU power supply, except
> H5, where GPU is enabled by default in DTSI.

I guess we should fix that then.

> Yeah, I guess it's more safe to explicitly enable it in board DT.

It's also something we do for the CPU, even though the CPU should be
obviously be powered before starting Linux...

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

--
You received this message because you are subscribed to the Google Groups "linux-sunxi" group.
To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
For more options, visit https://groups.google.com/d/optout.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]