Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Thu, 11 Apr 2019 17:50:25 +0200
From:   Maxime Ripard <maxime.ripard@bootlin.com>
To:     Jernej =?utf-8?Q?=C5=A0krabec?= <jernej.skrabec@siol.net>
Cc:     =?utf-8?B?Q2zDqW1lbnQgUMOpcm9u?= <peron.clem@gmail.com>,
        Rob Herring <robh+dt@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
        Icenowy Zheng <icenowy@aosc.io>,
        Jagan Teki <jagan@amarulasolutions.com>,
        devicetree <devicetree@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        dri-devel@lists.freedesktop.org, linux-sunxi@googlegroups.com
Subject: Re: [PATCH v2 4/8] arm64: dts: allwinner: Add ARM Mali GPU node for
 H6
Message-ID: <20190411155025.d5hmbw2jzhp3wyuq@flea>
References: <20190411105720.32357-1-peron.clem@gmail.com>
 <2797515.ZAugZ1JPiN@jernej-laptop>
 <20190411152752.qlabx7heh74dy2ao@flea>
 <5149757.GgN2G91tE9@jernej-laptop>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha256;
        protocol="application/pgp-signature"; boundary="ughvejlzbua5n4db"
Content-Disposition: inline
In-Reply-To: <5149757.GgN2G91tE9@jernej-laptop>
User-Agent: NeoMutt/20180716
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


--ughvejlzbua5n4db
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Thu, Apr 11, 2019 at 05:42:56PM +0200, Jernej =C5=A0krabec wrote:
> Dne =C4=8Detrtek, 11. april 2019 ob 17:27:52 CEST je Maxime Ripard napisa=
l(a):
> > On Thu, Apr 11, 2019 at 05:23:25PM +0200, Jernej =C5=A0krabec wrote:
> > > Dne =C4=8Detrtek, 11. april 2019 ob 17:20:04 CEST je Cl=C3=A9ment P=
=C3=A9ron napisal(a):
> > > > Hi,
> > > >
> > > > On Thu, 11 Apr 2019 at 17:05, Jernej =C5=A0krabec <jernej.skrabec@s=
iol.net>
> > >
> > > wrote:
> > > > > Dne =C4=8Detrtek, 11. april 2019 ob 12:57:16 CEST je Cl=C3=A9ment=
 P=C3=A9ron
> napisal(a):
> > > > > > Add the mali gpu node to the H6 device-tree.
> > > > > >
> > > > > > Signed-off-by: Cl=C3=A9ment P=C3=A9ron <peron.clem@gmail.com>
> > > > > > ---
> > > > > >
> > > > > >  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 =3D <&ve_sram 1>;
> > > > > >
> > > > > >               };
> > > > > >
> > > > > > +             gpu: gpu@1800000 {
> > > > > > +                     compatible =3D "allwinner,sun50i-h6-mali",
> > > > > > +                                  "arm,mali-t720";
> > > > > > +                     reg =3D <0x01800000 0x4000>;
> > > > > > +                     interrupts =3D <GIC_SPI 84
> > > > >
> > > > > IRQ_TYPE_LEVEL_HIGH>,
> > > > >
> > > > > > +                                  <GIC_SPI 85
> > > > >
> > > > > IRQ_TYPE_LEVEL_HIGH>,
> > > > >
> > > > > > +                                  <GIC_SPI 83
> > > > >
> > > > > IRQ_TYPE_LEVEL_HIGH>;
> > > > >
> > > > > > +                     interrupt-names =3D "job", "mmu", "gpu";
> > > > > > +                     clocks =3D <&ccu CLK_GPU>, <&ccu CLK_BUS_=
GPU>;
> > > > > > +                     clock-names =3D "core", "bus";
> > > > > > +                     resets =3D <&ccu RST_BUS_GPU>;
> > > > > > +                     status =3D "disabled";
> > > > >
> > > > > Usually self sufficient peripherals are enabled by default in DTS=
I.
> > > >
> > > > 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, e=
xcept
> 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

--ughvejlzbua5n4db
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iHUEABYIAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCXK9iQQAKCRDj7w1vZxhR
xW8KAQC6G/zptIZMa3Iez/W7WOhXWk54gWQ0gUOe1wOvm5zMFgEAkYt6r8m5dYvW
QFoyycKpJudgsTM0htXFB3AyjlPEag8=
=fNBG
-----END PGP SIGNATURE-----

--ughvejlzbua5n4db--