Re: [PATCH v2] ARM: dts: bcm2835: Enable 3D rendering through V3D

[Maíra Canal <mcanal@xxxxxxxxxx>]

On 4/16/24 02:30, Stefan Wahren wrote:
> Hi Maíra,
>
> Am 16.04.24 um 03:02 schrieb Maíra Canal:
> > On 4/15/24 13:54, Andre Przywara wrote:
> > > On Mon, 15 Apr 2024 13:00:39 -0300
> > > Maíra Canal <mcanal@xxxxxxxxxx> wrote:
> > >
> > > Hi,
> > >
> > > > RPi 0-3 is packed with a GPU that provides 3D rendering capabilities to
> > > > the RPi. Currently, the downstream kernel uses an overlay to enable the
> > > > GPU and use GPU hardware acceleration. When deploying a mainline kernel
> > > > to the RPi 0-3, we end up without any GPU hardware acceleration
> > > > (essentially, we can't use the OpenGL driver).
> > > >
> > > > Therefore, enable the V3D core for the RPi 0-3 in the mainline kernel.
> > >
> > > So I think Krzysztof's initial comment still stands: What does that
> > > patch
> > > actually change? If I build those DTBs as of now, none of them has a
> > > status property in the v3d node. Which means it's enabled:
> > > https://github.com/devicetree-org/devicetree-specification/blob/main/source/chapter2-devicetree-basics.rst#status
> > >
> > > So adding an explicit 'status = "okay";' doesn't make a difference.
> > >
> > > What do I miss here?
> >
> > As mentioned by Stefan in the last version, in Raspberry Pi OS, there is
> > a systemd script which is trying to check for the V3D driver (/usr/lib
> > /systemd/scripts/gldriver_test.sh). Within the first check, "raspi-
> > config nonint is_kms" is called, which always seems to fail. What
> > "raspi-config" does is check if
> > /proc/device-tree/soc/v3d@7ec00000/status is equal to "okay". As
> > /proc/device-tree/soc/v3d@7ec00000/status doesn't exists, it returns
> > false.
> yes, but i also mention that the V3D driver starts without this patch.
> The commit message of this patch suggests this is a DT issue, which is not.
>
> I hadn't the time to update my SD card to Bookworm yet. Does the issue
> still exists with this version?

I'm using a 32-bit kernel and the recommended OS for 32-bit is Bullseye.
But I checked the Bookworm code and indeed, Bookworm doesn't check
the device tree [1].

I'm thinking about sending a patch to the Bullseye branch to fix this
issue.

[1] 
https://github.com/RPi-Distro/raspi-config/blob/966ed3fecc159ff3e69a774d74bfd716c04dafff/raspi-config#L128

Best Regards,
- Maíra

> > I'll send if I can improve the userspace tool by just checking if the
> > folder /proc/device-tree/soc/v3d@7ec00000/ exists. >>
> > Thanks for the explanation!
> >
> > Best Regards,
> > - Maíra
> >
> > > Cheers,
> > > Andre
> > >
> > > > Signed-off-by: Maíra Canal <mcanal@xxxxxxxxxx>
> > > > ---
> > > >
> > > > v1 -> v2:
> > > > https://lore.kernel.org/dri-devel/41694292-af1f-4760-a7b6-101ed5dd6f9d@xxxxxxx/T/
> > > >
> > > > * As mentioned by Krzysztof, enabling should be done in last place of
> > > >     override/extend. Therefore, I'm disabling V3D in the common dtsi
> > > >     and enabling in the last place of extend, i.e. the RPi DTS files.
> > > >
> > > >   arch/arm/boot/dts/broadcom/bcm2835-common.dtsi      | 1 +
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-a-plus.dts   | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-a.dts        | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-b-plus.dts   | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-b-rev2.dts   | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-b.dts        | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-cm1-io1.dts  | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-zero-w.dts   | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2835-rpi-zero.dts     | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2836-rpi-2-b.dts      | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2837-rpi-3-a-plus.dts | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b-plus.dts | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b.dts      | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2837-rpi-cm3-io3.dts  | 4 ++++
> > > >   arch/arm/boot/dts/broadcom/bcm2837-rpi-zero-2-w.dts | 4 ++++
> > > >   15 files changed, 57 insertions(+)
> > > >
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-common.dtsi
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-common.dtsi
> > > > index 9261b67dbee1..69e34831de51 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-common.dtsi
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-common.dtsi
> > > > @@ -139,6 +139,7 @@ v3d: v3d@7ec00000 {
> > > >               compatible = "brcm,bcm2835-v3d";
> > > >               reg = <0x7ec00000 0x1000>;
> > > >               interrupts = <1 10>;
> > > > +            status = "disabled";
> > > >           };
> > > >             vc4: gpu {
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-a-plus.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-a-plus.dts
> > > > index 069b48272aa5..495ab1dfd2ce 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-a-plus.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-a-plus.dts
> > > > @@ -128,3 +128,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-a.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-a.dts
> > > > index 2726c00431e8..4634d88ce3af 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-a.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-a.dts
> > > > @@ -121,3 +121,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-plus.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-plus.dts
> > > > index c57b999a4520..45fa0f6851fc 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-plus.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-plus.dts
> > > > @@ -130,3 +130,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-rev2.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-rev2.dts
> > > > index ae6d3a9586ab..c1dac5d704aa 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-rev2.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-b-rev2.dts
> > > > @@ -121,3 +121,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-b.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-b.dts
> > > > index 72764be75a79..72ca31f2a7d6 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-b.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-b.dts
> > > > @@ -115,3 +115,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-cm1-io1.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-cm1-io1.dts
> > > > index 3f9d198ac3ab..881a07d2f28f 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-cm1-io1.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-cm1-io1.dts
> > > > @@ -95,3 +95,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero-w.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero-w.dts
> > > > index 1f0b163e400c..1c7324067442 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero-w.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero-w.dts
> > > > @@ -134,6 +134,10 @@ &uart1 {
> > > >       status = "okay";
> > > >   };
> > > >   +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > +
> > > >   &wifi_pwrseq {
> > > >       reset-gpios = <&gpio 41 GPIO_ACTIVE_LOW>;
> > > >   };
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero.dts
> > > > index 539c19c10946..1568ddc78f22 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2835-rpi-zero.dts
> > > > @@ -117,3 +117,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2836-rpi-2-b.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2836-rpi-2-b.dts
> > > > index 79918033750e..8fab6293d1c7 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2836-rpi-2-b.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2836-rpi-2-b.dts
> > > > @@ -129,3 +129,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-a-plus.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-a-plus.dts
> > > > index 3548306dfbcb..dc45b56054c7 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-a-plus.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-a-plus.dts
> > > > @@ -156,3 +156,7 @@ &uart1 {
> > > >       pinctrl-0 = <&uart1_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b-plus.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b-plus.dts
> > > > index 2f1800cbc522..ce3a9f7ff529 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b-plus.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b-plus.dts
> > > > @@ -161,3 +161,7 @@ &uart1 {
> > > >   &wifi_pwrseq {
> > > >       reset-gpios = <&expgpio 1 GPIO_ACTIVE_LOW>;
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b.dts
> > > > index 61270340075c..e398546d105b 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2837-rpi-3-b.dts
> > > > @@ -149,6 +149,10 @@ &sdhost {
> > > >       bus-width = <4>;
> > > >   };
> > > >   +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > +
> > > >   &wifi_pwrseq {
> > > >       reset-gpios = <&expgpio 1 GPIO_ACTIVE_LOW>;
> > > >   };
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2837-rpi-cm3-io3.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2837-rpi-cm3-io3.dts
> > > > index 72d26d130efa..50471ada79b3 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2837-rpi-cm3-io3.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2837-rpi-cm3-io3.dts
> > > > @@ -94,3 +94,7 @@ &uart0 {
> > > >       pinctrl-0 = <&uart0_gpio14>;
> > > >       status = "okay";
> > > >   };
> > > > +
> > > > +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > diff --git a/arch/arm/boot/dts/broadcom/bcm2837-rpi-zero-2-w.dts
> > > > b/arch/arm/boot/dts/broadcom/bcm2837-rpi-zero-2-w.dts
> > > > index 85cf594724ef..876f697e7300 100644
> > > > --- a/arch/arm/boot/dts/broadcom/bcm2837-rpi-zero-2-w.dts
> > > > +++ b/arch/arm/boot/dts/broadcom/bcm2837-rpi-zero-2-w.dts
> > > > @@ -132,6 +132,10 @@ &uart1 {
> > > >       status = "okay";
> > > >   };
> > > >   +&v3d {
> > > > +    status = "okay";
> > > > +};
> > > > +
> > > >   &wifi_pwrseq {
> > > >       reset-gpios = <&gpio 41 GPIO_ACTIVE_LOW>;
> > > >   };
> >
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