Hi Eric,
Am 18.08.2015 um 23:54 schrieb Eric Anholt:
> VC4 is the GPU (display and 3D) subsystem present on the 2835 and some
> other Broadcom SoCs.
>
> This binding follows the model of msm, imx, sti, and others, where
> there is a subsystem node for the whole GPU, with nodes for the
> individual HW components within it.
>
> Signed-off-by: Eric Anholt <eric at anholt.net>
> ---
>
> v2: Extend the commit message, fix several nits from Stephen Warren.
>
> .../devicetree/bindings/gpu/brcm,bcm-vc4.txt | 79
> ++++++++++++++++++++++
> 1 file changed, 79 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/gpu/brcm,bcm-vc4.txt
>
> diff --git a/Documentation/devicetree/bindings/gpu/brcm,bcm-vc4.txt
> b/Documentation/devicetree/bindings/gpu/brcm,bcm-vc4.txt
> new file mode 100644
> index 0000000..1b9fedc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpu/brcm,bcm-vc4.txt
> @@ -0,0 +1,79 @@
> +Broadcom VC4 GPU
> +
> +The VC4 device present on the Raspberry Pi includes a display system
> +with HDMI output and the HVS scaler for compositing display planes.
> +
> +Required properties for VC4:
> +- compatible: Should be "brcm,vc4"
> +- crtcs: List of phandles of pixelvalve scanout engines
> +- hvss: List of phandles of HVS video scalers
> +- encoders: List of phandles of output encoders (HDMI, SDTV)
> +
> +Required properties for Pixel Valve:
> +- compatible: Should be "brcm,vc4-pixelvalve"
> +- reg: Physical base address and length of the PV's registers
> +- interrupts: The interrupt number
> + See bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
> +
> +Required properties for HVS:
> +- compatible: Should be "brcm,vc4-hvs"
> +- reg: Physical base address and length of the HVS's registers
> +- interrupts: The interrupt number
> + See bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
> +
> +Required properties for HDMI
> +- compatible: Should be "brcm,vc4-hdmi"
> +- reg: Physical base address and length of the two register
> ranges
> + ("HDMI" and "HD", in that order)
> +- interrupts: The interrupt numbers
> + See bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
> +- ddc: phandle of the I2C controller used for DDC EDID probing
> +- crtc: phandle to the pixelvalve CRTC the HDMI encoder is
> attached to
> +
> +Optional properties for HDMI:
> +- hpd-gpio: The GPIO pin for HDMI hotplug detect (if it doesn't appear
> + as an interrupt/status bit in the HDMI controller
> + itself). See bindings/pinctrl/brcm,bcm2835-gpio.txt
> +
> +Example:
> +pv0: brcm,vc4-pixelvalve at 7e206000 {
AFAIK the DT node name should describe the function and usually don't
have a vendor prefix. Here some possible suggestions without deeper
knowledge of the hardware function:
pv0: pixelvalve
> + compatible = "brcm,vc4-pixelvalve";
> + reg = <0x7e206000 0x100>;
> + interrupts = <2 13>; /* pwa2 */
> +};
> +
> +pv1: brcm,vc4-pixelvalve at 7e207000 {
pv1: pixelvalve
> + compatible = "brcm,vc4-pixelvalve";
> + reg = <0x7e207000 0x100>;
> + interrupts = <2 14>; /* pwa1 */
> +};
> +
> +pv2: brcm,vc4-pixelvalve at 7e807000 {
pv2: pixelvalve
> + compatible = "brcm,vc4-pixelvalve";
> + reg = <0x7e807000 0x100>;
> + interrupts = <2 10>; /* pixelvalve */
> +};
> +
> +hvs: brcm,hvs at 7e400000 {
hvs: hvs
> + compatible = "brcm,vc4-hvs";
> + reg = <0x7e400000 0x6000>;
> + interrupts = <2 1>;
> +};
> +
> +hdmi: brcm,vc4-hdmi at 7e902000 {
hdmi: hdmi
> + compatible = "brcm,vc4-hdmi";
> + reg = <0x7e902000 0x600>,
> + <0x7e808000 0x100>;
> + interrupts = <2 8>, <2 9>;
> + ddc = <&i2c2>;
> + hpd-gpio = <&gpio 46 GPIO_ACTIVE_HIGH>;
> + crtc = <&pv2>;
> +};
> +
> +vc4: vc4 at 0x7e4c0000 {
vc4: gpu
Regards
Stefan
> + compatible = "brcm,vc4";
> +
> + crtcs = <&pv0>, <&pv1>, <&pv2>;
> + encoders = <&hdmi>;
> + hvss = <&hvs>;
> +};
>
