* Stephen Warren wrote:
> On 04/12/2012 11:44 AM, Thierry Reding wrote:
[...]
> And given that, I don't think we should name the node after some
> OS-specific software concept. Device tree is intended to model hardware.
[...]
> > Maybe one solution would be to have a top-level DRM device with a register
> > map from 0x54000000 to 0x547fffff, which the TRM designates as "host
> > registers". Then subnodes could be used for the subdevices.
> 
> Ah yes, just what I was thinking above:-)

I came up with the following:

	/* host1x */
	host1x : host1x@50000000 {
		reg = <0x50000000 0x00024000>;
		interrupts = <0 64 0x04   /* cop syncpt */
			      0 65 0x04   /* mpcore syncpt */
			      0 66 0x04   /* cop general */
			      0 67 0x04>; /* mpcore general */
	};

	/* graphics host */
	graphics@54000000 {
		compatible = "nvidia,tegra20-graphics";

		#address-cells = <1>;
		#size-cells = <1>;
		ranges = <0 0x54000000 0x08000000>;

		host1x = <&host1x>;

		/* video-encoding/decoding */
		mpe@54040000 {
			reg = <0x54040000 0x00040000>;
			interrupts = <0 68 0x04>;
		};

		/* video input */
		vi@54080000 {
			reg = <0x54080000 0x00040000>;
			interrupts = <0 69 0x04>;
		};

		/* EPP */
		epp@540c0000 {
			reg = <0x540c0000 0x00040000>;
			interrupts = <0 70 0x04>;
		}

		/* ISP */
		isp@54100000 {
			reg = <0x54100000 0x00040000>;
			interrupts = <0 71 0x04>;
		};

		/* 2D engine */
		gr2d@54140000 {
			reg = <0x54140000 0x00040000>;
			interrupts = <0 72 0x04>;
		};

		/* 3D engine */
		gr3d@54180000 {
			reg = <0x54180000 0x00040000>;
		};

		/* display controllers */
		disp1 : dc@54200000 {
			compatible = "nvidia,tegra20-dc";
			reg = <0x54200000 0x00040000>;
			interrupts = <0 73 0x04>;
		};

		disp2 : dc@54240000 {
			compatible = "nvidia,tegra20-dc";
			reg = <0x54240000 0x00040000>;
			interrupts = <0 74 0x04>;
		};

		/* outputs */
		lvds : rgb {
			compatible = "nvidia,tegra20-rgb";
		};

		hdmi : hdmi@54280000 {
			compatible = "nvidia,tegra20-hdmi";
			reg = <0x54280000 0x00040000>;
			interrupts = <0 75 0x04>;
		};

		tvo : tvo@542c0000 {
			compatible = "nvidia,tegra20-tvo";
			reg = <0x542c0000 0x00040000>;
			interrupts = <0 76 0x04>;
		};

		dsi : dsi@54300000 {
			compatible = "nvidia,tegra20-dsi";
			reg = <0x54300000 0x00040000>;
		};

		display-controllers = <&disp1 &disp2>;
		outputs = <&lvds &hdmi &tvo &dsi>;

		/* initial configuration */
		configuration {
			lvds {
				display-controller = <&disp1>;
				output = <&lvds>;
			};

			hdmi {
				display-controller = <&disp2>;
				output = <&hdmi>;
			};
		};
	};

I added an additional node for the initial configuration so that the driver
knows which mapping to setup at boot. What I don't quite see yet is where to
attach EDID data or pass the phandle to the I2C controller for DDC/EDID
probing. The initial configuration is certainly not the right place. Perhaps
the outputs property should be made a node instead:

	outputs {
		lvds_out {
			output = <&lvds>;
			edid = <&edid>;
		};

		hdmi_out {
			output = <&hdmi>;
			ddc = <&i2c2>;
		};
	};

But then "outputs" should probably become something like "connectors"
instead and the initial configuration refers to the "_out" phandles.

Thierry