linux/Documentation/devicetree/bindings/video/renesas,du.txt
Laurent Pinchart 1b30dbde85 drm: rcar-du: Add support for external pixel clock
The DU uses the module functional clock as the default pixel clock, but
supports using an externally supplied pixel clock instead. Support this
by adding the external pixel clock to the DT bindings, and selecting the
clock automatically at runtime based on the requested mode pixel
frequency.

The input clock pins to DU channels routing is configurable, but
currently hardcoded to connect input clock i to channel i.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
2014-12-23 12:01:50 +02:00

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* Renesas R-Car Display Unit (DU)
Required Properties:
- compatible: must be one of the following.
- "renesas,du-r8a7779" for R8A7779 (R-Car H1) compatible DU
- "renesas,du-r8a7790" for R8A7790 (R-Car H2) compatible DU
- "renesas,du-r8a7791" for R8A7791 (R-Car M2) compatible DU
- reg: A list of base address and length of each memory resource, one for
each entry in the reg-names property.
- reg-names: Name of the memory resources. The DU requires one memory
resource for the DU core (named "du") and one memory resource for each
LVDS encoder (named "lvds.x" with "x" being the LVDS controller numerical
index).
- interrupt-parent: phandle of the parent interrupt controller.
- interrupts: Interrupt specifiers for the DU interrupts.
- clocks: A list of phandles + clock-specifier pairs, one for each entry in
the clock-names property.
- clock-names: Name of the clocks. This property is model-dependent.
- R8A7779 uses a single functional clock. The clock doesn't need to be
named.
- R8A7790 and R8A7791 use one functional clock per channel and one clock
per LVDS encoder. The functional clocks must be named "du.x" with "x"
being the channel numerical index. The LVDS clocks must be named
"lvds.x" with "x" being the LVDS encoder numerical index.
- In addition to the functional and encoder clocks, all DU versions also
support externally supplied pixel clocks. Those clocks are optional.
When supplied they must be named "dclkin.x" with "x" being the input
clock numerical index.
Required nodes:
The connections to the DU output video ports are modeled using the OF graph
bindings specified in Documentation/devicetree/bindings/graph.txt.
The following table lists for each supported model the port number
corresponding to each DU output.
Port 0 Port1 Port2
-----------------------------------------------------------------------------
R8A7779 (H1) DPAD 0 DPAD 1 -
R8A7790 (H2) DPAD LVDS 0 LVDS 1
R8A7791 (M2) DPAD LVDS 0 -
Example: R8A7790 (R-Car H2) DU
du: du@feb00000 {
compatible = "renesas,du-r8a7790";
reg = <0 0xfeb00000 0 0x70000>,
<0 0xfeb90000 0 0x1c>,
<0 0xfeb94000 0 0x1c>;
reg-names = "du", "lvds.0", "lvds.1";
interrupt-parent = <&gic>;
interrupts = <0 256 IRQ_TYPE_LEVEL_HIGH>,
<0 268 IRQ_TYPE_LEVEL_HIGH>,
<0 269 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&mstp7_clks R8A7790_CLK_DU0>,
<&mstp7_clks R8A7790_CLK_DU1>,
<&mstp7_clks R8A7790_CLK_DU2>,
<&mstp7_clks R8A7790_CLK_LVDS0>,
<&mstp7_clks R8A7790_CLK_LVDS1>;
clock-names = "du.0", "du.1", "du.2", "lvds.0", "lvds.1";
ports {
#address-cells = <1>;
#size-cells = <0>;
port@0 {
reg = <0>;
du_out_rgb: endpoint {
};
};
port@1 {
reg = <1>;
du_out_lvds0: endpoint {
};
};
port@2 {
reg = <2>;
du_out_lvds1: endpoint {
};
};
};
};