ARM HDLCD
This is a display controller found on several development platforms produced
by ARM Ltd and in more modern of its’ Fast Models. The HDLCD is an RGB
streamer that reads the data from a framebuffer and sends it to a single
digital encoder (DVI or HDMI).
Required properties:
- compatible: “arm,hdlcd”
- reg: Physical base address and length of the controller’s registers.
- interrupts: One interrupt used by the display controller to notify the
interrupt controller when any of the interrupt sources programmed in
the interrupt mask register have activated. - clocks: A list of phandle + clock-specifier pairs, one for each
entry in ‘clock-names’. - clock-names: A list of clock names. For HDLCD it should contain:
- “pxlclk” for the clock feeding the output PLL of the controller.
Required sub-nodes:
- port: The HDLCD connection to an encoder chip. The connection is modeled
using the OF graph bindings specified in
Documentation/devicetree/bindings/graph.txt.
Optional properties:
- memory-region: phandle to a node describing memory (see
Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt) to be
used for the framebuffer; if not present, the framebuffer may be located
anywhere in memory.
Example:
/ {
…
hdlcd@2b000000 {
compatible = "arm,hdlcd";
reg = <0 0x2b000000 0 0x1000>;
interrupts = <GIC_SPI 85 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&oscclk5>;
clock-names = "pxlclk";
port {
hdlcd_output: endpoint@0 {
remote-endpoint = <&hdmi_enc_input>;
};
};
};
/* HDMI encoder on I2C bus */
i2c@7ffa0000 {
....
hdmi-transmitter@70 {
compatible = ".....";
reg = <0x70>;
port@0 {
hdmi_enc_input: endpoint {
remote-endpoint = <&hdlcd_output>;
};
hdmi_enc_output: endpoint {
remote-endpoint = <&hdmi_1_port>;
};
};
};
};
hdmi1: connector@1 {
compatible = "hdmi-connector";
type = "a";
port {
hdmi_1_port: endpoint {
remote-endpoint = <&hdmi_enc_output>;
};
};
};
...
};
