Re: [PATCH 5/6] arm64: dts: qcom: qcs6490-radxa-dragon-q6a: Enable GPU and display pipeline

[Neil Armstrong <neil.armstrong@linaro.org>]

Hi,

On 5/22/26 08:06, Graham O'Connor wrote:
> Enable the GPU clock controller (gpucc), GMU, display clock controller
> (dispcc), and MDSS display subsystem.
> 
> Add DisplayPort HPD pinctrl state for GPIO47 and wire up the DP output
> pipeline through the RA620 DP-to-HDMI bridge. The RA620 is a passive
> hardware bridge requiring no driver - it converts DP to HDMI
> autonomously. Add the dp-connector and hdmi-connector nodes to complete
> the display graph.
> 
> Disable DSI, DSI PHY, eDP, and eDP PHY as these interfaces are not
> present on the Radxa Dragon Q6A hardware.
> 
> Tested on Radxa Dragon Q6A (QCS6490) with RA620 DP-to-HDMI bridge
> connected to an HDMI monitor.
> 
> Signed-off-by: Graham O'Connor <graham.oconnor@gmail.com>
> ---
>   .../dts/qcom/qcs6490-radxa-dragon-q6a.dts     | 85 +++++++++++++++++++
>   1 file changed, 85 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/qcs6490-radxa-dragon-q6a.dts b/arch/arm64/boot/dts/qcom/qcs6490-radxa-dragon-q6a.dts
> index 4003837ad..e8ad6e666 100644
> --- a/arch/arm64/boot/dts/qcom/qcs6490-radxa-dragon-q6a.dts
> +++ b/arch/arm64/boot/dts/qcom/qcs6490-radxa-dragon-q6a.dts
> @@ -1113,3 +1113,88 @@ &pcie1 {
>   &eud {
>   	status = "disabled";
>   };
> +
> +&gpucc {
> +	status = "okay";
> +};
> +
> +&gmu {
> +	status = "okay";
> +};
> +
> +&dispcc {
> +	status = "okay";
> +};
> +
> +&mdss {
> +	status = "okay";
> +};
> +
> +&tlmm {
> +	dp_hot_plug_det: dp-hot-plug-det-state {
> +		pins = "gpio47";
> +		function = "dp_hot";
> +		bias-disable;
> +	};
> +};
> +
> +/ {
> +	hdmi-bridge {
> +		compatible = "dp-connector";

This is not the right way to enable the HDMI connector.

This patch https://lore.kernel.org/all/20250914-radxa-dragon-q6a-v2-5-045f7e92b3bb@radxa.com/
is the right way by exposing the HDMI bridge and setting the right usb_1_qmpphy data lanes.

Neil

> +		label = "hdmi";
> +		type = "full-size";
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&dp_hot_plug_det>;
> +		ports {
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +			port@0 {
> +				reg = <0>;
> +				hdmi_bridge_in: endpoint {
> +					remote-endpoint = <&usb_dp_qmpphy_out_dp>;
> +				};
> +			};
> +			port@1 {
> +				reg = <1>;
> +				hdmi_bridge_out: endpoint {
> +					remote-endpoint = <&hdmi_connector_in>;
> +				};
> +			};
> +		};
> +	};
> +
> +	hdmi-connector {
> +		compatible = "hdmi-connector";
> +		label = "hdmi";
> +		type = "a";
> +		port {
> +			hdmi_connector_in: endpoint {
> +				remote-endpoint = <&hdmi_bridge_out>;
> +			};
> +		};
> +	};
> +};
> +
> +&mdss_dp {
> +	status = "okay";
> +};
> +
> +&mdss_dp_out {
> +	data-lanes = <0 1>;
> +};
> +
> +&mdss_dsi {
> +	status = "disabled";
> +};
> +
> +&mdss_dsi_phy {
> +	status = "disabled";
> +};
> +
> +&mdss_edp {
> +	status = "disabled";
> +};
> +
> +&mdss_edp_phy {
> +	status = "disabled";
> +};