TX2 Custom Board HDMI

Greetings!
Recently we’ve faced a problem with a custom carrier board we’ve develoved for TX2 embedded system. Due to PCB error we’ve connected HPD signal on the HDMI port to DP1_HPD (A33) instead of DP0_HPD, and the HDMI_AUX to DP1_AUX(A34/A35) instead of DP0-AUX (B34/35), while the information pairs are connected to DP0.
Is there any way to alter the internal logic to make this work by changing the source code?
Thank you for your answer.

Hi,
We are checking if this can be handled with software workaround. Will update.
If you plan to go to mass production, we would suggest fix the wrong pin connection in hardware design.

Hi,
We had an internal discussion on this. The combination of SOR1 + DPAUX0(HPD0) might work theoretically. However, it is not verified and guaranteed. You may modify device tree for a try. We would suggest correct the hardware design in the final product.

Hello!
Thanks for your response. The PCB errors are already terminated on the paper, but it will take a while for the production company to create the custom boards. I might need a little help from you.
I’ve made some changes in the dtsi files.

hardware/nvidia/platform/t18x/common/kernel-dts/t18x-common-platforms/tegra186-hdmi.dtsi

@@ -25,7 +25,9 @@
host1x {
sor1 {
status = “okay”;
// Original
// nvidia,ddc-i2c-bus = <&dp_aux_ch1_i2c>;
nvidia,ddc-i2c-bus = <&dp_aux_ch0_i2c>;
nvidia,active-panel = <&sor1_hdmi_display>;
hdmi-display {
status = “okay”;
@@ -45,7 +47,9 @@

  sor {
  	status = "okay";

// Original
// nvidia,ddc-i2c-bus = <&dp_aux_ch0_i2c>;
nvidia,ddc-i2c-bus = <&dp_aux_ch1_i2c>;
nvidia,active-panel = <&sor0_hdmi_display>;
hdmi-display {
status = “okay”;

hardware/nvidia/platform/t18x/common/kernel-dts/t18x-common-platforms/tegra186-quill-common.dtsi

@@ -575,12 +575,14 @@
sor{
status = “okay”;
nvidia,xbar-ctrl = <0 1 2 3 4>;
// Original
// nvidia,hpd-gpio = <&tegra_main_gpio TEGRA_MAIN_GPIO(P, 0) GPIO_ACTIVE_LOW>;
nvidia,hpd-gpio = <&tegra_main_gpio TEGRA_MAIN_GPIO(P, 1) GPIO_ACTIVE_LOW>;
panel-s-edp-uhdtv-15-6 {
nvidia,panel-bl-pwm-gpio = <&tegra_aon_gpio TEGRA_AON_GPIO(U, 5) 0>;
};
hdmi-display {
status = “disabled”;
status = “okay”;
};
dp-display {
status = “disabled”;
@@ -589,7 +591,9 @@
sor1 {
status = “okay”;
nvidia,xbar-ctrl = <0 1 2 3 4>;
// Original
// nvidia,hpd-gpio = <&tegra_main_gpio TEGRA_MAIN_GPIO(P, 1) GPIO_ACTIVE_LOW>;
nvidia,hpd-gpio = <&tegra_main_gpio TEGRA_MAIN_GPIO(P, 0) GPIO_ACTIVE_LOW>;
nvidia,active-panel = <&sor1_hdmi_display>;
hdmi-display {
status = “okay”;

Also I’ve made some minor changes in hdmi dtsi files to enable the sor hdmi interface. But with no success. What else can be changed to solve the issue?

There is no update from you for a period, assuming this is not an issue any more.
Hence we are closing this topic. If need further support, please open a new one.
Thanks

Hi,

Sorry to jump in. We need extra info from you.

  1. Please share the correct board schematic here and give us a brief description of your design. For example, dual HDMI or single HDMI port, and which ports are they using.

  2. Please share the dmesg.

  3. Please convert the dtb back to dts and share it here.

Please note that we cannot help you if the design does not match the design guide.