Hi Tarang, On Mon, Apr 07, 2025 at 11:10:23AM +0000, Tarang Raval wrote: > Hi Laurent, > > I’m trying to bring up HDMI on the Debix Model A board using the > mainline kernel, but I’m currently facing issues. > > I saw that you tested the patch for HDMI support on this board in > mainline, so I am hoping you could help me figure out what might be > missing. > > To clarify — I'm using the prebuilt image provided by Debix, but I replaced > the kernel image and the device tree (DTS) file in the /boot directory with > ones built from the mainline kernel. > > I’ve enabled the following configurations in the kernel: > CONFIG_DRM_DISPLAY_CONNECTOR=y > CONFIG_DRM_IMX8MP_DW_HDMI_BRIDGE=y > CONFIG_DRM_IMX8MP_HDMI_PVI=y > CONFIG_DRM_IMX_LCDIF=y > CONFIG_PHY_FSL_SAMSUNG_HDMI_PHY=y > > When I boot the board, I see the following HDMI/DRM related logs: > debix@imx8mp-debix:~$ dmesg | grep -iE "drm|hdmi" > [ 0.121979] /soc@0/bus@32c00000/display-bridge@32fc4000: Fixed dependency > cycle(s) with /soc@0/bus@32c00000/hdmi@32fd8000 > [ 0.122164] /soc@0/bus@32c00000/hdmi@32fd8000: Fixed dependency cycle(s) > with /soc@0/bus@32c00000/display-bridge@32fc4000 > [ 0.127417] /soc@0/bus@32c00000/hdmi@32fd8000: Fixed dependency cycle(s) > with /hdmi-connector > [ 0.127608] /hdmi-connector: Fixed dependency cycle(s) with > /soc@0/bus@32c00000/hdmi@32fd8000 > [ 1.947962] imx8mp-dw-hdmi-tx 32fd8000.hdmi: Detected HDMI TX controller > v2.13a with HDCP (SAMSUNG HDMI TX PHY) > [ 1.949220] imx8mp-dw-hdmi-tx 32fd8000.hdmi: registered DesignWare HDMI > I2C bus driver > [ 1.956365] [drm] Initialized imx-lcdif 1.0.0 for > 32fc6000.display-controller on minor 0 > [ 2.016601] imx-lcdif 32fc6000.display-controller: [drm] fb0: > imx-lcdifdrmfb frame buffer device > [ 8.380915] systemd[1]: Starting Load Kernel Module drm... > > > I also checked that the display's modeline is recognized under sysfs : > > root@imx8mp-debix:~# ls /sys/class/drm/card0-HDMI-A-1/ > connector_id dpms modes subsystem/ > ddc/ edid power/ uevent > device/ enabled status > > However, there is still no HDMI output on the display. Instead, > I only see a white blinking cursor on the screen.. I'm not sure > what I'm missing.
The white blinking cursor means the display is working from the kernel point of view. What are you expecting, are you running an X server or Wayland compositor ? > Could you please help me out or point me in the right direction? > > Thank you for your time. > > Best Regards, > Tarang -- Regards, Laurent Pinchart
