Here are the logs on the vendor side (grepping for drm and edid): root@radxa-zero3:~# journalctl -k -b 0 | grep -e hdmi -e drm Apr 08 11:26:19 radxa-zero3 kernel: OF: fdt: Reserved memory: failed to reserve memory for node 'drm-logo@0': base 0x0000000000000000, size 0 MiB Apr 08 11:26:19 radxa-zero3 kernel: OF: fdt: Reserved memory: failed to reserve memory for node 'drm-cubic-lut@0': base 0x0000000000000000, size 0 MiB Apr 08 11:26:19 radxa-zero3 kernel: platform fe040000.vop: Fixed dependency cycle(s) with /hdmi@fe0a0000 Apr 08 11:26:19 radxa-zero3 kernel: platform fe0a0000.hdmi: Fixed dependency cycle(s) with /vop@fe040000 Apr 08 11:26:19 radxa-zero3 kernel: [drm] all windows should be assigned, full plane mask: Cluster0 | Cluster1 | Esmart0 | Esmart1 | Smart0 | Smart1[0x3f], current plane mask: [0x0 Apr 08 11:26:19 radxa-zero3 kernel: [drm] use default plane mask Apr 08 11:26:19 radxa-zero3 kernel: rockchip-vop2 fe040000.vop: [drm:vop2_bind] vp0 assign plane mask: Cluster0 | Cluster1 | Esmart0 | Esmart1 | Smart0 | Smart1[0x3f], primary plane phy id: Smart0[4] Apr 08 11:26:19 radxa-zero3 kernel: rockchip-vop2 fe040000.vop: [drm:vop2_bind] vp1 assign plane mask: [0x0], primary plane phy id: INVALID[-1] Apr 08 11:26:19 radxa-zero3 kernel: rockchip-vop2 fe040000.vop: [drm:vop2_bind] vp2 assign plane mask: [0x0], primary plane phy id: INVALID[-1] Apr 08 11:26:19 radxa-zero3 kernel: [drm] failed to init overlay plane Cluster0-win1 Apr 08 11:26:19 radxa-zero3 kernel: rockchip-drm display-subsystem: bound fe040000.vop (ops 0xffff80000939a0c0) Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: Looking up avdd-0v9-supply from device tree Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: Looking up avdd-0v9-supply property in node /hdmi@fe0a0000 failed Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: Looking up avdd-1v8-supply from device tree Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: Looking up avdd-1v8-supply property in node /hdmi@fe0a0000 failed Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: Detected HDMI TX controller v2.11a with HDCP (DWC HDMI 2.0 TX PHY) Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: registered DesignWare HDMI I2C bus driver Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: error -ENXIO: IRQ index 1 not found Apr 08 11:26:19 radxa-zero3 kernel: rockchip-drm display-subsystem: bound fe0a0000.hdmi (ops 0xffff8000093b2958) Apr 08 11:26:19 radxa-zero3 kernel: [drm] Initialized rockchip 4.0.0 20140818 for display-subsystem on minor 0 Apr 08 11:26:19 radxa-zero3 kernel: rockchip-drm display-subsystem: failed to parse loader memory Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: failed to get edid Apr 08 11:26:19 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: failed to get edid Apr 08 11:26:19 radxa-zero3 kernel: rockchip-vop2 fe040000.vop: [drm:vop2_crtc_atomic_enable] Update mode to 1280x720p60, type: 11(if:HDMI0, flag:0x0) for vp0 dclk: 74250000 Apr 08 11:26:19 radxa-zero3 kernel: rockchip-vop2 fe040000.vop: [drm:vop2_crtc_atomic_enable] set dclk_vop0 to 74250000, get 74250000 Apr 08 11:26:19 radxa-zero3 kernel: rockchip-drm display-subsystem: [drm] fb0: rockchipdrmfb frame buffer device Apr 08 11:26:19 radxa-zero3 kernel: rockchip-drm display-subsystem: [drm] run display error_event monitor Apr 08 11:26:19 radxa-zero3 kernel: rc rc0: dw_hdmi as /devices/platform/fe0a0000.hdmi/rc/rc0 Apr 08 11:26:19 radxa-zero3 kernel: input: dw_hdmi as /devices/platform/fe0a0000.hdmi/rc/rc0/input0 Apr 08 11:26:19 radxa-zero3 kernel: input: hdmi_cec_key as /devices/platform/fe0a0000.hdmi/dw-hdmi-cec.1.auto/input/input1 Apr 08 11:26:19 radxa-zero3 kernel: #0: rockchip-hdmi0 Apr 08 11:26:19 radxa-zero3 systemd[1]: Starting modprobe@drm.service - Load Kernel Module drm... Apr 08 11:26:19 radxa-zero3 systemd[1]: modprobe@drm.service: Deactivated successfully. Apr 08 11:26:19 radxa-zero3 systemd[1]: Finished modprobe@drm.service - Load Kernel Module drm. Apr 08 11:26:19 radxa-zero3 kernel: [drm] Initialized panfrost 1.2.0 20180908 for fde60000.gpu on minor 1 Apr 08 11:28:40 radxa-zero3 kernel: dwhdmi-rockchip fe0a0000.hdmi: failed to get edid root@radxa-zero3:~# This happens on multiple monitors and cables.

I disassembled my other radxa and swapped the SD cards, and it is just something funny with this hardware. I also just realized I bought a different configuration -- the one that works with `current` is a 2GB RAM version, and the one that has no HDMI (except on `vendor`) is a 4GB RAM version. I wonder if there are hardware differences.

Hm, I found the debs locally and installed them (along with the DTBs), still don't have HDMI. At this point I'd suspect the hardware but the vendor image works.

@Angel Luis Pérez Can you please upload your debian image. Plus kindly explain which hardware part is not working?

Just tried one of the latest images, but the HDD is not detected. To be more precise, it's detected randomly.