Hi all,
We are trying the display port for i.MX8QM with the BSP Yocto Dunfell (kernel 5.4.142).
the device tree is as shown below.
&hdmi {
compatible = "cdn,imx8qm-dp";
firmware-name = "dpfw.bin";
lane-mapping = <0x1b>;
status = "okay";
};
With this setup the DP is working properly for 4K@60fps (4 lanes)
But we got some errors with the 1080P panel (2 lanes)
the log is shown below.
---------------------------------------------------------------------------------
[ 1.660874] [drm] HDP FW Version - ver 23029 verlib 20560
[ 1.733496] imx-drm display-subsystem: bound 56268000.hdmi (ops cdns_mhdp_imx_ops)
[ 1.737970] imx6q-pcie 5f000000.pcie: PCIe PLL locked after 0 us.
[ 1.742196] [drm] Initialized imx-drm 1.0.0 20120507 for display-subsystem on minor 0
[ 1.766754] cdns-mhdp-imx 56268000.hdmi: 0,ff,ff,ff,ff,ff,ff,0
[ 1.778421] [drm] Mode: 1920x1080p140120
[ 1.841808] [drm] DP link id: , 0x0 0x0 0x0 0x0 0x0 0x0
[ 1.843973] [drm] DP revision: 0x14
[ 1.843980] [drm] DP rate: 270000 Mbps
[ 1.843983] [drm] DP number of lanes: 2
[ 1.843987] [drm] DP capabilities: 0x1
[ 2.000161] cdns-mhdp-imx 56268000.hdmi: [drm:cdns_mhdp_config_video] *ERROR* tu error, clk:140120, lanes:2, rate:270
[ 2.000176] cdns-mhdp-imx 56268000.hdmi: [drm:cdns_mhdp_config_video] *ERROR* config video failed: -22
[ 2.000192] cdns-mhdp-imx 56268000.hdmi: [drm:cdns_dp_bridge_mode_set] *ERROR* Failed to config video -22
[ 2.615036] cdns-mhdp-imx 56268000.hdmi: [drm:cdns_mhdp_train_link] *ERROR* training failed: -110
[ 2.615051] cdns-mhdp-imx 56268000.hdmi: [drm:cdns_mhdp_train_link] *ERROR* Failed to start training -110
[ 2.615064] cdns-mhdp-imx 56268000.hdmi: [drm:cdn_dp_bridge_enable] *ERROR* Failed link train -110
----------------------------------------------------------------------
Is dp-lane-mapping = <0x1b>; has to change for 2 lanes?
Is anything besides the device tree have to change?
Thanks!
