In the Linux kernel, the following vulnerability has been resolved:
pmdomain: imx8mp-blk-ctrl: imx8mp_blk: Add fdcc clock to hdmimix domain
According to i.MX8MP RM and HDMI ADD, the fdcc clock is part of hdmi rx verification IP that should not enable for HDMI TX. But actually if the clock is disabled before HDMI/LCDIF probe, LCDIF will not get pixel clock from HDMI PHY and print the error logs:
[CRTC:39:crtc-2] vblank wait timed out WARNING: CPU: 2 PID: 9 at drivers/gpu/drm/drmatomichelper.c:1634 drmatomichelperwaitfor_vblanks.part.0+0x23c/0x260
Add fdcc clock to LCDIF and HDMI TX power domains to fix the issue.