Is there any better documentation on the HDMI subsystem in the IMX8M devices? I'm attempting to bring up a non-Linux based OS on the device, and am using u-boot as a starting point. The HDMI setup in u-boot seems to be restricted to CEA video standards of 480p, 720p, 1080p, and 2160p and fixed clock frequencies. I'd like to drive computer monitors of 1024x768, 1600x1200, etc. These require different clock rates than phy_cfg_t28hpc() appears to support. Would ungating and setting the video PLL to my required clock rate and calling imx8_hdmi_init with use_phy_pixel_clk set to zero be enough to use other pixel clock rates?