Hello, I’m working on the coreboot port for a laptop which uses the N200 (AlderLake-N). The built in LCD and HDMI port are working correctly but I am having problems with driving an external display over USB. The Linux kernel (6.5.0-27-generic in Ubuntu 23.10) gives a message that says: i915 0000:00:02.0: [drm] *ERROR* Timeout waiting for DDI BUF D to get active The timeout occurs in hsw_wait_for_power_well_enable(). I have put the full dmesg output of the drm_WARN_ON() messages on Pastebin[1]. I’m guessing something in the FSP isn’t being correctly configured but I don’t know whether it is graphics, USB, or power related. Thanks in advance for any advice on where to look. -Andy. 1. https://pastebin.com/p3JTYpTC
