On Mon, 23 Apr 2018, Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx> wrote: > Hi > > I have a secondary monitor connected via USB-C adapter to HDMI. It > can manage resolutions up to 2560x1440. > > Most of the time, when the system is booted the resolution is detected > ok, but If I suspend the machine, or replug the screen, or alternate > to the text console, the resolution is "downgraded" to Full HD. > > I have added the paramter drm.debug=0x06 to my kernel option and I > have managed to catch this error when the resolution is not detected > properly: > > [ 4.941022] [drm:drm_mode_debug_printmodeline [drm]] Modeline > 77:"2560x1440" 60 241500 2560 2608 2640 2720 1440 1443 1448 1481 0x48 > 0x5 > [ 4.941046] [drm:drm_mode_prune_invalid [drm]] Not using 2560x1440 > mode: CLOCK_HIGH > > > On the other hand, when it works fine: > > [ 95.361838] [drm:drm_mode_debug_printmodeline [drm]] Modeline > 85:"2560x1440" 60 241500 2560 2608 2640 2720 1440 1443 1448 1481 0x48 > 0x5 > [ 95.928536] [drm:intel_dump_pipe_config [i915]] crtc timings: > 241500 2560 2608 2640 2720 1440 1443 1448 1481, type: 0x48 flags: 0x5 > [ 95.928546] [drm:intel_dump_pipe_config [i915]] port clock: 540000, > pipe src size: 2560x1440, pixel rate 241500 > > > The adapter is brand new (Xiaomi) and the cable should be of good > quality (ethernet capable). > > > Any ideas about how to debug this? The EDID seems fine, it seems > related to hock clock_high is calculated. CLOCK_HIGH is just a consequence of the link being downgraded, there's not enough bandwidth in the link for the mode. You have a bug open at freedesktop.org [1], please let's keep the discussion in one place. BR, Jani. [1] https://bugs.freedesktop.org/show_bug.cgi?id=106223 -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
