<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - Trying to set mode 3840x2160 at 60 Hz results in a crash" href="https://bugs.freedesktop.org/show_bug.cgi?id=95392#c10">Comment # 10</a> on <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - Trying to set mode 3840x2160 at 60 Hz results in a crash" href="https://bugs.freedesktop.org/show_bug.cgi?id=95392">bug 95392</a> from <a class="email" href="mailto:ville.syrjala@linux.intel.com" title="Ville Syrjala <ville.syrjala@linux.intel.com>"> Ville Syrjala</a> <pre>(In reply to Oli from <a href="show_bug.cgi?id=95392#c9">comment #9</a>) > (In reply to Ville Syrjala from <a href="show_bug.cgi?id=95392#c8">comment #8</a>) > > (In reply to Oli from <a href="show_bug.cgi?id=95392#c7">comment #7</a>) > > > (In reply to Ville Syrjala from <a href="show_bug.cgi?id=95392#c3">comment #3</a>) > > > > [ 12.914535] [drm:intel_update_cdclk] Current CD clock rate: 450000 kHz > > > > [ 91.861529] [drm:intel_dump_crtc_timings] crtc timings: 533280 3840 3848 > > > > 3992 4000 2160 2214 2219 2222, type: 0x0 flags: 0x9 > > > > > > > > Your cdclk is too low for that mode. I have a branch which has the required > > > > bits to adjust cdclk dynamically on SKL: > > > > git://github.com/vsyrjala/linux.git skl_bxt_cdclk_part_2 > > > > > > > > Can you test with that branch? > > > > > > I did and it seems to works, at least the display didn't blank and xrandr > > > reports 60 Hz. Though, I have no way to tell if this is really the case, > > > because my display won't show this information. > > > > > > See the attached dmesg output for more information. I used the same > > > drm.debug settings as before. > > > > > > [ 9.195675] [drm:intel_update_cdclk] Current CD clock rate: 450000 kHz, > > VCO: 8100000 kHz, ref: 24000 kHz > > [ 9.195677] [drm:intel_update_max_cdclk] Max CD clock rate: 675000 kHz > > [ 9.195678] [drm:intel_update_max_cdclk] Max dotclock rate: 675000 kHz > > [ 70.790172] [drm:intel_dump_crtc_timings] crtc timings: 533280 3840 3848 > > 3992 4000 2160 2214 2219 2222, type: 0x0 flags: 0x9 > > [ 70.790188] [drm:intel_modeset_checks] New cdclk calculated to be atomic > > 540000, actual 540000 > > [ 71.866294] [drm:skl_set_cdclk] Changing CDCLK to 540000 kHz (VCO 8100000 > > kHz) > > [ 71.872408] [drm:intel_update_cdclk] Current CD clock rate: 540000 kHz, > > VCO: 8100000 kHz, ref: 24000 kHz > > > > So everything is looking good. > > > > > > > > PS: Is this fix going upstream some time? > > > > It's being reviewed now, so should land soonish, I hope. > > This has not really something to do with the bug, but how are these numbers > to interpret? I mean, shouldn't there be something like a '60' somewhere? For the refresh rate? That'd be 'dotclock/htotal/vtotal' so in this case 533280*1000/4000/2222 = 60.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are on the CC list for the bug.</li> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>