On Mon, Feb 22, 2016 at 7:13 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: > On Wed, Feb 17, 2016 at 5:36 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: >> On Wed, Feb 17, 2016 at 8:18 AM, Daniel Vetter <daniel@xxxxxxxx> wrote: >>> On Tue, Feb 16, 2016 at 09:26:35AM -0800, Andy Lutomirski wrote: >>>> On Tue, Feb 16, 2016 at 9:12 AM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: >>>> > On Tue, Feb 16, 2016 at 8:12 AM, Daniel Vetter <daniel@xxxxxxxx> wrote: >>>> >> On Mon, Feb 15, 2016 at 06:58:33AM -0800, Andy Lutomirski wrote: >>>> >>> On Sun, Feb 14, 2016 at 6:59 PM, Andy Lutomirski <luto@xxxxxxxxxx> wrote: >>>> >>> > Hi- >>>> >>> > >>>> >>> > On 4.5-rc3 on a Dell XPS 13 9350 (Skylake i915, no nvidia on this >>>> >>> > model), shortly after resume, I saw a single black flash on the >>>> >>> > screen. The log said: >>>> >>> > >>>> >>> > [Feb13 07:05] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* >>>> >>> > CPU pipe A FIFO underrun >>>> >>> > >>>> >>> > I haven't seen this on 4.4. >>>> >>> > >>>> >>> > I'd be happy to dig up debugging info, but I don't know what would be >>>> >>> > useful. I have no i915 module options set. >>>> >>> >>>> >>> It's flashing quite frequently now, although I seem to get the >>>> >>> underrun warning only once per resume. >>>> >> >>>> >> We shut up the warning irq source to avoid hijacking an entire cpu core >>>> >> ;-) >>>> >> >>>> >> There's a fix from Matt right after 4.5-rc4 in Linus' branch. I'm hoping >>>> >> that should help. >>>> > >>>> > Do you mean: >>>> > >>>> > commit e2e407dc093f530b771ee8bf8fe1be41e3cea8b3 >>>> > Author: Matt Roper <matthew.d.roper@xxxxxxxxx> >>>> > Date: Mon Feb 8 11:05:28 2016 -0800 >>>> > >>>> > drm/i915: Pretend cursor is always on for ILK-style WM calculations (v2) >>>> > >>>> > If so, it didn't help. I'm currently doing a full rebuild just in >>>> > case I messed something up, though. >>>> > >>>> >>>> Definitely not fixed. It seems to be okay after a reboot until the >>>> first suspend/resume. >>>> >>>> This happened after resuming. Five cents says it's the root cause. >>> >>> That's interesting, but doesn't ring a bell unfortunately. Can you try to >>> attempt a bisect? >> >> I probably can, but it's very slow. Is there a reasonably >> straightforward way to instrument the watermark computation to see >> what's going wrong? I'm reasonably confident that the bug is in the >> resume code or in something that only happens on resume, since I still >> haven't seen underruns after rebooting before suspending. >> > > With some instrumentation applied, I got this: > > [ 369.471064] skl_update_wm(crtc-0): computed update > [ 369.471072] skl_update_other_pipe_wm(crtc-0): no change > [ 369.471075] skl_write_wm_values... > [ 369.471078] CRTC crtc-0 pipe A > [ 369.471083] wm_linetime = 121 > [ 369.471086] plane_wm level 0 plane 0 = 2147500036 > [ 369.471090] plane_wm level 0 plane 1 = 0 > [ 369.471094] plane_wm level 0 cursor = 2147500036 > [ 369.471097] plane_wm level 1 plane 0 = 2147516439 > [ 369.471101] plane_wm level 1 plane 1 = 0 > [ 369.471104] plane_wm level 1 cursor = 2147516439 > [ 369.471108] plane_wm level 2 plane 0 = 2147516448 > [ 369.471111] plane_wm level 2 plane 1 = 0 > [ 369.471115] plane_wm level 2 cursor = 0 > [ 369.471118] plane_wm level 3 plane 0 = 2147532837 > [ 369.471121] plane_wm level 3 plane 1 = 0 > [ 369.471125] plane_wm level 3 cursor = 0 > [ 369.471128] plane_wm level 4 plane 0 = 2147565639 > [ 369.471131] plane_wm level 4 plane 1 = 0 > [ 369.471135] plane_wm level 4 cursor = 0 > [ 369.471138] plane_wm level 5 plane 0 = 2147582038 > [ 369.471141] plane_wm level 5 plane 1 = 0 > [ 369.471145] plane_wm level 5 cursor = 0 > [ 369.471148] plane_wm level 6 plane 0 = 2147582044 > [ 369.471151] plane_wm level 6 plane 1 = 0 > [ 369.471155] plane_wm level 6 cursor = 0 > [ 369.471158] plane_wm level 7 plane 0 = 2147598443 > [ 369.471161] plane_wm level 7 plane 1 = 0 > [ 369.471164] plane_wm level 7 cursor = 0 > [ 369.471168] wm_trans plane 0 = 0 > [ 369.471171] wm_trans plane 1 = 0 > [ 369.471174] wm_trans cursor = 0 > [ 369.471182] CRTC crtc-1 pipe B > [ 369.471184] clean > [ 369.471186] CRTC crtc-2 pipe C > [ 369.471189] clean > [ 369.471226] skl_update_wm(crtc-0): no update > [ 372.068755] [drm:intel_cpu_fifo_underrun_irq_handler [i915]] > *ERROR* CPU pipe A FIFO underrun > [ 373.399396] skl_update_wm(crtc-0): computed update > [ 373.399408] skl_update_other_pipe_wm(crtc-0): no change > [ 373.399413] skl_write_wm_values... > [ 373.399418] CRTC crtc-0 pipe A > [ 373.399426] wm_linetime = 121 > [ 373.399431] plane_wm level 0 plane 0 = 2147500036 > [ 373.399438] plane_wm level 0 plane 1 = 0 > [ 373.399443] plane_wm level 0 cursor = 16388 > [ 373.399449] plane_wm level 1 plane 0 = 2147516439 > [ 373.399455] plane_wm level 1 plane 1 = 0 > [ 373.399460] plane_wm level 1 cursor = 32791 > [ 373.399465] plane_wm level 2 plane 0 = 2147516448 > [ 373.399471] plane_wm level 2 plane 1 = 0 > [ 373.399476] plane_wm level 2 cursor = 0 > [ 373.399481] plane_wm level 3 plane 0 = 2147532837 > [ 373.399486] plane_wm level 3 plane 1 = 0 > [ 373.399491] plane_wm level 3 cursor = 0 > [ 373.399497] plane_wm level 4 plane 0 = 2147565639 > [ 373.399502] plane_wm level 4 plane 1 = 0 > [ 373.399557] plane_wm level 4 cursor = 0 > [ 373.399562] plane_wm level 5 plane 0 = 2147582038 > [ 373.399568] plane_wm level 5 plane 1 = 0 > [ 373.399573] plane_wm level 5 cursor = 0 > [ 373.399578] plane_wm level 6 plane 0 = 2147582044 > [ 373.399591] plane_wm level 6 plane 1 = 0 > [ 373.399596] plane_wm level 6 cursor = 0 > [ 373.399602] plane_wm level 7 plane 0 = 2147598443 > [ 373.399607] plane_wm level 7 plane 1 = 0 > [ 373.399612] plane_wm level 7 cursor = 0 > [ 373.399617] wm_trans plane 0 = 0 > [ 373.399623] wm_trans plane 1 = 0 > [ 373.399627] wm_trans cursor = 0 > [ 373.399638] CRTC crtc-1 pipe B > [ 373.399642] clean > [ 373.399646] CRTC crtc-2 pipe C > [ 373.399650] clean > > The diff between those two dumps was: > > --- a.txt 2016-02-22 18:56:32.613058614 -0800 > +++ b.txt 2016-02-22 18:56:49.219079057 -0800 > @@ -3,10 +3,10 @@ > wm_linetime = 121 > plane_wm level 0 plane 0 = 2147500036 > plane_wm level 0 plane 1 = 0 > - plane_wm level 0 cursor = 2147500036 > + plane_wm level 0 cursor = 16388 > plane_wm level 1 plane 0 = 2147516439 > plane_wm level 1 plane 1 = 0 > - plane_wm level 1 cursor = 2147516439 > + plane_wm level 1 cursor = 32791 > plane_wm level 2 plane 0 = 2147516448 > plane_wm level 2 plane 1 = 0 > plane_wm level 2 cursor = 0 > > > The code that generated this is attached. > > Is the fix from Matt that you mentioned this one: > > commit e2e407dc093f530b771ee8bf8fe1be41e3cea8b3 > Author: Matt Roper <matthew.d.roper@xxxxxxxxx> > Date: Mon Feb 8 11:05:28 2016 -0800 > > drm/i915: Pretend cursor is always on for ILK-style WM calculations (v2) > > On brief inspection, it doesn't look like that patch will have any > effect on Skylake. > Re-ping. This is still broken AFAICT, and it's also not fixed in drm-intel-nightly. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
