Hi Art, Indeed my patch looks fishy and it's because this isn't the code I've tested the entire night :( The one that works simply disables lp1+ wm levels. Which is a bit an oversized hammer really. Do you have any ideas for w/a or smaller tricks I could try? I did try just blantantly multiplying wm levels a bit but that didn't help. At least not the few things I've tried. Still only seen this on snb thus far. Thanks, Daniel On Mon, Mar 2, 2015 at 8:39 PM, Runyan, Arthur J <arthur.j.runyan@xxxxxxxxx> wrote: > I think your ilk_wm_method2 is busted. Method 2 should always give more than one full line, making this 1 line redundant. > > > -----Original Message----- > From: Daniel Vetter [mailto:daniel.vetter@xxxxxxxx] > Sent: Monday, March 02, 2015 9:09 AM > To: Intel Graphics Development; Runyan, Arthur J > Cc: Daniel Vetter; Ville Syrjälä; Roper, Matthew D; Paulo Zanoni; Vetter, Daniel > Subject: Re: [PATCH] drm/i915: Fix big cursors on snb > > Forgotten to cc Art as fyi. > -Daniel > > On Mon, Mar 2, 2015 at 5:35 PM, Daniel Vetter <daniel.vetter@xxxxxxxx> wrote: >> My snb seemed somewhat unhappy with 256x256 cursors and failed all the >> relevant kms_cursor_crc subtests sporadically, including logging cpu >> fifo underruns. Smaller cursor work perfectly with a failure rate at >> least 1000x less (got bored after running tests for days). >> >> After some playing around with impressive hammers Ville suggested to >> increase the watermarks to at least cover a full cursor line. It seems >> to work thus far. This means that for lp wms we now required 1/4th of >> the fifo for 256 wide cursors, and much less on gen7+. Hence fetches >> should still be nice&big. Therefore I expect very little power impact >> and decided to just do this everywhere, even though I've only seen >> this on my snb laptop. Especially since Ville is thinking about >> similar changes for the gmch wm code. skl separate wm code and also >> completely new plane hw, so hopefully isn't affected. >> >> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> >> Cc: Matt Roper <matthew.d.roper@xxxxxxxxx> >> Cc: Paulo Zanoni <przanoni@xxxxxxxxx> >> Testcase: igt/kms_cursor_crc/*-256x256-* >> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> >> --- >> drivers/gpu/drm/i915/intel_pm.c | 17 ++++++++++++----- >> 1 file changed, 12 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c >> index 7dcb5b60600b..7e97a30bd6c0 100644 >> --- a/drivers/gpu/drm/i915/intel_pm.c >> +++ b/drivers/gpu/drm[Art] /i915/intel_pm.c >> @@ -1449,14 +1449,21 @@ static uint32_t ilk_compute_spr_wm(const struct ilk_pipe_wm_parameters *params, >> static uint32_t ilk_compute_cur_wm(const struct ilk_pipe_wm_parameters *params, >> uint32_t mem_value) >> { >> + uint32_t line_wm, method2; >> + >> if (!params->active || !params->cur.enabled) >> return 0; >> >> - return ilk_wm_method2(params->pixel_rate, >> - params->pipe_htotal, >> - params->cur.horiz_pixels, >> - params->cur.bytes_per_pixel, >> - mem_value); >> + /* HACK: Big cursors tend to underrun, load at least one line. */ >> + line_wm = params->cur.horiz_pixels * params->cur.bytes_per_pixel / 64; >> + >> + method2 = ilk_wm_method2(params->pixel_rate, >> + params->pipe_htotal, >> + params->cur.horiz_pixels, >> + params->cur.bytes_per_pixel, >> + mem_value); >> + >> + return max(line_wm, method2); >> } >> >> /* Only for WM_LP. */ >> -- >> 1.9.3 >> > > > > -- > Daniel Vetter > Software Engineer, Intel Corporation > +41 (0) 79 365 57 48 - http://blog.ffwll.ch -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
