On Tue, 2016-11-01 at 21:50 +0200, Jani Nikula wrote: > On Tue, 01 Nov 2016, "Pandiyan, Dhinakaran" <dhinakaran.pandiyan@xxxxxxxxx> wrote: > > On Tue, 2016-11-01 at 21:35 +0200, Jani Nikula wrote: > >> On Tue, 01 Nov 2016, Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx> wrote: > >> > According to BSpec, cdclk for BDW has to be not less than 432 MHz with DP > >> > audio enabled, port width x4, and link rate HBR2 (5.4 GHz). With cdclk less > >> > than 432 MHz, enabling audio leads to pipe FIFO underruns and displays > >> > cycling on/off. > >> > > >> > Let's apply this work around to GEN9 platforms too, as it fixes the same > >> > issue. > >> > >> I'm too tired to read bspec now, but is gen9 really the answer, or just > >> Skylake? > >> > >> > > > > Gen9, applies to BXT and KBL as well. > > I'll take your word for it, and with that, > > Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx> > > > Thanks for the review. > > > > -DK > > > >> > > >> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97907 > >> > Cc: stable@xxxxxxxxxxxxxxx > >> > Cc: Libin Yang <libin.yang@xxxxxxxxxxxxxxx> > >> > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx> > >> > --- > >> > drivers/gpu/drm/i915/intel_display.c | 6 ++++-- > >> > 1 file changed, 4 insertions(+), 2 deletions(-) > >> > > >> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c > >> > index 37483ee..c0ae147 100644 > >> > --- a/drivers/gpu/drm/i915/intel_display.c > >> > +++ b/drivers/gpu/drm/i915/intel_display.c > >> > @@ -10264,8 +10264,10 @@ static void bxt_modeset_commit_cdclk(struct drm_atomic_state *old_state) > >> > static int bdw_adjust_min_pipe_pixel_rate(struct intel_crtc_state *crtc_state, > >> > int pixel_rate) > >> > { > >> > + struct drm_device *dev = crtc_state->base.crtc->dev; > >> > >> Nitpick, I guess I'd make that > >> > >> struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev); > >> > >> but no big deal. > >> > >> > + > >> > /* pixel rate mustn't exceed 95% of cdclk with IPS on BDW */ > >> > - if (crtc_state->ips_enabled) > >> > + if (IS_BROADWELL(to_i915(dev)) && crtc_state->ips_enabled) > >> > pixel_rate = DIV_ROUND_UP(pixel_rate * 100, 95); > >> > > >> > /* BSpec says "Do not use DisplayPort with CDCLK less than > >> > @@ -10307,7 +10309,7 @@ static int ilk_max_pixel_rate(struct drm_atomic_state *state) > >> > > >> > pixel_rate = ilk_pipe_pixel_rate(crtc_state); > >> > > >> > - if (IS_BROADWELL(dev_priv)) > >> > + if (IS_BROADWELL(dev_priv) || IS_GEN9(dev_priv)) > >> > pixel_rate = bdw_adjust_min_pipe_pixel_rate(crtc_state, > >> > pixel_rate); > >> > > > ��.n��������+%������w��{.n�����������ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f