On Sat, 2013-12-14 at 20:38 -0200, Rodrigo Vivi wrote: > From: Imre Deak <imre.d...@intel.com> > > At least on my VLV stepping VGA detection doesn't work in certain cases. > One such case is when all pipes are off and VGA is plugged in. Another > case reported by Joonas Lahtinen (also on the same stepping) is booting > with VGA disconnected where we incorrectly report that VGA is connected. > At least in the first case writing the FORCE bit in the ADPA reg will > get stuck, i.e. the detection never completes. > > Both cases seem to be solved by disabling DPIO clock gating based on the > PSR state. As I haven't found any trace that this would be a known > issue, I can only speculate that both the DPIO HW block and the HW > block responsible for VGA detection uses the same clock source which gets > gated even though PSR is inactive. > > I haven't measured if and how this change affects our power savings. > > Reported-by: Joonas Lahtinen <joonas.lahti...@linux.intel.com> > Signed-off-by: Imre Deak <imre.d...@intel.com> > Signed-off-by: Rodrigo Vivi <rodrigo.v...@gmail.com>
Please ignore this, I'll send a v2. > --- > drivers/gpu/drm/i915/i915_reg.h | 3 +++ > drivers/gpu/drm/i915/intel_pm.c | 5 +++++ > 2 files changed, 8 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h > index f1eece4..726c3ce 100644 > --- a/drivers/gpu/drm/i915/i915_reg.h > +++ b/drivers/gpu/drm/i915/i915_reg.h > @@ -1451,6 +1451,9 @@ > # define I965_FT_CLOCK_GATE_DISABLE (1 << 1) > # define I965_DM_CLOCK_GATE_DISABLE (1 << 0) > > +#define DPPSR_CGDIS_VLV (dev_priv->info->display_mmio_offset > + 0x6204) > +# define DPIOUNIT_PSR_CLOCK_GATING_DISABLE (1 << 6) > + > #define RENCLK_GATE_D2 0x6208 > #define VF_UNIT_CLOCK_GATE_DISABLE (1 << 9) > #define GS_UNIT_CLOCK_GATE_DISABLE (1 << 7) > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c > index 465304a..4208065 100644 > --- a/drivers/gpu/drm/i915/intel_pm.c > +++ b/drivers/gpu/drm/i915/intel_pm.c > @@ -5438,6 +5438,11 @@ static void valleyview_init_clock_gating(struct > drm_device *dev) > > I915_WRITE(DSPCLK_GATE_D, VRHUNIT_CLOCK_GATE_DISABLE); > > + /* Wa to make VGA hotplug and manual detection work. */ > + val = I915_READ(DPPSR_CGDIS_VLV); > + val |= DPIOUNIT_PSR_CLOCK_GATING_DISABLE; > + I915_WRITE(DPIOUNIT_PSR_CLOCK_GATING_DISABLE, val); > + > /* WaDisableEarlyCull:vlv */ > I915_WRITE(_3D_CHICKEN3, > _MASKED_BIT_ENABLE(_3D_CHICKEN_SF_DISABLE_OBJEND_CULL)); _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
