On Tue, 01 Oct 2024, Ville Syrjala <[email protected]> wrote: > From: Ville Syrjälä <[email protected]> > > Extract the i915gm/i945gm vblank irq C-state workaround to > separate functions. We'll need to reuse these in order to > guarantee timely CRC interrupt delivery as well. > > The irq.vblank_enabled count is currently protected by the > drm vblanl locks, so let's assert that the innermost of those
*vblank Reviewed-by: Jani Nikula <[email protected]> > is held, in anticipation of other callers. > > Signed-off-by: Ville Syrjälä <[email protected]> > --- > .../gpu/drm/i915/display/intel_display_irq.c | 34 +++++++++++++------ > 1 file changed, 24 insertions(+), 10 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.c > b/drivers/gpu/drm/i915/display/intel_display_irq.c > index 43a0b3565bc8..feeb3a29972a 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_irq.c > +++ b/drivers/gpu/drm/i915/display/intel_display_irq.c > @@ -1259,6 +1259,28 @@ void gen11_display_irq_handler(struct drm_i915_private > *i915) > enable_rpm_wakeref_asserts(&i915->runtime_pm); > } > > +static void i915gm_irq_cstate_wa_enable(struct drm_i915_private *i915) > +{ > + lockdep_assert_held(&i915->drm.vblank_time_lock); > + > + /* > + * Vblank interrupts fail to wake the device up from C2+. > + * Disabling render clock gating during C-states avoids > + * the problem. There is a small power cost so we do this > + * only when vblank interrupts are actually enabled. > + */ > + if (i915->display.irq.vblank_enabled++ == 0) > + intel_uncore_write(&i915->uncore, SCPD0, > _MASKED_BIT_ENABLE(CSTATE_RENDER_CLOCK_GATE_DISABLE)); > +} > + > +static void i915gm_irq_cstate_wa_disable(struct drm_i915_private *i915) > +{ > + lockdep_assert_held(&i915->drm.vblank_time_lock); > + > + if (--i915->display.irq.vblank_enabled == 0) > + intel_uncore_write(&i915->uncore, SCPD0, > _MASKED_BIT_DISABLE(CSTATE_RENDER_CLOCK_GATE_DISABLE)); > +} > + > int i8xx_enable_vblank(struct drm_crtc *crtc) > { > struct drm_i915_private *dev_priv = to_i915(crtc->dev); > @@ -1287,14 +1309,7 @@ int i915gm_enable_vblank(struct drm_crtc *crtc) > { > struct drm_i915_private *i915 = to_i915(crtc->dev); > > - /* > - * Vblank interrupts fail to wake the device up from C2+. > - * Disabling render clock gating during C-states avoids > - * the problem. There is a small power cost so we do this > - * only when vblank interrupts are actually enabled. > - */ > - if (i915->display.irq.vblank_enabled++ == 0) > - intel_uncore_write(&i915->uncore, SCPD0, > _MASKED_BIT_ENABLE(CSTATE_RENDER_CLOCK_GATE_DISABLE)); > + i915gm_irq_cstate_wa_enable(i915); > > return i8xx_enable_vblank(crtc); > } > @@ -1305,8 +1320,7 @@ void i915gm_disable_vblank(struct drm_crtc *crtc) > > i8xx_disable_vblank(crtc); > > - if (--i915->display.irq.vblank_enabled == 0) > - intel_uncore_write(&i915->uncore, SCPD0, > _MASKED_BIT_DISABLE(CSTATE_RENDER_CLOCK_GATE_DISABLE)); > + i915gm_irq_cstate_wa_disable(i915); > } > > int i965_enable_vblank(struct drm_crtc *crtc) -- Jani Nikula, Intel
