On Thu, Sep 18, 2014 at 06:51:50PM +0530, deepak.s@xxxxxxxxxxxxxxx wrote: > From: Deepak S <deepak.s@xxxxxxxxxxxxxxx> > > Based on the HW team inputs. We can should not wait for the old ack, > Waiting for old ack might fail, when other forcewake came before the > present one is desserted. > > for example, if forcewake bit 0 was set and before it could get cleared > forcewake bit 1 got set, HW eventually clear bit 0, when the bit 1 > is cleared. i.e, bit 1 is still sent then forcewake bit 0 will still be > set. > > Signed-off-by: Deepak S <deepak.s@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/i915/intel_uncore.c | 10 ---------- > 1 file changed, 10 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c > index 918b761..bcb0806 100644 > --- a/drivers/gpu/drm/i915/intel_uncore.c > +++ b/drivers/gpu/drm/i915/intel_uncore.c > @@ -196,11 +196,6 @@ static void __vlv_force_wake_get(struct drm_i915_private *dev_priv, > { > /* Check for Render Engine */ > if (FORCEWAKE_RENDER & fw_engine) { > - if (wait_for_atomic((__raw_i915_read32(dev_priv, > - FORCEWAKE_ACK_VLV) & > - FORCEWAKE_KERNEL) == 0, > - FORCEWAKE_ACK_TIMEOUT_MS)) > - DRM_ERROR("Timed out: Render forcewake old ack to clear.\n"); > Can we have a comment here? Something like this perhaps: /* * WaRsDontPollForAckOnClearingFWBits:vlv * Hardware clears ack bits lazily (only when all ack * bits become 0) so don't poll for individiual ack * bits to be clear here. */ Apart from that: Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > __raw_i915_write32(dev_priv, FORCEWAKE_VLV, > _MASKED_BIT_ENABLE(FORCEWAKE_KERNEL)); > @@ -214,11 +209,6 @@ static void __vlv_force_wake_get(struct drm_i915_private *dev_priv, > > /* Check for Media Engine */ > if (FORCEWAKE_MEDIA & fw_engine) { > - if (wait_for_atomic((__raw_i915_read32(dev_priv, > - FORCEWAKE_ACK_MEDIA_VLV) & > - FORCEWAKE_KERNEL) == 0, > - FORCEWAKE_ACK_TIMEOUT_MS)) > - DRM_ERROR("Timed out: Media forcewake old ack to clear.\n"); > > __raw_i915_write32(dev_priv, FORCEWAKE_MEDIA_VLV, > _MASKED_BIT_ENABLE(FORCEWAKE_KERNEL)); > -- > 1.9.1 > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Ville Syrjälä Intel OTC _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx