On la, 2015-12-19 at 09:58 +0000, Chris Wilson wrote: > Once all the preparations are complete, we are ready to write the > modesetting to the hardware. During this phase, we will be making > lots > of HW register access, so take a top level wakeref to prevent an > unwarranted rpm suspend cycle mid-commit. Lower level functions > should > be waking the individual power wells as required. > > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93439 I would separate here two things: The device level power flip-flopping you mention and the fix for the above bug. For the flip-flopping we could use what you suggest, perhaps by also avoiding waking up the device if nothing will change and everything will stay disabled. As for the fix I would go with what Ville suggested. By ensuring we keep an RPM reference we still allow for a display power domain reference to come and go in the middle of the HW readout. I went ahead and tried the following which got rid of the problem too, if people are ok with it I could convert the rest of the HW readout places accordingly and send out the patch. We can also get pm_runtime_get_if_in_use() into use once it's added, but it's not crucial for the fix. diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index 1f9a368..907377dc 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -1910,13 +1910,16 @@ bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector) enum transcoder cpu_transcoder; enum intel_display_power_domain power_domain; uint32_t tmp; + bool ret; power_domain = intel_display_port_power_domain(intel_encoder); - if (!intel_display_power_is_enabled(dev_priv, power_domain)) + if (!intel_display_power_get_if_enabled(dev_priv, power_domain)) return false; - if (!intel_encoder->get_hw_state(intel_encoder, &pipe)) - return false; + if (!intel_encoder->get_hw_state(intel_encoder, &pipe)) { + ret = false; + goto out; + } if (port == PORT_A) cpu_transcoder = TRANSCODER_EDP; @@ -1928,23 +1931,30 @@ bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector) switch (tmp & TRANS_DDI_MODE_SELECT_MASK) { case TRANS_DDI_MODE_SELECT_HDMI: case TRANS_DDI_MODE_SELECT_DVI: - return (type == DRM_MODE_CONNECTOR_HDMIA); + ret = type == DRM_MODE_CONNECTOR_HDMIA; + goto out; case TRANS_DDI_MODE_SELECT_DP_SST: - if (type == DRM_MODE_CONNECTOR_eDP) - return true; - return (type == DRM_MODE_CONNECTOR_DisplayPort); + ret = type == DRM_MODE_CONNECTOR_eDP || + type == DRM_MODE_CONNECTOR_DisplayPort; + goto out; case TRANS_DDI_MODE_SELECT_DP_MST: /* if the transcoder is in MST state then * connector isn't connected */ - return false; + ret = false; + goto out; case TRANS_DDI_MODE_SELECT_FDI: - return (type == DRM_MODE_CONNECTOR_VGA); + ret = type == DRM_MODE_CONNECTOR_VGA; + goto out; default: - return false; + ret = false; } +out: + intel_display_power_put(dev_priv, power_domain); + + return ret; } bool intel_ddi_get_hw_state(struct intel_encoder *encoder, diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 059b46e..3c84159 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1456,6 +1456,8 @@ bool __intel_display_power_is_enabled(struct drm_i915_private *dev_priv, enum intel_display_power_domain domain); void intel_display_power_get(struct drm_i915_private *dev_priv, enum intel_display_power_domain domain); +bool intel_display_power_get_if_enabled(struct drm_i915_private *dev_priv, + enum intel_display_power_domain domain); void intel_display_power_put(struct drm_i915_private *dev_priv, enum intel_display_power_domain domain); diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c index bbca527..6c4f170 100644 --- a/drivers/gpu/drm/i915/intel_runtime_pm.c +++ b/drivers/gpu/drm/i915/intel_runtime_pm.c @@ -1470,6 +1470,17 @@ void intel_display_power_get(struct drm_i915_private *dev_priv, mutex_unlock(&power_domains->lock); } +bool intel_display_power_get_if_enabled(struct drm_i915_private *dev_priv, + enum intel_display_power_domain domain) +{ + if (!intel_display_power_is_enabled(dev_priv, domain)) + return false; + + intel_display_power_get(dev_priv, domain); + + return true; +} + /** * intel_display_power_put - release a power domain reference * @dev_priv: i915 device instance --Imre > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > Cc: Imre Deak <imre.deak@xxxxxxxxx> > --- > drivers/gpu/drm/i915/intel_display.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/gpu/drm/i915/intel_display.c > b/drivers/gpu/drm/i915/intel_display.c > index abd2d2944022..60451c3932db 100644 > --- a/drivers/gpu/drm/i915/intel_display.c > +++ b/drivers/gpu/drm/i915/intel_display.c > @@ -13470,6 +13470,13 @@ static int intel_atomic_commit(struct > drm_device *dev, > drm_atomic_helper_swap_state(dev, state); > dev_priv->wm.config = to_intel_atomic_state(state)- > >wm_config; > > + /* Take a rpm wakeref for the duration of the commit. Lower > level > + * functions should be acquiring the power wells for their > own use, > + * we take this toplevel reference to prevent rpm suspend > cycles > + * mid-commit. > + */ > + intel_runtime_pm_get(dev_priv); > + > for_each_crtc_in_state(state, crtc, crtc_state, i) { > struct intel_crtc *intel_crtc = to_intel_crtc(crtc); > > @@ -13558,6 +13565,8 @@ static int intel_atomic_commit(struct > drm_device *dev, > if (any_ms) > intel_modeset_check_state(dev, state); > > + intel_runtime_pm_put(dev_priv); > + > drm_atomic_state_free(state); > > return 0; _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
