[Intel-gfx] [PATCH v3] drm/i915: Verify power domains after enabling them

[Chris Wilson]

Quoting Imre Deak (2018-08-17 15:58:37)
> After
> commit 2cd9a689e97b ("drm/i915: Refactor intel_display_set_init_power() logic")
> it makes more sense to check the power domain/well refcounts after
> enabling the power domains functionality. Before that it's guaranteed
> that most power wells (in the INIT domain) will have a reference held,
> so not an interesting state.
> 
> While at it also add the check after the init_hw/fini_hw, disable and
> suspend/resume steps. Make the test optional on a Kconfig option since
> it may add substantial overhead: on VLV/CHV the corresponding PUNIT reg
> access for each power well may take up to 20ms.
> 
> v2:
> - Add the state check to more spots. (Chris)
> 
> v3:
> - During suspend check the state before deiniting display core.
>   Afterwards DC states are disabled (and so the dc_off power well is
>   enabled) even though we don't hold a reference on it.
> - Do the test conditionally based on a new Kconfig option. (Chris)
> 
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Signed-off-by: Imre Deak <imre.deak at intel.com>
> Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk> (v2)

After cowardly waiting for CI to confirm the suspend state test was in
the right spot,
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>

Could you add

@@ -1318,6 +1319,8 @@  static void i915_welcome_messages(struct drm_i915_private *dev_priv)
 		DRM_INFO("DRM_I915_DEBUG enabled\n");
 	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM))
 		DRM_INFO("DRM_I915_DEBUG_GEM enabled\n");
+	if (IS_ENABLED(CONFIG_DRM_I915_DEBUG_RUNTIME_PM))
+		DRM_INFO("DRM_I915_DEBUG_RUNTIME_PM enabled\n");
 }

before pushing?
-Chris