From 25eaa003bd186e415d94bf0191152f1cd7252d9a Mon Sep 17 00:00:00 2001 From: Imre Deak Date: Tue, 4 Mar 2014 19:23:06 +0200 Subject: [PATCH] drm/i915: sanity check power well sw state against hw state Suggested by Daniel. v2: - sanitize the state checking condition, the original was rather confusing (partly due to the unfortunate naming of i915.disable_power_well) (Ville) - simpler message+backtrace generation by using WARN instead of WARN_ON (Ville) - check if always-on power wells are truly on all the time Signed-off-by: Imre Deak Reviewed-by: Jesse Barnes Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_pm.c | 38 ++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 19591488fd2a..5b039ca13927 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -5411,6 +5411,29 @@ static bool i9xx_always_on_power_well_enabled(struct drm_i915_private *dev_priv, return true; } +static void check_power_well_state(struct drm_i915_private *dev_priv, + struct i915_power_well *power_well) +{ + bool enabled = power_well->ops->is_enabled(dev_priv, power_well); + + if (power_well->always_on || !i915.disable_power_well) { + if (!enabled) + goto mismatch; + + return; + } + + if (enabled != (power_well->count > 0)) + goto mismatch; + + return; + +mismatch: + WARN(1, "state mismatch for '%s' (always_on %d hw state %d use-count %d disable_power_well %d\n", + power_well->name, power_well->always_on, enabled, + power_well->count, i915.disable_power_well); +} + void intel_display_power_get(struct drm_i915_private *dev_priv, enum intel_display_power_domain domain) { @@ -5422,9 +5445,14 @@ void intel_display_power_get(struct drm_i915_private *dev_priv, mutex_lock(&power_domains->lock); - for_each_power_well(i, power_well, BIT(domain), power_domains) - if (!power_well->count++) + for_each_power_well(i, power_well, BIT(domain), power_domains) { + if (!power_well->count++) { + DRM_DEBUG_KMS("enabling %s\n", power_well->name); power_well->ops->enable(dev_priv, power_well); + } + + check_power_well_state(dev_priv, power_well); + } power_domains->domain_use_count[domain]++; @@ -5448,8 +5476,12 @@ void intel_display_power_put(struct drm_i915_private *dev_priv, for_each_power_well_rev(i, power_well, BIT(domain), power_domains) { WARN_ON(!power_well->count); - if (!--power_well->count && i915.disable_power_well) + if (!--power_well->count && i915.disable_power_well) { + DRM_DEBUG_KMS("disabling %s\n", power_well->name); power_well->ops->disable(dev_priv, power_well); + } + + check_power_well_state(dev_priv, power_well); } mutex_unlock(&power_domains->lock); -- 2.30.2