drm/i915: fix display power sw state reporting

Atm, we refcount both power domains and power wells and
intel_display_power_enabled_sw() returns the power domain refcount. What
the callers are really interested in though is the sw state of the
underlying power wells. Due to this we will report incorrectly that a
given power domain is off if its power wells were enabled via another
power domain, for example POWER_DOMAIN_INIT which enables all power
wells.

As a fix return instead the state based on the refcount of all power
wells included in the passed in power domain.

References: https://bugs.freedesktop.org/show_bug.cgi?id=79505
References: https://bugs.freedesktop.org/show_bug.cgi?id=79038
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 16 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index f6fd86a17174..8bbd4f910663 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -5572,10 +5572,25 @@ bool intel_display_power_enabled_sw(struct drm_i915_private *dev_priv,
                                     enum intel_display_power_domain domain)
 {
         struct i915_power_domains *power_domains;
+        struct i915_power_well *power_well;
+        bool is_enabled;
+        int i;
+
+        if (dev_priv->pm.suspended)
+                return false;
 
         power_domains = &dev_priv->power_domains;
+        is_enabled = true;
+        for_each_power_well_rev(i, power_well, BIT(domain), power_domains) {
+                if (power_well->always_on)
+                        continue;
 
-        return power_domains->domain_use_count[domain];
+                if (!power_well->count) {
+                        is_enabled = false;
+                        break;
+                }
+        }
+        return is_enabled;
 }
 
 bool intel_display_power_enabled(struct drm_i915_private *dev_priv,