drm/i915/skl: Ensure HW is powered during DDB HW state readout
The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Spotted-by: Mika Kuoppala <mika.kuoppala@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93441
CC: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455719489-3008-1-git-send-email-imre.deak@intel.com
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index b63cdb2..347d4df 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2851,7 +2851,10 @@
memset(ddb, 0, sizeof(*ddb));
for_each_pipe(dev_priv, pipe) {
- if (!intel_display_power_is_enabled(dev_priv, POWER_DOMAIN_PIPE(pipe)))
+ enum intel_display_power_domain power_domain;
+
+ power_domain = POWER_DOMAIN_PIPE(pipe);
+ if (!intel_display_power_get_if_enabled(dev_priv, power_domain))
continue;
for_each_plane(dev_priv, pipe, plane) {
@@ -2863,6 +2866,8 @@
val = I915_READ(CUR_BUF_CFG(pipe));
skl_ddb_entry_init_from_hw(&ddb->plane[pipe][PLANE_CURSOR],
val);
+
+ intel_display_power_put(dev_priv, power_domain);
}
}