From b10f1b20171945b49988b2b1fe68cb312cc36d32 Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Thu, 22 Oct 2015 13:56:34 +0200 Subject: [PATCH] drm/i915/skl: Prevent unclaimed register writes on skylake. I'm getting unclaimed register writes when checking the WM registers after the crtc is disabled. So I would imagine those are guarded by the crtc power well. Fix this by not reading out wm state when the power well is off. Cc: stable@vger.kernel.org # v4.3 Signed-off-by: Maarten Lankhorst Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92181 Reviewed-by: Daniel Vetter Signed-off-by: Jani Nikula --- drivers/gpu/drm/i915/intel_pm.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 80175a38a875..d52a15df6917 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -2818,7 +2818,12 @@ void skl_ddb_get_hw_state(struct drm_i915_private *dev_priv, int plane; u32 val; + memset(ddb, 0, sizeof(*ddb)); + for_each_pipe(dev_priv, pipe) { + if (!intel_display_power_is_enabled(dev_priv, POWER_DOMAIN_PIPE(pipe))) + continue; + for_each_plane(dev_priv, pipe, plane) { val = I915_READ(PLANE_BUF_CFG(pipe, plane)); skl_ddb_entry_init_from_hw(&ddb->plane[pipe][plane], -- 2.20.1