[PATCH 3/3] drm/i915: Move the tracking of dpms_mode down into crtc enable/disable

[Chris Wilson <chris@chris-wilson.co.uk>]

As we failed to update the dpms_mode after modeset, where it is presumed
to have been changed to DRM_MODE_DPMS_ON by the upper layers the dpms state
on the crtc became inconsistent with its actual active state. This
notably confused code and left the pipe active when it was meant to be
disabled, leading to PGTBL_ER if the fb was subsequently moved.

As we use the dpms_mode state for restoring the crtc after load-detection,
we can not simply remove it in favour of simply using the active state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/intel_display.c |   20 ++++++++++++++++++--
 1 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 78c38e2..e7822a6 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2904,6 +2904,8 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc)
 	intel_crtc_load_lut(crtc);
 	intel_update_fbc(dev);
 	intel_crtc_update_cursor(crtc, true);
+
+	intel_crtc->dpms_mode = DRM_MODE_DPMS_ON;
 }
 
 static void ironlake_crtc_disable(struct drm_crtc *crtc)
@@ -3000,6 +3002,8 @@ static void ironlake_crtc_disable(struct drm_crtc *crtc)
 	intel_update_watermarks(dev);
 	intel_update_fbc(dev);
 	intel_clear_scanline_wait(dev);
+
+	intel_crtc->dpms_mode = DRM_MODE_DPMS_OFF;
 }
 
 static void ironlake_crtc_dpms(struct drm_crtc *crtc, int mode)
@@ -3052,6 +3056,9 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
 	int pipe = intel_crtc->pipe;
 	int plane = intel_crtc->plane;
 
+	DRM_DEBUG_KMS("[CRTC:%d] active: %d\n",
+		      crtc->base.id, intel_crtc->active);
+
 	if (intel_crtc->active)
 		return;
 
@@ -3068,6 +3075,8 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
 	/* Give the overlay scaler a chance to enable if it's on this pipe */
 	intel_crtc_dpms_overlay(intel_crtc, true);
 	intel_crtc_update_cursor(crtc, true);
+
+	intel_crtc->dpms_mode = DRM_MODE_DPMS_ON;
 }
 
 static void i9xx_crtc_disable(struct drm_crtc *crtc)
@@ -3078,6 +3087,9 @@ static void i9xx_crtc_disable(struct drm_crtc *crtc)
 	int pipe = intel_crtc->pipe;
 	int plane = intel_crtc->plane;
 
+	DRM_DEBUG_KMS("[CRTC:%d] active: %d\n",
+		      crtc->base.id, intel_crtc->active);
+
 	if (!intel_crtc->active)
 		return;
 
@@ -3099,6 +3111,8 @@ static void i9xx_crtc_disable(struct drm_crtc *crtc)
 	intel_update_fbc(dev);
 	intel_update_watermarks(dev);
 	intel_clear_scanline_wait(dev);
+
+	intel_crtc->dpms_mode = DRM_MODE_DPMS_OFF;
 }
 
 static void i9xx_crtc_dpms(struct drm_crtc *crtc, int mode)
@@ -3130,11 +3144,13 @@ static void intel_crtc_dpms(struct drm_crtc *crtc, int mode)
 	int pipe = intel_crtc->pipe;
 	bool enabled;
 
+	DRM_DEBUG_KMS("[CRTC:%d] current dpms %d, new %d\n",
+		      crtc->base.id,
+		      intel_crtc->dpms_mode, mode);
+
 	if (intel_crtc->dpms_mode == mode)
 		return;
 
-	intel_crtc->dpms_mode = mode;
-
 	dev_priv->display.dpms(crtc, mode);
 
 	if (!dev->primary->master)
-- 
1.7.4.1