1 files changed, 30 insertions, 7 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index a05ac2c91ba2..287b42c9d1a8 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3604,6 +3604,30 @@ static void intel_crtc_dpms_overlay(struct intel_crtc *intel_crtc, bool enable)
          */
 }
 
+/**
+ * i9xx_fixup_plane - ugly workaround for G45 to fire up the hardware
+ * cursor plane briefly if not already running after enabling the display
+ * plane.
+ * This workaround avoids occasional blank screens when self refresh is
+ * enabled.
+ */
+static void
+g4x_fixup_plane(struct drm_i915_private *dev_priv, enum pipe pipe)
+{
+        u32 cntl = I915_READ(CURCNTR(pipe));
+
+        if ((cntl & CURSOR_MODE) == 0) {
+                u32 fw_bcl_self = I915_READ(FW_BLC_SELF);
+
+                I915_WRITE(FW_BLC_SELF, fw_bcl_self & ~FW_BLC_SELF_EN);
+                I915_WRITE(CURCNTR(pipe), CURSOR_MODE_64_ARGB_AX);
+                intel_wait_for_vblank(dev_priv->dev, pipe);
+                I915_WRITE(CURCNTR(pipe), cntl);
+                I915_WRITE(CURBASE(pipe), I915_READ(CURBASE(pipe)));
+                I915_WRITE(FW_BLC_SELF, fw_bcl_self);
+        }
+}
+
 static void i9xx_crtc_enable(struct drm_crtc *crtc)
 {
         struct drm_device *dev = crtc->dev;
@@ -3629,6 +3653,8 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
 
         intel_enable_pipe(dev_priv, pipe, false);
         intel_enable_plane(dev_priv, plane, pipe);
+        if (IS_G4X(dev))
+                g4x_fixup_plane(dev_priv, pipe);
 
         intel_crtc_load_lut(crtc);
         intel_update_fbc(dev);
@@ -7256,8 +7282,8 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
 {
         struct drm_device *dev = crtc->dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
-        struct intel_framebuffer *intel_fb;
-        struct drm_i915_gem_object *obj;
+        struct drm_framebuffer *old_fb = crtc->fb;
+        struct drm_i915_gem_object *obj = to_intel_framebuffer(fb)->obj;
         struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
         struct intel_unpin_work *work;
         unsigned long flags;
@@ -7282,8 +7308,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
 
         work->event = event;
         work->crtc = crtc;
-        intel_fb = to_intel_framebuffer(crtc->fb);
-        work->old_fb_obj = intel_fb->obj;
+        work->old_fb_obj = to_intel_framebuffer(old_fb)->obj;
         INIT_WORK(&work->work, intel_unpin_work_fn);
 
         ret = drm_vblank_get(dev, intel_crtc->pipe);
@@ -7303,9 +7328,6 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
         intel_crtc->unpin_work = work;
         spin_unlock_irqrestore(&dev->event_lock, flags);
 
-        intel_fb = to_intel_framebuffer(fb);
-        obj = intel_fb->obj;
-
         if (atomic_read(&intel_crtc->unpin_work_count) >= 2)
                 flush_workqueue(dev_priv->wq);
 
@@ -7340,6 +7362,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc,
 
 cleanup_pending:
         atomic_dec(&intel_crtc->unpin_work_count);
+        crtc->fb = old_fb;
         drm_gem_object_unreference(&work->old_fb_obj->base);
         drm_gem_object_unreference(&obj->base);
         mutex_unlock(&dev->struct_mutex);