drm/i915: fbdev restore mode needs to invalidate frontbuffer

This fbdev restore mode was another corner case that was now
calling frontbuffer flip and flush and making we miss
screen updates with PSR enabled.

So let's also add the invalidate hack here while we don't have
a reliable dirty fbdev op.

v2: As pointed by Paulo: removed seg fault risk, used fb_helper
    when possible and put brackets on if.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Testcase: igt/kms_fbcon_fbt/psr
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c
index 25ce7b62d4d5879541d680e7bd01bd73b9ed854a..33b3c9233eacbc7538686d440a879d40a1a91f07 100644 (file)
--- a/drivers/gpu/drm/i915/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/intel_fbdev.c
@@ -824,11 +824,20 @@ void intel_fbdev_restore_mode(struct drm_device *dev)
 {
        int ret;
        struct drm_i915_private *dev_priv = dev->dev_private;
+       struct intel_fbdev *ifbdev = dev_priv->fbdev;
+       struct drm_fb_helper *fb_helper;
 
-       if (!dev_priv->fbdev)
+       if (!ifbdev)
                return;
 
-       ret = drm_fb_helper_restore_fbdev_mode_unlocked(&dev_priv->fbdev->helper);
-       if (ret)
+       fb_helper = &ifbdev->helper;
+
+       ret = drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
+       if (ret) {
                DRM_DEBUG("failed to restore crtc mode\n");
+       } else {
+               mutex_lock(&fb_helper->dev->struct_mutex);
+               intel_fb_obj_invalidate(ifbdev->fb->obj, ORIGIN_GTT);
+               mutex_unlock(&fb_helper->dev->struct_mutex);
+       }
 }