drm: Add a debug node for vblank state.

Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>

1 files changed, 9 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 1608f8dbfda0..724e505873cf 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -116,6 +116,9 @@ void drm_vblank_cleanup(struct drm_device *dev)
                  dev->num_crtcs, DRM_MEM_DRIVER);
         drm_free(dev->last_vblank, sizeof(*dev->last_vblank) * dev->num_crtcs,
                  DRM_MEM_DRIVER);
+        drm_free(dev->last_vblank_wait,
+                 sizeof(*dev->last_vblank_wait) * dev->num_crtcs,
+                 DRM_MEM_DRIVER);
         drm_free(dev->vblank_inmodeset, sizeof(*dev->vblank_inmodeset) *
                  dev->num_crtcs, DRM_MEM_DRIVER);
 
@@ -161,6 +164,11 @@ int drm_vblank_init(struct drm_device *dev, int num_crtcs)
         if (!dev->last_vblank)
                 goto err;
 
+        dev->last_vblank_wait = drm_calloc(num_crtcs, sizeof(u32),
+                                           DRM_MEM_DRIVER);
+        if (!dev->last_vblank_wait)
+                goto err;
+
         dev->vblank_inmodeset = drm_calloc(num_crtcs, sizeof(int),
                                          DRM_MEM_DRIVER);
         if (!dev->vblank_inmodeset)
@@ -642,6 +650,7 @@ int drm_wait_vblank(struct drm_device *dev, void *data,
         } else {
                 DRM_DEBUG("waiting on vblank count %d, crtc %d\n",
                           vblwait->request.sequence, crtc);
+                dev->last_vblank_wait[crtc] = vblwait->request.sequence;
                 DRM_WAIT_ON(ret, dev->vbl_queue[crtc], 3 * DRM_HZ,
                             ((drm_vblank_count(dev, crtc)
                               - vblwait->request.sequence) <= (1 << 23)));