A couple of fixes (based mostly on stuff from upstream) to stop

breaking vblanks over suspend.

Firstly, when we turn off the irq, wait up anyone waiting on vblanks,
and prepare for the fact that interrupts are going off.

Secondly, only reduce the refcount for vblanks over modeset if they were
actually turned on.

Fixes gl apps running while you suspend an x40 (as in they still work
when it comes back).

1 files changed, 24 insertions, 9 deletions

diff --git a/sys/dev/pci/drm/drm_irq.c b/sys/dev/pci/drm/drm_irq.c
index ba9d1b8f82d..50fa58d826b 100644
--- a/sys/dev/pci/drm/drm_irq.c
+++ b/sys/dev/pci/drm/drm_irq.c
@@ -88,6 +88,7 @@ err:
 int
 drm_irq_uninstall(struct drm_device *dev)
 {
+	int i;
 
 	DRM_LOCK();
 	if (!dev->irq_enabled) {
@@ -98,6 +99,20 @@ drm_irq_uninstall(struct drm_device *dev)
 	dev->irq_enabled = 0;
 	DRM_UNLOCK();
 
+	/*
+	 * Ick. we're about to turn of vblanks, so make sure anyone waiting
+	 * on them gets woken up. Also make sure we update state correctly
+	 * so that we can continue refcounting correctly.
+	 */
+	mtx_enter(&dev->vbl_lock);
+	for (i = 0; i < dev->num_crtcs; i++) {
+		wakeup(&dev->vblank[i]);
+		dev->vblank[i].vbl_enabled = 0;
+		dev->vblank[i].last_vblank =
+		    dev->driver->get_vblank_counter(dev, i);
+	}
+	mtx_leave(&dev->vbl_lock);
+
 	DRM_DEBUG("irq=%d\n", dev->irq);
 
 	dev->driver->irq_uninstall(dev);
@@ -238,9 +253,6 @@ drm_vblank_get(struct drm_device *dev, int crtc)
 void
 drm_vblank_put(struct drm_device *dev, int crtc)
 {
-	if (dev->irq_enabled == 0)
-		return;
-
 	mtx_enter(&dev->vbl_lock);
 	/* Last user schedules interrupt disable */
 	atomic_dec(&dev->vblank[crtc].vbl_refcount);
@@ -274,18 +286,20 @@ drm_modeset_ctl(struct drm_device *dev, void *data, struct drm_file *file_priv)
 	case _DRM_PRE_MODESET:
 		if (dev->vblank[crtc].vbl_inmodeset == 0) {
 			mtx_enter(&dev->vbl_lock);
-			dev->vblank[crtc].vbl_inmodeset = 1;
+			dev->vblank[crtc].vbl_inmodeset = 0x1;
 			mtx_leave(&dev->vbl_lock);
-			drm_vblank_get(dev, crtc);
+			if (drm_vblank_get(dev, crtc) == 0)
+				dev->vblank[crtc].vbl_inmodeset |= 0x2;
 		}
 		break;
 	case _DRM_POST_MODESET:
 		if (dev->vblank[crtc].vbl_inmodeset) {
 			mtx_enter(&dev->vbl_lock);
 			dev->vblank_disable_allowed = 1;
-			dev->vblank[crtc].vbl_inmodeset = 0;
 			mtx_leave(&dev->vbl_lock);
-			drm_vblank_put(dev, crtc);
+			if (dev->vblank[crtc].vbl_inmodeset & 0x2)
+				drm_vblank_put(dev, crtc);
+			dev->vblank[crtc].vbl_inmodeset = 0;
 		}
 		break;
 	default:
@@ -332,8 +346,9 @@ drm_wait_vblank(struct drm_device *dev, void *data, struct drm_file *file_priv)
 		ret = EINVAL;
 	} else {
 		DRM_WAIT_ON(ret, &dev->vblank[crtc], &dev->vbl_lock, 3 * hz,
-		    "drmvblq", (drm_vblank_count(dev, crtc) -
-		    vblwait->request.sequence) <= (1 << 23));
+		    "drmvblq", ((drm_vblank_count(dev, crtc) -
+		    vblwait->request.sequence) <= (1 << 23)) ||
+		    dev->irq_enabled == 0);
 
 		if (ret != EINTR) {
 			struct timeval now;