drm/nvc0/disp: fix regression in vblank semaphore release

Signed-off-by: Kelly Doran <kel.p.doran@gmail.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/core/engine/disp/nv50.c

@@ -22,6 +22,8 @@
  * Authors: Ben Skeggs
  */
 
+#include <subdev/bar.h>
+
 #include <engine/software.h>
 #include <engine/disp.h>
 
@@ -37,6 +39,7 @@ nv50_disp_sclass[] = {
 static void
 nv50_disp_intr_vblank(struct nv50_disp_priv *priv, int crtc)
 {
+	struct nouveau_bar *bar = nouveau_bar(priv);
 	struct nouveau_disp *disp = &priv->base;
 	struct nouveau_software_chan *chan, *temp;
 	unsigned long flags;
@@ -46,18 +49,19 @@ nv50_disp_intr_vblank(struct nv50_disp_priv *priv, int crtc)
 		if (chan->vblank.crtc != crtc)
 			continue;
 
-		nv_wr32(priv, 0x001704, chan->vblank.channel);
-		nv_wr32(priv, 0x001710, 0x80000000 | chan->vblank.ctxdma);
-
 		if (nv_device(priv)->chipset == 0x50) {
+			nv_wr32(priv, 0x001704, chan->vblank.channel);
+			nv_wr32(priv, 0x001710, 0x80000000 | chan->vblank.ctxdma);
+			bar->flush(bar);
 			nv_wr32(priv, 0x001570, chan->vblank.offset);
 			nv_wr32(priv, 0x001574, chan->vblank.value);
 		} else {
-			if (nv_device(priv)->chipset >= 0xc0) {
-				nv_wr32(priv, 0x06000c,
-					upper_32_bits(chan->vblank.offset));
-			}
-			nv_wr32(priv, 0x060010, chan->vblank.offset);
+			nv_wr32(priv, 0x001718, 0x80000000 | chan->vblank.channel);
+			bar->flush(bar);
+			nv_wr32(priv, 0x06000c,
+				upper_32_bits(chan->vblank.offset));
+			nv_wr32(priv, 0x060010,
+				lower_32_bits(chan->vblank.offset));
 			nv_wr32(priv, 0x060014, chan->vblank.value);
 		}