drm/nv17-50: restore fence buffer on resume

Since commit 5e120f6e4b3f35b741c5445dfc755f50128c3c44 "drm/nouveau/fence:
convert to exec engine, and improve channel sync" nouveau fence sync
implementation for nv17-50 and nvc0+ started to rely on state of fence buffer
left by previous sync operation. But as pinned bo's (where fence state is
stored) are not saved+restored across suspend/resume, we need to do it
manually.

nvc0+ was fixed by commit d6ba6d215a538a58f0f0026f0961b0b9125e8042
"drm/nvc0/fence: restore pre-suspend fence buffer context on resume".

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=50121

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/nouveau/nouveau_fence.h

@@ -60,6 +60,7 @@ u32  nv10_fence_read(struct nouveau_channel *);
 void nv10_fence_context_del(struct nouveau_channel *);
 void nv10_fence_destroy(struct nouveau_drm *);
 int  nv10_fence_create(struct nouveau_drm *);
+void nv17_fence_resume(struct nouveau_drm *drm);
 
 int nv50_fence_create(struct nouveau_drm *);
 int nv84_fence_create(struct nouveau_drm *);

drivers/gpu/drm/nouveau/nv10_fence.c

@@ -162,6 +162,13 @@ nv10_fence_destroy(struct nouveau_drm *drm)
 	kfree(priv);
 }
 
+void nv17_fence_resume(struct nouveau_drm *drm)
+{
+	struct nv10_fence_priv *priv = drm->fence;
+
+	nouveau_bo_wr32(priv->bo, 0, priv->sequence);
+}
+
 int
 nv10_fence_create(struct nouveau_drm *drm)
 {
@@ -197,6 +204,7 @@ nv10_fence_create(struct nouveau_drm *drm)
 		if (ret == 0) {
 			nouveau_bo_wr32(priv->bo, 0x000, 0x00000000);
 			priv->base.sync = nv17_fence_sync;
+			priv->base.resume = nv17_fence_resume;
 		}
 	}
 

drivers/gpu/drm/nouveau/nv50_fence.c

@@ -122,6 +122,7 @@ nv50_fence_create(struct nouveau_drm *drm)
 	if (ret == 0) {
 		nouveau_bo_wr32(priv->bo, 0x000, 0x00000000);
 		priv->base.sync = nv17_fence_sync;
+		priv->base.resume = nv17_fence_resume;
 	}
 
 	if (ret)