diff --git a/drivers/gpu/drm/nouveau/nvc0_fifo.c b/drivers/gpu/drm/nouveau/nvc0_fifo.c
index 7d85553d518c42ee5826c0cf516086cf01ce1534..cd39eb99f5b15b4aef3f9fa4d47967b7bf3f55f6 100644
--- a/drivers/gpu/drm/nouveau/nvc0_fifo.c
+++ b/drivers/gpu/drm/nouveau/nvc0_fifo.c
@@ -373,7 +373,8 @@ nvc0_fifo_isr_subfifo_intr(struct drm_device *dev, int unit)
 static void
 nvc0_fifo_isr(struct drm_device *dev)
 {
-	u32 stat = nv_rd32(dev, 0x002100);
+	u32 mask = nv_rd32(dev, 0x002140);
+	u32 stat = nv_rd32(dev, 0x002100) & mask;
 
 	if (stat & 0x00000100) {
 		NV_INFO(dev, "PFIFO: unknown status 0x00000100\n");
diff --git a/drivers/gpu/drm/nouveau/nve0_fifo.c b/drivers/gpu/drm/nouveau/nve0_fifo.c
index e98d144e6eb9df766fc458e03bdd35acef349ce4..281bece751b61eb091d2b6da73144dc9d2ddb5c5 100644
--- a/drivers/gpu/drm/nouveau/nve0_fifo.c
+++ b/drivers/gpu/drm/nouveau/nve0_fifo.c
@@ -345,7 +345,8 @@ nve0_fifo_isr_subfifo_intr(struct drm_device *dev, int unit)
 static void
 nve0_fifo_isr(struct drm_device *dev)
 {
-	u32 stat = nv_rd32(dev, 0x002100);
+	u32 mask = nv_rd32(dev, 0x002140);
+	u32 stat = nv_rd32(dev, 0x002100) & mask;
 
 	if (stat & 0x00000100) {
 		NV_INFO(dev, "PFIFO: unknown status 0x00000100\n");