drm/nouveau/fifo/g84-: ack non-stall interrupt before handling it

Closes a very unlikely race that can occur if another NonStallInterrupt
method passes between checking fences and acking the previous interrupt.

With this change, the interrupt will re-fire under such conditions.

Tested-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/core/engine/fifo/nv04.c b/drivers/gpu/drm/nouveau/core/engine/fifo/nv04.c
index 5ae6a43..1931057 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/engine/fifo/nv04.c
+++ b/drivers/gpu/drm/nouveau/core/engine/fifo/nv04.c
@@ -551,8 +551,8 @@ nv04_fifo_intr(struct nouveau_subdev *subdev)
                        }
 
                        if (status & 0x40000000) {
-                               nouveau_fifo_uevent(&priv->base);
                                nv_wr32(priv, 0x002100, 0x40000000);
+                               nouveau_fifo_uevent(&priv->base);
                                status &= ~0x40000000;
                        }
                }

diff --git a/drivers/gpu/drm/nouveau/core/engine/fifo/nvc0.c b/drivers/gpu/drm/nouveau/core/engine/fifo/nvc0.c
index 1fe1f8f..074d434 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/engine/fifo/nvc0.c
+++ b/drivers/gpu/drm/nouveau/core/engine/fifo/nvc0.c
@@ -740,6 +740,8 @@ nvc0_fifo_intr_engine_unit(struct nvc0_fifo_priv *priv, int engn)
        u32 inte = nv_rd32(priv, 0x002628);
        u32 unkn;
 
+       nv_wr32(priv, 0x0025a8 + (engn * 0x04), intr);
+
        for (unkn = 0; unkn < 8; unkn++) {
                u32 ints = (intr >> (unkn * 0x04)) & inte;
                if (ints & 0x1) {
@@ -751,8 +753,6 @@ nvc0_fifo_intr_engine_unit(struct nvc0_fifo_priv *priv, int engn)
                        nv_mask(priv, 0x002628, ints, 0);
                }
        }
-
-       nv_wr32(priv, 0x0025a8 + (engn * 0x04), intr);
 }
 
 static void

diff --git a/drivers/gpu/drm/nouveau/core/engine/fifo/nve0.c b/drivers/gpu/drm/nouveau/core/engine/fifo/nve0.c
index d2f0fd3..f8734eb 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/engine/fifo/nve0.c
+++ b/drivers/gpu/drm/nouveau/core/engine/fifo/nve0.c
@@ -952,8 +952,8 @@ nve0_fifo_intr(struct nouveau_subdev *subdev)
        }
 
        if (stat & 0x80000000) {
-               nve0_fifo_intr_engine(priv);
                nv_wr32(priv, 0x002100, 0x80000000);
+               nve0_fifo_intr_engine(priv);
                stat &= ~0x80000000;
        }