drm/nouveau/mc: have single entry and exit points to the interrupt handler

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/core/subdev/mc/base.c b/drivers/gpu/drm/nouveau/core/subdev/mc/base.c
index be5bdee..f26fcbd 100644 (file)
--- a/drivers/gpu/drm/nouveau/core/subdev/mc/base.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/mc/base.c
@@ -31,29 +31,30 @@ nouveau_mc_intr(int irq, void *arg)
        struct nouveau_mc *pmc = arg;
        const struct nouveau_mc_intr *map = pmc->intr_map;
        struct nouveau_subdev *unit;
-       u32 stat, intr;
+       u32 intr, stat;
 
-       intr = stat = nv_rd32(pmc, 0x000100);
-       if (intr == 0xffffffff)
-               return IRQ_NONE;
-       while (stat && map->stat) {
-               if (stat & map->stat) {
-                       unit = nouveau_subdev(pmc, map->unit);
-                       if (unit && unit->intr)
-                               unit->intr(unit);
-                       intr &= ~map->stat;
-               }
-               map++;
-       }
+       intr = nv_rd32(pmc, 0x000100);
+       if (intr == 0xffffffff) /* likely fallen off the bus */
+               intr = 0x00000000;
 
-       if (pmc->use_msi)
-               nv_wr08(pmc, 0x088068, 0xff);
+       if ((stat = intr) != 0) {
+               while (map->stat) {
+                       if (intr & map->stat) {
+                               unit = nouveau_subdev(pmc, map->unit);
+                               if (unit && unit->intr)
+                                       unit->intr(unit);
+                               stat &= ~map->stat;
+                       }
+                       map++;
+               }
 
-       if (intr) {
-               nv_error(pmc, "unknown intr 0x%08x\n", stat);
+               if (pmc->use_msi)
+                       nv_wr08(pmc, 0x088068, 0xff);
+               if (stat)
+                       nv_error(pmc, "unknown intr 0x%08x\n", stat);
        }
 
-       return stat ? IRQ_HANDLED : IRQ_NONE;
+       return intr ? IRQ_HANDLED : IRQ_NONE;
 }
 
 int