spapr: split the IRQ allocation sequence

Today, when a device requests for IRQ number in a sPAPR machine, the
spapr_irq_alloc() routine first scans the ICSState status array to
find an empty slot and then performs the assignement of the selected
numbers. Split this sequence in two distinct routines : spapr_irq_find()
for lookups and spapr_irq_claim() for claiming the IRQ numbers.

This will ease the introduction of a static layout of IRQ numbers.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 9 insertions, 1 deletions

diff --git a/hw/ppc/spapr_vio.c b/hw/ppc/spapr_vio.c
index 4555c648a8..daf85130b5 100644
--- a/hw/ppc/spapr_vio.c
+++ b/hw/ppc/spapr_vio.c
@@ -475,7 +475,15 @@ static void spapr_vio_busdev_realize(DeviceState *qdev, Error **errp)
         dev->qdev.id = id;
     }
 
-    dev->irq = spapr_irq_alloc(spapr, dev->irq, false, &local_err);
+    if (!dev->irq) {
+        dev->irq = spapr_irq_findone(spapr, &local_err);
+        if (local_err) {
+            error_propagate(errp, local_err);
+            return;
+        }
+    }
+
+    spapr_irq_claim(spapr, dev->irq, false, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         return;