hw/arm/virt: Add a user option to disallow ITS instantiation

In 2.9 ITS will block save/restore and migration use cases. As such,
let's introduce a user option that allows to turn its instantiation
off, along with GICv3. With the "its" option turned false, migration
will be possible, obviously at the expense of MSI support (with GICv3).

Signed-off-by: Eric Auger <[email protected]>
Message-id: 1487681108[email protected]
Reviewed-by: Peter Maydell <[email protected]>
Signed-off-by: Peter Maydell <[email protected]>

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 0c270b8919de078631fe5ec44236d40dc70cc3f7..5f62a0321e5b65112da95616f498057da42c901f 100644 (file)
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -535,7 +535,6 @@ static void create_v2m(VirtMachineState *vms, qemu_irq *pic)
 static void create_gic(VirtMachineState *vms, qemu_irq *pic)
 {
     /* We create a standalone GIC */
-    VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(vms);
     DeviceState *gicdev;
     SysBusDevice *gicbusdev;
     const char *gictype;
@@ -605,7 +604,7 @@ static void create_gic(VirtMachineState *vms, qemu_irq *pic)
 
     fdt_add_gic_node(vms);
 
-    if (type == 3 && !vmc->no_its) {
+    if (type == 3 && vms->its) {
         create_its(vms, gicdev);
     } else if (type == 2) {
         create_v2m(vms, pic);
@@ -1481,6 +1480,20 @@ static void virt_set_highmem(Object *obj, bool value, Error **errp)
     vms->highmem = value;
 }
 
+static bool virt_get_its(Object *obj, Error **errp)
+{
+    VirtMachineState *vms = VIRT_MACHINE(obj);
+
+    return vms->its;
+}
+
+static void virt_set_its(Object *obj, bool value, Error **errp)
+{
+    VirtMachineState *vms = VIRT_MACHINE(obj);
+
+    vms->its = value;
+}
+
 static char *virt_get_gic_version(Object *obj, Error **errp)
 {
     VirtMachineState *vms = VIRT_MACHINE(obj);
@@ -1541,6 +1554,7 @@ type_init(machvirt_machine_init);
 static void virt_2_9_instance_init(Object *obj)
 {
     VirtMachineState *vms = VIRT_MACHINE(obj);
+    VirtMachineClass *vmc = VIRT_MACHINE_GET_CLASS(vms);
 
     /* EL3 is disabled by default on virt: this makes us consistent
      * between KVM and TCG for this board, and it also allows us to
@@ -1580,6 +1594,19 @@ static void virt_2_9_instance_init(Object *obj)
                                     "Set GIC version. "
                                     "Valid values are 2, 3 and host", NULL);
 
+    if (vmc->no_its) {
+        vms->its = false;
+    } else {
+        /* Default allows ITS instantiation */
+        vms->its = true;
+        object_property_add_bool(obj, "its", virt_get_its,
+                                 virt_set_its, NULL);
+        object_property_set_description(obj, "its",
+                                        "Set on/off to enable/disable "
+                                        "ITS instantiation",
+                                        NULL);
+    }
+
     vms->memmap = a15memmap;
     vms->irqmap = a15irqmap;
 }

diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index 58ce74e0e5836e6df09c24d9ad4d40a887352fdd..33b0ff3892a3254f05e07f0091926112739e5cb2 100644 (file)
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -93,6 +93,7 @@ typedef struct {
     FWCfgState *fw_cfg;
     bool secure;
     bool highmem;
+    bool its;
     bool virt;
     int32_t gic_version;
     struct arm_boot_info bootinfo;