[PATCH RFC v3 3/8] hw/arm/virt: Add a machine option to bypass iommu for primary bus

[Wang Xingang]

From: Xingang Wang <wangxingang5@huawei.com>

This add a bypass_iommu option for arm virt machine,
the option can be used in this manner:
qemu -machine virt,iommu=smmuv3,bypass_iommu=true

Signed-off-by: Xingang Wang <wangxingang5@huawei.com>
Signed-off-by: Jiahui Cen <cenjiahui@huawei.com>
---
 hw/arm/virt.c         | 26 ++++++++++++++++++++++++++
 include/hw/arm/virt.h |  1 +
 2 files changed, 27 insertions(+)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 9f01d9041b..0ce6167aab 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -1366,6 +1366,7 @@ static void create_pcie(VirtMachineState *vms)
     }
 
     pci = PCI_HOST_BRIDGE(dev);
+    pci->bypass_iommu = vms->bypass_iommu;
     vms->bus = pci->bus;
     if (vms->bus) {
         for (i = 0; i < nb_nics; i++) {
@@ -2319,6 +2320,21 @@ static void virt_set_iommu(Object *obj, const char 
*value, Error **errp)
     }
 }
 
+static bool virt_get_bypass_iommu(Object *obj, Error **errp)
+{
+    VirtMachineState *vms = VIRT_MACHINE(obj);
+
+    return vms->bypass_iommu;
+}
+
+static void virt_set_bypass_iommu(Object *obj, bool value,
+                                              Error **errp)
+{
+    VirtMachineState *vms = VIRT_MACHINE(obj);
+
+    vms->bypass_iommu = value;
+}
+
 static CpuInstanceProperties
 virt_cpu_index_to_props(MachineState *ms, unsigned cpu_index)
 {
@@ -2656,6 +2672,13 @@ static void virt_machine_class_init(ObjectClass *oc, 
void *data)
                                           "Set the IOMMU type. "
                                           "Valid values are none and smmuv3");
 
+    object_class_property_add_bool(oc, "bypass_iommu",
+                                   virt_get_bypass_iommu,
+                                   virt_set_bypass_iommu);
+    object_class_property_set_description(oc, "bypass_iommu",
+                                          "Set on/off to enable/disable "
+                                          "bypass_iommu for primary bus");
+
     object_class_property_add_bool(oc, "ras", virt_get_ras,
                                    virt_set_ras);
     object_class_property_set_description(oc, "ras",
@@ -2723,6 +2746,9 @@ static void virt_instance_init(Object *obj)
     /* Default disallows iommu instantiation */
     vms->iommu = VIRT_IOMMU_NONE;
 
+    /* The primary bus is attached to iommu by default */
+    vms->bypass_iommu = false;
+
     /* Default disallows RAS instantiation */
     vms->ras = false;
 
diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
index 921416f918..82bceadb82 100644
--- a/include/hw/arm/virt.h
+++ b/include/hw/arm/virt.h
@@ -147,6 +147,7 @@ struct VirtMachineState {
     OnOffAuto acpi;
     VirtGICType gic_version;
     VirtIOMMUType iommu;
+    bool bypass_iommu;
     VirtMSIControllerType msi_controller;
     uint16_t virtio_iommu_bdf;
     struct arm_boot_info bootinfo;
-- 
2.19.1