x86-iommu: introduce parent class

Introducing parent class for intel-iommu devices named "x86-iommu". This
is preparation work to abstract shared functionalities out from Intel
and AMD IOMMUs. Currently, only the parent class is introduced. It does
nothing yet.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/i386/Makefile.objs

@@ -2,7 +2,7 @@ obj-$(CONFIG_KVM) += kvm/
 obj-y += multiboot.o
 obj-y += pc.o pc_piix.o pc_q35.o
 obj-y += pc_sysfw.o
-obj-y += intel_iommu.o
+obj-y += x86-iommu.o intel_iommu.o
 obj-$(CONFIG_XEN) += ../xenpv/ xen/
 
 obj-y += kvmvapic.o

hw/i386/intel_iommu.c

@@ -2061,17 +2061,18 @@ static void vtd_realize(DeviceState *dev, Error **errp)
 static void vtd_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    X86IOMMUClass *x86_class = X86_IOMMU_CLASS(klass);
 
     dc->reset = vtd_reset;
-    dc->realize = vtd_realize;
     dc->vmsd = &vtd_vmstate;
     dc->props = vtd_properties;
     dc->hotpluggable = false;
+    x86_class->realize = vtd_realize;
 }
 
 static const TypeInfo vtd_info = {
     .name          = TYPE_INTEL_IOMMU_DEVICE,
-    .parent        = TYPE_SYS_BUS_DEVICE,
+    .parent        = TYPE_X86_IOMMU_DEVICE,
     .instance_size = sizeof(IntelIOMMUState),
     .class_init    = vtd_class_init,
 };

hw/i386/x86-iommu.c

@@ -0,0 +1,53 @@
+/*
+ * QEMU emulation of common X86 IOMMU
+ *
+ * Copyright (C) 2016 Peter Xu, Red Hat <peterx@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/sysbus.h"
+#include "hw/boards.h"
+#include "hw/i386/x86-iommu.h"
+
+static void x86_iommu_realize(DeviceState *dev, Error **errp)
+{
+    X86IOMMUClass *x86_class = X86_IOMMU_GET_CLASS(dev);
+    if (x86_class->realize) {
+        x86_class->realize(dev, errp);
+    }
+}
+
+static void x86_iommu_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    dc->realize = x86_iommu_realize;
+}
+
+static const TypeInfo x86_iommu_info = {
+    .name          = TYPE_X86_IOMMU_DEVICE,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(X86IOMMUState),
+    .class_init    = x86_iommu_class_init,
+    .class_size    = sizeof(X86IOMMUClass),
+    .abstract      = true,
+};
+
+static void x86_iommu_register_types(void)
+{
+    type_register_static(&x86_iommu_info);
+}
+
+type_init(x86_iommu_register_types)

include/hw/i386/intel_iommu.h

@@ -23,6 +23,7 @@
 #define INTEL_IOMMU_H
 #include "hw/qdev.h"
 #include "sysemu/dma.h"
+#include "hw/i386/x86-iommu.h"
 
 #define TYPE_INTEL_IOMMU_DEVICE "intel-iommu"
 #define INTEL_IOMMU_DEVICE(obj) \
@@ -90,7 +91,7 @@ struct VTDIOTLBEntry {
 
 /* The iommu (DMAR) device state struct */
 struct IntelIOMMUState {
-    SysBusDevice busdev;
+    X86IOMMUState x86_iommu;
     MemoryRegion csrmem;
     uint8_t csr[DMAR_REG_SIZE];     /* register values */
     uint8_t wmask[DMAR_REG_SIZE];   /* R/W bytes */

include/hw/i386/x86-iommu.h

@@ -0,0 +1,46 @@
+/*
+ * Common IOMMU interface for X86 platform
+ *
+ * Copyright (C) 2016 Peter Xu, Red Hat <peterx@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef IOMMU_COMMON_H
+#define IOMMU_COMMON_H
+
+#include "hw/sysbus.h"
+
+#define  TYPE_X86_IOMMU_DEVICE  ("x86-iommu")
+#define  X86_IOMMU_DEVICE(obj) \
+    OBJECT_CHECK(X86IOMMUState, (obj), TYPE_X86_IOMMU_DEVICE)
+#define  X86_IOMMU_CLASS(klass) \
+    OBJECT_CLASS_CHECK(X86IOMMUClass, (klass), TYPE_X86_IOMMU_DEVICE)
+#define  X86_IOMMU_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(X86IOMMUClass, obj, TYPE_X86_IOMMU_DEVICE)
+
+typedef struct X86IOMMUState X86IOMMUState;
+typedef struct X86IOMMUClass X86IOMMUClass;
+
+struct X86IOMMUClass {
+    SysBusDeviceClass parent;
+    /* Intel/AMD specific realize() hook */
+    DeviceRealize realize;
+};
+
+struct X86IOMMUState {
+    SysBusDevice busdev;
+};
+
+#endif