nubus-bridge: introduce separate NubusBridge structure

This is to allow the Nubus bridge to store its own additional state. Also update
the comment in the file header to reflect that nubus-bridge is not specific to
the Macintosh.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210924073808.1041-14-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

hw/nubus/nubus-bridge.c

 /*
- * QEMU Macintosh Nubus
+ * QEMU Nubus
  *
  * Copyright (c) 2013-2018 Laurent Vivier <laurent@vivier.eu>
  *
@@ -22,7 +22,7 @@ static void nubus_bridge_class_init(ObjectClass *klass, void *data)
 static const TypeInfo nubus_bridge_info = {
     .name          = TYPE_NUBUS_BRIDGE,
     .parent        = TYPE_SYS_BUS_DEVICE,
-    .instance_size = sizeof(SysBusDevice),
+    .instance_size = sizeof(NubusBridge),
     .class_init    = nubus_bridge_class_init,
 };
 

include/hw/nubus/mac-nubus-bridge.h

@@ -20,7 +20,7 @@
 OBJECT_DECLARE_SIMPLE_TYPE(MacNubusState, MAC_NUBUS_BRIDGE)
 
 struct MacNubusState {
-    SysBusDevice sysbus_dev;
+    NubusBridge parent_obj;
 
     NubusBus *bus;
     MemoryRegion super_slot_alias;

include/hw/nubus/nubus.h

@@ -10,6 +10,7 @@
 #define HW_NUBUS_NUBUS_H
 
 #include "hw/qdev-properties.h"
+#include "hw/sysbus.h"
 #include "exec/address-spaces.h"
 #include "qom/object.h"
 #include "qemu/units.h"
@@ -32,6 +33,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(NubusDevice, NUBUS_DEVICE)
 OBJECT_DECLARE_SIMPLE_TYPE(NubusBus, NUBUS_BUS)
 
 #define TYPE_NUBUS_BRIDGE "nubus-bridge"
+OBJECT_DECLARE_SIMPLE_TYPE(NubusBridge, NUBUS_BRIDGE);
 
 struct NubusBus {
     BusState qbus;
@@ -58,4 +60,8 @@ struct NubusDevice {
     MemoryRegion decl_rom;
 };
 
+struct NubusBridge {
+    SysBusDevice parent_obj;
+};
+
 #endif