[v3,10/20] q800: add easc bool machine class property to switch between ASC and EASC

Commit Message

Mark Cave-Ayland Sept. 29, 2023, 5:59 p.m. UTC

This determines whether the Apple Sound Chip (ASC) is set to enhanced mode
(default) or to original mode. The real Q800 hardware used an EASC chip however
a lot of older software only works with the older ASC chip.

Adding this as a machine parameter allows QEMU to be used as an developer aid
for testing and migrating code from ASC to EASC.

Signed-off-by: Mark Cave-Ayland <[e-mail]>
Reviewed-by: Philippe Mathieu-Daudé <[e-mail]>
Reviewed-by: Laurent Vivier <[e-mail]>
---
 hw/m68k/q800.c         | 30 +++++++++++++++++++++++++++++-
 include/hw/m68k/q800.h |  1 +
 2 files changed, 30 insertions(+), 1 deletion(-)

Patch

diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
index ae07aa20ff..5ae7c37760 100644
--- a/hw/m68k/q800.c
+++ b/hw/m68k/q800.c
@@ -484,7 +484,8 @@  static void q800_machine_init(MachineState *machine)
     /* Apple Sound Chip */
 
     object_initialize_child(OBJECT(machine), "asc", &m->asc, TYPE_ASC);
-    qdev_prop_set_uint8(DEVICE(&m->asc), "asctype", ASC_TYPE_EASC);
+    qdev_prop_set_uint8(DEVICE(&m->asc), "asctype", m->easc ? ASC_TYPE_EASC
+                                                            : ASC_TYPE_ASC);
     sysbus = SYS_BUS_DEVICE(&m->asc);
     sysbus_realize_and_unref(sysbus, &error_fatal);
     memory_region_add_subregion(&m->macio, ASC_BASE - IO_BASE,
@@ -674,6 +675,28 @@  static void q800_machine_init(MachineState *machine)
     }
 }
 
+static bool q800_get_easc(Object *obj, Error **errp)
+{
+    Q800MachineState *ms = Q800_MACHINE(obj);
+
+    return ms->easc;
+}
+
+static void q800_set_easc(Object *obj, bool value, Error **errp)
+{
+    Q800MachineState *ms = Q800_MACHINE(obj);
+
+    ms->easc = value;
+}
+
+static void q800_init(Object *obj)
+{
+    Q800MachineState *ms = Q800_MACHINE(obj);
+
+    /* Default to EASC */
+    ms->easc = true;
+}
+
 static GlobalProperty hw_compat_q800[] = {
     { "scsi-hd", "quirk_mode_page_vendor_specific_apple", "on" },
     { "scsi-hd", "vendor", " SEAGATE" },
@@ -706,11 +729,16 @@  static void q800_machine_class_init(ObjectClass *oc, void *data)
     mc->block_default_type = IF_SCSI;
     mc->default_ram_id = "m68k_mac.ram";
     compat_props_add(mc->compat_props, hw_compat_q800, hw_compat_q800_len);
+
+    object_class_property_add_bool(oc, "easc", q800_get_easc, q800_set_easc);
+    object_class_property_set_description(oc, "easc",
+        "Set to off to use ASC rather than EASC");
 }
 
 static const TypeInfo q800_machine_typeinfo = {
     .name       = MACHINE_TYPE_NAME("q800"),
     .parent     = TYPE_MACHINE,
+    .instance_init = q800_init,
     .instance_size = sizeof(Q800MachineState),
     .class_init = q800_machine_class_init,
 };
diff --git a/include/hw/m68k/q800.h b/include/hw/m68k/q800.h
index 790cf433f3..fbaacd88bd 100644
--- a/include/hw/m68k/q800.h
+++ b/include/hw/m68k/q800.h
@@ -47,6 +47,7 @@ 
 struct Q800MachineState {
     MachineState parent_obj;
 
+    bool easc;
     M68kCPU cpu;
     MemoryRegion rom;
     GLUEState glue;