q800: add Apple Sound Chip (ASC) audio to machine

The Quadra 800 has the enhanced ASC (EASC) audio chip which supports both the
legacy IRQ routing through VIA2 and also "A/UX" mode routing direct to the
CPU.

Co-developed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-ID: <20231004083806.757242-10-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

hw/m68k/q800-glue.c

@@ -97,6 +97,11 @@ static void GLUE_set_irq(void *opaque, int irq, int level)
             irq = 6;
             break;
 
+        case GLUE_IRQ_IN_ASC:
+            /* Route to VIA2 instead, negative edge-triggered */
+            qemu_set_irq(s->irqs[GLUE_IRQ_ASC], !level);
+            return;
+
         default:
             g_assert_not_reached();
         }
@@ -123,6 +128,10 @@ static void GLUE_set_irq(void *opaque, int irq, int level)
             irq = 6;
             break;
 
+        case GLUE_IRQ_IN_ASC:
+            irq = 4;
+            break;
+
         default:
             g_assert_not_reached();
         }
@@ -214,7 +223,7 @@ static void glue_init(Object *obj)
     qdev_init_gpio_in(dev, GLUE_set_irq, 8);
     qdev_init_gpio_in_named(dev, glue_auxmode_set_irq, "auxmode", 1);
 
-    qdev_init_gpio_out(dev, s->irqs, 1);
+    qdev_init_gpio_out(dev, s->irqs, 2);
 
     /* NMI release timer */
     s->nmi_release = timer_new_ms(QEMU_CLOCK_VIRTUAL, glue_nmi_release, s);

hw/m68k/q800.c

@@ -43,6 +43,7 @@
 #include "hw/misc/djmemc.h"
 #include "hw/misc/iosb.h"
 #include "hw/input/adb.h"
+#include "hw/audio/asc.h"
 #include "hw/nubus/mac-nubus-bridge.h"
 #include "hw/display/macfb.h"
 #include "hw/block/swim.h"
@@ -480,6 +481,25 @@ static void q800_machine_init(MachineState *machine)
 
     scsi_bus_legacy_handle_cmdline(&esp->bus);
 
+    /* Apple Sound Chip */
+
+    object_initialize_child(OBJECT(machine), "asc", &m->asc, TYPE_ASC);
+    qdev_prop_set_uint8(DEVICE(&m->asc), "asctype", ASC_TYPE_EASC);
+    if (machine->audiodev) {
+        qdev_prop_set_string(DEVICE(&m->asc), "audiodev", machine->audiodev);
+    }
+    sysbus = SYS_BUS_DEVICE(&m->asc);
+    sysbus_realize_and_unref(sysbus, &error_fatal);
+    memory_region_add_subregion(&m->macio, ASC_BASE - IO_BASE,
+                                sysbus_mmio_get_region(sysbus, 0));
+    sysbus_connect_irq(sysbus, 0, qdev_get_gpio_in(DEVICE(&m->glue),
+                                                   GLUE_IRQ_IN_ASC));
+
+    /* Wire ASC IRQ via GLUE for use in classic mode */
+    qdev_connect_gpio_out(DEVICE(&m->glue), GLUE_IRQ_ASC,
+                          qdev_get_gpio_in(DEVICE(&m->via2),
+                                           VIA2_IRQ_ASC_BIT));
+
     /* SWIM floppy controller */
 
     object_initialize_child(OBJECT(machine), "swim", &m->swim,
@@ -688,6 +708,7 @@ static void q800_machine_class_init(ObjectClass *oc, void *data)
     mc->max_cpus = 1;
     mc->block_default_type = IF_SCSI;
     mc->default_ram_id = "m68k_mac.ram";
+    machine_add_audiodev_property(mc);
     compat_props_add(mc->compat_props, hw_compat_q800, hw_compat_q800_len);
 }
 

include/hw/m68k/q800-glue.h

@@ -35,7 +35,7 @@ struct GLUEState {
     M68kCPU *cpu;
     uint8_t ipr;
     uint8_t auxmode;
-    qemu_irq irqs[1];
+    qemu_irq irqs[2];
     QEMUTimer *nmi_release;
 };
 
@@ -44,7 +44,9 @@ struct GLUEState {
 #define GLUE_IRQ_IN_SONIC      2
 #define GLUE_IRQ_IN_ESCC       3
 #define GLUE_IRQ_IN_NMI        4
+#define GLUE_IRQ_IN_ASC        5
 
 #define GLUE_IRQ_NUBUS_9       0
+#define GLUE_IRQ_ASC           1
 
 #endif

include/hw/m68k/q800.h

@@ -38,6 +38,7 @@
 #include "hw/display/macfb.h"
 #include "hw/misc/djmemc.h"
 #include "hw/misc/iosb.h"
+#include "hw/audio/asc.h"
 
 /*
  * The main Q800 machine
@@ -60,6 +61,7 @@ struct Q800MachineState {
     MacfbNubusState macfb;
     DJMEMCState djmemc;
     IOSBState iosb;
+    ASCState asc;
     MemoryRegion ramio;
     MemoryRegion macio;
     MemoryRegion macio_alias;