mac_via: add GPIO for A/UX mode

Add a new auxmode GPIO that is updated when port B bit 6 is changed indicating
whether the hardware is configured for A/UX mode.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20211020134131.4392-5-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

hw/misc/mac_via.c

@@ -880,6 +880,21 @@ static void via1_adb_update(MOS6522Q800VIA1State *v1s)
     }
 }
 
+static void via1_auxmode_update(MOS6522Q800VIA1State *v1s)
+{
+    MOS6522State *s = MOS6522(v1s);
+    int oldirq, irq;
+
+    oldirq = (v1s->last_b & VIA1B_vMystery) ? 1 : 0;
+    irq = (s->b & VIA1B_vMystery) ? 1 : 0;
+
+    /* Check to see if the A/UX mode bit has changed */
+    if (irq != oldirq) {
+        trace_via1_auxmode(irq);
+        qemu_set_irq(v1s->auxmode_irq, irq);
+    }
+}
+
 static uint64_t mos6522_q800_via1_read(void *opaque, hwaddr addr, unsigned size)
 {
     MOS6522Q800VIA1State *s = MOS6522_Q800_VIA1(opaque);
@@ -902,6 +917,7 @@ static void mos6522_q800_via1_write(void *opaque, hwaddr addr, uint64_t val,
     case VIA_REG_B:
         via1_rtc_update(v1s);
         via1_adb_update(v1s);
+        via1_auxmode_update(v1s);
 
         v1s->last_b = ms->b;
         break;
@@ -1046,6 +1062,9 @@ static void mos6522_q800_via1_init(Object *obj)
               TYPE_ADB_BUS, DEVICE(v1s), "adb.0");
 
     qdev_init_gpio_in(DEVICE(obj), via1_irq_request, VIA1_IRQ_NB);
+
+    /* A/UX mode */
+    qdev_init_gpio_out(DEVICE(obj), &v1s->auxmode_irq, 1);
 }
 
 static const VMStateDescription vmstate_q800_via1 = {

hw/misc/trace-events

@@ -228,6 +228,7 @@ via1_rtc_cmd_pram_sect_write(int sector, int offset, int addr, int value) "secto
 via1_adb_send(const char *state, uint8_t data, const char *vadbint) "state %s data=0x%02x vADBInt=%s"
 via1_adb_receive(const char *state, uint8_t data, const char *vadbint, int status, int index, int size) "state %s data=0x%02x vADBInt=%s status=0x%x index=%d size=%d"
 via1_adb_poll(uint8_t data, const char *vadbint, int status, int index, int size) "data=0x%02x vADBInt=%s status=0x%x index=%d size=%d"
+via1_auxmode(int mode) "setting auxmode to %d"
 
 # grlib_ahb_apb_pnp.c
 grlib_ahb_pnp_read(uint64_t addr, uint32_t value) "AHB PnP read addr:0x%03"PRIx64" data:0x%08x"

include/hw/misc/mac_via.h

@@ -43,6 +43,7 @@ struct MOS6522Q800VIA1State {
     MemoryRegion via_mem;
 
     qemu_irq irqs[VIA1_IRQ_NB];
+    qemu_irq auxmode_irq;
     uint8_t last_b;
 
     /* RTC */