[PATCH v2] mos6522: remove anh register

[Laurent Vivier <laurent@vivier.eu>]

Register addr 1 is defined as buffer A with handshake (vBufAH),
register addr 15 is also defined as buffer A without handshake (vBufA).

As both addresses access the same register, remove the definition of
'anh' and use only 'a' (with VIA_REG_ANH and VIA_REG_A).

Fixes: 51f233ec92cd ("misc: introduce new mos6522 VIA device and enable it for ppc builds")
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
---

Notes:
    v2: update commit message (remove reference to linux)
        add LOG_UNIMP for VIA_REG_A access

 hw/misc/mos6522.c         | 16 ++++++++--------
 include/hw/misc/mos6522.h |  1 -
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/hw/misc/mos6522.c b/hw/misc/mos6522.c
index cecf0be59e..10b85bf751 100644
--- a/hw/misc/mos6522.c
+++ b/hw/misc/mos6522.c
@@ -244,6 +244,9 @@ uint64_t mos6522_read(void *opaque, hwaddr addr, unsigned size)
         val = s->b;
         break;
     case VIA_REG_A:
+       qemu_log_mask(LOG_UNIMP, "Read access to register A with handshake");
+       /* fall through */
+    case VIA_REG_ANH:
         val = s->a;
         break;
     case VIA_REG_DIRB:
@@ -297,9 +300,7 @@ uint64_t mos6522_read(void *opaque, hwaddr addr, unsigned size)
         val = s->ier | 0x80;
         break;
     default:
-    case VIA_REG_ANH:
-        val = s->anh;
-        break;
+        g_assert_not_reached();
     }
 
     if (addr != VIA_REG_IFR || val != 0) {
@@ -322,6 +323,9 @@ void mos6522_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
         mdc->portB_write(s);
         break;
     case VIA_REG_A:
+       qemu_log_mask(LOG_UNIMP, "Write access to register A with handshake");
+       /* fall through */
+    case VIA_REG_ANH:
         s->a = (s->a & ~s->dira) | (val & s->dira);
         mdc->portA_write(s);
         break;
@@ -395,9 +399,7 @@ void mos6522_write(void *opaque, hwaddr addr, uint64_t val, unsigned size)
                               qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
         break;
     default:
-    case VIA_REG_ANH:
-        s->anh = val;
-        break;
+        g_assert_not_reached();
     }
 }
 
@@ -439,7 +441,6 @@ const VMStateDescription vmstate_mos6522 = {
         VMSTATE_UINT8(pcr, MOS6522State),
         VMSTATE_UINT8(ifr, MOS6522State),
         VMSTATE_UINT8(ier, MOS6522State),
-        VMSTATE_UINT8(anh, MOS6522State),
         VMSTATE_STRUCT_ARRAY(timers, MOS6522State, 2, 0,
                              vmstate_mos6522_timer, MOS6522Timer),
         VMSTATE_END_OF_LIST()
@@ -460,7 +461,6 @@ static void mos6522_reset(DeviceState *dev)
     s->ifr = 0;
     s->ier = 0;
     /* s->ier = T1_INT | SR_INT; */
-    s->anh = 0;
 
     s->timers[0].frequency = s->frequency;
     s->timers[0].latch = 0xffff;
diff --git a/include/hw/misc/mos6522.h b/include/hw/misc/mos6522.h
index 493c907537..97384c6e02 100644
--- a/include/hw/misc/mos6522.h
+++ b/include/hw/misc/mos6522.h
@@ -115,7 +115,6 @@ typedef struct MOS6522State {
     uint8_t pcr;
     uint8_t ifr;
     uint8_t ier;
-    uint8_t anh;
 
     MOS6522Timer timers[2];
     uint64_t frequency;
-- 
2.24.1