diff --git a/hw/ide/macio.c b/hw/ide/macio.c
index db5db39..428fbfc 100644
--- a/hw/ide/macio.c
+++ b/hw/ide/macio.c
@@ -255,131 +255,89 @@ static void pmac_ide_flush(DBDMA_io *io)
 }
 
 /* PowerMac IDE memory IO */
-static void pmac_ide_writeb (void *opaque,
-                             hwaddr addr, uint32_t val)
+static uint64_t pmac_ide_read(void *opaque, hwaddr addr, unsigned size)
 {
     MACIOIDEState *d = opaque;
+    uint64_t retval;
+    addr = (addr & 0xfff) >> 4;
 
-    addr = (addr & 0xFFF) >> 4;
     switch (addr) {
-    case 1 ... 7:
-        ide_ioport_write(&d->bus, addr, val);
-        break;
-    case 8:
-    case 22:
-        ide_cmd_write(&d->bus, 0, val);
-        break;
-    default:
+    case 0x0:
+        if (size == 2) {
+            retval = ide_data_readw(&d->bus, 0);
+        } else if (size == 4) {
+            retval = ide_data_readl(&d->bus, 0);
+        } else {
+            retval = 0xffffffff;
+        }
         break;
-    }
-}
-
-static uint32_t pmac_ide_readb (void *opaque,hwaddr addr)
-{
-    uint8_t retval;
-    MACIOIDEState *d = opaque;
-
-    addr = (addr & 0xFFF) >> 4;
-    switch (addr) {
-    case 1 ... 7:
+    case 0x1 ... 0x7:
         retval = ide_ioport_read(&d->bus, addr);
         break;
-    case 8:
-    case 22:
+    case 0x8:
+    case 0x16:
         retval = ide_status_read(&d->bus, 0);
         break;
+    case 0x20:
+        retval = d->timing_reg;
+        break;
+    case 0x30:
+        /* This is an interrupt state register that only exists
+         * in the KeyLargo and later variants. Bit 0x8000_0000
+         * latches the DMA interrupt and has to be written to
+         * clear. Bit 0x4000_0000 is an image of the disk
+         * interrupt. MacOS X relies on this and will hang if
+         * we don't provide at least the disk interrupt
+         */
+        retval = d->irq_reg;
+        break;
     default:
-        retval = 0xFF;
+        retval = 0xffffffff;
         break;
     }
-    return retval;
-}
-
-static void pmac_ide_writew (void *opaque,
-                             hwaddr addr, uint32_t val)
-{
-    MACIOIDEState *d = opaque;
-
-    addr = (addr & 0xFFF) >> 4;
-    val = bswap16(val);
-    if (addr == 0) {
-        ide_data_writew(&d->bus, 0, val);
-    }
-}
 
-static uint32_t pmac_ide_readw (void *opaque,hwaddr addr)
-{
-    uint16_t retval;
-    MACIOIDEState *d = opaque;
-
-    addr = (addr & 0xFFF) >> 4;
-    if (addr == 0) {
-        retval = ide_data_readw(&d->bus, 0);
-    } else {
-        retval = 0xFFFF;
-    }
-    retval = bswap16(retval);
     return retval;
 }
 
-static void pmac_ide_writel (void *opaque,
-                             hwaddr addr, uint32_t val)
+
+static void pmac_ide_write(void *opaque, hwaddr addr, uint64_t val,
+                           unsigned size)
 {
     MACIOIDEState *d = opaque;
+    addr = (addr & 0xfff) >> 4;
 
-    addr = (addr & 0xFFF) >> 4;
-    val = bswap32(val);
-    if (addr == 0) {
-        ide_data_writel(&d->bus, 0, val);
-    } else if (addr == 0x20) {
+    switch (addr) {
+    case 0x0:
+        if (size == 2) {
+            ide_data_writew(&d->bus, 0, val);
+        } else if (size == 4) {
+            ide_data_writel(&d->bus, 0, val);
+        }
+        break;
+    case 0x1 ... 0x7:
+        ide_ioport_write(&d->bus, addr, val);
+        break;
+    case 0x8:
+    case 0x16:
+        ide_cmd_write(&d->bus, 0, val);
+        break;
+    case 0x20:
         d->timing_reg = val;
-    } else if (addr == 0x30) {
+        break;
+    case 0x30:
         if (val & 0x80000000u) {
             d->irq_reg &= 0x7fffffff;
         }
+        break;
     }
 }
 
-static uint32_t pmac_ide_readl (void *opaque,hwaddr addr)
-{
-    uint32_t retval;
-    MACIOIDEState *d = opaque;
-
-    addr = (addr & 0xFFF) >> 4;
-    if (addr == 0) {
-        retval = ide_data_readl(&d->bus, 0);
-    } else if (addr == 0x20) {
-        retval = d->timing_reg;
-    } else if (addr == 0x30) {
-        /* This is an interrupt state register that only exists
-         * in the KeyLargo and later variants. Bit 0x8000_0000
-         * latches the DMA interrupt and has to be written to
-         * clear. Bit 0x4000_0000 is an image of the disk
-         * interrupt. MacOS X relies on this and will hang if
-         * we don't provide at least the disk interrupt
-         */
-        retval = d->irq_reg;
-    } else {
-        retval = 0xFFFFFFFF;
-    }
-    retval = bswap32(retval);
-    return retval;
-}
-
 static const MemoryRegionOps pmac_ide_ops = {
-    .old_mmio = {
-        .write = {
-            pmac_ide_writeb,
-            pmac_ide_writew,
-            pmac_ide_writel,
-        },
-        .read = {
-            pmac_ide_readb,
-            pmac_ide_readw,
-            pmac_ide_readl,
-        },
-    },
-    .endianness = DEVICE_NATIVE_ENDIAN,
+    .read = pmac_ide_read,
+    .write = pmac_ide_write,
+    .valid.min_access_size = 1,
+    .valid.max_access_size = 4,
+    .endianness = DEVICE_LITTLE_ENDIAN,
 };
 
 static const VMStateDescription vmstate_pmac = {
