next-cube: move floppy disk MMIO to separate memory region in next-pc

The dummy floppy disk device is part of the next-pc device, and not related to
the NeXTCube SCRs.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Thomas Huth <huth@tuxfamily.org>
Message-ID: <20241222130012.1013374-10-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Thomas Huth <huth@tuxfamily.org>

hw/m68k/next-cube.c

@@ -108,6 +108,7 @@ struct NeXTPC {
 
     M68kCPU *cpu;
 
+    MemoryRegion floppy_mem;
     MemoryRegion mmiomem;
     MemoryRegion scrmem;
 
@@ -368,11 +369,6 @@ static uint64_t next_scr_readfn(void *opaque, hwaddr addr, unsigned size)
     uint64_t val;
 
     switch (addr) {
-    case 0x14108:
-        DPRINTF("FD read @ %x\n", (unsigned int)addr);
-        val = 0x40 | 0x04 | 0x2 | 0x1;
-        break;
-
     /*
      * These 4 registers are the hardware timer, not sure which register
      * is the latch instead of data, but no problems so far.
@@ -402,13 +398,6 @@ static void next_scr_writefn(void *opaque, hwaddr addr, uint64_t val,
                              unsigned size)
 {
     switch (addr) {
-    case 0x14108:
-        DPRINTF("FDCSR Write: %"PRIx64 "\n", val);
-        if (val == 0x0) {
-            /* qemu_irq_raise(s->fd_irq[0]); */
-        }
-        break;
-
     /* Hardware timer latch - not implemented yet */
     case 0x1a000:
     default:
@@ -948,6 +937,47 @@ static const TypeInfo next_scsi_info = {
     .class_init = next_scsi_class_init,
 };
 
+static void next_floppy_write(void *opaque, hwaddr addr, uint64_t val,
+                              unsigned size)
+{
+    switch (addr) {
+    case 0:
+        DPRINTF("FDCSR Write: %"PRIx64 "\n", val);
+        if (val == 0x0) {
+            /* qemu_irq_raise(s->fd_irq[0]); */
+        }
+        break;
+
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static uint64_t next_floppy_read(void *opaque, hwaddr addr, unsigned size)
+{
+    uint64_t val;
+
+    switch (addr) {
+    case 0:
+        DPRINTF("FD read @ %x\n", (unsigned int)addr);
+        val = 0x40 | 0x04 | 0x2 | 0x1;
+        break;
+
+    default:
+        g_assert_not_reached();
+    }
+
+    return val;
+}
+
+static const MemoryRegionOps next_floppy_ops = {
+    .read = next_floppy_read,
+    .write = next_floppy_write,
+    .valid.min_access_size = 1,
+    .valid.max_access_size = 4,
+    .endianness = DEVICE_BIG_ENDIAN,
+};
+
 static void next_escc_init(DeviceState *pcdev)
 {
     DeviceState *dev;
@@ -1006,6 +1036,10 @@ static void next_pc_realize(DeviceState *dev, Error **errp)
 
     s->scsi_reset = qdev_get_gpio_in(d, 0);
     s->scsi_dma = qdev_get_gpio_in(d, 1);
+
+    /* Floppy */
+    memory_region_add_subregion(&s->scrmem, 0x14108,
+                                &s->floppy_mem);
 }
 
 static void next_pc_init(Object *obj)
@@ -1024,6 +1058,9 @@ static void next_pc_init(Object *obj)
     sysbus_init_mmio(sbd, &s->scrmem);
 
     object_initialize_child(obj, "next-scsi", &s->next_scsi, TYPE_NEXT_SCSI);
+
+    memory_region_init_io(&s->floppy_mem, OBJECT(s), &next_floppy_ops, s,
+                          "next.floppy", 4);
 }
 
 /*