hw/m68k: add Nubus support

This patch adds basic support for the NuBus bus. This is used by 680x0
Macintosh.

Co-developed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Thomas Huth <huth@tuxfamily.org>
Message-Id: <20191026164546.30020-8-laurent@vivier.eu>

1 files changed, 215 insertions, 0 deletions

diff --git a/hw/nubus/nubus-device.c b/hw/nubus/nubus-device.c
new file mode 100644
index 0000000000..01ccad9e8e
--- /dev/null
+++ b/hw/nubus/nubus-device.c
@@ -0,0 +1,215 @@
+/*
+ * QEMU Macintosh Nubus
+ *
+ * Copyright (c) 2013-2018 Laurent Vivier <laurent@vivier.eu>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "hw/nubus/nubus.h"
+#include "qapi/error.h"
+
+
+/* The Format Block Structure */
+
+#define FBLOCK_DIRECTORY_OFFSET 0
+#define FBLOCK_LENGTH           4
+#define FBLOCK_CRC              8
+#define FBLOCK_REVISION_LEVEL   12
+#define FBLOCK_FORMAT           13
+#define FBLOCK_TEST_PATTERN     14
+#define FBLOCK_RESERVED         18
+#define FBLOCK_BYTE_LANES       19
+
+#define FBLOCK_SIZE             20
+#define FBLOCK_PATTERN_VAL      0x5a932bc7
+
+static uint64_t nubus_fblock_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    NubusDevice *dev = opaque;
+    uint64_t val;
+
+#define BYTE(v, b) (((v) >> (24 - 8 * (b))) & 0xff)
+    switch (addr) {
+    case FBLOCK_BYTE_LANES:
+        val = dev->byte_lanes;
+        val |= (val ^ 0xf) << 4;
+        break;
+    case FBLOCK_RESERVED:
+        val = 0x00;
+        break;
+    case FBLOCK_TEST_PATTERN...FBLOCK_TEST_PATTERN + 3:
+        val = BYTE(FBLOCK_PATTERN_VAL, addr - FBLOCK_TEST_PATTERN);
+        break;
+    case FBLOCK_FORMAT:
+        val = dev->rom_format;
+        break;
+    case FBLOCK_REVISION_LEVEL:
+        val = dev->rom_rev;
+        break;
+    case FBLOCK_CRC...FBLOCK_CRC + 3:
+        val = BYTE(dev->rom_crc, addr - FBLOCK_CRC);
+        break;
+    case FBLOCK_LENGTH...FBLOCK_LENGTH + 3:
+        val = BYTE(dev->rom_length, addr - FBLOCK_LENGTH);
+        break;
+    case FBLOCK_DIRECTORY_OFFSET...FBLOCK_DIRECTORY_OFFSET + 3:
+        val = BYTE(dev->directory_offset, addr - FBLOCK_DIRECTORY_OFFSET);
+        break;
+    default:
+        val = 0;
+        break;
+    }
+    return val;
+}
+
+static void nubus_fblock_write(void *opaque, hwaddr addr, uint64_t val,
+                               unsigned int size)
+{
+    /* read only */
+}
+
+static const MemoryRegionOps nubus_format_block_ops = {
+    .read = nubus_fblock_read,
+    .write = nubus_fblock_write,
+    .endianness = DEVICE_BIG_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 1,
+    }
+};
+
+static void nubus_register_format_block(NubusDevice *dev)
+{
+    char *fblock_name;
+
+    fblock_name = g_strdup_printf("nubus-slot-%d-format-block",
+                                  dev->slot_nb);
+
+    hwaddr fblock_offset = memory_region_size(&dev->slot_mem) - FBLOCK_SIZE;
+    memory_region_init_io(&dev->fblock_io, NULL, &nubus_format_block_ops,
+                          dev, fblock_name, FBLOCK_SIZE);
+    memory_region_add_subregion(&dev->slot_mem, fblock_offset,
+                                &dev->fblock_io);
+
+    g_free(fblock_name);
+}
+
+static void mac_nubus_rom_write(void *opaque, hwaddr addr, uint64_t val,
+                                       unsigned int size)
+{
+    /* read only */
+}
+
+static uint64_t mac_nubus_rom_read(void *opaque, hwaddr addr,
+                                    unsigned int size)
+{
+    NubusDevice *dev = opaque;
+
+    return dev->rom[addr];
+}
+
+static const MemoryRegionOps mac_nubus_rom_ops = {
+    .read  = mac_nubus_rom_read,
+    .write = mac_nubus_rom_write,
+    .endianness = DEVICE_BIG_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 1,
+    },
+};
+
+
+void nubus_register_rom(NubusDevice *dev, const uint8_t *rom, uint32_t size,
+                        int revision, int format, uint8_t byte_lanes)
+{
+    hwaddr rom_offset;
+    char *rom_name;
+
+    /* FIXME : really compute CRC */
+    dev->rom_length = 0;
+    dev->rom_crc = 0;
+
+    dev->rom_rev = revision;
+    dev->rom_format = format;
+
+    dev->byte_lanes = byte_lanes;
+    dev->directory_offset = -size;
+
+    /* ROM */
+
+    dev->rom = rom;
+    rom_name = g_strdup_printf("nubus-slot-%d-rom", dev->slot_nb);
+    memory_region_init_io(&dev->rom_io, NULL, &mac_nubus_rom_ops,
+                          dev, rom_name, size);
+    memory_region_set_readonly(&dev->rom_io, true);
+
+    rom_offset = memory_region_size(&dev->slot_mem) - FBLOCK_SIZE +
+                 dev->directory_offset;
+    memory_region_add_subregion(&dev->slot_mem, rom_offset, &dev->rom_io);
+
+    g_free(rom_name);
+}
+
+static void nubus_device_realize(DeviceState *dev, Error **errp)
+{
+    NubusBus *nubus = NUBUS_BUS(qdev_get_parent_bus(DEVICE(dev)));
+    NubusDevice *nd = NUBUS_DEVICE(dev);
+    char *name;
+    hwaddr slot_offset;
+
+    if (nubus->current_slot < NUBUS_FIRST_SLOT ||
+            nubus->current_slot > NUBUS_LAST_SLOT) {
+        error_setg(errp, "Cannot register nubus card, not enough slots");
+        return;
+    }
+
+    nd->slot_nb = nubus->current_slot++;
+    name = g_strdup_printf("nubus-slot-%d", nd->slot_nb);
+
+    if (nd->slot_nb < NUBUS_FIRST_SLOT) {
+        /* Super */
+        slot_offset = (nd->slot_nb - 6) * NUBUS_SUPER_SLOT_SIZE;
+
+        memory_region_init(&nd->slot_mem, OBJECT(dev), name,
+                           NUBUS_SUPER_SLOT_SIZE);
+        memory_region_add_subregion(&nubus->super_slot_io, slot_offset,
+                                    &nd->slot_mem);
+    } else {
+        /* Normal */
+        slot_offset = nd->slot_nb * NUBUS_SLOT_SIZE;
+
+        memory_region_init(&nd->slot_mem, OBJECT(dev), name, NUBUS_SLOT_SIZE);
+        memory_region_add_subregion(&nubus->slot_io, slot_offset,
+                                    &nd->slot_mem);
+    }
+
+    g_free(name);
+    nubus_register_format_block(nd);
+}
+
+static void nubus_device_class_init(ObjectClass *oc, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(oc);
+
+    dc->realize = nubus_device_realize;
+    dc->bus_type = TYPE_NUBUS_BUS;
+}
+
+static const TypeInfo nubus_device_type_info = {
+    .name = TYPE_NUBUS_DEVICE,
+    .parent = TYPE_DEVICE,
+    .abstract = true,
+    .instance_size = sizeof(NubusDevice),
+    .class_init = nubus_device_class_init,
+};
+
+static void nubus_register_types(void)
+{
+    type_register_static(&nubus_device_type_info);
+}
+
+type_init(nubus_register_types)