diff mbox series

[v3,3/4] m68k: Add NeXTcube machine

Message ID 20190706154308.7280-4-huth@tuxfamily.org
State New
Headers show
Series None | expand

Commit Message

Thomas Huth July 6, 2019, 3:43 p.m. UTC
It is still quite incomplete (no SCSI, no floppy emulation, no network,
etc.), but the firmware already shows up the debug monitor prompt in the
framebuffer display, so at least the very basics are already working.

This code has been taken from Bryce Lanham's GSoC 2011 NeXT branch at

 https://github.com/blanham/qemu-NeXT/blob/next-cube/hw/next-cube.c

and altered quite a bit to fit the latest interface and coding conventions
of the current QEMU.

Signed-off-by: Thomas Huth <huth@tuxfamily.org>
---
 hw/m68k/Makefile.objs       |   2 +-
 hw/m68k/next-cube.c         | 972 ++++++++++++++++++++++++++++++++++++
 include/hw/m68k/next-cube.h |  38 ++
 3 files changed, 1011 insertions(+), 1 deletion(-)
 create mode 100644 hw/m68k/next-cube.c
diff mbox series

Patch

diff --git a/hw/m68k/Makefile.objs b/hw/m68k/Makefile.objs
index 688002cac1..f25854730d 100644
--- a/hw/m68k/Makefile.objs
+++ b/hw/m68k/Makefile.objs
@@ -1,3 +1,3 @@ 
 obj-$(CONFIG_AN5206) += an5206.o mcf5206.o
 obj-$(CONFIG_MCF5208) += mcf5208.o mcf_intc.o
-obj-$(CONFIG_NEXTCUBE) += next-kbd.o
+obj-$(CONFIG_NEXTCUBE) += next-kbd.o next-cube.o
diff --git a/hw/m68k/next-cube.c b/hw/m68k/next-cube.c
new file mode 100644
index 0000000000..ee96547544
--- /dev/null
+++ b/hw/m68k/next-cube.c
@@ -0,0 +1,972 @@ 
+/*
+ * NeXT Cube System Driver
+ *
+ * Copyright (c) 2011 Bryce Lanham
+ *
+ * This code is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License,
+ * or (at your option) any later version.
+ */
+
+#include "qemu/osdep.h"
+#include "exec/hwaddr.h"
+#include "exec/address-spaces.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/qtest.h"
+#include "hw/hw.h"
+#include "hw/m68k/next-cube.h"
+#include "hw/boards.h"
+#include "hw/loader.h"
+#include "hw/scsi/esp.h"
+#include "hw/sysbus.h"
+#include "hw/char/escc.h" /* ZILOG 8530 Serial Emulation */
+#include "hw/block/fdc.h"
+#include "qapi/error.h"
+#include "ui/console.h"
+#include "target/m68k/cpu.h"
+
+/* #define DEBUG_NEXT */
+#ifdef DEBUG_NEXT
+#define DPRINTF(fmt, ...) \
+    do { printf("NeXT: " fmt , ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) do { } while (0)
+#endif
+
+#define TYPE_NEXT_MACHINE MACHINE_TYPE_NAME("next-cube")
+#define NEXT_MACHINE(obj) OBJECT_CHECK(NeXTState, (obj), TYPE_NEXT_MACHINE)
+
+#define ENTRY       0x0100001e
+#define RAM_SIZE    0x4000000
+#define ROM_FILE    "Rev_2.5_v66.bin"
+
+typedef struct next_dma {
+    uint32_t csr;
+
+    uint32_t saved_next;
+    uint32_t saved_limit;
+    uint32_t saved_start;
+    uint32_t saved_stop;
+
+    uint32_t next;
+    uint32_t limit;
+    uint32_t start;
+    uint32_t stop;
+
+    uint32_t next_initbuf;
+    uint32_t size;
+} next_dma;
+
+typedef struct {
+    MachineState parent;
+
+    uint32_t int_mask;
+    uint32_t int_status;
+
+    uint8_t scsi_csr_1;
+    uint8_t scsi_csr_2;
+    next_dma dma[10];
+    qemu_irq *scsi_irq;
+    qemu_irq scsi_dma;
+    qemu_irq scsi_reset;
+    qemu_irq *fd_irq;
+
+    uint32_t scr1;
+    uint32_t scr2;
+
+    uint8_t rtc_ram[32];
+} NeXTState;
+
+/* Thanks to NeXT forums for this */
+/*
+static const uint8_t rtc_ram3[32] = {
+    0x94, 0x0f, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xfb, 0x6d, 0x00, 0x00, 0x7B, 0x00,
+    0x00, 0x00, 0x65, 0x6e, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x50, 0x13
+};
+*/
+static const uint8_t rtc_ram2[32] = {
+    0x94, 0x0f, 0x40, 0x03, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0xfb, 0x6d, 0x00, 0x00, 0x4b, 0x00,
+    0x41, 0x00, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x84, 0x7e,
+};
+
+#define SCR2_RTCLK 0x2
+#define SCR2_RTDATA 0x4
+#define SCR2_TOBCD(x) (((x / 10) << 4) + (x % 10))
+
+static void nextscr2_write(NeXTState *s, uint32_t val, int size)
+{
+    static int led;
+    static int phase;
+    static uint8_t old_scr2;
+    static uint8_t rtc_command;
+    static uint8_t rtc_value;
+    static uint8_t rtc_status = 0x90;
+    static uint8_t rtc_return;
+    uint8_t scr2_2;
+
+    if (size == 4) {
+        scr2_2 = (val >> 8) & 0xFF;
+    } else {
+        scr2_2 = val & 0xFF;
+    }
+
+    if (val & 0x1) {
+        DPRINTF("fault!\n");
+        led++;
+        if (led == 10) {
+            DPRINTF("LED flashing, possible fault!\n");
+            led = 0;
+        }
+    }
+
+    if (scr2_2 & 0x1) {
+        /* DPRINTF("RTC %x phase %i\n", scr2_2, phase); */
+        if (phase == -1) {
+            phase = 0;
+        }
+        /* If we are in going down clock... do something */
+        if (((old_scr2 & SCR2_RTCLK) != (scr2_2 & SCR2_RTCLK)) &&
+                ((scr2_2 & SCR2_RTCLK) == 0)) {
+            if (phase < 8) {
+                rtc_command = (rtc_command << 1) |
+                              ((scr2_2 & SCR2_RTDATA) ? 1 : 0);
+            }
+            if (phase >= 8 && phase < 16) {
+                rtc_value = (rtc_value << 1) | ((scr2_2 & SCR2_RTDATA) ? 1 : 0);
+
+                /* if we read RAM register, output RT_DATA bit */
+                if (rtc_command <= 0x1F) {
+                    scr2_2 = scr2_2 & (~SCR2_RTDATA);
+                    if (s->rtc_ram[rtc_command] & (0x80 >> (phase - 8))) {
+                        scr2_2 |= SCR2_RTDATA;
+                    }
+
+                    rtc_return = (rtc_return << 1) |
+                                 ((scr2_2 & SCR2_RTDATA) ? 1 : 0);
+                }
+                /* read the status 0x30 */
+                if (rtc_command == 0x30) {
+                    scr2_2 = scr2_2 & (~SCR2_RTDATA);
+                    /* for now status = 0x98 (new rtc + FTU) */
+                    if (rtc_status & (0x80 >> (phase - 8))) {
+                        scr2_2 |= SCR2_RTDATA;
+                    }
+
+                    rtc_return = (rtc_return << 1) |
+                                 ((scr2_2 & SCR2_RTDATA) ? 1 : 0);
+                }
+                /* read the status 0x31 */
+                if (rtc_command == 0x31) {
+                    scr2_2 = scr2_2 & (~SCR2_RTDATA);
+                    /* for now 0x00 */
+                    if (0x00 & (0x80 >> (phase - 8))) {
+                        scr2_2 |= SCR2_RTDATA;
+                    }
+                    rtc_return = (rtc_return << 1) |
+                                 ((scr2_2 & SCR2_RTDATA) ? 1 : 0);
+                }
+
+                if ((rtc_command >= 0x20) && (rtc_command <= 0x2F)) {
+                    scr2_2 = scr2_2 & (~SCR2_RTDATA);
+                    /* for now 0x00 */
+                    time_t time_h = time(NULL);
+                    struct tm *info = localtime(&time_h);
+                    int ret = 0;
+
+                    switch (rtc_command) {
+                    case 0x20:
+                        ret = SCR2_TOBCD(info->tm_sec);
+                        break;
+                    case 0x21:
+                        ret = SCR2_TOBCD(info->tm_min);
+                        break;
+                    case 0x22:
+                        ret = SCR2_TOBCD(info->tm_hour);
+                        break;
+                    case 0x24:
+                        ret = SCR2_TOBCD(info->tm_mday);
+                        break;
+                    case 0x25:
+                        ret = SCR2_TOBCD((info->tm_mon + 1));
+                        break;
+                    case 0x26:
+                        ret = SCR2_TOBCD((info->tm_year - 100));
+                        break;
+
+                    }
+
+                    if (ret & (0x80 >> (phase - 8))) {
+                        scr2_2 |= SCR2_RTDATA;
+                    }
+                    rtc_return = (rtc_return << 1) |
+                                 ((scr2_2 & SCR2_RTDATA) ? 1 : 0);
+                }
+
+            }
+
+            phase++;
+            if (phase == 16) {
+                if (rtc_command >= 0x80 && rtc_command <= 0x9F) {
+                    s->rtc_ram[rtc_command - 0x80] = rtc_value;
+#ifdef READ_RTC
+                    FILE *fp = fopen("rtc.ram", "wb+");
+                    int ret = fwrite(s->rtc_ram, 1, 32, fp);
+                    if (ret != 32) {
+                        abort();
+                    }
+                    fclose(fp);
+#endif
+                }
+                /* write to x30 register */
+                if (rtc_command == 0xB1) {
+                    /* clear FTU */
+                    if (rtc_value & 0x04) {
+                        rtc_status = rtc_status & (~0x18);
+                        s->int_status = s->int_status & (~0x04);
+                    }
+                }
+            }
+        }
+    } else {
+        /* else end or abort */
+        phase = -1;
+        rtc_command = 0;
+        rtc_value = 0;
+    }
+    s->scr2 = val & 0xFFFF00FF;
+    s->scr2 |= scr2_2 << 8;
+    old_scr2 = scr2_2;
+}
+
+static uint32_t mmio_readb(NeXTState *s, hwaddr addr)
+{
+    switch (addr) {
+    case 0xc000:
+        return (s->scr1 >> 24) & 0xFF;
+    case 0xc001:
+        return (s->scr1 >> 16) & 0xFF;
+    case 0xc002:
+        return (s->scr1 >> 8)  & 0xFF;
+    case 0xc003:
+        return (s->scr1 >> 0)  & 0xFF;
+
+    case 0xd000:
+        return (s->scr2 >> 24) & 0xFF;
+    case 0xd001:
+        return (s->scr2 >> 16) & 0xFF;
+    case 0xd002:
+        return (s->scr2 >> 8)  & 0xFF;
+    case 0xd003:
+        return (s->scr2 >> 0)  & 0xFF;
+    case 0x14020:
+        DPRINTF("MMIO Read 0x4020\n");
+        return 0x7f;
+
+    default:
+        DPRINTF("MMIO Read B @ %"HWADDR_PRIx"\n", addr);
+        return 0x0;
+    }
+}
+
+static uint32_t mmio_readw(NeXTState *s, hwaddr addr)
+{
+    switch (addr) {
+    default:
+        DPRINTF("MMIO Read W @ %"HWADDR_PRIx"\n", addr);
+        return 0x0;
+    }
+}
+
+static uint32_t mmio_readl(NeXTState *s, hwaddr addr)
+{
+    switch (addr) {
+    case 0x7000:
+        DPRINTF("Read INT status: %x\n", s->int_status);
+        return s->int_status;
+
+    case 0x7800:
+        DPRINTF("MMIO Read INT mask: %x\n", s->int_mask);
+        return s->int_mask;
+
+    case 0xc000:
+        return s->scr1;
+
+    /*
+     * case 0xc800:
+     *     return 0x01000000;
+     */
+
+    case 0xd000:
+        return s->scr2;
+
+    default:
+        DPRINTF("MMIO Read L @ %"HWADDR_PRIx"\n", addr);
+        return 0x0;
+    }
+}
+
+static void mmio_writeb(NeXTState *s, hwaddr addr, uint32_t val)
+{
+    switch (addr) {
+    case 0xd003:
+        nextscr2_write(s, val, 1);
+        break;
+    default:
+        DPRINTF("MMIO Write B @ %x with %x\n", (unsigned int)addr, val);
+    }
+
+}
+
+static void mmio_writew(NeXTState *s, hwaddr addr, uint32_t val)
+{
+    DPRINTF("MMIO Write W\n");
+}
+
+static void mmio_writel(NeXTState *s, hwaddr addr, uint32_t val)
+{
+    switch (addr) {
+    case 0x7000:
+        DPRINTF("INT Status old: %x new: %x\n", s->int_status, val);
+        s->int_status = val;
+        break;
+    case 0x7800:
+        DPRINTF("INT Mask old: %x new: %x\n", s->int_mask, val);
+        s->int_mask  = val;
+        break;
+    case 0xc000:
+        DPRINTF("SCR1 Write: %x\n", val);
+        break;
+    case 0xd000:
+        nextscr2_write(s, val, 4);
+        break;
+
+    default:
+        DPRINTF("MMIO Write l @ %x with %x\n", (unsigned int)addr, val);
+    }
+}
+
+static uint64_t mmio_readfn(void *opaque, hwaddr addr, unsigned size)
+{
+    NeXTState *ns = NEXT_MACHINE(opaque);
+
+    switch (size) {
+    case 1:
+        return mmio_readb(ns, addr);
+    case 2:
+        return mmio_readw(ns, addr);
+    case 4:
+        return mmio_readl(ns, addr);
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static void mmio_writefn(void *opaque, hwaddr addr, uint64_t value,
+                         unsigned size)
+{
+    NeXTState *ns = NEXT_MACHINE(opaque);
+
+    switch (size) {
+    case 1:
+        mmio_writeb(ns, addr, value);
+        break;
+    case 2:
+        mmio_writew(ns, addr, value);
+        break;
+    case 4:
+        mmio_writel(ns, addr, value);
+        break;
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static const MemoryRegionOps mmio_ops = {
+    .read = mmio_readfn,
+    .write = mmio_writefn,
+    .valid.min_access_size = 1,
+    .valid.max_access_size = 4,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static uint32_t scr_readb(NeXTState *s, hwaddr addr)
+{
+    switch (addr) {
+    case 0x14108:
+        DPRINTF("FD read @ %x\n", (unsigned int)addr);
+        return 0x40 | 0x04 | 0x2 | 0x1;
+    case 0x14020:
+        DPRINTF("SCSI 4020  STATUS READ %X\n", s->scsi_csr_1);
+        return s->scsi_csr_1;
+
+    case 0x14021:
+        DPRINTF("SCSI 4021 STATUS READ %X\n", s->scsi_csr_2);
+        return 0x40;
+
+    /*
+     * These 4 registers are the hardware timer, not sure which register
+     * is the latch instead of data, but no problems so far
+     */
+    case 0x1a000:
+        return 0xff & (clock() >> 24);
+    case 0x1a001:
+        return 0xff & (clock() >> 16);
+    case 0x1a002:
+        return 0xff & (clock() >> 8);
+    case 0x1a003:
+        /* Hack: We need to have this change consistently to make it work */
+        return 0xFF & clock();
+
+    default:
+        DPRINTF("BMAP Read B @ %x\n", (unsigned int)addr);
+        return 0;
+    }
+}
+
+static uint32_t scr_readw(NeXTState *s, hwaddr addr)
+{
+    DPRINTF("BMAP Read W @ %x\n", (unsigned int)addr);
+    return 0;
+}
+
+static uint32_t scr_readl(NeXTState *s, hwaddr addr)
+{
+    DPRINTF("BMAP Read L @ %x\n", (unsigned int)addr);
+    return 0;
+}
+
+#define SCSICSR_ENABLE  0x01
+#define SCSICSR_RESET   0x02  /* reset scsi dma */
+#define SCSICSR_FIFOFL  0x04
+#define SCSICSR_DMADIR  0x08  /* if set, scsi to mem */
+#define SCSICSR_CPUDMA  0x10  /* if set, dma enabled */
+#define SCSICSR_INTMASK 0x20  /* if set, interrupt enabled */
+
+static void scr_writeb(NeXTState *s, hwaddr addr, uint32_t value)
+{
+    switch (addr) {
+    case 0x14108:
+        DPRINTF("FDCSR Write: %x\n", value);
+
+        if (value == 0x0) {
+            /* qemu_irq_raise(s->fd_irq[0]); */
+        }
+        break;
+    case 0x14020: /* SCSI Control Register */
+        if (value & SCSICSR_FIFOFL) {
+            DPRINTF("SCSICSR FIFO Flush\n");
+            /* will have to add another irq to the esp if this is needed */
+            /* esp_puflush_fifo(esp_g); */
+            /* qemu_irq_pulse(s->scsi_dma); */
+        }
+
+        if (value & SCSICSR_ENABLE) {
+            DPRINTF("SCSICSR Enable\n");
+            /*
+             * qemu_irq_raise(s->scsi_dma);
+             * s->scsi_csr_1 = 0xc0;
+             * s->scsi_csr_1 |= 0x1;
+             * qemu_irq_pulse(s->scsi_dma);
+             */
+        }
+        /*
+         * else
+         *     s->scsi_csr_1 &= ~SCSICSR_ENABLE;
+         */
+
+        if (value & SCSICSR_RESET) {
+            DPRINTF("SCSICSR Reset\n");
+            /* I think this should set DMADIR. CPUDMA and INTMASK to 0 */
+            /* qemu_irq_raise(s->scsi_reset); */
+            /* s->scsi_csr_1 &= ~(SCSICSR_INTMASK |0x80|0x1); */
+
+        }
+        if (value & SCSICSR_DMADIR) {
+            DPRINTF("SCSICSR DMAdir\n");
+        }
+        if (value & SCSICSR_CPUDMA) {
+            DPRINTF("SCSICSR CPUDMA\n");
+            /* qemu_irq_raise(s->scsi_dma); */
+
+            s->int_status |= 0x4000000;
+        } else {
+            s->int_status &= ~(0x4000000);
+        }
+        if (value & SCSICSR_INTMASK) {
+            DPRINTF("SCSICSR INTMASK\n");
+            /*
+             * int_mask &= ~0x1000;
+             * s->scsi_csr_1 |= value;
+             * s->scsi_csr_1 &= ~SCSICSR_INTMASK;
+             * if (s->scsi_queued) {
+             *     s->scsi_queued = 0;
+             *     next_irq(s, NEXT_SCSI_I, level);
+             * }
+             */
+        } else {
+            /* int_mask |= 0x1000; */
+        }
+        if (value & 0x80) {
+            /* int_mask |= 0x1000; */
+            /* s->scsi_csr_1 |= 0x80; */
+        }
+        DPRINTF("SCSICSR Write: %x\n", value);
+        /* s->scsi_csr_1 = value; */
+        return;
+    /* Hardware timer latch - not implemented yet */
+    case 0x1a000:
+    default:
+        DPRINTF("BMAP Write B @ %x with %x\n", (unsigned int)addr, value);
+    }
+}
+
+static void scr_writew(NeXTState *s, hwaddr addr, uint32_t value)
+{
+    DPRINTF("BMAP Write W @ %x with %x\n", (unsigned int)addr, value);
+}
+
+static void scr_writel(NeXTState *s, hwaddr addr, uint32_t value)
+{
+    DPRINTF("BMAP Write L @ %x with %x\n", (unsigned int)addr, value);
+}
+
+static uint64_t scr_readfn(void *opaque, hwaddr addr, unsigned size)
+{
+    NeXTState *ns = NEXT_MACHINE(opaque);
+
+    switch (size) {
+    case 1:
+        return scr_readb(ns, addr);
+    case 2:
+        return scr_readw(ns, addr);
+    case 4:
+        return scr_readl(ns, addr);
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static void scr_writefn(void *opaque, hwaddr addr, uint64_t value,
+                        unsigned size)
+{
+    NeXTState *ns = NEXT_MACHINE(opaque);
+
+    switch (size) {
+    case 1:
+        scr_writeb(ns, addr, value);
+        break;
+    case 2:
+        scr_writew(ns, addr, value);
+        break;
+    case 4:
+        scr_writel(ns, addr, value);
+        break;
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static const MemoryRegionOps scr_ops = {
+    .read = scr_readfn,
+    .write = scr_writefn,
+    .valid.min_access_size = 1,
+    .valid.max_access_size = 4,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+#define NEXTDMA_SCSI(x)      (0x10 + x)
+#define NEXTDMA_FD(x)        (0x10 + x)
+#define NEXTDMA_ENTX(x)      (0x110 + x)
+#define NEXTDMA_ENRX(x)      (0x150 + x)
+#define NEXTDMA_CSR          0x0
+#define NEXTDMA_SAVED_NEXT   0x3FF0
+#define NEXTDMA_SAVED_LIMIT  0x3FF4
+#define NEXTDMA_SAVED_START  0x3FF8
+#define NEXTDMA_SAVED_STOP   0x3FFc
+#define NEXTDMA_NEXT         0x4000
+#define NEXTDMA_LIMIT        0x4004
+#define NEXTDMA_START        0x4008
+#define NEXTDMA_STOP         0x400c
+#define NEXTDMA_NEXT_INIT    0x4200
+#define NEXTDMA_SIZE         0x4204
+
+static void dma_writel(void *opaque, hwaddr addr, uint64_t value,
+                       unsigned int size)
+{
+    NeXTState *next_state = NEXT_MACHINE(opaque);
+
+    /*
+     * uint16_t reg = addr;
+     * int channel = 0;
+     * switch (reg) {
+     * case SCSI"all registers:
+     *     channel = NEXTDMA_SCSI;
+     *     addr = addr - NEXTDMA_SCSI(0);
+     * }
+     */
+
+    switch (addr) {
+    case NEXTDMA_ENRX(NEXTDMA_CSR):
+        if (value & DMA_DEV2M) {
+            next_state->dma[NEXTDMA_ENRX].csr |= DMA_DEV2M;
+        }
+
+        if (value & DMA_SETENABLE) {
+            /* DPRINTF("SCSI DMA ENABLE\n"); */
+            next_state->dma[NEXTDMA_ENRX].csr |= DMA_ENABLE;
+            /*
+             * if (!(next_state->dma[NEXTDMA_ENRX].csr & DMA_DEV2M))
+             *  DPRINTF("DMA TO DEVICE\n");
+             * else
+             *  DPRINTF("DMA TO CPU\n");
+             * if (next_state->scsi_csr_1 & 1<<3)
+             *  DPRINTF("SCSI DIR\n");
+             */
+        }
+        if (value & DMA_SETSUPDATE) {
+            next_state->dma[NEXTDMA_ENRX].csr |= DMA_SUPDATE;
+        }
+        if (value & DMA_CLRCOMPLETE) {
+            next_state->dma[NEXTDMA_ENRX].csr &= ~DMA_COMPLETE;
+        }
+
+        if (value & DMA_RESET) {
+            next_state->dma[NEXTDMA_ENRX].csr &= ~(DMA_COMPLETE | DMA_SUPDATE |
+                                                  DMA_ENABLE | DMA_DEV2M);
+        }
+        /* DPRINTF("RXCSR \tWrite: %x\n",value); */
+        break;
+    case NEXTDMA_ENRX(NEXTDMA_NEXT_INIT):
+        next_state->dma[NEXTDMA_ENRX].next_initbuf = value;
+        break;
+    case NEXTDMA_ENRX(NEXTDMA_NEXT):
+        next_state->dma[NEXTDMA_ENRX].next = value;
+        break;
+    case NEXTDMA_ENRX(NEXTDMA_LIMIT):
+        next_state->dma[NEXTDMA_ENRX].limit = value;
+        break;
+    case NEXTDMA_SCSI(NEXTDMA_CSR):
+        if (value & DMA_DEV2M) {
+            next_state->dma[NEXTDMA_SCSI].csr |= DMA_DEV2M;
+        }
+        if (value & DMA_SETENABLE) {
+            /* DPRINTF("SCSI DMA ENABLE\n"); */
+            next_state->dma[NEXTDMA_SCSI].csr |= DMA_ENABLE;
+            /*
+             * if (!(next_state->dma[NEXTDMA_SCSI].csr & DMA_DEV2M)) {
+             *    DPRINTF("DMA TO DEVICE\n");
+             * } else {
+             *    DPRINTF("DMA TO CPU\n");
+             * }
+             * if (next_state->scsi_csr_1 & 1<<3) {
+             *     DPRINTF("SCSI DIR\n");
+             * }
+             */
+        }
+        if (value & DMA_SETSUPDATE) {
+            next_state->dma[NEXTDMA_SCSI].csr |= DMA_SUPDATE;
+        }
+        if (value & DMA_CLRCOMPLETE) {
+            next_state->dma[NEXTDMA_SCSI].csr &= ~DMA_COMPLETE;
+        }
+
+        if (value & DMA_RESET) {
+            next_state->dma[NEXTDMA_SCSI].csr &= ~(DMA_COMPLETE | DMA_SUPDATE |
+                                                  DMA_ENABLE | DMA_DEV2M);
+            /* DPRINTF("SCSI DMA RESET\n"); */
+        }
+        /* DPRINTF("RXCSR \tWrite: %x\n",value); */
+        break;
+
+    case NEXTDMA_SCSI(NEXTDMA_NEXT):
+        next_state->dma[NEXTDMA_SCSI].next = value;
+        break;
+
+    case NEXTDMA_SCSI(NEXTDMA_LIMIT):
+        next_state->dma[NEXTDMA_SCSI].limit = value;
+        break;
+
+    case NEXTDMA_SCSI(NEXTDMA_START):
+        next_state->dma[NEXTDMA_SCSI].start = value;
+        break;
+
+    case NEXTDMA_SCSI(NEXTDMA_STOP):
+        next_state->dma[NEXTDMA_SCSI].stop = value;
+        break;
+
+    case NEXTDMA_SCSI(NEXTDMA_NEXT_INIT):
+        next_state->dma[NEXTDMA_SCSI].next_initbuf = value;
+        break;
+
+    default:
+        DPRINTF("DMA write @ %x w/ %x\n", (unsigned int)addr, value);
+    }
+}
+
+static uint64_t dma_readl(void *opaque, hwaddr addr, unsigned int size)
+{
+    NeXTState *next_state = NEXT_MACHINE(opaque);
+
+    switch (addr) {
+    case NEXTDMA_SCSI(NEXTDMA_CSR):
+        DPRINTF("SCSI DMA CSR READ\n");
+        return next_state->dma[NEXTDMA_SCSI].csr;
+    case NEXTDMA_ENRX(NEXTDMA_CSR):
+        return next_state->dma[NEXTDMA_ENRX].csr;
+    case NEXTDMA_ENRX(NEXTDMA_NEXT_INIT):
+        return next_state->dma[NEXTDMA_ENRX].next_initbuf;
+    case NEXTDMA_ENRX(NEXTDMA_NEXT):
+        return next_state->dma[NEXTDMA_ENRX].next;
+    case NEXTDMA_ENRX(NEXTDMA_LIMIT):
+        return next_state->dma[NEXTDMA_ENRX].limit;
+
+    case NEXTDMA_SCSI(NEXTDMA_NEXT):
+        return next_state->dma[NEXTDMA_SCSI].next;
+    case NEXTDMA_SCSI(NEXTDMA_NEXT_INIT):
+        return next_state->dma[NEXTDMA_SCSI].next_initbuf;
+    case NEXTDMA_SCSI(NEXTDMA_LIMIT):
+        return next_state->dma[NEXTDMA_SCSI].limit;
+    case NEXTDMA_SCSI(NEXTDMA_START):
+        return next_state->dma[NEXTDMA_SCSI].start;
+    case NEXTDMA_SCSI(NEXTDMA_STOP):
+        return next_state->dma[NEXTDMA_SCSI].stop;
+
+    default:
+        DPRINTF("DMA read @ %x\n", (unsigned int)addr);
+        return 0;
+    }
+
+    /*
+     * once the csr's are done, subtract 0x3FEC from the addr, and that will
+     * normalize the upper registers
+     */
+}
+
+static const MemoryRegionOps dma_ops = {
+    .read = dma_readl,
+    .write = dma_writel,
+    .impl.min_access_size = 4,
+    .valid.min_access_size = 4,
+    .valid.max_access_size = 4,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+/*
+ * TODO: set the shift numbers as values in the enum, so the first switch
+ * will not be needed
+ */
+void next_irq(void *opaque, int number, int level)
+{
+    M68kCPU *cpu = opaque;
+    int shift = 0;
+    NeXTState *ns = NEXT_MACHINE(qdev_get_machine());
+
+    /* first switch sets interupt status */
+    /* DPRINTF("IRQ %i\n",number); */
+    switch (number) {
+    /* level 3 - floppy, kbd/mouse, power, ether rx/tx, scsi, clock */
+    case NEXT_FD_I:
+        shift = 7;;
+        break;
+    case NEXT_KBD_I:
+        shift = 3;
+        break;
+    case NEXT_PWR_I:
+        shift = 2;
+        break;
+    case NEXT_ENRX_I:
+        shift = 9;
+        break;
+    case NEXT_ENTX_I:
+        shift = 10;
+        break;
+    case NEXT_SCSI_I:
+        shift = 12;
+        break;
+    case NEXT_CLK_I:
+        shift = 5;
+        break;
+
+    /* level 5 - scc (serial) */
+    case NEXT_SCC_I:
+        shift = 17;
+        break;
+
+    /* level 6 - audio etherrx/tx dma */
+    case NEXT_ENTX_DMA_I:
+        shift = 28;
+        break;
+    case NEXT_ENRX_DMA_I:
+        shift = 27;
+        break;
+    case NEXT_SCSI_DMA_I:
+        shift = 26;
+        break;
+    case NEXT_SND_I:
+        shift = 23;
+        break;
+    case NEXT_SCC_DMA_I:
+        shift = 21;
+        break;
+
+    }
+    /*
+     * this HAS to be wrong, the interrupt handlers in mach and together
+     * int_status and int_mask and return if there is a hit
+     */
+    if (ns->int_mask & (1 << shift)) {
+        DPRINTF("%x interrupt masked @ %x\n", 1 << shift, cpu->env.pc);
+        /* return; */
+    }
+
+    /* second switch triggers the correct interrupt */
+    if (level) {
+        ns->int_status |= 1 << shift;
+
+        switch (number) {
+        /* level 3 - floppy, kbd/mouse, power, ether rx/tx, scsi, clock */
+        case NEXT_FD_I:
+        case NEXT_KBD_I:
+        case NEXT_PWR_I:
+        case NEXT_ENRX_I:
+        case NEXT_ENTX_I:
+        case NEXT_SCSI_I:
+        case NEXT_CLK_I:
+            m68k_set_irq_level(cpu, 3, 27);
+            break;
+
+        /* level 5 - scc (serial) */
+        case NEXT_SCC_I:
+            m68k_set_irq_level(cpu, 5, 29);
+            break;
+
+        /* level 6 - audio etherrx/tx dma */
+        case NEXT_ENTX_DMA_I:
+        case NEXT_ENRX_DMA_I:
+        case NEXT_SCSI_DMA_I:
+        case NEXT_SND_I:
+        case NEXT_SCC_DMA_I:
+            m68k_set_irq_level(cpu, 6, 30);
+            break;
+        }
+    } else {
+        ns->int_status &= ~(1 << shift);
+        cpu_reset_interrupt(CPU(cpu), CPU_INTERRUPT_HARD);
+    }
+}
+
+static void next_cube_init(MachineState *machine)
+{
+    M68kCPU *cpu;
+    CPUM68KState *env;
+    MemoryRegion *ram = g_new(MemoryRegion, 1);
+    MemoryRegion *rom = g_new(MemoryRegion, 1);
+    MemoryRegion *mmiomem = g_new(MemoryRegion, 1);
+    MemoryRegion *scrmem = g_new(MemoryRegion, 1);
+    MemoryRegion *dmamem = g_new(MemoryRegion, 1);
+    MemoryRegion *aliasmem = g_new(MemoryRegion, 1);
+    MemoryRegion *sysmem = get_system_memory();
+    NeXTState *ns = NEXT_MACHINE(machine);
+    DeviceState *dev;
+
+    /* Initialize the cpu core */
+    cpu = M68K_CPU(cpu_create(machine->cpu_type));
+    if (!cpu) {
+        error_report("Unable to find m68k CPU definition");
+        exit(1);
+    }
+    env = &cpu->env;
+
+    /* Initialize CPU registers.  */
+    env->vbr = 0;
+    env->pc  = 0x100001e; /* technically should read vector */
+    env->sr  = 0x2700;
+
+    /* Set internal registers to initial values */
+    /*     0x0000XX00 << vital bits */
+    ns->scr1 = 0x00011102;
+    ns->scr2 = 0x00ff0c80;
+
+    /* Load RTC RAM - TODO: provide possibility to load contents from file */
+    memcpy(ns->rtc_ram, rtc_ram2, 32);
+
+    /* 64MB RAM starting at 0x04000000  */
+    memory_region_allocate_system_memory(ram, NULL, "next.ram", ram_size);
+    memory_region_add_subregion(sysmem, 0x04000000, ram);
+
+    /* The Rev_2.5_v66.bin firmware accesses the MMIO at 0x820c0020, too */
+    memory_region_init_alias(aliasmem, NULL,"next.unknown", mmiomem, 0xc0020,
+                             16);
+    memory_region_add_subregion(sysmem, 0x820c0020, aliasmem);
+
+    /* Framebuffer */
+    dev = qdev_create(NULL, TYPE_NEXTFB);
+    qdev_init_nofail(dev);
+    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 0x0B000000);
+
+    /* MMIO */
+    memory_region_init_io(mmiomem, NULL, &mmio_ops, machine, "next.mmio",
+                          0xD0000);
+    memory_region_add_subregion(sysmem, 0x02000000, mmiomem);
+
+    /* BMAP - acts as a catch-all for now */
+    memory_region_init_io(scrmem, NULL, &scr_ops, machine, "next.scr",
+                          0x20000);
+    memory_region_add_subregion(sysmem, 0x02100000, scrmem);
+
+    /* KBD */
+    dev = qdev_create(NULL, TYPE_NEXTKBD);
+    qdev_init_nofail(dev);
+    sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, 0x0200e000);
+
+    /* Load ROM here */
+    if (bios_name == NULL) {
+        bios_name = ROM_FILE;
+    }
+    /* still not sure if the rom should also be mapped at 0x0*/
+    memory_region_init_rom(rom, NULL, "next.rom", 0x20000, &error_fatal);
+    memory_region_add_subregion(sysmem, 0x01000000, rom);
+    if (load_image_targphys(bios_name, 0x01000000, 0x20000) < 0) {
+        if (!qtest_enabled()) {
+            error_report("Failed to load firmware '%s'", bios_name);
+        }
+    }
+
+    /* TODO: */
+    /* Serial */
+    /* Network */
+    /* SCSI */
+
+    /* DMA */
+    memory_region_init_io(dmamem, NULL, &dma_ops, machine, "next.dma", 0x5000);
+    memory_region_add_subregion(sysmem, 0x02000000, dmamem);
+}
+
+static void next_machine_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+
+    mc->desc = "NeXT Cube";
+    mc->init = next_cube_init;
+    mc->default_ram_size = RAM_SIZE;
+    mc->default_cpu_type = M68K_CPU_TYPE_NAME("m68040");
+}
+
+static const TypeInfo next_typeinfo = {
+    .name = TYPE_NEXT_MACHINE,
+    .parent = TYPE_MACHINE,
+    .class_init = next_machine_class_init,
+    .instance_size = sizeof(NeXTState),
+};
+
+static void next_register_type(void)
+{
+    type_register_static(&next_typeinfo);
+}
+
+type_init(next_register_type)
diff --git a/include/hw/m68k/next-cube.h b/include/hw/m68k/next-cube.h
index 37f7ce3e34..a3be2b32ab 100644
--- a/include/hw/m68k/next-cube.h
+++ b/include/hw/m68k/next-cube.h
@@ -6,4 +6,42 @@ 
 
 #define TYPE_NEXTKBD "next-kbd"
 
+enum next_dma_chan {
+    NEXTDMA_FD,
+    NEXTDMA_ENRX,
+    NEXTDMA_ENTX,
+    NEXTDMA_SCSI,
+    NEXTDMA_SCC,
+    NEXTDMA_SND
+};
+
+#define DMA_ENABLE      0x01000000
+#define DMA_SUPDATE     0x02000000
+#define DMA_COMPLETE    0x08000000
+
+#define DMA_M2DEV       0x0
+#define DMA_SETENABLE   0x00010000
+#define DMA_SETSUPDATE  0x00020000
+#define DMA_DEV2M       0x00040000
+#define DMA_CLRCOMPLETE 0x00080000
+#define DMA_RESET       0x00100000
+
+enum next_irqs {
+    NEXT_FD_I,
+    NEXT_KBD_I,
+    NEXT_PWR_I,
+    NEXT_ENRX_I,
+    NEXT_ENTX_I,
+    NEXT_SCSI_I,
+    NEXT_CLK_I,
+    NEXT_SCC_I,
+    NEXT_ENTX_DMA_I,
+    NEXT_ENRX_DMA_I,
+    NEXT_SCSI_DMA_I,
+    NEXT_SCC_DMA_I,
+    NEXT_SND_I
+};
+
+void next_irq(void *opaque, int number, int level);
+
 #endif /* NEXT_CUBE_H */