Add qemu 2.4.0

Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5
Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>

1 files changed, 768 insertions, 0 deletions

diff --git a/qemu/hw/misc/macio/mac_dbdma.c b/qemu/hw/misc/macio/mac_dbdma.c
new file mode 100644
index 000000000..b25e8511b
--- /dev/null
+++ b/qemu/hw/misc/macio/mac_dbdma.c
@@ -0,0 +1,768 @@
+/*
+ * PowerMac descriptor-based DMA emulation
+ *
+ * Copyright (c) 2005-2007 Fabrice Bellard
+ * Copyright (c) 2007 Jocelyn Mayer
+ * Copyright (c) 2009 Laurent Vivier
+ *
+ * some parts from linux-2.6.28, arch/powerpc/include/asm/dbdma.h
+ *
+ *   Definitions for using the Apple Descriptor-Based DMA controller
+ *   in Power Macintosh computers.
+ *
+ *   Copyright (C) 1996 Paul Mackerras.
+ *
+ * some parts from mol 0.9.71
+ *
+ *   Descriptor based DMA emulation
+ *
+ *   Copyright (C) 1998-2004 Samuel Rydh (samuel@ibrium.se)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "hw/hw.h"
+#include "hw/isa/isa.h"
+#include "hw/ppc/mac_dbdma.h"
+#include "qemu/main-loop.h"
+
+/* debug DBDMA */
+//#define DEBUG_DBDMA
+
+#ifdef DEBUG_DBDMA
+#define DBDMA_DPRINTF(fmt, ...)                                 \
+    do { printf("DBDMA: " fmt , ## __VA_ARGS__); } while (0)
+#else
+#define DBDMA_DPRINTF(fmt, ...)
+#endif
+
+/*
+ */
+
+static DBDMAState *dbdma_from_ch(DBDMA_channel *ch)
+{
+    return container_of(ch, DBDMAState, channels[ch->channel]);
+}
+
+#ifdef DEBUG_DBDMA
+static void dump_dbdma_cmd(dbdma_cmd *cmd)
+{
+    printf("dbdma_cmd %p\n", cmd);
+    printf("    req_count 0x%04x\n", le16_to_cpu(cmd->req_count));
+    printf("    command 0x%04x\n", le16_to_cpu(cmd->command));
+    printf("    phy_addr 0x%08x\n", le32_to_cpu(cmd->phy_addr));
+    printf("    cmd_dep 0x%08x\n", le32_to_cpu(cmd->cmd_dep));
+    printf("    res_count 0x%04x\n", le16_to_cpu(cmd->res_count));
+    printf("    xfer_status 0x%04x\n", le16_to_cpu(cmd->xfer_status));
+}
+#else
+static void dump_dbdma_cmd(dbdma_cmd *cmd)
+{
+}
+#endif
+static void dbdma_cmdptr_load(DBDMA_channel *ch)
+{
+    DBDMA_DPRINTF("dbdma_cmdptr_load 0x%08x\n",
+                  ch->regs[DBDMA_CMDPTR_LO]);
+    cpu_physical_memory_read(ch->regs[DBDMA_CMDPTR_LO],
+                             &ch->current, sizeof(dbdma_cmd));
+}
+
+static void dbdma_cmdptr_save(DBDMA_channel *ch)
+{
+    DBDMA_DPRINTF("dbdma_cmdptr_save 0x%08x\n",
+                  ch->regs[DBDMA_CMDPTR_LO]);
+    DBDMA_DPRINTF("xfer_status 0x%08x res_count 0x%04x\n",
+                  le16_to_cpu(ch->current.xfer_status),
+                  le16_to_cpu(ch->current.res_count));
+    cpu_physical_memory_write(ch->regs[DBDMA_CMDPTR_LO],
+                              &ch->current, sizeof(dbdma_cmd));
+}
+
+static void kill_channel(DBDMA_channel *ch)
+{
+    DBDMA_DPRINTF("kill_channel\n");
+
+    ch->regs[DBDMA_STATUS] |= DEAD;
+    ch->regs[DBDMA_STATUS] &= ~ACTIVE;
+
+    qemu_irq_raise(ch->irq);
+}
+
+static void conditional_interrupt(DBDMA_channel *ch)
+{
+    dbdma_cmd *current = &ch->current;
+    uint16_t intr;
+    uint16_t sel_mask, sel_value;
+    uint32_t status;
+    int cond;
+
+    DBDMA_DPRINTF("%s\n", __func__);
+
+    intr = le16_to_cpu(current->command) & INTR_MASK;
+
+    switch(intr) {
+    case INTR_NEVER:  /* don't interrupt */
+        return;
+    case INTR_ALWAYS: /* always interrupt */
+        qemu_irq_raise(ch->irq);
+        DBDMA_DPRINTF("%s: raise\n", __func__);
+        return;
+    }
+
+    status = ch->regs[DBDMA_STATUS] & DEVSTAT;
+
+    sel_mask = (ch->regs[DBDMA_INTR_SEL] >> 16) & 0x0f;
+    sel_value = ch->regs[DBDMA_INTR_SEL] & 0x0f;
+
+    cond = (status & sel_mask) == (sel_value & sel_mask);
+
+    switch(intr) {
+    case INTR_IFSET:  /* intr if condition bit is 1 */
+        if (cond) {
+            qemu_irq_raise(ch->irq);
+            DBDMA_DPRINTF("%s: raise\n", __func__);
+        }
+        return;
+    case INTR_IFCLR:  /* intr if condition bit is 0 */
+        if (!cond) {
+            qemu_irq_raise(ch->irq);
+            DBDMA_DPRINTF("%s: raise\n", __func__);
+        }
+        return;
+    }
+}
+
+static int conditional_wait(DBDMA_channel *ch)
+{
+    dbdma_cmd *current = &ch->current;
+    uint16_t wait;
+    uint16_t sel_mask, sel_value;
+    uint32_t status;
+    int cond;
+
+    DBDMA_DPRINTF("conditional_wait\n");
+
+    wait = le16_to_cpu(current->command) & WAIT_MASK;
+
+    switch(wait) {
+    case WAIT_NEVER:  /* don't wait */
+        return 0;
+    case WAIT_ALWAYS: /* always wait */
+        return 1;
+    }
+
+    status = ch->regs[DBDMA_STATUS] & DEVSTAT;
+
+    sel_mask = (ch->regs[DBDMA_WAIT_SEL] >> 16) & 0x0f;
+    sel_value = ch->regs[DBDMA_WAIT_SEL] & 0x0f;
+
+    cond = (status & sel_mask) == (sel_value & sel_mask);
+
+    switch(wait) {
+    case WAIT_IFSET:  /* wait if condition bit is 1 */
+        if (cond)
+            return 1;
+        return 0;
+    case WAIT_IFCLR:  /* wait if condition bit is 0 */
+        if (!cond)
+            return 1;
+        return 0;
+    }
+    return 0;
+}
+
+static void next(DBDMA_channel *ch)
+{
+    uint32_t cp;
+
+    ch->regs[DBDMA_STATUS] &= ~BT;
+
+    cp = ch->regs[DBDMA_CMDPTR_LO];
+    ch->regs[DBDMA_CMDPTR_LO] = cp + sizeof(dbdma_cmd);
+    dbdma_cmdptr_load(ch);
+}
+
+static void branch(DBDMA_channel *ch)
+{
+    dbdma_cmd *current = &ch->current;
+
+    ch->regs[DBDMA_CMDPTR_LO] = current->cmd_dep;
+    ch->regs[DBDMA_STATUS] |= BT;
+    dbdma_cmdptr_load(ch);
+}
+
+static void conditional_branch(DBDMA_channel *ch)
+{
+    dbdma_cmd *current = &ch->current;
+    uint16_t br;
+    uint16_t sel_mask, sel_value;
+    uint32_t status;
+    int cond;
+
+    DBDMA_DPRINTF("conditional_branch\n");
+
+    /* check if we must branch */
+
+    br = le16_to_cpu(current->command) & BR_MASK;
+
+    switch(br) {
+    case BR_NEVER:  /* don't branch */
+        next(ch);
+        return;
+    case BR_ALWAYS: /* always branch */
+        branch(ch);
+        return;
+    }
+
+    status = ch->regs[DBDMA_STATUS] & DEVSTAT;
+
+    sel_mask = (ch->regs[DBDMA_BRANCH_SEL] >> 16) & 0x0f;
+    sel_value = ch->regs[DBDMA_BRANCH_SEL] & 0x0f;
+
+    cond = (status & sel_mask) == (sel_value & sel_mask);
+
+    switch(br) {
+    case BR_IFSET:  /* branch if condition bit is 1 */
+        if (cond)
+            branch(ch);
+        else
+            next(ch);
+        return;
+    case BR_IFCLR:  /* branch if condition bit is 0 */
+        if (!cond)
+            branch(ch);
+        else
+            next(ch);
+        return;
+    }
+}
+
+static void channel_run(DBDMA_channel *ch);
+
+static void dbdma_end(DBDMA_io *io)
+{
+    DBDMA_channel *ch = io->channel;
+    dbdma_cmd *current = &ch->current;
+
+    DBDMA_DPRINTF("%s\n", __func__);
+
+    if (conditional_wait(ch))
+        goto wait;
+
+    current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
+    current->res_count = cpu_to_le16(io->len);
+    dbdma_cmdptr_save(ch);
+    if (io->is_last)
+        ch->regs[DBDMA_STATUS] &= ~FLUSH;
+
+    conditional_interrupt(ch);
+    conditional_branch(ch);
+
+wait:
+    /* Indicate that we're ready for a new DMA round */
+    ch->io.processing = false;
+
+    if ((ch->regs[DBDMA_STATUS] & RUN) &&
+        (ch->regs[DBDMA_STATUS] & ACTIVE))
+        channel_run(ch);
+}
+
+static void start_output(DBDMA_channel *ch, int key, uint32_t addr,
+                        uint16_t req_count, int is_last)
+{
+    DBDMA_DPRINTF("start_output\n");
+
+    /* KEY_REGS, KEY_DEVICE and KEY_STREAM
+     * are not implemented in the mac-io chip
+     */
+
+    DBDMA_DPRINTF("addr 0x%x key 0x%x\n", addr, key);
+    if (!addr || key > KEY_STREAM3) {
+        kill_channel(ch);
+        return;
+    }
+
+    ch->io.addr = addr;
+    ch->io.len = req_count;
+    ch->io.is_last = is_last;
+    ch->io.dma_end = dbdma_end;
+    ch->io.is_dma_out = 1;
+    ch->io.processing = true;
+    if (ch->rw) {
+        ch->rw(&ch->io);
+    }
+}
+
+static void start_input(DBDMA_channel *ch, int key, uint32_t addr,
+                       uint16_t req_count, int is_last)
+{
+    DBDMA_DPRINTF("start_input\n");
+
+    /* KEY_REGS, KEY_DEVICE and KEY_STREAM
+     * are not implemented in the mac-io chip
+     */
+
+    DBDMA_DPRINTF("addr 0x%x key 0x%x\n", addr, key);
+    if (!addr || key > KEY_STREAM3) {
+        kill_channel(ch);
+        return;
+    }
+
+    ch->io.addr = addr;
+    ch->io.len = req_count;
+    ch->io.is_last = is_last;
+    ch->io.dma_end = dbdma_end;
+    ch->io.is_dma_out = 0;
+    ch->io.processing = true;
+    if (ch->rw) {
+        ch->rw(&ch->io);
+    }
+}
+
+static void load_word(DBDMA_channel *ch, int key, uint32_t addr,
+                     uint16_t len)
+{
+    dbdma_cmd *current = &ch->current;
+    uint32_t val;
+
+    DBDMA_DPRINTF("load_word\n");
+
+    /* only implements KEY_SYSTEM */
+
+    if (key != KEY_SYSTEM) {
+        printf("DBDMA: LOAD_WORD, unimplemented key %x\n", key);
+        kill_channel(ch);
+        return;
+    }
+
+    cpu_physical_memory_read(addr, &val, len);
+
+    if (len == 2)
+        val = (val << 16) | (current->cmd_dep & 0x0000ffff);
+    else if (len == 1)
+        val = (val << 24) | (current->cmd_dep & 0x00ffffff);
+
+    current->cmd_dep = val;
+
+    if (conditional_wait(ch))
+        goto wait;
+
+    current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
+    dbdma_cmdptr_save(ch);
+    ch->regs[DBDMA_STATUS] &= ~FLUSH;
+
+    conditional_interrupt(ch);
+    next(ch);
+
+wait:
+    DBDMA_kick(dbdma_from_ch(ch));
+}
+
+static void store_word(DBDMA_channel *ch, int key, uint32_t addr,
+                      uint16_t len)
+{
+    dbdma_cmd *current = &ch->current;
+    uint32_t val;
+
+    DBDMA_DPRINTF("store_word\n");
+
+    /* only implements KEY_SYSTEM */
+
+    if (key != KEY_SYSTEM) {
+        printf("DBDMA: STORE_WORD, unimplemented key %x\n", key);
+        kill_channel(ch);
+        return;
+    }
+
+    val = current->cmd_dep;
+    if (len == 2)
+        val >>= 16;
+    else if (len == 1)
+        val >>= 24;
+
+    cpu_physical_memory_write(addr, &val, len);
+
+    if (conditional_wait(ch))
+        goto wait;
+
+    current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
+    dbdma_cmdptr_save(ch);
+    ch->regs[DBDMA_STATUS] &= ~FLUSH;
+
+    conditional_interrupt(ch);
+    next(ch);
+
+wait:
+    DBDMA_kick(dbdma_from_ch(ch));
+}
+
+static void nop(DBDMA_channel *ch)
+{
+    dbdma_cmd *current = &ch->current;
+
+    if (conditional_wait(ch))
+        goto wait;
+
+    current->xfer_status = cpu_to_le16(ch->regs[DBDMA_STATUS]);
+    dbdma_cmdptr_save(ch);
+
+    conditional_interrupt(ch);
+    conditional_branch(ch);
+
+wait:
+    DBDMA_kick(dbdma_from_ch(ch));
+}
+
+static void stop(DBDMA_channel *ch)
+{
+    ch->regs[DBDMA_STATUS] &= ~(ACTIVE|DEAD|FLUSH);
+
+    /* the stop command does not increment command pointer */
+}
+
+static void channel_run(DBDMA_channel *ch)
+{
+    dbdma_cmd *current = &ch->current;
+    uint16_t cmd, key;
+    uint16_t req_count;
+    uint32_t phy_addr;
+
+    DBDMA_DPRINTF("channel_run\n");
+    dump_dbdma_cmd(current);
+
+    /* clear WAKE flag at command fetch */
+
+    ch->regs[DBDMA_STATUS] &= ~WAKE;
+
+    cmd = le16_to_cpu(current->command) & COMMAND_MASK;
+
+    switch (cmd) {
+    case DBDMA_NOP:
+        nop(ch);
+        return;
+
+    case DBDMA_STOP:
+        stop(ch);
+        return;
+    }
+
+    key = le16_to_cpu(current->command) & 0x0700;
+    req_count = le16_to_cpu(current->req_count);
+    phy_addr = le32_to_cpu(current->phy_addr);
+
+    if (key == KEY_STREAM4) {
+        printf("command %x, invalid key 4\n", cmd);
+        kill_channel(ch);
+        return;
+    }
+
+    switch (cmd) {
+    case OUTPUT_MORE:
+        start_output(ch, key, phy_addr, req_count, 0);
+        return;
+
+    case OUTPUT_LAST:
+        start_output(ch, key, phy_addr, req_count, 1);
+        return;
+
+    case INPUT_MORE:
+        start_input(ch, key, phy_addr, req_count, 0);
+        return;
+
+    case INPUT_LAST:
+        start_input(ch, key, phy_addr, req_count, 1);
+        return;
+    }
+
+    if (key < KEY_REGS) {
+        printf("command %x, invalid key %x\n", cmd, key);
+        key = KEY_SYSTEM;
+    }
+
+    /* for LOAD_WORD and STORE_WORD, req_count is on 3 bits
+     * and BRANCH is invalid
+     */
+
+    req_count = req_count & 0x0007;
+    if (req_count & 0x4) {
+        req_count = 4;
+        phy_addr &= ~3;
+    } else if (req_count & 0x2) {
+        req_count = 2;
+        phy_addr &= ~1;
+    } else
+        req_count = 1;
+
+    switch (cmd) {
+    case LOAD_WORD:
+        load_word(ch, key, phy_addr, req_count);
+        return;
+
+    case STORE_WORD:
+        store_word(ch, key, phy_addr, req_count);
+        return;
+    }
+}
+
+static void DBDMA_run(DBDMAState *s)
+{
+    int channel;
+
+    for (channel = 0; channel < DBDMA_CHANNELS; channel++) {
+        DBDMA_channel *ch = &s->channels[channel];
+        uint32_t status = ch->regs[DBDMA_STATUS];
+        if (!ch->io.processing && (status & RUN) && (status & ACTIVE)) {
+            channel_run(ch);
+        }
+    }
+}
+
+static void DBDMA_run_bh(void *opaque)
+{
+    DBDMAState *s = opaque;
+
+    DBDMA_DPRINTF("DBDMA_run_bh\n");
+
+    DBDMA_run(s);
+}
+
+void DBDMA_kick(DBDMAState *dbdma)
+{
+    qemu_bh_schedule(dbdma->bh);
+}
+
+void DBDMA_register_channel(void *dbdma, int nchan, qemu_irq irq,
+                            DBDMA_rw rw, DBDMA_flush flush,
+                            void *opaque)
+{
+    DBDMAState *s = dbdma;
+    DBDMA_channel *ch = &s->channels[nchan];
+
+    DBDMA_DPRINTF("DBDMA_register_channel 0x%x\n", nchan);
+
+    ch->irq = irq;
+    ch->channel = nchan;
+    ch->rw = rw;
+    ch->flush = flush;
+    ch->io.opaque = opaque;
+    ch->io.channel = ch;
+}
+
+static void
+dbdma_control_write(DBDMA_channel *ch)
+{
+    uint16_t mask, value;
+    uint32_t status;
+
+    mask = (ch->regs[DBDMA_CONTROL] >> 16) & 0xffff;
+    value = ch->regs[DBDMA_CONTROL] & 0xffff;
+
+    value &= (RUN | PAUSE | FLUSH | WAKE | DEVSTAT);
+
+    status = ch->regs[DBDMA_STATUS];
+
+    status = (value & mask) | (status & ~mask);
+
+    if (status & WAKE)
+        status |= ACTIVE;
+    if (status & RUN) {
+        status |= ACTIVE;
+        status &= ~DEAD;
+    }
+    if (status & PAUSE)
+        status &= ~ACTIVE;
+    if ((ch->regs[DBDMA_STATUS] & RUN) && !(status & RUN)) {
+        /* RUN is cleared */
+        status &= ~(ACTIVE|DEAD);
+        if ((status & FLUSH) && ch->flush) {
+            ch->flush(&ch->io);
+            status &= ~FLUSH;
+        }
+    }
+
+    DBDMA_DPRINTF("    status 0x%08x\n", status);
+
+    ch->regs[DBDMA_STATUS] = status;
+
+    if (status & ACTIVE) {
+        DBDMA_kick(dbdma_from_ch(ch));
+    }
+    if ((status & FLUSH) && ch->flush) {
+        ch->flush(&ch->io);
+    }
+}
+
+static void dbdma_write(void *opaque, hwaddr addr,
+                        uint64_t value, unsigned size)
+{
+    int channel = addr >> DBDMA_CHANNEL_SHIFT;
+    DBDMAState *s = opaque;
+    DBDMA_channel *ch = &s->channels[channel];
+    int reg = (addr - (channel << DBDMA_CHANNEL_SHIFT)) >> 2;
+
+    DBDMA_DPRINTF("writel 0x" TARGET_FMT_plx " <= 0x%08"PRIx64"\n",
+                  addr, value);
+    DBDMA_DPRINTF("channel 0x%x reg 0x%x\n",
+                  (uint32_t)addr >> DBDMA_CHANNEL_SHIFT, reg);
+
+    /* cmdptr cannot be modified if channel is ACTIVE */
+
+    if (reg == DBDMA_CMDPTR_LO && (ch->regs[DBDMA_STATUS] & ACTIVE)) {
+        return;
+    }
+
+    ch->regs[reg] = value;
+
+    switch(reg) {
+    case DBDMA_CONTROL:
+        dbdma_control_write(ch);
+        break;
+    case DBDMA_CMDPTR_LO:
+        /* 16-byte aligned */
+        ch->regs[DBDMA_CMDPTR_LO] &= ~0xf;
+        dbdma_cmdptr_load(ch);
+        break;
+    case DBDMA_STATUS:
+    case DBDMA_INTR_SEL:
+    case DBDMA_BRANCH_SEL:
+    case DBDMA_WAIT_SEL:
+        /* nothing to do */
+        break;
+    case DBDMA_XFER_MODE:
+    case DBDMA_CMDPTR_HI:
+    case DBDMA_DATA2PTR_HI:
+    case DBDMA_DATA2PTR_LO:
+    case DBDMA_ADDRESS_HI:
+    case DBDMA_BRANCH_ADDR_HI:
+    case DBDMA_RES1:
+    case DBDMA_RES2:
+    case DBDMA_RES3:
+    case DBDMA_RES4:
+        /* unused */
+        break;
+    }
+}
+
+static uint64_t dbdma_read(void *opaque, hwaddr addr,
+                           unsigned size)
+{
+    uint32_t value;
+    int channel = addr >> DBDMA_CHANNEL_SHIFT;
+    DBDMAState *s = opaque;
+    DBDMA_channel *ch = &s->channels[channel];
+    int reg = (addr - (channel << DBDMA_CHANNEL_SHIFT)) >> 2;
+
+    value = ch->regs[reg];
+
+    DBDMA_DPRINTF("readl 0x" TARGET_FMT_plx " => 0x%08x\n", addr, value);
+    DBDMA_DPRINTF("channel 0x%x reg 0x%x\n",
+                  (uint32_t)addr >> DBDMA_CHANNEL_SHIFT, reg);
+
+    switch(reg) {
+    case DBDMA_CONTROL:
+        value = 0;
+        break;
+    case DBDMA_STATUS:
+    case DBDMA_CMDPTR_LO:
+    case DBDMA_INTR_SEL:
+    case DBDMA_BRANCH_SEL:
+    case DBDMA_WAIT_SEL:
+        /* nothing to do */
+        break;
+    case DBDMA_XFER_MODE:
+    case DBDMA_CMDPTR_HI:
+    case DBDMA_DATA2PTR_HI:
+    case DBDMA_DATA2PTR_LO:
+    case DBDMA_ADDRESS_HI:
+    case DBDMA_BRANCH_ADDR_HI:
+        /* unused */
+        value = 0;
+        break;
+    case DBDMA_RES1:
+    case DBDMA_RES2:
+    case DBDMA_RES3:
+    case DBDMA_RES4:
+        /* reserved */
+        break;
+    }
+
+    return value;
+}
+
+static const MemoryRegionOps dbdma_ops = {
+    .read = dbdma_read,
+    .write = dbdma_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+};
+
+static const VMStateDescription vmstate_dbdma_channel = {
+    .name = "dbdma_channel",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, struct DBDMA_channel, DBDMA_REGS),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_dbdma = {
+    .name = "dbdma",
+    .version_id = 2,
+    .minimum_version_id = 2,
+    .fields = (VMStateField[]) {
+        VMSTATE_STRUCT_ARRAY(channels, DBDMAState, DBDMA_CHANNELS, 1,
+                             vmstate_dbdma_channel, DBDMA_channel),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void dbdma_reset(void *opaque)
+{
+    DBDMAState *s = opaque;
+    int i;
+
+    for (i = 0; i < DBDMA_CHANNELS; i++)
+        memset(s->channels[i].regs, 0, DBDMA_SIZE);
+}
+
+void* DBDMA_init (MemoryRegion **dbdma_mem)
+{
+    DBDMAState *s;
+    int i;
+
+    s = g_malloc0(sizeof(DBDMAState));
+
+    for (i = 0; i < DBDMA_CHANNELS; i++) {
+        DBDMA_io *io = &s->channels[i].io;
+        qemu_iovec_init(&io->iov, 1);
+    }
+
+    memory_region_init_io(&s->mem, NULL, &dbdma_ops, s, "dbdma", 0x1000);
+    *dbdma_mem = &s->mem;
+    vmstate_register(NULL, -1, &vmstate_dbdma, s);
+    qemu_register_reset(dbdma_reset, s);
+
+    s->bh = qemu_bh_new(DBDMA_run_bh, s);
+
+    return s;
+}