xlnx-zdma: Add a model of the Xilinx ZynqMP generic DMA

Add a model of the generic DMA found on Xilinx ZynqMP.

Signed-off-by: Francisco Iglesias <frasse.iglesias@gmail.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20180503214201.29082-2-frasse.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 832 insertions, 0 deletions

diff --git a/hw/dma/xlnx-zdma.c b/hw/dma/xlnx-zdma.c
new file mode 100644
index 0000000000..14d86c254b
--- /dev/null
+++ b/hw/dma/xlnx-zdma.c
@@ -0,0 +1,832 @@
+/*
+ * QEMU model of the ZynqMP generic DMA
+ *
+ * Copyright (c) 2014 Xilinx Inc.
+ * Copyright (c) 2018 FEIMTECH AB
+ *
+ * Written by Edgar E. Iglesias <edgar.iglesias@xilinx.com>,
+ *            Francisco Iglesias <francisco.iglesias@feimtech.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 "qemu/osdep.h"
+#include "hw/dma/xlnx-zdma.h"
+#include "qemu/bitops.h"
+#include "qemu/log.h"
+#include "qapi/error.h"
+
+#ifndef XLNX_ZDMA_ERR_DEBUG
+#define XLNX_ZDMA_ERR_DEBUG 0
+#endif
+
+REG32(ZDMA_ERR_CTRL, 0x0)
+    FIELD(ZDMA_ERR_CTRL, APB_ERR_RES, 0, 1)
+REG32(ZDMA_CH_ISR, 0x100)
+    FIELD(ZDMA_CH_ISR, DMA_PAUSE, 11, 1)
+    FIELD(ZDMA_CH_ISR, DMA_DONE, 10, 1)
+    FIELD(ZDMA_CH_ISR, AXI_WR_DATA, 9, 1)
+    FIELD(ZDMA_CH_ISR, AXI_RD_DATA, 8, 1)
+    FIELD(ZDMA_CH_ISR, AXI_RD_DST_DSCR, 7, 1)
+    FIELD(ZDMA_CH_ISR, AXI_RD_SRC_DSCR, 6, 1)
+    FIELD(ZDMA_CH_ISR, IRQ_DST_ACCT_ERR, 5, 1)
+    FIELD(ZDMA_CH_ISR, IRQ_SRC_ACCT_ERR, 4, 1)
+    FIELD(ZDMA_CH_ISR, BYTE_CNT_OVRFL, 3, 1)
+    FIELD(ZDMA_CH_ISR, DST_DSCR_DONE, 2, 1)
+    FIELD(ZDMA_CH_ISR, SRC_DSCR_DONE, 1, 1)
+    FIELD(ZDMA_CH_ISR, INV_APB, 0, 1)
+REG32(ZDMA_CH_IMR, 0x104)
+    FIELD(ZDMA_CH_IMR, DMA_PAUSE, 11, 1)
+    FIELD(ZDMA_CH_IMR, DMA_DONE, 10, 1)
+    FIELD(ZDMA_CH_IMR, AXI_WR_DATA, 9, 1)
+    FIELD(ZDMA_CH_IMR, AXI_RD_DATA, 8, 1)
+    FIELD(ZDMA_CH_IMR, AXI_RD_DST_DSCR, 7, 1)
+    FIELD(ZDMA_CH_IMR, AXI_RD_SRC_DSCR, 6, 1)
+    FIELD(ZDMA_CH_IMR, IRQ_DST_ACCT_ERR, 5, 1)
+    FIELD(ZDMA_CH_IMR, IRQ_SRC_ACCT_ERR, 4, 1)
+    FIELD(ZDMA_CH_IMR, BYTE_CNT_OVRFL, 3, 1)
+    FIELD(ZDMA_CH_IMR, DST_DSCR_DONE, 2, 1)
+    FIELD(ZDMA_CH_IMR, SRC_DSCR_DONE, 1, 1)
+    FIELD(ZDMA_CH_IMR, INV_APB, 0, 1)
+REG32(ZDMA_CH_IEN, 0x108)
+    FIELD(ZDMA_CH_IEN, DMA_PAUSE, 11, 1)
+    FIELD(ZDMA_CH_IEN, DMA_DONE, 10, 1)
+    FIELD(ZDMA_CH_IEN, AXI_WR_DATA, 9, 1)
+    FIELD(ZDMA_CH_IEN, AXI_RD_DATA, 8, 1)
+    FIELD(ZDMA_CH_IEN, AXI_RD_DST_DSCR, 7, 1)
+    FIELD(ZDMA_CH_IEN, AXI_RD_SRC_DSCR, 6, 1)
+    FIELD(ZDMA_CH_IEN, IRQ_DST_ACCT_ERR, 5, 1)
+    FIELD(ZDMA_CH_IEN, IRQ_SRC_ACCT_ERR, 4, 1)
+    FIELD(ZDMA_CH_IEN, BYTE_CNT_OVRFL, 3, 1)
+    FIELD(ZDMA_CH_IEN, DST_DSCR_DONE, 2, 1)
+    FIELD(ZDMA_CH_IEN, SRC_DSCR_DONE, 1, 1)
+    FIELD(ZDMA_CH_IEN, INV_APB, 0, 1)
+REG32(ZDMA_CH_IDS, 0x10c)
+    FIELD(ZDMA_CH_IDS, DMA_PAUSE, 11, 1)
+    FIELD(ZDMA_CH_IDS, DMA_DONE, 10, 1)
+    FIELD(ZDMA_CH_IDS, AXI_WR_DATA, 9, 1)
+    FIELD(ZDMA_CH_IDS, AXI_RD_DATA, 8, 1)
+    FIELD(ZDMA_CH_IDS, AXI_RD_DST_DSCR, 7, 1)
+    FIELD(ZDMA_CH_IDS, AXI_RD_SRC_DSCR, 6, 1)
+    FIELD(ZDMA_CH_IDS, IRQ_DST_ACCT_ERR, 5, 1)
+    FIELD(ZDMA_CH_IDS, IRQ_SRC_ACCT_ERR, 4, 1)
+    FIELD(ZDMA_CH_IDS, BYTE_CNT_OVRFL, 3, 1)
+    FIELD(ZDMA_CH_IDS, DST_DSCR_DONE, 2, 1)
+    FIELD(ZDMA_CH_IDS, SRC_DSCR_DONE, 1, 1)
+    FIELD(ZDMA_CH_IDS, INV_APB, 0, 1)
+REG32(ZDMA_CH_CTRL0, 0x110)
+    FIELD(ZDMA_CH_CTRL0, OVR_FETCH, 7, 1)
+    FIELD(ZDMA_CH_CTRL0, POINT_TYPE, 6, 1)
+    FIELD(ZDMA_CH_CTRL0, MODE, 4, 2)
+    FIELD(ZDMA_CH_CTRL0, RATE_CTRL, 3, 1)
+    FIELD(ZDMA_CH_CTRL0, CONT_ADDR, 2, 1)
+    FIELD(ZDMA_CH_CTRL0, CONT, 1, 1)
+REG32(ZDMA_CH_CTRL1, 0x114)
+    FIELD(ZDMA_CH_CTRL1, DST_ISSUE, 5, 5)
+    FIELD(ZDMA_CH_CTRL1, SRC_ISSUE, 0, 5)
+REG32(ZDMA_CH_FCI, 0x118)
+    FIELD(ZDMA_CH_FCI, PROG_CELL_CNT, 2, 2)
+    FIELD(ZDMA_CH_FCI, SIDE, 1, 1)
+    FIELD(ZDMA_CH_FCI, EN, 0, 1)
+REG32(ZDMA_CH_STATUS, 0x11c)
+    FIELD(ZDMA_CH_STATUS, STATE, 0, 2)
+REG32(ZDMA_CH_DATA_ATTR, 0x120)
+    FIELD(ZDMA_CH_DATA_ATTR, ARBURST, 26, 2)
+    FIELD(ZDMA_CH_DATA_ATTR, ARCACHE, 22, 4)
+    FIELD(ZDMA_CH_DATA_ATTR, ARQOS, 18, 4)
+    FIELD(ZDMA_CH_DATA_ATTR, ARLEN, 14, 4)
+    FIELD(ZDMA_CH_DATA_ATTR, AWBURST, 12, 2)
+    FIELD(ZDMA_CH_DATA_ATTR, AWCACHE, 8, 4)
+    FIELD(ZDMA_CH_DATA_ATTR, AWQOS, 4, 4)
+    FIELD(ZDMA_CH_DATA_ATTR, AWLEN, 0, 4)
+REG32(ZDMA_CH_DSCR_ATTR, 0x124)
+    FIELD(ZDMA_CH_DSCR_ATTR, AXCOHRNT, 8, 1)
+    FIELD(ZDMA_CH_DSCR_ATTR, AXCACHE, 4, 4)
+    FIELD(ZDMA_CH_DSCR_ATTR, AXQOS, 0, 4)
+REG32(ZDMA_CH_SRC_DSCR_WORD0, 0x128)
+REG32(ZDMA_CH_SRC_DSCR_WORD1, 0x12c)
+    FIELD(ZDMA_CH_SRC_DSCR_WORD1, MSB, 0, 17)
+REG32(ZDMA_CH_SRC_DSCR_WORD2, 0x130)
+    FIELD(ZDMA_CH_SRC_DSCR_WORD2, SIZE, 0, 30)
+REG32(ZDMA_CH_SRC_DSCR_WORD3, 0x134)
+    FIELD(ZDMA_CH_SRC_DSCR_WORD3, CMD, 3, 2)
+    FIELD(ZDMA_CH_SRC_DSCR_WORD3, INTR, 2, 1)
+    FIELD(ZDMA_CH_SRC_DSCR_WORD3, TYPE, 1, 1)
+    FIELD(ZDMA_CH_SRC_DSCR_WORD3, COHRNT, 0, 1)
+REG32(ZDMA_CH_DST_DSCR_WORD0, 0x138)
+REG32(ZDMA_CH_DST_DSCR_WORD1, 0x13c)
+    FIELD(ZDMA_CH_DST_DSCR_WORD1, MSB, 0, 17)
+REG32(ZDMA_CH_DST_DSCR_WORD2, 0x140)
+    FIELD(ZDMA_CH_DST_DSCR_WORD2, SIZE, 0, 30)
+REG32(ZDMA_CH_DST_DSCR_WORD3, 0x144)
+    FIELD(ZDMA_CH_DST_DSCR_WORD3, INTR, 2, 1)
+    FIELD(ZDMA_CH_DST_DSCR_WORD3, TYPE, 1, 1)
+    FIELD(ZDMA_CH_DST_DSCR_WORD3, COHRNT, 0, 1)
+REG32(ZDMA_CH_WR_ONLY_WORD0, 0x148)
+REG32(ZDMA_CH_WR_ONLY_WORD1, 0x14c)
+REG32(ZDMA_CH_WR_ONLY_WORD2, 0x150)
+REG32(ZDMA_CH_WR_ONLY_WORD3, 0x154)
+REG32(ZDMA_CH_SRC_START_LSB, 0x158)
+REG32(ZDMA_CH_SRC_START_MSB, 0x15c)
+    FIELD(ZDMA_CH_SRC_START_MSB, ADDR, 0, 17)
+REG32(ZDMA_CH_DST_START_LSB, 0x160)
+REG32(ZDMA_CH_DST_START_MSB, 0x164)
+    FIELD(ZDMA_CH_DST_START_MSB, ADDR, 0, 17)
+REG32(ZDMA_CH_RATE_CTRL, 0x18c)
+    FIELD(ZDMA_CH_RATE_CTRL, CNT, 0, 12)
+REG32(ZDMA_CH_SRC_CUR_PYLD_LSB, 0x168)
+REG32(ZDMA_CH_SRC_CUR_PYLD_MSB, 0x16c)
+    FIELD(ZDMA_CH_SRC_CUR_PYLD_MSB, ADDR, 0, 17)
+REG32(ZDMA_CH_DST_CUR_PYLD_LSB, 0x170)
+REG32(ZDMA_CH_DST_CUR_PYLD_MSB, 0x174)
+    FIELD(ZDMA_CH_DST_CUR_PYLD_MSB, ADDR, 0, 17)
+REG32(ZDMA_CH_SRC_CUR_DSCR_LSB, 0x178)
+REG32(ZDMA_CH_SRC_CUR_DSCR_MSB, 0x17c)
+    FIELD(ZDMA_CH_SRC_CUR_DSCR_MSB, ADDR, 0, 17)
+REG32(ZDMA_CH_DST_CUR_DSCR_LSB, 0x180)
+REG32(ZDMA_CH_DST_CUR_DSCR_MSB, 0x184)
+    FIELD(ZDMA_CH_DST_CUR_DSCR_MSB, ADDR, 0, 17)
+REG32(ZDMA_CH_TOTAL_BYTE, 0x188)
+REG32(ZDMA_CH_RATE_CNTL, 0x18c)
+    FIELD(ZDMA_CH_RATE_CNTL, CNT, 0, 12)
+REG32(ZDMA_CH_IRQ_SRC_ACCT, 0x190)
+    FIELD(ZDMA_CH_IRQ_SRC_ACCT, CNT, 0, 8)
+REG32(ZDMA_CH_IRQ_DST_ACCT, 0x194)
+    FIELD(ZDMA_CH_IRQ_DST_ACCT, CNT, 0, 8)
+REG32(ZDMA_CH_DBG0, 0x198)
+    FIELD(ZDMA_CH_DBG0, CMN_BUF_FREE, 0, 9)
+REG32(ZDMA_CH_DBG1, 0x19c)
+    FIELD(ZDMA_CH_DBG1, CMN_BUF_OCC, 0, 9)
+REG32(ZDMA_CH_CTRL2, 0x200)
+    FIELD(ZDMA_CH_CTRL2, EN, 0, 1)
+
+enum {
+    PT_REG = 0,
+    PT_MEM = 1,
+};
+
+enum {
+    CMD_HALT = 1,
+    CMD_STOP = 2,
+};
+
+enum {
+    RW_MODE_RW = 0,
+    RW_MODE_WO = 1,
+    RW_MODE_RO = 2,
+};
+
+enum {
+    DTYPE_LINEAR = 0,
+    DTYPE_LINKED = 1,
+};
+
+enum {
+    AXI_BURST_FIXED = 0,
+    AXI_BURST_INCR  = 1,
+};
+
+static void zdma_ch_imr_update_irq(XlnxZDMA *s)
+{
+    bool pending;
+
+    pending = s->regs[R_ZDMA_CH_ISR] & ~s->regs[R_ZDMA_CH_IMR];
+
+    qemu_set_irq(s->irq_zdma_ch_imr, pending);
+}
+
+static void zdma_ch_isr_postw(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxZDMA *s = XLNX_ZDMA(reg->opaque);
+    zdma_ch_imr_update_irq(s);
+}
+
+static uint64_t zdma_ch_ien_prew(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxZDMA *s = XLNX_ZDMA(reg->opaque);
+    uint32_t val = val64;
+
+    s->regs[R_ZDMA_CH_IMR] &= ~val;
+    zdma_ch_imr_update_irq(s);
+    return 0;
+}
+
+static uint64_t zdma_ch_ids_prew(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxZDMA *s = XLNX_ZDMA(reg->opaque);
+    uint32_t val = val64;
+
+    s->regs[R_ZDMA_CH_IMR] |= val;
+    zdma_ch_imr_update_irq(s);
+    return 0;
+}
+
+static void zdma_set_state(XlnxZDMA *s, XlnxZDMAState state)
+{
+    s->state = state;
+    ARRAY_FIELD_DP32(s->regs, ZDMA_CH_STATUS, STATE, state);
+
+    /* Signal error if we have an error condition.  */
+    if (s->error) {
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_STATUS, STATE, 3);
+    }
+}
+
+static void zdma_src_done(XlnxZDMA *s)
+{
+    unsigned int cnt;
+    cnt = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_IRQ_SRC_ACCT, CNT);
+    cnt++;
+    ARRAY_FIELD_DP32(s->regs, ZDMA_CH_IRQ_SRC_ACCT, CNT, cnt);
+    ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, SRC_DSCR_DONE, true);
+
+    /* Did we overflow?  */
+    if (cnt != ARRAY_FIELD_EX32(s->regs, ZDMA_CH_IRQ_SRC_ACCT, CNT)) {
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, IRQ_SRC_ACCT_ERR, true);
+    }
+    zdma_ch_imr_update_irq(s);
+}
+
+static void zdma_dst_done(XlnxZDMA *s)
+{
+    unsigned int cnt;
+    cnt = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_IRQ_DST_ACCT, CNT);
+    cnt++;
+    ARRAY_FIELD_DP32(s->regs, ZDMA_CH_IRQ_DST_ACCT, CNT, cnt);
+    ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, DST_DSCR_DONE, true);
+
+    /* Did we overflow?  */
+    if (cnt != ARRAY_FIELD_EX32(s->regs, ZDMA_CH_IRQ_DST_ACCT, CNT)) {
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, IRQ_DST_ACCT_ERR, true);
+    }
+    zdma_ch_imr_update_irq(s);
+}
+
+static uint64_t zdma_get_regaddr64(XlnxZDMA *s, unsigned int basereg)
+{
+    uint64_t addr;
+
+    addr = s->regs[basereg + 1];
+    addr <<= 32;
+    addr |= s->regs[basereg];
+
+    return addr;
+}
+
+static void zdma_put_regaddr64(XlnxZDMA *s, unsigned int basereg, uint64_t addr)
+{
+    s->regs[basereg] = addr;
+    s->regs[basereg + 1] = addr >> 32;
+}
+
+static bool zdma_load_descriptor(XlnxZDMA *s, uint64_t addr, void *buf)
+{
+    /* ZDMA descriptors must be aligned to their own size.  */
+    if (addr % sizeof(XlnxZDMADescr)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "zdma: unaligned descriptor at %" PRIx64,
+                      addr);
+        memset(buf, 0xdeadbeef, sizeof(XlnxZDMADescr));
+        s->error = true;
+        return false;
+    }
+
+    address_space_rw(s->dma_as, addr, s->attr,
+                     buf, sizeof(XlnxZDMADescr), false);
+    return true;
+}
+
+static void zdma_load_src_descriptor(XlnxZDMA *s)
+{
+    uint64_t src_addr;
+    unsigned int ptype = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, POINT_TYPE);
+
+    if (ptype == PT_REG) {
+        memcpy(&s->dsc_src, &s->regs[R_ZDMA_CH_SRC_DSCR_WORD0],
+               sizeof(s->dsc_src));
+        return;
+    }
+
+    src_addr = zdma_get_regaddr64(s, R_ZDMA_CH_SRC_CUR_DSCR_LSB);
+
+    if (!zdma_load_descriptor(s, src_addr, &s->dsc_src)) {
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, AXI_RD_SRC_DSCR, true);
+    }
+}
+
+static void zdma_load_dst_descriptor(XlnxZDMA *s)
+{
+    uint64_t dst_addr;
+    unsigned int ptype = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, POINT_TYPE);
+
+    if (ptype == PT_REG) {
+        memcpy(&s->dsc_dst, &s->regs[R_ZDMA_CH_DST_DSCR_WORD0],
+               sizeof(s->dsc_dst));
+        return;
+    }
+
+    dst_addr = zdma_get_regaddr64(s, R_ZDMA_CH_DST_CUR_DSCR_LSB);
+
+    if (!zdma_load_descriptor(s, dst_addr, &s->dsc_dst)) {
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, AXI_RD_DST_DSCR, true);
+    }
+}
+
+static uint64_t zdma_update_descr_addr(XlnxZDMA *s, bool type,
+                                       unsigned int basereg)
+{
+    uint64_t addr, next;
+
+    if (type == DTYPE_LINEAR) {
+        next = zdma_get_regaddr64(s, basereg);
+        next += sizeof(s->dsc_dst);
+        zdma_put_regaddr64(s, basereg, next);
+    } else {
+        addr = zdma_get_regaddr64(s, basereg);
+        addr += sizeof(s->dsc_dst);
+        address_space_rw(s->dma_as, addr, s->attr, (void *) &next, 8, false);
+        zdma_put_regaddr64(s, basereg, next);
+    }
+    return next;
+}
+
+static void zdma_write_dst(XlnxZDMA *s, uint8_t *buf, uint32_t len)
+{
+    uint32_t dst_size, dlen;
+    bool dst_intr, dst_type;
+    unsigned int ptype = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, POINT_TYPE);
+    unsigned int rw_mode = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, MODE);
+    unsigned int burst_type = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_DATA_ATTR,
+                                               AWBURST);
+
+    /* FIXED burst types are only supported in simple dma mode.  */
+    if (ptype != PT_REG) {
+        burst_type = AXI_BURST_INCR;
+    }
+
+    while (len) {
+        dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
+                              SIZE);
+        dst_type = FIELD_EX32(s->dsc_dst.words[3], ZDMA_CH_DST_DSCR_WORD3,
+                              TYPE);
+        if (dst_size == 0 && ptype == PT_MEM) {
+            uint64_t next;
+            next = zdma_update_descr_addr(s, dst_type,
+                                          R_ZDMA_CH_DST_CUR_DSCR_LSB);
+            zdma_load_descriptor(s, next, &s->dsc_dst);
+            dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
+                                  SIZE);
+            dst_type = FIELD_EX32(s->dsc_dst.words[3], ZDMA_CH_DST_DSCR_WORD3,
+                                  TYPE);
+        }
+
+        /* Match what hardware does by ignoring the dst_size and only using
+         * the src size for Simple register mode.  */
+        if (ptype == PT_REG && rw_mode != RW_MODE_WO) {
+            dst_size = len;
+        }
+
+        dst_intr = FIELD_EX32(s->dsc_dst.words[3], ZDMA_CH_DST_DSCR_WORD3,
+                              INTR);
+
+        dlen = len > dst_size ? dst_size : len;
+        if (burst_type == AXI_BURST_FIXED) {
+            if (dlen > (s->cfg.bus_width / 8)) {
+                dlen = s->cfg.bus_width / 8;
+            }
+        }
+
+        address_space_rw(s->dma_as, s->dsc_dst.addr, s->attr, buf, dlen,
+                         true);
+        if (burst_type == AXI_BURST_INCR) {
+            s->dsc_dst.addr += dlen;
+        }
+        dst_size -= dlen;
+        buf += dlen;
+        len -= dlen;
+
+        if (dst_size == 0 && dst_intr) {
+            zdma_dst_done(s);
+        }
+
+        /* Write back to buffered descriptor.  */
+        s->dsc_dst.words[2] = FIELD_DP32(s->dsc_dst.words[2],
+                                         ZDMA_CH_DST_DSCR_WORD2,
+                                         SIZE,
+                                         dst_size);
+    }
+}
+
+static void zdma_process_descr(XlnxZDMA *s)
+{
+    uint64_t src_addr;
+    uint32_t src_size, len;
+    unsigned int src_cmd;
+    bool src_intr, src_type;
+    unsigned int ptype = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, POINT_TYPE);
+    unsigned int rw_mode = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, MODE);
+    unsigned int burst_type = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_DATA_ATTR,
+                                               ARBURST);
+
+    src_addr = s->dsc_src.addr;
+    src_size = FIELD_EX32(s->dsc_src.words[2], ZDMA_CH_SRC_DSCR_WORD2, SIZE);
+    src_cmd = FIELD_EX32(s->dsc_src.words[3], ZDMA_CH_SRC_DSCR_WORD3, CMD);
+    src_type = FIELD_EX32(s->dsc_src.words[3], ZDMA_CH_SRC_DSCR_WORD3, TYPE);
+    src_intr = FIELD_EX32(s->dsc_src.words[3], ZDMA_CH_SRC_DSCR_WORD3, INTR);
+
+    /* FIXED burst types and non-rw modes are only supported in
+     * simple dma mode.
+     */
+    if (ptype != PT_REG) {
+        if (rw_mode != RW_MODE_RW) {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "zDMA: rw-mode=%d but not simple DMA mode.\n",
+                          rw_mode);
+        }
+        if (burst_type != AXI_BURST_INCR) {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "zDMA: burst_type=%d but not simple DMA mode.\n",
+                          burst_type);
+        }
+        burst_type = AXI_BURST_INCR;
+        rw_mode = RW_MODE_RW;
+    }
+
+    if (rw_mode == RW_MODE_WO) {
+        /* In Simple DMA Write-Only, we need to push DST size bytes
+         * regardless of what SRC size is set to.  */
+        src_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
+                              SIZE);
+        memcpy(s->buf, &s->regs[R_ZDMA_CH_WR_ONLY_WORD0], s->cfg.bus_width / 8);
+    }
+
+    while (src_size) {
+        len = src_size > ARRAY_SIZE(s->buf) ? ARRAY_SIZE(s->buf) : src_size;
+        if (burst_type == AXI_BURST_FIXED) {
+            if (len > (s->cfg.bus_width / 8)) {
+                len = s->cfg.bus_width / 8;
+            }
+        }
+
+        if (rw_mode == RW_MODE_WO) {
+            if (len > s->cfg.bus_width / 8) {
+                len = s->cfg.bus_width / 8;
+            }
+        } else {
+            address_space_rw(s->dma_as, src_addr, s->attr, s->buf, len,
+                             false);
+            if (burst_type == AXI_BURST_INCR) {
+                src_addr += len;
+            }
+        }
+
+        if (rw_mode != RW_MODE_RO) {
+            zdma_write_dst(s, s->buf, len);
+        }
+
+        s->regs[R_ZDMA_CH_TOTAL_BYTE] += len;
+        src_size -= len;
+    }
+
+    ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, DMA_DONE, true);
+
+    if (src_intr) {
+        zdma_src_done(s);
+    }
+
+    /* Load next descriptor.  */
+    if (ptype == PT_REG || src_cmd == CMD_STOP) {
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_CTRL2, EN, 0);
+        zdma_set_state(s, DISABLED);
+        return;
+    }
+
+    if (src_cmd == CMD_HALT) {
+        zdma_set_state(s, PAUSED);
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, DMA_PAUSE, 1);
+        zdma_ch_imr_update_irq(s);
+        return;
+    }
+
+    zdma_update_descr_addr(s, src_type, R_ZDMA_CH_SRC_CUR_DSCR_LSB);
+}
+
+static void zdma_run(XlnxZDMA *s)
+{
+    while (s->state == ENABLED && !s->error) {
+        zdma_load_src_descriptor(s);
+
+        if (s->error) {
+            zdma_set_state(s, DISABLED);
+        } else {
+            zdma_process_descr(s);
+        }
+    }
+
+    zdma_ch_imr_update_irq(s);
+}
+
+static void zdma_update_descr_addr_from_start(XlnxZDMA *s)
+{
+    uint64_t src_addr, dst_addr;
+
+    src_addr = zdma_get_regaddr64(s, R_ZDMA_CH_SRC_START_LSB);
+    zdma_put_regaddr64(s, R_ZDMA_CH_SRC_CUR_DSCR_LSB, src_addr);
+    dst_addr = zdma_get_regaddr64(s, R_ZDMA_CH_DST_START_LSB);
+    zdma_put_regaddr64(s, R_ZDMA_CH_DST_CUR_DSCR_LSB, dst_addr);
+    zdma_load_dst_descriptor(s);
+}
+
+static void zdma_ch_ctrlx_postw(RegisterInfo *reg, uint64_t val64)
+{
+    XlnxZDMA *s = XLNX_ZDMA(reg->opaque);
+
+    if (ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL2, EN)) {
+        s->error = false;
+
+        if (s->state == PAUSED &&
+            ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, CONT)) {
+            if (ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, CONT_ADDR) == 1) {
+                zdma_update_descr_addr_from_start(s);
+            } else {
+                bool src_type = FIELD_EX32(s->dsc_src.words[3],
+                                       ZDMA_CH_SRC_DSCR_WORD3, TYPE);
+                zdma_update_descr_addr(s, src_type,
+                                          R_ZDMA_CH_SRC_CUR_DSCR_LSB);
+            }
+            ARRAY_FIELD_DP32(s->regs, ZDMA_CH_CTRL0, CONT, false);
+            zdma_set_state(s, ENABLED);
+        } else if (s->state == DISABLED) {
+            zdma_update_descr_addr_from_start(s);
+            zdma_set_state(s, ENABLED);
+        }
+    } else {
+        /* Leave Paused state?  */
+        if (s->state == PAUSED &&
+            ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, CONT)) {
+            zdma_set_state(s, DISABLED);
+        }
+    }
+
+    zdma_run(s);
+}
+
+static RegisterAccessInfo zdma_regs_info[] = {
+    {   .name = "ZDMA_ERR_CTRL",  .addr = A_ZDMA_ERR_CTRL,
+        .rsvd = 0xfffffffe,
+    },{ .name = "ZDMA_CH_ISR",  .addr = A_ZDMA_CH_ISR,
+        .rsvd = 0xfffff000,
+        .w1c = 0xfff,
+        .post_write = zdma_ch_isr_postw,
+    },{ .name = "ZDMA_CH_IMR",  .addr = A_ZDMA_CH_IMR,
+        .reset = 0xfff,
+        .rsvd = 0xfffff000,
+        .ro = 0xfff,
+    },{ .name = "ZDMA_CH_IEN",  .addr = A_ZDMA_CH_IEN,
+        .rsvd = 0xfffff000,
+        .pre_write = zdma_ch_ien_prew,
+    },{ .name = "ZDMA_CH_IDS",  .addr = A_ZDMA_CH_IDS,
+        .rsvd = 0xfffff000,
+        .pre_write = zdma_ch_ids_prew,
+    },{ .name = "ZDMA_CH_CTRL0",  .addr = A_ZDMA_CH_CTRL0,
+        .reset = 0x80,
+        .rsvd = 0xffffff01,
+        .post_write = zdma_ch_ctrlx_postw,
+    },{ .name = "ZDMA_CH_CTRL1",  .addr = A_ZDMA_CH_CTRL1,
+        .reset = 0x3ff,
+        .rsvd = 0xfffffc00,
+    },{ .name = "ZDMA_CH_FCI",  .addr = A_ZDMA_CH_FCI,
+        .rsvd = 0xffffffc0,
+    },{ .name = "ZDMA_CH_STATUS",  .addr = A_ZDMA_CH_STATUS,
+        .rsvd = 0xfffffffc,
+        .ro = 0x3,
+    },{ .name = "ZDMA_CH_DATA_ATTR",  .addr = A_ZDMA_CH_DATA_ATTR,
+        .reset = 0x483d20f,
+        .rsvd = 0xf0000000,
+    },{ .name = "ZDMA_CH_DSCR_ATTR",  .addr = A_ZDMA_CH_DSCR_ATTR,
+        .rsvd = 0xfffffe00,
+    },{ .name = "ZDMA_CH_SRC_DSCR_WORD0",  .addr = A_ZDMA_CH_SRC_DSCR_WORD0,
+    },{ .name = "ZDMA_CH_SRC_DSCR_WORD1",  .addr = A_ZDMA_CH_SRC_DSCR_WORD1,
+        .rsvd = 0xfffe0000,
+    },{ .name = "ZDMA_CH_SRC_DSCR_WORD2",  .addr = A_ZDMA_CH_SRC_DSCR_WORD2,
+        .rsvd = 0xc0000000,
+    },{ .name = "ZDMA_CH_SRC_DSCR_WORD3",  .addr = A_ZDMA_CH_SRC_DSCR_WORD3,
+        .rsvd = 0xffffffe0,
+    },{ .name = "ZDMA_CH_DST_DSCR_WORD0",  .addr = A_ZDMA_CH_DST_DSCR_WORD0,
+    },{ .name = "ZDMA_CH_DST_DSCR_WORD1",  .addr = A_ZDMA_CH_DST_DSCR_WORD1,
+        .rsvd = 0xfffe0000,
+    },{ .name = "ZDMA_CH_DST_DSCR_WORD2",  .addr = A_ZDMA_CH_DST_DSCR_WORD2,
+        .rsvd = 0xc0000000,
+    },{ .name = "ZDMA_CH_DST_DSCR_WORD3",  .addr = A_ZDMA_CH_DST_DSCR_WORD3,
+        .rsvd = 0xfffffffa,
+    },{ .name = "ZDMA_CH_WR_ONLY_WORD0",  .addr = A_ZDMA_CH_WR_ONLY_WORD0,
+    },{ .name = "ZDMA_CH_WR_ONLY_WORD1",  .addr = A_ZDMA_CH_WR_ONLY_WORD1,
+    },{ .name = "ZDMA_CH_WR_ONLY_WORD2",  .addr = A_ZDMA_CH_WR_ONLY_WORD2,
+    },{ .name = "ZDMA_CH_WR_ONLY_WORD3",  .addr = A_ZDMA_CH_WR_ONLY_WORD3,
+    },{ .name = "ZDMA_CH_SRC_START_LSB",  .addr = A_ZDMA_CH_SRC_START_LSB,
+    },{ .name = "ZDMA_CH_SRC_START_MSB",  .addr = A_ZDMA_CH_SRC_START_MSB,
+        .rsvd = 0xfffe0000,
+    },{ .name = "ZDMA_CH_DST_START_LSB",  .addr = A_ZDMA_CH_DST_START_LSB,
+    },{ .name = "ZDMA_CH_DST_START_MSB",  .addr = A_ZDMA_CH_DST_START_MSB,
+        .rsvd = 0xfffe0000,
+    },{ .name = "ZDMA_CH_SRC_CUR_PYLD_LSB",  .addr = A_ZDMA_CH_SRC_CUR_PYLD_LSB,
+        .ro = 0xffffffff,
+    },{ .name = "ZDMA_CH_SRC_CUR_PYLD_MSB",  .addr = A_ZDMA_CH_SRC_CUR_PYLD_MSB,
+        .rsvd = 0xfffe0000,
+        .ro = 0x1ffff,
+    },{ .name = "ZDMA_CH_DST_CUR_PYLD_LSB",  .addr = A_ZDMA_CH_DST_CUR_PYLD_LSB,
+        .ro = 0xffffffff,
+    },{ .name = "ZDMA_CH_DST_CUR_PYLD_MSB",  .addr = A_ZDMA_CH_DST_CUR_PYLD_MSB,
+        .rsvd = 0xfffe0000,
+        .ro = 0x1ffff,
+    },{ .name = "ZDMA_CH_SRC_CUR_DSCR_LSB",  .addr = A_ZDMA_CH_SRC_CUR_DSCR_LSB,
+        .ro = 0xffffffff,
+    },{ .name = "ZDMA_CH_SRC_CUR_DSCR_MSB",  .addr = A_ZDMA_CH_SRC_CUR_DSCR_MSB,
+        .rsvd = 0xfffe0000,
+        .ro = 0x1ffff,
+    },{ .name = "ZDMA_CH_DST_CUR_DSCR_LSB",  .addr = A_ZDMA_CH_DST_CUR_DSCR_LSB,
+        .ro = 0xffffffff,
+    },{ .name = "ZDMA_CH_DST_CUR_DSCR_MSB",  .addr = A_ZDMA_CH_DST_CUR_DSCR_MSB,
+        .rsvd = 0xfffe0000,
+        .ro = 0x1ffff,
+    },{ .name = "ZDMA_CH_TOTAL_BYTE",  .addr = A_ZDMA_CH_TOTAL_BYTE,
+        .w1c = 0xffffffff,
+    },{ .name = "ZDMA_CH_RATE_CNTL",  .addr = A_ZDMA_CH_RATE_CNTL,
+        .rsvd = 0xfffff000,
+    },{ .name = "ZDMA_CH_IRQ_SRC_ACCT",  .addr = A_ZDMA_CH_IRQ_SRC_ACCT,
+        .rsvd = 0xffffff00,
+        .ro = 0xff,
+        .cor = 0xff,
+    },{ .name = "ZDMA_CH_IRQ_DST_ACCT",  .addr = A_ZDMA_CH_IRQ_DST_ACCT,
+        .rsvd = 0xffffff00,
+        .ro = 0xff,
+        .cor = 0xff,
+    },{ .name = "ZDMA_CH_DBG0",  .addr = A_ZDMA_CH_DBG0,
+        .rsvd = 0xfffffe00,
+        .ro = 0x1ff,
+    },{ .name = "ZDMA_CH_DBG1",  .addr = A_ZDMA_CH_DBG1,
+        .rsvd = 0xfffffe00,
+        .ro = 0x1ff,
+    },{ .name = "ZDMA_CH_CTRL2",  .addr = A_ZDMA_CH_CTRL2,
+        .rsvd = 0xfffffffe,
+        .post_write = zdma_ch_ctrlx_postw,
+    }
+};
+
+static void zdma_reset(DeviceState *dev)
+{
+    XlnxZDMA *s = XLNX_ZDMA(dev);
+    unsigned int i;
+
+    for (i = 0; i < ARRAY_SIZE(s->regs_info); ++i) {
+        register_reset(&s->regs_info[i]);
+    }
+
+    zdma_ch_imr_update_irq(s);
+}
+
+static uint64_t zdma_read(void *opaque, hwaddr addr, unsigned size)
+{
+    XlnxZDMA *s = XLNX_ZDMA(opaque);
+    RegisterInfo *r = &s->regs_info[addr / 4];
+
+    if (!r->data) {
+        qemu_log("%s: Decode error: read from %" HWADDR_PRIx "\n",
+                 object_get_canonical_path(OBJECT(s)),
+                 addr);
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, INV_APB, true);
+        zdma_ch_imr_update_irq(s);
+        return 0;
+    }
+    return register_read(r, ~0, NULL, false);
+}
+
+static void zdma_write(void *opaque, hwaddr addr, uint64_t value,
+                      unsigned size)
+{
+    XlnxZDMA *s = XLNX_ZDMA(opaque);
+    RegisterInfo *r = &s->regs_info[addr / 4];
+
+    if (!r->data) {
+        qemu_log("%s: Decode error: write to %" HWADDR_PRIx "=%" PRIx64 "\n",
+                 object_get_canonical_path(OBJECT(s)),
+                 addr, value);
+        ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, INV_APB, true);
+        zdma_ch_imr_update_irq(s);
+        return;
+    }
+    register_write(r, value, ~0, NULL, false);
+}
+
+static const MemoryRegionOps zdma_ops = {
+    .read = zdma_read,
+    .write = zdma_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+};
+
+static void zdma_realize(DeviceState *dev, Error **errp)
+{
+    XlnxZDMA *s = XLNX_ZDMA(dev);
+    unsigned int i;
+
+    for (i = 0; i < ARRAY_SIZE(zdma_regs_info); ++i) {
+        RegisterInfo *r = &s->regs_info[zdma_regs_info[i].addr / 4];
+
+        *r = (RegisterInfo) {
+            .data = (uint8_t *)&s->regs[
+                    zdma_regs_info[i].addr / 4],
+            .data_size = sizeof(uint32_t),
+            .access = &zdma_regs_info[i],
+            .opaque = s,
+        };
+    }
+
+    if (s->dma_mr) {
+        s->dma_as = g_malloc0(sizeof(AddressSpace));
+        address_space_init(s->dma_as, s->dma_mr, NULL);
+    } else {
+        s->dma_as = &address_space_memory;
+    }
+    s->attr = MEMTXATTRS_UNSPECIFIED;
+}
+
+static void zdma_init(Object *obj)
+{
+    XlnxZDMA *s = XLNX_ZDMA(obj);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+
+    memory_region_init_io(&s->iomem, obj, &zdma_ops, s,
+                          TYPE_XLNX_ZDMA, ZDMA_R_MAX * 4);
+    sysbus_init_mmio(sbd, &s->iomem);
+    sysbus_init_irq(sbd, &s->irq_zdma_ch_imr);
+
+    object_property_add_link(obj, "dma", TYPE_MEMORY_REGION,
+                             (Object **)&s->dma_mr,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                             &error_abort);
+}
+
+static const VMStateDescription vmstate_zdma = {
+    .name = TYPE_XLNX_ZDMA,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, XlnxZDMA, ZDMA_R_MAX),
+        VMSTATE_UINT32(state, XlnxZDMA),
+        VMSTATE_UINT32_ARRAY(dsc_src.words, XlnxZDMA, 4),
+        VMSTATE_UINT32_ARRAY(dsc_dst.words, XlnxZDMA, 4),
+        VMSTATE_END_OF_LIST(),
+    }
+};
+
+static Property zdma_props[] = {
+    DEFINE_PROP_UINT32("bus-width", XlnxZDMA, cfg.bus_width, 64),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void zdma_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = zdma_reset;
+    dc->realize = zdma_realize;
+    dc->props = zdma_props;
+    dc->vmsd = &vmstate_zdma;
+}
+
+static const TypeInfo zdma_info = {
+    .name          = TYPE_XLNX_ZDMA,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(XlnxZDMA),
+    .class_init    = zdma_class_init,
+    .instance_init = zdma_init,
+};
+
+static void zdma_register_types(void)
+{
+    type_register_static(&zdma_info);
+}
+
+type_init(zdma_register_types)