diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c
index ab02515..f93cd8e 100644
--- a/hw/net/cadence_gem.c
+++ b/hw/net/cadence_gem.c
@@ -153,6 +153,9 @@
 #define GEM_RECEIVE_Q1_PTR              (0x00000480 / 4)
 #define GEM_RECEIVE_Q7_PTR              (GEM_RECEIVE_Q1_PTR + 6)
 
+#define GEM_TBQPH                       (0x000004C8 / 4)
+#define GEM_RBQPH                       (0x000004D4 / 4)
+
 #define GEM_INT_Q1_ENABLE               (0x00000600 / 4)
 #define GEM_INT_Q7_ENABLE               (GEM_INT_Q1_ENABLE + 6)
 
@@ -832,18 +835,42 @@ static int get_queue_from_screen(CadenceGEMState *s, uint8_t *rxbuf_ptr,
     return 0;
 }
 
+static hwaddr gem_get_desc_addr(CadenceGEMState *s, bool tx, int q)
+{
+    hwaddr desc_addr = 0;
+
+    if (s->regs[GEM_DMACFG] & GEM_DMACFG_ADDR_64B) {
+        desc_addr = s->regs[tx ? GEM_TBQPH : GEM_RBQPH];
+    }
+    desc_addr <<= 32;
+    desc_addr |= tx ? s->tx_desc_addr[q] : s->rx_desc_addr[q];
+    return desc_addr;
+}
+
+static hwaddr gem_get_tx_desc_addr(CadenceGEMState *s, int q)
+{
+    return gem_get_desc_addr(s, true, q);
+}
+
+static hwaddr gem_get_rx_desc_addr(CadenceGEMState *s, int q)
+{
+    return gem_get_desc_addr(s, false, q);
+}
+
 static void gem_get_rx_desc(CadenceGEMState *s, int q)
 {
-    DB_PRINT("read descriptor 0x%x\n", (unsigned)s->rx_desc_addr[q]);
+    hwaddr desc_addr = gem_get_rx_desc_addr(s, q);
+
+    DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", desc_addr);
+
     /* read current descriptor */
-    address_space_read(s->dma_as, s->rx_desc_addr[q], MEMTXATTRS_UNSPECIFIED,
+    address_space_read(s->dma_as, desc_addr, MEMTXATTRS_UNSPECIFIED,
                        (uint8_t *)s->rx_desc[q],
                        sizeof(uint32_t) * gem_get_desc_len(s, true));
 
     /* Descriptor owned by software ? */
     if (rx_desc_get_ownership(s->rx_desc[q]) == 1) {
-        DB_PRINT("descriptor 0x%x owned by sw.\n",
-                 (unsigned)s->rx_desc_addr[q]);
+        DB_PRINT("descriptor 0x%" HWADDR_PRIx " owned by sw.\n", desc_addr);
         s->regs[GEM_RXSTATUS] |= GEM_RXSTATUS_NOBUF;
         s->regs[GEM_ISR] |= GEM_INT_RXUSED & ~(s->regs[GEM_IMR]);
         /* Handle interrupt consequences */
@@ -947,6 +974,8 @@ static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size)
     q = get_queue_from_screen(s, rxbuf_ptr, rxbufsize);
 
     while (bytes_to_copy) {
+        hwaddr desc_addr;
+
         /* Do nothing if receive is not enabled. */
         if (!gem_can_receive(nc)) {
             assert(!first_desc);
@@ -994,7 +1023,8 @@ static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size)
         }
 
         /* Descriptor write-back.  */
-        address_space_write(s->dma_as, s->rx_desc_addr[q],
+        desc_addr = gem_get_rx_desc_addr(s, q);
+        address_space_write(s->dma_as, desc_addr,
                             MEMTXATTRS_UNSPECIFIED,
                             (uint8_t *)s->rx_desc[q],
                             sizeof(uint32_t) * gem_get_desc_len(s, true));
@@ -1098,7 +1128,7 @@ static void gem_transmit(CadenceGEMState *s)
 
     for (q = s->num_priority_queues - 1; q >= 0; q--) {
         /* read current descriptor */
-        packet_desc_addr = s->tx_desc_addr[q];
+        packet_desc_addr = gem_get_tx_desc_addr(s, q);
 
         DB_PRINT("read descriptor 0x%" HWADDR_PRIx "\n", packet_desc_addr);
         address_space_read(s->dma_as, packet_desc_addr,
@@ -1144,16 +1174,17 @@ static void gem_transmit(CadenceGEMState *s)
             /* Last descriptor for this packet; hand the whole thing off */
             if (tx_desc_get_last(desc)) {
                 uint32_t desc_first[DESC_MAX_NUM_WORDS];
+                hwaddr desc_addr = gem_get_tx_desc_addr(s, q);
 
                 /* Modify the 1st descriptor of this packet to be owned by
                  * the processor.
                  */
-                address_space_read(s->dma_as, s->tx_desc_addr[q],
+                address_space_read(s->dma_as, desc_addr,
                                    MEMTXATTRS_UNSPECIFIED,
                                    (uint8_t *)desc_first,
                                    sizeof(desc_first));
                 tx_desc_set_used(desc_first);
-                address_space_write(s->dma_as, s->tx_desc_addr[q],
+                address_space_write(s->dma_as, desc_addr,
                                   MEMTXATTRS_UNSPECIFIED,
                                   (uint8_t *)desc_first,
                                    sizeof(desc_first));
