[PATCH v2 3/4] hw/dma/xlnx_csu_dma: Always expect 'dma' link property to be set

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Simplify by always passing a MemoryRegion property to the device.
Doing so we can move the AddressSpace field to the device struct,
removing need for heap allocation.

Update the Xilinx ZynqMP SoC model to pass the default system
memory instead of a NULL value.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 include/hw/dma/xlnx_csu_dma.h |  2 +-
 hw/arm/xlnx-zynqmp.c          |  4 ++++
 hw/dma/xlnx_csu_dma.c         | 21 ++++++++++-----------
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/include/hw/dma/xlnx_csu_dma.h b/include/hw/dma/xlnx_csu_dma.h
index 204d94c6737..9e9dc551e99 100644
--- a/include/hw/dma/xlnx_csu_dma.h
+++ b/include/hw/dma/xlnx_csu_dma.h
@@ -30,7 +30,7 @@ typedef struct XlnxCSUDMA {
     MemoryRegion iomem;
     MemTxAttrs attr;
     MemoryRegion *dma_mr;
-    AddressSpace *dma_as;
+    AddressSpace dma_as;
     qemu_irq irq;
     StreamSink *tx_dev; /* Used as generic StreamSink */
     ptimer_state *src_timer;
diff --git a/hw/arm/xlnx-zynqmp.c b/hw/arm/xlnx-zynqmp.c
index 9724978761b..4344e223f2d 100644
--- a/hw/arm/xlnx-zynqmp.c
+++ b/hw/arm/xlnx-zynqmp.c
@@ -620,6 +620,10 @@ static void xlnx_zynqmp_realize(DeviceState *dev, Error **errp)
                            gic_spi[adma_ch_intr[i]]);
     }
 
+    if (!object_property_set_link(OBJECT(&s->qspi_dma), "dma",
+                                  OBJECT(system_memory), errp)) {
+        return;
+    }
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->qspi_dma), errp)) {
         return;
     }
diff --git a/hw/dma/xlnx_csu_dma.c b/hw/dma/xlnx_csu_dma.c
index 2d19f415ef3..896bb3574dd 100644
--- a/hw/dma/xlnx_csu_dma.c
+++ b/hw/dma/xlnx_csu_dma.c
@@ -201,11 +201,11 @@ static uint32_t xlnx_csu_dma_read(XlnxCSUDMA *s, uint8_t *buf, uint32_t len)
         for (i = 0; i < len && (result == MEMTX_OK); i += s->width) {
             uint32_t mlen = MIN(len - i, s->width);
 
-            result = address_space_rw(s->dma_as, addr, s->attr,
+            result = address_space_rw(&s->dma_as, addr, s->attr,
                                       buf + i, mlen, false);
         }
     } else {
-        result = address_space_rw(s->dma_as, addr, s->attr, buf, len, false);
+        result = address_space_rw(&s->dma_as, addr, s->attr, buf, len, false);
     }
 
     if (result == MEMTX_OK) {
@@ -232,12 +232,12 @@ static uint32_t xlnx_csu_dma_write(XlnxCSUDMA *s, uint8_t *buf, uint32_t len)
         for (i = 0; i < len && (result == MEMTX_OK); i += s->width) {
             uint32_t mlen = MIN(len - i, s->width);
 
-            result = address_space_rw(s->dma_as, addr, s->attr,
+            result = address_space_rw(&s->dma_as, addr, s->attr,
                                       buf, mlen, true);
             buf += mlen;
         }
     } else {
-        result = address_space_rw(s->dma_as, addr, s->attr, buf, len, true);
+        result = address_space_rw(&s->dma_as, addr, s->attr, buf, len, true);
     }
 
     if (result != MEMTX_OK) {
@@ -631,6 +631,12 @@ static void xlnx_csu_dma_realize(DeviceState *dev, Error **errp)
         return;
     }
 
+    if (!s->dma_mr) {
+        error_setg(errp, TYPE_XLNX_CSU_DMA " 'dma' link not set");
+        return;
+    }
+    address_space_init(&s->dma_as, s->dma_mr, "csu-dma");
+
     reg_array =
         register_init_block32(dev, xlnx_csu_dma_regs_info[!!s->is_dst],
                               XLNX_CSU_DMA_R_MAX,
@@ -648,13 +654,6 @@ static void xlnx_csu_dma_realize(DeviceState *dev, Error **errp)
     s->src_timer = ptimer_init(xlnx_csu_dma_src_timeout_hit,
                                s, PTIMER_POLICY_DEFAULT);
 
-    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;
 
     s->r_size_last_word = 0;
-- 
2.31.1