[Qemu-devel] [PATCH v2 1/1] xlnx-zynqmp: Add support for high DDR memory regions

[Alistair Francis]

The Xilinx ZynqMP SoC and EP108 board supports three memory regions:
 - A 2GB region starting at 0
 - A 32GB region starting at 32GB
 - A 256GB region starting at 768GB

This patch adds support for the first two memory regions, which is
automatically created based on the size specified by the QEMU memory
command line argument.

On hardware the physical memory region is one continuous region, it is then
mapped into the three different regions by the DDRC. As we don't model the
DDRC this is done at startup by QEMU. The board creates the memory region and
then passes that memory region to the SoC. The SoC then maps the memory
regions.

Signed-off-by: Alistair Francis <address@hidden>
---
V2:
 - Create one continuous memory region and pass it to the SoC

Also, the Xilinx ZynqMP TRM is avaliable at:
http://www.xilinx.com/products/silicon-devices/soc/zynq-ultrascale-mpsoc.html?resultsTablePreSelect=documenttype:User%20Guides#documentation

 hw/arm/xlnx-ep108.c          | 42 +++++++++++++++++++++++-------------------
 hw/arm/xlnx-zynqmp.c         | 31 +++++++++++++++++++++++++++++++
 include/hw/arm/xlnx-zynqmp.h | 12 ++++++++++++
 3 files changed, 66 insertions(+), 19 deletions(-)

diff --git a/hw/arm/xlnx-ep108.c b/hw/arm/xlnx-ep108.c
index 85b978f..a0174d5 100644
--- a/hw/arm/xlnx-ep108.c
+++ b/hw/arm/xlnx-ep108.c
@@ -22,12 +22,9 @@
 
 typedef struct XlnxEP108 {
     XlnxZynqMPState soc;
-    MemoryRegion ddr_ram;
+    MemoryRegion ddr_board_ram;
 } XlnxEP108;
 
-/* Max 2GB RAM */
-#define EP108_MAX_RAM_SIZE 0x80000000ull
-
 static struct arm_boot_info xlnx_ep108_binfo;
 
 static void xlnx_ep108_init(MachineState *machine)
@@ -35,20 +32,12 @@ static void xlnx_ep108_init(MachineState *machine)
     XlnxEP108 *s = g_new0(XlnxEP108, 1);
     Error *err = NULL;
 
-    object_initialize(&s->soc, sizeof(s->soc), TYPE_XLNX_ZYNQMP);
-    object_property_add_child(OBJECT(machine), "soc", OBJECT(&s->soc),
-                              &error_abort);
-
-    object_property_set_bool(OBJECT(&s->soc), true, "realized", &err);
-    if (err) {
-        error_report("%s", error_get_pretty(err));
-        exit(1);
-    }
-
-    if (machine->ram_size > EP108_MAX_RAM_SIZE) {
+    /* Create the memory region to pass to the SoC */
+    if (machine->ram_size > XLNX_ZYNQMP_MAX_RAM_SIZE) {
         error_report("WARNING: RAM size " RAM_ADDR_FMT " above max supported, "
-                     "reduced to %llx", machine->ram_size, EP108_MAX_RAM_SIZE);
-        machine->ram_size = EP108_MAX_RAM_SIZE;
+                     "reduced to %llx", machine->ram_size,
+                     XLNX_ZYNQMP_MAX_RAM_SIZE);
+        machine->ram_size = XLNX_ZYNQMP_MAX_RAM_SIZE;
     }
 
     if (machine->ram_size < 0x08000000) {
@@ -56,9 +45,24 @@ static void xlnx_ep108_init(MachineState *machine)
                  machine->ram_size);
     }
 
-    memory_region_allocate_system_memory(&s->ddr_ram, NULL, "ddr-ram",
+    memory_region_allocate_system_memory(&s->ddr_board_ram, NULL,
+                                         "xlnx-zynqmp-board-ram",
                                          machine->ram_size);
-    memory_region_add_subregion(get_system_memory(), 0, &s->ddr_ram);
+
+    object_initialize(&s->soc, sizeof(s->soc), TYPE_XLNX_ZYNQMP);
+    object_property_add_child(OBJECT(machine), "soc", OBJECT(&s->soc),
+                              &error_abort);
+
+    object_property_set_int(OBJECT(&s->soc), machine->ram_size,
+                            "ram-size", &error_abort);
+    object_property_set_link(OBJECT(&s->soc), OBJECT(&s->ddr_board_ram),
+                         "xlnx-zynqmp-board-ram", &error_abort);
+
+    object_property_set_bool(OBJECT(&s->soc), true, "realized", &err);
+    if (err) {
+        error_report("%s", error_get_pretty(err));
+        exit(1);
+    }
 
     xlnx_ep108_binfo.ram_size = machine->ram_size;
     xlnx_ep108_binfo.kernel_filename = machine->kernel_filename;
diff --git a/hw/arm/xlnx-zynqmp.c b/hw/arm/xlnx-zynqmp.c
index 87553bb..848d1ff 100644
--- a/hw/arm/xlnx-zynqmp.c
+++ b/hw/arm/xlnx-zynqmp.c
@@ -90,6 +90,11 @@ static void xlnx_zynqmp_init(Object *obj)
                                   &error_abort);
     }
 
+    object_property_add_link(obj, "xlnx-zynqmp-board-ram", TYPE_MEMORY_REGION,
+                             (Object **)&s->ddr_board_ram,
+                             qdev_prop_allow_set_link_before_realize,
+                             OBJ_PROP_LINK_UNREF_ON_RELEASE, &error_abort);
+
     object_initialize(&s->gic, sizeof(s->gic), TYPE_ARM_GIC);
     qdev_set_parent_bus(DEVICE(&s->gic), sysbus_get_default());
 
@@ -120,9 +125,33 @@ static void xlnx_zynqmp_realize(DeviceState *dev, Error 
**errp)
     MemoryRegion *system_memory = get_system_memory();
     uint8_t i;
     const char *boot_cpu = s->boot_cpu ? s->boot_cpu : "apu-cpu[0]";
+    ram_addr_t ddr_low_size, ddr_high_size;
     qemu_irq gic_spi[GIC_NUM_SPI_INTR];
     Error *err = NULL;
 
+    /* Create the DDR Memory Regions */
+    if (s->ram_size > XLNX_ZYNQMP_MAX_LOW_RAM_SIZE) {
+        /* The RAM size is above the maximum avaliable for the low DDR.
+         * Create the high DDR memory region as well
+         */
+        ddr_low_size = XLNX_ZYNQMP_MAX_LOW_RAM_SIZE;
+        ddr_high_size = s->ram_size - XLNX_ZYNQMP_MAX_LOW_RAM_SIZE;
+
+        memory_region_init_alias(&s->ddr_ram_high, NULL,
+                                 "ddr-ram-high", s->ddr_board_ram,
+                                  ddr_low_size, ddr_high_size);
+        memory_region_add_subregion(get_system_memory(),
+                                    XLNX_ZYNQMP_HIGH_RAM_START,
+                                    &s->ddr_ram_high);
+    } else {
+        ddr_low_size = s->ram_size;
+    }
+
+    memory_region_init_alias(&s->ddr_ram_low, NULL,
+                             "ddr-ram-low", s->ddr_board_ram,
+                              0, ddr_low_size);
+    memory_region_add_subregion(get_system_memory(), 0, &s->ddr_ram_low);
+
     /* Create the four OCM banks */
     for (i = 0; i < XLNX_ZYNQMP_NUM_OCM_BANKS; i++) {
         char *ocm_name = g_strdup_printf("zynqmp.ocm_ram_bank_%d", i);
@@ -290,6 +319,8 @@ static void xlnx_zynqmp_realize(DeviceState *dev, Error 
**errp)
 
 static Property xlnx_zynqmp_props[] = {
     DEFINE_PROP_STRING("boot-cpu", XlnxZynqMPState, boot_cpu),
+    /* Needs to be set by the board, so default to an invalid number */
+    DEFINE_PROP_UINT64("ram-size", XlnxZynqMPState, ram_size, -1),
     DEFINE_PROP_END_OF_LIST()
 };
 
diff --git a/include/hw/arm/xlnx-zynqmp.h b/include/hw/arm/xlnx-zynqmp.h
index d116092..01eeadf 100644
--- a/include/hw/arm/xlnx-zynqmp.h
+++ b/include/hw/arm/xlnx-zynqmp.h
@@ -51,6 +51,14 @@
 #define XLNX_ZYNQMP_GIC_REGION_SIZE 0x1000
 #define XLNX_ZYNQMP_GIC_ALIASES     (0x10000 / XLNX_ZYNQMP_GIC_REGION_SIZE - 1)
 
+#define XLNX_ZYNQMP_MAX_LOW_RAM_SIZE    0x80000000ull
+
+#define XLNX_ZYNQMP_MAX_HIGH_RAM_SIZE   0x800000000ull
+#define XLNX_ZYNQMP_HIGH_RAM_START      0x800000000ull
+
+#define XLNX_ZYNQMP_MAX_RAM_SIZE (XLNX_ZYNQMP_MAX_LOW_RAM_SIZE + \
+                                  XLNX_ZYNQMP_MAX_HIGH_RAM_SIZE)
+
 typedef struct XlnxZynqMPState {
     /*< private >*/
     DeviceState parent_obj;
@@ -60,7 +68,11 @@ typedef struct XlnxZynqMPState {
     ARMCPU rpu_cpu[XLNX_ZYNQMP_NUM_RPU_CPUS];
     GICState gic;
     MemoryRegion gic_mr[XLNX_ZYNQMP_GIC_REGIONS][XLNX_ZYNQMP_GIC_ALIASES];
+
     MemoryRegion ocm_ram[XLNX_ZYNQMP_NUM_OCM_BANKS];
+    uint64 ram_size;
+    MemoryRegion *ddr_board_ram;
+    MemoryRegion ddr_ram_low, ddr_ram_high;
 
     CadenceGEMState gem[XLNX_ZYNQMP_NUM_GEMS];
     CadenceUARTState uart[XLNX_ZYNQMP_NUM_UARTS];
-- 
2.5.0