memory_region_allocate_system_memory() API is going away, so
replace it with memdev allocated MemoryRegion. The later is
initialized by generic code, so board only needs to opt in
to memdev scheme by providing
  MachineClass::default_ram_id
and using MachineState::ram instead of manually initializing
RAM memory region.

PS:
 while at it add check for user supplied RAM size and error
 out if it mismatches board expected value.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
 hw/arm/nseries.c | 31 ++++++++++++++++++-------------
 1 file changed, 18 insertions(+), 13 deletions(-)

diff --git a/hw/arm/nseries.c b/hw/arm/nseries.c
index 3fd196f..89e4627 100644
--- a/hw/arm/nseries.c
+++ b/hw/arm/nseries.c
@@ -47,7 +47,6 @@
 
 /* Nokia N8x0 support */
 struct n800_s {
-    MemoryRegion sdram;
     struct omap_mpu_state_s *mpu;
 
     struct rfbi_chip_s blizzard;
@@ -1311,13 +1310,18 @@ static void n8x0_init(MachineState *machine,
                       struct arm_boot_info *binfo, int model)
 {
     struct n800_s *s = (struct n800_s *) g_malloc0(sizeof(*s));
-    uint64_t sdram_size = binfo->ram_size;
+    MachineClass *mc = MACHINE_GET_CLASS(machine);
 
-    memory_region_allocate_system_memory(&s->sdram, NULL, "omap2.dram",
-                                         sdram_size);
-    memory_region_add_subregion(get_system_memory(), OMAP2_Q2_BASE, &s->sdram);
+    if (machine->ram_size != mc->default_ram_size) {
+        error_report("Invalid RAM size, should be %" PRIi64 " Bytes",
+                     mc->default_ram_size);
+        exit(EXIT_FAILURE);
+    }
+
+    memory_region_add_subregion(get_system_memory(), OMAP2_Q2_BASE,
+                                machine->ram);
 
-    s->mpu = omap2420_mpu_init(&s->sdram, machine->cpu_type);
+    s->mpu = omap2420_mpu_init(machine->ram, machine->cpu_type);
 
     /* Setup peripherals
      *
@@ -1383,9 +1387,8 @@ static void n8x0_init(MachineState *machine,
          *
          * The code above is for loading the `zImage' file from Nokia
          * images.  */
-        load_image_targphys(option_rom[0].name,
-                            OMAP2_Q2_BASE + 0x400000,
-                            sdram_size - 0x400000);
+        load_image_targphys(option_rom[0].name, OMAP2_Q2_BASE + 0x400000,
+                            machine->ram_size - 0x400000);
 
         n800_setup_nolo_tags(nolo_tags);
         cpu_physical_memory_write(OMAP2_SRAM_BASE, nolo_tags, 0x10000);
@@ -1395,16 +1398,12 @@ static void n8x0_init(MachineState *machine,
 
 static struct arm_boot_info n800_binfo = {
     .loader_start = OMAP2_Q2_BASE,
-    /* Actually two chips of 0x4000000 bytes each */
-    .ram_size = 0x08000000,
     .board_id = 0x4f7,
     .atag_board = n800_atag_setup,
 };
 
 static struct arm_boot_info n810_binfo = {
     .loader_start = OMAP2_Q2_BASE,
-    /* Actually two chips of 0x4000000 bytes each */
-    .ram_size = 0x08000000,
     /* 0x60c and 0x6bf (WiMAX Edition) have been assigned but are not
      * used by some older versions of the bootloader and 5555 is used
      * instead (including versions that shipped with many devices).  */
@@ -1431,6 +1430,9 @@ static void n800_class_init(ObjectClass *oc, void *data)
     mc->default_boot_order = "";
     mc->ignore_memory_transaction_failures = true;
     mc->default_cpu_type = ARM_CPU_TYPE_NAME("arm1136-r2");
+    /* Actually two chips of 0x4000000 bytes each */
+    mc->default_ram_size = 0x08000000;
+    mc->default_ram_id = "omap2.dram";
 }
 
 static const TypeInfo n800_type = {
@@ -1448,6 +1450,9 @@ static void n810_class_init(ObjectClass *oc, void *data)
     mc->default_boot_order = "";
     mc->ignore_memory_transaction_failures = true;
     mc->default_cpu_type = ARM_CPU_TYPE_NAME("arm1136-r2");
+    /* Actually two chips of 0x4000000 bytes each */
+    mc->default_ram_size = 0x08000000;
+    mc->default_ram_id = "omap2.dram";
 }
 
 static const TypeInfo n810_type = {
-- 
2.7.4