ppc/e500: use memdev for RAM

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.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200219160953.13771-60-imammedo@redhat.com>

hw/ppc/e500.c

@@ -831,7 +831,6 @@ static void ppce500_power_off(void *opaque, int line, int on)
 void ppce500_init(MachineState *machine)
 {
     MemoryRegion *address_space_mem = get_system_memory();
-    MemoryRegion *ram = g_new(MemoryRegion, 1);
     PPCE500MachineState *pms = PPCE500_MACHINE(machine);
     const PPCE500MachineClass *pmc = PPCE500_MACHINE_GET_CLASS(machine);
     PCIBus *pci_bus;
@@ -912,9 +911,7 @@ void ppce500_init(MachineState *machine)
     }
 
     /* Register Memory */
-    memory_region_allocate_system_memory(ram, NULL, "mpc8544ds.ram",
-                                         machine->ram_size);
-    memory_region_add_subregion(address_space_mem, 0, ram);
+    memory_region_add_subregion(address_space_mem, 0, machine->ram);
 
     dev = qdev_create(NULL, "e500-ccsr");
     object_property_add_child(qdev_get_machine(), "e500-ccsr",

hw/ppc/e500plat.c

@@ -97,6 +97,7 @@ static void e500plat_machine_class_init(ObjectClass *oc, void *data)
     mc->init = e500plat_init;
     mc->max_cpus = 32;
     mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("e500v2_v30");
+    mc->default_ram_id = "mpc8544ds.ram";
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_ETSEC_COMMON);
  }
 

hw/ppc/mpc8544ds.c

@@ -55,6 +55,7 @@ static void e500plat_machine_class_init(ObjectClass *oc, void *data)
     mc->init = mpc8544ds_init;
     mc->max_cpus = 15;
     mc->default_cpu_type = POWERPC_CPU_TYPE_NAME("e500v2_v30");
+    mc->default_ram_id = "mpc8544ds.ram";
 }
 
 #define TYPE_MPC8544DS_MACHINE  MACHINE_TYPE_NAME("mpc8544ds")