ppc/ppc405_boards: 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.

PS:
in ref405ep alias RAM into ram_memories[] to avoid re-factoring
its user ppc405ep_init(), which would be invasive and out of
scope this patch.

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: <20200219160953.13771-65-imammedo@redhat.com>

hw/ppc/ppc405_boards.c

@@ -170,8 +170,8 @@ static void ref405ep_init(MachineState *machine)
     }
 
     /* XXX: fix this */
-    memory_region_allocate_system_memory(&ram_memories[0], NULL, "ef405ep.ram",
-                                         machine->ram_size);
+    memory_region_init_alias(&ram_memories[0], NULL, "ef405ep.ram.alias",
+                             machine->ram, 0, machine->ram_size);
     ram_bases[0] = 0;
     ram_sizes[0] = machine->ram_size;
     memory_region_init(&ram_memories[1], NULL, "ef405ep.ram1", 0);
@@ -312,6 +312,7 @@ static void ref405ep_class_init(ObjectClass *oc, void *data)
     mc->desc = "ref405ep";
     mc->init = ref405ep_init;
     mc->default_ram_size = 0x08000000;
+    mc->default_ram_id = "ef405ep.ram";
 }
 
 static const TypeInfo ref405ep_type = {
@@ -424,7 +425,6 @@ static void taihu_405ep_init(MachineState *machine)
     MemoryRegion *sysmem = get_system_memory();
     MemoryRegion *bios;
     MemoryRegion *ram_memories = g_new(MemoryRegion, 2);
-    MemoryRegion *ram = g_malloc0(sizeof(*ram));
     hwaddr ram_bases[2], ram_sizes[2];
     long bios_size;
     target_ulong kernel_base, initrd_base;
@@ -439,18 +439,16 @@ static void taihu_405ep_init(MachineState *machine)
         g_free(sz);
         exit(EXIT_FAILURE);
     }
-    memory_region_allocate_system_memory(ram, NULL, "taihu_405ep.ram",
-                                         machine->ram_size);
 
     ram_bases[0] = 0;
     ram_sizes[0] = 0x04000000;
     memory_region_init_alias(&ram_memories[0], NULL,
-                             "taihu_405ep.ram-0", ram, ram_bases[0],
+                             "taihu_405ep.ram-0", machine->ram, ram_bases[0],
                              ram_sizes[0]);
     ram_bases[1] = 0x04000000;
     ram_sizes[1] = 0x04000000;
     memory_region_init_alias(&ram_memories[1], NULL,
-                             "taihu_405ep.ram-1", ram, ram_bases[1],
+                             "taihu_405ep.ram-1", machine->ram, ram_bases[1],
                              ram_sizes[1]);
     ppc405ep_init(sysmem, ram_memories, ram_bases, ram_sizes,
                   33333333, &pic, kernel_filename == NULL ? 0 : 1);
@@ -546,6 +544,7 @@ static void taihu_class_init(ObjectClass *oc, void *data)
     mc->desc = "taihu";
     mc->init = taihu_405ep_init;
     mc->default_ram_size = 0x08000000;
+    mc->default_ram_id = "taihu_405ep.ram";
 }
 
 static const TypeInfo taihu_type = {