rx: move BIOS load from MCU to board

The ROM loader state is global and not part of the MCU, and the
BIOS is in machine->firmware.  So just like the kernel case,
load it in the board.

Due to the ordering between CPU reset and ROM reset, the ROM
has to be registered before the CPU is realized, otherwise
the reset vector is loaded before the ROM is there.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

hw/rx/rx-gdbsim.c

@@ -106,6 +106,16 @@ static void rx_gdbsim_init(MachineState *machine)
                              rxc->xtal_freq_hz, &error_abort);
     object_property_set_bool(OBJECT(&s->mcu), "load-kernel",
                              kernel_filename != NULL, &error_abort);
+
+    if (!kernel_filename) {
+        if (machine->firmware) {
+            rom_add_file_fixed(machine->firmware, RX62N_CFLASH_BASE, 0);
+        } else if (!qtest_enabled()) {
+            error_report("No bios or kernel specified");
+            exit(1);
+        }
+    }
+
     qdev_realize(DEVICE(&s->mcu), NULL, &error_abort);
 
     /* Load kernel and dtb */

hw/rx/rx62n.c

@@ -245,15 +245,6 @@ static void rx62n_realize(DeviceState *dev, Error **errp)
                            rxc->rom_flash_size, &error_abort);
     memory_region_add_subregion(s->sysmem, RX62N_CFLASH_BASE, &s->c_flash);
 
-    if (!s->kernel) {
-        if (bios_name) {
-            rom_add_file_fixed(bios_name, RX62N_CFLASH_BASE, 0);
-        }  else if (!qtest_enabled()) {
-            error_report("No bios or kernel specified");
-            exit(1);
-        }
-    }
-
     /* Initialize CPU */
     object_initialize_child(OBJECT(s), "cpu", &s->cpu, TYPE_RX62N_CPU);
     qdev_realize(DEVICE(&s->cpu), NULL, &error_abort);