rom loader: make vga+rom loading configurable.

The rom_add_vga() and rom_add_option() macros are transformed into
functions.  They look at the new rom_enable_driver_roms variable
and only do something if it is set to non-zero, making vga+option rom
loading runtime option.  pc_init() sets rom_enable_driver_roms to 1.

With this in place we can move the rom loading calls from pc.c to the
individual drivers.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

hw/loader.c

@@ -534,6 +534,7 @@ struct Rom {
 };
 
 static QTAILQ_HEAD(, Rom) roms = QTAILQ_HEAD_INITIALIZER(roms);
+int rom_enable_driver_roms;
 
 static void rom_insert(Rom *rom)
 {
@@ -612,6 +613,20 @@ int rom_add_blob(const char *name, const void *blob, size_t len,
     return 0;
 }
 
+int rom_add_vga(const char *file)
+{
+    if (!rom_enable_driver_roms)
+        return 0;
+    return rom_add_file(file, PC_ROM_MIN_VGA, PC_ROM_MAX, PC_ROM_ALIGN);
+}
+
+int rom_add_option(const char *file)
+{
+    if (!rom_enable_driver_roms)
+        return 0;
+    return rom_add_file(file, PC_ROM_MIN_OPTION, PC_ROM_MAX, PC_ROM_ALIGN);
+}
+
 static void rom_reset(void *unused)
 {
     Rom *rom;

hw/loader.h

@@ -38,9 +38,8 @@ void do_info_roms(Monitor *mon);
 #define PC_ROM_ALIGN       0x800
 #define PC_ROM_SIZE        (PC_ROM_MAX - PC_ROM_MIN_VGA)
 
-#define rom_add_vga(_f)                                                 \
-    rom_add_file(_f, PC_ROM_MIN_VGA,    PC_ROM_MAX, PC_ROM_ALIGN)
-#define rom_add_option(_f)                                              \
-    rom_add_file(_f, PC_ROM_MIN_OPTION, PC_ROM_MAX, PC_ROM_ALIGN)
+extern int rom_enable_driver_roms;
+int rom_add_vga(const char *file);
+int rom_add_option(const char *file);
 
 #endif

hw/pc.c

@@ -1137,6 +1137,7 @@ static void pc_init1(ram_addr_t ram_size,
 
 
 
+    rom_enable_driver_roms = 1;
     option_rom_offset = qemu_ram_alloc(PC_ROM_SIZE);
     cpu_register_physical_memory(PC_ROM_MIN_VGA, PC_ROM_SIZE, option_rom_offset);