static unsigned pci_locate_device(unsigned addr) { addr &= ~0xff; for(; addr <= 0x00ffff00; addr += 0x00000100) { __builtin_outl(addr, 0x12); } return addr; } static void main(void) { unsigned long addr; addr = pci_locate_device(0); __builtin_outl(addr, 0x12); }