int sceSetCpuClockFrequency(int cpu, int ram, int bus)
// cpu = 1 - 333
// ram = 1 - 333
// bus = 1 - 167
{
  register int lret asm("$2");
  register int lcpu asm("$4") = cpu;
  register int lram asm("$5") = ram;
  register int lbus asm("$6") = bus;

  asm("syscall 0x21A7"
      : "=r" (lret)
      : "r" (lcpu), "r" (lram), "r" (lbus)
      );

  return(lret);
}