func: void *pl080_init(uint32_t base, qemu_irq irq, int nchannels)
  
  {
  
      int iomemtype;
  
      pl080_state *s;
  
  
  
      s = (pl080_state *)qemu_mallocz(sizeof(pl080_state));
  
      iomemtype = cpu_register_io_memory(0, pl080_readfn,
  
                                         pl080_writefn, s);
  
      cpu_register_physical_memory(base, 0x00000fff, iomemtype);
  
      s->base = base;
  
      s->irq = irq;
  
      s->nchannels = nchannels;
  
      /* ??? Save/restore.  */
  
      return s;
  
  }
  