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/*

 * bat.c

 *

 *          This file contains the implementation of C function to

 *          Instanciate 60x/7xx ppc Block Address Translation (BAT) registers.

 *          More detailled information can be found on motorola

 *          site and more precisely in the following book :

 *

 *              MPC750

 *              Risc Microporcessor User's Manual

 *              Mtorola REF : MPC750UM/AD 8/97

 *

 * Copyright (C) 1999  Eric Valette (valette@crf.canon.fr)

 *                     Canon Centre Recherche France.

 *

 *  The license and distribution terms for this file may be

 *  found in found in the file LICENSE in this distribution or at

 *  http://www.OARcorp.com/rtems/license.html.

 *

 * $Id: bat.c,v 1.2 2001-09-27 12:01:25 chris Exp $

 */

#include <libcpu/bat.h>

typedef union {                 /* BAT register values to be loaded */

        BAT             bat;

        unsigned int    word[2];

}ubat;

typedef struct batrange {               /* stores address ranges mapped by BATs */

        unsigned long start;

        unsigned long limit;

        unsigned long phys;

}batrange;

batrange bat_addrs[4];

void setdbat(int bat_index, unsigned long virt, unsigned long phys,

       unsigned int size, int flags)

{

  unsigned int bl;

  int wimgxpp;

  ubat bat;

  bl = (size >> 17) - 1;

  /* 603, 604, etc. */

  wimgxpp = flags & (_PAGE_WRITETHRU | _PAGE_NO_CACHE

                     | _PAGE_COHERENT | _PAGE_GUARDED);

  wimgxpp |= (flags & _PAGE_RW)? BPP_RW: BPP_RX;

  bat.word[0] = virt | (bl << 2) | 2; /* Vs=1, Vp=0 */

  bat.word[1] = phys | wimgxpp;

  if (flags & _PAGE_USER)

    bat.bat.batu.vp = 1;

  bat_addrs[bat_index].start = virt;

  bat_addrs[bat_index].limit = virt + ((bl + 1) << 17) - 1;

  bat_addrs[bat_index].phys = phys;

  switch (bat_index) {

  case 1 : asm_setdbat1(bat.word[0], bat.word[1]); break;

  case 2 : asm_setdbat2(bat.word[0], bat.word[1]); break;

  case 3 : asm_setdbat3(bat.word[0], bat.word[1]); break;

  default: printk("bat.c : invalid BAT bat_index\n");

  }

}