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/* Trampoline support for MeP

   Copyright (C) 2004, 2007 Free Software Foundation, Inc.

   Contributed by Red Hat Inc.

This file is free software; you can redistribute it and/or modify it

under the terms of the GNU General Public License as published by the

Free Software Foundation; either version 3 of the License, or (at your

option) any later version.

This file is distributed in the hope that it will be useful, but

WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

General Public License for more details.

Under Section 7 of GPL version 3, you are granted additional

permissions described in the GCC Runtime Library Exception, version

3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and

a copy of the GCC Runtime Library Exception along with this program;

see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see

<http://www.gnu.org/licenses/>.  */

/*

  7a0a          ldc $10,$pc

  c0ae000a      lw $0,10($10)

  caae000e      lw $10,14($10)

  10ae          jmp $10

  00000000      static chain

  00000000      function address

*/

static inline int

cache_config_register(void) {

  int rv;

  asm ("ldc\t%0, $ccfg" : "=r" (rv));

  return rv;

}

#define ICACHE_SIZE ((cache_config_register() >> 16) & 0x7f)

#define DCACHE_SIZE (cache_config_register() & 0x7f)

#define ICACHE_DATA_BASE 0x00300000

#define ICACHE_TAG_BASE  0x00310000

#define DCACHE_DATA_BASE 0x00320000

#define DCACHE_TAG_BASE  0x00330000

static inline void

flush_dcache (int addr)

{

  asm volatile ("cache\t0, (%0)" : : "r" (addr));

}

void

__mep_trampoline_helper (unsigned long *tramp,

                         int function_address,

                         int static_chain);

void

__mep_trampoline_helper (unsigned long *tramp,

                         int function_address,

                         int static_chain)

{

  int dsize, isize;

#ifdef __LITTLE_ENDIAN__

  tramp[0] = 0xc0ae7a0a;

  tramp[1] = 0xcaae000a;

  tramp[2] = 0x10ae000e;

#else

  tramp[0] = 0x7a0ac0ae;

  tramp[1] = 0x000acaae;

  tramp[2] = 0x000e10ae;

#endif

  tramp[3] = static_chain;

  tramp[4] = function_address;

  dsize = DCACHE_SIZE;

  isize = ICACHE_SIZE;

  if (dsize)

    {

      flush_dcache ((int)tramp);

      flush_dcache ((int)tramp+16);

    }

  if (isize)

    {

      int imask = (isize * 1024) - 1;

      int tmask = ~imask;

      unsigned int i;

      volatile unsigned int *tags;

      imask &= 0xffe0;

      for (i=(unsigned int)tramp; i<(unsigned int)tramp+20; i+=16)

        {

          tags = (unsigned int *)(ICACHE_TAG_BASE + (i & imask));

          if ((*tags & tmask) == (i & tmask))

            *tags &= ~1;

        }

    }

}