Subversion Repositories openrisc_2011-10-31

/* cygmon.c -- Glue code for linking apps to run on top of Cygmon.

 *

 * Copyright (c) 1998, 1999, 2000, 2001 Red Hat, Inc.

 *

 * The authors hereby grant permission to use, copy, modify, distribute,

 * and license this software and its documentation for any purpose, provided

 * that existing copyright notices are retained in all copies and that this

 * notice is included verbatim in any distributions. No written agreement,

 * license, or royalty fee is required for any of the authorized uses.

 * Modifications to this software may be copyrighted by their authors

 * and need not follow the licensing terms described here, provided that

 * the new terms are clearly indicated on the first page of each file where

 * they apply.

 */

#include <errno.h>

// These need to be kept in sync with the definitions in Cygmon.

#define SYS_meminfo     1001

#include "syscall.h"

/* Structure filled in by get_mem_info.  Only the size field is

   actually used (by sbrk), so the others aren't even filled in.  */

struct s_mem

{

  unsigned int size;

  unsigned int icsize;

  unsigned int dcsize;

};

// Perform a system call.

// Unused parameters should be set to 0.

int __trap0(unsigned long func, unsigned long p1, unsigned long p2, unsigned long p3)

{

  int ret = 0;

#ifdef __AM33__

  {

    register unsigned long d0 asm ("d0") = func;

    register unsigned long d1 asm ("d1") = p1;

    register unsigned long d2 asm ("d2") = p2;

    register unsigned long d3 asm ("d3") = p3;

    asm volatile ("    syscall 0\n"

                  "    nop"

                  : "+d" (d0) : "d" (d1), "d" (d2), "d" (d3) : "memory");

    ret = d0;

  }

#endif

  if (func == SYS_exit)

    {

      while (1)

        {

          asm volatile (" .byte 0xff ");  // trigger a breakpoint to drop back into Cygmon

        }

    }

  if (ret != 0)

      errno = ret;

  return ret;

}

void *

get_mem_info (mem)

     struct s_mem *mem;

{

  unsigned long totmem = 0, topmem = 0;

  register int numbanks;

  numbanks = __trap0(SYS_meminfo, (unsigned long)&totmem, (unsigned long)&topmem, 0);

  mem->size = totmem;

  return (void*)topmem;

}