Logo Search packages:      
Sourcecode: linux version File versions  Download package

claim.c

/*
 * Copyright (C) Paul Mackerras 1997.
 * Copyright (C) Leigh Brown 2002.
 *
 * This program 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
 * 2 of the License, or (at your option) any later version.
 */

#include "of1275.h"
#include "nonstdio.h"

/*
 * Older OF's require that when claiming a specific range of addresses,
 * we claim the physical space in the /memory node and the virtual
 * space in the chosen mmu node, and then do a map operation to
 * map virtual to physical.
 */
static int need_map = -1;
static ihandle chosen_mmu;
static phandle memory;

/* returns true if s2 is a prefix of s1 */
static int string_match(const char *s1, const char *s2)
{
      for (; *s2; ++s2)
            if (*s1++ != *s2)
                  return 0;
      return 1;
}

static int check_of_version(void)
{
      phandle oprom, chosen;
      char version[64];

      oprom = finddevice("/openprom");
      if (oprom == OF_INVALID_HANDLE)
            return 0;
      if (getprop(oprom, "model", version, sizeof(version)) <= 0)
            return 0;
      version[sizeof(version)-1] = 0;
      printf("OF version = '%s'\n", version);
      if (!string_match(version, "Open Firmware, 1.")
          && !string_match(version, "FirmWorks,3."))
            return 0;
      chosen = finddevice("/chosen");
      if (chosen == OF_INVALID_HANDLE) {
            chosen = finddevice("/chosen@0");
            if (chosen == OF_INVALID_HANDLE) {
                  printf("no chosen\n");
                  return 0;
            }
      }
      if (getprop(chosen, "mmu", &chosen_mmu, sizeof(chosen_mmu)) <= 0) {
            printf("no mmu\n");
            return 0;
      }
      memory = (ihandle) call_prom("open", 1, 1, "/memory");
      if (memory == OF_INVALID_HANDLE) {
            memory = (ihandle) call_prom("open", 1, 1, "/memory@0");
            if (memory == OF_INVALID_HANDLE) {
                  printf("no memory node\n");
                  return 0;
            }
      }
      printf("old OF detected\n");
      return 1;
}

void *claim(unsigned int virt, unsigned int size, unsigned int align)
{
      int ret;
      unsigned int result;

      if (need_map < 0)
            need_map = check_of_version();
      if (align || !need_map)
            return (void *) call_prom("claim", 3, 1, virt, size, align);
      
      ret = call_prom_ret("call-method", 5, 2, &result, "claim", memory,
                      align, size, virt);
      if (ret != 0 || result == -1)
            return (void *) -1;
      ret = call_prom_ret("call-method", 5, 2, &result, "claim", chosen_mmu,
                      align, size, virt);
      /* 0x12 == coherent + read/write */
      ret = call_prom("call-method", 6, 1, "map", chosen_mmu,
                  0x12, size, virt, virt);
      return virt;
}

Generated by  Doxygen 1.6.0   Back to index