release/src-rt-6.x.4708/linux/linux-2.6.36/arch/powerpc/boot/of.c

   1 /*
   2  * Copyright (C) Paul Mackerras 1997.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  */
   9 #include <stdarg.h>
  10 #include <stddef.h>
  11 #include "types.h"
  12 #include "elf.h"
  13 #include "string.h"
  14 #include "stdio.h"
  15 #include "page.h"
  16 #include "ops.h"
  17
  18 #include "of.h"
  19
  20 /* Value picked to match that used by yaboot */
  21 #define PROG_START      0x01400000      /* only used on 64-bit systems */
  22 #define RAM_END         (512<<20)
  23 #define ONE_MB          0x100000
  24
  25
  26
  27 static unsigned long claim_base;
  28
  29 static void *of_try_claim(unsigned long size)
  30 {
  31         unsigned long addr = 0;
  32
  33         if (claim_base == 0)
  34                 claim_base = _ALIGN_UP((unsigned long)_end, ONE_MB);
  35
  36         for(; claim_base < RAM_END; claim_base += ONE_MB) {
  37 #ifdef DEBUG
  38                 printf("    trying: 0x%08lx\n\r", claim_base);
  39 #endif
  40                 addr = (unsigned long)of_claim(claim_base, size, 0);
  41                 if ((void *)addr != (void *)-1)
  42                         break;
  43         }
  44         if (addr == 0)
  45                 return NULL;
  46         claim_base = PAGE_ALIGN(claim_base + size);
  47         return (void *)addr;
  48 }
  49
  50 static void of_image_hdr(const void *hdr)
  51 {
  52         const Elf64_Ehdr *elf64 = hdr;
  53
  54         if (elf64->e_ident[EI_CLASS] == ELFCLASS64) {
  55                 /*
  56                  * Maintain a "magic" minimum address. This keeps some older
  57                  * firmware platforms running.
  58                  */
  59                 if (claim_base < PROG_START)
  60                         claim_base = PROG_START;
  61         }
  62 }
  63
  64 void platform_init(unsigned long a1, unsigned long a2, void *promptr)
  65 {
  66         platform_ops.image_hdr = of_image_hdr;
  67         platform_ops.malloc = of_try_claim;
  68         platform_ops.exit = of_exit;
  69         platform_ops.vmlinux_alloc = of_vmlinux_alloc;
  70
  71         dt_ops.finddevice = of_finddevice;
  72         dt_ops.getprop = of_getprop;
  73         dt_ops.setprop = of_setprop;
  74
  75         of_console_init();
  76
  77         of_init(promptr);
  78         loader_info.promptr = promptr;
  79         if (a1 && a2 && a2 != 0xdeadbeef) {
  80                 loader_info.initrd_addr = a1;
  81                 loader_info.initrd_size = a2;
  82         }
  83 }