arch/common/boot/grub2/kern/i386/pc/init.c

   1 /*
   2  *  GRUB  --  GRand Unified Bootloader
   3  *  Copyright (C) 2002,2003,2004,2005,2006,2007,2008  Free Software Foundation, Inc.
   4  *
   5  *  GRUB is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  GRUB is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <grub/kernel.h>
  20 #include <grub/mm.h>
  21 #include <grub/machine/init.h>
  22 #include <grub/machine/memory.h>
  23 #include <grub/machine/console.h>
  24 #include <grub/machine/kernel.h>
  25 #include <grub/types.h>
  26 #include <grub/err.h>
  27 #include <grub/dl.h>
  28 #include <grub/misc.h>
  29 #include <grub/loader.h>
  30 #include <grub/env.h>
  31 #include <grub/cache.h>
  32 #include <grub/time.h>
  33
  34 struct mem_region
  35 {
  36   grub_addr_t addr;
  37   grub_size_t size;
  38 };
  39
  40 #define MAX_REGIONS     32
  41
  42 static struct mem_region mem_regions[MAX_REGIONS];
  43 static int num_regions;
  44
  45 grub_addr_t grub_os_area_addr;
  46 grub_size_t grub_os_area_size;
  47 grub_size_t grub_lower_mem, grub_upper_mem;
  48
  49 void
  50 grub_millisleep (grub_uint32_t ms)
  51 {
  52   grub_millisleep_generic (ms);
  53 }
  54
  55 void
  56 grub_arch_sync_caches (void *address __attribute__ ((unused)),
  57                        grub_size_t len __attribute__ ((unused)))
  58 {
  59 }
  60
  61 static char *
  62 make_install_device (void)
  63 {
  64   /* XXX: This should be enough.  */
  65   char dev[100];
  66
  67   if (grub_memdisk_image_size)
  68     {
  69       grub_sprintf (dev, "(memdisk)%s", grub_prefix);
  70       grub_strcpy (grub_prefix, dev);
  71     }
  72   else if (grub_install_dos_part != -2)
  73     {
  74       /* If the root drive is not set explicitly, assume that it is identical
  75          to the boot drive.  */
  76       if (grub_root_drive == 0xFF)
  77         grub_root_drive = grub_boot_drive;
  78
  79       grub_sprintf (dev, "(%cd%u", (grub_root_drive & 0x80) ? 'h' : 'f',
  80                     grub_root_drive & 0x7f);
  81
  82       if (grub_install_dos_part >= 0)
  83         grub_sprintf (dev + grub_strlen (dev), ",%u", grub_install_dos_part + 1);
  84
  85       if (grub_install_bsd_part >= 0)
  86         grub_sprintf (dev + grub_strlen (dev), ",%c", grub_install_bsd_part + 'a');
  87
  88       grub_sprintf (dev + grub_strlen (dev), ")%s", grub_prefix);
  89       grub_strcpy (grub_prefix, dev);
  90     }
  91
  92   return grub_prefix;
  93 }
  94
  95 /* Add a memory region.  */
  96 static void
  97 add_mem_region (grub_addr_t addr, grub_size_t size)
  98 {
  99   if (num_regions == MAX_REGIONS)
 100     /* Ignore.  */
 101     return;
 102
 103   mem_regions[num_regions].addr = addr;
 104   mem_regions[num_regions].size = size;
 105   num_regions++;
 106 }
 107
 108 /* Compact memory regions.  */
 109 static void
 110 compact_mem_regions (void)
 111 {
 112   int i, j;
 113
 114   /* Sort them.  */
 115   for (i = 0; i < num_regions - 1; i++)
 116     for (j = i + 1; j < num_regions; j++)
 117       if (mem_regions[i].addr > mem_regions[j].addr)
 118         {
 119           struct mem_region tmp = mem_regions[i];
 120           mem_regions[i] = mem_regions[j];
 121           mem_regions[j] = tmp;
 122         }
 123
 124   /* Merge overlaps.  */
 125   for (i = 0; i < num_regions - 1; i++)
 126     if (mem_regions[i].addr + mem_regions[i].size >= mem_regions[i + 1].addr)
 127       {
 128         j = i + 1;
 129
 130         if (mem_regions[i].addr + mem_regions[i].size
 131             < mem_regions[j].addr + mem_regions[j].size)
 132           mem_regions[i].size = (mem_regions[j].addr + mem_regions[j].size
 133                                  - mem_regions[i].addr);
 134
 135         grub_memmove (mem_regions + j, mem_regions + j + 1,
 136                       (num_regions - j - 1) * sizeof (struct mem_region));
 137         i--;
 138         num_regions--;
 139       }
 140 }
 141
 142 void
 143 grub_machine_init (void)
 144 {
 145   grub_uint32_t cont;
 146   struct grub_machine_mmap_entry *entry
 147     = (struct grub_machine_mmap_entry *) GRUB_MEMORY_MACHINE_SCRATCH_ADDR;
 148   int i;
 149
 150   /* Initialize the console as early as possible.  */
 151   grub_console_init ();
 152
 153   grub_lower_mem = grub_get_memsize (0) << 10;
 154
 155   /* Sanity check.  */
 156   if (grub_lower_mem < GRUB_MEMORY_MACHINE_RESERVED_END)
 157     grub_fatal ("too small memory");
 158
 159 #if 0
 160   /* Turn on Gate A20 to access >1MB.  */
 161   grub_gate_a20 (1);
 162 #endif
 163
 164   /* Add the lower memory into free memory.  */
 165   if (grub_lower_mem >= GRUB_MEMORY_MACHINE_RESERVED_END)
 166     add_mem_region (GRUB_MEMORY_MACHINE_RESERVED_END,
 167                     grub_lower_mem - GRUB_MEMORY_MACHINE_RESERVED_END);
 168
 169   /* Check if grub_get_mmap_entry works.  */
 170   cont = grub_get_mmap_entry (entry, 0);
 171
 172   if (entry->size)
 173     do
 174       {
 175         /* Avoid the lower memory.  */
 176         if (entry->addr < 0x100000)
 177           {
 178             if (entry->len <= 0x100000 - entry->addr)
 179               goto next;
 180
 181             entry->len -= 0x100000 - entry->addr;
 182             entry->addr = 0x100000;
 183           }
 184
 185         /* Ignore >4GB.  */
 186         if (entry->addr <= 0xFFFFFFFF && entry->type == 1)
 187           {
 188             grub_addr_t addr;
 189             grub_size_t len;
 190
 191             addr = (grub_addr_t) entry->addr;
 192             len = ((addr + entry->len > 0xFFFFFFFF)
 193                    ? 0xFFFFFFFF - addr
 194                    : (grub_size_t) entry->len);
 195             add_mem_region (addr, len);
 196           }
 197
 198       next:
 199         if (! cont)
 200           break;
 201
 202         cont = grub_get_mmap_entry (entry, cont);
 203       }
 204     while (entry->size);
 205   else
 206     {
 207       grub_uint32_t eisa_mmap = grub_get_eisa_mmap ();
 208
 209       if (eisa_mmap)
 210         {
 211           add_mem_region (0x100000, (eisa_mmap & 0xFFFF) << 10);
 212           add_mem_region (0x1000000, eisa_mmap & ~0xFFFF);
 213         }
 214       else
 215         add_mem_region (0x100000, grub_get_memsize (1) << 10);
 216     }
 217
 218   compact_mem_regions ();
 219
 220   /* Add the memory regions to free memory, except for the region starting
 221      from 1MB. This region is partially used for loading OS images.
 222      For now, 1/4 of this is added to free memory.  */
 223   for (i = 0; i < num_regions; i++)
 224     if (mem_regions[i].addr == 0x100000)
 225       {
 226         grub_size_t quarter = mem_regions[i].size >> 2;
 227
 228         grub_upper_mem = mem_regions[i].size;
 229         grub_os_area_addr = mem_regions[i].addr;
 230         grub_os_area_size = mem_regions[i].size - quarter;
 231         grub_mm_init_region ((void *) (grub_os_area_addr + grub_os_area_size),
 232                              quarter);
 233       }
 234     else
 235       grub_mm_init_region ((void *) mem_regions[i].addr, mem_regions[i].size);
 236
 237   if (! grub_os_area_addr)
 238     grub_fatal ("no upper memory");
 239 }
 240
 241 void
 242 grub_machine_set_prefix (void)
 243 {
 244   /* Initialize the prefix.  */
 245   grub_env_set ("prefix", make_install_device ());
 246 }
 247
 248 void
 249 grub_machine_fini (void)
 250 {
 251   grub_console_fini ();
 252 }
 253
 254 /* Return the end of the core image.  */
 255 grub_addr_t
 256 grub_arch_modules_addr (void)
 257 {
 258   return grub_end_addr;
 259 }
 260
 261 /* Return the start of the memdisk image.  */
 262 grub_addr_t
 263 grub_arch_memdisk_addr (void)
 264 {
 265   return GRUB_MEMORY_MACHINE_DECOMPRESSION_ADDR
 266     + (grub_kernel_image_size - GRUB_KERNEL_MACHINE_RAW_SIZE)
 267     + grub_total_module_size;
 268 }
 269
 270 /* Return the size of the memdisk image.  */
 271 grub_off_t
 272 grub_arch_memdisk_size (void)
 273 {
 274   return grub_memdisk_image_size;
 275 }