lib_m68k/m68k_linux.c

   1 /*
   2  * (C) Copyright 2003
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  *
  22  */
  23
  24 #include <common.h>
  25 #include <command.h>
  26 #include <image.h>
  27 #include <zlib.h>
  28 #include <bzlib.h>
  29 #include <environment.h>
  30 #include <asm/byteorder.h>
  31
  32 DECLARE_GLOBAL_DATA_PTR;
  33
  34 #define PHYSADDR(x) x
  35
  36 #define LINUX_MAX_ENVS          256
  37 #define LINUX_MAX_ARGS          256
  38
  39 #ifdef CONFIG_SHOW_BOOT_PROGRESS
  40 # include <status_led.h>
  41 # define SHOW_BOOT_PROGRESS(arg)        show_boot_progress(arg)
  42 #else
  43 # define SHOW_BOOT_PROGRESS(arg)
  44 #endif
  45
  46 extern image_header_t header;
  47
  48 void do_bootm_linux(cmd_tbl_t * cmdtp, int flag,
  49                     int argc, char *argv[],
  50                     ulong addr, ulong * len_ptr, int verify)
  51 {
  52         ulong sp;
  53         ulong len, checksum;
  54         ulong initrd_start, initrd_end;
  55         ulong cmd_start, cmd_end;
  56         ulong initrd_high;
  57         ulong data;
  58         int initrd_copy_to_ram = 1;
  59         char *cmdline;
  60         char *s;
  61         bd_t *kbd;
  62         void (*kernel) (bd_t *, ulong, ulong, ulong, ulong);
  63         image_header_t *hdr = &header;
  64
  65         if ((s = getenv("initrd_high")) != NULL) {
  66                 /* a value of "no" or a similar string will act like 0,
  67                  * turning the "load high" feature off. This is intentional.
  68                  */
  69                 initrd_high = simple_strtoul(s, NULL, 16);
  70                 if (initrd_high == ~0)
  71                         initrd_copy_to_ram = 0;
  72         } else {                /* not set, no restrictions to load high */
  73                 initrd_high = ~0;
  74         }
  75
  76 #ifdef CONFIG_LOGBUFFER
  77         kbd = gd->bd;
  78         /* Prevent initrd from overwriting logbuffer */
  79         if (initrd_high < (kbd->bi_memsize - LOGBUFF_LEN - LOGBUFF_OVERHEAD))
  80                 initrd_high = kbd->bi_memsize - LOGBUFF_LEN - LOGBUFF_OVERHEAD;
  81         debug("## Logbuffer at 0x%08lX ", kbd->bi_memsize - LOGBUFF_LEN);
  82 #endif
  83
  84         /*
  85          * Booting a (Linux) kernel image
  86          *
  87          * Allocate space for command line and board info - the
  88          * address should be as high as possible within the reach of
  89          * the kernel (see CFG_BOOTMAPSZ settings), but in unused
  90          * memory, which means far enough below the current stack
  91          * pointer.
  92          */
  93         asm("movel %%a7, %%d0\n"
  94             "movel %%d0, %0\n": "=d"(sp): :"%d0");
  95
  96         debug("## Current stack ends at 0x%08lX ", sp);
  97
  98         sp -= 2048;             /* just to be sure */
  99         if (sp > CFG_BOOTMAPSZ)
 100                 sp = CFG_BOOTMAPSZ;
 101         sp &= ~0xF;
 102
 103         debug("=> set upper limit to 0x%08lX\n", sp);
 104
 105         cmdline = (char *)((sp - CFG_BARGSIZE) & ~0xF);
 106         kbd = (bd_t *) (((ulong) cmdline - sizeof(bd_t)) & ~0xF);
 107
 108         if ((s = getenv("bootargs")) == NULL)
 109                 s = "";
 110
 111         strcpy(cmdline, s);
 112
 113         cmd_start = (ulong) & cmdline[0];
 114         cmd_end = cmd_start + strlen(cmdline);
 115
 116         *kbd = *(gd->bd);
 117
 118 #ifdef  DEBUG
 119         printf("## cmdline at 0x%08lX ... 0x%08lX\n", cmd_start, cmd_end);
 120
 121         do_bdinfo(NULL, 0, 0, NULL);
 122 #endif
 123
 124         if ((s = getenv("clocks_in_mhz")) != NULL) {
 125                 /* convert all clock information to MHz */
 126                 kbd->bi_intfreq /= 1000000L;
 127                 kbd->bi_busfreq /= 1000000L;
 128         }
 129
 130         kernel =
 131             (void (*)(bd_t *, ulong, ulong, ulong, ulong))ntohl(hdr->ih_ep);
 132
 133         /*
 134          * Check if there is an initrd image
 135          */
 136
 137         if (argc >= 3) {
 138                 debug("Not skipping initrd\n");
 139                 SHOW_BOOT_PROGRESS(9);
 140
 141                 addr = simple_strtoul(argv[2], NULL, 16);
 142
 143                 printf("## Loading RAMDisk Image at %08lx ...\n", addr);
 144
 145                 /* Copy header so we can blank CRC field for re-calculation */
 146                 memmove(&header, (char *)addr, sizeof(image_header_t));
 147
 148                 if (ntohl(hdr->ih_magic) != IH_MAGIC) {
 149                         puts("Bad Magic Number\n");
 150                         SHOW_BOOT_PROGRESS(-10);
 151                         do_reset(cmdtp, flag, argc, argv);
 152                 }
 153
 154                 data = (ulong) & header;
 155                 len = sizeof(image_header_t);
 156
 157                 checksum = ntohl(hdr->ih_hcrc);
 158                 hdr->ih_hcrc = 0;
 159
 160                 if (crc32(0, (uchar *) data, len) != checksum) {
 161                         puts("Bad Header Checksum\n");
 162                         SHOW_BOOT_PROGRESS(-11);
 163                         do_reset(cmdtp, flag, argc, argv);
 164                 }
 165
 166                 SHOW_BOOT_PROGRESS(10);
 167
 168                 print_image_hdr(hdr);
 169
 170                 data = addr + sizeof(image_header_t);
 171                 len = ntohl(hdr->ih_size);
 172
 173                 if (verify) {
 174                         ulong csum = 0;
 175 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
 176                         ulong cdata = data, edata = cdata + len;
 177 #endif                          /* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
 178
 179                         puts("   Verifying Checksum ... ");
 180
 181 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
 182
 183                         while (cdata < edata) {
 184                                 ulong chunk = edata - cdata;
 185
 186                                 if (chunk > CHUNKSZ)
 187                                         chunk = CHUNKSZ;
 188                                 csum = crc32(csum, (uchar *) cdata, chunk);
 189                                 cdata += chunk;
 190
 191                                 WATCHDOG_RESET();
 192                         }
 193 #else                           /* !(CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG) */
 194                         csum = crc32(0, (uchar *) data, len);
 195 #endif                          /* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
 196
 197                         if (csum != ntohl(hdr->ih_dcrc)) {
 198                                 puts("Bad Data CRC\n");
 199                                 SHOW_BOOT_PROGRESS(-12);
 200                                 do_reset(cmdtp, flag, argc, argv);
 201                         }
 202                         puts("OK\n");
 203                 }
 204
 205                 SHOW_BOOT_PROGRESS(11);
 206
 207                 if ((hdr->ih_os != IH_OS_LINUX) ||
 208                     (hdr->ih_arch != IH_CPU_M68K) ||
 209                     (hdr->ih_type != IH_TYPE_RAMDISK)) {
 210                         puts("No Linux ColdFire Ramdisk Image\n");
 211                         SHOW_BOOT_PROGRESS(-13);
 212                         do_reset(cmdtp, flag, argc, argv);
 213                 }
 214
 215                 /*
 216                  * Now check if we have a multifile image
 217                  */
 218         } else if ((hdr->ih_type == IH_TYPE_MULTI) && (len_ptr[1])) {
 219                 u_long tail = ntohl(len_ptr[0]) % 4;
 220                 int i;
 221
 222                 SHOW_BOOT_PROGRESS(13);
 223
 224                 /* skip kernel length and terminator */
 225                 data = (ulong) (&len_ptr[2]);
 226                 /* skip any additional image length fields */
 227                 for (i = 1; len_ptr[i]; ++i)
 228                         data += 4;
 229                 /* add kernel length, and align */
 230                 data += ntohl(len_ptr[0]);
 231                 if (tail) {
 232                         data += 4 - tail;
 233                 }
 234
 235                 len = ntohl(len_ptr[1]);
 236
 237         } else {
 238                 /*
 239                  * no initrd image
 240                  */
 241                 SHOW_BOOT_PROGRESS(14);
 242
 243                 len = data = 0;
 244         }
 245
 246         if (!data) {
 247                 debug("No initrd\n");
 248         }
 249
 250         if (data) {
 251                 if (!initrd_copy_to_ram) {      /* zero-copy ramdisk support */
 252                         initrd_start = data;
 253                         initrd_end = initrd_start + len;
 254                 } else {
 255                         initrd_start = (ulong) kbd - len;
 256                         initrd_start &= ~(4096 - 1);    /* align on page */
 257
 258                         if (initrd_high) {
 259                                 ulong nsp;
 260
 261                                 /*
 262                                  * the inital ramdisk does not need to be within
 263                                  * CFG_BOOTMAPSZ as it is not accessed until after
 264                                  * the mm system is initialised.
 265                                  *
 266                                  * do the stack bottom calculation again and see if
 267                                  * the initrd will fit just below the monitor stack
 268                                  * bottom without overwriting the area allocated
 269                                  * above for command line args and board info.
 270                                  */
 271                                 asm("movel %%a7, %%d0\n"
 272                                     "movel %%d0, %0\n": "=d"(nsp): :"%d0");
 273
 274                                 nsp -= 2048;    /* just to be sure */
 275                                 nsp &= ~0xF;
 276
 277                                 if (nsp > initrd_high)  /* limit as specified */
 278                                         nsp = initrd_high;
 279
 280                                         nsp -= len;
 281                                 nsp &= ~(4096 - 1);     /* align on page */
 282
 283                                 if (nsp >= sp)
 284                                         initrd_start = nsp;
 285                         }
 286
 287                         SHOW_BOOT_PROGRESS(12);
 288
 289                         debug
 290                             ("## initrd at 0x%08lX ... 0x%08lX (len=%ld=0x%lX)\n",
 291                              data, data + len - 1, len, len);
 292
 293                         initrd_end = initrd_start + len;
 294                         printf("   Loading Ramdisk to %08lx, end %08lx ... ",
 295                                initrd_start, initrd_end);
 296 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
 297                         {
 298                                 size_t l = len;
 299                                 void *to = (void *)initrd_start;
 300                                 void *from = (void *)data;
 301
 302                                 while (l > 0) {
 303                                         size_t tail =
 304                                             (l > CHUNKSZ) ? CHUNKSZ : l;
 305                                         WATCHDOG_RESET();
 306                                         memmove(to, from, tail);
 307                                         to += tail;
 308                                         from += tail;
 309                                         l -= tail;
 310                                 }
 311                         }
 312 #else                           /* !(CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG) */
 313                         memmove((void *)initrd_start, (void *)data, len);
 314 #endif                          /* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
 315                         puts("OK\n");
 316                 }
 317         } else {
 318                 initrd_start = 0;
 319                 initrd_end = 0;
 320         }
 321
 322         debug("## Transferring control to Linux (at address %08lx) ...\n",
 323               (ulong) kernel);
 324
 325         SHOW_BOOT_PROGRESS(15);
 326
 327         /*
 328          * Linux Kernel Parameters (passing board info data):
 329          *   r3: ptr to board info data
 330          *   r4: initrd_start or 0 if no initrd
 331          *   r5: initrd_end - unused if r4 is 0
 332          *   r6: Start of command line string
 333          *   r7: End   of command line string
 334          */
 335         (*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);
 336         /* does not return */
 337 }