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         
debug("## Current stack ends at 0x%08lX ", sp);
  96
  97         sp -= 2048;             /* just to be sure */
  98         if (sp > CFG_BOOTMAPSZ)
  99                 sp = CFG_BOOTMAPSZ;
 100         sp &= ~0xF;
 101
 102         debug("=> set upper limit to 0x%08lX\n", sp);
 103
 104         cmdline = (char *)((sp - CFG_BARGSIZE) & ~0xF);
 105         kbd = (bd_t *) (((ulong) cmdline - sizeof(bd_t)) & ~0xF);
 106
 107         if ((s = getenv("bootargs")) == NULL)
 108                 s = "";
 109
 110         strcpy(cmdline, s);
 111
 112         cmd_start = (ulong) & cmdline[0];
 113         cmd_end = cmd_start + strlen(cmdline);
 114
 115         *kbd = *(gd->bd);
 116
 117 #ifdef  DEBUG
 118         printf("## cmdline at 0x%08lX ... 0x%08lX\n", cmd_start, cmd_end);
 119
 120         do_bdinfo(NULL, 0, 0, NULL);
 121 #endif
 122
 123         if ((s = getenv("clocks_in_mhz")) != NULL) {
 124                 /* convert all clock information to MHz */
 125                 kbd->bi_intfreq /= 1000000L;
 126                 kbd->bi_busfreq /= 1000000L;
 127         }
 128
 129         kernel =
 130             (void (*)(bd_t *, ulong, ulong, ulong, ulong))ntohl(hdr->ih_ep);
 131
 132         /*
 133          * Check if there is an initrd image
 134          */
 135
 136         if (argc >= 3) {
 137                 debug("Not skipping initrd\n");
 138                 SHOW_BOOT_PROGRESS(9);
 139
 140                 addr = simple_strtoul(argv[2], NULL, 16);
 141
 142                 printf("## Loading RAMDisk Image at %08lx ...\n", addr);
 143
 144                 /* Copy header so we can blank CRC field for re-calculation */
 145                 memmove(&header, (char *)addr, sizeof(image_header_t));
 146
 147                 if (ntohl(hdr->ih_magic) != IH_MAGIC) {
 148                         puts("Bad Magic Number\n");
 149                         SHOW_BOOT_PROGRESS(-10);
 150                         do_reset(cmdtp, flag, argc, argv);
 151                 }
 152
 153                 data = (ulong) & header;
 154                 len = sizeof(image_header_t);
 155
 156                 checksum = ntohl(hdr->ih_hcrc);
 157                 hdr->ih_hcrc = 0;
 158
 159                 if (crc32(0, (uchar *) data, len) != checksum) {
 160                         puts("Bad Header Checksum\n");
 161                         SHOW_BOOT_PROGRESS(-11);
 162                         do_reset(cmdtp, flag, argc, argv);
 163                 }
 164
 165                 SHOW_BOOT_PROGRESS(10);
 166
 167                 print_image_hdr(hdr);
 168
 169                 data = addr + sizeof(image_header_t);
 170                 len = ntohl(hdr->ih_size);
 171
 172                 if (verify) {
 173                         ulong csum = 0;
 174 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
 175                         ulong cdata = data, edata = cdata + len;
 176 #endif                          /* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
 177
 178                         puts("   Verifying Checksum ... ");
 179
 180 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
 181
 182                         while (cdata < edata) {
 183                                 ulong chunk = edata - cdata;
 184
 185                                 if (chunk > CHUNKSZ)
 186                                         chunk = CHUNKSZ;
 187                                 csum = crc32(csum, (uchar *) cdata, chunk);
 188                                 cdata += chunk;
 189
 190                                 WATCHDOG_RESET();
 191                         }
 192 #else                           /* !(CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG) */
 193                         csum = crc32(0, (uchar *) data, len);
 194 #endif                          /* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
 195
 196                         if (csum != ntohl(hdr->ih_dcrc)) {
 197                                 puts("Bad Data CRC\n");
 198                                 SHOW_BOOT_PROGRESS(-12);
 199                                 do_reset(cmdtp, flag, argc, argv);
 200                         }
 201                         puts("OK\n");
 202                 }
 203
 204                 SHOW_BOOT_PROGRESS(11);
 205
 206                 if ((hdr->ih_os != IH_OS_LINUX) ||
 207                     (hdr->ih_arch != IH_CPU_M68K) ||
 208                     (hdr->ih_type != IH_TYPE_RAMDISK)) {
 209                         puts("No Linux ColdFire Ramdisk Image\n");
 210                         SHOW_BOOT_PROGRESS(-13);
 211                         do_reset(cmdtp, flag, argc, argv);
 212                 }
 213
 214                 /*
 215                  * Now check if we have a multifile image
 216                  */
 217         } else if ((hdr->ih_type == IH_TYPE_MULTI) && (len_ptr[1])) {
 218                 u_long tail = ntohl(len_ptr[0]) % 4;
 219                 int i;
 220
 221                 SHOW_BOOT_PROGRESS(13);
 222
 223                 /* skip kernel length and terminator */
 224                 data = (ulong) (&len_ptr[2]);
 225                 /* skip any additional image length fields */
 226                 for (i = 1; len_ptr[i]; ++i)
 227                         data += 4;
 228                 /* add kernel length, and align */
 229                 data += ntohl(len_ptr[0]);
 230                 if (tail) {
 231                         data += 4 - tail;
 232                 }
 233
 234                 len = ntohl(len_ptr[1]);
 235
 236         } else {
 237                 /*
 238                  * no initrd image
 239                  */
 240                 SHOW_BOOT_PROGRESS(14);
 241
 242                 len = data = 0;
 243         }
 244
 245         if (!data) {
 246                 debug("No initrd\n");
 247         }
 248
 249         if (data) {
 250                 if (!initrd_copy_to_ram) {      /* zero-copy ramdisk support */
 251                         initrd_start = data;
 252                         initrd_end = initrd_start + len;
 253                 } else {
 254                         initrd_start = (ulong) kbd - len;
 255                         initrd_start &= ~(4096 - 1);    /* align on page */
 256
 257                         if (initrd_high) {
 258                                 ulong nsp;
 259
 260                                 /*
 261                                  * the inital ramdisk does not need to be within
 262                                  * CFG_BOOTMAPSZ as it is not accessed until after
 263                                  * the mm system is initialised.
 264                                  *
 265                                  * do the stack bottom calculation again and see if
 266                                  * the initrd will fit just below the monitor stack
 267                                  * bottom without overwriting the area allocated
 268                                  * above for command line args and board info.
 269                                  */
 270                                 asm("movel %%a7, %%d0\n"
 271                                     "movel %%d0, %0\n": "=d"(nsp): :"%d0");
 272                                 
                               nsp -= 2048;    /* just to be sure */
 273                                 nsp &= ~0xF;
 274
 275                                 if (nsp > initrd_high)  /* limit as specified */
 276                                         nsp = initrd_high;
 277
 278                                         nsp -= len;
 279                                 nsp &= ~(4096 - 1);     /* align on page */
 280
 281                                 if (nsp >= sp)
 282                                         initrd_start = nsp;
 283                         }
 284
 285                         SHOW_BOOT_PROGRESS(12);
 286
 287                         debug
 288                             ("## initrd at 0x%08lX ... 0x%08lX (len=%ld=0x%lX)\n",
 289                              data, data + len - 1, len, len);
 290
 291                         initrd_end = initrd_start + len;
 292                         printf("   Loading Ramdisk to %08lx, end %08lx ... ",
 293                                initrd_start, initrd_end);
 294 #if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
 295                         {
 296                                 size_t l = len;
 297                                 void *to = (void *)initrd_start;
 298                                 void *from = (void *)data;
 299
 300                                 while (l > 0) {
 301                                         size_t tail =
 302                                             (l > CHUNKSZ) ? CHUNKSZ : l;
 303                                         WATCHDOG_RESET();
 304                                         memmove(to, from, tail);
 305                                         to += tail;
 306                                         from += tail;
 307                                         l -= tail;
 308                                 }
 309                         }
 310 #else                           /* !(CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG) */
 311                         memmove((void *)initrd_start, (void *)data, len);
 312 #endif                          /* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
 313                         puts("OK\n");
 314                 }
 315         } else {
 316                 initrd_start = 0;
 317                 initrd_end = 0;
 318         }
 319
 320         debug("## Transferring control to Linux (at address %08lx) ...\n",
 321               (ulong) kernel);
 322
 323         SHOW_BOOT_PROGRESS(15);
 324
 325         /*
 326          * Linux Kernel Parameters (passing board info data):
 327          *   r3: ptr to board info data
 328          *   r4: initrd_start or 0 if no initrd
 329          *   r5: initrd_end - unused if r4 is 0
 330          *   r6: Start of command line string
 331          *   r7: End   of command line string
 332          */
 333         (*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);
 334         /* does not return */
 335 }