lib_m68k/bootm.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 <watchdog.h>
  30 #include <environment.h>
  31 #include <asm/byteorder.h>
  32 #ifdef CONFIG_SHOW_BOOT_PROGRESS
  33 # include <status_led.h>
  34 #endif
  35
  36 DECLARE_GLOBAL_DATA_PTR;
  37
  38 extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
  39
  40 #define PHYSADDR(x) x
  41
  42 #define LINUX_MAX_ENVS          256
  43 #define LINUX_MAX_ARGS          256
  44
  45 static ulong get_sp (void);
  46 static void set_clocks_in_mhz (bd_t *kbd);
  47 extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
  48
  49 void do_bootm_linux(cmd_tbl_t * cmdtp, int flag,
  50                     int argc, char *argv[],
  51                     bootm_headers_t *images)
  52 {
  53         ulong sp;
  54
  55         ulong rd_data_start, rd_data_end, rd_len;
  56         ulong initrd_start, initrd_end;
  57         int ret;
  58
  59         ulong cmd_start, cmd_end;
  60         ulong bootmap_base = 0;
  61         bd_t  *kbd;
  62         ulong ep = 0;
  63         void  (*kernel) (bd_t *, ulong, ulong, ulong, ulong);
  64         struct lmb *lmb = images->lmb;
  65
  66         /*
  67          * Booting a (Linux) kernel image
  68          *
  69          * Allocate space for command line and board info - the
  70          * address should be as high as possible within the reach of
  71          * the kernel (see CFG_BOOTMAPSZ settings), but in unused
  72          * memory, which means far enough below the current stack
  73          * pointer.
  74          */
  75         sp = get_sp();
  76         debug ("## Current stack ends at 0x%08lx ", sp);
  77
  78         /* adjust sp by 1K to be safe */
  79         sp -= 1024;
  80         lmb_reserve(lmb, sp, (CFG_SDRAM_BASE + gd->ram_size - sp));
  81
  82         /* allocate space and init command line */
  83         ret = get_boot_cmdline (lmb, &cmd_start, &cmd_end, bootmap_base);
  84         if (ret) {
  85                 puts("ERROR with allocation of cmdline\n");
  86                 goto error;
  87         }
  88
  89         /* allocate space for kernel copy of board info */
  90         ret = get_boot_kbd (lmb, &kbd, bootmap_base);
  91         if (ret) {
  92                 puts("ERROR with allocation of kernel bd\n");
  93                 goto error;
  94         }
  95         set_clocks_in_mhz(kbd);
  96
  97         /* find kernel entry point */
  98         if (images->legacy_hdr_valid) {
  99                 ep = image_get_ep (images->legacy_hdr_os);
 100 #if defined(CONFIG_FIT)
 101         } else if (images->fit_uname_os) {
 102                 fit_unsupported_reset ("M68K linux bootm");
 103                 do_reset (cmdtp, flag, argc, argv);
 104 #endif
 105         } else {
 106                 puts ("Could not find kernel entry point!\n");
 107                 do_reset (cmdtp, flag, argc, argv);
 108         }
 109         kernel = (void (*)(bd_t *, ulong, ulong, ulong, ulong))ep;
 110
 111         /* find ramdisk */
 112         ret = get_ramdisk (cmdtp, flag, argc, argv, images,
 113                         IH_ARCH_M68K, &rd_data_start, &rd_data_end);
 114
 115         if (ret)
 116                 goto error;
 117
 118         rd_len = rd_data_end - rd_data_start;
 119         ret = ramdisk_high (lmb, rd_data_start, rd_len, &initrd_start, &initrd_end);
 120         if (ret)
 121                 goto error;
 122
 123         debug("## Transferring control to Linux (at address %08lx) ...\n",
 124               (ulong) kernel);
 125
 126         show_boot_progress (15);
 127
 128         /*
 129          * Linux Kernel Parameters (passing board info data):
 130          *   r3: ptr to board info data
 131          *   r4: initrd_start or 0 if no initrd
 132          *   r5: initrd_end - unused if r4 is 0
 133          *   r6: Start of command line string
 134          *   r7: End   of command line string
 135          */
 136         (*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);
 137         /* does not return */
 138         return ;
 139
 140 error:
 141         do_reset (cmdtp, flag, argc, argv);
 142         return ;
 143 }
 144
 145 static ulong get_sp (void)
 146 {
 147         ulong sp;
 148
 149         asm("movel %%a7, %%d0\n"
 150             "movel %%d0, %0\n": "=d"(sp): :"%d0");
 151
 152         return sp;
 153 }
 154
 155 static void set_clocks_in_mhz (bd_t *kbd)
 156 {
 157         char *s;
 158
 159         if ((s = getenv("clocks_in_mhz")) != NULL) {
 160                 /* convert all clock information to MHz */
 161                 kbd->bi_intfreq /= 1000000L;
 162                 kbd->bi_busfreq /= 1000000L;
 163         }
 164 }