3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 * See file CREDITS for list of people who contributed to this
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.
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.
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
30 #include <environment.h>
31 #include <asm/byteorder.h>
32 #ifdef CONFIG_SHOW_BOOT_PROGRESS
33 # include <status_led.h>
36 DECLARE_GLOBAL_DATA_PTR;
40 #define LINUX_MAX_ENVS 256
41 #define LINUX_MAX_ARGS 256
43 static ulong get_sp (void);
44 static void set_clocks_in_mhz (bd_t *kbd);
45 extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
47 void do_bootm_linux(cmd_tbl_t * cmdtp, int flag,
48 int argc, char *argv[],
49 bootm_headers_t *images, int verify)
51 ulong sp, sp_limit, alloc_current;
53 ulong rd_data_start, rd_data_end, rd_len;
54 ulong initrd_start, initrd_end;
56 ulong cmd_start, cmd_end;
59 void (*kernel) (bd_t *, ulong, ulong, ulong, ulong);
62 * Booting a (Linux) kernel image
64 * Allocate space for command line and board info - the
65 * address should be as high as possible within the reach of
66 * the kernel (see CFG_BOOTMAPSZ settings), but in unused
67 * memory, which means far enough below the current stack
71 debug ("## Current stack ends at 0x%08lx ", sp);
73 alloc_current = sp_limit = get_boot_sp_limit(sp);
74 debug ("=> set upper limit to 0x%08lx\n", sp_limit);
76 /* allocate space and init command line */
77 alloc_current = get_boot_cmdline (alloc_current, &cmd_start, &cmd_end);
79 /* allocate space for kernel copy of board info */
80 alloc_current = get_boot_kbd (alloc_current, &kbd);
81 set_clocks_in_mhz(kbd);
83 /* find kernel entry point */
84 if (images->legacy_hdr_valid) {
85 ep = image_get_ep (images->legacy_hdr_os);
86 #if defined(CONFIG_FIT)
87 } else if (images->fit_uname_os) {
88 fit_unsupported_reset ("M68K linux bootm");
89 do_reset (cmdtp, flag, argc, argv);
92 puts ("Could not find kernel entry point!\n");
93 do_reset (cmdtp, flag, argc, argv);
95 kernel = (void (*)(bd_t *, ulong, ulong, ulong, ulong))ep;
98 get_ramdisk (cmdtp, flag, argc, argv, images, verify,
99 IH_ARCH_M68K, &rd_data_start, &rd_data_end);
101 rd_len = rd_data_end - rd_data_start;
102 alloc_current = ramdisk_high (alloc_current, rd_data_start, rd_len,
103 kbd, sp_limit, get_sp (),
104 &initrd_start, &initrd_end);
106 debug("## Transferring control to Linux (at address %08lx) ...\n",
109 show_boot_progress (15);
112 * Linux Kernel Parameters (passing board info data):
113 * r3: ptr to board info data
114 * r4: initrd_start or 0 if no initrd
115 * r5: initrd_end - unused if r4 is 0
116 * r6: Start of command line string
117 * r7: End of command line string
119 (*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);
120 /* does not return */
123 static ulong get_sp (void)
127 asm("movel %%a7, %%d0\n"
128 "movel %%d0, %0\n": "=d"(sp): :"%d0");
133 static void set_clocks_in_mhz (bd_t *kbd)
137 if ((s = getenv("clocks_in_mhz")) != NULL) {
138 /* convert all clock information to MHz */
139 kbd->bi_intfreq /= 1000000L;
140 kbd->bi_busfreq /= 1000000L;