xref: /openbmc/u-boot/arch/x86/lib/cmd_boot.c (revision 983c72f4)
1 /*
2  * (C) Copyright 2008-2011
3  * Graeme Russ, <graeme.russ@gmail.com>
4  *
5  * (C) Copyright 2002
6  * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
7  *
8  * (C) Copyright 2002
9  * Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
10  *
11  * (C) Copyright 2002
12  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
13  * Marius Groeger <mgroeger@sysgo.de>
14  *
15  * See file CREDITS for list of people who contributed to this
16  * project.
17  *
18  * This program is free software; you can redistribute it and/or
19  * modify it under the terms of the GNU General Public License as
20  * published by the Free Software Foundation; either version 2 of
21  * the License, or (at your option) any later version.
22  *
23  * This program is distributed in the hope that it will be useful,
24  * but WITHOUT ANY WARRANTY; without even the implied warranty of
25  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
26  * GNU General Public License for more details.
27  *
28  * You should have received a copy of the GNU General Public License
29  * along with this program; if not, write to the Free Software
30  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
31  * MA 02111-1307 USA
32  */
33 
34 #include <common.h>
35 #include <command.h>
36 #include <malloc.h>
37 #include <asm/u-boot-x86.h>
38 
39 DECLARE_GLOBAL_DATA_PTR;
40 
41 unsigned long do_go_exec(ulong (*entry)(int, char * const []),
42 			 int argc, char * const argv[])
43 {
44 	unsigned long ret = 0;
45 	char **argv_tmp;
46 
47 	/*
48 	 * x86 does not use a dedicated register to pass the pointer to
49 	 * the global_data, so it is instead passed as argv[-1]. By using
50 	 * argv[-1], the called 'Application' can use the contents of
51 	 * argv natively. However, to safely use argv[-1] a new copy of
52 	 * argv is needed with the extra element
53 	 */
54 	argv_tmp = malloc(sizeof(char *) * (argc + 1));
55 
56 	if (argv_tmp) {
57 		argv_tmp[0] = (char *)gd;
58 
59 		memcpy(&argv_tmp[1], argv, (size_t)(sizeof(char *) * argc));
60 
61 		ret = (entry) (argc, &argv_tmp[1]);
62 		free(argv_tmp);
63 	}
64 
65 	return ret;
66 }
67