cmdline.c

  1/*
  2 * This file is subject to the terms and conditions of the GNU General Public
  3 * License.  See the file "COPYING" in the main directory of this archive
  4 * for more details.
  5 *
  6 * cmdline.c: Kernel command line creation using ARCS argc/argv.
  7 *
  8 * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
  9 */
 10#include <linux/bug.h>
 11#include <linux/init.h>
 12#include <linux/kernel.h>
 13#include <linux/string.h>
 14
 15#include <asm/sgialib.h>
 16#include <asm/bootinfo.h>
 17
 18#undef DEBUG_CMDLINE
 19
 20/*
 21 * A 32-bit ARC PROM pass arguments and environment as 32-bit pointer.
 22 * These macro take care of sign extension.
 23 */
 24#define prom_argv(index) ((char *) (long)argv[(index)])
 25
 26static char *ignored[] = {
 27	"ConsoleIn=",
 28	"ConsoleOut=",
 29	"SystemPartition=",
 30	"OSLoader=",
 31	"OSLoadPartition=",
 32	"OSLoadFilename=",
 33	"OSLoadOptions="
 34};
 35
 36static char *used_arc[][2] = {
 37	{ "OSLoadPartition=", "root=" },
 38	{ "OSLoadOptions=", "" }
 39};
 40
 41static char __init *move_firmware_args(int argc, LONG *argv, char *cp)
 42{
 43	char *s;
 44	int actr, i;
 45	size_t len;
 46
 47	actr = 1; /* Always ignore argv[0] */
 48
 49	while (actr < argc) {
 50		for (i = 0; i < ARRAY_SIZE(used_arc); i++) {
 51			len = strlen(used_arc[i][0]);
 52
 53			if (!strncmp(prom_argv(actr), used_arc[i][0], len)) {
 54			/* Ok, we want it. First append the replacement... */
 55				strcat(cp, used_arc[i][1]);
 56				cp += strlen(used_arc[i][1]);
 57				/* ... and now the argument */
 58				s = strchr(prom_argv(actr), '=');
 59				if (s) {
 60					s++;
 61					len = strlen(s);
 62					memcpy(cp, s, len + 1);
 63					cp += len;
 64				}
 65				*cp++ = ' ';
 66				break;
 67			}
 68		}
 69		actr++;
 70	}
 71
 72	return cp;
 73}
 74
 75void __init prom_init_cmdline(int argc, LONG *argv)
 76{
 77	char *cp;
 78	int actr, i;
 79	size_t len;
 80
 81	actr = 1; /* Always ignore argv[0] */
 82
 83	cp = arcs_cmdline;
 84	/*
 85	 * Move ARC variables to the beginning to make sure they can be
 86	 * overridden by later arguments.
 87	 */
 88	cp = move_firmware_args(argc, argv, cp);
 89
 90	while (actr < argc) {
 91		for (i = 0; i < ARRAY_SIZE(ignored); i++) {
 92			len = strlen(ignored[i]);
 93			if (!strncmp(prom_argv(actr), ignored[i], len))
 94				goto pic_cont;
 95		}
 96
 97		/* Ok, we want it. */
 98		len = strlen(prom_argv(actr));
 99		memcpy(cp, prom_argv(actr), len + 1);
100		cp += len;
101		*cp++ = ' ';
102
103	pic_cont:
104		actr++;
105	}
106
107	if (cp != arcs_cmdline)		/* get rid of trailing space */
108		--cp;
109	*cp = '\0';
110
111#ifdef DEBUG_CMDLINE
112	pr_debug("prom cmdline: %s\n", arcs_cmdline);
113#endif
114}