blob: d2b49d2365e76d962db243aca29735d85d564dfb [file] [log] [blame]
Adrian Bunk88278ca2008-05-19 16:53:02 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * bootstr.c: Boot string/argument acquisition from the PROM.
3 *
4 * Copyright(C) 1995 David S. Miller (davem@caip.rutgers.edu)
5 */
6
7#include <linux/string.h>
8#include <asm/oplib.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07009#include <linux/init.h>
10
11#define BARG_LEN 256
12static char barg_buf[BARG_LEN] = { 0 };
13static char fetched __initdata = 0;
14
Linus Torvalds1da177e2005-04-16 15:20:36 -070015char * __init
16prom_getbootargs(void)
17{
18 int iter;
19 char *cp, *arg;
20
21 /* This check saves us from a panic when bootfd patches args. */
22 if (fetched) {
23 return barg_buf;
24 }
25
Chen Gang242ece22013-05-30 11:35:22 +080026 switch (prom_vers) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070027 case PROM_V0:
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 cp = barg_buf;
29 /* Start from 1 and go over fd(0,0,0)kernel */
Chen Gang242ece22013-05-30 11:35:22 +080030 for (iter = 1; iter < 8; iter++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 arg = (*(romvec->pv_v0bootargs))->argv[iter];
Sam Ravnborg5f66dd32011-01-03 08:27:55 +000032 if (arg == NULL)
33 break;
Chen Gang242ece22013-05-30 11:35:22 +080034 while (*arg != 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070035 /* Leave place for space and null. */
Chen Gang242ece22013-05-30 11:35:22 +080036 if (cp >= barg_buf + BARG_LEN - 2)
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 /* We might issue a warning here. */
38 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039 *cp++ = *arg++;
40 }
41 *cp++ = ' ';
Chen Gang242ece22013-05-30 11:35:22 +080042 if (cp >= barg_buf + BARG_LEN - 1)
43 /* We might issue a warning here. */
44 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -070045 }
46 *cp = 0;
47 break;
48 case PROM_V2:
49 case PROM_V3:
50 /*
51 * V3 PROM cannot supply as with more than 128 bytes
52 * of an argument. But a smart bootstrap loader can.
53 */
54 strlcpy(barg_buf, *romvec->pv_v2bootargs.bootargs, sizeof(barg_buf));
55 break;
56 default:
57 break;
58 }
59
60 fetched = 1;
61 return barg_buf;
62}