xref: /openbmc/linux/arch/mips/fw/lib/cmdline.c (revision a06c488d)
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  * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
7  */
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/string.h>
11 
12 #include <asm/addrspace.h>
13 #include <asm/fw/fw.h>
14 
15 int fw_argc;
16 int *_fw_argv;
17 int *_fw_envp;
18 
19 void __init fw_init_cmdline(void)
20 {
21 	int i;
22 
23 	/* Validate command line parameters. */
24 	if ((fw_arg0 >= CKSEG0) || (fw_arg1 < CKSEG0)) {
25 		fw_argc = 0;
26 		_fw_argv = NULL;
27 	} else {
28 		fw_argc = (fw_arg0 & 0x0000ffff);
29 		_fw_argv = (int *)fw_arg1;
30 	}
31 
32 	/* Validate environment pointer. */
33 	if (fw_arg2 < CKSEG0)
34 		_fw_envp = NULL;
35 	else
36 		_fw_envp = (int *)fw_arg2;
37 
38 	for (i = 1; i < fw_argc; i++) {
39 		strlcat(arcs_cmdline, fw_argv(i), COMMAND_LINE_SIZE);
40 		if (i < (fw_argc - 1))
41 			strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
42 	}
43 }
44 
45 char * __init fw_getcmdline(void)
46 {
47 	return &(arcs_cmdline[0]);
48 }
49 
50 char *fw_getenv(char *envname)
51 {
52 	char *result = NULL;
53 
54 	if (_fw_envp != NULL) {
55 		/*
56 		 * Return a pointer to the given environment variable.
57 		 * YAMON uses "name", "value" pairs, while U-Boot uses
58 		 * "name=value".
59 		 */
60 		int i, yamon, index = 0;
61 
62 		yamon = (strchr(fw_envp(index), '=') == NULL);
63 		i = strlen(envname);
64 
65 		while (fw_envp(index)) {
66 			if (strncmp(envname, fw_envp(index), i) == 0) {
67 				if (yamon) {
68 					result = fw_envp(index + 1);
69 					break;
70 				} else if (fw_envp(index)[i] == '=') {
71 					result = fw_envp(index) + i + 1;
72 					break;
73 				}
74 			}
75 
76 			/* Increment array index. */
77 			if (yamon)
78 				index += 2;
79 			else
80 				index += 1;
81 		}
82 	}
83 
84 	return result;
85 }
86 
87 unsigned long fw_getenvl(char *envname)
88 {
89 	unsigned long envl = 0UL;
90 	char *str;
91 	int tmp;
92 
93 	str = fw_getenv(envname);
94 	if (str) {
95 		tmp = kstrtoul(str, 0, &envl);
96 		if (tmp)
97 			envl = 0;
98 	}
99 
100 	return envl;
101 }
102