xref: /openbmc/linux/arch/mips/fw/lib/cmdline.c (revision b4e18b29)
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 #ifndef CONFIG_HAVE_PLAT_FW_INIT_CMDLINE
20 void __init fw_init_cmdline(void)
21 {
22 	int i;
23 
24 	/* Validate command line parameters. */
25 	if ((fw_arg0 >= CKSEG0) || (fw_arg1 < CKSEG0)) {
26 		fw_argc = 0;
27 		_fw_argv = NULL;
28 	} else {
29 		fw_argc = (fw_arg0 & 0x0000ffff);
30 		_fw_argv = (int *)fw_arg1;
31 	}
32 
33 	/* Validate environment pointer. */
34 	if (fw_arg2 < CKSEG0)
35 		_fw_envp = NULL;
36 	else
37 		_fw_envp = (int *)fw_arg2;
38 
39 	for (i = 1; i < fw_argc; i++) {
40 		strlcat(arcs_cmdline, fw_argv(i), COMMAND_LINE_SIZE);
41 		if (i < (fw_argc - 1))
42 			strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
43 	}
44 }
45 #endif
46 
47 char * __init fw_getcmdline(void)
48 {
49 	return &(arcs_cmdline[0]);
50 }
51 
52 char *fw_getenv(char *envname)
53 {
54 	char *result = NULL;
55 
56 	if (_fw_envp != NULL) {
57 		/*
58 		 * Return a pointer to the given environment variable.
59 		 * YAMON uses "name", "value" pairs, while U-Boot uses
60 		 * "name=value".
61 		 */
62 		int i, yamon, index = 0;
63 
64 		yamon = (strchr(fw_envp(index), '=') == NULL);
65 		i = strlen(envname);
66 
67 		while (fw_envp(index)) {
68 			if (strncmp(envname, fw_envp(index), i) == 0) {
69 				if (yamon) {
70 					result = fw_envp(index + 1);
71 					break;
72 				} else if (fw_envp(index)[i] == '=') {
73 					result = fw_envp(index) + i + 1;
74 					break;
75 				}
76 			}
77 
78 			/* Increment array index. */
79 			if (yamon)
80 				index += 2;
81 			else
82 				index += 1;
83 		}
84 	}
85 
86 	return result;
87 }
88 
89 unsigned long fw_getenvl(char *envname)
90 {
91 	unsigned long envl = 0UL;
92 	char *str;
93 	int tmp;
94 
95 	str = fw_getenv(envname);
96 	if (str) {
97 		tmp = kstrtoul(str, 0, &envl);
98 		if (tmp)
99 			envl = 0;
100 	}
101 
102 	return envl;
103 }
104