xref: /linux/arch/mips/alchemy/common/prom.c (revision 47902f3611b392209e2a412bf7ec02dca95e666d)
1 /*
2  *
3  * BRIEF MODULE DESCRIPTION
4  *    PROM library initialisation code, supports YAMON and U-Boot.
5  *
6  * Copyright 2000-2001, 2006, 2008 MontaVista Software Inc.
7  * Author: MontaVista Software, Inc. <source@mvista.com>
8  *
9  * This file was derived from Carsten Langgaard's
10  * arch/mips/mips-boards/xx files.
11  *
12  * Carsten Langgaard, carstenl@mips.com
13  * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
14  *
15  *  This program is free software; you can redistribute  it and/or modify it
16  *  under  the terms of  the GNU General  Public License as published by the
17  *  Free Software Foundation;  either version 2 of the  License, or (at your
18  *  option) any later version.
19  *
20  *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
21  *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
22  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
23  *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
24  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
26  *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
27  *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
28  *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  *
31  *  You should have received a copy of the  GNU General Public License along
32  *  with this program; if not, write  to the Free Software Foundation, Inc.,
33  *  675 Mass Ave, Cambridge, MA 02139, USA.
34  */
35 
36 #include <linux/module.h>
37 #include <linux/init.h>
38 #include <linux/string.h>
39 
40 #include <asm/bootinfo.h>
41 
42 int prom_argc;
43 char **prom_argv;
44 char **prom_envp;
45 
46 void prom_init_cmdline(void)
47 {
48 	int i;
49 
50 	for (i = 1; i < prom_argc; i++) {
51 		strlcat(arcs_cmdline, prom_argv[i], COMMAND_LINE_SIZE);
52 		if (i < (prom_argc - 1))
53 			strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
54 	}
55 }
56 
57 char *prom_getenv(char *envname)
58 {
59 	/*
60 	 * Return a pointer to the given environment variable.
61 	 * YAMON uses "name", "value" pairs, while U-Boot uses "name=value".
62 	 */
63 
64 	char **env = prom_envp;
65 	int i = strlen(envname);
66 	int yamon = (*env && strchr(*env, '=') == NULL);
67 
68 	while (*env) {
69 		if (yamon) {
70 			if (strcmp(envname, *env++) == 0)
71 				return *env;
72 		} else if (strncmp(envname, *env, i) == 0 && (*env)[i] == '=')
73 			return *env + i + 1;
74 		env++;
75 	}
76 
77 	return NULL;
78 }
79 
80 static inline unsigned char str2hexnum(unsigned char c)
81 {
82 	if (c >= '0' && c <= '9')
83 		return c - '0';
84 	if (c >= 'a' && c <= 'f')
85 		return c - 'a' + 10;
86 	if (c >= 'A' && c <= 'F')
87 		return c - 'A' + 10;
88 
89 	return 0; /* foo */
90 }
91 
92 static inline void str2eaddr(unsigned char *ea, unsigned char *str)
93 {
94 	int i;
95 
96 	for (i = 0; i < 6; i++) {
97 		unsigned char num;
98 
99 		if ((*str == '.') || (*str == ':'))
100 			str++;
101 		num  = str2hexnum(*str++) << 4;
102 		num |= str2hexnum(*str++);
103 		ea[i] = num;
104 	}
105 }
106 
107 int prom_get_ethernet_addr(char *ethernet_addr)
108 {
109 	char *ethaddr_str;
110 
111 	/* Check the environment variables first */
112 	ethaddr_str = prom_getenv("ethaddr");
113 	if (!ethaddr_str) {
114 		/* Check command line */
115 		ethaddr_str = strstr(arcs_cmdline, "ethaddr=");
116 		if (!ethaddr_str)
117 			return -1;
118 
119 		ethaddr_str += strlen("ethaddr=");
120 	}
121 
122 	str2eaddr(ethernet_addr, ethaddr_str);
123 
124 	return 0;
125 }
126 EXPORT_SYMBOL(prom_get_ethernet_addr);
127 
128 void __init prom_free_prom_memory(void)
129 {
130 }
131