release/src-rt-6.x.4708/linux/linux-2.6.36/arch/mips/alchemy/common/prom.c

   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 __init 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 __init 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
 127 void __init prom_free_prom_memory(void)
 128 {
 129 }