prom.c

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/*
 *
 * BRIEF MODULE DESCRIPTION
 *    PROM library initialisation code, supports YAMON and U-Boot.
 *
 * Copyright 2000-2001, 2006, 2008 MontaVista Software Inc.
 * Author: MontaVista Software, Inc. <[email protected]>
 *
 * This file was derived from Carsten Langgaard's
 * arch/mips/mips-boards/xx files.
 *
 * Carsten Langgaard, [email protected]
 * Copyright (C) 1999,2000 MIPS Technologies, Inc.  All rights reserved.
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 *
 *  THIS  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
 *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
 *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *  You should have received a copy of the  GNU General Public License along
 *  with this program; if not, write  to the Free Software Foundation, Inc.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/string.h>

#include <asm/bootinfo.h>

int prom_argc;
char **prom_argv;
char **prom_envp;

void __init prom_init_cmdline(void)
{
    int i;

    for (i = 1; i < prom_argc; i++) {
        strlcat(arcs_cmdline, prom_argv[i], COMMAND_LINE_SIZE);
        if (i < (prom_argc - 1))
            strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
    }
}

char *prom_getenv(char *envname)
{
    /*
     * Return a pointer to the given environment variable.
     * YAMON uses "name", "value" pairs, while U-Boot uses "name=value".
     */

    char **env = prom_envp;
    int i = strlen(envname);
    int yamon = (*env && strchr(*env, '=') == NULL);

    while (*env) {
        if (yamon) {
            if (strcmp(envname, *env++) == 0)
                return *env;
        } else if (strncmp(envname, *env, i) == 0 && (*env)[i] == '=')
            return *env + i + 1;
        env++;
    }

    return NULL;
}

static inline unsigned char str2hexnum(unsigned char c)
{
    if (c >= '0' && c <= '9')
        return c - '0';
    if (c >= 'a' && c <= 'f')
        return c - 'a' + 10;
    if (c >= 'A' && c <= 'F')
        return c - 'A' + 10;

    return 0; /* foo */
}

static inline void str2eaddr(unsigned char *ea, unsigned char *str)
{
    int i;

    for (i = 0; i < 6; i++) {
        unsigned char num;

        if ((*str == '.') || (*str == ':'))
            str++;
        num  = str2hexnum(*str++) << 4;
        num |= str2hexnum(*str++);
        ea[i] = num;
    }
}

int __init prom_get_ethernet_addr(char *ethernet_addr)
{
    char *ethaddr_str;

    /* Check the environment variables first */
    ethaddr_str = prom_getenv("ethaddr");
    if (!ethaddr_str) {
        /* Check command line */
        ethaddr_str = strstr(arcs_cmdline, "ethaddr=");
        if (!ethaddr_str)
            return -1;

        ethaddr_str += strlen("ethaddr=");
    }

    str2eaddr(ethernet_addr, ethaddr_str);

    return 0;
}

void __init prom_free_prom_memory(void)
{
}