original_kernel/arch/mips/loongson/common/env.c

79 lines
2.1 KiB
C

/*
* Based on Ocelot Linux port, which is
* Copyright 2001 MontaVista Software Inc.
* Author: jsun@mvista.com or jsun@junsun.net
*
* Copyright 2003 ICT CAS
* Author: Michael Guo <guoyi@ict.ac.cn>
*
* Copyright (C) 2007 Lemote Inc. & Insititute of Computing Technology
* Author: Fuxin Zhang, zhangfx@lemote.com
*
* Copyright (C) 2009 Lemote Inc. & Insititute of Computing Technology
* Author: Wu Zhangjin, wuzj@lemote.com
*
* 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.
*/
#include <linux/module.h>
#include <asm/bootinfo.h>
#include <loongson.h>
unsigned long cpu_clock_freq;
EXPORT_SYMBOL(cpu_clock_freq);
unsigned long memsize, highmemsize;
#define parse_even_earlier(res, option, p) \
do { \
if (strncmp(option, (char *)p, strlen(option)) == 0) \
strict_strtol((char *)p + strlen(option"="), \
10, &res); \
} while (0)
void __init prom_init_env(void)
{
/* pmon passes arguments in 32bit pointers */
int *_prom_envp;
unsigned long bus_clock;
unsigned int processor_id;
long l;
/* firmware arguments are initialized in head.S */
_prom_envp = (int *)fw_arg2;
l = (long)*_prom_envp;
while (l != 0) {
parse_even_earlier(bus_clock, "busclock", l);
parse_even_earlier(cpu_clock_freq, "cpuclock", l);
parse_even_earlier(memsize, "memsize", l);
parse_even_earlier(highmemsize, "highmemsize", l);
_prom_envp++;
l = (long)*_prom_envp;
}
if (memsize == 0)
memsize = 256;
if (bus_clock == 0)
bus_clock = 66000000;
if (cpu_clock_freq == 0) {
processor_id = (&current_cpu_data)->processor_id;
switch (processor_id & PRID_REV_MASK) {
case PRID_REV_LOONGSON2E:
cpu_clock_freq = 533080000;
break;
case PRID_REV_LOONGSON2F:
cpu_clock_freq = 797000000;
break;
default:
cpu_clock_freq = 100000000;
break;
}
}
pr_info("busclock=%ld, cpuclock=%ld, memsize=%ld, highmemsize=%ld\n",
bus_clock, cpu_clock_freq, memsize, highmemsize);
}