MIPS: Loongson: Change the Email address of Wu Zhangjin
[kernel.git] / arch / mips / loongson / common / env.c
1 /*
2  * Based on Ocelot Linux port, which is
3  * Copyright 2001 MontaVista Software Inc.
4  * Author: jsun@mvista.com or jsun@junsun.net
5  *
6  * Copyright 2003 ICT CAS
7  * Author: Michael Guo <guoyi@ict.ac.cn>
8  *
9  * Copyright (C) 2007 Lemote Inc. & Insititute of Computing Technology
10  * Author: Fuxin Zhang, zhangfx@lemote.com
11  *
12  * Copyright (C) 2009 Lemote Inc.
13  * Author: Wu Zhangjin, wuzhangjin@gmail.com
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 #include <linux/module.h>
21
22 #include <asm/bootinfo.h>
23
24 #include <loongson.h>
25
26 unsigned long cpu_clock_freq;
27 EXPORT_SYMBOL(cpu_clock_freq);
28 unsigned long memsize, highmemsize;
29
30 #define parse_even_earlier(res, option, p)                              \
31 do {                                                                    \
32         if (strncmp(option, (char *)p, strlen(option)) == 0)            \
33                         strict_strtol((char *)p + strlen(option"="),    \
34                                         10, &res);                      \
35 } while (0)
36
37 void __init prom_init_env(void)
38 {
39         /* pmon passes arguments in 32bit pointers */
40         int *_prom_envp;
41         unsigned long bus_clock;
42         unsigned int processor_id;
43         long l;
44
45         /* firmware arguments are initialized in head.S */
46         _prom_envp = (int *)fw_arg2;
47
48         l = (long)*_prom_envp;
49         while (l != 0) {
50                 parse_even_earlier(bus_clock, "busclock", l);
51                 parse_even_earlier(cpu_clock_freq, "cpuclock", l);
52                 parse_even_earlier(memsize, "memsize", l);
53                 parse_even_earlier(highmemsize, "highmemsize", l);
54                 _prom_envp++;
55                 l = (long)*_prom_envp;
56         }
57         if (memsize == 0)
58                 memsize = 256;
59         if (bus_clock == 0)
60                 bus_clock = 66000000;
61         if (cpu_clock_freq == 0) {
62                 processor_id = (&current_cpu_data)->processor_id;
63                 switch (processor_id & PRID_REV_MASK) {
64                 case PRID_REV_LOONGSON2E:
65                         cpu_clock_freq = 533080000;
66                         break;
67                 case PRID_REV_LOONGSON2F:
68                         cpu_clock_freq = 797000000;
69                         break;
70                 default:
71                         cpu_clock_freq = 100000000;
72                         break;
73                 }
74         }
75
76         pr_info("busclock=%ld, cpuclock=%ld, memsize=%ld, highmemsize=%ld\n",
77                 bus_clock, cpu_clock_freq, memsize, highmemsize);
78 }