diff options
Diffstat (limited to 'arch/mips/loongson/common/env.c')
| -rw-r--r-- | arch/mips/loongson/common/env.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/mips/loongson/common/env.c b/arch/mips/loongson/common/env.c new file mode 100644 index 00000000..d93830ad --- /dev/null +++ b/arch/mips/loongson/common/env.c @@ -0,0 +1,79 @@ +/* + * 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. + * Author: Wu Zhangjin, wuzhangjin@gmail.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 { \ + unsigned int tmp __maybe_unused; \ + \ + if (strncmp(option, (char *)p, strlen(option)) == 0) \ + tmp = 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 = (¤t_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); +} |