xref: /OK3568_Linux_fs/kernel/arch/mips/loongson2ef/common/env.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Based on Ocelot Linux port, which is
4*4882a593Smuzhiyun  * Copyright 2001 MontaVista Software Inc.
5*4882a593Smuzhiyun  * Author: jsun@mvista.com or jsun@junsun.net
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * Copyright 2003 ICT CAS
8*4882a593Smuzhiyun  * Author: Michael Guo <guoyi@ict.ac.cn>
9*4882a593Smuzhiyun  *
10*4882a593Smuzhiyun  * Copyright (C) 2007 Lemote Inc. & Institute of Computing Technology
11*4882a593Smuzhiyun  * Author: Fuxin Zhang, zhangfx@lemote.com
12*4882a593Smuzhiyun  *
13*4882a593Smuzhiyun  * Copyright (C) 2009 Lemote Inc.
14*4882a593Smuzhiyun  * Author: Wu Zhangjin, wuzhangjin@gmail.com
15*4882a593Smuzhiyun  */
16*4882a593Smuzhiyun #include <linux/export.h>
17*4882a593Smuzhiyun #include <asm/bootinfo.h>
18*4882a593Smuzhiyun #include <asm/fw/fw.h>
19*4882a593Smuzhiyun #include <loongson.h>
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun u32 cpu_clock_freq;
22*4882a593Smuzhiyun EXPORT_SYMBOL(cpu_clock_freq);
23*4882a593Smuzhiyun 
prom_init_env(void)24*4882a593Smuzhiyun void __init prom_init_env(void)
25*4882a593Smuzhiyun {
26*4882a593Smuzhiyun 	/* pmon passes arguments in 32bit pointers */
27*4882a593Smuzhiyun 	unsigned int processor_id;
28*4882a593Smuzhiyun 
29*4882a593Smuzhiyun 	cpu_clock_freq = fw_getenvl("cpuclock");
30*4882a593Smuzhiyun 	memsize = fw_getenvl("memsize");
31*4882a593Smuzhiyun 	highmemsize = fw_getenvl("highmemsize");
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun 	if (memsize == 0)
34*4882a593Smuzhiyun 		memsize = 256;
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun 	pr_info("memsize=%u, highmemsize=%u\n", memsize, highmemsize);
37*4882a593Smuzhiyun 
38*4882a593Smuzhiyun 	if (cpu_clock_freq == 0) {
39*4882a593Smuzhiyun 		processor_id = (&current_cpu_data)->processor_id;
40*4882a593Smuzhiyun 		switch (processor_id & PRID_REV_MASK) {
41*4882a593Smuzhiyun 		case PRID_REV_LOONGSON2E:
42*4882a593Smuzhiyun 			cpu_clock_freq = 533080000;
43*4882a593Smuzhiyun 			break;
44*4882a593Smuzhiyun 		case PRID_REV_LOONGSON2F:
45*4882a593Smuzhiyun 			cpu_clock_freq = 797000000;
46*4882a593Smuzhiyun 			break;
47*4882a593Smuzhiyun 		default:
48*4882a593Smuzhiyun 			cpu_clock_freq = 100000000;
49*4882a593Smuzhiyun 			break;
50*4882a593Smuzhiyun 		}
51*4882a593Smuzhiyun 	}
52*4882a593Smuzhiyun 	pr_info("CpuClock = %u\n", cpu_clock_freq);
53*4882a593Smuzhiyun }
54