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