linux/linux-5.18.11/arch/mips/loongson2ef/common/env.c

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2024-03-22 18:12:32 +00:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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. & Institute of Computing Technology
* Author: Fuxin Zhang, zhangfx@lemote.com
*
* Copyright (C) 2009 Lemote Inc.
* Author: Wu Zhangjin, wuzhangjin@gmail.com
*/
#include <linux/export.h>
#include <asm/bootinfo.h>
#include <asm/fw/fw.h>
#include <loongson.h>
u32 cpu_clock_freq;
EXPORT_SYMBOL(cpu_clock_freq);
void __init prom_init_env(void)
{
/* pmon passes arguments in 32bit pointers */
unsigned int processor_id;
cpu_clock_freq = fw_getenvl("cpuclock");
memsize = fw_getenvl("memsize");
highmemsize = fw_getenvl("highmemsize");
if (memsize == 0)
memsize = 256;
pr_info("memsize=%u, highmemsize=%u\n", memsize, highmemsize);
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("CpuClock = %u\n", cpu_clock_freq);
}