linux-stable/arch/mips/rb532/time.c
Thomas Gleixner 41173abc57 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 182
Based on 1 normalized pattern(s):

  this program is free software you can distribute it and or modify it
  under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope it will be useful but without any warranty
  without even the implied warranty of merchantability or fitness for
  a particular purpose see the gnu general public license for more
  details you should have received a copy of the gnu general public
  license along with this program if not write to the free software
  foundation inc 59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 32 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170026.531157061@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:20 -07:00

54 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Carsten Langgaard, carstenl@mips.com
* Copyright (C) 1999,2000 MIPS Technologies, Inc. All rights reserved.
*
* Setting up the clock on the MIPS boards.
*/
#include <linux/init.h>
#include <linux/kernel_stat.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/mc146818rtc.h>
#include <linux/irq.h>
#include <linux/timex.h>
#include <asm/mipsregs.h>
#include <asm/time.h>
#include <asm/mach-rc32434/rc32434.h>
extern unsigned int idt_cpu_freq;
/*
* Figure out the r4k offset, the amount to increment the compare
* register for each time tick. There is no RTC available.
*
* The RC32434 counts at half the CPU *core* speed.
*/
static unsigned long __init cal_r4koff(void)
{
mips_hpt_frequency = idt_cpu_freq * IDT_CLOCK_MULT / 2;
return mips_hpt_frequency / HZ;
}
void __init plat_time_init(void)
{
unsigned int est_freq;
unsigned long flags, r4k_offset;
local_irq_save(flags);
printk(KERN_INFO "calculating r4koff... ");
r4k_offset = cal_r4koff();
printk("%08lx(%d)\n", r4k_offset, (int) r4k_offset);
est_freq = 2 * r4k_offset * HZ;
est_freq += 5000; /* round */
est_freq -= est_freq % 10000;
printk(KERN_INFO "CPU frequency %d.%02d MHz\n", est_freq / 1000000,
(est_freq % 1000000) * 100 / 1000000);
local_irq_restore(flags);
}