linux/arch/c6x/kernel/time.c
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute 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 free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00

64 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Port on Texas Instruments TMS320C6x architecture
*
* Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
* Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
*/
#include <linux/kernel.h>
#include <linux/clocksource.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/timex.h>
#include <linux/profile.h>
#include <asm/special_insns.h>
#include <asm/timer64.h>
static u32 sched_clock_multiplier;
#define SCHED_CLOCK_SHIFT 16
static u64 tsc_read(struct clocksource *cs)
{
return get_cycles();
}
static struct clocksource clocksource_tsc = {
.name = "timestamp",
.rating = 300,
.read = tsc_read,
.mask = CLOCKSOURCE_MASK(64),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
/*
* scheduler clock - returns current time in nanoseconds.
*/
u64 sched_clock(void)
{
u64 tsc = get_cycles();
return (tsc * sched_clock_multiplier) >> SCHED_CLOCK_SHIFT;
}
void __init time_init(void)
{
u64 tmp = (u64)NSEC_PER_SEC << SCHED_CLOCK_SHIFT;
do_div(tmp, c6x_core_freq);
sched_clock_multiplier = tmp;
clocksource_register_hz(&clocksource_tsc, c6x_core_freq);
/* write anything into TSCL to enable counting */
set_creg(TSCL, 0);
/* probe for timer64 event timer */
timer64_init();
}