// 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();
|
}
|
