arch/loongarch/include/asm/time.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
 */
#ifndef _ASM_TIME_H
#define _ASM_TIME_H

#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <asm/loongarch.h>

extern u64 cpu_clock_freq;
extern u64 const_clock_freq;

extern void save_counter(void);
extern void sync_counter(void);

static inline unsigned int calc_const_freq(void)
{
	unsigned int res;
	unsigned int base_freq;
	unsigned int cfm, cfd;

	res = read_cpucfg(LOONGARCH_CPUCFG2);
	if (!(res & CPUCFG2_LLFTP))
		return 0;

	base_freq = read_cpucfg(LOONGARCH_CPUCFG4);
	res = read_cpucfg(LOONGARCH_CPUCFG5);
	cfm = res & 0xffff;
	cfd = (res >> 16) & 0xffff;

	if (!base_freq || !cfm || !cfd)
		return 0;

	return (base_freq * cfm / cfd);
}

/*
 * Initialize the calling CPU's timer interrupt as clockevent device
 */
extern int constant_clockevent_init(void);
extern int constant_clocksource_init(void);

static inline void clockevent_set_clock(struct clock_event_device *cd,
					unsigned int clock)
{
	clockevents_calc_mult_shift(cd, clock, 4);
}

#endif /* _ASM_TIME_H */