1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
8 #include <linux/clockchips.h>
9 #include <linux/clocksource.h>
10 #include <asm/loongarch.h>
12 extern u64 cpu_clock_freq;
13 extern u64 const_clock_freq;
15 extern void save_counter(void);
16 extern void sync_counter(void);
18 static inline unsigned int calc_const_freq(void)
21 unsigned int base_freq;
22 unsigned int cfm, cfd;
24 res = read_cpucfg(LOONGARCH_CPUCFG2);
25 if (!(res & CPUCFG2_LLFTP))
28 base_freq = read_cpucfg(LOONGARCH_CPUCFG4);
29 res = read_cpucfg(LOONGARCH_CPUCFG5);
31 cfd = (res >> 16) & 0xffff;
33 if (!base_freq || !cfm || !cfd)
36 return (base_freq * cfm / cfd);
40 * Initialize the calling CPU's timer interrupt as clockevent device
42 extern int constant_clockevent_init(void);
43 extern int constant_clocksource_init(void);
45 static inline void clockevent_set_clock(struct clock_event_device *cd,
48 clockevents_calc_mult_shift(cd, clock, 4);
51 #endif /* _ASM_TIME_H */