xref: /openbmc/linux/arch/loongarch/include/asm/time.h (revision 366bb35a)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
4  */
5 #ifndef _ASM_TIME_H
6 #define _ASM_TIME_H
7 
8 #include <linux/clockchips.h>
9 #include <linux/clocksource.h>
10 #include <asm/loongarch.h>
11 
12 extern u64 cpu_clock_freq;
13 extern u64 const_clock_freq;
14 
15 extern void save_counter(void);
16 extern void sync_counter(void);
17 
calc_const_freq(void)18 static inline unsigned int calc_const_freq(void)
19 {
20 	unsigned int res;
21 	unsigned int base_freq;
22 	unsigned int cfm, cfd;
23 
24 	res = read_cpucfg(LOONGARCH_CPUCFG2);
25 	if (!(res & CPUCFG2_LLFTP))
26 		return 0;
27 
28 	base_freq = read_cpucfg(LOONGARCH_CPUCFG4);
29 	res = read_cpucfg(LOONGARCH_CPUCFG5);
30 	cfm = res & 0xffff;
31 	cfd = (res >> 16) & 0xffff;
32 
33 	if (!base_freq || !cfm || !cfd)
34 		return 0;
35 
36 	return (base_freq * cfm / cfd);
37 }
38 
39 /*
40  * Initialize the calling CPU's timer interrupt as clockevent device
41  */
42 extern int constant_clockevent_init(void);
43 extern int constant_clocksource_init(void);
44 
clockevent_set_clock(struct clock_event_device * cd,unsigned int clock)45 static inline void clockevent_set_clock(struct clock_event_device *cd,
46 					unsigned int clock)
47 {
48 	clockevents_calc_mult_shift(cd, clock, 4);
49 }
50 
51 #endif /* _ASM_TIME_H */
52