arch/loongarch/include/asm/time.h

   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
  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
  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 */