LXR linux/arch/powerpc/include/asm/time.h

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 * Common time prototypes and such for all ppc machines.
   4 *
   5 * Written by Cort Dougan (cort@cs.nmt.edu) to merge
   6 * Paul Mackerras' version and mine for PReP and Pmac.
   7 */
   8
   9#ifndef __POWERPC_TIME_H
  10#define __POWERPC_TIME_H
  11
  12#ifdef __KERNEL__
  13#include <linux/types.h>
  14#include <linux/percpu.h>
  15
  16#include <asm/processor.h>
  17#include <asm/cpu_has_feature.h>
  18#include <asm/vdso/timebase.h>
  19
  20/* time.c */
  21extern unsigned long tb_ticks_per_jiffy;
  22extern unsigned long tb_ticks_per_usec;
  23extern unsigned long tb_ticks_per_sec;
  24extern struct clock_event_device decrementer_clockevent;
  25
  26
  27extern void generic_calibrate_decr(void);
  28
  29/* Some sane defaults: 125 MHz timebase, 1GHz processor */
  30extern unsigned long ppc_proc_freq;
  31#define DEFAULT_PROC_FREQ       (DEFAULT_TB_FREQ * 8)
  32extern unsigned long ppc_tb_freq;
  33#define DEFAULT_TB_FREQ         125000000UL
  34
  35extern bool tb_invalid;
  36
  37struct div_result {
  38        u64 result_high;
  39        u64 result_low;
  40};
  41
  42static inline u64 get_vtb(void)
  43{
  44        if (cpu_has_feature(CPU_FTR_ARCH_207S))
  45                return mfspr(SPRN_VTB);
  46
  47        return 0;
  48}
  49
  50/* Accessor functions for the decrementer register.
  51 * The 4xx doesn't even have a decrementer.  I tried to use the
  52 * generic timer interrupt code, which seems OK, with the 4xx PIT
  53 * in auto-reload mode.  The problem is PIT stops counting when it
  54 * hits zero.  If it would wrap, we could use it just like a decrementer.
  55 */
  56static inline u64 get_dec(void)
  57{
  58        if (IS_ENABLED(CONFIG_40x))
  59                return mfspr(SPRN_PIT);
  60
  61        return mfspr(SPRN_DEC);
  62}
  63
  64/*
  65 * Note: Book E and 4xx processors differ from other PowerPC processors
  66 * in when the decrementer generates its interrupt: on the 1 to 0
  67 * transition for Book E/4xx, but on the 0 to -1 transition for others.
  68 */
  69static inline void set_dec(u64 val)
  70{
  71        if (IS_ENABLED(CONFIG_40x))
  72                mtspr(SPRN_PIT, (u32)val);
  73        else if (IS_ENABLED(CONFIG_BOOKE))
  74                mtspr(SPRN_DEC, val);
  75        else
  76                mtspr(SPRN_DEC, val - 1);
  77}
  78
  79static inline unsigned long tb_ticks_since(unsigned long tstamp)
  80{
  81        return mftb() - tstamp;
  82}
  83
  84#define mulhwu(x,y) \
  85({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
  86
  87#ifdef CONFIG_PPC64
  88#define mulhdu(x,y) \
  89({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
  90#else
  91extern u64 mulhdu(u64, u64);
  92#endif
  93
  94extern void div128_by_32(u64 dividend_high, u64 dividend_low,
  95                         unsigned divisor, struct div_result *dr);
  96
  97extern void secondary_cpu_time_init(void);
  98extern void __init time_init(void);
  99
 100#ifdef CONFIG_PPC64
 101static inline unsigned long test_irq_work_pending(void)
 102{
 103        unsigned long x;
 104
 105        asm volatile("lbz %0,%1(13)"
 106                : "=r" (x)
 107                : "i" (offsetof(struct paca_struct, irq_work_pending)));
 108        return x;
 109}
 110#endif
 111
 112DECLARE_PER_CPU(u64, decrementers_next_tb);
 113
 114/* Convert timebase ticks to nanoseconds */
 115unsigned long long tb_to_ns(unsigned long long tb_ticks);
 116
 117void timer_broadcast_interrupt(void);
 118
 119/* SPLPAR */
 120void accumulate_stolen_time(void);
 121
 122#endif /* __KERNEL__ */
 123#endif /* __POWERPC_TIME_H */
 124