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Linux kernel mirror (for testing)
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linux
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 u64 decrementer_max;
22
23extern unsigned long tb_ticks_per_jiffy;
24extern unsigned long tb_ticks_per_usec;
25extern unsigned long tb_ticks_per_sec;
26extern struct clock_event_device decrementer_clockevent;
27extern u64 decrementer_max;
28
29
30extern void generic_calibrate_decr(void);
31
32/* Some sane defaults: 125 MHz timebase, 1GHz processor */
33extern unsigned long ppc_proc_freq;
34#define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
35extern unsigned long ppc_tb_freq;
36#define DEFAULT_TB_FREQ 125000000UL
37
38extern bool tb_invalid;
39
40struct div_result {
41 u64 result_high;
42 u64 result_low;
43};
44
45static inline u64 get_vtb(void)
46{
47 if (cpu_has_feature(CPU_FTR_ARCH_207S))
48 return mfspr(SPRN_VTB);
49
50 return 0;
51}
52
53/* Accessor functions for the decrementer register.
54 * The 4xx doesn't even have a decrementer. I tried to use the
55 * generic timer interrupt code, which seems OK, with the 4xx PIT
56 * in auto-reload mode. The problem is PIT stops counting when it
57 * hits zero. If it would wrap, we could use it just like a decrementer.
58 */
59static inline u64 get_dec(void)
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_BOOKE))
72 mtspr(SPRN_DEC, val);
73 else
74 mtspr(SPRN_DEC, val - 1);
75}
76
77static inline unsigned long tb_ticks_since(unsigned long tstamp)
78{
79 return mftb() - tstamp;
80}
81
82#define mulhwu(x,y) \
83({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
84
85#ifdef CONFIG_PPC64
86#define mulhdu(x,y) \
87({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
88#else
89#define mulhdu(x, y) mul_u64_u64_shr(x, y, 64)
90#endif
91
92extern void div128_by_32(u64 dividend_high, u64 dividend_low,
93 unsigned divisor, struct div_result *dr);
94
95extern void secondary_cpu_time_init(void);
96extern void __init time_init(void);
97
98DECLARE_PER_CPU(u64, decrementers_next_tb);
99
100static inline u64 timer_get_next_tb(void)
101{
102 return __this_cpu_read(decrementers_next_tb);
103}
104
105#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
106void timer_rearm_host_dec(u64 now);
107#endif
108
109/* Convert timebase ticks to nanoseconds */
110unsigned long long tb_to_ns(unsigned long long tb_ticks);
111
112void timer_broadcast_interrupt(void);
113
114/* SPLPAR and VIRT_CPU_ACCOUNTING_NATIVE */
115void pseries_accumulate_stolen_time(void);
116u64 pseries_calculate_stolen_time(u64 stop_tb);
117
118#endif /* __KERNEL__ */
119#endif /* __POWERPC_TIME_H */