Linux kernel mirror (for testing)
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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#ifdef CONFIG_PPC_SPLPAR
33extern u64 get_boot_tb(void);
34#endif
35
36/* Some sane defaults: 125 MHz timebase, 1GHz processor */
37extern unsigned long ppc_proc_freq;
38#define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
39extern unsigned long ppc_tb_freq;
40#define DEFAULT_TB_FREQ 125000000UL
41
42extern bool tb_invalid;
43
44struct div_result {
45 u64 result_high;
46 u64 result_low;
47};
48
49static inline u64 get_vtb(void)
50{
51 if (cpu_has_feature(CPU_FTR_ARCH_207S))
52 return mfspr(SPRN_VTB);
53
54 return 0;
55}
56
57/* Accessor functions for the decrementer register.
58 * The 4xx doesn't even have a decrementer. I tried to use the
59 * generic timer interrupt code, which seems OK, with the 4xx PIT
60 * in auto-reload mode. The problem is PIT stops counting when it
61 * hits zero. If it would wrap, we could use it just like a decrementer.
62 */
63static inline u64 get_dec(void)
64{
65 return mfspr(SPRN_DEC);
66}
67
68/*
69 * Note: Book E and 4xx processors differ from other PowerPC processors
70 * in when the decrementer generates its interrupt: on the 1 to 0
71 * transition for Book E/4xx, but on the 0 to -1 transition for others.
72 */
73static inline void set_dec(u64 val)
74{
75 if (IS_ENABLED(CONFIG_BOOKE))
76 mtspr(SPRN_DEC, val);
77 else
78 mtspr(SPRN_DEC, val - 1);
79}
80
81static inline unsigned long tb_ticks_since(unsigned long tstamp)
82{
83 return mftb() - tstamp;
84}
85
86#define mulhwu(x,y) \
87({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
88
89#ifdef CONFIG_PPC64
90#define mulhdu(x,y) \
91({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
92#else
93#define mulhdu(x, y) mul_u64_u64_shr(x, y, 64)
94#endif
95
96extern void secondary_cpu_time_init(void);
97extern void __init time_init(void);
98
99DECLARE_PER_CPU(u64, decrementers_next_tb);
100
101static inline u64 timer_get_next_tb(void)
102{
103 return __this_cpu_read(decrementers_next_tb);
104}
105
106#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
107void timer_rearm_host_dec(u64 now);
108#endif
109
110/* Convert timebase ticks to nanoseconds */
111unsigned long long tb_to_ns(unsigned long long tb_ticks);
112
113void timer_broadcast_interrupt(void);
114
115/* SPLPAR and VIRT_CPU_ACCOUNTING_NATIVE */
116void pseries_accumulate_stolen_time(void);
117u64 pseries_calculate_stolen_time(u64 stop_tb);
118
119#endif /* __KERNEL__ */
120#endif /* __POWERPC_TIME_H */