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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
19/* time.c */
20extern unsigned long tb_ticks_per_jiffy;
21extern unsigned long tb_ticks_per_usec;
22extern unsigned long tb_ticks_per_sec;
23extern struct clock_event_device decrementer_clockevent;
24
25
26extern void generic_calibrate_decr(void);
27
28/* Some sane defaults: 125 MHz timebase, 1GHz processor */
29extern unsigned long ppc_proc_freq;
30#define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
31extern unsigned long ppc_tb_freq;
32#define DEFAULT_TB_FREQ 125000000UL
33
34extern bool tb_invalid;
35
36struct div_result {
37 u64 result_high;
38 u64 result_low;
39};
40
41/* Accessor functions for the timebase (RTC on 601) registers. */
42/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
43#define __USE_RTC() (IS_ENABLED(CONFIG_PPC_BOOK3S_601))
44
45#ifdef CONFIG_PPC64
46
47/* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
48#define get_tbl get_tb
49
50#else
51
52static inline unsigned long get_tbl(void)
53{
54 return mftbl();
55}
56
57static inline unsigned int get_tbu(void)
58{
59 return mftbu();
60}
61#endif /* !CONFIG_PPC64 */
62
63static inline unsigned int get_rtcl(void)
64{
65 unsigned int rtcl;
66
67 asm volatile("mfrtcl %0" : "=r" (rtcl));
68 return rtcl;
69}
70
71static inline u64 get_rtc(void)
72{
73 unsigned int hi, lo, hi2;
74
75 do {
76 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
77 : "=r" (hi), "=r" (lo), "=r" (hi2));
78 } while (hi2 != hi);
79 return (u64)hi * 1000000000 + lo;
80}
81
82static inline u64 get_vtb(void)
83{
84#ifdef CONFIG_PPC_BOOK3S_64
85 if (cpu_has_feature(CPU_FTR_ARCH_207S))
86 return mfspr(SPRN_VTB);
87#endif
88 return 0;
89}
90
91#ifdef CONFIG_PPC64
92static inline u64 get_tb(void)
93{
94 return mftb();
95}
96#else /* CONFIG_PPC64 */
97static inline u64 get_tb(void)
98{
99 unsigned int tbhi, tblo, tbhi2;
100
101 do {
102 tbhi = get_tbu();
103 tblo = get_tbl();
104 tbhi2 = get_tbu();
105 } while (tbhi != tbhi2);
106
107 return ((u64)tbhi << 32) | tblo;
108}
109#endif /* !CONFIG_PPC64 */
110
111static inline u64 get_tb_or_rtc(void)
112{
113 return __USE_RTC() ? get_rtc() : get_tb();
114}
115
116static inline void set_tb(unsigned int upper, unsigned int lower)
117{
118 mtspr(SPRN_TBWL, 0);
119 mtspr(SPRN_TBWU, upper);
120 mtspr(SPRN_TBWL, lower);
121}
122
123/* Accessor functions for the decrementer register.
124 * The 4xx doesn't even have a decrementer. I tried to use the
125 * generic timer interrupt code, which seems OK, with the 4xx PIT
126 * in auto-reload mode. The problem is PIT stops counting when it
127 * hits zero. If it would wrap, we could use it just like a decrementer.
128 */
129static inline u64 get_dec(void)
130{
131#if defined(CONFIG_40x)
132 return (mfspr(SPRN_PIT));
133#else
134 return (mfspr(SPRN_DEC));
135#endif
136}
137
138/*
139 * Note: Book E and 4xx processors differ from other PowerPC processors
140 * in when the decrementer generates its interrupt: on the 1 to 0
141 * transition for Book E/4xx, but on the 0 to -1 transition for others.
142 */
143static inline void set_dec(u64 val)
144{
145#if defined(CONFIG_40x)
146 mtspr(SPRN_PIT, (u32) val);
147#else
148#ifndef CONFIG_BOOKE
149 --val;
150#endif
151 mtspr(SPRN_DEC, val);
152#endif /* not 40x */
153}
154
155static inline unsigned long tb_ticks_since(unsigned long tstamp)
156{
157 if (__USE_RTC()) {
158 int delta = get_rtcl() - (unsigned int) tstamp;
159 return delta < 0 ? delta + 1000000000 : delta;
160 }
161 return get_tbl() - tstamp;
162}
163
164#define mulhwu(x,y) \
165({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
166
167#ifdef CONFIG_PPC64
168#define mulhdu(x,y) \
169({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
170#else
171extern u64 mulhdu(u64, u64);
172#endif
173
174extern void div128_by_32(u64 dividend_high, u64 dividend_low,
175 unsigned divisor, struct div_result *dr);
176
177extern void secondary_cpu_time_init(void);
178extern void __init time_init(void);
179
180DECLARE_PER_CPU(u64, decrementers_next_tb);
181
182/* Convert timebase ticks to nanoseconds */
183unsigned long long tb_to_ns(unsigned long long tb_ticks);
184
185/* SPLPAR */
186void accumulate_stolen_time(void);
187
188#endif /* __KERNEL__ */
189#endif /* __POWERPC_TIME_H */