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 */
21 extern u64 decrementer_max;
22
23 extern unsigned long tb_ticks_per_jiffy;
24 extern unsigned long tb_ticks_per_usec;
25 extern unsigned long tb_ticks_per_sec;
26 extern struct clock_event_device decrementer_clockevent;
27 extern u64 decrementer_max;
28
29
30 extern void generic_calibrate_decr(void);
31
32 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
33 extern unsigned long ppc_proc_freq;
34 #define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
35 extern unsigned long ppc_tb_freq;
36 #define DEFAULT_TB_FREQ 125000000UL
37
38 extern bool tb_invalid;
39
40 struct div_result {
41 u64 result_high;
42 u64 result_low;
43 };
44
get_vtb(void)45 static 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 */
get_dec(void)59 static inline u64 get_dec(void)
60 {
61 if (IS_ENABLED(CONFIG_40x))
62 return mfspr(SPRN_PIT);
63
64 return mfspr(SPRN_DEC);
65 }
66
67 /*
68 * Note: Book E and 4xx processors differ from other PowerPC processors
69 * in when the decrementer generates its interrupt: on the 1 to 0
70 * transition for Book E/4xx, but on the 0 to -1 transition for others.
71 */
set_dec(u64 val)72 static inline void set_dec(u64 val)
73 {
74 if (IS_ENABLED(CONFIG_40x))
75 mtspr(SPRN_PIT, (u32)val);
76 else if (IS_ENABLED(CONFIG_BOOKE))
77 mtspr(SPRN_DEC, val);
78 else
79 mtspr(SPRN_DEC, val - 1);
80 }
81
tb_ticks_since(unsigned long tstamp)82 static inline unsigned long tb_ticks_since(unsigned long tstamp)
83 {
84 return mftb() - tstamp;
85 }
86
87 #define mulhwu(x,y) \
88 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
89
90 #ifdef CONFIG_PPC64
91 #define mulhdu(x,y) \
92 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
93 #else
94 extern u64 mulhdu(u64, u64);
95 #endif
96
97 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
98 unsigned divisor, struct div_result *dr);
99
100 extern void secondary_cpu_time_init(void);
101 extern void __init time_init(void);
102
103 DECLARE_PER_CPU(u64, decrementers_next_tb);
104
timer_get_next_tb(void)105 static inline u64 timer_get_next_tb(void)
106 {
107 return __this_cpu_read(decrementers_next_tb);
108 }
109
110 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
111 void timer_rearm_host_dec(u64 now);
112 #endif
113
114 /* Convert timebase ticks to nanoseconds */
115 unsigned long long tb_to_ns(unsigned long long tb_ticks);
116
117 void timer_broadcast_interrupt(void);
118
119 /* SPLPAR and VIRT_CPU_ACCOUNTING_NATIVE */
120 void pseries_accumulate_stolen_time(void);
121 u64 pseries_calculate_stolen_time(u64 stop_tb);
122
123 #endif /* __KERNEL__ */
124 #endif /* __POWERPC_TIME_H */
125