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 #ifdef CONFIG_PPC_SPLPAR
33 extern u64 get_boot_tb(void);
34 #endif
35
36 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
37 extern unsigned long ppc_proc_freq;
38 #define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
39 extern unsigned long ppc_tb_freq;
40 #define DEFAULT_TB_FREQ 125000000UL
41
42 extern bool tb_invalid;
43
44 struct div_result {
45 u64 result_high;
46 u64 result_low;
47 };
48
get_vtb(void)49 static 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 */
get_dec(void)63 static 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 */
set_dec(u64 val)73 static 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
tb_ticks_since(unsigned long tstamp)81 static 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
96 extern void secondary_cpu_time_init(void);
97 extern void __init time_init(void);
98
99 DECLARE_PER_CPU(u64, decrementers_next_tb);
100
timer_get_next_tb(void)101 static 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
107 void timer_rearm_host_dec(u64 now);
108 #endif
109
110 /* Convert timebase ticks to nanoseconds */
111 unsigned long long tb_to_ns(unsigned long long tb_ticks);
112
113 void timer_broadcast_interrupt(void);
114
115 /* SPLPAR and VIRT_CPU_ACCOUNTING_NATIVE */
116 void pseries_accumulate_stolen_time(void);
117 u64 pseries_calculate_stolen_time(u64 stop_tb);
118
119 #endif /* __KERNEL__ */
120 #endif /* __POWERPC_TIME_H */
121