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 unsigned long tb_ticks_per_jiffy;
22 extern unsigned long tb_ticks_per_usec;
23 extern unsigned long tb_ticks_per_sec;
24 extern struct clock_event_device decrementer_clockevent;
25
26
27 extern void generic_calibrate_decr(void);
28
29 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
30 extern unsigned long ppc_proc_freq;
31 #define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
32 extern unsigned long ppc_tb_freq;
33 #define DEFAULT_TB_FREQ 125000000UL
34
35 extern bool tb_invalid;
36
37 struct div_result {
38 u64 result_high;
39 u64 result_low;
40 };
41
get_vtb(void)42 static inline u64 get_vtb(void)
43 {
44 if (cpu_has_feature(CPU_FTR_ARCH_207S))
45 return mfspr(SPRN_VTB);
46
47 return 0;
48 }
49
50 /* Accessor functions for the decrementer register.
51 * The 4xx doesn't even have a decrementer. I tried to use the
52 * generic timer interrupt code, which seems OK, with the 4xx PIT
53 * in auto-reload mode. The problem is PIT stops counting when it
54 * hits zero. If it would wrap, we could use it just like a decrementer.
55 */
get_dec(void)56 static inline u64 get_dec(void)
57 {
58 if (IS_ENABLED(CONFIG_40x))
59 return mfspr(SPRN_PIT);
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 */
set_dec(u64 val)69 static inline void set_dec(u64 val)
70 {
71 if (IS_ENABLED(CONFIG_40x))
72 mtspr(SPRN_PIT, (u32)val);
73 else if (IS_ENABLED(CONFIG_BOOKE))
74 mtspr(SPRN_DEC, val);
75 else
76 mtspr(SPRN_DEC, val - 1);
77 }
78
tb_ticks_since(unsigned long tstamp)79 static inline unsigned long tb_ticks_since(unsigned long tstamp)
80 {
81 return mftb() - tstamp;
82 }
83
84 #define mulhwu(x,y) \
85 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
86
87 #ifdef CONFIG_PPC64
88 #define mulhdu(x,y) \
89 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
90 #else
91 extern u64 mulhdu(u64, u64);
92 #endif
93
94 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
95 unsigned divisor, struct div_result *dr);
96
97 extern void secondary_cpu_time_init(void);
98 extern void __init time_init(void);
99
100 DECLARE_PER_CPU(u64, decrementers_next_tb);
101
102 /* Convert timebase ticks to nanoseconds */
103 unsigned long long tb_to_ns(unsigned long long tb_ticks);
104
105 void timer_broadcast_interrupt(void);
106
107 /* SPLPAR */
108 void accumulate_stolen_time(void);
109
110 #endif /* __KERNEL__ */
111 #endif /* __POWERPC_TIME_H */
112