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 */
20 extern unsigned long tb_ticks_per_jiffy;
21 extern unsigned long tb_ticks_per_usec;
22 extern unsigned long tb_ticks_per_sec;
23 extern struct clock_event_device decrementer_clockevent;
24
25
26 extern void generic_calibrate_decr(void);
27
28 /* Some sane defaults: 125 MHz timebase, 1GHz processor */
29 extern unsigned long ppc_proc_freq;
30 #define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
31 extern unsigned long ppc_tb_freq;
32 #define DEFAULT_TB_FREQ 125000000UL
33
34 extern bool tb_invalid;
35
36 struct div_result {
37 u64 result_high;
38 u64 result_low;
39 };
40
41 /* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
get_tbl(void)42 static inline unsigned long get_tbl(void)
43 {
44 return mftb();
45 }
46
get_vtb(void)47 static inline u64 get_vtb(void)
48 {
49 #ifdef CONFIG_PPC_BOOK3S_64
50 if (cpu_has_feature(CPU_FTR_ARCH_207S))
51 return mfspr(SPRN_VTB);
52 #endif
53 return 0;
54 }
55
get_tb(void)56 static inline u64 get_tb(void)
57 {
58 unsigned int tbhi, tblo, tbhi2;
59
60 if (IS_ENABLED(CONFIG_PPC64))
61 return mftb();
62
63 do {
64 tbhi = mftbu();
65 tblo = mftb();
66 tbhi2 = mftbu();
67 } while (tbhi != tbhi2);
68
69 return ((u64)tbhi << 32) | tblo;
70 }
71
set_tb(unsigned int upper,unsigned int lower)72 static inline void set_tb(unsigned int upper, unsigned int lower)
73 {
74 mtspr(SPRN_TBWL, 0);
75 mtspr(SPRN_TBWU, upper);
76 mtspr(SPRN_TBWL, lower);
77 }
78
79 /* Accessor functions for the decrementer register.
80 * The 4xx doesn't even have a decrementer. I tried to use the
81 * generic timer interrupt code, which seems OK, with the 4xx PIT
82 * in auto-reload mode. The problem is PIT stops counting when it
83 * hits zero. If it would wrap, we could use it just like a decrementer.
84 */
get_dec(void)85 static inline u64 get_dec(void)
86 {
87 if (IS_ENABLED(CONFIG_40x))
88 return mfspr(SPRN_PIT);
89
90 return mfspr(SPRN_DEC);
91 }
92
93 /*
94 * Note: Book E and 4xx processors differ from other PowerPC processors
95 * in when the decrementer generates its interrupt: on the 1 to 0
96 * transition for Book E/4xx, but on the 0 to -1 transition for others.
97 */
set_dec(u64 val)98 static inline void set_dec(u64 val)
99 {
100 if (IS_ENABLED(CONFIG_40x))
101 mtspr(SPRN_PIT, (u32)val);
102 else if (IS_ENABLED(CONFIG_BOOKE))
103 mtspr(SPRN_DEC, val);
104 else
105 mtspr(SPRN_DEC, val - 1);
106 }
107
tb_ticks_since(unsigned long tstamp)108 static inline unsigned long tb_ticks_since(unsigned long tstamp)
109 {
110 return mftb() - tstamp;
111 }
112
113 #define mulhwu(x,y) \
114 ({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
115
116 #ifdef CONFIG_PPC64
117 #define mulhdu(x,y) \
118 ({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
119 #else
120 extern u64 mulhdu(u64, u64);
121 #endif
122
123 extern void div128_by_32(u64 dividend_high, u64 dividend_low,
124 unsigned divisor, struct div_result *dr);
125
126 extern void secondary_cpu_time_init(void);
127 extern void __init time_init(void);
128
129 DECLARE_PER_CPU(u64, decrementers_next_tb);
130
131 /* Convert timebase ticks to nanoseconds */
132 unsigned long long tb_to_ns(unsigned long long tb_ticks);
133
134 /* SPLPAR */
135 void accumulate_stolen_time(void);
136
137 #endif /* __KERNEL__ */
138 #endif /* __POWERPC_TIME_H */
139
