Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Common time prototypes and such for all ppc machines.
3 *
4 * Written by Cort Dougan (cort@cs.nmt.edu) to merge
5 * Paul Mackerras' version and mine for PReP and Pmac.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13#ifndef __POWERPC_TIME_H
14#define __POWERPC_TIME_H
15
16#ifdef __KERNEL__
17#include <linux/types.h>
18#include <linux/percpu.h>
19
20#include <asm/processor.h>
21#include <asm/cpu_has_feature.h>
22
23/* time.c */
24extern unsigned long tb_ticks_per_jiffy;
25extern unsigned long tb_ticks_per_usec;
26extern unsigned long tb_ticks_per_sec;
27extern struct clock_event_device decrementer_clockevent;
28
29
30extern void generic_calibrate_decr(void);
31extern void hdec_interrupt(struct pt_regs *regs);
32
33/* Some sane defaults: 125 MHz timebase, 1GHz processor */
34extern unsigned long ppc_proc_freq;
35#define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
36extern unsigned long ppc_tb_freq;
37#define DEFAULT_TB_FREQ 125000000UL
38
39extern bool tb_invalid;
40
41struct div_result {
42 u64 result_high;
43 u64 result_low;
44};
45
46/* Accessor functions for the timebase (RTC on 601) registers. */
47/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
48#ifdef CONFIG_PPC_BOOK3S_32
49#define __USE_RTC() (cpu_has_feature(CPU_FTR_USE_RTC))
50#else
51#define __USE_RTC() 0
52#endif
53
54#ifdef CONFIG_PPC64
55
56/* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
57#define get_tbl get_tb
58
59#else
60
61static inline unsigned long get_tbl(void)
62{
63#if defined(CONFIG_403GCX)
64 unsigned long tbl;
65 asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
66 return tbl;
67#else
68 return mftbl();
69#endif
70}
71
72static inline unsigned int get_tbu(void)
73{
74#ifdef CONFIG_403GCX
75 unsigned int tbu;
76 asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
77 return tbu;
78#else
79 return mftbu();
80#endif
81}
82#endif /* !CONFIG_PPC64 */
83
84static inline unsigned int get_rtcl(void)
85{
86 unsigned int rtcl;
87
88 asm volatile("mfrtcl %0" : "=r" (rtcl));
89 return rtcl;
90}
91
92static inline u64 get_rtc(void)
93{
94 unsigned int hi, lo, hi2;
95
96 do {
97 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
98 : "=r" (hi), "=r" (lo), "=r" (hi2));
99 } while (hi2 != hi);
100 return (u64)hi * 1000000000 + lo;
101}
102
103static inline u64 get_vtb(void)
104{
105#ifdef CONFIG_PPC_BOOK3S_64
106 if (cpu_has_feature(CPU_FTR_ARCH_207S))
107 return mfspr(SPRN_VTB);
108#endif
109 return 0;
110}
111
112#ifdef CONFIG_PPC64
113static inline u64 get_tb(void)
114{
115 return mftb();
116}
117#else /* CONFIG_PPC64 */
118static inline u64 get_tb(void)
119{
120 unsigned int tbhi, tblo, tbhi2;
121
122 do {
123 tbhi = get_tbu();
124 tblo = get_tbl();
125 tbhi2 = get_tbu();
126 } while (tbhi != tbhi2);
127
128 return ((u64)tbhi << 32) | tblo;
129}
130#endif /* !CONFIG_PPC64 */
131
132static inline u64 get_tb_or_rtc(void)
133{
134 return __USE_RTC() ? get_rtc() : get_tb();
135}
136
137static inline void set_tb(unsigned int upper, unsigned int lower)
138{
139 mtspr(SPRN_TBWL, 0);
140 mtspr(SPRN_TBWU, upper);
141 mtspr(SPRN_TBWL, lower);
142}
143
144/* Accessor functions for the decrementer register.
145 * The 4xx doesn't even have a decrementer. I tried to use the
146 * generic timer interrupt code, which seems OK, with the 4xx PIT
147 * in auto-reload mode. The problem is PIT stops counting when it
148 * hits zero. If it would wrap, we could use it just like a decrementer.
149 */
150static inline u64 get_dec(void)
151{
152#if defined(CONFIG_40x)
153 return (mfspr(SPRN_PIT));
154#else
155 return (mfspr(SPRN_DEC));
156#endif
157}
158
159/*
160 * Note: Book E and 4xx processors differ from other PowerPC processors
161 * in when the decrementer generates its interrupt: on the 1 to 0
162 * transition for Book E/4xx, but on the 0 to -1 transition for others.
163 */
164static inline void set_dec(u64 val)
165{
166#if defined(CONFIG_40x)
167 mtspr(SPRN_PIT, (u32) val);
168#else
169#ifndef CONFIG_BOOKE
170 --val;
171#endif
172 mtspr(SPRN_DEC, val);
173#endif /* not 40x */
174}
175
176static inline unsigned long tb_ticks_since(unsigned long tstamp)
177{
178 if (__USE_RTC()) {
179 int delta = get_rtcl() - (unsigned int) tstamp;
180 return delta < 0 ? delta + 1000000000 : delta;
181 }
182 return get_tbl() - tstamp;
183}
184
185#define mulhwu(x,y) \
186({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
187
188#ifdef CONFIG_PPC64
189#define mulhdu(x,y) \
190({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
191#else
192extern u64 mulhdu(u64, u64);
193#endif
194
195extern void div128_by_32(u64 dividend_high, u64 dividend_low,
196 unsigned divisor, struct div_result *dr);
197
198extern void secondary_cpu_time_init(void);
199extern void __init time_init(void);
200
201DECLARE_PER_CPU(u64, decrementers_next_tb);
202
203/* Convert timebase ticks to nanoseconds */
204unsigned long long tb_to_ns(unsigned long long tb_ticks);
205
206#endif /* __KERNEL__ */
207#endif /* __POWERPC_TIME_H */