tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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
22/* time.c */
23extern unsigned long tb_ticks_per_jiffy;
24extern unsigned long tb_ticks_per_usec;
25extern unsigned long tb_ticks_per_sec;
26extern struct clock_event_device decrementer_clockevent;
27
28struct rtc_time;
29extern void to_tm(int tim, struct rtc_time * tm);
30extern void GregorianDay(struct rtc_time *tm);
31extern void tick_broadcast_ipi_handler(void);
32
33extern void generic_calibrate_decr(void);
34
35extern void set_dec_cpu6(unsigned int val);
36
37/* Some sane defaults: 125 MHz timebase, 1GHz processor */
38extern unsigned long ppc_proc_freq;
39#define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
40extern unsigned long ppc_tb_freq;
41#define DEFAULT_TB_FREQ 125000000UL
42
43struct div_result {
44 u64 result_high;
45 u64 result_low;
46};
47
48/* Accessor functions for the timebase (RTC on 601) registers. */
49/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
50#ifdef CONFIG_6xx
51#define __USE_RTC() (!cpu_has_feature(CPU_FTR_USE_TB))
52#else
53#define __USE_RTC() 0
54#endif
55
56#ifdef CONFIG_PPC64
57
58/* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
59#define get_tbl get_tb
60
61#else
62
63static inline unsigned long get_tbl(void)
64{
65#if defined(CONFIG_403GCX)
66 unsigned long tbl;
67 asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
68 return tbl;
69#else
70 return mftbl();
71#endif
72}
73
74static inline unsigned int get_tbu(void)
75{
76#ifdef CONFIG_403GCX
77 unsigned int tbu;
78 asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
79 return tbu;
80#else
81 return mftbu();
82#endif
83}
84#endif /* !CONFIG_PPC64 */
85
86static inline unsigned int get_rtcl(void)
87{
88 unsigned int rtcl;
89
90 asm volatile("mfrtcl %0" : "=r" (rtcl));
91 return rtcl;
92}
93
94static inline u64 get_rtc(void)
95{
96 unsigned int hi, lo, hi2;
97
98 do {
99 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
100 : "=r" (hi), "=r" (lo), "=r" (hi2));
101 } while (hi2 != hi);
102 return (u64)hi * 1000000000 + lo;
103}
104
105#ifdef CONFIG_PPC64
106static inline u64 get_tb(void)
107{
108 return mftb();
109}
110#else /* CONFIG_PPC64 */
111static inline u64 get_tb(void)
112{
113 unsigned int tbhi, tblo, tbhi2;
114
115 do {
116 tbhi = get_tbu();
117 tblo = get_tbl();
118 tbhi2 = get_tbu();
119 } while (tbhi != tbhi2);
120
121 return ((u64)tbhi << 32) | tblo;
122}
123#endif /* !CONFIG_PPC64 */
124
125static inline u64 get_tb_or_rtc(void)
126{
127 return __USE_RTC() ? get_rtc() : get_tb();
128}
129
130static inline void set_tb(unsigned int upper, unsigned int lower)
131{
132 mtspr(SPRN_TBWL, 0);
133 mtspr(SPRN_TBWU, upper);
134 mtspr(SPRN_TBWL, lower);
135}
136
137/* Accessor functions for the decrementer register.
138 * The 4xx doesn't even have a decrementer. I tried to use the
139 * generic timer interrupt code, which seems OK, with the 4xx PIT
140 * in auto-reload mode. The problem is PIT stops counting when it
141 * hits zero. If it would wrap, we could use it just like a decrementer.
142 */
143static inline unsigned int get_dec(void)
144{
145#if defined(CONFIG_40x)
146 return (mfspr(SPRN_PIT));
147#else
148 return (mfspr(SPRN_DEC));
149#endif
150}
151
152/*
153 * Note: Book E and 4xx processors differ from other PowerPC processors
154 * in when the decrementer generates its interrupt: on the 1 to 0
155 * transition for Book E/4xx, but on the 0 to -1 transition for others.
156 */
157static inline void set_dec(int val)
158{
159#if defined(CONFIG_40x)
160 mtspr(SPRN_PIT, val);
161#elif defined(CONFIG_8xx_CPU6)
162 set_dec_cpu6(val - 1);
163#else
164#ifndef CONFIG_BOOKE
165 --val;
166#endif
167 mtspr(SPRN_DEC, val);
168#endif /* not 40x or 8xx_CPU6 */
169}
170
171static inline unsigned long tb_ticks_since(unsigned long tstamp)
172{
173 if (__USE_RTC()) {
174 int delta = get_rtcl() - (unsigned int) tstamp;
175 return delta < 0 ? delta + 1000000000 : delta;
176 }
177 return get_tbl() - tstamp;
178}
179
180#define mulhwu(x,y) \
181({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
182
183#ifdef CONFIG_PPC64
184#define mulhdu(x,y) \
185({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
186#else
187extern u64 mulhdu(u64, u64);
188#endif
189
190extern void div128_by_32(u64 dividend_high, u64 dividend_low,
191 unsigned divisor, struct div_result *dr);
192
193/* Used to store Processor Utilization register (purr) values */
194
195struct cpu_usage {
196 u64 current_tb; /* Holds the current purr register values */
197};
198
199DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
200
201extern void secondary_cpu_time_init(void);
202
203DECLARE_PER_CPU(u64, decrementers_next_tb);
204
205#endif /* __KERNEL__ */
206#endif /* __POWERPC_TIME_H */