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#ifdef CONFIG_PPC_ISERIES
22#include <asm/paca.h>
23#include <asm/firmware.h>
24#include <asm/iseries/hv_call.h>
25#endif
26
27/* time.c */
28extern unsigned long tb_ticks_per_jiffy;
29extern unsigned long tb_ticks_per_usec;
30extern unsigned long tb_ticks_per_sec;
31extern u64 tb_to_xs;
32extern unsigned tb_to_us;
33extern unsigned long tb_last_stamp;
34extern u64 tb_last_jiffy;
35
36DECLARE_PER_CPU(unsigned long, last_jiffy);
37
38struct rtc_time;
39extern void to_tm(int tim, struct rtc_time * tm);
40extern time_t last_rtc_update;
41
42extern void generic_calibrate_decr(void);
43extern void wakeup_decrementer(void);
44extern void snapshot_timebase(void);
45
46/* Some sane defaults: 125 MHz timebase, 1GHz processor */
47extern unsigned long ppc_proc_freq;
48#define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
49extern unsigned long ppc_tb_freq;
50#define DEFAULT_TB_FREQ 125000000UL
51
52/*
53 * By putting all of this stuff into a single struct we
54 * reduce the number of cache lines touched by do_gettimeofday.
55 * Both by collecting all of the data in one cache line and
56 * by touching only one TOC entry on ppc64.
57 */
58struct gettimeofday_vars {
59 u64 tb_to_xs;
60 u64 stamp_xsec;
61 u64 tb_orig_stamp;
62};
63
64struct gettimeofday_struct {
65 unsigned long tb_ticks_per_sec;
66 struct gettimeofday_vars vars[2];
67 struct gettimeofday_vars * volatile varp;
68 unsigned var_idx;
69 unsigned tb_to_us;
70};
71
72struct div_result {
73 u64 result_high;
74 u64 result_low;
75};
76
77/* Accessor functions for the timebase (RTC on 601) registers. */
78/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
79#ifdef CONFIG_6xx
80#define __USE_RTC() (!cpu_has_feature(CPU_FTR_USE_TB))
81#else
82#define __USE_RTC() 0
83#endif
84
85/* On ppc64 this gets us the whole timebase; on ppc32 just the lower half */
86static inline unsigned long get_tbl(void)
87{
88 unsigned long tbl;
89
90#if defined(CONFIG_403GCX)
91 asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
92#else
93 asm volatile("mftb %0" : "=r" (tbl));
94#endif
95 return tbl;
96}
97
98static inline unsigned int get_tbu(void)
99{
100 unsigned int tbu;
101
102#if defined(CONFIG_403GCX)
103 asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
104#else
105 asm volatile("mftbu %0" : "=r" (tbu));
106#endif
107 return tbu;
108}
109
110static inline unsigned int get_rtcl(void)
111{
112 unsigned int rtcl;
113
114 asm volatile("mfrtcl %0" : "=r" (rtcl));
115 return rtcl;
116}
117
118static inline u64 get_rtc(void)
119{
120 unsigned int hi, lo, hi2;
121
122 do {
123 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
124 : "=r" (hi), "=r" (lo), "=r" (hi2));
125 } while (hi2 != hi);
126 return (u64)hi * 1000000000 + lo;
127}
128
129#ifdef CONFIG_PPC64
130static inline u64 get_tb(void)
131{
132 return mftb();
133}
134#else
135static inline u64 get_tb(void)
136{
137 unsigned int tbhi, tblo, tbhi2;
138
139 do {
140 tbhi = get_tbu();
141 tblo = get_tbl();
142 tbhi2 = get_tbu();
143 } while (tbhi != tbhi2);
144
145 return ((u64)tbhi << 32) | tblo;
146}
147#endif
148
149static inline void set_tb(unsigned int upper, unsigned int lower)
150{
151 mtspr(SPRN_TBWL, 0);
152 mtspr(SPRN_TBWU, upper);
153 mtspr(SPRN_TBWL, lower);
154}
155
156/* Accessor functions for the decrementer register.
157 * The 4xx doesn't even have a decrementer. I tried to use the
158 * generic timer interrupt code, which seems OK, with the 4xx PIT
159 * in auto-reload mode. The problem is PIT stops counting when it
160 * hits zero. If it would wrap, we could use it just like a decrementer.
161 */
162static inline unsigned int get_dec(void)
163{
164#if defined(CONFIG_40x)
165 return (mfspr(SPRN_PIT));
166#else
167 return (mfspr(SPRN_DEC));
168#endif
169}
170
171static inline void set_dec(int val)
172{
173#if defined(CONFIG_40x)
174 return; /* Have to let it auto-reload */
175#elif defined(CONFIG_8xx_CPU6)
176 set_dec_cpu6(val);
177#else
178#ifdef CONFIG_PPC_ISERIES
179 int cur_dec;
180
181 if (firmware_has_feature(FW_FEATURE_ISERIES) &&
182 get_lppaca()->shared_proc) {
183 get_lppaca()->virtual_decr = val;
184 cur_dec = get_dec();
185 if (cur_dec > val)
186 HvCall_setVirtualDecr();
187 } else
188#endif
189 mtspr(SPRN_DEC, val);
190#endif /* not 40x or 8xx_CPU6 */
191}
192
193static inline unsigned long tb_ticks_since(unsigned long tstamp)
194{
195 if (__USE_RTC()) {
196 int delta = get_rtcl() - (unsigned int) tstamp;
197 return delta < 0 ? delta + 1000000000 : delta;
198 }
199 return get_tbl() - tstamp;
200}
201
202#define mulhwu(x,y) \
203({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
204
205#ifdef CONFIG_PPC64
206#define mulhdu(x,y) \
207({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
208#else
209extern u64 mulhdu(u64, u64);
210#endif
211
212extern void smp_space_timers(unsigned int);
213
214extern unsigned mulhwu_scale_factor(unsigned, unsigned);
215extern void div128_by_32(u64 dividend_high, u64 dividend_low,
216 unsigned divisor, struct div_result *dr);
217
218/* Used to store Processor Utilization register (purr) values */
219
220struct cpu_usage {
221 u64 current_tb; /* Holds the current purr register values */
222};
223
224DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
225
226#ifdef CONFIG_VIRT_CPU_ACCOUNTING
227extern void account_process_vtime(struct task_struct *tsk);
228#else
229#define account_process_vtime(tsk) do { } while (0)
230#endif
231
232#if defined(CONFIG_VIRT_CPU_ACCOUNTING) && defined(CONFIG_PPC_SPLPAR)
233extern void calculate_steal_time(void);
234extern void snapshot_timebases(void);
235#else
236#define calculate_steal_time() do { } while (0)
237#define snapshot_timebases() do { } while (0)
238#endif
239
240#endif /* __KERNEL__ */
241#endif /* __PPC64_TIME_H */