tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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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/config.h>
18#include <linux/types.h>
19#include <linux/percpu.h>
20
21#include <asm/processor.h>
22#ifdef CONFIG_PPC64
23#include <asm/paca.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);
44
45/* Some sane defaults: 125 MHz timebase, 1GHz processor */
46extern unsigned long ppc_proc_freq;
47#define DEFAULT_PROC_FREQ (DEFAULT_TB_FREQ * 8)
48extern unsigned long ppc_tb_freq;
49#define DEFAULT_TB_FREQ 125000000UL
50
51/*
52 * By putting all of this stuff into a single struct we
53 * reduce the number of cache lines touched by do_gettimeofday.
54 * Both by collecting all of the data in one cache line and
55 * by touching only one TOC entry on ppc64.
56 */
57struct gettimeofday_vars {
58 u64 tb_to_xs;
59 u64 stamp_xsec;
60 u64 tb_orig_stamp;
61};
62
63struct gettimeofday_struct {
64 unsigned long tb_ticks_per_sec;
65 struct gettimeofday_vars vars[2];
66 struct gettimeofday_vars * volatile varp;
67 unsigned var_idx;
68 unsigned tb_to_us;
69};
70
71struct div_result {
72 u64 result_high;
73 u64 result_low;
74};
75
76/* Accessor functions for the timebase (RTC on 601) registers. */
77/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
78#ifdef CONFIG_6xx
79#define __USE_RTC() (!cpu_has_feature(CPU_FTR_USE_TB))
80#else
81#define __USE_RTC() 0
82#endif
83
84/* On ppc64 this gets us the whole timebase; on ppc32 just the lower half */
85static inline unsigned long get_tbl(void)
86{
87 unsigned long tbl;
88
89#if defined(CONFIG_403GCX)
90 asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
91#else
92 asm volatile("mftb %0" : "=r" (tbl));
93#endif
94 return tbl;
95}
96
97static inline unsigned int get_tbu(void)
98{
99 unsigned int tbu;
100
101#if defined(CONFIG_403GCX)
102 asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
103#else
104 asm volatile("mftbu %0" : "=r" (tbu));
105#endif
106 return tbu;
107}
108
109static inline unsigned int get_rtcl(void)
110{
111 unsigned int rtcl;
112
113 asm volatile("mfrtcl %0" : "=r" (rtcl));
114 return rtcl;
115}
116
117static inline u64 get_rtc(void)
118{
119 unsigned int hi, lo, hi2;
120
121 do {
122 asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
123 : "=r" (hi), "=r" (lo), "=r" (hi2));
124 } while (hi2 != hi);
125 return (u64)hi * 1000000000 + lo;
126}
127
128#ifdef CONFIG_PPC64
129static inline u64 get_tb(void)
130{
131 return mftb();
132}
133#else
134static inline u64 get_tb(void)
135{
136 unsigned int tbhi, tblo, tbhi2;
137
138 do {
139 tbhi = get_tbu();
140 tblo = get_tbl();
141 tbhi2 = get_tbu();
142 } while (tbhi != tbhi2);
143
144 return ((u64)tbhi << 32) | tblo;
145}
146#endif
147
148static inline void set_tb(unsigned int upper, unsigned int lower)
149{
150 mtspr(SPRN_TBWL, 0);
151 mtspr(SPRN_TBWU, upper);
152 mtspr(SPRN_TBWL, lower);
153}
154
155/* Accessor functions for the decrementer register.
156 * The 4xx doesn't even have a decrementer. I tried to use the
157 * generic timer interrupt code, which seems OK, with the 4xx PIT
158 * in auto-reload mode. The problem is PIT stops counting when it
159 * hits zero. If it would wrap, we could use it just like a decrementer.
160 */
161static inline unsigned int get_dec(void)
162{
163#if defined(CONFIG_40x)
164 return (mfspr(SPRN_PIT));
165#else
166 return (mfspr(SPRN_DEC));
167#endif
168}
169
170static inline void set_dec(int val)
171{
172#if defined(CONFIG_40x)
173 return; /* Have to let it auto-reload */
174#elif defined(CONFIG_8xx_CPU6)
175 set_dec_cpu6(val);
176#else
177#ifdef CONFIG_PPC_ISERIES
178 struct paca_struct *lpaca = get_paca();
179 int cur_dec;
180
181 if (lpaca->lppaca.shared_proc) {
182 lpaca->lppaca.virtual_decr = val;
183 cur_dec = get_dec();
184 if (cur_dec > val)
185 HvCall_setVirtualDecr();
186 } else
187#endif
188 mtspr(SPRN_DEC, val);
189#endif /* not 40x or 8xx_CPU6 */
190}
191
192static inline unsigned long tb_ticks_since(unsigned long tstamp)
193{
194 if (__USE_RTC()) {
195 int delta = get_rtcl() - (unsigned int) tstamp;
196 return delta < 0 ? delta + 1000000000 : delta;
197 }
198 return get_tbl() - tstamp;
199}
200
201#define mulhwu(x,y) \
202({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
203
204#ifdef CONFIG_PPC64
205#define mulhdu(x,y) \
206({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
207#else
208extern u64 mulhdu(u64, u64);
209#endif
210
211extern void smp_space_timers(unsigned int);
212
213extern unsigned mulhwu_scale_factor(unsigned, unsigned);
214extern void div128_by_32(u64 dividend_high, u64 dividend_low,
215 unsigned divisor, struct div_result *dr);
216
217/* Used to store Processor Utilization register (purr) values */
218
219struct cpu_usage {
220 u64 current_tb; /* Holds the current purr register values */
221};
222
223DECLARE_PER_CPU(struct cpu_usage, cpu_usage_array);
224
225#endif /* __KERNEL__ */
226#endif /* __PPC64_TIME_H */