aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/include/asm/time.h
blob: 54f4ec1f9fab81a41b7861dbcbdf3d757862881b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Common time prototypes and such for all ppc machines.
 *
 * Written by Cort Dougan (cort@cs.nmt.edu) to merge
 * Paul Mackerras' version and mine for PReP and Pmac.
 */

#ifndef __POWERPC_TIME_H
#define __POWERPC_TIME_H

#ifdef __KERNEL__
#include <linux/types.h>
#include <linux/percpu.h>

#include <asm/processor.h>
#include <asm/cpu_has_feature.h>

/* time.c */
extern unsigned long tb_ticks_per_jiffy;
extern unsigned long tb_ticks_per_usec;
extern unsigned long tb_ticks_per_sec;
extern struct clock_event_device decrementer_clockevent;


extern void generic_calibrate_decr(void);
extern void hdec_interrupt(struct pt_regs *regs);

/* Some sane defaults: 125 MHz timebase, 1GHz processor */
extern unsigned long ppc_proc_freq;
#define DEFAULT_PROC_FREQ	(DEFAULT_TB_FREQ * 8)
extern unsigned long ppc_tb_freq;
#define DEFAULT_TB_FREQ		125000000UL

extern bool tb_invalid;

struct div_result {
	u64 result_high;
	u64 result_low;
};

/* Accessor functions for the timebase (RTC on 601) registers. */
/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
#ifdef CONFIG_PPC_BOOK3S_32
#define __USE_RTC()	(cpu_has_feature(CPU_FTR_USE_RTC))
#else
#define __USE_RTC()	0
#endif

#ifdef CONFIG_PPC64

/* For compatibility, get_tbl() is defined as get_tb() on ppc64 */
#define get_tbl		get_tb

#else

static inline unsigned long get_tbl(void)
{
#if defined(CONFIG_403GCX)
	unsigned long tbl;
	asm volatile("mfspr %0, 0x3dd" : "=r" (tbl));
	return tbl;
#else
	return mftbl();
#endif
}

static inline unsigned int get_tbu(void)
{
#ifdef CONFIG_403GCX
	unsigned int tbu;
	asm volatile("mfspr %0, 0x3dc" : "=r" (tbu));
	return tbu;
#else
	return mftbu();
#endif
}
#endif /* !CONFIG_PPC64 */

static inline unsigned int get_rtcl(void)
{
	unsigned int rtcl;

	asm volatile("mfrtcl %0" : "=r" (rtcl));
	return rtcl;
}

static inline u64 get_rtc(void)
{
	unsigned int hi, lo, hi2;

	do {
		asm volatile("mfrtcu %0; mfrtcl %1; mfrtcu %2"
			     : "=r" (hi), "=r" (lo), "=r" (hi2));
	} while (hi2 != hi);
	return (u64)hi * 1000000000 + lo;
}

static inline u64 get_vtb(void)
{
#ifdef CONFIG_PPC_BOOK3S_64
	if (cpu_has_feature(CPU_FTR_ARCH_207S))
		return mfspr(SPRN_VTB);
#endif
	return 0;
}

#ifdef CONFIG_PPC64
static inline u64 get_tb(void)
{
	return mftb();
}
#else /* CONFIG_PPC64 */
static inline u64 get_tb(void)
{
	unsigned int tbhi, tblo, tbhi2;

	do {
		tbhi = get_tbu();
		tblo = get_tbl();
		tbhi2 = get_tbu();
	} while (tbhi != tbhi2);

	return ((u64)tbhi << 32) | tblo;
}
#endif /* !CONFIG_PPC64 */

static inline u64 get_tb_or_rtc(void)
{
	return __USE_RTC() ? get_rtc() : get_tb();
}

static inline void set_tb(unsigned int upper, unsigned int lower)
{
	mtspr(SPRN_TBWL, 0);
	mtspr(SPRN_TBWU, upper);
	mtspr(SPRN_TBWL, lower);
}

/* Accessor functions for the decrementer register.
 * The 4xx doesn't even have a decrementer.  I tried to use the
 * generic timer interrupt code, which seems OK, with the 4xx PIT
 * in auto-reload mode.  The problem is PIT stops counting when it
 * hits zero.  If it would wrap, we could use it just like a decrementer.
 */
static inline u64 get_dec(void)
{
#if defined(CONFIG_40x)
	return (mfspr(SPRN_PIT));
#else
	return (mfspr(SPRN_DEC));
#endif
}

/*
 * Note: Book E and 4xx processors differ from other PowerPC processors
 * in when the decrementer generates its interrupt: on the 1 to 0
 * transition for Book E/4xx, but on the 0 to -1 transition for others.
 */
static inline void set_dec(u64 val)
{
#if defined(CONFIG_40x)
	mtspr(SPRN_PIT, (u32) val);
#else
#ifndef CONFIG_BOOKE
	--val;
#endif
	mtspr(SPRN_DEC, val);
#endif /* not 40x */
}

static inline unsigned long tb_ticks_since(unsigned long tstamp)
{
	if (__USE_RTC()) {
		int delta = get_rtcl() - (unsigned int) tstamp;
		return delta < 0 ? delta + 1000000000 : delta;
	}
	return get_tbl() - tstamp;
}

#define mulhwu(x,y) \
({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})

#ifdef CONFIG_PPC64
#define mulhdu(x,y) \
({unsigned long z; asm ("mulhdu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})
#else
extern u64 mulhdu(u64, u64);
#endif

extern void div128_by_32(u64 dividend_high, u64 dividend_low,
			 unsigned divisor, struct div_result *dr);

extern void secondary_cpu_time_init(void);
extern void __init time_init(void);

DECLARE_PER_CPU(u64, decrementers_next_tb);

/* Convert timebase ticks to nanoseconds */
unsigned long long tb_to_ns(unsigned long long tb_ticks);

#endif /* __KERNEL__ */
#endif /* __POWERPC_TIME_H */