summaryrefslogtreecommitdiff
path: root/include/asm-ppc/time.h
blob: c86112323c9f097e3297d7dc74a51efeae76b4cb (plain)
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
/*
 * Common time prototypes and such for all ppc machines.
 *
 * Written by Cort Dougan (cort@fsmlabs.com) to merge
 * Paul Mackerras' version and mine for PReP and Pmac.
 */

#ifdef __KERNEL__
#ifndef __ASM_TIME_H__
#define __ASM_TIME_H__

#include <linux/config.h>
#include <linux/types.h>
#include <linux/rtc.h>
#include <linux/threads.h>

#include <asm/reg.h>

/* time.c */
extern unsigned tb_ticks_per_jiffy;
extern unsigned tb_to_us;
extern unsigned tb_last_stamp;
extern unsigned long disarm_decr[NR_CPUS];

extern void to_tm(int tim, struct rtc_time * tm);
extern time_t last_rtc_update;

extern void set_dec_cpu6(unsigned int val);

int via_calibrate_decr(void);

/* 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__ unsigned int get_dec(void)
{
#if defined(CONFIG_40x)
	return (mfspr(SPRN_PIT));
#else
	return (mfspr(SPRN_DEC));
#endif
}

static __inline__ void set_dec(unsigned int val)
{
#if defined(CONFIG_40x)
	return;		/* Have to let it auto-reload */
#elif defined(CONFIG_8xx_CPU6)
	set_dec_cpu6(val);
#else
	mtspr(SPRN_DEC, val);
#endif
}

/* Accessor functions for the timebase (RTC on 601) registers. */
/* If one day CONFIG_POWER is added just define __USE_RTC as 1 */
#ifdef CONFIG_6xx
extern __inline__ int __attribute_pure__ __USE_RTC(void) {
	return (mfspr(SPRN_PVR)>>16) == 1;
}
#else
#define __USE_RTC() 0
#endif

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

extern __inline__ unsigned long get_tbu(void) {
	unsigned long tbl;
#if defined(CONFIG_403GCX)
	asm volatile("mfspr %0, 0x3dc" : "=r" (tbl));
#else
	asm volatile("mftbu %0" : "=r" (tbl));
#endif
	return tbl;
}

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

extern __inline__ unsigned long get_rtcl(void) {
	unsigned long rtcl;
	asm volatile("mfrtcl %0" : "=r" (rtcl));
	return rtcl;
}

extern __inline__ unsigned long get_rtcu(void)
{
	unsigned long rtcu;
	asm volatile("mfrtcu %0" : "=r" (rtcu));
	return rtcu;
}

extern __inline__ unsigned get_native_tbl(void) {
	if (__USE_RTC())
		return get_rtcl();
	else
	  	return get_tbl();
}

/* On machines with RTC, this function can only be used safely
 * after the timestamp and for 1 second. It is only used by gettimeofday
 * however so it should not matter.
 */
extern __inline__ unsigned tb_ticks_since(unsigned tstamp) {
	if (__USE_RTC()) {
		int delta = get_rtcl() - tstamp;
		return delta<0 ? delta + 1000000000 : delta;
	} else {
        	return get_tbl() - tstamp;
	}
}

#if 0
extern __inline__ unsigned long get_bin_rtcl(void) {
      unsigned long rtcl, rtcu1, rtcu2;
      asm volatile("\
1:    mfrtcu  %0\n\
      mfrtcl  %1\n\
      mfrtcu  %2\n\
      cmpw    %0,%2\n\
      bne-    1b\n"
      : "=r" (rtcu1), "=r" (rtcl), "=r" (rtcu2)
      : : "cr0");
      return rtcu2*1000000000+rtcl;
}

extern __inline__ unsigned binary_tbl(void) {
      if (__USE_RTC())
              return get_bin_rtcl();
      else
              return get_tbl();
}
#endif

/* Use mulhwu to scale processor timebase to timeval */
/* Specifically, this computes (x * y) / 2^32.  -- paulus */
#define mulhwu(x,y) \
({unsigned z; asm ("mulhwu %0,%1,%2" : "=r" (z) : "r" (x), "r" (y)); z;})

unsigned mulhwu_scale_factor(unsigned, unsigned);

#define account_process_vtime(tsk)		do { } while (0)
#define calculate_steal_time()			do { } while (0)
#define snapshot_timebases()			do { } while (0)

#endif /* __ASM_TIME_H__ */
#endif /* __KERNEL__ */