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
|
/*
* (C) Copyright 2003
* Texas Instruments <www.ti.com>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* (C) Copyright 2002-2004
* Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
*
* (C) Copyright 2004
* Philippe Robin, ARM Ltd. <philippe.robin@arm.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#define TIMER_CLOCK (CONFIG_SYS_CLK_FREQ / (2 << CONFIG_SYS_PTV))
#define TIMER_LOAD_VAL 0xffffffff
/* macro to read the 32 bit timer */
#define READ_TIMER readl(CONFIG_SYS_TIMERBASE+8) \
/ (TIMER_CLOCK / CONFIG_SYS_HZ)
DECLARE_GLOBAL_DATA_PTR;
#define timestamp gd->arch.tbl
#define lastdec gd->arch.lastinc
int timer_init (void)
{
int32_t val;
/* Start the decrementer ticking down from 0xffffffff */
*((int32_t *) (CONFIG_SYS_TIMERBASE + LOAD_TIM)) = TIMER_LOAD_VAL;
val = MPUTIM_ST | MPUTIM_AR | MPUTIM_CLOCK_ENABLE | (CONFIG_SYS_PTV << MPUTIM_PTV_BIT);
*((int32_t *) (CONFIG_SYS_TIMERBASE + CNTL_TIMER)) = val;
/* init the timestamp and lastdec value */
reset_timer_masked();
return 0;
}
/*
* timer without interrupts
*/
ulong get_timer (ulong base)
{
return get_timer_masked () - base;
}
/* delay x useconds AND preserve advance timestamp value */
void __udelay (unsigned long usec)
{
ulong tmo, tmp;
if(usec >= 1000){ /* if "big" number, spread normalization to seconds */
tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
tmo *= CONFIG_SYS_HZ; /* find number of "ticks" to wait to achieve target */
tmo /= 1000; /* finish normalize. */
}else{ /* else small number, don't kill it prior to HZ multiply */
tmo = usec * CONFIG_SYS_HZ;
tmo /= (1000*1000);
}
tmp = get_timer (0); /* get current timestamp */
if( (tmo + tmp + 1) < tmp ) /* if setting this fordward will roll time stamp */
reset_timer_masked (); /* reset "advancing" timestamp to 0, set lastdec value */
else
tmo += tmp; /* else, set advancing stamp wake up time */
while (get_timer_masked () < tmo)/* loop till event */
/*NOP*/;
}
void reset_timer_masked (void)
{
/* reset time */
lastdec = READ_TIMER; /* capure current decrementer value time */
timestamp = 0; /* start "advancing" time stamp from 0 */
}
ulong get_timer_masked (void)
{
ulong now = READ_TIMER; /* current tick value */
if (lastdec >= now) { /* normal mode (non roll) */
/* normal mode */
timestamp += lastdec - now; /* move stamp fordward with absoulte diff ticks */
} else { /* we have overflow of the count down timer */
/* nts = ts + ld + (TLV - now)
* ts=old stamp, ld=time that passed before passing through -1
* (TLV-now) amount of time after passing though -1
* nts = new "advancing time stamp"...it could also roll and cause problems.
*/
timestamp += lastdec + (TIMER_LOAD_VAL / (TIMER_CLOCK /
CONFIG_SYS_HZ)) - now;
}
lastdec = now;
return timestamp;
}
/* waits specified delay value and resets timestamp */
void udelay_masked (unsigned long usec)
{
ulong tmo;
ulong endtime;
signed long diff;
if (usec >= 1000) { /* if "big" number, spread normalization to seconds */
tmo = usec / 1000; /* start to normalize for usec to ticks per sec */
tmo *= CONFIG_SYS_HZ; /* find number of "ticks" to wait to achieve target */
tmo /= 1000; /* finish normalize. */
} else { /* else small number, don't kill it prior to HZ multiply */
tmo = usec * CONFIG_SYS_HZ;
tmo /= (1000*1000);
}
endtime = get_timer_masked () + tmo;
do {
ulong now = get_timer_masked ();
diff = endtime - now;
} while (diff >= 0);
}
/*
* This function is derived from PowerPC code (read timebase as long long).
* On ARM it just returns the timer value.
*/
unsigned long long get_ticks(void)
{
return get_timer(0);
}
/*
* This function is derived from PowerPC code (timebase clock frequency).
* On ARM it returns the number of timer ticks per second.
*/
ulong get_tbclk (void)
{
return CONFIG_SYS_HZ;
}
|
