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
|
/*
* (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
* Gary Jennejohn, DENX Software Engineering, <gj@denx.de>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <arm920t.h>
#include <lh7a40x.h>
static ulong timer_load_val = 0;
/* macro to read the 16 bit timer */
static inline ulong READ_TIMER(void)
{
lh7a40x_timers_t* timers = LH7A40X_TIMERS_PTR;
lh7a40x_timer_t* timer = &timers->timer1;
return (timer->value & 0x0000ffff);
}
static ulong timestamp;
static ulong lastdec;
int interrupt_init (void)
{
lh7a40x_timers_t* timers = LH7A40X_TIMERS_PTR;
lh7a40x_timer_t* timer = &timers->timer1;
/* a periodic timer using the 508kHz source */
timer->control = (TIMER_PER | TIMER_CLK508K);
if (timer_load_val == 0) {
/*
* 10ms period with 508.469kHz clock = 5084
*/
timer_load_val = CFG_HZ/100;
}
/* load value for 10 ms timeout */
lastdec = timer->load = timer_load_val;
/* auto load, start timer */
timer->control = timer->control | TIMER_EN;
timestamp = 0;
return (0);
}
/*
* timer without interrupts
*/
void reset_timer (void)
{
reset_timer_masked ();
}
ulong get_timer (ulong base)
{
return (get_timer_masked() - base);
}
void set_timer (ulong t)
{
timestamp = t;
}
void udelay (unsigned long usec)
{
ulong tmo,tmp;
/* normalize */
if (usec >= 1000) {
tmo = usec / 1000;
tmo *= CFG_HZ;
tmo /= 1000;
}
else {
if (usec > 1) {
tmo = usec * CFG_HZ;
tmo /= (1000*1000);
}
else
tmo = 1;
}
/* check for rollover during this delay */
tmp = get_timer (0);
if ((tmp + tmo) < tmp )
reset_timer_masked(); /* timer would roll over */
else
tmo += tmp;
while (get_timer_masked () < tmo);
}
void reset_timer_masked (void)
{
/* reset time */
lastdec = READ_TIMER();
timestamp = 0;
}
ulong get_timer_masked (void)
{
ulong now = READ_TIMER();
if (lastdec >= now) {
/* normal mode */
timestamp += (lastdec - now);
} else {
/* we have an overflow ... */
timestamp += ((lastdec + timer_load_val) - now);
}
lastdec = now;
return timestamp;
}
void udelay_masked (unsigned long usec)
{
ulong tmo;
ulong endtime;
signed long diff;
/* normalize */
if (usec >= 1000) {
tmo = usec / 1000;
tmo *= CFG_HZ;
tmo /= 1000;
} else {
if (usec > 1) {
tmo = usec * CFG_HZ;
tmo /= (1000*1000);
} else {
tmo = 1;
}
}
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)
{
ulong tbclk;
tbclk = timer_load_val * 100;
return tbclk;
}
|
