blob: 1e9278996e54d2f43589106e9a52c48f3349ef24 [file] [log] [blame]
wdenkc0218802003-03-27 12:09:35 +00001/*
2 * (C) Copyright 2003
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 *
5 * See file CREDITS for list of people who contributed to this
6 * project.
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21 * MA 02111-1307 USA
22 */
23
24#include <common.h>
Shinya Kuribayashic7e38e42008-06-05 22:28:59 +090025#include <asm/mipsregs.h>
wdenkc0218802003-03-27 12:09:35 +000026
Shinya Kuribayashia55d4812008-06-05 22:29:00 +090027static unsigned long timestamp;
28
29/* how many counter cycles in a jiffy */
30#define CYCLES_PER_JIFFY (CFG_MIPS_TIMER_FREQ + CFG_HZ / 2) / CFG_HZ
31
wdenkc0218802003-03-27 12:09:35 +000032/*
33 * timer without interrupts
34 */
35
36int timer_init(void)
37{
Shinya Kuribayashia55d4812008-06-05 22:29:00 +090038 /* Set up the timer for the first expiration. */
39 timestamp = 0;
40 write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
wdenkc0218802003-03-27 12:09:35 +000041
42 return 0;
43}
44
45void reset_timer(void)
46{
Shinya Kuribayashia55d4812008-06-05 22:29:00 +090047 timestamp = 0;
48 write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
wdenkc0218802003-03-27 12:09:35 +000049}
50
51ulong get_timer(ulong base)
52{
Shinya Kuribayashia55d4812008-06-05 22:29:00 +090053 unsigned int count;
54 unsigned int expirelo = read_c0_compare();
55
56 /* Check to see if we have missed any timestamps. */
57 count = read_c0_count();
58 while ((count - expirelo) < 0x7fffffff) {
59 expirelo += CYCLES_PER_JIFFY;
60 timestamp++;
61 }
62 write_c0_compare(expirelo);
63
64 return (timestamp - base);
wdenkc0218802003-03-27 12:09:35 +000065}
66
67void set_timer(ulong t)
68{
Shinya Kuribayashia55d4812008-06-05 22:29:00 +090069 timestamp = t;
70 write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
wdenkc0218802003-03-27 12:09:35 +000071}
72
Shinya Kuribayashi199e4f62008-06-05 22:29:00 +090073void udelay(unsigned long usec)
wdenkc0218802003-03-27 12:09:35 +000074{
Shinya Kuribayashi199e4f62008-06-05 22:29:00 +090075 unsigned int tmo;
wdenkc0218802003-03-27 12:09:35 +000076
Shinya Kuribayashi199e4f62008-06-05 22:29:00 +090077 tmo = read_c0_count() + (usec * (CFG_MIPS_TIMER_FREQ / 1000000));
78 while ((tmo - read_c0_count()) < 0x7fffffff)
wdenkc0218802003-03-27 12:09:35 +000079 /*NOP*/;
80}
81
82/*
83 * This function is derived from PowerPC code (read timebase as long long).
84 * On MIPS it just returns the timer value.
85 */
86unsigned long long get_ticks(void)
87{
Shinya Kuribayashia55d4812008-06-05 22:29:00 +090088 return get_timer(0);
wdenkc0218802003-03-27 12:09:35 +000089}
90
91/*
92 * This function is derived from PowerPC code (timebase clock frequency).
93 * On MIPS it returns the number of timer ticks per second.
94 */
95ulong get_tbclk(void)
96{
97 return CFG_HZ;
98}