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1/*
2 * DEC I/O ASIC's counter clocksource
3 *
4 * Copyright (C) 2008 Yoichi Yuasa <yuasa@linux-mips.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20#include <linux/clocksource.h>
21#include <linux/init.h>
22
23#include <asm/ds1287.h>
24#include <asm/time.h>
25#include <asm/dec/ioasic.h>
26#include <asm/dec/ioasic_addrs.h>
27
28static cycle_t dec_ioasic_hpt_read(struct clocksource *cs)
29{
30 return ioasic_read(IO_REG_FCTR);
31}
32
33static struct clocksource clocksource_dec = {
34 .name = "dec-ioasic",
35 .read = dec_ioasic_hpt_read,
36 .mask = CLOCKSOURCE_MASK(32),
37 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
38};
39
40void __init dec_ioasic_clocksource_init(void)
41{
42 unsigned int freq;
43 u32 start, end;
44 int i = HZ / 10;
45
46
47 while (!ds1287_timer_state())
48 ;
49
50 start = dec_ioasic_hpt_read(&clocksource_dec);
51
52 while (i--)
53 while (!ds1287_timer_state())
54 ;
55
56 end = dec_ioasic_hpt_read(&clocksource_dec);
57
58 freq = (end - start) * 10;
59 printk(KERN_INFO "I/O ASIC clock frequency %dHz\n", freq);
60
61 clocksource_dec.rating = 200 + freq / 10000000;
62 clocksource_register_hz(&clocksource_dec, freq);
63}
1/*
2 * DEC I/O ASIC's counter clocksource
3 *
4 * Copyright (C) 2008 Yoichi Yuasa <yuasa@linux-mips.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20#include <linux/clocksource.h>
21#include <linux/init.h>
22
23#include <asm/ds1287.h>
24#include <asm/time.h>
25#include <asm/dec/ioasic.h>
26#include <asm/dec/ioasic_addrs.h>
27
28static cycle_t dec_ioasic_hpt_read(struct clocksource *cs)
29{
30 return ioasic_read(IO_REG_FCTR);
31}
32
33static struct clocksource clocksource_dec = {
34 .name = "dec-ioasic",
35 .read = dec_ioasic_hpt_read,
36 .mask = CLOCKSOURCE_MASK(32),
37 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
38};
39
40void __init dec_ioasic_clocksource_init(void)
41{
42 unsigned int freq;
43 u32 start, end;
44 int i = HZ / 10;
45
46
47 while (!ds1287_timer_state())
48 ;
49
50 start = dec_ioasic_hpt_read(&clocksource_dec);
51
52 while (i--)
53 while (!ds1287_timer_state())
54 ;
55
56 end = dec_ioasic_hpt_read(&clocksource_dec);
57
58 freq = (end - start) * 10;
59 printk(KERN_INFO "I/O ASIC clock frequency %dHz\n", freq);
60
61 clocksource_dec.rating = 200 + freq / 10000000;
62 clocksource_register_hz(&clocksource_dec, freq);
63}