1/*
 2 *  Cobalt time initialization.
 3 *
 4 *  Copyright (C) 2007  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/i8253.h>
21#include <linux/init.h>
22
23#include <asm/gt64120.h>
24#include <asm/time.h>
25
26#define GT641XX_BASE_CLOCK	50000000	/* 50MHz */
27
28void __init plat_time_init(void)
29{
30	u32 start, end;
31	int i = HZ / 10;
32
33	setup_pit_timer();
34
35	gt641xx_set_base_clock(GT641XX_BASE_CLOCK);
36
37	/*
38	 * MIPS counter frequency is measured during a 100msec interval
39	 * using GT64111 timer0.
40	 */
41	while (!gt641xx_timer0_state())
42		;
43
44	start = read_c0_count();
45
46	while (i--)
47		while (!gt641xx_timer0_state())
48			;
49
50	end = read_c0_count();
51
52	mips_hpt_frequency = (end - start) * 10;
53	printk(KERN_INFO "MIPS counter frequency %dHz\n", mips_hpt_frequency);
54}

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2/*
 3 *  Cobalt time initialization.
 4 *
 5 *  Copyright (C) 2007  Yoichi Yuasa <yuasa@linux-mips.org>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 6 */
 7#include <linux/i8253.h>
 8#include <linux/init.h>
 9
10#include <asm/gt64120.h>
11#include <asm/time.h>
12
13#define GT641XX_BASE_CLOCK	50000000	/* 50MHz */
14
15void __init plat_time_init(void)
16{
17	u32 start, end;
18	int i = HZ / 10;
19
20	setup_pit_timer();
21
22	gt641xx_set_base_clock(GT641XX_BASE_CLOCK);
23
24	/*
25	 * MIPS counter frequency is measured during a 100msec interval
26	 * using GT64111 timer0.
27	 */
28	while (!gt641xx_timer0_state())
29		;
30
31	start = read_c0_count();
32
33	while (i--)
34		while (!gt641xx_timer0_state())
35			;
36
37	end = read_c0_count();
38
39	mips_hpt_frequency = (end - start) * 10;
40	printk(KERN_INFO "MIPS counter frequency %dHz\n", mips_hpt_frequency);
41}