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/*
* Cobalt time initialization.
*
* Copyright (C) 2007 Yoichi Yuasa <yuasa@linux-mips.org>
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/i8253.h>
#include <linux/init.h>
#include <asm/gt64120.h>
#include <asm/time.h>
#define GT641XX_BASE_CLOCK 50000000 /* 50MHz */
void __init plat_time_init(void)
{
u32 start, end;
int i = HZ / 10;
setup_pit_timer();
gt641xx_set_base_clock(GT641XX_BASE_CLOCK);
/*
* MIPS counter frequency is measured during a 100msec interval
* using GT64111 timer0.
*/
while (!gt641xx_timer0_state())
;
start = read_c0_count();
while (i--)
while (!gt641xx_timer0_state())
;
end = read_c0_count();
mips_hpt_frequency = (end - start) * 10;
printk(KERN_INFO "MIPS counter frequency %dHz\n", mips_hpt_frequency);
}
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