linux/linux-5.4.31/arch/mips/cobalt/time.c

42 lines
791 B
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Cobalt time initialization.
*
* Copyright (C) 2007 Yoichi Yuasa <yuasa@linux-mips.org>
*/
#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);
}