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Diffstat (limited to 'kernel/arch/mips/cobalt/time.c')
-rw-r--r-- | kernel/arch/mips/cobalt/time.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/kernel/arch/mips/cobalt/time.c b/kernel/arch/mips/cobalt/time.c new file mode 100644 index 000000000..3bff3b820 --- /dev/null +++ b/kernel/arch/mips/cobalt/time.c @@ -0,0 +1,54 @@ +/* + * 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); +} |