/* * 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); }