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/init.h> 21 22 #include <asm/gt64120.h> 23 #include <asm/i8253.h> 24 #include <asm/time.h> 25 26 #define GT641XX_BASE_CLOCK 50000000 /* 50MHz */ 27 28 void __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 } 55