1 /* 2 * SH-Mobile Timer 3 * 4 * Copyright (C) 2010 Magnus Damm 5 * Copyright (C) 2002 - 2009 Paul Mundt 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; version 2 of the License. 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 St, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 */ 21 #include <linux/platform_device.h> 22 #include <linux/clocksource.h> 23 #include <linux/delay.h> 24 25 void __init shmobile_setup_delay(unsigned int max_cpu_core_mhz, 26 unsigned int mult, unsigned int div) 27 { 28 /* calculate a worst-case loops-per-jiffy value 29 * based on maximum cpu core mhz setting and the 30 * __delay() implementation in arch/arm/lib/delay.S 31 * 32 * this will result in a longer delay than expected 33 * when the cpu core runs on lower frequencies. 34 */ 35 36 unsigned int value = (1000000 * mult) / (HZ * div); 37 38 if (!preset_lpj) 39 preset_lpj = max_cpu_core_mhz * value; 40 } 41 42 static void __init shmobile_late_time_init(void) 43 { 44 /* 45 * Make sure all compiled-in early timers register themselves. 46 * 47 * Run probe() for two "earlytimer" devices, these will be the 48 * clockevents and clocksource devices respectively. In the event 49 * that only a clockevents device is available, we -ENODEV on the 50 * clocksource and the jiffies clocksource is used transparently 51 * instead. No error handling is necessary here. 52 */ 53 early_platform_driver_register_all("earlytimer"); 54 early_platform_driver_probe("earlytimer", 2, 0); 55 } 56 57 void __init shmobile_earlytimer_init(void) 58 { 59 late_time_init = shmobile_late_time_init; 60 } 61 62