/* * OpenRISC Linux * * Linux architectural port borrowing liberally from similar works of * others. All original copyrights apply as per the original source * declaration. * * Modifications for the OpenRISC architecture: * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 2 as published by the Free Software Foundation * * Precise Delay Loops */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <asm/delay.h> #include <asm/timex.h> #include <asm/processor.h> int __devinit read_current_timer(unsigned long *timer_value) { *timer_value = mfspr(SPR_TTCR); return 0; } void __delay(unsigned long cycles) { cycles_t target = get_cycles() + cycles; while (get_cycles() < target) cpu_relax(); } EXPORT_SYMBOL(__delay); inline void __const_udelay(unsigned long xloops) { unsigned long long loops; loops = xloops * loops_per_jiffy * HZ; __delay(loops >> 32); } EXPORT_SYMBOL(__const_udelay); void __udelay(unsigned long usecs) { __const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */ } EXPORT_SYMBOL(__udelay); void __ndelay(unsigned long nsecs) { __const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */ } EXPORT_SYMBOL(__ndelay);