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Based on 1 normalized pattern(s): 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 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 see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
59 lines
1.3 KiB
C
59 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Delay loops based on the OpenRISC implementation.
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*
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* Copyright (C) 2012 ARM Limited
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*
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* Author: Will Deacon <will.deacon@arm.com>
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*/
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#include <linux/delay.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/timex.h>
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#include <clocksource/arm_arch_timer.h>
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#define USECS_TO_CYCLES(time_usecs) \
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xloops_to_cycles((time_usecs) * 0x10C7UL)
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static inline unsigned long xloops_to_cycles(unsigned long xloops)
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{
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return (xloops * loops_per_jiffy * HZ) >> 32;
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}
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void __delay(unsigned long cycles)
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{
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cycles_t start = get_cycles();
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if (arch_timer_evtstrm_available()) {
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const cycles_t timer_evt_period =
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USECS_TO_CYCLES(ARCH_TIMER_EVT_STREAM_PERIOD_US);
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while ((get_cycles() - start + timer_evt_period) < cycles)
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wfe();
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}
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while ((get_cycles() - start) < cycles)
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cpu_relax();
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}
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EXPORT_SYMBOL(__delay);
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inline void __const_udelay(unsigned long xloops)
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{
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__delay(xloops_to_cycles(xloops));
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}
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EXPORT_SYMBOL(__const_udelay);
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void __udelay(unsigned long usecs)
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{
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__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
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}
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EXPORT_SYMBOL(__udelay);
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void __ndelay(unsigned long nsecs)
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{
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__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
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}
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EXPORT_SYMBOL(__ndelay);
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