cregit-Linux how code gets into the kernel

Release 4.14 arch/frv/include/asm/delay.h

/* delay.h: FRV delay code
 *
 * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * 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.
 */

#ifndef _ASM_DELAY_H

#define _ASM_DELAY_H

#include <asm/param.h>
#include <asm/timer-regs.h>

/*
 * delay loop - runs at __core_clock_speed_HZ / 2 [there are 2 insns in the loop]
 */
extern unsigned long __delay_loops_MHz;


static inline void __delay(unsigned long loops) { asm volatile("1: subicc %0,#1,%0,icc0 \n" " bnc icc0,#2,1b \n" : "=r" (loops) : "0" (loops) : "icc0" ); }

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David Howells14100.00%1100.00%
Total14100.00%1100.00%

/* * Use only for very small delays ( < 1 msec). Should probably use a * lookup table, really, as the multiplications take much too long with * short delays. This is a "reasonable" implementation, though (and the * first constant multiplications gets optimized away if the delay is * a constant) */ extern unsigned long loops_per_jiffy;
static inline void udelay(unsigned long usecs) { __delay(usecs * __delay_loops_MHz); }

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PersonTokensPropCommitsCommitProp
David Howells18100.00%1100.00%
Total18100.00%1100.00%

#define ndelay(n) udelay((n) * 5) #endif /* _ASM_DELAY_H */

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PersonTokensPropCommitsCommitProp
David Howells67100.00%1100.00%
Total67100.00%1100.00%
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