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Viewing changes to roms/u-boot/arch/blackfin/include/asm/delay.h

  • Committer: Phil Dennis-Jordan
  • Date: 2017-07-21 08:03:43 UTC
  • mfrom: (1.1.1)
  • Revision ID: phil@philjordan.eu-20170721080343-2yr2vdj7713czahv
New upstream release 2.9.0.

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roms/u-boot/arch/blackfin/include/asm/delay.h
 
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/*
 
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 * U-boot - delay.h Routines for introducing delays
 
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 *
 
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 * Copyright (c) 2005-2007 Analog Devices Inc.
 
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 *
 
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 * SPDX-License-Identifier:     GPL-2.0+
 
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 */
 
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#ifndef _BLACKFIN_DELAY_H
 
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#define _BLACKFIN_DELAY_H
 
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/*
 
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 * Changes made by akbar.hussain@Lineo.com, for BLACKFIN
 
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 * Copyright (C) 1994 Hamish Macdonald
 
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 *
 
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 * Delay routines, using a pre-computed "loops_per_second" value.
 
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 */
 
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extern __inline__ void __delay(unsigned long loops)
 
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{
 
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        __asm__ __volatile__("1:\t%0 += -1;\n\t"
 
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                             "cc = %0 == 0;\n\t"
 
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                             "if ! cc jump 1b;\n":"=d"(loops)
 
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                             :"0"(loops));
 
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}
 
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/*
 
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 * Use only for very small delays ( < 1 msec).  Should probably use a
 
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 * lookup table, really, as the multiplications take much too long with
 
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 * short delays.  This is a "reasonable" implementation, though (and the
 
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 * first constant multiplications gets optimized away if the delay is
 
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 * a constant)
 
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 */
 
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extern __inline__ void __udelay(unsigned long usecs)
 
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{
 
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        __delay(usecs);
 
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}
 
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#endif