mirror of
https://github.com/AsahiLinux/u-boot
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56 lines
1.7 KiB
C
56 lines
1.7 KiB
C
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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 blackfin.uclinux.org
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*
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* See file CREDITS for list of people who contributed to this
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* project.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
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* MA 02111-1307 USA
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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
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