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/*
* U-boot - delay.h Routines for introducing delays
*
* Copyright (c) 2005 blackfin.uclinux.org
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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.
*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#ifndef _BLACKFIN_DELAY_H
#define _BLACKFIN_DELAY_H
/*
* Changes made by akbar.hussain@Lineo.com, for BLACKFIN
* Copyright (C) 1994 Hamish Macdonald
*
* Delay routines, using a pre-computed "loops_per_second" value.
*/
extern __inline__ void __delay(unsigned long loops)
{
__asm__ __volatile__("1:\t%0 += -1;\n\t"
"cc = %0 == 0;\n\t"
"if ! cc jump 1b;\n":"=d"(loops)
:"0"(loops));
}
/*
* 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 __inline__ void udelay(unsigned long usecs)
{
__delay(usecs);
}
#endif
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