/* * U-boot - delay.h Routines for introducing delays * * Copyright (c) 2005-2007 Analog Devices Inc. * * 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., 51 Franklin St, Fifth Floor, Boston, * MA 02110-1301 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