| /* |
| * 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 |