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Wolfgang Denk6cb142f2006-03-12 02:12:27 +01001/*
Bin Menga1875592016-02-05 19:30:11 -08002 * U-Boot - delay.h Routines for introducing delays
Wolfgang Denk6cb142f2006-03-12 02:12:27 +01003 *
Aubrey Li155fd762007-04-05 18:31:18 +08004 * Copyright (c) 2005-2007 Analog Devices Inc.
Wolfgang Denk6cb142f2006-03-12 02:12:27 +01005 *
Wolfgang Denk1a459662013-07-08 09:37:19 +02006 * SPDX-License-Identifier: GPL-2.0+
Wolfgang Denk6cb142f2006-03-12 02:12:27 +01007 */
8
9#ifndef _BLACKFIN_DELAY_H
10#define _BLACKFIN_DELAY_H
11
12/*
13 * Changes made by akbar.hussain@Lineo.com, for BLACKFIN
14 * Copyright (C) 1994 Hamish Macdonald
15 *
16 * Delay routines, using a pre-computed "loops_per_second" value.
17 */
18
Måns Rullgård44d06772015-11-06 12:44:01 +000019static __inline__ void __delay(unsigned long loops)
Wolfgang Denk6cb142f2006-03-12 02:12:27 +010020{
21 __asm__ __volatile__("1:\t%0 += -1;\n\t"
Aubrey.Li3f0606a2007-03-09 13:38:44 +080022 "cc = %0 == 0;\n\t"
23 "if ! cc jump 1b;\n":"=d"(loops)
24 :"0"(loops));
Wolfgang Denk6cb142f2006-03-12 02:12:27 +010025}
26
27/*
28 * Use only for very small delays ( < 1 msec). Should probably use a
29 * lookup table, really, as the multiplications take much too long with
30 * short delays. This is a "reasonable" implementation, though (and the
31 * first constant multiplications gets optimized away if the delay is
32 * a constant)
33 */
Måns Rullgård44d06772015-11-06 12:44:01 +000034static __inline__ void __udelay(unsigned long usecs)
Wolfgang Denk6cb142f2006-03-12 02:12:27 +010035{
36 __delay(usecs);
37}
38
39#endif