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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Paul Mundta23ba432007-11-28 20:19:38 +09002 * arch/sh/lib64/udelay.c
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * Delay routines, using a pre-computed "loops_per_jiffy" value.
5 *
6 * Copyright (C) 2000, 2001 Paolo Alberelli
7 * Copyright (C) 2003, 2004 Paul Mundt
8 *
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License. See the file "COPYING" in the main directory of this archive
11 * for more details.
12 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070013#include <linux/sched.h>
14#include <asm/param.h>
15
Linus Torvalds1da177e2005-04-16 15:20:36 -070016/*
17 * Use only for very small delays (< 1 msec).
18 *
19 * The active part of our cycle counter is only 32-bits wide, and
20 * we're treating the difference between two marks as signed. On
21 * a 1GHz box, that's about 2 seconds.
22 */
23
Paul Mundt7b9726a2008-03-06 17:23:15 +090024void __delay(unsigned long loops)
Linus Torvalds1da177e2005-04-16 15:20:36 -070025{
26 long long dummy;
27 __asm__ __volatile__("gettr tr0, %1\n\t"
28 "pta $+4, tr0\n\t"
29 "addi %0, -1, %0\n\t"
30 "bne %0, r63, tr0\n\t"
31 "ptabs %1, tr0\n\t":"=r"(loops),
32 "=r"(dummy)
33 :"0"(loops));
34}
35
Paul Mundt7b9726a2008-03-06 17:23:15 +090036inline void __const_udelay(unsigned long xloops)
Linus Torvalds1da177e2005-04-16 15:20:36 -070037{
Paul Mundt7b9726a2008-03-06 17:23:15 +090038 __delay(xloops * (HZ * cpu_data[raw_smp_processor_id()].loops_per_jiffy));
Linus Torvalds1da177e2005-04-16 15:20:36 -070039}
40
Paul Mundt7b9726a2008-03-06 17:23:15 +090041void __udelay(unsigned long usecs)
Linus Torvalds1da177e2005-04-16 15:20:36 -070042{
Paul Mundt7b9726a2008-03-06 17:23:15 +090043 __const_udelay(usecs * 0x000010c6); /* 2**32 / 1000000 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070044}
45
Paul Mundt7b9726a2008-03-06 17:23:15 +090046void __ndelay(unsigned long nsecs)
Linus Torvalds1da177e2005-04-16 15:20:36 -070047{
Paul Mundt7b9726a2008-03-06 17:23:15 +090048 __const_udelay(nsecs * 0x00000005);
Linus Torvalds1da177e2005-04-16 15:20:36 -070049}