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Linux kernel mirror (for testing)
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1/* delay.c: Delay loops for sparc64
2 *
3 * Copyright (C) 2004 David S. Miller <davem@redhat.com>
4 *
5 * Based heavily upon x86 variant which is:
6 * Copyright (C) 1993 Linus Torvalds
7 * Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
8 */
9
10#include <linux/delay.h>
11
12void __delay(unsigned long loops)
13{
14 __asm__ __volatile__(
15" b,pt %%xcc, 1f\n"
16" cmp %0, 0\n"
17" .align 32\n"
18"1:\n"
19" bne,pt %%xcc, 1b\n"
20" subcc %0, 1, %0\n"
21 : "=&r" (loops)
22 : "0" (loops)
23 : "cc");
24}
25
26/* We used to multiply by HZ after shifting down by 32 bits
27 * but that runs into problems for higher values of HZ and
28 * slow cpus.
29 */
30void __const_udelay(unsigned long n)
31{
32 n *= 4;
33
34 n *= (cpu_data(raw_smp_processor_id()).udelay_val * (HZ/4));
35 n >>= 32;
36
37 __delay(n + 1);
38}
39
40void __udelay(unsigned long n)
41{
42 __const_udelay(n * 0x10c7UL);
43}
44
45
46void __ndelay(unsigned long n)
47{
48 __const_udelay(n * 0x5UL);
49}