1#ifndef _ASM_IA64_DELAY_H
2#define _ASM_IA64_DELAY_H
3
4/*
5 * Delay routines using a pre-computed "cycles/usec" value.
6 *
7 * Copyright (C) 1998, 1999 Hewlett-Packard Co
8 * Copyright (C) 1998, 1999 David Mosberger-Tang <davidm@hpl.hp.com>
9 * Copyright (C) 1999 VA Linux Systems
10 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
11 * Copyright (C) 1999 Asit Mallick <asit.k.mallick@intel.com>
12 * Copyright (C) 1999 Don Dugger <don.dugger@intel.com>
13 */
14
15#include <linux/config.h>
16#include <linux/kernel.h>
17#include <linux/sched.h>
18
19#include <asm/processor.h>
20
21static __inline__ void
22ia64_set_itm (unsigned long val)
23{
24	__asm__ __volatile__("mov cr.itm=%0;; srlz.d;;" :: "r"(val) : "memory");
25}
26
27static __inline__ unsigned long
28ia64_get_itm (void)
29{
30	unsigned long result;
31
32	__asm__ __volatile__("mov %0=cr.itm;; srlz.d;;" : "=r"(result) :: "memory");
33	return result;
34}
35
36static __inline__ void
37ia64_set_itv (unsigned long val)
38{
39	__asm__ __volatile__("mov cr.itv=%0;; srlz.d;;" :: "r"(val) : "memory");
40}
41
42static __inline__ void
43ia64_set_itc (unsigned long val)
44{
45	__asm__ __volatile__("mov ar.itc=%0;; srlz.d;;" :: "r"(val) : "memory");
46}
47
48static __inline__ unsigned long
49ia64_get_itc (void)
50{
51	unsigned long result;
52
53	__asm__ __volatile__("mov %0=ar.itc" : "=r"(result) :: "memory");
54#ifdef CONFIG_ITANIUM
55	while (__builtin_expect ((__s32) result == -1, 0))
56		__asm__ __volatile__("mov %0=ar.itc" : "=r"(result) :: "memory");
57#endif
58	return result;
59}
60
61static __inline__ void
62__delay (unsigned long loops)
63{
64        unsigned long saved_ar_lc;
65
66	if (loops < 1)
67		return;
68
69	__asm__ __volatile__("mov %0=ar.lc;;" : "=r"(saved_ar_lc));
70	__asm__ __volatile__("mov ar.lc=%0;;" :: "r"(loops - 1));
71        __asm__ __volatile__("1:\tbr.cloop.sptk.few 1b;;");
72	__asm__ __volatile__("mov ar.lc=%0" :: "r"(saved_ar_lc));
73}
74
75static __inline__ void
76udelay (unsigned long usecs)
77{
78	unsigned long start = ia64_get_itc();
79	unsigned long cycles = usecs*local_cpu_data->cyc_per_usec;
80
81	while (ia64_get_itc() - start < cycles)
82		/* skip */;
83}
84
85#endif /* _ASM_IA64_DELAY_H */
86