source: mainline/kernel/arch/ia64/src/drivers/it.c@ 11675207

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 11675207 was 11675207, checked in by jermar <jermar@…>, 17 years ago

Move everything to kernel/.

  • Property mode set to 100644
File size: 2.5 KB
Line 
1/*
2 * Copyright (C) 2005 Jakub Jermar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 /** @addtogroup ia64
30 * @{
31 */
32/** @file
33 */
34
35/** Interval Timer driver. */
36
37#include <arch/drivers/it.h>
38#include <arch/ski/ski.h>
39#include <arch/interrupt.h>
40#include <arch/register.h>
41#include <arch/asm.h>
42#include <arch/barrier.h>
43#include <time/clock.h>
44#include <arch.h>
45
46
47#define IT_SERVICE_CLOCKS 64
48
49/** Initialize Interval Timer. */
50void it_init(void)
51{
52 cr_itv_t itv;
53
54 /* initialize Interval Timer external interrupt vector */
55 itv.value = itv_read();
56 itv.vector = INTERRUPT_TIMER;
57 itv.m = 0;
58 itv_write(itv.value);
59
60 /* set Interval Timer Counter to zero */
61 itc_write(0);
62
63 /* generate first Interval Timer interrupt in IT_DELTA ticks */
64 itm_write(IT_DELTA);
65
66 /* propagate changes */
67 srlz_d();
68}
69
70
71/** Process Interval Timer interrupt. */
72void it_interrupt(void)
73{
74 int64_t c;
75 int64_t m;
76
77 eoi_write(EOI);
78
79 m=itm_read();
80
81 while(1)
82 {
83
84 c=itc_read();
85 c+=IT_SERVICE_CLOCKS;
86
87 m+=IT_DELTA;
88 if(m-c<0)
89 {
90 CPU->missed_clock_ticks++;
91 }
92 else break;
93 }
94
95 itm_write(m);
96 srlz_d(); /* propagate changes */
97
98
99
100 clock();
101 poll_keyboard();
102}
103
104 /** @}
105 */
106
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