1 | /* $Id: bs3-cmn-PitIrqHandler.c 82968 2020-02-04 10:35:17Z vboxsync $ */
|
---|
2 | /** @file
|
---|
3 | * BS3Kit - The PIT IRQ Handler and associated data.
|
---|
4 | */
|
---|
5 |
|
---|
6 | /*
|
---|
7 | * Copyright (C) 2007-2020 Oracle Corporation
|
---|
8 | *
|
---|
9 | * This file is part of VirtualBox Open Source Edition (OSE), as
|
---|
10 | * available from http://www.virtualbox.org. This file is free software;
|
---|
11 | * you can redistribute it and/or modify it under the terms of the GNU
|
---|
12 | * General Public License (GPL) as published by the Free Software
|
---|
13 | * Foundation, in version 2 as it comes in the "COPYING" file of the
|
---|
14 | * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
|
---|
15 | * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
|
---|
16 | *
|
---|
17 | * The contents of this file may alternatively be used under the terms
|
---|
18 | * of the Common Development and Distribution License Version 1.0
|
---|
19 | * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
|
---|
20 | * VirtualBox OSE distribution, in which case the provisions of the
|
---|
21 | * CDDL are applicable instead of those of the GPL.
|
---|
22 | *
|
---|
23 | * You may elect to license modified versions of this file under the
|
---|
24 | * terms and conditions of either the GPL or the CDDL or both.
|
---|
25 | */
|
---|
26 |
|
---|
27 |
|
---|
28 | /*********************************************************************************************************************************
|
---|
29 | * Header Files *
|
---|
30 | *********************************************************************************************************************************/
|
---|
31 | #include "bs3kit-template-header.h"
|
---|
32 | #include <iprt/asm-amd64-x86.h>
|
---|
33 |
|
---|
34 |
|
---|
35 | /*********************************************************************************************************************************
|
---|
36 | * Global Variables *
|
---|
37 | *********************************************************************************************************************************/
|
---|
38 | #if ARCH_BITS == 16
|
---|
39 | /** Nano seconds (approx) since last the PIT timer was started. */
|
---|
40 | uint64_t volatile g_cBs3PitNs = 0;
|
---|
41 | /** Milliseconds seconds (very approx) since last the PIT timer was started. */
|
---|
42 | uint64_t volatile g_cBs3PitMs = 0;
|
---|
43 | /** Number of ticks since last the PIT timer was started. */
|
---|
44 | uint32_t volatile g_cBs3PitTicks = 0;
|
---|
45 | /** The current interval in nanon seconds. */
|
---|
46 | uint32_t g_cBs3PitIntervalNs = 0;
|
---|
47 | /** The current interval in milliseconds (approximately).
|
---|
48 | * This is 0 if not yet started (used for checking the state internally). */
|
---|
49 | uint16_t volatile g_cBs3PitIntervalMs = 0;
|
---|
50 | /** The current PIT frequency (approximately). 0 if not yet started. */
|
---|
51 | uint16_t g_cBs3PitIntervalHz = 0;
|
---|
52 | #endif
|
---|
53 |
|
---|
54 |
|
---|
55 | BS3_DECL_NEAR_CALLBACK(void) BS3_CMN_NM(bs3PitIrqHandler)(PBS3TRAPFRAME pTrapFrame)
|
---|
56 | {
|
---|
57 | uint16_t cMsIntercal = g_cBs3PitIntervalMs;
|
---|
58 | if (cMsIntercal)
|
---|
59 | {
|
---|
60 | g_cBs3PitMs += cMsIntercal;
|
---|
61 | g_cBs3PitNs += g_cBs3PitIntervalNs;
|
---|
62 | g_cBs3PitTicks++;
|
---|
63 | }
|
---|
64 | NOREF(pTrapFrame);
|
---|
65 | ASMOutU8(0x20, 0x20); /** @todo function! */
|
---|
66 | }
|
---|
67 |
|
---|