1/*
2 * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
3 * All rights reserved.
4 *
5 * This software was developed by the University of Cambridge Computer
6 * Laboratory as part of the CTSRD Project, with support from the UK Higher
7 * Education Innovation Fund (HEIF).
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are
11 * met: redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer;
13 * redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution;
16 * neither the name of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#ifndef __KERN_FREEBSD_EVENTS_HH__
34#define __KERN_FREEBSD_EVENTS_HH__
35
36#include "kern/system_events.hh"
37
38namespace FreeBSD {
39
40/** A class to skip udelay() and related calls in the kernel.
41 * This class has two additional parameters that take the argument to udelay and
42 * manipulated it to come up with ns and eventually ticks to quiesce for.
43 * See descriptions of argDivToNs and argMultToNs below.
44 */
45class UDelayEvent : public SkipFuncEvent
46{
47  private:
48    /** value to divide arg by to create ns. This is present beacues the linux
49     * kernel code sometime precomputes the first multiply that is done in
50     * udelay() if the parameter is a constant. We need to undo it so here is
51     * how. */
52    uint64_t argDivToNs;
53
54    /** value to multiple arg by to create ns. Nominally, this is 1000 to
55     * convert us to ns, but since linux can do some preprocessing of constant
56     * values something else might be required. */
57    uint64_t argMultToNs;
58
59  public:
60    UDelayEvent(PCEventQueue *q, const std::string &desc, Addr addr,
61            uint64_t mult, uint64_t div)
62        : SkipFuncEvent(q, desc, addr), argDivToNs(div), argMultToNs(mult) {}
63    virtual void process(ThreadContext *xc);
64};
65
66}
67
68#endif
69