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Serenity Operating System
1/*
2 * Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
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 are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this
9 * list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#pragma once
28
29#include <AK/Function.h>
30#include <AK/RefCounted.h>
31#include <AK/String.h>
32#include <Kernel/Interrupts/IRQHandler.h>
33#include <Kernel/Time/TimeManagement.h>
34
35namespace Kernel {
36
37enum class HardwareTimerType {
38 i8253 = 0x1, /* PIT */
39 RTC = 0x2, /* Real Time Clock */
40 HighPrecisionEventTimer = 0x3 /* also known as IA-PC HPET */
41};
42
43class HardwareTimer : public RefCounted<HardwareTimer>
44 , public IRQHandler {
45public:
46 virtual HardwareTimerType timer_type() const = 0;
47 virtual const char* model() const = 0;
48 virtual const char* purpose() const override;
49
50 virtual void change_function(Function<void(const RegisterState&)>);
51 virtual size_t ticks_per_second() const = 0;
52
53 virtual bool is_periodic() const = 0;
54 virtual bool is_periodic_capable() const = 0;
55 virtual void set_periodic() = 0;
56 virtual void set_non_periodic() = 0;
57
58 virtual void reset_to_default_ticks_per_second() = 0;
59 virtual bool try_to_set_frequency(size_t frequency) = 0;
60 virtual bool is_capable_of_frequency(size_t frequency) const = 0;
61 virtual size_t calculate_nearest_possible_frequency(size_t frequency) const = 0;
62
63protected:
64 HardwareTimer(u8 irq_number, Function<void(const RegisterState&)>);
65 //^IRQHandler
66 virtual void handle_irq(const RegisterState&) override;
67 u64 m_frequency { OPTIMAL_TICKS_PER_SECOND_RATE };
68
69private:
70 Function<void(const RegisterState&)> m_function_to_call;
71};
72}