ladybird/Kernel/InterruptHandler.cpp
Liav A 1ee37245cd Kernel: Introduce IRQ sharing support
The support is very basic - Each component that needs to handle IRQs
inherits from InterruptHandler class. When the InterruptHandler
constructor is called it registers itself in a SharedInterruptHandler.
When an IRQ is fired, the SharedInterruptHandler is invoked, then it
iterates through a list of the registered InterruptHandlers.

Also, InterruptEnabler class was created to provide a way to enable IRQ
handling temporarily, similar to InterruptDisabler (in CPU.h, which does
the opposite).

In addition to that a PCI::Device class has been added, that inherits
from InterruptHandler.
2020-01-22 12:22:09 +01:00

75 lines
2.5 KiB
C++

/*
* Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <Kernel/InterruptHandler.h>
#include <Kernel/SharedInterruptHandler.h>
InterruptHandler::InterruptHandler(u8 irq)
: m_irq_number(irq)
{
SharedInterruptHandler::from(m_irq_number).register_handler(*this);
disable_interrupts();
}
InterruptHandler::~InterruptHandler()
{
disable_interrupts();
SharedInterruptHandler::from(m_irq_number).unregister_handler(*this);
}
void InterruptHandler::enable_interrupts()
{
m_enabled = true;
}
void InterruptHandler::change_irq_number(u8 irq_number)
{
bool was_enabled = m_enabled;
disable_interrupts();
SharedInterruptHandler::from(m_irq_number).unregister_handler(*this);
m_irq_number = irq_number;
SharedInterruptHandler::from(m_irq_number).register_handler(*this);
if (was_enabled)
enable_interrupts();
}
void InterruptHandler::disable_interrupts()
{
m_enabled = false;
}
InterruptHandler::Enabler::Enabler(InterruptHandler& handler)
: m_handler(handler)
, m_was_enabled(m_handler.is_enabled())
{
m_handler.enable_interrupts();
}
InterruptHandler::Enabler::~Enabler()
{
if (!m_was_enabled)
m_handler.disable_interrupts();
}