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2020-08-25Kernel: Switch singletons to use new Singleton classTom
MemoryManager cannot use the Singleton class because MemoryManager::initialize is called before the global constructors are run. That caused the Singleton to be re-initialized, causing it to create another MemoryManager instance. Fixes #3226
2020-08-22Revert "Kernel: Switch singletons to use new Singleton class"Andreas Kling
This reverts commit f48feae0b2a300992479abf0b2ded85e45ac6045.
2020-08-22Revert "Kernel: Move Singleton class to AK"Andreas Kling
This reverts commit f0906250a181c831508a45434b9f645ff98f33e4.
2020-08-22Revert "AK: Get rid of make_singleton function"Andreas Kling
This reverts commit 5a98e329d157a2db8379e0c97c6bdc1328027843.
2020-08-22AK: Get rid of make_singleton functionTom
Just default the InitFunction template argument.
2020-08-22Kernel: Move Singleton class to AKTom
2020-08-21Kernel: Switch singletons to use new Singleton classTom
Fixes #3226
2020-06-21Kernel: Use map_typed() in HPET code and add a register access helperAndreas Kling
2020-06-01HPET: Fix accessing HPET registersTom
This resolves a bochs panic during bootup: [Kernel]: HPET @ P0x07ff0fc0 00691951632p[HPET ] >>PANIC<< Unsupported HPET read at address 0x0000fed00100 These changes however don't fully resolve #2162
2020-05-16Kernel: Absorb LibBareMetal back into the kernelAndreas Kling
This was supposed to be the foundation for some kind of pre-kernel environment, but nobody is working on it right now, so let's move everything back into the kernel and remove all the confusion.
2020-05-16Kernel: Add TimeManagement::now_as_timeval()Andreas Kling
Hide the implementation of time-of-day computation in TimeManagement.
2020-05-16Kernel: Remove dubious use of "volatile" in HPET codeAndreas Kling
2020-05-08Kernel: Use NonnullRefPtrVector for HardwareTimer and HPETComparatorAndreas Kling
2020-04-18Kernel: Remove CommandLine::get() in favor of lookup()Andreas Kling
lookup() returns an Optional<String> which allows us to implement easy default values using lookup(key).value_or(default_value);
2020-04-16Kernel: Fix dumb logic typo in HardwareTimer::handle_irq()Andreas Kling
2020-04-16Kernel: Rename HardwareTimer::change_function() => set_callback()Andreas Kling
Also make it non-virtual since nothing needs to override it.
2020-04-16Kernel: Remove "stale callback" concept from time managementAndreas Kling
If a hardware timer doesn't have a callback registered, it's now simply represented by a null m_callback.
2020-04-16Kernel: Rename HardwareTimer::m_function_to_call => m_callbackAndreas Kling
2020-04-16Kernel: Remove an unnecessary indirection between timer and schedulerAndreas Kling
We don't need a wrapper Function object that just forwards the timer callback to the scheduler tick function. It already has the same signature, so we can just plug it in directly. :^) Same with the clock updating function.
2020-04-16Kernel: Simplify the way we pass HardwareTimers around a bitAndreas Kling
Instead of passing around indices into the m_hardware_timers vector, just pass around a HardwareTimer* instead.
2020-04-09Kernel: Simplify the Time management initializationLiav A
2020-04-09Kernel: Remove redundant "ACPI" from filenames in ACPI/Andreas Kling
2020-04-09Kernel: Remove "non-operational" ACPI parser stateAndreas Kling
If we don't support ACPI, just don't instantiate an ACPI parser. This is way less confusing than having a special parser class whose only purpose is to do nothing. We now search for the RSDP in ACPI::initialize() instead of letting the parser constructor do it. This allows us to defer the decision to create a parser until we're sure we can make a useful one.
2020-04-08Kernel: Rename KParams => Kernel::CommandLineAndreas Kling
Let's make this read more like English.
2020-04-01Kernel: Align read operation in HPET registers' blockLiav A
2020-03-23AK: Reduce header dependency graph of String.hAndreas Kling
String.h no longer pulls in StringView.h. We do this by moving a bunch of String functions out-of-line.
2020-03-19Kernel: Introduce the new Time management subsystemLiav A
This new subsystem includes better abstractions of how time will be handled in the OS. We take advantage of the existing RTC timer to aid in keeping time synchronized. This is standing in contrast to how we handled time-keeping in the kernel, where the PIT was responsible for that function in addition to update the scheduler about ticks. With that new advantage, we can easily change the ticking dynamically and still keep the time synchronized. In the process context, we no longer use a fixed declaration of TICKS_PER_SECOND, but we call the TimeManagement singleton class to provide us the right value. This allows us to use dynamic ticking in the future, a feature known as tickless kernel. The scheduler no longer does by himself the calculation of real time (Unix time), and just calls the TimeManagment singleton class to provide the value. Also, we can use 2 new boot arguments: - the "time" boot argument accpets either the value "modern", or "legacy". If "modern" is specified, the time management subsystem will try to setup HPET. Otherwise, for "legacy" value, the time subsystem will revert to use the PIT & RTC, leaving HPET disabled. If this boot argument is not specified, the default pattern is to try to setup HPET. - the "hpet" boot argumet accepts either the value "periodic" or "nonperiodic". If "periodic" is specified, the HPET will scan for periodic timers, and will assert if none are found. If only one is found, that timer will be assigned for the time-keeping task. If more than one is found, both time-keeping task & scheduler-ticking task will be assigned to periodic timers. If this boot argument is not specified, the default pattern is to try to scan for HPET periodic timers. This boot argument has no effect if HPET is disabled. In hardware context, PIT & RealTimeClock classes are merely inheriting from the HardwareTimer class, and they allow to use the old i8254 (PIT) and RTC devices, managing them via IO ports. By default, the RTC will be programmed to a frequency of 1024Hz. The PIT will be programmed to a frequency close to 1000Hz. About HPET, depending if we need to scan for periodic timers or not, we try to set a frequency close to 1000Hz for the time-keeping timer and scheduler-ticking timer. Also, if possible, we try to enable the Legacy replacement feature of the HPET. This feature if exists, instructs the chipset to disconnect both i8254 (PIT) and RTC. This behavior is observable on QEMU, and was verified against the source code: https://github.com/qemu/qemu/commit/ce967e2f33861b0e17753f97fa4527b5943c94b6 The HPETComparator class is inheriting from HardwareTimer class, and is responsible for an individual HPET comparator, which is essentially a timer. Therefore, it needs to call the singleton HPET class to perform HPET-related operations. The new abstraction of Hardware timers brings an opportunity of more new features in the foreseeable future. For example, we can change the callback function of each hardware timer, thus it makes it possible to swap missions between hardware timers, or to allow to use a hardware timer for other temporary missions (e.g. calibrating the LAPIC timer, measuring the CPU frequency, etc).