Now the ACPI & PCI code is more safer, because we don't use raw pointers
or references to objects or data that are located in the physical
address space, so an accidental dereference cannot happen easily.
Instead, we use the PhysicalAddress class to represent those addresses.
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.
As suggested by Joshua, this commit adds the 2-clause BSD license as a
comment block to the top of every source file.
For the first pass, I've just added myself for simplicity. I encourage
everyone to add themselves as copyright holders of any file they've
added or modified in some significant way. If I've added myself in
error somewhere, feel free to replace it with the appropriate copyright
holder instead.
Going forward, all new source files should include a license header.
Also, PCI Initializer dismiss() now deletes the object correctly, and
the PCI initialization process no longer use the DMI decoder to
determine if PCI is supported.
grub configuration files include an entry to boot the OS without
ACPI support.
mmap() & mmap_region() methods are removed from ACPI & DMI components,
and we replace them with the new MM.allocate_kernel_region() helper.
Instead of doing a raw calculation for each VM address, from now on we
can use helper functions to do perform those calculations in a neat,
reusable and readable way.
During initialization of PCI MMIO access mechanism we ensure that we
have an allocation from the kernel virtual address space that cannot be
taken by other components in the OS.
Also, now we ensure that interrupts are disabled so mapping the region
doesn't fail.
In order to reduce overhead, map_device() will map the requested PCI
address only if it's not mapped already.
The run script has been changed so now we can boot a Q35 machine, that
supports PCI ECAM.
To ensure we will be able to load the machine, a PIIX3 IDE controller
was added to the Q35 machine configuration in the run script.
An AHCI controller was added to the i440fx machine configuration.
The new PCI subsystem is initialized during runtime.
PCI::Initializer is supposed to be called during early boot, to
perform a few tests, and initialize the proper configuration space
access mechanism. Kernel boot parameters can be specified by a user to
determine what tests will occur, to aid debugging on problematic
machines.
After that, PCI::Initializer should be dismissed.
PCI::IOAccess is a class that is derived from PCI::Access
class and implements PCI configuration space access mechanism via x86
IO ports.
PCI::MMIOAccess is a class that is derived from PCI::Access
and implements PCI configurtaion space access mechanism via memory
access.
The new PCI subsystem also supports determination of IO/MMIO space
needed by a device by checking a given BAR.
In addition, Every device or component that use the PCI subsystem has
changed to match the last changes.
