We should aim to reliably determine if PCI hardware exists or not, and
we should consider the ACPI MCFG table in that test. Although it is
unusual to see an hardware setup where the PCI host bridge does not
respond to x86 IO instructions, it is expected to happen at least on the
QEMU microvm machine type as the host bridge only responds to memory
mapped IO requests. Therefore, we first test if ACPI is enabled, and we
try to use it to fetch the MCFG table. Later on we could also add FDT
parsing as part of the PCI IO test which would be useful for the QEMU
microvm machine type.
It seems more correct to let each platform to define its own sequence of
initialization of the PCI bus, so let's remove the #if flags and just
put the entire Initializer.cpp file in the appropriate code directory.
2022-09-20 18:43:05 +01:00
Renamed from Kernel/Bus/PCI/Initializer.cpp (Browse further)