This patch implements a simple, lightweight form of protection domains
using a pluggable framework. Currently, the following plugin is
available:
- Flat memory model with paging.
The overall goal of a protection domain implementation within this
framework is to define a set of resources that should be accessible to
each protection domain and to prevent that protection domain from
accessing other resources. The details of each implementation of
protection domains may differ substantially, but they should all be
guided by the principle of least privilege. However, that idealized
principle is balanced against the practical objectives of limiting the
number of relatively time-consuming context switches and minimizing
changes to existing code.
For additional information, please refer to cpu/x86/mm/README.md.
This patch also causes the C compiler to be used as the default linker
and assembler.
This patch adds support for PCI BAR1 and also changes
the pci_init(), instead of having one function for each `bar`
we now set the `bar` to pci_config_addr_t parameter before calling
the pci_init() function..
This patch adds the 'meta' field to the generic driver structure to
point to optional driver-defined metadata. It also modifies the
associated initialization routine to populate it and updates the 16X50
UART driver to use the new initialization routine signature. This
patch also adds a function to perform PCI configuration register
writes, definitions for the PCI Command configuration register address
and some of the bits in that register, and a function to set
additional bits in that register. Finally, it adds macros to help
with performing MMIO to and from PCI devices.
This patch adds a driver for an MMIO-accessible 16X50 UART. It
assumes that the boot firmware assigned an MMIO range to the UART. It
operates in polled mode with FIFOs enabled.
