nb/intel/common/fixed_bars.h: Add new read/write accessors

The {MCH,DMI,EP}BAR macros can be used for both reading and writing.
While this can sometimes be useful, compile-time overflow checking is
limited. Moreover, and-masks need to be bit-wise negated, which is easy
to forget and may result in spurious overflow warnings, and silencing
them with a cast also suppresses true integer overflow issues.

To address these limitations and for consistency with the existing MMIO
API (arch/mmio.h and device/mmio.h), these macros will be replaced with
prefixed wrappers around MMIO API functions. However, existing platform
code needs to be refactored, and the risk of introducing regressions is
substantial. To minimize the risk of breakage, the bulk of the platform
code changes will be verified using reproducible builds.

This patch introduces the new accessors, to be put to use in follow-ups.
These accessors are implemented as macros so that subsequent commits can
be verified using reproducible builds. They will be replaced with actual
functions after refactoring all platforms.

Change-Id: I85376a9e2f6cd042b41036f90de7f9edc7ad4508
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51864
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions