Split the ARM permission fields in the short descriptors into an access
flag and AP[2:1] as per the recommendation in the ARM ARM. This makes
the access flag available separately, which allows us to implement
EFI_MEMORY_RP memory analogous to how it will be implemented for
AArch64.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Large page support on 32-bit ARM is essentially a glorified contiguous
bit where 16 consecutive entries describing a contiguous range with the
same attributes are presented in a way that permits the TLB to cache its
translation with a single entry.
This was never wired up completely, and does not add a lot of value in
EFI, where the page granularity is 4k and we expect to be able to set RO
and XP permissions on individual pages.
Given that large page support complicates the handling of the XN bit at
the page level (which is in a different place depending on whether the
page is small or large), let's just rip it out.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3737
Apply uncrustify changes to .c/.h files in the ArmPkg package
Cc: Andrew Fish <afish@apple.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
Reviewed-by: Andrew Fish <afish@apple.com>
Unlike the AArch64 implementation of ArmMmuLib, which combines the
initial page table population code with the code that runs at later
stages to manage permission attributes in the page tables, ARM uses
two completely separate sets of routines for this.
Since ArmMmuLib is a static library, we can prevent duplication of
this code between different users, which usually only need one or
the other. (Note that LTO should also achieve the same.)
This also makes it easier to reason about modifying the cache
maintenance handling, and replace the set/way ops with by-VA
ops, since the code that performs the set/way ops only executes
when the MMU is still off.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif@nuviainc.com>
Ard Biesheuvel
Michael Kubacki
Ard Biesheuvel