audk/ArmPkg
Mark Rutland ee95f9e1fa ArmPkg/ArmLib: fix barriers in AArch64 ArmEnableMmu
The ARM architecture requires a DSB to complete TLB maintenance, with a
subsequent ISB being required to synchronize subsequent items in the
current instruction stream against the completed TLB maintenance.

The ArmEnableMmu function is currently missing the DSB, and hence the
TLB maintenance is not guaranteed to have completed at the point the MMU
is enabled. This may result in unpredictable behaviour.

The DSB subsequent to the write to SCTLR_EL1 is unnecessary; the ISB
alone is sufficient to complete all prior instructions and to
synchronise the new context with any subsequent instructions.

This patch adds missing DSBs to complete TLB maintenance, and removes
the unnecessary trailing DSB.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18749 6f19259b-4bc3-4df7-8a09-765794883524
2015-11-09 13:25:12 +00:00
..
Application/LinuxLoader ArmPkg/Application: Add new EFI application to boot Linux 2015-07-06 16:49:40 +00:00
Drivers ArmPkg: Purge unused/unneeded CPU-specific header files 2015-11-06 17:19:56 +00:00
Filesystem/SemihostFs ArmPkg/SemihostFs: Implement SetInfo() and handle seeking past the end of a file 2014-10-27 10:42:51 +00:00
Include ArmPkg: Purge unused/unneeded CPU-specific header files 2015-11-06 17:19:56 +00:00
Library ArmPkg/ArmLib: fix barriers in AArch64 ArmEnableMmu 2015-11-09 13:25:12 +00:00
ArmPkg.dec ArmPkg: split off ArmGicArchLib from ArmGicLib 2015-07-28 20:44:44 +00:00
ArmPkg.dsc ArmPkg: remove ARMv6 support code 2015-08-19 10:51:59 +00:00
Contributions.txt */Contributions.txt: Update example email address 2015-02-03 17:29:14 +00:00
License.txt EDK II Packages: Added License.txt files 2012-04-12 16:40:32 +00:00