path: root/docs/firmware-design.rst
diff options
authorAlexei Fedorov <Alexei.Fedorov@arm.com>2019-03-11 16:51:47 +0000
committerAlexei Fedorov <Alexei.Fedorov@arm.com>2019-03-12 17:04:50 +0000
commitfa6f774b285dc9ee4d312a955195a079fc4d2bb7 (patch)
tree82b0e2c24ec28f0242dabbff02cf283704e56c4c /docs/firmware-design.rst
parentc48d02bade88b07fa7f43aa44e5217f68e5d047f (diff)
Allow setting compiler's target architecture
Change-Id: I56ea088f415bdb9077c385bd3450ff4b2cfa2eac Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
Diffstat (limited to 'docs/firmware-design.rst')
1 files changed, 5 insertions, 1 deletions
diff --git a/docs/firmware-design.rst b/docs/firmware-design.rst
index 9e206dc0f3..52520ea12d 100644
--- a/docs/firmware-design.rst
+++ b/docs/firmware-design.rst
@@ -2521,7 +2521,7 @@ section lists the usage of Architecture Extensions, and build flags
controlling them.
In general, and unless individually mentioned, the build options
-``ARM_ARCH_MAJOR`` and ``ARM_ARCH_MINOR`` selects the Architecture Extension to
+``ARM_ARCH_MAJOR`` and ``ARM_ARCH_MINOR`` select the Architecture Extension to
target when building TF-A. Subsequent Arm Architecture Extensions are backward
compatible with previous versions.
@@ -2570,6 +2570,10 @@ Armv8.3-A
``CTX_INCLUDE_PAUTH_REGS`` to 1. This enables pointer authentication in BL1,
BL2, BL31, and the TSP if it is used.
+ If ``ARM_ARCH_MAJOR == 8`` and ``ARM_ARCH_MINOR >= 3`` the code footprint of
+ enabling PAuth is lower because the compiler will use the optimized
+ PAuth instructions rather than the backwards-compatible ones.