Add documentation for CTX_INCLUDE_MTE_REGS

A new build flag, CTX_INCLUDE_MTE_REGS, has been added; this patch adds
documentation for it in the User Guide along with instructions of what
different values mean.

Change-Id: I430a9c6ced06b1b6be317edbeff4f5530e30f63a
Signed-off-by: Justin Chadwell <justin.chadwell@arm.com>
This commit is contained in:
Justin Chadwell 2019-07-18 16:16:32 +01:00
parent 9dd94382bd
commit 88d493fb1b
2 changed files with 18 additions and 1 deletions

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@ -2581,7 +2581,16 @@ Armv8.5-A
~~~~~~~~~
- Branch Target Identification feature is selected by ``BRANCH_PROTECTION``
option set to 1. This option defaults to 0 and this is an experimental feature.
option set to 1. This option defaults to 0 and this is an experimental
feature.
- Memory Tagging Extension feature is unconditionally enabled for both worlds
(at EL0 and S-EL0) if it is only supported at EL0. If instead it is
implemented at all ELs, it is unconditionally enabled for only the normal
world. To enable it for the secure world as well, the build option
``CTX_INCLUDE_MTE_REGS`` is required. If the hardware does not implement
MTE support at all, it is always disabled, no matter what build options
are used.
Armv7-A
~~~~~~~

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@ -383,6 +383,13 @@ Common build options
registers to be included when saving and restoring the CPU context. Default
is 0.
- ``CTX_INCLUDE_MTE_REGS``: Enables register saving/reloading support for
ARMv8.5 Memory Tagging Extension. A value of 0 will disable
saving/reloading and restrict the use of MTE to the normal world if the
CPU has support, while a value of 1 enables the saving/reloading, allowing
the use of MTE in both the secure and non-secure worlds. Default is 0
(disabled) and this feature is experimental.
- ``CTX_INCLUDE_PAUTH_REGS``: Boolean option that, when set to 1, enables
Pointer Authentication for Secure world. This will cause the ARMv8.3-PAuth
registers to be included when saving and restoring the CPU context as
@ -798,6 +805,7 @@ Common build options
cluster platforms). If this option is enabled, then warm boot path
enables D-caches immediately after enabling MMU. This option defaults to 0.
Arm development platform specific build options
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^