commit 928747fc1dd3fd01f97047ca8f330758ff588dda
author Daniel Boulby <daniel.boulby@arm.com> Tue May 25 18:09:34 2021 +0100
committer Daniel Boulby <daniel.boulby@arm.com> Thu Feb 03 11:33:49 2022 +0000
tree 00470874a8f45516837e852d67663bfa368913e7
parent 95fb1aa7b5f54ae33a8e159e6147cfdcbfc43d1c

fix(el3-runtime): set unset pstate bits to default

During a transition to a higher EL some of the PSTATE bits are not set
by hardware, this means that their state may be leaked from lower ELs.
This patch sets those bits to a default value upon entry to EL3.

This patch was tested using a debugger to check the PSTATE values
are correctly set. As well as adding a test in the next patch to
ensure the PSTATE in lower ELs is still maintained after this change.

Change-Id: Ie546acbca7b9aa3c86bd68185edded91b2a64ae5
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>

Makefile

diff --git a/Makefile b/Makefile
index a238ee4..1baacf0 100644
--- a/Makefile
+++ b/Makefile
@@ -277,6 +277,10 @@
 ENABLE_FEAT_ECV		=	1
 endif
 
+ifeq "8.4" "$(word 1, $(sort 8.4 $(ARM_ARCH_MAJOR).$(ARM_ARCH_MINOR)))"
+ENABLE_FEAT_DIT		= 	1
+endif
+
 ifneq ($(findstring armclang,$(notdir $(CC))),)
 TF_CFLAGS_aarch32	=	-target arm-arm-none-eabi $(march32-directive)
 TF_CFLAGS_aarch64	=	-target aarch64-arm-none-eabi $(march64-directive)
@@ -1040,6 +1044,7 @@
         USE_SP804_TIMER \
         ENABLE_FEAT_RNG \
         ENABLE_FEAT_SB \
+        ENABLE_FEAT_DIT \
         PSA_FWU_SUPPORT \
         ENABLE_TRBE_FOR_NS \
         ENABLE_SYS_REG_TRACE_FOR_NS \
@@ -1154,6 +1159,7 @@
         USE_SP804_TIMER \
         ENABLE_FEAT_RNG \
         ENABLE_FEAT_SB \
+        ENABLE_FEAT_DIT \
         NR_OF_FW_BANKS \
         NR_OF_IMAGES_IN_FW_BANK \
         PSA_FWU_SUPPORT \