Allow setting compiler's target architecture
Change-Id: I56ea088f415bdb9077c385bd3450ff4b2cfa2eac
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
diff --git a/Makefile b/Makefile
index 6386bef..5621c53 100644
--- a/Makefile
+++ b/Makefile
@@ -147,26 +147,34 @@
# Will set march32-directive from platform configuration
else
target32-directive = -target armv8a-none-eabi
+
+# Set the compiler's target architecture profile based on ARM_ARCH_MINOR option
+ifeq (${ARM_ARCH_MINOR},0)
march32-directive = -march=armv8-a
+march64-directive = -march=armv8-a
+else
+march32-directive = -march=armv8.${ARM_ARCH_MINOR}-a
+march64-directive = -march=armv8.${ARM_ARCH_MINOR}-a
+endif
endif
ifneq ($(findstring armclang,$(notdir $(CC))),)
TF_CFLAGS_aarch32 = -target arm-arm-none-eabi $(march32-directive)
-TF_CFLAGS_aarch64 = -target aarch64-arm-none-eabi -march=armv8-a
+TF_CFLAGS_aarch64 = -target aarch64-arm-none-eabi $(march64-directive)
LD = $(LINKER)
AS = $(CC) -c -x assembler-with-cpp $(TF_CFLAGS_$(ARCH))
CPP = $(CC) -E $(TF_CFLAGS_$(ARCH))
PP = $(CC) -E $(TF_CFLAGS_$(ARCH))
else ifneq ($(findstring clang,$(notdir $(CC))),)
TF_CFLAGS_aarch32 = $(target32-directive) $(march32-directive)
-TF_CFLAGS_aarch64 = -target aarch64-elf
+TF_CFLAGS_aarch64 = -target aarch64-elf $(march64-directive)
LD = $(LINKER)
AS = $(CC) -c -x assembler-with-cpp $(TF_CFLAGS_$(ARCH))
CPP = $(CC) -E
PP = $(CC) -E
else
TF_CFLAGS_aarch32 = $(march32-directive)
-TF_CFLAGS_aarch64 = -march=armv8-a
+TF_CFLAGS_aarch64 = $(march64-directive)
LD = $(LINKER)
endif
@@ -182,15 +190,7 @@
TF_CFLAGS_aarch64 += -mgeneral-regs-only -mstrict-align
ASFLAGS_aarch32 = $(march32-directive)
-ASFLAGS_aarch64 = -march=armv8-a
-
-# Set the compiler to ARMv8.3 mode so that it uses all the ARMv8.3-PAuth
-# instructions. Keeping it in 8.0 would make the compiler emit
-# backwards-compatible hint instructions, which needs more space.
-ifeq (${ENABLE_PAUTH},1)
-TF_CFLAGS_aarch64 += -march=armv8.3-a
-ASFLAGS_aarch64 += -march=armv8.3-a
-endif
+ASFLAGS_aarch64 = $(march64-directive)
WARNING1 := -Wextra
WARNING1 += -Wunused -Wno-unused-parameter
diff --git a/docs/firmware-design.rst b/docs/firmware-design.rst
index 9e206dc..52520ea 100644
--- a/docs/firmware-design.rst
+++ b/docs/firmware-design.rst
@@ -2521,7 +2521,7 @@
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 @@
``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.
+
Armv7-A
~~~~~~~