ARMv7 target is driven by ARM_ARCH_MAJOR==7
External build environment shall sets directive ARM_ARCH_MAJOR to 7
to specify a target ARMv7-A core.
As ARM-TF expects AARCH to be set, ARM_ARCH_MAJOR==7 mandates
AARCH=aarch32.
The toolchain target architecture/cpu is delegated after the platform
configuration is parsed. Platform shall define target core through
ARM_CORTEX_A<x>=yes, <x> being 5, 7, 9, 12, 15 and/or 17.
Platform can bypass ARM_CORTEX_A<x>=yes directive and provide straight
the toolchain target directive through MARCH32_DIRECTIVE.
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
diff --git a/make_helpers/armv7-a-cpus.mk b/make_helpers/armv7-a-cpus.mk
new file mode 100644
index 0000000..5a1c75c
--- /dev/null
+++ b/make_helpers/armv7-a-cpus.mk
@@ -0,0 +1,33 @@
+#
+# Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+ifneq (${ARCH},aarch32)
+$(error ARM_ARCH_MAJOR=7 mandates ARCH=aarch32)
+endif
+
+# For ARMv7, set march32 from platform directive ARMV7_CORTEX_Ax=yes
+# and ARM_WITH_NEON=yes/no.
+#
+# GCC and Clang require -march=armv7-a for C-A9 and -march=armv7ve for C-A15.
+# armClang requires -march=armv7-a for all ARMv7 Cortex-A. To comply with
+# all, just drop -march and supply only -mcpu.
+
+# Platform can override march32-directive through MARCH32_DIRECTIVE
+ifdef MARCH32_DIRECTIVE
+march32-directive := $(MARCH32_DIRECTIVE)
+else
+march32-set-${ARM_CORTEX_A5} := -mcpu=cortex-a5
+march32-set-${ARM_CORTEX_A7} := -mcpu=cortex-a7
+march32-set-${ARM_CORTEX_A9} := -mcpu=cortex-a9
+march32-set-${ARM_CORTEX_A12} := -mcpu=cortex-a12
+march32-set-${ARM_CORTEX_A15} := -mcpu=cortex-a15
+march32-set-${ARM_CORTEX_A17} := -mcpu=cortex-a17
+march32-neon-$(ARM_WITH_NEON) := -mfpu=neon
+
+# default to -march=armv7-a as target directive
+march32-set-yes ?= -march=armv7-a
+march32-directive := ${march32-set-yes} ${march32-neon-yes}
+endif