[Buildroot] [PATCH 1/6] boot/arm-trusted-firmware: support 32bit Arm targets

[Thomas Petazzoni <thomas.petazzoni@bootlin.com>]

Hello,

On Wed,  6 Mar 2019 11:11:35 +0100
Etienne Carriere <etienne.carriere@linaro.org> wrote:

> This change allows one to build the TF-A (Trusted Firmware A) for
> 32bit Armv7 and Armv8 platforms which arm-trusted-firmware supports
> since release v1.5.
> 
> BR2_aarch64 is changed to BR2_ARM_CPU_ARMV8A as the later complemented
> by BR2_ARM_CPU_ARMV7A better represents to architectures that can
> support Arm Trusted Firmware A.
> 
> When BR2_arm is enabled, TF-A is built in Aarch32 mode.
> Selection between Armv8-A (default) and Armv7-A (ARM_ARCH_MAJOR=7) is
> expected from BR2_TARGET_ARM_TRUSTED_FIRMWARE_ADDITIONAL_VARIABLES.

It seems a bit annoying to require passing ARM_ARCH_MAJOR=7 in those
additional variable. Why don't we do it automatically in
arm-trusted-firmware.mk. We have all the knowledge required, no?

> +ifeq ($(BR2_arm),y)
> +ARM_TRUSTED_FIRMWARE_MAKE_OPTS += ARCH=aarch32

Can we do:

ifeq ($(BR2_arm),y)
ARM_TRUSTED_FIRMWARE_MAKE_OPTS += ARCH=aarch32 ARM_ARCH_MAJOR=7
else
ARM_TRUSTED_FIRMWARE_MAKE_OPTS += ARCH=aarch64 ARM_ARCH_MAJOR=8
endif

for example ?

Thomas
-- 
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com