toolchain/toolchain-external/toolchain-external-arm-arm: add dependency on NEON

While testing Buildroot on a Cortex-A5 that doesn't provide NEON, we
found out that a system generated with the ARM toolchain from Arm
didn't boot. It turns out that this ARM toolchain is built with:

  --with-arch=armv7-a --with-fpu=neon --with-float=hard --with-mode=thumb

So, it uses NEON as its FPU, which means it can only work on CPU cores
that have NEON support. This commit adds the appropriate dependency to
the toolchain-external-arm-arm package, and adjusts the Config.in help
text accordingly.

While at it, it also drops the part of the Config.in help text that
says the code is tuned for Cortex-A9, as it is not the case: it was
the case for the Linaro toolchain (built with --with-tune=cortex-a9),
but not for the ARM toolchain, for which no specific --with-tune is
passed.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Romain Naour <romain.naour@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

diff --git a/toolchain/toolchain-external/toolchain-external-arm-arm/Config.in b/toolchain/toolchain-external/toolchain-external-arm-arm/Config.in
index 4748ab53ae252f19a78e8c3847973267d88be42e..29509635a3ecf11cd9ea95eb27c304d1900e089f 100644 (file)
--- a/toolchain/toolchain-external/toolchain-external-arm-arm/Config.in
+++ b/toolchain/toolchain-external/toolchain-external-arm-arm/Config.in
@@ -1,12 +1,13 @@
-comment "Arm toolchains available for Cortex-A + EABIhf"
+comment "Arm toolchains available for Cortex-A with NEON + EABIhf"
        depends on BR2_arm
-       depends on !BR2_ARM_CPU_ARMV7A || !BR2_ARM_EABIHF
+       depends on !BR2_ARM_CPU_ARMV7A || !BR2_ARM_EABIHF || !BR2_ARM_CPU_HAS_NEON
        depends on !BR2_STATIC_LIBS
 
 config BR2_TOOLCHAIN_EXTERNAL_ARM_ARM
        bool "Arm ARM 2019.12"
        depends on BR2_arm
        depends on BR2_ARM_CPU_ARMV7A || BR2_ARM_CPU_ARMV8A
+       depends on BR2_ARM_CPU_HAS_NEON
        depends on BR2_HOSTARCH = "x86_64"
        depends on BR2_ARM_EABIHF
        depends on !BR2_STATIC_LIBS
@@ -20,10 +21,10 @@ config BR2_TOOLCHAIN_EXTERNAL_ARM_ARM
        select BR2_TOOLCHAIN_HAS_OPENMP
        help
          Arm toolchain for the ARM architecture. It uses GCC 9.2.1,
-         GDB 8.3.0, glibc 2.30, Binutils 2.33.1. It generates code that
-         runs on all Cortex-A profile devices, but tuned for the
-         Cortex-A9. The code generated uses the hard floating point
-         calling convention, and uses the VFPv3-D16 FPU instructions.
+         GDB 8.3.0, glibc 2.30, Binutils 2.33.1. It generates code
+         that runs on all Cortex-A profile devices. The code
+         generated uses the hard floating point calling convention,
+         and uses the NEON FPU instructions.
 
          This is the same toolchain that was previously distributed by
          Linaro.