Re: [dpdk-dev] [PATCH v8 5/5] doc: add aarch32 build guidance

[Aaron Conole <aconole@redhat.com>]

Juraj Linkeš <juraj.linkes@pantheon.tech> writes:

> From: Phil Yang <phil.yang@arm.com>
>
> Add cross-compiling guidance for 32-bit aarch32 DPDK on aarch64 host.
>
> Signed-off-by: Phil Yang <phil.yang@arm.com>
> ---
>  .../linux_gsg/cross_build_dpdk_for_arm64.rst  | 30 ++++++++++++++-----
>  1 file changed, 23 insertions(+), 7 deletions(-)
>
> diff --git a/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst b/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst
> index c5875a6d5..07085e3ea 100644
> --- a/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst
> +++ b/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst
> @@ -1,15 +1,16 @@
>  ..  SPDX-License-Identifier: BSD-3-Clause
>      Copyright(c) 2018 ARM Corporation.
>  
> -Cross compile DPDK for ARM64
> -============================
> -This chapter describes how to cross compile DPDK for ARM64 from x86 build hosts.
> +Cross compile DPDK for aarch64 and aarch32
> +==========================================
> +This chapter describes how to cross compile DPDK for aarch64 from x86 build hosts and compile
> +32-bit aarch32 DPDK from aarch64 build hosts.
>  
>  .. note::
>  
> -   Whilst it is recommended to natively build DPDK on ARM64 (just
> -   like with x86), it is also possible to cross-build DPDK for ARM64. An
> -   ARM64 cross compile GNU toolchain is used for this.
> +   Whilst it is recommended to natively build DPDK on aarch64 (just
> +   like with x86), it is also possible to cross-build DPDK for aarch64.
> +   An aarch64 cross compile GNU toolchain is used for this.
>  
>  Obtain the cross tool chain
>  ---------------------------
> @@ -88,18 +89,33 @@ To install it in Ubuntu::
>  
>     sudo apt-get install pkg-config-aarch64-linux-gnu
>  
> +.. note::
> +
> +    Some aarch64 platforms support EL0 aarch32 mode, which means the 32-bit aarch32 applications
> +    can run on aarch64. The armhf architecture toolchain ``gcc-arm-linux-gnueabihf`` is required
> +    for aarch32 on aarch64. To install it in Ubuntu::
> +
> +       sudo dpkg --add-architecture armhf
> +       sudo apt-get update
> +       sudo apt-get install -y gcc gcc-arm-linux-gnueabihf libc6:armhf make binutils
> +

Is 'make' still needed?  I don't run Ubuntu, so I'm not sure.

>  To cross-compile DPDK on a desired target machine we can use the following
>  command::
>  
>  	meson cross-build --cross-file <target_machine_configuration>
>  	ninja -C cross-build
>  
> -For example if the target machine is arm64 we can use the following
> +For example if the target machine is aarch64 we can use the following
>  command::
>  
>  	meson arm64-build --cross-file config/arm/arm64_armv8_linux_gcc
>  	ninja -C arm64-build
>  
> +If the target machine is aarch32 we can use the following command::
> +
> +	meson arm32-build --cross-file config/arm/arm32_armv8a_linux_gcc
> +	ninja -C arm32-build
> +
>  Configure and Cross Compile DPDK using Make
>  -------------------------------------------
>  To configure a build, choose one of the target configurations, like arm64-dpaa-linux-gcc and arm64-thunderx-linux-gcc.