[v12,2/6] doc: add a guide doc for cross compiling from x86

  From: gavin hu <gavin.hu@arm.com>

This is the guide for cross compiling ARM64 DPDK from X86 hosts.

Signed-off-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Steve Capper <Steve.Capper@arm.com>
Reviewed-by: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
Acked-by: Marko Kovacevic <marko.kovacevic@intel.com>
---
 .../linux_gsg/cross_build_dpdk_for_arm64.rst       | 137 +++++++++++++++++++++
 doc/guides/linux_gsg/index.rst                     |   1 +
 2 files changed, 138 insertions(+)
 create mode 100644 doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst
  

-----Original Message-----
> Date: Tue, 19 Jun 2018 18:36:53 +0800
> From: Gavin Hu <gavin.hu@arm.com>
> To: dev@dpdk.org
> CC: nd@arm.com, gavin.hu@arm.com
> Subject: [dpdk-dev] [PATCH v12 2/6] doc: add a guide doc for cross
>  compiling from x86
> X-Mailer: git-send-email 2.11.0
> 
> 
> From: gavin hu <gavin.hu@arm.com>
> 
> This is the guide for cross compiling ARM64 DPDK from X86 hosts.
> 
> Signed-off-by: Gavin Hu <gavin.hu@arm.com>
> Reviewed-by: Steve Capper <Steve.Capper@arm.com>
> Reviewed-by: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
> Acked-by: Marko Kovacevic <marko.kovacevic@intel.com>


There is a build warning. Please check it
➜ [master][dpdk.org] $ make  doc-guides-html
sphinx processing guides-html...
/export/dpdk.org/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst:133: WARNING: Unexpected indentation.


> ---
>  .../linux_gsg/cross_build_dpdk_for_arm64.rst       | 137 +++++++++++++++++++++
>  doc/guides/linux_gsg/index.rst                     |   1 +
>  2 files changed, 138 insertions(+)
>  create mode 100644 doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst
> 
> diff --git a/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst b/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst
> new file mode 100644
> index 000000000..551f0aef8
> --- /dev/null
> +++ b/doc/guides/linux_gsg/cross_build_dpdk_for_arm64.rst
> @@ -0,0 +1,137 @@
> +..  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.
> +
> +.. 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.
> +
> +Obtain the cross tool chain
> +---------------------------
> +The latest cross compile tool chain can be downloaded from:
> +https://releases.linaro.org/components/toolchain/binaries/latest/aarch64-linux-gnu/.

A newline is better here for readability in rendered html file.

> +Following is the step to get the version 7.2.1, latest one at the time of this writing.
> +
> +.. code-block:: console
> +
> +   wget https://releases.linaro.org/components/toolchain/binaries/latest/
> +   aarch64-linux-gnu/gcc-linaro-7.2.1-2017.11-x86_64_aarch64-linux-gnu.tar.xz

Please make this single line for easy access to URL in  rendered html. 

> +
> +Unzip and add into the PATH
> +---------------------------
> +
> +.. code-block:: console
> +
> +   tar -xvf gcc-linaro-7.2.1-2017.11-x86_64_aarch64-linux-gnu.tar.xz
> +   export PATH=$PATH:<cross_install_dir>/gcc-linaro-7.2.1-2017.11-x86_64
> +   _aarch64-linux-gnu/bin

Please make this single line for easy access to URL in  rendered html. 

> +
> +.. note::
> +
> +   For the host requirements and other info, refer to the release note section:
> +   https://releases.linaro.org/components/toolchain/binaries/latest/
> +
> +Getting the prerequisite library
> +--------------------------------
> +
> +NUMA is required by most modern machines, not needed for non-NUMA architectures.
> +
> +.. note::
> +
> +   For compiling the NUMA lib, run libtool --version to ensure the libtool version >= 2.2,
> +   otherwise the compilation will fail with errors.
> +
> +.. code-block:: console
> +
> +   git clone https://github.com/numactl/numactl.git
> +   cd numactl
> +   git checkout v2.0.11 -b v2.0.11
> +   ./autogen.sh
> +   autoconf -i
> +   ./configure --host=x86_64 CC=aarch64-linux-gnu-gcc prefix=<numa install dir>
> +   make install
> +
> +The numa header files and lib file is generated in the include and lib folder respectively under <numa install dir>.
> +
> +.. _argment_the_cross_toolcain_with_numa_support:

s/toolchin/toolchain

> +
> +Augment the cross toolchain with NUMA support
> +---------------------------------------------
> +
> +.. note::
> +
> +   This way is optional, an alternative is to use extra CFLAGS and LDFLAGS, depicted in :ref:`configure_and_cross_compile_dpdk_build` below.
> +
> +Copy the NUMA header files to the cross compiler's include directory:
> +
> +.. code-block:: console
> +
> +   cp <numa_install_dir>/include/numa*.h <cross_install_dir>/gcc-linaro-7.2.1-2017.11
> +   -x86_64_aarch64-linux-gnu/bin/../aarch64-linux-gnu/libc/usr/include/

Please make this single line for easy access in rendered html. 

> +   cp <numa_install_dir>/lib/libnuma.a <cross_install_dir>/gcc-linaro-7.2.1-2017.11
> +   -x86_64_aarch64-linux-gnu/lib/gcc/aarch64-linux-gnu/7.2.1/

Please make this single line for easy access in rendered html. 

> +
> +.. _configure_and_cross_compile_dpdk_build:
> +
> +Configure and cross compile DPDK Build
> +--------------------------------------
> +To configure a build, choose one of the target configurations, like arm64-dpaa2-linuxapp-gcc and arm64-thunderx-linuxapp-gcc.
> +
> +.. code-block:: console
> +
> +   make config T=arm64-armv8a-linuxapp-gcc
> +
> +To cross-compile, without compiling the kernel modules, use the following command:
> +
> +.. code-block:: console
> +
> +   make -j CROSS=aarch64-linux-gnu- CONFIG_RTE_KNI_KMOD=n CONFIG_RTE_EAL_IGB_UIO=n
> +
> +To cross-compile, including the kernel modules, the kernel source tree needs to be specified by setting
> +RTE_KERNELDIR:
> +
> +.. code-block:: console
> +
> +   make -j CROSS=aarch64-linux-gnu- RTE_KERNELDIR=<kernel_src_rootdir>
> +   CROSS_COMPILE=aarch64-linux-gnu-
> +
> +To compile for non-NUMA targets, without compiling the kernel modules, use the following command:
> +
> +.. code-block:: console
> +
> +   make -j CROSS=aarch64-linux-gnu- CONFIG_RTE_KNI_KMOD=n CONFIG_RTE_EAL_IGB_UIO=n
> +   CONFIG_RTE_LIBRTE_VHOST_NUMA=n CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES=n

Please make this single line for easy access in rendered html. 

> +
> +.. note::
> +
> +   1. EXTRA_CFLAGS and EXTRA_LDFLAGS should be added to include the NUMA headers and link the library respectively,
> +   if the above step :ref:`argment_the_cross_toolcain_with_numa_support` was skipped therefore the toolchain was not

s/toolcain/toolchain

> +   argmented with NUMA support.

augmented??

> +
> +   2. "-isystem <numa_install_dir>/include" should be add to EXTRA_CFLAGS, otherwise the numa.h file will get a lot of compiling
> +   errors of Werror=cast-qual, Werror=strict-prototypes and Werror=old-style-definition.
> +
> +   An example is given below:
> +
> +   .. code-block:: console
> +
> +      make -j CROSS=aarch64-linux-gnu- CONFIG_RTE_KNI_KMOD=n CONFIG_RTE_EAL_IGB_UIO=n
> +      EXTRA_CFLAGS="-isystem <numa_install_dir>/include" EXTRA_LDFLAGS=
> +      "-L<numa_install_dir>/lib -lnuma"

Please make this single line for easy access in rendered html. 

> +
> +Meson Cross Compiling DPDK
> +--------------------------
> +
> +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
> +command::
> +       meson arm-build --cross-file config/arm/arm64_armv8_linuxapp_gcc

s/arm-build/arm64-build??

ninja -C arm64-build/ step is missing.



> diff --git a/doc/guides/linux_gsg/index.rst b/doc/guides/linux_gsg/index.rst
> index 2a7bdfe92..077f93023 100644
> --- a/doc/guides/linux_gsg/index.rst
> +++ b/doc/guides/linux_gsg/index.rst
> @@ -13,6 +13,7 @@ Getting Started Guide for Linux
>      intro
>      sys_reqs
>      build_dpdk
> +    cross_build_dpdk_for_arm64
>      linux_drivers
>      build_sample_apps
>      enable_func
> --
> 2.11.0
>