Build the PetaLinux Image
=========================

Prerequisites
-------------

* PetaLinux Tools 2021.1

* Linux host machine

Build Flow Tutorial
-------------------

.. note::

   The below steps use platform vck190_mipiRxSingle_hdmiTx as an example. The same steps can be used for
   other platforms as well. The file/directory names will be replaced with the targeted platform name - *vck190_<plarform_name>*


#. Clone the VCK190 Base TRD repository using the following command

   .. code-block:: bash

      git clone --branch 2021.1 --recursive https://github.com/Xilinx/vck190-base-trd.git
      
The directory structure is described in the Introduction Section


**Generate PetaLinux Image**

Petalinux build flow has dependecy on artifacts from Vitis platform and overlay.
Build steps shown below before generating a bootable petalinux image.

* Section 4.2: **Create the Vitis Platform**

https://xilinx.github.io/vck190-base-trd/2021.1/html/build-pfm.html#create-the-vitis-platform

* Section 4.3: **Integrate Kernels in the Platform**

https://xilinx.github.io/vck190-base-trd/2021.1/html/build-filter2d.html#integrate-2d-filter-kernels-in-the-platform

The xsa and xclbin binaries produced from the previous step are consumed by 
petalinux during the image creation step.

#. Source the PetaLinux tool settings.sh script.

#. Create a bootable SD card image:

   .. code-block:: bash

	make sdcard PFM=vck190_mipiRxSingle_hdmiTx OVERLAY=filter2d

The resulting build artifacts will be available in the *images/linux/* folder.
The following is a list of important output files:

* **binary_container_1.xclbin**: This is the kernel meta data file used by XRT

* **BOOT.BIN**: This is the boot image which includes:

  * Platform Loader and Manager (PLM)

  * PS Management (PSM) firmware

  * Platform Device Image (PDI)

  * ARM trusted firmware

  * u-boot

  * Device tree blob

  * Merged AI Engine application and configuration data object (CDO) file

* **boot.scr**: A u-boot boot script

* **Image**: Linux kernel image

* **ramdisk.cpio.gz.u-boot**: Initial filesystem in ramdisk 

* **rootfs.tar.gz**: Compressed root file system tar ball

* **petalinux-sdimage.wic.xz**: Compressed SD card image file in wic format

The SD card image is now ready to be used to boot the device into Linux, see
Section *Run the Prebuilt Image* for details.

Steps to Custom configure a PetaLinux project and build
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

User can configure BSP with custom XSA file, refer to the steps provided in 

https://github.com/Xilinx/vck190-base-trd/blob/2021.1/petalinux/xilinx-vck190-base-trd/README.md

Reference 
---------
Petalinux Tools Documentation 

https://www.xilinx.com/support/documentation/sw_manuals/xilinx2021_1/ug1144-petalinux-tools-reference-guide.pdf

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Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
except in compliance with the License.

You may obtain a copy of the License at
[http://www.apache.org/licenses/LICENSE-2.0](http://www.apache.org/licenses/LICENSE-2.0)


Unless required by applicable law or agreed to in writing, software distributed under the
License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
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