Building on top of an existing BSP
A Board Support Package (BSP) layer adds support for a particular hardware device or family of devices to Yocto. This support usually includes the bootloader, device tree blobs, and additional kernel drivers needed to boot Linux on that specific hardware. A BSP may also include any additional user space software and peripheral firmware needed to fully enable and utilize all the features of the hardware. By convention, BSP layer names start with the meta-
prefix, followed by the machine's name. Locating the best BSP for your target device is the first step toward building a bootable image for it using Yocto.
The OpenEmbedded layer index (https://layers.openembedded.org/layerindex) is the best place to start looking for quality BSPs. Your board's manufacturer or silicon vendor may also offer BSP layers. The Yocto Project provides a BSP for all variants of the Raspberry Pi. You can find the GitHub repository for that BSP layer and all the...