Build System Overview

KAS Configuration Hierarchy

KAS is the primary build system. Configuration is composed by layering YAML fragments:

File	Description
kas/bsp-base.yaml	Base configuration for BSP builds; defines repos and core settings
kas/bsp-multi.yaml	Multiconfig builds (separate configs for initramfs and containers)
kas/scarthgap.yaml / kas/kirkstone.yaml	Yocto release-specific patches and branches
kas/machines/*.yaml	Per-machine configurations
kas/platforms/*.yaml	Platform-specific layer includes (sunxi, raspberrypi, etc.)
kas/with-workspace.yaml	Overlay for local pantavisor source development

Multiconfig Architecture

When using bsp-multi.yaml, builds use three separate multiconfigs to avoid TMPDIR conflicts:

Multiconfig	Purpose	Config file
default	Main image build	—
pv-initramfs-panta	Initramfs with musl libc	conf/multiconfig/pv-initramfs-panta.conf
pv-panta	Container builds	conf/multiconfig/pv-panta.conf

Each multiconfig should use a separate TMPDIR:

TMPDIR = "${TOPDIR}/tmp-${DISTRO_CODENAME}-${MULTICONFIG_NAME}-${MACHINE}"

Raspberry Pi Tryboot (rpi-tryboot)

The rpi-tryboot feature enables A/B boot partition support for Raspberry Pi, building a unified boot image supporting all RPi variants from a single build.

Configuration: kas/machines/rpi.yaml

Kernel Variant Multiconfigs

Multiconfig	Machine	Target
rpi-kernel.conf	raspberrypi	Pi 0/1
rpi-kernel7.conf	raspberrypi2	Pi 2/3 32-bit
rpi-kernel7l.conf	raspberrypi-armv7	Pi 4 32-bit
rpi-kernel8.conf	raspberrypi-armv8	Pi 3/4 64-bit
rpi-kernel_2712.conf	raspberrypi5	Pi 5

Each uses a separate TMPDIR: tmp-${DISTRO_CODENAME}-rpi-kernel-${MACHINE}.

Key Recipes

• recipes-pv/images/rpi-boot-image.bb — FAT32 boot partition with all kernel variants
• recipes-pv/images/rpi-bootsel.bb — Boot selector partition with autoboot.txt
• WKS file: wic/rpi-tryboot-ab.wks

Partition Layout

Partition 1 (bootsel):  FAT32 — autoboot.txt, bootcode.bin (A/B selector)
Partition 2 (boot_a):   FAT32 — kernels, DTBs, config.txt, initramfs
Partition 3 (boot_b):   FAT32 — same as boot_a (for A/B switching)
Partition 4 (root):     ext4  — rootfs with /trails/0 pvr state

Output Artifacts

• pantavisor-rpi.img.gz — Gzipped boot partition
• modules_<version>.squashfs — Per-kernel-version modules (e.g. modules_6.1.77-v8+.squashfs)
• firmware.squashfs — Shared firmware

Output Artifacts

Build outputs are in build/tmp-{codename}/deploy/images/{machine}/:

Artifact	Description
*.pvrexport.tgz	Pantavisor export bundles (main deployment artifact)
*.wic / *.wic.bz2	Complete disk images
pantavisor-initramfs-*.cpio.gz	Initramfs image
pantavisor-appengine-docker.tar	Docker image for manual appengine testing
pantavisor-appengine-distro-docker-x86_64-*.tar.gz	Self-contained test bundle: Docker images + test.docker.sh runner

Key Build Paths

Path	Description
build/workspace/sources/pantavisor/	Pantavisor source (workspace builds)
build/tmp-scarthgap/deploy/images/	Build outputs
recipes-containers/pv-examples/	Example container recipes
.github/configs/release/	KAS release machine configurations