This project introduces a set of yocto recipes (systemd service units, udev rules, and kernel module configurations) designed to dramatically reduce the time-to-first-perception for critical system services —

• Display (Weston / DRM pipeline)
• Audio (PipeWire)
• Camera (GStreamer / cam-server pipelines)

It targets use cases such as Action Cameras, Automotive IVI, and Industrial HMI where a very fast boot experience is a hard product requirement.

QuickBoot achieves early boot of critical services through three complementary techniques applied consistently across all three subsystems:

Rather than relying on udev coldplug (which is slow and non-deterministic), QuickBoot uses modules-load.d configuration files to pre-load kernel modules in a precise, dependency-ordered sequence during systemd-modules-load.service — one of the earliest systemd units to run.

Custom udev rules watch for specific device node creation events (e.g., controlC0 for ALSA, video0 for camera, card0 for DRM/display) and immediately trigger the corresponding service the moment the hardware is ready — eliminating polling delays.

All early boot services are configured with DefaultDependencies=no, which removes the implicit ordering after sysinit.target and basic.target. This allows services to start in parallel with the rest of the boot sequence, as soon as their hardware dependency is satisfied.

Goal: Play an audio chime as early as possible to signal boot completion.

Mechanism:

• audio-modules.conf pre-loads ALSA/audio kernel modules via systemd-modules-load before udev coldplug runs.
• A udev rule fires pipewire.service the instant controlC0 (the ALSA control device) appears.
• pipewire.service runs with DefaultDependencies=no, bypassing sysinit.target ordering.
• early_audio_play_app.service plays a WAV file to the pal_sink_speaker_ll low-latency sink and logs precise timestamps to both journald and /dev/kmsg for boot-time measurement.

Goal: Show a splash screen or UI frame as early as possible (before multi-user.target).

Mechanism:

• display-modules.conf pre-loads DRM/GPU kernel modules early.
• A udev rule fires 'weston.service' whenever DRM is ready ( dev-dri-card0.device )
• 'weston.service runs with DefaultDependencies=no, bypassing sysinit.target ordering.
• 'weston.service runs with --backend=drm-backend.so --shell=kiosk-shell.so --idle-time=0

Goal: Start camera preview (first frame) as fast as possible, targeting Action Camera use cases.

Mechanism:

• camera-modules.conf pre-loads camera and V4L2 kernel modules via systemd-modules-load.
• 02-cam-server.rules triggers cam-server.service the moment video0 is enumerated by udev.
• early_cam_preview_app.service is a real-time scheduled service that launches a GStreamer pipeline via cam_preview_app.sh on the Weston compositor.
• iq9075-first-boot-cam-setup.sh performs a one-time first-boot optimization: configures EFI settings and relocates unused sensor module binaries to reduce camera initialization latency on subsequent boots.

• Target device running Qualcomm Linux (QLI 2.0+)
• Root access on the target
• Weston, PipeWire, GStreamer installed on the rootfs

Clone the repository on the target device and run the installer:

git clone https://github.com/ctheegal/quickboot.git
cd quickboot
sudo ./quickboot-apps-installer.sh

The installer automatically:

1. Copies udev rules → /etc/udev/rules.d/
2. Copies *-modules.conf → /etc/modules.d/ and other .conf → /etc/modprobe.d/
3. Copies systemd service/socket units → /etc/systemd/system/
4. Copies shell scripts → /usr/bin/ (with execute permission)
5. Copies WAV audio assets → /usr/share/sounds/
6. Runs systemctl daemon-reload
7. Auto-discovers and enables all early_*.service units
8. Runs udevadm control --reload-rules && udevadm trigger

sudo reboot

After reboot, the early boot services will activate automatically as their respective hardware devices are enumerated.

• cd qcom-meta
• git clone https://github.com/ctheegal/quickboot

• meta-qcom-distro/recipes-products/images/qcom-multimedia-image.bb
• IMAGE_INSTALL:append = " quickboot_audio quickboot_camera quickboot_display"

• Chitti Babu Theegala — `ctheegal@qti.qualcomm.com, Qualcomm Technologies, Inc.
• Vaibhav Jindal — vaibjind@qti.qualcomm.com, Qualcomm Technologies, Inc.
• Tarun Balaji Nidiganti — tnidiganti@qti.qualcomm.com, Qualcomm Technologies, Inc.

Quickboot is licensed under the BSD-3-clause License. See LICENSE.txt for the full license text.