Current Software Specifications

Software Stack: From First Boot to Full Distribution

Note: This is an initial draft of the software roadmap for the PowerPC Notebook project. This should be treated as high level thinking for now to give us a starting point rather than as a finalized roadmap. Comments and contributions are welcome.  
Target architecture: PPC64 Big Endian.

Introduction

The software stack for the PowerPC Notebook is a critical enabler for the hardware. Our challenge is to bring up a modern, open-source Linux system on non-mainstream architecture (PowerPC), using a custom motherboard based on the NXP T2080 SoC (?). That means:

• Bootstrapping software from scratch, with limited upstream support  
  * Building and testing a minimal Linux system to prove hardware works  
  * Gradually evolving toward a user-friendly, maintainable Linux distribution  

We outline a progressive roadmap: from booting the board to building our own distro, using modern infrastructure and tools wherever possible.

1. Basic Plan: Booting the First Prototype

The first goal is to ensure our hardware can boot into a minimal Linux environment.

Why

• Validates CPU, memory, and power circuitry
• Enables testing and debugging of other peripherals
• Serves as foundation for OS bring-up and userland development

2. Essentials: Proving the Prototype Works

Once we can boot, we need a minimal userland to interact with the system.

=== Components Required ===

Goal

• Boot into a shell prompt
• Validate basic system resources (<code>/proc/cpuinfo</code>, <code>dmesg</code>, etc.)
• Confirm networking, storage, and peripheral availability  

3. Nice-to-Haves: Editors, Tools, and Utilities

Once the system is up, we add tools to support development, testing, and usability.

=== Suggested Additions ===

4. Distro: Building Our Own PowerPC Linux Distribution

Eventually, we want a user-facing Linux distribution specifically optimized for the PowerPC Notebook.

=== Building Blocks ===

Distro Build Systems to Consider

• debootstrap / live-build (Debian-based builds)
• Buildroot (for minimal rootfs + kernel images)
• Yocto Project (flexible meta-distribution)
• Gentoo Catalyst (for full ISO or stage builds)  

5. Reusing and Cross-compiling from Existing Distros

Before reinventing the wheel, we aim to reuse as much as possible from other PowerPC-supporting Linux distributions.

=== Sources of Reusable Packages ===
* Debian Ports: Many packages already built for PPC64 (Big Endian)  
* Gentoo PPC64: Source-based packages easily recompiled for our target  
* Void Linux PPC: Lightweight, musl or glibc-based  
* Buildroot: Embedded-focused, ideal for minimal images  
* Yocto layers/meta-ppc: Helpful BSPs and tooling  

Cross-compiling Approach

1. Use `powerpc64-linux-gnu-gcc` cross-toolchain  
2. Cross-compile Debian source packages or Gentoo ebuilds  
3. Create our own package repository (e.g., Debian-style repo or overlay FS)  
4. Validate on QEMU before deploying to real hardware  

=== Tools and Infrastructure ===

Goal: Reduce duplication, benefit from upstream security updates, and create a lean maintainable software stack.

6. CI/CD Pipelines and Build Infrastructure

To ensure maintainability, reproducibility, and collaboration, we aim to adopt continuous integration and modern DevOps practices.

CI/CD Goals

• Automatically build U-Boot, kernel, and rootfs images
• Run tests on emulated environments (QEMU PPC64)
• Deploy daily/weekly builds for community testing
• Detect regressions early and validate commits  

7. Docker Images for Build and Dev Environments

Pre-configured Docker images help developers build and test quickly across any host system.

Use Cases

• Build U-Boot or Linux kernel from any host
• Package testing in isolated environments
• Running PPC-specific tools in reproducible containers  

8. Inspirations from Debian and Other Projects

We aim to reuse and adapt ideas from existing projects to accelerate development.

Relevant Debian Practices

• Reproducible Builds
• Debian Ports infrastructure
• <code>live-build</code> and <code>debootstrap</code>  
• Debian Installer (<code>d-i</code>)  
• QA tools: lintian, piuparts, autopkgtest  

=== Related Projects to Watch ===
{| class="wikitable"
! Project !! Relevance
|-
| Debian PowerPC || Maintains PPC64 ports and packages
|-
| Void PPC || Maintains lightweight PPC builds
|-
| Gentoo PPC || Flexible, source-based PPC support
|-
| Yocto/OpenEmbedded || Board support packages and rootfs config
|-
| OpenPOWER Firmware || Future firmware replacement roadmap
|}

9. Build Tooling (WIP/Placeholders)

This section will document the exact steps, tools, and workflows needed to build every part of the software stack.

Build Tooling Overview

• Cross-toolchain setup (e.g. NXP SDK, crosstool-ng, LLVM)
• U-Boot build and customization
• Linux kernel configuration and build
• Root filesystem generation methods (debootstrap, Buildroot, Yocto)
• Build orchestration (Makefiles, shell scripts, CI runners)
• Packaging tools for our distro (dpkg, xbps, etc.)
• Secure image signing (U-Boot SPL, FIT images, secure boot)
• Emulator-based validation and test harnesses

Note: Details for each item will be populated progressively as we finalize architecture and test results.

10. Other Links and Resources

Technical Resources

• NXP T2080 Reference Manual  
  * Denx U-Boot Git  
  * Linux PowerPC Git  
  * Debian PowerPC Wiki  
  * Void PPC Project  
  
  

Community and Support

* Power Progress Community  
* PowerPC IRC/Matrix  
* OpenPOWER Foundation