ARMevaluationAELALIP

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 * Pull alip-ael sources into local archive.  * Pull alip-ael source packages from ubuntu into local archive.

Summary

ARM uses various linux file system images. This spec explores how these might be supplied from Ubuntu.

Release Note

An archive of the ALIP-AEL software stack can now be built for ARM architectures ARMv5 & ARMV6 using Ubuntu packages and associated tools. This method can be extended for the remaining packages of the full distribution, provided any dependency loops are broken and packages are well behaved under cross compilation.

Rationale

If Ubuntu is used from the very beginning of involvement with ARM it's more likely to be used for further activities. All initial examples of linux based systems provided by ARM Ltd. would tend to be Ubuntu based systems.

User stories

  • New Architecture: ARM designers design a new architecture. They package a GNU cross compilation toolchain for the architecture. They can now use the available tools to cross build a complete, or partial, system image. This both exercises the toolchain, provides a basis for demonstrating the architectures benefits and provides the build-essential packages required to build (bootstrap) the complete archive for the new architecture.

  • Development: ARM Ltd. developers want to develop a new BSP, tool or other software package. Pulling an original ALIP-AEL archive from Ubuntu they can use xdeb to quickly put their package into this & iterate builds for development.

  • uClinux To demonstrate an MMUless core ARM Ltd. developers pull a minimal uClinux system image from Ubuntu and boot it on their target.
  • Compiler Validation: To validate non-standard compiler options (including architectures) a partial, or complete, archive is rebuilt with a compiler defaulting to those options.
  • Demo: User supplied binary packages can be inserted into the ALIP-AEL software stack image with minimal effort.
  • Ship: ARM supplied development boards can be shipped with an installer or debootstrap style image which boots an ALIP-AEL stack with the ability to install further packages from the Ubuntu or related archives.

In the current cycle only the Compiler Validation use case will be satisfied, using xdeb. This method will be used rather than repeated native builds for the separate architectures since this aids development of solutions for the other cases. Those cases - New Architecture, Development, Demo may be considered for inclusion in future cycles.

The ucLinux case will not be considered further as it is one example of the New Architecture use case.

Assumptions

Required tools are provided, in a timely fashion, by

Cross compilation GNU toolchain supplied by user in standard GNU/Ubuntu packaged form for use by the Ubuntu tools.

Design

The hardest use case is that of a complete new architecture. A roadmap to achieve this can be constructed:-

  • Compiler Validation Development Demo Ship New Architecture.

Implementation

Compiler Validation

  • Package toolchain with desired architecture as default into local archive.
  • Pull alip-ael source packages from ubuntu into local archive.
  • Use xdeb on the local archive to rebuild the alip-ael stack
    • Break any dependency loops locally
    • Fix any packages not cross compilation compliant (pushed upstream)
  • Build images from the local archive using the image building tool.

Development

Satisfied by the above.

Demo

Satisfied by the above.

Ship

Modify the ubuntu installer, if required, to access archives produced above

New Architecture

  • Produce build-essential packages using xdeb
  • Modify buildd to use xdeb
  • Move to native buildds as hardware becomes available.

Test/Demo Plan

Unresolved issues

Does the ubuntu installer require adapting to use incomplete archives, in the manner described above.

BoF agenda and discussion

Use this section to take notes during the BoF; if you keep it in the approved spec, use it for summarising what was discussed and note any options that were rejected.

CategorySpec

Specs/M/ARMevaluationAELALIP (last edited 2011-01-21 16:09:41 by fw-tnat)