Notes: Towards developing with ECL on a Samsung Chromebook

Overview: The Samsung Chromebook

• Samsung Chromebook model XE303C12-A01US
• Available at BestBuy
• Affordable PC platform, running ChromeOS 
• ChromeOS: Branded edition of ChromiumOS
• Linux kernel
• X.org display server
• Chromium OS security model
• Resource: Security Overview,  The Chromium Projects
• CPU: Samsung Exynos 5 Dual  SoC (ARM Cortex A15 / armv7l) 
• Minimal power consumption on DC power supply 
• may provide up to 9 hours PC runtime with wifi disabled and no USB devices connected
• may provide aprpox. 6 hours PC runtime with wifi activated and no USB devices connected 
• approx 2 hour charge time (YMMV)
• Ultrathin notebook
• SSD internal storage (16 GB) (eMMC interface may be available via Linux kernel)
• Internal storage extensible via built-in SD card reader and USB
• Supports USB 3.0 "SuperSpeed" devices 
• USB 3.0 is backwards compatible onto USB protocols 2.0, 1.x
• Resource: "10 things you should know about USB 2.0 and 3.0", TechRepublic
• In Chromebook "developer mode," a Chromebook can run an individual Linux chroot environment, on top of ChromeOS
• Resource: "How to Install Ubuntu Linux on Your Chromebook with Crouton", How-To Geek
• Resource: Crouton source code repository, Github
• Dual-boot system can be configured with ChrUbuntu
• May not support some features available directly on ChromeOS (e.g Adobe Flash)
• K Desktop Environment on Chromebook, "Is possible."
• Chroot on Samsung Chromebook uses Ubuntu ARM port
• Resource: ARM, Ubuntu Wiki

Overview: ANSI Common Lisp (CLtL2) on ARM

• CCL
• Uses CCL's FFIGEN4 (fork of FFIGEN) in developing CCL interfaces onto OS machine code
•  Resource: Obtaining and building the FFI translator (FFIGEN), CCL Wiki
• Resource: Building Framework Interfaces, CCL Wiki
• Does not run "out of the box" on Samsung Chromebook
• "CPU doesn't support required features"
• Patch available (?), must be cross-compiled
• Cross Compiling, CCL Wiki
• Alternate representation:

  ;; arm-xcompile.lisp
  
  (in-package #:ccl)
  
  ;; referencing lib/compile-ccl.lisp
  (eval-when (:compile-toplevel :load-toplevel :execute)
     (defparameter *arm-compiler-modules*
        '(arm-arch
            armenv
            arm-asm
            arm-lap
            ))
  
     (defparameter *arm-compiler-backend-modules*
        '(arm-backend arm-vinsns arm2))
  
     (defparameter *arm-xdev-modules* '(arm-lapmacros ))
  
     )
  
  
  
  ;; referencing
  ;; http://trac.clozure.com/ccl/wiki/CrossCompiling
  
  (require-update-modules *arm-compiler-modules* t)
  (require-update-modules *arm-compiler-backend-modules* t)
  (require-update-modules *arm-xdev-modules* t)
  (defpackage "ARM-LINUX")
  (load "ccl:lib;ffi-linuxarm")
  (require-update-modules *arm-xload-modules* t)
  (setup-arm-ftd (find-backend :linuxarm))
  
  
  (defun cl-user::do-xcompile ()
    (cross-xload-level-0 :linuxarm :force)
    (cross-compile-ccl :linuxarm t))
  
  

• CCL, in successfully evaluating the lisp form

  (cross-compile-ccl :linuxarm t)

  will generate a file, arm-boot (How to build into armcl* ?)
• SBCL
• ARM ports available
• sbcl-arm, repository at Github 
• Must be cross-compiled
• GCL
• Available via Ubuntu ports repository for armel
• ECL
• Available via Ubuntu ports repository for armel
• ABI / FFI interface (host OS): libffi 
• documentation available in TeXinfo format: 
• libffi source code, doc subdirectory
• published as HTML documentation in Debian package libffi-dev (Ubuntu  12.04 armel architecture)
• For documentation about the Lisp interface to FFI in ECL, see also:
•  ECL Manual, Section II, Chapter, 3, Foreign Function Interface
• Static FFI and Dynamic FFI
• For developing Static FFI interfaces, assistance is available for the developer, via the function FFI:C-INLINE
• For portable FFI, see also: 
• UFFI
• UFFI documentation in ECL manual
• CFFI
• CFFI Project page
• Implementation support in CFFI - notes about ECL:
• Differing semantics for loading of non-Lisp machine code libraries when #-:DFFI T .... i.e (not (uiop/os:featurep :dffi))
• No built-in :long-long type
• Unicode support not enabled by default
• McCLIM fork for ECL, Github
• Current status: "No multiple-value SETF" (Multiple-value SETF developed locally, using define-setf-expander.  Regression testing framework needed -- therefore, a substantial design decision onto the fork.)

Overview: Developing ECL for multiple hardware architectures, on the Linux platform

• Recommendation: Build ECL distribution packages from Ubuntu repository source packages 
• Possible relevance / use cases:
• Context: Software distribution and OS imaging
• Develop an ECL "back-port" for a single Debian-based Linux OS distribution 
• Distribute ECL development packages, while developing ECL
• Context: ECL development
• Install build-dependencies for ECL
• Cross-compile ECL
• Shell command (without cross-compile)

  export V=13.5.1+dfsg2 &&
      export DV=ecl-${V} &&
      export PV=ecl_${V}-4.1ubuntu1_i386 &&
      apt-get source ecl && 
      sudo aptitude build-dep ecl &&
      cd ${DV} &&
      debuild -uc -us -b &&
      sudo dpkg -i ../${PV}.deb
  

• Multi-architecture development in Debian GNU Linux and Debian-based Linux distributions
• Resource: Debian Multiarch HOWTO, Debian Wiki
• Resource: Guidelines for cross-build friendly packages, Debian Wiki
• Resource: Multiarch Architecture Specifiers (Tuples), Debian Wiki

"YMMV"