1. 1 THE ARCHITECTURE FOR THE DIGITAL WORLD TM THE ARCHITECTURE FOR THE DIGITAL WORLD Philippe.Robin@arm.com Embedded Linux for ARM Architecture

2. 2 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Summary System overview Strategy Technical challenges GNU roadmap Board support Linux vendors Resources

3. 3 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Main Components Hardware Kernel Milo Network Applications X11, Qt,Microwindows, Networking Utilities etc... Milo (BIOS equivalent) Initialises the board Start kernel execution Based on AFS 1.4.x Kernel Configurable includes drivers and modules Applications Filesystem image (cramfs…) Reside in Flash or cross-mounted directory via NFS Imported packages Hardware Integrator AP or CP ARM Core + Logic modules

4. 4 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Linux Kernel Support for ARM cores with MMU ARM 720, 92x, 102x, 113x Most options are configurable using graphical tool Pre-defined configurations for selected boards Two main versions: 2.4.x (currently 2.4.19 rmk6) 2.5.x leading to 2.6 kernel (planned end 2003) Availability: base kernel source (open source and DevZone) ARM additional patches rmk i (open source: http://www.arm.uk.linux.org ) ARM specific patches (DevZone)

5. 5 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Applications Filesystem containing system utilities and applications Packages can be selected at build time using configuration tool Import packages publicly available (i.e. Debian)Debian ARM DevZone contains: Pre-built images Tools and packages to build filesystem images

6. 6 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Development Environment Based on Linux host platforms Use GNU cross compiler (also available on ARM DevZone)GNU ARM Development tools can be used to: Load Kernel images using ARM Debugger with ICE tools Symbolic debug of kernel images or drivers (using breakpoints, trace etc.) GDB used to debug applications

7. 7 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Linux Strategy Based on open source and standards Contribute new code back to open source  http://www.arm.uk.linux.org Provide support for ARM evaluation boards Add support for new ARM cores (e.g. ARM10x, ARMv6) Develop and validate new functionality (energy management, security…) Used internally for system validation (cores and boards) Partner support via ARM DevZone

8. 8 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Linux Strategy Work with OEMs creating products using Linux Work with Embedded Linux companies Offer comprehensive support for kernels, applications and development environment ARM DevZone used as focal point of contact ARM connected community program

9. 9 THE ARCHITECTURE FOR THE DIGITAL WORLD TM ARMv6 support Full ARMv6 support with 2.6 kernel Includes kernel optimisations to exploit ARMv6 architecture 2.4 kernel patch to run legacy code Early availability via patches on DevZone Aligned with 2.6 kernel release and hardware availability Used with GNU development toolchain supporting new v6 instructions (binutils initially)

10. 10 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Technical challenges (1) Reduced memory footprint Modular kernel Library size Multiple choices of libraries such as GNU C library. Support for non-MMU cores Linux only runs on cores with Memory Protection Unit uCLinux Adapted version of Linux to run on non-MMU cores Uses different libraries

11. 11 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Technical challenges (2) Thumb support Reduced memory footprint Security Support for encryption Use of specialised hardware features Power management Advanced Configuration and Power Interface (APCI) Intelligent Energy management (IEM) (hardware and software support)

12. 12 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Technical challenges (3) Symmetric Multi-Processor Synchronization issues Memory coherence Toolchain support Expose kernel resources to the debugger Halted System Debug Running System Debug System profiling Kernel profiling Use Trace Macrocell capabilities

13. 13 THE ARCHITECTURE FOR THE DIGITAL WORLD TM GNU Roadmap GCC 2.95.3 Stabilized version APCS PE Coff/ Elf Dwarf GCC 3.2.x ATPCS ARM Architecture 5T (VFP) Xscale Next release based GCC 3.x Support ARM Architecture 6

14. 14 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Board support Integrator/CM Core Modules CM7TDMI CM740T CM720T CM940T CM920T-ETM CM946E-S CM966E-S CM10200 CM926EJ-S Integrator/AM Analyzer Module Integrator/LM Logic Modules LM-XCV2000E LM-EP20K600E Integrator/AP ASIC Development Platform Integrator/CP Compact Platform Integrator/PP Porting Platforms Integrator/IM Interface Modules Integrator/LT Logic Tile LT-XC2V6000 IM-LT1

15. 15 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Main Linux vendors Montavista http://www.mvista.com Metrowerks http://www.metrowerks.com LynuxWorks http://www.lynuxworks.com Lineo http://www.lineo.co.jp

16. 16 THE ARCHITECTURE FOR THE DIGITAL WORLD TM Additional resources http://www.kernel.org http://www.armdevzone.com http://www.arm.uk.linux.org http://www.gnu.org http://www.uclinux.org http://www.mvista.com http://www.metrowerks.com http://www.lynuxworks.com http://www.lineo.co.jp http://www.openpda.com http://www.trolltech.com