MPC5121 CodeWarrier relocatable output

[martinw]

Hi,


MPC5121 power pc, no OS (actually a port of an OS we wrote in-house for Coldfire)

I want to be able to read an application at boot time (from SD card) and relocate it to run at a memory address defined at run time.

My understanding of elf is that there is an option to produce a binary file that contains relocation tables etc.

Can anyone tell me if the CodeWarrier linker can produce the required elf format?

And where can I find the specification for the elf format that CodeWarrier generates?

Many thanks

Martin Wakely

[CrasyCat]

Hello

This can probably be implemented using PIC code.

CrasyCat

[martinw]

Will you explain what you mean by PIC code please?

[J2MEJediMaster]

PIC = Position Independent Code. The branch and jump instructions use relative addresses, rather than absolute addresses. This allows the program to be loaded just about anywhere in memory. Check the Build Tools manual and the Power Architecture Targeting Maunal for PIC/PID support. Search for the string "PIC/PID" in the Acrobat files of these manuals to get started.

---Tom

[martinw]

Thanks - I'll look that up.  For one (horrible) moment I thought it might be a Microchip reference

Cheers