LinuxBIOS debugging with an emulator

Stephen.Kimball at bench.com Stephen.Kimball at bench.com
Thu Oct 28 16:41:00 CEST 2004


> On Tue, 26 Oct 2004 Stephen.Kimball at bench.com wrote:
> > 
> > Can someone tell me what the starting sequence is with LinuxBIOS?
> > 
> > Reset jumps to crt0.s.  crt0.s calls auto.E.  auto.E is built using
> > romcc, so source-level debugging is not possible.  
>
> ah well :-)
>
> > The statement
> > locations can be found using the Lxxxx labels in linuxbios.map.
Then
> > hardwaremain is called. Hardwaremain is the first C function called.
>
> yep.
>
> > Crt0 and auto run out of FLASH.  Hardwaremain is the first function
> > called after LinuxBIOS is copied to RAM.
>
> sounds good so far.
>
> ron

It seems that LinuxBIOS copies itself to _RAMBASE, which is 0x4000.
Then it branches to 0x4000 into _start, which sets up the stack and
calls hardwaremain.  The address of hardwaremain from linuxbios_c.o is
wrong.  The address is not the Flash address and it's not the RAM
address.  Can someone explain how linuxbios_c.o is linked with RAM
addresses?  

Steve 



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