On Wed, 1 Nov 2000, Chris Gilbert wrote:

> On Wed, 01 Nov 2000, Simon Burge wrote:
> > Dave Daniels wrote:
> > > What is the time schedule for switching to ELF format instead of
> > > a.out in NetBSD/arm32? I ask because the bootloader will almost
> > > certainly have to be modified to handle kernels which are in
> > > ELF format. If so, it should be added to the 'things to do'
> > > list.
> >
> > Not having looked at the internals of the arm32 bootloader(s), but
> > by using libsa's loadfile() you don't need to write any ELF specific
> > code - it's all there already.  For netbooting, you're usually
> > constrained by what format the firmware/PROM/BIOS understands.
>
> I don't believe that the bootloader for Acorn based hardware uses libsa (I
> may be wrong, and it'd be good to know)  All boots on currently supported
> acorn hardware goes into Riscos (no choice, it's where the roms are I think)
> The bootloader has to map things around.
>
> > In short - I wouldn't worry about this too much.
>
> Is there any major gain to doing so?
>
> Have we plans in the near future to switch to ELF? (by near I mean next
> release, 1.6?)
>
	It would make sense - ELF is the format best supported by the
	gnu toolchain.

> Wouldn't a move not require the kernel to be ELF, IE userland goes to elf,
> kernel is a.out, and then eventually moves to ELF.  eg 1.6 userland to elf,
> 1.7 kernel to elf?

	Kernel a.out/ELF is independent from the userland a.out/ELF -
	either kernel can be made to run a userland in either format.
	The only issue is ensuring the toolchain can compile both, or
	having a tool to convert the kernel format after compile.

	If I recall correctly the pmax and macppc port build ELF kernels
	and have a tool to convert them to ECOFF or whatever the builtin
	boot code requires.

	The arm26 port is already ELF, so it might make sense to look at
	getting the same bootloader to work on both platforms and handle
	ELF/a.out in the process.

	But yes, it would be good to go to ELF for 1.6, developer time
	permitting :)

                David/absolute
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