Arch/mips/kernel/vpe.c

Arch/mips/kernel/vpe.c

[KokHow.Teh]

Hi;
	I am working on MIPS34KC with APRP kernel and I use uclibc
gccc-3.4.4 to build applications to run on VPE1. The present
implementation of VPE loader is limited to a few relocation types which
are used when mips_sde compiler is used. However, the relocatable binary
churn out from my uclibc-gcc-3.4.4 has more other relocation types than
the ones defined in arch/mips/kernel/vpe.c, especially those with GOT
relocation types. I have taken a look at the System V ABI Third Edition
but if anybody has any code reference and pointers to how each
relocation types should be implemented in C-code, it would be very
helpful.
	Thanks.

Regards,
KH

Arch/mips/kernel/vpe.c

[KokHow.Teh]

Hi;
	I am working on MIPS34KC with APRP kernel and I use uclibc
gccc-3.4.4 to build applications to run on VPE1. The present
implementation of VPE loader is limited to a few relocation types which
are used when mips_sde compiler is used. However, the relocatable binary
churn out from my uclibc-gcc-3.4.4 has more other relocation types than
the ones defined in arch/mips/kernel/vpe.c, especially those with GOT
relocation types. I have taken a look at the System V ABI Third Edition
but if anybody has any code reference and pointers to how each
relocation types should be implemented in C-code, it would be very
helpful.
	Thanks.

Regards,
KH

Re: Arch/mips/kernel/vpe.c

[Thiemo Seufer]

KokHow.Teh@infineon.com wrote:
> Hi;
> 	I am working on MIPS34KC with APRP kernel and I use uclibc
> gccc-3.4.4 to build applications to run on VPE1. The present
> implementation of VPE loader is limited to a few relocation types which
> are used when mips_sde compiler is used. However, the relocatable binary
> churn out from my uclibc-gcc-3.4.4 has more other relocation types than
> the ones defined in arch/mips/kernel/vpe.c, especially those with GOT
> relocation types. I have taken a look at the System V ABI Third Edition
> but if anybody has any code reference and pointers to how each
> relocation types should be implemented in C-code, it would be very
> helpful.

The most likely place to look at would be the binutils source code. That
said, you can probably get away without enhancing the VPE loader by using
  a) fully linked (non-relocatable) executables, or
  b) non-PIC code, like SDE does

Regardless of your choice, you will have to make sure the uclibc toolchain
doesn't use any libraries which need Linux facilities, as the bare-metal
environment on VPE1 doesn't provide them. For that reason I believe you
are better of with SDE or a similiar mips*-elf configured toolchain.


Thiemo

Re: Arch/mips/kernel/vpe.c

[Ralf Baechle]

On Sat, Jan 05, 2008 at 05:05:46PM +0000, Thiemo Seufer wrote:

> > 	I am working on MIPS34KC with APRP kernel and I use uclibc
> > gccc-3.4.4 to build applications to run on VPE1. The present
> > implementation of VPE loader is limited to a few relocation types which
> > are used when mips_sde compiler is used. However, the relocatable binary
> > churn out from my uclibc-gcc-3.4.4 has more other relocation types than
> > the ones defined in arch/mips/kernel/vpe.c, especially those with GOT
> > relocation types. I have taken a look at the System V ABI Third Edition
> > but if anybody has any code reference and pointers to how each
> > relocation types should be implemented in C-code, it would be very
> > helpful.
> 
> The most likely place to look at would be the binutils source code. That
> said, you can probably get away without enhancing the VPE loader by using
>   a) fully linked (non-relocatable) executables, or
>   b) non-PIC code, like SDE does
> 
> Regardless of your choice, you will have to make sure the uclibc toolchain
> doesn't use any libraries which need Linux facilities, as the bare-metal
> environment on VPE1 doesn't provide them. For that reason I believe you
> are better of with SDE or a similiar mips*-elf configured toolchain.

I'm tempted to replace the existing vpe loader with something like the 2.4
version of insmod which does all the relocation handling in userspace and a
device file which make the vpe memory available to userspace for the loader
to write to.  Or something like spufs.

  Ralf