Re: Cross compiling MIPS kernel under x86

["Phil Staub" <phils@windriver.com>]

On Thu, 27 May 2010 14:34:09 -0700, David Daney <david.s.daney@gmail.com>  
wrote:
> On 05/27/2010 09:29 AM, octane indice wrote:
> > Response to Dmitri Vorobiev<dmitri.vorobiev@gmail.com>  :
> > > Just checked that the following steps result in a successful
> > > build of a vanilla 2.6.34 vmlinux:
> > Thanks for taking the time to do it.
> >
> > > http://ftp.gnu.org/gnu/gcc/gcc-4.4.4/gcc-core-4.4.4.tar.bz2
> > > tar jxf gcc-core-4.4.4.tar.bz2
> > > cd ../build
> > > ../src/gcc-4.4.4/configure --target=mips64-unknown-linux-gnu
> > > --prefix=/work/tmp/zoo --disable-threads --disable-shared
> > > --disable-multilib --disable-libgcc --disable-libmudflap
> > > --disable-libssp --disable-libgomp
> > > make
> > It fails here with something related to stdc++. With adding a
> > --enable-language=c it works. So the configure line I used is:
> > ../gcc-4.4.4/configure --target=mips64-unknown-linux-gnu
> > --prefix=/var/samba/mips --disable-threads --disable-shared
> > --disable-multilib --disable-libgcc --disable-libmudflap  
> > --disable-libssp
> > --disable-libgomp --enable-languages=c
> >
> > > make ARCH=mips cavium-octeon_defconfig
> > > make ARCH=mips
> > > CROSS_COMPILE=/work/tmp/zoo/bin/mips64-unknown-linux-gnu- vmlinux
> > >
> > > Hope that helps.
> > It helped me a lot, thank you. The kernel compiles fine.
> > The kernel is very huge: 39MBytes (!).
> > After a mips64-unknown-linux-gnu-strip, it downsized to 3.3MBytes.
> > But that kernel doesn't boot.
> >
> > The system in the board I have uses in U-boot:
> > ext2load ide 0 4000000 vmlinux
> > bootoctlinux 4000000 (other args..)
> >
> > But when I replace the vmlinux file with mine called 'mips', it says:
> > RSEC-K1# ext2load ide 0 4000000 mips
> >
> > 3362840 bytes read
> > WARNING: Data loaded outside of the reserved load area, memory  
> > corruption
> > may occur.
> > WARNING: Please refer to the bootloader memory map documentation for  
> > more
> > information.
> > RSEC-K1# bootoctlinux 4000000
> > ELF file is 64 bit
> > Attempting to allocate memory for ELF segment: addr: 0xffffffff81100000
> > (adjusted to: 0x0000000001100000), size 0x355c00
> > Allocated memory for ELF segment: addr: 0xffffffff81100000, size  
> > 0x355c00
> > Attempting to allocate memory for ELF segment: addr: 0xffffffff81343da0
> > (adjusted to: 0x0000000001343da0), size 0x24
> > Error allocating memory for elf image!
> > ## ERROR loading File!
> > RSEC-K1#
> Early Octeon bootloaders cannot handle PT_NOTE program headers, I think
> that is what is biting you here.
>
> If you can upgrade to an SDK-1.9 or later bootloader, I would recommend
> that.  Otherwise remove the PT_NOTE from your kernel image (the
> technique for doing this is left as an excise for the reader, but I have
> found that emacs hexl mode works well).
In the top level Makefile, you'll find this:


# Use --build-id when available.
LDFLAGS_BUILD_ID = $(patsubst -Wl$(comma)%,%,\
                              $(call cc-ldoption, -Wl$(comma)--build-id,))

Comment that out and it should fix you up.

Phil

> David Daney

--
Phil Staub, Senior Member of Technical Staff, Wind River
Direct: 702.290.0470 Fax: 702.982.0085