Re: [Qemu-ppc] [PATCH v2 0/3] Sam460ex emulation

[BALATON Zoltan]

On Sat, 17 Feb 2018, Thomas Huth wrote:
> On 16.02.2018 11:55, BALATON Zoltan wrote:
> > On Fri, 16 Feb 2018, Thomas Huth wrote:
> > > On 15.02.2018 22:27, BALATON Zoltan wrote:
> > > > Remaining patches for Sam460ex emulation. The original cover letter
> > > > with more details is here:
> > > >
> > > > http://lists.nongnu.org/archive/html/qemu-ppc/2017-08/msg00112.html
> > > >
> > > > We'll need to also add binaries for firmware (customised u-boot
> > > > version) and dtb but I'm not sure how to submit those.
> > >
> > > For the dtb, I think you could simply provide a patch that adds the dts
> > > file to the pc-bios directory and another one that adds the dtb. Just
> > > like it is already done with pc-bios/bamboo.dts / pc-bios/bamboo.dtb.
> >
> > OK thanks, I'll do that. Does it have to be two separate patches?
>
> I don't think so, I just thought that would be cleaner ... but one patch
> should be fine, too, I guess. David?
>
> > > For u-boot, can you use the same upstream level as e500 ? I.e. check
> > > whether "git submodule status roms/u-boot" is fine for you? If that's
> > > ok, just do a "git submodule update roms/u-boot" and build uboot from
> > > that directory - you then can submit a binary patch with that file for
> > > pc-bios, too.
> > >
> > > In case you need another u-boot version, I think you've got to update
> > > the submodule to the newer upstream version first, and then also rebuild
> > > the e500 binary... Cumbersome, but that's necessary since we've got to
> > > ship the u-boot sources in the QEMU release tarballs, too, to be
> > > compliant with the GPL.
> >
> > Unfortunately we can't use the same u-boot as e500 because this board
> > uses a forked and patched version which is not in upstream u-boot and
> > upstream u-boot has even dropped support for this CPU in latest version
> > so we actually need an older version (with patches) and not a newer one.
>
> That's very unfortunate ... any chance that you could try to get that
> CPU activated in upstream u-boot again and get the patches included there?

Not likely because it was removed to simplify code and get rid of 
unmaintained CPUs. Also the hardware vendor never upstreamed the board 
code which only exists in their sources, but these u-boot modifications 
are needed for boot loaders running on the hardware so we cannot use stock 
u-boot if we want to boot usual OSes which we want as that's the 
interesting part of this hardware.

Regards,
BALATON Zoltan

> > Therefore, it needs to be a binary built from a separate source so I
> > think a new submodule will need to be added for this. How to do that?
> > Where to host this git repo? Should I put it on github and refer to that
> > as an external repo or should it be hosted in qemu repo somehow?
>
> No clue ... adding Stefan and Jeff to CC:, maybe they can recommend
> something here.
>
> Thomas