[flashrom] [PATCH] Add support for SPARC (maybe).

[Stefan Tauner]

On Mon, 09 Feb 2015 23:19:11 +0100
Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006 at gmx.net> wrote:

> On 08.02.2015 22:16, Stefan Tauner wrote:
> > On Sun, 08 Feb 2015 17:55:10 +0100
> > Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006 at gmx.net> wrote:
> >
> >> On 07.02.2015 19:49, Stefan Tauner wrote:
> >>> Was implemented by SPARC newbies, does (cross-)compile but is not run-tested.
> >>>
> >>> Signed-off-by: Stefan Tauner <stefan.tauner at alumni.tuwien.ac.at>
> >> Thanks!
> >>
> >> Quoting wikipedia:
> >>> The endianness of the 32-bit SPARC V8 architecture is purely
> >>> big-endian. The 64-bit SPARC V9 architecture uses big-endian
> >>> instructions, but can access data in either big-endian or
> >>> little-endian byte order, chosen either at the application instruction
> >>> (load/store) level or at the memory page level (via an MMU setting).
> >>> The latter is often used for accessing data from inherently
> >>> little-endian devices, such as those on PCI buses.
> >> If that is true, we are totally screwed. How can we even begin to
> >> influence the instructions emitted by the compiler? And if the compiler
> >> emits bigendian instructions by default, can that be overridden via MMU
> >> setting? If yes, does Linux use the endianness manipulation via MMU for
> >> PCI devices, in which case we'd have to treat the architecture as
> >> littleendian from a flashrom POV?
> >>
> >> This is a nightmare.
> >>
> > Only if you make it one. :)
> > Maybe this allows you to sleep better:
> > https://gcc.gnu.org/ml/gcc-patches/2011-10/msg02240.html
> 
> Excellent, this means GCC won't try to screw us.
> 
> 
> > I am not sure if that "MMU settings" in wikipedia is referring to the
> > address space identifiers (ASIs), but it definitely screams [citation
> > needed]. 
> > In general the whole thing looks like a rather exotic if not esoteric
> > feature added to make porting Windows easier... in any case I am very
> > confident that it will not be encountered on real machines/OSes.
> 
> Yay!
> 
> 
> > So... the only question is if you agree and we commit this before
> > tagging 0.9.8-rc1 or not. I don't care too much about SPARC support,
> > but I *do* care about getting the release out. Please respond in a
> > timely manner.
> 
> With all this info and your excellent explanations on IRC, I want to say
> Thank You!
> Acked-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006 at gmx.net>

Let's hope I am correct. :)
Thanks, committed in r1882.

-- 
Kind regards/Mit freundlichen Grüßen, Stefan Tauner