[U-Boot] [RFC PATCH v1] mips: add atomic operations

[Chris Packham]

On Fri, 7 Sep 2018, 10:24 PM Stefan, <sr at denx.de> wrote:

> Hi Chris,
>
> (added Daniel)
>
> On 07.09.2018 10:24, Chris Packham wrote:
> > Add mips version of atomic.h and basic atomic operations. These aren't
> > the optimised versions from the Linux kernel, just basic stubs that
> > satisfy users that need something to define atomic_inc() etc.
> >
> > Signed-off-by: Chris Packham <judge.packham at gmail.com>
> >
> > ---
> > At $dayjob we have a mips target that we want to run UBIFS on. UBIFS
> > requires atomic.h. This is my naive attempt to supply enough of atomic.h
> > to satisfy UBIFS.
> >
> > It's no coincidence that this looks like the arm version. I am
> > wondering if it's worth a asm-generic version leaving architectures that
> > actually need true atomic operations able to define them.
>
> I did a pretty similar job and copied the files from xtensa a few
> weeks ago:
>
> https://patchwork.ozlabs.org/patch/958286/


Weird coincidence. I figured noone had needed ubifs on mips since the need
for atomic.h has been there for a while.

I'm more than happy for your version to go in since it's part of a bigger
series. The only thing missing is 64 bit support (our platform happens to
be mips64) but i don't think ubifs cares.


> It would be better of course, to have some generic version of this
> file. But frankly, I don't have the time right now for this.
>

Given that the arm, xtensa and now mips are so similar it's probably worth
it. I'll see if i can find some cycles to spend on it.