Re: Current state of the Linux kernel on SPARC

On Fri, 2025-08-29 at 18:41 -0400, Dennis Clarke wrote:
> I will hunt around and see what I have laying about in a back room.
> I know I have old Netra X1 stuff and maybe a few other units with very
> old UltraSPARC processors in them. They will be horrifically slow.
> The SPARC M7 or M8 will be a unicorn. Heard of only in myth.

While I don't assume you have a SPARC M7-compatible machine, I think
chances are good you might have a T1 machine. As a bonus, a test on
an UltraSPARC I or II is very welcome as well.

To clarify this:

The kernel code in question contains optimizations for different CPUs,
namely:

- UltraSPARC I
- UltraSPARC III
- Niagara 1
- Niagara 2
- Niagara 4
- SPARC M7

All but Niagara 2 had bugs which Michael Karcher fixed.

So far, I successfully tested on UltraSPARC III and Niagara 4 as I have
access to these machines. I also own a Niagara 2 machine, but there is
no testing necessary as the code was not touched.

I also tested on QEMU which emulates an UltraSPARC II, meaning that the
UltraSPARC I code was tested (there is no UltraSPARC II code). I used a
patched kernel to force Niagara 4 to use the Niagara 1 code which worked
without problems.

Still, it would be nice to have testing on real machines of these types:

- UltraSPARC I or II
- Niagara 1
- SPARC M7

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913