SS20 and SMP using Ross modules
I have here an SS20 which has run Woody reliably for an extended period. It has
2x Ross 625 CPUs, PROM 2.25R and 256Mb RAM.
It runs single-processor 2.4.27 from Sarge reliably, but attempting to boot SMP
gives an interrupt 15/watchdog error.
If it is given this sequence of commands:
it will boot into SMP, but eventually fails with a "wrong magic" error.
If the Ross modules are replaced by Suns then it will boot either single
processor or SMP successfully, and run reliably.
Reverting to Ross modules, if I build a standalone kernel I find it's too large
to boot from disc, but I can boot it over the LAN (boot net root=/dev/sda2) and
the system runs SMP reliably. However I notice that while the BogoMIPS rating of
a single CPU is 150 when running SMP it's dropped to 104 per processor- I
thought this was calibrated using a tight loop?
I'm assuming that none of the core developers will be looking at this because of
the age of the hardware, and I don't have the hardware information to even start
making sense of this sort of problem. However as a workaround can anybody point
me at the documentation that describes the Debian/SPARC-specific kernel rebuild
procedure- running the standard "make vmlinux" gives me a kernel image of around
My position is that I'm keen on promoting Sun kit for in-house use, but having
to boot over the LAN makes it difficult to argue that they are a viable
alternative to PCs, and if I'm not confident making that argument I'm not going
to put my neck on the block and ask for money for newer systems.
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk
[Opinions above are the author's, not those of his employers or colleagues]