I-Cache incoherence

[Marcel Moolenaar]

On May 27, 2008, at 7:48 AM, Marc Lörner wrote:

> Hi,
> when testing snapshot 7.0-Stable from 05/2008 and
> 8.0-Current installation discs, it seems that the image
> gets loaded from disc into data cache.
>
> When we now try to access this just loaded data as instructions
> => I-Cache is not coherent and HW just hangs
> (after output: "Trying to mount root from /dev/md0"
> and before choosing the terminal-emulation)

I thought I used a big enough hammer to make this work...

The only place we don't make the I-cache coherent is for the
ptrace interface. This typically shows up as not hitting a
breakpoint after setting it. In all other cases we seem to be
fine.

> I tried to verify this assumption with inserting a"ptc.l"-instruction
> before every itc.i in Instruction_TLB, so we force the HW to ensure
> coherency.
> =>It now runs further to sysinstall.

I'm confused. Are we talking about the translation cache or
the data/instruction cache?

-- 
Marcel Moolenaar
xcllnt at mac.com