David Gibson wrote:

The 405gp manual implies that an mtspr to the PIT writes both the
decrementing value and the reload register.  Is this a hardware /
documentation bug?

Well, the point is that it writes the reload register.  When it
gets to zero, it reloads with this register, which is wrong.

.....  Could the PIT be used this way if auto-reload was
disabled?

No, because the PIT doesn't count down past zero.  If they would
have allowed this, we could have disabled the auto-reload and
treated it just like the decrementer.

The best I could come up with is just allow the PIT run with a
proper and fixed reload value.  It isn't a decrementer and we
can't treat it like one.

Sure, but it's still useful to be able to run binaries copied from
"normal" PPC machines.

Just remember that you can't be mixing float emulation and in-line
floating point software.


	-- Dan

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