[U-Boot-Users] MPC8245 Silicon Workaround

[Marc Leeman]

What should be the policy on the tweaking hardware settings in the
u-boot bootloader? [safe or not].

As a result of the PCI/Memory buffer remarks, I re-did my tests and I
the troubles which required me to disable 3 of the 4 hardware buffers
with the register PCMBCR are no longer there (data corruption).

However, since then, my development board died on me and I had to
replace it with a new production board which has a later (>1.2) silicon
revision of the MPC8245 processor.

Disabling the buffers is safe: it provides a workaround for a possible
silicon bug in certain MPC8245 processors. However, it comes at a small
(<< 1%) performance cost IIRC [1].

If it should be _safe_; then the patch I sent and is now in CVS should
stay; if not, it can be commented out. I think it is still good to leave
it in comments though...

Any thoughts?

  Marc.

[1] Obviously, I need to re-do these performance tests on a board with
does not have the silicon bug (later revision, I am currently trying
to trace the exact revision number in our ordering system).

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