From: Wolfgang Denk <wd@de...> - 2002-01-25 01:06:53
in message <16929.020124@...> you wrote:
> Interestingly enough, my custom 8260 board has the same problem when I
> try to enable DCACHE in PPCBoot. Never worried too much about that,
This is absolutley NOT surprising. It cannot work.
> because when Linux boots it enables the data cache and everything
> works fine :-)
On MPC8xx and MPC8260 systems (which have a CPM and IMMR and all this
stuff) you have to make sure that accesses to the IMMR are not
cached. Otherwise things like the polling serial drivers cannot work.
Since we don;t use the MMU on these systems, there is no way to
exclude just the IMMR from being cached, so the data cache must be
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