On   9 Aug, this message from Paul Mackerras echoed through cyberspace:

quoted

This fact was already catered for with the definition of outb/inb and
friends, which get an offset added to the port. Unfortunately, the
PowerMac IDE code undoes this and replaces it with a different
mechanism, which in essence removes the offset. Grrr..

Not any more.  I took that stuff out a few weeks ago so that the
CMD646 on the blue&white G3s could work.

Is that change in vger only? Submitted for 2.2.11?

Basically the problem is that the IDE driver assumes that you access
all IDE controllers via I/O ports.

Not a problem in itself, I guess: it's just that on the PPC, I/O ports
are not necessarily below 64k in processor-view..

When you have a controller that
has memory-mapped registers, there is a problem.  When you have a
system where one IDE controller has I/O ports and another has memory-
mapped registers, you have a bigger problem.  The current approach to
solving this problem is to map the addresses of the memory-mapped
registers into pseudo I/O port numbers (by subtracting _IO_BASE).  If
there is a better way, somebody let me know. :-)

I'd vote for making I/O ports a memory addresss like any other, and
making sure drivers get this address right. See my other post for
details..

Michel

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