Re: OPTION_MEMORY_MAPPED is broken

David Mosberger-Tang (davidm@AZStarNet.com)
Sun, 31 Dec 1995 10:27:55 -0700


>>>>> On Mon, 25 Dec 1995 12:20:52 +0100 (MET), Thomas Bogendoerfer <tsbogend@bigbug.franken.de> said:

Thomas> Because I get some problems with I/O access to the NCR (bad
Thomas> data parity), I'm wondering if there is a way to use _only_
Thomas> memory accesses ? Even with OPTION_MEMORY_MAPPED there are
Thomas> some inb()s.

As far as I know, parity generation is done by the same circuitry,
independent of whether a PCI memory or PCI I/O access is being
performed. Thus, I don't think changing from I/O to memory space will
make much difference w.r.t. bad parity problems.

Have you tried 1.3.52 or some such? The latest ncr driver has the
mb() instructions in the read/write macros, so it's more likely to
work, though I haven't tried it myself.

--david