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    SubjectRe: Big Fix for 2.2.1

    On Wed, 27 Jan 1999, Andy Poling wrote:
    >
    > On Wed, 27 Jan 1999, Linux Lists wrote:
    > > Please don't do that. The Cyclades driver supports both ISA and PCI cards,
    > > and it follows correctly the current definition, by ioremap'ing addresses
    > > above 1MB and using readX/writeX for _all_ accesses to MMIO resources (in
    > > ISA or PCI). Doing this change would mean having to test which card I'm
    > > accessing _every time_ I do a readX/writeX, which is completelly
    > > unacceptable (for obvious performance reasons).
    >
    > Perhaps I'm naive, or missing something really obvious here, but...
    >
    > Shouldn't you already know which bus-type of card you're accessing long
    > before you get to the performance-critical code in any driver?

    The issue here is that I thought Linus mentioned a change in the ioremap
    function, which would require ISA cards to be accessed by
    read_ISA_X/write_ISA_X and others by readX/writeX. Since my driver uses
    readX/writeX to access _both_ (PCI and ISA), that would mean having to add
    the following for every call to this functions:

    if (ISA)
    read_ISA_X/write_ISA_X;
    else
    readX/writeX;


    Interestingly enough, Linus _didn't_ mention anything about changing the
    ioremap function (and I have no idea where I got this idea from). Thus, my
    e-mail is completely unfounded and can be ignored.

    Sorry for the unnecessary noise.

    Regards and Apologies,
    Ivan


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