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    SubjectRe: [linux-kernel] Re: [PATCH] x86: provide a DMI based port 0x80 I/O delay override.
    H. Peter Anvin wrote:
    > And shoot the designer of this particular microcontroller firmware.
    Well, some days I want to shoot the "designer" of the entire Wintel
    architecture... it's not exactly "designed" by anybody of course, and
    today it's created largely by a collection of Taiwanese and Chinese ODM
    firms, coupled with Microsoft WinHEC and Intel folks. At least they
    follow the rules and their ACPI and BIOS code say that they are using
    port 80 very clearly if you use PnP and ACPI properly. And in the old
    days, you were "supposed" to use the system BIOS to talk to things like
    the PIT that had timing issues, not write your own code.

    Or perhaps the ACPI spec should specify a timing loop spec and precisely
    specify the desired timing after accessing an I/O port till that device
    has properly "acted" on that operation.

    The idea that Port 80 was "unused" and appropriate for delay purposes
    elicited skepticism by Linus that is recorded for posterity in the
    comments of the relevant Linux include files - especially since it was
    clearly "used" for non-delay purposes, by cards that could be plugged
    into a PCI (fast), not just an 8-bit ISA, bus.

    Perhaps we should declare the world of ACPI systems a separate "arch"
    from the world of l'ancien regime where folklore about which ports were
    used for what ruled. I lived through those old days, and they were not
    wonderful, either.

    The world sucks, and Linux is supposed to be able to adapt to that
    world, suckitude and all.

     \ /
      Last update: 2008-01-08 02:41    [W:0.023 / U:7.012 seconds]
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