Re: iomapping a big endian area

From: Benjamin Herrenschmidt (benh_at_kernel.crashing.org)
Date: 04/04/05

  • Next message: Tejun Heo: "Re: sata_sil Mod15Write quirk workaround patch for vanilla kernel avaialble." 
    To: James Bottomley <James.Bottomley@SteelEye.com>
Date:	Mon, 04 Apr 2005 17:50:39 +1000

    On Sat, 2005-04-02 at 22:27 -0600, James Bottomley wrote:
    > On Sat, 2005-04-02 at 20:08 -0800, David S. Miller wrote:
    > > > Did anyone have a preference for the API? I was thinking
    > > > ioread32_native, but ioread32be is fine too.
    > >
    > > I think doing foo{be,le}{8,16,32}() would be consistent with
    > > our byteorder.h interface names.
    >
    > Thinking about this some more, I know of no case of a BE bus connected
    > to a LE system, nor do I think anyone would ever create such a beast, so
    > our only missing interface is for a BE bus on a BE system.

    It's more a matter of the device than the bus imho...

    > Thus, I think io{read,write}{16,32}_native are better interfaces ...

    I disagree. The driver will never "know" ...

    > they basically mean pass memory operations without byte swaps, so
    > they're well defined on both BE and LE systems and correspond exactly to
    > our existing _raw_{read,write}{w,l} calls (principle of least surprise).

    I don't think it's sane. You know that your device is BE or LE and use
    the appropriate interface. "native" doesn't make sense to me in this
    context.

    Ben.

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  • Next message: Tejun Heo: "Re: sata_sil Mod15Write quirk workaround patch for vanilla kernel avaialble."

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