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    SubjectRe: New resources - pls, explain :-(
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    >>>>> "Paul" == Paul Mackerras <paulus@cs.anu.edu.au> writes:

    Paul> Linus Torvalds <torvalds@transmeta.com> wrote:
    >> readl() is for things that want to look like PCI (ie subsets of PCI
    >> like ISA and ISA PnP, or "look-alikes" of PCI like MCA).

    Paul> OK, that's indeed useful to know, thanks.

    Paul> In your opinion, should there be a guarantee that accesses
    Paul> initiated by readl/writel/etc. will not be reordered?

    Paul> Alternatively, should device driver writers be required to put
    Paul> in an explicit statement (mb() or something similar) when they
    Paul> use readl/writel/etc. and want to prevent the accesses being
    Paul> reordered?

    Now that you bring this up here it might be a good idea to mention
    that we (you and I both included) have just been discussing this in a
    different forum and there is disagreement between the Alpha and PPC
    camps on this one.

    My point is that the current implementation expects no protection
    against reordering and many current device drivers already deal with
    this correctly (I checked the aic7xxx this this morning and I noticed
    that it deals with this explicitly, even on the PPC).

    Jes

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