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    SubjectRe: [PATCHv2 1/3] ARM: Translate delay.S into (mostly) C
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    On Thu, 2010-10-28 at 14:19 -0700, Stephen Boyd wrote:
    > We want to allow machines to override the __delay() implementation
    > at runtime so they can use a timer based __delay() routine. It's
    > easier to do this using C, so let's write udelay and friends in C.
    >
    > We lose the #if 0 code, which according to Russell is used "to
    > make the delay loop more stable and predictable on older CPUs"
    > (see http://article.gmane.org/gmane.linux.kernel/888867 for more
    > info). We shouldn't be too worried though, since we'll soon add
    > functionality allowing a machine to set the __delay() loop
    > themselves, thus allowing machines to resurrect the commented out
    > code should they need it.
    >
    > Nico expressed concern that fixed lpj cmdlines will break due to
    > compiler optimizations. That doesn't seem to be the case since
    > before and after this patch I get the same lpj value when running
    > my CPU at 19.2 MHz. That should be sufficiently slow enough to
    > cover any machine running Linux.

    Nico, are you ready to sign off on this?

    Daniel

    --

    Sent by a consultant of the Qualcomm Innovation Center, Inc.
    The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.



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