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    SubjectRe: [PATCH] (comments requested) adding finer-grained timing to PPC add_timer_randomness()
    Gabriel Paubert writes:

    > Reading the PVR is probably faster in this case, since you avoid a
    > potential cache miss.

    Yep.

    > As I said in an earlier message the __USE_RTC macro
    > should be made dependent on whether the kernel supports 601 or not.

    We don't have USE_RTC in 2.2. The proposed patch was for 2.2.19.

    > No, this is not what they are trying to capture. Furthermore the 7 LSB of
    > the decrementer on a 601 are not random (but they don't seem to be 0
    > always despite the documentation) so you would have to shift the result

    Don't you mean that the 7 LSB of RTCL aren't random and are supposed
    to be 0? The decrementer should decrement by 1 at a rate of 7.8125MHz
    and all the bits should be implemented.

    Paul.
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