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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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