> > Yes, but for all the chips produced up to now it is equal, and for later
> > chips we may decide based on the chip revision / manufacturer and if needed
> > apply a TSC per sec / CPU clocks per sec ratio for the respective chip to
> > get the correct CPU frequency.
>
> Well, in fact the TSC *is* supposed to *exactly* count CPU clock cycles,
> so I don't see what Martin means by "CPU clock speed need not be equal
> to TSC frequency".
>
> Please enlighten me :)
AFAIK the fact that TSC is the count of CPU cycles is not guaranteed
anywhere - there is no specifocation or databook or anything saying it. It
is guaranteed to advance forward at some constant speed, and not to give the
same the same value in 2^x years. That's all. No mention of CPU speed.
However, all current processors do maintain the 1:1 tsc speed versus CPU
clock speed ratio.
Vojtech
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