Re: Cyrix patch : Proposal?

Mike Jagdis (mike@roan.co.uk)
Mon, 10 Nov 1997 11:04:57 +0000 (GMT/BST)


On Sat, 8 Nov 1997, Willem Riede <wriede@monmouth.com> wrote:

> I think it would be a feather in Linux's cap if it automatically recognized
> what CPU it runs on and sets any parameters that make that CPU function most
> effectively (and some may have to be set at config for recompile time).

That was my intention with the original non-Intel (nee Cyrix)
patch. Once you've recognised the chip the feature setting is
a relatively trivial amount of code so you might as well do
it there. Moving it to user space would mean you take thousands
of cycles longer :-). The reason it's all done with config
options is for testing. There is probably no reason to ask
such questions at this stage.

The reason ARR, linear burst mode etc. aren't handled by
the patch is because we can't predict what the "best" settings
are without additional knowledge that it isn't possible to
probe. We have to assume that the BIOS has set things reasonably.
These are things that _could_ be done in user space - but only
by people who know their system and what they are doing.

Mike

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