Re: [PATCH][DOCUMENTATION BUGFIX] latency in micro-, not nanoseconds

[Ducrot Bruno <ducrot@poupinou.org>]

On Mon, Nov 10, 2003 at 04:32:09PM +0000, Dave Jones wrote:
> On Tue, Nov 04, 2003 at 05:08:16PM +0100, Dominik Brodowski wrote:
>  > All drivers [davej, can you please verify for powernow-k7?] set the 
>  > transition_latency time in microseconds, even though the core demanded
>  > nanoseconds. Instead of fixing up the drivers, fix up the core...
> 
> Hmm, I think you've unearthed a bug.
> 
> The 'latency' we read from the BIOS is in microseconds, but the hardware
> wants it in units of 10ns. We do the necessary maths, and everything is fine.
> But we're also storing that result in ..
> 
> 	policy->cpuinfo.transition_latency = latency;
> 
> Which is possibly not the right thing to be doing.
> I think we want to be storing the 'pre 10ns munging' value here correct?
> 

Well, maybe we have to double it as well (there is actually 2 steps, the
VID change and the FID change, each having 'latency' 1e(-8) second)...

something like:
	policy->cpuinfo.transition_latency = latency / 50;

perhaps?

-- 
Ducrot Bruno

--  Which is worse:  ignorance or apathy?
--  Don't know.  Don't care.