Re: [PATCH 3/9] x86/moorestown: add moorestown platform flags

[Pavel Machek <pavel@ucw.cz>]

On Fri 2009-06-26 09:54:54, Jesse Barnes wrote:
> On Fri, 26 Jun 2009 18:32:42 +0200 (CEST)
> Thomas Gleixner <tglx@linutronix.de> wrote:
> 
> > On Fri, 26 Jun 2009, Ingo Molnar wrote:
> > > [ Although it is beyond me why ABP was done - why wasnt HPET good
> > >   enough? HPET can do per CPU clockevents too and it's just as 
> > >   off-chip (and hence fundamentally slow) as ABP. ]
> > 
> > Welcome to the wonderful world of embedded systems. Just have a peek
> > into arch/[arm/powerpc/mips] to see what's coming up to us with full
> > force. I would not be surprised when we see an x86 system sharing the
> > device driver for i2c or whatever with an ARM SoC in the foreseable
> > future.
> 
> Ha, yeah I was just going to say "think embedded".  ABP is a much
> simpler spec and programming interface than HPET, and since we were
> designing new custom silicon, it made sense to just do the simple
> thing, rather than butchering an existing spec, then making a partial
> HPET that looks like ABP anyway and forcing any future HPET updates to
> conform to the new standard (very similar reasoning to the ACPI vs SFI
> discussion btw).  Hopefully the technologies we've come up with for

Very similary wrong, I'd say :-(. While you could have created
hpet-lite, where hpet-lite driver would work on hpet system, you went
and created something new.

And yes, SFI is similar disaster, you should just define subset of
acpi ('acpi-lite').

In the end, you are willing to use silicon for compatibility (arm
 instruction set needs less transistors, right?) and wasting millions
 of transistors, then try to save thousands with non-compatible
 devices :-(.
 
								Pavel
 


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