ACPI summary available

Nate Lawson nate at
Fri Jul 13 15:29:14 UTC 2007

Ian Smith wrote:
> On Thu, 12 Jul 2007, Nate Lawson wrote:
>  > Kevin Oberman wrote:
>  > > Thanks to a note on /., I found what looks to be a very nice summary of
>  > > ACPI and its myriad of states (C, D, G, S, and P). While it does not go
>  > > into ASL, the ACPI tables, or things of that sort, it is probably a
>  > > good starting place for those interested in just what ACPI is all about.
>  > > It filled in some gaps (especially about D and lower C states) for me.
>  > > 
>  > > One small request...I am far from an ACPI expert and there may be
>  > > serious flaws in the article that I am unaware of. If so, please let me
>  > > know so I don't recommend it more widely. IF it looks good, I plan to
>  > > post a message about it to mobile at .
>  > > 
>  > >
>  > 
>  > It's ok.  It doesn't include much real knowledge such as the fact that
>  > S2 has seldom been observed on a real system.  It includes very
>  > processor-rev specific stuff such as which P states are supported on
>  > which CPUs.  The diagram leaves out the embedded controller completely.
> One forgets how much one didn't know before one knew all about that :) 
> I found good background overview on lots of things I'd previously not
> had a clue about, especially the multi-core speed stepping and such,
> despite icky format and distracting ad bombardment ..
> Short of your shelf of books, deep specs and the code, can you suggest
> any other useful online ACPI in-a-nutshell references for neophytes?


Usenix paper


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