ACPI summary available

Ian Smith smithi at
Fri Jul 13 13:21:24 UTC 2007

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?

Cheers, Ian

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