From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Brownell Subject: Re: Nested suspends; messages vs. states Date: Thu, 24 Mar 2005 08:38:37 -0800 Message-ID: <200503240838.37628.david-b@pacbell.net> References: <20050324095910.GD1354@elf.ucw.cz> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============48725291647244973==" In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces-qjLDD68F18O7TbgM5vRIOg@public.gmane.org Errors-To: linux-pm-bounces-qjLDD68F18O7TbgM5vRIOg@public.gmane.org To: linux-pm-qjLDD68F18O7TbgM5vRIOg@public.gmane.org Cc: Pavel Machek List-Id: linux-pm@vger.kernel.org --===============48725291647244973== Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline On Thursday 24 March 2005 7:48 am, Patrick Mochel wrote: > > On Thu, 24 Mar 2005, Pavel Machek wrote: > > > Seems to me that suspend-to-RAM and suspend-to-DISK make sense, and > > cover 90% of what people want to do. Add "standby" for "fast > > suspend-to-RAM" and you cover even ARM. I'd say that's good enuogh. > > We can treat STR and Standby nearly identically, exceptions being what we > do with the CPU, and what power states the devices enter. But, are there > any others? Quite possibly. Also look at the Montavista DPM stuff, where the operating points are a superset of those CPU states ... > What about this "big sleep" and "deep sleep" stuff? What platform were > those for? Is there documentation about them? The terms apply at least to OMAP, and there's plenty of documentation for those chips. Look at the OMAP 5912 docs: http://focus.ti.com/omap/docs/omapgenpage.tsp?navigationId=12341&templateId=5663&path=templatedata/cm/omapproc/data/omap5912 You'll have to register to get those (vs an NDA for an almost-identical version used inside cell phones -- yes, some Linux based ones too! -- which is one-big-PDF instead of lots of little one-per-chapter ones) and then the "Power Management" reference guide, SPRU753, talks about those details. Other platforms could use the same names differently of course. Capsule summary, "deep" means there's only a 32KHz clock, while "big" means the 48 MHz one is available to peripherals that need it (UARTs, USB, MMC/SD, camera, and so forth). Other ARM SOCs have similar distinctions; you might look at the Atmel AT91rm9200 for one that's a lot simpler (and where Linux support isn't quite as mature). - Dave --===============48725291647244973== Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline --===============48725291647244973==--