| From: "Rafael J. Wysocki" <rjw@xxxxxxx> | | On Wednesday, 21 March 2007 23:57, Pavel Machek wrote: | > Hi! | > | > > > Which is very much an indication of how weak ACPI is. It | > > > doesn't contemplate typical SOC behavior, which have a wide | > > > variety of system sleep states that leave the CPU on ... and | > > > which may not even *have* (or need!) a "cpu off" state. | > > > | > > > My own definition would be more like: the minimal RAM-based | > > > power-saving system state is "standby". If the system | > > > implements a deeper RAM-based system sleep state, that's "STR". | > > | > > Hmmm, this leaves the decision how to call each state COMPLETELY to the | > > implementor, doesn't it? | > | > Is that a problem? If someone is clever enough to implement suspend, I | > think we can trust them to name their states right. | > | > (And trust me, we can flame them if not). | > | > (Anyway, my definition would be "mem" == RAM is powered, everything | > else is down, except for devices needed for wakeup; "standby" == | > something is powered that can be powered down, we'll fix that in next version). | | I think we can define "standby" a bit more precisely. Something like: | - processes are frozen, | - devices are suspended, | - nonboot CPUs are down (and in low powered states, if possible), | - "system" devices may or may not be suspended, depending on the platform, | - the boot CPU may or may not be in a low power state, depending on the platform, | - RAM is powered | - wake up need not be BIOS-driven (main difference from "mem") --- I would be tempted to say that that last bullet is the distinguishing characteristic - that you come back from standby by just continuing where you left off, but you come back from StR by something akin to booting. scott -- scott preece motorola mobile devices, il67, 1800 s. oak st., champaign, il 61820 e-mail: preece@xxxxxxxxxxxx fax: +1-217-384-8550 phone: +1-217-384-8589 cell: +1-217-433-6114 pager: 2174336114@xxxxxxxxx _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
