Hello, On Thu, Nov 3, 2011 at 7:21 AM, Lin Ming <ming.m.lin@xxxxxxxxx> wrote: >> * How much does this add on top of hardware timed auto spindown and >> dynamic link power management? > > Sorry, I don't understand this question. > What do you mean? I was curious about the amount of additional power saving on top of the existing PM features. >> * Do the added benefits justify yet another runtime powersaving >> mechanism? > > There will be ACPI firmware which supports ata port runtime D3Cold. > To enable ata port runtime PM is the first step. libata can already turn off unused ports although it wouldn't go as far as putting the whole controller into D3. >> * Any way we can tie the other stuff with overall runtime PM? > > What's the other stuff? > Do you mean tie disk/link/port/controller stuff with overall runtime PM? Hardware initiated spin-down (hdparm -S) and link power saving (look for ata_lpm_*). It would be great if there's an overall design how they interact before adding yet another PM vector. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
