That makes sense. Adopting ACPI interfaces in the future would be the right way to go. Thanks for the clarification.
-- jdh Liu, Jiang wrote: > Hi Julia, > Thanks for your reminder about rules to access throttling > registers. > CPU idle notificatication should be a long lived component > because it's a pure software interface and could also be used by > components other than FIPE. > For FIPE driver itself, it will only be used to support Intel > 5000/7300 chipsets and won't be used on later Intel chipsets/CPUs. > For future memory power management, I think it would be better to > adopt ACPI interfaces other than directly talking to hardware. > > Regards > --Gerry > > Julia.Harper at Sun.COM <mailto:Julia.Harper at Sun.COM> wrote: >> Gerry -- >> >> I see the FIPE driver directly modifies the throttling >> registers in the memory controller. >> >> Although there is no issue in doing this in Intel systems >> with a 7300 or 5000 series Memory Controller Hub, I want >> bring up that OS configuring and enabling throttling >> registers in later (Nehalem-based) Intel systems should be >> avoided. System designers assume that BIOS and/or the >> service processor have ownership of throttling behavior. >> Throttling may be used for managing system issues the OS is >> not aware of. If the OS and the layer beneath the OS both >> attempt to use throttling for different purposes, this could >> cause a problem. >> >> Do you see the cpu idle notification / FIPE driver solution >> as a long lived approach to memory power management? >> >> -- jdh >> >> >> Liu, Jiang wrote: >>> Hi buddies, >>> I have developed a device driver for Intel 5000/7300 chipset >>> which puts memory into power saving state when system is idle. >>> Could you please help to review it? Webrev is at >>> http://cr.opensolaris.org/~gerry/fipe_20090408/. >>> There are two main parts in the webrev. The first one is >>> enhancement to dcopy/ioat driver to support FIPE. The second one is >>> FIPE driver it self. Thanks! >>> Liu Jiang (Gerry) >>> Senior Software Engineer >>> OpenSolaris, OTC, SSG, Intel >>> Tel: (8610)82171643 >>> iNet: 8-758-1643 >>> Location: Raycom 9W013 >>> _______________________________________________ >>> tesla-dev mailing list >>> tesla-dev at opensolaris.org >>> http://mail.opensolaris.org/mailman/listinfo/tesla-dev > > Liu Jiang (Gerry) > OpenSolaris, OTC, SSG, Intel -- --------------------- Julia Harper, julia.harper at sun.com
