On 04/02/13 15:15, Jacob Pan wrote: > RAPL(Running Average Power Limit) interface provides platform software > with the ability to monitor, control, and get notifications on SOC > power consumptions. Since its first appearance on Sandy Bridge, more > features have being added to extend its usage. In RAPL, platforms are > divided into domains for fine grained control. These domains include > package, DRAM controller, CPU core (Power Plane 0), graphics uncore > (power plane 1), etc. > > The purpose of this driver is to expose RAPL for userspace > consumption. Overall, RAPL fits in the generic thermal layer in > that platform level power capping and monitoring are mainly used for > thermal management and thermal layer provides the abstracted interface > needed to have portable applications. > > Specifically, userspace is presented with per domain cooling device > with sysfs links to its kobject. Although RAPL domain provides many > parameters for fine tuning, long term power limit is exposed as the > single knob via cooling device state. Whereas the rest of the > parameters are still accessible via the linked kobject. This simplifies > the interface for both simple and advanced use cases. > > Eventfd is used to provide notifications to the userspace. At per domain > level, use can choose any event capable parameters to register for > threshold crossing notifications. This is shamelessly "borrowed" from > cgroup with some trimming/fitting. > > Zhang, Rui's initial RAPL driver was used as a reference and starting > point. Many thanks. > https://lkml.org/lkml/2011/5/26/93 > > Unlike the patch above, which is mainly for monitoring, this driver > focus on the control and usability by user applications. > > Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> > --- > drivers/platform/x86/Kconfig | 8 + > drivers/platform/x86/Makefile | 1 + > drivers/platform/x86/intel_rapl.c | 1323 +++++++++++++++++++++++++++++++++++++ > drivers/platform/x86/intel_rapl.h | 249 +++++++ > 4 files changed, 1581 insertions(+) > create mode 100644 drivers/platform/x86/intel_rapl.c > create mode 100644 drivers/platform/x86/intel_rapl.h > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > index 3338437..34bcd52 100644 > --- a/drivers/platform/x86/Kconfig > +++ b/drivers/platform/x86/Kconfig > @@ -781,4 +781,12 @@ config APPLE_GMUX > graphics as well as the backlight. Currently only backlight > control is supported by the driver. > > +config INTEL_RAPL > + tristate "Intel RAPL Support" > + depends on X86 && THERMAL > + default y > + ---help--- > + RAPL, AKA, Running Average Power Limit provides mechanisms to enforce RAPL, aka Running Average Power Limit, provides mechanisms to enforce or a.k.a., but not AKA or even: RAPL (Running Average Power Limit) provides mechanisms to enforce > + and monitor per domain power consumption limits of supported Intel CPUs. > + > endif # X86_PLATFORM_DEVICES -- ~Randy -- To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
