15229e87dSLen BrownWhat: /sys/firmware/acpi/interrupts/ 25229e87dSLen BrownDate: February 2008 35229e87dSLen BrownContact: Len Brown <lenb@kernel.org> 45229e87dSLen BrownDescription: 55229e87dSLen Brown All ACPI interrupts are handled via a single IRQ, 65229e87dSLen Brown the System Control Interrupt (SCI), which appears 75229e87dSLen Brown as "acpi" in /proc/interrupts. 85229e87dSLen Brown 95229e87dSLen Brown However, one of the main functions of ACPI is to make 105229e87dSLen Brown the platform understand random hardware without 115229e87dSLen Brown special driver support. So while the SCI handles a few 125229e87dSLen Brown well known (fixed feature) interrupts sources, such 135229e87dSLen Brown as the power button, it can also handle a variable 145229e87dSLen Brown number of a "General Purpose Events" (GPE). 155229e87dSLen Brown 165229e87dSLen Brown A GPE vectors to a specified handler in AML, which 175229e87dSLen Brown can do a anything the BIOS writer wants from 185229e87dSLen Brown OS context. GPE 0x12, for example, would vector 195229e87dSLen Brown to a level or edge handler called _L12 or _E12. 205229e87dSLen Brown The handler may do its business and return. 215229e87dSLen Brown Or the handler may send send a Notify event 225229e87dSLen Brown to a Linux device driver registered on an ACPI device, 235229e87dSLen Brown such as a battery, or a processor. 245229e87dSLen Brown 255229e87dSLen Brown To figure out where all the SCI's are coming from, 265229e87dSLen Brown /sys/firmware/acpi/interrupts contains a file listing 275229e87dSLen Brown every possible source, and the count of how many 285229e87dSLen Brown times it has triggered. 295229e87dSLen Brown 305229e87dSLen Brown $ cd /sys/firmware/acpi/interrupts 315229e87dSLen Brown $ grep . * 325229e87dSLen Brown error:0 335229e87dSLen Brown ff_gbl_lock:0 345229e87dSLen Brown ff_pmtimer:0 355229e87dSLen Brown ff_pwr_btn:0 365229e87dSLen Brown ff_rt_clk:0 375229e87dSLen Brown ff_slp_btn:0 385229e87dSLen Brown gpe00:0 395229e87dSLen Brown gpe01:0 405229e87dSLen Brown gpe02:0 415229e87dSLen Brown gpe03:0 425229e87dSLen Brown gpe04:0 435229e87dSLen Brown gpe05:0 445229e87dSLen Brown gpe06:0 455229e87dSLen Brown gpe07:0 465229e87dSLen Brown gpe08:0 475229e87dSLen Brown gpe09:174 485229e87dSLen Brown gpe0A:0 495229e87dSLen Brown gpe0B:0 505229e87dSLen Brown gpe0C:0 515229e87dSLen Brown gpe0D:0 525229e87dSLen Brown gpe0E:0 535229e87dSLen Brown gpe0F:0 545229e87dSLen Brown gpe10:0 555229e87dSLen Brown gpe11:60 565229e87dSLen Brown gpe12:0 575229e87dSLen Brown gpe13:0 585229e87dSLen Brown gpe14:0 595229e87dSLen Brown gpe15:0 605229e87dSLen Brown gpe16:0 615229e87dSLen Brown gpe17:0 625229e87dSLen Brown gpe18:0 635229e87dSLen Brown gpe19:7 645229e87dSLen Brown gpe1A:0 655229e87dSLen Brown gpe1B:0 665229e87dSLen Brown gpe1C:0 675229e87dSLen Brown gpe1D:0 685229e87dSLen Brown gpe1E:0 695229e87dSLen Brown gpe1F:0 705229e87dSLen Brown gpe_all:241 715229e87dSLen Brown sci:241 725229e87dSLen Brown 735229e87dSLen Brown sci - The total number of times the ACPI SCI 745229e87dSLen Brown has claimed an interrupt. 755229e87dSLen Brown 765229e87dSLen Brown gpe_all - count of SCI caused by GPEs. 775229e87dSLen Brown 785229e87dSLen Brown gpeXX - count for individual GPE source 795229e87dSLen Brown 805229e87dSLen Brown ff_gbl_lock - Global Lock 815229e87dSLen Brown 825229e87dSLen Brown ff_pmtimer - PM Timer 835229e87dSLen Brown 845229e87dSLen Brown ff_pwr_btn - Power Button 855229e87dSLen Brown 865229e87dSLen Brown ff_rt_clk - Real Time Clock 875229e87dSLen Brown 885229e87dSLen Brown ff_slp_btn - Sleep Button 895229e87dSLen Brown 905229e87dSLen Brown error - an interrupt that can't be accounted for above. 915229e87dSLen Brown 925229e87dSLen Brown Root has permission to clear any of these counters. Eg. 935229e87dSLen Brown # echo 0 > gpe11 945229e87dSLen Brown 955229e87dSLen Brown All counters can be cleared by clearing the total "sci": 965229e87dSLen Brown # echo 0 > sci 975229e87dSLen Brown 985229e87dSLen Brown None of these counters has an effect on the function 995229e87dSLen Brown of the system, they are simply statistics. 100