1*5229e87dSLen BrownWhat: /sys/firmware/acpi/interrupts/ 2*5229e87dSLen BrownDate: February 2008 3*5229e87dSLen BrownContact: Len Brown <lenb@kernel.org> 4*5229e87dSLen BrownDescription: 5*5229e87dSLen Brown All ACPI interrupts are handled via a single IRQ, 6*5229e87dSLen Brown the System Control Interrupt (SCI), which appears 7*5229e87dSLen Brown as "acpi" in /proc/interrupts. 8*5229e87dSLen Brown 9*5229e87dSLen Brown However, one of the main functions of ACPI is to make 10*5229e87dSLen Brown the platform understand random hardware without 11*5229e87dSLen Brown special driver support. So while the SCI handles a few 12*5229e87dSLen Brown well known (fixed feature) interrupts sources, such 13*5229e87dSLen Brown as the power button, it can also handle a variable 14*5229e87dSLen Brown number of a "General Purpose Events" (GPE). 15*5229e87dSLen Brown 16*5229e87dSLen Brown A GPE vectors to a specified handler in AML, which 17*5229e87dSLen Brown can do a anything the BIOS writer wants from 18*5229e87dSLen Brown OS context. GPE 0x12, for example, would vector 19*5229e87dSLen Brown to a level or edge handler called _L12 or _E12. 20*5229e87dSLen Brown The handler may do its business and return. 21*5229e87dSLen Brown Or the handler may send send a Notify event 22*5229e87dSLen Brown to a Linux device driver registered on an ACPI device, 23*5229e87dSLen Brown such as a battery, or a processor. 24*5229e87dSLen Brown 25*5229e87dSLen Brown To figure out where all the SCI's are coming from, 26*5229e87dSLen Brown /sys/firmware/acpi/interrupts contains a file listing 27*5229e87dSLen Brown every possible source, and the count of how many 28*5229e87dSLen Brown times it has triggered. 29*5229e87dSLen Brown 30*5229e87dSLen Brown $ cd /sys/firmware/acpi/interrupts 31*5229e87dSLen Brown $ grep . * 32*5229e87dSLen Brown error:0 33*5229e87dSLen Brown ff_gbl_lock:0 34*5229e87dSLen Brown ff_pmtimer:0 35*5229e87dSLen Brown ff_pwr_btn:0 36*5229e87dSLen Brown ff_rt_clk:0 37*5229e87dSLen Brown ff_slp_btn:0 38*5229e87dSLen Brown gpe00:0 39*5229e87dSLen Brown gpe01:0 40*5229e87dSLen Brown gpe02:0 41*5229e87dSLen Brown gpe03:0 42*5229e87dSLen Brown gpe04:0 43*5229e87dSLen Brown gpe05:0 44*5229e87dSLen Brown gpe06:0 45*5229e87dSLen Brown gpe07:0 46*5229e87dSLen Brown gpe08:0 47*5229e87dSLen Brown gpe09:174 48*5229e87dSLen Brown gpe0A:0 49*5229e87dSLen Brown gpe0B:0 50*5229e87dSLen Brown gpe0C:0 51*5229e87dSLen Brown gpe0D:0 52*5229e87dSLen Brown gpe0E:0 53*5229e87dSLen Brown gpe0F:0 54*5229e87dSLen Brown gpe10:0 55*5229e87dSLen Brown gpe11:60 56*5229e87dSLen Brown gpe12:0 57*5229e87dSLen Brown gpe13:0 58*5229e87dSLen Brown gpe14:0 59*5229e87dSLen Brown gpe15:0 60*5229e87dSLen Brown gpe16:0 61*5229e87dSLen Brown gpe17:0 62*5229e87dSLen Brown gpe18:0 63*5229e87dSLen Brown gpe19:7 64*5229e87dSLen Brown gpe1A:0 65*5229e87dSLen Brown gpe1B:0 66*5229e87dSLen Brown gpe1C:0 67*5229e87dSLen Brown gpe1D:0 68*5229e87dSLen Brown gpe1E:0 69*5229e87dSLen Brown gpe1F:0 70*5229e87dSLen Brown gpe_all:241 71*5229e87dSLen Brown sci:241 72*5229e87dSLen Brown 73*5229e87dSLen Brown sci - The total number of times the ACPI SCI 74*5229e87dSLen Brown has claimed an interrupt. 75*5229e87dSLen Brown 76*5229e87dSLen Brown gpe_all - count of SCI caused by GPEs. 77*5229e87dSLen Brown 78*5229e87dSLen Brown gpeXX - count for individual GPE source 79*5229e87dSLen Brown 80*5229e87dSLen Brown ff_gbl_lock - Global Lock 81*5229e87dSLen Brown 82*5229e87dSLen Brown ff_pmtimer - PM Timer 83*5229e87dSLen Brown 84*5229e87dSLen Brown ff_pwr_btn - Power Button 85*5229e87dSLen Brown 86*5229e87dSLen Brown ff_rt_clk - Real Time Clock 87*5229e87dSLen Brown 88*5229e87dSLen Brown ff_slp_btn - Sleep Button 89*5229e87dSLen Brown 90*5229e87dSLen Brown error - an interrupt that can't be accounted for above. 91*5229e87dSLen Brown 92*5229e87dSLen Brown Root has permission to clear any of these counters. Eg. 93*5229e87dSLen Brown # echo 0 > gpe11 94*5229e87dSLen Brown 95*5229e87dSLen Brown All counters can be cleared by clearing the total "sci": 96*5229e87dSLen Brown # echo 0 > sci 97*5229e87dSLen Brown 98*5229e87dSLen Brown None of these counters has an effect on the function 99*5229e87dSLen Brown of the system, they are simply statistics. 100