Pallipadi, Venkatesh wrote: > Did C1, C2 work fine with 2.6.24? > Can you send me the full dmesg when it is failing to enter C1, C2 with > latest git + patch. > Output of > #grep . /sys/devices/system/cpu/cpu*/cpuidle/*/* > And also attach the acpidump output (pmtools package here > http://www.lesswatts.org/projects/acpi/utilities.php) No, C1/C2 did not seem to work with 2.6.24 - at least powertop reported 99,9% C0 usage. It was the same behavior as after applying the wakeup patch. However in 2.6.25 and 2.6.25-git11 C1/C2 worked correctly and C2 showed up in pt. But after applying your patch to 2.6.25-git11 they did not: git11: PowerTOP version 1.9 (C) 2007 Intel Corporation Cn Avg residency P-states (frequencies) C0 (cpu running) ( 9,4%) 1,80 Ghz 100,0% C1 0,0ms ( 0,0%) 1,60 Ghz 0,0% C2 0,4ms (90,6%) 800 Mhz 0,0% Wakeups-from-idle per second : 9051,0 interval: 5,0s git11 with wakeup-patch: PowerTOP version 1.9 (C) 2007 Intel Corporation Cn Avg residency P-states (frequencies) C0 (cpu running) (99,9%) 1,80 Ghz 100,0% C1 0,0ms ( 0,0%) 1,60 Ghz 0,0% C2 0,2ms ( 0,1%) 800 Mhz 0,0% Wakeups-from-idle per second : 59,8 interval: 10,0s In both cases the system was idle. I've uploaded the files you wanted: http://www-user.tu-chemnitz.de/~klada/misc/kernel/cpuidle_git11.txt http://www-user.tu-chemnitz.de/~klada/misc/kernel/cpuidle_git11_wakeuppatch.txt http://www-user.tu-chemnitz.de/~klada/misc/kernel/dmesg_git11.txt http://www-user.tu-chemnitz.de/~klada/misc/kernel/dmesg_git11_wakeuppatch.txt http://www-user.tu-chemnitz.de/~klada/misc/kernel/nx6125_acpidump.out If there is anything else I can do for debugging this issue please let me know. - Daniel