This is to reopen very old thread 700865 because I am having the same annoying issue on Dell Latitude D830 with Karmic kernel 2.6.31-20-generic.
If I disconnect AC for more then 16 seconds I need to stay disconnected to get full speed. Otherwise I get stuck to 800MHz. If I reconnect before 16 seconds full speed is kept.
All states/governors/frequencies work ok unless I preform the described procedure. If I disable ACPI from grub params or bios it obviously does not happen. Suspend to disk/mem both work ok. I never noticed such an slow down on Windows before purging it. I recompiled kernel, changed acpi_cpufreq to module to reload it and replaced DSDT to no avail. Needless to say that standard
/sys/devices/system/cpu?/* control files are present but useless to change cur_freq when locked down. This happens no matter what governor I have selected. I also upgraded from A12 to A15 bios.
This is how to reproduce it :
- Boot on batery
- Wait 16 seconds
- Connect AC power
OR
- Boot on AC power
- Remove AC Power
- Wait 16 seconds
- Reconnect AC Power
Acpi events reflect just described procedure :
Code:
samuel@d830:~$ acpi_listen
#AC unplugged
ac_adapter AC 00000080 00000000
battery BAT0 00000080 00000001
#AC plugged in
ac_adapter AC 00000080 00000001
#following events get me stuck to 800MHz
processor CPU0 00000080 00000004
processor CPU1 00000080 00000004
battery BAT0 00000080 00000001
battery BAT0 00000080 00000001
#AC unplugged
ac_adapter AC 00000080 00000000
battery BAT0 00000080 00000001
#16 seconds later (full speed recovered here but I am on BAT! argh!)
processor CPU0 00000080 00000000
processor CPU1 00000080 00000000
This is my CPU info :
Code:
samuel@d830:~$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel(R) Core(TM)2 Duo CPU T7250 @ 2.00GHz
stepping : 13
cpu MHz : 2000.000
cache size : 2048 KB
physical id : 0
siblings : 2
core id : 0
cpu cores : 2
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm tpr_shadow vnmi flexpriority
bogomips : 3989.21
clflush size : 64
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel(R) Core(TM)2 Duo CPU T7250 @ 2.00GHz
stepping : 13
cpu MHz : 2000.000
cache size : 2048 KB
physical id : 0
siblings : 2
core id : 1
cpu cores : 2
apicid : 1
initial apicid : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm lahf_lm tpr_shadow vnmi flexpriority
bogomips : 3989.97
clflush size : 64
power management:
I also get an strange kernel log when AC is plugged in
Code:
Mar 24 19:53:32 d830 kernel: [ 870.421651] atkbd.c: Unknown key pressed (translated set 2, code 0x8d on isa0060/serio0).
Mar 24 19:53:32 d830 kernel: [ 870.421657] atkbd.c: Use 'setkeycodes e00d <keycode>' to make it known.
This is what I get when locked to 800Mhz
Code:
root@d830:~# cpufreq-info
cpufrequtils 005: cpufreq-info (C) Dominik Brodowski 2004-2006
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time: 0
hardware limits: 800 MHz - 2.00 GHz
available frequency steps: 2.00 GHz, 1.60 GHz, 1.20 GHz, 800 MHz
available cpufreq governors: conservative, ondemand, userspace, powersave, performance
current policy: frequency should be within 800 MHz and 800 MHz.
The governor "userspace" may decide which speed to use
within this range.
current CPU frequency is 800 MHz (asserted by call to hardware).
analyzing CPU 1:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time: 1
hardware limits: 800 MHz - 2.00 GHz
available frequency steps: 2.00 GHz, 1.60 GHz, 1.20 GHz, 800 MHz
available cpufreq governors: conservative, ondemand, userspace, powersave, performance
current policy: frequency should be within 800 MHz and 800 MHz.
The governor "performance" may decide which speed to use
within this range.
current CPU frequency is 800 MHz (asserted by call to hardware).
Similar posts :
http://ubuntuforums.org/showthread.php?t=700865
http://bbs.archlinux.org/viewtopic.php?id=42208
https://bugzilla.redhat.com/show_bug.cgi?id=511840
http://swiss.ubuntuforums.org/showthread.php?t=1069429
http://www.archivum.info/ubuntu-bugs...Pad-T60p).html
http://www.mail-archive.com/ubuntu-b...sg1858658.html
https://bugs.launchpad.net/ubuntu/+s...22/+bug/132271
Bookmarks