Distribution: Gentoo Hardware Environment: Toshiba 2250CDT (laptop) Celeron Coppermine 600Mhz 192MB RAM (output of lspci below) Software Environment: ACPI 1.6 (according to BIOS, latest BIOS upgrade) acpid 1.0.2 Problem Description: Very strange bug;when I switch to "stanby" sleep state (S1), the processor speed, probably to save power, drops significantly (from 600mhz to 80mhz according to x86info -mhz). The problem is that the frequency never goes back to normal when the computer return from his sleep. /proc/cpuinfo shows no change, but the decrease of speed is evident. Also, the processor power state switched from C2 to C1 once it gets back from standby. I don't know if this is normal but the processor never uses C1 otherwise; cat /proc/acpi/processor/CPU0/power (see below) always shows me the processor is in "C2" state unless I try to standby. C1 state however always has some "counts" (but something like .0001% of C2). There seems to be no way to bring back processor into C2 unless I reboot. Please note this laptop doesn't support CPU frequency scaling (sadly). Also, the ACPI version is very primitive, with the latest BIOS, it uses ACPI 1.6. I have to force the use of ACPI (acpi=force flag while booting) or the kernel doesn't recognize this computer as ACPI capable (APM has some bad bugs too so I prefer to use ACPI). Steps to reproduce: echo "1" > /proc/acpi/sleep (feel free to ask if you need any more info)
Created attachment 3814 [details] output of dmesg -s40000
Created attachment 3815 [details] output of dmidecode
Created attachment 3816 [details] output of acpidmp
Created attachment 3817 [details] output of lspci -vv
Created attachment 3818 [details] output of /proc/interrupts
Created attachment 3819 [details] output of /proc/acpi/processor/CPU0/power AFTER stanby
still a problem in 2.6.9 or later?
Yes. 2.6.9 does the same bug. It's worst with 2.6.10-rc2, the computer doesn't even come back from standby, the "state" lid turn to green but nothing else happen and the computer doesn't even answer to ping.
What driver (if any) are you using to change the frequency. Can you give me the output of all the files under /sys/devices/system/cpu/cpu0/cpufreq (if one exists)
No driver for frequency and there is nothing in /sys/devices/system/cpu/cpu0/cpufreq, the laptop does not support cpu throlling. The bug seems to be related to power state ( /proc/acpi/processor/CPU0/power ), as the CPU frequency seems to drop when it use "C2" power state. Somehow, it stick to C2 when it come back from standby. Note that the problem seems to be fixed in earlier kernel. Kernel earlier than 2.6.12 ( ? ) don't get this bug, or at least, I haven't seen it so far.
Is this C2 issue still present with latest kernel. Please reopen the bug if the issue is still there. Thanks.