ACPI on HP Pavilion dv2765tx, c-states problems

[Michael Sotnikov <astar@tut.by>]

Hi,

I hope, that I'm writing to the correct group. I've tried to find the
reason behind my problem, but didn't manage to.

The problem:
Can't start acpi_cpufreq ("No such device"), but p4_cpuclock driver
works well. In this case there is no c-state management (cpu is always
in C0).

I've decompiled dsdt - only some warnings about methods related to pci.
Checked _OSI() - nothing special.

There are errors in dmesg, related to cpu's info (truncated):
-----
[ 17.045653] ACPI Warning (tbutils-0217): Incorrect checksum in table 
[SSDT] -  E6, should be 38 [20070126]
....
[ 19.458760] ACPI Error (psargs-0355): [TS0T] Namespace lookup failure,
AE_NOT_FOUND
[ 19.458765] ACPI Error (psparse-0537): Method parse/execution failed
[\_PR_.CPU0._PDC] (Node f7c51b88), AE_NOT_FOUND
[ 19.459076] ACPI: CPU0 (power states: C1[C1] C2[C2] C3[C3])
[ 19.459278] ACPI: SSDT 7FED09A4, 00C8 (r1 PmRef Cpu1Ist 3000 INTL 20061109)
[ 19.459465] ACPI: SSDT 7FED06E7, 0085 (r1 PmRef Cpu1Cst 3000 INTL 20061109)
[ 19.459641] ACPI Error (psargs-0355): [\_PR_.CPU0._PPC] Namespace
lookup failure, AE_NOT_FOUND
[ 19.459645] ACPI Error (psparse-0537): Method parse/execution failed
[\_PR_.CPU1._PPC] (Node f7ccf180), AE_NOT_FOUND
[ 19.459895] ACPI Error (psargs-0355): [\_PR_.CPU0._CST] Namespace
lookup failure, AE_NOT_FOUND
[ 19.459899] ACPI Error (psparse-0537): Method parse/execution failed
[\_PR_.CPU1._CST] (Node f7ccf1f8), AE_NOT_FOUND
[ 19.459979] ACPI: CPU1 (power states: C1[C1] C2[C2] C3[C3])
--------

I've checked it with 2.6.25 kernel - same errors.
My main system (ubuntu 8.04):

$ uname -a
Linux astar-laptop 2.6.24-16-generic #1 SMP Thu Apr 10 13:23:42 UTC 2008 
i686 GNU/Linux

Is there any solutions, except waiting firmware update from laptop vendor?

Best regards,
Michael