>-----Original Message----- >From: Sune Mølgaard [mailto:sune@xxxxxxxxxxxx] >Sent: Thursday, October 19, 2006 11:19 AM >To: Pallipadi, Venkatesh >Cc: Jiri Slaby; Linux kernel mailing list; linux-acpi@xxxxxxxxxxxxxxx >Subject: Re: speedstep-centrino: ENODEV > >Thanks for taking an interest, if I haven't said so before. > >Now, I was about to write that I couldn't open /dev/mem, but luckily >remembered to try sudo'ing acpidump :-$ > >Enclosed is the dump, created while running 2.6.18.1. > OK. Things seem to be fine with the BIOS. You said it was working with 2.6.15. Do you remember whether kernel was using acpi-cpufreq or speedstep-centrino? One change that has happened in this region is that If your BIOS supports both speedstep-centrino and acpi-cpufreq, with 2.6.15 any one of those drivers would have worked. But now with 2.6.18, acpi-cpufreq will not work in the above case and you have to use speedstep_centrino. This was done because, speedstep-centrino has more features than acpi-cpufreq and also doing this helped to elimiate issues with lot of systems with kernel trying to do multiple ACPI PDC writes when BIOS doesn't expect it to. In short: (1) If you were using acpi-cpufreq in 2.6.15, there is a high chance that it wont work with 2.6.18 and you should be able to use speedstep-centrino in its place. Make sure you have properly configured speedstep-centrino (You should select X86_SPEEDSTEP_CENTRINO_ACPI along with X86_SPEEDSTEP_CENTRINO). (2) If you were using speedstep-centrino in 2.6.15 and now it doesn't work with 2.6.18, then we have a new regression here and we need to root cause it further by enabling cpufreq.debug and getting more debug messages to see where it is failing.... Thanks, Venki - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
