On Thu, 22 Nov 2007, Thomas Renninger wrote: > I'd like to point you to some things I found out on ThinkPads the last > weeks: > > - IBM T41p shuts down, powersave, Temperature state changed to critical > https://bugzilla.novell.com/show_bug.cgi?id=333043 > > This affects a lot machines (T41(p), T42(p), T43(p), R40) > I expect the real culprit is a confused EC (one machine had the > problem, the other one not). > Anyway, it seems ACPI notifies had higher priority (or did not get > scheduled away) in former kernels. Therefore the BIOS could still > avoid a critical thermal shutdown through lowering CPU frequency > (_PPC) interface on older kernels, but something seem to have > changed there... Argh. Well, thinkpad-acpi fortunately has absolutely nothing to add to the picture (unless the misterious HKEY 0x6011/0x6012 events are actually thermal warning events). I kept well away from the standard thermal ACPI interface, since there didn't seem to be a reason to muck with it. Now I am not so sure anymore. What I do know: the T41 and T42 BIOSes and EC firmware *are the same*, down to the bit level. So if there is a difference between the T41 and T42 behaviour, it is very likely either a hardware fault, or one of the two is NOT using the latest BIOS. If they are indeed using the latest BIOS, it is a BIOS bug (the BIOS does know if it is in a T40, T41 or T42, and could act in a different way) in its SMI management routines. The only hope is to beg Lenovo for a fix. Thermal problems with the T4x are common, and if they developed after the machine was used for a few years (as opposed to a bad manufacturing issue that it had since day one), they are usually user-serviceable. Remove the entire heatsink assembly, and very carefully and very throughoutly replace any already existing or missing thermal glue with very high grade thermal cooling paste, the type you'd use for serious overclocking (Artic Silver 5 or better). Of course, check to make sure the fan is working properly. This is no milkrun, and it takes a few hours and a lot of patience if one wants to do it perfectly. Unless you are in a really hot place (35C or above), in my experience a T4x notebook with the entire heatsink system working at top condition does NOT reach critical temperatures, even while working at full CPU load. But it is really easy for a T4x to have their heatsink system at far below the top condition :( There is one thing I can help with. ThinkPad ACPI knows how to enable a "ludicrous speed" fan mode, aka "disengaged" mode or "full speed" mode, which is typically at least twice as fast as the highest fan mode the EC likes to trigger, even at thermal emergencies. Give me a trigger inside the kernel, and I will kick it on during thermal emergencies, regardless of fan_control status. Userspace already has control over this if fan_control=1 is specified on module load (just disable PWM through the hwmon interface, and it will kick the fan into full speed mode). But really, if you have a need of the full speed fan mode regularly, it either means your ThinkPad is in need of repair to the heatsink system, or it means you are in such a hot climate you'd better be playing at the beach instead of using a laptop. > - Latest Lenovo ThinkPads do not like ACPI EC writes for brightness > switching (s2ram broken) That's because you must not do EC writes to change brightness on these boxes :-) Latest thinkpad-acpi in ibm-acpi.sf.net should get this right already, and use only the UCMS ACPI method to modify brightness levels on Lenovo boxes. > I've been told it only happens when brightness is set above 7. > Don't know, but it seems to be the EC writes > 7 that lets the > machine not wake up anymore from a s2ram. Well, latest X.org really, really dislikes anyone messing with the backlight brightness behind its back, so make sure it is not related to that problem as well. I am starting to talk to the X.org people to see how I can be told by the X server that it is active, and completely switch thinkpad-acpi to "userspace is in control" backlight mode... > - Weird USB - EHCI IRQ problems on very latest Lenovo models > > Unhandled IRQ messages. Looks like an IRQ (from camera?) gets routed > to EHCI pin also? Don't know the details and I am also not very > familar with this..., Oliver might be able to point you to bug > reports, AFAIK there also exist kernel.org bugs. > This is not solved yet, AFAIK. > If anyone knows more about this problem, that would be great... Indeed. And if we do get precise enough descriptions of the issue, it is something that we should try to find a way to forward to Lenovo for a fix. > Attaching an USB device breaks USB and throws a calltrace > https://bugzilla.novell.com/show_bug.cgi?id=325601 > > As this seem to be a very (recent Lenovo) ThinkPad specific problem > -> Only happens on latest ThinkPads, but back to at least > kernel 2.6.16 until latest mainline... I hope to get some > feedback from Lenovo ThinkPad users also seeing this. Same comment as above. -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ ibm-acpi-devel mailing list ibm-acpi-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/ibm-acpi-devel
