On Fri, Jan 18, 2008 at 06:06:24PM -0700, Jordan Crouse wrote: > As promised, a watchdog driver for the Geode GX/LX processors is attached. > I basically just ported the previous patch forward to 2.6.24. > > I also have good news or bad news depending on your perspective. I wanted > to test this against 2.6.24, and OLPC is stuck at an older kernel version, > so I had to test this with coreboot (LinuxBIOS) on another Geode > platform. Like all BIOSen execpt for the OLPC firmware, coreboot uses > VSA (SMM handler) which consumes all the timers.
Hmm, the Geode LX platform I work with uses VSA/SMM and I have had no problems using timer 2 for a watchdog. Some of the timers are certainly already setup by something in the BIOS, but quite a few are not in use. The board I am using is the compulab iGLX module. I did have to mangle together a watchdog driver myself some time ago since there wasn't one for the Geode LX at the time. Of course I haven't gone past 2.6.18 kernel for now (I am tracking Debian stable for the most part), so I have no idea if something in a newer kernel breaks things. > So I used the magical MSR and surprise! - the timer tick hung. > I compiled out the timer tick, and tested the watchdog timer instead, > and it worked fine on timer 0. So I don't think the MFGPTs themselves > have anything to do with this problem, but I do think it might be > related to VSA and possibly interrupts too. I'm going to invoke the > strong BIOS fu of our LinuxBIOS / BIOS expert Marc Jones, and see what > he comes up with. > > I don't know how much of a hassle it would be for Andres to get a 2.6.24 > kernel running on the OLPC to make sure that this isn't a regression > in the timer tick code (I suspect it isn't a regression, but you never > know). I also think that it would probably be in our best interest to > default CONFIG_GEODE_MFGPT_TIMER to 'n' until we get this figured > out. Since most BIOSen don't have timers available, that shouldn't affect > too many people. > > So, anyway, enjoy the watchdog timer - I hope it meets everybody's > expectations for the 2.6.25 kernel. -- Len Sorensen -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
