On Tue, May 27, 2008 at 06:27:58PM -0400, Mike Frysinger wrote: > On Tue, May 27, 2008 at 5:57 PM, David VomLehn wrote: > > Continuous Logging for Watchdog Timer Expiration > > ------------------------------------------------ > > We run with a watchdog timer that can reboot the system. When we reboot, we > > lose all of our status, making it very difficult to determine what went > > wrong. Fortunately, there is only one major cause of not refreshing the > > watchdog--a driver disabled interrupts for so long that the timer function > > that resets the watchdog timer never had a chance to run. So, a way to log > > what functions were enable and disabling interrupts on a continuous basis, > > along with a memory section that wouldn't be overwritten on reboot, would > > allow capturing the cause for these otherwise "silent" reboots. > > how do you propose addressing that ? hardware watchdogs reset the > hardware, so there is nothing software can do to recover information > like register state. as soon as the watchdog timer expires, the state > is gone forever. > -mike If I understand correctly David is talking about logging some trace-like info (so it exists before a HW watchdog expires), and having it somewhere "safe" from being disturbed by a HW reset. Tom -- /"\ ASCII Ribbon Campaign | \ / | Email to user 'CTZ001' X Against HTML | at 'email.mot.com' / \ in e-mail & news | -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
