Any idea, how to eanble Watchdog timer for 2.4 Linux Kernel

Enabling the WDT depends on how the WDT is implemented in your particular hardware platform, and whether or not the standard Linux kernel has support for it.

And whether kernel support makes a damn bit of difference -- if the WDT on your hardware just pulls the reset line and flushes the whole app down the toilet then all you need is access to the relevant registers and an app that kicks the dog. The kernel wouldn't necessarily have to get involved at all.

Somehow I suspect that the "right" way to do this would involve some custom kernel code.

--
Tim Wescott
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Google is your friend: "Linux WDT" gets 107,000 hits.

It does make a difference - if it's a supported piece of WDT hardware, then Linux already has a driver that provides a [standardized] API to enable and kick the dog. So all he has to do is set the right kernel config option and rebuild.

BUT are any of them worthwhile and/or accurate? An OS is not an active thing, it is purely a passive servant.

--
 
 
 
                        cbfalconer at maineline dot net

(I *knew* you existed!)

AFAIU, 2.4 does support a few watchdogs: cf.

238 comment 'Watchdog Cards' 239 bool 'Watchdog Timer Support' CONFIG_WATCHDOG 240 if [ "$CONFIG_WATCHDOG" != "n" ]; then 241 bool ' Disable watchdog shutdown on close' CONFIG_WATCHDOG_NOWAYOUT 242 tristate ' Acquire SBC Watchdog Timer' CONFIG_ACQUIRE_WDT 243 tristate ' Advantech SBC Watchdog Timer' CONFIG_ADVANTECH_WDT 244 tristate ' ALi M7101 PMU on ALi 1535D+ Watchdog Timer' CONFIG_ALIM1535_WDT 245 tristate ' ALi M7101 PMU Watchdog Timer' CONFIG_ALIM7101_WDT 246 tristate ' AMD "Elan" SC520 Watchdog Timer' CONFIG_SC520_WDT 247 tristate ' Berkshire Products PC Watchdog' CONFIG_PCWATCHDOG 248 if [ "$CONFIG_FOOTBRIDGE" = "y" ]; then 249 tristate ' DC21285 watchdog' CONFIG_21285_WATCHDOG 250 if [ "$CONFIG_ARCH_NETWINDER" = "y" ]; then 251 tristate ' NetWinder WB83C977 watchdog' CONFIG_977_WATCHDOG 252 fi 253 fi 254 tristate ' Eurotech CPU-1220/1410 Watchdog Timer' CONFIG_EUROTECH_WDT 255 tristate ' IB700 SBC Watchdog Timer' CONFIG_IB700_WDT 256 tristate ' ICP ELectronics Wafer 5823 Watchdog' CONFIG_WAFER_WDT 257 tristate ' Intel i810 TCO timer / Watchdog' CONFIG_I810_TCO 258 tristate ' Mixcom Watchdog' CONFIG_MIXCOMWD 259 tristate ' SBC-60XX Watchdog Timer' CONFIG_60XX_WDT 260 dep_tristate ' SC1200 Watchdog Timer (EXPERIMENTAL)' CONFIG_SC1200_WDT $CONFIG_EXPERIMENTAL 261 tristate ' NatSemi SCx200 Watchdog' CONFIG_SCx200_WDT 262 tristate ' Software Watchdog' CONFIG_SOFT_WATCHDOG 263 tristate ' W83877F (EMACS) Watchdog Timer' CONFIG_W83877F_WDT 264 tristate ' WDT Watchdog timer' CONFIG_WDT 265 tristate ' WDT PCI Watchdog timer' CONFIG_WDTPCI 266 if [ "$CONFIG_WDT" != "n" ]; then 267 bool ' WDT501 features' CONFIG_WDT_501 268 if [ "$CONFIG_WDT_501" = "y" ]; then 269 bool ' Fan Tachometer' CONFIG_WDT_501_FAN 270 fi 271 fi 272 tristate ' ZF MachZ Watchdog' CONFIG_MACHZ_WDT 273 if [ "$CONFIG_SGI_IP22" = "y" ]; then 274 dep_tristate ' Indy/I2 Hardware Watchdog' CONFIG_INDYDOG $CONFIG_SGI_IP22 275 fi 276 if [ "$CONFIG_8xx" = "y" ]; then 277 tristate ' MPC8xx Watchdog Timer' CONFIG_8xx_WDT 278 fi 279 fi

(The latest 2.4.35 even added a few more)

2.6 supports even more: