R-Car/Boards/Yocto-Gen3-CommonFAQ/How to use Watchdog timer.
How to use Watchdog timer.
Start/Reset timer:
ex) using echo:
echo > /dev/watchdog
End timer:
ex) using echo:
echo "V" > /dev/watchdog
After the timeouts(default: 60 seconds), device reboots.
How to change timeout-sec
Example(Yocto v3.21.0)
bitbake linux-renesas
vim ${WORK}/build/tmp/work-shared/h3ulcb/kernel-source/arch/arm64/boot/dts/renesas/r8a7795-h3ulcb.dts
# add following lines:
```
&rwdt {
timeoout-sec = <10>;
};
```
cd ${WORK}/build/tmp/work-shared/h3ulcb/kernel-source/
git add arch/arm64/boot/dts/renesas/r8a7795-h3ulcb.dts
git commit -m "arm64: dts: r8a7795-h3ulcb.dts: Add timeout-sec = <10>"
git format-patch -1
cp ./0001-arm64-dts-r8a7795-h3ulcb.dts-Add-timeout-sec-10.patch \
${WORK}/meta-renesas/meta-rcar-gen3/recipes-kernel/linux/linux-renesas/
echo -e 'SRC_URI_append = "\\\n file://0001-arm64-dts-r8a7795-h3ulcb.dts-Add-timeout-sec-10.patch\\\n"' \
> ${WORK}/meta-renesas/meta-rcar-gen3/recipes-kernel/linux/linux-renesas_4.14.bbappend
bitbake linux-renesas
See also: