Chapter 43
Watchdog (WDOG) Driver
43.1 Introduction
The Watchdog Timer module protects against system failures by providing an escape
from unexpected hang or infinite loop situations or programming errors.
Some platforms may have two WDOG modules with one of them having interrupt
capability.
43.1.1 Hardware Operation
Once the WDOG timer is activated, it must be serviced by software on a periodic basis.
If servicing does not take place in time, the WDOG times out. Upon a time-out, the
WDOG either asserts the wdog_b signal or a wdog_rst_b system reset signal, depending
on software configuration. The watchdog module cannot be deactivated once it is
activated.
43.1.2 Software Operation
The Linux OS has a standard WDOG interface that allows support of a WDOG driver for
a specific platform.
WDOG can be suspended/resumed in STOP/DOZE and WAIT modes independently.
Since some bits of the WGOD registers are only one-time programmable after booting,
ensure these registers are written correctly.
i.MX 6Solo/6DualLite Linux Reference Manual, Rev. L3.0.35_4.1.0, 09/2013
Freescale Semiconductor, Inc.
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