[U-Boot-Users] watchdog api support

[Mike Frysinger]

the documentation for the watchdog seems to be on the non-existant side ... 
the toplevel mentions CONFIG_WATCHDOG, but there doesnt seem to be any 
internal documentation on what exactly this entails for people who want to 
implement a watchdog (the Blackfin processor has an on-chip watchdog)

looking at include/watchdog.h shows that there is also the (undocumented) 
CONFIG_HW_WATCHDOG option which implies CONFIG_WATCHDOG is only for software 
watchdogs (which the toplevel README doesnt mention)

sadly, the watchdog.h seems to have PPC-specific warts here (using the "bl" 
instruction in assembly), inconsistent defines for the reset function 
(trailing "()"), and the common API only covers a reset function ... there is 
no init function

usage wise, there seems to be a requirement that there be a periodic timer to 
reset the watchdog as well as the random sprinkling of calls 
to "WATCHDOG_RESET ()" through some core pieces of code.  there also doesnt 
seem to be information on what the standard expected timeout for the watchdog 
is ... 1 second ? 5 seconds ? a minute ?

and is it just me, or is doing something like:
void hw_watchdog_reset(void)
{
}
seem kind of stupid ?
-mike
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