Re: [PATCH v10 5/5] Watchdog: ARM SBSA Generic Watchdog half timeout panic support

From: Thomas Petazzoni
Date: Fri Feb 05 2016 - 08:33:26 EST


Hello,

On Fri, 5 Feb 2016 07:08:23 -0600, Timur Tabi wrote:

> > I'm quite certainly missing something completely obvious here, but how
> > can you get the WS1 interrupt*after* raising a panic? Aren't all
> > interrupts disabled and the system fully halted once you get a panic(),
> > especially when raised from an interrupt handler? If that's the case,
> > how can the system continue to do things, such as receiving the WS1
> > interrupt and resetting ?
>
> Typically, WS1 is not an interrupt. Instead, it's a hard system-level
> reset.

Ah, right, true. I missed that aspect because on my HW, triggering a
system-level reset on WS1 is optional. I can actually get an interrupt
on both WS0 and WS1, and no reset at all.

But a normal configuration indeed involves having the WS1 event
configured in HW to be a system-level reset.

So, OK, it makes sense. Thanks for the clarification!

Thomas
--
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com