diff mbox series

powerpc: allow opting out of WATCHDOG_RESET() from timer interrupt

Message ID 20200316211551.30042-1-rasmus.villemoes@prevas.dk
State Superseded
Headers show
Series powerpc: allow opting out of WATCHDOG_RESET() from timer interrupt | expand

Commit Message

Rasmus Villemoes March 16, 2020, 9:15 p.m. UTC 
When using CONFIG_(SPL_)WDT, the watchdog_reset function is a lot more
complicated than just poking a few SOC-specific registers - it
involves accessing all kinds of global data, and if the interrupt
happens at the wrong time (say, in the middle of an WATCHDOG_RESET()
call from ordinary code), that can end up corrupting said global data.

Also, having WATCHDOG_RESET() called automatically from the timer
interrupt runs counter to the idea of a watchdog device - if the board
runs into an infinite loops with interrupts still enabled, the
watchdog will never fire.

Allow the board to opt out of this behaviour by setting
CONFIG_SYS_WATCHDOG_FREQ to 0 - as that setting is currently
nonsensical, it cannot affect any existing boards.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
---
 arch/powerpc/lib/interrupts.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/powerpc/lib/interrupts.c b/arch/powerpc/lib/interrupts.c
index 64ee0cc210..23ac5bca1e 100644
--- a/arch/powerpc/lib/interrupts.c
+++ b/arch/powerpc/lib/interrupts.c
@@ -79,7 +79,7 @@  void timer_interrupt(struct pt_regs *regs)
 	timestamp++;
 
 #if defined(CONFIG_WATCHDOG) || defined (CONFIG_HW_WATCHDOG)
-	if ((timestamp % (CONFIG_SYS_WATCHDOG_FREQ)) == 0)
+	if (CONFIG_SYS_WATCHDOG_FREQ && (timestamp % (CONFIG_SYS_WATCHDOG_FREQ)) == 0)
 		WATCHDOG_RESET ();
 #endif    /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */