* [PATCH 1/1] watchdog: sp805: ping fails to abort wdt reset
@ 2016-01-19 6:04 Sandeep Tripathy
2016-01-19 6:53 ` Viresh Kumar
0 siblings, 1 reply; 4+ messages in thread
From: Sandeep Tripathy @ 2016-01-19 6:04 UTC (permalink / raw)
To: wim
Cc: viresh.kumar, linux-watchdog, linux-kernel,
bcm-kernel-feedback-list, Sandeep Tripathy
sp805 wdt asserts interrupt for the first expiry and
reloads the counter. If wdt interrupt is set and count
reaches zero then wdt reset event is generated.To get
wdt reset at t timeout the driver loads wdt counter
with t/2. A ping before t second *should* prevent wdt
reset. Currently if ping is done after t/2 sec then
wdt interrupt condition gets set. On the next countdown
of loadval wdt reset event occurs eventhough wdt was
reloaded before the set timeout t.
This patch clears the interrupt condition on ping.
Signed-off-by: Sandeep Tripathy <tripathy@broadcom.com>
---
drivers/watchdog/sp805_wdt.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
index 01d8162..e7a715e 100644
--- a/drivers/watchdog/sp805_wdt.c
+++ b/drivers/watchdog/sp805_wdt.c
@@ -139,12 +139,11 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
+ writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
- if (!ping) {
- writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
+ if (!ping)
writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
WDTCONTROL);
- }
writel_relaxed(LOCK, wdt->base + WDTLOCK);
--
1.7.9.5
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] watchdog: sp805: ping fails to abort wdt reset
2016-01-19 6:04 [PATCH 1/1] watchdog: sp805: ping fails to abort wdt reset Sandeep Tripathy
@ 2016-01-19 6:53 ` Viresh Kumar
2016-01-19 7:11 ` Guenter Roeck
0 siblings, 1 reply; 4+ messages in thread
From: Viresh Kumar @ 2016-01-19 6:53 UTC (permalink / raw)
To: Sandeep Tripathy
Cc: wim, linux-watchdog, linux-kernel, bcm-kernel-feedback-list
On 19-01-16, 11:34, Sandeep Tripathy wrote:
> sp805 wdt asserts interrupt for the first expiry and
Why an extra space before sp805 ?
> reloads the counter. If wdt interrupt is set and count
> reaches zero then wdt reset event is generated.To get
Add space after full-stop.
> wdt reset at t timeout the driver loads wdt counter
Keep t and t/2 in single quotes, its hardly readable otherwise.
> with t/2. A ping before t second *should* prevent wdt
> reset. Currently if ping is done after t/2 sec then
> wdt interrupt condition gets set. On the next countdown
> of loadval wdt reset event occurs eventhough wdt was
> reloaded before the set timeout t.
>
> This patch clears the interrupt condition on ping.
Why extra spaces before 'This'?
>
> Signed-off-by: Sandeep Tripathy <tripathy@broadcom.com>
> ---
> drivers/watchdog/sp805_wdt.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
> index 01d8162..e7a715e 100644
> --- a/drivers/watchdog/sp805_wdt.c
> +++ b/drivers/watchdog/sp805_wdt.c
> @@ -139,12 +139,11 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
>
> writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
> writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
> + writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
>
> - if (!ping) {
> - writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
> + if (!ping)
> writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
> WDTCONTROL);
> - }
>
> writel_relaxed(LOCK, wdt->base + WDTLOCK);
If I read the TRM properly, then you don't need to load the WDTLOAD
register on ping and so your change can be written as:
diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
index 01d816251302..42e1ec86532d 100644
--- a/drivers/watchdog/sp805_wdt.c
+++ b/drivers/watchdog/sp805_wdt.c
@@ -138,10 +138,10 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
spin_lock(&wdt->lock);
writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
- writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
+ writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
if (!ping) {
- writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
+ writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
WDTCONTROL);
}
Please try if this works or not.
--
viresh
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] watchdog: sp805: ping fails to abort wdt reset
2016-01-19 6:53 ` Viresh Kumar
@ 2016-01-19 7:11 ` Guenter Roeck
2016-01-19 7:17 ` Viresh Kumar
0 siblings, 1 reply; 4+ messages in thread
From: Guenter Roeck @ 2016-01-19 7:11 UTC (permalink / raw)
To: Viresh Kumar, Sandeep Tripathy
Cc: wim, linux-watchdog, linux-kernel, bcm-kernel-feedback-list
On 01/18/2016 10:53 PM, Viresh Kumar wrote:
> On 19-01-16, 11:34, Sandeep Tripathy wrote:
>> sp805 wdt asserts interrupt for the first expiry and
>
> Why an extra space before sp805 ?
>
>> reloads the counter. If wdt interrupt is set and count
>> reaches zero then wdt reset event is generated.To get
>
> Add space after full-stop.
>
>> wdt reset at t timeout the driver loads wdt counter
>
> Keep t and t/2 in single quotes, its hardly readable otherwise.
>
>> with t/2. A ping before t second *should* prevent wdt
>> reset. Currently if ping is done after t/2 sec then
>> wdt interrupt condition gets set. On the next countdown
>> of loadval wdt reset event occurs eventhough wdt was
>> reloaded before the set timeout t.
>>
>> This patch clears the interrupt condition on ping.
>
> Why extra spaces before 'This'?
>
>>
>> Signed-off-by: Sandeep Tripathy <tripathy@broadcom.com>
>> ---
>> drivers/watchdog/sp805_wdt.c | 5 ++---
>> 1 file changed, 2 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
>> index 01d8162..e7a715e 100644
>> --- a/drivers/watchdog/sp805_wdt.c
>> +++ b/drivers/watchdog/sp805_wdt.c
>> @@ -139,12 +139,11 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
>>
>> writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
>> writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
>> + writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
>>
>> - if (!ping) {
>> - writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
>> + if (!ping)
>> writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
>> WDTCONTROL);
>> - }
>>
>> writel_relaxed(LOCK, wdt->base + WDTLOCK);
>
> If I read the TRM properly, then you don't need to load the WDTLOAD
> register on ping and so your change can be written as:
>
> diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
> index 01d816251302..42e1ec86532d 100644
> --- a/drivers/watchdog/sp805_wdt.c
> +++ b/drivers/watchdog/sp805_wdt.c
> @@ -138,10 +138,10 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
> spin_lock(&wdt->lock);
>
> writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
> - writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
> + writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
>
> if (!ping) {
> - writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
> + writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
> writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
> WDTCONTROL);
> }
>
That would require additional changes. Reason is that the load value is not immediately
written after a timeout change, but only with the next ping (which happens immediately
afterwards). With your proposed change, the load value would never be updated.
Besides, that would be a separate change, and would require a separate patch.
Guenter
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH 1/1] watchdog: sp805: ping fails to abort wdt reset
2016-01-19 7:11 ` Guenter Roeck
@ 2016-01-19 7:17 ` Viresh Kumar
0 siblings, 0 replies; 4+ messages in thread
From: Viresh Kumar @ 2016-01-19 7:17 UTC (permalink / raw)
To: Guenter Roeck
Cc: Sandeep Tripathy, wim, linux-watchdog, linux-kernel,
bcm-kernel-feedback-list
On 18-01-16, 23:11, Guenter Roeck wrote:
> On 01/18/2016 10:53 PM, Viresh Kumar wrote:
> >On 19-01-16, 11:34, Sandeep Tripathy wrote:
> >> sp805 wdt asserts interrupt for the first expiry and
> >
> >Why an extra space before sp805 ?
> >
> >>reloads the counter. If wdt interrupt is set and count
> >>reaches zero then wdt reset event is generated.To get
> >
> >Add space after full-stop.
> >
> >>wdt reset at t timeout the driver loads wdt counter
> >
> >Keep t and t/2 in single quotes, its hardly readable otherwise.
> >
> >>with t/2. A ping before t second *should* prevent wdt
> >>reset. Currently if ping is done after t/2 sec then
> >>wdt interrupt condition gets set. On the next countdown
> >>of loadval wdt reset event occurs eventhough wdt was
> >>reloaded before the set timeout t.
> >>
> >> This patch clears the interrupt condition on ping.
> >
> >Why extra spaces before 'This'?
> >
> >>
> >>Signed-off-by: Sandeep Tripathy <tripathy@broadcom.com>
> >>---
> >> drivers/watchdog/sp805_wdt.c | 5 ++---
> >> 1 file changed, 2 insertions(+), 3 deletions(-)
> >>
> >>diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
> >>index 01d8162..e7a715e 100644
> >>--- a/drivers/watchdog/sp805_wdt.c
> >>+++ b/drivers/watchdog/sp805_wdt.c
> >>@@ -139,12 +139,11 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
> >>
> >> writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
> >> writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
> >>+ writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
> >>
> >>- if (!ping) {
> >>- writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
> >>+ if (!ping)
> >> writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
> >> WDTCONTROL);
> >>- }
> >>
> >> writel_relaxed(LOCK, wdt->base + WDTLOCK);
> >
> >If I read the TRM properly, then you don't need to load the WDTLOAD
> >register on ping and so your change can be written as:
> >
> >diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
> >index 01d816251302..42e1ec86532d 100644
> >--- a/drivers/watchdog/sp805_wdt.c
> >+++ b/drivers/watchdog/sp805_wdt.c
> >@@ -138,10 +138,10 @@ static int wdt_config(struct watchdog_device *wdd, bool ping)
> > spin_lock(&wdt->lock);
> >
> > writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
> >- writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
> >+ writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
> >
> > if (!ping) {
> >- writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
> >+ writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
> > writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base +
> > WDTCONTROL);
> > }
> >
>
> That would require additional changes. Reason is that the load value is not immediately
> written after a timeout change, but only with the next ping (which happens immediately
> afterwards). With your proposed change, the load value would never be updated.
>
> Besides, that would be a separate change, and would require a separate patch.
Hmm, maybe then we can keep the original patch as is :)
@Sandeep: Please resend your patch after fixing the commit log and not
the diff.
--
viresh
^ permalink raw reply [flat|nested] 4+ messages in thread
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2016-01-19 6:04 [PATCH 1/1] watchdog: sp805: ping fails to abort wdt reset Sandeep Tripathy
2016-01-19 6:53 ` Viresh Kumar
2016-01-19 7:11 ` Guenter Roeck
2016-01-19 7:17 ` Viresh Kumar
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