| Message ID | 527A28CE.2070802@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wednesday 06 November 2013 06:32 AM, ivan.khoronzhuk wrote: > When watchdog timer is expired we can know about it thought > GET_STATUS ioctl option. > > Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> > --- Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
On 11/06/2013 03:32 AM, ivan.khoronzhuk wrote: > When watchdog timer is expired we can know about it thought thought -> through or with > GET_STATUS ioctl option. > > Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> > --- > drivers/watchdog/davinci_wdt.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c > index 6cbf2e1..a371b2d 100644 > --- a/drivers/watchdog/davinci_wdt.c > +++ b/drivers/watchdog/davinci_wdt.c > @@ -144,6 +144,18 @@ static unsigned int davinci_wdt_get_timeleft(struct watchdog_device *wdd) > return wdd->timeout - timer_counter; > } > > +static unsigned int davinci_wdt_status(struct watchdog_device *wdd) > +{ > + u32 val; > + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); > + > + val = ioread32(davinci_wdt->base + WDTCR); > + if (val & WDFLAG) > + return WDIOF_CARDRESET; > + "Card previously reset the CPU" Is this really accurate / correct ? My understanding is that the status is supposed to return the reason for a previous reset/reboot, not the curent condition. > + return 0; > +} > + > static const struct watchdog_info davinci_wdt_info = { > .options = WDIOF_KEEPALIVEPING, > .identity = "DaVinci Watchdog", > @@ -155,6 +167,7 @@ static const struct watchdog_ops davinci_wdt_ops = { > .stop = davinci_wdt_ping, > .ping = davinci_wdt_ping, > .get_timeleft = davinci_wdt_get_timeleft, > + .status = davinci_wdt_status, > }; > > static int davinci_wdt_probe(struct platform_device *pdev) >
On 11/17/2013 04:24 AM, Guenter Roeck wrote: > On 11/06/2013 03:32 AM, ivan.khoronzhuk wrote: >> When watchdog timer is expired we can know about it thought > > thought -> through or with > Ok >> GET_STATUS ioctl option. >> >> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> >> --- >> drivers/watchdog/davinci_wdt.c | 13 +++++++++++++ >> 1 file changed, 13 insertions(+) >> >> diff --git a/drivers/watchdog/davinci_wdt.c >> b/drivers/watchdog/davinci_wdt.c >> index 6cbf2e1..a371b2d 100644 >> --- a/drivers/watchdog/davinci_wdt.c >> +++ b/drivers/watchdog/davinci_wdt.c >> @@ -144,6 +144,18 @@ static unsigned int >> davinci_wdt_get_timeleft(struct watchdog_device *wdd) >> return wdd->timeout - timer_counter; >> } >> >> +static unsigned int davinci_wdt_status(struct watchdog_device *wdd) >> +{ >> + u32 val; >> + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); >> + >> + val = ioread32(davinci_wdt->base + WDTCR); >> + if (val & WDFLAG) >> + return WDIOF_CARDRESET; >> + > "Card previously reset the CPU" > > Is this really accurate / correct ? > > My understanding is that the status is supposed to return the reason for > a previous reset/reboot, > not the curent condition. > Actually it is not so good correlate with the purpose, but I grasped several examples like watchdog/pcwd.c; watchdog/w83977f_wdt.c; watchdog/of_xilinx_wdt.c and saw that I can use it in meaning "the card initiated reset. After the WDT is overflowed it sets WDFLAG, so I can use it. It is more useful while debugging and if it is doubtful I can drop it. >> + return 0; >> +} >> + >> static const struct watchdog_info davinci_wdt_info = { >> .options = WDIOF_KEEPALIVEPING, >> .identity = "DaVinci Watchdog", >> @@ -155,6 +167,7 @@ static const struct watchdog_ops davinci_wdt_ops = { >> .stop = davinci_wdt_ping, >> .ping = davinci_wdt_ping, >> .get_timeleft = davinci_wdt_get_timeleft, >> + .status = davinci_wdt_status, >> }; >> >> static int davinci_wdt_probe(struct platform_device *pdev) >> >
On Mon, Nov 18, 2013 at 04:21:06PM +0200, ivan.khoronzhuk wrote: > On 11/17/2013 04:24 AM, Guenter Roeck wrote: > > On 11/06/2013 03:32 AM, ivan.khoronzhuk wrote: > >> When watchdog timer is expired we can know about it thought > > > > thought -> through or with > > > > Ok > > >> GET_STATUS ioctl option. > >> > >> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> > >> --- > >> drivers/watchdog/davinci_wdt.c | 13 +++++++++++++ > >> 1 file changed, 13 insertions(+) > >> > >> diff --git a/drivers/watchdog/davinci_wdt.c > >> b/drivers/watchdog/davinci_wdt.c > >> index 6cbf2e1..a371b2d 100644 > >> --- a/drivers/watchdog/davinci_wdt.c > >> +++ b/drivers/watchdog/davinci_wdt.c > >> @@ -144,6 +144,18 @@ static unsigned int > >> davinci_wdt_get_timeleft(struct watchdog_device *wdd) > >> return wdd->timeout - timer_counter; > >> } > >> > >> +static unsigned int davinci_wdt_status(struct watchdog_device *wdd) > >> +{ > >> + u32 val; > >> + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); > >> + > >> + val = ioread32(davinci_wdt->base + WDTCR); > >> + if (val & WDFLAG) > >> + return WDIOF_CARDRESET; > >> + > > "Card previously reset the CPU" > > > > Is this really accurate / correct ? > > > > My understanding is that the status is supposed to return the reason for > > a previous reset/reboot, > > not the curent condition. > > > > Actually it is not so good correlate with the purpose, but I grasped > several examples like watchdog/pcwd.c; watchdog/w83977f_wdt.c; > watchdog/of_xilinx_wdt.c and saw that I can use it in meaning "the card initiated reset. > After the WDT is overflowed it sets WDFLAG, so I can use it. > It is more useful while debugging and if it is doubtful I can drop it. > The usual reaction to a watchdog timer event is a reset, so I am somewhat doubtful if this is of any use in practice, other than maybe to show that it isn't working. Anyway, I always dislike it when people point out other wrong usages of an API (or anything, really) as argument to do the same. Speeding isn't legal either, no matter how many people do it. FWIW, the wrong usages you pointed out should in my opinion be removed, and if Wim agrees I'll be happy to submit patches to do it. If you need debugging information, there is always debugfs. There should be no need to hijack an API which is supposed to be used for something else. Guenter
On 11/18/2013 06:24 PM, Guenter Roeck wrote: > On Mon, Nov 18, 2013 at 04:21:06PM +0200, ivan.khoronzhuk wrote: >> On 11/17/2013 04:24 AM, Guenter Roeck wrote: >>> On 11/06/2013 03:32 AM, ivan.khoronzhuk wrote: >>>> When watchdog timer is expired we can know about it thought >>> >>> thought -> through or with >>> >> >> Ok >> >>>> GET_STATUS ioctl option. >>>> >>>> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> >>>> --- >>>> drivers/watchdog/davinci_wdt.c | 13 +++++++++++++ >>>> 1 file changed, 13 insertions(+) >>>> >>>> diff --git a/drivers/watchdog/davinci_wdt.c >>>> b/drivers/watchdog/davinci_wdt.c >>>> index 6cbf2e1..a371b2d 100644 >>>> --- a/drivers/watchdog/davinci_wdt.c >>>> +++ b/drivers/watchdog/davinci_wdt.c >>>> @@ -144,6 +144,18 @@ static unsigned int >>>> davinci_wdt_get_timeleft(struct watchdog_device *wdd) >>>> return wdd->timeout - timer_counter; >>>> } >>>> >>>> +static unsigned int davinci_wdt_status(struct watchdog_device *wdd) >>>> +{ >>>> + u32 val; >>>> + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); >>>> + >>>> + val = ioread32(davinci_wdt->base + WDTCR); >>>> + if (val & WDFLAG) >>>> + return WDIOF_CARDRESET; >>>> + >>> "Card previously reset the CPU" >>> >>> Is this really accurate / correct ? >>> >>> My understanding is that the status is supposed to return the reason for >>> a previous reset/reboot, >>> not the curent condition. >>> >> >> Actually it is not so good correlate with the purpose, but I grasped >> several examples like watchdog/pcwd.c; watchdog/w83977f_wdt.c; >> watchdog/of_xilinx_wdt.c and saw that I can use it in meaning "the card initiated reset. >> After the WDT is overflowed it sets WDFLAG, so I can use it. >> It is more useful while debugging and if it is doubtful I can drop it. >> > The usual reaction to a watchdog timer event is a reset, so I am somewhat > doubtful if this is of any use in practice, other than maybe to show that it > isn't working. > > Anyway, I always dislike it when people point out other wrong usages of an API > (or anything, really) as argument to do the same. Speeding isn't legal either, > no matter how many people do it. FWIW, the wrong usages you pointed out should > in my opinion be removed, and if Wim agrees I'll be happy to submit patches to > do it. > > If you need debugging information, there is always debugfs. There should be > no need to hijack an API which is supposed to be used for something else. > > Guenter > I'll drop it
diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c index 6cbf2e1..a371b2d 100644 --- a/drivers/watchdog/davinci_wdt.c +++ b/drivers/watchdog/davinci_wdt.c @@ -144,6 +144,18 @@ static unsigned int davinci_wdt_get_timeleft(struct watchdog_device *wdd) return wdd->timeout - timer_counter; } +static unsigned int davinci_wdt_status(struct watchdog_device *wdd) +{ + u32 val; + struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd); + + val = ioread32(davinci_wdt->base + WDTCR); + if (val & WDFLAG) + return WDIOF_CARDRESET; + + return 0; +} + static const struct watchdog_info davinci_wdt_info = { .options = WDIOF_KEEPALIVEPING, .identity = "DaVinci Watchdog", @@ -155,6 +167,7 @@ static const struct watchdog_ops davinci_wdt_ops = { .stop = davinci_wdt_ping, .ping = davinci_wdt_ping, .get_timeleft = davinci_wdt_get_timeleft, + .status = davinci_wdt_status, }; static int davinci_wdt_probe(struct platform_device *pdev)
When watchdog timer is expired we can know about it thought GET_STATUS ioctl option. Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com> --- drivers/watchdog/davinci_wdt.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)