| Message ID | 20240403212426.582727-1-jm@ti.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | watchdog: rti_wdt: Set min_hw_heartbeat_ms to accommodate 5% safety margin | expand |
Hello Judith, On Wed, Apr 03, 2024 at 04:24:26PM -0500, Judith Mendez wrote: > On AM62x, the watchdog is pet before the valid window > is open. Fix min_hw_heartbeat and accommodate a 5% safety Fix => Add Fixes tag + Cc:stable ? Thanks, Francesco
Hi Francesco, On 4/4/24 3:28 AM, Francesco Dolcini wrote: > Hello Judith, > > On Wed, Apr 03, 2024 at 04:24:26PM -0500, Judith Mendez wrote: >> On AM62x, the watchdog is pet before the valid window >> is open. Fix min_hw_heartbeat and accommodate a 5% safety > > Fix => Add Fixes tag + Cc:stable ? Thanks will add for v2 ~ Judith > > Thanks, > Francesco >
On 03/04/2024 18:24, Judith Mendez wrote: > On AM62x, the watchdog is pet before the valid window > is open. Fix min_hw_heartbeat and accommodate a 5% safety > margin with the exception of open window size < 10%, > which shall use <5% due to the smaller open window size. > > Signed-off-by: Judith Mendez <jm@ti.com> > --- > drivers/watchdog/rti_wdt.c | 24 +++++++++++++----------- > 1 file changed, 13 insertions(+), 11 deletions(-) > > diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c > index 8e1be7ba0103..0b16ada659cc 100644 > --- a/drivers/watchdog/rti_wdt.c > +++ b/drivers/watchdog/rti_wdt.c > @@ -92,7 +92,7 @@ static int rti_wdt_start(struct watchdog_device *wdd) > * to be 50% or less than that; we obviouly want to configure the open > * window as large as possible so we select the 50% option. > */ > - wdd->min_hw_heartbeat_ms = 500 * wdd->timeout; > + wdd->min_hw_heartbeat_ms = 550 * wdd->timeout; > > /* Generate NMI when wdt expires */ > writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL); > @@ -126,31 +126,33 @@ static int rti_wdt_setup_hw_hb(struct watchdog_device *wdd, u32 wsize) > * be petted during the open window; not too early or not too late. > * The HW configuration options only allow for the open window size > * to be 50% or less than that. > + * To avoid any glitches, we accommodate 5% safety margin, with the > + * exception of open window size < 10%. > */ > switch (wsize) { > case RTIWWDSIZE_50P: > - /* 50% open window => 50% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 500 * heartbeat; > + /* 50% open window => 55% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 550 * heartbeat; > break; > > case RTIWWDSIZE_25P: > - /* 25% open window => 75% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 750 * heartbeat; > + /* 25% open window => 80% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 800 * heartbeat; > break; > > case RTIWWDSIZE_12P5: > - /* 12.5% open window => 87.5% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 875 * heartbeat; > + /* 12.5% open window => 92.5% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 925 * heartbeat; > break; > > case RTIWWDSIZE_6P25: > - /* 6.5% open window => 93.5% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 935 * heartbeat; > + /* 6.5% open window => 96.5% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 965 * heartbeat; > break; > > case RTIWWDSIZE_3P125: > - /* 3.125% open window => 96.9% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 969 * heartbeat; > + /* 3.125% open window => 97.9% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 979 * heartbeat; > break; > > default: I tested this patch by enabling the systemd watchdog adding RuntimeWatchdogSec=30 to system.conf on a Verdin AM62. This setup causes watchdog resets without the patch, and with the patch applied I didn't see any watchdog related reboots. Tested-by: Rafael Beims <rafael.beims@toradex.com> Rafael
On Wed, Apr 03, 2024 at 04:24:26PM -0500, Judith Mendez wrote: > On AM62x, the watchdog is pet before the valid window > is open. Fix min_hw_heartbeat and accommodate a 5% safety > margin with the exception of open window size < 10%, > which shall use <5% due to the smaller open window size. > > Signed-off-by: Judith Mendez <jm@ti.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > drivers/watchdog/rti_wdt.c | 24 +++++++++++++----------- > 1 file changed, 13 insertions(+), 11 deletions(-) > > diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c > index 8e1be7ba0103..0b16ada659cc 100644 > --- a/drivers/watchdog/rti_wdt.c > +++ b/drivers/watchdog/rti_wdt.c > @@ -92,7 +92,7 @@ static int rti_wdt_start(struct watchdog_device *wdd) > * to be 50% or less than that; we obviouly want to configure the open > * window as large as possible so we select the 50% option. > */ > - wdd->min_hw_heartbeat_ms = 500 * wdd->timeout; > + wdd->min_hw_heartbeat_ms = 550 * wdd->timeout; > > /* Generate NMI when wdt expires */ > writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL); > @@ -126,31 +126,33 @@ static int rti_wdt_setup_hw_hb(struct watchdog_device *wdd, u32 wsize) > * be petted during the open window; not too early or not too late. > * The HW configuration options only allow for the open window size > * to be 50% or less than that. > + * To avoid any glitches, we accommodate 5% safety margin, with the > + * exception of open window size < 10%. > */ > switch (wsize) { > case RTIWWDSIZE_50P: > - /* 50% open window => 50% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 500 * heartbeat; > + /* 50% open window => 55% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 550 * heartbeat; > break; > > case RTIWWDSIZE_25P: > - /* 25% open window => 75% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 750 * heartbeat; > + /* 25% open window => 80% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 800 * heartbeat; > break; > > case RTIWWDSIZE_12P5: > - /* 12.5% open window => 87.5% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 875 * heartbeat; > + /* 12.5% open window => 92.5% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 925 * heartbeat; > break; > > case RTIWWDSIZE_6P25: > - /* 6.5% open window => 93.5% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 935 * heartbeat; > + /* 6.5% open window => 96.5% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 965 * heartbeat; > break; > > case RTIWWDSIZE_3P125: > - /* 3.125% open window => 96.9% min heartbeat */ > - wdd->min_hw_heartbeat_ms = 969 * heartbeat; > + /* 3.125% open window => 97.9% min heartbeat */ > + wdd->min_hw_heartbeat_ms = 979 * heartbeat; > break; > > default: > -- > 2.43.2 > >
diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c index 8e1be7ba0103..0b16ada659cc 100644 --- a/drivers/watchdog/rti_wdt.c +++ b/drivers/watchdog/rti_wdt.c @@ -92,7 +92,7 @@ static int rti_wdt_start(struct watchdog_device *wdd) * to be 50% or less than that; we obviouly want to configure the open * window as large as possible so we select the 50% option. */ - wdd->min_hw_heartbeat_ms = 500 * wdd->timeout; + wdd->min_hw_heartbeat_ms = 550 * wdd->timeout; /* Generate NMI when wdt expires */ writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL); @@ -126,31 +126,33 @@ static int rti_wdt_setup_hw_hb(struct watchdog_device *wdd, u32 wsize) * be petted during the open window; not too early or not too late. * The HW configuration options only allow for the open window size * to be 50% or less than that. + * To avoid any glitches, we accommodate 5% safety margin, with the + * exception of open window size < 10%. */ switch (wsize) { case RTIWWDSIZE_50P: - /* 50% open window => 50% min heartbeat */ - wdd->min_hw_heartbeat_ms = 500 * heartbeat; + /* 50% open window => 55% min heartbeat */ + wdd->min_hw_heartbeat_ms = 550 * heartbeat; break; case RTIWWDSIZE_25P: - /* 25% open window => 75% min heartbeat */ - wdd->min_hw_heartbeat_ms = 750 * heartbeat; + /* 25% open window => 80% min heartbeat */ + wdd->min_hw_heartbeat_ms = 800 * heartbeat; break; case RTIWWDSIZE_12P5: - /* 12.5% open window => 87.5% min heartbeat */ - wdd->min_hw_heartbeat_ms = 875 * heartbeat; + /* 12.5% open window => 92.5% min heartbeat */ + wdd->min_hw_heartbeat_ms = 925 * heartbeat; break; case RTIWWDSIZE_6P25: - /* 6.5% open window => 93.5% min heartbeat */ - wdd->min_hw_heartbeat_ms = 935 * heartbeat; + /* 6.5% open window => 96.5% min heartbeat */ + wdd->min_hw_heartbeat_ms = 965 * heartbeat; break; case RTIWWDSIZE_3P125: - /* 3.125% open window => 96.9% min heartbeat */ - wdd->min_hw_heartbeat_ms = 969 * heartbeat; + /* 3.125% open window => 97.9% min heartbeat */ + wdd->min_hw_heartbeat_ms = 979 * heartbeat; break; default:
On AM62x, the watchdog is pet before the valid window is open. Fix min_hw_heartbeat and accommodate a 5% safety margin with the exception of open window size < 10%, which shall use <5% due to the smaller open window size. Signed-off-by: Judith Mendez <jm@ti.com> --- drivers/watchdog/rti_wdt.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-)