From 96dab9f2b766328c30fa52fb9a22bc6a317310e3 Mon Sep 17 00:00:00 2001 From: Judith Mendez Date: Wed, 3 Apr 2024 16:24:26 -0500 Subject: watchdog: rti_wdt: Set min_hw_heartbeat_ms to accommodate 5% safety margin 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. Upstream-Status: Submitted [https://lore.kernel.org/all/20240403212426.582727-1-jm@ti.com/] Signed-off-by: Judith Mendez --- 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 3bdc7bfb7c75..859ef121886d 100644 --- a/drivers/watchdog/rti_wdt.c +++ b/drivers/watchdog/rti_wdt.c @@ -90,7 +90,7 @@ 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); @@ -124,31 +124,33 @@ 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: -- cgit v1.2.3