diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c
index daa00f3c5a6a..7f2ca611a3f8 100644
--- a/drivers/watchdog/rti_wdt.c
+++ b/drivers/watchdog/rti_wdt.c
@@ -52,6 +52,8 @@
 
 #define DWDST			BIT(1)
 
+#define MAX_HW_ERROR		250
+
 static int heartbeat = DEFAULT_HEARTBEAT;
 
 /*
@@ -90,7 +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 = 520 * wdd->timeout + MAX_HW_ERROR;
 
 	/* Generate NMI when wdt expires */
 	writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL);
@@ -124,31 +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 2% + max hardware error
+	 * safety margin.
 	 */
 	switch (wsize) {
 	case RTIWWDSIZE_50P:
-		/* 50% open window => 50% min heartbeat */
-		wdd->min_hw_heartbeat_ms = 500 * heartbeat;
+		/* 50% open window => 52% min heartbeat */
+		wdd->min_hw_heartbeat_ms = 520 * heartbeat + MAX_HW_ERROR;
 		break;
 
 	case RTIWWDSIZE_25P:
-		/* 25% open window => 75% min heartbeat */
-		wdd->min_hw_heartbeat_ms = 750 * heartbeat;
+		/* 25% open window => 77% min heartbeat */
+		wdd->min_hw_heartbeat_ms = 770 * heartbeat + MAX_HW_ERROR;
 		break;
 
 	case RTIWWDSIZE_12P5:
-		/* 12.5% open window => 87.5% min heartbeat */
-		wdd->min_hw_heartbeat_ms = 875 * heartbeat;
+		/* 12.5% open window => 89.5% min heartbeat */
+		wdd->min_hw_heartbeat_ms = 895 * heartbeat + MAX_HW_ERROR;
 		break;
 
 	case RTIWWDSIZE_6P25:
-		/* 6.5% open window => 93.5% min heartbeat */
-		wdd->min_hw_heartbeat_ms = 935 * heartbeat;
+		/* 6.5% open window => 95.5% min heartbeat */
+		wdd->min_hw_heartbeat_ms = 955 * heartbeat + MAX_HW_ERROR;
 		break;
 
 	case RTIWWDSIZE_3P125:
-		/* 3.125% open window => 96.9% min heartbeat */
-		wdd->min_hw_heartbeat_ms = 969 * heartbeat;
+		/* 3.125% open window => 98.9% min heartbeat */
+		wdd->min_hw_heartbeat_ms = 989 * heartbeat + MAX_HW_ERROR;
 		break;
 
 	default:
@@ -222,14 +226,6 @@ static int rti_wdt_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	/*
-	 * If watchdog is running at 32k clock, it is not accurate.
-	 * Adjust frequency down in this case so that we don't pet
-	 * the watchdog too often.
-	 */
-	if (wdt->freq < 32768)
-		wdt->freq = wdt->freq * 9 / 10;
-
 	pm_runtime_enable(dev);
 	ret = pm_runtime_get_sync(dev);
 	if (ret < 0) {