diff --git a/sys/dev/ath/ath_dfs/null/dfs_null.c b/sys/dev/ath/ath_dfs/null/dfs_null.c
index a3bae914585..e001a4260d5 100644
--- a/sys/dev/ath/ath_dfs/null/dfs_null.c
+++ b/sys/dev/ath/ath_dfs/null/dfs_null.c
@@ -226,3 +226,13 @@ ath_dfs_get_thresholds(struct ath_softc *sc, HAL_PHYERR_PARAM *param)
 	ath_hal_getdfsthresh(sc->sc_ah, param);
 	return 1;
 }
+
+/*
+ * Update the current radar patterns based on the
+ * current operating mode/regulatory domain.
+ */
+int
+ath_dfs_init_radar_filters(struct ath_softc *sc)
+{
+	return 1;
+}
diff --git a/sys/dev/ath/ath_hal/ah.c b/sys/dev/ath/ath_hal/ah.c
index 647f32205bd..2739f97305a 100644
--- a/sys/dev/ath/ath_hal/ah.c
+++ b/sys/dev/ath/ath_hal/ah.c
@@ -522,6 +522,9 @@ ath_hal_getcapability(struct ath_hal *ah, HAL_CAPABILITY_TYPE type,
 	case HAL_CAP_REG_DMN:		/* regulatory domain */
 		*result = AH_PRIVATE(ah)->ah_currentRD;
 		return HAL_OK;
+	case HAL_CAP_DFS_DMN:		/* DFS Domain */
+		*result = AH_PRIVATE(ah)->ah_dfsDomain;
+		return HAL_OK;
 	case HAL_CAP_CIPHER:		/* cipher handled in hardware */
 	case HAL_CAP_TKIP_MIC:		/* handle TKIP MIC in hardware */
 		return HAL_ENOTSUPP;
diff --git a/sys/dev/ath/ath_hal/ah.h b/sys/dev/ath/ath_hal/ah.h
index 0dbb986da90..05ac87d9f43 100644
--- a/sys/dev/ath/ath_hal/ah.h
+++ b/sys/dev/ath/ath_hal/ah.h
@@ -735,6 +735,15 @@ typedef struct {
 #define	HAL_PHYERR_PARAM_NOVAL	65535
 #define	HAL_PHYERR_PARAM_ENABLE	0x8000	/* Enable/Disable if applicable */
 
+/*
+ * DFS operating mode flags.
+ */
+typedef enum {
+	HAL_DFS_UNINIT_DOMAIN	= 0,	/* Uninitialized dfs domain */
+	HAL_DFS_FCC_DOMAIN	= 1,	/* FCC3 dfs domain */
+	HAL_DFS_ETSI_DOMAIN	= 2,	/* ETSI dfs domain */
+	HAL_DFS_MKK4_DOMAIN	= 3,	/* Japan dfs domain */
+} HAL_DFS_DOMAIN;
 
 /*
  * Flag for setting QUIET period
diff --git a/sys/dev/ath/ath_hal/ah_internal.h b/sys/dev/ath/ath_hal/ah_internal.h
index 120620c8751..28c88413f12 100644
--- a/sys/dev/ath/ath_hal/ah_internal.h
+++ b/sys/dev/ath/ath_hal/ah_internal.h
@@ -303,6 +303,7 @@ struct ath_hal_private {
 	 */
 	HAL_REG_DOMAIN	ah_currentRD;		/* EEPROM regulatory domain */
 	HAL_REG_DOMAIN	ah_currentRDext;	/* EEPROM extended regdomain flags */
+	HAL_DFS_DOMAIN	ah_dfsDomain;		/* current DFS domain */
 	HAL_CHANNEL_INTERNAL ah_channels[AH_MAXCHAN]; /* private chan state */
 	u_int		ah_nchan;		/* valid items in ah_channels */
 	const struct regDomain *ah_rd2GHz;	/* reg state for 2G band */
diff --git a/sys/dev/ath/ath_hal/ah_regdomain.c b/sys/dev/ath/ath_hal/ah_regdomain.c
index 43f2b9ba1bd..21bd2c83e80 100644
--- a/sys/dev/ath/ath_hal/ah_regdomain.c
+++ b/sys/dev/ath/ath_hal/ah_regdomain.c
@@ -687,8 +687,9 @@ ath_hal_init_channels(struct ath_hal *ah,
     HAL_BOOL enableExtendedChannels)
 {
 	COUNTRY_CODE_TO_ENUM_RD *country;
-	REG_DOMAIN *rd5GHz, *rd2GHz;
+	REG_DOMAIN *rd5GHz = AH_NULL, *rd2GHz;
 	HAL_STATUS status;
+	HAL_DFS_DOMAIN dfsDomain = HAL_DFS_UNINIT_DOMAIN;
 
 	status = getchannels(ah, chans, maxchans, nchans, modeSelect,
 	    cc, regDmn, enableExtendedChannels, &country, &rd2GHz, &rd5GHz);
@@ -702,6 +703,18 @@ ath_hal_init_channels(struct ath_hal *ah,
 		    __func__, ah->ah_countryCode);
 	} else
 		status = HAL_EINVAL;
+
+	/* Update the DFS setting for the current regulatory domain */
+	if (status == HAL_OK && rd5GHz != AH_NULL) {
+		if (rd5GHz->dfsMask & DFS_FCC3)
+			dfsDomain = HAL_DFS_FCC_DOMAIN;
+		if (rd5GHz->dfsMask & DFS_ETSI)
+			dfsDomain = HAL_DFS_ETSI_DOMAIN;
+		if (rd5GHz->dfsMask & DFS_MKK4)
+			dfsDomain = HAL_DFS_MKK4_DOMAIN;
+	}
+	AH_PRIVATE(ah)->ah_dfsDomain = dfsDomain;
+
 	return status;
 }
 
diff --git a/sys/dev/ath/if_ath.c b/sys/dev/ath/if_ath.c
index 782b790a3a0..1208f1d44db 100644
--- a/sys/dev/ath/if_ath.c
+++ b/sys/dev/ath/if_ath.c
@@ -5031,6 +5031,13 @@ ath_setregdomain(struct ieee80211com *ic, struct ieee80211_regdomain *reg,
 		    __func__, status);
 		return EINVAL;		/* XXX */
 	}
+
+	/*
+	 * Setting country code might change the DFS domain
+	 * so initialize the DFS Radar filters
+	 */
+	ath_dfs_init_radar_filters(sc);
+
 	return 0;
 }
 
diff --git a/sys/dev/ath/if_athdfs.h b/sys/dev/ath/if_athdfs.h
index 88ee7fc7af8..8cc348db37d 100644
--- a/sys/dev/ath/if_athdfs.h
+++ b/sys/dev/ath/if_athdfs.h
@@ -42,6 +42,8 @@ extern	int ath_dfs_process_radar_event(struct ath_softc *sc,
 extern	int ath_dfs_tasklet_needed(struct ath_softc *sc,
     struct ieee80211_channel *chan);
 extern	int ath_ioctl_phyerr(struct ath_softc *sc, struct ath_diag *ad);
-extern	int ath_dfs_get_thresholds(struct ath_softc *sc, HAL_PHYERR_PARAM *param);
+extern	int ath_dfs_get_thresholds(struct ath_softc *sc,
+    HAL_PHYERR_PARAM *param);
+extern	int ath_dfs_init_radar_filters(struct ath_softc *sc);
 
 #endif	/* __IF_ATHDFS_H__ */