qcacld-3.0: Disable PER roam for phymode less than 11NA_HT20

The PER default low rate thresholds configured is 20Mbps. This
will cause PER roam scan always after the 25 secs PER monitor
window since the 11b rates are lower than 20Mbps.

So disable PER roam when the connection/roaming to peer is with
cckm/OFDM rates to avoid frequent roam scans.

Change-Id: Iaae469804547c0f0682b66de3609b5cda4b4b577
CRs-Fixed: 2984973

components/umac/mlme/connection_mgr/core/src/wlan_cm_roam_offload.c

@@ -100,6 +100,45 @@ cm_roam_fill_rssi_change_params(struct wlan_objmgr_psoc *psoc, uint8_t vdev_id,
 	return QDF_STATUS_SUCCESS;
 }
 
+/**
+ * cm_roam_is_per_roam_allowed()  - Check if PER roam trigger needs to be
+ * disabled based on the current connected rates.
+ * @psoc:   Pointer to the psoc object
+ * @vdev_id: Vdev id
+ *
+ * Return: true if PER roam trigger is allowed
+ */
+static bool
+cm_roam_is_per_roam_allowed(struct wlan_objmgr_psoc *psoc, uint8_t vdev_id)
+{
+	struct qdf_mac_addr connected_bssid = {0};
+	struct wlan_objmgr_vdev *vdev;
+	enum wlan_phymode peer_phymode = WLAN_PHYMODE_AUTO;
+	QDF_STATUS status;
+
+	vdev = wlan_objmgr_get_vdev_by_id_from_psoc(psoc, vdev_id,
+						    WLAN_MLME_CM_ID);
+	if (!vdev) {
+		mlme_err("Vdev is null for vdev_id:%d", vdev_id);
+		return false;
+	}
+
+	status = wlan_vdev_get_bss_peer_mac(vdev, &connected_bssid);
+	wlan_objmgr_vdev_release_ref(vdev, WLAN_MLME_CM_ID);
+
+	if (QDF_IS_STATUS_ERROR(status))
+		return false;
+
+	mlme_get_peer_phymode(psoc, connected_bssid.bytes, &peer_phymode);
+	if (peer_phymode < WLAN_PHYMODE_11NA_HT20) {
+		mlme_debug("vdev:%d PER roam trigger disabled for phymode:%d",
+			   peer_phymode, vdev_id);
+		return false;
+	}
+
+	return true;
+}
+
 #ifdef WLAN_FEATURE_ROAM_OFFLOAD
 /**
  * cm_roam_reason_vsie() - set roam reason vsie
@@ -137,9 +176,21 @@ static void
 cm_roam_triggers(struct wlan_objmgr_psoc *psoc, uint8_t vdev_id,
 		 struct wlan_roam_triggers *params)
 {
+	bool is_per_roam_enabled;
+
 	params->vdev_id = vdev_id;
 	params->trigger_bitmap =
 		mlme_get_roam_trigger_bitmap(psoc, vdev_id);
+
+	/*
+	 * Disable PER trigger for phymode less than 11n to avoid
+	 * frequent roams as the PER rate threshold is greater than
+	 * 11a/b/g rates
+	 */
+	is_per_roam_enabled = cm_roam_is_per_roam_allowed(psoc, vdev_id);
+	if (!is_per_roam_enabled)
+		params->trigger_bitmap &= ~BIT(ROAM_TRIGGER_REASON_PER);
+
 	params->roam_scan_scheme_bitmap =
 		wlan_cm_get_roam_scan_scheme_bitmap(psoc, vdev_id);
 	wlan_cm_roam_get_vendor_btm_params(psoc, &params->vendor_btm_param);
@@ -2765,7 +2816,7 @@ cm_roam_fill_per_roam_request(struct wlan_objmgr_psoc *psoc,
 }
 
 /**
- * cm_roam_offload_per_scan() - populates roam offload scan request and sends
+ * cm_roam_offload_per_config() - populates roam offload scan request and sends
  * to fw
  * @psoc: psoc context
  * @vdev_id: vdev id
@@ -2776,8 +2827,18 @@ static QDF_STATUS
 cm_roam_offload_per_config(struct wlan_objmgr_psoc *psoc, uint8_t vdev_id)
 {
 	struct wlan_per_roam_config_req *req;
+	bool is_per_roam_enabled;
 	QDF_STATUS status;
 
+	/*
+	 * Disable PER trigger for phymode less than 11n to avoid
+	 * frequent roams as the PER rate threshold is greater than
+	 * 11a/b/g rates
+	 */
+	is_per_roam_enabled = cm_roam_is_per_roam_allowed(psoc, vdev_id);
+	if (!is_per_roam_enabled)
+		return QDF_STATUS_SUCCESS;
+
 	req = qdf_mem_malloc(sizeof(*req));
 	if (!req)
 		return QDF_STATUS_E_NOMEM;