qcacmn: Set Rx monitor ring fill level to default on monitor soc init

Initially, 2K buffers (default) are allocated and Rx monitor ring fill
level is set to 2K at monitor soc attach and these buffers are used for
enhanced stats.

On monitor vap creation, additional 6K buffers are allocated and monitor
ring fill level is set to 8K.

On execution of wifi command after this, fill level is still set to 8K
and this results in monitor vap to operate with only 2K buffers.

Therefore add functionality to set the fill level to 2K (default) at
monitor soc init instead of monitor soc attach and also add sanity check
for num_req_buffers in the API dp_mon_buffers_replenish.

Change-Id: I0f4b269ab4ed05ed1f0223e3dc83d8675dab4860
CRs-Fixed: 3201411

dp/wifi3.0/monitor/2.0/dp_mon_2.0.c

@@ -244,6 +244,13 @@ dp_mon_buffers_replenish(struct dp_soc *dp_soc,
 	void *mon_srng;
 	QDF_STATUS ret = QDF_STATUS_E_FAILURE;
 
+	if (!num_req_buffers) {
+		dp_mon_debug("%pK: Received request for 0 buffers replenish",
+			     dp_soc);
+		ret = QDF_STATUS_E_INVAL;
+		goto free_desc;
+	}
+
 	mon_srng = dp_mon_srng->hal_srng;
 
 	hal_srng_access_start(dp_soc->hal_soc, mon_srng);
@@ -430,22 +437,27 @@ void dp_vdev_set_monitor_mode_buf_rings_2_0(struct dp_pdev *pdev)
 		return;
 	}
 
-	if (dp_rx_mon_buffers_alloc(soc,
-				    (rx_mon_max_entries - mon_soc_be->rx_mon_ring_fill_level))) {
-		dp_mon_err("%pK: Rx mon buffers allocation failed", soc);
-		return;
-	}
+	if (mon_soc_be->rx_mon_ring_fill_level < rx_mon_max_entries) {
+		if (dp_rx_mon_buffers_alloc(soc,
+					    (rx_mon_max_entries - mon_soc_be->rx_mon_ring_fill_level))) {
+			dp_mon_err("%pK: Rx mon buffers allocation failed", soc);
+			return;
+		}
 
-	if (dp_tx_mon_buffers_alloc(soc,
-				    (tx_mon_max_entries - mon_soc_be->tx_mon_ring_fill_level))) {
-		dp_mon_err("%pK: Tx mon buffers allocation failed", soc);
-		return;
+		mon_soc_be->rx_mon_ring_fill_level +=
+					(rx_mon_max_entries - mon_soc_be->rx_mon_ring_fill_level);
 	}
 
-	mon_soc_be->tx_mon_ring_fill_level +=
-				(tx_mon_max_entries - mon_soc_be->tx_mon_ring_fill_level);
-	mon_soc_be->rx_mon_ring_fill_level +=
-				(rx_mon_max_entries - mon_soc_be->rx_mon_ring_fill_level);
+	if (mon_soc_be->tx_mon_ring_fill_level < tx_mon_max_entries) {
+		if (dp_tx_mon_buffers_alloc(soc,
+					    (tx_mon_max_entries - mon_soc_be->tx_mon_ring_fill_level))) {
+			dp_mon_err("%pK: Tx mon buffers allocation failed", soc);
+			return;
+		}
+
+		mon_soc_be->tx_mon_ring_fill_level +=
+					(tx_mon_max_entries - mon_soc_be->tx_mon_ring_fill_level);
+	}
 }
 
 static
@@ -908,6 +920,9 @@ QDF_STATUS dp_mon_soc_init_2_0(struct dp_soc *soc)
 		goto fail;
 	}
 
+	mon_soc_be->tx_mon_ring_fill_level = DP_MON_RING_FILL_LEVEL_DEFAULT;
+	mon_soc_be->rx_mon_ring_fill_level = DP_MON_RING_FILL_LEVEL_DEFAULT;
+
 	mon_soc_be->is_dp_mon_soc_initialized = true;
 	return QDF_STATUS_SUCCESS;
 fail:
@@ -930,9 +945,6 @@ QDF_STATUS dp_mon_soc_attach_2_0(struct dp_soc *soc)
 		return QDF_STATUS_E_FAILURE;
 	}
 
-	mon_soc_be->tx_mon_ring_fill_level = DP_MON_RING_FILL_LEVEL_DEFAULT;
-	mon_soc_be->rx_mon_ring_fill_level = DP_MON_RING_FILL_LEVEL_DEFAULT;
-
 	entries = wlan_cfg_get_dp_soc_rx_mon_buf_ring_size(soc_cfg_ctx);
 	qdf_print("%s:%d rx mon buf entries: %d", __func__, __LINE__, entries);
 	if (dp_srng_alloc(soc, &soc->rxdma_mon_buf_ring[0],