net: netcp: fix unused interface rx buffer size configuration

Prior to this patch, rx buffer size for each rx queue
of an interface is configurable through dts bindings.
But for an interface, the first rx queue's rx buffer
size is always the usual MTU size (plus usual overhead)
and page size for the remaining rx queues (if they are
enabled by specifying a non-zero rx queue depth dts
binding of the corresponding interface).  This patch
removes the rx buffer size configuration capability.

Signed-off-by: WingMan Kwok <w-kwok2@ti.com>
Acked-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/ti/netcp.h

@@ -85,7 +85,6 @@ struct netcp_intf {
 	struct list_head	rxhook_list_head;
 	unsigned int		rx_queue_id;
 	void			*rx_fdq[KNAV_DMA_FDQ_PER_CHAN];
-	u32			rx_buffer_sizes[KNAV_DMA_FDQ_PER_CHAN];
 	struct napi_struct	rx_napi;
 	struct napi_struct	tx_napi;
 

drivers/net/ethernet/ti/netcp_core.c

@@ -34,6 +34,7 @@
 #define NETCP_SOP_OFFSET	(NET_IP_ALIGN + NET_SKB_PAD)
 #define NETCP_NAPI_WEIGHT	64
 #define NETCP_TX_TIMEOUT	(5 * HZ)
+#define NETCP_PACKET_SIZE	(ETH_FRAME_LEN + ETH_FCS_LEN)
 #define NETCP_MIN_PACKET_SIZE	ETH_ZLEN
 #define NETCP_MAX_MCAST_ADDR	16
 
@@ -804,30 +805,28 @@ static void netcp_allocate_rx_buf(struct netcp_intf *netcp, int fdq)
 	if (likely(fdq == 0)) {
 		unsigned int primary_buf_len;
 		/* Allocate a primary receive queue entry */
-		buf_len = netcp->rx_buffer_sizes[0] + NETCP_SOP_OFFSET;
+		buf_len = NETCP_PACKET_SIZE + NETCP_SOP_OFFSET;
 		primary_buf_len = SKB_DATA_ALIGN(buf_len) +
 				SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 
-		if (primary_buf_len <= PAGE_SIZE) {
-			bufptr = netdev_alloc_frag(primary_buf_len);
-			pad[1] = primary_buf_len;
-		} else {
-			bufptr = kmalloc(primary_buf_len, GFP_ATOMIC |
-					 GFP_DMA32 | __GFP_COLD);
-			pad[1] = 0;
-		}
+		bufptr = netdev_alloc_frag(primary_buf_len);
+		pad[1] = primary_buf_len;
 
 		if (unlikely(!bufptr)) {
-			dev_warn_ratelimited(netcp->ndev_dev, "Primary RX buffer alloc failed\n");
+			dev_warn_ratelimited(netcp->ndev_dev,
+					     "Primary RX buffer alloc failed\n");
 			goto fail;
 		}
 		dma = dma_map_single(netcp->dev, bufptr, buf_len,
 				     DMA_TO_DEVICE);
+		if (unlikely(dma_mapping_error(netcp->dev, dma)))
+			goto fail;
+
 		pad[0] = (u32)bufptr;
 
 	} else {
 		/* Allocate a secondary receive queue entry */
-		page = alloc_page(GFP_ATOMIC | GFP_DMA32 | __GFP_COLD);
+		page = alloc_page(GFP_ATOMIC | GFP_DMA | __GFP_COLD);
 		if (unlikely(!page)) {
 			dev_warn_ratelimited(netcp->ndev_dev, "Secondary page alloc failed\n");
 			goto fail;
@@ -1010,7 +1009,7 @@ netcp_tx_map_skb(struct sk_buff *skb, struct netcp_intf *netcp)
 
 	/* Map the linear buffer */
 	dma_addr = dma_map_single(dev, skb->data, pkt_len, DMA_TO_DEVICE);
-	if (unlikely(!dma_addr)) {
+	if (unlikely(dma_mapping_error(dev, dma_addr))) {
 		dev_err(netcp->ndev_dev, "Failed to map skb buffer\n");
 		return NULL;
 	}
@@ -1546,8 +1545,8 @@ static int netcp_setup_navigator_resources(struct net_device *ndev)
 	knav_queue_disable_notify(netcp->rx_queue);
 
 	/* open Rx FDQs */
-	for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN &&
-	     netcp->rx_queue_depths[i] && netcp->rx_buffer_sizes[i]; ++i) {
+	for (i = 0; i < KNAV_DMA_FDQ_PER_CHAN && netcp->rx_queue_depths[i];
+	     ++i) {
 		snprintf(name, sizeof(name), "rx-fdq-%s-%d", ndev->name, i);
 		netcp->rx_fdq[i] = knav_queue_open(name, KNAV_QUEUE_GP, 0);
 		if (IS_ERR_OR_NULL(netcp->rx_fdq[i])) {
@@ -1941,14 +1940,6 @@ static int netcp_create_interface(struct netcp_device *netcp_device,
 		netcp->rx_queue_depths[0] = 128;
 	}
 
-	ret = of_property_read_u32_array(node_interface, "rx-buffer-size",
-					 netcp->rx_buffer_sizes,
-					 KNAV_DMA_FDQ_PER_CHAN);
-	if (ret) {
-		dev_err(dev, "missing \"rx-buffer-size\" parameter\n");
-		netcp->rx_buffer_sizes[0] = 1536;
-	}
-
 	ret = of_property_read_u32_array(node_interface, "rx-pool", temp, 2);
 	if (ret < 0) {
 		dev_err(dev, "missing \"rx-pool\" parameter\n");