drivers: net: xgene: Preparatory patch for TSO support

- Rearranged descriptor writes
- Moved increment command write to xgene_enet_setup_tx_desc

Signed-off-by: Iyappan Subramanian <isubramanian@apm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/apm/xgene/xgene_enet_main.c b/drivers/net/ethernet/apm/xgene/xgene_enet_main.c
index 4f68d19..652b4c3 100644 (file)
--- a/drivers/net/ethernet/apm/xgene/xgene_enet_main.c
+++ b/drivers/net/ethernet/apm/xgene/xgene_enet_main.c
@@ -219,6 +219,11 @@ out:
        return hopinfo;
 }
 
+static u16 xgene_enet_encode_len(u16 len)
+{
+       return (len == BUFLEN_16K) ? 0 : len;
+}
+
 static int xgene_enet_setup_tx_desc(struct xgene_enet_desc_ring *tx_ring,
                                    struct sk_buff *skb)
 {
@@ -227,27 +232,36 @@ static int xgene_enet_setup_tx_desc(struct xgene_enet_desc_ring *tx_ring,
        dma_addr_t dma_addr;
        u16 tail = tx_ring->tail;
        u64 hopinfo;
+       u32 len, hw_len;
+       u8 count = 1;
 
        raw_desc = &tx_ring->raw_desc[tail];
        memset(raw_desc, 0, sizeof(struct xgene_enet_raw_desc));
 
-       dma_addr = dma_map_single(dev, skb->data, skb->len, DMA_TO_DEVICE);
+       len = skb_headlen(skb);
+       hw_len = xgene_enet_encode_len(len);
+
+       dma_addr = dma_map_single(dev, skb->data, len, DMA_TO_DEVICE);
        if (dma_mapping_error(dev, dma_addr)) {
                netdev_err(tx_ring->ndev, "DMA mapping error\n");
                return -EINVAL;
        }
 
        /* Hardware expects descriptor in little endian format */
-       raw_desc->m0 = cpu_to_le64(tail);
        raw_desc->m1 = cpu_to_le64(SET_VAL(DATAADDR, dma_addr) |
-                                  SET_VAL(BUFDATALEN, skb->len) |
+                                  SET_VAL(BUFDATALEN, hw_len) |
                                   SET_BIT(COHERENT));
+
+       raw_desc->m0 = cpu_to_le64(SET_VAL(USERINFO, tail));
        hopinfo = xgene_enet_work_msg(skb);
        raw_desc->m3 = cpu_to_le64(SET_VAL(HENQNUM, tx_ring->dst_ring_num) |
                                   hopinfo);
        tx_ring->cp_ring->cp_skb[tail] = skb;
 
-       return 0;
+       tail = (tail + 1) & (tx_ring->slots - 1);
+       tx_ring->tail = tail;
+
+       return count;
 }
 
 static netdev_tx_t xgene_enet_start_xmit(struct sk_buff *skb,
@@ -257,6 +271,7 @@ static netdev_tx_t xgene_enet_start_xmit(struct sk_buff *skb,
        struct xgene_enet_desc_ring *tx_ring = pdata->tx_ring;
        struct xgene_enet_desc_ring *cp_ring = tx_ring->cp_ring;
        u32 tx_level, cq_level;
+       int count;
 
        tx_level = pdata->ring_ops->len(tx_ring);
        cq_level = pdata->ring_ops->len(cp_ring);
@@ -266,14 +281,14 @@ static netdev_tx_t xgene_enet_start_xmit(struct sk_buff *skb,
                return NETDEV_TX_BUSY;
        }
 
-       if (xgene_enet_setup_tx_desc(tx_ring, skb)) {
+       count = xgene_enet_setup_tx_desc(tx_ring, skb);
+       if (count <= 0) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }
 
-       pdata->ring_ops->wr_cmd(tx_ring, 1);
+       pdata->ring_ops->wr_cmd(tx_ring, count);
        skb_tx_timestamp(skb);
-       tx_ring->tail = (tx_ring->tail + 1) & (tx_ring->slots - 1);
 
        pdata->stats.tx_packets++;
        pdata->stats.tx_bytes += skb->len;

diff --git a/drivers/net/ethernet/apm/xgene/xgene_enet_main.h b/drivers/net/ethernet/apm/xgene/xgene_enet_main.h
index 1c85fc8..2ac547e 100644 (file)
--- a/drivers/net/ethernet/apm/xgene/xgene_enet_main.h
+++ b/drivers/net/ethernet/apm/xgene/xgene_enet_main.h
@@ -40,6 +40,7 @@
 #define XGENE_DRV_VERSION      "v1.0"
 #define XGENE_ENET_MAX_MTU     1536
 #define SKB_BUFFER_SIZE                (XGENE_ENET_MAX_MTU - NET_IP_ALIGN)
+#define BUFLEN_16K     (16 * 1024)
 #define NUM_PKT_BUF    64
 #define NUM_BUFPOOL    32