@@ -76,6 +76,7 @@ struct stmmac_priv {
unsigned int dirty_rx;
unsigned int dma_rx_size;
unsigned int dma_buf_sz;
+ unsigned int rx_copybreak;
u32 rx_riwt;
int hwts_rx_en;
dma_addr_t *rx_skbuff_dma;
@@ -781,6 +781,43 @@ static int stmmac_get_ts_info(struct net_device *dev,
return ethtool_op_get_ts_info(dev, info);
}
+static int stmmac_get_tunable(struct net_device *dev,
+ const struct ethtool_tunable *tuna, void *data)
+{
+ struct stmmac_priv *priv = netdev_priv(dev);
+ int ret = 0;
+
+ switch (tuna->id) {
+ case ETHTOOL_RX_COPYBREAK:
+ *(u32 *)data = priv->rx_copybreak;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static int stmmac_set_tunable(struct net_device *dev,
+ const struct ethtool_tunable *tuna,
+ const void *data)
+{
+ struct stmmac_priv *priv = netdev_priv(dev);
+ int ret = 0;
+
+ switch (tuna->id) {
+ case ETHTOOL_RX_COPYBREAK:
+ priv->rx_copybreak = *(u32 *)data;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
static const struct ethtool_ops stmmac_ethtool_ops = {
.begin = stmmac_check_if_running,
.get_drvinfo = stmmac_ethtool_getdrvinfo,
@@ -803,6 +840,8 @@ static const struct ethtool_ops stmmac_ethtool_ops = {
.get_ts_info = stmmac_get_ts_info,
.get_coalesce = stmmac_get_coalesce,
.set_coalesce = stmmac_set_coalesce,
+ .get_tunable = stmmac_get_tunable,
+ .set_tunable = stmmac_set_tunable,
};
void stmmac_set_ethtool_ops(struct net_device *netdev)
@@ -99,6 +99,8 @@ static int buf_sz = DEFAULT_BUFSIZE;
module_param(buf_sz, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(buf_sz, "DMA buffer size");
+#define STMMAC_RX_COPYBREAK 256
+
static const u32 default_msg_level = (NETIF_MSG_DRV | NETIF_MSG_PROBE |
NETIF_MSG_LINK | NETIF_MSG_IFUP |
NETIF_MSG_IFDOWN | NETIF_MSG_TIMER);
@@ -1842,6 +1844,7 @@ static int stmmac_open(struct net_device *dev)
priv->dma_tx_size = STMMAC_ALIGN(dma_txsize);
priv->dma_rx_size = STMMAC_ALIGN(dma_rxsize);
priv->dma_buf_sz = STMMAC_ALIGN(buf_sz);
+ priv->rx_copybreak = STMMAC_RX_COPYBREAK;
ret = alloc_dma_desc_resources(priv);
if (ret < 0) {
@@ -2195,8 +2198,7 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv)
struct sk_buff *skb;
skb = netdev_alloc_skb_ip_align(priv->dev, bfsize);
-
- if (unlikely(skb == NULL))
+ if (unlikely(!skb))
break;
priv->rx_skbuff[entry] = skb;
@@ -2319,23 +2321,52 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit)
pr_debug("\tframe size %d, COE: %d\n",
frame_len, status);
}
- skb = priv->rx_skbuff[entry];
- if (unlikely(!skb)) {
- pr_err("%s: Inconsistent Rx descriptor chain\n",
- priv->dev->name);
- priv->dev->stats.rx_dropped++;
- break;
+
+ if (unlikely(frame_len < priv->rx_copybreak)) {
+ skb = netdev_alloc_skb_ip_align(priv->dev,
+ frame_len);
+ if (unlikely(!skb)) {
+ if (net_ratelimit())
+ dev_warn(priv->device,
+ "packet dropped\n");
+ priv->dev->stats.rx_dropped++;
+ break;
+ }
+
+ dma_sync_single_for_cpu(priv->device,
+ priv->rx_skbuff_dma
+ [entry], frame_len,
+ DMA_FROM_DEVICE);
+ skb_copy_to_linear_data(skb,
+ priv->
+ rx_skbuff[entry]->data,
+ frame_len);
+
+ skb_put(skb, frame_len);
+ dma_sync_single_for_device(priv->device,
+ priv->rx_skbuff_dma
+ [entry], frame_len,
+ DMA_FROM_DEVICE);
+ } else {
+ skb = priv->rx_skbuff[entry];
+ if (unlikely(!skb)) {
+ pr_err("%s: Inconsistent Rx chain\n",
+ priv->dev->name);
+ priv->dev->stats.rx_dropped++;
+ break;
+ }
+ prefetch(skb->data - NET_IP_ALIGN);
+ priv->rx_skbuff[entry] = NULL;
+
+ skb_put(skb, frame_len);
+ dma_unmap_single(priv->device,
+ priv->rx_skbuff_dma[entry],
+ priv->dma_buf_sz,
+ DMA_FROM_DEVICE);
}
- prefetch(skb->data - NET_IP_ALIGN);
- priv->rx_skbuff[entry] = NULL;
stmmac_get_rx_hwtstamp(priv, entry, skb);
- skb_put(skb, frame_len);
- dma_unmap_single(priv->device,
- priv->rx_skbuff_dma[entry],
- priv->dma_buf_sz, DMA_FROM_DEVICE);
-
if (netif_msg_pktdata(priv)) {
pr_debug("frame received (%dbytes)", frame_len);
print_pkt(skb->data, frame_len);
This patch is to allow this driver to copy tiny frames during the reception process. This is giving more stability while stressing the driver on STi embedded systems. Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com> --- V2: rx_copybreak tunable by using ethtool drivers/net/ethernet/stmicro/stmmac/stmmac.h | 1 + .../net/ethernet/stmicro/stmmac/stmmac_ethtool.c | 39 +++++++++++++ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 61 +++++++++++++++----- 3 files changed, 86 insertions(+), 15 deletions(-)