Title: [7875] trunk/drivers/net/bfin_mac.c: Bug[#5716] handler rx error status in bfin mac driver
- Revision
- 7875
- Author
- sonicz
- Date
- 2009-11-25 05:25:20 -0500 (Wed, 25 Nov 2009)
Log Message
Bug[#5716] handler rx error status in bfin mac driver
Apply patch from Peter Meerwald<[email protected]>
Modified Paths
Diff
Modified: trunk/drivers/net/bfin_mac.c (7874 => 7875)
--- trunk/drivers/net/bfin_mac.c 2009-11-25 07:03:06 UTC (rev 7874)
+++ trunk/drivers/net/bfin_mac.c 2009-11-25 10:25:20 UTC (rev 7875)
@@ -910,6 +910,7 @@
do {
tx_list_head->desc_a.config &= ~DMAEN;
tx_list_head->status.status_word = 0;
+#ifndef CONFIG_BFIN_EXTMEM_WRITEBACK
if (tx_list_head->skb) {
dev_kfree_skb(tx_list_head->skb);
tx_list_head->skb = NULL;
@@ -917,6 +918,7 @@
printk(KERN_ERR DRV_NAME
": no sk_buff in a transmitted frame!\n");
}
+#endif
tx_list_head = tx_list_head->next;
} while (tx_list_head->status.status_word != 0
&& current_tx_ptr != tx_list_head);
@@ -927,13 +929,29 @@
static int bfin_mac_hard_start_xmit(struct sk_buff *skb,
struct net_device *dev)
{
+#ifndef CONFIG_BFIN_EXTMEM_WRITEBACK
u16 *data;
u32 data_align = (unsigned long)(skb->data) & 0x3;
+#endif
union skb_shared_tx *shtx = skb_tx(skb);
if (current_tx_ptr->next == tx_list_head)
return NETDEV_TX_BUSY;
+ /*
+ * Temporary walk around for RX skb buffer corruption issue
+ * when writeback dcache is enabled. Should be removed after
+ * the root cause of this issue is figured out.
+ *
+ * With writeback dcache option, if TX skb is not freed until
+ * its DMA is done and until this xmit function is called for
+ * next TX skb, RX skb buffer may be corrupted after RX DMA is
+ * done. If free TX skb immediately before xmit exits, this issue
+ * disappears. This walk around takes effect at the cost of
+ * copying each tx skb buffer to tx ring other than 4-byte
+ * aligned ones only.
+ */
+#ifndef CONFIG_BFIN_EXTMEM_WRITEBACK
current_tx_ptr->skb = skb;
if (data_align == 0x2) {
@@ -954,6 +972,7 @@
blackfin_dcache_flush_range((u32)data,
(u32)((u8 *)data + skb->len + 4));
} else {
+#endif
*((u16 *)(current_tx_ptr->packet)) = (u16)(skb->len);
/* enable timestamping for the sent packet */
if (shtx->hardware)
@@ -967,7 +986,9 @@
blackfin_dcache_flush_range(
(u32)current_tx_ptr->packet,
(u32)(current_tx_ptr->packet + skb->len + 2));
+#ifndef CONFIG_BFIN_EXTMEM_WRITEBACK
}
+#endif
/* make sure the internal data buffers in the core are drained
* so that the DMA descriptors are completely written when the
@@ -994,14 +1015,20 @@
bfin_tx_hwtstamp(dev, skb);
- current_tx_ptr = current_tx_ptr->next;
dev->trans_start = jiffies;
dev->stats.tx_packets++;
dev->stats.tx_bytes += (skb->len);
+#ifdef CONFIG_BFIN_EXTMEM_WRITEBACK
+ dev_kfree_skb(skb);
+#endif
+ current_tx_ptr = current_tx_ptr->next;
+
return NETDEV_TX_OK;
}
#define ETH_FCS_LENGTH 4
+#define RX_ERROR_MASK (RX_LONG | RX_ALIGN | RX_CRC | RX_LEN | \
+ RX_FRAG | RX_ADDR | RX_DMAO | RX_PHY | RX_LATE | RX_RANGE)
static void bfin_mac_rx(struct net_device *dev)
{
@@ -1012,6 +1039,15 @@
unsigned int i;
unsigned char fcs[ETH_FCS_LENGTH + 1];
#endif
+ /* check if frame status word reports an error condition
+ * we which case we simply drop the packet
+ */
+ if (current_rx_ptr->status.status_word & RX_ERROR_MASK) {
+ printk(KERN_NOTICE DRV_NAME
+ ": rx: receive error - packet dropped\n");
+ dev->stats.rx_dropped++;
+ goto out;
+ }
/* allocate a new skb for next time receive */
skb = current_rx_ptr->skb;
@@ -1068,10 +1104,10 @@
netif_rx(skb);
dev->stats.rx_packets++;
dev->stats.rx_bytes += len;
+out:
current_rx_ptr->status.status_word = 0x00000000;
current_rx_ptr = current_rx_ptr->next;
-out:
return;
}
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