e1000e: Support RXALL feature flag.

This allows the NIC to receive all frames available, including
those with bad FCS, un-matched vlans, ethernet control frames,
and more.

Tested by sending frames with bad FCS.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/e1000e/defines.h

@@ -177,6 +177,7 @@
 #define E1000_RCTL_VFE            0x00040000    /* vlan filter enable */
 #define E1000_RCTL_CFIEN          0x00080000    /* canonical form enable */
 #define E1000_RCTL_CFI            0x00100000    /* canonical form indicator */
+#define E1000_RCTL_DPF            0x00400000    /* Discard Pause Frames */
 #define E1000_RCTL_PMCF           0x00800000    /* pass MAC control frames */
 #define E1000_RCTL_BSEX           0x02000000    /* Buffer size extension */
 #define E1000_RCTL_SECRC          0x04000000    /* Strip Ethernet CRC */

drivers/net/ethernet/intel/e1000e/netdev.c

@@ -926,7 +926,8 @@ static bool e1000_clean_rx_irq(struct e1000_ring *rx_ring, int *work_done,
 			goto next_desc;
 		}
 
-		if (staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) {
+		if (unlikely((staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) &&
+			     !(netdev->features & NETIF_F_RXALL))) {
 			/* recycle */
 			buffer_info->skb = skb;
 			goto next_desc;
@@ -1255,7 +1256,8 @@ static bool e1000_clean_rx_irq_ps(struct e1000_ring *rx_ring, int *work_done,
 			goto next_desc;
 		}
 
-		if (staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) {
+		if (unlikely((staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) &&
+			     !(netdev->features & NETIF_F_RXALL))) {
 			dev_kfree_skb_irq(skb);
 			goto next_desc;
 		}
@@ -1454,7 +1456,8 @@ static bool e1000_clean_jumbo_rx_irq(struct e1000_ring *rx_ring, int *work_done,
 
 		/* errors is only valid for DD + EOP descriptors */
 		if (unlikely((staterr & E1000_RXD_STAT_EOP) &&
-			     (staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK))) {
+			     ((staterr & E1000_RXDEXT_ERR_FRAME_ERR_MASK) &&
+			      !(netdev->features & NETIF_F_RXALL)))) {
 			/* recycle both page and skb */
 			buffer_info->skb = skb;
 			/* an error means any chain goes out the window too */
@@ -2997,6 +3000,22 @@ static void e1000_setup_rctl(struct e1000_adapter *adapter)
 		ew32(PSRCTL, psrctl);
 	}
 
+	/* This is useful for sniffing bad packets. */
+	if (adapter->netdev->features & NETIF_F_RXALL) {
+		/* UPE and MPE will be handled by normal PROMISC logic
+		 * in e1000e_set_rx_mode */
+		rctl |= (E1000_RCTL_SBP | /* Receive bad packets */
+			 E1000_RCTL_BAM | /* RX All Bcast Pkts */
+			 E1000_RCTL_PMCF); /* RX All MAC Ctrl Pkts */
+
+		rctl &= ~(E1000_RCTL_VFE | /* Disable VLAN filter */
+			  E1000_RCTL_DPF | /* Allow filtered pause */
+			  E1000_RCTL_CFIEN); /* Dis VLAN CFIEN Filter */
+		/* Do not mess with E1000_CTRL_VME, it affects transmit as well,
+		 * and that breaks VLANs.
+		 */
+	}
+
 	ew32(RFCTL, rfctl);
 	ew32(RCTL, rctl);
 	/* just started the receive unit, no need to restart */
@@ -6005,7 +6024,8 @@ static int e1000_set_features(struct net_device *netdev,
 		adapter->flags |= FLAG_TSO_FORCE;
 
 	if (!(changed & (NETIF_F_HW_VLAN_RX | NETIF_F_HW_VLAN_TX |
-			 NETIF_F_RXCSUM | NETIF_F_RXHASH | NETIF_F_RXFCS)))
+			 NETIF_F_RXCSUM | NETIF_F_RXHASH | NETIF_F_RXFCS |
+			 NETIF_F_RXALL)))
 		return 0;
 
 	/*
@@ -6233,6 +6253,7 @@ static int __devinit e1000_probe(struct pci_dev *pdev,
 	netdev->hw_features = netdev->features;
 	netdev->hw_features |= NETIF_F_RXFCS;
 	netdev->priv_flags |= IFF_SUPP_NOFCS;
+	netdev->hw_features |= NETIF_F_RXALL;
 
 	if (adapter->flags & FLAG_HAS_HW_VLAN_FILTER)
 		netdev->features |= NETIF_F_HW_VLAN_FILTER;