i40evf: support ethtool RSS options

Add support for getting and setting RSS hashing options, RSS LUT
entries, and getting the number of device channels from ethtool. Because
the LUT is so small for the VFs, we just read and write the device
registers directly instead of maintaining a shadow copy.

Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40evf/i40evf_ethtool.c

@@ -365,6 +365,316 @@ static int i40evf_set_coalesce(struct net_device *netdev,
 	return 0;
 }
 
+/**
+ * i40e_get_rss_hash_opts - Get RSS hash Input Set for each flow type
+ * @adapter: board private structure
+ * @cmd: ethtool rxnfc command
+ *
+ * Returns Success if the flow is supported, else Invalid Input.
+ **/
+static int i40evf_get_rss_hash_opts(struct i40evf_adapter *adapter,
+				    struct ethtool_rxnfc *cmd)
+{
+	struct i40e_hw *hw = &adapter->hw;
+	u64 hena = (u64)rd32(hw, I40E_VFQF_HENA(0)) |
+		   ((u64)rd32(hw, I40E_VFQF_HENA(1)) << 32);
+
+	/* We always hash on IP src and dest addresses */
+	cmd->data = RXH_IP_SRC | RXH_IP_DST;
+
+	switch (cmd->flow_type) {
+	case TCP_V4_FLOW:
+		if (hena & ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_TCP))
+			cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		break;
+	case UDP_V4_FLOW:
+		if (hena & ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_UDP))
+			cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		break;
+
+	case SCTP_V4_FLOW:
+	case AH_ESP_V4_FLOW:
+	case AH_V4_FLOW:
+	case ESP_V4_FLOW:
+	case IPV4_FLOW:
+		break;
+
+	case TCP_V6_FLOW:
+		if (hena & ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_TCP))
+			cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		break;
+	case UDP_V6_FLOW:
+		if (hena & ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_UDP))
+			cmd->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		break;
+
+	case SCTP_V6_FLOW:
+	case AH_ESP_V6_FLOW:
+	case AH_V6_FLOW:
+	case ESP_V6_FLOW:
+	case IPV6_FLOW:
+		break;
+	default:
+		cmd->data = 0;
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * i40evf_get_rxnfc - command to get RX flow classification rules
+ * @netdev: network interface device structure
+ * @cmd: ethtool rxnfc command
+ *
+ * Returns Success if the command is supported.
+ **/
+static int i40evf_get_rxnfc(struct net_device *netdev,
+			    struct ethtool_rxnfc *cmd,
+			    u32 *rule_locs)
+{
+	struct i40evf_adapter *adapter = netdev_priv(netdev);
+	int ret = -EOPNOTSUPP;
+
+	switch (cmd->cmd) {
+	case ETHTOOL_GRXRINGS:
+		cmd->data = adapter->vsi_res->num_queue_pairs;
+		ret = 0;
+		break;
+	case ETHTOOL_GRXFH:
+		ret = i40evf_get_rss_hash_opts(adapter, cmd);
+		break;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+/**
+ * i40evf_set_rss_hash_opt - Enable/Disable flow types for RSS hash
+ * @adapter: board private structure
+ * @cmd: ethtool rxnfc command
+ *
+ * Returns Success if the flow input set is supported.
+ **/
+static int i40evf_set_rss_hash_opt(struct i40evf_adapter *adapter,
+				   struct ethtool_rxnfc *nfc)
+{
+	struct i40e_hw *hw = &adapter->hw;
+
+	u64 hena = (u64)rd32(hw, I40E_VFQF_HENA(0)) |
+		   ((u64)rd32(hw, I40E_VFQF_HENA(1)) << 32);
+
+	/* RSS does not support anything other than hashing
+	 * to queues on src and dst IPs and ports
+	 */
+	if (nfc->data & ~(RXH_IP_SRC | RXH_IP_DST |
+			  RXH_L4_B_0_1 | RXH_L4_B_2_3))
+		return -EINVAL;
+
+	/* We need at least the IP SRC and DEST fields for hashing */
+	if (!(nfc->data & RXH_IP_SRC) ||
+	    !(nfc->data & RXH_IP_DST))
+		return -EINVAL;
+
+	switch (nfc->flow_type) {
+	case TCP_V4_FLOW:
+		switch (nfc->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
+		case 0:
+			hena &= ~((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_TCP);
+			break;
+		case (RXH_L4_B_0_1 | RXH_L4_B_2_3):
+			hena |= ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_TCP);
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case TCP_V6_FLOW:
+		switch (nfc->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
+		case 0:
+			hena &= ~((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_TCP);
+			break;
+		case (RXH_L4_B_0_1 | RXH_L4_B_2_3):
+			hena |= ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_TCP);
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case UDP_V4_FLOW:
+		switch (nfc->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
+		case 0:
+			hena &= ~(((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_UDP) |
+				  ((u64)1 << I40E_FILTER_PCTYPE_FRAG_IPV4));
+			break;
+		case (RXH_L4_B_0_1 | RXH_L4_B_2_3):
+			hena |= (((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_UDP) |
+				 ((u64)1 << I40E_FILTER_PCTYPE_FRAG_IPV4));
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case UDP_V6_FLOW:
+		switch (nfc->data & (RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
+		case 0:
+			hena &= ~(((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_UDP) |
+				  ((u64)1 << I40E_FILTER_PCTYPE_FRAG_IPV6));
+			break;
+		case (RXH_L4_B_0_1 | RXH_L4_B_2_3):
+			hena |= (((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_UDP) |
+				 ((u64)1 << I40E_FILTER_PCTYPE_FRAG_IPV6));
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case AH_ESP_V4_FLOW:
+	case AH_V4_FLOW:
+	case ESP_V4_FLOW:
+	case SCTP_V4_FLOW:
+		if ((nfc->data & RXH_L4_B_0_1) ||
+		    (nfc->data & RXH_L4_B_2_3))
+			return -EINVAL;
+		hena |= ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_OTHER);
+		break;
+	case AH_ESP_V6_FLOW:
+	case AH_V6_FLOW:
+	case ESP_V6_FLOW:
+	case SCTP_V6_FLOW:
+		if ((nfc->data & RXH_L4_B_0_1) ||
+		    (nfc->data & RXH_L4_B_2_3))
+			return -EINVAL;
+		hena |= ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_OTHER);
+		break;
+	case IPV4_FLOW:
+		hena |= ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV4_OTHER) |
+			((u64)1 << I40E_FILTER_PCTYPE_FRAG_IPV4);
+		break;
+	case IPV6_FLOW:
+		hena |= ((u64)1 << I40E_FILTER_PCTYPE_NONF_IPV6_OTHER) |
+			((u64)1 << I40E_FILTER_PCTYPE_FRAG_IPV6);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	wr32(hw, I40E_VFQF_HENA(0), (u32)hena);
+	wr32(hw, I40E_VFQF_HENA(1), (u32)(hena >> 32));
+	i40e_flush(hw);
+
+	return 0;
+}
+
+/**
+ * i40evf_set_rxnfc - command to set RX flow classification rules
+ * @netdev: network interface device structure
+ * @cmd: ethtool rxnfc command
+ *
+ * Returns Success if the command is supported.
+ **/
+static int i40evf_set_rxnfc(struct net_device *netdev,
+			    struct ethtool_rxnfc *cmd)
+{
+	struct i40evf_adapter *adapter = netdev_priv(netdev);
+	int ret = -EOPNOTSUPP;
+
+	switch (cmd->cmd) {
+	case ETHTOOL_SRXFH:
+		ret = i40evf_set_rss_hash_opt(adapter, cmd);
+		break;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+/**
+ * i40evf_get_channels: get the number of channels supported by the device
+ * @netdev: network interface device structure
+ * @ch: channel information structure
+ *
+ * For the purposes of our device, we only use combined channels, i.e. a tx/rx
+ * queue pair. Report one extra channel to match our "other" MSI-X vector.
+ **/
+static void i40evf_get_channels(struct net_device *netdev,
+				struct ethtool_channels *ch)
+{
+	struct i40evf_adapter *adapter = netdev_priv(netdev);
+
+	/* Report maximum channels */
+	ch->max_combined = adapter->vsi_res->num_queue_pairs;
+
+	ch->max_other = NONQ_VECS;
+	ch->other_count = NONQ_VECS;
+
+	ch->combined_count = adapter->vsi_res->num_queue_pairs;
+}
+
+/**
+ * i40evf_get_rxfh_indir_size - get the rx flow hash indirection table size
+ * @netdev: network interface device structure
+ *
+ * Returns the table size.
+ **/
+static u32 i40evf_get_rxfh_indir_size(struct net_device *netdev)
+{
+	return (I40E_VFQF_HLUT_MAX_INDEX + 1) * 4;
+}
+
+/**
+ * i40evf_get_rxfh_indir - get the rx flow hash indirection table
+ * @netdev: network interface device structure
+ * @indir: indirection table
+ *
+ * Reads the indirection table directly from the hardware. Always returns 0.
+ **/
+static int i40evf_get_rxfh_indir(struct net_device *netdev, u32 *indir)
+{
+	struct i40evf_adapter *adapter = netdev_priv(netdev);
+	struct i40e_hw *hw = &adapter->hw;
+	u32 hlut_val;
+	int i, j;
+
+	for (i = 0, j = 0; i < I40E_VFQF_HLUT_MAX_INDEX; i++) {
+		hlut_val = rd32(hw, I40E_VFQF_HLUT(i));
+		indir[j++] = hlut_val & 0xff;
+		indir[j++] = (hlut_val >> 8) & 0xff;
+		indir[j++] = (hlut_val >> 16) & 0xff;
+		indir[j++] = (hlut_val >> 24) & 0xff;
+	}
+	return 0;
+}
+
+/**
+ * i40evf_set_rxfh_indir - set the rx flow hash indirection table
+ * @netdev: network interface device structure
+ * @indir: indirection table
+ *
+ * Returns -EINVAL if the table specifies an inavlid queue id, otherwise
+ * returns 0 after programming the table.
+ **/
+static int i40evf_set_rxfh_indir(struct net_device *netdev, const u32 *indir)
+{
+	struct i40evf_adapter *adapter = netdev_priv(netdev);
+	struct i40e_hw *hw = &adapter->hw;
+	u32 hlut_val;
+	int i, j;
+
+	for (i = 0, j = 0; i < I40E_VFQF_HLUT_MAX_INDEX + 1; i++) {
+		hlut_val = indir[j++];
+		hlut_val |= indir[j++] << 8;
+		hlut_val |= indir[j++] << 16;
+		hlut_val |= indir[j++] << 24;
+		wr32(hw, I40E_VFQF_HLUT(i), hlut_val);
+	}
+
+	return 0;
+}
+
 static struct ethtool_ops i40evf_ethtool_ops = {
 	.get_settings		= i40evf_get_settings,
 	.get_drvinfo		= i40evf_get_drvinfo,
@@ -378,6 +688,12 @@ static struct ethtool_ops i40evf_ethtool_ops = {
 	.set_msglevel		= i40evf_set_msglevel,
 	.get_coalesce		= i40evf_get_coalesce,
 	.set_coalesce		= i40evf_set_coalesce,
+	.get_rxnfc		= i40evf_get_rxnfc,
+	.set_rxnfc		= i40evf_set_rxnfc,
+	.get_rxfh_indir_size	= i40evf_get_rxfh_indir_size,
+	.get_rxfh_indir		= i40evf_get_rxfh_indir,
+	.set_rxfh_indir		= i40evf_set_rxfh_indir,
+	.get_channels		= i40evf_get_channels,
 };
 
 /**