enetc: Add RFS and RSS support

A ternary match table is used for RFS. If multiple entries in the table
match, the entry with the lowest numerical values index is chosen as the
matching entry.  Entries in the table are identified using an index
which takes a value from 0 to PRFSCAPR[NUM_RFS]-1 when accessed by the
PSI (PF).
Portions of the RFS table can be assigned to each SI by the PSI (PF)
driver in PSIaRFSCFGR.  Assignments are cumulative, the entries assigned
to SIn start after those assigned to SIn-1.  The total assignments to
all SIs must be equal to or less than the number available to the port
as found in PRFSCAPR.

For RSS, the Toeplitz hash function used requires two inputs, a 40B
random secret key that is supplied through the PRSSKR0-9 registers as well
as the relevant pieces of the packet header (n-tuple).  The 6 LSB bits of
the hash function result will then be used as a pointer to obtain the tag
referenced in the 64 entry indirection table.  The result will provide a
winning group which will be used to help route the received packet.

Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 77 insertions, 0 deletions

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index f63be02cffae..37b587c541ee 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -638,6 +638,7 @@ static int enetc_clean_rx_ring(struct enetc_bdr *rx_ring,
 }
 
 /* Probing and Init */
+#define ENETC_MAX_RFS_SIZE 64
 void enetc_get_si_caps(struct enetc_si *si)
 {
 	struct enetc_hw *hw = &si->hw;
@@ -647,6 +648,17 @@ void enetc_get_si_caps(struct enetc_si *si)
 	val = enetc_rd(hw, ENETC_SICAPR0);
 	si->num_rx_rings = (val >> 16) & 0xff;
 	si->num_tx_rings = val & 0xff;
+
+	val = enetc_rd(hw, ENETC_SIRFSCAPR);
+	si->num_fs_entries = ENETC_SIRFSCAPR_GET_NUM_RFS(val);
+	si->num_fs_entries = min(si->num_fs_entries, ENETC_MAX_RFS_SIZE);
+
+	si->num_rss = 0;
+	val = enetc_rd(hw, ENETC_SIPCAPR0);
+	if (val & ENETC_SIPCAPR0_RSS) {
+		val = enetc_rd(hw, ENETC_SIRSSCAPR);
+		si->num_rss = ENETC_SIRSSCAPR_GET_NUM_RSS(val);
+	}
 }
 
 static int enetc_dma_alloc_bdr(struct enetc_bdr *r, size_t bd_size)
@@ -898,10 +910,31 @@ static void enetc_clear_cbdr(struct enetc_hw *hw)
 	enetc_wr(hw, ENETC_SICBDRMR, 0);
 }
 
+static int enetc_setup_default_rss_table(struct enetc_si *si, int num_groups)
+{
+	int *rss_table;
+	int i;
+
+	rss_table = kmalloc_array(si->num_rss, sizeof(*rss_table), GFP_KERNEL);
+	if (!rss_table)
+		return -ENOMEM;
+
+	/* Set up RSS table defaults */
+	for (i = 0; i < si->num_rss; i++)
+		rss_table[i] = i % num_groups;
+
+	enetc_set_rss_table(si, rss_table, si->num_rss);
+
+	kfree(rss_table);
+
+	return 0;
+}
+
 static int enetc_configure_si(struct enetc_ndev_priv *priv)
 {
 	struct enetc_si *si = priv->si;
 	struct enetc_hw *hw = &si->hw;
+	int err;
 
 	enetc_setup_cbdr(hw, &si->cbd_ring);
 	/* set SI cache attributes */
@@ -911,6 +944,12 @@ static int enetc_configure_si(struct enetc_ndev_priv *priv)
 	/* enable SI */
 	enetc_wr(hw, ENETC_SIMR, ENETC_SIMR_EN);
 
+	if (si->num_rss) {
+		err = enetc_setup_default_rss_table(si, priv->num_rx_rings);
+		if (err)
+			return err;
+	}
+
 	return 0;
 }
 
@@ -943,6 +982,13 @@ int enetc_alloc_si_resources(struct enetc_ndev_priv *priv)
 	if (err)
 		return err;
 
+	priv->cls_rules = kcalloc(si->num_fs_entries, sizeof(*priv->cls_rules),
+				  GFP_KERNEL);
+	if (!priv->cls_rules) {
+		err = -ENOMEM;
+		goto err_alloc_cls;
+	}
+
 	err = enetc_configure_si(priv);
 	if (err)
 		goto err_config_si;
@@ -950,6 +996,8 @@ int enetc_alloc_si_resources(struct enetc_ndev_priv *priv)
 	return 0;
 
 err_config_si:
+	kfree(priv->cls_rules);
+err_alloc_cls:
 	enetc_clear_cbdr(&si->hw);
 	enetc_free_cbdr(priv->dev, &si->cbd_ring);
 
@@ -962,6 +1010,8 @@ void enetc_free_si_resources(struct enetc_ndev_priv *priv)
 
 	enetc_clear_cbdr(&si->hw);
 	enetc_free_cbdr(priv->dev, &si->cbd_ring);
+
+	kfree(priv->cls_rules);
 }
 
 static void enetc_setup_txbdr(struct enetc_hw *hw, struct enetc_bdr *tx_ring)
@@ -1316,6 +1366,33 @@ struct net_device_stats *enetc_get_stats(struct net_device *ndev)
 	return stats;
 }
 
+static int enetc_set_rss(struct net_device *ndev, int en)
+{
+	struct enetc_ndev_priv *priv = netdev_priv(ndev);
+	struct enetc_hw *hw = &priv->si->hw;
+	u32 reg;
+
+	enetc_wr(hw, ENETC_SIRBGCR, priv->num_rx_rings);
+
+	reg = enetc_rd(hw, ENETC_SIMR);
+	reg &= ~ENETC_SIMR_RSSE;
+	reg |= (en) ? ENETC_SIMR_RSSE : 0;
+	enetc_wr(hw, ENETC_SIMR, reg);
+
+	return 0;
+}
+
+int enetc_set_features(struct net_device *ndev,
+		       netdev_features_t features)
+{
+	netdev_features_t changed = ndev->features ^ features;
+
+	if (changed & NETIF_F_RXHASH)
+		enetc_set_rss(ndev, !!(features & NETIF_F_RXHASH));
+
+	return 0;
+}
+
 int enetc_alloc_msix(struct enetc_ndev_priv *priv)
 {
 	struct pci_dev *pdev = priv->si->pdev;