ice: Implement ethtool hook for RSS switch

This patch implements ethtool hook for enabling/disabling
RSS. While disabling RSS, the LUT should be cleared. And
the LUT should be reconfigured while enabling RSS.

Signed-off-by: Md Fahad Iqbal Polash <md.fahad.iqbal.polash@intel.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

3 files changed, 40 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index 8f7ee77cb70b..98e8b7096e47 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -1223,6 +1223,38 @@ static void ice_vsi_map_rings_to_vectors(struct ice_vsi *vsi)
 }
 
 /**
+ * ice_vsi_manage_rss_lut - disable/enable RSS
+ * @vsi: the VSI being changed
+ * @ena: boolean value indicating if this is an enable or disable request
+ *
+ * In the event of disable request for RSS, this function will zero out RSS
+ * LUT, while in the event of enable request for RSS, it will reconfigure RSS
+ * LUT.
+ */
+int ice_vsi_manage_rss_lut(struct ice_vsi *vsi, bool ena)
+{
+        int err = 0;
+        u8 *lut;
+
+        lut = devm_kzalloc(&vsi->back->pdev->dev, vsi->rss_table_size,
+                           GFP_KERNEL);
+        if (!lut)
+                return -ENOMEM;
+
+        if (ena) {
+                if (vsi->rss_lut_user)
+                        memcpy(lut, vsi->rss_lut_user, vsi->rss_table_size);
+                else
+                        ice_fill_rss_lut(lut, vsi->rss_table_size,
+                                         vsi->rss_size);
+        }
+
+        err = ice_set_rss(vsi, NULL, lut, vsi->rss_table_size);
+        devm_kfree(&vsi->back->pdev->dev, lut);
+        return err;
+}
+
+/**
  * ice_vsi_cfg_rss_lut_key - Configure RSS params for a VSI
  * @vsi: VSI to be configured
  */
diff --git a/drivers/net/ethernet/intel/ice/ice_lib.h b/drivers/net/ethernet/intel/ice/ice_lib.h
index 4265464ee3d3..2617afe01c82 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.h
+++ b/drivers/net/ethernet/intel/ice/ice_lib.h
@@ -70,5 +70,7 @@ void ice_vsi_free_tx_rings(struct ice_vsi *vsi);
 
 int ice_vsi_cfg_tc(struct ice_vsi *vsi, u8 ena_tc);
 
+int ice_vsi_manage_rss_lut(struct ice_vsi *vsi, bool ena);
+
 irqreturn_t ice_msix_clean_rings(int __always_unused irq, void *data);
 #endif /* !_ICE_LIB_H_ */
diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index d9f30d15ad65..bb76a0bf2fd1 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -2412,6 +2412,12 @@ static int ice_set_features(struct net_device *netdev,
         struct ice_vsi *vsi = np->vsi;
         int ret = 0;
 
+        if (features & NETIF_F_RXHASH && !(netdev->features & NETIF_F_RXHASH))
+                ret = ice_vsi_manage_rss_lut(vsi, true);
+        else if (!(features & NETIF_F_RXHASH) &&
+                 netdev->features & NETIF_F_RXHASH)
+                ret = ice_vsi_manage_rss_lut(vsi, false);
+
         if ((features & NETIF_F_HW_VLAN_CTAG_RX) &&
             !(netdev->features & NETIF_F_HW_VLAN_CTAG_RX))
                 ret = ice_vsi_manage_vlan_stripping(vsi, true);