ixgbe: Enable Jumbo Frames on the X540 10Gigabit Controller

The X540 controller supports jumbo frames in SR-IOV mode.  Allow
configuration of jumbo frames either in the PF driver or on behalf of
a VF.

Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 28 insertions, 1 deletions

diff --git a/drivers/net/ixgbe/ixgbe_sriov.c b/drivers/net/ixgbe/ixgbe_sriov.c
index 187b3a16ec1f..fb4868d0a32d 100644
--- a/drivers/net/ixgbe/ixgbe_sriov.c
+++ b/drivers/net/ixgbe/ixgbe_sriov.c
@@ -110,6 +110,33 @@ static int ixgbe_set_vf_vlan(struct ixgbe_adapter *adapter, int add, int vid,
         return adapter->hw.mac.ops.set_vfta(&adapter->hw, vid, vf, (bool)add);
 }
 
+void ixgbe_set_vf_lpe(struct ixgbe_adapter *adapter, u32 *msgbuf)
+{
+        struct ixgbe_hw *hw = &adapter->hw;
+        int new_mtu = msgbuf[1];
+        u32 max_frs;
+        int max_frame = new_mtu + ETH_HLEN + ETH_FCS_LEN;
+
+        /* Only X540 supports jumbo frames in IOV mode */
+        if (adapter->hw.mac.type != ixgbe_mac_X540)
+                return;
+
+        /* MTU < 68 is an error and causes problems on some kernels */
+        if ((new_mtu < 68) || (max_frame > IXGBE_MAX_JUMBO_FRAME_SIZE)) {
+                e_err(drv, "VF mtu %d out of range\n", new_mtu);
+                return;
+        }
+
+        max_frs = (IXGBE_READ_REG(hw, IXGBE_MAXFRS) &
+                   IXGBE_MHADD_MFS_MASK) >> IXGBE_MHADD_MFS_SHIFT;
+        if (max_frs < new_mtu) {
+                max_frs = new_mtu << IXGBE_MHADD_MFS_SHIFT;
+                IXGBE_WRITE_REG(hw, IXGBE_MAXFRS, max_frs);
+        }
+
+        e_info(hw, "VF requests change max MTU to %d\n", new_mtu);
+}
+
 static void ixgbe_set_vmolr(struct ixgbe_hw *hw, u32 vf, bool aupe)
 {
         u32 vmolr = IXGBE_READ_REG(hw, IXGBE_VMOLR(vf));
@@ -302,7 +329,7 @@ static int ixgbe_rcv_msg_from_vf(struct ixgbe_adapter *adapter, u32 vf)
                                                  hash_list, vf);
                 break;
         case IXGBE_VF_SET_LPE:
-                WARN_ON((msgbuf[0] & 0xFFFF) == IXGBE_VF_SET_LPE);
+                ixgbe_set_vf_lpe(adapter, msgbuf);
                 break;
         case IXGBE_VF_SET_VLAN:
                 add = (msgbuf[0] & IXGBE_VT_MSGINFO_MASK)