7 files changed, 190 insertions, 38 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
index b816a624a6ce..fa079bbab89a 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_82598.c
@@ -358,7 +358,6 @@ static s32 ixgbe_fc_enable_82598(struct ixgbe_hw *hw, s32 packetbuf_num)
         u32 fctrl_reg;
         u32 rmcs_reg;
         u32 reg;
-        u32 rx_pba_size;
         u32 link_speed = 0;
         bool link_up;
 
@@ -461,16 +460,13 @@ static s32 ixgbe_fc_enable_82598(struct ixgbe_hw *hw, s32 packetbuf_num)
 
         /* Set up and enable Rx high/low water mark thresholds, enable XON. */
         if (hw->fc.current_mode & ixgbe_fc_tx_pause) {
-                rx_pba_size = IXGBE_READ_REG(hw, IXGBE_RXPBSIZE(packetbuf_num));
-                rx_pba_size >>= IXGBE_RXPBSIZE_SHIFT;
-
-                reg = (rx_pba_size - hw->fc.low_water) << 6;
+                reg = hw->fc.low_water << 6;
                 if (hw->fc.send_xon)
                         reg |= IXGBE_FCRTL_XONE;
 
                 IXGBE_WRITE_REG(hw, IXGBE_FCRTL(packetbuf_num), reg);
 
-                reg = (rx_pba_size - hw->fc.high_water) << 6;
+                reg = hw->fc.high_water[packetbuf_num] << 6;
                 reg |= IXGBE_FCRTH_FCEN;
 
                 IXGBE_WRITE_REG(hw, IXGBE_FCRTH(packetbuf_num), reg);
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
index 84ed9ef7288d..59cd54cfdc1f 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_common.c
@@ -1932,7 +1932,6 @@ s32 ixgbe_fc_enable_generic(struct ixgbe_hw *hw, s32 packetbuf_num)
         s32 ret_val = 0;
         u32 mflcn_reg, fccfg_reg;
         u32 reg;
-        u32 rx_pba_size;
         u32 fcrtl, fcrth;
 
 #ifdef CONFIG_DCB
@@ -2012,11 +2011,8 @@ s32 ixgbe_fc_enable_generic(struct ixgbe_hw *hw, s32 packetbuf_num)
         IXGBE_WRITE_REG(hw, IXGBE_MFLCN, mflcn_reg);
         IXGBE_WRITE_REG(hw, IXGBE_FCCFG, fccfg_reg);
 
-        rx_pba_size = IXGBE_READ_REG(hw, IXGBE_RXPBSIZE(packetbuf_num));
-        rx_pba_size >>= IXGBE_RXPBSIZE_SHIFT;
-
-        fcrth = (rx_pba_size - hw->fc.high_water) << 10;
-        fcrtl = (rx_pba_size - hw->fc.low_water) << 10;
+        fcrth = hw->fc.high_water[packetbuf_num] << 10;
+        fcrtl = hw->fc.low_water << 10;
 
         if (hw->fc.current_mode & ixgbe_fc_tx_pause) {
                 fcrth |= IXGBE_FCRTH_FCEN;
@@ -2293,7 +2289,9 @@ static s32 ixgbe_setup_fc(struct ixgbe_hw *hw, s32 packetbuf_num)
          * Validate the water mark configuration.  Zero water marks are invalid
          * because it causes the controller to just blast out fc packets.
          */
-        if (!hw->fc.low_water || !hw->fc.high_water || !hw->fc.pause_time) {
+        if (!hw->fc.low_water ||
+            !hw->fc.high_water[packetbuf_num] ||
+            !hw->fc.pause_time) {
                 hw_dbg(hw, "Invalid water mark configuration\n");
                 ret_val = IXGBE_ERR_INVALID_LINK_SETTINGS;
                 goto out;
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb.h
index 0a68aa7f5d18..df095a9bbe2b 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb.h
@@ -36,7 +36,6 @@
 
 #define IXGBE_MAX_PACKET_BUFFERS 8
 #define MAX_USER_PRIORITY        8
-#define MAX_TRAFFIC_CLASS        8
 #define MAX_BW_GROUP             8
 #define BW_PERCENT               100
 
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82598.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82598.c
index 2288c3cac010..fcd0e479721f 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82598.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82598.c
@@ -191,7 +191,7 @@ s32 ixgbe_dcb_config_tx_data_arbiter_82598(struct ixgbe_hw *hw,
  */
 s32 ixgbe_dcb_config_pfc_82598(struct ixgbe_hw *hw, u8 pfc_en)
 {
-        u32 reg, rx_pba_size;
+        u32 reg;
         u8  i;
 
         if (pfc_en) {
@@ -222,9 +222,8 @@ s32 ixgbe_dcb_config_pfc_82598(struct ixgbe_hw *hw, u8 pfc_en)
          */
         for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
                 int enabled = pfc_en & (1 << i);
-                rx_pba_size = IXGBE_READ_REG(hw, IXGBE_RXPBSIZE(i));
-                rx_pba_size >>= IXGBE_RXPBSIZE_SHIFT;
-                reg = (rx_pba_size - hw->fc.low_water) << 10;
+
+                reg = hw->fc.low_water << 10;
 
                 if (enabled == pfc_enabled_tx ||
                     enabled == pfc_enabled_full)
@@ -232,7 +231,7 @@ s32 ixgbe_dcb_config_pfc_82598(struct ixgbe_hw *hw, u8 pfc_en)
 
                 IXGBE_WRITE_REG(hw, IXGBE_FCRTL(i), reg);
 
-                reg = (rx_pba_size - hw->fc.high_water) << 10;
+                reg = hw->fc.high_water[i] << 10;
                 if (enabled == pfc_enabled_tx ||
                     enabled == pfc_enabled_full)
                         reg |= IXGBE_FCRTH_FCEN;
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82599.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82599.c
index d64fb872978e..02f6724bf48e 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82599.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_dcb_82599.c
@@ -210,21 +210,19 @@ s32 ixgbe_dcb_config_tx_data_arbiter_82599(struct ixgbe_hw *hw,
  */
 s32 ixgbe_dcb_config_pfc_82599(struct ixgbe_hw *hw, u8 pfc_en)
 {
-        u32 i, reg, rx_pba_size;
+        u32 i, reg;
 
         /* Configure PFC Tx thresholds per TC */
         for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
                 int enabled = pfc_en & (1 << i);
-                rx_pba_size = IXGBE_READ_REG(hw, IXGBE_RXPBSIZE(i));
-                rx_pba_size >>= IXGBE_RXPBSIZE_SHIFT;
 
-                reg = (rx_pba_size - hw->fc.low_water) << 10;
+                reg = hw->fc.low_water << 10;
 
                 if (enabled)
                         reg |= IXGBE_FCRTL_XONE;
                 IXGBE_WRITE_REG(hw, IXGBE_FCRTL_82599(i), reg);
 
-                reg = (rx_pba_size - hw->fc.high_water) << 10;
+                reg = hw->fc.high_water[i] << 10;
                 if (enabled)
                         reg |= IXGBE_FCRTH_FCEN;
                 IXGBE_WRITE_REG(hw, IXGBE_FCRTH_82599(i), reg);
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 3594b09f4993..ba703d30f3a9 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -3351,9 +3351,128 @@ static void ixgbe_configure_dcb(struct ixgbe_adapter *adapter)
                 IXGBE_WRITE_REG(hw, IXGBE_RQTC, reg);
         }
 }
+#endif
+
+/* Additional bittime to account for IXGBE framing */
+#define IXGBE_ETH_FRAMING 20
+
+/*
+ * ixgbe_hpbthresh - calculate high water mark for flow control
+ *
+ * @adapter: board private structure to calculate for
+ * @pb - packet buffer to calculate
+ */
+static int ixgbe_hpbthresh(struct ixgbe_adapter *adapter, int pb)
+{
+        struct ixgbe_hw *hw = &adapter->hw;
+        struct net_device *dev = adapter->netdev;
+        int link, tc, kb, marker;
+        u32 dv_id, rx_pba;
+
+        /* Calculate max LAN frame size */
+        tc = link = dev->mtu + ETH_HLEN + ETH_FCS_LEN + IXGBE_ETH_FRAMING;
+
+#ifdef IXGBE_FCOE
+        /* FCoE traffic class uses FCOE jumbo frames */
+        if (dev->features & NETIF_F_FCOE_MTU) {
+                int fcoe_pb = 0;
 
+#ifdef CONFIG_IXGBE_DCB
+                fcoe_pb = netdev_get_prio_tc_map(dev, adapter->fcoe.up);
+
+#endif
+                if (fcoe_pb == pb && tc < IXGBE_FCOE_JUMBO_FRAME_SIZE)
+                        tc = IXGBE_FCOE_JUMBO_FRAME_SIZE;
+        }
 #endif
 
+        /* Calculate delay value for device */
+        switch (hw->mac.type) {
+        case ixgbe_mac_X540:
+                dv_id = IXGBE_DV_X540(link, tc);
+                break;
+        default:
+                dv_id = IXGBE_DV(link, tc);
+                break;
+        }
+
+        /* Loopback switch introduces additional latency */
+        if (adapter->flags & IXGBE_FLAG_SRIOV_ENABLED)
+                dv_id += IXGBE_B2BT(tc);
+
+        /* Delay value is calculated in bit times convert to KB */
+        kb = IXGBE_BT2KB(dv_id);
+        rx_pba = IXGBE_READ_REG(hw, IXGBE_RXPBSIZE(pb)) >> 10;
+
+        marker = rx_pba - kb;
+
+        /* It is possible that the packet buffer is not large enough
+         * to provide required headroom. In this case throw an error
+         * to user and a do the best we can.
+         */
+        if (marker < 0) {
+                e_warn(drv, "Packet Buffer(%i) can not provide enough"
+                            "headroom to support flow control."
+                            "Decrease MTU or number of traffic classes\n", pb);
+                marker = tc + 1;
+        }
+
+        return marker;
+}
+
+/*
+ * ixgbe_lpbthresh - calculate low water mark for for flow control
+ *
+ * @adapter: board private structure to calculate for
+ * @pb - packet buffer to calculate
+ */
+static int ixgbe_lpbthresh(struct ixgbe_adapter *adapter)
+{
+        struct ixgbe_hw *hw = &adapter->hw;
+        struct net_device *dev = adapter->netdev;
+        int tc;
+        u32 dv_id;
+
+        /* Calculate max LAN frame size */
+        tc = dev->mtu + ETH_HLEN + ETH_FCS_LEN;
+
+        /* Calculate delay value for device */
+        switch (hw->mac.type) {
+        case ixgbe_mac_X540:
+                dv_id = IXGBE_LOW_DV_X540(tc);
+                break;
+        default:
+                dv_id = IXGBE_LOW_DV(tc);
+                break;
+        }
+
+        /* Delay value is calculated in bit times convert to KB */
+        return IXGBE_BT2KB(dv_id);
+}
+
+/*
+ * ixgbe_pbthresh_setup - calculate and setup high low water marks
+ */
+static void ixgbe_pbthresh_setup(struct ixgbe_adapter *adapter)
+{
+        struct ixgbe_hw *hw = &adapter->hw;
+        int num_tc = netdev_get_num_tc(adapter->netdev);
+        int i;
+
+        if (!num_tc)
+                num_tc = 1;
+
+        hw->fc.low_water = ixgbe_lpbthresh(adapter);
+
+        for (i = 0; i < num_tc; i++) {
+                hw->fc.high_water[i] = ixgbe_hpbthresh(adapter, i);
+
+                /* Low water marks must not be larger than high water marks */
+                if (hw->fc.low_water > hw->fc.high_water[i])
+                        hw->fc.low_water = 0;
+        }
+}
+
 static void ixgbe_configure_pb(struct ixgbe_adapter *adapter)
 {
         struct ixgbe_hw *hw = &adapter->hw;
@@ -3367,6 +3486,7 @@ static void ixgbe_configure_pb(struct ixgbe_adapter *adapter)
                 hdrm = 0;
 
         hw->mac.ops.set_rxpba(hw, tc, hdrm, PBA_STRATEGY_EQUAL);
+        ixgbe_pbthresh_setup(adapter);
 }
 
 static void ixgbe_fdir_filter_restore(struct ixgbe_adapter *adapter)
@@ -4769,13 +4889,11 @@ static int __devinit ixgbe_sw_init(struct ixgbe_adapter *adapter)
 {
         struct ixgbe_hw *hw = &adapter->hw;
         struct pci_dev *pdev = adapter->pdev;
-        struct net_device *dev = adapter->netdev;
         unsigned int rss;
 #ifdef CONFIG_IXGBE_DCB
         int j;
         struct tc_configuration *tc;
 #endif
-        int max_frame = dev->mtu + ETH_HLEN + ETH_FCS_LEN;
 
         /* PCI config space info */
 
@@ -4851,8 +4969,7 @@ static int __devinit ixgbe_sw_init(struct ixgbe_adapter *adapter)
 #ifdef CONFIG_DCB
         adapter->last_lfc_mode = hw->fc.current_mode;
 #endif
-        hw->fc.high_water = FC_HIGH_WATER(max_frame);
-        hw->fc.low_water = FC_LOW_WATER(max_frame);
+        ixgbe_pbthresh_setup(adapter);
         hw->fc.pause_time = IXGBE_DEFAULT_FCPAUSE;
         hw->fc.send_xon = true;
         hw->fc.disable_fc_autoneg = false;
@@ -5119,9 +5236,6 @@ static int ixgbe_change_mtu(struct net_device *netdev, int new_mtu)
         /* must set new MTU before calling down or up */
         netdev->mtu = new_mtu;
 
-        hw->fc.high_water = FC_HIGH_WATER(max_frame);
-        hw->fc.low_water = FC_LOW_WATER(max_frame);
-
         if (netif_running(netdev))
                 ixgbe_reinit_locked(adapter);
 
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
index 9a03341e5261..16dd461d4af3 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_type.h
@@ -404,6 +404,7 @@
 #define IXGBE_WUPL_LENGTH_MASK 0xFFFF
 
 /* DCB registers */
+#define MAX_TRAFFIC_CLASS        8
 #define IXGBE_RMCS      0x03D00
 #define IXGBE_DPMCS     0x07F40
 #define IXGBE_PDPMCS    0x0CD00
@@ -2323,13 +2324,60 @@ typedef u32 ixgbe_physical_layer;
 #define IXGBE_PHYSICAL_LAYER_10GBASE_XAUI 0x1000
 #define IXGBE_PHYSICAL_LAYER_SFP_ACTIVE_DA 0x2000
 
-/* Flow Control Macros */
-#define PAUSE_RTT       8
-#define PAUSE_MTU(MTU)  ((MTU + 1024 - 1) / 1024)
+/* Flow Control Data Sheet defined values
+ * Calculation and defines taken from 802.1bb Annex O
+ */
+
+/* BitTimes (BT) conversion */
+#define IXGBE_BT2KB(BT) ((BT + 1023) / (8 * 1024))
+#define IXGBE_B2BT(BT) (BT * 8)
+
+/* Calculate Delay to respond to PFC */
+#define IXGBE_PFC_D     672
+
+/* Calculate Cable Delay */
+#define IXGBE_CABLE_DC  5556 /* Delay Copper */
+#define IXGBE_CABLE_DO  5000 /* Delay Optical */
+
+/* Calculate Interface Delay X540 */
+#define IXGBE_PHY_DC    25600   /* Delay 10G BASET */
+#define IXGBE_MAC_DC    8192    /* Delay Copper XAUI interface */
+#define IXGBE_XAUI_DC   (2 * 2048) /* Delay Copper Phy */
+
+#define IXGBE_ID_X540   (IXGBE_MAC_DC + IXGBE_XAUI_DC + IXGBE_PHY_DC)
+
+/* Calculate Interface Delay 82598, 82599 */
+#define IXGBE_PHY_D     12800
+#define IXGBE_MAC_D     4096
+#define IXGBE_XAUI_D    (2 * 1024)
+
+#define IXGBE_ID        (IXGBE_MAC_D + IXGBE_XAUI_D + IXGBE_PHY_D)
+
+/* Calculate Delay incurred from higher layer */
+#define IXGBE_HD        6144
+
+/* Calculate PCI Bus delay for low thresholds */
+#define IXGBE_PCI_DELAY 10000
+
+/* Calculate X540 delay value in bit times */
+#define IXGBE_FILL_RATE (36 / 25)
+
+#define IXGBE_DV_X540(LINK, TC) (IXGBE_FILL_RATE * \
+                                 (IXGBE_B2BT(LINK) + IXGBE_PFC_D + \
+                                 (2 * IXGBE_CABLE_DC) + \
+                                 (2 * IXGBE_ID_X540) + \
+                                 IXGBE_HD + IXGBE_B2BT(TC)))
+
+/* Calculate 82599, 82598 delay value in bit times */
+#define IXGBE_DV(LINK, TC) (IXGBE_FILL_RATE * \
+                            (IXGBE_B2BT(LINK) + IXGBE_PFC_D + \
+                            (2 * IXGBE_CABLE_DC) + (2 * IXGBE_ID) + \
+                            IXGBE_HD + IXGBE_B2BT(TC)))
 
-#define FC_HIGH_WATER(MTU) ((((PAUSE_RTT + PAUSE_MTU(MTU)) * 144) + 99) / 100 +\
-                                PAUSE_MTU(MTU))
-#define FC_LOW_WATER(MTU)  (2 * (2 * PAUSE_MTU(MTU) + PAUSE_RTT))
+/* Calculate low threshold delay values */
+#define IXGBE_LOW_DV_X540(TC) (2 * IXGBE_B2BT(TC) + \
+                               (IXGBE_FILL_RATE * IXGBE_PCI_DELAY))
+#define IXGBE_LOW_DV(TC)      (2 * IXGBE_LOW_DV_X540(TC))
 
 /* Software ATR hash keys */
 #define IXGBE_ATR_BUCKET_HASH_KEY    0x3DAD14E2
@@ -2548,7 +2596,7 @@ struct ixgbe_bus_info {
 
 /* Flow control parameters */
 struct ixgbe_fc_info {
-        u32 high_water; /* Flow Control High-water */
+        u32 high_water[MAX_TRAFFIC_CLASS]; /* Flow Control High-water */
         u32 low_water; /* Flow Control Low-water */
         u16 pause_time; /* Flow Control Pause timer */
         bool send_xon; /* Flow control send XON */