fm10k: Add support for IEEE DCBx

This patch adds support for management of the limited QOS features of the
FM10000 interface.  Specifically we can support up to 8 traffic classes,
however the part only provides 1 Rx and 1 Tx FIFO in the host interface and
as a result this can lead to head-of-line blocking on Rx.  This can be
avoided by setting PFC only for priorities that cannot afford to drop
frames.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

4 files changed, 185 insertions, 4 deletions

diff --git a/drivers/net/ethernet/intel/fm10k/Makefile b/drivers/net/ethernet/intel/fm10k/Makefile
index 70565abfc62a..502362584165 100644
--- a/drivers/net/ethernet/intel/fm10k/Makefile
+++ b/drivers/net/ethernet/intel/fm10k/Makefile
@@ -29,4 +29,5 @@ obj-$(CONFIG_FM10K) += fm10k.o
 
 fm10k-objs := fm10k_main.o fm10k_common.o fm10k_pci.o \
               fm10k_netdev.o fm10k_ethtool.o fm10k_pf.o fm10k_vf.o \
-              fm10k_mbx.o fm10k_iov.o fm10k_tlv.o
+              fm10k_mbx.o fm10k_iov.o fm10k_tlv.o \
+              fm10k_dcbnl.o
diff --git a/drivers/net/ethernet/intel/fm10k/fm10k.h b/drivers/net/ethernet/intel/fm10k/fm10k.h
index fb718719c196..33a59493094c 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k.h
+++ b/drivers/net/ethernet/intel/fm10k/fm10k.h
@@ -307,7 +307,7 @@ struct fm10k_intfc {
         /* VXLAN port tracking information */
         struct list_head vxlan_port;
 
-#if defined(HAVE_DCBNL_IEEE) && defined(CONFIG_DCB)
+#ifdef CONFIG_DCB
         u8 pfc_en;
 #endif
         u8 rx_pause;
@@ -467,4 +467,7 @@ int fm10k_ndo_set_vf_bw(struct net_device *netdev, int vf_idx, int rate,
                         int unused);
 int fm10k_ndo_get_vf_config(struct net_device *netdev,
                             int vf_idx, struct ifla_vf_info *ivi);
+
+/* DCB */
+void fm10k_dcbnl_set_ops(struct net_device *dev);
 #endif /* _FM10K_H_ */
diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_dcbnl.c b/drivers/net/ethernet/intel/fm10k/fm10k_dcbnl.c
new file mode 100644
index 000000000000..212a92dad222
--- /dev/null
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_dcbnl.c
@@ -0,0 +1,174 @@
+/* Intel Ethernet Switch Host Interface Driver
+ * Copyright(c) 2013 - 2014 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Contact Information:
+ * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ */
+
+#include "fm10k.h"
+
+#ifdef CONFIG_DCB
+/**
+ * fm10k_dcbnl_ieee_getets - get the ETS configuration for the device
+ * @dev: netdev interface for the device
+ * @ets: ETS structure to push configuration to
+ **/
+static int fm10k_dcbnl_ieee_getets(struct net_device *dev, struct ieee_ets *ets)
+{
+        int i;
+
+        /* we support 8 TCs in all modes */
+        ets->ets_cap = IEEE_8021QAZ_MAX_TCS;
+        ets->cbs = 0;
+
+        /* we only support strict priority and cannot do traffic shaping */
+        memset(ets->tc_tx_bw, 0, sizeof(ets->tc_tx_bw));
+        memset(ets->tc_rx_bw, 0, sizeof(ets->tc_rx_bw));
+        memset(ets->tc_tsa, IEEE_8021QAZ_TSA_STRICT, sizeof(ets->tc_tsa));
+
+        /* populate the prio map based on the netdev */
+        for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++)
+                ets->prio_tc[i] = netdev_get_prio_tc_map(dev, i);
+
+        return 0;
+}
+
+/**
+ * fm10k_dcbnl_ieee_setets - set the ETS configuration for the device
+ * @dev: netdev interface for the device
+ * @ets: ETS structure to pull configuration from
+ **/
+static int fm10k_dcbnl_ieee_setets(struct net_device *dev, struct ieee_ets *ets)
+{
+        u8 num_tc = 0;
+        int i, err;
+
+        /* verify type and determine num_tcs needed */
+        for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
+                if (ets->tc_tx_bw[i] || ets->tc_rx_bw[i])
+                        return -EINVAL;
+                if (ets->tc_tsa[i] != IEEE_8021QAZ_TSA_STRICT)
+                        return -EINVAL;
+                if (ets->prio_tc[i] > num_tc)
+                        num_tc = ets->prio_tc[i];
+        }
+
+        /* if requested TC is greater than 0 then num_tcs is max + 1 */
+        if (num_tc)
+                num_tc++;
+
+        if (num_tc > IEEE_8021QAZ_MAX_TCS)
+                return -EINVAL;
+
+        /* update TC hardware mapping if necessary */
+        if (num_tc != netdev_get_num_tc(dev)) {
+                err = fm10k_setup_tc(dev, num_tc);
+                if (err)
+                        return err;
+        }
+
+        /* update priority mapping */
+        for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++)
+                netdev_set_prio_tc_map(dev, i, ets->prio_tc[i]);
+
+        return 0;
+}
+
+/**
+ * fm10k_dcbnl_ieee_getpfc - get the PFC configuration for the device
+ * @dev: netdev interface for the device
+ * @pfc: PFC structure to push configuration to
+ **/
+static int fm10k_dcbnl_ieee_getpfc(struct net_device *dev, struct ieee_pfc *pfc)
+{
+        struct fm10k_intfc *interface = netdev_priv(dev);
+
+        /* record flow control max count and state of TCs */
+        pfc->pfc_cap = IEEE_8021QAZ_MAX_TCS;
+        pfc->pfc_en = interface->pfc_en;
+
+        return 0;
+}
+
+/**
+ * fm10k_dcbnl_ieee_setpfc - set the PFC configuration for the device
+ * @dev: netdev interface for the device
+ * @pfc: PFC structure to pull configuration from
+ **/
+static int fm10k_dcbnl_ieee_setpfc(struct net_device *dev, struct ieee_pfc *pfc)
+{
+        struct fm10k_intfc *interface = netdev_priv(dev);
+
+        /* record PFC configuration to interface */
+        interface->pfc_en = pfc->pfc_en;
+
+        /* if we are running update the drop_en state for all queues */
+        if (netif_running(dev))
+                fm10k_update_rx_drop_en(interface);
+
+        return 0;
+}
+
+/**
+ * fm10k_dcbnl_ieee_getdcbx - get the DCBX configuration for the device
+ * @dev: netdev interface for the device
+ *
+ * Returns that we support only IEEE DCB for this interface
+ **/
+static u8 fm10k_dcbnl_getdcbx(struct net_device *dev)
+{
+        return DCB_CAP_DCBX_HOST | DCB_CAP_DCBX_VER_IEEE;
+}
+
+/**
+ * fm10k_dcbnl_ieee_setdcbx - get the DCBX configuration for the device
+ * @dev: netdev interface for the device
+ * @mode: new mode for this device
+ *
+ * Returns error on attempt to enable anything but IEEE DCB for this interface
+ **/
+static u8 fm10k_dcbnl_setdcbx(struct net_device *dev, u8 mode)
+{
+        return (mode != (DCB_CAP_DCBX_HOST | DCB_CAP_DCBX_VER_IEEE)) ? 1 : 0;
+}
+
+static const struct dcbnl_rtnl_ops fm10k_dcbnl_ops = {
+        .ieee_getets    = fm10k_dcbnl_ieee_getets,
+        .ieee_setets    = fm10k_dcbnl_ieee_setets,
+        .ieee_getpfc    = fm10k_dcbnl_ieee_getpfc,
+        .ieee_setpfc    = fm10k_dcbnl_ieee_setpfc,
+
+        .getdcbx        = fm10k_dcbnl_getdcbx,
+        .setdcbx        = fm10k_dcbnl_setdcbx,
+};
+
+#endif /* CONFIG_DCB */
+/**
+ * fm10k_dcbnl_set_ops - Configures dcbnl ops pointer for netdev
+ * @dev: netdev interface for the device
+ *
+ * Enables PF for DCB by assigning DCBNL ops pointer.
+ **/
+void fm10k_dcbnl_set_ops(struct net_device *dev)
+{
+#ifdef CONFIG_DCB
+        struct fm10k_intfc *interface = netdev_priv(dev);
+        struct fm10k_hw *hw = &interface->hw;
+
+        if (hw->mac.type == fm10k_mac_pf)
+                dev->dcbnl_ops = &fm10k_dcbnl_ops;
+#endif /* CONFIG_DCB */
+}
diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c
index 7935c1aad6d5..04ca7f2ab385 100644
--- a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c
+++ b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c
@@ -649,7 +649,7 @@ static void fm10k_configure_rx_ring(struct fm10k_intfc *interface,
         fm10k_write_reg(hw, FM10K_SRRCTL(reg_idx), srrctl);
 
         /* Enable drop on empty */
-#if defined(HAVE_DCBNL_IEEE) && defined(CONFIG_DCB)
+#ifdef CONFIG_DCB
         if (interface->pfc_en)
                 rx_pause = interface->pfc_en;
 #endif
@@ -688,7 +688,7 @@ void fm10k_update_rx_drop_en(struct fm10k_intfc *interface)
         u8 rx_pause = interface->rx_pause;
         int i;
 
-#if defined(HAVE_DCBNL_IEEE) && defined(CONFIG_DCB)
+#ifdef CONFIG_DCB
         if (interface->pfc_en)
                 rx_pause = interface->pfc_en;
 
@@ -1556,6 +1556,9 @@ static int fm10k_sw_init(struct fm10k_intfc *interface,
                 netdev->hw_features &= ~NETIF_F_GSO_UDP_TUNNEL;
         }
 
+        /* initialize DCBNL interface */
+        fm10k_dcbnl_set_ops(netdev);
+
         /* Initialize service timer and service task */
         set_bit(__FM10K_SERVICE_DISABLE, &interface->state);
         setup_timer(&interface->service_timer, &fm10k_service_timer,