net/mlx5e: Support DCBNL IEEE ETS

Support the ndo_setup_tc callback and the needed methods
for multi TC/UP support, and removed the default_vlan_prio
from mlx5e_priv which is always 0, it was replaced with
hardcoded "0" in the new select queue method.

For that we now create MAX_NUM_TC num of TISs (one per prio)
on netdevice creation instead of priv->params.num_tc which
was always 1.

So far each channel had a single TXQ, Now each channel has a
TXQ per TC (Traffic Class).

Added en_dcbnl.c which implements the set/get DCBNL IEEE ETS,
set/get dcbx and registers the mlx5e dcbnl ops.

We still use the kernel's default TXQ selection method to select the
channel to transmit through but now we use our own method to select
the TXQ inside the channel based on VLAN priority.

In mlx5, as opposed to mlx4, tc group N gets lower priority than
tc group N+1.

CC: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Rana Shahout <ranas@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 190 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
new file mode 100644
index 000000000000..4f097da7e843
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_dcbnl.c
@@ -0,0 +1,190 @@
+/*
+ * Copyright (c) 2016, Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include <linux/device.h>
+#include <linux/netdevice.h>
+#include "en.h"
+
+#define MLX5E_MAX_PRIORITY 8
+
+static int mlx5e_dcbnl_ieee_getets(struct net_device *netdev,
+				   struct ieee_ets *ets)
+{
+	struct mlx5e_priv *priv = netdev_priv(netdev);
+
+	if (!MLX5_CAP_GEN(priv->mdev, ets))
+		return -ENOTSUPP;
+
+	memcpy(ets, &priv->params.ets, sizeof(*ets));
+	return 0;
+}
+
+enum {
+	MLX5E_VENDOR_TC_GROUP_NUM = 7,
+	MLX5E_ETS_TC_GROUP_NUM    = 0,
+};
+
+static void mlx5e_build_tc_group(struct ieee_ets *ets, u8 *tc_group, int max_tc)
+{
+	bool any_tc_mapped_to_ets = false;
+	int strict_group;
+	int i;
+
+	for (i = 0; i <= max_tc; i++)
+		if (ets->tc_tsa[i] == IEEE_8021QAZ_TSA_ETS)
+			any_tc_mapped_to_ets = true;
+
+	strict_group = any_tc_mapped_to_ets ? 1 : 0;
+
+	for (i = 0; i <= max_tc; i++) {
+		switch (ets->tc_tsa[i]) {
+		case IEEE_8021QAZ_TSA_VENDOR:
+			tc_group[i] = MLX5E_VENDOR_TC_GROUP_NUM;
+			break;
+		case IEEE_8021QAZ_TSA_STRICT:
+			tc_group[i] = strict_group++;
+			break;
+		case IEEE_8021QAZ_TSA_ETS:
+			tc_group[i] = MLX5E_ETS_TC_GROUP_NUM;
+			break;
+		}
+	}
+}
+
+static void mlx5e_build_tc_tx_bw(struct ieee_ets *ets, u8 *tc_tx_bw,
+				 u8 *tc_group, int max_tc)
+{
+	int i;
+
+	for (i = 0; i <= max_tc; i++) {
+		switch (ets->tc_tsa[i]) {
+		case IEEE_8021QAZ_TSA_VENDOR:
+			tc_tx_bw[i] = MLX5E_MAX_BW_ALLOC;
+			break;
+		case IEEE_8021QAZ_TSA_STRICT:
+			tc_tx_bw[i] = MLX5E_MAX_BW_ALLOC;
+			break;
+		case IEEE_8021QAZ_TSA_ETS:
+			tc_tx_bw[i] = ets->tc_tx_bw[i] ?: MLX5E_MIN_BW_ALLOC;
+			break;
+		}
+	}
+}
+
+int mlx5e_dcbnl_ieee_setets_core(struct mlx5e_priv *priv, struct ieee_ets *ets)
+{
+	struct mlx5_core_dev *mdev = priv->mdev;
+	u8 tc_tx_bw[IEEE_8021QAZ_MAX_TCS];
+	u8 tc_group[IEEE_8021QAZ_MAX_TCS];
+	int max_tc = mlx5_max_tc(mdev);
+	int err;
+
+	if (!MLX5_CAP_GEN(mdev, ets))
+		return -ENOTSUPP;
+
+	mlx5e_build_tc_group(ets, tc_group, max_tc);
+	mlx5e_build_tc_tx_bw(ets, tc_tx_bw, tc_group, max_tc);
+
+	err = mlx5_set_port_prio_tc(mdev, ets->prio_tc);
+	if (err)
+		return err;
+
+	err = mlx5_set_port_tc_group(mdev, tc_group);
+	if (err)
+		return err;
+
+	return mlx5_set_port_tc_bw_alloc(mdev, tc_tx_bw);
+}
+
+static int mlx5e_dbcnl_validate_ets(struct ieee_ets *ets)
+{
+	int bw_sum = 0;
+	int i;
+
+	/* Validate Priority */
+	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
+		if (ets->prio_tc[i] >= MLX5E_MAX_PRIORITY)
+			return -EINVAL;
+	}
+
+	/* Validate Bandwidth Sum */
+	for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
+		if (ets->tc_tsa[i] == IEEE_8021QAZ_TSA_ETS)
+			bw_sum += ets->tc_tx_bw[i];
+	}
+
+	if (bw_sum != 0 && bw_sum != 100)
+		return -EINVAL;
+	return 0;
+}
+
+static int mlx5e_dcbnl_ieee_setets(struct net_device *netdev,
+				   struct ieee_ets *ets)
+{
+	struct mlx5e_priv *priv = netdev_priv(netdev);
+	int err;
+
+	err = mlx5e_dbcnl_validate_ets(ets);
+	if (err)
+		return err;
+
+	err = mlx5e_dcbnl_ieee_setets_core(priv, ets);
+	if (err)
+		return err;
+
+	memcpy(&priv->params.ets, ets, sizeof(*ets));
+	priv->params.ets.ets_cap = mlx5_max_tc(priv->mdev) + 1;
+
+	return 0;
+}
+
+static u8 mlx5e_dcbnl_getdcbx(struct net_device *dev)
+{
+	return DCB_CAP_DCBX_HOST | DCB_CAP_DCBX_VER_IEEE;
+}
+
+static u8 mlx5e_dcbnl_setdcbx(struct net_device *dev, u8 mode)
+{
+	if ((mode & DCB_CAP_DCBX_LLD_MANAGED) ||
+	    (mode & DCB_CAP_DCBX_VER_CEE) ||
+	    !(mode & DCB_CAP_DCBX_VER_IEEE) ||
+	    !(mode & DCB_CAP_DCBX_HOST))
+		return 1;
+
+	return 0;
+}
+
+const struct dcbnl_rtnl_ops mlx5e_dcbnl_ops = {
+	.ieee_getets	= mlx5e_dcbnl_ieee_getets,
+	.ieee_setets	= mlx5e_dcbnl_ieee_setets,
+	.getdcbx	= mlx5e_dcbnl_getdcbx,
+	.setdcbx	= mlx5e_dcbnl_setdcbx,
+};