net/mlx4_en: Add HW timestamping (TS) support

The patch allows to enable/disable HW timestamping for incoming and/or
outgoing packets. It adds and initializes all structs and callbacks
needed by kernel TS API.
To enable/disable HW timestamping appropriate ioctl should be used.
Currently HWTSTAMP_FILTER_ALL/NONE and HWTSAMP_TX_ON/OFF only are
supported.
When enabling TS on receive flow - VLAN stripping will be disabled.
Also were made all relevant changes in RX/TX flows to consider TS request
and plant HW timestamps into relevant structures.
mlx4_ib was fixed to compile with new mlx4_cq_alloc() signature.

Signed-off-by: Eugenia Emantayev <eugenia@mellanox.com>
Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 132 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
new file mode 100644
index 000000000000..501c72f1fbeb
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2012 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/mlx4/device.h>
+
+#include "mlx4_en.h"
+
+int mlx4_en_timestamp_config(struct net_device *dev, int tx_type, int rx_filter)
+{
+	struct mlx4_en_priv *priv = netdev_priv(dev);
+	struct mlx4_en_dev *mdev = priv->mdev;
+	int port_up = 0;
+	int err = 0;
+
+	mutex_lock(&mdev->state_lock);
+	if (priv->port_up) {
+		port_up = 1;
+		mlx4_en_stop_port(dev, 1);
+	}
+
+	mlx4_en_free_resources(priv);
+
+	en_warn(priv, "Changing Time Stamp configuration\n");
+
+	priv->hwtstamp_config.tx_type = tx_type;
+	priv->hwtstamp_config.rx_filter = rx_filter;
+
+	if (rx_filter != HWTSTAMP_FILTER_NONE)
+		dev->features &= ~NETIF_F_HW_VLAN_CTAG_RX;
+	else
+		dev->features |= NETIF_F_HW_VLAN_CTAG_RX;
+
+	err = mlx4_en_alloc_resources(priv);
+	if (err) {
+		en_err(priv, "Failed reallocating port resources\n");
+		goto out;
+	}
+	if (port_up) {
+		err = mlx4_en_start_port(dev);
+		if (err)
+			en_err(priv, "Failed starting port\n");
+	}
+
+out:
+	mutex_unlock(&mdev->state_lock);
+	netdev_features_change(dev);
+	return err;
+}
+
+/* mlx4_en_read_clock - read raw cycle counter (to be used by time counter)
+ */
+static cycle_t mlx4_en_read_clock(const struct cyclecounter *tc)
+{
+	struct mlx4_en_dev *mdev =
+		container_of(tc, struct mlx4_en_dev, cycles);
+	struct mlx4_dev *dev = mdev->dev;
+
+	return mlx4_read_clock(dev) & tc->mask;
+}
+
+u64 mlx4_en_get_cqe_ts(struct mlx4_cqe *cqe)
+{
+	u64 hi, lo;
+	struct mlx4_ts_cqe *ts_cqe = (struct mlx4_ts_cqe *)cqe;
+
+	lo = (u64)be16_to_cpu(ts_cqe->timestamp_lo);
+	hi = ((u64)be32_to_cpu(ts_cqe->timestamp_hi) + !lo) << 16;
+
+	return hi | lo;
+}
+
+void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
+			    struct skb_shared_hwtstamps *hwts,
+			    u64 timestamp)
+{
+	u64 nsec;
+
+	nsec = timecounter_cyc2time(&mdev->clock, timestamp);
+
+	memset(hwts, 0, sizeof(struct skb_shared_hwtstamps));
+	hwts->hwtstamp = ns_to_ktime(nsec);
+}
+
+void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
+{
+	struct mlx4_dev *dev = mdev->dev;
+
+	memset(&mdev->cycles, 0, sizeof(mdev->cycles));
+	mdev->cycles.read = mlx4_en_read_clock;
+	mdev->cycles.mask = CLOCKSOURCE_MASK(48);
+	/* Using shift to make calculation more accurate. Since current HW
+	 * clock frequency is 427 MHz, and cycles are given using a 48 bits
+	 * register, the biggest shift when calculating using u64, is 14
+	 * (max_cycles * multiplier < 2^64)
+	 */
+	mdev->cycles.shift = 14;
+	mdev->cycles.mult =
+		clocksource_khz2mult(1000 * dev->caps.hca_core_clock, mdev->cycles.shift);
+
+	timecounter_init(&mdev->clock, &mdev->cycles,
+			 ktime_to_ns(ktime_get_real()));
+}