mlx4_core: Add link type autosensing

When a port's link is down (except to driver restart) and the port is
configured for auto sensing, we try to sense port link type (Ethernet
or InfiniBand) in order to determine how to initialize the port.  If
the port type needs to be changed, all mlx4 for the device interfaces
are unregistered and then registered again with the new port
types.  Sensing is done with intervals of 3 seconds.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/net/mlx4/sense.c b/drivers/net/mlx4/sense.c
new file mode 100644
index 0000000..6d5089e
--- /dev/null
+++ b/drivers/net/mlx4/sense.c
@@ -0,0 +1,156 @@
+/*
+ * Copyright (c) 2007 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/errno.h>
+#include <linux/if_ether.h>
+
+#include <linux/mlx4/cmd.h>
+
+#include "mlx4.h"
+
+static int mlx4_SENSE_PORT(struct mlx4_dev *dev, int port,
+			   enum mlx4_port_type *type)
+{
+	u64 out_param;
+	int err = 0;
+
+	err = mlx4_cmd_imm(dev, 0, &out_param, port, 0,
+			   MLX4_CMD_SENSE_PORT, MLX4_CMD_TIME_CLASS_B);
+	if (err) {
+		mlx4_err(dev, "Sense command failed for port: %d\n", port);
+		return err;
+	}
+
+	if (out_param > 2) {
+		mlx4_err(dev, "Sense returned illegal value: 0x%llx\n", out_param);
+		return EINVAL;
+	}
+
+	*type = out_param;
+	return 0;
+}
+
+void mlx4_do_sense_ports(struct mlx4_dev *dev,
+			 enum mlx4_port_type *stype,
+			 enum mlx4_port_type *defaults)
+{
+	struct mlx4_sense *sense = &mlx4_priv(dev)->sense;
+	int err;
+	int i;
+
+	for (i = 1; i <= dev->caps.num_ports; i++) {
+		stype[i - 1] = 0;
+		if (sense->do_sense_port[i] && sense->sense_allowed[i] &&
+		    dev->caps.possible_type[i] == MLX4_PORT_TYPE_AUTO) {
+			err = mlx4_SENSE_PORT(dev, i, &stype[i - 1]);
+			if (err)
+				stype[i - 1] = defaults[i - 1];
+		} else
+			stype[i - 1] = defaults[i - 1];
+	}
+
+	/*
+	 * Adjust port configuration:
+	 * If port 1 sensed nothing and port 2 is IB, set both as IB
+	 * If port 2 sensed nothing and port 1 is Eth, set both as Eth
+	 */
+	if (stype[0] == MLX4_PORT_TYPE_ETH) {
+		for (i = 1; i < dev->caps.num_ports; i++)
+			stype[i] = stype[i] ? stype[i] : MLX4_PORT_TYPE_ETH;
+	}
+	if (stype[dev->caps.num_ports - 1] == MLX4_PORT_TYPE_IB) {
+		for (i = 0; i < dev->caps.num_ports - 1; i++)
+			stype[i] = stype[i] ? stype[i] : MLX4_PORT_TYPE_IB;
+	}
+
+	/*
+	 * If sensed nothing, remain in current configuration.
+	 */
+	for (i = 0; i < dev->caps.num_ports; i++)
+		stype[i] = stype[i] ? stype[i] : defaults[i];
+
+}
+
+static void mlx4_sense_port(struct work_struct *work)
+{
+	struct delayed_work *delay = container_of(work, struct delayed_work, work);
+	struct mlx4_sense *sense = container_of(delay, struct mlx4_sense,
+						sense_poll);
+	struct mlx4_dev *dev = sense->dev;
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	enum mlx4_port_type stype[MLX4_MAX_PORTS];
+
+	mutex_lock(&priv->port_mutex);
+	mlx4_do_sense_ports(dev, stype, &dev->caps.port_type[1]);
+
+	if (mlx4_check_port_params(dev, stype))
+		goto sense_again;
+
+	if (mlx4_change_port_types(dev, stype))
+		mlx4_err(dev, "Failed to change port_types\n");
+
+sense_again:
+	mutex_unlock(&priv->port_mutex);
+	queue_delayed_work(mlx4_wq , &sense->sense_poll,
+			   round_jiffies_relative(MLX4_SENSE_RANGE));
+}
+
+void mlx4_start_sense(struct mlx4_dev *dev)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	struct mlx4_sense *sense = &priv->sense;
+
+	if (!(dev->caps.flags & MLX4_DEV_CAP_FLAG_DPDP))
+		return;
+
+	queue_delayed_work(mlx4_wq , &sense->sense_poll,
+			   round_jiffies_relative(MLX4_SENSE_RANGE));
+}
+
+void mlx4_stop_sense(struct mlx4_dev *dev)
+{
+	cancel_delayed_work_sync(&mlx4_priv(dev)->sense.sense_poll);
+}
+
+void  mlx4_sense_init(struct mlx4_dev *dev)
+{
+	struct mlx4_priv *priv = mlx4_priv(dev);
+	struct mlx4_sense *sense = &priv->sense;
+	int port;
+
+	sense->dev = dev;
+	for (port = 1; port <= dev->caps.num_ports; port++)
+		sense->do_sense_port[port] = 1;
+
+	INIT_DELAYED_WORK_DEFERRABLE(&sense->sense_poll, mlx4_sense_port);
+}