net/mlx5: support reading clock

Implements support for read_clock for the mlx5 driver. mlx5 supports
hardware timestamp offload, setting packets timestamp field to the
device clock. rte_eth_read_clock allows to read the device's current
clock value and therefore compare values on similar time base.

See rxtx_callbacks for an example.

Signed-off-by: Tom Barbette <[email protected]>
Acked-by: Shahaf Shuler <[email protected]>

Author: tbarbette

drivers/net/mlx5/mlx5.c

@@ -773,6 +773,7 @@ const struct eth_dev_ops mlx5_dev_ops = {
 	.xstats_get_names = mlx5_xstats_get_names,
 	.fw_version_get = mlx5_fw_version_get,
 	.dev_infos_get = mlx5_dev_infos_get,
+	.read_clock = mlx5_read_clock,
 	.dev_supported_ptypes_get = mlx5_dev_supported_ptypes_get,
 	.vlan_filter_set = mlx5_vlan_filter_set,
 	.rx_queue_setup = mlx5_rx_queue_setup,

drivers/net/mlx5/mlx5.h

@@ -404,6 +404,7 @@ int mlx5_set_flags(struct rte_eth_dev *dev, unsigned int keep,
 		   unsigned int flags);
 int mlx5_dev_configure(struct rte_eth_dev *dev);
 void mlx5_dev_infos_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *info);
+int mlx5_read_clock(struct rte_eth_dev *dev, uint64_t *clock);
 int mlx5_fw_version_get(struct rte_eth_dev *dev, char *fw_ver, size_t fw_size);
 const uint32_t *mlx5_dev_supported_ptypes_get(struct rte_eth_dev *dev);
 int mlx5_link_update(struct rte_eth_dev *dev, int wait_to_complete);

drivers/net/mlx5/mlx5_ethdev.c

@@ -568,6 +568,36 @@ mlx5_dev_infos_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *info)
 	}
 }
 
+/**
+ * Get device current raw clock counter
+ *
+ * @param dev
+ *   Pointer to Ethernet device structure.
+ * @param[out] time
+ *   Current raw clock counter of the device.
+ *
+ * @return
+ *   0 if the clock has correctly been read
+ *   The value of errno in case of error
+ */
+int
+mlx5_read_clock(struct rte_eth_dev *dev, uint64_t *clock)
+{
+	struct mlx5_priv *priv = dev->data->dev_private;
+	struct ibv_context *ctx = priv->sh->ctx;
+	struct ibv_values_ex values;
+	int err = 0;
+
+	values.comp_mask = IBV_VALUES_MASK_RAW_CLOCK;
+	err = mlx5_glue->query_rt_values_ex(ctx, &values);
+	if (err != 0) {
+		DRV_LOG(WARNING, "Could not query the clock !");
+		return err;
+	}
+	*clock = values.raw_clock.tv_nsec;
+	return 0;
+}
+
 /**
  * Get firmware version of a device.
  *

drivers/net/mlx5/mlx5_glue.c

@@ -87,6 +87,13 @@ mlx5_glue_query_device_ex(struct ibv_context *context,
 	return ibv_query_device_ex(context, input, attr);
 }
 
+static int
+mlx5_glue_query_rt_values_ex(struct ibv_context *context,
+			  struct ibv_values_ex *values)
+{
+	return ibv_query_rt_values_ex(context, values);
+}
+
 static int
 mlx5_glue_query_port(struct ibv_context *context, uint8_t port_num,
 		     struct ibv_port_attr *port_attr)
@@ -854,6 +861,7 @@ const struct mlx5_glue *mlx5_glue = &(const struct mlx5_glue){
 	.close_device = mlx5_glue_close_device,
 	.query_device = mlx5_glue_query_device,
 	.query_device_ex = mlx5_glue_query_device_ex,
+	.query_rt_values_ex = mlx5_glue_query_rt_values_ex,
 	.query_port = mlx5_glue_query_port,
 	.create_comp_channel = mlx5_glue_create_comp_channel,
 	.destroy_comp_channel = mlx5_glue_destroy_comp_channel,

drivers/net/mlx5/mlx5_glue.h

@@ -83,6 +83,8 @@ struct mlx5_glue {
 	int (*query_device_ex)(struct ibv_context *context,
 			       const struct ibv_query_device_ex_input *input,
 			       struct ibv_device_attr_ex *attr);
+	int (*query_rt_values_ex)(struct ibv_context *context,
+			       struct ibv_values_ex *values);
 	int (*query_port)(struct ibv_context *context, uint8_t port_num,
 			  struct ibv_port_attr *port_attr);
 	struct ibv_comp_channel *(*create_comp_channel)