net/mlx5e: Add PTP Hardware Clock (PHC) support

Add a PHC support to the mlx5_en driver. Use reader/writer spinlocks to
protect the timecounter since every packet received needs to call
timecounter_cycle2time() when timestamping is enabled.  This can become
a performance bottleneck with RSS and multiple receive queues if normal
spinlocks are used.

The driver has been tested with both Documentation/ptp/testptp and the
linuxptp project (http://linuxptp.sourceforge.net/) on a Mellanox
ConnectX-4 card.

Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
index 158c88c69ef91ce9e18db6441e0be176c0aaeba3..c503ea05e7427e866d8f26364ccf75f885a81823 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
@@ -13,6 +13,7 @@ config MLX5_CORE
 config MLX5_CORE_EN
        bool "Mellanox Technologies ConnectX-4 Ethernet support"
        depends on NETDEVICES && ETHERNET && PCI && MLX5_CORE
+       select PTP_1588_CLOCK
        default n
        ---help---
          Ethernet support in Mellanox Technologies ConnectX-4 NIC.

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 477e24884012f024fb35ceeb6ccf8f19b84d5ce3..9ea49a8933231808fff014f5a4570b7e380f5b44 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -34,6 +34,7 @@
 #include <linux/etherdevice.h>
 #include <linux/timecounter.h>
 #include <linux/net_tstamp.h>
+#include <linux/ptp_clock_kernel.h>
 #include <linux/mlx5/driver.h>
 #include <linux/mlx5/qp.h>
 #include <linux/mlx5/cq.h>
@@ -295,6 +296,8 @@ struct mlx5e_tstamp {
        unsigned long              overflow_period;
        struct delayed_work        overflow_work;
        struct mlx5_core_dev      *mdev;
+       struct ptp_clock          *ptp;
+       struct ptp_clock_info      ptp_info;
 };
 
 enum {

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c b/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
index 49a82385a6c0b6f436be50ce176570e2dc9daeaa..be6543570b2be18d476773f6b530dfeab6057800 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_clock.c
@@ -130,6 +130,89 @@ int mlx5e_hwstamp_get(struct net_device *dev, struct ifreq *ifr)
        return copy_to_user(ifr->ifr_data, cfg, sizeof(*cfg)) ? -EFAULT : 0;
 }
 
+static int mlx5e_ptp_settime(struct ptp_clock_info *ptp,
+                            const struct timespec64 *ts)
+{
+       struct mlx5e_tstamp *tstamp = container_of(ptp, struct mlx5e_tstamp,
+                                                  ptp_info);
+       u64 ns = timespec64_to_ns(ts);
+
+       write_lock(&tstamp->lock);
+       timecounter_init(&tstamp->clock, &tstamp->cycles, ns);
+       write_unlock(&tstamp->lock);
+
+       return 0;
+}
+
+static int mlx5e_ptp_gettime(struct ptp_clock_info *ptp,
+                            struct timespec64 *ts)
+{
+       struct mlx5e_tstamp *tstamp = container_of(ptp, struct mlx5e_tstamp,
+                                                  ptp_info);
+       u64 ns;
+
+       write_lock(&tstamp->lock);
+       ns = timecounter_read(&tstamp->clock);
+       write_unlock(&tstamp->lock);
+
+       *ts = ns_to_timespec64(ns);
+
+       return 0;
+}
+
+static int mlx5e_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+       struct mlx5e_tstamp *tstamp = container_of(ptp, struct mlx5e_tstamp,
+                                                  ptp_info);
+
+       write_lock(&tstamp->lock);
+       timecounter_adjtime(&tstamp->clock, delta);
+       write_unlock(&tstamp->lock);
+
+       return 0;
+}
+
+static int mlx5e_ptp_adjfreq(struct ptp_clock_info *ptp, s32 delta)
+{
+       u64 adj;
+       u32 diff;
+       int neg_adj = 0;
+       struct mlx5e_tstamp *tstamp = container_of(ptp, struct mlx5e_tstamp,
+                                                 ptp_info);
+
+       if (delta < 0) {
+               neg_adj = 1;
+               delta = -delta;
+       }
+
+       adj = tstamp->nominal_c_mult;
+       adj *= delta;
+       diff = div_u64(adj, 1000000000ULL);
+
+       write_lock(&tstamp->lock);
+       timecounter_read(&tstamp->clock);
+       tstamp->cycles.mult = neg_adj ? tstamp->nominal_c_mult - diff :
+                                       tstamp->nominal_c_mult + diff;
+       write_unlock(&tstamp->lock);
+
+       return 0;
+}
+
+static const struct ptp_clock_info mlx5e_ptp_clock_info = {
+       .owner          = THIS_MODULE,
+       .max_adj        = 100000000,
+       .n_alarm        = 0,
+       .n_ext_ts       = 0,
+       .n_per_out      = 0,
+       .n_pins         = 0,
+       .pps            = 0,
+       .adjfreq        = mlx5e_ptp_adjfreq,
+       .adjtime        = mlx5e_ptp_adjtime,
+       .gettime64      = mlx5e_ptp_gettime,
+       .settime64      = mlx5e_ptp_settime,
+       .enable         = NULL,
+};
+
 static void mlx5e_timestamp_init_config(struct mlx5e_tstamp *tstamp)
 {
        tstamp->hwtstamp_config.tx_type = HWTSTAMP_TX_OFF;
@@ -174,6 +257,18 @@ void mlx5e_timestamp_init(struct mlx5e_priv *priv)
                schedule_delayed_work(&tstamp->overflow_work, 0);
        else
                mlx5_core_warn(priv->mdev, "invalid overflow period, overflow_work is not scheduled\n");
+
+       /* Configure the PHC */
+       tstamp->ptp_info = mlx5e_ptp_clock_info;
+       snprintf(tstamp->ptp_info.name, 16, "mlx5 ptp");
+
+       tstamp->ptp = ptp_clock_register(&tstamp->ptp_info,
+                                        &priv->mdev->pdev->dev);
+       if (IS_ERR_OR_NULL(tstamp->ptp)) {
+               mlx5_core_warn(priv->mdev, "ptp_clock_register failed %ld\n",
+                              PTR_ERR(tstamp->ptp));
+               tstamp->ptp = NULL;
+       }
 }
 
 void mlx5e_timestamp_cleanup(struct mlx5e_priv *priv)
@@ -183,5 +278,10 @@ void mlx5e_timestamp_cleanup(struct mlx5e_priv *priv)
        if (!MLX5_CAP_GEN(priv->mdev, device_frequency_khz))
                return;
 
+       if (priv->tstamp.ptp) {
+               ptp_clock_unregister(priv->tstamp.ptp);
+               priv->tstamp.ptp = NULL;
+       }
+
        cancel_delayed_work_sync(&tstamp->overflow_work);
 }

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index a8a90f3c58075801b0d6a39ca7b0fbc7a8ef1652..65624ac65b4c347ac5dedf55f3b209de799e7e5f 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -865,7 +865,8 @@ static int mlx5e_get_ts_info(struct net_device *dev,
        if (ret)
                return ret;
 
-       info->phc_index = -1;
+       info->phc_index = priv->tstamp.ptp ?
+                         ptp_clock_index(priv->tstamp.ptp) : -1;
 
        if (!MLX5_CAP_GEN(priv->mdev, device_frequency_khz))
                return 0;