[PATCH net-next v4 0/2] mlx4_en: Add PTP support

[PATCH net-next v4 0/2] mlx4_en: Add PTP support

[Shawn Bohrer]

From: Shawn Bohrer <sbohrer@rgmadvisors.com>

This adds support to the mlx4_en driver to support running a PTP client
with hardware timestamp support.  It also allows synchronization of the
hardware timestamped packets with the system clock.

v2:
* Implemented mlx4_en_phc_adjfreq() in software.
* Protected timecounter with a spinlock
* Set the phc_index in mlx4_en_get_ts_info()
* Use a hard-coded ptp_clock_info.name

v3: is code identical to v2.  I simply finished testing it with
linuxptp, cleaned up the commit description a little and sent to davem.

v4:
* Initialize clock_lock
* Use reader/writer spinlock for clock_lock to improve performance when
 timetamping is enabled.

Shawn Bohrer (2):
  mlx4_en: Add PTP hardware clock
  mlx4_en: Only cycle port if HW timestamp config changes

 drivers/net/ethernet/mellanox/mlx4/en_clock.c   |  198 ++++++++++++++++++++++-
 drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |    3 +
 drivers/net/ethernet/mellanox/mlx4/en_main.c    |    3 +
 drivers/net/ethernet/mellanox/mlx4/mlx4_en.h    |    6 +
 4 files changed, 202 insertions(+), 8 deletions(-)

-- 
1.7.7.6

[PATCH net-next v4 1/2] mlx4_en: Add PTP hardware clock

[Shawn Bohrer]

From: Shawn Bohrer <sbohrer@rgmadvisors.com>

This adds a PHC to the mlx4_en driver. We 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.

This driver has been tested with both Documentation/ptp/testptp and the
linuxptp project (http://linuxptp.sourceforge.net/) on a Mellanox
ConnectX-3 card.

Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_clock.c   |  194 ++++++++++++++++++++++-
 drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |    3 +
 drivers/net/ethernet/mellanox/mlx4/en_main.c    |    3 +
 drivers/net/ethernet/mellanox/mlx4/mlx4_en.h    |    6 +
 4 files changed, 198 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
index fd64410..30712b3 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
@@ -103,19 +103,191 @@ void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
 			    struct skb_shared_hwtstamps *hwts,
 			    u64 timestamp)
 {
+	unsigned long flags;
 	u64 nsec;
 
+	read_lock_irqsave(&mdev->clock_lock, flags);
 	nsec = timecounter_cyc2time(&mdev->clock, timestamp);
+	read_unlock_irqrestore(&mdev->clock_lock, flags);
 
 	memset(hwts, 0, sizeof(struct skb_shared_hwtstamps));
 	hwts->hwtstamp = ns_to_ktime(nsec);
 }
 
+/**
+ * mlx4_en_remove_timestamp - disable PTP device
+ * @mdev: board private structure
+ *
+ * Stop the PTP support.
+ **/
+void mlx4_en_remove_timestamp(struct mlx4_en_dev *mdev)
+{
+	if (mdev->ptp_clock) {
+		ptp_clock_unregister(mdev->ptp_clock);
+		mdev->ptp_clock = NULL;
+		mlx4_info(mdev, "removed PHC\n");
+	}
+}
+
+void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev)
+{
+	bool timeout = time_is_before_jiffies(mdev->last_overflow_check +
+					      mdev->overflow_period);
+	unsigned long flags;
+
+	if (timeout) {
+		write_lock_irqsave(&mdev->clock_lock, flags);
+		timecounter_read(&mdev->clock);
+		write_unlock_irqrestore(&mdev->clock_lock, flags);
+		mdev->last_overflow_check = jiffies;
+	}
+}
+
+/**
+ * mlx4_en_phc_adjfreq - adjust the frequency of the hardware clock
+ * @ptp: ptp clock structure
+ * @delta: Desired frequency change in parts per billion
+ *
+ * Adjust the frequency of the PHC cycle counter by the indicated delta from
+ * the base frequency.
+ **/
+static int mlx4_en_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
+{
+	u64 adj;
+	u32 diff, mult;
+	int neg_adj = 0;
+	unsigned long flags;
+	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
+						ptp_clock_info);
+
+	if (delta < 0) {
+		neg_adj = 1;
+		delta = -delta;
+	}
+	mult = mdev->nominal_c_mult;
+	adj = mult;
+	adj *= delta;
+	diff = div_u64(adj, 1000000000ULL);
+
+	write_lock_irqsave(&mdev->clock_lock, flags);
+	timecounter_read(&mdev->clock);
+	mdev->cycles.mult = neg_adj ? mult - diff : mult + diff;
+	write_unlock_irqrestore(&mdev->clock_lock, flags);
+
+	return 0;
+}
+
+/**
+ * mlx4_en_phc_adjtime - Shift the time of the hardware clock
+ * @ptp: ptp clock structure
+ * @delta: Desired change in nanoseconds
+ *
+ * Adjust the timer by resetting the timecounter structure.
+ **/
+static int mlx4_en_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
+{
+	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
+						ptp_clock_info);
+	unsigned long flags;
+	s64 now;
+
+	write_lock_irqsave(&mdev->clock_lock, flags);
+	now = timecounter_read(&mdev->clock);
+	now += delta;
+	timecounter_init(&mdev->clock, &mdev->cycles, now);
+	write_unlock_irqrestore(&mdev->clock_lock, flags);
+
+	return 0;
+}
+
+/**
+ * mlx4_en_phc_gettime - Reads the current time from the hardware clock
+ * @ptp: ptp clock structure
+ * @ts: timespec structure to hold the current time value
+ *
+ * Read the timecounter and return the correct value in ns after converting
+ * it into a struct timespec.
+ **/
+static int mlx4_en_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
+{
+	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
+						ptp_clock_info);
+	unsigned long flags;
+	u32 remainder;
+	u64 ns;
+
+	write_lock_irqsave(&mdev->clock_lock, flags);
+	ns = timecounter_read(&mdev->clock);
+	write_unlock_irqrestore(&mdev->clock_lock, flags);
+
+	ts->tv_sec = div_u64_rem(ns, NSEC_PER_SEC, &remainder);
+	ts->tv_nsec = remainder;
+
+	return 0;
+}
+
+/**
+ * mlx4_en_phc_settime - Set the current time on the hardware clock
+ * @ptp: ptp clock structure
+ * @ts: timespec containing the new time for the cycle counter
+ *
+ * Reset the timecounter to use a new base value instead of the kernel
+ * wall timer value.
+ **/
+static int mlx4_en_phc_settime(struct ptp_clock_info *ptp,
+			       const struct timespec *ts)
+{
+	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
+						ptp_clock_info);
+	u64 ns = timespec_to_ns(ts);
+	unsigned long flags;
+
+	/* reset the timecounter */
+	write_lock_irqsave(&mdev->clock_lock, flags);
+	timecounter_init(&mdev->clock, &mdev->cycles, ns);
+	write_unlock_irqrestore(&mdev->clock_lock, flags);
+
+	return 0;
+}
+
+/**
+ * mlx4_en_phc_enable - enable or disable an ancillary feature
+ * @ptp: ptp clock structure
+ * @request: Desired resource to enable or disable
+ * @on: Caller passes one to enable or zero to disable
+ *
+ * Enable (or disable) ancillary features of the PHC subsystem.
+ * Currently, no ancillary features are supported.
+ **/
+static int mlx4_en_phc_enable(struct ptp_clock_info __always_unused *ptp,
+			      struct ptp_clock_request __always_unused *request,
+			      int __always_unused on)
+{
+	return -EOPNOTSUPP;
+}
+
+static const struct ptp_clock_info mlx4_en_ptp_clock_info = {
+	.owner		= THIS_MODULE,
+	.max_adj	= 100000000,
+	.n_alarm	= 0,
+	.n_ext_ts	= 0,
+	.n_per_out	= 0,
+	.pps		= 0,
+	.adjfreq	= mlx4_en_phc_adjfreq,
+	.adjtime	= mlx4_en_phc_adjtime,
+	.gettime	= mlx4_en_phc_gettime,
+	.settime	= mlx4_en_phc_settime,
+	.enable		= mlx4_en_phc_enable,
+};
+
 void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
 {
 	struct mlx4_dev *dev = mdev->dev;
+	unsigned long flags;
 	u64 ns;
 
+	rwlock_init(&mdev->clock_lock);
+
 	memset(&mdev->cycles, 0, sizeof(mdev->cycles));
 	mdev->cycles.read = mlx4_en_read_clock;
 	mdev->cycles.mask = CLOCKSOURCE_MASK(48);
@@ -127,9 +299,12 @@ void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
 	mdev->cycles.shift = 14;
 	mdev->cycles.mult =
 		clocksource_khz2mult(1000 * dev->caps.hca_core_clock, mdev->cycles.shift);
+	mdev->nominal_c_mult = mdev->cycles.mult;
 
+	write_lock_irqsave(&mdev->clock_lock, flags);
 	timecounter_init(&mdev->clock, &mdev->cycles,
 			 ktime_to_ns(ktime_get_real()));
+	write_unlock_irqrestore(&mdev->clock_lock, flags);
 
 	/* Calculate period in seconds to call the overflow watchdog - to make
 	 * sure counter is checked at least once every wrap around.
@@ -137,15 +312,18 @@ void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
 	ns = cyclecounter_cyc2ns(&mdev->cycles, mdev->cycles.mask);
 	do_div(ns, NSEC_PER_SEC / 2 / HZ);
 	mdev->overflow_period = ns;
-}
 
-void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev)
-{
-	bool timeout = time_is_before_jiffies(mdev->last_overflow_check +
-					      mdev->overflow_period);
+	/* Configure the PHC */
+	mdev->ptp_clock_info = mlx4_en_ptp_clock_info;
+	snprintf(mdev->ptp_clock_info.name, 16, "mlx4 ptp");
 
-	if (timeout) {
-		timecounter_read(&mdev->clock);
-		mdev->last_overflow_check = jiffies;
+	mdev->ptp_clock = ptp_clock_register(&mdev->ptp_clock_info,
+					     &mdev->pdev->dev);
+	if (IS_ERR(mdev->ptp_clock)) {
+		mdev->ptp_clock = NULL;
+		mlx4_err(mdev, "ptp_clock_register failed\n");
+	} else {
+		mlx4_info(mdev, "registered PHC clock\n");
 	}
+
 }
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
index 0596f9f..3e8d336 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
@@ -1193,6 +1193,9 @@ static int mlx4_en_get_ts_info(struct net_device *dev,
 		info->rx_filters =
 			(1 << HWTSTAMP_FILTER_NONE) |
 			(1 << HWTSTAMP_FILTER_ALL);
+
+		if (mdev->ptp_clock)
+			info->phc_index = ptp_clock_index(mdev->ptp_clock);
 	}
 
 	return ret;
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_main.c b/drivers/net/ethernet/mellanox/mlx4/en_main.c
index 725a4e1..d357bf5 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_main.c
@@ -199,6 +199,9 @@ static void mlx4_en_remove(struct mlx4_dev *dev, void *endev_ptr)
 		if (mdev->pndev[i])
 			mlx4_en_destroy_netdev(mdev->pndev[i]);
 
+	if (mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_TS)
+		mlx4_en_remove_timestamp(mdev);
+
 	flush_workqueue(mdev->workqueue);
 	destroy_workqueue(mdev->workqueue);
 	(void) mlx4_mr_free(dev, &mdev->mr);
diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 123714c..298ce22 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -45,6 +45,7 @@
 #include <linux/dcbnl.h>
 #endif
 #include <linux/cpu_rmap.h>
+#include <linux/ptp_clock_kernel.h>
 
 #include <linux/mlx4/device.h>
 #include <linux/mlx4/qp.h>
@@ -375,10 +376,14 @@ struct mlx4_en_dev {
 	u32                     priv_pdn;
 	spinlock_t              uar_lock;
 	u8			mac_removed[MLX4_MAX_PORTS + 1];
+	rwlock_t		clock_lock;
+	u32			nominal_c_mult;
 	struct cyclecounter	cycles;
 	struct timecounter	clock;
 	unsigned long		last_overflow_check;
 	unsigned long		overflow_period;
+	struct ptp_clock	*ptp_clock;
+	struct ptp_clock_info	ptp_clock_info;
 };
 
 
@@ -790,6 +795,7 @@ void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
 			    struct skb_shared_hwtstamps *hwts,
 			    u64 timestamp);
 void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev);
+void mlx4_en_remove_timestamp(struct mlx4_en_dev *mdev);
 int mlx4_en_timestamp_config(struct net_device *dev,
 			     int tx_type,
 			     int rx_filter);
-- 
1.7.7.6

Re: mlx4_en: Add PTP hardware clock

[Hadar Hen-Zion]

On 31/12/13 11:39 -0600, Shawn Bohrer wrote:
> From: Shawn Bohrer <sbohrer@rgmadvisors.com>
> 
> This adds a PHC to the mlx4_en driver. We 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.
> 
> This driver has been tested with both Documentation/ptp/testptp and the
> linuxptp project (http://linuxptp.sourceforge.net/) on a Mellanox
> ConnectX-3 card.
> 
> Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
> ---
>  drivers/net/ethernet/mellanox/mlx4/en_clock.c   |  194 ++++++++++++++++++++++-
>  drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |    3 +
>  drivers/net/ethernet/mellanox/mlx4/en_main.c    |    3 +
>  drivers/net/ethernet/mellanox/mlx4/mlx4_en.h    |    6 +
>  4 files changed, 198 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> index fd64410..30712b3 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> @@ -103,19 +103,191 @@ void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
>  			    struct skb_shared_hwtstamps *hwts,
>  			    u64 timestamp)
>  {
> +	unsigned long flags;
>  	u64 nsec;
>  
> +	read_lock_irqsave(&mdev->clock_lock, flags);
>  	nsec = timecounter_cyc2time(&mdev->clock, timestamp);
> +	read_unlock_irqrestore(&mdev->clock_lock, flags);
>  
>  	memset(hwts, 0, sizeof(struct skb_shared_hwtstamps));
>  	hwts->hwtstamp = ns_to_ktime(nsec);
>  }
>  
> +/**
> + * mlx4_en_remove_timestamp - disable PTP device
> + * @mdev: board private structure
> + *
> + * Stop the PTP support.
> + **/
> +void mlx4_en_remove_timestamp(struct mlx4_en_dev *mdev)
> +{
> +	if (mdev->ptp_clock) {
> +		ptp_clock_unregister(mdev->ptp_clock);
> +		mdev->ptp_clock = NULL;
> +		mlx4_info(mdev, "removed PHC\n");
> +	}
> +}
> +
> +void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev)
> +{
> +	bool timeout = time_is_before_jiffies(mdev->last_overflow_check +
> +					      mdev->overflow_period);
> +	unsigned long flags;
> +
> +	if (timeout) {
> +		write_lock_irqsave(&mdev->clock_lock, flags);
> +		timecounter_read(&mdev->clock);
> +		write_unlock_irqrestore(&mdev->clock_lock, flags);
> +		mdev->last_overflow_check = jiffies;
> +	}
> +}
> +
> +/**
> + * mlx4_en_phc_adjfreq - adjust the frequency of the hardware clock
> + * @ptp: ptp clock structure
> + * @delta: Desired frequency change in parts per billion
> + *
> + * Adjust the frequency of the PHC cycle counter by the indicated delta from
> + * the base frequency.
> + **/
> +static int mlx4_en_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
> +{
> +	u64 adj;
> +	u32 diff, mult;
> +	int neg_adj = 0;
> +	unsigned long flags;
> +	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
> +						ptp_clock_info);
> +
> +	if (delta < 0) {
> +		neg_adj = 1;
> +		delta = -delta;
> +	}
> +	mult = mdev->nominal_c_mult;
> +	adj = mult;
> +	adj *= delta;
> +	diff = div_u64(adj, 1000000000ULL);
> +
> +	write_lock_irqsave(&mdev->clock_lock, flags);
> +	timecounter_read(&mdev->clock);
> +	mdev->cycles.mult = neg_adj ? mult - diff : mult + diff;
> +	write_unlock_irqrestore(&mdev->clock_lock, flags);
> +
> +	return 0;
> +}
> +
> +/**
> + * mlx4_en_phc_adjtime - Shift the time of the hardware clock
> + * @ptp: ptp clock structure
> + * @delta: Desired change in nanoseconds
> + *
> + * Adjust the timer by resetting the timecounter structure.
> + **/
> +static int mlx4_en_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
> +{
> +	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
> +						ptp_clock_info);
> +	unsigned long flags;
> +	s64 now;
> +
> +	write_lock_irqsave(&mdev->clock_lock, flags);
> +	now = timecounter_read(&mdev->clock);
> +	now += delta;
> +	timecounter_init(&mdev->clock, &mdev->cycles, now);
> +	write_unlock_irqrestore(&mdev->clock_lock, flags);
> +
> +	return 0;
> +}
> +
> +/**
> + * mlx4_en_phc_gettime - Reads the current time from the hardware clock
> + * @ptp: ptp clock structure
> + * @ts: timespec structure to hold the current time value
> + *
> + * Read the timecounter and return the correct value in ns after converting
> + * it into a struct timespec.
> + **/
> +static int mlx4_en_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
> +{
> +	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
> +						ptp_clock_info);
> +	unsigned long flags;
> +	u32 remainder;
> +	u64 ns;
> +
> +	write_lock_irqsave(&mdev->clock_lock, flags);
> +	ns = timecounter_read(&mdev->clock);
> +	write_unlock_irqrestore(&mdev->clock_lock, flags);
> +
> +	ts->tv_sec = div_u64_rem(ns, NSEC_PER_SEC, &remainder);
> +	ts->tv_nsec = remainder;
> +
> +	return 0;
> +}
> +
> +/**
> + * mlx4_en_phc_settime - Set the current time on the hardware clock
> + * @ptp: ptp clock structure
> + * @ts: timespec containing the new time for the cycle counter
> + *
> + * Reset the timecounter to use a new base value instead of the kernel
> + * wall timer value.
> + **/
> +static int mlx4_en_phc_settime(struct ptp_clock_info *ptp,
> +			       const struct timespec *ts)
> +{
> +	struct mlx4_en_dev *mdev = container_of(ptp, struct mlx4_en_dev,
> +						ptp_clock_info);
> +	u64 ns = timespec_to_ns(ts);
> +	unsigned long flags;
> +
> +	/* reset the timecounter */
> +	write_lock_irqsave(&mdev->clock_lock, flags);
> +	timecounter_init(&mdev->clock, &mdev->cycles, ns);
> +	write_unlock_irqrestore(&mdev->clock_lock, flags);
> +
> +	return 0;
> +}
> +
> +/**
> + * mlx4_en_phc_enable - enable or disable an ancillary feature
> + * @ptp: ptp clock structure
> + * @request: Desired resource to enable or disable
> + * @on: Caller passes one to enable or zero to disable
> + *
> + * Enable (or disable) ancillary features of the PHC subsystem.
> + * Currently, no ancillary features are supported.
> + **/
> +static int mlx4_en_phc_enable(struct ptp_clock_info __always_unused *ptp,
> +			      struct ptp_clock_request __always_unused *request,
> +			      int __always_unused on)
> +{
> +	return -EOPNOTSUPP;
> +}
> +
> +static const struct ptp_clock_info mlx4_en_ptp_clock_info = {
> +	.owner		= THIS_MODULE,
> +	.max_adj	= 100000000,
> +	.n_alarm	= 0,
> +	.n_ext_ts	= 0,
> +	.n_per_out	= 0,
> +	.pps		= 0,
> +	.adjfreq	= mlx4_en_phc_adjfreq,
> +	.adjtime	= mlx4_en_phc_adjtime,
> +	.gettime	= mlx4_en_phc_gettime,
> +	.settime	= mlx4_en_phc_settime,
> +	.enable		= mlx4_en_phc_enable,
> +};
> +
>  void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
>  {
>  	struct mlx4_dev *dev = mdev->dev;
> +	unsigned long flags;
>  	u64 ns;
>  
> +	rwlock_init(&mdev->clock_lock);
> +
>  	memset(&mdev->cycles, 0, sizeof(mdev->cycles));
>  	mdev->cycles.read = mlx4_en_read_clock;
>  	mdev->cycles.mask = CLOCKSOURCE_MASK(48);
> @@ -127,9 +299,12 @@ void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
>  	mdev->cycles.shift = 14;
>  	mdev->cycles.mult =
>  		clocksource_khz2mult(1000 * dev->caps.hca_core_clock, mdev->cycles.shift);
> +	mdev->nominal_c_mult = mdev->cycles.mult;
>  
> +	write_lock_irqsave(&mdev->clock_lock, flags);
>  	timecounter_init(&mdev->clock, &mdev->cycles,
>  			 ktime_to_ns(ktime_get_real()));
> +	write_unlock_irqrestore(&mdev->clock_lock, flags);
>  
>  	/* Calculate period in seconds to call the overflow watchdog - to make
>  	 * sure counter is checked at least once every wrap around.
> @@ -137,15 +312,18 @@ void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev)
>  	ns = cyclecounter_cyc2ns(&mdev->cycles, mdev->cycles.mask);
>  	do_div(ns, NSEC_PER_SEC / 2 / HZ);
>  	mdev->overflow_period = ns;
> -}
>  
> -void mlx4_en_ptp_overflow_check(struct mlx4_en_dev *mdev)
> -{
> -	bool timeout = time_is_before_jiffies(mdev->last_overflow_check +
> -					      mdev->overflow_period);
> +	/* Configure the PHC */
> +	mdev->ptp_clock_info = mlx4_en_ptp_clock_info;
> +	snprintf(mdev->ptp_clock_info.name, 16, "mlx4 ptp");
>  
> -	if (timeout) {
> -		timecounter_read(&mdev->clock);
> -		mdev->last_overflow_check = jiffies;
> +	mdev->ptp_clock = ptp_clock_register(&mdev->ptp_clock_info,
> +					     &mdev->pdev->dev);
> +	if (IS_ERR(mdev->ptp_clock)) {
> +		mdev->ptp_clock = NULL;
> +		mlx4_err(mdev, "ptp_clock_register failed\n");
> +	} else {
> +		mlx4_info(mdev, "registered PHC clock\n");
>  	}
> +
>  }
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
> index 0596f9f..3e8d336 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c
> @@ -1193,6 +1193,9 @@ static int mlx4_en_get_ts_info(struct net_device *dev,
>  		info->rx_filters =
>  			(1 << HWTSTAMP_FILTER_NONE) |
>  			(1 << HWTSTAMP_FILTER_ALL);
> +
> +		if (mdev->ptp_clock)
> +			info->phc_index = ptp_clock_index(mdev->ptp_clock);
>  	}
>  
>  	return ret;
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_main.c b/drivers/net/ethernet/mellanox/mlx4/en_main.c
> index 725a4e1..d357bf5 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_main.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_main.c
> @@ -199,6 +199,9 @@ static void mlx4_en_remove(struct mlx4_dev *dev, void *endev_ptr)
>  		if (mdev->pndev[i])
>  			mlx4_en_destroy_netdev(mdev->pndev[i]);
>  
> +	if (mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_TS)
> +		mlx4_en_remove_timestamp(mdev);
> +
>  	flush_workqueue(mdev->workqueue);
>  	destroy_workqueue(mdev->workqueue);
>  	(void) mlx4_mr_free(dev, &mdev->mr);
> diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
> index 123714c..298ce22 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
> +++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
> @@ -45,6 +45,7 @@
>  #include <linux/dcbnl.h>
>  #endif
>  #include <linux/cpu_rmap.h>
> +#include <linux/ptp_clock_kernel.h>
>  
>  #include <linux/mlx4/device.h>
>  #include <linux/mlx4/qp.h>
> @@ -375,10 +376,14 @@ struct mlx4_en_dev {
>  	u32                     priv_pdn;
>  	spinlock_t              uar_lock;
>  	u8			mac_removed[MLX4_MAX_PORTS + 1];
> +	rwlock_t		clock_lock;
> +	u32			nominal_c_mult;
>  	struct cyclecounter	cycles;
>  	struct timecounter	clock;
>  	unsigned long		last_overflow_check;
>  	unsigned long		overflow_period;
> +	struct ptp_clock	*ptp_clock;
> +	struct ptp_clock_info	ptp_clock_info;
>  };
>  
>  
> @@ -790,6 +795,7 @@ void mlx4_en_fill_hwtstamps(struct mlx4_en_dev *mdev,
>  			    struct skb_shared_hwtstamps *hwts,
>  			    u64 timestamp);
>  void mlx4_en_init_timestamp(struct mlx4_en_dev *mdev);
> +void mlx4_en_remove_timestamp(struct mlx4_en_dev *mdev);
>  int mlx4_en_timestamp_config(struct net_device *dev,
>  			     int tx_type,
>  			     int rx_filter);
> -- 
> 1.7.7.6
> 
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
Acked-By: Hadar Hen Zion <hadarh@mellanox.com>

Re: mlx4_en: Add PTP hardware clock

[David Miller]

From: Hadar Hen-Zion <hadarh@dev.mellanox.co.il>
Date: Wed, 1 Jan 2014 10:50:13 +0200

> On 31/12/13 11:39 -0600, Shawn Bohrer wrote:
 ...
> Acked-By: Hadar Hen Zion <hadarh@mellanox.com>

Please do not quote an entire large patch just to add your ACK,
quoting just the commit message is more than sufficient.

Quoting the entire patch wastes both bandwidth and reviewer time
because people have to scroll the entire patch again just to see
if you had some other feedback other than your simple ACK.

Re: [PATCH net-next v4 1/2] mlx4_en: Add PTP hardware clock

[Richard Cochran]

On Tue, Dec 31, 2013 at 11:39:39AM -0600, Shawn Bohrer wrote:
> From: Shawn Bohrer <sbohrer@rgmadvisors.com>
> 
> This adds a PHC to the mlx4_en driver. We 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.
> 
> This driver has been tested with both Documentation/ptp/testptp and the
> linuxptp project (http://linuxptp.sourceforge.net/) on a Mellanox
> ConnectX-3 card.
> 
> Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
> ---
>  drivers/net/ethernet/mellanox/mlx4/en_clock.c   |  194 ++++++++++++++++++++++-
>  drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |    3 +
>  drivers/net/ethernet/mellanox/mlx4/en_main.c    |    3 +
>  drivers/net/ethernet/mellanox/mlx4/mlx4_en.h    |    6 +
>  4 files changed, 198 insertions(+), 8 deletions(-)

Acked-by: Richard Cochran <richardcochran@gmail.com>

[PATCH net-next v4 2/2] mlx4_en: Only cycle port if HW timestamp config changes

[Shawn Bohrer]

From: Shawn Bohrer <sbohrer@rgmadvisors.com>

If the hwtstamp_config matches what is currently set for the device then
simply return.  Without this change any program that tries to enable
hardware timestamps will cause the link to cycle even if hardware
timstamps were already enabled.

Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_clock.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
index 30712b3..abaf6bb 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
@@ -42,6 +42,10 @@ int mlx4_en_timestamp_config(struct net_device *dev, int tx_type, int rx_filter)
 	int port_up = 0;
 	int err = 0;
 
+	if (priv->hwtstamp_config.tx_type == tx_type &&
+	    priv->hwtstamp_config.rx_filter == rx_filter)
+		return 0;
+
 	mutex_lock(&mdev->state_lock);
 	if (priv->port_up) {
 		port_up = 1;
-- 
1.7.7.6

Re: mlx4_en: Only cycle port if HW timestamp config changes

[Hadar Hen-Zion]

On 31/12/13 11:39 -0600, Shawn Bohrer wrote:
> From: Shawn Bohrer <sbohrer@rgmadvisors.com>
> 
> If the hwtstamp_config matches what is currently set for the device then
> simply return.  Without this change any program that tries to enable
> hardware timestamps will cause the link to cycle even if hardware
> timstamps were already enabled.
> 
> Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
> ---
>  drivers/net/ethernet/mellanox/mlx4/en_clock.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> index 30712b3..abaf6bb 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
> @@ -42,6 +42,10 @@ int mlx4_en_timestamp_config(struct net_device *dev, int tx_type, int rx_filter)
>  	int port_up = 0;
>  	int err = 0;
>  
> +	if (priv->hwtstamp_config.tx_type == tx_type &&
> +	    priv->hwtstamp_config.rx_filter == rx_filter)
> +		return 0;
> +
>  	mutex_lock(&mdev->state_lock);
>  	if (priv->port_up) {
>  		port_up = 1;
> -- 
> 1.7.7.6
> 
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
Acked-By: Hadar Hen Zion <hadarh@mellanox.com>

Re: [PATCH net-next v4 2/2] mlx4_en: Only cycle port if HW timestamp config changes

[Richard Cochran]

On Tue, Dec 31, 2013 at 11:39:40AM -0600, Shawn Bohrer wrote:
> From: Shawn Bohrer <sbohrer@rgmadvisors.com>
> 
> If the hwtstamp_config matches what is currently set for the device then
> simply return.  Without this change any program that tries to enable
> hardware timestamps will cause the link to cycle even if hardware
> timstamps were already enabled.
> 
> Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
> ---
>  drivers/net/ethernet/mellanox/mlx4/en_clock.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)

Acked-by: Richard Cochran <richardcochran@gmail.com>

Re: [PATCH net-next v4 0/2] mlx4_en: Add PTP support

[David Miller]

From: Shawn Bohrer <shawn.bohrer@gmail.com>
Date: Tue, 31 Dec 2013 11:39:38 -0600

> This adds support to the mlx4_en driver to support running a PTP client
> with hardware timestamp support.  It also allows synchronization of the
> hardware timestamped packets with the system clock.

Both patches applied.