From: Carolina Jubran <cjubran@nvidia.com>
Implement the getcyclesx64 and getcrosscycles callbacks in ptp_info to
expose the device’s raw free-running counter.
Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
.../ethernet/mellanox/mlx5/core/lib/clock.c | 74 ++++++++++++++++++-
1 file changed, 73 insertions(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
index b1e2deeefc0c..2f75726674a9 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
@@ -306,6 +306,23 @@ static int mlx5_mtctr_syncdevicetime(ktime_t *device_time,
return 0;
}
+static int
+mlx5_mtctr_syncdevicecyclestime(ktime_t *device_time,
+ struct system_counterval_t *sys_counterval,
+ void *ctx)
+{
+ struct mlx5_core_dev *mdev = ctx;
+ u64 device;
+ int err;
+
+ err = mlx5_mtctr_read(mdev, false, sys_counterval, &device);
+ if (err)
+ return err;
+ *device_time = ns_to_ktime(device);
+
+ return 0;
+}
+
static int mlx5_ptp_getcrosststamp(struct ptp_clock_info *ptp,
struct system_device_crosststamp *cts)
{
@@ -330,6 +347,32 @@ static int mlx5_ptp_getcrosststamp(struct ptp_clock_info *ptp,
mlx5_clock_unlock(clock);
return err;
}
+
+static int mlx5_ptp_getcrosscycles(struct ptp_clock_info *ptp,
+ struct system_device_crosststamp *cts)
+{
+ struct mlx5_clock *clock =
+ container_of(ptp, struct mlx5_clock, ptp_info);
+ struct system_time_snapshot history_begin = {0};
+ struct mlx5_core_dev *mdev;
+ int err;
+
+ mlx5_clock_lock(clock);
+ mdev = mlx5_clock_mdev_get(clock);
+
+ if (!mlx5_is_ptm_source_time_available(mdev)) {
+ err = -EBUSY;
+ goto unlock;
+ }
+
+ ktime_get_snapshot(&history_begin);
+
+ err = get_device_system_crosststamp(mlx5_mtctr_syncdevicecyclestime,
+ mdev, &history_begin, cts);
+unlock:
+ mlx5_clock_unlock(clock);
+ return err;
+}
#endif /* CONFIG_X86 */
static u64 mlx5_read_time(struct mlx5_core_dev *dev,
@@ -528,6 +571,24 @@ static int mlx5_ptp_gettimex(struct ptp_clock_info *ptp, struct timespec64 *ts,
return 0;
}
+static int mlx5_ptp_getcyclesx(struct ptp_clock_info *ptp,
+ struct timespec64 *ts,
+ struct ptp_system_timestamp *sts)
+{
+ struct mlx5_clock *clock = container_of(ptp, struct mlx5_clock,
+ ptp_info);
+ struct mlx5_core_dev *mdev;
+ u64 cycles;
+
+ mlx5_clock_lock(clock);
+ mdev = mlx5_clock_mdev_get(clock);
+
+ cycles = mlx5_read_time(mdev, sts, false);
+ *ts = ns_to_timespec64(cycles);
+ mlx5_clock_unlock(clock);
+ return 0;
+}
+
static int mlx5_ptp_adjtime_real_time(struct mlx5_core_dev *mdev, s64 delta)
{
u32 in[MLX5_ST_SZ_DW(mtutc_reg)] = {};
@@ -1244,6 +1305,7 @@ static void mlx5_init_timer_max_freq_adjustment(struct mlx5_core_dev *mdev)
static void mlx5_init_timer_clock(struct mlx5_core_dev *mdev)
{
struct mlx5_clock *clock = mdev->clock;
+ bool expose_cycles;
/* Configure the PHC */
clock->ptp_info = mlx5_ptp_clock_info;
@@ -1251,12 +1313,22 @@ static void mlx5_init_timer_clock(struct mlx5_core_dev *mdev)
if (MLX5_CAP_MCAM_REG(mdev, mtutc))
mlx5_init_timer_max_freq_adjustment(mdev);
+ expose_cycles = !MLX5_CAP_GEN(mdev, disciplined_fr_counter) ||
+ !mlx5_real_time_mode(mdev);
+
#ifdef CONFIG_X86
if (MLX5_CAP_MCAM_REG3(mdev, mtptm) &&
- MLX5_CAP_MCAM_REG3(mdev, mtctr) && boot_cpu_has(X86_FEATURE_ART))
+ MLX5_CAP_MCAM_REG3(mdev, mtctr) && boot_cpu_has(X86_FEATURE_ART)) {
clock->ptp_info.getcrosststamp = mlx5_ptp_getcrosststamp;
+ if (expose_cycles)
+ clock->ptp_info.getcrosscycles =
+ mlx5_ptp_getcrosscycles;
+ }
#endif /* CONFIG_X86 */
+ if (expose_cycles)
+ clock->ptp_info.getcyclesx64 = mlx5_ptp_getcyclesx;
+
mlx5_timecounter_init(mdev);
mlx5_init_clock_info(mdev);
mlx5_init_overflow_period(mdev);
--
2.31.1
On 7/15/25 7:15 AM, Tariq Toukan wrote:
> From: Carolina Jubran <cjubran@nvidia.com>
>
> Implement the getcyclesx64 and getcrosscycles callbacks in ptp_info to
> expose the device’s raw free-running counter.
>
> Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
> Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
> ---
> .../ethernet/mellanox/mlx5/core/lib/clock.c | 74 ++++++++++++++++++-
> 1 file changed, 73 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
> index b1e2deeefc0c..2f75726674a9 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
> @@ -306,6 +306,23 @@ static int mlx5_mtctr_syncdevicetime(ktime_t *device_time,
> return 0;
> }
>
> +static int
> +mlx5_mtctr_syncdevicecyclestime(ktime_t *device_time,
> + struct system_counterval_t *sys_counterval,
> + void *ctx)
> +{
> + struct mlx5_core_dev *mdev = ctx;
> + u64 device;
> + int err;
> +
> + err = mlx5_mtctr_read(mdev, false, sys_counterval, &device);
> + if (err)
> + return err;
> + *device_time = ns_to_ktime(device);
If the goal is providing a raw cycle counter, why still using a timespec
to the user space? A plain u64 would possibly be less ambiguous.
/P
On 17/07/2025 13:55, Paolo Abeni wrote:
> On 7/15/25 7:15 AM, Tariq Toukan wrote:
>> From: Carolina Jubran <cjubran@nvidia.com>
>>
>> Implement the getcyclesx64 and getcrosscycles callbacks in ptp_info to
>> expose the device’s raw free-running counter.
>>
>> Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
>> Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
>> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
>> ---
>> .../ethernet/mellanox/mlx5/core/lib/clock.c | 74 ++++++++++++++++++-
>> 1 file changed, 73 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
>> index b1e2deeefc0c..2f75726674a9 100644
>> --- a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
>> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
>> @@ -306,6 +306,23 @@ static int mlx5_mtctr_syncdevicetime(ktime_t *device_time,
>> return 0;
>> }
>>
>> +static int
>> +mlx5_mtctr_syncdevicecyclestime(ktime_t *device_time,
>> + struct system_counterval_t *sys_counterval,
>> + void *ctx)
>> +{
>> + struct mlx5_core_dev *mdev = ctx;
>> + u64 device;
>> + int err;
>> +
>> + err = mlx5_mtctr_read(mdev, false, sys_counterval, &device);
>> + if (err)
>> + return err;
>> + *device_time = ns_to_ktime(device);
>
> If the goal is providing a raw cycle counter, why still using a timespec
> to the user space? A plain u64 would possibly be less ambiguous.
>
> /P
>
getcycles64 and getcrosscycles already return the cycle counter in a
timespec64/ktime format, so I kept the new ioctls consistent with them.
On 7/17/25 5:56 PM, Carolina Jubran wrote:
> On 17/07/2025 13:55, Paolo Abeni wrote:
>> On 7/15/25 7:15 AM, Tariq Toukan wrote:
>>> From: Carolina Jubran <cjubran@nvidia.com>
>>>
>>> Implement the getcyclesx64 and getcrosscycles callbacks in ptp_info to
>>> expose the device’s raw free-running counter.
>>>
>>> Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
>>> Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
>>> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
>>> ---
>>> .../ethernet/mellanox/mlx5/core/lib/clock.c | 74 ++++++++++++++++++-
>>> 1 file changed, 73 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
>>> index b1e2deeefc0c..2f75726674a9 100644
>>> --- a/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
>>> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/clock.c
>>> @@ -306,6 +306,23 @@ static int mlx5_mtctr_syncdevicetime(ktime_t *device_time,
>>> return 0;
>>> }
>>>
>>> +static int
>>> +mlx5_mtctr_syncdevicecyclestime(ktime_t *device_time,
>>> + struct system_counterval_t *sys_counterval,
>>> + void *ctx)
>>> +{
>>> + struct mlx5_core_dev *mdev = ctx;
>>> + u64 device;
>>> + int err;
>>> +
>>> + err = mlx5_mtctr_read(mdev, false, sys_counterval, &device);
>>> + if (err)
>>> + return err;
>>> + *device_time = ns_to_ktime(device);
>>
>> If the goal is providing a raw cycle counter, why still using a timespec
>> to the user space? A plain u64 would possibly be less ambiguous.
>>
>> /P
>>
>
> getcycles64 and getcrosscycles already return the cycle counter in a
> timespec64/ktime format, so I kept the new ioctls consistent with them.
Ah, sorry I missed that context. Looks good to me than.
Thanks,
Paolo
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