Re: [PATCH v2] net/ice: fix incorrect reading of PHY timestamp

[Bruce Richardson <bruce.richardson@intel.com>]

On Wed, Oct 30, 2024 at 02:16:11AM +0000, Soumyadeep Hore wrote:
> In ICE PMD, previously the ready bitmap checking before reading
> PHY timestamp was not present. This caused incorrect Tx
> timestamping.
> 
> The ready bitmap checking is enabled and PHY timestamp is read once
> the ready bitmap gives positive value.
> 
> Fixes: 881169950d80 ("net/ice/base: implement initial PTP support for E830")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Soumyadeep Hore <soumyadeep.hore@intel.com>
> ---
> v2:
> - Addressed Bruce's comments
> ---
>  drivers/net/ice/ice_ethdev.c | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ice/ice_ethdev.c b/drivers/net/ice/ice_ethdev.c
> index 70298ac330..6d0d37b3a0 100644
> --- a/drivers/net/ice/ice_ethdev.c
> +++ b/drivers/net/ice/ice_ethdev.c
> @@ -6597,10 +6597,26 @@ ice_timesync_read_tx_timestamp(struct rte_eth_dev *dev,
>  	struct ice_hw *hw = ICE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
>  	struct ice_adapter *ad =
>  			ICE_DEV_PRIVATE_TO_ADAPTER(dev->data->dev_private);
> -	uint64_t ts_ns, tstamp;
> +	uint64_t ts_ns, tstamp, tstamp_ready = 0;
> +	uint64_t end_time;
>  	const uint64_t mask = 0xFFFFFFFF;
>  	int ret;
>  
> +	end_time = rte_get_timer_cycles() + rte_get_timer_hz();
> +

Patch code itself looks fine, but don't you think that 1sec is an
excessively long time to wait? Maybe do a V3 with a lower timeout
threshold.

/Bruce