> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf
> Of Mina Almasry
> Sent: Saturday, November 22, 2025 3:09 PM
> To: [email protected]; [email protected]; linux-
> [email protected]
> Cc: YiFei Zhu <[email protected]>; Alexei Starovoitov
> <[email protected]>; Daniel Borkmann <[email protected]>; David S.
> Miller <[email protected]>; Jakub Kicinski <[email protected]>; Jesper
> Dangaard Brouer <[email protected]>; John Fastabend
> <[email protected]>; Stanislav Fomichev <[email protected]>;
> Nguyen, Anthony L <[email protected]>; Kitszel, Przemyslaw
> <[email protected]>; Andrew Lunn <[email protected]>;
> Eric Dumazet <[email protected]>; Paolo Abeni <[email protected]>;
> Lobakin, Aleksander <[email protected]>; Richard Cochran
> <[email protected]>; [email protected]; Mina
> Almasry <[email protected]>
> Subject: [Intel-wired-lan] [PATCH net-next v1] idpf: export RX
> hardware timestamping information to XDP
>
> From: YiFei Zhu <[email protected]>
>
> The logic is similar to idpf_rx_hwtstamp, but the data is exported as
> a BPF kfunc instead of appended to an skb.
>
> A idpf_queue_has(PTP, rxq) condition is added to check the queue
> supports PTP similar to idpf_rx_process_skb_fields.
>
> Cc: [email protected]
>
> Signed-off-by: YiFei Zhu <[email protected]>
> Signed-off-by: Mina Almasry <[email protected]>
> ---
> drivers/net/ethernet/intel/idpf/xdp.c | 27
> +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/drivers/net/ethernet/intel/idpf/xdp.c
> b/drivers/net/ethernet/intel/idpf/xdp.c
> index 21ce25b0567f..850389ca66b6 100644
> --- a/drivers/net/ethernet/intel/idpf/xdp.c
> +++ b/drivers/net/ethernet/intel/idpf/xdp.c
> @@ -2,6 +2,7 @@
> /* Copyright (C) 2025 Intel Corporation */
>
> #include "idpf.h"
> +#include "idpf_ptp.h"
> #include "idpf_virtchnl.h"
> #include "xdp.h"
> #include "xsk.h"
> @@ -369,6 +370,31 @@ int idpf_xdp_xmit(struct net_device *dev, int n,
> struct xdp_frame **frames,
> idpf_xdp_tx_finalize);
> }
>
> +static int idpf_xdpmo_rx_timestamp(const struct xdp_md *ctx, u64
> +*timestamp) {
> + const struct virtchnl2_rx_flex_desc_adv_nic_3 *rx_desc;
> + const struct libeth_xdp_buff *xdp = (typeof(xdp))ctx;
> + const struct idpf_rx_queue *rxq;
> + u64 cached_time, ts_ns;
> + u32 ts_high;
> +
> + rx_desc = xdp->desc;
> + rxq = libeth_xdp_buff_to_rq(xdp, typeof(*rxq), xdp_rxq);
> +
> + if (!idpf_queue_has(PTP, rxq))
> + return -ENODATA;
> + if (!(rx_desc->ts_low & VIRTCHNL2_RX_FLEX_TSTAMP_VALID))
> + return -ENODATA;
RX flex desc fields are little‑endian.
You already convert ts_high with le32_to_cpu(), but test ts_low directly
against the mask.
On big‑endian this can misdetect the bit and spuriously return -ENODATA.
Please convert ts_low to host order before the bit test.
See existing IDPF/ICE patterns where descriptor words are
leXX_to_cpu()‑converted prior to FIELD_GET() / bit checks.
Also, per the XDP RX metadata kfunc docs, -ENODATA must reflect true absence of
per‑packet metadata; endianness‑correct testing is required to uphold the
semantic.
> +
> + cached_time = READ_ONCE(rxq->cached_phc_time);
> +
> + ts_high = le32_to_cpu(rx_desc->ts_high);
> + ts_ns = idpf_ptp_tstamp_extend_32b_to_64b(cached_time,
> ts_high);
> +
> + *timestamp = ts_ns;
> + return 0;
> +}
> +
> static int idpf_xdpmo_rx_hash(const struct xdp_md *ctx, u32 *hash,
> enum xdp_rss_hash_type *rss_type) { @@ -
> 392,6 +418,7 @@ static int idpf_xdpmo_rx_hash(const struct xdp_md
> *ctx, u32 *hash, }
>
> static const struct xdp_metadata_ops idpf_xdpmo = {
> + .xmo_rx_timestamp = idpf_xdpmo_rx_timestamp,
> .xmo_rx_hash = idpf_xdpmo_rx_hash,
> };
>
>
> base-commit: e05021a829b834fecbd42b173e55382416571b2c
> --
> 2.52.0.rc2.455.g230fcf2819-goog
