Re: [PATCH v3 net-next 11/15] net: enetc: extract enetc_update_ptp_sync_msg() to handle PTP Sync packets

Frank Li
2025-08-12T15:52:55Z

On Tue, Aug 12, 2025 at 05:46:30PM +0800, Wei Fang wrote:
> Move PTP Sync packet processing from enetc_map_tx_buffs() to a new helper
> function enetc_update_ptp_sync_msg() to simplify the original function.
> Prepare for upcoming ENETC v4 one-step support.

Add "no functional change".

>
> Signed-off-by: Wei Fang <wei.fang@nxp.com>
>
> ---
> v2: no changes
> v3: Change the subject and improve the commit message
> ---
> drivers/net/ethernet/freescale/enetc/enetc.c | 129 ++++++++++--------
> .../net/ethernet/freescale/enetc/enetc_hw.h | 1 +
> 2 files changed, 71 insertions(+), 59 deletions(-)
>
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
> index 54ccd7c57961..ef002ed2fdb9 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc.c
> +++ b/drivers/net/ethernet/freescale/enetc/enetc.c
> @@ -221,12 +221,79 @@ static void enetc_unwind_tx_frame(struct enetc_bdr *tx_ring, int count, int i)
> }
> }
>
> +static u32 enetc_update_ptp_sync_msg(struct enetc_ndev_priv *priv,
> + struct sk_buff *skb)
> +{
> + struct enetc_skb_cb *enetc_cb = ENETC_SKB_CB(skb);
> + u16 tstamp_off = enetc_cb->origin_tstamp_off;
> + u16 corr_off = enetc_cb->correction_off;
> + struct enetc_si *si = priv->si;
> + struct enetc_hw *hw = &si->hw;
> + __be32 new_sec_l, new_nsec;
> + __be16 new_sec_h;
> + u32 lo, hi, nsec;
> + u8 *data;
> + u64 sec;
> + u32 val;
> +
> + lo = enetc_rd_hot(hw, ENETC_SICTR0);
> + hi = enetc_rd_hot(hw, ENETC_SICTR1);
> + sec = (u64)hi << 32 | lo;
> + nsec = do_div(sec, 1000000000);
> +
> + /* Update originTimestamp field of Sync packet
> + * - 48 bits seconds field
> + * - 32 bits nanseconds field
> + *
> + * In addition, the UDP checksum needs to be updated
> + * by software after updating originTimestamp field,
> + * otherwise the hardware will calculate the wrong
> + * checksum when updating the correction field and
> + * update it to the packet.
> + */
> +
> + data = skb_mac_header(skb);
> + new_sec_h = htons((sec >> 32) & 0xffff);
> + new_sec_l = htonl(sec & 0xffffffff);
> + new_nsec = htonl(nsec);
> + if (enetc_cb->udp) {
> + struct udphdr *uh = udp_hdr(skb);
> + __be32 old_sec_l, old_nsec;
> + __be16 old_sec_h;
> +
> + old_sec_h = *(__be16 *)(data + tstamp_off);
> + inet_proto_csum_replace2(&uh->check, skb, old_sec_h,
> + new_sec_h, false);
> +
> + old_sec_l = *(__be32 *)(data + tstamp_off + 2);
> + inet_proto_csum_replace4(&uh->check, skb, old_sec_l,
> + new_sec_l, false);
> +
> + old_nsec = *(__be32 *)(data + tstamp_off + 6);
> + inet_proto_csum_replace4(&uh->check, skb, old_nsec,
> + new_nsec, false);
> + }
> +
> + *(__be16 *)(data + tstamp_off) = new_sec_h;
> + *(__be32 *)(data + tstamp_off + 2) = new_sec_l;
> + *(__be32 *)(data + tstamp_off + 6) = new_nsec;
> +
> + /* Configure single-step register */
> + val = ENETC_PM0_SINGLE_STEP_EN;
> + val |= ENETC_SET_SINGLE_STEP_OFFSET(corr_off);
> + if (enetc_cb->udp)
> + val |= ENETC_PM0_SINGLE_STEP_CH;
> +
> + enetc_port_mac_wr(priv->si, ENETC_PM0_SINGLE_STEP, val);
> +
> + return lo & ENETC_TXBD_TSTAMP;
> +}
> +
> static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
> {
> bool do_vlan, do_onestep_tstamp = false, do_twostep_tstamp = false;
> struct enetc_ndev_priv *priv = netdev_priv(tx_ring->ndev);
> struct enetc_skb_cb *enetc_cb = ENETC_SKB_CB(skb);
> - struct enetc_hw *hw = &priv->si->hw;
> struct enetc_tx_swbd *tx_swbd;
> int len = skb_headlen(skb);
> union enetc_tx_bd temp_bd;
> @@ -326,67 +393,11 @@ static int enetc_map_tx_buffs(struct enetc_bdr *tx_ring, struct sk_buff *skb)
> }
>
> if (do_onestep_tstamp) {
> - u16 tstamp_off = enetc_cb->origin_tstamp_off;
> - u16 corr_off = enetc_cb->correction_off;
> - __be32 new_sec_l, new_nsec;
> - u32 lo, hi, nsec, val;
> - __be16 new_sec_h;
> - u8 *data;
> - u64 sec;
> -
> - lo = enetc_rd_hot(hw, ENETC_SICTR0);
> - hi = enetc_rd_hot(hw, ENETC_SICTR1);
> - sec = (u64)hi << 32 | lo;
> - nsec = do_div(sec, 1000000000);
> + u32 tstamp = enetc_update_ptp_sync_msg(priv, skb);
>
> /* Configure extension BD */
> - temp_bd.ext.tstamp = cpu_to_le32(lo & 0x3fffffff);
> + temp_bd.ext.tstamp = cpu_to_le32(tstamp);
> e_flags |= ENETC_TXBD_E_FLAGS_ONE_STEP_PTP;
> -
> - /* Update originTimestamp field of Sync packet
> - * - 48 bits seconds field
> - * - 32 bits nanseconds field
> - *
> - * In addition, the UDP checksum needs to be updated
> - * by software after updating originTimestamp field,
> - * otherwise the hardware will calculate the wrong
> - * checksum when updating the correction field and
> - * update it to the packet.
> - */
> - data = skb_mac_header(skb);
> - new_sec_h = htons((sec >> 32) & 0xffff);
> - new_sec_l = htonl(sec & 0xffffffff);
> - new_nsec = htonl(nsec);
> - if (enetc_cb->udp) {
> - struct udphdr *uh = udp_hdr(skb);
> - __be32 old_sec_l, old_nsec;
> - __be16 old_sec_h;
> -
> - old_sec_h = *(__be16 *)(data + tstamp_off);
> - inet_proto_csum_replace2(&uh->check, skb, old_sec_h,
> - new_sec_h, false);
> -
> - old_sec_l = *(__be32 *)(data + tstamp_off + 2);
> - inet_proto_csum_replace4(&uh->check, skb, old_sec_l,
> - new_sec_l, false);
> -
> - old_nsec = *(__be32 *)(data + tstamp_off + 6);
> - inet_proto_csum_replace4(&uh->check, skb, old_nsec,
> - new_nsec, false);
> - }
> -
> - *(__be16 *)(data + tstamp_off) = new_sec_h;
> - *(__be32 *)(data + tstamp_off + 2) = new_sec_l;
> - *(__be32 *)(data + tstamp_off + 6) = new_nsec;
> -
> - /* Configure single-step register */
> - val = ENETC_PM0_SINGLE_STEP_EN;
> - val |= ENETC_SET_SINGLE_STEP_OFFSET(corr_off);
> - if (enetc_cb->udp)
> - val |= ENETC_PM0_SINGLE_STEP_CH;
> -
> - enetc_port_mac_wr(priv->si, ENETC_PM0_SINGLE_STEP,
> - val);
> } else if (do_twostep_tstamp) {
> skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
> e_flags |= ENETC_TXBD_E_FLAGS_TWO_STEP_PTP;
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc_hw.h b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
> index 73763e8f4879..377c96325814 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc_hw.h
> +++ b/drivers/net/ethernet/freescale/enetc/enetc_hw.h
> @@ -614,6 +614,7 @@ enum enetc_txbd_flags {
> #define ENETC_TXBD_STATS_WIN BIT(7)
> #define ENETC_TXBD_TXSTART_MASK GENMASK(24, 0)
> #define ENETC_TXBD_FLAGS_OFFSET 24
> +#define ENETC_TXBD_TSTAMP GENMASK(29, 0)

Suppose this type patch no any addtional change to reduce review efforts.

Or you need say replace 0x3fffffff with ENETC_TXBD_TSTAMP.

Frank

>
> static inline __le32 enetc_txbd_set_tx_start(u64 tx_start, u8 flags)
> {
> --
> 2.34.1
>