STRUCT DPNI_SINGLE_STEP_CFG(9)

💅 struct dpni_single_step_cfg(9) — the Kernel API Manual, bestie edition 🕰️✨

Okay so this is a page from the Kernel API Manual (section 9, the kernel-API girlies know 😌), and it's all about struct dpni_single_step_cfg — literally the struct you use to configure single step PTP, which is IEEE 1588. Clock girlies, this one's for you 🎀

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✨ SYNOPSIS ✨

Here's the whole struct, exactly as it lives, no cap:

struct dpni_single_step_cfg {
    u8 en;
    u8 ch_update;
    u16 offset;
    u32 peer_delay;
    u32 ptp_onestep_reg_base;
 };

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🦋 Members 🦋

Let's meet the cast, one field at a time — every single one of them matters, so no skipping 🙏

• en — turns single step PTP on. But listen: when it's enabled, the PTPv1 functionality will not work, so that's a whole trade-off bestie 💀. And if this field is zero? Then offset and ch_update just get ignored, like they weren't even invited to the party 🙈
• ch_update — when this is set, the UDP checksum gets updated inside the packet. That's it, that's the vibe ✨
• offset — the start offset from the beginning of the frame where the timestamp field is found. It's giving "where's the timestamp" scavenger hunt 🔍. The offset must respect all MAC headers, VLAN tags and other protocol headers — like, all of them, don't skip any or it gets mad 😤
• peer_delay — for peer-to-peer transparent clocks, you add this value to the correction field in addition to the transient time update. And the value expresses nanoseconds ⏱️ (nano girlies, precision icons 💅)
• ptp_onestep_reg_base — the 1588 SINGLE_STEP register base address 👑. This address is used to update directly the register contents, and here's the important bit: the user has to create an address mapping for it 🔥. You don't get it for free, you gotta set it up yourself fr fr.

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🌈 SEE ALSO 🌈

Kernel file: ./drivers/net/ethernet/freescale/dpaa2/dpni.h 📁

And the whole friend group, in order, all of them, because we don't leave anyone out 🫶:

DPNI_MAX_TC(9), DPNI_MAX_DPBP(9), DPNI_ALL_TCS(9), DPNI_ALL_TC_FLOWS(9), DPNI_NEW_FLOW_ID(9), DPNI_OPT_TX_FRM_RELEASE(9), DPNI_OPT_NO_MAC_FILTER(9), DPNI_OPT_HAS_POLICING(9), DPNI_OPT_SHARED_CONGESTION(9), DPNI_OPT_HAS_KEY_MASKING(9), DPNI_OPT_NO_FS(9), DPNI_OPT_SHARED_FS(9), struct dpni_pools_cfg(9), struct dpni_attr(9), DPNI_ERROR_EOFHE(9), DPNI_ERROR_FLE(9), DPNI_ERROR_FPE(9), DPNI_ERROR_PHE(9), DPNI_ERROR_L3CE(9), DPNI_ERROR_L4CE(9), enum dpni_error_action(9), struct dpni_error_cfg(9), DPNI_BUF_LAYOUT_OPT_TIMESTAMP(9), DPNI_BUF_LAYOUT_OPT_PARSER_RESULT(9), DPNI_BUF_LAYOUT_OPT_FRAME_STATUS(9), DPNI_BUF_LAYOUT_OPT_PRIVATE_DATA_SIZE(9), DPNI_BUF_LAYOUT_OPT_DATA_ALIGN(9), DPNI_BUF_LAYOUT_OPT_DATA_HEAD_ROOM(9), DPNI_BUF_LAYOUT_OPT_DATA_TAIL_ROOM(9), struct dpni_buffer_layout(9), enum dpni_queue_type(9), enum dpni_offload(9), union dpni_statistics(9), struct dpni_link_cfg(9), struct dpni_link_state(9), enum dpni_dist_mode(9), enum dpni_fs_miss_action(9), struct dpni_fs_tbl_cfg(9), struct dpni_rx_tc_dist_cfg(9), DPNI_FS_MISS_DROP(9), struct dpni_rx_dist_cfg(9), struct dpni_qos_tbl_cfg(9), enum dpni_dest(9), struct dpni_queue(9), struct dpni_queue_id(9), enum dpni_congestion_unit(9), enum dpni_congestion_point(9), struct dpni_dest_cfg(9), DPNI_CONG_OPT_FLOW_CONTROL(9), struct dpni_congestion_notification_cfg(9), struct dpni_taildrop(9), struct dpni_rule_cfg(9), DPNI_FS_OPT_DISCARD(9), DPNI_FS_OPT_SET_FLC(9), DPNI_FS_OPT_SET_STASH_CONTROL(9), struct dpni_fs_action_cfg(9), struct dpni_tx_shaping_cfg(9)

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💖 oh and a lil heads up: that SEE ALSO list is long long, but every single one of those pages is real and you should not skip them, iykyk

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Okay bye besties!! 👋 This page comes from ./drivers/net/ethernet/freesca... and it's dated October 2026, and the footer is literally just struct dpni_single_step_cfg(9) again — so consider this your cute sign-off, drink some water, and go configure your single step PTP 💜🧚🌸