ice_ptp_adj_clock(9)

💅 ice_ptp_adj_clock(9) — like, the PHC clock adjustment one

okay so bestie, welcome to the ice_ptp_adj_clock(9) page from the Kernel API Manual ✨ this is the little gremlin that nudges your PHC clock time atomically, and honestly? she ate. let me walk you through it 🫶

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✨ NAME ✨

ice_ptp_adj_clock — adjust PHC clock time atomically 💖

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🎀 SYNOPSIS 🎀

int ice_ptp_adj_clock (struct ice_hw *hw , s32 adj );

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🦋 ARGUMENTS 🦋

• hw — pointer to the HW struct, like, the whole hardware vibe check in struct form 👑
• adj — the adjustment in nanoseconds, which is s32 so yes it can be negative, we love a signed queen 💅

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🌸 DESCRIPTION 🌸

So what she does is perform an atomic adjustment of the PHC time by the specified number of nanoseconds. Atomic, meaning it all goes down together, no half-applied chaos, no cap 🔥

This is not a one-step slay, though. It requires a three-step process, and the steps matter:

1. Write the adjustment to the source timer shadow registers ✍️
2. Write the adjustment to the PHY timer shadow registers ✍️
3. Issue an ICE_PTP_ADJ_TIME timer command to synchronously apply the adjustment to both the source and port timers at the next clock cycle 🕐

The way that last step is *synchronous*… she waits for the next clock cycle so both timers move together. main character energy, honestly. periodt.

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🧚 SEE ALSO 🧚

First off, the kernel file this lives in: ./drivers/net/ethernet/intel/ice/ice_ptp_hw.c 📁 and then, okay, deep breath, because the see-also list is iconic and also lowkey enormous — every single one of these is here, no skipping:

ice_get_ptp_src_clock_index(9), ice_ptp_read_src_incval(9),
ice_ptp_tmr_cmd_to_src_reg(9), ice_ptp_tmr_cmd_to_port_reg(9),
ice_ptp_src_cmd(9), ice_ptp_exec_tmr_cmd(9), ice_ptp_cfg_sync_delay(9),
ice_ptp_init_phc_e825c(9), ice_ptp_get_dest_dev_e825(9),
ice_write_phy_eth56g(9), ice_read_phy_eth56g(9),
ice_get_serdes_ref_sel_e825c(9), ice_phy_res_address_eth56g(9),
ice_write_port_eth56g(9), ice_read_port_eth56g(9),
ice_write_ptp_reg_eth56g(9), ice_write_mac_reg_eth56g(9),
ice_write_xpcs_reg_eth56g(9), ice_read_ptp_reg_eth56g(9),
ice_read_mac_reg_eth56g(9), ice_read_gpcs_reg_eth56g(9),
ice_read_port_mem_eth56g(9), ice_write_port_mem_eth56g(9),
ice_write_quad_ptp_reg_eth56g(9), ice_read_quad_ptp_reg_eth56g(9),
ice_is_64b_phy_reg_eth56g(9), ice_is_40b_phy_reg_eth56g(9),
ice_read_64b_phy_reg_eth56g(9), ice_read_64b_ptp_reg_eth56g(9),
ice_write_40b_phy_reg_eth56g(9), ice_write_40b_ptp_reg_eth56g(9),
ice_write_64b_phy_reg_eth56g(9), ice_write_64b_ptp_reg_eth56g(9),
ice_read_ptp_tstamp_eth56g(9), ice_clear_ptp_tstamp_eth56g(9),
ice_ptp_reset_ts_memory_eth56g(9), ice_ptp_prep_port_time_eth56g(9),
ice_ptp_prep_phy_time_eth56g(9), ice_ptp_prep_port_adj_eth56g(9),
ice_ptp_prep_phy_adj_eth56g(9), ice_ptp_prep_phy_incval_eth56g(9),
ice_ptp_read_port_capture_eth56g(9), ice_ptp_write_port_cmd_eth56g(9),
ice_phy_get_speed_eth56g(9), ice_phy_cfg_parpcs_eth56g(9),
ice_phy_cfg_ptp_1step_eth56g(9), mul_u32_u32_fx_q9(9),
add_u32_u32_fx(9), ice_ptp_calc_bitslip_eth56g(9),
ice_ptp_calc_deskew_eth56g(9), ice_phy_set_offsets_eth56g(9),
ice_phy_cfg_mac_eth56g(9), ice_phy_cfg_intr_eth56g(9),
ice_read_phy_and_phc_time_eth56g(9), ice_sync_phy_timer_eth56g(9),
ice_stop_phy_timer_eth56g(9), ice_start_phy_timer_eth56g(9),
ice_check_phy_tx_tstamp_ready_eth56g(9),
ice_ptp_read_tx_hwtstamp_status_eth56g(9),
ice_ptp_phy_soft_reset_eth56g(9), ice_get_phy_tx_tstamp_ready_eth56g(9),
ice_ptp_init_phy_e825(9), ice_fill_phy_msg_e82x(9),
ice_is_64b_phy_reg_e82x(9), ice_is_40b_phy_reg_e82x(9),
ice_read_phy_reg_e82x(9), ice_read_64b_phy_reg_e82x(9),
ice_write_phy_reg_e82x(9), ice_write_40b_phy_reg_e82x(9),
ice_write_64b_phy_reg_e82x(9), ice_fill_quad_msg_e82x(9),
ice_read_quad_reg_e82x(9), ice_write_quad_reg_e82x(9),
ice_read_phy_tstamp_e82x(9), ice_clear_phy_tstamp_e82x(9),
ice_ptp_reset_ts_memory_quad_e82x(9), ice_ptp_reset_ts_memory_e82x(9),
ice_ptp_set_vernier_wl(9), ice_ptp_init_phc_e82x(9),
ice_ptp_prep_phy_time_e82x(9), ice_ptp_prep_port_adj_e82x(9),
ice_ptp_prep_phy_adj_e82x(9), ice_ptp_prep_phy_incval_e82x(9),
ice_ptp_read_port_capture(9), ice_ptp_write_port_cmd_e82x(9),
ice_phy_get_speed_and_fec_e82x(9), ice_phy_cfg_lane_e82x(9),
ice_phy_cfg_uix_e82x(9), ice_phy_cfg_parpcs_e82x(9),
ice_calc_fixed_tx_offset_e82x(9), ice_phy_cfg_tx_offset_e82x(9),
ice_phy_calc_pmd_adj_e82x(9), ice_calc_fixed_rx_offset_e82x(9),
ice_phy_cfg_rx_offset_e82x(9), ice_ptp_clear_phy_offset_ready_e82x(9),
ice_read_phy_and_phc_time_e82x(9), ice_sync_phy_timer_e82x(9),
ice_stop_phy_timer_e82x(9), ice_start_phy_timer_e82x(9),
ice_get_phy_tx_tstamp_ready_e82x(9),
ice_check_phy_tx_tstamp_ready_e82x(9), ice_phy_cfg_intr_e82x(9),
ice_ptp_init_phy_e82x(9), ice_read_phy_reg_e810(9),
ice_write_phy_reg_e810(9), ice_read_phy_tstamp_ll_e810(9),
ice_read_phy_tstamp_sbq_e810(9), ice_read_phy_tstamp_e810(9),
ice_clear_phy_tstamp_e810(9), ice_ptp_init_phc_e810(9),
ice_ptp_prep_phy_time_e810(9), ice_ptp_prep_phy_adj_ll_e810(9),
ice_ptp_prep_phy_adj_e810(9), ice_ptp_prep_phy_incval_ll_e810(9),
ice_ptp_prep_phy_incval_e810(9), ice_ptp_port_cmd_e810(9),
ice_get_phy_tx_tstamp_ready_e810(9),
ice_check_phy_tx_tstamp_ready_e810(9), ice_read_sma_ctrl(9),
ice_write_sma_ctrl(9), ice_ptp_read_sdp_ac(9), ice_ptp_init_phy_e810(9),
ice_ptp_init_phc_e830(9), ice_ptp_write_direct_incval_e830(9),
ice_ptp_write_direct_phc_time_e830(9), ice_ptp_port_cmd_e830(9),
ice_read_phy_tstamp_e830(9), ice_get_phy_tx_tstamp_ready_e830(9),
ice_check_phy_tx_tstamp_ready_e830(9), ice_ptp_init_phy_e830(9),
ice_ptp_lock(9), ice_ptp_unlock(9), ice_ptp_init_hw(9),
ice_ptp_write_port_cmd(9), ice_ptp_one_port_cmd(9), ice_ptp_port_cmd(9),
ice_ptp_tmr_cmd(9), ice_ptp_init_time(9), ice_ptp_write_incval(9),
ice_ptp_write_incval_locked(9), ice_read_phy_tstamp(9),
ice_clear_phy_tstamp(9), ice_get_pf_c827_idx(9),
ice_ptp_reset_ts_memory(9), ice_ptp_init_phc(9),
ice_get_phy_tx_tstamp_ready(9), ice_check_phy_tx_tstamp_ready(9),
ice_cgu_get_pin_desc_e823(9), ice_cgu_get_pin_desc(9),
ice_cgu_get_num_pins(9), ice_cgu_get_pin_type(9),
ice_cgu_get_pin_freq_supp(9), ice_cgu_get_pin_name(9),
ice_get_cgu_state(9), ice_get_cgu_rclk_pin_info(9),
ice_cgu_get_output_pin_state_caps(9)

like… the way she links to half the driver 💀 but we respect it, iykyk 🐝

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that's the whole page bestie, no crumbs left 🍓 this legendary text comes from ./drivers/net/ethernet/intel/ice, dated October 2026, and it answers to the name ice_ptp_adj_clock(9) — mwah, bye 💜🦋