STRUCT PHY_MSE_SNAPSHOT(9)

🦋 struct phy_mse_snapshot(9) — Kernel API Manual 🦋

okay bestie, this page is literally about a struct that holds your Mean Square Error diagnostics snapshot, and it’s lowkey important if you’re poking at PHY stuff 💅

🎀 NAME 🎀

struct phy_mse_snapshot — a snapshot of Mean Square Error (MSE) diagnostics ✨

✨ SYNOPSIS ✨

here’s the whole struct, no edits, no vibes-only summaries:

struct phy_mse_snapshot {
           u64 average_mse;
           u64 peak_mse;
           u64 worst_peak_mse;
        };

💖 Members 💖

• average_mse — the average MSE value over the measurement window. OPEN Alliance references MSE as a DCQ metric; recommends 2^16 symbols and 0..511 scaling. Exact scale and refresh are vendor-specific. (100BASE-T1 TC1 v1.0 6.1.1; 1000BASE-T1 TC12 v2.2 6.1.1).
• peak_mse — the peak MSE value observed within the measurement window. For 100BASE-T1, "pMSE" is optional and may be implemented via a sliding 128-symbol window with periodic capture; not standardized for 1000BASE-T1. (100BASE-T1 TC1 v1.0 6.1.3, Table "DCQ.peakMSE").
• worst_peak_mse — a latched high-water mark of the peak MSE since last read (read-to-clear if implemented). OPEN Alliance shows a latched "worst case peak MSE" for 100BASE-T1 pMSE; availability/semantics outside that are vendor-specific. (100BASE-T1 TC1 v1.0 6.1.3, DCQ.peakMSE high byte; 1000BASE-T1 TC12 v2.2 treats DCQ details as vendor-specific.)

🌈 Description 🌈

Holds a set of MSE diagnostic values that were all captured from a single measurement window. cute and coherent like that 🫶

Values are raw, device-scaled and not normalized. Use struct phy_mse_capability to interpret the scale and sampling window. periodt 💅

👑 SEE ALSO 👑

Kernel file ./include/linux/phy.h — plus the whole bestie squad right here:

• enum phy_interface_t(9)
• phy_modes(9)
• rgmii_clock(9)
• struct mdio_bus_stats(9)
• struct mii_bus(9)
• mdiobus_alloc(9)
• enum phy_state(9)
• struct phy_c45_device_ids(9)
• struct phy_oatc14_sqi_capability(9)
• struct phy_device(9)
• struct phy_tdr_config(9)
• enum link_inband_signalling(9)
• struct phy_plca_cfg(9)
• struct phy_plca_status(9)
• struct phy_led(9)
• struct phy_mse_capability(9)
• struct phy_driver(9)
• phy_id_compare(9)
• phy_id_compare_vendor(9)
• phy_id_compare_model(9)
• phydev_id_compare(9)
• phy_is_started(9)
• phy_driver_is_genphy(9)
• phy_disable_eee_mode(9)
• phy_can_wakeup(9)
• phy_may_wakeup(9)
• phy_read(9)
• __phy_read(9)
• phy_write(9)
• __phy_write(9)
• __phy_modify_changed(9)
• phy_read_mmd_poll_timeout(9)
• __phy_set_bits(9)
• __phy_clear_bits(9)
• phy_set_bits(9)
• phy_clear_bits(9)
• __phy_set_bits_mmd(9)
• __phy_clear_bits_mmd(9)
• phy_set_bits_mmd(9)
• phy_clear_bits_mmd(9)
• phy_interrupt_is_valid(9)
• phy_polling_mode(9)
• phy_has_hwtstamp(9)
• phy_has_rxtstamp(9)
• phy_has_tsinfo(9)
• phy_has_txtstamp(9)
• phy_is_default_hwtstamp(9)
• phy_on_sfp(9)
• phy_interface_mode_is_rgmii(9)
• phy_interface_mode_is_8023z(9)
• phy_interface_is_rgmii(9)
• phy_is_pseudo_fixed_link(9)
• phy_module_driver(9)

okay that’s the whole page, bestie 💅 source/version is ./include/linux, date is October 2026, and the main character is literally struct phy_mse_snapshot(9) 🫶✨