STRUCT IWL_MAC_BEACON_CMD(9)

💖 struct iwl_mac_beacon_cmd(9) 💖

okay bestie, buckle up — this is a page straight out of the Kernel API Manual, and it's all about struct iwl_mac_beacon_cmd. it's the beacon template command with offloaded CSA, and honestly? she's iconic. let's get into it 🎀

✨ SYNOPSIS ✨

here's the whole struct, exactly as she lives in the kernel — no notes, no edits, just vibes:

struct iwl_mac_beacon_cmd {
    __le16 byte_cnt;
    __le16 flags;
    __le32 short_ssid;
    __le32 reserved;
    __le32 link_id;
    __le32 tim_idx;
    union {
      __le32 tim_size;
      __le32 btwt_offset;
    };
    __le32 ecsa_offset;
    __le32 csa_offset;
    struct ieee80211_hdr frame[];
};

like, look at that anonymous union just floating there. main character energy fr fr 💅

🦋 Members 🦋

okay so let's go field by field, because every single one of these matters, no cap:

• byte_cnt — the byte count of the beacon frame. that's it, that's the whole job 🍓
• flags — the least significant byte here is the rate code. the most significant byte is enum iwl_mac_beacon_flags. two jobs, one field, she contains multitudes ✨
• short_ssid — the Short SSID. literally, that's the description. short and sweet, we respect it 🫶
• reserved — reserved. it's reserved bestie, don't touch it 🙈
• link_id — the firmware id of the link that will use this beacon 👑
• tim_idx — the offset of the tim IE in the beacon 📍
• {unnamed_union} — anonymous. yes, that's really the whole description. she's mysterious, she's unnamed, she refuses to elaborate 💀
• tim_size — the length of the tim IE (version < 14). note the version gate, it's important 🧚
• btwt_offset — offset to the broadcast TWT IE if present (version >= 14). this is the other half of that anonymous union, so it's one or the other depending on version, iykyk 🌈
• ecsa_offset — offset to the ECSA IE if present 🌸
• csa_offset — offset to the CSA IE if present 🔥
• frame — the template of the beacon frame. it's a flexible array member (struct ieee80211_hdr frame[]), so she stretches to fit ⭐

lowkey reminder: tim_size and btwt_offset share that anonymous union — you get the tim IE length on version < 14, and the broadcast TWT IE offset on version >= 14. don't mix them up, bestie 😭

🌟 SEE ALSO 🌟

the whole friend group, and we're listing every single one because nobody gets left out 💜:

• Kernel file ./drivers/net/wireless/intel/iwlwifi/fw/api/tx.h
• enum iwl_tx_flags(9)
• enum iwl_tx_cmd_flags(9)
• enum iwl_tx_pm_timeouts(9)
• enum iwl_tx_cmd_sec_ctrl(9)
• enum iwl_tx_offload_assist_flags_pos(9)
• struct iwl_tx_cmd_v6_params(9)
• struct iwl_tx_cmd_v6(9)
• struct iwl_tx_cmd_v9(9)
• struct iwl_tx_cmd(9)
• struct agg_tx_status(9)
• struct iwl_tx_resp_v3(9)
• struct iwl_tx_resp(9)
• struct iwl_mvm_ba_notif(9)
• struct iwl_compressed_ba_tfd(9)
• struct iwl_compressed_ba_ratid(9)
• struct iwl_compressed_ba_notif(9)
• struct iwl_mac_beacon_cmd_v6(9)
• struct iwl_mac_beacon_cmd_v7(9)
• struct iwl_extended_beacon_notif_v5(9)
• struct iwl_extended_beacon_notif(9)
• enum iwl_dump_control(9)
• struct iwl_tx_path_flush_cmd_v1(9)
• struct iwl_tx_path_flush_cmd(9)
• struct iwl_flush_queue_info(9)
• struct iwl_tx_path_flush_cmd_rsp(9)
• struct iwl_scd_txq_cfg_cmd(9)
• struct iwl_scd_txq_cfg_rsp(9)

and that's the page, bestie!! 🎀 signed off from ./drivers/net/wireless/intel/i..., dated October 2026, and she's still out here being struct iwl_mac_beacon_cmd(9). go forth and beacon responsibly ✨💖🦋