t4_bar2_sge_qregs(9)

🌸 t4_bar2_sge_qregs(9) — the Kernel API Manual glow-up ✨

okay so bestie, welcome to the <pink>Kernel API Manual</pink> entry for t4_bar2_sge_qregs — it's giving "small function, big doorbell energy," and honestly we're obsessed 💅

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✨ NAME ✨

t4_bar2_sge_qregs — return BAR2 SGE Queue register information 🎀

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🦋 SYNOPSIS 🦋

int t4_bar2_sge_qregs (struct adapter *adapter , unsigned int qid , enum
       t4_bar2_qtype qtype , int user , u64 *pbar2_qoffset , unsigned int
       *pbar2_qid );

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💖 ARGUMENTS 💖

• adapter — the adapter, aka the whole main character of this operation 🫶
• qid — the Queue ID, literally the queue's little name tag ✨
• qtype — the Ingress or Egress type for qid — pick a lane, bestie 🌈
• user — true if this request is for a user mode queue 👑
• pbar2_qoffset — the BAR2 Offset of the qid Registers 📍
• pbar2_qid — the BAR2 SGE Queue ID or 0 of qid — yes, 0 is a whole vibe here, iykyk 💀

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🔥 DESCRIPTION 🔥

So what it does: it returns the BAR2 SGE Queue Registers info associated with the indicated Absolute Queue ID. All of that comes back through the return value pointers, no cap 🎯 qtype should be T4_BAR2_QTYPE_EGRESS for Egress Queue and T4_BAR2_QTYPE_INGRESS for Ingress Queues — literally just pick the right one, it's not that deep 🦋

This may return an error which indicates that BAR2 SGE Queue registers aren't available 😭 If an error is not returned, then the following values are returned:

If the returned BAR2 Queue ID is 0, then BAR2 SGE registers which require the "Inferred Queue ID" ability may be used. E.g. the Write Combining Doorbell Buffer 🔔✨ If the BAR2 Queue ID is not 0, then these "Inferred Queue ID" register may not be used 🙈 — that's the whole rule, periodt.

💀 read that twice, bestie — the 0 vs not-0 thing is exactly the kind of detail that eats people alive in code review. the "Inferred Queue ID" registers only work when the returned BAR2 Queue ID is 0.

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🧚 SEE ALSO 🧚

Kernel file ./drivers/net/ethernet/chelsio/cxgb4/t4_hw.c — that's the mothership 🏠

and like, a whole friend group of functions, all of them, in order, no skips 💜:

t4_wait_op_done_val(9), t4_set_reg_field(9), t4_read_indirect(9), t4_write_indirect(9), t4_record_mbox(9), t4_wr_mbox_meat_timeout(9), t4_memory_rw_init(9), t4_memory_update_win(9), t4_memory_rw_residual(9), t4_memory_rw(9), t4_get_regs_len(9), t4_get_regs(9), t4_eeprom_ptov(9), t4_seeprom_wp(9), t4_get_raw_vpd_params(9), t4_get_vpd_params(9), t4_get_pfres(9), sf1_read(9), sf1_write(9), flash_wait_op(9), t4_read_flash(9), t4_write_flash(9), t4_get_fw_version(9), t4_get_bs_version(9), t4_get_tp_version(9), t4_get_exprom_version(9), t4_get_vpd_version(9), t4_get_scfg_version(9), t4_get_version_info(9), t4_dump_version_info(9), t4_check_fw_version(9), t4_flash_erase_sectors(9), t4_flash_cfg_addr(9), t4_load_fw(9), t4_phy_fw_ver(9), t4_load_phy_fw(9), t4_fwcache(9), fwcaps16_to_caps32(9), fwcaps32_to_caps16(9), t4_link_acaps(9), t4_link_l1cfg_core(9), t4_restart_aneg(9), t4_handle_intr_status(9), t4_slow_intr_handler(9), t4_intr_enable(9), t4_intr_disable(9), t4_config_rss_range(9), t4_config_glbl_rss(9), t4_config_vi_rss(9), t4_read_rss(9), t4_tp_fw_ldst_rw(9), t4_tp_indirect_rw(9), t4_tp_pio_read(9), t4_tp_pio_write(9), t4_tp_tm_pio_read(9), t4_tp_mib_read(9), t4_read_rss_key(9), t4_write_rss_key(9), t4_read_rss_pf_config(9), t4_read_rss_vf_config(9), t4_read_rss_pf_map(9), t4_read_rss_pf_mask(9), t4_tp_get_tcp_stats(9), t4_tp_get_err_stats(9), t4_tp_get_cpl_stats(9), t4_tp_get_rdma_stats(9), t4_get_fcoe_stats(9), t4_get_usm_stats(9), t4_read_mtu_tbl(9), t4_read_cong_tbl(9), t4_tp_wr_bits_indirect(9), init_cong_ctrl(9), t4_load_mtus(9), t4_get_chan_txrate(9), t4_set_trace_filter(9), t4_get_trace_filter(9), t4_pmtx_get_stats(9), t4_pmrx_get_stats(9), compute_mps_bg_map(9), t4_get_mps_bg_map(9), t4_get_tp_e2c_map(9), t4_get_tp_ch_map(9), t4_get_port_type_description(9), t4_get_port_stats_offset(9), t4_get_port_stats(9), t4_get_lb_stats(9), t4_mdio_rd(9), t4_mdio_wr(9), t4_sge_decode_idma_state(9), t4_sge_ctxt_flush(9), t4_read_sge_dbqtimers(9), t4_fw_hello(9), t4_fw_bye(9), t4_early_init(9), t4_fw_reset(9), t4_fw_halt(9), t4_fw_restart(9), t4_fw_upgrade(9), t4_fl_pkt_align(9), t4_fixup_host_params(9), t4_fw_initialize(9), t4_query_params_rw(9), t4_set_params_timeout(9), t4_set_params(9), t4_cfg_pfvf(9), t4_alloc_vi(9), t4_free_vi(9), t4_set_rxmode(9), t4_free_encap_mac_filt(9), t4_free_raw_mac_filt(9), t4_alloc_encap_mac_filt(9), t4_alloc_raw_mac_filt(9), t4_alloc_mac_filt(9), t4_free_mac_filt(9), t4_change_mac(9), t4_set_addr_hash(9), t4_enable_vi_params(9), t4_enable_vi(9), t4_enable_pi_params(9), t4_identify_port(9), t4_iq_stop(9), t4_iq_free(9), t4_eth_eq_free(9), t4_ctrl_eq_free(9), t4_ofld_eq_free(9), t4_link_down_rc_str(9), fwcap_to_fwspeed(9), lstatus_to_fwcap(9), t4_handle_get_port_info(9), t4_update_port_info(9), t4_get_link_params(9), t4_handle_fw_rpl(9), init_link_config(9), t4_prep_adapter(9), t4_shutdown_adapter(9), t4_init_devlog_params(9), t4_init_sge_params(9), t4_init_tp_params(9), t4_filter_field_shift(9), t4_init_portinfo(9), t4_read_cimq_cfg(9), t4_read_cim_ibq(9), t4_read_cim_obq(9), t4_cim_read(9), t4_cim_write(9), t4_cim_read_la(9), t4_tp_read_la(9), t4_idma_monitor_init(9), t4_idma_monitor(9), t4_load_cfg(9), t4_set_vf_mac_acl(9), t4_read_pace_tbl(9), t4_get_tx_sched(9), t4_sge_ctxt_rd_bd(9), t4_i2c_rd(9), t4_set_vlan_acl(9), modify_device_id(9), t4_load_boot(9), t4_flash_bootcfg_addr(9)

like I said. the whole group chat 😭🫶

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okay that's the whole page, you ate that 💅 go forth and slay your BAR2 registers, bestie 🎀

source/version: ./drivers/net/ethernet/chelsio... · October 2026 · t4_bar2_sge_qregs(9) — mwah, signing off 🍓✨