sf1_read(9)

💅 sf1_read(9) — like, the serial-flash read, bestie

okay so real talk, this is a page from the Kernel API Manual and it's about sf1_read. sit down, grab a strawberry drink 🍓, and let me tell you about pulling bytes out of a serial flash. it's giving tiny-read energy and honestly? iconic.

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✨ NAME ✨

sf1_read — read data from the serial flash

🌸 SYNOPSIS 🌸

int sf1_read (struct adapter *adapter , unsigned int byte_cnt , int cont , int lock , u32 *valp );

🎀 ARGUMENTS 🎀

• adapter — the adapter. yes, the adapter. it's the little guy doing all the work 🫶
• byte_cnt — number of bytes to read
• cont — whether another operation will be chained
• lock — whether to lock SF for PL access only
• valp — where to store the read data

🦋 DESCRIPTION 🦋

Reads up to 4 bytes of data from the serial flash. four. that's it. that's the whole vibe. 💀

🚨 and listen, this is the important part, don't skip it: the location of the read needs to be specified prior to calling this by issuing the appropriate commands to the serial flash. so like... you gotta tell it where first. this function does not magically know. no cap.

👑 SEE ALSO 👑

first up, the kernel file itself, living its best life at ./drivers/net/ethernet/chelsio/cxgb4/t4_hw.c 🧚

and now the friend group — the whole squad of neighbors, fr fr:

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_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_bar2_sge_qregs(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 squad. 💜

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and that's the page!! this gem lives in ./drivers/net/ethernet/chelsio... and it's stamped October 2026 — so yeah, go read your flash, but only like 4 bytes at a time, and set the location first, mwah 💅✨