xref: /openwifi/doc/app_notes/perf_counter.md (revision f6dab9cd3b99d323016724884a68c1b4e40397ed)
117cfeb0bSXianjun Jiao<!--
217cfeb0bSXianjun JiaoAuthor: Xianjun jiao
317cfeb0bSXianjun JiaoSPDX-FileCopyrightText: 2019 UGent
417cfeb0bSXianjun JiaoSPDX-License-Identifier: AGPL-3.0-or-later
517cfeb0bSXianjun Jiao-->
617cfeb0bSXianjun Jiao
717cfeb0bSXianjun Jiao
817cfeb0bSXianjun JiaoCounter/statistics (number of TX packet, RX packet, etc.) in FPGA is offered via side channel register write/read.
917cfeb0bSXianjun Jiao
1017cfeb0bSXianjun JiaoThe 1st step is alway loading the side channel kernel module:
1117cfeb0bSXianjun Jiao```
1217cfeb0bSXianjun Jiaoinsmod side_ch.ko
1317cfeb0bSXianjun Jiao```
1417cfeb0bSXianjun Jiao
1517cfeb0bSXianjun JiaoThe register write command is:
1617cfeb0bSXianjun Jiao```
1717cfeb0bSXianjun Jiao./side_ch_ctl whXdY
1817cfeb0bSXianjun JiaoX -- register index
1917cfeb0bSXianjun JiaoY -- decimal value to be written
2017cfeb0bSXianjun Jiao./side_ch_ctl whXhY
2117cfeb0bSXianjun JiaoX -- register index
2217cfeb0bSXianjun JiaoY -- hex value to be written (useful for MAC address)
2317cfeb0bSXianjun Jiao```
2417cfeb0bSXianjun JiaoWrite register 26~31 with arbitrary value to reset the corresponding counter to 0.
2517cfeb0bSXianjun Jiao
2617cfeb0bSXianjun JiaoThe register read command is:
2717cfeb0bSXianjun Jiao```
2817cfeb0bSXianjun Jiao./side_ch_ctl rhX
2917cfeb0bSXianjun JiaoX -- register index
3017cfeb0bSXianjun Jiao```
3117cfeb0bSXianjun Jiao
3217cfeb0bSXianjun Jiao## Register definition
3317cfeb0bSXianjun Jiao
3417cfeb0bSXianjun JiaoThe register 26~31 readback value represents the number of event happened. Each register has two event sources that can be selected via bit in register 19.
3517cfeb0bSXianjun Jiao
3617cfeb0bSXianjun Jiaoregister idx|source selection reg19|event
3717cfeb0bSXianjun Jiao------------|----------------------|-----------
3817cfeb0bSXianjun Jiao26          |reg19[0] == 0         |short_preamble_detected
3917cfeb0bSXianjun Jiao26          |reg19[0] == 1         |phy_tx_start
4017cfeb0bSXianjun Jiao27          |reg19[4] == 0         |long_preamble_detected
4117cfeb0bSXianjun Jiao27          |reg19[4] == 1         |phy_tx_done
4217cfeb0bSXianjun Jiao28          |reg19[8] == 0         |pkt_header_valid_strobe
4317cfeb0bSXianjun Jiao28          |reg19[8] == 1         |rssi_above_th
4417cfeb0bSXianjun Jiao29          |reg19[12] == 0        |pkt_header_valid_strobe&pkt_header_valid
4517cfeb0bSXianjun Jiao29          |reg19[12] == 1        |gain_change
4617cfeb0bSXianjun Jiao30          |reg19[16] == 0        |((fcs_in_strobe&addr2_match)&pkt_for_me)&is_data
4717cfeb0bSXianjun Jiao30          |reg19[16] == 1        |agc_lock
4817cfeb0bSXianjun Jiao31          |reg19[20] == 0        |(((fcs_in_strobe&fcs_ok)&addr2_match)&pkt_for_me)&is_data
4917cfeb0bSXianjun Jiao31          |reg19[20] == 1        |tx_pkt_need_ack
5017cfeb0bSXianjun Jiao
5117cfeb0bSXianjun JiaoNote: fcs_in_strobe means decoding is done (not necessarily CRC is correct); fcs_ok 1 means CRC correct; fcs_ok 0 means CRC not correct.
5217cfeb0bSXianjun Jiao
5317cfeb0bSXianjun JiaoNote: addr2_match means addr2 matches to the register (addr2_target) value; pkt_for_me means addr1 matches self mac addr; is_data means the packet type is data.
5417cfeb0bSXianjun Jiao
5517cfeb0bSXianjun JiaoConfiguration register:
5617cfeb0bSXianjun Jiao
5717cfeb0bSXianjun Jiaoregister idx|meaning               |note
5817cfeb0bSXianjun Jiao------------|----------------------|-----------
5917cfeb0bSXianjun Jiao7           |addr2 target value    |fcs event always needs addr2 match
6017cfeb0bSXianjun Jiao9           |threshold for event rssi_above_th|check auto_lbt_th in ad9361_rf_set_channel of sdr.c to estimate a proper value
6117cfeb0bSXianjun Jiao
6217cfeb0bSXianjun JiaoNote: addr2 (source/sender's MAC address) target setting uses only 32bit. For address 6c:fd:b9:4c:b1:c1, you set b94cb1c1
6317cfeb0bSXianjun Jiao
64*f6dab9cdSThijs HavingaNote: read register 62 of xpu for some addr2 captured by the receiver
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