NXP Semiconductors UM11490 - Transmit Power Enable

NXP Semiconductors
UM11490
Feature Configuration Guide for NXP-based Wireless Modules on i.MX 8M Quad EVK
2.9.2 Transmit power enable
This section provides the steps to enable transmit (Tx) power.
Step 1 - Edit the configuration file
The Tx power levels are set with txpwrlimit_2g_cfg_set and
txpwrlimit_5g_cfg _set data structures defined in txpwrlimit_cfg.conf configuration
file.
Use the configuration file to specify the transmit power levels for the frequency, channels,
power and channel-width.
Step 2 - Convert the configuration file
The TX power configuration file txpwrlimit_cfg.conf must be converted to a binary (.bin)
format so the wireless driver can use it.
The following command uses mlanutl utility stored at the following location: /usr/share/
nxp_wireless/bin_mxm_wifiex/ to convert the configuration file to a bin format.
mlanutl <wireless interface> hostcmd <conf_file_name> generate_raw
<bin_file_name>
• <wireless interface> is the wireless interface used in the system, for example
mlan0
• <conf_file_name> is the name of Tx power configuration file
• <bin_file_name> is the name of the output bin file to be generated
Example
root@imx8mqevk:~# ./mlanutl mlan0 hostcmd txpwrlimit_cfg_8987.conf
generate_raw txpower_US.bin
returns:
root@imx8mqevk:~# ./mlanutl mlan0 hostcmd ./config/
txpwrlimit_cfg.conf generate_raw txpower_US.bin
Copy the newly generated binary files into the wireless firmware directory. For Linux
systems, the directory is: /lib/firmware/nxp.
Step 3 - Load Tx power table configuration
The Tx Power table binary file is activated during the wireless driver load time. In the
following example, the driver loads txpower_US.bin using txpwrlimit_cfg parameter:
root@imx8mqevk:~# nano /lib/firmware/nxp/wifi_mod_para_sd8987.conf
SD8987 = {
cfg80211_wext=0xf
wfd_name=p2p
cal_data_cfg=none
max_vir_bss=1
fw_name=nxp/sdiouart8987_combo_v0.bin
txpwrlimit_cfg=nxp/txpower_US.bin
}
Run the following command to load the module:
root@imx8mqevk:~# modprobe moal mod_para=nxp/wifi_mod_para_sd8987.conf
UM11490 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2021. All rights reserved.
User manual Rev. 2 — 29 January 2021
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