I am using Verdin iMX8M Plus WB on a custom carrier board. I have followed the Yocto build instructions and compiled a release for my board. Instead of using connmanctl, I am using wpa-supplicant to connect to the router.
I have noticed that the iMX8’s RSSI was less than another MPU, even though they were equal distance from the router. Further debug shows that the Wi-F TX Power was different: iMX8 was 8dBm, and the other MPU was 30dBM.
Below are additional commands that I tried to increase the power. Is there anything else that I can try to increase the tx power?
Confirm that only wpa_supplicant was running
root@crce-imx8-14855176:~# ps | grep conn
4269 root 3444 S grep conn
root@crce-imx8-14855176:~# ps | grep wpa
727 root 12308 S /usr/sbin/wpa_supplicant -c/etc/wpa_supplicant/wpa_supplicant-mlan0.conf -imlan0
745 root 11596 S /usr/sbin/wpa_supplicant -u
4281 root 3444 S grep wpa
Check the limits, which notes that it should be max 20dBm
root@crce-imx8-14855176:~# iw reg get
global
country 00: DFS-UNSET
(755 - 928 @ 2), (N/A, 20), (N/A), PASSIVE-SCAN
(2402 - 2472 @ 40), (N/A, 20), (N/A)
(2457 - 2482 @ 20), (N/A, 20), (N/A), AUTO-BW, PASSIVE-SCAN
(2474 - 2494 @ 20), (N/A, 20), (N/A), NO-OFDM, PASSIVE-SCAN
(5170 - 5250 @ 80), (N/A, 20), (N/A), AUTO-BW, PASSIVE-SCAN
(5250 - 5330 @ 80), (N/A, 20), (0 ms), DFS, AUTO-BW, PASSIVE-SCAN
(5490 - 5730 @ 160), (N/A, 20), (0 ms), DFS, PASSIVE-SCAN
(5735 - 5835 @ 80), (N/A, 20), (N/A), PASSIVE-SCAN
(57240 - 63720 @ 2160), (N/A, 0), (N/A)
Check current txpower, and saw that it was 8dBm
root@crce-imx8-14855176:~# iw dev mlan0 info
Interface mlan0
ifindex 7
wdev 0x1
addr 14:13:33:cc:e1:e9
ssid [redacted]
type managed
wiphy 0
channel 11 (2462 MHz), width: 20 MHz (no HT), center1: 2462 MHz
txpower 8.00 dBm
Tried to change the txpower to 16dBm
root@crce-imx8-14855176:~# iw dev mlan0 set txpower fixed 1600
command failed: Operation not permitted (-1)
mwifiex_sdio mmc0:0001:1: txpower value 16 dBm is out of range (0 dBm-8 dBm)
tdx-info
root@crce-imx8-14855176:~# tdx-info
Software summary
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Bootloader: U-Boot
Kernel version: 5.15.129-6.4.0-devel+git.67c3153d20ff #1 SMP PREEMPT Wed Sep 27 12:30:36 UTC 2023
Kernel command line: root=PARTUUID=6f825721-02 ro rootwait console=tty1 console=ttymxc2,115200 consoleblank=0 earlycon
Distro name: NAME="TDX Wayland with XWayland"
Distro version: VERSION_ID=6.4.0-devel-20240130165750-build.0
Hostname: crce-imx8-14855176
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Hardware info
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HW model: Toradex Verdin iMX8M Plus WB on Verdin Development Board
Toradex version: 0058 V1.1A
Serial number: 14855176
Processor arch: aarch64
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