Wifi module gets stuck during iperf3 tests

The wifi module gets stuck during iper3 tests. The issue mostly appears using --reverse or --bidir options (client is running on the stm32).

The issue was reproduced on STM32MP135F-DK and STM32MP157F-DK2, but some other platforms should be impacted.

Note that this issue was also reproduce using the ST yocto (tag openstlinux-6.1-yocto-mickledore-mp1-v24.03.13).

iperf3 -c 192.168.1.105 -t 300 -i 10 --bidir
Connecting to host 192.168.1.105, port 5201
[  5] local 192.168.1.111 port 38108 connected to 192.168.1.105 port 5201
[  7] local 192.168.1.111 port 38114 connected to 192.168.1.105 port 5201
[ ID][Role] Interval           Transfer     Bitrate         Retr  Cwnd
[  5][TX-C]   0.00-10.00  sec  21.2 MBytes  17.8 Mbits/sec    0   1007KBytes
[  7][RX-C]   0.00-10.00  sec  17.9 MBytes  15.0 Mbits/sec
[  5][TX-C]  10.00-20.00  sec  17.2 MBytes  14.4 Mbits/sec    0   1.76MBytes
[  7][RX-C]  10.00-20.00  sec  18.6 MBytes  15.6 Mbits/sec
[  5][TX-C]  20.00-30.00  sec  12.6 MBytes  10.5 Mbits/sec    1   1.41KBytes
[  7][RX-C]  20.00-30.00  sec  14.4 MBytes  12.0 Mbits/sec
[  5][TX-C]  30.00-40.01  sec  0.00 Bytes  0.00 bits/sec    0   1.41 KBytes
[  7][RX-C]  30.00-40.01  sec  0.00 Bytes  0.00 bits/sec
[  5][TX-C]  40.01-50.01  sec  0.00 Bytes  0.00 bits/sec    0   1.41 KBytes
[  7][RX-C]  40.01-50.01  sec  0.00 Bytes  0.00 bits/sec
[  5][TX-C]  50.01-60.01  sec  0.00 Bytes  0.00 bits/sec    0   1.41 KBytes
[  7][RX-C]  50.01-60.01  sec  0.00 Bytes  0.00 bits/sec
^C[  5][TX-C]  60.01-62.56  sec  0.00 Bytes  0.00 bits/sec    0   1.41KBytes
[  7][RX-C]  60.01-62.56  sec  0.00 Bytes  0.00 bits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID][Role] Interval           Transfer     Bitrate         Retr
[  5][TX-C]   0.00-62.56  sec  50.9 MBytes  6.82 Mbits/sec    1   sender
[  5][TX-C]   0.00-62.56  sec  0.00 Bytes  0.00 bits/sec receiver
[  7][RX-C]   0.00-62.56  sec  0.00 Bytes  0.00 bits/sec sender
[  7][RX-C]   0.00-62.56  sec  50.9 MBytes  6.82 Mbits/sec   receiver
iperf3: interrupt - the client has terminated

The only way to recover the module is to reset the board.

From ST point of view, the issue comes from the SDIO Out Of Band interrupt implementation for the WIFI. A workaround is to pass from Out Of Band interrupt to In Band interrupt.

To do it we need to:

Apply this patch on the devicetree


diff --git a/arch/arm/boot/dts/stm32mp135f-dk.dts b/arch/arm/boot/dts/stm32mp135f-dk.dts                                                                                                                                                                                                  
index bee689f2ee8e..545697f43c7b 100644                                                                                                                                                                                                                                                   
--- a/arch/arm/boot/dts/stm32mp135f-dk.dts                                                                                                                                                                                                                                                
+++ b/arch/arm/boot/dts/stm32mp135f-dk.dts                                                                                                                                                                                                                                                
@@ -494,6 +494,7 @@ &sdmmc2 {                                                                                                                                                                                                                                                             
    pinctrl-1 = <&sdmmc2_b4_od_pins_a &sdmmc2_clk_pins_a>;                                                                                                                                                                                                                            
    pinctrl-2 = <&sdmmc2_b4_sleep_pins_a>;                                                                                                                                                                                                                                            
    non-removable;

cap-sdio-irq;
st,neg-edge;
bus-width = <4>;
vmmc-supply = <&v3v3_ao>;
@@ -505,9 +506,6 @@ &sdmmc2 {
brcmf: bcrmf@1 {
reg = <1>;
compatible = "brcm,bcm4329-fmac";
interrupt-parent = <&gpiof>;
interrupts = <0 IRQ_TYPE_LEVEL_HIGH>; / WL_HOST_WAKE /
interrupt-names = "host-wake";
};
};


* Comment the following line in the NVRAM configuration file of the WIFI module (/lib/firmware/brcm/brcmfmac43430-sdio.st,stm32mp135f-dk.txt):
```# muxenab=0x10```

bootlin / buildroot-external-st

Wifi module gets stuck during iperf3 tests #54