esp-idf: ESP32-C3 USB JTAG/Serial console corrupted during wifi connect (IDFGH-6387)

Environment

• Development Kit: none
• Kit version (for WroverKit/PicoKit/DevKitC): N/A
• Module or chip used: ESP-C3-12F
• IDF version (run git describe --tags to find it): v5.0-dev-621-g4143a3f572
• Build System: idf.py
• Compiler version: riscv32-esp-elf-gcc (crosstool-NG esp-2021r2) 8.4.0
• Operating System: Linux
• Using an IDE?: No
• Power Supply: USB

Problem Description

When initiating a wifi connection on ESP32-C3 the attached debug session over embedded USB JTAG gets corrupted. Also USB serial console stops responding. Trying to restart openOCD without restarting ESP32-C3 ends with error: libusb_get_string_descriptor_ascii() failed with -1. The ESP32-C3 program continues to run without any problem (based on log from external USART0 console). But I am no more able to debug it. If I add some waiting before the wifi connect attempt the debugger works until the start of wifi connection. Also other examples not involving wifi connection works without any issues. After ESP-C3 restart the USB embedded JTAG and console works again until another connection attempt. I added 100uF capacitors and monitored VDD during connection on osciloscope. There are not any voltage drops below 3.1V. esp_wifi_set_ps(WIFI_PS_NONE) and esp_wifi_set_max_tx_power(8)) had no effect on this issue

Expected Behavior

The embbeded JTAG works normally after wifi connection

Actual Behavior

The embbeded JTAG/serial console do not work

Steps to reproduce

1. Run esp-idf/examples/wifi/getting_started/station example on ESP-C3-12F module.
2. Wait until the ESP is connected to an AP
3. Try to start OpenOCD over built-in jtag - you get an error

Code to reproduce this issue

esp-idf/examples/wifi/getting_started/station without any modification

Debug Logs

ESP-ROM:esp32c3-api1-20210207 Build:Feb 7 2021 rst:0x1 (POWERON),boot:0xc (SPI_FAST_FLASH_BOOT) SPIWP:0xee mode:DIO, clock div:1 load:0x3fcd6100,len:0x1740 load:0x403ce000,len:0x930 load:0x403d0000,len:0x2d4c entry 0x403ce000 I (30) boot: ESP-IDF v5.0-dev-621-g4143a3f572 2nd stage bootloader I (30) boot: compile time 13:44:40 I (30) boot: chip revision: 3 I (33) boot.esp32c3: SPI Speed : 80MHz I (38) boot.esp32c3: SPI Mode : DIO I (43) boot.esp32c3: SPI Flash Size : 2MB I (48) boot: Enabling RNG early entropy source… I (53) boot: Partition Table: I (57) boot: ## Label Usage Type ST Offset Length I (64) boot: 0 nvs WiFi data 01 02 00009000 00006000 I (71) boot: 1 phy_init RF data 01 01 0000f000 00001000 I (79) boot: 2 factory factory app 00 00 00010000 00100000 I (86) boot: End of partition table I (90) esp_image: segment 0: paddr=00010020 vaddr=3c080020 size=13570h ( 79216) map I (111) esp_image: segment 1: paddr=00023598 vaddr=3fc8e200 size=02ba4h ( 11172) load I (113) esp_image: segment 2: paddr=00026144 vaddr=40380000 size=09ed4h ( 40660) load I (124) esp_image: segment 3: paddr=00030020 vaddr=42000020 size=74de0h (478688) map I (197) esp_image: segment 4: paddr=000a4e08 vaddr=40389ed4 size=04218h ( 16920) load I (203) esp_image: segment 5: paddr=000a9028 vaddr=50000000 size=00010h ( 16) load I (207) boot: Loaded app from partition at offset 0x10000 I (209) boot: Disabling RNG early entropy source… I (225) cpu_start: Pro cpu up. I (234) cpu_start: Pro cpu start user code I (234) cpu_start: cpu freq: 160000000 Hz I (234) cpu_start: Application information: I (237) cpu_start: Project name: wifi_station I (242) cpu_start: App version: 56bdd21-dirty I (248) cpu_start: Compile time: Dec 9 2021 13:44:25 I (254) cpu_start: ELF file SHA256: 03a342e76e213be3… I (260) cpu_start: ESP-IDF: v5.0-dev-621-g4143a3f572 I (266) heap_init: Initializing. RAM available for dynamic allocation: I (273) heap_init: At 3FC94D20 len 0002B2E0 (172 KiB): DRAM I (279) heap_init: At 3FCC0000 len 0001F060 (124 KiB): STACK/DRAM I (286) heap_init: At 50000010 len 00001FF0 (7 KiB): RTCRAM I (293) spi_flash: detected chip: generic I (297) spi_flash: flash io: dio W (301) spi_flash: Detected size(4096k) larger than the size in the binary image header(2048k). Using the size in the binary image header. I (315) sleep: Configure to isolate all GPIO pins in sleep state I (321) sleep: Enable automatic switching of GPIO sleep configuration I (328) cpu_start: Starting scheduler. I (796) wifi station: ESP_WIFI_MODE_STA I (796) pp: pp rom version: 9387209 I (796) net80211: net80211 rom version: 9387209 I (816) wifi:wifi driver task: 3fc9d8a4, prio:23, stack:6656, core=0 I (816) system_api: Base MAC address is not set I (816) system_api: read default base MAC address from EFUSE I (816) wifi:wifi firmware version: c279458 I (826) wifi:wifi certification version: v7.0 I (826) wifi:config NVS flash: enabled I (826) wifi:config nano formating: disabled I (836) wifi:Init data frame dynamic rx buffer num: 32 I (836) wifi:Init management frame dynamic rx buffer num: 32 I (846) wifi:Init management short buffer num: 32 I (846) wifi:Init dynamic tx buffer num: 32 I (856) wifi:Init static tx FG buffer num: 2 I (856) wifi:Init static rx buffer size: 1600 I (856) wifi:Init static rx buffer num: 10 I (866) wifi:Init dynamic rx buffer num: 32 I (866) wifi_init: rx ba win: 6 I (876) wifi_init: tcpip mbox: 32 I (876) wifi_init: udp mbox: 6 I (876) wifi_init: tcp mbox: 6 I (886) wifi_init: tcp tx win: 5744 I (886) wifi_init: tcp rx win: 5744 I (896) wifi_init: tcp mss: 1440 I (896) wifi_init: WiFi IRAM OP enabled I (896) wifi_init: WiFi RX IRAM OP enabled I (916) phy_init: phy_version 906,ed5370c,Nov 8 2021,18:01:10 W (916) phy_init: failed to load RF calibration data (0x1102), falling back to full calibration I (966) wifi:mode : sta (84:f7:03:3b:11:0c) I (966) wifi:enable tsf I (966) wifi station: wifi_init_sta finished. I (2176) wifi🆕<11,0>, old:<1,0>, ap:<255,255>, sta:<11,0>, prof:1 I (2796) wifi:state: init -> auth (b0) I (3796) wifi:state: auth -> init (200) I (3796) wifi🆕<11,0>, old:<11,0>, ap:<255,255>, sta:<11,0>, prof:1 I (3796) wifi station: retry to connect to the AP I (3796) wifi station: connect to the AP fail I (5846) wifi station: retry to connect to the AP I (5846) wifi station: connect to the AP fail I (5846) wifi🆕<11,0>, old:<11,0>, ap:<255,255>, sta:<11,0>, prof:1 I (5846) wifi:state: init -> auth (b0) I (5856) wifi:state: auth -> assoc (0) I (5876) wifi:state: assoc -> run (10) I (5896) wifi:connected with ap, aid = 4, channel 11, BW20, bssid = 50:8f:4c:d1:ca:05 I (5896) wifi:security: WPA2-PSK, phy: bgn, rssi: -53 I (5906) wifi:pm start, type: 1

I (5906) wifi:set rx beacon pti, rx_bcn_pti: 0, bcn_timeout: 0, mt_pti: 25000, mt_time: 10000 I (5936) wifi:BcnInt:102400, DTIM:2 I (6796) esp_netif_handlers: sta ip: 192.168.43.40, mask: 255.255.255.0, gw: 192.168.43.1 I (6796) wifi station: got ip:192.168.43.40 I (6796) wifi station: connected to ap SSID:ap password:######

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openocd -f board\esp32c3-builtin.cfg Open On-Chip Debugger v0.10.0-esp32-20211111 (2021-11-10-21:40) Licensed under GNU GPL v2 For bug reports, read http://openocd.org/doc/doxygen/bugs.html Info : only one transport option; autoselect ‘jtag’ Warn : Transport “jtag” was already selected Info : Listening on port 6666 for tcl connections Info : Listening on port 4444 for telnet connections Error: libusb_get_string_descriptor_ascii() failed with -1