STM32G431KB; Fatal problem with USB initialization function

[SKang.2]

FreeRTOS is currently active. However, the problem occurs before FreeRTOS initialization (before calling osKernelInitialize ()).

The board used is a board written by hand rather than a NUCLEO board. When I activate my Peripheral devices other than USB-PD and run the FreeRTOS application, I confirm that it works correctly.

The point where the problem occurs is inside the USB_DisableGlobalInt function. In the process of masking the interrupt mask to USBx-> CNTR, all interrupts are immediately interrupted (including the SWD of ST-LINK) and the chip is reset after a certain time.

Here is the call stack at the time of occurrence:

[0] from 0x08004b88 in USB_DisableGlobalInt+0 at Drivers/STM32G4xx_HAL_Driver/Src/stm32g4xx_ll_usb.c:117

[1] from 0x08004aa0 in HAL_PCD_Init+28 at Drivers/STM32G4xx_HAL_Driver/Src/stm32g4xx_hal_pcd.c:169

[2] from 0x08000908 in MX_USB_PCD_Init+32 at Src/main.c:483

[3] from 0x080009b2 in main+34 at Src/main.c:122

The code for each call stack is as follows:

[0]

 106  HAL_StatusTypeDef USB_DisableGlobalInt(USB_TypeDef *USBx)
 107  {
 108    uint16_t winterruptmask;
 109
 110    /* Set winterruptmask variable */
 111    winterruptmask = USB_CNTR_CTRM  | USB_CNTR_WKUPM |
 112                     USB_CNTR_SUSPM | USB_CNTR_ERRM |
 113                     USB_CNTR_SOFM | USB_CNTR_ESOFM |
 114                     USB_CNTR_RESETM | USB_CNTR_L1REQM;
 115
 116    /* Clear interrupt mask */
 117    USBx->CNTR &= ~winterruptmask; // << Stucks at this point
 118
 119    return HAL_OK;
 120  }

[1]

 154      {
 155        hpcd->MspInitCallback = HAL_PCD_MspInit;
 156      }
 157
 158      /* Init the low level hardware */
 159      hpcd->MspInitCallback(hpcd);
 160  #else
 161      /* Init the low level hardware : GPIO, CLOCK, NVIC... */
 162      HAL_PCD_MspInit(hpcd);
 163  #endif /* (USE_HAL_PCD_REGISTER_CALLBACKS) */
 164    }
 165
 166    hpcd->State = HAL_PCD_STATE_BUSY;
 167
 168    /* Disable the Interrupts */
 169    __HAL_PCD_DISABLE(hpcd); // <<< Stucks At This Point
 170
 171    /* Init endpoints structures */
 172    for (i = 0U; i < hpcd->Init.dev_endpoints; i++)
 173    {

[2]

 475    hpcd_USB_FS.Instance = USB;
 476    hpcd_USB_FS.Init.dev_endpoints = 8;
 477    hpcd_USB_FS.Init.speed = PCD_SPEED_FULL;
 478    hpcd_USB_FS.Init.phy_itface = PCD_PHY_EMBEDDED;
 479    hpcd_USB_FS.Init.Sof_enable = DISABLE;
 480    hpcd_USB_FS.Init.low_power_enable = DISABLE;
 481    hpcd_USB_FS.Init.lpm_enable = DISABLE;
 482    hpcd_USB_FS.Init.battery_charging_enable = DISABLE;
 483    if (HAL_PCD_Init(&hpcd_USB_FS) != HAL_OK) // << Stucks at this point
 484    {

I don't know if this is a known issue, but I couldn't find it when I tried searching on Google.

Please let me know if there is any additional information you need to solve the problem, such as board configuration or CubeMX settings.

Thanks.​

[SKang.2]

Sorry for giving vague description for my situation ...

Can you check whether my external crystal circuits correctly composited?

The error was resolved when I switched clock source to HSI ...

Should I reduce C2 and C3 on here?

In this case, Pin 2 and 4 of crystal is just shield pin ... don't care it.

[waclawek.jan · Accepted solution]

> The error was resolved when I switched clock source to HSI ...

So it was missing clock to USB?

But, you've said above,

> It is set to use HSI48,.

So how is it?

For crystal capacitors see AN2867, but generally 22pF for 24MHz should be in most of the cases OK and the oscillator should work, even if not optimally. Check HSE oscillations by outputting it to MCO and measuring there.

JW

[SKang.2]

For your question; I'm not sure what the exact cause was. When I changed the clock source for the entire system to HSI from the HSE clock, the program run without any error. 

At least, it wasn't because of the missing clock to USB. The clock source for the USB peripheral has always been HSI48 without change ... 

At this point, guessing that the crystal circuit has some trouble seems reasonable.

To ensure this, I should measure the exact clock speed of HSE... as you mentioned. 

I'll check it, thanks.

[WPete.2]

Hi!

I'm actually facing a similar issue, also in USB_DisableGlobalInt and with G431KB.

The MCU is operating as normal for other peripherals, e.g. I can run a simple blinky program and it works fine.

But when i enable the USB functionality, the MCU ends up with a fatal crash in USB_DisableGlobalInt.

I've traced this down to accessing the USB_FS_DEVICE registers, for example CNTR. Reading this register causes a fatal crash. (screenshot)

I've verified that RCC->APB1ENR1->USBDEN is set. (screenshot).

I'm using HSI (screenshot of RCC->CR). (screenshot)

Note: The regnames don't exactly match the STM RM0440 PDF manual, but the bit numbers is listed on the right for refence.

I've tried a number of options, and really am quite stuck now :(

Hoping someone here might have the same issue or some hint on how to resolve it.

@SKang.2​ : Did you ever figure out the true cause of your issue?

@WPete.2​ : You had some good comments on SKang's issue - any insights as to what I might be facing?

Detailed screenshots below...

Crashing Source Code Segment:

Disassembly

CPU Registers before crash

Fatal Crash (after executing ldhr.w instruction (i.e. reading USB_CNTR@0x40005c40)

I also get a crash if I use the debugger to read that memory space.

APB1ENR1 (I.e. USB clock enabled)

APB1ENR2 (i.e. USB-C power functinality disabled)

RCC->CR (i.e. HSI mode selected)

RCC->PLLCFGR (i.e. HSI Mode and clock configuration)

[waclawek.jan]

Next time, please start your own thread, with links to relevant threads.

How is the 48MHz clock (USB, RNG) selected? See RCC_CCIPR.CLK48SEL. If you did not touch it, it's set to HSI48.

HSI48 is enabled? See RCC_CRRCR.

JW

[WPete.2]

Hi!

Ah, hah! Yeah, that was it. RCC_CRRCR.HSI48 was not enabled, so the USB was not getting a proper clock. Flipped the bit and then it went just fine!

Thanks!!