Timer Interrupts on M4 core - STM32MP157C

[shane mattner]

I'm trying to get TIM7 interrupts working with the STM32MP157C-DK2 kit. I've added the necessary configuration to the DTS file:

&m4_timers7 {
	pinctrl-names = "rproc_default";
	pinctrl-0 = <&timer7_pins>;
	status = "okay";
};

Do I need to enable the interrupt in the DTS file as well? I see in the M4 example DTS there is some configuration for a GPIO interrupt:

&m4_rproc {
	m4_system_resources {
		status = "okay";
 
		button {
			compatible = "rproc-srm-dev";
			interrupt-parent = <&gpioa>;
			interrupts = <14 2>;
			interrupt-names = "irq";
			status = "okay";
		};
 
		m4_led: m4_led {
			compatible = "rproc-srm-dev";
			pinctrl-names = "rproc_default", "rproc_sleep";
			pinctrl-0 = <&leds_orange_pins>;
			pinctrl-1 = <&leds_orange_sleep_pins>;
			status = "okay";
		};
	};
};

On the M4 side: I've configured TIM7 in CubeMX (prescalar: 10000, period: 100, interrupt enabled). The only configuration I see for TIM7 comes from MX_TIM7_Init():

void MX_TIM7_Init(void)
{
  TIM_MasterConfigTypeDef sMasterConfig = {0};
 
  htim7.Instance = TIM7;
  htim7.Init.Prescaler = 10000;
  htim7.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim7.Init.Period = 100;
  htim7.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
  if (HAL_TIM_Base_Init(&htim7) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim7, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
 
}

But I don't see anything about interrupts here. There is another function HAL_TIM_Base_MspInit() that I've tried to use without success. I tried calling this function after the init function above was called.

void HAL_TIM_Base_MspInit(TIM_HandleTypeDef* tim_baseHandle)
{
 
  if(tim_baseHandle->Instance==TIM7)
  {
  /* USER CODE BEGIN TIM7_MspInit 0 */
 
  /* USER CODE END TIM7_MspInit 0 */
    /* TIM7 clock enable */
    __HAL_RCC_TIM7_CLK_ENABLE();
 
    /* TIM7 interrupt Init */
    HAL_NVIC_SetPriority(TIM7_IRQn, 5, 0);
    HAL_NVIC_EnableIRQ(TIM7_IRQn);
  /* USER CODE BEGIN TIM7_MspInit 1 */
 
  /* USER CODE END TIM7_MspInit 1 */
  }
}

Anyone have an idea what might be going on that the interrupt isn't firing?

[PatrickF · Accepted solution]

Hi,

did you started the timer in your main code (e.g. HAL_TIM_Base_Start_IT(TIM_HandleTypeDef *htim) ) ?

Maybe missing the interrupt handler in stm32mp1xx_it.c

Please have a look to examples in STM32CubeMP1, e.g. in Projects\STM32MP157C-EV1\Examples\LPTIM\LPTIM_PulseCounter (although not TIM, but usage at HAL level is very similar).

STM32CubeMP1 is usually already loaded in your PC by CubeMX (e.g. on W10 in C:\Users\xxxx\STM32Cube\Repository) or could be loaded manually on st.com or on Github

Regards.

[shane mattner]

HAL_TIM_Base_Start_IT() was missing. Thanks for the reply