STM32N6 SystemIsolation_Config

[jrocher-althea]

Hello all,

I'm working with the STM32N6 series and I'm trying to correctly configure the isolation between the secure and non-secure domains using the RIF (Runtime Isolation Framework).

I found example code like this in a template (STM32CubeN6)

 static void SystemIsolation_Config(void)
{

  /* USER CODE BEGIN RIF_Init 0 */

  /* USER CODE END RIF_Init 0 */

  /* set all required IPs as secure privileged */
  __HAL_RCC_RIFSC_CLK_ENABLE();
  RIMC_MasterConfig_t RIMC_master = {0};
  RIMC_master.MasterCID = RIF_CID_1;
  RIMC_master.SecPriv = RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_PRIV;

  /*RIMC configuration*/
  HAL_RIF_RIMC_ConfigMasterAttributes(RIF_MASTER_INDEX_ETH1, &RIMC_master);

  /*RISUP configuration*/
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_ADC12 , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_CSI , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_ETH1 , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_I2C1 , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_I2C2 , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_ICACHE , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_LPUART1 , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_XSPI2 , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);
  HAL_RIF_RISC_SetSlaveSecureAttributes(RIF_RISC_PERIPH_INDEX_XSPIM , RIF_ATTRIBUTE_SEC | RIF_ATTRIBUTE_NPRIV);

  /* RIF-Aware IPs Config */

  /* set up GPIO configuration */
  HAL_GPIO_ConfigPinAttributes(GPIOA,GPIO_PIN_10,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOA,GPIO_PIN_11,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOB,GPIO_PIN_0,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOB,GPIO_PIN_3,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOB,GPIO_PIN_6,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOB,GPIO_PIN_7,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOB,GPIO_PIN_10,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOB,GPIO_PIN_11,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOC,GPIO_PIN_1,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOE,GPIO_PIN_3,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOE,GPIO_PIN_6,GPIO_PIN_SEC|GPIO_PIN_NPRIV);
  HAL_GPIO_ConfigPinAttributes(GPIOH,GPIO_PIN_9,GPIO_PIN_SEC|GPIO_PIN_NPRIV);

  /* USER CODE BEGIN RIF_Init 1 */

  /* USER CODE END RIF_Init 1 */
  /* USER CODE BEGIN RIF_Init 2 */

  /* USER CODE END RIF_Init 2 */

}

However, I’m unclear on:

1. How to correctly configure GPIOs/Periphals used by non-secure applications.

2. Whether there’s an official list or documentation for the STM32N6 that shows all RIF-aware peripherals and their indices (like RIF_RISC_PERIPH_INDEX_*).

3. Any guidance or reference templates for properly setting up the isolation for a basic non-secure application (e.g., accessing UART and I2C from non-secure code).

Any help or pointers to documentation specific to STM32N6 and TrustZone+RIF configuration would be greatly appreciated!

Thanks in advance.