Does CubeMX skip GPDMA channel init when switching from Software to a peripheral request?

Tzahi14 · ‎2025-04-21

Hi,

I'm using STM32CubeIDE 1.18.1v, which includes STM32CubeMX 6.14.1v, and I'm seeing unexpected behavior when working with GPDMA1 on an STM32H5 device.

When I configure a DMA channel with Request set to "Software", CubeMX generates full initialization code.

However, as soon as I change the Request to any other peripheral trigger, for example TIM2_CH1, all of the DMA configuration disappears from the generated code. Only the RCC clock enable and interrupt configuration remain.

Example 1 — Request = Software:

static void MX_GPDMA1_Init(void)
{

  /* USER CODE BEGIN GPDMA1_Init 0 */

  /* USER CODE END GPDMA1_Init 0 */

  DMA_NodeConfTypeDef NodeConfig = {0};

  /* Peripheral clock enable */
  __HAL_RCC_GPDMA1_CLK_ENABLE();

  /* GPDMA1 interrupt Init */
    HAL_NVIC_SetPriority(GPDMA1_Channel0_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(GPDMA1_Channel0_IRQn);

  /* USER CODE BEGIN GPDMA1_Init 1 */

  /* USER CODE END GPDMA1_Init 1 */
  NodeConfig.NodeType = DMA_GPDMA_LINEAR_NODE;
  NodeConfig.Init.Request = DMA_REQUEST_SW;
  NodeConfig.Init.BlkHWRequest = DMA_BREQ_SINGLE_BURST;
  NodeConfig.Init.Direction = DMA_MEMORY_TO_MEMORY;
  NodeConfig.Init.SrcInc = DMA_SINC_FIXED;
  NodeConfig.Init.DestInc = DMA_DINC_FIXED;
  NodeConfig.Init.SrcDataWidth = DMA_SRC_DATAWIDTH_BYTE;
  NodeConfig.Init.DestDataWidth = DMA_DEST_DATAWIDTH_BYTE;
  NodeConfig.Init.SrcBurstLength = 1;
  NodeConfig.Init.DestBurstLength = 1;
  NodeConfig.Init.TransferAllocatedPort = DMA_SRC_ALLOCATED_PORT0|DMA_DEST_ALLOCATED_PORT0;
  NodeConfig.Init.TransferEventMode = DMA_TCEM_BLOCK_TRANSFER;
  NodeConfig.Init.Mode = DMA_NORMAL;
  NodeConfig.TriggerConfig.TriggerPolarity = DMA_TRIG_POLARITY_MASKED;
  NodeConfig.DataHandlingConfig.DataExchange = DMA_EXCHANGE_NONE;
  NodeConfig.DataHandlingConfig.DataAlignment = DMA_DATA_RIGHTALIGN_ZEROPADDED;
  NodeConfig.SrcAddress = 0;
  NodeConfig.DstAddress = 0;
  NodeConfig.DataSize = 0;
  if (HAL_DMAEx_List_BuildNode(&NodeConfig, &Node_GPDMA1_Channel0) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_DMAEx_List_InsertNode(&List_GPDMA1_Channel0, NULL, &Node_GPDMA1_Channel0) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_DMAEx_List_SetCircularMode(&List_GPDMA1_Channel0) != HAL_OK)
  {
    Error_Handler();
  }
  handle_GPDMA1_Channel0.Instance = GPDMA1_Channel0;
  handle_GPDMA1_Channel0.InitLinkedList.Priority = DMA_LOW_PRIORITY_LOW_WEIGHT;
  handle_GPDMA1_Channel0.InitLinkedList.LinkStepMode = DMA_LSM_FULL_EXECUTION;
  handle_GPDMA1_Channel0.InitLinkedList.LinkAllocatedPort = DMA_LINK_ALLOCATED_PORT1;
  handle_GPDMA1_Channel0.InitLinkedList.TransferEventMode = DMA_TCEM_BLOCK_TRANSFER;
  handle_GPDMA1_Channel0.InitLinkedList.LinkedListMode = DMA_LINKEDLIST_CIRCULAR;
  if (HAL_DMAEx_List_Init(&handle_GPDMA1_Channel0) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_DMAEx_List_LinkQ(&handle_GPDMA1_Channel0, &List_GPDMA1_Channel0) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_DMA_ConfigChannelAttributes(&handle_GPDMA1_Channel0, DMA_CHANNEL_NPRIV) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN GPDMA1_Init 2 */

  /* USER CODE END GPDMA1_Init 2 */

}

Example 2 — Request = TIM2_CH1:

static void MX_GPDMA1_Init(void)
{

  /* USER CODE BEGIN GPDMA1_Init 0 */

  /* USER CODE END GPDMA1_Init 0 */

  /* Peripheral clock enable */
  __HAL_RCC_GPDMA1_CLK_ENABLE();

  /* GPDMA1 interrupt Init */
    HAL_NVIC_SetPriority(GPDMA1_Channel0_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(GPDMA1_Channel0_IRQn);

  /* USER CODE BEGIN GPDMA1_Init 1 */

  /* USER CODE END GPDMA1_Init 1 */
  /* USER CODE BEGIN GPDMA1_Init 2 */

  /* USER CODE END GPDMA1_Init 2 */

}

Is this expected behavior when using a peripheral request instead of Software?
Or should CubeMX generate the same kind of init code regardless of the request type?

Thanks in advance!