Where to find documentation on STM32U575 HAL Driver API and its structure

 I have downlaoded package for STM32U575 controller and going through its example projects.

I want to know where I can find documentation for the HAL drivers for this controller? Any Wiki site for it?

As an example, I see below DMA2D strcture in the initialization code. Where to find documentation for this structure DMA2D_HandleTypeDef? What does DMA2D_R2M mode means? Similar question for all HAL drivers.

static void MX_DMA2D_Init(void)
{

 /* USER CODE BEGIN DMA2D_Init 0 */

 /* USER CODE END DMA2D_Init 0 */

 /* USER CODE BEGIN DMA2D_Init 1 */

 /* USER CODE END DMA2D_Init 1 */
 hdma2d.Instance = DMA2D;
 hdma2d.Init.Mode = DMA2D_R2M;
 hdma2d.Init.ColorMode = DMA2D_OUTPUT_RGB565;
 hdma2d.Init.OutputOffset = 0;
 hdma2d.Init.BytesSwap = DMA2D_BYTES_REGULAR;
 hdma2d.Init.LineOffsetMode = DMA2D_LOM_PIXELS;
 if (HAL_DMA2D_Init(&hdma2d) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN DMA2D_Init 2 */

 /* USER CODE END DMA2D_Init 2 */

}

DMA2D_HandleTypeDef