Can DMA trigger MDMA block transfer (linked list)

[elso]

Hi All,

I have a program that is supposed to transfer data from the integrated ADC on STM32H723 to the D1 RAM. I am using DMA for this, but the problem is that the DMA buffer is limited to 64KB, where I need around 200-250 KB buffer size. Here I am thinking about using DMA as a circular buffer, where I want 

void HAL_ADC_ConvHalfCpltCallback(ADC_HandleTypeDef* hadc){
	//Trigger MDMA block transfer
}

//Called when buffer is completely filled
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc){
	//Trigger MDMA block transfer
}

to trigger a block transfer from half the DMA buffer to the MDMA buffer (to one linked list node), or simply using a flag. However is this possible? Can I link a flag or something else to trigger a MDMA linked list block transfer? The linked list will consist of 8 nodes of half the DMA buffer size, so that the functionality will be like a circular buffer of ~200 KB.

If someone have done something similar or have an idea how to solve this, I would really appreciate it! 

Best regards

[elso · Accepted solution]

After a week of headscratching I have made it work! For those who struggle with MDMA here is a code using a circular buffered linked list. The SRC_Buffer can simulate an ADC who have filled one half of a buffer using DMA. Then the DMA callback funcitons can trigger the MDMA to transfer the data to bigger buffers fast.

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2023 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define SRC_BUF_SIZE 50000 //65472
#define SRC_BUF_HALF_SIZE 25000 //32736
#define DST_BUF_SIZE 25000 //32736
#define XFR_BUF_SIZE 25000 //32736
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

MDMA_HandleTypeDef hmdma_mdma_channel0_sw_0;
MDMA_LinkNodeTypeDef node_mdma_channel0_sw_1;
/* USER CODE BEGIN PV */
MDMA_LinkNodeTypeDef node_mdma_channel0_sw_2;
MDMA_LinkNodeTypeDef node_mdma_channel0_sw_3;
MDMA_LinkNodeTypeDef node_mdma_channel0_sw_4;
MDMA_LinkNodeTypeDef node_mdma_channel0_sw_5;

uint8_t SRC_Buf0[SRC_BUF_SIZE];
uint8_t* SRC_Buf1 = &SRC_Buf0[SRC_BUF_HALF_SIZE];
uint8_t DST_Buf0[DST_BUF_SIZE];
uint8_t DST_Buf1[DST_BUF_SIZE];
uint8_t DST_Buf2[DST_BUF_SIZE];
uint8_t DST_Buf3[DST_BUF_SIZE];
uint8_t DST_Buf4[DST_BUF_SIZE];
uint8_t DST_Buf5[DST_BUF_SIZE];
/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MPU_Initialize(void);
static void MPU_Config(void);
static void MX_MDMA_Init(void);
/* USER CODE BEGIN PFP */
static void MDMA_TransferCompleteCallback(MDMA_HandleTypeDef *hmdma);
static void MDMA_TransferErrorCallback(MDMA_HandleTypeDef *hmdma);
static void MDMA_TransferBlockCompleteCallback(MDMA_HandleTypeDef *hmdma);
//static void MDMA_TransferBufferCompleteCallback(MDMA_HandleTypeDef *hmdma);
/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
	unsigned int j = 0;
	for(unsigned int i = 0; i < SRC_BUF_SIZE; i++){
		SRC_Buf0[i] = j;
		j++;
		if(j >= 256){
			j = 0;
		}
	}
	for(unsigned int i = 0; i < DST_BUF_SIZE; i++){
		DST_Buf0[i] = 0;
		DST_Buf1[i] = 0;
		DST_Buf2[i] = 0;
		DST_Buf3[i] = 0;
		DST_Buf4[i] = 0;
		DST_Buf5[i] = 0;
	}
	__NOP();
  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* MPU Configuration--------------------------------------------------------*/
  MPU_Config();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_MDMA_Init();
  /* USER CODE BEGIN 2 */
  if (HAL_MDMA_Start_IT(&hmdma_mdma_channel0_sw_0, (uint32_t)&SRC_Buf0, (uint32_t)&DST_Buf0, XFR_BUF_SIZE, 1) != HAL_OK)
  {
	  __NOP();
  }
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Supply configuration update enable
  */
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);

  while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_DIV1;
  RCC_OscInitStruct.HSICalibrationValue = 64;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 4;
  RCC_OscInitStruct.PLL.PLLN = 34;
  RCC_OscInitStruct.PLL.PLLP = 1;
  RCC_OscInitStruct.PLL.PLLQ = 2;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_3;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  RCC_OscInitStruct.PLL.PLLFRACN = 3072;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2
                              |RCC_CLOCKTYPE_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * Enable MDMA controller clock
  * Configure MDMA for global transfers
  *   hmdma_mdma_channel0_sw_0
  *   node_mdma_channel0_sw_1
  */
static void MX_MDMA_Init(void)
{

  /* MDMA controller clock enable */
  __HAL_RCC_MDMA_CLK_ENABLE();
  /* Local variables */
  MDMA_LinkNodeConfTypeDef nodeConfig;

  /* Configure MDMA channel MDMA_Channel0 */
  /* Configure MDMA request hmdma_mdma_channel0_sw_0 on MDMA_Channel0 */
  hmdma_mdma_channel0_sw_0.Instance = MDMA_Channel0;
  hmdma_mdma_channel0_sw_0.Init.Request = MDMA_REQUEST_SW;
  hmdma_mdma_channel0_sw_0.Init.TransferTriggerMode = MDMA_BLOCK_TRANSFER;
  hmdma_mdma_channel0_sw_0.Init.Priority = MDMA_PRIORITY_VERY_HIGH;
  hmdma_mdma_channel0_sw_0.Init.Endianness = MDMA_LITTLE_ENDIANNESS_PRESERVE;
  hmdma_mdma_channel0_sw_0.Init.SourceInc = MDMA_SRC_INC_BYTE;
  hmdma_mdma_channel0_sw_0.Init.DestinationInc = MDMA_DEST_INC_BYTE;
  hmdma_mdma_channel0_sw_0.Init.SourceDataSize = MDMA_SRC_DATASIZE_BYTE;
  hmdma_mdma_channel0_sw_0.Init.DestDataSize = MDMA_DEST_DATASIZE_BYTE;
  hmdma_mdma_channel0_sw_0.Init.DataAlignment = MDMA_DATAALIGN_PACKENABLE;
  hmdma_mdma_channel0_sw_0.Init.BufferTransferLength = 1;
  hmdma_mdma_channel0_sw_0.Init.SourceBurst = MDMA_SOURCE_BURST_SINGLE;
  hmdma_mdma_channel0_sw_0.Init.DestBurst = MDMA_DEST_BURST_SINGLE;
  hmdma_mdma_channel0_sw_0.Init.SourceBlockAddressOffset = 0;
  hmdma_mdma_channel0_sw_0.Init.DestBlockAddressOffset = 0;
  if (HAL_MDMA_Init(&hmdma_mdma_channel0_sw_0) != HAL_OK)
  {
    Error_Handler();
  }

  /* Initialize MDMA link node according to specified parameters */
  nodeConfig.Init.Request = MDMA_REQUEST_SW;
  nodeConfig.Init.TransferTriggerMode = MDMA_BLOCK_TRANSFER;
  nodeConfig.Init.Priority = MDMA_PRIORITY_VERY_HIGH;
  nodeConfig.Init.Endianness = MDMA_LITTLE_ENDIANNESS_PRESERVE;
  nodeConfig.Init.SourceInc = MDMA_SRC_INC_BYTE;
  nodeConfig.Init.DestinationInc = MDMA_DEST_INC_BYTE;
  nodeConfig.Init.SourceDataSize = MDMA_SRC_DATASIZE_BYTE;
  nodeConfig.Init.DestDataSize = MDMA_DEST_DATASIZE_BYTE;
  nodeConfig.Init.DataAlignment = MDMA_DATAALIGN_PACKENABLE;
  nodeConfig.Init.BufferTransferLength = 1;
  nodeConfig.Init.SourceBurst = MDMA_SOURCE_BURST_SINGLE;
  nodeConfig.Init.DestBurst = MDMA_DEST_BURST_SINGLE;
  nodeConfig.Init.SourceBlockAddressOffset = 0;
  nodeConfig.Init.DestBlockAddressOffset = 0;
  nodeConfig.PostRequestMaskAddress = 0;
  nodeConfig.PostRequestMaskData = 0;
  nodeConfig.SrcAddress = (uint32_t)&SRC_Buf0[SRC_BUF_HALF_SIZE]; //Edited
  nodeConfig.DstAddress = (uint32_t)DST_Buf1; //Edited
  nodeConfig.BlockDataLength = XFR_BUF_SIZE; //Edited
  nodeConfig.BlockCount = 1;
  if (HAL_MDMA_LinkedList_CreateNode(&node_mdma_channel0_sw_1, &nodeConfig) != HAL_OK){Error_Handler();}

  /* USER CODE BEGIN mdma_channel0_sw_1 */
  if (HAL_MDMA_LinkedList_AddNode(&hmdma_mdma_channel0_sw_0, &node_mdma_channel0_sw_1, 0) != HAL_OK){Error_Handler();}
  /* Initialize MDMA link node according to specified parameters */
  nodeConfig.SrcAddress = (uint32_t)&SRC_Buf0[0]; //Edited
  nodeConfig.DstAddress = (uint32_t)DST_Buf2;
  if (HAL_MDMA_LinkedList_CreateNode(&node_mdma_channel0_sw_2, &nodeConfig) != HAL_OK){Error_Handler();}
  if (HAL_MDMA_LinkedList_AddNode(&hmdma_mdma_channel0_sw_0, &node_mdma_channel0_sw_2, 0) != HAL_OK){Error_Handler();}

  nodeConfig.SrcAddress = (uint32_t)&SRC_Buf0[SRC_BUF_HALF_SIZE]; //Edited
  nodeConfig.DstAddress = (uint32_t)DST_Buf3;
  if (HAL_MDMA_LinkedList_CreateNode(&node_mdma_channel0_sw_3, &nodeConfig) != HAL_OK){Error_Handler();}
  if (HAL_MDMA_LinkedList_AddNode(&hmdma_mdma_channel0_sw_0, &node_mdma_channel0_sw_3, 0) != HAL_OK){Error_Handler();}

  nodeConfig.SrcAddress = (uint32_t)&SRC_Buf0[0]; //Edited
  nodeConfig.DstAddress = (uint32_t)DST_Buf4;
  if (HAL_MDMA_LinkedList_CreateNode(&node_mdma_channel0_sw_4, &nodeConfig) != HAL_OK){Error_Handler();}
  if (HAL_MDMA_LinkedList_AddNode(&hmdma_mdma_channel0_sw_0, &node_mdma_channel0_sw_4, 0) != HAL_OK){Error_Handler();}

  nodeConfig.SrcAddress = (uint32_t)&SRC_Buf0[SRC_BUF_HALF_SIZE]; //Edited
  nodeConfig.DstAddress = (uint32_t)DST_Buf5;
  if (HAL_MDMA_LinkedList_CreateNode(&node_mdma_channel0_sw_5, &nodeConfig) != HAL_OK){Error_Handler();}
  if (HAL_MDMA_LinkedList_AddNode(&hmdma_mdma_channel0_sw_0, &node_mdma_channel0_sw_5, 0) != HAL_OK){Error_Handler();}

  HAL_MDMA_RegisterCallback(&hmdma_mdma_channel0_sw_0, HAL_MDMA_XFER_CPLT_CB_ID, MDMA_TransferCompleteCallback);
  HAL_MDMA_RegisterCallback(&hmdma_mdma_channel0_sw_0, HAL_MDMA_XFER_ERROR_CB_ID, MDMA_TransferErrorCallback);
  HAL_MDMA_RegisterCallback(&hmdma_mdma_channel0_sw_0, HAL_MDMA_XFER_BLOCKCPLT_CB_ID, MDMA_TransferBlockCompleteCallback);
  /* USER CODE END mdma_channel0_sw_1 */

  /* Connect a node to the linked list */

  /* Make the linked list circular by connecting the last node to the first */
  if (HAL_MDMA_LinkedList_EnableCircularMode(&hmdma_mdma_channel0_sw_0) != HAL_OK)
  {
    Error_Handler();
  }

  /* MDMA interrupt initialization */
  /* MDMA_IRQn interrupt configuration */
  HAL_NVIC_SetPriority(MDMA_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(MDMA_IRQn);

}

/* USER CODE BEGIN 4 */
static void MDMA_TransferCompleteCallback(MDMA_HandleTypeDef *hmdma)
{
	__NOP();
}

static void MDMA_TransferErrorCallback(MDMA_HandleTypeDef *hmdma)
{
	__NOP();
}

static void MDMA_TransferBlockCompleteCallback(MDMA_HandleTypeDef *hmdma)
{
	__NOP();
	HAL_MDMA_GenerateSWRequest(&hmdma_mdma_channel0_sw_0);
}

//static void MDMA_TransferBufferCompleteCallback(MDMA_HandleTypeDef *hmdma)
//{
//	__NOP();
//}
/* USER CODE END 4 */

/* MPU Configuration */

void MPU_Config(void)
{
  MPU_Region_InitTypeDef MPU_InitStruct = {0};

  /* Disables the MPU */
  HAL_MPU_Disable();

  /** Initializes and configures the Region and the memory to be protected
  */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER0;
  MPU_InitStruct.BaseAddress = 0x0;
  MPU_InitStruct.Size = MPU_REGION_SIZE_4GB;
  MPU_InitStruct.SubRegionDisable = 0x87;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_NO_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);
  /* Enables the MPU */
  HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);

}

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @PAram  file: pointer to the source file name
  * @PAram  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */