STM32H723 I2C MEM DMA not working

[Grozea.Ion]

Hi,

On a small project I am trying to use HAL_I2C_Mem_Read_DMA and AL_I2C_Mem_Write_DMA to get and send data to INA260 and SSD1306 without success.

In main i have:

MPU_Config();
SCB_EnableICache();
SCB_EnableDCache();

HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_DMA_Init();
MX_I2C1_Init();
if (INA260_Init() == HAL_OK) {
printf("INA260 initialized successfully.\n");
}

The MPU configuration is:

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 = 0x38000000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_4KB;
  MPU_InitStruct.SubRegionDisable = 0x0;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_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);

}

The I2c file is :

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    i2c.c
  * @brief   This file provides code for the configuration
  *          of the I2C instances.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2024 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 "i2c.h"

/* USER CODE BEGIN 0 */
volatile uint8_t i2c1_transfer_complete = 0;
uint8_t txBuffer[TX_LEN] __ATTR_DMA_BUFFER;
uint8_t rxBuffer[RX_LEN] __ATTR_DMA_BUFFER;
/* USER CODE END 0 */

I2C_HandleTypeDef hi2c1;
DMA_HandleTypeDef hdma_i2c1_rx;
DMA_HandleTypeDef hdma_i2c1_tx;

/* I2C1 init function */
void MX_I2C1_Init(void)
{

  /* USER CODE BEGIN I2C1_Init 0 */

  /* USER CODE END I2C1_Init 0 */

  /* USER CODE BEGIN I2C1_Init 1 */

  /* USER CODE END I2C1_Init 1 */
  hi2c1.Instance = I2C1;
  hi2c1.Init.Timing = 0x60404E72;
  hi2c1.Init.OwnAddress1 = 0;
  hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2 = 0;
  hi2c1.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
  hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c1) != HAL_OK)
  {
    Error_Handler();
  }

  /** Configure Analogue filter
  */
  if (HAL_I2CEx_ConfigAnalogFilter(&hi2c1, I2C_ANALOGFILTER_ENABLE) != HAL_OK)
  {
    Error_Handler();
  }

  /** Configure Digital filter
  */
  if (HAL_I2CEx_ConfigDigitalFilter(&hi2c1, 0) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN I2C1_Init 2 */

  /* USER CODE END I2C1_Init 2 */

}

void HAL_I2C_MspInit(I2C_HandleTypeDef* i2cHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
  if(i2cHandle->Instance==I2C1)
  {
  /* USER CODE BEGIN I2C1_MspInit 0 */

  /* USER CODE END I2C1_MspInit 0 */

  /** Initializes the peripherals clock
  */
    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_I2C1;
    PeriphClkInitStruct.I2c123ClockSelection = RCC_I2C1235CLKSOURCE_D2PCLK1;
    if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
    {
      Error_Handler();
    }

    __HAL_RCC_GPIOB_CLK_ENABLE();
    /**I2C1 GPIO Configuration
    PB8     ------> I2C1_SCL
    PB9     ------> I2C1_SDA
    */
    GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_9;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_OD;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    GPIO_InitStruct.Alternate = GPIO_AF4_I2C1;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

    /* I2C1 clock enable */
    __HAL_RCC_I2C1_CLK_ENABLE();

    /* I2C1 DMA Init */
    /* I2C1_RX Init */
    hdma_i2c1_rx.Instance = DMA1_Stream6;
    hdma_i2c1_rx.Init.Request = DMA_REQUEST_I2C1_RX;
    hdma_i2c1_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;
    hdma_i2c1_rx.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_i2c1_rx.Init.MemInc = DMA_MINC_ENABLE;
    hdma_i2c1_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
    hdma_i2c1_rx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
    hdma_i2c1_rx.Init.Mode = DMA_NORMAL;
    hdma_i2c1_rx.Init.Priority = DMA_PRIORITY_LOW;
    hdma_i2c1_rx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
    if (HAL_DMA_Init(&hdma_i2c1_rx) != HAL_OK)
    {
      Error_Handler();
    }

    __HAL_LINKDMA(i2cHandle,hdmarx,hdma_i2c1_rx);

    /* I2C1_TX Init */
    hdma_i2c1_tx.Instance = DMA1_Stream7;
    hdma_i2c1_tx.Init.Request = DMA_REQUEST_I2C1_TX;
    hdma_i2c1_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;
    hdma_i2c1_tx.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_i2c1_tx.Init.MemInc = DMA_MINC_ENABLE;
    hdma_i2c1_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
    hdma_i2c1_tx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
    hdma_i2c1_tx.Init.Mode = DMA_NORMAL;
    hdma_i2c1_tx.Init.Priority = DMA_PRIORITY_LOW;
    hdma_i2c1_tx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
    if (HAL_DMA_Init(&hdma_i2c1_tx) != HAL_OK)
    {
      Error_Handler();
    }

    __HAL_LINKDMA(i2cHandle,hdmatx,hdma_i2c1_tx);

    /* I2C1 interrupt Init */
    HAL_NVIC_SetPriority(I2C1_EV_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(I2C1_EV_IRQn);
    HAL_NVIC_SetPriority(I2C1_ER_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(I2C1_ER_IRQn);
  /* USER CODE BEGIN I2C1_MspInit 1 */

  /* USER CODE END I2C1_MspInit 1 */
  }
}

void HAL_I2C_MspDeInit(I2C_HandleTypeDef* i2cHandle)
{

  if(i2cHandle->Instance==I2C1)
  {
  /* USER CODE BEGIN I2C1_MspDeInit 0 */

  /* USER CODE END I2C1_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_I2C1_CLK_DISABLE();

    /**I2C1 GPIO Configuration
    PB8     ------> I2C1_SCL
    PB9     ------> I2C1_SDA
    */
    HAL_GPIO_DeInit(GPIOB, GPIO_PIN_8);

    HAL_GPIO_DeInit(GPIOB, GPIO_PIN_9);

    /* I2C1 DMA DeInit */
    HAL_DMA_DeInit(i2cHandle->hdmarx);
    HAL_DMA_DeInit(i2cHandle->hdmatx);

    /* I2C1 interrupt Deinit */
    HAL_NVIC_DisableIRQ(I2C1_EV_IRQn);
    HAL_NVIC_DisableIRQ(I2C1_ER_IRQn);
  /* USER CODE BEGIN I2C1_MspDeInit 1 */

  /* USER CODE END I2C1_MspDeInit 1 */
  }
}

/* USER CODE BEGIN 1 */
HAL_StatusTypeDef I2C_DMA_Write_MEM(uint16_t DevAddress, uint16_t MemAddress, uint16_t MemAddSize, uint16_t Size) {
		// Clean the cache for the transmit buffer to ensure coherency
    //SCB_CleanDCache_by_Addr((uint32_t*)pData, Size);
    // Start the I2C DMA memory write operation
    HAL_StatusTypeDef status = HAL_I2C_Mem_Write_DMA(&hi2c1, DevAddress, MemAddress, MemAddSize, txBuffer, Size);
    
    if (status != HAL_OK) {
        return status;
    }

//    // Track the start time for timeout management
//    uint32_t tickstart = HAL_GetTick();
//    
//    // Wait for the transfer to complete with timeout mechanism
//    while (i2c1_transfer_complete == 0) {
//        // Check if timeout is reached
//        if ((HAL_GetTick() - tickstart) > TIME_OUT) {
//            return HAL_TIMEOUT;
//        }
//    } 
    return HAL_OK;
}

HAL_StatusTypeDef I2C_DMA_Read_MEM(uint16_t DevAddress, uint16_t MemAddress, uint16_t MemAddSize){
		// Invalidate the cache for the receive buffer to ensure we get fresh data
    //SCB_InvalidateDCache_by_Addr((uint32_t*)pData, Size);
    // Start the I2C DMA memory read operation
    HAL_StatusTypeDef status = HAL_I2C_Mem_Read_DMA(&hi2c1, DevAddress, MemAddress, MemAddSize, rxBuffer, RX_LEN);

    if (status != HAL_OK) {
        return status;
    }

//    // Track the start time for timeout management
//    uint32_t tickstart = HAL_GetTick();
//    // Wait for the transfer to complete with timeout mechanism
//    while (i2c1_transfer_complete == 0) {
//        // Check if timeout is reached
//        if ((HAL_GetTick() - tickstart) > TIME_OUT) {
//            return HAL_TIMEOUT;
//        }
//    }

    return HAL_OK;
}

void HAL_I2C_MasterTxCpltCallback(I2C_HandleTypeDef *hi2c) {
    if (hi2c->Instance == I2C1) {
        i2c1_transfer_complete = 1;  // Mark transfer as complete
    }
}

void HAL_I2C_MasterRxCpltCallback(I2C_HandleTypeDef *hi2c) {
    if (hi2c->Instance == I2C1) {
        i2c1_transfer_complete = 1;  // Mark transfer as complete
    }
}

void HAL_I2C_ErrorCallback(I2C_HandleTypeDef *hi2c) {
    if (hi2c->Instance == I2C1) {
        i2c1_transfer_complete = 1;  // Mark as complete even in case of error
        // Additional error handling code can be added here
    }
}
/* USER CODE END 1 */

In i2c.h i have:

/* USER CODE BEGIN Includes */
extern volatile uint8_t i2c1_transfer_complete;
/* USER CODE END Includes */

extern I2C_HandleTypeDef hi2c1;

/* USER CODE BEGIN Private defines */
#define __ATTR_DMA_BUFFER __attribute__ ((section(".dma_buffer"))) __attribute__ ((aligned (4)))

#define TIME_OUT 100
#define TX_LEN 1024
#define RX_LEN 2

extern uint8_t txBuffer[TX_LEN] __ATTR_DMA_BUFFER;
extern uint8_t rxBuffer[RX_LEN] __ATTR_DMA_BUFFER;

/* USER CODE END Private defines */

void MX_I2C1_Init(void);

/* USER CODE BEGIN Prototypes */
HAL_StatusTypeDef I2C_DMA_Write_MEM(uint16_t DevAddress, uint16_t MemAddress, uint16_t MemAddSize, uint16_t Size);
HAL_StatusTypeDef I2C_DMA_Read_MEM(uint16_t DevAddress, uint16_t MemAddress, uint16_t MemAddSize);
/* USER CODE END Prototypes */

In Ina260.c i have : 

// Track energy consumption
static uint32_t start_time_ms;
static float total_energy_Wh = 0.0f;
static INA260_Config myConfig = {.Value = DEFAULT_CONFIG};
static INA260_Mask myMask = {.Value = DEFAULT_MASK};

extern uint8_t txBuffer[TX_LEN] __ATTR_DMA_BUFFER;
extern uint8_t rxBuffer[RX_LEN] __ATTR_DMA_BUFFER;
// Helper function to write a 16-bit register (MSB first)
// Original implementation commented for reference

/*
static HAL_StatusTypeDef write_register(uint8_t reg, uint16_t value) {
    uint8_t data[BUFFER_LEN];

    // Send MSB first, followed by LSB
    data[0] = (uint8_t)(value >> 8);  // MSB
    data[1] = (uint8_t)(value & 0xFF);  // LSB

    return HAL_I2C_Mem_Write(&hi2c1, INA260_I2C_ADDRESS, reg, I2C_MEMADD_SIZE_8BIT, data, BUFFER_LEN, TIMEOUT_MS);
}
*/


// Updated write_register using DMA
static HAL_StatusTypeDef write_register(uint8_t reg, uint16_t value) {
    // Send MSB first, followed by LSB
    txBuffer[0] = (uint8_t)(value >> 8);  // MSB
    txBuffer[1] = (uint8_t)(value & 0xFF);  // LSB

    // Use the global I2C DMA function for writing
    return I2C_DMA_Write_MEM((uint16_t)INA260_I2C_ADDRESS, reg, I2C_MEMADD_SIZE_8BIT, BUFFER_LEN);
}

// Helper function to read a 16-bit register (MSB first)
// Original implementation commented for reference
/*
static HAL_StatusTypeDef read_register(uint8_t reg, uint16_t *value) {
    uint8_t data[BUFFER_LEN];
    HAL_StatusTypeDef status;

    // First write the register address to read from
    status = HAL_I2C_Mem_Read(&hi2c1, INA260_I2C_ADDRESS, reg, I2C_MEMADD_SIZE_8BIT, data, BUFFER_LEN, TIMEOUT_MS);

    if (status == HAL_OK) {
        // Reconstruct the 16-bit value (MSB first)
        *value = (data[0] << 8) | data[1];  // MSB first, then LSB
    }

    return status;
}
*/

// Updated read_register using DMA
static HAL_StatusTypeDef read_register(uint8_t reg, uint16_t *value) {
    HAL_StatusTypeDef status;
    // Use the global I2C DMA function for reading
    status = I2C_DMA_Read_MEM((uint16_t)INA260_I2C_ADDRESS, reg, I2C_MEMADD_SIZE_8BIT);

    if (status == HAL_OK) {
        // Reconstruct the 16-bit value (MSB first)
        *value = (rxBuffer[0] << 8) | rxBuffer[1];  // MSB first, then LSB
    }

    return status;
}

// Initialize INA260
HAL_StatusTypeDef INA260_Init(void) {
    uint16_t mfg_id, dev_id;
    HAL_StatusTypeDef status;

    // Check manufacturer and device IDs
    status = INA260_GetManufacturerID(&mfg_id);
    if (status != HAL_OK || mfg_id != DEFAULT_MFG_ID) return HAL_ERROR;

    status = INA260_GetDieID(&dev_id);
    if (status != HAL_OK || dev_id != DEFAULT_DEV_ID) return HAL_ERROR;

    INA260_Reset();
    
    // Set default configuration (continuous current and voltage measurement)
    status = INA260_SetConfig(&myConfig);
    if (status != HAL_OK) return HAL_ERROR;

    // Set mask/enable configuration
    status = INA260_SetMaskEnable(&myMask);
    if (status != HAL_OK) return HAL_ERROR;

    // Read back the configuration to ensure it is set correctly
    status = INA260_GetConfig(&myConfig);
    status = INA260_GetMaskEnable(&myMask);
    return status;
}

Now, I do not get any error and also the HAL_I2C_MasterTxCpltCallback, HAL_I2C_MasterRxCpltCallback and HAL_I2C_ErrorCallback are not triggered.

The data I receive in the init of INA260 is not correct, I have to add the fact that the code is working in non DMA mode.

My scatter file is : 

LR_IROM1 0x08000000 0x00100000  {    ; load region size_region
  ER_IROM1 0x08000000 0x00100000  {  ; load address = execution address
   *.o (RESET, +First)
   *(InRoot$$Sections)
   .ANY (+RO)
   .ANY (+XO)
  }
  RW_IRAM1 0x20000000 0x00020000  {  ; RW data
   .ANY (+RW +ZI)
  }
  RW_IRAM2 0x24000000 0x00020000  {
   .ANY (+RW +ZI)
  }
  ; Added new region
  DMA_BUFFER 0x38000000 0x00001000 {
  *(.dma_buffer)
  }
}

Any idea how to fix the issue? Thank you.

[TDK · Accepted solution]

DMA happens in the background. You need to wait for the operation to complete before using the values. The HAL_I2C_Mem_Read_DMA function only starts the process. Data isn't in the receiving buffer immediately after that.

[Grozea.Ion]

Thank you for yor reply, you are right.