Initialization Functions

Initialization and Configuration Functions. More...

Functions
HAL_StatusTypeDef	HAL_FIREWALL_Config (FIREWALL_InitTypeDef *fw_init)
	Initialize the Firewall according to the FIREWALL_InitTypeDef structure parameters. More...
void	HAL_FIREWALL_GetConfig (FIREWALL_InitTypeDef *fw_config)
	Retrieve the Firewall configuration. More...
void	HAL_FIREWALL_EnableFirewall (void)
	Enable FIREWALL. More...
void	HAL_FIREWALL_EnablePreArmFlag (void)
	Enable FIREWALL pre arm. More...
void	HAL_FIREWALL_DisablePreArmFlag (void)
	Disable FIREWALL pre arm. More...

Detailed Description

Initialization and Configuration Functions.

===============================================================================
            ##### Initialization and Configuration functions #####
 ===============================================================================
    [..]
    This subsection provides the functions allowing to initialize the Firewall.
    Initialization is done by HAL_FIREWALL_Config():

      (+) Enable the Firewall clock thru __HAL_RCC_FIREWALL_CLK_ENABLE() macro.

      (+) Set the protected code segment address start and length.

      (+) Set the protected non-volatile and/or volatile data segments
          address starts and lengths if applicable.

      (+) Set the volatile data segment execution and sharing status.

      (+) Length must be set to 0 for an unprotected segment.

Function Documentation

HAL_FIREWALL_Config()

HAL_StatusTypeDef HAL_FIREWALL_Config

(

FIREWALL_InitTypeDef *

fw_init

)

Initialize the Firewall according to the FIREWALL_InitTypeDef structure parameters.

Parameters

fw_init

Firewall initialization structure

Note

The API returns HAL_ERROR if the Firewall is already enabled.

Return values

HAL

status

Definition at line 103 of file stm32l4xx_hal_firewall.c.

{
  /* Check the Firewall initialization structure allocation */
  if(fw_init == NULL)
  {
    return HAL_ERROR;
  }

  /* Enable Firewall clock */
  __HAL_RCC_FIREWALL_CLK_ENABLE();

  /* Make sure that Firewall is not enabled already */
  if (__HAL_FIREWALL_IS_ENABLED() != RESET)
  {
    return HAL_ERROR;
  }

  /* Check Firewall configuration addresses and lengths when segment is protected */
  /* Code segment */
  if (fw_init->CodeSegmentLength != 0U)
  {
    assert_param(IS_FIREWALL_CODE_SEGMENT_ADDRESS(fw_init->CodeSegmentStartAddress));
    assert_param(IS_FIREWALL_CODE_SEGMENT_LENGTH(fw_init->CodeSegmentStartAddress, fw_init->CodeSegmentLength));
    /* Make sure that NonVDataSegmentLength is properly set to prevent code segment access */
    if (fw_init->NonVDataSegmentLength < 0x100U)
    {
      return HAL_ERROR;
    }
  }
  /* Non volatile data segment */
  if (fw_init->NonVDataSegmentLength != 0U)
  {
    assert_param(IS_FIREWALL_NONVOLATILEDATA_SEGMENT_ADDRESS(fw_init->NonVDataSegmentStartAddress));
    assert_param(IS_FIREWALL_NONVOLATILEDATA_SEGMENT_LENGTH(fw_init->NonVDataSegmentStartAddress, fw_init->NonVDataSegmentLength));
  }
  /* Volatile data segment */
  if (fw_init->VDataSegmentLength != 0U)
  {
    assert_param(IS_FIREWALL_VOLATILEDATA_SEGMENT_ADDRESS(fw_init->VDataSegmentStartAddress));
    assert_param(IS_FIREWALL_VOLATILEDATA_SEGMENT_LENGTH(fw_init->VDataSegmentStartAddress, fw_init->VDataSegmentLength));
  }

  /* Check Firewall Configuration Register parameters */
  assert_param(IS_FIREWALL_VOLATILEDATA_EXECUTE(fw_init->VolatileDataExecution));
  assert_param(IS_FIREWALL_VOLATILEDATA_SHARE(fw_init->VolatileDataShared));


   /* Configuration */

  /* Protected code segment start address configuration */
  WRITE_REG(FIREWALL->CSSA, (FW_CSSA_ADD & fw_init->CodeSegmentStartAddress));
    /* Protected code segment length configuration */
  WRITE_REG(FIREWALL->CSL, (FW_CSL_LENG & fw_init->CodeSegmentLength));

  /* Protected non volatile data segment start address configuration */
  WRITE_REG(FIREWALL->NVDSSA, (FW_NVDSSA_ADD & fw_init->NonVDataSegmentStartAddress));
    /* Protected non volatile data segment length configuration */
  WRITE_REG(FIREWALL->NVDSL, (FW_NVDSL_LENG & fw_init->NonVDataSegmentLength));

  /* Protected volatile data segment start address configuration */
  WRITE_REG(FIREWALL->VDSSA, (FW_VDSSA_ADD & fw_init->VDataSegmentStartAddress));
    /* Protected volatile data segment length configuration */
  WRITE_REG(FIREWALL->VDSL, (FW_VDSL_LENG & fw_init->VDataSegmentLength));

  /* Set Firewall Configuration Register VDE and VDS bits
     (volatile data execution and shared configuration) */
  MODIFY_REG(FIREWALL->CR, FW_CR_VDS|FW_CR_VDE, fw_init->VolatileDataExecution|fw_init->VolatileDataShared);

  return HAL_OK;
}

HAL_FIREWALL_DisablePreArmFlag()

void HAL_FIREWALL_DisablePreArmFlag

(

void

)

Disable FIREWALL pre arm.

Note

When FPA bit is reset, any code executed outside the protected segment when the Firewall is opened will generate a system reset.

This API provides the same service as __HAL_FIREWALL_PREARM_DISABLE() macro but can't be executed inside a code area protected by the Firewall.

When the Firewall is disabled, user can resort to HAL_FIREWALL_EnablePreArmFlag() API any time.

When the Firewall is enabled and NVDSL register is equal to 0 (that is, when the non volatile data segment is not defined), ** this API can be executed when the Firewall is closed ** when the Firewall is opened, user should resort to __HAL_FIREWALL_PREARM_DISABLE() macro instead

When the Firewall is enabled and NVDSL register is different from 0 (that is, when the non volatile data segment is defined) ** FW_CR register can be accessed only when the Firewall is opened: user should resort to __HAL_FIREWALL_PREARM_DISABLE() macro instead.

Return values

None

Definition at line 272 of file stm32l4xx_hal_firewall.c.

{
  /* Clear FPA bit */
  CLEAR_BIT(FIREWALL->CR, FW_CR_FPA);
}

HAL_FIREWALL_EnableFirewall()

void HAL_FIREWALL_EnableFirewall

(

void

)

Enable FIREWALL.

Note

Firewall is enabled in clearing FWDIS bit of SYSCFG CFGR1 register. Once enabled, the Firewall cannot be disabled by software. Only a system reset can set again FWDIS bit.

Return values

None

Definition at line 221 of file stm32l4xx_hal_firewall.c.

{
  /* Clears FWDIS bit of SYSCFG CFGR1 register */
  CLEAR_BIT(SYSCFG->CFGR1, SYSCFG_CFGR1_FWDIS);

}

HAL_FIREWALL_EnablePreArmFlag()

void HAL_FIREWALL_EnablePreArmFlag

(

void

)

Enable FIREWALL pre arm.

Note

When FPA bit is set, any code executed outside the protected segment will close the Firewall.

This API provides the same service as __HAL_FIREWALL_PREARM_ENABLE() macro but can't be executed inside a code area protected by the Firewall.

When the Firewall is disabled, user can resort to HAL_FIREWALL_EnablePreArmFlag() API any time.

When the Firewall is enabled and NVDSL register is equal to 0 (that is, when the non volatile data segment is not defined), ** this API can be executed when the Firewall is closed ** when the Firewall is opened, user should resort to __HAL_FIREWALL_PREARM_ENABLE() macro instead

When the Firewall is enabled and NVDSL register is different from 0 (that is, when the non volatile data segment is defined) ** FW_CR register can be accessed only when the Firewall is opened: user should resort to __HAL_FIREWALL_PREARM_ENABLE() macro instead.

Return values

None

Definition at line 246 of file stm32l4xx_hal_firewall.c.

{
  /* Set FPA bit */
  SET_BIT(FIREWALL->CR, FW_CR_FPA);
}

HAL_FIREWALL_GetConfig()

void HAL_FIREWALL_GetConfig

(

FIREWALL_InitTypeDef *

fw_config

)

Retrieve the Firewall configuration.

Parameters

fw_config

Firewall configuration, type is same as initialization structure

Note

This API can't be executed inside a code area protected by the Firewall when the Firewall is enabled

If NVDSL register is different from 0, that is, if the non volatile data segment is defined, this API can't be executed when the Firewall is enabled.

User should resort to __HAL_FIREWALL_GET_PREARM() macro to retrieve FPA bit status

Return values

None

Definition at line 184 of file stm32l4xx_hal_firewall.c.

{

  /* Enable Firewall clock, in case no Firewall configuration has been carried
     out up to this point */
  __HAL_RCC_FIREWALL_CLK_ENABLE();

  /* Retrieve code segment protection setting */
  fw_config->CodeSegmentStartAddress = (READ_REG(FIREWALL->CSSA) & FW_CSSA_ADD);
  fw_config->CodeSegmentLength = (READ_REG(FIREWALL->CSL) & FW_CSL_LENG);

  /* Retrieve non volatile data segment protection setting */
  fw_config->NonVDataSegmentStartAddress = (READ_REG(FIREWALL->NVDSSA) & FW_NVDSSA_ADD);
  fw_config->NonVDataSegmentLength = (READ_REG(FIREWALL->NVDSL) & FW_NVDSL_LENG);

  /* Retrieve volatile data segment protection setting */
  fw_config->VDataSegmentStartAddress = (READ_REG(FIREWALL->VDSSA) & FW_VDSSA_ADD);
  fw_config->VDataSegmentLength = (READ_REG(FIREWALL->VDSL) & FW_VDSL_LENG);

  /* Retrieve volatile data execution setting */
  fw_config->VolatileDataExecution = (READ_REG(FIREWALL->CR) & FW_CR_VDE);

  /* Retrieve volatile data shared setting */
  fw_config->VolatileDataShared = (READ_REG(FIREWALL->CR) & FW_CR_VDS);

  return;
}