MX 10 and H563: Generating bad LL code for MPU region ?

[Nikita91]

When I generate code for the MPU region 0 wit HAL I get:

void MPU_Config(void)
{
  MPU_Region_InitTypeDef MPU_InitStruct = {0};
  MPU_Attributes_InitTypeDef MPU_AttributesInit = {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 = 0x08fff800;
  MPU_InitStruct.LimitAddress = 0x08fff900;
  MPU_InitStruct.AttributesIndex = MPU_ATTRIBUTES_NUMBER0;
  MPU_InitStruct.AccessPermission = MPU_REGION_ALL_RO;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_OUTER_SHAREABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);
  MPU_AttributesInit.Number = MPU_REGION_NUMBER0;
  MPU_AttributesInit.Attributes = MPU_DEVICE_nGnRnE | MPU_WRITE_THROUGH
                              | MPU_TRANSIENT | MPU_NO_ALLOCATE;

  HAL_MPU_ConfigMemoryAttributes(&MPU_AttributesInit);
  /* Enables the MPU */
  HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);
}

OK.

With the exact same configuration, when I switch to LL I get:

void MPU_Config(void)
{
  /* Disables the MPU */
  LL_MPU_Disable();

  /** Initializes and configures the Region and the memory to be protected
  */
  LL_MPU_ConfigRegion(LL_MPU_REGION_NUMBER0, LL_MPU_INSTRUCTION_ACCESS_DISABLE, LL_MPU_ATTRIBUTES_NUMBER0, 0x08fff800, 0x08fff900);
  LL_MPU_EnableRegion(LL_MPU_REGION_NUMBER0);
  LL_MPU_ConfigAttributes(LL_MPU_ATTRIBUTES_NUMBER0, LL_MPU_DEVICE_nGnRnE | LL_MPU_WRITE_THROUGH
                              | LL_MPU_TRANSIENT | LL_MPU_NO_ALLOCATE);
  /* Enables the MPU */
  LL_MPU_Enable(LL_MPU_CTRL_PRIVILEGED_DEFAULT);
}

I think there are not equivalent. There is a missing :

 | LL_MPU_REGION_ALL_RO | LL_MPU_ACCESS_OUTER_SHAREABLE

in the 2nd parameter of LL_MPU_ConfigRegion().

Is this true?

[Semer CHERNI · Accepted solution]

Hello @Nikita91 

First let me thank you for posting.

In fact you are right, I made the test adding the missing code, and only then I get the same MPU registers configuration done by the HAL generated code.

The issue is raised internally for analysis and future fix (169120: this is an internal ticket number)

KR,
Semer.