Question
RTC init fails after CLOSED→OPEN regression on STM32H563 with TrustZone
Using on a STM32H563RI with trustzone for a secure bootloader and non-secure application. Both the secure and non-secure side were correctly working in OPEN state, and I did a test of going to a CLOSED state and regression back to OPEN with authenticated debug. After the regression, RTC_EnterInitMode(), times out trying to enter init mode and HAL_RTC_Init() fails. I tried the solution from this form post of calling HAL_PWR_EnableBkUpAccess() and that did not work.
Notes:
- Trustzone and the secure watermarks for the bootloader were reprogrammed in the option bytes after regression.
- RTC is LSI as its clock source.
- The call to HAL_RCCEx_PeriphCLKConfig() in HAL_RTC_MspInit() returns HAL_OK.
- The RTC pheripheral is marked non-secure.
- The code has not been changed since preforming the regression and was working previously.
The RTC Init Code and Clock configs are included below.
void MX_RTC_Init(void)
{
/* USER CODE BEGIN RTC_Init 0 */
/* USER CODE END RTC_Init 0 */
RTC_PrivilegeStateTypeDef privilegeState = {0};
/* USER CODE BEGIN RTC_Init 1 */
/* USER CODE END RTC_Init 1 */
/** Initialize RTC Only
*/
hrtc.Instance = RTC;
hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
hrtc.Init.AsynchPrediv = 127;
hrtc.Init.SynchPrediv = 255;
hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
hrtc.Init.OutPutPullUp = RTC_OUTPUT_PULLUP_NONE;
hrtc.Init.BinMode = RTC_BINARY_NONE;
if (HAL_RTC_Init(&hrtc) != HAL_OK)
{
Error_Handler();
}
privilegeState.rtcPrivilegeFull = RTC_PRIVILEGE_FULL_NO;
privilegeState.backupRegisterPrivZone = RTC_PRIVILEGE_BKUP_ZONE_NONE;
privilegeState.backupRegisterStartZone2 = RTC_BKP_DR0;
privilegeState.backupRegisterStartZone3 = RTC_BKP_DR0;
if (HAL_RTCEx_PrivilegeModeSet(&hrtc, &privilegeState) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN RTC_Init 2 */
/* USER CODE END RTC_Init 2 */
}
void HAL_RTC_MspInit(RTC_HandleTypeDef* rtcHandle)
{
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};
if(rtcHandle->Instance==RTC)
{
/* USER CODE BEGIN RTC_MspInit 0 */
/* USER CODE END RTC_MspInit 0 */
/** Initializes the peripherals clock
*/
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC;
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSI;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
/* RTC clock enable */
__HAL_RCC_RTC_ENABLE();
__HAL_RCC_RTCAPB_CLK_ENABLE();
/* USER CODE BEGIN RTC_MspInit 1 */
/* USER CODE END RTC_MspInit 1 */
}
}
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = { 0 };
RCC_ClkInitTypeDef RCC_ClkInitStruct = { 0 };
/** 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_LSI | RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.LSIState = RCC_LSI_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLL1_SOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = 6;
RCC_OscInitStruct.PLL.PLLN = 125;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 5;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_2;
RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1_VCORANGE_WIDE;
RCC_OscInitStruct.PLL.PLLFRACN = 0;
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_PCLK3;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
{
Error_Handler();
}
/** Configure the programming delay
*/
__HAL_FLASH_SET_PROGRAM_DELAY(FLASH_PROGRAMMING_DELAY_2);
}
void PeriphCommonClock_Config(void)
{
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = { 0 };
/** Initializes the peripherals clock
*/
PeriphClkInitStruct.PeriphClockSelection =
RCC_PERIPHCLK_USART1 | RCC_PERIPHCLK_USART2 | RCC_PERIPHCLK_SPI2 | RCC_PERIPHCLK_SPI3;
PeriphClkInitStruct.PLL2.PLL2Source = RCC_PLL2_SOURCE_HSE;
PeriphClkInitStruct.PLL2.PLL2M = 3;
PeriphClkInitStruct.PLL2.PLL2N = 20;
PeriphClkInitStruct.PLL2.PLL2P = 15;
PeriphClkInitStruct.PLL2.PLL2Q = 4;
PeriphClkInitStruct.PLL2.PLL2R = 2;
PeriphClkInitStruct.PLL2.PLL2RGE = RCC_PLL2_VCIRANGE_3;
PeriphClkInitStruct.PLL2.PLL2VCOSEL = RCC_PLL2_VCORANGE_WIDE;
PeriphClkInitStruct.PLL2.PLL2FRACN = 0;
PeriphClkInitStruct.PLL2.PLL2ClockOut = RCC_PLL2_DIVP | RCC_PLL2_DIVQ;
PeriphClkInitStruct.Usart1ClockSelection = RCC_USART1CLKSOURCE_PLL2Q;
PeriphClkInitStruct.Usart2ClockSelection = RCC_USART2CLKSOURCE_PLL2Q;
PeriphClkInitStruct.OspiClockSelection = RCC_OSPICLKSOURCE_PLL1Q;
PeriphClkInitStruct.Spi2ClockSelection = RCC_SPI2CLKSOURCE_PLL2P;
PeriphClkInitStruct.Spi3ClockSelection = RCC_SPI3CLKSOURCE_PLL2P;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
{
Error_Handler();
}
}