bootloader for stm32f030k6t6

[jdo]

i am trying to make a bootloader for a stm32f030k6t6, i was reading the AN4325 application note, from what i understood that i can only have a USART bootloader on pins PA14/PA15 or PA9/PA10, and i have a bluetooth connected on the uart1 serial which are different pins from PA14/PA15--PA9/PA10, i wanted to know if it is possible to use the bluetooth to make OTA bottloader. and also I have many doubts about the RAM memory, since it is 4k, it starts at address 0x2000 0000, then I must make a division of memory for the bottloader initially I am placing 0x200100, I do not know if it is right to define that amount.

Translated with www.DeepL.com/Translator (free version)

[jdo]

/*
******************************************************************************
**
** @file : LinkerScript.ld
**
** @author : Auto-generated by STM32CubeIDE
**
** @brief : Linker script for STM32F030K6Tx Device from STM32F0 series
** 32Kbytes FLASH
** 4Kbytes RAM
**
** Set heap size, stack size and stack location according
** to application requirements.
**
** Set memory bank area and size if external memory is used
**
** Target : STMicroelectronics STM32
**
** Distribution: The file is distributed as is, without any warranty
** of any kind.
**
******************************************************************************
** @attention
**
** Copyright (c) 2022 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.
**
******************************************************************************
*/
 
/* Entry Point */
ENTRY(Reset_Handler)
 
/* Highest address of the user mode stack */
_estack = ORIGIN(RAM) + LENGTH(RAM); /* end of "RAM" Ram type memory */
 
_Min_Heap_Size = 0x200 ; /* required amount of heap */
_Min_Stack_Size = 0x400 ; /* required amount of stack */
 
/* Memories definition */
MEMORY
{
 RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 4K
 FLASH (rx) : ORIGIN = 0x8000000, LENGTH = 32K
}
 
/* Sections */
SECTIONS
{
 /* The startup code into "FLASH" Rom type memory */
 .isr_vector :
 {
 . = ALIGN(4);
 KEEP(*(.isr_vector)) /* Startup code */
 . = ALIGN(4);
 } >FLASH
 
 .myBufBlockRAM 0x200100:
 {
 	KEEP(*(myBufSectionkRAM)) /* MANTIENE MI VARIABLE SIEMPRE QUE NO ES REFERENCIADA */
 
 }>RAM
 
 /* The program code and other data into "FLASH" Rom type memory */
 .text :
 {
 . = ALIGN(4);
 *(.text) /* .text sections (code) */
 *(.text*) /* .text* sections (code) */
 *(.glue_7) /* glue arm to thumb code */
 *(.glue_7t) /* glue thumb to arm code */
 *(.eh_frame)
 
 KEEP (*(.init))
 KEEP (*(.fini))
 
 . = ALIGN(4);
 _etext = .; /* define a global symbols at end of code */
 } >FLASH
 
 /* Constant data into "FLASH" Rom type memory */
 .rodata :
 {
 . = ALIGN(4);
 *(.rodata) /* .rodata sections (constants, strings, etc.) */
 *(.rodata*) /* .rodata* sections (constants, strings, etc.) */
 . = ALIGN(4);
 } >FLASH
 
 .ARM.extab : {
 . = ALIGN(4);
 *(.ARM.extab* .gnu.linkonce.armextab.*)
 . = ALIGN(4);
 } >FLASH
 
 .ARM : {
 . = ALIGN(4);
 __exidx_start = .;
 *(.ARM.exidx*)
 __exidx_end = .;
 . = ALIGN(4);
 } >FLASH
 
 .preinit_array :
 {
 . = ALIGN(4);
 PROVIDE_HIDDEN (__preinit_array_start = .);
 KEEP (*(.preinit_array*))
 PROVIDE_HIDDEN (__preinit_array_end = .);
 . = ALIGN(4);
 } >FLASH
 
 .init_array :
 {
 . = ALIGN(4);
 PROVIDE_HIDDEN (__init_array_start = .);
 KEEP (*(SORT(.init_array.*)))
 KEEP (*(.init_array*))
 PROVIDE_HIDDEN (__init_array_end = .);
 . = ALIGN(4);
 } >FLASH
 
 .fini_array :
 {
 . = ALIGN(4);
 PROVIDE_HIDDEN (__fini_array_start = .);
 KEEP (*(SORT(.fini_array.*)))
 KEEP (*(.fini_array*))
 PROVIDE_HIDDEN (__fini_array_end = .);
 . = ALIGN(4);
 } >FLASH
 
 /* Used by the startup to initialize data */
 _sidata = LOADADDR(.data);
 
 /* Initialized data sections into "RAM" Ram type memory */
 .data :
 {
 . = ALIGN(4);
 _sdata = .; /* create a global symbol at data start */
 *(.data) /* .data sections */
 *(.data*) /* .data* sections */
 *(.RamFunc) /* .RamFunc sections */
 *(.RamFunc*) /* .RamFunc* sections */
 
 . = ALIGN(4);
 _edata = .; /* define a global symbol at data end */
 
 } >RAM AT> FLASH
 
 /* Uninitialized data section into "RAM" Ram type memory */
 . = ALIGN(4);
 .bss :
 {
 /* This is used by the startup in order to initialize the .bss section */
 _sbss = .; /* define a global symbol at bss start */
 __bss_start__ = _sbss;
 *(.bss)
 *(.bss*)
 *(COMMON)
 
 . = ALIGN(4);
 _ebss = .; /* define a global symbol at bss end */
 __bss_end__ = _ebss;
 } >RAM
 
 /* User_heap_stack section, used to check that there is enough "RAM" Ram type memory left */
 ._user_heap_stack :
 {
 . = ALIGN(8);
 PROVIDE ( end = . );
 PROVIDE ( _end = . );
 . = . + _Min_Heap_Size;
 . = . + _Min_Stack_Size;
 . = ALIGN(8);
 } >RAM
 
 /* Remove information from the compiler libraries */
 /DISCARD/ :
 {
 libc.a ( * )
 libm.a ( * )
 libgcc.a ( * )
 }
 
 .ARM.attributes 0 : { *(.ARM.attributes) }
}

[jdo]

in the linker, i write:

.myBufBlockRAM 0x200100:

{

KEEP(*(myBufSectionkRAM)) /* MANTIENE MI VARIABLE SIEMPRE QUE NO ES REFERENCIADA */

}>RAM

[jdo]

in the main:

/* USER CODE END PV */
unsigned char __attribute__((section(".myBufSectionkRAM"))) buf_ram[128];

/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file : main.c
 * @brief : Main program body
 ******************************************************************************
 * @attention
 *
 * Copyright (c) 2022 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 */
/* USER CODE END PD */
 
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
 
/* USER CODE END PM */
 
/* Private variables ---------------------------------------------------------*/
 UART_HandleTypeDef huart1;
DMA_HandleTypeDef hdma_usart1_rx;
 
/* USER CODE BEGIN PV */
 
/* USER CODE END PV */
unsigned char __attribute__((section(".myBufSectionkRAM"))) buf_ram[128];
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_DMA_Init(void);
static void MX_USART1_UART_Init(void);
/* USER CODE BEGIN PFP */
 
/* 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 */
 
 /* USER CODE END 1 */
 
 /* MCU Configuration--------------------------------------------------------*/
 
 /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
 HAL_Init();
 
 /* 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_GPIO_Init();
 MX_DMA_Init();
 MX_USART1_UART_Init();
 /* USER CODE BEGIN 2 */
 
 /* 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};
 RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};
 
 /** 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_ON;
 RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
 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_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
 
 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
 {
 Error_Handler();
 }
 PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART1;
 PeriphClkInit.Usart1ClockSelection = RCC_USART1CLKSOURCE_PCLK1;
 if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
 {
 Error_Handler();
 }
}
 
/**
 * @brief USART1 Initialization Function
 * @param None
 * @retval None
 */
static void MX_USART1_UART_Init(void)
{
 
 /* USER CODE BEGIN USART1_Init 0 */
 
 /* USER CODE END USART1_Init 0 */
 
 /* USER CODE BEGIN USART1_Init 1 */
 
 /* USER CODE END USART1_Init 1 */
 huart1.Instance = USART1;
 huart1.Init.BaudRate = 115200;
 huart1.Init.WordLength = UART_WORDLENGTH_8B;
 huart1.Init.StopBits = UART_STOPBITS_1;
 huart1.Init.Parity = UART_PARITY_NONE;
 huart1.Init.Mode = UART_MODE_TX_RX;
 huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
 huart1.Init.OverSampling = UART_OVERSAMPLING_16;
 huart1.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
 huart1.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
 if (HAL_UART_Init(&huart1) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN USART1_Init 2 */
 
 /* USER CODE END USART1_Init 2 */
 
}
 
/**
 * Enable DMA controller clock
 */
static void MX_DMA_Init(void)
{
 
 /* DMA controller clock enable */
 __HAL_RCC_DMA1_CLK_ENABLE();
 
 /* DMA interrupt init */
 /* DMA1_Channel2_3_IRQn interrupt configuration */
 HAL_NVIC_SetPriority(DMA1_Channel2_3_IRQn, 0, 0);
 HAL_NVIC_EnableIRQ(DMA1_Channel2_3_IRQn);
 
}
 
/**
 * @brief GPIO Initialization Function
 * @param None
 * @retval None
 */
static void MX_GPIO_Init(void)
{
 
 /* GPIO Ports Clock Enable */
 __HAL_RCC_GPIOA_CLK_ENABLE();
 
}
 
/* USER CODE BEGIN 4 */
 
/* USER CODE END 4 */
 
/**
 * @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 */

[jdo]

i am using this tutorial stm: (332) How to Create a Super Simple Bootloader, Part 1: Getting Started - YouTube

[jdo]

[Tesla DeLorean]

Not sure why you need to allocate a buffer in that way, but surely needs to be 0x20000100 not 0x200100​

[jdo]

I AM DOING THIS TUTORIAL ST: (332) How to Create a Super Simple Bootloader, Part 1: Getting Started - YouTube,

What way do you recommend to make a simple bootloader?

how do I determine how many bytes there are from 0x2000 0000 to 0x20000100?

I'm sorry for my ignorance, I'm not an expert in stm32, some time ago I programmed in c with microchip, but I'm programming a board with stm32, and I like to discover.

[Tesla DeLorean]

I'm not sure this stuff is super STM32 specific. This is compilers, assemblers, linkers and loaders

Man that video is painful. Often it's better to use a robot to narrate a script.

Why's he put a section smack in the middle of his loader, loader 12KB, dumps stuff at 4K (0x1000)

>>how do I determine how many bytes there are from 0x2000 0000 to 0x20000100?

Used, or physically?

0x100 -> 256 bytes

Still it says 0x20000100, not 0x200100. The basis of RAM in Cortex-Mx parts is 0x20000000, FLASH 0x08000000

He's allocating space for variables/structures you want in common between the two.

You could advance the basis of RAM in the linker script, and use a structure via a pointer.

Are you sharing a lot of information between the two? Usually apps are free standing, and the loader basically just needs to validate them, and provide a means/method of updating or disaster recovery.

The CM0 gets more involved as you can't relocate the Vector Table, other than remapping RAM, and in this case you want to carve out a section for the Vector Table at 0x20000000..0x2000007F to accomodate a copy of the table, and then remap/shadow this memory at the 0x00000000 address.

MEMORY
{
 VECTORRAM (xrw) : ORIGIN = 0x20000000, LENGTH = 128
 RAM (xrw) : ORIGIN = 0x20000080, LENGTH = 4K - 128
 FLASH (rx) : ORIGIN = 0x8000000, LENGTH = 32K
}

[jdo]

in the tutorial st youtube i view this