betaflight/src/link/stm32_flash.ld

/*
*****************************************************************************
**
**  File        : stm32_flash.ld
**
**  Abstract    : Common linker script for STM32 devices.
**
*****************************************************************************
*/

/* Entry Point */
ENTRY(Reset_Handler)

/* Highest address of the user mode stack */
_estack = ORIGIN(STACKRAM) + LENGTH(STACKRAM);    /* end of RAM */

/* Base address where the config is stored. */
__config_start = ORIGIN(FLASH_CONFIG);
__config_end = ORIGIN(FLASH_CONFIG) + LENGTH(FLASH_CONFIG);

/* Generate a link error if heap and stack don't fit into RAM */
_Min_Heap_Size = 0;      /* required amount of heap  */
_Min_Stack_Size = 0x800; /* required amount of stack */

/* Define output sections */
SECTIONS
{
  /* The startup code goes first into FLASH */
  .isr_vector :
  {
    . = ALIGN(4);
    PROVIDE (isr_vector_table_base = .);
    KEEP(*(.isr_vector)) /* Startup code */
    . = ALIGN(4);
  } >FLASH

  /* The program code and other data goes into FLASH */
  .text :
  {
    . = ALIGN(4);
    *(.text)           /* .text sections (code) */
    *(.text*)          /* .text* sections (code) */
    *(.rodata)         /* .rodata sections (constants, strings, etc.) */
    *(.rodata*)        /* .rodata* sections (constants, strings, etc.) */
    *(.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

  /* Critical program code goes into CCM RAM */
  /* Copy specific fast-executing code to CCM RAM */ 
  ccm_code = LOADADDR(.ccm_code); 
  .ccm_code :
  {
    . = ALIGN(4);
    ccm_code_start = .; 
    *(.ccm_code)
    *(.ccm_code*)
    . = ALIGN(4);
    ccm_code_end = .; 
  } >CCM AT >FLASH


   .ARM.extab   : { *(.ARM.extab* .gnu.linkonce.armextab.*) } >FLASH
    .ARM : {
    __exidx_start = .;
      *(.ARM.exidx*)
      __exidx_end = .;
    } >FLASH

  .preinit_array     :
  {
    PROVIDE_HIDDEN (__preinit_array_start = .);
    KEEP (*(.preinit_array*))
    PROVIDE_HIDDEN (__preinit_array_end = .);
  } >FLASH
  .init_array :
  {
    PROVIDE_HIDDEN (__init_array_start = .);
    KEEP (*(SORT(.init_array.*)))
    KEEP (*(.init_array*))
    PROVIDE_HIDDEN (__init_array_end = .);
  } >FLASH
  .fini_array :
  {
    PROVIDE_HIDDEN (__fini_array_start = .);
    KEEP (*(.fini_array*))
    KEEP (*(SORT(.fini_array.*)))
    PROVIDE_HIDDEN (__fini_array_end = .);
  } >FLASH
  .pg_registry :
  {
    PROVIDE_HIDDEN (__pg_registry_start = .);
    KEEP (*(.pg_registry))
    KEEP (*(SORT(.pg_registry.*)))
    PROVIDE_HIDDEN (__pg_registry_end = .);
  } >FLASH
  .pg_resetdata :
  {
    PROVIDE_HIDDEN (__pg_resetdata_start = .);
    KEEP (*(.pg_resetdata))
    PROVIDE_HIDDEN (__pg_resetdata_end = .);
  } >FLASH

  /* used by the startup to initialize data */
  _sidata = .;

  /* Initialized data sections goes into RAM, load LMA copy after code */
  .data :
  {
    . = ALIGN(4);
    _sdata = .;        /* create a global symbol at data start */
    *(.data)           /* .data sections */
    *(.data*)          /* .data* sections */

    . = ALIGN(4);
    _edata = .;        /* define a global symbol at data end */
  } >RAM AT> FLASH

  /* Uninitialized data section */
  . = ALIGN(4);
  .bss :
  {
    /* This is used by the startup in order to initialize the .bss secion */
    _sbss = .;         /* define a global symbol at bss start */
    __bss_start__ = _sbss;
    *(.bss)
    *(SORT_BY_ALIGNMENT(.bss*))
    *(COMMON)

    . = ALIGN(4);
    _ebss = .;         /* define a global symbol at bss end */
    __bss_end__ = _ebss;
  } >RAM
  
  .fastram_bss (NOLOAD) :
  {
    __fastram_bss_start__ = .;
    *(.fastram_bss)
    *(SORT_BY_ALIGNMENT(.fastram_bss*))
    . = ALIGN(4);
    __fastram_bss_end__ = .;
  } >FASTRAM

  /* User_heap_stack section, used to check that there is enough RAM left */
  _heap_stack_end = ORIGIN(STACKRAM)+LENGTH(STACKRAM) - 8; /* 8 bytes to allow for alignment */
  _heap_stack_begin = _heap_stack_end - _Min_Stack_Size  - _Min_Heap_Size;
  . = _heap_stack_begin;
  ._user_heap_stack :
  {
    . = ALIGN(4);
    PROVIDE ( end = . );
    PROVIDE ( _end = . );
    . = . + _Min_Heap_Size;
    . = . + _Min_Stack_Size;
    . = ALIGN(4);
  } >STACKRAM = 0xa5

  /* MEMORY_bank1 section, code must be located here explicitly            */
  /* Example: extern int foo(void) __attribute__ ((section (".mb1text"))); */
  .memory_b1_text :
  {
    *(.mb1text)        /* .mb1text sections (code) */
    *(.mb1text*)       /* .mb1text* sections (code)  */
    *(.mb1rodata)      /* read-only data (constants) */
    *(.mb1rodata*)
  } >MEMORY_B1

  /* Remove information from the standard libraries */
  /DISCARD/ :
  {
    libc.a ( * )
    libm.a ( * )
    libgcc.a ( * )
  }

  .ARM.attributes 0 : { *(.ARM.attributes) }
}