From 31418ca8214145497c2b8c80552675b8232d68c1 Mon Sep 17 00:00:00 2001 From: Chloe Bethel Date: Thu, 16 Apr 2026 12:21:16 +0100 Subject: [PATCH] stm32wl: reserve 2KB of stack via linker script to match NRF52, change sbrkHeadroom to use the start of the reserved stack region instead of the current stack pointer The linker script was created by merging variants/STM32WLxx/WL54JCI_WL55JCI_WLE4J(8-B-C)I_WLE5J(8-B-C)I/ldscript.ld and system/ldscript.ld from stm32duino/Arduino_Core_STM32. --- src/memGet.cpp | 14 ++- variants/stm32/stm32.ini | 3 + variants/stm32/stm32wle5xx.ld | 204 ++++++++++++++++++++++++++++++++++ 3 files changed, 217 insertions(+), 4 deletions(-) create mode 100644 variants/stm32/stm32wle5xx.ld diff --git a/src/memGet.cpp b/src/memGet.cpp index 570bbf5b2..42a3430f6 100644 --- a/src/memGet.cpp +++ b/src/memGet.cpp @@ -14,16 +14,22 @@ #include #include // sbrk +#ifdef ARCH_STM32WL // Returns the uncommitted sbrk headroom: addressable space between the current heap // break and the stack pointer that has not yet been committed to the arena. -// Currently used on: ARCH_STM32WL static uint32_t sbrkHeadroom() { - uint32_t sp; - __asm volatile("mov %0, sp" : "=r"(sp)); + // defined in STM32 linker script + extern char _estack; + extern char _Min_Stack_Size; + + uint32_t max_sp = (uint32_t)(&_estack - &_Min_Stack_Size); uint32_t heap_end = (uint32_t)sbrk(0); - return (sp > heap_end) ? (sp - heap_end) : 0; + return (max_sp > heap_end) ? (max_sp - heap_end) : 0; } +#else +#error Unsupported architecture! +#endif #endif MemGet memGet; diff --git a/variants/stm32/stm32.ini b/variants/stm32/stm32.ini index c49db27f3..1efe18e3d 100644 --- a/variants/stm32/stm32.ini +++ b/variants/stm32/stm32.ini @@ -58,3 +58,6 @@ lib_deps = lib_ignore = OneButton + +; Set a custom linker script with a higher MinStackSize value, to match NRF52. +board_build.ldscript = $PROJECT_DIR/variants/stm32/stm32wle5xx.ld \ No newline at end of file diff --git a/variants/stm32/stm32wle5xx.ld b/variants/stm32/stm32wle5xx.ld new file mode 100644 index 000000000..c13782926 --- /dev/null +++ b/variants/stm32/stm32wle5xx.ld @@ -0,0 +1,204 @@ +/* +****************************************************************************** +** +** File : LinkerScript.ld +** +** Author : STM32CubeIDE +** +** Abstract : Linker script for STM32WL55xC Device +** 256Kbytes FLASH +** 64Kbytes 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) 2020 STMicroelectronics. +** All rights reserved.

+** +** This software component is licensed by ST under BSD 3-Clause license, +** the "License"; You may not use this file except in compliance with the +** License. You may obtain a copy of the License at: +** opensource.org/licenses/BSD-3-Clause +** +***************************************************************************** +*/ + +/* 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 */ +/* Modified from original to 2KB, to match NRF52 */ +_Min_Stack_Size = 2048 ; /* required amount of stack */ + +/* Memories definition */ +MEMORY +{ + RAM (xrw) : ORIGIN = 0x20000000, LENGTH = LD_MAX_DATA_SIZE + FLASH (rx) : ORIGIN = 0x08000000 + LD_FLASH_OFFSET, LENGTH = LD_MAX_SIZE - LD_FLASH_OFFSET +} + +/* Sections */ +SECTIONS +{ + /* The startup code into "FLASH" Rom type memory */ + .isr_vector : + { + . = ALIGN(4); + KEEP(*(.isr_vector)) /* Startup code */ + . = ALIGN(4); + } >FLASH + + /* 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 (READONLY) : { + . = ALIGN(4); + *(.ARM.extab* .gnu.linkonce.armextab.*) + . = ALIGN(4); + } >FLASH + + .ARM (READONLY) : { + . = ALIGN(4); + __exidx_start = .; + *(.ARM.exidx*) + __exidx_end = .; + . = ALIGN(4); + } >FLASH + + .preinit_array (READONLY) : + { + . = ALIGN(4); + PROVIDE_HIDDEN (__preinit_array_start = .); + KEEP (*(.preinit_array*)) + PROVIDE_HIDDEN (__preinit_array_end = .); + . = ALIGN(4); + } >FLASH + + .init_array (READONLY) : + { + . = ALIGN(4); + PROVIDE_HIDDEN (__init_array_start = .); + KEEP (*(SORT(.init_array.*))) + KEEP (*(.init_array*)) + PROVIDE_HIDDEN (__init_array_end = .); + . = ALIGN(4); + } >FLASH + + .fini_array (READONLY) : + { + . = 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 + + /* Define a noinit output section and mark it as NOLOAD to prevent + * putting its contents into the resulting .bin file (which is the + * default). */ + .noinit (NOLOAD) : + { + /* Ensure output is aligned */ + . = ALIGN(4); + /* Define a global _snoinit (and _enoinit below) symbol just in case + * code wants to iterate over all noinit variables for some reason */ + _snoinit = .; + /* Actually import the .noinit and .noinit* import sections */ + *(.noinit) + *(.noinit*) + . = ALIGN(4); + _enoinit = .; + } >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) } +}