我想从闪存地址运行我的固件：0x08040000
所以我对软件的内存布局进行了分区，如下所示：
ENTRY(Reset_Handler)
/* Highest address of the user mode stack */
_estack = 0x20080000; /* end of RAM */
/* Generate a link error if heap and stack don't fit into RAM */
_Min_Heap_Size = 0x1000; /* required amount of heap */
_Min_Stack_Size = 0x2000; /* required amount of stack */
/* Specify the memory areas */
MEMORY
{
FLASH (rx) : ORIGIN = 0x08040000, LENGTH = 768K
FLASH2 (r) : ORIGIN = 0x08100000, LENGTH = 1024K
SRAM1 (xrw) : ORIGIN = 0x20020000, LENGTH = 368K
SRAM2 (xrw) : ORIGIN = 0x2007C000, LENGTH = 16K
DTCMRAM (wal) : ORIGIN = 0x20000000, LENGTH = 128K
MEMORY_B1 (rx) : ORIGIN = 0x60000000, LENGTH = 0K
}
main_stack_base = _estack;
/* used by the startup code to populate variables used by the C code */
data_lma = LOADADDR(.data);
data_vma = ADDR(.data);
data_size = SIZEOF(.data);
/* used by the startup code to wipe memory */
ccmram_start = ORIGIN(SRAM1);
ccmram_end = ORIGIN(SRAM1) + 4;
/* used by the startup code to wipe memory */
sram_start = ORIGIN(SRAM1);
sram_end = ORIGIN(SRAM1) + LENGTH(SRAM1);
_ram_start = sram_start;
_ram_end = sram_end;
_codelen = LENGTH(FLASH);
_flash_start = ORIGIN(FLASH);
_flash_end = ORIGIN(FLASH) + LENGTH(FLASH);
_heap_start = ADDR(.heap);
_heap_end = ADDR(.heap) + SIZEOF(.heap);
/* Define output sections */
SECTIONS
{
/* The startup code goes first into FLASH */
.isr_vector :
{
. = ALIGN(4);
KEEP(*(.isr_vector)) /* Startup code */
. = ALIGN(4);
} >FLASH
.flash2 : ALIGN(512) {
build/firmware_rnc/frozen_mpy.o(.rodata*);
build/firmware_rnc/vendor/secp256k1-zkp/src/secp256k1.o(.rodata*);
. = ALIGN(512);
} >FLASH2 AT>FLASH2
/* The program code and other data goes into FLASH */
.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 goes into FLASH */
.rodata :
{
. = ALIGN(4);
*(.rodata) /* .rodata sections (constants, strings, etc.) */
*(.rodata*) /* .rodata* sections (constants, strings, etc.) */
. = ALIGN(4);
} >FLASH2 AT>FLASH2
.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 (*(SORT(.fini_array.*)))
KEEP (*(.fini_array*))
PROVIDE_HIDDEN (__fini_array_end = .);
} >FLASH
/* used by the startup to initialize data */
_sidata = LOADADDR(.data);
/* 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 */
} >SRAM1 AT> FLASH
_sidtcmram = LOADADDR(.dtcmram);
/* DTCMRAM section
*
* IMPORTANT NOTE!
* If initialized variables will be placed in this section,
* the startup code needs to be modified to copy the init-values.
*/
.dtcmram :
{
. = ALIGN(4);
_sdtcmram = .; /* create a global symbol at dtcmram start */
*(.dtcmram)
*(.dtcmram*)
. = ALIGN(4);
_edtcmram = .; /* create a global symbol at dtcmram end */
} >DTCMRAM AT> FLASH
_sisram2 = LOADADDR(.sram2);
/* SRAM2 section
*
* IMPORTANT NOTE!
* If initialized variables will be placed in this section,
* the startup code needs to be modified to copy the init-values.
*/
.sram2 :
{
. = ALIGN(4);
_ssram2 = .; /* create a global symbol at sram2 start */
*(.sram2)
*(.sram2*)
. = ALIGN(4);
_esram2 = .; /* create a global symbol at sram2 end */
} >SRAM2 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)
*(.bss*)
*(COMMON)
. = ALIGN(4);
_ebss = .; /* define a global symbol at bss end */
__bss_end__ = _ebss;
} >SRAM1
.heap : ALIGN(4) {
. = 37K; /* this acts as a build time assertion that at least this much memory is available for heap use */
. = ABSOLUTE(sram_end - 16K); /* this explicitly sets the end of the heap effectively giving the stack at most 16K */
} >SRAM1
.stack : ALIGN(8) {
. = 4K; /* this acts as a build time assertion that at least this much memory is available for stack use */
} >SRAM1
/* 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) }
}
我的创业公司看起来像这样：
.syntax unified
.cpu cortex-m7
.fpu softvfp
.thumb
.global g_pfnVectors
.global Default_Handler
/* start address for the initialization values of the .data section.
defined in linker script */
.word _sidata
/* start address for the .data section. defined in linker script */
.word _sdata
/* end address for the .data section. defined in linker script */
.word _edata
/* start address for the .bss section. defined in linker script */
.word _sbss
/* end address for the .bss section. defined in linker script */
.word _ebss
/* stack used for SystemInit_ExtMemCtl; always internal RAM used */
/**
* @brief This is the code that gets called when the processor first
* starts execution following a reset event. Only the absolutely
* necessary set is performed, after which the application
* supplied main() routine is called.
* @param None
* @retval : None
*/
.section .text.Reset_Handler
.weak Reset_Handler
.type Reset_Handler, %function
Reset_Handler:
ldr sp, =_estack /* set stack pointer */
/* Copy the data segment initializers from flash to SRAM */
movs r1, #0
b LoopCopyDataInit
CopyDataInit:
ldr r3, =_sidata
ldr r3, [r3, r1]
str r3, [r0, r1]
adds r1, r1, #4
LoopCopyDataInit:
ldr r0, =_sdata
ldr r3, =_edata
adds r2, r0, r1
cmp r2, r3
bcc CopyDataInit
ldr r2, =_sbss
b LoopFillZerobss
/* Zero fill the bss segment. */
FillZerobss:
movs r3, #0
str r3, [r2], #4
LoopFillZerobss:
ldr r3, = _ebss
cmp r2, r3
bcc FillZerobss
/* Call the clock system intitialization function.*/
bl SystemInit
/* Call static constructors */
/* Call the application's entry point.*/
bl main
bx lr
.size Reset_Handler, .-Reset_Handler
问题是：固件没有进入主功能，它总是在其中一个.c文件中跳转到某个地方。 问题出在哪里？
复位向量的地址由
- 复位时 BOOT 引脚上的逻辑电平
- 用户选项字节中的 nDBANK 和 nDBOOT 位的内容
- 引导地址选项字节的内容
根据参考手册的第 2.5 章和第 3.4 章，验证所有这些是否包含正确的值。
如果它们仍然具有默认值，并且 BOOT 引脚被拉低，则 CPU 将使用清除位 0 的 0x08000004 处的值作为起始地址，并使用 0x08000000 处的值作为初始堆栈指针。您可以将图像开头的前 8 个字节复制到闪存中的0x08000000，也可以在选项字节中设置备用地址。