我在将代码重新映射到envm上的其他位置时遇到一些问题，
在干净复位后运行启动代码（启动代码放置在envm的开头（0x60000000））下，一切正常，这是启动代码的链接文件，并且启动代码跳至主应用程序代码（主应用代码放置在0x60020000）在某些情况下
/*******************************************************************************
* (c) Copyright 2015 Microsemi SoC Products Group. All rights reserved.
*
* file name : production-smartfusion2-execute-in-place.ld
* SmartFusion2 Cortex-M3 linker script for creating a SoftConsole downloadable
* image executing in SmartFusion2 internal eNVM.
*
* Some current (April 2015) dev kit memory map possibilities are
* --Type-------Device-----------address start---address end----size---Dbus--RAM IC-------SF2--Comment---------------
* --eNVM-------M2S010-----------0x60000000------0x6007FFFF-----256KB---------------------010------------------------
* --eNVM-------M2S090-----------0x60000000------0x6007FFFF-----512KB---------------------090------------------------
* --eSRAM------M2Sxxx-----------0x20000000------0x2000FFFF-----64KB----------------------xxx--All have same amount--
* --eSRAM------M2Sxxx-----------0x20000000------0x20013FFF-----80KB----------------------xxx--If ECC/SECDED not used
* --Fabric-----M2S010-----------0x30000000------0x6007FFFF-----400Kb---------------------010--note-K bits-----------
* --Fabric-----M2S090-----------0x30000000------0x6007FFFF-----2074Kb--------------------090--note-K bits-----------
* --LPDDR------STARTER-KIT------0xA0000000------0xA3FFFFFF-----64MB---16--MT46H32M16-----050------------------------
* --LPDDR------484-STARTER-KIT--0xA0000000------0xA3FFFFFF-----64MB---16--MT46H32M16-----010------------------------
* --LPDDR------SEC-EVAL-KIT-----0xA0000000------0xA3FFFFFF-----64MB---16--MT46H32M16LF---090--Security eval kit-----
* --DDR3-------ADevKit----------0xA0000000------0xBFFFFFFF-----1GB----32--MT41K256M8DA---150------------------------
* --Some older physical memory map possibilities are
* --Type-------location---------address start---address end----size---Dbus---RAM IC------SF2--Comment--------------
* --LPDDR------EVAL KIT---------0xA0000000------0xA3FFFFFF-----64MB-=-16--MT46H32M16LF---025--Eval Kit--------------
* --DDR3-------DevKit-----------0xA0000000------0xAFFFFFFF-----512MB--16--MT41K256M8DA---050------------------------
*
* Example linker scripts use lowest practicl values so will work accross dev kits
* eNVM=256KB eRAM=64KB External memory = 64MB
*
* On reset, the eNVM region is mapped to 0x00000000
* This is changed below by setting the __smartfusion2_memory_remap variable as required.
* Options are detailed below.
*
* SVN $Revision: 7683 $
* SVN $Date: 2015-08-21 17:06:30 +0100 (Fri, 21 Aug 2015) $
*/
OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
GROUP(-lc -lgcc -lm)
OUTPUT_ARCH(arm)
ENTRY(Reset_Handler)
SEARCH_DIR(.)
__DYNAMIC = 0;
/*******************************************************************************
* Start of board customization.
*******************************************************************************/
MEMORY
{
/*
* In general, example LD scripts use lowest common memory footprint
* so will work with all devices.
*/
/*
* WARNING: The words "SOFTCONSOLE", "FLASH", and "USE", the colon ":", and
* the name of the type of flash memory are all in a specific order.
* Please do not modify that comment line, in order to ensure
* debugging of your application will use the flash memory correctly.
*/
/* SOFTCONSOLE FLASH USE: microsemi-smartfusion2-envm */
rom (rx) : ORIGIN = 0x00000000, LENGTH = 8k
/* SmartFusion2 internal eSRAM */
ram (rwx) : ORIGIN = 0x2000F000, LENGTH = 4k
}
RAM_START_ADDRESS = 0x2000F000; /* Must be the same value MEMORY region ram ORIGIN above. */
RAM_SIZE = 4k; /* Must be the same value MEMORY region ram LENGTH above. */
MAIN_STACK_SIZE = 2k; /* Cortex main stack size. */
MIN_SIZE_HEAP = 0k; /* needs to be calculated for your application */
/*******************************************************************************
* End of board customization.
*******************************************************************************/
PROVIDE (__main_stack_start = RAM_START_ADDRESS + RAM_SIZE);
PROVIDE (__process_stack_start = __main_stack_start - MAIN_STACK_SIZE);
PROVIDE (_estack = __main_stack_start);
PROVIDE (__mirrored_nvm = 0); /* Indicate to startup code that NVM is not mirrored to VMA address .text copy is required. */
/*
* Remap instruction for startup code and debugger:
* 0: remap eNVM to address 0x00000000
* 1: remap eSRAM to address 0x00000000
* 2: remap external DDR memory to address 0x00000000
*/
PROVIDE (__smartfusion2_memory_remap = 0);
SECTIONS
{
.vector_table :
{
__vector_table_load = LOADADDR(.vector_table);
__vector_table_start = .;
__vector_table_vma_base_address = .;
KEEP(*(.isr_vector))
. = ALIGN(0x10);
_evector_table = .;
} >rom
.boot_code : ALIGN(0x10) /* When all code in NVRAM, no requirement for this section- but adds clarity when looking at .lst file */
{
*(.boot_code)
. = ALIGN(0x10);
} >rom
.text : ALIGN(0x10)
{
CREATE_OBJECT_SYMBOLS
__text_load = LOADADDR(.text);
__text_start = .;
*(.text .text.* .gnu.linkonce.t.*)
*(.plt)
*(.gnu.warning)
*(.glue_7t) *(.glue_7) *(.vfp11_veneer)
. = ALIGN(0x4);
/* These are for running static constructors and destructors under ELF. */
KEEP (*crtbegin.o(.ctors))
KEEP (*(EXCLUDE_FILE (*crtend.o) .ctors))
KEEP (*(SORT(.ctors.*)))
KEEP (*crtend.o(.ctors))
KEEP (*crtbegin.o(.dtors))
KEEP (*(EXCLUDE_FILE (*crtend.o) .dtors))
KEEP (*(SORT(.dtors.*)))
KEEP (*crtend.o(.dtors))
*(.rodata .rodata.* .gnu.linkonce.r.*)
*(.ARM.extab* .gnu.linkonce.armextab.*)
*(.gcc_except_table)
*(.eh_frame_hdr)
*(.eh_frame)
KEEP (*(.vector_table))
KEEP (*(.init))
KEEP (*(.fini))
PROVIDE_HIDDEN (__preinit_array_start = .);
KEEP (*(.preinit_array))
PROVIDE_HIDDEN (__preinit_array_end = .);
PROVIDE_HIDDEN (__init_array_start = .);
KEEP (*(SORT(.init_array.*)))
KEEP (*(.init_array))
PROVIDE_HIDDEN (__init_array_end = .);
PROVIDE_HIDDEN (__fini_array_start = .);
KEEP (*(.fini_array))
KEEP (*(SORT(.fini_array.*)))
PROVIDE_HIDDEN (__fini_array_end = .);
. = ALIGN(0x10);
} >rom
/* .ARM.exidx is sorted, so has to go in its own output section. */
__exidx_start = .;
.ARM.exidx :
{
*(.ARM.exidx* .gnu.linkonce.armexidx.*)
} >rom
__exidx_end = .;
_etext = .;
.data : ALIGN(0x10)
{
__data_load = LOADADDR(.data);
_sidata = LOADADDR (.data);
__data_start = .;
_sdata = .;
KEEP(*(.jcr))
*(.got.plt) *(.got)
*(.shdata)
*(.data .data.* .gnu.linkonce.d.*)
. = ALIGN(0x10);
_edata = .;
} >ram AT>rom
.bss : ALIGN(0x10)
{
__bss_start__ = . ;
_sbss = .;
*(.shbss)
*(.bss .bss.* .gnu.linkonce.b.*)
*(COMMON)
. = ALIGN(0x10);
__bss_end__ = .;
_end = .;
__end = _end;
_ebss = .;
PROVIDE(end = .);
} >ram AT>rom
.heap : ALIGN(0x10)
{
__heap_start__ = .;
. += MIN_SIZE_HEAP; /* will generate error if this minimum size not available */
. += ((ABSOLUTE(RAM_START_ADDRESS) + RAM_SIZE - MAIN_STACK_SIZE) - .); /* assumes stack starts after heap */
_eheap = .;
} >ram
.stack : ALIGN(0x10)
{
__stack_start__ = .;
. += MAIN_STACK_SIZE;
_estack = .;
} >ram
.stab 0 (NOLOAD) :
{
*(.stab)
}
.stabstr 0 (NOLOAD) :
{
*(.stabstr)
}
/* DWARF debug sections.
Symbols in the DWARF debugging sections are relative to the beginning
of the section so we begin them at 0. */
/* DWARF 1 */
.debug 0 : { *(.debug) }
.line 0 : { *(.line) }
/* GNU DWARF 1 extensions */
.debug_srcinfo 0 : { *(.debug_srcinfo) }
.debug_sfnames 0 : { *(.debug_sfnames) }
/* DWARF 1.1 and DWARF 2 */
.debug_aranges 0 : { *(.debug_aranges) }
.debug_pubnames 0 : { *(.debug_pubnames) }
/* DWARF 2 */
.debug_info 0 : { *(.debug_info .gnu.linkonce.wi.*) }
.debug_abbrev 0 : { *(.debug_abbrev) }
.debug_line 0 : { *(.debug_line) }
.debug_frame 0 : { *(.debug_frame) }
.debug_str 0 : { *(.debug_str) }
.debug_loc 0 : { *(.debug_loc) }
.debug_macinfo 0 : { *(.debug_macinfo) }
/* SGI/MIPS DWARF 2 extensions */
.debug_weaknames 0 : { *(.debug_weaknames) }
.debug_funcnames 0 : { *(.debug_funcnames) }
.debug_typenames 0 : { *(.debug_typenames) }
.debug_varnames 0 : { *(.debug_varnames) }
.note.gnu.arm.ident 0 : { KEEP (*(.note.gnu.arm.ident)) }
.ARM.attributes 0 : { KEEP (*(.ARM.attributes)) }
/DISCARD/ : { *(.note.GNU-stack) }
}
跳转代码为
int * address = (int *)0x60020004; //pointer to reset handler of application
__set_MSP(*(int*)0x60020000); //set the stack pointer to that of the application
SYSREG->ENVM_CR &= 0b11111111111111111111111111100000;
SYSREG->ENVM_CR |= 0b10000;
SYSREG->ENVM_REMAP_BASE_CR = 0x20001;
((void (*)())(*address))(); // pointer recast as function pointer and the dereferenced/called
while(1)
{
}; //This instruction never executed
此代码运行正常，但是在必要的事情发生时我想返回引导代码。因此，请编写此代码以进行恢复，但是当此代码开始执行时，主代码会出现严重错误，
void remap_user_code_eNVM_to_zero(void)
{
__disable_irq();
msdelay(3000);
__asm ("ldr r1,=0x60000000");
__asm ("ldr r0,[r1]");
__asm("msr msp,r0");
SYSREG->ENVM_CR &= 0b11111111111111111111111111100000;
SYSREG->ENVM_CR |= 0b01111;
SYSREG->ENVM_REMAP_BASE_CR = 0x00001;
SYSREG->ENVM_CR &= 0b11111111111111111111111111100000;
SYSREG->ENVM_CR |= 0b10000;
SYSREG->ENVM_REMAP_BASE_CR = 0x0000;
__asm ("ldr r1,=0x60000004");
__asm ("ldr r0,[r1]");
__asm ("add r0,r0,#4");
__asm ("bx r0");
while(1)
{
}; //This instruction never executed
}
我只需使用一行命令“ *（uint32_t *）0xe000ed0c = 0x05fa0004”就可以解决此问题，但是我想正确地学习这种机制
主应用程序代码的链接器文件为
/*******************************************************************************
* (c) Copyright 2015 Microsemi SoC Products Group. All rights reserved.
*
* file name : production-smartfusion2-execute-in-place.ld
* SmartFusion2 Cortex-M3 linker script for creating a SoftConsole downloadable
* image executing in SmartFusion2 internal eNVM.
*
* Some current (April 2015) dev kit memory map possibilities are
* --Type-------Device-----------address start---address end----size---Dbus--RAM IC-------SF2--Comment---------------
* --eNVM-------M2S010-----------0x60000000------0x6007FFFF-----256KB---------------------010------------------------
* --eNVM-------M2S090-----------0x60000000------0x6007FFFF-----512KB---------------------090------------------------
* --eSRAM------M2Sxxx-----------0x20000000------0x2000FFFF-----64KB----------------------xxx--All have same amount--
* --eSRAM------M2Sxxx-----------0x20000000------0x20013FFF-----80KB----------------------xxx--If ECC/SECDED not used
* --Fabric-----M2S010-----------0x30000000------0x6007FFFF-----400Kb---------------------010--note-K bits-----------
* --Fabric-----M2S090-----------0x30000000------0x6007FFFF-----2074Kb--------------------090--note-K bits-----------
* --LPDDR------STARTER-KIT------0xA0000000------0xA3FFFFFF-----64MB---16--MT46H32M16-----050------------------------
* --LPDDR------484-STARTER-KIT--0xA0000000------0xA3FFFFFF-----64MB---16--MT46H32M16-----010------------------------
* --LPDDR------SEC-EVAL-KIT-----0xA0000000------0xA3FFFFFF-----64MB---16--MT46H32M16LF---090--Security eval kit-----
* --DDR3-------ADevKit----------0xA0000000------0xBFFFFFFF-----1GB----32--MT41K256M8DA---150------------------------
* --Some older physical memory map possibilities are
* --Type-------location---------address start---address end----size---Dbus---RAM IC------SF2--Comment--------------
* --LPDDR------EVAL KIT---------0xA0000000------0xA3FFFFFF-----64MB-=-16--MT46H32M16LF---025--Eval Kit--------------
* --DDR3-------DevKit-----------0xA0000000------0xAFFFFFFF-----512MB--16--MT41K256M8DA---050------------------------
*
* Example linker scripts use lowest practicl values so will work accross dev kits
* eNVM=256KB eRAM=64KB External memory = 64MB
*
* On reset, the eNVM region is mapped to 0x00000000
* This is changed below by setting the __smartfusion2_memory_remap variable as required.
* Options are detailed below.
*
* SVN $Revision: 7683 $
* SVN $Date: 2015-08-21 17:06:30 +0100 (Fri, 21 Aug 2015) $
*/
OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
GROUP(-lc -lgcc -lm)
OUTPUT_ARCH(arm)
ENTRY(Reset_Handler)
SEARCH_DIR(.)
__DYNAMIC = 0;
/*******************************************************************************
* Start of board customization.
*******************************************************************************/
MEMORY
{
/*
* In general, example LD scripts use lowest common memory footprint
* so will work with all devices.
*/
/*
* WARNING: The words "SOFTCONSOLE", "FLASH", and "USE", the colon ":", and
* the name of the type of flash memory are all in a specific order.
* Please do not modify that comment line, in order to ensure
* debugging of your application will use the flash memory correctly.
*/
/* SOFTCONSOLE FLASH USE: microsemi-smartfusion2-envm */
rom (rx) : ORIGIN = 0x00000000, LENGTH = 128k
/* SmartFusion2 internal eSRAM */
ram (rwx) : ORIGIN = 0x20000000, LENGTH = 60k
}
RAM_START_ADDRESS = 0x20000000; /* Must be the same value MEMORY region ram ORIGIN above. */
RAM_SIZE = 60k; /* Must be the same value MEMORY region ram LENGTH above. */
MAIN_STACK_SIZE = 4k; /* Cortex main stack size. */
MIN_SIZE_HEAP = 4k; /* needs to be calculated for your application */
/*******************************************************************************
* End of board customization.
*******************************************************************************/
PROVIDE (__main_stack_start = RAM_START_ADDRESS + RAM_SIZE);
PROVIDE (__process_stack_start = __main_stack_start - MAIN_STACK_SIZE);
PROVIDE (_estack = __main_stack_start);
PROVIDE (__mirrored_nvm = 0); /* Indicate to startup code that NVM is not mirrored to VMA address .text copy is required. */
/*
* Remap instruction for startup code and debugger:
* 0: remap eNVM to address 0x00000000
* 1: remap eSRAM to address 0x00000000
* 2: remap external DDR memory to address 0x00000000
*/
PROVIDE (__smartfusion2_memory_remap = 0);
SECTIONS
{
.vector_table :
{
__vector_table_load = LOADADDR(.vector_table);
__vector_table_start = .;
__vector_table_vma_base_address = .;
KEEP(*(.isr_vector))
. = ALIGN(0x10);
_evector_table = .;
} >rom
.boot_code : ALIGN(0x10) /* When all code in NVRAM, no requirement for this section- but adds clarity when looking at .lst file */
{
*(.boot_code)
. = ALIGN(0x10);
} >rom
.text : ALIGN(0x10)
{
CREATE_OBJECT_SYMBOLS
__text_load = LOADADDR(.text);
__text_start = .;
*(.text .text.* .gnu.linkonce.t.*)
*(.plt)
*(.gnu.warning)
*(.glue_7t) *(.glue_7) *(.vfp11_veneer)
. = ALIGN(0x4);
/* These are for running static constructors and destructors under ELF. */
KEEP (*crtbegin.o(.ctors))
KEEP (*(EXCLUDE_FILE (*crtend.o) .ctors))
KEEP (*(SORT(.ctors.*)))
KEEP (*crtend.o(.ctors))
KEEP (*crtbegin.o(.dtors))
KEEP (*(EXCLUDE_FILE (*crtend.o) .dtors))
KEEP (*(SORT(.dtors.*)))
KEEP (*crtend.o(.dtors))
*(.rodata .rodata.* .gnu.linkonce.r.*)
*(.ARM.extab* .gnu.linkonce.armextab.*)
*(.gcc_except_table)
*(.eh_frame_hdr)
*(.eh_frame)
KEEP (*(.vector_table))
KEEP (*(.init))
KEEP (*(.fini))
PROVIDE_HIDDEN (__preinit_array_start = .);
KEEP (*(.preinit_array))
PROVIDE_HIDDEN (__preinit_array_end = .);
PROVIDE_HIDDEN (__init_array_start = .);
KEEP (*(SORT(.init_array.*)))
KEEP (*(.init_array))
PROVIDE_HIDDEN (__init_array_end = .);
PROVIDE_HIDDEN (__fini_array_start = .);
KEEP (*(.fini_array))
KEEP (*(SORT(.fini_array.*)))
PROVIDE_HIDDEN (__fini_array_end = .);
. = ALIGN(0x10);
} >rom
/* .ARM.exidx is sorted, so has to go in its own output section. */
__exidx_start = .;
.ARM.exidx :
{
*(.ARM.exidx* .gnu.linkonce.armexidx.*)
} >rom
__exidx_end = .;
_etext = .;
.data : ALIGN(0x10)
{
__data_load = LOADADDR(.data);
_sidata = LOADADDR (.data);
__data_start = .;
_sdata = .;
KEEP(*(.jcr))
*(.got.plt) *(.got)
*(.shdata)
*(.data .data.* .gnu.linkonce.d.*)
. = ALIGN(0x10);
_edata = .;
} >ram AT>rom
.bss : ALIGN(0x10)
{
__bss_start__ = . ;
_sbss = .;
*(.shbss)
*(.bss .bss.* .gnu.linkonce.b.*)
*(COMMON)
. = ALIGN(0x10);
__bss_end__ = .;
_end = .;
__end = _end;
_ebss = .;
PROVIDE(end = .);
} >ram AT>rom
.heap : ALIGN(0x10)
{
__heap_start__ = .;
. += MIN_SIZE_HEAP; /* will generate error if this minimum size not available */
. += ((ABSOLUTE(RAM_START_ADDRESS) + RAM_SIZE - MAIN_STACK_SIZE) - .); /* assumes stack starts after heap */
_eheap = .;
} >ram
.stack : ALIGN(0x10)
{
__stack_start__ = .;
. += MAIN_STACK_SIZE;
_estack = .;
} >ram
.stab 0 (NOLOAD) :
{
*(.stab)
}
.stabstr 0 (NOLOAD) :
{
*(.stabstr)
}
/* DWARF debug sections.
Symbols in the DWARF debugging sections are relative to the beginning
of the section so we begin them at 0. */
/* DWARF 1 */
.debug 0 : { *(.debug) }
.line 0 : { *(.line) }
/* GNU DWARF 1 extensions */
.debug_srcinfo 0 : { *(.debug_srcinfo) }
.debug_sfnames 0 : { *(.debug_sfnames) }
/* DWARF 1.1 and DWARF 2 */
.debug_aranges 0 : { *(.debug_aranges) }
.debug_pubnames 0 : { *(.debug_pubnames) }
/* DWARF 2 */
.debug_info 0 : { *(.debug_info .gnu.linkonce.wi.*) }
.debug_abbrev 0 : { *(.debug_abbrev) }
.debug_line 0 : { *(.debug_line) }
.debug_frame 0 : { *(.debug_frame) }
.debug_str 0 : { *(.debug_str) }
.debug_loc 0 : { *(.debug_loc) }
.debug_macinfo 0 : { *(.debug_macinfo) }
/* SGI/MIPS DWARF 2 extensions */
.debug_weaknames 0 : { *(.debug_weaknames) }
.debug_funcnames 0 : { *(.debug_funcnames) }
.debug_typenames 0 : { *(.debug_typenames) }
.debug_varnames 0 : { *(.debug_varnames) }
.note.gnu.arm.ident 0 : { KEEP (*(.note.gnu.arm.ident)) }
.ARM.attributes 0 : { KEEP (*(.ARM.attributes)) }
/DISCARD/ : { *(.note.GNU-stack) }
}