boot使用的是这个例子， https://whycan.com/t_3645.html
于是想在这个boot上改个IAP，我修改了start.S,如下
/*
* Exception vector table
*/
.text
.arm
.global _start
_start:
/* Boot head information for BROM */
//.long 0xea000016
//.byte 'e', 'G', 'O', 'N', '.', 'B', 'T', '0'
//.long 0, __bootloader_size
//.byte 'S', 'P', 'L', 2
//.long 0, 0
//.long 0, 0, 0, 0, 0, 0, 0, 0
//.long 0, 0, 0, 0, 0, 0, 0, 0 /* 0x40 - boot params, 0x58 - fel boot type, 0x5c - dram size */
_vector:
b reset
ldr pc, _undefined_instruction
ldr pc, _software_interrupt
ldr pc, _prefetch_abort
ldr pc, _data_abort
ldr pc, _not_used
ldr pc, _irq
ldr pc, _fiq
_undefined_instruction:
.word undefined_instruction
_software_interrupt:
.word software_interrupt
_prefetch_abort:
.word prefetch_abort
_data_abort:
.word data_abort
_not_used:
.word not_used
_irq:
.word irq
_fiq:
.word fiq
/*
* The actual reset code
*/
reset:
/* Save boot params to 0x00000040 */
//ldr r0, =0x00000040
//str sp, [r0, #0]
//str lr, [r0, #4]
//mrs lr, cpsr
//str lr, [r0, #8]
//mrc p15, 0, lr, c1, c0, 0
//str lr, [r0, #12]
//mrc p15, 0, lr, c1, c0, 0
//str lr, [r0, #16]
/* Check boot type just for fel */
// mov r0, #0x0
// ldr r1, [r0, #8]
// ldr r2, =0x4c45462e
// cmp r1, r2
// bne 1f
// ldr r1, =0x1
// str r1, [r0, #0x58]
//1: nop
/* Enter svc mode and mask interrupts */
// mrs r0, cpsr
// bic r0, r0, #0x1f
// orr r0, r0, #0xd3
// msr cpsr, r0
/* Set vector to the low address */
mrc p15, 0, r0, c1, c0, 0
bic r0, #(1<<13)
mcr p15, 0, r0, c1, c0, 0
/* Copy vector to the correct address */
adr r0, _vector
mrc p15, 0, r2, c1, c0, 0
ands r2, r2, #(1 << 13)
ldreq r1, =0x00000000
ldrne r1, =0xffff0000
ldmia r0!, {r2-r8, r10}
stmia r1!, {r2-r8, r10}
ldmia r0!, {r2-r8, r10}
stmia r1!, {r2-r8, r10}
/* Initial system clock, ddr add uart */
// bl sys_clock_init
// bl sys_dram_init
// bl sys_uart_init
/* Boot speed up, leave slower sram */
// adr r0, _start
// ldr r1, =_start
// cmp r0, r1
// beq _speedup
// ldr r0, =0x81f80000
// adr r1, _start
// mov r2, #0x4000
// bl memcpy
// ldr r0, =_speedup
// ldr r1, =_start
// sub r0, r0, r1
// ldr r1, =0x81f80000
// add r0, r0, r1
// mov pc, r0
//_speedup:
// nop
/* Copyself to link address */
// adr r0, _start
// ldr r1, =_start
// cmp r0, r1
// beq 1f
// bl sys_copyself
//1: nop
/* Initialize stacks */
mrs r0, cpsr
bic r0, r0, #0x1f
orr r1, r0, #0x1b
msr cpsr_cxsf, r1
ldr sp, _stack_und_end
bic r0, r0, #0x1f
orr r1, r0, #0x17
msr cpsr_cxsf, r1
ldr sp, _stack_abt_end
bic r0, r0, #0x1f
orr r1, r0, #0x12
msr cpsr_cxsf, r1
ldr sp, _stack_irq_end
bic r0, r0, #0x1f
orr r1, r0, #0x11
msr cpsr_cxsf, r1
ldr sp, _stack_fiq_end
bic r0, r0, #0x1f
orr r1, r0, #0x1f
msr cpsr_cxsf, r1
ldr sp, _stack_usr_end
bic r0, r0, #0x1f
orr r1, r0, #0x13
msr cpsr_cxsf, r1
ldr sp, _stack_srv_end
/* Copy data section */
ldr r0, _data_start
ldr r1, _data_shadow_start
ldr r2, _data_shadow_end
sub r2, r2, r1
bl memcpy
/* Clear bss section */
ldr r0, _bss_start
ldr r2, _bss_end
sub r2, r2, r0
mov r1, #0
bl memset
/* Call _main */
ldr r1, =_main
mov pc, r1
_main:
mov r0, #1;
mov r1, #0;
bl boot_main
b _main
// .global return_to_fel
//return_to_fel:
// mov r0, #0x4
// mov r1, #'e'
// strb r1, [r0, #0]
// mov r1, #'G'
// strb r1, [r0, #1]
// mov r1, #'O'
// strb r1, [r0, #2]
// mov r1, #'N'
// strb r1, [r0, #3]
// mov r1, #'.'
// strb r1, [r0, #4]
// mov r1, #'F'
// strb r1, [r0, #5]
// mov r1, #'E'
// strb r1, [r0, #6]
// mov r1, #'L'
// strb r1, [r0, #7]
// ldr r0, =0x00000040
// ldr sp, [r0, #0]
// ldr lr, [r0, #4]
// ldr r1, [r0, #16]
// mcr p15, 0, r1, c1, c0, 0
// ldr r1, [r0, #12]
// mcr p15, 0, r1, c1, c0, 0
// ldr r1, [r0, #8]
// msr cpsr, r1
// bx lr
/*
* Exception handlers
*/
.align 5
undefined_instruction:
b .
.align 5
software_interrupt:
b .
.align 5
prefetch_abort:
b .
.align 5
data_abort:
b .
.align 5
not_used:
b .
.align 5
irq:
ldr sp, _stack_irq_end
sub sp, sp, #72
stmia sp, {r0 - r12}
add r8, sp, #60
stmdb r8, {sp, lr}^
str lr, [r8, #0]
mrs r6, spsr
str r6, [r8, #4]
str r0, [r8, #8]
mov r0, sp
bl arm32_do_irq
ldmia sp, {r0 - lr}^
mov r0, r0
ldr lr, [sp, #60]
add sp, sp, #72
subs pc, lr, #4
.align 5
fiq:
ldr sp, _stack_irq_end
sub sp, sp, #72
stmia sp, {r0 - r12}
add r8, sp, #60
stmdb r8, {sp, lr}^
str lr, [r8, #0]
mrs r6, spsr
str r6, [r8, #4]
str r0, [r8, #8]
mov r0, sp
bl arm32_do_fiq
ldmia sp, {r0 - lr}^
mov r0, r0
ldr lr, [sp, #60]
add sp, sp, #72
subs pc, lr, #4
/*
* The location of section
*/
.align 4
//_image_start:
// .long __image_start
//_image_end:
// .long __image_end
_data_shadow_start:
.long __data_shadow_start
_data_shadow_end:
.long __data_shadow_end
_data_start:
.long __data_start
_data_end:
.long __data_end
_bss_start:
.long __bss_start
_bss_end:
.long __bss_end
_stack_usr_end:
.long __stack_usr_end
_stack_und_end:
.long __stack_und_end
_stack_abt_end:
.long __stack_abt_end
_stack_irq_end:
.long __stack_irq_end
_stack_fiq_end:
.long __stack_fiq_end
_stack_srv_end:
.long __stack_srv_end可以跳到main()函数执行，但是下面的代码只能输出abc, 却没人办法输出test2134就死掉了
int main(int argc, char **argv) {
sys_uart_init();
sys_uart_putc('a');
sys_uart_putc('b');
sys_uart_putc('c');
// sys_mmu_init();
printf("test2134");
while(1);
return 0;
}所用LD文件如下
OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
OUTPUT_ARCH(arm)
ENTRY(_start)
STACK_USR_SIZE = 0x10000; /* 40k */
STACK_UND_SIZE = 0x10000;
STACK_ABT_SIZE = 0x10000;
STACK_IRQ_SIZE = 0x10000;
STACK_FIQ_SIZE = 0x10000;
STACK_SRV_SIZE = 0x10000; /* 160k */
MEMORY
{
/*
ram : org = 0x80000000, len = 8M
dma : org = 0x80800000, len = 8M
heap : org = 0x81000000, len = 16M
*/
ram : org = 0x80000100, len = 800K
dma : org = 0x80800000, len = 2M
heap : org = 0x80c00000, len = 2M
stack : org = 0x81000000, len = 1M
}
SECTIONS
{
/*
.bootloader :
{
PROVIDE(__bootloader_start = .);
PROVIDE(__image_start = .);
PROVIDE(__text_start = .);
Objects\start.o (.text)
Objects\memcpy.o (.text)
Objects\memset.o (.text)
Objects\sys-uart.o (.text)
Objects\sys-clock.o (.text)
Objects\sys-dram.o (.text)
Objects\sys-mmu.o (.text)
Objects\sys-spi-flash.o (.text)
Objects\sys-copyself.o (.text)
PROVIDE(__bootloader_end = .);
} > ram
__bootloader_size = SIZEOF(.bootloader);
*/
.text :
{
/*Objects\main.o (.text)*/
*(.text)
*(.text*)
*(.init.text)
*(.exit.text)
*(.glue*)
*(.note.gnu.build-id)
PROVIDE(__text_end = .);
} > ram
.initcall ALIGN(8) :
{
PROVIDE(__initcall_start = .);
KEEP(*(.initcall_0.text))
KEEP(*(.initcall_1.text))
KEEP(*(.initcall_2.text))
KEEP(*(.initcall_3.text))
KEEP(*(.initcall_4.text))
KEEP(*(.initcall_5.text))
KEEP(*(.initcall_6.text))
KEEP(*(.initcall_7.text))
KEEP(*(.initcall_8.text))
KEEP(*(.initcall_9.text))
PROVIDE(__initcall_end = .);
} > ram
.exitcall ALIGN(8) :
{
PROVIDE(__exitcall_start = .);
KEEP(*(.exitcall_9.text))
KEEP(*(.exitcall_8.text))
KEEP(*(.exitcall_7.text))
KEEP(*(.exitcall_6.text))
KEEP(*(.exitcall_5.text))
KEEP(*(.exitcall_4.text))
KEEP(*(.exitcall_3.text))
KEEP(*(.exitcall_2.text))
KEEP(*(.exitcall_1.text))
KEEP(*(.exitcall_0.text))
PROVIDE(__exitcall_end = .);
} > ram
.ksymtab ALIGN(8) :
{
PROVIDE(__ksymtab_start = .);
KEEP(*(.ksymtab.text))
PROVIDE(__ksymtab_end = .);
} > ram
.romdisk ALIGN(8) :
{
PROVIDE(__romdisk_start = .);
KEEP(*(.romdisk))
PROVIDE(__romdisk_end = .);
} > ram
.rodata ALIGN(8) :
{
PROVIDE(__rodata_start = .);
*(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*)))
PROVIDE(__rodata_end = .);
} > ram
.data_shadow ALIGN(8) :
{
PROVIDE(__data_shadow_start = .);
PROVIDE(__data_shadow_end = (. + SIZEOF(.data)));
PROVIDE(__image_end = __data_shadow_end);
} > ram
.data : AT(ADDR(.data_shadow))
{
PROVIDE(__data_start = .);
*(.data*)
. = ALIGN(8);
PROVIDE(__data_end = .);
} > ram
.ARM.exidx ALIGN(8) :
{
PROVIDE (__exidx_start = .);
*(.ARM.exidx*)
PROVIDE (__exidx_end = .);
} > ram
.ARM.extab ALIGN(8) :
{
PROVIDE (__extab_start = .);
*(.ARM.extab*)
PROVIDE (__extab_end = .);
} > ram
.bss ALIGN(8) (NOLOAD) :
{
PROVIDE(__bss_start = .);
*(.bss*)
*(.sbss*)
*(COMMON)
. = ALIGN(8);
PROVIDE(__bss_end = .);
} > ram
.stack ALIGN(8) (NOLOAD) :
{
PROVIDE(__stack_start = ORIGIN(stack));
PROVIDE(__stack_usr_start = __stack_start);
PROVIDE(__stack_usr_end = __stack_start + STACK_USR_SIZE);
PROVIDE(__stack_und_start = __stack_usr_end);
PROVIDE(__stack_und_end = __stack_usr_end + STACK_UND_SIZE);
. = ALIGN(8);
PROVIDE(__stack_abt_start = __stack_und_end);
PROVIDE(__stack_abt_end = __stack_und_end + STACK_ABT_SIZE);
. = ALIGN(8);
PROVIDE(__stack_irq_start = __stack_abt_end);
PROVIDE(__stack_irq_end = __stack_abt_end + STACK_IRQ_SIZE);
. = ALIGN(8);
PROVIDE(__stack_fiq_start = __stack_irq_end);
PROVIDE(__stack_fiq_end = __stack_irq_end + STACK_FIQ_SIZE);
. = ALIGN(8);
PROVIDE(__stack_srv_start = __stack_fiq_end);
PROVIDE(__stack_srv_end = __stack_fiq_end + STACK_SRV_SIZE);
. = ALIGN(8);
PROVIDE(__stack_end = __stack_srv_end);
} > stack
.dma ALIGN(8) (NOLOAD) :
{
PROVIDE(__dma_start = ORIGIN(dma));
PROVIDE(__dma_end = ORIGIN(dma) + LENGTH(dma));
} > dma
.heap ALIGN(8) (NOLOAD) :
{
PROVIDE(__heap_start = ORIGIN(heap));
PROVIDE(__heap_end = ORIGIN(heap) + LENGTH(heap));
} > heap
.stab 0 : { *(.stab) }
.stabstr 0 : { *(.stabstr) }
.stab.excl 0 : { *(.stab.excl) }
.stab.exclstr 0 : { *(.stab.exclstr) }
.stab.index 0 : { *(.stab.index) }
.stab.indexstr 0 : { *(.stab.indexstr) }
.comment 0 : { *(.comment) }
.debug_abbrev 0 : { *(.debug_abbrev) }
.debug_info 0 : { *(.debug_info) }
.debug_line 0 : { *(.debug_line) }
.debug_pubnames 0 : { *(.debug_pubnames) }
.debug_aranges 0 : { *(.debug_aranges) }
}最近编辑记录 shawn.d (2021-07-08 12:30:22)
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