66 lines
1.0 KiB
ArmAsm
66 lines
1.0 KiB
ArmAsm
.section .vectors, "ax", %progbits
|
|
.align 3
|
|
.global reset
|
|
reset:
|
|
b _start
|
|
b _panic
|
|
|
|
.section .text.start, "ax", %progbits
|
|
.align 3
|
|
.global _start
|
|
.extern main
|
|
_start:
|
|
/* Mask IRQ + FIQ, enter SVC mode. */
|
|
msr cpsr_f, #0xC0
|
|
msr cpsr_cf, #0xD3
|
|
|
|
/* Set the stack pointer. */
|
|
ldr sp, =__stack_top
|
|
|
|
/* Zero .bss. */
|
|
ldr r0, =__bss_start__
|
|
ldr r1, =__bss_end__
|
|
mov r2, #0
|
|
1:
|
|
cmp r0, r1
|
|
bge 2f
|
|
str r2, [r0], #4
|
|
b 1b
|
|
2:
|
|
|
|
/* Run global constructors. */
|
|
ldr r4, =__init_array_start
|
|
ldr r5, =__init_array_end
|
|
3:
|
|
cmp r4, r5
|
|
bge 4f
|
|
ldr r0, [r4], #4
|
|
mov lr, pc
|
|
bx r0
|
|
b 3b
|
|
4:
|
|
|
|
bl main
|
|
|
|
.global _panic
|
|
_panic:
|
|
ldr r0, =0x70006040 /* UART_B_BASE */
|
|
adr r3, _panic_msg
|
|
7:
|
|
ldrb r1, [r3], #1
|
|
cmp r1, #0
|
|
beq _panic_hang
|
|
8:
|
|
ldr r2, [r0, #0x14] /* UART_LSR */
|
|
tst r2, #0x20 /* UART_LSR_THRE */
|
|
beq 8b
|
|
str r1, [r0]
|
|
b 7b
|
|
|
|
_panic_msg:
|
|
.asciz "[bpmpfw] PANIC\n"
|
|
.align 2
|
|
|
|
_panic_hang:
|
|
b _panic_hang
|