Raspberry Pi | Error: backward ref to unknown label "1:"
Posted: Wed Jun 09, 2021 2:39 pm
Hello I am trying to make a raspberry pi OS from scratch but I get this error for the boot.s file when building with a makefile:
Whenever I look up the error it seems to be that the script cannot figure out that its supposed to be a number or something like that.
Sorry if this something only an asm noob could miss.
Boot.s Script:
Anyways thanks in advance.
Code: Select all
..//src/kernel/boot.s: Assembler messages:
..//src/kernel/boot.s:32: Error: backward ref to unknown label "1:"
make: *** [Makefile:95: ..//build/objects/boot.o] Error 1Sorry if this something only an asm noob could miss.
Boot.s Script:
Code: Select all
// AArch64 mode
// To keep this in the first portion of the binary.
.section ".text.boot"
// Make _start global.
.globl _start
.org 0x80000
// Entry point for the kernel. Registers:
// x0 -> 32 bit pointer to DTB in memory (primary core only) / 0 (secondary cores)
// x1 -> 0
// x2 -> 0
// x3 -> 0
// x4 -> 32 bit kernel entry point, _start location
_start:
// set stack before our code
ldr x5, =_start
mov sp, x5
// clear bss
ldr x5, =__bss_start
ldr w6, =__bss_size
3: cbz w6, 4f
str xzr, [x5], #8
sub w6, w6, #1
cbnz w6, 3b
// jump to C code, should not return
4: bl kernel_main
// for failsafe, halt this core too
b 1b Anyways thanks in advance.