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# // Copyright 2024-2025, Amlal El Mahrouss (amlal@nekernel.org)
# // Distributed under the Apache Software License, Version 2.0. (See accompanying
# // file LICENSE_1_0.txt or copy at http://www.apache.org/licenses/LICENSE-2.0)
# // Official repository: https://github.com/nekernel-org/neboot
/* Code starts at 8M, everything below is memory mapped hardware. */
.option norvc
.extern cb_start_exec
.global cb_reset_vector
.global cb_hart_present
.section .init
.align 4
cb_reset_vector:
.cfi_startproc
csrr t0, mhartid
beqz t0, cb_start_exec_asm
j cb_start_other
.cfi_endproc
cb_start_exec_asm:
lw t0, __nb_hart_counter
lw t1, cb_boot_processor_ready
not t0, t0
addi t1, zero, 1
.option push
.option norelax
la gp, cb_global_pointer
.option pop
la sp, cb_stack_end
la t5, _bss_start
la t6, _bss_end
crt0_bss_clear:
sd zero, (t5)
addi t5, t5, 8
bgeu t5, t6, crt0_bss_clear
j cb_start_exec
j cb_hang
cb_start_other:
lw t1, cb_boot_processor_ready
cb_start_other_wait:
beq t1, zero, cb_start_other_wait
la t0, cb_stack_list
ld t1, cb_stack_align
mv sp, t0
add t0, zero, t1
j cb_hang
.global cb_start_rom
.global cb_start_context
cb_start_context:
mv ra, zero
add ra, zero, a1
mret
.equ NB_BOOT_ADDR, 0x80020000
cb_start_rom:
li x5, NB_BOOT_ADDR
mv ra, zero
add ra, zero, t0
mret
cb_hang:
j cb_start_exec
L0:
wfi
j L0
.bss
.align 4
cb_hart_present:
.long 0
.data
.align 4
cb_stack_list:
.long cb_memory_end
cb_stack_align:
.word 0x8000
__nb_max_harts:
.word 2
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