linux-sg2042/arch/h8300/kernel/head_rom.S

112 lines
1.7 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/init.h>
#include <asm/thread_info.h>
#if defined(CONFIG_CPU_H8300H)
.h8300h
#define SYSCR 0xfee012
#define IRAMTOP 0xffff20
#define NR_INT 64
#endif
#if defined(CONFIG_CPU_H8S)
.h8300s
#define INTCR 0xffff31
#define IRAMTOP 0xffc000
#define NR_INT 128
#endif
__HEAD
.global _start
_start:
mov.l #IRAMTOP,sp
#if !defined(CONFIG_H8300H_SIM) && \
!defined(CONFIG_H8S_SIM)
jsr @lowlevel_init
/* copy .data */
mov.l #_begin_data,er5
mov.l #_sdata,er6
mov.l #_edata,er4
sub.l er6,er4
shlr.l er4
shlr.l er4
1:
mov.l @er5+,er0
mov.l er0,@er6
adds #4,er6
dec.l #1,er4
bne 1b
/* .bss clear */
mov.l #_sbss,er5
mov.l #_ebss,er4
sub.l er5,er4
shlr er4
shlr er4
sub.l er0,er0
1:
mov.l er0,@er5
adds #4,er5
dec.l #1,er4
bne 1b
#else
/* get cmdline from gdb */
jsr @0xcc
;; er0 - argc
;; er1 - argv
mov.l #command_line,er3
adds #4,er1
dec.l #1,er0
beq 4f
1:
mov.l @er1+,er2
2:
mov.b @er2+,r4l
beq 3f
mov.b r4l,@er3
adds #1,er3
bra 2b
3:
mov.b #' ',r4l
mov.b r4l,@er3
adds #1,er3
dec.l #1,er0
bne 1b
subs #1,er3
mov.b #0,r4l
mov.b r4l,@er3
4:
#endif
sub.l er0,er0
jsr @h8300_fdt_init
/* linux kernel start */
#if defined(CONFIG_CPU_H8300H)
ldc #0xd0,ccr /* running kernel */
mov.l #SYSCR,er0
bclr #3,@er0
#endif
#if defined(CONFIG_CPU_H8S)
ldc #0x07,exr
bclr #4,@INTCR:8
bset #5,@INTCR:8 /* Interrupt mode 2 */
ldc #0x90,ccr /* running kernel */
#endif
mov.l #init_thread_union,sp
add.l #0x2000,sp
jsr @start_kernel
1:
bra 1b
#if defined(CONFIG_ROMKERNEL)
/* interrupt vector */
.section .vectors,"ax"
.long _start
.long _start
vector = 2
.rept NR_INT - 2
.long _interrupt_redirect_table+vector*4
vector = vector + 1
.endr
#endif
.end