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/*
* linux/arch/arm/boot/compressed/head-nexuspci.S
*
* Copyright (C) 1996, 1997, 1998 Philip Blundell
*
* NexusPCI is unusual because we don't have a bootloader -- the kernel is
* run directly out of ROM at the moment. Maybe this will change one day and
* then this file can go away.
*
*/
.text
.globl _start
_start: b reset
b undefined
b undefined
b undefined
b undefined
b undefined
b undefined
b undefined
b go_uncompress
reset: mov r2, #0x20000000 @ LED off
mov r1, #0x1a
str r1, [r2]
mov r2, #0x10000000 @ SCC init
mov r1, #42
strb r1, [r2, #8]
mov r1, #48
strb r1, [r2, #8]
mov r1, #16
strb r1, [r2, #8]
mov r1, #0x93
strb r1, [r2, #0]
mov r1, #0x17
strb r1, [r2, #0]
mov r1, #0xbb
strb r1, [r2, #0x4]
mov r1, #0x78
strb r1, [r2, #0x10]
mov r1, #160
strb r1, [r2, #0x8]
mov r1, #5
strb r1, [r2, #0x8]
ldr r2, =_start
ldr r3, =_edata
mov r8, r2
mov r0, #0
1:
ldmia r0!, {r4, r5, r6, r7}
stmia r2!, {r4, r5, r6, r7}
cmp r2, r3
ble 1b
ldr r3, =_edata
ldr r1, =_end
mov r2, #0
1:
strb r2, [r3]
cmp r3, r1
beq 2f
add r3, r3, #1
b 1b
2:
add pc, r8, #0x20
undefined: ldr r4, =undef_msg
1: ldrb r0, [r4], #1
movs r0, r0
2: beq 2b
bl _ll_write_char
b 1b
undef_msg: .ascii "Undefined instruction (or other problem)\000"
.align 4
/*
* Uncompress the kernel
*/
go_uncompress:
mov r0, #0x40000000
ldr sp, =user_stack
add sp, sp, #4096
bl decompress_kernel
mov r2, #0x40000000
mov r0, #0
mov r1, #3
add pc, r2, #0x20 @ call via EXEC entry
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