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|
/*
* linux/arch/arm/boot/compressed/head.S
*
* Copyright (C) 1996-1999 Russell King
*/
#include <linux/linkage.h>
.section ".start", #alloc, #execinstr
/*
* sort out different calling conventions
*/
.align
start:
.type start,#function
.rept 8
mov r0, r0
.endr
b 1f
.word 0x016f2818 @ Magic numbers to help the loader
.word start
1:
/*
* some architecture specific code can
* be inserted by the linker here
*/
.text
1: teq r0, #0
bne 1b
mov r7, r1 @ save architecture ID
mrc p15, 0, r6, c0, c0 @ get processor ID
adr r2, LC0
ldmia r2, {r2, r3, r4, r5, sp}
mov r0, #0
1: str r0, [r2], #4 @ clear bss
str r0, [r2], #4
str r0, [r2], #4
str r0, [r2], #4
cmp r2, r3
blt 1b
mov r1, sp @ malloc space above stack
add r2, sp, #0x10000 @ 64k max
teq r4, r5 @ will we overwrite ourselves?
moveq r5, r2
movne r5, r4
mov r0, r5
mov r3, r7
bl SYMBOL_NAME(decompress_kernel)
teq r4, r5 @ do we need to relocate
beq call_kernel @ the kernel?
add r0, r0, #127
bic r0, r0, #127 @ align the kernel length
/*
* r0 = decompressed kernel length
* r1-r3 = unused
* r4 = kernel execution address
* r5 = decompressed kernel start
* r6 = processor ID
* r7 = architecture ID
* r8-r14 = unused
*/
add r1, r5, r0 @ end of decompressed kernel
adr r2, reloc_start
adr r3, reloc_end
1: ldmia r2!, {r8 - r13} @ copy relocation code
stmia r1!, {r8 - r13}
ldmia r2!, {r8 - r13}
stmia r1!, {r8 - r13}
cmp r2, r3
blt 1b
eor r1, r6, #0x44 << 24 @ SA-110 or SA-1100?
eor r1, r1, #0x01 << 16
eor r1, r1, #0xa1 << 8
movs r1, r1, lsr #5
mcreq p15, 0, r1, c7, c7, 0 @ flush I & D-cache
mcreq p15, 0, r1, c7, c10, 4 @ drain WB
add pc, r5, r0 @ call relocation code
/*
* r0 = decompressed kernel length
* r1-r3 = unused
* r4 = kernel execution address
* r5 = decompressed kernel start
* r6 = processor ID
* r7 = architecture ID
* r8-r14 = unused
*/
reloc_start: add r8, r5, r0
#if 0
mov r0, #'\n'
bl putc
mov r0, r6
mov r1, #8
bl phex
mov r0, #':'
bl putc
mov r0, r5
mov r1, #8
bl phex
mov r0, #'-'
bl putc
mov r0, r8
mov r1, #8
bl phex
mov r0, #'>'
bl putc
mov r0, r4
mov r1, #8
bl phex
mov r0, #'\n'
bl putc
#endif
mov r0, r8
mov r1, r4
1:
.rept 4
ldmia r5!, {r2, r3, r8 - r13} @ relocate kernel
stmia r1!, {r2, r3, r8 - r13}
.endr
cmp r5, r0
blt 1b
#if 0
mov r8, r0
mov r0, r5
mov r1, #8
bl phex
mov r0, #'-'
bl putc
mov r0, r8
mov r1, #8
bl phex
mov r0, #'\n'
bl putc
mov r0, r4
bl memdump
#endif
eor r0, r6, #0x44 << 24 @ SA-110 or SA-1100?
eor r0, r0, #0x01 << 16
eor r0, r0, #0xa1 << 8
movs r0, r0, lsr #5
mcreq p15, 0, r0, c7, c7, 0 @ flush I cache
mcreq p15, 0, r1, c7, c10, 4 @ drain WB
call_kernel: mov r0, #0
mov r1, r7 @ restore architecture number
mov pc, r4 @ call kernel
phexbuf: .space 12
#if 0
.macro loadsp, rb
mov \rb, #0x7c000000
.endm
.macro writeb, rb
strb \rb, [r3, #0x3f8]
.endm
#else
.macro loadsp, rb
mov \rb, #0x03000000
orr \rb, \rb, #0x00010000
.endm
.macro writeb, rb
strb \rb, [r3, #0x3f8 << 2]
.endm
#endif
phex: adr r3, phexbuf
mov r2, #0
strb r2, [r3, r1]
1: subs r1, r1, #1
movmi r0, r3
bmi puts
and r2, r0, #15
mov r0, r0, lsr #4
cmp r2, #10
addge r2, r2, #7
add r2, r2, #'0'
strb r2, [r3, r1]
b 1b
puts: loadsp r3
1: ldrb r2, [r0], #1
teq r2, #0
moveq pc, lr
2: writeb r2
mov r1, #0x00020000
3: subs r1, r1, #1
bne 3b
teq r2, #'\n'
moveq r2, #'\r'
beq 2b
teq r0, #0
bne 1b
mov pc, lr
putc:
mov r2, r0
mov r0, #0
loadsp r3
b 2b
memdump: mov r12, r0
mov r10, lr
mov r1, #8
bl phex
mov r0, #'\n'
bl putc
mov r11, #0
2: mov r0, r11, lsl #2
mov r1, #4
bl phex
mov r0, #':'
bl putc
1: mov r0, #' '
bl putc
ldr r0, [r12, r11, lsl #2]
mov r1, #8
bl phex
and r0, r11, #7
teq r0, #3
moveq r0, #' '
bleq putc
and r0, r11, #7
add r11, r11, #1
teq r0, #7
bne 1b
mov r0, #'\n'
bl putc
cmp r11, #64
blt 2b
mov pc, r10
reloc_end:
LC0: .word __bss_start
.word _end
.word _load_addr
.word _start
.word user_stack+4096
.align
.section ".stack"
user_stack: .space 4096
|
