original_kernel/arch/arm/kernel/relocate_kernel.S

79 lines
1.3 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* relocate_kernel.S - put the kernel image in place to boot
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/kexec.h>
.align 3 /* not needed for this code, but keeps fncpy() happy */
ENTRY(relocate_new_kernel)
adr r7, relocate_new_kernel_end
ldr r0, [r7, #KEXEC_INDIR_PAGE]
ldr r1, [r7, #KEXEC_START_ADDR]
/*
* If there is no indirection page (we are doing crashdumps)
* skip any relocation.
*/
cmp r0, #0
beq 2f
0: /* top, read another word for the indirection page */
ldr r3, [r0],#4
/* Is it a destination page. Put destination address to r4 */
tst r3,#1
beq 1f
bic r4,r3,#1
b 0b
1:
/* Is it an indirection page */
tst r3,#2
beq 1f
bic r0,r3,#2
b 0b
1:
/* are we done ? */
tst r3,#4
beq 1f
b 2f
1:
/* is it source ? */
tst r3,#8
beq 0b
bic r3,r3,#8
mov r6,#1024
9:
ldr r5,[r3],#4
str r5,[r4],#4
subs r6,r6,#1
bne 9b
b 0b
2:
/* Jump to relocated kernel */
mov lr, r1
mov r0, #0
ldr r1, [r7, #KEXEC_MACH_TYPE]
ldr r2, [r7, #KEXEC_R2]
ARM( ret lr )
THUMB( bx lr )
ENDPROC(relocate_new_kernel)
.align 3
relocate_new_kernel_end:
.globl relocate_new_kernel_size
relocate_new_kernel_size:
.long relocate_new_kernel_end - relocate_new_kernel