112 lines
2.5 KiB
ArmAsm
112 lines
2.5 KiB
ArmAsm
|
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
||
|
/*
|
||
|
* Code to process dynamic relocations in the kernel.
|
||
|
*
|
||
|
* Copyright 2008 Paul Mackerras, IBM Corp.
|
||
|
*/
|
||
|
|
||
|
#include <asm/ppc_asm.h>
|
||
|
|
||
|
RELA = 7
|
||
|
RELASZ = 8
|
||
|
RELAENT = 9
|
||
|
R_PPC64_RELATIVE = 22
|
||
|
R_PPC64_UADDR64 = 43
|
||
|
|
||
|
/*
|
||
|
* r3 = desired final address of kernel
|
||
|
*/
|
||
|
_GLOBAL(relocate)
|
||
|
mflr r0
|
||
|
bcl 20,31,$+4
|
||
|
0: mflr r12 /* r12 has runtime addr of label 0 */
|
||
|
mtlr r0
|
||
|
ld r11,(p_dyn - 0b)(r12)
|
||
|
add r11,r11,r12 /* r11 has runtime addr of .dynamic section */
|
||
|
ld r9,(p_rela - 0b)(r12)
|
||
|
add r9,r9,r12 /* r9 has runtime addr of .rela.dyn section */
|
||
|
ld r10,(p_st - 0b)(r12)
|
||
|
add r10,r10,r12 /* r10 has runtime addr of _stext */
|
||
|
ld r13,(p_sym - 0b)(r12)
|
||
|
add r13,r13,r12 /* r13 has runtime addr of .dynsym */
|
||
|
|
||
|
/*
|
||
|
* Scan the dynamic section for the RELA, RELASZ and RELAENT entries.
|
||
|
*/
|
||
|
li r7,0
|
||
|
li r8,0
|
||
|
.Ltags:
|
||
|
ld r6,0(r11) /* get tag */
|
||
|
cmpdi r6,0
|
||
|
beq .Lend_of_list /* end of list */
|
||
|
cmpdi r6,RELA
|
||
|
bne 2f
|
||
|
ld r7,8(r11) /* get RELA pointer in r7 */
|
||
|
b 4f
|
||
|
2: cmpdi r6,RELASZ
|
||
|
bne 3f
|
||
|
ld r8,8(r11) /* get RELASZ value in r8 */
|
||
|
b 4f
|
||
|
3: cmpdi r6,RELAENT
|
||
|
bne 4f
|
||
|
ld r12,8(r11) /* get RELAENT value in r12 */
|
||
|
4: addi r11,r11,16
|
||
|
b .Ltags
|
||
|
.Lend_of_list:
|
||
|
cmpdi r7,0 /* check we have RELA, RELASZ, RELAENT */
|
||
|
cmpdi cr1,r8,0
|
||
|
beq .Lout
|
||
|
beq cr1,.Lout
|
||
|
cmpdi r12,0
|
||
|
beq .Lout
|
||
|
|
||
|
/*
|
||
|
* Work out linktime address of _stext and hence the
|
||
|
* relocation offset to be applied.
|
||
|
* cur_offset [r7] = rela.run [r9] - rela.link [r7]
|
||
|
* _stext.link [r10] = _stext.run [r10] - cur_offset [r7]
|
||
|
* final_offset [r3] = _stext.final [r3] - _stext.link [r10]
|
||
|
*/
|
||
|
subf r7,r7,r9 /* cur_offset */
|
||
|
subf r10,r7,r10
|
||
|
subf r3,r10,r3 /* final_offset */
|
||
|
|
||
|
/*
|
||
|
* Run through the list of relocations and process the
|
||
|
* R_PPC64_RELATIVE and R_PPC64_UADDR64 ones.
|
||
|
*/
|
||
|
divd r8,r8,r12 /* RELASZ / RELAENT */
|
||
|
mtctr r8
|
||
|
.Lrels: ld r0,8(r9) /* ELF64_R_TYPE(reloc->r_info) */
|
||
|
cmpdi r0,R_PPC64_RELATIVE
|
||
|
bne .Luaddr64
|
||
|
ld r6,0(r9) /* reloc->r_offset */
|
||
|
ld r0,16(r9) /* reloc->r_addend */
|
||
|
b .Lstore
|
||
|
.Luaddr64:
|
||
|
srdi r14,r0,32 /* ELF64_R_SYM(reloc->r_info) */
|
||
|
clrldi r0,r0,32
|
||
|
cmpdi r0,R_PPC64_UADDR64
|
||
|
bne .Lnext
|
||
|
ld r6,0(r9)
|
||
|
ld r0,16(r9)
|
||
|
mulli r14,r14,24 /* 24 == sizeof(elf64_sym) */
|
||
|
add r14,r14,r13 /* elf64_sym[ELF64_R_SYM] */
|
||
|
ld r14,8(r14)
|
||
|
add r0,r0,r14
|
||
|
.Lstore:
|
||
|
add r0,r0,r3
|
||
|
stdx r0,r7,r6
|
||
|
.Lnext:
|
||
|
add r9,r9,r12
|
||
|
bdnz .Lrels
|
||
|
.Lout:
|
||
|
blr
|
||
|
|
||
|
.balign 8
|
||
|
p_dyn: .8byte __dynamic_start - 0b
|
||
|
p_rela: .8byte __rela_dyn_start - 0b
|
||
|
p_sym: .8byte __dynamic_symtab - 0b
|
||
|
p_st: .8byte _stext - 0b
|
||
|
|