89 lines
2.1 KiB
ArmAsm
89 lines
2.1 KiB
ArmAsm
|
/*
|
||
|
|
* Code to process dynamic relocations in the kernel.
|
||
|
|
*
|
||
|
|
* Copyright 2008 Paul Mackerras, IBM Corp.
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or
|
||
|
|
* modify it under the terms of the GNU General Public License
|
||
|
|
* as published by the Free Software Foundation; either version
|
||
|
|
* 2 of the License, or (at your option) any later version.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <asm/ppc_asm.h>
|
||
|
|
|
||
|
|
RELA = 7
|
||
|
|
RELACOUNT = 0x6ffffff9
|
||
|
|
R_PPC64_RELATIVE = 22
|
||
|
|
|
||
|
|
/*
|
||
|
|
* 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 */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Scan the dynamic section for the RELA and RELACOUNT entries.
|
||
|
|
*/
|
||
|
|
li r7,0
|
||
|
|
li r8,0
|
||
|
|
1: ld r6,0(r11) /* get tag */
|
||
|
|
cmpdi r6,0
|
||
|
|
beq 4f /* end of list */
|
||
|
|
cmpdi r6,RELA
|
||
|
|
bne 2f
|
||
|
|
ld r7,8(r11) /* get RELA pointer in r7 */
|
||
|
|
b 3f
|
||
|
|
2: addis r6,r6,(-RELACOUNT)@ha
|
||
|
|
cmpdi r6,RELACOUNT@l
|
||
|
|
bne 3f
|
||
|
|
ld r8,8(r11) /* get RELACOUNT value in r8 */
|
||
|
|
3: addi r11,r11,16
|
||
|
|
b 1b
|
||
|
|
4: cmpdi r7,0 /* check we have both RELA and RELACOUNT */
|
||
|
|
cmpdi cr1,r8,0
|
||
|
|
beq 6f
|
||
|
|
beq cr1,6f
|
||
|
|
|
||
|
|
/*
|
||
|
|
* 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 ones.
|
||
|
|
*/
|
||
|
|
mtctr r8
|
||
|
|
5: ld r0,8(9) /* ELF64_R_TYPE(reloc->r_info) */
|
||
|
|
cmpdi r0,R_PPC64_RELATIVE
|
||
|
|
bne 6f
|
||
|
|
ld r6,0(r9) /* reloc->r_offset */
|
||
|
|
ld r0,16(r9) /* reloc->r_addend */
|
||
|
|
add r0,r0,r3
|
||
|
|
stdx r0,r7,r6
|
||
|
|
addi r9,r9,24
|
||
|
|
bdnz 5b
|
||
|
|
|
||
|
|
6: blr
|
||
|
|
|
||
|
|
.balign 8
|
||
|
|
p_dyn: .8byte __dynamic_start - 0b
|
||
|
|
p_rela: .8byte __rela_dyn_start - 0b
|
||
|
|
p_st: .8byte _stext - 0b
|
||
|
|
|