linux/arch/powerpc/kernel/reloc_64.S
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

85 lines
1.8 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
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