1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * Code to process dynamic relocations in the kernel.
  4 *
  5 * Copyright 2008 Paul Mackerras, IBM Corp.
  6 */
  7
  8#include <asm/ppc_asm.h>
  9
 10RELA = 7
 11RELASZ = 8
 12RELAENT = 9
 13R_PPC64_RELATIVE = 22
 14R_PPC64_UADDR64 = 43
 15
 16/*
 17 * r3 = desired final address of kernel
 18 */
 19_GLOBAL(relocate)
 20	mflr	r0
 21	bcl	20,31,$+4
 220:	mflr	r12		/* r12 has runtime addr of label 0 */
 23	mtlr	r0
 24	ld	r11,(p_dyn - 0b)(r12)
 25	add	r11,r11,r12	/* r11 has runtime addr of .dynamic section */
 26	ld	r9,(p_rela - 0b)(r12)
 27	add	r9,r9,r12	/* r9 has runtime addr of .rela.dyn section */
 28	ld	r10,(p_st - 0b)(r12)
 29	add	r10,r10,r12	/* r10 has runtime addr of _stext */
 30	ld	r4,(p_sym - 0b)(r12)
 31	add	r4,r4,r12	/* r4 has runtime addr of .dynsym */
 32
 33	/*
 34	 * Scan the dynamic section for the RELA, RELASZ and RELAENT entries.
 35	 */
 36	li	r7,0
 37	li	r8,0
 38.Ltags:
 39	ld	r6,0(r11)	/* get tag */
 40	cmpdi	r6,0
 41	beq	.Lend_of_list		/* end of list */
 42	cmpdi	r6,RELA
 43	bne	2f
 44	ld	r7,8(r11)	/* get RELA pointer in r7 */
 45	b	4f
 462:	cmpdi	r6,RELASZ
 
 47	bne	3f
 48	ld	r8,8(r11)	/* get RELASZ value in r8 */
 49	b	4f
 503:	cmpdi	r6,RELAENT
 51	bne	4f
 52	ld	r12,8(r11)	/* get RELAENT value in r12 */
 534:	addi	r11,r11,16
 54	b	.Ltags
 55.Lend_of_list:
 56	cmpdi	r7,0		/* check we have RELA, RELASZ, RELAENT */
 57	cmpdi	cr1,r8,0
 58	beq	.Lout
 59	beq	cr1,.Lout
 60	cmpdi	r12,0
 61	beq	.Lout
 62
 63	/*
 64	 * Work out linktime address of _stext and hence the
 65	 * relocation offset to be applied.
 66	 * cur_offset [r7] = rela.run [r9] - rela.link [r7]
 67	 * _stext.link [r10] = _stext.run [r10] - cur_offset [r7]
 68	 * final_offset [r3] = _stext.final [r3] - _stext.link [r10]
 69	 */
 70	subf	r7,r7,r9	/* cur_offset */
 71	subf	r10,r7,r10
 72	subf	r3,r10,r3	/* final_offset */
 73
 74	/*
 75	 * Run through the list of relocations and process the
 76	 * R_PPC64_RELATIVE and R_PPC64_UADDR64 ones.
 77	 */
 78	divd	r8,r8,r12	/* RELASZ / RELAENT */
 79	mtctr	r8
 80.Lrels:	ld	r0,8(r9)		/* ELF64_R_TYPE(reloc->r_info) */
 81	cmpdi	r0,R_PPC64_RELATIVE
 82	bne	.Luaddr64
 83	ld	r6,0(r9)	/* reloc->r_offset */
 84	ld	r0,16(r9)	/* reloc->r_addend */
 85	b	.Lstore
 86.Luaddr64:
 87	srdi	r5,r0,32	/* ELF64_R_SYM(reloc->r_info) */
 88	clrldi	r0,r0,32
 89	cmpdi	r0,R_PPC64_UADDR64
 90	bne	.Lnext
 91	ld	r6,0(r9)
 92	ld	r0,16(r9)
 93	mulli	r5,r5,24	/* 24 == sizeof(elf64_sym) */
 94	add	r5,r5,r4	/* elf64_sym[ELF64_R_SYM] */
 95	ld	r5,8(r5)
 96	add	r0,r0,r5
 97.Lstore:
 98	add	r0,r0,r3
 99	stdx	r0,r7,r6
100.Lnext:
101	add	r9,r9,r12
102	bdnz	.Lrels
103.Lout:
104	blr
105
106.balign 8
107p_dyn:	.8byte	__dynamic_start - 0b
108p_rela:	.8byte	__rela_dyn_start - 0b
109p_sym:		.8byte __dynamic_symtab - 0b
110p_st:	.8byte	_stext - 0b
111

 1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2/*
 3 * Code to process dynamic relocations in the kernel.
 4 *
 5 * Copyright 2008 Paul Mackerras, IBM Corp.
 6 */
 7
 8#include <asm/ppc_asm.h>
 9
10RELA = 7
11RELACOUNT = 0x6ffffff9
 
12R_PPC64_RELATIVE = 22
 
13
14/*
15 * r3 = desired final address of kernel
16 */
17_GLOBAL(relocate)
18	mflr	r0
19	bcl	20,31,$+4
200:	mflr	r12		/* r12 has runtime addr of label 0 */
21	mtlr	r0
22	ld	r11,(p_dyn - 0b)(r12)
23	add	r11,r11,r12	/* r11 has runtime addr of .dynamic section */
24	ld	r9,(p_rela - 0b)(r12)
25	add	r9,r9,r12	/* r9 has runtime addr of .rela.dyn section */
26	ld	r10,(p_st - 0b)(r12)
27	add	r10,r10,r12	/* r10 has runtime addr of _stext */
 
 
28
29	/*
30	 * Scan the dynamic section for the RELA and RELACOUNT entries.
31	 */
32	li	r7,0
33	li	r8,0
341:	ld	r6,0(r11)	/* get tag */
 
35	cmpdi	r6,0
36	beq	4f		/* end of list */
37	cmpdi	r6,RELA
38	bne	2f
39	ld	r7,8(r11)	/* get RELA pointer in r7 */
40	b	3f
412:	addis	r6,r6,(-RELACOUNT)@ha
42	cmpdi	r6,RELACOUNT@l
43	bne	3f
44	ld	r8,8(r11)	/* get RELACOUNT value in r8 */
453:	addi	r11,r11,16
46	b	1b
474:	cmpdi	r7,0		/* check we have both RELA and RELACOUNT */
 
 
 
 
 
48	cmpdi	cr1,r8,0
49	beq	6f
50	beq	cr1,6f
 
 
51
52	/*
53	 * Work out linktime address of _stext and hence the
54	 * relocation offset to be applied.
55	 * cur_offset [r7] = rela.run [r9] - rela.link [r7]
56	 * _stext.link [r10] = _stext.run [r10] - cur_offset [r7]
57	 * final_offset [r3] = _stext.final [r3] - _stext.link [r10]
58	 */
59	subf	r7,r7,r9	/* cur_offset */
60	subf	r10,r7,r10
61	subf	r3,r10,r3	/* final_offset */
62
63	/*
64	 * Run through the list of relocations and process the
65	 * R_PPC64_RELATIVE ones.
66	 */
 
67	mtctr	r8
685:	ld	r0,8(9)		/* ELF64_R_TYPE(reloc->r_info) */
69	cmpdi	r0,R_PPC64_RELATIVE
70	bne	6f
71	ld	r6,0(r9)	/* reloc->r_offset */
72	ld	r0,16(r9)	/* reloc->r_addend */
 
 
 
 
 
 
 
 
 
 
 
 
 
73	add	r0,r0,r3
74	stdx	r0,r7,r6
75	addi	r9,r9,24
76	bdnz	5b
77
786:	blr
 
79
80.balign 8
81p_dyn:	.8byte	__dynamic_start - 0b
82p_rela:	.8byte	__rela_dyn_start - 0b
 
83p_st:	.8byte	_stext - 0b
84