begin.S revision 851e68a2402fa414544e66650e09dfdaac813e51 
1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <private/bionic_asm.h>
30
31#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
32#define ELF_DYNSZ       8
33#define ELF_DYN_TAG     0
34#define ELF_DYN_VAL     4
35#define GOTENT_SZ       4
36#else
37#define ELF_DYNSZ       16
38#define ELF_DYN_TAG     0
39#define ELF_DYN_VAL     8
40#define GOTENT_SZ       8
41#endif
42
43    .text
44    .align	4
45    .type	__start,@function
46
47    .ent	__start
48    .globl	__start
49__start:
50    .set	noreorder
51    bal		1f
52     nop
531:
54#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
55    .cpload	ra
56#else
57    .cpsetup	ra, $0, 1b
58#endif
59    .set	reorder
60
61    /* Discover the load address */
62    LA		t0, 1b
63    PTR_SUBU	t0, ra, t0
64
65#define DT_PLTGOT 3
66#define DT_MIPS_LOCAL_GOTNO 0x7000000a
67
68    /* Search dynamic table for DT_MIPS_LOCAL_GOTNO and DT_PLTGOT values */
69    LA		t1, _DYNAMIC
70    PTR_ADDU	t1, t0
71    LI		t3, DT_PLTGOT
72    LI		ta0, DT_MIPS_LOCAL_GOTNO
730:
74    REG_L	t2, ELF_DYN_TAG(t1)
75    beqz	t2, .Lrelocate_local_got
76
77    bne		t2, t3, 1f	/* DT_PLTGOT? */
78    REG_L	s0, ELF_DYN_VAL(t1)
79    PTR_ADDU	s0, t0
80    b		2f
81
821:
83    bne		t2, ta0, 2f    /* DT_MIPS_LOCAL_GOTNO? */
84    REG_L	s1, ELF_DYN_VAL(t1)
85
862:  PTR_ADDU    t1, ELF_DYNSZ
87    b		0b
88
89.Lrelocate_local_got:
90    /*
91     * Relocate the local GOT entries
92     * got[0] is address of lazy resolver function
93     * got[1] may be used for a GNU extension
94     */
95
96    PTR_ADDU	s0, GOTENT_SZ
97    SUBU	s1, 1
98    PTR_L	t1, (s0)
99    bgez	t1, 9f
100    PTR_ADDU	s0, GOTENT_SZ
101    SUBU	s1, 1
102    b		9f
103
1041:  PTR_L	t1, (s0)
105    PTR_ADDU	t1, t0
106    PTR_S	t1, (s0)
107    PTR_ADDU	s0, GOTENT_SZ
1089:  SUBU	s1, 1
109    bgez	s1, 1b
110
111    /* call linker_init */
112    move	a0, sp
113#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
114    PTR_SUBU	sp, 4*REGSZ       /* space for arg saves in linker_init */
115#endif
116    jal		__linker_init
117#if (_MIPS_SIM == _ABIO32) || (_MIPS_SIM == _ABI32)
118    PTR_ADDU	sp, 4*REGSZ        /* restore sp */
119#endif
120    move	t9, v0
121    j		t9
122    .end    __start
123
124/* FIXME:Is this still needed? */
125    .section .ctors, "wa"
126    .globl __CTOR_LIST__
127__CTOR_LIST__:
128    .long -1
129