1/* $NetBSD: rtld_start.S,v 1.9 2008/04/28 20:23:03 martin Exp $ */ 2 3/*- 4 * Copyright (c) 1998, 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matt Thomas and by Charles M. Hannum. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include <machine/asm.h> 33 34 .text 35 .align 0 36 .globl _rtld_start 37 .type _rtld_start,%function 38_rtld_start: 39 sub sp, sp, #8 /* make room for obj_main & exit proc */ 40 mov r4, r0 /* save ps_strings */ 41 42 ldr sl, .L2 43 ldr r5, .L2+4 44 ldr r0, .L2+8 45.L1: 46 add sl, pc, sl 47 ldr r5, [sl, r5] 48 ldr r0, [sl, r0] 49 50 sub r1, sl, r5 /* relocbase */ 51 add r0, r1, r0 /* &_DYNAMIC */ 52 bl _rtld_relocate_nonplt_self 53 54 sub r1, sl, r5 /* relocbase */ 55 mov r0, sp /* sp */ 56 bl _rtld /* call the shared loader */ 57 mov r3, r0 /* save entry point */ 58 59 ldr r2, [sp, #0] /* r2 = cleanup */ 60 ldr r1, [sp, #4] /* r1 = obj_main */ 61 add sp, sp, #8 /* restore stack */ 62 mov r0, r4 /* restore ps_strings */ 63#ifdef _ARM_ARCH_4T 64 bx r3 /* jump to the entry point */ 65#else 66 mov pc, r3 /* jump to the entry point */ 67#endif 68.L2: 69 .word _GLOBAL_OFFSET_TABLE_ - (.L1+8) 70 .word _GLOBAL_OFFSET_TABLE_(GOT) 71 .word _DYNAMIC(GOT) 72 73 .align 0 74 .globl _rtld_bind_start 75 .type _rtld_bind_start,%function 76/* 77 * stack[0] = RA 78 * ip = &GOT[n+3] 79 * lr = &GOT[2] 80 */ 81_rtld_bind_start: 82 stmdb sp!,{r0-r4,sl,fp} 83 84 sub r1, ip, lr /* r1 = 4 * (n + 1) */ 85 sub r1, r1, #4 /* r1 = 4 * n */ 86 add r1, r1, r1 /* r1 = 8 * n */ 87 88 ldr r0, [lr, #-4] /* get obj ptr from GOT[1] */ 89 mov r4, ip /* save GOT location */ 90 91 bl _rtld_bind /* Call the binder */ 92 93 str r0, [r4] /* save address in GOT */ 94 mov ip, r0 /* save new address */ 95 96 ldmia sp!,{r0-r4,sl,fp,lr} /* restore the stack */ 97#ifdef _ARM_ARCH_4T 98 bx ip /* jump to the new address */ 99#else 100 mov pc, ip /* jump to the new address */ 101#endif 102 103