/* $NetBSD: rtld_start.S,v 1.1 2014/09/03 19:34:26 matt Exp $ */
/*-
* Copyright (c) 2014 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Matt Thomas of 3am Software Foundry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <machine/asm.h>
.globl _rtld_start
.globl _rtld
#define CF_LEN (3*__SIZEOF_POINTER__)
#define CF_OBJ (2*__SIZEOF_POINTER__)
#define CF_CLEANUP (1*__SIZEOF_POINTER__)
/*
* void ___start(void (*cleanup)(void), const Obj_Entry *obj,
* struct ps_strings *ps_strings);
*/
ENTRY_NP(_rtld_start)
l.sw CF_LEN(r1), r1 # reserve some stack space
#if 0
l.ori r26, r3, 0 # obj (should be 0)
l.ori r28, r4, 0 # cleanup (should be 0)
#endif
l.ori r30, r5, 0 # ps_strings
l.addi r1, r1, -CF_LEN
PIC_GOTSETUP(r16)
l.movhi r3, gotoffhi(_DYNAMIC) # get _DYNAMIC gotoff address
l.ori r3, r3, gotofflo(_DYNAMIC)
l.lwz r7, 0(r16) # get base-relative &_DYNAMIC
l.add r3, r3, r16 # r3 = _DYNAMIC actual address
l.sub r24, r3, r7 # r24 = relocbase
l.ori r4, r24, 0 # r4 = relocbase
l.jal _C_LABEL(_rtld_relocate_nonplt_self)
l.nop
l.addi r3, r1, CF_CLEANUP
l.ori r4, r24, 0 # r4 = relocbase
l.jal _C_LABEL(_rtld) # _start = _rtld(sp, relocbase)
l.nop
l.lwz r3, CF_OBJ(r1) # obj
l.lwz r4, CF_CLEANUP(r1) # cleanup
l.ori r5, r30, 0 # ps_strings
l.addi r1, r1, CF_LEN # pop stack
l.jalr r11 # _start(obj, cleanup, ps_strings)
l.ori r13, r0, 1 # _exit()
l.sys 0
END(_rtld_start)
.globl _rtld_bind
/*
* r11 = rela offset
* r12 = GOT[1] (&obj)
* r15 = GOT[2] (&_rtld_bind_start)
*/
ENTRY_NP(_rtld_bind_start)
l.sw -4(r1), r9 # save lr
l.sw -8(r1), r8 # save arg5
l.sw -12(r1), r7 # save arg4
l.sw -16(r1), r6 # save arg3
l.sw -20(r1), r5 # save arg2
l.sw -24(r1), r4 # save arg1
l.sw -28(r1), r3 # save arg0
l.sw -32(r1), r1 # establish stack frame
l.addi r1, r1, -32
l.ori r3, r12, 0 # obj
l.ori r4, r11, 0 # reloff
l.jal _C_LABEL(_rtld_bind) # _rtld_bind(obj, reloff)
l.nop
l.addi r1, r1, 32 # pop stack frame
l.lwz r3, -28(r1) # restore arg0
l.lwz r4, -24(r1) # restore arg1
l.lwz r5, -20(r1) # restore arg2
l.lwz r6, -16(r1) # restore arg3
l.lwz r7, -12(r1) # restore arg4
l.lwz r8, -8(r1) # restore arg5
l.lwz r9, -4(r1) # restore lr
l.jr r11 # jump to routine
l.nop
END(_rtld_bind_start)