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/* vi: set sw=4 ts=4: */
/*
* Architecture specific code used by dl-startup.c
* Copyright (C) 2000-2004 by Erik Andersen <andersen@codepoet.org>
*/
asm(
" .text\n"
" .globl _start\n"
" .type _start,%function\n"
"_start:\n"
" @ at start time, all the args are on the stack\n"
" mov r0, sp\n"
" bl _dl_start\n"
" @ returns user entry point in r0\n"
" mov r6, r0\n"
" @ we are PIC code, so get global offset table\n"
" ldr sl, .L_GET_GOT\n"
" add sl, pc, sl\n"
".L_GOT_GOT:\n"
" @ See if we were run as a command with the executable file\n"
" @ name as an extra leading argument.\n"
" ldr r4, .L_SKIP_ARGS\n"
" ldr r4, [sl, r4]\n"
" @ get the original arg count\n"
" ldr r1, [sp]\n"
" @ subtract _dl_skip_args from it\n"
" sub r1, r1, r4\n"
" @ adjust the stack pointer to skip them\n"
" add sp, sp, r4, lsl #2\n"
" @ get the argv address\n"
" add r2, sp, #4\n"
" @ store the new argc in the new stack location\n"
" str r1, [sp]\n"
" @ compute envp\n"
" add r3, r2, r1, lsl #2\n"
" add r3, r3, #4\n"
"\n\n"
" @ load the finalizer function\n"
" ldr r0, .L_FINI_PROC\n"
" ldr r0, [sl, r0]\n"
" @ jump to the user_s entry point\n"
" mov pc, r6\n"
".L_GET_GOT:\n"
" .word _GLOBAL_OFFSET_TABLE_ - .L_GOT_GOT - 4\n"
".L_SKIP_ARGS:\n"
" .word _dl_skip_args(GOTOFF)\n"
".L_FINI_PROC:\n"
" .word _dl_fini(GOT)\n"
"\n\n"
" .size _start,.-_start\n"
".previous\n"
);
/* Get a pointer to the argv array. On many platforms this can be just
* the address if the first argument, on other platforms we need to
* do something a little more subtle here. */
#define GET_ARGV(ARGVP, ARGS) ARGVP = (((unsigned long*)ARGS)+1)
/* Handle relocation of the symbols in the dynamic loader. */
static inline
void PERFORM_BOOTSTRAP_RELOC(ELF_RELOC *rpnt, unsigned long *reloc_addr,
unsigned long symbol_addr, unsigned long load_addr, Elf32_Sym *symtab)
{
switch (ELF32_R_TYPE(rpnt->r_info)) {
case R_ARM_NONE:
break;
case R_ARM_ABS32:
*reloc_addr += symbol_addr;
break;
case R_ARM_PC24:
{
unsigned long addend;
long newvalue, topbits;
addend = *reloc_addr & 0x00ffffff;
if (addend & 0x00800000) addend |= 0xff000000;
newvalue = symbol_addr - (unsigned long)reloc_addr + (addend << 2);
topbits = newvalue & 0xfe000000;
if (topbits != 0xfe000000 && topbits != 0x00000000)
{
#if 0
// Don't bother with this during ldso initilization...
newvalue = fix_bad_pc24(reloc_addr, symbol_addr)
- (unsigned long)reloc_addr + (addend << 2);
topbits = newvalue & 0xfe000000;
if (unlikely(topbits != 0xfe000000 && topbits != 0x00000000))
{
SEND_STDERR("R_ARM_PC24 relocation out of range\n");
_dl_exit(1);
}
#else
SEND_STDERR("R_ARM_PC24 relocation out of range\n");
_dl_exit(1);
#endif
}
newvalue >>= 2;
symbol_addr = (*reloc_addr & 0xff000000) | (newvalue & 0x00ffffff);
*reloc_addr = symbol_addr;
break;
}
case R_ARM_GLOB_DAT:
case R_ARM_JUMP_SLOT:
*reloc_addr = symbol_addr;
break;
case R_ARM_RELATIVE:
*reloc_addr += load_addr;
break;
case R_ARM_COPY:
break;
default:
SEND_STDERR("Unsupported relocation type\n");
_dl_exit(1);
}
}
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