/* * Copyright (C) 2004-2007 Atmel Corporation * * This file is subject to the terms and conditions of the GNU Lesser General * Public License. See the file "COPYING.LIB" in the main directory of this * archive for more details. * * When we enter _start, the stack looks like this: * argc argument counter * argv[0] pointer to program name * argv[1..argc-1] pointers to program args * NULL * env[0..N] pointers to environment variables * NULL * * r12 contains a function pointer to be registered with `atexit'. * This is how the dynamic linker arranges to have DT_FINI functions * called for shared libraries that have been loaded before this * code runs. * * We're going to call the following function: * __uClibc_main(int (*main)(int, char **, char **), int argc, * char **argv, void (*app_init)(void), void (*app_fini)(void), * void (*rtld_fini)(void), void *stack_end) * * So we need to set up things as follows: * r12 = address of main * r11 = argc * r10 = &argv[0] * r9 = address of _init * r8 = address of _fini * sp[0] = whatever we got passed in r12 */ #include <features.h> .text .global _start .type _start, @function _start: /* Clear the frame pointer and link register since this is the outermost frame. */ mov r7, 0 mov lr, 0 ld.w r11, sp++ /* argc */ mov r10, sp /* &argv[0] */ st.w --sp, r10 /* stack_end */ st.w --sp, r12 /* rtld_fini */ #ifdef __PIC__ lddpc r6, .L_GOT .L_RGOT: rsub r6, pc lda.w r9, _init lda.w r8, _fini lda.w r12, main /* Ok, now run uClibc's main() -- should not return */ call __uClibc_main .align 2 .L_GOT: .long .L_RGOT - _GLOBAL_OFFSET_TABLE_ #else lddpc r9, __init_addr /* app_init */ lddpc r8, __fini_addr /* app_fini */ lddpc r12, __main_addr /* main */ /* Ok, now run uClibc's main() -- should not return */ lddpc pc, ___uClibc_main_addr .align 2 __init_addr: .long _init __fini_addr: .long _fini __main_addr: .long main ___uClibc_main_addr: .long __uClibc_main #endif .size _start, . - _start /* * The LSB says we need this. */ .section ".note.ABI-tag", "a" .align 4 .long 2f - 1f /* namesz */ .long 4f - 3f /* descsz */ .long 1 /* type */ 1: .asciz "GNU" /* name */ 2: .align 4 3: .long 0 /* Linux executable */ .long 2,6,0 /* Earliest compatible kernel */ 4: .align 4