/* Startup code for SH & ELF. Copyright (C) 1999 Free Software Foundation, Inc. Copyright (C) 2001 Hewlett-Packard Australia This program is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Derived in part from the Linux-8086 C library, the GNU C Library, and several other sundry sources. Files within this library are copyright by their respective copyright holders. */ /* This is the canonical entry point, usually the first thing in the text segment. At this entry point, most registers' values are unspecified, except: r4 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. WARNING: At that stage only static linker is supported. For uCLinux we won't bother with r4. sp The stack contains the arguments and environment: 0(sp) argc 4(sp) argv[0] ... (4*argc)(sp) NULL (4*(argc+1))(sp) envp[0] ... NULL */ .text .globl _start _start: /* Clear the frame pointer since this is the outermost frame. */ mov #0, r14 /* Pop argc off the stack and save a pointer to argv */ mov.l @r15+,r4 mov r15, r5 /* set up the value for the environment pointer r6 = (argc+1)*4+argv */ mov r4,r6 add #1,r6 shll2 r6 add r5,r6 ! Clear BSS area mov.l 3f, r1 add #4, r1 mov.l 4f, r2 mov #0, r0 9: cmp/hs r2, r1 bf/s 9b ! while (r1 < r2) mov.l r0,@-r2 /* call main */ mov.l L_main,r1 jsr @r1 nop /* should never get here....*/ mov.l L_abort,r1 jsr @r1 nop .align 2 3: .long __bss_start 4: .long _end L_main: .long __uClibc_main L_abort: .long abort .data