1/*- 2 * Copyright (c) 2016 Stanislav Galabov 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <machine/asm.h> 28 29 .text 30 .extern _C_LABEL(main) 31 .weak _DYNAMIC 32 33/* 34 * Entry point to the loader that U-Boot passes control to. 35 */ 36ENTRY(_start) 37 PTR_S sp, uboot_address 38 j main 39 nop 40END(_start) 41 42/* 43 * syscall() 44 */ 45ENTRY(syscall) 46 PTR_S ra, ret_address 47 PTR_L t9, syscall_ptr 48 jalr t9 49 nop 50 PTR_L ra, ret_address 51 jr ra 52 nop 53END(syscall) 54 55/* 56 * Data section 57 */ 58 .data 59 .align 8 60 .globl syscall_ptr 61syscall_ptr: 62 .dword 0 63 64 .globl uboot_address 65uboot_address: 66 .dword 0 67 68ret_address: 69 .dword 0 70