1/*- 2 * Copyright (c) 2017 Michael Tuexen 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 28#include <machine/asm.h> 29.arch_extension crc 30 31/* 32 * uint32_t 33 * armv8_crc32c(uint32_t crc, const unsigned char *buf, unsigned int len) 34 */ 35 36ENTRY(armv8_crc32c) 37 cbz w2, end 38 tbz x1, #0x0, half_word_aligned 39 sub w2, w2, 0x1 40 ldr w10, [x1], #0x1 41 crc32cb w0, w0, w10 42half_word_aligned: 43 cmp w2, #0x2 44 b.lo last_byte 45 tbz x1, #0x1, word_aligned 46 sub w2, w2, 0x2 47 ldr w10, [x1], #0x2 48 crc32ch w0, w0, w10 49word_aligned: 50 cmp w2, #0x4 51 b.lo last_half_word 52 tbz x1, #0x2, double_word_aligned 53 sub w2, w2, 0x4 54 ldr w10, [x1], #0x4 55 crc32cw w0, w0, w10 56double_word_aligned: 57 lsr w9, w2, #0x3 58 cbz w9, last_word 59loop: 60 ldr x10, [x1], #0x8 61 crc32cx w0, w0, x10 62 subs w9, w9, #1 63 b.ne loop 64last_word: 65 tbz w2, #0x2, last_half_word 66 ldr w10, [x1], #0x4 67 crc32cw w0, w0, w10 68last_half_word: 69 tbz w2, #0x1, last_byte 70 ldr w10, [x1], #0x2 71 crc32ch w0, w0, w10 72last_byte: 73 tbz w2, #0x0, end 74 ldr w10, [x1], #0x1 75 crc32cb w0, w0, w10 76end: 77 ret 78END(armv8_crc32c) 79