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__FBSDID("$FreeBSD$"); 30 31.arch_extension crc 32 33/* 34 * uint32_t 35 * armv8_crc32c(uint32_t crc, const unsigned char *buf, unsigned int len) 36 */ 37 38ENTRY(armv8_crc32c) 39 cbz w2, end 40 tbz x1, #0x0, half_word_aligned 41 sub w2, w2, 0x1 42 ldr w10, [x1], #0x1 43 crc32cb w0, w0, w10 44half_word_aligned: 45 cmp w2, #0x2 46 b.lo last_byte 47 tbz x1, #0x1, word_aligned 48 sub w2, w2, 0x2 49 ldr w10, [x1], #0x2 50 crc32ch w0, w0, w10 51word_aligned: 52 cmp w2, #0x4 53 b.lo last_half_word 54 tbz x1, #0x2, double_word_aligned 55 sub w2, w2, 0x4 56 ldr w10, [x1], #0x4 57 crc32cw w0, w0, w10 58double_word_aligned: 59 lsr w9, w2, #0x3 60 cbz w9, last_word 61loop: 62 ldr x10, [x1], #0x8 63 crc32cx w0, w0, x10 64 subs w9, w9, #1 65 b.ne loop 66last_word: 67 tbz w2, #0x2, last_half_word 68 ldr w10, [x1], #0x4 69 crc32cw w0, w0, w10 70last_half_word: 71 tbz w2, #0x1, last_byte 72 ldr w10, [x1], #0x2 73 crc32ch w0, w0, w10 74last_byte: 75 tbz w2, #0x0, end 76 ldr w10, [x1], #0x1 77 crc32cb w0, w0, w10 78end: 79 ret 80END(armv8_crc32c) 81