1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Accelerated CRC-T10DIF using arm64 NEON and Crypto Extensions instructions
4 *
5 * Copyright (C) 2016 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
6 */
7
8 #include <linux/cpufeature.h>
9 #include <linux/crc-t10dif.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/string.h>
14
15 #include <crypto/internal/simd.h>
16
17 #include <asm/neon.h>
18 #include <asm/simd.h>
19
20 static DEFINE_STATIC_KEY_FALSE(have_asimd);
21 static DEFINE_STATIC_KEY_FALSE(have_pmull);
22
23 #define CRC_T10DIF_PMULL_CHUNK_SIZE 16U
24
25 asmlinkage void crc_t10dif_pmull_p8(u16 init_crc, const u8 *buf, size_t len,
26 u8 out[16]);
27 asmlinkage u16 crc_t10dif_pmull_p64(u16 init_crc, const u8 *buf, size_t len);
28
crc_t10dif_arch(u16 crc,const u8 * data,size_t length)29 u16 crc_t10dif_arch(u16 crc, const u8 *data, size_t length)
30 {
31 if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE) {
32 if (static_branch_likely(&have_pmull)) {
33 if (crypto_simd_usable()) {
34 kernel_neon_begin();
35 crc = crc_t10dif_pmull_p64(crc, data, length);
36 kernel_neon_end();
37 return crc;
38 }
39 } else if (length > CRC_T10DIF_PMULL_CHUNK_SIZE &&
40 static_branch_likely(&have_asimd) &&
41 crypto_simd_usable()) {
42 u8 buf[16];
43
44 kernel_neon_begin();
45 crc_t10dif_pmull_p8(crc, data, length, buf);
46 kernel_neon_end();
47
48 return crc_t10dif_generic(0, buf, sizeof(buf));
49 }
50 }
51 return crc_t10dif_generic(crc, data, length);
52 }
53 EXPORT_SYMBOL(crc_t10dif_arch);
54
crc_t10dif_arm64_init(void)55 static int __init crc_t10dif_arm64_init(void)
56 {
57 if (cpu_have_named_feature(ASIMD)) {
58 static_branch_enable(&have_asimd);
59 if (cpu_have_named_feature(PMULL))
60 static_branch_enable(&have_pmull);
61 }
62 return 0;
63 }
64 arch_initcall(crc_t10dif_arm64_init);
65
crc_t10dif_arm64_exit(void)66 static void __exit crc_t10dif_arm64_exit(void)
67 {
68 }
69 module_exit(crc_t10dif_arm64_exit);
70
71 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
72 MODULE_DESCRIPTION("CRC-T10DIF using arm64 NEON and Crypto Extensions");
73 MODULE_LICENSE("GPL v2");
74