xref: /linux/lib/crc/arm64/crc-t10dif.h (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
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 
10 #include <asm/simd.h>
11 
12 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_asimd);
13 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_pmull);
14 
15 #define CRC_T10DIF_PMULL_CHUNK_SIZE	16U
16 
17 asmlinkage void crc_t10dif_pmull_p8(u16 init_crc, const u8 *buf, size_t len,
18 				    u8 out[16]);
19 asmlinkage u16 crc_t10dif_pmull_p64(u16 init_crc, const u8 *buf, size_t len);
20 
21 static inline u16 crc_t10dif_arch(u16 crc, const u8 *data, size_t length)
22 {
23 	if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && likely(may_use_simd())) {
24 		if (static_branch_likely(&have_pmull)) {
25 			scoped_ksimd()
26 				return crc_t10dif_pmull_p64(crc, data, length);
27 		} else if (length > CRC_T10DIF_PMULL_CHUNK_SIZE &&
28 			   static_branch_likely(&have_asimd)) {
29 			u8 buf[16];
30 
31 			scoped_ksimd()
32 				crc_t10dif_pmull_p8(crc, data, length, buf);
33 
34 			return crc_t10dif_generic(0, buf, sizeof(buf));
35 		}
36 	}
37 	return crc_t10dif_generic(crc, data, length);
38 }
39 
40 #define crc_t10dif_mod_init_arch crc_t10dif_mod_init_arch
41 static void crc_t10dif_mod_init_arch(void)
42 {
43 	if (cpu_have_named_feature(ASIMD)) {
44 		static_branch_enable(&have_asimd);
45 		if (cpu_have_named_feature(PMULL))
46 			static_branch_enable(&have_pmull);
47 	}
48 }
49