xref: /openbmc/linux/arch/sparc/crypto/crc32c_glue.c (revision da1d9caf)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Glue code for CRC32C optimized for sparc64 crypto opcodes.
3  *
4  * This is based largely upon arch/x86/crypto/crc32c-intel.c
5  *
6  * Copyright (C) 2008 Intel Corporation
7  * Authors: Austin Zhang <austin_zhang@linux.intel.com>
8  *          Kent Liu <kent.liu@intel.com>
9  */
10 
11 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
12 
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include <linux/kernel.h>
17 #include <linux/crc32.h>
18 
19 #include <crypto/internal/hash.h>
20 
21 #include <asm/pstate.h>
22 #include <asm/elf.h>
23 
24 #include "opcodes.h"
25 
26 /*
27  * Setting the seed allows arbitrary accumulators and flexible XOR policy
28  * If your algorithm starts with ~0, then XOR with ~0 before you set
29  * the seed.
30  */
31 static int crc32c_sparc64_setkey(struct crypto_shash *hash, const u8 *key,
32 				 unsigned int keylen)
33 {
34 	u32 *mctx = crypto_shash_ctx(hash);
35 
36 	if (keylen != sizeof(u32))
37 		return -EINVAL;
38 	*mctx = le32_to_cpup((__le32 *)key);
39 	return 0;
40 }
41 
42 static int crc32c_sparc64_init(struct shash_desc *desc)
43 {
44 	u32 *mctx = crypto_shash_ctx(desc->tfm);
45 	u32 *crcp = shash_desc_ctx(desc);
46 
47 	*crcp = *mctx;
48 
49 	return 0;
50 }
51 
52 extern void crc32c_sparc64(u32 *crcp, const u64 *data, unsigned int len);
53 
54 static void crc32c_compute(u32 *crcp, const u64 *data, unsigned int len)
55 {
56 	unsigned int asm_len;
57 
58 	asm_len = len & ~7U;
59 	if (asm_len) {
60 		crc32c_sparc64(crcp, data, asm_len);
61 		data += asm_len / 8;
62 		len -= asm_len;
63 	}
64 	if (len)
65 		*crcp = __crc32c_le(*crcp, (const unsigned char *) data, len);
66 }
67 
68 static int crc32c_sparc64_update(struct shash_desc *desc, const u8 *data,
69 				 unsigned int len)
70 {
71 	u32 *crcp = shash_desc_ctx(desc);
72 
73 	crc32c_compute(crcp, (const u64 *) data, len);
74 
75 	return 0;
76 }
77 
78 static int __crc32c_sparc64_finup(u32 *crcp, const u8 *data, unsigned int len,
79 				  u8 *out)
80 {
81 	u32 tmp = *crcp;
82 
83 	crc32c_compute(&tmp, (const u64 *) data, len);
84 
85 	*(__le32 *) out = ~cpu_to_le32(tmp);
86 	return 0;
87 }
88 
89 static int crc32c_sparc64_finup(struct shash_desc *desc, const u8 *data,
90 				unsigned int len, u8 *out)
91 {
92 	return __crc32c_sparc64_finup(shash_desc_ctx(desc), data, len, out);
93 }
94 
95 static int crc32c_sparc64_final(struct shash_desc *desc, u8 *out)
96 {
97 	u32 *crcp = shash_desc_ctx(desc);
98 
99 	*(__le32 *) out = ~cpu_to_le32p(crcp);
100 	return 0;
101 }
102 
103 static int crc32c_sparc64_digest(struct shash_desc *desc, const u8 *data,
104 				 unsigned int len, u8 *out)
105 {
106 	return __crc32c_sparc64_finup(crypto_shash_ctx(desc->tfm), data, len,
107 				      out);
108 }
109 
110 static int crc32c_sparc64_cra_init(struct crypto_tfm *tfm)
111 {
112 	u32 *key = crypto_tfm_ctx(tfm);
113 
114 	*key = ~0;
115 
116 	return 0;
117 }
118 
119 #define CHKSUM_BLOCK_SIZE	1
120 #define CHKSUM_DIGEST_SIZE	4
121 
122 static struct shash_alg alg = {
123 	.setkey			=	crc32c_sparc64_setkey,
124 	.init			=	crc32c_sparc64_init,
125 	.update			=	crc32c_sparc64_update,
126 	.final			=	crc32c_sparc64_final,
127 	.finup			=	crc32c_sparc64_finup,
128 	.digest			=	crc32c_sparc64_digest,
129 	.descsize		=	sizeof(u32),
130 	.digestsize		=	CHKSUM_DIGEST_SIZE,
131 	.base			=	{
132 		.cra_name		=	"crc32c",
133 		.cra_driver_name	=	"crc32c-sparc64",
134 		.cra_priority		=	SPARC_CR_OPCODE_PRIORITY,
135 		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
136 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
137 		.cra_ctxsize		=	sizeof(u32),
138 		.cra_alignmask		=	7,
139 		.cra_module		=	THIS_MODULE,
140 		.cra_init		=	crc32c_sparc64_cra_init,
141 	}
142 };
143 
144 static bool __init sparc64_has_crc32c_opcode(void)
145 {
146 	unsigned long cfr;
147 
148 	if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
149 		return false;
150 
151 	__asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
152 	if (!(cfr & CFR_CRC32C))
153 		return false;
154 
155 	return true;
156 }
157 
158 static int __init crc32c_sparc64_mod_init(void)
159 {
160 	if (sparc64_has_crc32c_opcode()) {
161 		pr_info("Using sparc64 crc32c opcode optimized CRC32C implementation\n");
162 		return crypto_register_shash(&alg);
163 	}
164 	pr_info("sparc64 crc32c opcode not available.\n");
165 	return -ENODEV;
166 }
167 
168 static void __exit crc32c_sparc64_mod_fini(void)
169 {
170 	crypto_unregister_shash(&alg);
171 }
172 
173 module_init(crc32c_sparc64_mod_init);
174 module_exit(crc32c_sparc64_mod_fini);
175 
176 MODULE_LICENSE("GPL");
177 MODULE_DESCRIPTION("CRC32c (Castagnoli), sparc64 crc32c opcode accelerated");
178 
179 MODULE_ALIAS_CRYPTO("crc32c");
180 
181 #include "crop_devid.c"
182