xref: /linux/arch/sparc/crypto/crc32c_glue.c (revision 4b911a9690d72641879ea6d13cce1de31d346d79)
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 #include <asm/unaligned.h>
24 
25 #include "opcodes.h"
26 
27 /*
28  * Setting the seed allows arbitrary accumulators and flexible XOR policy
29  * If your algorithm starts with ~0, then XOR with ~0 before you set
30  * the seed.
31  */
32 static int crc32c_sparc64_setkey(struct crypto_shash *hash, const u8 *key,
33 				 unsigned int keylen)
34 {
35 	u32 *mctx = crypto_shash_ctx(hash);
36 
37 	if (keylen != sizeof(u32))
38 		return -EINVAL;
39 	*mctx = get_unaligned_le32(key);
40 	return 0;
41 }
42 
43 static int crc32c_sparc64_init(struct shash_desc *desc)
44 {
45 	u32 *mctx = crypto_shash_ctx(desc->tfm);
46 	u32 *crcp = shash_desc_ctx(desc);
47 
48 	*crcp = *mctx;
49 
50 	return 0;
51 }
52 
53 extern void crc32c_sparc64(u32 *crcp, const u64 *data, unsigned int len);
54 
55 static u32 crc32c_compute(u32 crc, const u8 *data, unsigned int len)
56 {
57 	unsigned int n = -(uintptr_t)data & 7;
58 
59 	if (n) {
60 		/* Data isn't 8-byte aligned.  Align it. */
61 		n = min(n, len);
62 		crc = __crc32c_le(crc, data, n);
63 		data += n;
64 		len -= n;
65 	}
66 	n = len & ~7U;
67 	if (n) {
68 		crc32c_sparc64(&crc, (const u64 *)data, n);
69 		data += n;
70 		len -= n;
71 	}
72 	if (len)
73 		crc = __crc32c_le(crc, data, len);
74 	return crc;
75 }
76 
77 static int crc32c_sparc64_update(struct shash_desc *desc, const u8 *data,
78 				 unsigned int len)
79 {
80 	u32 *crcp = shash_desc_ctx(desc);
81 
82 	*crcp = crc32c_compute(*crcp, data, len);
83 	return 0;
84 }
85 
86 static int __crc32c_sparc64_finup(const u32 *crcp, const u8 *data,
87 				  unsigned int len, u8 *out)
88 {
89 	put_unaligned_le32(~crc32c_compute(*crcp, data, len), out);
90 	return 0;
91 }
92 
93 static int crc32c_sparc64_finup(struct shash_desc *desc, const u8 *data,
94 				unsigned int len, u8 *out)
95 {
96 	return __crc32c_sparc64_finup(shash_desc_ctx(desc), data, len, out);
97 }
98 
99 static int crc32c_sparc64_final(struct shash_desc *desc, u8 *out)
100 {
101 	u32 *crcp = shash_desc_ctx(desc);
102 
103 	put_unaligned_le32(~*crcp, out);
104 	return 0;
105 }
106 
107 static int crc32c_sparc64_digest(struct shash_desc *desc, const u8 *data,
108 				 unsigned int len, u8 *out)
109 {
110 	return __crc32c_sparc64_finup(crypto_shash_ctx(desc->tfm), data, len,
111 				      out);
112 }
113 
114 static int crc32c_sparc64_cra_init(struct crypto_tfm *tfm)
115 {
116 	u32 *key = crypto_tfm_ctx(tfm);
117 
118 	*key = ~0;
119 
120 	return 0;
121 }
122 
123 #define CHKSUM_BLOCK_SIZE	1
124 #define CHKSUM_DIGEST_SIZE	4
125 
126 static struct shash_alg alg = {
127 	.setkey			=	crc32c_sparc64_setkey,
128 	.init			=	crc32c_sparc64_init,
129 	.update			=	crc32c_sparc64_update,
130 	.final			=	crc32c_sparc64_final,
131 	.finup			=	crc32c_sparc64_finup,
132 	.digest			=	crc32c_sparc64_digest,
133 	.descsize		=	sizeof(u32),
134 	.digestsize		=	CHKSUM_DIGEST_SIZE,
135 	.base			=	{
136 		.cra_name		=	"crc32c",
137 		.cra_driver_name	=	"crc32c-sparc64",
138 		.cra_priority		=	SPARC_CR_OPCODE_PRIORITY,
139 		.cra_flags		=	CRYPTO_ALG_OPTIONAL_KEY,
140 		.cra_blocksize		=	CHKSUM_BLOCK_SIZE,
141 		.cra_ctxsize		=	sizeof(u32),
142 		.cra_module		=	THIS_MODULE,
143 		.cra_init		=	crc32c_sparc64_cra_init,
144 	}
145 };
146 
147 static bool __init sparc64_has_crc32c_opcode(void)
148 {
149 	unsigned long cfr;
150 
151 	if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
152 		return false;
153 
154 	__asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
155 	if (!(cfr & CFR_CRC32C))
156 		return false;
157 
158 	return true;
159 }
160 
161 static int __init crc32c_sparc64_mod_init(void)
162 {
163 	if (sparc64_has_crc32c_opcode()) {
164 		pr_info("Using sparc64 crc32c opcode optimized CRC32C implementation\n");
165 		return crypto_register_shash(&alg);
166 	}
167 	pr_info("sparc64 crc32c opcode not available.\n");
168 	return -ENODEV;
169 }
170 
171 static void __exit crc32c_sparc64_mod_fini(void)
172 {
173 	crypto_unregister_shash(&alg);
174 }
175 
176 module_init(crc32c_sparc64_mod_init);
177 module_exit(crc32c_sparc64_mod_fini);
178 
179 MODULE_LICENSE("GPL");
180 MODULE_DESCRIPTION("CRC32c (Castagnoli), sparc64 crc32c opcode accelerated");
181 
182 MODULE_ALIAS_CRYPTO("crc32c");
183 
184 #include "crop_devid.c"
185