xref: /openbmc/linux/arch/sparc/crypto/crc32c_glue.c (revision 94cdda6b)
1 /* Glue code for CRC32C optimized for sparc64 crypto opcodes.
2  *
3  * This is based largely upon arch/x86/crypto/crc32c-intel.c
4  *
5  * Copyright (C) 2008 Intel Corporation
6  * Authors: Austin Zhang <austin_zhang@linux.intel.com>
7  *          Kent Liu <kent.liu@intel.com>
8  */
9 
10 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
11 
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/string.h>
15 #include <linux/kernel.h>
16 #include <linux/crc32.h>
17 
18 #include <crypto/internal/hash.h>
19 
20 #include <asm/pstate.h>
21 #include <asm/elf.h>
22 
23 #include "opcodes.h"
24 
25 /*
26  * Setting the seed allows arbitrary accumulators and flexible XOR policy
27  * If your algorithm starts with ~0, then XOR with ~0 before you set
28  * the seed.
29  */
30 static int crc32c_sparc64_setkey(struct crypto_shash *hash, const u8 *key,
31 				 unsigned int keylen)
32 {
33 	u32 *mctx = crypto_shash_ctx(hash);
34 
35 	if (keylen != sizeof(u32)) {
36 		crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
37 		return -EINVAL;
38 	}
39 	*(__le32 *)mctx = le32_to_cpup((__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 void crc32c_compute(u32 *crcp, const u64 *data, unsigned int len)
56 {
57 	unsigned int asm_len;
58 
59 	asm_len = len & ~7U;
60 	if (asm_len) {
61 		crc32c_sparc64(crcp, data, asm_len);
62 		data += asm_len / 8;
63 		len -= asm_len;
64 	}
65 	if (len)
66 		*crcp = __crc32c_le(*crcp, (const unsigned char *) data, len);
67 }
68 
69 static int crc32c_sparc64_update(struct shash_desc *desc, const u8 *data,
70 				 unsigned int len)
71 {
72 	u32 *crcp = shash_desc_ctx(desc);
73 
74 	crc32c_compute(crcp, (const u64 *) data, len);
75 
76 	return 0;
77 }
78 
79 static int __crc32c_sparc64_finup(u32 *crcp, const u8 *data, unsigned int len,
80 				  u8 *out)
81 {
82 	u32 tmp = *crcp;
83 
84 	crc32c_compute(&tmp, (const u64 *) data, len);
85 
86 	*(__le32 *) out = ~cpu_to_le32(tmp);
87 	return 0;
88 }
89 
90 static int crc32c_sparc64_finup(struct shash_desc *desc, const u8 *data,
91 				unsigned int len, u8 *out)
92 {
93 	return __crc32c_sparc64_finup(shash_desc_ctx(desc), data, len, out);
94 }
95 
96 static int crc32c_sparc64_final(struct shash_desc *desc, u8 *out)
97 {
98 	u32 *crcp = shash_desc_ctx(desc);
99 
100 	*(__le32 *) out = ~cpu_to_le32p(crcp);
101 	return 0;
102 }
103 
104 static int crc32c_sparc64_digest(struct shash_desc *desc, const u8 *data,
105 				 unsigned int len, u8 *out)
106 {
107 	return __crc32c_sparc64_finup(crypto_shash_ctx(desc->tfm), data, len,
108 				      out);
109 }
110 
111 static int crc32c_sparc64_cra_init(struct crypto_tfm *tfm)
112 {
113 	u32 *key = crypto_tfm_ctx(tfm);
114 
115 	*key = ~0;
116 
117 	return 0;
118 }
119 
120 #define CHKSUM_BLOCK_SIZE	1
121 #define CHKSUM_DIGEST_SIZE	4
122 
123 static struct shash_alg alg = {
124 	.setkey			=	crc32c_sparc64_setkey,
125 	.init			=	crc32c_sparc64_init,
126 	.update			=	crc32c_sparc64_update,
127 	.final			=	crc32c_sparc64_final,
128 	.finup			=	crc32c_sparc64_finup,
129 	.digest			=	crc32c_sparc64_digest,
130 	.descsize		=	sizeof(u32),
131 	.digestsize		=	CHKSUM_DIGEST_SIZE,
132 	.base			=	{
133 		.cra_name		=	"crc32c",
134 		.cra_driver_name	=	"crc32c-sparc64",
135 		.cra_priority		=	SPARC_CR_OPCODE_PRIORITY,
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