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 */
32static 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
43static 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
53extern void crc32c_sparc64(u32 *crcp, const u64 *data, unsigned int len);
54
55static 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
77static 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
86static 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
93static 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
99static 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
107static 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
114static 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
126static 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
147static 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
161static 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
171static void __exit crc32c_sparc64_mod_fini(void)
172{
173	crypto_unregister_shash(&alg);
174}
175
176module_init(crc32c_sparc64_mod_init);
177module_exit(crc32c_sparc64_mod_fini);
178
179MODULE_LICENSE("GPL");
180MODULE_DESCRIPTION("CRC32c (Castagnoli), sparc64 crc32c opcode accelerated");
181
182MODULE_ALIAS_CRYPTO("crc32c");
183
184#include "crop_devid.c"
185