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 */
 31static 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
 42static 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
 52extern void crc32c_sparc64(u32 *crcp, const u64 *data, unsigned int len);
 53
 54static 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
 68static 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
 78static 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
 89static 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
 95static 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
103static 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
110static 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
122static 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
144static 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
158static 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
168static void __exit crc32c_sparc64_mod_fini(void)
169{
170	crypto_unregister_shash(&alg);
171}
172
173module_init(crc32c_sparc64_mod_init);
174module_exit(crc32c_sparc64_mod_fini);
175
176MODULE_LICENSE("GPL");
177MODULE_DESCRIPTION("CRC32c (Castagnoli), sparc64 crc32c opcode accelerated");
178
179MODULE_ALIAS_CRYPTO("crc32c");
180
181#include "crop_devid.c"