arch/sparc/crypto/crc32c_glue.c

   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_flags              =       CRYPTO_ALG_OPTIONAL_KEY,
 137                 .cra_blocksize          =       CHKSUM_BLOCK_SIZE,
 138                 .cra_ctxsize            =       sizeof(u32),
 139                 .cra_alignmask          =       7,
 140                 .cra_module             =       THIS_MODULE,
 141                 .cra_init               =       crc32c_sparc64_cra_init,
 142         }
 143 };
 144
 145 static bool __init sparc64_has_crc32c_opcode(void)
 146 {
 147         unsigned long cfr;
 148
 149         if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
 150                 return false;
 151
 152         __asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
 153         if (!(cfr & CFR_CRC32C))
 154                 return false;
 155
 156         return true;
 157 }
 158
 159 static int __init crc32c_sparc64_mod_init(void)
 160 {
 161         if (sparc64_has_crc32c_opcode()) {
 162                 pr_info("Using sparc64 crc32c opcode optimized CRC32C implementation\n");
 163                 return crypto_register_shash(&alg);
 164         }
 165         pr_info("sparc64 crc32c opcode not available.\n");
 166         return -ENODEV;
 167 }
 168
 169 static void __exit crc32c_sparc64_mod_fini(void)
 170 {
 171         crypto_unregister_shash(&alg);
 172 }
 173
 174 module_init(crc32c_sparc64_mod_init);
 175 module_exit(crc32c_sparc64_mod_fini);
 176
 177 MODULE_LICENSE("GPL");
 178 MODULE_DESCRIPTION("CRC32c (Castagnoli), sparc64 crc32c opcode accelerated");
 179
 180 MODULE_ALIAS_CRYPTO("crc32c");
 181
 182 #include "crop_devid.c"