arch/x86/crypto/crc32-pclmul

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   1 /* GPL HEADER START
   2  *
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License version 2 for more details (a copy is included
  13  * in the LICENSE file that accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * version 2 along with this program; If not, see http://www.gnu.org/licenses
  17  *
  18  * Please  visit http://www.xyratex.com/contact if you need additional
  19  * information or have any questions.
  20  *
  21  * GPL HEADER END
  22  */
  23 
  24 /*
  25  * Copyright 2012 Xyratex Technology Limited
  26  *
  27  * Using hardware provided PCLMULQDQ instruction to accelerate the CRC32
  28  * calculation.
  29  * CRC32 polynomial:0x04c11db7(BE)/0xEDB88320(LE)
  30  * PCLMULQDQ is a new instruction in Intel SSE4.2, the reference can be found
  31  * at:
  32  * http://www.intel.com/products/processor/manuals/
  33  * Intel(R) 64 and IA-32 Architectures Software Developer's Manual
  34  * Volume 2B: Instruction Set Reference, N-Z
  35  *
  36  * Authors:   Gregory Prestas <Gregory_Prestas@us.xyratex.com>
  37  *            Alexander Boyko <Alexander_Boyko@xyratex.com>
  38  */
  39 
  40 #include <linux/linkage.h>
  41 #include <asm/inst.h>
  42 
  43 
  44 .section .rodata
  45 .align 16
  46 /*
  47  * [x4*128+32 mod P(x) << 32)]'  << 1   = 0x154442bd4
  48  * #define CONSTANT_R1  0x154442bd4LL
  49  *
  50  * [(x4*128-32 mod P(x) << 32)]' << 1   = 0x1c6e41596
  51  * #define CONSTANT_R2  0x1c6e41596LL
  52  */
  53 .Lconstant_R2R1:
  54         .octa 0x00000001c6e415960000000154442bd4
  55 /*
  56  * [(x128+32 mod P(x) << 32)]'   << 1   = 0x1751997d0
  57  * #define CONSTANT_R3  0x1751997d0LL
  58  *
  59  * [(x128-32 mod P(x) << 32)]'   << 1   = 0x0ccaa009e
  60  * #define CONSTANT_R4  0x0ccaa009eLL
  61  */
  62 .Lconstant_R4R3:
  63         .octa 0x00000000ccaa009e00000001751997d0
  64 /*
  65  * [(x64 mod P(x) << 32)]'       << 1   = 0x163cd6124
  66  * #define CONSTANT_R5  0x163cd6124LL
  67  */
  68 .Lconstant_R5:
  69         .octa 0x00000000000000000000000163cd6124
  70 .Lconstant_mask32:
  71         .octa 0x000000000000000000000000FFFFFFFF
  72 /*
  73  * #define CRCPOLY_TRUE_LE_FULL 0x1DB710641LL
  74  *
  75  * Barrett Reduction constant (u64`) = u` = (x**64 / P(x))` = 0x1F7011641LL
  76  * #define CONSTANT_RU  0x1F7011641LL
  77  */
  78 .Lconstant_RUpoly:
  79         .octa 0x00000001F701164100000001DB710641
  80 
  81 #define CONSTANT %xmm0
  82 
  83 #ifdef __x86_64__
  84 #define BUF     %rdi
  85 #define LEN     %rsi
  86 #define CRC     %edx
  87 #else
  88 #define BUF     %eax
  89 #define LEN     %edx
  90 #define CRC     %ecx
  91 #endif
  92 
  93 
  94 
  95 .text
  96 /**
  97  *      Calculate crc32
  98  *      BUF - buffer (16 bytes aligned)
  99  *      LEN - sizeof buffer (16 bytes aligned), LEN should be grater than 63
 100  *      CRC - initial crc32
 101  *      return %eax crc32
 102  *      uint crc32_pclmul_le_16(unsigned char const *buffer,
 103  *                           size_t len, uint crc32)
 104  */
 105 
 106 ENTRY(crc32_pclmul_le_16) /* buffer and buffer size are 16 bytes aligned */
 107         movdqa  (BUF), %xmm1
 108         movdqa  0x10(BUF), %xmm2
 109         movdqa  0x20(BUF), %xmm3
 110         movdqa  0x30(BUF), %xmm4
 111         movd    CRC, CONSTANT
 112         pxor    CONSTANT, %xmm1
 113         sub     $0x40, LEN
 114         add     $0x40, BUF
 115         cmp     $0x40, LEN
 116         jb      less_64
 117 
 118 #ifdef __x86_64__
 119         movdqa .Lconstant_R2R1(%rip), CONSTANT
 120 #else
 121         movdqa .Lconstant_R2R1, CONSTANT
 122 #endif
 123 
 124 loop_64:/*  64 bytes Full cache line folding */
 125         prefetchnta    0x40(BUF)
 126         movdqa  %xmm1, %xmm5
 127         movdqa  %xmm2, %xmm6
 128         movdqa  %xmm3, %xmm7
 129 #ifdef __x86_64__
 130         movdqa  %xmm4, %xmm8
 131 #endif
 132         PCLMULQDQ 00, CONSTANT, %xmm1
 133         PCLMULQDQ 00, CONSTANT, %xmm2
 134         PCLMULQDQ 00, CONSTANT, %xmm3
 135 #ifdef __x86_64__
 136         PCLMULQDQ 00, CONSTANT, %xmm4
 137 #endif
 138         PCLMULQDQ 0x11, CONSTANT, %xmm5
 139         PCLMULQDQ 0x11, CONSTANT, %xmm6
 140         PCLMULQDQ 0x11, CONSTANT, %xmm7
 141 #ifdef __x86_64__
 142         PCLMULQDQ 0x11, CONSTANT, %xmm8
 143 #endif
 144         pxor    %xmm5, %xmm1
 145         pxor    %xmm6, %xmm2
 146         pxor    %xmm7, %xmm3
 147 #ifdef __x86_64__
 148         pxor    %xmm8, %xmm4
 149 #else
 150         /* xmm8 unsupported for x32 */
 151         movdqa  %xmm4, %xmm5
 152         PCLMULQDQ 00, CONSTANT, %xmm4
 153         PCLMULQDQ 0x11, CONSTANT, %xmm5
 154         pxor    %xmm5, %xmm4
 155 #endif
 156 
 157         pxor    (BUF), %xmm1
 158         pxor    0x10(BUF), %xmm2
 159         pxor    0x20(BUF), %xmm3
 160         pxor    0x30(BUF), %xmm4
 161 
 162         sub     $0x40, LEN
 163         add     $0x40, BUF
 164         cmp     $0x40, LEN
 165         jge     loop_64
 166 less_64:/*  Folding cache line into 128bit */
 167 #ifdef __x86_64__
 168         movdqa  .Lconstant_R4R3(%rip), CONSTANT
 169 #else
 170         movdqa  .Lconstant_R4R3, CONSTANT
 171 #endif
 172         prefetchnta     (BUF)
 173 
 174         movdqa  %xmm1, %xmm5
 175         PCLMULQDQ 0x00, CONSTANT, %xmm1
 176         PCLMULQDQ 0x11, CONSTANT, %xmm5
 177         pxor    %xmm5, %xmm1
 178         pxor    %xmm2, %xmm1
 179 
 180         movdqa  %xmm1, %xmm5
 181         PCLMULQDQ 0x00, CONSTANT, %xmm1
 182         PCLMULQDQ 0x11, CONSTANT, %xmm5
 183         pxor    %xmm5, %xmm1
 184         pxor    %xmm3, %xmm1
 185 
 186         movdqa  %xmm1, %xmm5
 187         PCLMULQDQ 0x00, CONSTANT, %xmm1
 188         PCLMULQDQ 0x11, CONSTANT, %xmm5
 189         pxor    %xmm5, %xmm1
 190         pxor    %xmm4, %xmm1
 191 
 192         cmp     $0x10, LEN
 193         jb      fold_64
 194 loop_16:/* Folding rest buffer into 128bit */
 195         movdqa  %xmm1, %xmm5
 196         PCLMULQDQ 0x00, CONSTANT, %xmm1
 197         PCLMULQDQ 0x11, CONSTANT, %xmm5
 198         pxor    %xmm5, %xmm1
 199         pxor    (BUF), %xmm1
 200         sub     $0x10, LEN
 201         add     $0x10, BUF
 202         cmp     $0x10, LEN
 203         jge     loop_16
 204 
 205 fold_64:
 206         /* perform the last 64 bit fold, also adds 32 zeroes
 207          * to the input stream */
 208         PCLMULQDQ 0x01, %xmm1, CONSTANT /* R4 * xmm1.low */
 209         psrldq  $0x08, %xmm1
 210         pxor    CONSTANT, %xmm1
 211 
 212         /* final 32-bit fold */
 213         movdqa  %xmm1, %xmm2
 214 #ifdef __x86_64__
 215         movdqa  .Lconstant_R5(%rip), CONSTANT
 216         movdqa  .Lconstant_mask32(%rip), %xmm3
 217 #else
 218         movdqa  .Lconstant_R5, CONSTANT
 219         movdqa  .Lconstant_mask32, %xmm3
 220 #endif
 221         psrldq  $0x04, %xmm2
 222         pand    %xmm3, %xmm1
 223         PCLMULQDQ 0x00, CONSTANT, %xmm1
 224         pxor    %xmm2, %xmm1
 225 
 226         /* Finish up with the bit-reversed barrett reduction 64 ==> 32 bits */
 227 #ifdef __x86_64__
 228         movdqa  .Lconstant_RUpoly(%rip), CONSTANT
 229 #else
 230         movdqa  .Lconstant_RUpoly, CONSTANT
 231 #endif
 232         movdqa  %xmm1, %xmm2
 233         pand    %xmm3, %xmm1
 234         PCLMULQDQ 0x10, CONSTANT, %xmm1
 235         pand    %xmm3, %xmm1
 236         PCLMULQDQ 0x00, CONSTANT, %xmm1
 237         pxor    %xmm2, %xmm1
 238         PEXTRD  0x01, %xmm1, %eax
 239 
 240         ret
 241 ENDPROC(crc32_pclmul_le_16)
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root/arch/x86/crypto/crc32-pclmul_asm.S
