summaryrefslogtreecommitdiff
path: root/arch/x86/crypto/crc32-pclmul_asm.S
blob: 1c099dc08cc33151ec97c0a250813783c9bf9c4c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
/* GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see http://www.gnu.org/licenses
 *
 * Please  visit http://www.xyratex.com/contact if you need additional
 * information or have any questions.
 *
 * GPL HEADER END
 */

/*
 * Copyright 2012 Xyratex Technology Limited
 *
 * Using hardware provided PCLMULQDQ instruction to accelerate the CRC32
 * calculation.
 * CRC32 polynomial:0x04c11db7(BE)/0xEDB88320(LE)
 * PCLMULQDQ is a new instruction in Intel SSE4.2, the reference can be found
 * at:
 * http://www.intel.com/products/processor/manuals/
 * Intel(R) 64 and IA-32 Architectures Software Developer's Manual
 * Volume 2B: Instruction Set Reference, N-Z
 *
 * Authors:   Gregory Prestas <Gregory_Prestas@us.xyratex.com>
 *	      Alexander Boyko <Alexander_Boyko@xyratex.com>
 */

#include <linux/linkage.h>
#include <asm/inst.h>


.section .rodata
.align 16
/*
 * [x4*128+32 mod P(x) << 32)]'  << 1   = 0x154442bd4
 * #define CONSTANT_R1  0x154442bd4LL
 *
 * [(x4*128-32 mod P(x) << 32)]' << 1   = 0x1c6e41596
 * #define CONSTANT_R2  0x1c6e41596LL
 */
.Lconstant_R2R1:
	.octa 0x00000001c6e415960000000154442bd4
/*
 * [(x128+32 mod P(x) << 32)]'   << 1   = 0x1751997d0
 * #define CONSTANT_R3  0x1751997d0LL
 *
 * [(x128-32 mod P(x) << 32)]'   << 1   = 0x0ccaa009e
 * #define CONSTANT_R4  0x0ccaa009eLL
 */
.Lconstant_R4R3:
	.octa 0x00000000ccaa009e00000001751997d0
/*
 * [(x64 mod P(x) << 32)]'       << 1   = 0x163cd6124
 * #define CONSTANT_R5  0x163cd6124LL
 */
.Lconstant_R5:
	.octa 0x00000000000000000000000163cd6124
.Lconstant_mask32:
	.octa 0x000000000000000000000000FFFFFFFF
/*
 * #define CRCPOLY_TRUE_LE_FULL 0x1DB710641LL
 *
 * Barrett Reduction constant (u64`) = u` = (x**64 / P(x))` = 0x1F7011641LL
 * #define CONSTANT_RU  0x1F7011641LL
 */
.Lconstant_RUpoly:
	.octa 0x00000001F701164100000001DB710641

#define CONSTANT %xmm0

#ifdef __x86_64__
#define BUF     %rdi
#define LEN     %rsi
#define CRC     %edx
#else
#define BUF     %eax
#define LEN     %edx
#define CRC     %ecx
#endif



.text
/**
 *      Calculate crc32
 *      BUF - buffer (16 bytes aligned)
 *      LEN - sizeof buffer (16 bytes aligned), LEN should be grater than 63
 *      CRC - initial crc32
 *      return %eax crc32
 *      uint crc32_pclmul_le_16(unsigned char const *buffer,
 *	                     size_t len, uint crc32)
 */

ENTRY(crc32_pclmul_le_16) /* buffer and buffer size are 16 bytes aligned */
	movdqa  (BUF), %xmm1
	movdqa  0x10(BUF), %xmm2
	movdqa  0x20(BUF), %xmm3
	movdqa  0x30(BUF), %xmm4
	movd    CRC, CONSTANT
	pxor    CONSTANT, %xmm1
	sub     $0x40, LEN
	add     $0x40, BUF
	cmp     $0x40, LEN
	jb      less_64

#ifdef __x86_64__
	movdqa .Lconstant_R2R1(%rip), CONSTANT
#else
	movdqa .Lconstant_R2R1, CONSTANT
#endif

loop_64:/*  64 bytes Full cache line folding */
	prefetchnta    0x40(BUF)
	movdqa  %xmm1, %xmm5
	movdqa  %xmm2, %xmm6
	movdqa  %xmm3, %xmm7
#ifdef __x86_64__
	movdqa  %xmm4, %xmm8
#endif
	PCLMULQDQ 00, CONSTANT, %xmm1
	PCLMULQDQ 00, CONSTANT, %xmm2
	PCLMULQDQ 00, CONSTANT, %xmm3
#ifdef __x86_64__
	PCLMULQDQ 00, CONSTANT, %xmm4
#endif
	PCLMULQDQ 0x11, CONSTANT, %xmm5
	PCLMULQDQ 0x11, CONSTANT, %xmm6
	PCLMULQDQ 0x11, CONSTANT, %xmm7
#ifdef __x86_64__
	PCLMULQDQ 0x11, CONSTANT, %xmm8
#endif
	pxor    %xmm5, %xmm1
	pxor    %xmm6, %xmm2
	pxor    %xmm7, %xmm3
#ifdef __x86_64__
	pxor    %xmm8, %xmm4
#else
	/* xmm8 unsupported for x32 */
	movdqa  %xmm4, %xmm5
	PCLMULQDQ 00, CONSTANT, %xmm4
	PCLMULQDQ 0x11, CONSTANT, %xmm5
	pxor    %xmm5, %xmm4
#endif

	pxor    (BUF), %xmm1
	pxor    0x10(BUF), %xmm2
	pxor    0x20(BUF), %xmm3
	pxor    0x30(BUF), %xmm4

	sub     $0x40, LEN
	add     $0x40, BUF
	cmp     $0x40, LEN
	jge     loop_64
less_64:/*  Folding cache line into 128bit */
#ifdef __x86_64__
	movdqa  .Lconstant_R4R3(%rip), CONSTANT
#else
	movdqa  .Lconstant_R4R3, CONSTANT
#endif
	prefetchnta     (BUF)

	movdqa  %xmm1, %xmm5
	PCLMULQDQ 0x00, CONSTANT, %xmm1
	PCLMULQDQ 0x11, CONSTANT, %xmm5
	pxor    %xmm5, %xmm1
	pxor    %xmm2, %xmm1

	movdqa  %xmm1, %xmm5
	PCLMULQDQ 0x00, CONSTANT, %xmm1
	PCLMULQDQ 0x11, CONSTANT, %xmm5
	pxor    %xmm5, %xmm1
	pxor    %xmm3, %xmm1

	movdqa  %xmm1, %xmm5
	PCLMULQDQ 0x00, CONSTANT, %xmm1
	PCLMULQDQ 0x11, CONSTANT, %xmm5
	pxor    %xmm5, %xmm1
	pxor    %xmm4, %xmm1

	cmp     $0x10, LEN
	jb      fold_64
loop_16:/* Folding rest buffer into 128bit */
	movdqa  %xmm1, %xmm5
	PCLMULQDQ 0x00, CONSTANT, %xmm1
	PCLMULQDQ 0x11, CONSTANT, %xmm5
	pxor    %xmm5, %xmm1
	pxor    (BUF), %xmm1
	sub     $0x10, LEN
	add     $0x10, BUF
	cmp     $0x10, LEN
	jge     loop_16

fold_64:
	/* perform the last 64 bit fold, also adds 32 zeroes
	 * to the input stream */
	PCLMULQDQ 0x01, %xmm1, CONSTANT /* R4 * xmm1.low */
	psrldq  $0x08, %xmm1
	pxor    CONSTANT, %xmm1

	/* final 32-bit fold */
	movdqa  %xmm1, %xmm2
#ifdef __x86_64__
	movdqa  .Lconstant_R5(%rip), CONSTANT
	movdqa  .Lconstant_mask32(%rip), %xmm3
#else
	movdqa  .Lconstant_R5, CONSTANT
	movdqa  .Lconstant_mask32, %xmm3
#endif
	psrldq  $0x04, %xmm2
	pand    %xmm3, %xmm1
	PCLMULQDQ 0x00, CONSTANT, %xmm1
	pxor    %xmm2, %xmm1

	/* Finish up with the bit-reversed barrett reduction 64 ==> 32 bits */
#ifdef __x86_64__
	movdqa  .Lconstant_RUpoly(%rip), CONSTANT
#else
	movdqa  .Lconstant_RUpoly, CONSTANT
#endif
	movdqa  %xmm1, %xmm2
	pand    %xmm3, %xmm1
	PCLMULQDQ 0x10, CONSTANT, %xmm1
	pand    %xmm3, %xmm1
	PCLMULQDQ 0x00, CONSTANT, %xmm1
	pxor    %xmm2, %xmm1
	PEXTRD  0x01, %xmm1, %eax

	ret
ENDPROC(crc32_pclmul_le_16)