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-rw-r--r--arch/x86/crypto/crc32-pclmul_asm.S247
1 files changed, 247 insertions, 0 deletions
diff --git a/arch/x86/crypto/crc32-pclmul_asm.S b/arch/x86/crypto/crc32-pclmul_asm.S
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+/* 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>
+
+
+.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
+#warning Using 32bit code support
+#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)
+ */
+.globl crc32_pclmul_le_16
+.align 4, 0x90
+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
+#ifndef __x86_64__
+ /* This is for position independent code(-fPIC) support for 32bit */
+ call delta
+delta:
+ pop %ecx
+#endif
+ cmp $0x40, LEN
+ jb less_64
+
+#ifdef __x86_64__
+ movdqa .Lconstant_R2R1(%rip), CONSTANT
+#else
+ movdqa .Lconstant_R2R1 - delta(%ecx), 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 - delta(%ecx), 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 - delta(%ecx), CONSTANT
+ movdqa .Lconstant_mask32 - delta(%ecx), %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 - delta(%ecx), 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