465 lines
13 KiB
ArmAsm
465 lines
13 KiB
ArmAsm
|
/*
|
||
|
* Implement fast CRC32C with PCLMULQDQ instructions. (x86_64)
|
||
|
*
|
||
|
* The white papers on CRC32C calculations with PCLMULQDQ instruction can be
|
||
|
* downloaded from:
|
||
|
* http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/crc-iscsi-polynomial-crc32-instruction-paper.pdf
|
||
|
* http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-paper.pdf
|
||
|
*
|
||
|
* Copyright (C) 2012 Intel Corporation.
|
||
|
*
|
||
|
* Authors:
|
||
|
* Wajdi Feghali <wajdi.k.feghali@intel.com>
|
||
|
* James Guilford <james.guilford@intel.com>
|
||
|
* David Cote <david.m.cote@intel.com>
|
||
|
* Tim Chen <tim.c.chen@linux.intel.com>
|
||
|
*
|
||
|
* This software is available to you under a choice of one of two
|
||
|
* licenses. You may choose to be licensed under the terms of the GNU
|
||
|
* General Public License (GPL) Version 2, available from the file
|
||
|
* COPYING in the main directory of this source tree, or the
|
||
|
* OpenIB.org BSD license below:
|
||
|
*
|
||
|
* Redistribution and use in source and binary forms, with or
|
||
|
* without modification, are permitted provided that the following
|
||
|
* conditions are met:
|
||
|
*
|
||
|
* - Redistributions of source code must retain the above
|
||
|
* copyright notice, this list of conditions and the following
|
||
|
* disclaimer.
|
||
|
*
|
||
|
* - Redistributions in binary form must reproduce the above
|
||
|
* copyright notice, this list of conditions and the following
|
||
|
* disclaimer in the documentation and/or other materials
|
||
|
* provided with the distribution.
|
||
|
*
|
||
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
||
|
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
|
||
|
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
||
|
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
|
||
|
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
|
||
|
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
|
||
|
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
||
|
* SOFTWARE.
|
||
|
*/
|
||
|
|
||
|
#include <asm/inst.h>
|
||
|
#include <linux/linkage.h>
|
||
|
#include <asm/nospec-branch.h>
|
||
|
|
||
|
## ISCSI CRC 32 Implementation with crc32 and pclmulqdq Instruction
|
||
|
|
||
|
.macro LABEL prefix n
|
||
|
\prefix\n\():
|
||
|
.endm
|
||
|
|
||
|
.macro JMPTBL_ENTRY i
|
||
|
.word crc_\i - crc_array
|
||
|
.endm
|
||
|
|
||
|
.macro JNC_LESS_THAN j
|
||
|
jnc less_than_\j
|
||
|
.endm
|
||
|
|
||
|
# Define threshold where buffers are considered "small" and routed to more
|
||
|
# efficient "by-1" code. This "by-1" code only handles up to 255 bytes, so
|
||
|
# SMALL_SIZE can be no larger than 255.
|
||
|
|
||
|
#define SMALL_SIZE 200
|
||
|
|
||
|
.if (SMALL_SIZE > 255)
|
||
|
.error "SMALL_ SIZE must be < 256"
|
||
|
.endif
|
||
|
|
||
|
# unsigned int crc_pcl(u8 *buffer, int len, unsigned int crc_init);
|
||
|
|
||
|
.text
|
||
|
ENTRY(crc_pcl)
|
||
|
#define bufp %rdi
|
||
|
#define bufp_dw %edi
|
||
|
#define bufp_w %di
|
||
|
#define bufp_b %dil
|
||
|
#define bufptmp %rcx
|
||
|
#define block_0 %rcx
|
||
|
#define block_1 %rdx
|
||
|
#define block_2 %r11
|
||
|
#define len %rsi
|
||
|
#define len_dw %esi
|
||
|
#define len_w %si
|
||
|
#define len_b %sil
|
||
|
#define crc_init_arg %rdx
|
||
|
#define tmp %rbx
|
||
|
#define crc_init %r8
|
||
|
#define crc_init_dw %r8d
|
||
|
#define crc1 %r9
|
||
|
#define crc2 %r10
|
||
|
|
||
|
pushq %rbx
|
||
|
pushq %rdi
|
||
|
pushq %rsi
|
||
|
|
||
|
## Move crc_init for Linux to a different
|
||
|
mov crc_init_arg, crc_init
|
||
|
|
||
|
################################################################
|
||
|
## 1) ALIGN:
|
||
|
################################################################
|
||
|
|
||
|
mov bufp, bufptmp # rdi = *buf
|
||
|
neg bufp
|
||
|
and $7, bufp # calculate the unalignment amount of
|
||
|
# the address
|
||
|
je proc_block # Skip if aligned
|
||
|
|
||
|
## If len is less than 8 and we're unaligned, we need to jump
|
||
|
## to special code to avoid reading beyond the end of the buffer
|
||
|
cmp $8, len
|
||
|
jae do_align
|
||
|
# less_than_8 expects length in upper 3 bits of len_dw
|
||
|
# less_than_8_post_shl1 expects length = carryflag * 8 + len_dw[31:30]
|
||
|
shl $32-3+1, len_dw
|
||
|
jmp less_than_8_post_shl1
|
||
|
|
||
|
do_align:
|
||
|
#### Calculate CRC of unaligned bytes of the buffer (if any)
|
||
|
movq (bufptmp), tmp # load a quadward from the buffer
|
||
|
add bufp, bufptmp # align buffer pointer for quadword
|
||
|
# processing
|
||
|
sub bufp, len # update buffer length
|
||
|
align_loop:
|
||
|
crc32b %bl, crc_init_dw # compute crc32 of 1-byte
|
||
|
shr $8, tmp # get next byte
|
||
|
dec bufp
|
||
|
jne align_loop
|
||
|
|
||
|
proc_block:
|
||
|
|
||
|
################################################################
|
||
|
## 2) PROCESS BLOCKS:
|
||
|
################################################################
|
||
|
|
||
|
## compute num of bytes to be processed
|
||
|
movq len, tmp # save num bytes in tmp
|
||
|
|
||
|
cmpq $128*24, len
|
||
|
jae full_block
|
||
|
|
||
|
continue_block:
|
||
|
cmpq $SMALL_SIZE, len
|
||
|
jb small
|
||
|
|
||
|
## len < 128*24
|
||
|
movq $2731, %rax # 2731 = ceil(2^16 / 24)
|
||
|
mul len_dw
|
||
|
shrq $16, %rax
|
||
|
|
||
|
## eax contains floor(bytes / 24) = num 24-byte chunks to do
|
||
|
|
||
|
## process rax 24-byte chunks (128 >= rax >= 0)
|
||
|
|
||
|
## compute end address of each block
|
||
|
## block 0 (base addr + RAX * 8)
|
||
|
## block 1 (base addr + RAX * 16)
|
||
|
## block 2 (base addr + RAX * 24)
|
||
|
lea (bufptmp, %rax, 8), block_0
|
||
|
lea (block_0, %rax, 8), block_1
|
||
|
lea (block_1, %rax, 8), block_2
|
||
|
|
||
|
xor crc1, crc1
|
||
|
xor crc2, crc2
|
||
|
|
||
|
## branch into array
|
||
|
lea jump_table(%rip), bufp
|
||
|
movzxw (bufp, %rax, 2), len
|
||
|
lea crc_array(%rip), bufp
|
||
|
lea (bufp, len, 1), bufp
|
||
|
JMP_NOSPEC bufp
|
||
|
|
||
|
################################################################
|
||
|
## 2a) PROCESS FULL BLOCKS:
|
||
|
################################################################
|
||
|
full_block:
|
||
|
movl $128,%eax
|
||
|
lea 128*8*2(block_0), block_1
|
||
|
lea 128*8*3(block_0), block_2
|
||
|
add $128*8*1, block_0
|
||
|
|
||
|
xor crc1,crc1
|
||
|
xor crc2,crc2
|
||
|
|
||
|
# Fall thruogh into top of crc array (crc_128)
|
||
|
|
||
|
################################################################
|
||
|
## 3) CRC Array:
|
||
|
################################################################
|
||
|
|
||
|
crc_array:
|
||
|
i=128
|
||
|
.rept 128-1
|
||
|
.altmacro
|
||
|
LABEL crc_ %i
|
||
|
.noaltmacro
|
||
|
crc32q -i*8(block_0), crc_init
|
||
|
crc32q -i*8(block_1), crc1
|
||
|
crc32q -i*8(block_2), crc2
|
||
|
i=(i-1)
|
||
|
.endr
|
||
|
|
||
|
.altmacro
|
||
|
LABEL crc_ %i
|
||
|
.noaltmacro
|
||
|
crc32q -i*8(block_0), crc_init
|
||
|
crc32q -i*8(block_1), crc1
|
||
|
# SKIP crc32 -i*8(block_2), crc2 ; Don't do this one yet
|
||
|
|
||
|
mov block_2, block_0
|
||
|
|
||
|
################################################################
|
||
|
## 4) Combine three results:
|
||
|
################################################################
|
||
|
|
||
|
lea (K_table-8)(%rip), bufp # first entry is for idx 1
|
||
|
shlq $3, %rax # rax *= 8
|
||
|
pmovzxdq (bufp,%rax), %xmm0 # 2 consts: K1:K2
|
||
|
leal (%eax,%eax,2), %eax # rax *= 3 (total *24)
|
||
|
subq %rax, tmp # tmp -= rax*24
|
||
|
|
||
|
movq crc_init, %xmm1 # CRC for block 1
|
||
|
PCLMULQDQ 0x00,%xmm0,%xmm1 # Multiply by K2
|
||
|
|
||
|
movq crc1, %xmm2 # CRC for block 2
|
||
|
PCLMULQDQ 0x10, %xmm0, %xmm2 # Multiply by K1
|
||
|
|
||
|
pxor %xmm2,%xmm1
|
||
|
movq %xmm1, %rax
|
||
|
xor -i*8(block_2), %rax
|
||
|
mov crc2, crc_init
|
||
|
crc32 %rax, crc_init
|
||
|
|
||
|
################################################################
|
||
|
## 5) Check for end:
|
||
|
################################################################
|
||
|
|
||
|
LABEL crc_ 0
|
||
|
mov tmp, len
|
||
|
cmp $128*24, tmp
|
||
|
jae full_block
|
||
|
cmp $24, tmp
|
||
|
jae continue_block
|
||
|
|
||
|
less_than_24:
|
||
|
shl $32-4, len_dw # less_than_16 expects length
|
||
|
# in upper 4 bits of len_dw
|
||
|
jnc less_than_16
|
||
|
crc32q (bufptmp), crc_init
|
||
|
crc32q 8(bufptmp), crc_init
|
||
|
jz do_return
|
||
|
add $16, bufptmp
|
||
|
# len is less than 8 if we got here
|
||
|
# less_than_8 expects length in upper 3 bits of len_dw
|
||
|
# less_than_8_post_shl1 expects length = carryflag * 8 + len_dw[31:30]
|
||
|
shl $2, len_dw
|
||
|
jmp less_than_8_post_shl1
|
||
|
|
||
|
#######################################################################
|
||
|
## 6) LESS THAN 256-bytes REMAIN AT THIS POINT (8-bits of len are full)
|
||
|
#######################################################################
|
||
|
small:
|
||
|
shl $32-8, len_dw # Prepare len_dw for less_than_256
|
||
|
j=256
|
||
|
.rept 5 # j = {256, 128, 64, 32, 16}
|
||
|
.altmacro
|
||
|
LABEL less_than_ %j # less_than_j: Length should be in
|
||
|
# upper lg(j) bits of len_dw
|
||
|
j=(j/2)
|
||
|
shl $1, len_dw # Get next MSB
|
||
|
JNC_LESS_THAN %j
|
||
|
.noaltmacro
|
||
|
i=0
|
||
|
.rept (j/8)
|
||
|
crc32q i(bufptmp), crc_init # Compute crc32 of 8-byte data
|
||
|
i=i+8
|
||
|
.endr
|
||
|
jz do_return # Return if remaining length is zero
|
||
|
add $j, bufptmp # Advance buf
|
||
|
.endr
|
||
|
|
||
|
less_than_8: # Length should be stored in
|
||
|
# upper 3 bits of len_dw
|
||
|
shl $1, len_dw
|
||
|
less_than_8_post_shl1:
|
||
|
jnc less_than_4
|
||
|
crc32l (bufptmp), crc_init_dw # CRC of 4 bytes
|
||
|
jz do_return # return if remaining data is zero
|
||
|
add $4, bufptmp
|
||
|
less_than_4: # Length should be stored in
|
||
|
# upper 2 bits of len_dw
|
||
|
shl $1, len_dw
|
||
|
jnc less_than_2
|
||
|
crc32w (bufptmp), crc_init_dw # CRC of 2 bytes
|
||
|
jz do_return # return if remaining data is zero
|
||
|
add $2, bufptmp
|
||
|
less_than_2: # Length should be stored in the MSB
|
||
|
# of len_dw
|
||
|
shl $1, len_dw
|
||
|
jnc less_than_1
|
||
|
crc32b (bufptmp), crc_init_dw # CRC of 1 byte
|
||
|
less_than_1: # Length should be zero
|
||
|
do_return:
|
||
|
movq crc_init, %rax
|
||
|
popq %rsi
|
||
|
popq %rdi
|
||
|
popq %rbx
|
||
|
ret
|
||
|
ENDPROC(crc_pcl)
|
||
|
|
||
|
.section .rodata, "a", @progbits
|
||
|
################################################################
|
||
|
## jump table Table is 129 entries x 2 bytes each
|
||
|
################################################################
|
||
|
.align 4
|
||
|
jump_table:
|
||
|
i=0
|
||
|
.rept 129
|
||
|
.altmacro
|
||
|
JMPTBL_ENTRY %i
|
||
|
.noaltmacro
|
||
|
i=i+1
|
||
|
.endr
|
||
|
|
||
|
|
||
|
################################################################
|
||
|
## PCLMULQDQ tables
|
||
|
## Table is 128 entries x 2 words (8 bytes) each
|
||
|
################################################################
|
||
|
.align 8
|
||
|
K_table:
|
||
|
.long 0x493c7d27, 0x00000001
|
||
|
.long 0xba4fc28e, 0x493c7d27
|
||
|
.long 0xddc0152b, 0xf20c0dfe
|
||
|
.long 0x9e4addf8, 0xba4fc28e
|
||
|
.long 0x39d3b296, 0x3da6d0cb
|
||
|
.long 0x0715ce53, 0xddc0152b
|
||
|
.long 0x47db8317, 0x1c291d04
|
||
|
.long 0x0d3b6092, 0x9e4addf8
|
||
|
.long 0xc96cfdc0, 0x740eef02
|
||
|
.long 0x878a92a7, 0x39d3b296
|
||
|
.long 0xdaece73e, 0x083a6eec
|
||
|
.long 0xab7aff2a, 0x0715ce53
|
||
|
.long 0x2162d385, 0xc49f4f67
|
||
|
.long 0x83348832, 0x47db8317
|
||
|
.long 0x299847d5, 0x2ad91c30
|
||
|
.long 0xb9e02b86, 0x0d3b6092
|
||
|
.long 0x18b33a4e, 0x6992cea2
|
||
|
.long 0xb6dd949b, 0xc96cfdc0
|
||
|
.long 0x78d9ccb7, 0x7e908048
|
||
|
.long 0xbac2fd7b, 0x878a92a7
|
||
|
.long 0xa60ce07b, 0x1b3d8f29
|
||
|
.long 0xce7f39f4, 0xdaece73e
|
||
|
.long 0x61d82e56, 0xf1d0f55e
|
||
|
.long 0xd270f1a2, 0xab7aff2a
|
||
|
.long 0xc619809d, 0xa87ab8a8
|
||
|
.long 0x2b3cac5d, 0x2162d385
|
||
|
.long 0x65863b64, 0x8462d800
|
||
|
.long 0x1b03397f, 0x83348832
|
||
|
.long 0xebb883bd, 0x71d111a8
|
||
|
.long 0xb3e32c28, 0x299847d5
|
||
|
.long 0x064f7f26, 0xffd852c6
|
||
|
.long 0xdd7e3b0c, 0xb9e02b86
|
||
|
.long 0xf285651c, 0xdcb17aa4
|
||
|
.long 0x10746f3c, 0x18b33a4e
|
||
|
.long 0xc7a68855, 0xf37c5aee
|
||
|
.long 0x271d9844, 0xb6dd949b
|
||
|
.long 0x8e766a0c, 0x6051d5a2
|
||
|
.long 0x93a5f730, 0x78d9ccb7
|
||
|
.long 0x6cb08e5c, 0x18b0d4ff
|
||
|
.long 0x6b749fb2, 0xbac2fd7b
|
||
|
.long 0x1393e203, 0x21f3d99c
|
||
|
.long 0xcec3662e, 0xa60ce07b
|
||
|
.long 0x96c515bb, 0x8f158014
|
||
|
.long 0xe6fc4e6a, 0xce7f39f4
|
||
|
.long 0x8227bb8a, 0xa00457f7
|
||
|
.long 0xb0cd4768, 0x61d82e56
|
||
|
.long 0x39c7ff35, 0x8d6d2c43
|
||
|
.long 0xd7a4825c, 0xd270f1a2
|
||
|
.long 0x0ab3844b, 0x00ac29cf
|
||
|
.long 0x0167d312, 0xc619809d
|
||
|
.long 0xf6076544, 0xe9adf796
|
||
|
.long 0x26f6a60a, 0x2b3cac5d
|
||
|
.long 0xa741c1bf, 0x96638b34
|
||
|
.long 0x98d8d9cb, 0x65863b64
|
||
|
.long 0x49c3cc9c, 0xe0e9f351
|
||
|
.long 0x68bce87a, 0x1b03397f
|
||
|
.long 0x57a3d037, 0x9af01f2d
|
||
|
.long 0x6956fc3b, 0xebb883bd
|
||
|
.long 0x42d98888, 0x2cff42cf
|
||
|
.long 0x3771e98f, 0xb3e32c28
|
||
|
.long 0xb42ae3d9, 0x88f25a3a
|
||
|
.long 0x2178513a, 0x064f7f26
|
||
|
.long 0xe0ac139e, 0x4e36f0b0
|
||
|
.long 0x170076fa, 0xdd7e3b0c
|
||
|
.long 0x444dd413, 0xbd6f81f8
|
||
|
.long 0x6f345e45, 0xf285651c
|
||
|
.long 0x41d17b64, 0x91c9bd4b
|
||
|
.long 0xff0dba97, 0x10746f3c
|
||
|
.long 0xa2b73df1, 0x885f087b
|
||
|
.long 0xf872e54c, 0xc7a68855
|
||
|
.long 0x1e41e9fc, 0x4c144932
|
||
|
.long 0x86d8e4d2, 0x271d9844
|
||
|
.long 0x651bd98b, 0x52148f02
|
||
|
.long 0x5bb8f1bc, 0x8e766a0c
|
||
|
.long 0xa90fd27a, 0xa3c6f37a
|
||
|
.long 0xb3af077a, 0x93a5f730
|
||
|
.long 0x4984d782, 0xd7c0557f
|
||
|
.long 0xca6ef3ac, 0x6cb08e5c
|
||
|
.long 0x234e0b26, 0x63ded06a
|
||
|
.long 0xdd66cbbb, 0x6b749fb2
|
||
|
.long 0x4597456a, 0x4d56973c
|
||
|
.long 0xe9e28eb4, 0x1393e203
|
||
|
.long 0x7b3ff57a, 0x9669c9df
|
||
|
.long 0xc9c8b782, 0xcec3662e
|
||
|
.long 0x3f70cc6f, 0xe417f38a
|
||
|
.long 0x93e106a4, 0x96c515bb
|
||
|
.long 0x62ec6c6d, 0x4b9e0f71
|
||
|
.long 0xd813b325, 0xe6fc4e6a
|
||
|
.long 0x0df04680, 0xd104b8fc
|
||
|
.long 0x2342001e, 0x8227bb8a
|
||
|
.long 0x0a2a8d7e, 0x5b397730
|
||
|
.long 0x6d9a4957, 0xb0cd4768
|
||
|
.long 0xe8b6368b, 0xe78eb416
|
||
|
.long 0xd2c3ed1a, 0x39c7ff35
|
||
|
.long 0x995a5724, 0x61ff0e01
|
||
|
.long 0x9ef68d35, 0xd7a4825c
|
||
|
.long 0x0c139b31, 0x8d96551c
|
||
|
.long 0xf2271e60, 0x0ab3844b
|
||
|
.long 0x0b0bf8ca, 0x0bf80dd2
|
||
|
.long 0x2664fd8b, 0x0167d312
|
||
|
.long 0xed64812d, 0x8821abed
|
||
|
.long 0x02ee03b2, 0xf6076544
|
||
|
.long 0x8604ae0f, 0x6a45d2b2
|
||
|
.long 0x363bd6b3, 0x26f6a60a
|
||
|
.long 0x135c83fd, 0xd8d26619
|
||
|
.long 0x5fabe670, 0xa741c1bf
|
||
|
.long 0x35ec3279, 0xde87806c
|
||
|
.long 0x00bcf5f6, 0x98d8d9cb
|
||
|
.long 0x8ae00689, 0x14338754
|
||
|
.long 0x17f27698, 0x49c3cc9c
|
||
|
.long 0x58ca5f00, 0x5bd2011f
|
||
|
.long 0xaa7c7ad5, 0x68bce87a
|
||
|
.long 0xb5cfca28, 0xdd07448e
|
||
|
.long 0xded288f8, 0x57a3d037
|
||
|
.long 0x59f229bc, 0xdde8f5b9
|
||
|
.long 0x6d390dec, 0x6956fc3b
|
||
|
.long 0x37170390, 0xa3e3e02c
|
||
|
.long 0x6353c1cc, 0x42d98888
|
||
|
.long 0xc4584f5c, 0xd73c7bea
|
||
|
.long 0xf48642e9, 0x3771e98f
|
||
|
.long 0x531377e2, 0x80ff0093
|
||
|
.long 0xdd35bc8d, 0xb42ae3d9
|
||
|
.long 0xb25b29f2, 0x8fe4c34d
|
||
|
.long 0x9a5ede41, 0x2178513a
|
||
|
.long 0xa563905d, 0xdf99fc11
|
||
|
.long 0x45cddf4e, 0xe0ac139e
|
||
|
.long 0xacfa3103, 0x6c23e841
|
||
|
.long 0xa51b6135, 0x170076fa
|