diff options
Diffstat (limited to 'drivers/net/ethernet/mellanox/mlx5/core/steering/dr_crc32.c')
| -rw-r--r-- | drivers/net/ethernet/mellanox/mlx5/core/steering/dr_crc32.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/steering/dr_crc32.c b/drivers/net/ethernet/mellanox/mlx5/core/steering/dr_crc32.c new file mode 100644 index 000000000000..9e2eccbb1eb8 --- /dev/null +++ b/drivers/net/ethernet/mellanox/mlx5/core/steering/dr_crc32.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB +/* Copyright (c) 2019 Mellanox Technologies. */ + +/* Copyright (c) 2011-2015 Stephan Brumme. All rights reserved. + * Slicing-by-16 contributed by Bulat Ziganshin + * + * This software is provided 'as-is', without any express or implied warranty. + * In no event will the author be held liable for any damages arising from the + * of this software. + * + * Permission is granted to anyone to use this software for any purpose, + * including commercial applications, and to alter it and redistribute it + * freely, subject to the following restrictions: + * + * 1. The origin of this software must not be misrepresented; you must not + * claim that you wrote the original software. + * 2. If you use this software in a product, an acknowledgment in the product + * documentation would be appreciated but is not required. + * 3. Altered source versions must be plainly marked as such, and must not be + * misrepresented as being the original software. + * + * Taken from http://create.stephan-brumme.com/crc32/ and adapted. + */ + +#include "dr_types.h" + +#define DR_STE_CRC_POLY 0xEDB88320L + +static u32 dr_ste_crc_tab32[8][256]; + +static void dr_crc32_calc_lookup_entry(u32 (*tbl)[256], u8 i, u8 j) +{ + tbl[i][j] = (tbl[i - 1][j] >> 8) ^ tbl[0][tbl[i - 1][j] & 0xff]; +} + +void mlx5dr_crc32_init_table(void) +{ + u32 crc, i, j; + + for (i = 0; i < 256; i++) { + crc = i; + for (j = 0; j < 8; j++) { + if (crc & 0x00000001L) + crc = (crc >> 1) ^ DR_STE_CRC_POLY; + else + crc = crc >> 1; + } + dr_ste_crc_tab32[0][i] = crc; + } + + /* Init CRC lookup tables according to crc_slice_8 algorithm */ + for (i = 0; i < 256; i++) { + dr_crc32_calc_lookup_entry(dr_ste_crc_tab32, 1, i); + dr_crc32_calc_lookup_entry(dr_ste_crc_tab32, 2, i); + dr_crc32_calc_lookup_entry(dr_ste_crc_tab32, 3, i); + dr_crc32_calc_lookup_entry(dr_ste_crc_tab32, 4, i); + dr_crc32_calc_lookup_entry(dr_ste_crc_tab32, 5, i); + dr_crc32_calc_lookup_entry(dr_ste_crc_tab32, 6, i); + dr_crc32_calc_lookup_entry(dr_ste_crc_tab32, 7, i); + } +} + +/* Compute CRC32 (Slicing-by-8 algorithm) */ +u32 mlx5dr_crc32_slice8_calc(const void *input_data, size_t length) +{ + const u32 *curr = (const u32 *)input_data; + const u8 *curr_char; + u32 crc = 0, one, two; + + if (!input_data) + return 0; + + /* Process eight bytes at once (Slicing-by-8) */ + while (length >= 8) { + one = *curr++ ^ crc; + two = *curr++; + + crc = dr_ste_crc_tab32[0][(two >> 24) & 0xff] + ^ dr_ste_crc_tab32[1][(two >> 16) & 0xff] + ^ dr_ste_crc_tab32[2][(two >> 8) & 0xff] + ^ dr_ste_crc_tab32[3][two & 0xff] + ^ dr_ste_crc_tab32[4][(one >> 24) & 0xff] + ^ dr_ste_crc_tab32[5][(one >> 16) & 0xff] + ^ dr_ste_crc_tab32[6][(one >> 8) & 0xff] + ^ dr_ste_crc_tab32[7][one & 0xff]; + + length -= 8; + } + + curr_char = (const u8 *)curr; + /* Remaining 1 to 7 bytes (standard algorithm) */ + while (length-- != 0) + crc = (crc >> 8) ^ dr_ste_crc_tab32[0][(crc & 0xff) + ^ *curr_char++]; + + return ((crc >> 24) & 0xff) | ((crc << 8) & 0xff0000) | + ((crc >> 8) & 0xff00) | ((crc << 24) & 0xff000000); +} |