From 31b4edc67b75658ce5e2d41f2fc87331f4b26d49 Mon Sep 17 00:00:00 2001 From: bhgv Date: Sun, 10 May 2020 02:59:23 +0300 Subject: a try to add support of FreeRTOS riscV-64 (k210 cpu). first step --- libiot/lfs/lfs_util.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 libiot/lfs/lfs_util.c (limited to 'libiot/lfs/lfs_util.c') diff --git a/libiot/lfs/lfs_util.c b/libiot/lfs/lfs_util.c new file mode 100644 index 0000000..9ca0756 --- /dev/null +++ b/libiot/lfs/lfs_util.c @@ -0,0 +1,31 @@ +/* + * lfs util functions + * + * Copyright (c) 2017, Arm Limited. All rights reserved. + * SPDX-License-Identifier: BSD-3-Clause + */ +#include "lfs_util.h" + +// Only compile if user does not provide custom config +#ifndef LFS_CONFIG + + +// Software CRC implementation with small lookup table +void lfs_crc(uint32_t *restrict crc, const void *buffer, size_t size) { + static const uint32_t rtable[16] = { + 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac, + 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c, + 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c, + 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c, + }; + + const uint8_t *data = buffer; + + for (size_t i = 0; i < size; i++) { + *crc = (*crc >> 4) ^ rtable[(*crc ^ (data[i] >> 0)) & 0xf]; + *crc = (*crc >> 4) ^ rtable[(*crc ^ (data[i] >> 4)) & 0xf]; + } +} + + +#endif -- cgit v1.2.3