From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/tile/lib/checksum.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 arch/tile/lib/checksum.c (limited to 'arch/tile/lib/checksum.c') diff --git a/arch/tile/lib/checksum.c b/arch/tile/lib/checksum.c new file mode 100644 index 000000000..c3ca3e64d --- /dev/null +++ b/arch/tile/lib/checksum.c @@ -0,0 +1,89 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * 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, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * Support code for the main lib/checksum.c. + */ + +#include +#include + +__wsum do_csum(const unsigned char *buff, int len) +{ + int odd, count; + unsigned long result = 0; + + if (len <= 0) + goto out; + odd = 1 & (unsigned long) buff; + if (odd) { + result = (*buff << 8); + len--; + buff++; + } + count = len >> 1; /* nr of 16-bit words.. */ + if (count) { + if (2 & (unsigned long) buff) { + result += *(const unsigned short *)buff; + count--; + len -= 2; + buff += 2; + } + count >>= 1; /* nr of 32-bit words.. */ + if (count) { +#ifdef __tilegx__ + if (4 & (unsigned long) buff) { + unsigned int w = *(const unsigned int *)buff; + result = __insn_v2sadau(result, w, 0); + count--; + len -= 4; + buff += 4; + } + count >>= 1; /* nr of 64-bit words.. */ +#endif + + /* + * This algorithm could wrap around for very + * large buffers, but those should be impossible. + */ + BUG_ON(count >= 65530); + + while (count) { + unsigned long w = *(const unsigned long *)buff; + count--; + buff += sizeof(w); +#ifdef __tilegx__ + result = __insn_v2sadau(result, w, 0); +#else + result = __insn_sadah_u(result, w, 0); +#endif + } +#ifdef __tilegx__ + if (len & 4) { + unsigned int w = *(const unsigned int *)buff; + result = __insn_v2sadau(result, w, 0); + buff += 4; + } +#endif + } + if (len & 2) { + result += *(const unsigned short *) buff; + buff += 2; + } + } + if (len & 1) + result += *buff; + result = csum_long(result); + if (odd) + result = swab16(result); +out: + return result; +} -- cgit v1.2.3-54-g00ecf