| /* |
| * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> |
| * Copyright (C) 2004 Microtronix Datacom Ltd. |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| */ |
| |
| #ifndef _ASM_NIOS_CHECKSUM_H |
| #define _ASM_NIOS_CHECKSUM_H |
| |
| /* Take these from lib/checksum.c */ |
| extern __wsum csum_partial(const void *buff, int len, __wsum sum); |
| extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); |
| extern __sum16 ip_compute_csum(const void *buff, int len); |
| |
| /* |
| * Fold a partial checksum |
| */ |
| static inline __sum16 csum_fold(__wsum sum) |
| { |
| __asm__ __volatile__( |
| "add %0, %1, %0\n" |
| "cmpltu r8, %0, %1\n" |
| "srli %0, %0, 16\n" |
| "add %0, %0, r8\n" |
| "nor %0, %0, %0\n" |
| : "=r" (sum) |
| : "r" (sum << 16), "0" (sum) |
| : "r8"); |
| return (__force __sum16) sum; |
| } |
| |
| /* |
| * computes the checksum of the TCP/UDP pseudo-header |
| * returns a 16-bit checksum, already complemented |
| */ |
| #define csum_tcpudp_nofold csum_tcpudp_nofold |
| static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, |
| __u32 len, __u8 proto, |
| __wsum sum) |
| { |
| __asm__ __volatile__( |
| "add %0, %1, %0\n" |
| "cmpltu r8, %0, %1\n" |
| "add %0, %0, r8\n" /* add carry */ |
| "add %0, %2, %0\n" |
| "cmpltu r8, %0, %2\n" |
| "add %0, %0, r8\n" /* add carry */ |
| "add %0, %3, %0\n" |
| "cmpltu r8, %0, %3\n" |
| "add %0, %0, r8\n" /* add carry */ |
| : "=r" (sum), "=r" (saddr) |
| : "r" (daddr), "r" ((len + proto) << 8), |
| "0" (sum), |
| "1" (saddr) |
| : "r8"); |
| |
| return sum; |
| } |
| |
| static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, |
| __u32 len, __u8 proto, |
| __wsum sum) |
| { |
| return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); |
| } |
| |
| #endif /* _ASM_NIOS_CHECKSUM_H */ |
