1 /* 2 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch> 3 * Copyright (C) 2004 Microtronix Datacom Ltd. 4 * 5 * This file is subject to the terms and conditions of the GNU General Public 6 * License. See the file "COPYING" in the main directory of this archive 7 * for more details. 8 */ 9 10 #ifndef _ASM_NIOS_CHECKSUM_H 11 #define _ASM_NIOS_CHECKSUM_H 12 13 /* Take these from lib/checksum.c */ 14 extern __wsum csum_partial(const void *buff, int len, __wsum sum); 15 extern __wsum csum_partial_copy(const void *src, void *dst, int len, 16 __wsum sum); 17 extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, 18 int len, __wsum sum, int *csum_err); 19 #define csum_partial_copy_nocheck(src, dst, len, sum) \ 20 csum_partial_copy((src), (dst), (len), (sum)) 21 22 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); 23 extern __sum16 ip_compute_csum(const void *buff, int len); 24 25 /* 26 * Fold a partial checksum 27 */ 28 static inline __sum16 csum_fold(__wsum sum) 29 { 30 __asm__ __volatile__( 31 "add %0, %1, %0\n" 32 "cmpltu r8, %0, %1\n" 33 "srli %0, %0, 16\n" 34 "add %0, %0, r8\n" 35 "nor %0, %0, %0\n" 36 : "=r" (sum) 37 : "r" (sum << 16), "0" (sum) 38 : "r8"); 39 return (__force __sum16) sum; 40 } 41 42 /* 43 * computes the checksum of the TCP/UDP pseudo-header 44 * returns a 16-bit checksum, already complemented 45 */ 46 #define csum_tcpudp_nofold csum_tcpudp_nofold 47 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, 48 __u32 len, __u8 proto, 49 __wsum sum) 50 { 51 __asm__ __volatile__( 52 "add %0, %1, %0\n" 53 "cmpltu r8, %0, %1\n" 54 "add %0, %0, r8\n" /* add carry */ 55 "add %0, %2, %0\n" 56 "cmpltu r8, %0, %2\n" 57 "add %0, %0, r8\n" /* add carry */ 58 "add %0, %3, %0\n" 59 "cmpltu r8, %0, %3\n" 60 "add %0, %0, r8\n" /* add carry */ 61 : "=r" (sum), "=r" (saddr) 62 : "r" (daddr), "r" ((len + proto) << 8), 63 "0" (sum), 64 "1" (saddr) 65 : "r8"); 66 67 return sum; 68 } 69 70 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, 71 __u32 len, __u8 proto, 72 __wsum sum) 73 { 74 return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); 75 } 76 77 #endif /* _ASM_NIOS_CHECKSUM_H */ 78