1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
3*4882a593Smuzhiyun * Copyright (C) 2004 Microtronix Datacom Ltd.
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * This file is subject to the terms and conditions of the GNU General Public
6*4882a593Smuzhiyun * License. See the file "COPYING" in the main directory of this archive
7*4882a593Smuzhiyun * for more details.
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #ifndef _ASM_NIOS_CHECKSUM_H
11*4882a593Smuzhiyun #define _ASM_NIOS_CHECKSUM_H
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun /* Take these from lib/checksum.c */
14*4882a593Smuzhiyun extern __wsum csum_partial(const void *buff, int len, __wsum sum);
15*4882a593Smuzhiyun extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
16*4882a593Smuzhiyun extern __sum16 ip_compute_csum(const void *buff, int len);
17*4882a593Smuzhiyun
18*4882a593Smuzhiyun /*
19*4882a593Smuzhiyun * Fold a partial checksum
20*4882a593Smuzhiyun */
csum_fold(__wsum sum)21*4882a593Smuzhiyun static inline __sum16 csum_fold(__wsum sum)
22*4882a593Smuzhiyun {
23*4882a593Smuzhiyun __asm__ __volatile__(
24*4882a593Smuzhiyun "add %0, %1, %0\n"
25*4882a593Smuzhiyun "cmpltu r8, %0, %1\n"
26*4882a593Smuzhiyun "srli %0, %0, 16\n"
27*4882a593Smuzhiyun "add %0, %0, r8\n"
28*4882a593Smuzhiyun "nor %0, %0, %0\n"
29*4882a593Smuzhiyun : "=r" (sum)
30*4882a593Smuzhiyun : "r" (sum << 16), "0" (sum)
31*4882a593Smuzhiyun : "r8");
32*4882a593Smuzhiyun return (__force __sum16) sum;
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun /*
36*4882a593Smuzhiyun * computes the checksum of the TCP/UDP pseudo-header
37*4882a593Smuzhiyun * returns a 16-bit checksum, already complemented
38*4882a593Smuzhiyun */
39*4882a593Smuzhiyun #define csum_tcpudp_nofold csum_tcpudp_nofold
csum_tcpudp_nofold(__be32 saddr,__be32 daddr,__u32 len,__u8 proto,__wsum sum)40*4882a593Smuzhiyun static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
41*4882a593Smuzhiyun __u32 len, __u8 proto,
42*4882a593Smuzhiyun __wsum sum)
43*4882a593Smuzhiyun {
44*4882a593Smuzhiyun __asm__ __volatile__(
45*4882a593Smuzhiyun "add %0, %1, %0\n"
46*4882a593Smuzhiyun "cmpltu r8, %0, %1\n"
47*4882a593Smuzhiyun "add %0, %0, r8\n" /* add carry */
48*4882a593Smuzhiyun "add %0, %2, %0\n"
49*4882a593Smuzhiyun "cmpltu r8, %0, %2\n"
50*4882a593Smuzhiyun "add %0, %0, r8\n" /* add carry */
51*4882a593Smuzhiyun "add %0, %3, %0\n"
52*4882a593Smuzhiyun "cmpltu r8, %0, %3\n"
53*4882a593Smuzhiyun "add %0, %0, r8\n" /* add carry */
54*4882a593Smuzhiyun : "=r" (sum), "=r" (saddr)
55*4882a593Smuzhiyun : "r" (daddr), "r" ((len + proto) << 8),
56*4882a593Smuzhiyun "0" (sum),
57*4882a593Smuzhiyun "1" (saddr)
58*4882a593Smuzhiyun : "r8");
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun return sum;
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
csum_tcpudp_magic(__be32 saddr,__be32 daddr,__u32 len,__u8 proto,__wsum sum)63*4882a593Smuzhiyun static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
64*4882a593Smuzhiyun __u32 len, __u8 proto,
65*4882a593Smuzhiyun __wsum sum)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun #endif /* _ASM_NIOS_CHECKSUM_H */
71