1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _M68K_CHECKSUM_H
3#define _M68K_CHECKSUM_H
4
5#include <linux/in6.h>
6
7#ifdef CONFIG_GENERIC_CSUM
8#include <asm-generic/checksum.h>
9#else
10
11/*
12 * computes the checksum of a memory block at buff, length len,
13 * and adds in "sum" (32-bit)
14 *
15 * returns a 32-bit number suitable for feeding into itself
16 * or csum_tcpudp_magic
17 *
18 * this function must be called with even lengths, except
19 * for the last fragment, which may be odd
20 *
21 * it's best to have buff aligned on a 32-bit boundary
22 */
23__wsum csum_partial(const void *buff, int len, __wsum sum);
24
25/*
26 * the same as csum_partial, but copies from src while it
27 * checksums
28 *
29 * here even more important to align src and dst on a 32-bit (or even
30 * better 64-bit) boundary
31 */
32
33#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
34#define _HAVE_ARCH_CSUM_AND_COPY
35extern __wsum csum_and_copy_from_user(const void __user *src,
36						void *dst,
37						int len);
38
39extern __wsum csum_partial_copy_nocheck(const void *src,
40					      void *dst, int len);
41
42/*
43 *	This is a version of ip_fast_csum() optimized for IP headers,
44 *	which always checksum on 4 octet boundaries.
45 */
46static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
47{
48	unsigned int sum = 0;
49	unsigned long tmp;
50
51	__asm__ ("subqw #1,%2\n"
52		 "1:\t"
53		 "movel %1@+,%3\n\t"
54		 "addxl %3,%0\n\t"
55		 "dbra  %2,1b\n\t"
56		 "movel %0,%3\n\t"
57		 "swap  %3\n\t"
58		 "addxw %3,%0\n\t"
59		 "clrw  %3\n\t"
60		 "addxw %3,%0\n\t"
61		 : "=d" (sum), "=&a" (iph), "=&d" (ihl), "=&d" (tmp)
62		 : "0" (sum), "1" (iph), "2" (ihl)
63		 : "memory");
64	return (__force __sum16)~sum;
65}
66
67static inline __sum16 csum_fold(__wsum sum)
68{
69	unsigned int tmp = (__force u32)sum;
70
71	__asm__("swap %1\n\t"
72		"addw %1, %0\n\t"
73		"clrw %1\n\t"
74		"addxw %1, %0"
75		: "=&d" (sum), "=&d" (tmp)
76		: "0" (sum), "1" (tmp));
77
78	return (__force __sum16)~sum;
79}
80
81static inline __wsum
82csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
83		  unsigned short proto, __wsum sum)
84{
85	__asm__ ("addl  %2,%0\n\t"
86		 "addxl %3,%0\n\t"
87		 "addxl %4,%0\n\t"
88		 "clrl %1\n\t"
89		 "addxl %1,%0"
90		 : "=&d" (sum), "=d" (saddr)
91		 : "g" (daddr), "1" (saddr), "d" (len + proto),
92		   "0" (sum));
93	return sum;
94}
95
96
97/*
98 * computes the checksum of the TCP/UDP pseudo-header
99 * returns a 16-bit checksum, already complemented
100 */
101static inline __sum16
102csum_tcpudp_magic(__be32 saddr, __be32 daddr, unsigned short len,
103		  unsigned short proto, __wsum sum)
104{
105	return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
106}
107
108/*
109 * this routine is used for miscellaneous IP-like checksums, mainly
110 * in icmp.c
111 */
112
113static inline __sum16 ip_compute_csum(const void *buff, int len)
114{
115	return csum_fold (csum_partial(buff, len, 0));
116}
117
118#define _HAVE_ARCH_IPV6_CSUM
119static __inline__ __sum16
120csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr,
121		__u32 len, __u8 proto, __wsum sum)
122{
123	register unsigned long tmp;
124	__asm__("addl %2@,%0\n\t"
125		"movel %2@(4),%1\n\t"
126		"addxl %1,%0\n\t"
127		"movel %2@(8),%1\n\t"
128		"addxl %1,%0\n\t"
129		"movel %2@(12),%1\n\t"
130		"addxl %1,%0\n\t"
131		"movel %3@,%1\n\t"
132		"addxl %1,%0\n\t"
133		"movel %3@(4),%1\n\t"
134		"addxl %1,%0\n\t"
135		"movel %3@(8),%1\n\t"
136		"addxl %1,%0\n\t"
137		"movel %3@(12),%1\n\t"
138		"addxl %1,%0\n\t"
139		"addxl %4,%0\n\t"
140		"clrl %1\n\t"
141		"addxl %1,%0"
142		: "=&d" (sum), "=&d" (tmp)
143		: "a" (saddr), "a" (daddr), "d" (len + proto),
144		  "0" (sum));
145
146	return csum_fold(sum);
147}
148
149#endif /* CONFIG_GENERIC_CSUM */
150#endif /* _M68K_CHECKSUM_H */
151