1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __SPARC64_CHECKSUM_H
3#define __SPARC64_CHECKSUM_H
4
5/*  checksum.h:  IP/UDP/TCP checksum routines on the V9.
6 *
7 *  Copyright(C) 1995 Linus Torvalds
8 *  Copyright(C) 1995 Miguel de Icaza
9 *  Copyright(C) 1996 David S. Miller
10 *  Copyright(C) 1996 Eddie C. Dost
11 *  Copyright(C) 1997 Jakub Jelinek
12 *
13 * derived from:
14 *	Alpha checksum c-code
15 *      ix86 inline assembly
16 *      RFC1071 Computing the Internet Checksum
17 */
18
19#include <linux/in6.h>
20#include <linux/uaccess.h>
21
22/* computes the checksum of a memory block at buff, length len,
23 * and adds in "sum" (32-bit)
24 *
25 * returns a 32-bit number suitable for feeding into itself
26 * or csum_tcpudp_magic
27 *
28 * this function must be called with even lengths, except
29 * for the last fragment, which may be odd
30 *
31 * it's best to have buff aligned on a 32-bit boundary
32 */
33__wsum csum_partial(const void * buff, int len, __wsum sum);
34
35/* the same as csum_partial, but copies from user space while it
36 * checksums
37 *
38 * here even more important to align src and dst on a 32-bit (or even
39 * better 64-bit) boundary
40 */
41__wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);
42__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len);
43__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len);
44
45/* ihl is always 5 or greater, almost always is 5, and iph is word aligned
46 * the majority of the time.
47 */
48__sum16 ip_fast_csum(const void *iph, unsigned int ihl);
49
50/* Fold a partial checksum without adding pseudo headers. */
51static inline __sum16 csum_fold(__wsum sum)
52{
53	unsigned int tmp;
54
55	__asm__ __volatile__(
56"	addcc		%0, %1, %1\n"
57"	srl		%1, 16, %1\n"
58"	addc		%1, %%g0, %1\n"
59"	xnor		%%g0, %1, %0\n"
60	: "=&r" (sum), "=r" (tmp)
61	: "0" (sum), "1" ((__force u32)sum<<16)
62	: "cc");
63	return (__force __sum16)sum;
64}
65
66static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
67					__u32 len, __u8 proto,
68					__wsum sum)
69{
70	__asm__ __volatile__(
71"	addcc		%1, %0, %0\n"
72"	addccc		%2, %0, %0\n"
73"	addccc		%3, %0, %0\n"
74"	addc		%0, %%g0, %0\n"
75	: "=r" (sum), "=r" (saddr)
76	: "r" (daddr), "r" (proto + len), "0" (sum), "1" (saddr)
77	: "cc");
78	return sum;
79}
80
81/*
82 * computes the checksum of the TCP/UDP pseudo-header
83 * returns a 16-bit checksum, already complemented
84 */
85static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
86					__u32 len, __u8 proto,
87					__wsum sum)
88{
89	return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
90}
91
92#define _HAVE_ARCH_IPV6_CSUM
93
94static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
95				      const struct in6_addr *daddr,
96				      __u32 len, __u8 proto, __wsum sum)
97{
98	__asm__ __volatile__ (
99"	addcc		%3, %4, %%g7\n"
100"	addccc		%5, %%g7, %%g7\n"
101"	lduw		[%2 + 0x0c], %%g2\n"
102"	lduw		[%2 + 0x08], %%g3\n"
103"	addccc		%%g2, %%g7, %%g7\n"
104"	lduw		[%2 + 0x04], %%g2\n"
105"	addccc		%%g3, %%g7, %%g7\n"
106"	lduw		[%2 + 0x00], %%g3\n"
107"	addccc		%%g2, %%g7, %%g7\n"
108"	lduw		[%1 + 0x0c], %%g2\n"
109"	addccc		%%g3, %%g7, %%g7\n"
110"	lduw		[%1 + 0x08], %%g3\n"
111"	addccc		%%g2, %%g7, %%g7\n"
112"	lduw		[%1 + 0x04], %%g2\n"
113"	addccc		%%g3, %%g7, %%g7\n"
114"	lduw		[%1 + 0x00], %%g3\n"
115"	addccc		%%g2, %%g7, %%g7\n"
116"	addccc		%%g3, %%g7, %0\n"
117"	addc		0, %0, %0\n"
118	: "=&r" (sum)
119	: "r" (saddr), "r" (daddr), "r"(htonl(len)),
120	  "r"(htonl(proto)), "r"(sum)
121	: "g2", "g3", "g7", "cc");
122
123	return csum_fold(sum);
124}
125
126/* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
127static inline __sum16 ip_compute_csum(const void *buff, int len)
128{
129	return csum_fold(csum_partial(buff, len, 0));
130}
131
132#define HAVE_ARCH_CSUM_ADD
133static inline __wsum csum_add(__wsum csum, __wsum addend)
134{
135	__asm__ __volatile__(
136		"addcc   %0, %1, %0\n"
137		"addx    %0, %%g0, %0"
138		: "=r" (csum)
139		: "r" (addend), "0" (csum));
140
141	return csum;
142}
143
144#endif /* !(__SPARC64_CHECKSUM_H) */
145