/*
* arch/ubicom32/include/asm/checksum.h
* Checksum utilities for Ubicom32 architecture.
*
* (C) Copyright 2009, Ubicom, Inc.
*
* This file is part of the Ubicom32 Linux Kernel Port.
*
* The Ubicom32 Linux Kernel Port is free software: you can redistribute
* it and/or modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, either version 2 of the
* License, or (at your option) any later version.
*
* The Ubicom32 Linux Kernel Port is distributed in the hope that it
* will be useful, but WITHOUT ANY WARRANTY; without even the implied
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with the Ubicom32 Linux Kernel Port. If not,
* see .
*
* Ubicom32 implementation derived from (with many thanks):
* arch/m68knommu
* arch/blackfin
* arch/parisc
*/
#ifndef _ASM_UBICOM32_CHECKSUM_H
#define _ASM_UBICOM32_CHECKSUM_H
#include
/*
* computes the checksum of a memory block at buff, length len,
* and adds in "sum" (32-bit)
*
* returns a 32-bit number suitable for feeding into itself
* or csum_tcpudp_magic
*
* this function must be called with even lengths, except
* for the last fragment, which may be odd
*
* it's best to have buff aligned on a 32-bit boundary
*/
__wsum csum_partial(const void *buff, int len, __wsum sum);
/*
* the same as csum_partial, but copies from src while it
* checksums
*
* here even more important to align src and dst on a 32-bit (or even
* better 64-bit) boundary
*/
__wsum csum_partial_copy_nocheck(const void *src, void *dst,
int len, __wsum sum);
/*
* the same as csum_partial_copy, but copies from user space.
*
* here even more important to align src and dst on a 32-bit (or even
* better 64-bit) boundary
*/
extern __wsum csum_partial_copy_from_user(const void __user *src,
void *dst, int len, __wsum sum, int *csum_err);
__sum16 ip_fast_csum(const void *iph, unsigned int ihl);
/*
* Fold a partial checksum
*/
static inline __sum16 csum_fold(__wsum sum)
{
asm volatile (
" lsr.4 d15, %0, #16 \n\t"
" bfextu %0, %0, #16 \n\t"
" add.4 %0, d15, %0 \n\t"
" lsr.4 d15, %0, #16 \n\t"
" bfextu %0, %0, #16 \n\t"
" add.4 %0, d15, %0 \n\t"
: "=&d" (sum)
: "0"(sum)
: "d15"
);
return (__force __sum16)~sum;
}
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
*/
static inline __wsum
csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
unsigned short proto, __wsum sum)
{
asm volatile (
" add.4 %0, %2, %0 \n\t"
" addc %0, %3, %0 \n\t"
" addc %0, %4, %0 \n\t"
" addc %0, %5, %0 \n\t"
" addc %0, #0, %0 \n\t"
: "=&d" (sum)
: "0"(sum), "r" (saddr), "r" (daddr), "r" (len), "r"(proto)
);
return sum;
}
static inline __sum16
csum_tcpudp_magic(__be32 saddr, __be32 daddr, unsigned short len,
unsigned short proto, __wsum sum)
{
return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
}
/*
* this routine is used for miscellaneous IP-like checksums, mainly
* in icmp.c
*/
extern __sum16 ip_compute_csum(const void *buff, int len);
#define _HAVE_ARCH_IPV6_CSUM
static __inline__ __sum16
csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr,
__u32 len, unsigned short proto, __wsum sum)
{
asm volatile (
" add.4 %0, 0(%2), %0 \n\t"
" addc %0, 4(%2), %0 \n\t"
" addc %0, 8(%2), %0 \n\t"
" addc %0, 12(%2), %0 \n\t"
" addc %0, 0(%3), %0 \n\t"
" addc %0, 4(%3), %0 \n\t"
" addc %0, 8(%3), %0 \n\t"
" addc %0, 12(%3), %0 \n\t"
" addc %0, %4, %0 \n\t"
" addc %0, #0, %0 \n\t"
: "=&d" (sum)
: "0" (sum), "a" (saddr), "a" (daddr), "d" (len + proto)
);
return csum_fold(sum);
}
#endif /* _ASM_UBICOM32_CHECKSUM_H */