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/* $Id: checksum.h,v 1.17 2001/04/24 01:09:12 davem Exp $ */
#ifndef __SPARC64_CHECKSUM_H
#define __SPARC64_CHECKSUM_H
/* checksum.h: IP/UDP/TCP checksum routines on the V9.
*
* Copyright(C) 1995 Linus Torvalds
* Copyright(C) 1995 Miguel de Icaza
* Copyright(C) 1996 David S. Miller
* Copyright(C) 1996 Eddie C. Dost
* Copyright(C) 1997 Jakub Jelinek
*
* derived from:
* Alpha checksum c-code
* ix86 inline assembly
* RFC1071 Computing the Internet Checksum
*/
#include <asm/uaccess.h>
/* 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
*/
extern unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum);
/* the same as csum_partial, but copies from user space while it
* checksums
*
* here even more important to align src and dst on a 32-bit (or even
* better 64-bit) boundary
*/
extern unsigned int csum_partial_copy_sparc64(const char *src, char *dst, int len, unsigned int sum);
extern __inline__ unsigned int
csum_partial_copy_nocheck (const char *src, char *dst, int len,
unsigned int sum)
{
int ret;
unsigned char cur_ds = current->thread.current_ds.seg;
__asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "i" (ASI_P));
ret = csum_partial_copy_sparc64(src, dst, len, sum);
__asm__ __volatile__ ("wr %%g0, %0, %%asi" : : "r" (cur_ds));
return ret;
}
extern __inline__ unsigned int
csum_partial_copy_from_user(const char *src, char *dst, int len,
unsigned int sum, int *err)
{
__asm__ __volatile__ ("stx %0, [%%sp + 0x7ff + 128]"
: : "r" (err));
return csum_partial_copy_sparc64(src, dst, len, sum);
}
/*
* Copy and checksum to user
*/
#define HAVE_CSUM_COPY_USER
extern unsigned int csum_partial_copy_user_sparc64(const char *src, char *dst, int len, unsigned int sum);
extern __inline__ unsigned int
csum_and_copy_to_user(const char *src, char *dst, int len,
unsigned int sum, int *err)
{
__asm__ __volatile__ ("stx %0, [%%sp + 0x7ff + 128]"
: : "r" (err));
return csum_partial_copy_user_sparc64(src, dst, len, sum);
}
/* ihl is always 5 or greater, almost always is 5, and iph is word aligned
* the majority of the time.
*/
extern __inline__ unsigned short ip_fast_csum(__const__ unsigned char *iph,
unsigned int ihl)
{
unsigned short sum;
/* Note: We must read %2 before we touch %0 for the first time,
* because GCC can legitimately use the same register for
* both operands.
*/
__asm__ __volatile__(
" sub %2, 4, %%g7 ! IEU0\n"
" lduw [%1 + 0x00], %0 ! Load Group\n"
" lduw [%1 + 0x04], %%g2 ! Load Group\n"
" lduw [%1 + 0x08], %%g3 ! Load Group\n"
" addcc %%g2, %0, %0 ! IEU1 1 Load Bubble + Group\n"
" lduw [%1 + 0x0c], %%g2 ! Load\n"
" addccc %%g3, %0, %0 ! Sngle Group no Bubble\n"
" lduw [%1 + 0x10], %%g3 ! Load Group\n"
" addccc %%g2, %0, %0 ! Sngle Group no Bubble\n"
" addc %0, %%g0, %0 ! Sngle Group\n"
"1: addcc %%g3, %0, %0 ! IEU1 Group no Bubble\n"
" add %1, 4, %1 ! IEU0\n"
" addccc %0, %%g0, %0 ! Sngle Group no Bubble\n"
" subcc %%g7, 1, %%g7 ! IEU1 Group\n"
" be,a,pt %%icc, 2f ! CTI\n"
" sll %0, 16, %%g2 ! IEU0\n"
" lduw [%1 + 0x10], %%g3 ! Load Group\n"
" ba,pt %%xcc, 1b ! CTI\n"
" nop ! IEU0\n"
"2: addcc %0, %%g2, %%g2 ! IEU1 Group\n"
" srl %%g2, 16, %0 ! IEU0 Group regdep XXX Scheisse!\n"
" addc %0, %%g0, %0 ! Sngle Group\n"
" xnor %%g0, %0, %0 ! IEU0 Group\n"
" srl %0, 0, %0 ! IEU0 Group XXX Scheisse!\n"
: "=r" (sum), "=&r" (iph)
: "r" (ihl), "1" (iph)
: "g2", "g3", "g7", "cc");
return sum;
}
/* Fold a partial checksum without adding pseudo headers. */
extern __inline__ unsigned short csum_fold(unsigned int sum)
{
unsigned int tmp;
__asm__ __volatile__(
" addcc %0, %1, %1\n"
" srl %1, 16, %1\n"
" addc %1, %%g0, %1\n"
" xnor %%g0, %1, %0\n"
: "=&r" (sum), "=r" (tmp)
: "0" (sum), "1" (sum<<16)
: "cc");
return (sum & 0xffff);
}
extern __inline__ unsigned long csum_tcpudp_nofold(unsigned long saddr,
unsigned long daddr,
unsigned int len,
unsigned short proto,
unsigned int sum)
{
__asm__ __volatile__(
" addcc %1, %0, %0\n"
" addccc %2, %0, %0\n"
" addccc %3, %0, %0\n"
" addc %0, %%g0, %0\n"
: "=r" (sum), "=r" (saddr)
: "r" (daddr), "r" ((proto<<16)+len), "0" (sum), "1" (saddr)
: "cc");
return sum;
}
/*
* computes the checksum of the TCP/UDP pseudo-header
* returns a 16-bit checksum, already complemented
*/
static inline unsigned short int csum_tcpudp_magic(unsigned long saddr,
unsigned long daddr,
unsigned short len,
unsigned short proto,
unsigned int sum)
{
return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
}
#define _HAVE_ARCH_IPV6_CSUM
static __inline__ unsigned short int csum_ipv6_magic(struct in6_addr *saddr,
struct in6_addr *daddr,
__u32 len,
unsigned short proto,
unsigned int sum)
{
__asm__ __volatile__ (
" addcc %3, %4, %%g7\n"
" addccc %5, %%g7, %%g7\n"
" lduw [%2 + 0x0c], %%g2\n"
" lduw [%2 + 0x08], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" lduw [%2 + 0x04], %%g2\n"
" addccc %%g3, %%g7, %%g7\n"
" lduw [%2 + 0x00], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" lduw [%1 + 0x0c], %%g2\n"
" addccc %%g3, %%g7, %%g7\n"
" lduw [%1 + 0x08], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" lduw [%1 + 0x04], %%g2\n"
" addccc %%g3, %%g7, %%g7\n"
" lduw [%1 + 0x00], %%g3\n"
" addccc %%g2, %%g7, %%g7\n"
" addccc %%g3, %%g7, %0\n"
" addc 0, %0, %0\n"
: "=&r" (sum)
: "r" (saddr), "r" (daddr), "r"(htonl(len)),
"r"(htonl(proto)), "r"(sum)
: "g2", "g3", "g7", "cc");
return csum_fold(sum);
}
/* this routine is used for miscellaneous IP-like checksums, mainly in icmp.c */
extern __inline__ unsigned short ip_compute_csum(unsigned char * buff, int len)
{
return csum_fold(csum_partial(buff, len, 0));
}
#endif /* !(__SPARC64_CHECKSUM_H) */
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