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Diffstat (limited to 'include/asm-frv/checksum.h')
| -rw-r--r-- | include/asm-frv/checksum.h | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/include/asm-frv/checksum.h b/include/asm-frv/checksum.h new file mode 100644 index 00000000000..10236f6802d --- /dev/null +++ b/include/asm-frv/checksum.h @@ -0,0 +1,183 @@ +/* checksum.h: FRV checksumming + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program 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. + */ + +#ifndef _ASM_CHECKSUM_H +#define _ASM_CHECKSUM_H + +#include <linux/in6.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 + */ +unsigned int csum_partial(const unsigned char * buff, int len, unsigned int 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 + */ +unsigned int csum_partial_copy(const char *src, char *dst, int len, int 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 unsigned int csum_partial_copy_from_user(const char *src, char *dst, + int len, int sum, int *csum_err); + +#define csum_partial_copy_nocheck(src, dst, len, sum) \ + csum_partial_copy((src), (dst), (len), (sum)) + +/* + * This is a version of ip_compute_csum() optimized for IP headers, + * which always checksum on 4 octet boundaries. + * + */ +static inline +unsigned short ip_fast_csum(unsigned char *iph, unsigned int ihl) +{ + unsigned int tmp, inc, sum = 0; + + asm(" addcc gr0,gr0,gr0,icc0\n" /* clear icc0.C */ + " subi %1,#4,%1 \n" + "0: \n" + " ldu.p @(%1,%3),%4 \n" + " subicc %2,#1,%2,icc1 \n" + " addxcc.p %4,%0,%0,icc0 \n" + " bhi icc1,#2,0b \n" + + /* fold the 33-bit result into 16-bits */ + " addxcc gr0,%0,%0,icc0 \n" + " srli %0,#16,%1 \n" + " sethi #0,%0 \n" + " add %1,%0,%0 \n" + " srli %0,#16,%1 \n" + " add %1,%0,%0 \n" + + : "=r" (sum), "=r" (iph), "=r" (ihl), "=r" (inc), "=&r"(tmp) + : "0" (sum), "1" (iph), "2" (ihl), "3" (4), + "m"(*(volatile struct { int _[100]; } *)iph) + : "icc0", "icc1" + ); + + return ~sum; +} + +/* + * Fold a partial checksum + */ +static inline unsigned int csum_fold(unsigned int sum) +{ + unsigned int tmp; + + asm(" srli %0,#16,%1 \n" + " sethi #0,%0 \n" + " add %1,%0,%0 \n" + " srli %0,#16,%1 \n" + " add %1,%0,%0 \n" + : "=r"(sum), "=&r"(tmp) + : "0"(sum) + ); + + return ~sum; +} + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 16-bit checksum, already complemented + */ +static inline unsigned int +csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len, + unsigned short proto, unsigned int sum) +{ + asm(" addcc %1,%0,%0,icc0 \n" + " addxcc %2,%0,%0,icc0 \n" + " addxcc %3,%0,%0,icc0 \n" + " addxcc gr0,%0,%0,icc0 \n" + : "=r" (sum) + : "r" (daddr), "r" (saddr), "r" (len + proto), "0"(sum) + : "icc0" + ); + return sum; +} + +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)); +} + +/* + * this routine is used for miscellaneous IP-like checksums, mainly + * in icmp.c + */ +extern unsigned short ip_compute_csum(const unsigned char * buff, int len); + +#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) +{ + unsigned long tmp, tmp2; + + asm(" addcc %2,%0,%0,icc0 \n" + + /* add up the source addr */ + " ldi @(%3,0),%1 \n" + " addxcc %1,%0,%0,icc0 \n" + " ldi @(%3,4),%2 \n" + " addxcc %2,%0,%0,icc0 \n" + " ldi @(%3,8),%1 \n" + " addxcc %1,%0,%0,icc0 \n" + " ldi @(%3,12),%2 \n" + " addxcc %2,%0,%0,icc0 \n" + + /* add up the dest addr */ + " ldi @(%4,0),%1 \n" + " addxcc %1,%0,%0,icc0 \n" + " ldi @(%4,4),%2 \n" + " addxcc %2,%0,%0,icc0 \n" + " ldi @(%4,8),%1 \n" + " addxcc %1,%0,%0,icc0 \n" + " ldi @(%4,12),%2 \n" + " addxcc %2,%0,%0,icc0 \n" + + /* fold the 33-bit result into 16-bits */ + " addxcc gr0,%0,%0,icc0 \n" + " srli %0,#16,%1 \n" + " sethi #0,%0 \n" + " add %1,%0,%0 \n" + " srli %0,#16,%1 \n" + " add %1,%0,%0 \n" + + : "=r" (sum), "=&r" (tmp), "=r" (tmp2) + : "r" (saddr), "r" (daddr), "0" (sum), "2" (len + proto) + : "icc0" + ); + + return ~sum; +} + +#endif /* _ASM_CHECKSUM_H */ |