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Diffstat (limited to 'target/linux/ubicom32/files/arch/ubicom32/include/asm/checksum.h')
| -rw-r--r-- | target/linux/ubicom32/files/arch/ubicom32/include/asm/checksum.h | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/target/linux/ubicom32/files/arch/ubicom32/include/asm/checksum.h b/target/linux/ubicom32/files/arch/ubicom32/include/asm/checksum.h new file mode 100644 index 000000000..25f8ca61c --- /dev/null +++ b/target/linux/ubicom32/files/arch/ubicom32/include/asm/checksum.h @@ -0,0 +1,149 @@ +/* + * 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 <http://www.gnu.org/licenses/>. + * + * Ubicom32 implementation derived from (with many thanks): + * arch/m68knommu + * arch/blackfin + * arch/parisc + */ +#ifndef _ASM_UBICOM32_CHECKSUM_H +#define _ASM_UBICOM32_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 + */ +__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 */ |