--- /dev/null
+/*
+ * 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 */
projects / openwrt.git / blobdiff