summaryrefslogtreecommitdiff
path: root/include/asm-frv/checksum.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-frv/checksum.h
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-frv/checksum.h')
-rw-r--r--include/asm-frv/checksum.h183
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 000000000000..10236f6802db
--- /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 */