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diff --git a/target/linux/ubicom32/files/arch/ubicom32/lib/checksum.c b/target/linux/ubicom32/files/arch/ubicom32/lib/checksum.c
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+/*
+ * arch/ubicom32/lib/checksum.c
+ * Optimized checksum utilities for IP.
+ *
+ * (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
+ */
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * IP/TCP/UDP checksumming routines
+ *
+ * Authors: Jorge Cwik, <jorge@laser.satlink.net>
+ * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
+ * Tom May, <ftom@netcom.com>
+ * Andreas Schwab, <schwab@issan.informatik.uni-dortmund.de>
+ * Lots of code moved from tcp.c and ip.c; see those files
+ * for more names.
+ *
+ * 03/02/96 Jes Sorensen, Andreas Schwab, Roman Hodek:
+ * Fixed some nasty bugs, causing some horrible crashes.
+ * A: At some points, the sum (%0) was used as
+ * length-counter instead of the length counter
+ * (%1). Thanks to Roman Hodek for pointing this out.
+ * B: GCC seems to mess up if one uses too many
+ * data-registers to hold input values and one tries to
+ * specify d0 and d1 as scratch registers. Letting gcc choose these
+ * registers itself solves the problem.
+ *
+ * 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.
+ */
+
+/* Revised by Kenneth Albanowski for m68knommu. Basic problem: unaligned access kills, so most
+ of the assembly has to go. */
+
+#include <linux/module.h>
+#include <net/checksum.h>
+
+static unsigned long do_csum(const unsigned char * buff, int len)
+{
+ int count;
+ unsigned long result = 0;
+
+ /*
+ * The following optimized assembly code cannot handle data length less than 7 bytes!
+ */
+ if (likely(len >= 7)) {
+ len -= (4 - (int)buff) & 3;
+ count = len >> 2;
+ asm (
+ " sub.4 d15, #0, %2 \n\t" // set up for jump table
+ " and.4 d15, #(32-1), d15 \n\t" // d15 = (-m) & (32 - 1)
+
+ " bfextu d14, %0, #2 \n\t" // test 2 LSB of buff
+ " jmpne.w.f 100f \n\t"
+ " add.4 %1, #0, %1 \n\t" // clear C
+ " moveai a3, #%%hi(1f) \n\t" // table jump
+ " lea.1 a3, %%lo(1f)(a3) \n\t"
+ " lea.4 a3, (a3,d15) \n\t"
+ " calli a3, 0(a3) \n\t"
+
+ "100: sub.4 %0, %0, d14 \n\t"
+ " sub.4 d14, #4, d14 \n\t"
+ " lsl.4 d14, d14, #3 \n\t"
+ " add.4 %1, #0, %1 \n\t" // clear C
+ " moveai a3, #%%hi(1f) \n\t" // table jump
+ " lea.1 a3, %%lo(1f)(a3) \n\t"
+ " lea.4 a3, (a3,d15) \n\t"
+ " bfextu %1, (%0)4++, d14 \n\t" // read first partial word
+ " calli a3, 0(a3) \n\t"
+#if 1
+ "200: lsl.4 %3, %3, #3 \n\t"
+ " bfrvrs d15, (%0), #0 \n\t" // read last word (partial)
+ " bfextu d15, d15, %3 \n\t"
+ " bfrvrs d15, d15, #0 \n\t"
+ " add.4 %1, d15, %1 \n\t"
+ " addc %1, #0, %1 \n\t" // sample C again
+ " jmpt.w.t 2f \n\t"
+#else
+ "200: move.1 d15, 0(%0) \n\t"
+ " lsl.4 d15, d15, #8 \n\t"
+ " add.4 %1, d15, %1 \n\t"
+ " addc %1, #0, %1 \n\t" // sample C again
+ " add.4 %3, #-1, %3 \n\t"
+ " jmpeq.w.t 2f \n\t"
+
+ " move.1 d15, 1(%0) \n\t"
+ " add.4 %1, d15, %1 \n\t"
+ " addc %1, #0, %1 \n\t" // sample C again
+ " add.4 %3, #-1, %3 \n\t"
+ " jmpeq.w.t 2f \n\t"
+
+ " move.1 d15, 2(%0) \n\t"
+ " lsl.4 d15, d15, #8 \n\t"
+ " add.4 %1, d15, %1 \n\t"
+ " addc %1, #0, %1 \n\t" // sample C again
+ " jmpt.w.t 2f \n\t"
+#endif
+#if defined(IP7000) || defined(IP7000_REV2)
+ "300: swapb.2 %1, %1 \n\t"
+#else
+ "300: shmrg.2 %1, %1, %1 \n\t"
+ " lsr.4 %1, %1, #8 \n\t"
+ " bfextu %1, %1, #16 \n\t"
+#endif
+ " jmpt.w.t 3f \n\t"
+
+ "1: add.4 %1, (%0)4++, %1 \n\t" // first add without C
+ " .rept 31 \n\t"
+ " addc %1, (%0)4++, %1 \n\t"
+ " .endr \n\t"
+ " addc %1, #0, %1 \n\t" // sample C again
+ " add.4 %2, #-32, %2 \n\t"
+ " jmpgt.w.t 1b \n\t"
+
+ " and.4 %3, #3, %3 \n\t" // check n
+ " jmpne.w.f 200b \n\t"
+
+ "2: .rept 2 \n\t"
+ " lsr.4 d15, %1, #16 \n\t"
+ " bfextu %1, %1, #16 \n\t"
+ " add.4 %1, d15, %1 \n\t"
+ " .endr \n\t"
+ " btst d14, #3 \n\t" // start from odd address (<< 3)?
+ " jmpne.w.f 300b \n\t"
+ "3: \n\t"
+
+ : "+a"(buff), "+d"(result), "+d"(count), "+d"(len)
+ :
+ : "d15", "d14", "a3", "cc"
+ );
+
+ return result;
+ }
+
+ /*
+ * handle a few bytes and fold result into 16-bit
+ */
+ while (len-- > 0) {
+ result += (*buff++ << 8);
+ if (len) {
+ result += *buff++;
+ len--;
+ }
+ }
+ asm (
+ " .rept 2 \n\t"
+ " lsr.4 d15, %0, #16 \n\t"
+ " bfextu %0, %0, #16 \n\t"
+ " add.4 %0, d15, %0 \n\t"
+ " .endr \n\t"
+ : "+d" (result)
+ :
+ : "d15", "cc"
+ );
+
+ return result;
+}
+
+/*
+ * This is a version of ip_compute_csum() optimized for IP headers,
+ * which always checksum on 4 octet boundaries.
+ */
+__sum16 ip_fast_csum(const void *iph, unsigned int ihl)
+{
+ return (__force __sum16)~do_csum(iph,ihl*4);
+}
+
+/*
+ * 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)
+{
+ unsigned int result = do_csum(buff, len);
+
+ /* add in old sum, and carry.. */
+ result += (__force u32)sum;
+ if ((__force u32)sum > result)
+ result += 1;
+ return (__force __wsum)result;
+}
+
+EXPORT_SYMBOL(csum_partial);
+
+/*
+ * this routine is used for miscellaneous IP-like checksums, mainly
+ * in icmp.c
+ */
+__sum16 ip_compute_csum(const void *buff, int len)
+{
+ return (__force __sum16)~do_csum(buff,len);
+}
+
+/*
+ * copy from fs while checksumming, otherwise like csum_partial
+ */
+
+__wsum
+csum_partial_copy_from_user(const void __user *src, void *dst,
+ int len, __wsum sum, int *csum_err)
+{
+ if (csum_err) *csum_err = 0;
+ memcpy(dst, (__force const void *)src, len);
+ return csum_partial(dst, len, sum);
+}
+
+/*
+ * copy from ds while checksumming, otherwise like csum_partial
+ */
+
+__wsum
+csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum)
+{
+ memcpy(dst, src, len);
+ return csum_partial(dst, len, sum);
+}
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