[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/arch/parisc/lib/checksum.c b/src/kernel/linux/v4.14/arch/parisc/lib/checksum.c
new file mode 100644
index 0000000..ba6384d
--- /dev/null
+++ b/src/kernel/linux/v4.14/arch/parisc/lib/checksum.c
@@ -0,0 +1,149 @@
+/*
+ * 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.
+ *
+ * MIPS specific IP/TCP/UDP checksumming routines
+ *
+ * Authors: Ralf Baechle, <ralf@waldorf-gmbh.de>
+ * Lots of code moved from tcp.c and ip.c; see those files
+ * for more names.
+ *
+ * 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.
+ */
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include <net/checksum.h>
+#include <asm/byteorder.h>
+#include <asm/string.h>
+#include <linux/uaccess.h>
+
+#define addc(_t,_r) \
+ __asm__ __volatile__ ( \
+" add %0, %1, %0\n" \
+" addc %0, %%r0, %0\n" \
+ : "=r"(_t) \
+ : "r"(_r), "0"(_t));
+
+static inline unsigned short from32to16(unsigned int x)
+{
+ /* 32 bits --> 16 bits + carry */
+ x = (x & 0xffff) + (x >> 16);
+ /* 16 bits + carry --> 16 bits including carry */
+ x = (x & 0xffff) + (x >> 16);
+ return (unsigned short)x;
+}
+
+static inline unsigned int do_csum(const unsigned char * buff, int len)
+{
+ int odd, count;
+ unsigned int result = 0;
+
+ if (len <= 0)
+ goto out;
+ odd = 1 & (unsigned long) buff;
+ if (odd) {
+ result = be16_to_cpu(*buff);
+ len--;
+ buff++;
+ }
+ count = len >> 1; /* nr of 16-bit words.. */
+ if (count) {
+ if (2 & (unsigned long) buff) {
+ result += *(unsigned short *) buff;
+ count--;
+ len -= 2;
+ buff += 2;
+ }
+ count >>= 1; /* nr of 32-bit words.. */
+ if (count) {
+ while (count >= 4) {
+ unsigned int r1, r2, r3, r4;
+ r1 = *(unsigned int *)(buff + 0);
+ r2 = *(unsigned int *)(buff + 4);
+ r3 = *(unsigned int *)(buff + 8);
+ r4 = *(unsigned int *)(buff + 12);
+ addc(result, r1);
+ addc(result, r2);
+ addc(result, r3);
+ addc(result, r4);
+ count -= 4;
+ buff += 16;
+ }
+ while (count) {
+ unsigned int w = *(unsigned int *) buff;
+ count--;
+ buff += 4;
+ addc(result, w);
+ }
+ result = (result & 0xffff) + (result >> 16);
+ }
+ if (len & 2) {
+ result += *(unsigned short *) buff;
+ buff += 2;
+ }
+ }
+ if (len & 1)
+ result += le16_to_cpu(*buff);
+ result = from32to16(result);
+ if (odd)
+ result = swab16(result);
+out:
+ return result;
+}
+
+/*
+ * computes a partial checksum, e.g. for TCP/UDP fragments
+ */
+/*
+ * why bother folding?
+ */
+__wsum csum_partial(const void *buff, int len, __wsum sum)
+{
+ unsigned int result = do_csum(buff, len);
+ addc(result, sum);
+ return (__force __wsum)from32to16(result);
+}
+
+EXPORT_SYMBOL(csum_partial);
+
+/*
+ * copy while checksumming, otherwise like csum_partial
+ */
+__wsum csum_partial_copy_nocheck(const void *src, void *dst,
+ int len, __wsum sum)
+{
+ /*
+ * It's 2:30 am and I don't feel like doing it real ...
+ * This is lots slower than the real thing (tm)
+ */
+ sum = csum_partial(src, len, sum);
+ memcpy(dst, src, len);
+
+ return sum;
+}
+EXPORT_SYMBOL(csum_partial_copy_nocheck);
+
+/*
+ * Copy from userspace and compute checksum. If we catch an exception
+ * then zero the rest of the buffer.
+ */
+__wsum csum_partial_copy_from_user(const void __user *src,
+ void *dst, int len,
+ __wsum sum, int *err_ptr)
+{
+ int missing;
+
+ missing = copy_from_user(dst, src, len);
+ if (missing) {
+ memset(dst + len - missing, 0, missing);
+ *err_ptr = -EFAULT;
+ }
+
+ return csum_partial(dst, len, sum);
+}
+EXPORT_SYMBOL(csum_partial_copy_from_user);