1 files changed, 29 insertions, 0 deletions

diff --git a/include/asm-cris/arch-v10/checksum.h b/include/asm-cris/arch-v10/checksum.h
new file mode 100644
index 000000000000..fde1d00aaa90
--- /dev/null
+++ b/include/asm-cris/arch-v10/checksum.h
@@ -0,0 +1,29 @@
+#ifndef _CRIS_ARCH_CHECKSUM_H
+#define _CRIS_ARCH_CHECKSUM_H
+
+/* Checksum some values used in TCP/UDP headers.
+ *
+ * The gain by doing this in asm is that C will not generate carry-additions
+ * for the 32-bit components of the checksum, so otherwise we would have had
+ * to split all of those into 16-bit components, then add.
+ */
+
+extern inline unsigned int
+csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
+                   unsigned short proto, unsigned int sum)
+{
+        int res;
+        __asm__ ("add.d %2, %0\n\t"
+                 "ax\n\t"
+                 "add.d %3, %0\n\t"
+                 "ax\n\t"
+                 "add.d %4, %0\n\t"
+                 "ax\n\t"
+                 "addq 0, %0\n"
+        : "=r" (res)
+        : "0" (sum), "r" (daddr), "r" (saddr), "r" ((ntohs(len) << 16) + (proto << 8)));
+
+        return res;
+}       
+
+#endif