[netdrvr] ethernet crc fixes

* ether_crc has always been wrong in 2.5.x. ug. we want
  bitreverse crc32_le instead
* use ether_crc in natsemi

1 files changed, 11 insertions, 1 deletions

diff --git a/include/linux/crc32.h b/include/linux/crc32.h
index a0033ffee91c..56c0645789a9 100644
--- a/include/linux/crc32.h
+++ b/include/linux/crc32.h
@@ -9,9 +9,19 @@
 
 extern u32  crc32_le(u32 crc, unsigned char const *p, size_t len);
 extern u32  crc32_be(u32 crc, unsigned char const *p, size_t len);
+extern u32  bitreverse(u32 in);
 
 #define crc32(seed, data, length)  crc32_le(seed, (unsigned char const *)data, length)
+
+/*
+ * Helpers for hash table generation of ethernet nics:
+ *
+ * Ethernet sends the least significant bit of a byte first, thus crc32_le
+ * is used. The output of crc32_le is bit reversed [most significant bit
+ * is in bit nr 0], thus it must be reversed before use. Except for
+ * nics that bit swap the result internally...
+ */
+#define ether_crc(length, data)    bitreverse(crc32_le(~0, data, length))
 #define ether_crc_le(length, data) crc32_le(~0, data, length)
-#define ether_crc(length, data)    crc32_be(~0, data, length)
 
 #endif /* _LINUX_CRC32_H */