[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

drivers/net/natsemi.c

@@ -164,6 +164,7 @@
 #include <linux/delay.h>
 #include <linux/rtnetlink.h>
 #include <linux/mii.h>
+#include <linux/crc32.h>
 #include <asm/processor.h>	/* Processor type for cache alignment. */
 #include <asm/bitops.h>
 #include <asm/io.h>
@@ -1898,44 +1899,6 @@ static struct net_device_stats *get_stats(struct net_device *dev)
 	return &np->stats;
 }
 
-/**
- * dp83815_crc - computer CRC for hash table entries
- *
- * Note - this is, for some reason, *not* the same function
- * as ether_crc_le() or ether_crc(), though it uses the
- * same big-endian polynomial.
- */
-#define DP_POLYNOMIAL			0x04C11DB7
-static unsigned dp83815_crc(int length, unsigned char *data)
-{
-	u32 crc;
-	u8 cur_byte;
-	u8 msb;
-	u8 byte, bit;
-
-	crc = ~0;
-	for (byte=0; byte<length; byte++) {
-		cur_byte = *data++;
-		for (bit=0; bit<8; bit++) {
-			msb = crc >> 31;
-			crc <<= 1;
-			if (msb ^ (cur_byte & 1)) {
-				crc ^= DP_POLYNOMIAL;
-				crc |= 1;
-			}
-			cur_byte >>= 1;
-		}
-	}
-	crc >>= 23;
-
-	return (crc);
-}
-
-
-void set_bit_le(int offset, unsigned char * data)
-{
-	data[offset >> 3] |= (1 << (offset & 0x07));
-}
 #define HASH_TABLE	0x200
 static void __set_rx_mode(struct net_device *dev)
 {
@@ -1960,9 +1923,8 @@ static void __set_rx_mode(struct net_device *dev)
 		memset(mc_filter, 0, sizeof(mc_filter));
 		for (i = 0, mclist = dev->mc_list; mclist && i < dev->mc_count;
 			 i++, mclist = mclist->next) {
-			set_bit_le(
-				dp83815_crc(ETH_ALEN, mclist->dmi_addr) & 0x1ff,
-				mc_filter);
+			int i = (ether_crc(ETH_ALEN, mclist->dmi_addr) >> 23) & 0x1ff;
+			mc_filter[i/8] |= (1 << (i & 0x07));
 		}
 		rx_mode = RxFilterEnable | AcceptBroadcast
 			| AcceptMulticast | AcceptMyPhys;

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 */

lib/crc32.c

@@ -265,8 +265,19 @@ u32 attribute((pure)) crc32_be(u32 crc, unsigned char const *p, size_t len)
 }
 #endif
 
+u32 bitreverse(u32 x)
+{
+	x = (x >> 16) | (x << 16);
+	x = (x >> 8 & 0x00ff00ff) | (x << 8 & 0xff00ff00);
+	x = (x >> 4 & 0x0f0f0f0f) | (x << 4 & 0xf0f0f0f0);
+	x = (x >> 2 & 0x33333333) | (x << 2 & 0xcccccccc);
+	x = (x >> 1 & 0x55555555) | (x << 1 & 0xaaaaaaaa);
+	return x;
+}
+
 EXPORT_SYMBOL(crc32_le);
 EXPORT_SYMBOL(crc32_be);
+EXPORT_SYMBOL(bitreverse);
 
 /*
  * A brief CRC tutorial.
@@ -412,16 +423,6 @@ buf_dump(char const *prefix, unsigned char const *buf, size_t len)
 }
 #endif
 
-static u32 attribute((const)) bitreverse(u32 x)
-{
-	x = (x >> 16) | (x << 16);
-	x = (x >> 8 & 0x00ff00ff) | (x << 8 & 0xff00ff00);
-	x = (x >> 4 & 0x0f0f0f0f) | (x << 4 & 0xf0f0f0f0);
-	x = (x >> 2 & 0x33333333) | (x << 2 & 0xcccccccc);
-	x = (x >> 1 & 0x55555555) | (x << 1 & 0xaaaaaaaa);
-	return x;
-}
-
 static void bytereverse(unsigned char *buf, size_t len)
 {
 	while (len--) {