[PATCH v3] net: ethernet: freescale: Use generic CRC32 implementation

[PATCH v3] net: ethernet: freescale: Use generic CRC32 implementation

[Krzysztof Kozlowski]

Use generic kernel CRC32 implementation because it:
1. Should be faster (uses lookup tables),
2. Removes duplicated CRC generation code,
3. Uses well-proven algorithm instead of coding it one more time.

Suggested-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

---

Changes since v2:
1. Use ether_crc_le (suggested by David)

Changes since v1:
1. Fix missing header inclusion.
---
 drivers/net/ethernet/freescale/fec_main.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index c729665107f5..98ad34192255 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -48,6 +48,7 @@
 #include <linux/io.h>
 #include <linux/irq.h>
 #include <linux/clk.h>
+#include <linux/crc32.h>
 #include <linux/platform_device.h>
 #include <linux/mdio.h>
 #include <linux/phy.h>
@@ -2955,7 +2956,7 @@ static void set_multicast_list(struct net_device *ndev)
 {
 	struct fec_enet_private *fep = netdev_priv(ndev);
 	struct netdev_hw_addr *ha;
-	unsigned int i, bit, data, crc, tmp;
+	unsigned int crc, tmp;
 	unsigned char hash;
 	unsigned int hash_high = 0, hash_low = 0;
 
@@ -2983,15 +2984,7 @@ static void set_multicast_list(struct net_device *ndev)
 	/* Add the addresses in hash register */
 	netdev_for_each_mc_addr(ha, ndev) {
 		/* calculate crc32 value of mac address */
-		crc = 0xffffffff;
-
-		for (i = 0; i < ndev->addr_len; i++) {
-			data = ha->addr[i];
-			for (bit = 0; bit < 8; bit++, data >>= 1) {
-				crc = (crc >> 1) ^
-				(((crc ^ data) & 1) ? CRC32_POLY : 0);
-			}
-		}
+		crc = ether_crc_le(ndev->addr_len, ha->addr);
 
 		/* only upper 6 bits (FEC_HASH_BITS) are used
 		 * which point to specific bit in the hash registers
-- 
2.14.1

Re: [PATCH v3] net: ethernet: freescale: Use generic CRC32 implementation

[David Miller]

From: Krzysztof Kozlowski <krzk@kernel.org>
Date: Mon, 23 Jul 2018 18:19:14 +0200

> Use generic kernel CRC32 implementation because it:
> 1. Should be faster (uses lookup tables),
> 2. Removes duplicated CRC generation code,
> 3. Uses well-proven algorithm instead of coding it one more time.
> 
> Suggested-by: Eric Biggers <ebiggers3@gmail.com>
> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

Applied.