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

From: Krzysztof Kozlowski
Date: Mon Jul 23 2018 - 12:19:43 EST


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@xxxxxxxxx>
Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>

---

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