diff options
author | Lennert Buytenhek <buytenh@wantstofly.org> | 2008-06-01 11:43:32 +0200 |
---|---|---|
committer | Lennert Buytenhek <buytenh@wantstofly.org> | 2008-06-12 08:40:33 +0200 |
commit | 69876569bbf3dfac567f47c619888c827cb87b30 (patch) | |
tree | 7605c046ba3c5be284c782d8b41496a89673f548 /drivers/net/mv643xx_eth.c | |
parent | 16820054773027a9be2e2b5e33eb2015d32deeaf (diff) | |
download | op-kernel-dev-69876569bbf3dfac567f47c619888c827cb87b30.zip op-kernel-dev-69876569bbf3dfac567f47c619888c827cb87b30.tar.gz |
mv643xx_eth: massively simplify multicast address crc8 computation
Replace the 70-line crc8 computation (used for multicast address
filtering tables) by a 5-line version.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Acked-by: Dale Farnsworth <dale@farnsworth.org>
Diffstat (limited to 'drivers/net/mv643xx_eth.c')
-rw-r--r-- | drivers/net/mv643xx_eth.c | 95 |
1 files changed, 21 insertions, 74 deletions
diff --git a/drivers/net/mv643xx_eth.c b/drivers/net/mv643xx_eth.c index cc93af0..84e6c41 100644 --- a/drivers/net/mv643xx_eth.c +++ b/drivers/net/mv643xx_eth.c @@ -1141,16 +1141,29 @@ static int mv643xx_eth_set_mac_address(struct net_device *dev, void *addr) return 0; } +static int addr_crc(unsigned char *addr) +{ + int crc = 0; + int i; + + for (i = 0; i < 6; i++) { + int j; + + crc = (crc ^ addr[i]) << 8; + for (j = 7; j >= 0; j--) { + if (crc & (0x100 << j)) + crc ^= 0x107 << j; + } + } + + return crc; +} + static void mc_addr(struct mv643xx_eth_private *mp, unsigned char *addr) { unsigned int port_num = mp->port_num; - unsigned int mac_h; - unsigned int mac_l; - unsigned char crc_result = 0; int table; - int mac_array[48]; - int crc[8]; - int i; + int crc; if ((addr[0] == 0x01) && (addr[1] == 0x00) && (addr[2] == 0x5E) && (addr[3] == 0x00) && (addr[4] == 0x00)) { @@ -1159,76 +1172,10 @@ static void mc_addr(struct mv643xx_eth_private *mp, unsigned char *addr) return; } - /* Calculate CRC-8 out of the given address */ - mac_h = (addr[0] << 8) | (addr[1]); - mac_l = (addr[2] << 24) | (addr[3] << 16) | - (addr[4] << 8) | (addr[5] << 0); - - for (i = 0; i < 32; i++) - mac_array[i] = (mac_l >> i) & 0x1; - for (i = 32; i < 48; i++) - mac_array[i] = (mac_h >> (i - 32)) & 0x1; - - crc[0] = mac_array[45] ^ mac_array[43] ^ mac_array[40] ^ mac_array[39] ^ - mac_array[35] ^ mac_array[34] ^ mac_array[31] ^ mac_array[30] ^ - mac_array[28] ^ mac_array[23] ^ mac_array[21] ^ mac_array[19] ^ - mac_array[18] ^ mac_array[16] ^ mac_array[14] ^ mac_array[12] ^ - mac_array[8] ^ mac_array[7] ^ mac_array[6] ^ mac_array[0]; - - crc[1] = mac_array[46] ^ mac_array[45] ^ mac_array[44] ^ mac_array[43] ^ - mac_array[41] ^ mac_array[39] ^ mac_array[36] ^ mac_array[34] ^ - mac_array[32] ^ mac_array[30] ^ mac_array[29] ^ mac_array[28] ^ - mac_array[24] ^ mac_array[23] ^ mac_array[22] ^ mac_array[21] ^ - mac_array[20] ^ mac_array[18] ^ mac_array[17] ^ mac_array[16] ^ - mac_array[15] ^ mac_array[14] ^ mac_array[13] ^ mac_array[12] ^ - mac_array[9] ^ mac_array[6] ^ mac_array[1] ^ mac_array[0]; - - crc[2] = mac_array[47] ^ mac_array[46] ^ mac_array[44] ^ mac_array[43] ^ - mac_array[42] ^ mac_array[39] ^ mac_array[37] ^ mac_array[34] ^ - mac_array[33] ^ mac_array[29] ^ mac_array[28] ^ mac_array[25] ^ - mac_array[24] ^ mac_array[22] ^ mac_array[17] ^ mac_array[15] ^ - mac_array[13] ^ mac_array[12] ^ mac_array[10] ^ mac_array[8] ^ - mac_array[6] ^ mac_array[2] ^ mac_array[1] ^ mac_array[0]; - - crc[3] = mac_array[47] ^ mac_array[45] ^ mac_array[44] ^ mac_array[43] ^ - mac_array[40] ^ mac_array[38] ^ mac_array[35] ^ mac_array[34] ^ - mac_array[30] ^ mac_array[29] ^ mac_array[26] ^ mac_array[25] ^ - mac_array[23] ^ mac_array[18] ^ mac_array[16] ^ mac_array[14] ^ - mac_array[13] ^ mac_array[11] ^ mac_array[9] ^ mac_array[7] ^ - mac_array[3] ^ mac_array[2] ^ mac_array[1]; - - crc[4] = mac_array[46] ^ mac_array[45] ^ mac_array[44] ^ mac_array[41] ^ - mac_array[39] ^ mac_array[36] ^ mac_array[35] ^ mac_array[31] ^ - mac_array[30] ^ mac_array[27] ^ mac_array[26] ^ mac_array[24] ^ - mac_array[19] ^ mac_array[17] ^ mac_array[15] ^ mac_array[14] ^ - mac_array[12] ^ mac_array[10] ^ mac_array[8] ^ mac_array[4] ^ - mac_array[3] ^ mac_array[2]; - - crc[5] = mac_array[47] ^ mac_array[46] ^ mac_array[45] ^ mac_array[42] ^ - mac_array[40] ^ mac_array[37] ^ mac_array[36] ^ mac_array[32] ^ - mac_array[31] ^ mac_array[28] ^ mac_array[27] ^ mac_array[25] ^ - mac_array[20] ^ mac_array[18] ^ mac_array[16] ^ mac_array[15] ^ - mac_array[13] ^ mac_array[11] ^ mac_array[9] ^ mac_array[5] ^ - mac_array[4] ^ mac_array[3]; - - crc[6] = mac_array[47] ^ mac_array[46] ^ mac_array[43] ^ mac_array[41] ^ - mac_array[38] ^ mac_array[37] ^ mac_array[33] ^ mac_array[32] ^ - mac_array[29] ^ mac_array[28] ^ mac_array[26] ^ mac_array[21] ^ - mac_array[19] ^ mac_array[17] ^ mac_array[16] ^ mac_array[14] ^ - mac_array[12] ^ mac_array[10] ^ mac_array[6] ^ mac_array[5] ^ - mac_array[4]; - - crc[7] = mac_array[47] ^ mac_array[44] ^ mac_array[42] ^ mac_array[39] ^ - mac_array[38] ^ mac_array[34] ^ mac_array[33] ^ mac_array[30] ^ - mac_array[29] ^ mac_array[27] ^ mac_array[22] ^ mac_array[20] ^ - mac_array[18] ^ mac_array[17] ^ mac_array[15] ^ mac_array[13] ^ - mac_array[11] ^ mac_array[7] ^ mac_array[6] ^ mac_array[5]; - - for (i = 0; i < 8; i++) - crc_result = crc_result | (crc[i] << i); + crc = addr_crc(addr); table = OTHER_MCAST_TABLE(port_num); - set_filter_table_entry(mp, table, crc_result); + set_filter_table_entry(mp, table, crc); } static void set_multicast_list(struct net_device *dev) |