From 446ebd0118d8e82791652bd17dd8db08ab993c0e Mon Sep 17 00:00:00 2001 From: Patrice Vilchez Date: Thu, 12 Jul 2007 19:07:25 +0200 Subject: macb: Add multicast capability Add multicast capability to Atmel ethernet macb driver. Signed-off-by: Patrice Vilchez Signed-off-by: Haavard Skinnemoen Signed-off-by: Jeff Garzik --- drivers/net/macb.c | 120 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) (limited to 'drivers/net/macb.c') diff --git a/drivers/net/macb.c b/drivers/net/macb.c index 83c35fd91e0f..a4bb0264180a 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -796,6 +796,125 @@ static void macb_init_hw(struct macb *bp) } +/* + * The hash address register is 64 bits long and takes up two + * locations in the memory map. The least significant bits are stored + * in EMAC_HSL and the most significant bits in EMAC_HSH. + * + * The unicast hash enable and the multicast hash enable bits in the + * network configuration register enable the reception of hash matched + * frames. The destination address is reduced to a 6 bit index into + * the 64 bit hash register using the following hash function. The + * hash function is an exclusive or of every sixth bit of the + * destination address. + * + * hi[5] = da[5] ^ da[11] ^ da[17] ^ da[23] ^ da[29] ^ da[35] ^ da[41] ^ da[47] + * hi[4] = da[4] ^ da[10] ^ da[16] ^ da[22] ^ da[28] ^ da[34] ^ da[40] ^ da[46] + * hi[3] = da[3] ^ da[09] ^ da[15] ^ da[21] ^ da[27] ^ da[33] ^ da[39] ^ da[45] + * hi[2] = da[2] ^ da[08] ^ da[14] ^ da[20] ^ da[26] ^ da[32] ^ da[38] ^ da[44] + * hi[1] = da[1] ^ da[07] ^ da[13] ^ da[19] ^ da[25] ^ da[31] ^ da[37] ^ da[43] + * hi[0] = da[0] ^ da[06] ^ da[12] ^ da[18] ^ da[24] ^ da[30] ^ da[36] ^ da[42] + * + * da[0] represents the least significant bit of the first byte + * received, that is, the multicast/unicast indicator, and da[47] + * represents the most significant bit of the last byte received. If + * the hash index, hi[n], points to a bit that is set in the hash + * register then the frame will be matched according to whether the + * frame is multicast or unicast. A multicast match will be signalled + * if the multicast hash enable bit is set, da[0] is 1 and the hash + * index points to a bit set in the hash register. A unicast match + * will be signalled if the unicast hash enable bit is set, da[0] is 0 + * and the hash index points to a bit set in the hash register. To + * receive all multicast frames, the hash register should be set with + * all ones and the multicast hash enable bit should be set in the + * network configuration register. + */ + +static inline int hash_bit_value(int bitnr, __u8 *addr) +{ + if (addr[bitnr / 8] & (1 << (bitnr % 8))) + return 1; + return 0; +} + +/* + * Return the hash index value for the specified address. + */ +static int hash_get_index(__u8 *addr) +{ + int i, j, bitval; + int hash_index = 0; + + for (j = 0; j < 6; j++) { + for (i = 0, bitval = 0; i < 8; i++) + bitval ^= hash_bit_value(i*6 + j, addr); + + hash_index |= (bitval << j); + } + + return hash_index; +} + +/* + * Add multicast addresses to the internal multicast-hash table. + */ +static void macb_sethashtable(struct net_device *dev) +{ + struct dev_mc_list *curr; + unsigned long mc_filter[2]; + unsigned int i, bitnr; + struct macb *bp = netdev_priv(dev); + + mc_filter[0] = mc_filter[1] = 0; + + curr = dev->mc_list; + for (i = 0; i < dev->mc_count; i++, curr = curr->next) { + if (!curr) break; /* unexpected end of list */ + + bitnr = hash_get_index(curr->dmi_addr); + mc_filter[bitnr >> 5] |= 1 << (bitnr & 31); + } + + macb_writel(bp, HRB, mc_filter[0]); + macb_writel(bp, HRT, mc_filter[1]); +} + +/* + * Enable/Disable promiscuous and multicast modes. + */ +static void macb_set_rx_mode(struct net_device *dev) +{ + unsigned long cfg; + struct macb *bp = netdev_priv(dev); + + cfg = macb_readl(bp, NCFGR); + + if (dev->flags & IFF_PROMISC) + /* Enable promiscuous mode */ + cfg |= MACB_BIT(CAF); + else if (dev->flags & (~IFF_PROMISC)) + /* Disable promiscuous mode */ + cfg &= ~MACB_BIT(CAF); + + if (dev->flags & IFF_ALLMULTI) { + /* Enable all multicast mode */ + macb_writel(bp, HRB, -1); + macb_writel(bp, HRT, -1); + cfg |= MACB_BIT(NCFGR_MTI); + } else if (dev->mc_count > 0) { + /* Enable specific multicasts */ + macb_sethashtable(dev); + cfg |= MACB_BIT(NCFGR_MTI); + } else if (dev->flags & (~IFF_ALLMULTI)) { + /* Disable all multicast mode */ + macb_writel(bp, HRB, 0); + macb_writel(bp, HRT, 0); + cfg &= ~MACB_BIT(NCFGR_MTI); + } + + macb_writel(bp, NCFGR, cfg); +} + static int macb_open(struct net_device *dev) { struct macb *bp = netdev_priv(dev); @@ -1025,6 +1144,7 @@ static int __devinit macb_probe(struct platform_device *pdev) dev->stop = macb_close; dev->hard_start_xmit = macb_start_xmit; dev->get_stats = macb_get_stats; + dev->set_multicast_list = macb_set_rx_mode; dev->do_ioctl = macb_ioctl; dev->poll = macb_poll; dev->weight = 64; -- cgit v1.2.3-59-g8ed1b