Commit 446ebd01 authored by Patrice Vilchez's avatar Patrice Vilchez Committed by Jeff Garzik
Browse files

macb: Add multicast capability 



Add multicast capability to Atmel ethernet macb driver.

Signed-off-by: default avatarPatrice Vilchez <patrice.vilchez@rfo.atmel.com>
Signed-off-by: default avatarHaavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 6c36a707

drivers/net/macb.c

+120 −0
Original line number Diff line number Diff line
@@ -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;