tsec.c

 * hash index which gaddr register to use, and the 5 other bits
 * indicate which bit (assuming an IBM numbering scheme, which
 * for PowerPC (tm) is usually the case) in the tregister holds
 * the entry. */
static int
tsec_mcast_addr (struct eth_device *dev, u8 mcast_mac, u8 set)
{
	struct tsec_private *priv = privlist[1];
	volatile tsec_t *regs = priv->regs;
	volatile u32  *reg_array, value;
	u8 result, whichbit, whichreg;

	result = (u8)((ether_crc(MAC_ADDR_LEN,mcast_mac) >> 24) & 0xff);
	whichbit = result & 0x1f;	/* the 5 LSB = which bit to set */
	whichreg = result >> 5;		/* the 3 MSB = which reg to set it in */
	value = (1 << (31-whichbit));

	reg_array = &(regs->hash.gaddr0);

	if (set) {
		reg_array[whichreg] |= value;
	} else {
		reg_array[whichreg] &= ~value;
	}
	return 0;
}
#endif /* Multicast TFTP ? */