if_ln.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

	struct ln_softc *sc;
{
	/*
	 * NOTE: do not change the order of these
	 * register declarations due to asm() instruction
	 * used below.
	 */
	register unsigned long *tbl_addr;	/* initialization table addr */
	register int inicrc;			/* initial CRC */
	register int len;			/* length of multicast addr */
	register struct ln_multi *multi_addr;	/* multicast address, 48 bits */
	register int *ln_crc = &sc->ln_crc;

	/* initialize polynomial table, only done once from lnprobe() */

	if (lnshowmulti) {
		printf("addr=%x.%x.%x.%x.%x.%x, ",
			(struct ln_multi *)addr->ln_multi_char[0],
			(struct ln_multi *)addr->ln_multi_char[1],
			(struct ln_multi *)addr->ln_multi_char[2],
			(struct ln_multi *)addr->ln_multi_char[3],
			(struct ln_multi *)addr->ln_multi_char[4],
			(struct ln_multi *)addr->ln_multi_char[5]);
	}

	/* initialize arguments */
	tbl_addr = ln_crc_table;
	inicrc = -1;
	len = 6;
	multi_addr = addr;

#ifdef lint
	tbl_addr = tbl_addr;
	inicrc = inicrc;
	len = len;
	multi_addr = multi_addr;
#endif

#ifdef vax
	/* calculate CRC */
	asm( "crc	(r11),r10,r9,(r8)" );
	asm( "movl	r0, (r7)" );
#else 
	/* Need to calculate CRC */
	*ln_crc = crc256(multi_addr, len);
#endif vax 

	return(0);
}


int  crctbl[256] = {
	0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
	0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 
	0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 
	0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 
	0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 
	0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 
	0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, 
	0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
	0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
	0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
	0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
	0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
	0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
	0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
	0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
	0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
	0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
	0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
	0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
	0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
	0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
	0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
	0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
	0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
	0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
	0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
	0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
	0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
	0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
	0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
	0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
	0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D };

crc256(addr, len)
u_char *addr;
int len;
{
	register unsigned int crc;

	crc = (u_long)0xffffffffL;
	while(len--)
                crc = (crc >> 8) ^ crctbl[*addr++] ^ crctbl[crc&0xff];

	return(crc);
}


/*
 * Restart the Lance chip -- this routine is called:
 *   - after changing the multicast address filter mask
 *   - on any loopback mode state change
 *   - on any error which disables the transmitter
 *   - on all missed packet errors
 *
 * The routine first halts the Lance chip, clears any previously
 * allcated mbufs, and then re-initializes the hardware (same as in
 * lnprobe() routine).  The lninit() routine is usually called next
 * to reallocate mbufs for the receive ring, and then actually
 * start the chip running again.
 */
lnrestart( ifp )
	register struct ifnet *ifp;
{
	register struct ln_softc *sc = ln_softc[ifp->if_unit];
	register char *initb = sc->initbaddr;
	register int i, pi;
	int s;

	/*
	 * stop the chip
	 */
        s = splimp();
        smp_lock(&sc->lk_ln_softc, LK_RETRY);

	/* disable DMA before setting STOP bit in case a DMA transaction
	 * had been started.
	 */
	if (sc->lnsw->ln_dma) {
	    *(u_int *)(sc->ssraddr) &= ~BIT16SET;
	}
	sc->ln_rap = LN_CSR0;
	sc->ln_rdp = LN_STOP;

	/* renable DMA in I/O ASIC */
	if (sc->lnsw->ln_dma) {
	    *(u_int *)(sc->ssraddr) |= BIT16SET;
	}

	/*
	 * stop network activity
	 */
	ifp->if_flags &= ~IFF_RUNNING;
	lnrestarts++;

	if (lndebug)
		mprintf("lnrestart: restarted ln%d  %d\n",ifp->if_unit,lnrestarts);

	/*
	 * free up any mbufs currently in use
	 */
	for (i=0; i<nLNNXMT; i++) {
		if (sc->tmbuf[i])
			m_freem(sc->tmbuf[i]);
		sc->tmbuf[i] = (struct mbuf *)NULL;
	}

	if ( sc->lnsw->ln_dodma ) {
	/*
	 * free up any mbufs currently in use
	 */
		for (i=0; i<nLNNRCV; i++) {
			if (sc->rmbuf[i])
				m_freem(sc->rmbuf[i]);
			sc->rmbuf[i] = (struct mbuf *)NULL;
		}
	}

	/*
	 * reload Lance with init block
	 */
	sc->lnsw->ln_cpyout(&sc->ln_initb,initb,sizeof(struct ln_initb),0);
	sc->ln_rap = LN_CSR1;
	pi = sc->lnsw->ln_svtolance(initb);
	sc->ln_rdp = (short)(pi & 0xffff);
	sc->ln_rap = LN_CSR2;
	sc->ln_rdp = (short)(((int)pi>>16) & 0xff);

	/*
	 * clear IDON, and INIT the chip
	 */
	sc->ln_rap = LN_CSR0;
	sc->ln_rdp = (LN_IDON | LN_INIT | LN_INEA);

        smp_unlock(&sc->lk_ln_softc);

	i = 0;
	while (i++ < 100) {
		if ((sc->ln_rdp & LN_IDON) != 0) {
			break;
		}
		DELAY(10000);
	}
        smp_lock(&sc->lk_ln_softc, LK_RETRY);

	/* make sure got out okay */
	if ((sc->ln_rdp & LN_IDON) == 0) {
		if (sc->ln_rdp & LN_ERR)
			mprintf("lnrestart: initialization ln%d ERR csr0=%04x\n",
				ifp->if_unit,(sc->ln_rdp & 0xffff));
		else
			mprintf("lnrestart: cannot initialize ln%d\n",ifp->if_unit);
	}

	if (sc->lnsw->ln_dma) {
	    *(u_int *)(sc->ssraddr) &= ~BIT16SET;
	}
	/* set STOP to clear INIT and IDON */
	sc->ln_rdp = LN_STOP;

	if (sc->lnsw->ln_dma) {
	    *(u_int *)(sc->ssraddr) |= BIT16SET;
	}
        smp_unlock(&sc->lk_ln_softc);
        splx(s);

	return(0);
}

/*
 * Initialize a ring descriptor. Tie the buffer pointed to by
 * "dp" to the descriptor.
 */
lninitdesc (sc, desc, buf, option)
	register struct ln_softc *sc;
	register struct ln_ring *desc;
	register char **buf;
	int option;
{
	register int dp;		/* data pointer */
	register struct lnsw *lnsw = sc->lnsw;
	struct ln_ring *ring = &sc->ln_ring;

	/*
	 * clear the entire descriptor
	 */
	lnsw->ln_bzero(desc, sizeof(struct ln_ring));

	/*
	 * Perform the necessary allocation/deallocation
	 */
	if (option == LNALLOC) {
		*buf = lnsw->ln_allocb (sc, LN_BUF_SIZE, 0);
		if ( *buf == 0 ) {
			if (lndebug)
			    printf("ln: can't alloc space for buffers\n");
			return(-1);
		}
	}
	dp = lnsw->ln_svtolance(*buf);
					/* +4 for CRC */
	ring->ln_flag = 0;
	ring->ln_flag2 =0;
	ring->ln_buf_len = -(ETHERMTU + sizeof(struct ether_header) + 4);
	ring->ln_addr_lo = (short)dp & 0xffff;
	ring->ln_addr_hi =
		(short)(((int)dp >> 16) & 0xff);
	lnsw->ln_cpyout(ring,desc,sizeof(struct ln_ring),0);
	return(0);
}
/*
 * Initialize a ring descriptor for architectures which provide DMA.
 * 
 */
lninitdesc_dma (sc, desc, buf, option, index )
	register struct ln_softc *sc;
	register struct ln_ring *desc;
	register char **buf;
	int option, index;
{
	register struct lnsw *lnsw = sc->lnsw;
        register struct mbuf *m=0, *p;
        int dp, dp1;                /* data pointer */
	struct ln_ring *ring = &sc->ln_ring;


	/*
	 * clear the entire descriptor
	 */
	lnsw->ln_bzero(desc, sizeof(struct ln_ring));

	/*
	 * Perform the necessary allocation/deallocation
	 */
	if (option == LNALLOC) {
		*buf = lnsw->ln_allocb(sc, LN_BUF_SIZE, 0);
		if ( *buf == 0 ) {
			if (lndebug)
			    printf("ln: can't alloc space for buffers\n");
			return(-1);
		}
	}

	/* only for dma receive side */
	MGET(m, M_DONTWAIT, MT_DATA);
       	if ( m ) {
        	MCLGET(m,p);
       		if ( p ) {
			dp  = svtophy(mtod(m,caddr_t));
			dp1 = svtophy(mtod(m,caddr_t)+LN_BUF_SIZE); 

      			/* check for physical continguous & less than 16M */
     			if (!(dp1 & 0xff000000 ) && ((dp1 - dp) == LN_BUF_SIZE )) {
        			sc->dma[index]=1;
				m->m_off += 2; 
				dp = dp+2;
        		} else {
               			dp = svtophy((caddr_t)sc->rlbuf[index]);
        			sc->dma[index]=0;
       			}
			/* For both DMA and Non-DMA */
        		sc->rmbuf[index]=m;
		} else {
   			if (lndebug)
              			printf("ln: no mbuf clusters\n");
               		m_freem(m);
               		sc->rmbuf[index] = 0;
               		dp = svtophy((caddr_t)sc->rlbuf[index]);
        		sc->dma[index]=0;
		}	
	} else {
               	if (lndebug)
        		printf("ln: no mbuf\n");
               	sc->rmbuf[index] = 0;
               	dp = svtophy((caddr_t)sc->rlbuf[index]);
        	sc->dma[index]=0;
	}
					
	desc->ln_flag = 0;
	desc->ln_flag2 =0;
	desc->ln_buf_len = -(ETHERMTU + sizeof(struct ether_header) + 4);
	desc->ln_addr_lo = (short)dp & 0xffff;
	desc->ln_addr_hi =
		(short)(((int)dp >> 16) & 0xff);
	return(0);
}
/*
 * Put an mbuf chain into the appropriate RAM buffer.
 */
lnput(sc, index, m)
	struct ln_softc *sc;
	int index;
	register struct mbuf *m;
{
	register caddr_t dp;
	register caddr_t lrbptr = sc->tlbuf[index];
	register struct lnsw *lnsw = sc->lnsw;
	int len = 0;

	sc->tmbuf[index] = m;	/* mbuf chain to free on xmit */
	while (m) {
		if (m->m_len == 0)
			goto next_m;
		dp = mtod(m, char *);
		lrbptr = lnsw->ln_cpyoutb(dp,lrbptr,(unsigned)m->m_len,0);
next_m:	
		len += m->m_len;
		m = m->m_next;
	}

	if (len < MINDATA) {
                lnsw->ln_bzerob(lrbptr, MINDATA - len);
		len = MINDATA;
	}
	return (len);
}

/*
 * Pull read data off an interface. (For DMA architectures).
 * Len is length of data, with local net header stripped.
 * Off is non-zero if a trailer protocol was used, and
 * gives the offset of the trailer information.
 * We first copy all the normal data into a cluster then deal 
 * with trailer.
 */
struct mbuf *
lnget_dma(sc,rlbuf, totlen, off0,index)
	struct ln_softc *sc ;
	register caddr_t rlbuf;
	int totlen,index,off0;
{
        register caddr_t lrbptr,dp;
	register int dma = sc->dma[index] ; 
        register struct lnsw *lnsw = sc->lnsw;
        struct mbuf *top, **mp, *m=0;
        int off = off0, len, tlen=0;

        top = 0;
        mp = &top;

        if (dma)
                lrbptr=rlbuf=mtod(sc->rmbuf[index],caddr_t);
        else
                lrbptr=rlbuf;

	while (totlen > 0) {
                len = totlen;
                if ( off ) {
                        MGET(m, M_DONTWAIT, MT_DATA);
			if (m == 0) {
                                m_freem(top);
                                return (0);
                                }
			len = totlen - off;
			lrbptr = rlbuf + off;
                } else {
                        /* if non dma use the mbuf we already allocated */
			if ( !dma ) {
                        	m=sc->rmbuf[index];
                        	m->m_len = len;
                       		 goto copy;
                        }
		}
nopage:
                m->m_len = MIN(MLEN, len);
                m->m_off = MMINOFF;
copy:
		lrbptr = lnsw->ln_cpyinb(sc, lrbptr,
				mtod(m, caddr_t),(unsigned)m->m_len,0);
next_m:
                *mp = m;
                mp = &m->m_next;
                if (off) {
                        off += m->m_len;
                        if (off == totlen) {
                                lrbptr = rlbuf;
                                off = 0;
                                if ( dma ) {
                                        *mp = sc->rmbuf[index];
                                        (*mp)->m_len=off0;
                                        totlen = 0;
                                } else
                                        totlen = off0;
                        }
                } else
                        totlen -= m->m_len;
        }
        return (top);
}

/*
 * Pull read data off an interface.
 * Len is length of data, with local net header stripped.
 * Off is non-zero if a trailer protocol was used, and
 * gives the offset of the trailer information.
 * We first copy all the normal data into a cluster then deal 
 * with trailer.
 */
struct mbuf *
lnget(sc,rlbuf, totlen, off, index)
	struct ln_softc *sc;
	caddr_t rlbuf;
	int totlen,index;
	register int off;
{
	struct mbuf *top, **mp, *m, *tp=0;
	int len;
	register caddr_t lrbptr = rlbuf;
	register struct lnsw *lnsw = sc->lnsw;

	top = 0;
	mp = &top;
	
	if (off) {
		struct mbuf *pp;

		MGET(tp, M_DONTWAIT, MT_DATA);
		if (tp == 0) {
			return (0);
		}

		MCLGET(tp, pp);
		if (pp == 0)
			return (0);
		tp->m_len = off;
		lrbptr = lnsw->ln_cpyinb(sc, lrbptr,mtod(tp,caddr_t),(unsigned)off,0);
		totlen -= off;