enet.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

		break;
		
#ifndef final_version
	/* Since we have allocated space to hold a complete frame, both
	 * the first and last indicators should be set.
	 */
	if ((bdp->cbd_sc & (BD_ENET_RX_FIRST | BD_ENET_RX_LAST)) !=
		(BD_ENET_RX_FIRST | BD_ENET_RX_LAST))
			printk("CPM ENET: rcv is not first+last\n");
#endif

	/* Frame too long or too short.
	*/
	if (bdp->cbd_sc & (BD_ENET_RX_LG | BD_ENET_RX_SH))
		cep->stats.rx_length_errors++;
	if (bdp->cbd_sc & BD_ENET_RX_NO)	/* Frame alignment */
		cep->stats.rx_frame_errors++;
	if (bdp->cbd_sc & BD_ENET_RX_CR)	/* CRC Error */
		cep->stats.rx_crc_errors++;
	if (bdp->cbd_sc & BD_ENET_RX_OV)	/* FIFO overrun */
		cep->stats.rx_crc_errors++;

	/* Report late collisions as a frame error.
	 * On this error, the BD is closed, but we don't know what we
	 * have in the buffer.  So, just drop this frame on the floor.
	 */
	if (bdp->cbd_sc & BD_ENET_RX_CL) {
		cep->stats.rx_frame_errors++;
	}
	else {

		/* Process the incoming frame.
		*/
		cep->stats.rx_packets++;
		pkt_len = bdp->cbd_datlen;
		cep->stats.rx_bytes += pkt_len;

		/* This does 16 byte alignment, much more than we need.
		 * The packet length includes FCS, but we don't want to
		 * include that when passing upstream as it messes up
		 * bridging applications.
		 */
		skb = dev_alloc_skb(pkt_len-4);

		if (skb == NULL) {
			printk("%s: Memory squeeze, dropping packet.\n", dev->name);
			cep->stats.rx_dropped++;
		}
		else {
			skb->dev = dev;
			skb_put(skb,pkt_len-4);	/* Make room */
			eth_copy_and_sum(skb,
				(unsigned char *)__va(bdp->cbd_bufaddr),
				pkt_len-4, 0);
			skb->protocol=eth_type_trans(skb,dev);
			netif_rx(skb);
		}
	}

	/* Clear the status flags for this buffer.
	*/
	bdp->cbd_sc &= ~BD_ENET_RX_STATS;

	/* Mark the buffer empty.
	*/
	bdp->cbd_sc |= BD_ENET_RX_EMPTY;

	/* Update BD pointer to next entry.
	*/
	if (bdp->cbd_sc & BD_ENET_RX_WRAP)
		bdp = cep->rx_bd_base;
	else
		bdp++;

   }
	cep->cur_rx = (cbd_t *)bdp;

	return 0;
}

static int
scc_enet_close(struct net_device *dev)
{
	/* Don't know what to do yet.
	*/
	netif_stop_queue(dev);

	return 0;
}

static struct net_device_stats *scc_enet_get_stats(struct net_device *dev)
{
	struct scc_enet_private *cep = (struct scc_enet_private *)dev->priv;

	return &cep->stats;
}

/* Set or clear the multicast filter for this adaptor.
 * Skeleton taken from sunlance driver.
 * The CPM Ethernet implementation allows Multicast as well as individual
 * MAC address filtering.  Some of the drivers check to make sure it is
 * a group multicast address, and discard those that are not.  I guess I
 * will do the same for now, but just remove the test if you want
 * individual filtering as well (do the upper net layers want or support
 * this kind of feature?).
 */

static void set_multicast_list(struct net_device *dev)
{
	struct	scc_enet_private *cep;
	struct	dev_mc_list *dmi;
	u_char	*mcptr, *tdptr;
	volatile scc_enet_t *ep;
	int	i, j;
	cep = (struct scc_enet_private *)dev->priv;

	/* Get pointer to SCC area in parameter RAM.
	*/
	ep = (scc_enet_t *)dev->base_addr;

	if (dev->flags&IFF_PROMISC) {
	  
		/* Log any net taps. */
		printk("%s: Promiscuous mode enabled.\n", dev->name);
		cep->sccp->scc_pmsr |= SCC_PSMR_PRO;
	} else {

		cep->sccp->scc_pmsr &= ~SCC_PSMR_PRO;

		if (dev->flags & IFF_ALLMULTI) {
			/* Catch all multicast addresses, so set the
			 * filter to all 1's.
			 */
			ep->sen_gaddr1 = 0xffff;
			ep->sen_gaddr2 = 0xffff;
			ep->sen_gaddr3 = 0xffff;
			ep->sen_gaddr4 = 0xffff;
		}
		else {
			/* Clear filter and add the addresses in the list.
			*/
			ep->sen_gaddr1 = 0;
			ep->sen_gaddr2 = 0;
			ep->sen_gaddr3 = 0;
			ep->sen_gaddr4 = 0;

			dmi = dev->mc_list;

			for (i=0; i<dev->mc_count; i++) {
				
				/* Only support group multicast for now.
				*/
				if (!(dmi->dmi_addr[0] & 1))
					continue;

				/* The address in dmi_addr is LSB first,
				 * and taddr is MSB first.  We have to
				 * copy bytes MSB first from dmi_addr.
				 */
				mcptr = (u_char *)dmi->dmi_addr + 5;
				tdptr = (u_char *)&ep->sen_taddrh;
				for (j=0; j<6; j++)
					*tdptr++ = *mcptr--;

				/* Ask CPM to run CRC and set bit in
				 * filter mask.
				 */
				cpmp->cp_cpcr = mk_cr_cmd(CPM_ENET_PAGE,
						CPM_ENET_BLOCK, 0,
						CPM_CR_SET_GADDR) | CPM_CR_FLG;
				/* this delay is necessary here -- Cort */
				udelay(10);
				while (cpmp->cp_cpcr & CPM_CR_FLG);
			}
		}
	}
}

/* Initialize the CPM Ethernet on SCC.
 */
int __init scc_enet_init(void)
{
	struct net_device *dev;
	struct scc_enet_private *cep;
	int i, j;
	unsigned char	*eap;
	unsigned long	mem_addr;
	bd_t		*bd;
	volatile	cbd_t		*bdp;
	volatile	cpm8260_t	*cp;
	volatile	scc_t		*sccp;
	volatile	scc_enet_t	*ep;
	volatile	immap_t		*immap;
	volatile	iop8260_t	*io;

	cp = cpmp;	/* Get pointer to Communication Processor */

	immap = (immap_t *)IMAP_ADDR;	/* and to internal registers */
	io = &immap->im_ioport;

	bd = (bd_t *)__res;

	/* Allocate some private information.
	*/
	cep = (struct scc_enet_private *)kmalloc(sizeof(*cep), GFP_KERNEL);
	if (cep == NULL)
		return -ENOMEM;

	__clear_user(cep,sizeof(*cep));
	spin_lock_init(&cep->lock);

	/* Create an Ethernet device instance.
	*/
	dev = init_etherdev(0, 0);

	/* Get pointer to SCC area in parameter RAM.
	*/
	ep = (scc_enet_t *)(&immap->im_dprambase[PROFF_ENET]);

	/* And another to the SCC register area.
	*/
	sccp = (volatile scc_t *)(&immap->im_scc[SCC_ENET]);
	cep->sccp = (scc_t *)sccp;		/* Keep the pointer handy */

	/* Disable receive and transmit in case someone left it running.
	*/
	sccp->scc_gsmrl &= ~(SCC_GSMRL_ENR | SCC_GSMRL_ENT);

	/* Configure port C and D pins for SCC Ethernet.  This
	 * won't work for all SCC possibilities....it will be
	 * board/port specific.
	 */
	io->iop_pparc |=
		(PC_ENET_RENA | PC_ENET_CLSN | PC_ENET_TXCLK | PC_ENET_RXCLK);
	io->iop_pdirc &=
		~(PC_ENET_RENA | PC_ENET_CLSN | PC_ENET_TXCLK | PC_ENET_RXCLK);
	io->iop_psorc &= 
		~(PC_ENET_RENA | PC_ENET_TXCLK | PC_ENET_RXCLK);
	io->iop_psorc |= PC_ENET_CLSN;

	io->iop_ppard |= (PD_ENET_RXD | PD_ENET_TXD | PD_ENET_TENA);
	io->iop_pdird |= (PD_ENET_TXD | PD_ENET_TENA);
	io->iop_pdird &= ~PD_ENET_RXD;
	io->iop_psord |= PD_ENET_TXD;
	io->iop_psord &= ~(PD_ENET_RXD | PD_ENET_TENA);

	/* Configure Serial Interface clock routing.
	 * First, clear all SCC bits to zero, then set the ones we want.
	 */
	immap->im_cpmux.cmx_scr &= ~CMX_CLK_MASK;
	immap->im_cpmux.cmx_scr |= CMX_CLK_ROUTE;

	/* Allocate space for the buffer descriptors in the DP ram.
	 * These are relative offsets in the DP ram address space.
	 * Initialize base addresses for the buffer descriptors.
	 */
	i = m8260_cpm_dpalloc(sizeof(cbd_t) * RX_RING_SIZE, 8);
	ep->sen_genscc.scc_rbase = i;
	cep->rx_bd_base = (cbd_t *)&immap->im_dprambase[i];

	i = m8260_cpm_dpalloc(sizeof(cbd_t) * TX_RING_SIZE, 8);
	ep->sen_genscc.scc_tbase = i;
	cep->tx_bd_base = (cbd_t *)&immap->im_dprambase[i];

	cep->dirty_tx = cep->cur_tx = cep->tx_bd_base;
	cep->cur_rx = cep->rx_bd_base;

	ep->sen_genscc.scc_rfcr = CPMFCR_GBL | CPMFCR_EB;
	ep->sen_genscc.scc_tfcr = CPMFCR_GBL | CPMFCR_EB;

	/* Set maximum bytes per receive buffer.
	 * This appears to be an Ethernet frame size, not the buffer
	 * fragment size.  It must be a multiple of four.
	 */
	ep->sen_genscc.scc_mrblr = PKT_MAXBLR_SIZE;

	/* Set CRC preset and mask.
	*/
	ep->sen_cpres = 0xffffffff;
	ep->sen_cmask = 0xdebb20e3;

	ep->sen_crcec = 0;	/* CRC Error counter */
	ep->sen_alec = 0;	/* alignment error counter */
	ep->sen_disfc = 0;	/* discard frame counter */

	ep->sen_pads = 0x8888;	/* Tx short frame pad character */
	ep->sen_retlim = 15;	/* Retry limit threshold */

	ep->sen_maxflr = PKT_MAXBUF_SIZE;   /* maximum frame length register */
	ep->sen_minflr = PKT_MINBUF_SIZE;  /* minimum frame length register */

	ep->sen_maxd1 = PKT_MAXBLR_SIZE;	/* maximum DMA1 length */
	ep->sen_maxd2 = PKT_MAXBLR_SIZE;	/* maximum DMA2 length */

	/* Clear hash tables.
	*/
	ep->sen_gaddr1 = 0;
	ep->sen_gaddr2 = 0;
	ep->sen_gaddr3 = 0;
	ep->sen_gaddr4 = 0;
	ep->sen_iaddr1 = 0;
	ep->sen_iaddr2 = 0;
	ep->sen_iaddr3 = 0;
	ep->sen_iaddr4 = 0;

	/* Set Ethernet station address.
	 *
	 * This is supplied in the board information structure, so we
	 * copy that into the controller.
	 */
	eap = (unsigned char *)&(ep->sen_paddrh);
	for (i=5; i>=0; i--)
		*eap++ = dev->dev_addr[i] = bd->bi_enetaddr[i];

	ep->sen_pper = 0;	/* 'cause the book says so */
	ep->sen_taddrl = 0;	/* temp address (LSB) */
	ep->sen_taddrm = 0;
	ep->sen_taddrh = 0;	/* temp address (MSB) */

	/* Now allocate the host memory pages and initialize the
	 * buffer descriptors.
	 */
	bdp = cep->tx_bd_base;
	for (i=0; i<TX_RING_SIZE; i++) {

		/* Initialize the BD for every fragment in the page.
		*/
		bdp->cbd_sc = 0;
		bdp->cbd_bufaddr = 0;
		bdp++;
	}

	/* Set the last buffer to wrap.
	*/
	bdp--;
	bdp->cbd_sc |= BD_SC_WRAP;

	bdp = cep->rx_bd_base;
	for (i=0; i<CPM_ENET_RX_PAGES; i++) {

		/* Allocate a page.
		*/
		mem_addr = __get_free_page(GFP_KERNEL);

		/* Initialize the BD for every fragment in the page.
		*/
		for (j=0; j<CPM_ENET_RX_FRPPG; j++) {
			bdp->cbd_sc = BD_ENET_RX_EMPTY | BD_ENET_RX_INTR;
			bdp->cbd_bufaddr = __pa(mem_addr);
			mem_addr += CPM_ENET_RX_FRSIZE;
			bdp++;
		}
	}

	/* Set the last buffer to wrap.
	*/
	bdp--;
	bdp->cbd_sc |= BD_SC_WRAP;

	/* Let's re-initialize the channel now.  We have to do it later
	 * than the manual describes because we have just now finished
	 * the BD initialization.
	 */
	cpmp->cp_cpcr = mk_cr_cmd(CPM_ENET_PAGE, CPM_ENET_BLOCK, 0,
			CPM_CR_INIT_TRX) | CPM_CR_FLG;
	while (cp->cp_cpcr & CPM_CR_FLG);

	cep->skb_cur = cep->skb_dirty = 0;

	sccp->scc_scce = 0xffff;	/* Clear any pending events */

	/* Enable interrupts for transmit error, complete frame
	 * received, and any transmit buffer we have also set the
	 * interrupt flag.
	 */
	sccp->scc_sccm = (SCCE_ENET_TXE | SCCE_ENET_RXF | SCCE_ENET_TXB);

	/* Install our interrupt handler.
	*/
	request_8xxirq(SIU_INT_ENET, scc_enet_interrupt, 0, "enet", dev);

	/* Set GSMR_H to enable all normal operating modes.
	 * Set GSMR_L to enable Ethernet to MC68160.
	 */
	sccp->scc_gsmrh = 0;
	sccp->scc_gsmrl = (SCC_GSMRL_TCI | SCC_GSMRL_TPL_48 | SCC_GSMRL_TPP_10 | SCC_GSMRL_MODE_ENET);

	/* Set sync/delimiters.
	*/
	sccp->scc_dsr = 0xd555;

	/* Set processing mode.  Use Ethernet CRC, catch broadcast, and
	 * start frame search 22 bit times after RENA.
	 */
	sccp->scc_pmsr = (SCC_PSMR_ENCRC | SCC_PSMR_NIB22);

	/* It is now OK to enable the Ethernet transmitter.
	 * Unfortunately, there are board implementation differences here.
	 */
	io->iop_pparc &= ~(PC_EST8260_ENET_LOOPBACK |
				PC_EST8260_ENET_SQE | PC_EST8260_ENET_NOTFD);
	io->iop_psorc &= ~(PC_EST8260_ENET_LOOPBACK |
				PC_EST8260_ENET_SQE | PC_EST8260_ENET_NOTFD);
	io->iop_pdirc |= (PC_EST8260_ENET_LOOPBACK |
				PC_EST8260_ENET_SQE | PC_EST8260_ENET_NOTFD);
	io->iop_pdatc &= ~(PC_EST8260_ENET_LOOPBACK | PC_EST8260_ENET_SQE);
	io->iop_pdatc |= PC_EST8260_ENET_NOTFD;

	dev->base_addr = (unsigned long)ep;
	dev->priv = cep;

	/* The CPM Ethernet specific entries in the device structure. */
	dev->open = scc_enet_open;
	dev->hard_start_xmit = scc_enet_start_xmit;
	dev->tx_timeout = scc_enet_timeout;
	dev->watchdog_timeo = TX_TIMEOUT;
	dev->stop = scc_enet_close;
	dev->get_stats = scc_enet_get_stats;
	dev->set_multicast_list = set_multicast_list;

	/* And last, enable the transmit and receive processing.
	*/
	sccp->scc_gsmrl |= (SCC_GSMRL_ENR | SCC_GSMRL_ENT);

	printk("%s: SCC ENET Version 0.1, ", dev->name);
	for (i=0; i<5; i++)
		printk("%02x:", dev->dev_addr[i]);
	printk("%02x\n", dev->dev_addr[5]);

	return 0;
}