fec.c

讲述linux的初始化过程

	}
	else
		fec_stop(dev);

#if 0
	enable_irq(fep->mii_irq);
#endif

}

static void mii_queue_relink(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep = dev->priv;

	fep->phy_task.routine = (void *)mii_relink;
	fep->phy_task.data = dev;
	schedule_task(&fep->phy_task);
}

static void mii_queue_config(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep = dev->priv;

	fep->phy_task.routine = (void *)mii_display_config;
	fep->phy_task.data = dev;
	schedule_task(&fep->phy_task);
}



phy_cmd_t phy_cmd_relink[] = { { mk_mii_read(MII_REG_CR), mii_queue_relink },
			       { mk_mii_end, } };
phy_cmd_t phy_cmd_config[] = { { mk_mii_read(MII_REG_CR), mii_queue_config },
			       { mk_mii_end, } };



/* Read remainder of PHY ID.
*/
static void
mii_discover_phy3(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep;
	int	i;

	fep = dev->priv;
	fep->phy_id |= (mii_reg & 0xffff);
	printk("fec: Phy @ 0x%x, type 0x%08x\n", fep->phy_addr, fep->phy_id);

	for(i = 0; phy_info[i]; i++)
		if(phy_info[i]->id == (fep->phy_id >> 4))
			break;

	if(!phy_info[i])
		panic("%s: PHY id 0x%08x is not supported!\n", 
		      dev->name, fep->phy_id);
      
	fep->phy = phy_info[i];
	fep->phy_id_done = 1;
}

/* Scan all of the MII PHY addresses looking for someone to respond
 * with a valid ID.  This usually happens quickly.
 */
static void
mii_discover_phy(uint mii_reg, struct net_device *dev)
{
	struct fec_enet_private *fep;
	uint	phytype;

	fep = dev->priv;

	if (fep->phy_addr < 32) {
		if ((phytype = (mii_reg & 0xffff)) != 0xffff) {
			
			/* Got first part of ID, now get remainder.
			*/
			fep->phy_id = phytype << 16;
			mii_queue(dev, mk_mii_read(MII_REG_PHYIR2),
							mii_discover_phy3);
		}
		else {
			fep->phy_addr++;
			mii_queue(dev, mk_mii_read(MII_REG_PHYIR1),
							mii_discover_phy);
		}
	}
	else {
		printk("FEC: No PHY device found.\n");
	}
}

/* This interrupt occurs when the PHY detects a link change.
*/
static void
#ifdef CONFIG_RPXCLASSIC
mii_link_interrupt(void *dev_id)
#else
mii_link_interrupt(int irq, void * dev_id, struct pt_regs * regs)
#endif
{
	struct	net_device *dev = dev_id;
	struct fec_enet_private *fep = dev->priv;

#if 0
	disable_irq(fep->mii_irq);  /* disable now, enable later */
#endif

	mii_do_cmd(dev, fep->phy->ack_int);
	mii_do_cmd(dev, phy_cmd_relink);  /* restart and display status */

}

static int
fec_enet_open(struct net_device *dev)
{
	struct fec_enet_private *fep = dev->priv;

	/* I should reset the ring buffers here, but I don't yet know
	 * a simple way to do that.
	 */

	fep->sequence_done = 0;
	fep->link = 0;

	if (fep->phy) {
		mii_do_cmd(dev, fep->phy->ack_int);
		mii_do_cmd(dev, fep->phy->config);
		mii_do_cmd(dev, phy_cmd_config);  /* display configuration */

		while(!fep->sequence_done)
			schedule();

		mii_do_cmd(dev, fep->phy->startup);
		netif_start_queue(dev);
		return 0;		/* Success */
	}

	return -ENODEV;		/* No PHY we understand */

}

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

	return 0;
}

static struct net_device_stats *fec_enet_get_stats(struct net_device *dev)
{
	struct fec_enet_private *fep = (struct fec_enet_private *)dev->priv;

	return &fep->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	fec_enet_private *fep;
	volatile fec_t *ep;

	fep = (struct fec_enet_private *)dev->priv;
	ep = &(((immap_t *)IMAP_ADDR)->im_cpm.cp_fec);

	if (dev->flags&IFF_PROMISC) {
	  
		/* Log any net taps. */
		printk("%s: Promiscuous mode enabled.\n", dev->name);
		ep->fec_r_cntrl |= 0x0008;
	} else {

		ep->fec_r_cntrl &= ~0x0008;

		if (dev->flags & IFF_ALLMULTI) {
			/* Catch all multicast addresses, so set the
			 * filter to all 1's.
			 */
			ep->fec_hash_table_high = 0xffffffff;
			ep->fec_hash_table_low = 0xffffffff;
		}
#if 0
		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_CR_CH_SCC1, CPM_CR_SET_GADDR) | CPM_CR_FLG;
				/* this delay is necessary here -- Cort */
				udelay(10);
				while (cpmp->cp_cpcr & CPM_CR_FLG);
			}
		}
#endif
	}
}

/* Initialize the FEC Ethernet on 860T.
 */
int __init fec_enet_init(void)
{
	struct net_device *dev;
	struct fec_enet_private *fep;
	int i, j;
	unsigned char	*eap, *iap;
	unsigned long	mem_addr;
	pte_t		*pte;
	volatile	cbd_t	*bdp;
	cbd_t		*cbd_base;
	volatile	immap_t	*immap;
	volatile	fec_t	*fecp;
	bd_t		*bd;
	extern		uint	_get_IMMR(void);
#ifdef CONFIG_RPXCLASSIC
	unsigned char	tmpaddr[6];
#endif

	immap = (immap_t *)IMAP_ADDR;	/* pointer to internal registers */

	bd = (bd_t *)__res;

	/* Allocate some private information.
	*/
	fep = (struct fec_enet_private *)kmalloc(sizeof(*fep), GFP_KERNEL);
	__clear_user(fep,sizeof(*fep));

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

	fecp = &(immap->im_cpm.cp_fec);

	/* Whack a reset.  We should wait for this.
	*/
	fecp->fec_ecntrl = 1;
	udelay(10);

	/* Set the Ethernet address.  If using multiple Enets on the 8xx,
	 * this needs some work to get unique addresses.
	 */
	eap = (unsigned char *)my_enet_addr;
	iap = bd->bi_enetaddr;

#ifdef CONFIG_RPXCLASSIC
	/* The Embedded Planet boards have only one MAC address in
	 * the EEPROM, but can have two Ethernet ports.  For the
	 * FEC port, we create another address by setting one of
	 * the address bits above something that would have (up to
	 * now) been allocated.
	 */
	for (i=0; i<6; i++)
		tmpaddr[i] = *iap++;
	tmpaddr[3] |= 0x80;
	iap = tmpaddr;
#endif

	for (i=0; i<6; i++)
		dev->dev_addr[i] = *eap++ = *iap++;

	/* Allocate memory for buffer descriptors.
	*/
	if (((RX_RING_SIZE + TX_RING_SIZE) * sizeof(cbd_t)) > PAGE_SIZE) {
		printk("FEC init error.  Need more space.\n");
		printk("FEC initialization failed.\n");
		return 1;
	}
	mem_addr = __get_free_page(GFP_KERNEL);
	cbd_base = (cbd_t *)mem_addr;

	/* Make it uncached.
	*/
	pte = va_to_pte(mem_addr);
	pte_val(*pte) |= _PAGE_NO_CACHE;
	flush_tlb_page(init_mm.mmap, mem_addr);

	/* Set receive and transmit descriptor base.
	*/
	fep->rx_bd_base = cbd_base;
	fep->tx_bd_base = cbd_base + RX_RING_SIZE;

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

	fep->skb_cur = fep->skb_dirty = 0;

	/* Initialize the receive buffer descriptors.
	*/
	bdp = fep->rx_bd_base;
	for (i=0; i<FEC_ENET_RX_PAGES; i++) {

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

		/* Make it uncached.
		*/
		pte = va_to_pte(mem_addr);
		pte_val(*pte) |= _PAGE_NO_CACHE;
		flush_tlb_page(init_mm.mmap, mem_addr);

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

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

#ifdef CONFIG_FEC_PACKETHOOK
	fep->ph_lock = 0;
	fep->ph_rxhandler = fep->ph_txhandler = NULL;
	fep->ph_proto = 0;
	fep->ph_regaddr = NULL;
	fep->ph_priv = NULL;
#endif

	/* Install our interrupt handler.
	*/
	if (request_8xxirq(FEC_INTERRUPT, fec_enet_interrupt, 0, "fec", dev) != 0)
		panic("Could not allocate FEC IRQ!");
#ifdef CONFIG_RPXCLASSIC
	/* Make Port C, bit 15 an input that causes interrupts.
	*/
	immap->im_ioport.iop_pcpar &= ~0x0001;
	immap->im_ioport.iop_pcdir &= ~0x0001;
	immap->im_ioport.iop_pcso &= ~0x0001;
	immap->im_ioport.iop_pcint |= 0x0001;
	cpm_install_handler(CPMVEC_PIO_PC15, mii_link_interrupt, dev);

	/* Make LEDS reflect Link status.
	*/
	*((uint *) RPX_CSR_ADDR) &= ~BCSR2_FETHLEDMODE;
#endif
#ifdef CONFIG_FADS
	if (request_8xxirq(SIU_IRQ2, mii_link_interrupt, 0, "mii", dev) != 0)
		panic("Could not allocate MII IRQ!");
#endif

	dev->base_addr = (unsigned long)fecp;
	dev->priv = fep;

	/* The FEC Ethernet specific entries in the device structure. */
	dev->open = fec_enet_open;
	dev->hard_start_xmit = fec_enet_start_xmit;
	dev->tx_timeout = fec_timeout;
	dev->watchdog_timeo = TX_TIMEOUT;
	dev->stop = fec_enet_close;
	dev->get_stats = fec_enet_get_stats;
	dev->set_multicast_list = set_multicast_list;

	for (i=0; i<NMII-1; i++)
		mii_cmds[i].mii_next = &mii_cmds[i+1];
	mii_free = mii_cmds;

	/* Configure all of port D for MII.
	*/
	immap->im_ioport.iop_pdpar = 0x1fff;

	/* Bits moved from Rev. D onward.
	*/
	if ((_get_IMMR() & 0xffff) < 0x0501)
		immap->im_ioport.iop_pddir = 0x1c58;	/* Pre rev. D */
	else
		immap->im_ioport.iop_pddir = 0x1fff;	/* Rev. D and later */
	
	/* Set MII speed to 2.5 MHz
	*/
	fecp->fec_mii_speed = fep->phy_speed = 
		((bd->bi_busfreq * 1000000) / 2500000) & 0x7e;

	printk("%s: FEC ENET Version 0.2, ", dev->name);
	for (i=0; i<5; i++)
		printk("%02x:", dev->dev_addr[i]);
	printk("%02x\n", dev->dev_addr[5]);

	/* Queue up command to detect the PHY and initialize the
	 * remainder of the interface.
	 */
	fep->phy_id_done = 0;
	fep->phy_addr = 0;
	mii_queue(dev, mk_mii_read(MII_REG_PHYIR1), mii_discover_phy);

	return 0;
}

/* This function is called to start or restart the FEC during a link
 * change.  This only happens when switching between half and full
 * duplex.
 */
static void
fec_restart(struct net_device *dev, int duplex)
{
	struct fec_enet_private *fep;
	int i;
	unsigned char	*eap;
	volatile	cbd_t	*bdp;
	volatile	immap_t	*immap;
	volatile	fec_t	*fecp;

	immap = (immap_t *)IMAP_ADDR;	/* pointer to internal registers */

	fecp = &(immap->im_cpm.cp_fec);

	fep = dev->priv;

	/* Whack a reset.  We should wait for this.
	*/
	fecp->fec_ecntrl = 1;
	udelay(10);

	/* Enable interrupts we wish to service.
	*/
	fecp->fec_imask = (FEC_ENET_TXF | FEC_ENET_TXB |
				FEC_ENET_RXF | FEC_ENET_RXB | FEC_ENET_MII);

	/* Clear any outstanding interrupt.
	*/
	fecp->fec_ievent = 0xffc0;

	fecp->fec_ivec = (FEC_INTERRUPT/2) << 29;

	/* Set station address.
	*/
	fecp->fec_addr_low = (my_enet_addr[0] << 16) | my_enet_addr[1];
	fecp->fec_addr_high = my_enet_addr[2];

	eap = (unsigned char *)&my_enet_addr[0];
	for (i=0; i<6; i++)
		dev->dev_addr[i] = *eap++;

	/* Reset all multicast.
	*/
	fecp->fec_hash_table_high = 0;
	fecp->fec_hash_table_low = 0;

	/* Set maximum receive buffer size.
	*/
	fecp->fec_r_buff_size = PKT_MAXBLR_SIZE;
	fecp->fec_r_hash = PKT_MAXBUF_SIZE;

	/* Set receive and transmit descriptor base.
	*/
	fecp->fec_r_des_start = __pa((uint)(fep->rx_bd_base));
	fecp->fec_x_des_start = __pa((uint)(fep->tx_bd_base));

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

	/* Reset SKB transmit buffers.
	*/
	fep->skb_cur = fep->skb_dirty = 0;
	for (i=0; i<=TX_RING_MOD_MASK; i++) {
		if (fep->tx_skbuff[i] != NULL) {
			dev_kfree_skb(fep->tx_skbuff[i]);
			fep->tx_skbuff[i] = NULL;
		}
	}

	/* Initialize the receive buffer descriptors.
	*/
	bdp = fep->rx_bd_base;
	for (i=0; i<RX_RING_SIZE; i++) {

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

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

	/* ...and the same for transmmit.
	*/
	bdp = fep->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;

	/* Enable MII mode.
	*/
	if (duplex) {
		fecp->fec_r_cntrl = 0x04;	/* MII enable */
		fecp->fec_x_cntrl = 0x04;	/* FD enable */
	}
	else {
		fecp->fec_r_cntrl = 0x06;	/* MII enable|No Rcv on Xmit */
		fecp->fec_x_cntrl = 0x00;
	}
	fep->full_duplex = duplex;

	/* Enable big endian and don't care about SDMA FC.
	*/
	fecp->fec_fun_code = 0x78000000;

	/* Set MII speed.
	*/
	fecp->fec_mii_speed = fep->phy_speed;

	/* And last, enable the transmit and receive processing.
	*/
	fecp->fec_ecntrl = 6;
	fecp->fec_r_des_active = 0x01000000;
}

static void
fec_stop(struct net_device *dev)
{
	volatile	immap_t	*immap;
	volatile	fec_t	*fecp;
	struct fec_enet_private *fep;

	immap = (immap_t *)IMAP_ADDR;	/* pointer to internal registers */
	
	fecp = &(immap->im_cpm.cp_fec);
	
	fep = dev->priv;


	fecp->fec_x_cntrl = 0x01;	/* Graceful transmit stop */

	while(!(fecp->fec_ievent & 0x10000000));

	/* Whack a reset.  We should wait for this.
	*/
	fecp->fec_ecntrl = 1;
	udelay(10);

	/* Clear outstanding MII command interrupts.
	*/
	fecp->fec_ievent = FEC_ENET_MII;

	/* Enable MII command finihed interrupt 
	*/
	fecp->fec_ivec = (FEC_INTERRUPT/2) << 29;
	fecp->fec_imask = FEC_ENET_MII;

	/* Set MII speed.
	*/
	fecp->fec_mii_speed = fep->phy_speed;
}