fcc_enet.c

《嵌入式系统设计与实例开发实验教材二源码》Linux内核移植与编译实验

	volatile	immap_t		*immap;
	volatile	iop8260_t	*io;

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

	np = sizeof(fcc_ports) / sizeof(fcc_info_t);
	fip = fcc_ports;

	while (np-- > 0) {

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

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

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

		init_fcc_shutdown(fip, cep, immap);
		init_fcc_ioports(fip, io, immap);
		init_fcc_param(fip, dev, immap);

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

		/* The CPM Ethernet specific entries in the device
		 * structure.
		 */
		dev->open = fcc_enet_open;
		dev->hard_start_xmit = fcc_enet_start_xmit;
		dev->tx_timeout = fcc_enet_timeout;
		dev->watchdog_timeo = TX_TIMEOUT;
		dev->stop = fcc_enet_close;
		dev->get_stats = fcc_enet_get_stats;
		dev->set_multicast_list = set_multicast_list;

		init_fcc_startup(fip, dev);

		printk("%s: FCC 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]);

		/* This is just a hack for now that works only on the EST
		 * board, or anything else that has MDIO/CK configured.
		 * It is mainly to test the MII software clocking.
		 */
		mii_discover_phy_poll(fip);

		fip++;
	}

	return 0;
}

/* Make sure the device is shut down during initialization.
*/
static void __init
init_fcc_shutdown(fcc_info_t *fip, struct fcc_enet_private *cep,
						volatile immap_t *immap)
{
	volatile	fcc_enet_t	*ep;
	volatile	fcc_t		*fccp;

	/* Get pointer to FCC area in parameter RAM.
	*/
	ep = (fcc_enet_t *)(&immap->im_dprambase[fip->fc_proff]);

	/* And another to the FCC register area.
	*/
	fccp = (volatile fcc_t *)(&immap->im_fcc[fip->fc_fccnum]);
	cep->fccp = fccp;		/* Keep the pointers handy */
	cep->ep = ep;

	/* Disable receive and transmit in case someone left it running.
	*/
	fccp->fcc_gfmr &= ~(FCC_GFMR_ENR | FCC_GFMR_ENT);
}

/* Initialize the I/O pins for the FCC Ethernet.
*/
static void __init
init_fcc_ioports(fcc_info_t *fip, volatile iop8260_t *io,
						volatile immap_t *immap)
{

	/* FCC1 pins are on port A/C.  FCC2/3 are port B/C.
	*/
	if (fip->fc_proff == PROFF_FCC1) {
		/* Configure port A and C pins for FCC1 Ethernet.
		 */
		io->iop_pdira &= ~PA1_DIRA0;
		io->iop_pdira |= PA1_DIRA1;
		io->iop_psora &= ~PA1_PSORA0;
		io->iop_psora |= PA1_PSORA1;
		io->iop_ppara |= (PA1_DIRA0 | PA1_DIRA1);
	}
	if (fip->fc_proff == PROFF_FCC2) {
		/* Configure port B and C pins for FCC Ethernet.
		 */
		io->iop_pdirb &= ~PB2_DIRB0;
		io->iop_pdirb |= PB2_DIRB1;
		io->iop_psorb &= ~PB2_PSORB0;
		io->iop_psorb |= PB2_PSORB1;
		io->iop_pparb |= (PB2_DIRB0 | PB2_DIRB1);
	}
	if (fip->fc_proff == PROFF_FCC3) {
		/* Configure port B and C pins for FCC Ethernet.
		 */
		io->iop_pdirb &= ~PB3_DIRB0;
		io->iop_pdirb |= PB3_DIRB1;
		io->iop_psorb &= ~PB3_PSORB0;
		io->iop_psorb |= PB3_PSORB1;
		io->iop_pparb |= (PB3_DIRB0 | PB3_DIRB1);
	}

	/* Port C has clocks......
	*/
	io->iop_psorc &= ~(fip->fc_trxclocks);
	io->iop_pdirc &= ~(fip->fc_trxclocks);
	io->iop_pparc |= fip->fc_trxclocks;

	/* ....and the MII serial clock/data.
	*/
	io->iop_pdatc |= (fip->fc_mdio | fip->fc_mdck);
	io->iop_podrc |= fip->fc_mdio;
	io->iop_pdirc |= (fip->fc_mdio | fip->fc_mdck);
	io->iop_pparc &= ~(fip->fc_mdio | fip->fc_mdck);

	/* Configure Serial Interface clock routing.
	 * First, clear all FCC bits to zero,
	 * then set the ones we want.
	 */
	immap->im_cpmux.cmx_fcr &= ~(fip->fc_clockmask);
	immap->im_cpmux.cmx_fcr |= fip->fc_clockroute;
}

static void __init
init_fcc_param(fcc_info_t *fip, struct net_device *dev,
						volatile immap_t *immap)
{
	unsigned char	*eap;
	unsigned long	mem_addr;
	bd_t		*bd;
	int		i, j;
	struct		fcc_enet_private *cep;
	volatile	fcc_enet_t	*ep;
	volatile	cbd_t		*bdp;
	volatile	cpm8260_t	*cp;

	cep = (struct fcc_enet_private *)(dev->priv);
	ep = cep->ep;
	cp = cpmp;

	bd = (bd_t *)__res;

	/* Zero the whole thing.....I must have missed some individually.
	 * It works when I do this.
	 */
	memset((char *)ep, 0, sizeof(fcc_enet_t));

	/* 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.
	 */
#if 0
	/* I really want to do this, but for some reason it doesn't
	 * work with the data cache enabled, so I allocate from the
	 * main memory instead.
	 */
	i = m8260_cpm_dpalloc(sizeof(cbd_t) * RX_RING_SIZE, 8);
	ep->fen_genfcc.fcc_rbase = (uint)&immap->im_dprambase[i];
	cep->rx_bd_base = (cbd_t *)&immap->im_dprambase[i];

	i = m8260_cpm_dpalloc(sizeof(cbd_t) * TX_RING_SIZE, 8);
	ep->fen_genfcc.fcc_tbase = (uint)&immap->im_dprambase[i];
	cep->tx_bd_base = (cbd_t *)&immap->im_dprambase[i];
#else
	cep->rx_bd_base = (cbd_t *)m8260_cpm_hostalloc(sizeof(cbd_t) * RX_RING_SIZE, 8);
	ep->fen_genfcc.fcc_rbase = __pa(cep->rx_bd_base);
	cep->tx_bd_base = (cbd_t *)m8260_cpm_hostalloc(sizeof(cbd_t) * TX_RING_SIZE, 8);
	ep->fen_genfcc.fcc_tbase = __pa(cep->tx_bd_base);
#endif

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

	ep->fen_genfcc.fcc_rstate = (CPMFCR_GBL | CPMFCR_EB) << 24;
	ep->fen_genfcc.fcc_tstate = (CPMFCR_GBL | CPMFCR_EB) << 24;

	/* Set maximum bytes per receive buffer.
	 * It must be a multiple of 32.
	 */
	ep->fen_genfcc.fcc_mrblr = PKT_MAXBLR_SIZE;

	/* Allocate space in the reserved FCC area of DPRAM for the
	 * internal buffers.  No one uses this space (yet), so we
	 * can do this.  Later, we will add resource management for
	 * this area.
	 */
	mem_addr = CPM_FCC_SPECIAL_BASE + (fip->fc_fccnum * 128);
	ep->fen_genfcc.fcc_riptr = mem_addr;
	ep->fen_genfcc.fcc_tiptr = mem_addr+32;
	ep->fen_padptr = mem_addr+64;
	memset((char *)(&(immap->im_dprambase[(mem_addr+64)])), 0x88, 32);
	
	ep->fen_genfcc.fcc_rbptr = 0;
	ep->fen_genfcc.fcc_tbptr = 0;
	ep->fen_genfcc.fcc_rcrc = 0;
	ep->fen_genfcc.fcc_tcrc = 0;
	ep->fen_genfcc.fcc_res1 = 0;
	ep->fen_genfcc.fcc_res2 = 0;

	ep->fen_camptr = 0;	/* CAM isn't used in this driver */

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

	ep->fen_crcec = 0;	/* CRC Error counter */
	ep->fen_alec = 0;	/* alignment error counter */
	ep->fen_disfc = 0;	/* discard frame counter */
	ep->fen_retlim = 15;	/* Retry limit threshold */
	ep->fen_pper = 0;	/* Normal persistence */

	/* Clear hash filter tables.
	*/
	ep->fen_gaddrh = 0;
	ep->fen_gaddrl = 0;
	ep->fen_iaddrh = 0;
	ep->fen_iaddrl = 0;

	/* Clear the Out-of-sequence TxBD.
	*/
	ep->fen_tfcstat = 0;
	ep->fen_tfclen = 0;
	ep->fen_tfcptr = 0;

	ep->fen_mflr = PKT_MAXBUF_SIZE;   /* maximum frame length register */
	ep->fen_minflr = PKT_MINBUF_SIZE;  /* minimum frame length register */

	/* Set Ethernet station address.
	 *
	 * This is supplied in the board information structure, so we
	 * copy that into the controller.
	 * So, far we have only been given one Ethernet address. We make
	 * it unique by setting a few bits in the upper byte of the
	 * non-static part of the address.
	 */
	eap = (unsigned char *)&(ep->fen_paddrh);
	for (i=5; i>=0; i--) {
		if (i == 3) {
			dev->dev_addr[i] = bd->bi_enetaddr[i];
			dev->dev_addr[i] |= (1 << (7 - fip->fc_fccnum));
			*eap++ = dev->dev_addr[i];
		}
		else {
			*eap++ = dev->dev_addr[i] = bd->bi_enetaddr[i];
		}
	}

	ep->fen_taddrh = 0;
	ep->fen_taddrm = 0;
	ep->fen_taddrl = 0;

	ep->fen_maxd1 = PKT_MAXDMA_SIZE;	/* maximum DMA1 length */
	ep->fen_maxd2 = PKT_MAXDMA_SIZE;	/* maximum DMA2 length */

	/* Clear stat counters, in case we ever enable RMON.
	*/
	ep->fen_octc = 0;
	ep->fen_colc = 0;
	ep->fen_broc = 0;
	ep->fen_mulc = 0;
	ep->fen_uspc = 0;
	ep->fen_frgc = 0;
	ep->fen_ospc = 0;
	ep->fen_jbrc = 0;
	ep->fen_p64c = 0;
	ep->fen_p65c = 0;
	ep->fen_p128c = 0;
	ep->fen_p256c = 0;
	ep->fen_p512c = 0;
	ep->fen_p1024c = 0;

	ep->fen_rfthr = 0;	/* Suggested by manual */
	ep->fen_rfcnt = 0;
	ep->fen_cftype = 0;

	/* 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_datlen = 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<FCC_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<FCC_ENET_RX_FRPPG; j++) {
			bdp->cbd_sc = BD_ENET_RX_EMPTY | BD_ENET_RX_INTR;
			bdp->cbd_datlen = 0;
			bdp->cbd_bufaddr = __pa(mem_addr);
			mem_addr += FCC_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.
	 */
	cp->cp_cpcr = mk_cr_cmd(fip->fc_cpmpage, fip->fc_cpmblock, 0x0c,
			CPM_CR_INIT_TRX) | CPM_CR_FLG;
	while (cp->cp_cpcr & CPM_CR_FLG);

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

/* Let 'er rip.
*/
static void __init
init_fcc_startup(fcc_info_t *fip, struct net_device *dev)
{
	volatile fcc_t	*fccp;
	struct fcc_enet_private *cep;

	cep = (struct fcc_enet_private *)(dev->priv);
	fccp = cep->fccp;

	fccp->fcc_fcce = 0xffff;	/* Clear any pending events */

	/* Enable interrupts for transmit error, complete frame
	 * received, and any transmit buffer we have also set the
	 * interrupt flag.
	 */
	fccp->fcc_fccm = (FCC_ENET_TXE | FCC_ENET_RXF | FCC_ENET_TXB);

	/* Install our interrupt handler.
	*/
	if (request_8xxirq(fip->fc_interrupt, fcc_enet_interrupt, 0,
							"fenet", dev) < 0)
		printk("Can't get FCC IRQ %d\n", fip->fc_interrupt);

	/* Set GFMR to enable Ethernet operating mode.
	 */
	fccp->fcc_gfmr = (FCC_GFMR_TCI | FCC_GFMR_MODE_ENET);

	/* Set sync/delimiters.
	*/
	fccp->fcc_fdsr = 0xd555;

	/* Set protocol specific processing mode for Ethernet.
	 * This has to be adjusted for Full Duplex operation after we can
	 * determine how to detect that.
	 */
	fccp->fcc_fpsmr = FCC_PSMR_ENCRC;

	/* And last, enable the transmit and receive processing.
	*/
	fccp->fcc_gfmr |= (FCC_GFMR_ENR | FCC_GFMR_ENT);
}

/* MII command/status interface.
 * I'm not going to describe all of the details.  You can find the
 * protocol definition in many other places, including the data sheet
 * of most PHY parts.
 * I wonder what "they" were thinking (maybe weren't) when they leave
 * the I2C in the CPM but I have to toggle these bits......
 */
static uint
mii_send_receive(fcc_info_t *fip, uint cmd)
{
	unsigned long	flags;
	uint		retval;
	int		read_op, i;
	volatile	immap_t		*immap;
	volatile	iop8260_t	*io;

	immap = (immap_t *)IMAP_ADDR;
	io = &immap->im_ioport;

	/* When we get here, both clock and data are high, outputs.
	 * Output is open drain.
	 * Data transitions on high->low clock, is valid on low->high clock.
	 * Spec says edge transitions no closer than 160 nSec, minimum clock
	 * cycle 400 nSec.  I could only manage about 500 nSec edges with
	 * an XOR loop, so I won't worry about delays yet.
	 * I disable interrupts during bit flipping to ensure atomic
	 * updates of the registers.  I do lots of interrupt disable/enable
	 * to ensure we don't hang out too long with interrupts disabled.
	 */
	
	/* First, crank out 32 1-bits as preamble.
	 * This is 64 transitions to clock the bits, with clock/data
	 * left high.
	 */
	save_flags(flags);
	cli();
	for (i=0; i<64; i++) {
		io->iop_pdatc ^= fip->fc_mdck;
		udelay(0);
	}
	restore_flags(flags);

	read_op = ((cmd & 0xf0000000) == 0x60000000);

	/* We return the command word on a write op, or the command portion
	 * plus the new data on a read op.  This is what the 8xx FEC does,
	 * and it allows the functions to simply look at the returned value
	 * and know the PHY/register as well.
	 */
	if (read_op)
		retval = cmd;
	else
		retval = (cmd >> 16);

	/* Clock out the first 16 MS bits of the command.
	*/
	save_flags(flags);
	cli();
	for (i=0; i<16; i++) {
		io->iop_pdatc &= ~(fip->fc_mdck);
		if (cmd & 0x80000000)
			io->iop_pdatc |= fip->fc_mdio;
		else
			io->iop_pdatc &= ~(fip->fc_mdio);
		cmd <<= 1;
		io->iop_pdatc |= fip->fc_mdck;
		udelay(0);
	}

	/* Do the turn-around.  If read op, we make the IO and input.
	 * If write op, do the 1/0 thing.
	 */
	io->iop_pdatc &= ~(fip->fc_mdck);
	if (read_op)
		io->iop_pdirc &= ~(fip->fc_mdio);
	else
		io->iop_pdatc |= fip->fc_mdio;
	io->iop_pdatc |= fip->fc_mdck;

	/* I do this mainly to get just a little delay.
	*/
	restore_flags(flags);
	save_flags(flags);
	cli();
	io->iop_pdatc &= ~(fip->fc_mdck);
	io->iop_pdirc &= ~(fip->fc_mdio);
	io->iop_pdatc |= fip->fc_mdck;

	restore_flags(flags);
	save_flags(flags);
	cli();

	/* For read, clock in 16 bits.  For write, clock out
	 * rest of command.
	 */
	if (read_op) {
		io->iop_pdatc &= ~(fip->fc_mdck);
		udelay(0);
		for (i=0; i<16; i++) {
			io->iop_pdatc |= fip->fc_mdck;
			udelay(0);
			retval <<= 1;
			if (io->iop_pdatc & fip->fc_mdio)
				retval |= 1;
			io->iop_pdatc &= ~(fip->fc_mdck);
			udelay(0);
		}
	}
	else {
		for (i=0; i<16; i++) {
			io->iop_pdatc &= ~(fip->fc_mdck);
			if (cmd & 0x80000000)
				io->iop_pdatc |= fip->fc_mdio;
			else
				io->iop_pdatc &= ~(fip->fc_mdio);
			cmd <<= 1;
			io->iop_pdatc |= fip->fc_mdck;
			udelay(0);
		}
		io->iop_pdatc &= ~(fip->fc_mdck);
	}
	restore_flags(flags);

	/* Some diagrams show two 1 bits for "idle".  I don't know if
	 * this is really necessary or if it was just to indicate nothing
	 * is going to happen for a while.
	 * Make the data pin an output, set the data high, and clock it.
	 */
	save_flags(flags);
	cli();
	io->iop_pdatc |= fip->fc_mdio;
	io->iop_pdirc |= fip->fc_mdio;
	for (i=0; i<3; i++)
		io->iop_pdatc ^= fip->fc_mdck;
	restore_flags(flags);

	/* We exit with the same conditions as entry.
	*/
	return(retval);
}