greth.c

uboot详细解读可用启动引导LINUX2.6内核

		      (dev->gb << 8) | (dev->sp << 7) | (dev->fd << 4));

	return 0;
}

void greth_halt(struct eth_device *dev)
{
	greth_priv *greth;
	greth_regs *regs;
	int i;
#ifdef DEBUG
	printf("greth_halt\n");
#endif
	if (!dev || !dev->priv)
		return;

	greth = dev->priv;
	regs = greth->regs;

	if (!regs)
		return;

	/* disable receiver/transmitter by clearing the enable bits */
	GRETH_REGANDIN(&regs->control, ~(GRETH_RXEN | GRETH_TXEN));

	/* reset rx/tx descriptors */
	if (greth->rxbd_base) {
		for (i = 0; i < GRETH_RXBD_CNT; i++) {
			greth->rxbd_base[i].stat =
			    (i >= (GRETH_RXBD_CNT - 1)) ? GRETH_BD_WR : 0;
		}
	}

	if (greth->txbd_base) {
		for (i = 0; i < GRETH_TXBD_CNT; i++) {
			greth->txbd_base[i].stat =
			    (i >= (GRETH_TXBD_CNT - 1)) ? GRETH_BD_WR : 0;
		}
	}
}

int greth_send(struct eth_device *dev, volatile void *eth_data, int data_length)
{
	greth_priv *greth = dev->priv;
	greth_regs *regs = greth->regs;
	greth_bd *txbd;
	void *txbuf;
	unsigned int status;
#ifdef DEBUG
	printf("greth_send\n");
#endif
	/* send data, wait for data to be sent, then return */
	if (((unsigned int)eth_data & (GRETH_BUF_ALIGN - 1))
	    && !greth->gbit_mac) {
		/* data not aligned as needed by GRETH 10/100, solve this by allocating 4 byte aligned buffer
		 * and copy data to before giving it to GRETH.
		 */
		if (!greth->txbuf) {
			greth->txbuf = malloc(GRETH_RXBUF_SIZE);
#ifdef DEBUG
			printf("GRETH: allocated aligned tx-buf\n");
#endif
		}

		txbuf = greth->txbuf;

		/* copy data info buffer */
		memcpy((char *)txbuf, (char *)eth_data, data_length);

		/* keep buffer to next time */
	} else {
		txbuf = (void *)eth_data;
	}
	/* get descriptor to use, only 1 supported... hehe easy */
	txbd = greth->txbd_base;

	/* setup descriptor to wrap around to it self */
	txbd->addr = (unsigned int)txbuf;
	txbd->stat = GRETH_BD_EN | GRETH_BD_WR | data_length;

	/* Remind Core which descriptor to use when sending */
	GRETH_REGSAVE(&regs->tx_desc_p, (unsigned int)txbd);

	/* initate send by enabling transmitter */
	GRETH_REGORIN(&regs->control, GRETH_TXEN);

	/* Wait for data to be sent */
	while ((status = GRETH_REGLOAD(&txbd->stat)) & GRETH_BD_EN) {
		;
	}

	/* was the packet transmitted succesfully? */
	if (status & GRETH_TXBD_ERR_AL) {
		greth->stats.tx_limit_errors++;
	}

	if (status & GRETH_TXBD_ERR_UE) {
		greth->stats.tx_underrun_errors++;
	}

	if (status & GRETH_TXBD_ERR_LC) {
		greth->stats.tx_latecol_errors++;
	}

	if (status &
	    (GRETH_TXBD_ERR_LC | GRETH_TXBD_ERR_UE | GRETH_TXBD_ERR_AL)) {
		/* any error */
		greth->stats.tx_errors++;
		return -1;
	}

	/* bump tx packet counter */
	greth->stats.tx_packets++;

	/* return succefully */
	return 0;
}

int greth_recv(struct eth_device *dev)
{
	greth_priv *greth = dev->priv;
	greth_regs *regs = greth->regs;
	greth_bd *rxbd;
	unsigned int status, len = 0, bad;
	unsigned char *d;
	int enable = 0;
	int i;
#ifdef DEBUG
/*	printf("greth_recv\n"); */
#endif
	/* Receive One packet only, but clear as many error packets as there are
	 * available.
	 */
	{
		/* current receive descriptor */
		rxbd = greth->rxbd_curr;

		/* get status of next received packet */
		status = GRETH_REGLOAD(&rxbd->stat);

		bad = 0;

		/* stop if no more packets received */
		if (status & GRETH_BD_EN) {
			goto done;
		}
#ifdef DEBUG
		printf("greth_recv: packet 0x%lx, 0x%lx, len: %d\n",
		       (unsigned int)rxbd, status, status & GRETH_BD_LEN);
#endif

		/* Check status for errors.
		 */
		if (status & GRETH_RXBD_ERR_FT) {
			greth->stats.rx_length_errors++;
			bad = 1;
		}
		if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
			greth->stats.rx_frame_errors++;
			bad = 1;
		}
		if (status & GRETH_RXBD_ERR_CRC) {
			greth->stats.rx_crc_errors++;
			bad = 1;
		}
		if (bad) {
			greth->stats.rx_errors++;
			printf
			    ("greth_recv: Bad packet (%d, %d, %d, 0x%08x, %d)\n",
			     greth->stats.rx_length_errors,
			     greth->stats.rx_frame_errors,
			     greth->stats.rx_crc_errors, status,
			     greth->stats.rx_packets);
			/* print all rx descriptors */
			for (i = 0; i < GRETH_RXBD_CNT; i++) {
				printf("[%d]: Stat=0x%lx, Addr=0x%lx\n", i,
				       GRETH_REGLOAD(&greth->rxbd_base[i].stat),
				       GRETH_REGLOAD(&greth->rxbd_base[i].
						     addr));
			}
		} else {
			/* Process the incoming packet. */
			len = status & GRETH_BD_LEN;
			d = (char *)rxbd->addr;
#ifdef DEBUG
			printf
			    ("greth_recv: new packet, length: %d. data: %x %x %x %x %x %x %x %x\n",
			     len, d[0], d[1], d[2], d[3], d[4], d[5], d[6],
			     d[7]);
#endif
			/* flush all data cache to make sure we're not reading old packet data */
			sparc_dcache_flush_all();

			/* pass packet on to network subsystem */
			NetReceive((void *)d, len);

			/* bump stats counters */
			greth->stats.rx_packets++;

			/* bad is now 0 ==> will stop loop */
		}

		/* reenable descriptor to receive more packet with this descriptor, wrap around if needed */
		rxbd->stat =
		    GRETH_BD_EN |
		    (((unsigned int)greth->rxbd_curr >=
		      (unsigned int)greth->rxbd_max) ? GRETH_BD_WR : 0);
		enable = 1;

		/* increase index */
		greth->rxbd_curr =
		    ((unsigned int)greth->rxbd_curr >=
		     (unsigned int)greth->rxbd_max) ? greth->
		    rxbd_base : (greth->rxbd_curr + 1);

	};

	if (enable) {
		GRETH_REGORIN(&regs->control, GRETH_RXEN);
	}
      done:
	/* return positive length of packet or 0 if non recieved */
	return len;
}

void greth_set_hwaddr(greth_priv * greth, unsigned char *mac)
{
	/* save new MAC address */
	greth->dev->enetaddr[0] = greth->hwaddr[0] = mac[0];
	greth->dev->enetaddr[1] = greth->hwaddr[1] = mac[1];
	greth->dev->enetaddr[2] = greth->hwaddr[2] = mac[2];
	greth->dev->enetaddr[3] = greth->hwaddr[3] = mac[3];
	greth->dev->enetaddr[4] = greth->hwaddr[4] = mac[4];
	greth->dev->enetaddr[5] = greth->hwaddr[5] = mac[5];
	greth->regs->esa_msb = (mac[0] << 8) | mac[1];
	greth->regs->esa_lsb =
	    (mac[2] << 24) | (mac[3] << 16) | (mac[4] << 8) | mac[5];
#ifdef DEBUG
	printf("GRETH: New MAC address: %02x:%02x:%02x:%02x:%02x:%02x\n",
	       mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
#endif
}

int greth_initialize(bd_t * bis)
{
	greth_priv *greth;
	ambapp_apbdev apbdev;
	struct eth_device *dev;
	int i;
	char *addr_str, *end;
	unsigned char addr[6];
#ifdef DEBUG
	printf("Scanning for GRETH\n");
#endif
	/* Find Device & IRQ via AMBA Plug&Play information */
	if (ambapp_apb_first(VENDOR_GAISLER, GAISLER_ETHMAC, &apbdev) != 1) {
		return -1;	/* GRETH not found */
	}

	greth = (greth_priv *) malloc(sizeof(greth_priv));
	dev = (struct eth_device *)malloc(sizeof(struct eth_device));
	memset(dev, 0, sizeof(struct eth_device));
	memset(greth, 0, sizeof(greth_priv));

	greth->regs = (greth_regs *) apbdev.address;
	greth->irq = apbdev.irq;
#ifdef DEBUG
	printf("Found GRETH at 0x%lx, irq %d\n", greth->regs, greth->irq);
#endif
	dev->priv = (void *)greth;
	dev->iobase = (unsigned int)greth->regs;
	dev->init = greth_init;
	dev->halt = greth_halt;
	dev->send = greth_send;
	dev->recv = greth_recv;
	greth->dev = dev;

	/* Reset Core */
	GRETH_REGSAVE(&greth->regs->control, GRETH_RESET);

	/* Wait for core to finish reset cycle */
	while (GRETH_REGLOAD(&greth->regs->control) & GRETH_RESET) ;

	/* Get the phy address which assumed to have been set
	   correctly with the reset value in hardware */
	greth->phyaddr = (GRETH_REGLOAD(&greth->regs->mdio) >> 11) & 0x1F;

	/* Check if mac is gigabit capable */
	greth->gbit_mac = (GRETH_REGLOAD(&greth->regs->control) >> 27) & 1;

	/* Make descriptor string */
	if (greth->gbit_mac) {
		sprintf(dev->name, "GRETH 10/100/GB");
	} else {
		sprintf(dev->name, "GRETH 10/100");
	}

	/* initiate PHY, select speed/duplex depending on connected PHY */
	if (greth_init_phy(greth, bis)) {
		/* Failed to init PHY (timedout) */
		return -1;
	}

	/* Register Device to EtherNet subsystem  */
	eth_register(dev);

	/* Get MAC address */
	if ((addr_str = getenv("ethaddr")) != NULL) {
		for (i = 0; i < 6; i++) {
			addr[i] =
			    addr_str ? simple_strtoul(addr_str, &end, 16) : 0;
			if (addr_str) {
				addr_str = (*end) ? end + 1 : end;
			}
		}
	} else {
		/* HW Address not found in environment, Set default HW address */
		addr[0] = GRETH_HWADDR_0;	/* MSB */
		addr[1] = GRETH_HWADDR_1;
		addr[2] = GRETH_HWADDR_2;
		addr[3] = GRETH_HWADDR_3;
		addr[4] = GRETH_HWADDR_4;
		addr[5] = GRETH_HWADDR_5;	/* LSB */
	}

	/* set and remember MAC address */
	greth_set_hwaddr(greth, addr);

	return 1;
}