SPARC/LEON3: Added GRETH Ethernet 10/100/1000 driver.

GRETH is an Ethernet 10/100 or 10/100/1000 MAC with out without
a debug link (EDCL). The GRETH core is documented in GRIP.pdf
available at www.gaisler.com.

If the GRETH has GigaBit support (GBIT, Scatter gather, checksum
offloading etc.) can be determined by a bit in the control register.
The GBIT MAC is supported by operating in GRTEH 10/100 legacy mode.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>

4 files changed, 763 insertions, 0 deletions

diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 320dc3e..eafd267 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -35,6 +35,7 @@ COBJS-y += e1000.o
 COBJS-y += eepro100.o
 COBJS-y += enc28j60.o
 COBJS-y += fsl_mcdmafec.o
+COBJS-$(CONFIG_GRETH) += greth.o
 COBJS-y += inca-ip_sw.o
 COBJS-y += ks8695eth.o
 COBJS-y += lan91c96.o
diff --git a/drivers/net/greth.c b/drivers/net/greth.c
new file mode 100644
index 0000000..76ece59
--- /dev/null
+++ b/drivers/net/greth.c
@@ -0,0 +1,661 @@
+/* Gaisler.com GRETH 10/100/1000 Ethernet MAC driver
+ *
+ * Driver use polling mode (no Interrupt)
+ *
+ * (C) Copyright 2007
+ * Daniel Hellstrom, Gaisler Research, daniel@gaisler.com
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <command.h>
+#include <net.h>
+#include <malloc.h>
+#include <asm/processor.h>
+#include <ambapp.h>
+#include <asm/leon.h>
+
+/* #define DEBUG */
+
+#include "greth.h"
+
+/* Default to 3s timeout on autonegotiation */
+#ifndef GRETH_PHY_TIMEOUT_MS
+#define GRETH_PHY_TIMEOUT_MS 3000
+#endif
+
+/* ByPass Cache when reading regs */
+#define GRETH_REGLOAD(addr)		SPARC_NOCACHE_READ(addr)
+/* Write-through cache ==> no bypassing needed on writes */
+#define GRETH_REGSAVE(addr,data)	(*(unsigned int *)(addr) = (data))
+#define GRETH_REGORIN(addr,data) GRETH_REGSAVE(addr,GRETH_REGLOAD(addr)|data)
+#define GRETH_REGANDIN(addr,data) GRETH_REGSAVE(addr,GRETH_REGLOAD(addr)&data)
+
+#define GRETH_RXBD_CNT 4
+#define GRETH_TXBD_CNT 1
+
+#define GRETH_RXBUF_SIZE 1540
+#define GRETH_BUF_ALIGN 4
+#define GRETH_RXBUF_EFF_SIZE \
+	( (GRETH_RXBUF_SIZE&~(GRETH_BUF_ALIGN-1))+GRETH_BUF_ALIGN )
+
+typedef struct {
+	greth_regs *regs;
+	int irq;
+	struct eth_device *dev;
+
+	/* Hardware info */
+	unsigned char phyaddr;
+	int gbit_mac;
+
+	/* Current operating Mode */
+	int gb;			/* GigaBit */
+	int fd;			/* Full Duplex */
+	int sp;			/* 10/100Mbps speed (1=100,0=10) */
+	int auto_neg;		/* Auto negotiate done */
+
+	unsigned char hwaddr[6];	/* MAC Address */
+
+	/* Descriptors */
+	greth_bd *rxbd_base, *rxbd_max;
+	greth_bd *txbd_base, *txbd_max;
+
+	greth_bd *rxbd_curr;
+
+	/* rx buffers in rx descriptors */
+	void *rxbuf_base;	/* (GRETH_RXBUF_SIZE+ALIGNBYTES) * GRETH_RXBD_CNT */
+
+	/* unused for gbit_mac, temp buffer for sending packets with unligned
+	 * start.
+	 * Pointer to packet allocated with malloc.
+	 */
+	void *txbuf;
+
+	struct {
+		/* rx status */
+		unsigned int rx_packets,
+		    rx_crc_errors, rx_frame_errors, rx_length_errors, rx_errors;
+
+		/* tx stats */
+		unsigned int tx_packets,
+		    tx_latecol_errors,
+		    tx_underrun_errors, tx_limit_errors, tx_errors;
+	} stats;
+} greth_priv;
+
+/* Read MII register 'addr' from core 'regs' */
+static int read_mii(int addr, volatile greth_regs * regs)
+{
+	while (GRETH_REGLOAD(&regs->mdio) & GRETH_MII_BUSY) {
+	}
+
+	GRETH_REGSAVE(&regs->mdio, (0 << 11) | ((addr & 0x1F) << 6) | 2);
+
+	while (GRETH_REGLOAD(&regs->mdio) & GRETH_MII_BUSY) {
+	}
+
+	if (!(GRETH_REGLOAD(&regs->mdio) & GRETH_MII_NVALID)) {
+		return (GRETH_REGLOAD(&regs->mdio) >> 16) & 0xFFFF;
+	} else {
+		return -1;
+	}
+}
+
+static void write_mii(int addr, int data, volatile greth_regs * regs)
+{
+	while (GRETH_REGLOAD(&regs->mdio) & GRETH_MII_BUSY) {
+	}
+
+	GRETH_REGSAVE(&regs->mdio,
+		      ((data & 0xFFFF) << 16) | (0 << 11) | ((addr & 0x1F) << 6)
+		      | 1);
+
+	while (GRETH_REGLOAD(&regs->mdio) & GRETH_MII_BUSY) {
+	}
+
+}
+
+/* init/start hardware and allocate descriptor buffers for rx side
+ *
+ */
+int greth_init(struct eth_device *dev, bd_t * bis)
+{
+	int i;
+
+	greth_priv *greth = dev->priv;
+	greth_regs *regs = greth->regs;
+#ifdef DEBUG
+	printf("greth_init\n");
+#endif
+
+	GRETH_REGSAVE(&regs->control, 0);
+
+	if (!greth->rxbd_base) {
+
+		/* allocate descriptors */
+		greth->rxbd_base = (greth_bd *)
+		    memalign(0x1000, GRETH_RXBD_CNT * sizeof(greth_bd));
+		greth->txbd_base = (greth_bd *)
+		    memalign(0x1000, GRETH_RXBD_CNT * sizeof(greth_bd));
+
+		/* allocate buffers to all descriptors  */
+		greth->rxbuf_base =
+		    malloc(GRETH_RXBUF_EFF_SIZE * GRETH_RXBD_CNT);
+	}
+
+	/* initate rx decriptors */
+	for (i = 0; i < GRETH_RXBD_CNT; i++) {
+		greth->rxbd_base[i].addr = (unsigned int)
+		    greth->rxbuf_base + (GRETH_RXBUF_EFF_SIZE * i);
+		/* enable desciptor & set wrap bit if last descriptor */
+		if (i >= (GRETH_RXBD_CNT - 1)) {
+			greth->rxbd_base[i].stat = GRETH_BD_EN | GRETH_BD_WR;
+		} else {
+			greth->rxbd_base[i].stat = GRETH_BD_EN;
+		}
+	}
+
+	/* initiate indexes */
+	greth->rxbd_curr = greth->rxbd_base;
+	greth->rxbd_max = greth->rxbd_base + (GRETH_RXBD_CNT - 1);
+	greth->txbd_max = greth->txbd_base + (GRETH_TXBD_CNT - 1);
+	/*
+	 * greth->txbd_base->addr = 0;
+	 * greth->txbd_base->stat = GRETH_BD_WR;
+	 */
+
+	/* initate tx decriptors */
+	for (i = 0; i < GRETH_TXBD_CNT; i++) {
+		greth->txbd_base[i].addr = 0;
+		/* enable desciptor & set wrap bit if last descriptor */
+		if (i >= (GRETH_RXBD_CNT - 1)) {
+			greth->txbd_base[i].stat = GRETH_BD_WR;
+		} else {
+			greth->txbd_base[i].stat = 0;
+		}
+	}
+
+	/**** SET HARDWARE REGS ****/
+
+	/* Set pointer to tx/rx descriptor areas */
+	GRETH_REGSAVE(&regs->rx_desc_p, (unsigned int)&greth->rxbd_base[0]);
+	GRETH_REGSAVE(&regs->tx_desc_p, (unsigned int)&greth->txbd_base[0]);
+
+	/* Enable Transmitter, GRETH will now scan descriptors for packets
+	 * to transmitt */
+#ifdef DEBUG
+	printf("greth_init: enabling receiver\n");
+#endif
+	GRETH_REGORIN(&regs->control, GRETH_RXEN);
+
+	return 0;
+}
+
+/* Initiate PHY to a relevant speed
+ * return:
+ *  - 0 = success
+ *  - 1 = timeout/fail
+ */
+int greth_init_phy(greth_priv * dev, bd_t * bis)
+{
+	greth_regs *regs = dev->regs;
+	int tmp, tmp1, tmp2, i;
+	unsigned int start, timeout;
+
+	/* X msecs to ticks */
+	timeout = usec2ticks(GRETH_PHY_TIMEOUT_MS * 1000);
+
+	/* Get system timer0 current value
+	 * Total timeout is 5s
+	 */
+	start = get_timer(0);
+
+	/* get phy control register default values */
+
+	while ((tmp = read_mii(0, regs)) & 0x8000) {
+		if (get_timer(start) > timeout)
+			return 1;	/* Fail */
+	}
+
+	/* reset PHY and wait for completion */
+	write_mii(0, 0x8000 | tmp, regs);
+
+	while (((tmp = read_mii(0, regs))) & 0x8000) {
+		if (get_timer(start) > timeout)
+			return 1;	/* Fail */
+	}
+
+	/* Check if PHY is autoneg capable and then determine operating
+	 * mode, otherwise force it to 10 Mbit halfduplex
+	 */
+	dev->gb = 0;
+	dev->fd = 0;
+	dev->sp = 0;
+	dev->auto_neg = 0;
+	if (!((tmp >> 12) & 1)) {
+		write_mii(0, 0, regs);
+	} else {
+		/* wait for auto negotiation to complete and then check operating mode */
+		dev->auto_neg = 1;
+		i = 0;
+		while (!(((tmp = read_mii(1, regs)) >> 5) & 1)) {
+			if (get_timer(start) > timeout) {
+				printf("Auto negotiation timed out. "
+				       "Selecting default config\n");
+				tmp = read_mii(0, regs);
+				dev->gb = ((tmp >> 6) & 1)
+				    && !((tmp >> 13) & 1);
+				dev->sp = !((tmp >> 6) & 1)
+				    && ((tmp >> 13) & 1);
+				dev->fd = (tmp >> 8) & 1;
+				goto auto_neg_done;
+			}
+		}
+		if ((tmp >> 8) & 1) {
+			tmp1 = read_mii(9, regs);
+			tmp2 = read_mii(10, regs);
+			if ((tmp1 & GRETH_MII_EXTADV_1000FD) &&
+			    (tmp2 & GRETH_MII_EXTPRT_1000FD)) {
+				dev->gb = 1;
+				dev->fd = 1;
+			}
+			if ((tmp1 & GRETH_MII_EXTADV_1000HD) &&
+			    (tmp2 & GRETH_MII_EXTPRT_1000HD)) {
+				dev->gb = 1;
+				dev->fd = 0;
+			}
+		}
+		if ((dev->gb == 0) || ((dev->gb == 1) && (dev->gbit_mac == 0))) {
+			tmp1 = read_mii(4, regs);
+			tmp2 = read_mii(5, regs);
+			if ((tmp1 & GRETH_MII_100TXFD) &&
+			    (tmp2 & GRETH_MII_100TXFD)) {
+				dev->sp = 1;
+				dev->fd = 1;
+			}
+			if ((tmp1 & GRETH_MII_100TXHD) &&
+			    (tmp2 & GRETH_MII_100TXHD)) {
+				dev->sp = 1;
+				dev->fd = 0;
+			}
+			if ((tmp1 & GRETH_MII_10FD) && (tmp2 & GRETH_MII_10FD)) {
+				dev->fd = 1;
+			}
+			if ((dev->gb == 1) && (dev->gbit_mac == 0)) {
+				dev->gb = 0;
+				dev->fd = 0;
+				write_mii(0, dev->sp << 13, regs);
+			}
+		}
+
+	}
+      auto_neg_done:
+#ifdef DEBUG
+	printf("%s GRETH Ethermac at [0x%x] irq %d. Running \
+		%d Mbps %s duplex\n", dev->gbit_mac ? "10/100/1000" : "10/100", (unsigned int)(regs), (unsigned int)(dev->irq), dev->gb ? 1000 : (dev->sp ? 100 : 10), dev->fd ? "full" : "half");
+#endif
+	/* Read out PHY info if extended registers are available */
+	if (tmp & 1) {
+		tmp1 = read_mii(2, regs);
+		tmp2 = read_mii(3, regs);
+		tmp1 = (tmp1 << 6) | ((tmp2 >> 10) & 0x3F);
+		tmp = tmp2 & 0xF;
+
+		tmp2 = (tmp2 >> 4) & 0x3F;
+#ifdef DEBUG
+		printf("PHY: Vendor %x   Device %x    Revision %d\n", tmp1,
+		       tmp2, tmp);
+#endif
+	} else {
+		printf("PHY info not available\n");
+	}
+
+	/* set speed and duplex bits in control register */
+	GRETH_REGORIN(&regs->control,
+		      (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;
+}
diff --git a/drivers/net/greth.h b/drivers/net/greth.h
new file mode 100644
index 0000000..7d5fbd3
--- /dev/null
+++ b/drivers/net/greth.h
@@ -0,0 +1,97 @@
+/* Gaisler.com GRETH 10/100/1000 Ethernet MAC driver
+ *
+ * (C) Copyright 2007
+ * Daniel Hellstrom, Gaisler Research, daniel@gaisler.com
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#define GRETH_FD 0x10
+#define GRETH_RESET 0x40
+#define GRETH_MII_BUSY 0x8
+#define GRETH_MII_NVALID 0x10
+
+/* MII registers */
+#define GRETH_MII_EXTADV_1000FD 0x00000200
+#define GRETH_MII_EXTADV_1000HD 0x00000100
+#define GRETH_MII_EXTPRT_1000FD 0x00000800
+#define GRETH_MII_EXTPRT_1000HD 0x00000400
+
+#define GRETH_MII_100T4 0x00000200
+#define GRETH_MII_100TXFD 0x00000100
+#define GRETH_MII_100TXHD 0x00000080
+#define GRETH_MII_10FD 0x00000040
+#define GRETH_MII_10HD 0x00000020
+
+#define GRETH_BD_EN 0x800
+#define GRETH_BD_WR 0x1000
+#define GRETH_BD_IE 0x2000
+#define GRETH_BD_LEN 0x7FF
+
+#define GRETH_TXEN 0x1
+#define GRETH_INT_TX 0x8
+#define GRETH_TXI 0x4
+#define GRETH_TXBD_STATUS 0x0001C000
+#define GRETH_TXBD_MORE 0x20000
+#define GRETH_TXBD_IPCS 0x40000
+#define GRETH_TXBD_TCPCS 0x80000
+#define GRETH_TXBD_UDPCS 0x100000
+#define GRETH_TXBD_ERR_LC 0x10000
+#define GRETH_TXBD_ERR_UE 0x4000
+#define GRETH_TXBD_ERR_AL 0x8000
+#define GRETH_TXBD_NUM 128
+#define GRETH_TXBD_NUM_MASK (GRETH_TXBD_NUM-1)
+#define GRETH_TX_BUF_SIZE 2048
+
+#define GRETH_INT_RX         0x4
+#define GRETH_RXEN           0x2
+#define GRETH_RXI            0x8
+#define GRETH_RXBD_STATUS    0xFFFFC000
+#define GRETH_RXBD_ERR_AE    0x4000
+#define GRETH_RXBD_ERR_FT    0x8000
+#define GRETH_RXBD_ERR_CRC   0x10000
+#define GRETH_RXBD_ERR_OE    0x20000
+#define GRETH_RXBD_ERR_LE    0x40000
+#define GRETH_RXBD_IP_DEC    0x80000
+#define GRETH_RXBD_IP_CSERR  0x100000
+#define GRETH_RXBD_UDP_DEC   0x200000
+#define GRETH_RXBD_UDP_CSERR 0x400000
+#define GRETH_RXBD_TCP_DEC   0x800000
+#define GRETH_RXBD_TCP_CSERR 0x1000000
+
+#define GRETH_RXBD_NUM 128
+#define GRETH_RXBD_NUM_MASK (GRETH_RXBD_NUM-1)
+#define GRETH_RX_BUF_SIZE 2048
+
+/* Ethernet configuration registers */
+typedef struct _greth_regs {
+	volatile unsigned int control;
+	volatile unsigned int status;
+	volatile unsigned int esa_msb;
+	volatile unsigned int esa_lsb;
+	volatile unsigned int mdio;
+	volatile unsigned int tx_desc_p;
+	volatile unsigned int rx_desc_p;
+} greth_regs;
+
+/* Ethernet buffer descriptor */
+typedef struct _greth_bd {
+	volatile unsigned int stat;
+	unsigned int addr;	/* Buffer address not changed by HW */
+} greth_bd;
diff --git a/net/eth.c b/net/eth.c
index 16a6dcb..3b86f87 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -60,6 +60,7 @@ extern int npe_initialize(bd_t *);
 extern int uec_initialize(int);
 extern int bfin_EMAC_initialize(bd_t *);
 extern int atstk1000_eth_initialize(bd_t *);
+extern int greth_initialize(bd_t *);
 extern int atngw100_eth_initialize(bd_t *);
 extern int mcffec_initialize(bd_t*);
 extern int mcdmafec_initialize(bd_t*);
@@ -275,6 +276,9 @@ int eth_initialize(bd_t *bis)
 #if defined(CONFIG_ATSTK1000)
 	atstk1000_eth_initialize(bis);
 #endif
+#if defined(CONFIG_GRETH)
+	greth_initialize(bis);
+#endif
 #if defined(CONFIG_ATNGW100)
 	atngw100_eth_initialize(bis);
 #endif