drivers/net/ep93xx_eth.c - github/trini/u-boot - Gitiles

 /*
  * Cirrus Logic EP93xx ethernet MAC / MII driver.
  *
  * Copyright (C) 2010, 2009
  * Matthias Kaehlcke <matthias@kaehlcke.net>
  *
  * Copyright (C) 2004, 2005
  * Cory T. Tusar, Videon Central, Inc., <ctusar@videon-central.com>
  *
  * Based on the original eth.[ch] Cirrus Logic EP93xx Rev D. Ethernet Driver,
  * which is
  *
  * (C) Copyright 2002 2003
  * Adam Bezanson, Network Audio Technologies, Inc.
  * <bezanson@netaudiotech.com>
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */

 #include <command.h>
 #include <common.h>
 #include <asm/arch/ep93xx.h>
 #include <asm/io.h>
 #include <malloc.h>
 #include <miiphy.h>
 #include <linux/types.h>
 #include "ep93xx_eth.h"

 #define GET_PRIV(eth_dev)	((struct ep93xx_priv *)(eth_dev)->priv)
 #define GET_REGS(eth_dev)	(GET_PRIV(eth_dev)->regs)

 /* ep93xx_miiphy ops forward declarations */
 static int ep93xx_miiphy_read(const char * const dev, unsigned char const addr,
 			unsigned char const reg, unsigned short * const value);
 static int ep93xx_miiphy_write(const char * const dev, unsigned char const addr,
 			unsigned char const reg, unsigned short const value);

 #if defined(EP93XX_MAC_DEBUG)
 /**
  * Dump ep93xx_mac values to the terminal.
  */
 static void dump_dev(struct eth_device *dev)
 {
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	int i;

 	printf("\ndump_dev()\n");
 	printf("  rx_dq.base	     %p\n", priv->rx_dq.base);
 	printf("  rx_dq.current	     %p\n", priv->rx_dq.current);
 	printf("  rx_dq.end	     %p\n", priv->rx_dq.end);
 	printf("  rx_sq.base	     %p\n", priv->rx_sq.base);
 	printf("  rx_sq.current	     %p\n", priv->rx_sq.current);
 	printf("  rx_sq.end	     %p\n", priv->rx_sq.end);

 	for (i = 0; i < NUMRXDESC; i++)
 		printf("  rx_buffer[%2.d]      %p\n", i, NetRxPackets[i]);

 	printf("  tx_dq.base	     %p\n", priv->tx_dq.base);
 	printf("  tx_dq.current	     %p\n", priv->tx_dq.current);
 	printf("  tx_dq.end	     %p\n", priv->tx_dq.end);
 	printf("  tx_sq.base	     %p\n", priv->tx_sq.base);
 	printf("  tx_sq.current	     %p\n", priv->tx_sq.current);
 	printf("  tx_sq.end	     %p\n", priv->tx_sq.end);
 }

 /**
  * Dump all RX status queue entries to the terminal.
  */
 static void dump_rx_status_queue(struct eth_device *dev)
 {
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	int i;

 	printf("\ndump_rx_status_queue()\n");
 	printf("  descriptor address	 word1		 word2\n");
 	for (i = 0; i < NUMRXDESC; i++) {
 		printf("  [ %p ]	     %08X	 %08X\n",
 			priv->rx_sq.base + i,
 			(priv->rx_sq.base + i)->word1,
 			(priv->rx_sq.base + i)->word2);
 	}
 }

 /**
  * Dump all RX descriptor queue entries to the terminal.
  */
 static void dump_rx_descriptor_queue(struct eth_device *dev)
 {
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	int i;

 	printf("\ndump_rx_descriptor_queue()\n");
 	printf("  descriptor address	 word1		 word2\n");
 	for (i = 0; i < NUMRXDESC; i++) {
 		printf("  [ %p ]	     %08X	 %08X\n",
 			priv->rx_dq.base + i,
 			(priv->rx_dq.base + i)->word1,
 			(priv->rx_dq.base + i)->word2);
 	}
 }

 /**
  * Dump all TX descriptor queue entries to the terminal.
  */
 static void dump_tx_descriptor_queue(struct eth_device *dev)
 {
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	int i;

 	printf("\ndump_tx_descriptor_queue()\n");
 	printf("  descriptor address	 word1		 word2\n");
 	for (i = 0; i < NUMTXDESC; i++) {
 		printf("  [ %p ]	     %08X	 %08X\n",
 			priv->tx_dq.base + i,
 			(priv->tx_dq.base + i)->word1,
 			(priv->tx_dq.base + i)->word2);
 	}
 }

 /**
  * Dump all TX status queue entries to the terminal.
  */
 static void dump_tx_status_queue(struct eth_device *dev)
 {
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	int i;

 	printf("\ndump_tx_status_queue()\n");
 	printf("  descriptor address	 word1\n");
 	for (i = 0; i < NUMTXDESC; i++) {
 		printf("  [ %p ]	     %08X\n",
 			priv->rx_sq.base + i,
 			(priv->rx_sq.base + i)->word1);
 	}
 }
 #else
 #define dump_dev(x)
 #define dump_rx_descriptor_queue(x)
 #define dump_rx_status_queue(x)
 #define dump_tx_descriptor_queue(x)
 #define dump_tx_status_queue(x)
 #endif	/* defined(EP93XX_MAC_DEBUG) */

 /**
  * Reset the EP93xx MAC by twiddling the soft reset bit and spinning until
  * it's cleared.
  */
 static void ep93xx_mac_reset(struct eth_device *dev)
 {
 	struct mac_regs *mac = GET_REGS(dev);
 	uint32_t value;

 	debug("+ep93xx_mac_reset");

 	value = readl(&mac->selfctl);
 	value |= SELFCTL_RESET;
 	writel(value, &mac->selfctl);

 	while (readl(&mac->selfctl) & SELFCTL_RESET)
 		; /* noop */

 	debug("-ep93xx_mac_reset");
 }

 /* Eth device open */
 static int ep93xx_eth_open(struct eth_device *dev, bd_t *bd)
 {
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	struct mac_regs *mac = GET_REGS(dev);
 	uchar *mac_addr = dev->enetaddr;
 	int i;

 	debug("+ep93xx_eth_open");

 	/* Reset the MAC */
 	ep93xx_mac_reset(dev);

 	/* Reset the descriptor queues' current and end address values */
 	priv->tx_dq.current = priv->tx_dq.base;
 	priv->tx_dq.end = (priv->tx_dq.base + NUMTXDESC);

 	priv->tx_sq.current = priv->tx_sq.base;
 	priv->tx_sq.end = (priv->tx_sq.base + NUMTXDESC);

 	priv->rx_dq.current = priv->rx_dq.base;
 	priv->rx_dq.end = (priv->rx_dq.base + NUMRXDESC);

 	priv->rx_sq.current = priv->rx_sq.base;
 	priv->rx_sq.end = (priv->rx_sq.base + NUMRXDESC);

 	/*
 	 * Set the transmit descriptor and status queues' base address,
 	 * current address, and length registers.  Set the maximum frame
 	 * length and threshold. Enable the transmit descriptor processor.
 	 */
 	writel((uint32_t)priv->tx_dq.base, &mac->txdq.badd);
 	writel((uint32_t)priv->tx_dq.base, &mac->txdq.curadd);
 	writel(sizeof(struct tx_descriptor) * NUMTXDESC, &mac->txdq.blen);

 	writel((uint32_t)priv->tx_sq.base, &mac->txstsq.badd);
 	writel((uint32_t)priv->tx_sq.base, &mac->txstsq.curadd);
 	writel(sizeof(struct tx_status) * NUMTXDESC, &mac->txstsq.blen);

 	writel(0x00040000, &mac->txdthrshld);
 	writel(0x00040000, &mac->txststhrshld);

 	writel((TXSTARTMAX << 0) | (PKTSIZE_ALIGN << 16), &mac->maxfrmlen);
 	writel(BMCTL_TXEN, &mac->bmctl);

 	/*
 	 * Set the receive descriptor and status queues' base address,
 	 * current address, and length registers.  Enable the receive
 	 * descriptor processor.
 	 */
 	writel((uint32_t)priv->rx_dq.base, &mac->rxdq.badd);
 	writel((uint32_t)priv->rx_dq.base, &mac->rxdq.curadd);
 	writel(sizeof(struct rx_descriptor) * NUMRXDESC, &mac->rxdq.blen);

 	writel((uint32_t)priv->rx_sq.base, &mac->rxstsq.badd);
 	writel((uint32_t)priv->rx_sq.base, &mac->rxstsq.curadd);
 	writel(sizeof(struct rx_status) * NUMRXDESC, &mac->rxstsq.blen);

 	writel(0x00040000, &mac->rxdthrshld);

 	writel(BMCTL_RXEN, &mac->bmctl);

 	writel(0x00040000, &mac->rxststhrshld);

 	/* Wait until the receive descriptor processor is active */
 	while (!(readl(&mac->bmsts) & BMSTS_RXACT))
 		; /* noop */

 	/*
 	 * Initialize the RX descriptor queue. Clear the TX descriptor queue.
 	 * Clear the RX and TX status queues. Enqueue the RX descriptor and
 	 * status entries to the MAC.
 	 */
 	for (i = 0; i < NUMRXDESC; i++) {
 		/* set buffer address */
 		(priv->rx_dq.base + i)->word1 = (uint32_t)NetRxPackets[i];

 		/* set buffer length, clear buffer index and NSOF */
 		(priv->rx_dq.base + i)->word2 = PKTSIZE_ALIGN;
 	}

 	memset(priv->tx_dq.base, 0,
 		(sizeof(struct tx_descriptor) * NUMTXDESC));
 	memset(priv->rx_sq.base, 0,
 		(sizeof(struct rx_status) * NUMRXDESC));
 	memset(priv->tx_sq.base, 0,
 		(sizeof(struct tx_status) * NUMTXDESC));

 	writel(NUMRXDESC, &mac->rxdqenq);
 	writel(NUMRXDESC, &mac->rxstsqenq);

 	/* Set the primary MAC address */
 	writel(AFP_IAPRIMARY, &mac->afp);
 	writel(mac_addr[0] | (mac_addr[1] << 8) |
 		(mac_addr[2] << 16) | (mac_addr[3] << 24),
 		&mac->indad);
 	writel(mac_addr[4] | (mac_addr[5] << 8), &mac->indad_upper);

 	/* Turn on RX and TX */
 	writel(RXCTL_IA0 | RXCTL_BA | RXCTL_SRXON |
 		RXCTL_RCRCA | RXCTL_MA, &mac->rxctl);
 	writel(TXCTL_STXON, &mac->txctl);

 	/* Dump data structures if we're debugging */
 	dump_dev(dev);
 	dump_rx_descriptor_queue(dev);
 	dump_rx_status_queue(dev);
 	dump_tx_descriptor_queue(dev);
 	dump_tx_status_queue(dev);

 	debug("-ep93xx_eth_open");

 	return 1;
 }

 /**
  * Halt EP93xx MAC transmit and receive by clearing the TxCTL and RxCTL
  * registers.
  */
 static void ep93xx_eth_close(struct eth_device *dev)
 {
 	struct mac_regs *mac = GET_REGS(dev);

 	debug("+ep93xx_eth_close");

 	writel(0x00000000, &mac->rxctl);
 	writel(0x00000000, &mac->txctl);

 	debug("-ep93xx_eth_close");
 }

 /**
  * Copy a frame of data from the MAC into the protocol layer for further
  * processing.
  */
 static int ep93xx_eth_rcv_packet(struct eth_device *dev)
 {
 	struct mac_regs *mac = GET_REGS(dev);
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	int len = -1;

 	debug("+ep93xx_eth_rcv_packet");

 	if (RX_STATUS_RFP(priv->rx_sq.current)) {
 		if (RX_STATUS_RWE(priv->rx_sq.current)) {
 			/*
 			 * We have a good frame. Extract the frame's length
 			 * from the current rx_status_queue entry, and copy
 			 * the frame's data into NetRxPackets[] of the
 			 * protocol stack. We track the total number of
 			 * bytes in the frame (nbytes_frame) which will be
 			 * used when we pass the data off to the protocol
 			 * layer via NetReceive().
 			 */
 			len = RX_STATUS_FRAME_LEN(priv->rx_sq.current);

 			NetReceive((uchar *)priv->rx_dq.current->word1,	len);

 			debug("reporting %d bytes...\n", len);
 		} else {
 			/* Do we have an erroneous packet? */
 			error("packet rx error, status %08X %08X",
 				priv->rx_sq.current->word1,
 				priv->rx_sq.current->word2);
 			dump_rx_descriptor_queue(dev);
 			dump_rx_status_queue(dev);
 		}

 		/*
 		 * Clear the associated status queue entry, and
 		 * increment our current pointers to the next RX
 		 * descriptor and status queue entries (making sure
 		 * we wrap properly).
 		 */
 		memset((void *)priv->rx_sq.current, 0,
 			sizeof(struct rx_status));

 		priv->rx_sq.current++;
 		if (priv->rx_sq.current >= priv->rx_sq.end)
 			priv->rx_sq.current = priv->rx_sq.base;

 		priv->rx_dq.current++;
 		if (priv->rx_dq.current >= priv->rx_dq.end)
 			priv->rx_dq.current = priv->rx_dq.base;

 		/*
 		 * Finally, return the RX descriptor and status entries
 		 * back to the MAC engine, and loop again, checking for
 		 * more descriptors to process.
 		 */
 		writel(1, &mac->rxdqenq);
 		writel(1, &mac->rxstsqenq);
 	} else {
 		len = 0;
 	}

 	debug("-ep93xx_eth_rcv_packet %d", len);
 	return len;
 }

 /**
  * Send a block of data via ethernet.
  */
 static int ep93xx_eth_send_packet(struct eth_device *dev,
 				void * const packet, int const length)
 {
 	struct mac_regs *mac = GET_REGS(dev);
 	struct ep93xx_priv *priv = GET_PRIV(dev);
 	int ret = -1;

 	debug("+ep93xx_eth_send_packet");

 	/* Parameter check */
 	BUG_ON(packet == NULL);

 	/*
 	 * Initialize the TX descriptor queue with the new packet's info.
 	 * Clear the associated status queue entry. Enqueue the packet
 	 * to the MAC for transmission.
 	 */

 	/* set buffer address */
 	priv->tx_dq.current->word1 = (uint32_t)packet;

 	/* set buffer length and EOF bit */
 	priv->tx_dq.current->word2 = length | TX_DESC_EOF;

 	/* clear tx status */
 	priv->tx_sq.current->word1 = 0;

 	/* enqueue the TX descriptor */
 	writel(1, &mac->txdqenq);

 	/* wait for the frame to become processed */
 	while (!TX_STATUS_TXFP(priv->tx_sq.current))
 		; /* noop */

 	if (!TX_STATUS_TXWE(priv->tx_sq.current)) {
 		error("packet tx error, status %08X",
 			priv->tx_sq.current->word1);
 		dump_tx_descriptor_queue(dev);
 		dump_tx_status_queue(dev);

 		/* TODO: Add better error handling? */
 		goto eth_send_out;
 	}

 	ret = 0;
 	/* Fall through */

 eth_send_out:
 	debug("-ep93xx_eth_send_packet %d", ret);
 	return ret;
 }

 #if defined(CONFIG_MII)
 int ep93xx_miiphy_initialize(bd_t * const bd)
 {
 	miiphy_register("ep93xx_eth0", ep93xx_miiphy_read, ep93xx_miiphy_write);
 	return 0;
 }
 #endif

 /**
  * Initialize the EP93xx MAC.  The MAC hardware is reset.  Buffers are
  * allocated, if necessary, for the TX and RX descriptor and status queues,
  * as well as for received packets.  The EP93XX MAC hardware is initialized.
  * Transmit and receive operations are enabled.
  */
 int ep93xx_eth_initialize(u8 dev_num, int base_addr)
 {
 	int ret = -1;
 	struct eth_device *dev;
 	struct ep93xx_priv *priv;

 	debug("+ep93xx_eth_initialize");

 	priv = malloc(sizeof(*priv));
 	if (!priv) {
 		error("malloc() failed");
 		goto eth_init_failed_0;
 	}
 	memset(priv, 0, sizeof(*priv));

 	priv->regs = (struct mac_regs *)base_addr;

 	priv->tx_dq.base = calloc(NUMTXDESC,
 				sizeof(struct tx_descriptor));
 	if (priv->tx_dq.base == NULL) {
 		error("calloc() failed");
 		goto eth_init_failed_1;
 	}

 	priv->tx_sq.base = calloc(NUMTXDESC,
 				sizeof(struct tx_status));
 	if (priv->tx_sq.base == NULL) {
 		error("calloc() failed");
 		goto eth_init_failed_2;
 	}

 	priv->rx_dq.base = calloc(NUMRXDESC,
 				sizeof(struct rx_descriptor));
 	if (priv->rx_dq.base == NULL) {
 		error("calloc() failed");
 		goto eth_init_failed_3;
 	}

 	priv->rx_sq.base = calloc(NUMRXDESC,
 				sizeof(struct rx_status));
 	if (priv->rx_sq.base == NULL) {
 		error("calloc() failed");
 		goto eth_init_failed_4;
 	}

 	dev = malloc(sizeof *dev);
 	if (dev == NULL) {
 		error("malloc() failed");
 		goto eth_init_failed_5;
 	}
 	memset(dev, 0, sizeof *dev);

 	dev->iobase = base_addr;
 	dev->priv = priv;
 	dev->init = ep93xx_eth_open;
 	dev->halt = ep93xx_eth_close;
 	dev->send = ep93xx_eth_send_packet;
 	dev->recv = ep93xx_eth_rcv_packet;

 	sprintf(dev->name, "ep93xx_eth-%hu", dev_num);

 	eth_register(dev);

 	/* Done! */
 	ret = 1;
 	goto eth_init_done;

 eth_init_failed_5:
 	free(priv->rx_sq.base);
 	/* Fall through */

 eth_init_failed_4:
 	free(priv->rx_dq.base);
 	/* Fall through */

 eth_init_failed_3:
 	free(priv->tx_sq.base);
 	/* Fall through */

 eth_init_failed_2:
 	free(priv->tx_dq.base);
 	/* Fall through */

 eth_init_failed_1:
 	free(priv);
 	/* Fall through */

 eth_init_failed_0:
 	/* Fall through */

 eth_init_done:
 	debug("-ep93xx_eth_initialize %d", ret);
 	return ret;
 }

 #if defined(CONFIG_MII)

 /**
  * Maximum MII address we support
  */
 #define MII_ADDRESS_MAX			31

 /**
  * Maximum MII register address we support
  */
 #define MII_REGISTER_MAX		31

 /**
  * Read a 16-bit value from an MII register.
  */
 static int ep93xx_miiphy_read(const char * const dev, unsigned char const addr,
 			unsigned char const reg, unsigned short * const value)
 {
 	struct mac_regs *mac = (struct mac_regs *)MAC_BASE;
 	int ret = -1;
 	uint32_t self_ctl;

 	debug("+ep93xx_miiphy_read");

 	/* Parameter checks */
 	BUG_ON(dev == NULL);
 	BUG_ON(addr > MII_ADDRESS_MAX);
 	BUG_ON(reg > MII_REGISTER_MAX);
 	BUG_ON(value == NULL);

 	/*
 	 * Save the current SelfCTL register value.  Set MAC to suppress
 	 * preamble bits.  Wait for any previous MII command to complete
 	 * before issuing the new command.
 	 */
 	self_ctl = readl(&mac->selfctl);
 #if defined(CONFIG_MII_SUPPRESS_PREAMBLE)
 	writel(self_ctl & ~(1 << 8), &mac->selfctl);
 #endif	/* defined(CONFIG_MII_SUPPRESS_PREAMBLE) */

 	while (readl(&mac->miists) & MIISTS_BUSY)
 		; /* noop */

 	/*
 	 * Issue the MII 'read' command.  Wait for the command to complete.
 	 * Read the MII data value.
 	 */
 	writel(MIICMD_OPCODE_READ | ((uint32_t)addr << 5) | (uint32_t)reg,
 		&mac->miicmd);
 	while (readl(&mac->miists) & MIISTS_BUSY)
 		; /* noop */

 	*value = (unsigned short)readl(&mac->miidata);

 	/* Restore the saved SelfCTL value and return. */
 	writel(self_ctl, &mac->selfctl);

 	ret = 0;
 	/* Fall through */

 	debug("-ep93xx_miiphy_read");
 	return ret;
 }

 /**
  * Write a 16-bit value to an MII register.
  */
 static int ep93xx_miiphy_write(const char * const dev, unsigned char const addr,
 			unsigned char const reg, unsigned short const value)
 {
 	struct mac_regs *mac = (struct mac_regs *)MAC_BASE;
 	int ret = -1;
 	uint32_t self_ctl;

 	debug("+ep93xx_miiphy_write");

 	/* Parameter checks */
 	BUG_ON(dev == NULL);
 	BUG_ON(addr > MII_ADDRESS_MAX);
 	BUG_ON(reg > MII_REGISTER_MAX);

 	/*
 	 * Save the current SelfCTL register value.  Set MAC to suppress
 	 * preamble bits.  Wait for any previous MII command to complete
 	 * before issuing the new command.
 	 */
 	self_ctl = readl(&mac->selfctl);
 #if defined(CONFIG_MII_SUPPRESS_PREAMBLE)
 	writel(self_ctl & ~(1 << 8), &mac->selfctl);
 #endif	/* defined(CONFIG_MII_SUPPRESS_PREAMBLE) */

 	while (readl(&mac->miists) & MIISTS_BUSY)
 		; /* noop */

 	/* Issue the MII 'write' command.  Wait for the command to complete. */
 	writel((uint32_t)value, &mac->miidata);
 	writel(MIICMD_OPCODE_WRITE | ((uint32_t)addr << 5) | (uint32_t)reg,
 		&mac->miicmd);
 	while (readl(&mac->miists) & MIISTS_BUSY)
 		; /* noop */

 	/* Restore the saved SelfCTL value and return. */
 	writel(self_ctl, &mac->selfctl);

 	ret = 0;
 	/* Fall through */

 	debug("-ep93xx_miiphy_write");
 	return ret;
 }
 #endif	/* defined(CONFIG_MII) */
	/*
	* Cirrus Logic EP93xx ethernet MAC / MII driver.
	*
	* Copyright (C) 2010, 2009
	* Matthias Kaehlcke <matthias@kaehlcke.net>
	*
	* Copyright (C) 2004, 2005
	* Cory T. Tusar, Videon Central, Inc., <ctusar@videon-central.com>
	*
	* Based on the original eth.[ch] Cirrus Logic EP93xx Rev D. Ethernet Driver,
	* which is
	*
	* (C) Copyright 2002 2003
	* Adam Bezanson, Network Audio Technologies, Inc.
	* <bezanson@netaudiotech.com>
	*
	* SPDX-License-Identifier: GPL-2.0+
	*/

	#include <command.h>
	#include <common.h>
	#include <asm/arch/ep93xx.h>
	#include <asm/io.h>
	#include <malloc.h>
	#include <miiphy.h>
	#include <linux/types.h>
	#include "ep93xx_eth.h"

	#define GET_PRIV(eth_dev) ((struct ep93xx_priv *)(eth_dev)->priv)
	#define GET_REGS(eth_dev) (GET_PRIV(eth_dev)->regs)

	/* ep93xx_miiphy ops forward declarations */
	static int ep93xx_miiphy_read(const char * const dev, unsigned char const addr,
	unsigned char const reg, unsigned short * const value);
	static int ep93xx_miiphy_write(const char * const dev, unsigned char const addr,
	unsigned char const reg, unsigned short const value);

	#if defined(EP93XX_MAC_DEBUG)
	/**
	* Dump ep93xx_mac values to the terminal.
	*/
	static void dump_dev(struct eth_device *dev)
	{
	struct ep93xx_priv *priv = GET_PRIV(dev);
	int i;

	printf("\ndump_dev()\n");
	printf(" rx_dq.base %p\n", priv->rx_dq.base);
	printf(" rx_dq.current %p\n", priv->rx_dq.current);
	printf(" rx_dq.end %p\n", priv->rx_dq.end);
	printf(" rx_sq.base %p\n", priv->rx_sq.base);
	printf(" rx_sq.current %p\n", priv->rx_sq.current);
	printf(" rx_sq.end %p\n", priv->rx_sq.end);

	for (i = 0; i < NUMRXDESC; i++)
	printf(" rx_buffer[%2.d] %p\n", i, NetRxPackets[i]);

	printf(" tx_dq.base %p\n", priv->tx_dq.base);
	printf(" tx_dq.current %p\n", priv->tx_dq.current);
	printf(" tx_dq.end %p\n", priv->tx_dq.end);
	printf(" tx_sq.base %p\n", priv->tx_sq.base);
	printf(" tx_sq.current %p\n", priv->tx_sq.current);
	printf(" tx_sq.end %p\n", priv->tx_sq.end);
	}

	/**
	* Dump all RX status queue entries to the terminal.
	*/
	static void dump_rx_status_queue(struct eth_device *dev)
	{
	struct ep93xx_priv *priv = GET_PRIV(dev);
	int i;

	printf("\ndump_rx_status_queue()\n");
	printf(" descriptor address word1 word2\n");
	for (i = 0; i < NUMRXDESC; i++) {
	printf(" [ %p ] %08X %08X\n",
	priv->rx_sq.base + i,
	(priv->rx_sq.base + i)->word1,
	(priv->rx_sq.base + i)->word2);
	}
	}

	/**
	* Dump all RX descriptor queue entries to the terminal.
	*/
	static void dump_rx_descriptor_queue(struct eth_device *dev)
	{
	struct ep93xx_priv *priv = GET_PRIV(dev);
	int i;

	printf("\ndump_rx_descriptor_queue()\n");
	printf(" descriptor address word1 word2\n");
	for (i = 0; i < NUMRXDESC; i++) {
	printf(" [ %p ] %08X %08X\n",
	priv->rx_dq.base + i,
	(priv->rx_dq.base + i)->word1,
	(priv->rx_dq.base + i)->word2);
	}
	}

	/**
	* Dump all TX descriptor queue entries to the terminal.
	*/
	static void dump_tx_descriptor_queue(struct eth_device *dev)
	{
	struct ep93xx_priv *priv = GET_PRIV(dev);
	int i;

	printf("\ndump_tx_descriptor_queue()\n");
	printf(" descriptor address word1 word2\n");
	for (i = 0; i < NUMTXDESC; i++) {
	printf(" [ %p ] %08X %08X\n",
	priv->tx_dq.base + i,
	(priv->tx_dq.base + i)->word1,
	(priv->tx_dq.base + i)->word2);
	}
	}

	/**
	* Dump all TX status queue entries to the terminal.
	*/
	static void dump_tx_status_queue(struct eth_device *dev)
	{
	struct ep93xx_priv *priv = GET_PRIV(dev);
	int i;

	printf("\ndump_tx_status_queue()\n");
	printf(" descriptor address word1\n");
	for (i = 0; i < NUMTXDESC; i++) {
	printf(" [ %p ] %08X\n",
	priv->rx_sq.base + i,
	(priv->rx_sq.base + i)->word1);
	}
	}
	#else
	#define dump_dev(x)
	#define dump_rx_descriptor_queue(x)
	#define dump_rx_status_queue(x)
	#define dump_tx_descriptor_queue(x)
	#define dump_tx_status_queue(x)
	#endif /* defined(EP93XX_MAC_DEBUG) */

	/**
	* Reset the EP93xx MAC by twiddling the soft reset bit and spinning until
	* it's cleared.
	*/
	static void ep93xx_mac_reset(struct eth_device *dev)
	{
	struct mac_regs *mac = GET_REGS(dev);
	uint32_t value;

	debug("+ep93xx_mac_reset");

	value = readl(&mac->selfctl);
	value \|= SELFCTL_RESET;
	writel(value, &mac->selfctl);

	while (readl(&mac->selfctl) & SELFCTL_RESET)
	; /* noop */

	debug("-ep93xx_mac_reset");
	}

	/* Eth device open */
	static int ep93xx_eth_open(struct eth_device dev, bd_t bd)
	{
	struct ep93xx_priv *priv = GET_PRIV(dev);
	struct mac_regs *mac = GET_REGS(dev);
	uchar *mac_addr = dev->enetaddr;
	int i;

	debug("+ep93xx_eth_open");

	/* Reset the MAC */
	ep93xx_mac_reset(dev);

	/* Reset the descriptor queues' current and end address values */
	priv->tx_dq.current = priv->tx_dq.base;
	priv->tx_dq.end = (priv->tx_dq.base + NUMTXDESC);

	priv->tx_sq.current = priv->tx_sq.base;
	priv->tx_sq.end = (priv->tx_sq.base + NUMTXDESC);

	priv->rx_dq.current = priv->rx_dq.base;
	priv->rx_dq.end = (priv->rx_dq.base + NUMRXDESC);

	priv->rx_sq.current = priv->rx_sq.base;
	priv->rx_sq.end = (priv->rx_sq.base + NUMRXDESC);

	/*
	* Set the transmit descriptor and status queues' base address,
	* current address, and length registers. Set the maximum frame
	* length and threshold. Enable the transmit descriptor processor.
	*/
	writel((uint32_t)priv->tx_dq.base, &mac->txdq.badd);
	writel((uint32_t)priv->tx_dq.base, &mac->txdq.curadd);
	writel(sizeof(struct tx_descriptor) * NUMTXDESC, &mac->txdq.blen);

	writel((uint32_t)priv->tx_sq.base, &mac->txstsq.badd);
	writel((uint32_t)priv->tx_sq.base, &mac->txstsq.curadd);
	writel(sizeof(struct tx_status) * NUMTXDESC, &mac->txstsq.blen);

	writel(0x00040000, &mac->txdthrshld);
	writel(0x00040000, &mac->txststhrshld);

	writel((TXSTARTMAX << 0) \| (PKTSIZE_ALIGN << 16), &mac->maxfrmlen);
	writel(BMCTL_TXEN, &mac->bmctl);

	/*
	* Set the receive descriptor and status queues' base address,
	* current address, and length registers. Enable the receive
	* descriptor processor.
	*/
	writel((uint32_t)priv->rx_dq.base, &mac->rxdq.badd);
	writel((uint32_t)priv->rx_dq.base, &mac->rxdq.curadd);
	writel(sizeof(struct rx_descriptor) * NUMRXDESC, &mac->rxdq.blen);

	writel((uint32_t)priv->rx_sq.base, &mac->rxstsq.badd);
	writel((uint32_t)priv->rx_sq.base, &mac->rxstsq.curadd);
	writel(sizeof(struct rx_status) * NUMRXDESC, &mac->rxstsq.blen);

	writel(0x00040000, &mac->rxdthrshld);

	writel(BMCTL_RXEN, &mac->bmctl);

	writel(0x00040000, &mac->rxststhrshld);

	/* Wait until the receive descriptor processor is active */
	while (!(readl(&mac->bmsts) & BMSTS_RXACT))
	; /* noop */

	/*
	* Initialize the RX descriptor queue. Clear the TX descriptor queue.
	* Clear the RX and TX status queues. Enqueue the RX descriptor and
	* status entries to the MAC.
	*/
	for (i = 0; i < NUMRXDESC; i++) {
	/* set buffer address */
	(priv->rx_dq.base + i)->word1 = (uint32_t)NetRxPackets[i];

	/* set buffer length, clear buffer index and NSOF */
	(priv->rx_dq.base + i)->word2 = PKTSIZE_ALIGN;
	}

	memset(priv->tx_dq.base, 0,
	(sizeof(struct tx_descriptor) * NUMTXDESC));
	memset(priv->rx_sq.base, 0,
	(sizeof(struct rx_status) * NUMRXDESC));
	memset(priv->tx_sq.base, 0,
	(sizeof(struct tx_status) * NUMTXDESC));

	writel(NUMRXDESC, &mac->rxdqenq);
	writel(NUMRXDESC, &mac->rxstsqenq);

	/* Set the primary MAC address */
	writel(AFP_IAPRIMARY, &mac->afp);
	writel(mac_addr[0] \| (mac_addr[1] << 8) \|
	(mac_addr[2] << 16) \| (mac_addr[3] << 24),
	&mac->indad);
	writel(mac_addr[4] \| (mac_addr[5] << 8), &mac->indad_upper);

	/* Turn on RX and TX */
	writel(RXCTL_IA0 \| RXCTL_BA \| RXCTL_SRXON \|
	RXCTL_RCRCA \| RXCTL_MA, &mac->rxctl);
	writel(TXCTL_STXON, &mac->txctl);

	/* Dump data structures if we're debugging */
	dump_dev(dev);
	dump_rx_descriptor_queue(dev);
	dump_rx_status_queue(dev);
	dump_tx_descriptor_queue(dev);
	dump_tx_status_queue(dev);

	debug("-ep93xx_eth_open");

	return 1;
	}

	/**
	* Halt EP93xx MAC transmit and receive by clearing the TxCTL and RxCTL
	* registers.
	*/
	static void ep93xx_eth_close(struct eth_device *dev)
	{
	struct mac_regs *mac = GET_REGS(dev);

	debug("+ep93xx_eth_close");

	writel(0x00000000, &mac->rxctl);
	writel(0x00000000, &mac->txctl);

	debug("-ep93xx_eth_close");
	}

	/**
	* Copy a frame of data from the MAC into the protocol layer for further
	* processing.
	*/
	static int ep93xx_eth_rcv_packet(struct eth_device *dev)
	{
	struct mac_regs *mac = GET_REGS(dev);
	struct ep93xx_priv *priv = GET_PRIV(dev);
	int len = -1;

	debug("+ep93xx_eth_rcv_packet");

	if (RX_STATUS_RFP(priv->rx_sq.current)) {
	if (RX_STATUS_RWE(priv->rx_sq.current)) {
	/*
	* We have a good frame. Extract the frame's length
	* from the current rx_status_queue entry, and copy
	* the frame's data into NetRxPackets[] of the
	* protocol stack. We track the total number of
	* bytes in the frame (nbytes_frame) which will be
	* used when we pass the data off to the protocol
	* layer via NetReceive().
	*/
	len = RX_STATUS_FRAME_LEN(priv->rx_sq.current);

	NetReceive((uchar *)priv->rx_dq.current->word1, len);

	debug("reporting %d bytes...\n", len);
	} else {
	/* Do we have an erroneous packet? */
	error("packet rx error, status %08X %08X",
	priv->rx_sq.current->word1,
	priv->rx_sq.current->word2);
	dump_rx_descriptor_queue(dev);
	dump_rx_status_queue(dev);
	}

	/*
	* Clear the associated status queue entry, and
	* increment our current pointers to the next RX
	* descriptor and status queue entries (making sure
	* we wrap properly).
	*/
	memset((void *)priv->rx_sq.current, 0,
	sizeof(struct rx_status));

	priv->rx_sq.current++;
	if (priv->rx_sq.current >= priv->rx_sq.end)
	priv->rx_sq.current = priv->rx_sq.base;

	priv->rx_dq.current++;
	if (priv->rx_dq.current >= priv->rx_dq.end)
	priv->rx_dq.current = priv->rx_dq.base;

	/*
	* Finally, return the RX descriptor and status entries
	* back to the MAC engine, and loop again, checking for
	* more descriptors to process.
	*/
	writel(1, &mac->rxdqenq);
	writel(1, &mac->rxstsqenq);
	} else {
	len = 0;
	}

	debug("-ep93xx_eth_rcv_packet %d", len);
	return len;
	}

	/**
	* Send a block of data via ethernet.
	*/
	static int ep93xx_eth_send_packet(struct eth_device *dev,
	void * const packet, int const length)
	{
	struct mac_regs *mac = GET_REGS(dev);
	struct ep93xx_priv *priv = GET_PRIV(dev);
	int ret = -1;

	debug("+ep93xx_eth_send_packet");

	/* Parameter check */
	BUG_ON(packet == NULL);

	/*
	* Initialize the TX descriptor queue with the new packet's info.
	* Clear the associated status queue entry. Enqueue the packet
	* to the MAC for transmission.
	*/

	/* set buffer address */
	priv->tx_dq.current->word1 = (uint32_t)packet;

	/* set buffer length and EOF bit */
	priv->tx_dq.current->word2 = length \| TX_DESC_EOF;

	/* clear tx status */
	priv->tx_sq.current->word1 = 0;

	/* enqueue the TX descriptor */
	writel(1, &mac->txdqenq);

	/* wait for the frame to become processed */
	while (!TX_STATUS_TXFP(priv->tx_sq.current))
	; /* noop */

	if (!TX_STATUS_TXWE(priv->tx_sq.current)) {
	error("packet tx error, status %08X",
	priv->tx_sq.current->word1);
	dump_tx_descriptor_queue(dev);
	dump_tx_status_queue(dev);

	/* TODO: Add better error handling? */
	goto eth_send_out;
	}

	ret = 0;
	/* Fall through */

	eth_send_out:
	debug("-ep93xx_eth_send_packet %d", ret);
	return ret;
	}

	#if defined(CONFIG_MII)
	int ep93xx_miiphy_initialize(bd_t * const bd)
	{
	miiphy_register("ep93xx_eth0", ep93xx_miiphy_read, ep93xx_miiphy_write);
	return 0;
	}
	#endif

	/**
	* Initialize the EP93xx MAC. The MAC hardware is reset. Buffers are
	* allocated, if necessary, for the TX and RX descriptor and status queues,
	* as well as for received packets. The EP93XX MAC hardware is initialized.
	* Transmit and receive operations are enabled.
	*/
	int ep93xx_eth_initialize(u8 dev_num, int base_addr)
	{
	int ret = -1;
	struct eth_device *dev;
	struct ep93xx_priv *priv;

	debug("+ep93xx_eth_initialize");

	priv = malloc(sizeof(*priv));
	if (!priv) {
	error("malloc() failed");
	goto eth_init_failed_0;
	}
	memset(priv, 0, sizeof(*priv));

	priv->regs = (struct mac_regs *)base_addr;

	priv->tx_dq.base = calloc(NUMTXDESC,
	sizeof(struct tx_descriptor));
	if (priv->tx_dq.base == NULL) {
	error("calloc() failed");
	goto eth_init_failed_1;
	}

	priv->tx_sq.base = calloc(NUMTXDESC,
	sizeof(struct tx_status));
	if (priv->tx_sq.base == NULL) {
	error("calloc() failed");
	goto eth_init_failed_2;
	}

	priv->rx_dq.base = calloc(NUMRXDESC,
	sizeof(struct rx_descriptor));
	if (priv->rx_dq.base == NULL) {
	error("calloc() failed");
	goto eth_init_failed_3;
	}

	priv->rx_sq.base = calloc(NUMRXDESC,
	sizeof(struct rx_status));
	if (priv->rx_sq.base == NULL) {
	error("calloc() failed");
	goto eth_init_failed_4;
	}

	dev = malloc(sizeof *dev);
	if (dev == NULL) {
	error("malloc() failed");
	goto eth_init_failed_5;
	}
	memset(dev, 0, sizeof *dev);

	dev->iobase = base_addr;
	dev->priv = priv;
	dev->init = ep93xx_eth_open;
	dev->halt = ep93xx_eth_close;
	dev->send = ep93xx_eth_send_packet;
	dev->recv = ep93xx_eth_rcv_packet;

	sprintf(dev->name, "ep93xx_eth-%hu", dev_num);

	eth_register(dev);

	/* Done! */
	ret = 1;
	goto eth_init_done;

	eth_init_failed_5:
	free(priv->rx_sq.base);
	/* Fall through */

	eth_init_failed_4:
	free(priv->rx_dq.base);
	/* Fall through */

	eth_init_failed_3:
	free(priv->tx_sq.base);
	/* Fall through */

	eth_init_failed_2:
	free(priv->tx_dq.base);
	/* Fall through */

	eth_init_failed_1:
	free(priv);
	/* Fall through */

	eth_init_failed_0:
	/* Fall through */

	eth_init_done:
	debug("-ep93xx_eth_initialize %d", ret);
	return ret;
	}

	#if defined(CONFIG_MII)

	/**
	* Maximum MII address we support
	*/
	#define MII_ADDRESS_MAX 31

	/**
	* Maximum MII register address we support
	*/
	#define MII_REGISTER_MAX 31

	/**
	* Read a 16-bit value from an MII register.
	*/
	static int ep93xx_miiphy_read(const char * const dev, unsigned char const addr,
	unsigned char const reg, unsigned short * const value)
	{
	struct mac_regs mac = (struct mac_regs )MAC_BASE;
	int ret = -1;
	uint32_t self_ctl;

	debug("+ep93xx_miiphy_read");

	/* Parameter checks */
	BUG_ON(dev == NULL);
	BUG_ON(addr > MII_ADDRESS_MAX);
	BUG_ON(reg > MII_REGISTER_MAX);
	BUG_ON(value == NULL);

	/*
	* Save the current SelfCTL register value. Set MAC to suppress
	* preamble bits. Wait for any previous MII command to complete
	* before issuing the new command.
	*/
	self_ctl = readl(&mac->selfctl);
	#if defined(CONFIG_MII_SUPPRESS_PREAMBLE)
	writel(self_ctl & ~(1 << 8), &mac->selfctl);
	#endif /* defined(CONFIG_MII_SUPPRESS_PREAMBLE) */

	while (readl(&mac->miists) & MIISTS_BUSY)
	; /* noop */

	/*
	* Issue the MII 'read' command. Wait for the command to complete.
	* Read the MII data value.
	*/
	writel(MIICMD_OPCODE_READ \| ((uint32_t)addr << 5) \| (uint32_t)reg,
	&mac->miicmd);
	while (readl(&mac->miists) & MIISTS_BUSY)
	; /* noop */

	*value = (unsigned short)readl(&mac->miidata);

	/* Restore the saved SelfCTL value and return. */
	writel(self_ctl, &mac->selfctl);

	ret = 0;
	/* Fall through */

	debug("-ep93xx_miiphy_read");
	return ret;
	}

	/**
	* Write a 16-bit value to an MII register.
	*/
	static int ep93xx_miiphy_write(const char * const dev, unsigned char const addr,
	unsigned char const reg, unsigned short const value)
	{
	struct mac_regs mac = (struct mac_regs )MAC_BASE;
	int ret = -1;
	uint32_t self_ctl;

	debug("+ep93xx_miiphy_write");

	/* Parameter checks */
	BUG_ON(dev == NULL);
	BUG_ON(addr > MII_ADDRESS_MAX);
	BUG_ON(reg > MII_REGISTER_MAX);

	/*
	* Save the current SelfCTL register value. Set MAC to suppress
	* preamble bits. Wait for any previous MII command to complete
	* before issuing the new command.
	*/
	self_ctl = readl(&mac->selfctl);
	#if defined(CONFIG_MII_SUPPRESS_PREAMBLE)
	writel(self_ctl & ~(1 << 8), &mac->selfctl);
	#endif /* defined(CONFIG_MII_SUPPRESS_PREAMBLE) */

	while (readl(&mac->miists) & MIISTS_BUSY)
	; /* noop */

	/* Issue the MII 'write' command. Wait for the command to complete. */
	writel((uint32_t)value, &mac->miidata);
	writel(MIICMD_OPCODE_WRITE \| ((uint32_t)addr << 5) \| (uint32_t)reg,
	&mac->miicmd);
	while (readl(&mac->miists) & MIISTS_BUSY)
	; /* noop */

	/* Restore the saved SelfCTL value and return. */
	writel(self_ctl, &mac->selfctl);

	ret = 0;
	/* Fall through */

	debug("-ep93xx_miiphy_write");
	return ret;
	}
	#endif /* defined(CONFIG_MII) */