Add c5471 Ethernet driver

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@423 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 1976 insertions, 0 deletions

diff --git a/nuttx/arch/arm/src/c5471/c5471_ethernet.c b/nuttx/arch/arm/src/c5471/c5471_ethernet.c
new file mode 100644
index 000000000..133c2fbb1
--- /dev/null
+++ b/nuttx/arch/arm/src/c5471/c5471_ethernet.c
@@ -0,0 +1,1976 @@
+/****************************************************************************
+ * arch/arm/src/c5471/c5471_ethernet.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Based one a C5471 Linux driver and released under this BSD license with
+ * special permisson from the copyright holder of the Linux driver:
+ * Todd Fischer, Cadenux, LLC.  Other references: "TMS320VC547x CPU and
+ * Peripherals Reference Guide," TI document spru038.pdf.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#if defined(CONFIG_NET)
+
+#include <sys/types.h>
+
+#include <time.h>
+#include <string.h>
+#include <debug.h>
+#include <wdog.h>
+#include <errno.h>
+
+#include <nuttx/irq.h>
+#include <nuttx/arch.h>
+
+#include <net/uip/uip.h>
+#include <net/uip/uip-arp.h>
+#include <net/uip/uip-arch.h>
+
+#include "chip.h"
+#include "up_internal.h"
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/* Configuration ************************************************************/
+/* CONFIG_C5471_NET_NINTERFACES determines the number of physical interfaces
+ * that will be supported.
+ */
+
+#ifndef CONFIG_C5471_NET_NINTERFACES
+# define CONFIG_C5471_NET_NINTERFACES 1
+#endif
+
+/* Timing values ************************************************************/
+/* TX poll deley = 1 seconds. CLK_TCK=number of clock ticks per second */
+
+#define C5471_WDDELAY   (1*CLK_TCK)
+#define C5471_POLLHSEC  (1*2)
+
+/* TX timeout = 1 minute */
+
+#define C5471_TXTIMEOUT (60*CLK_TCK)
+
+/* Ethernet GPIO bit settings ***********************************************/
+
+#define GPIO_CIO_MDIO         0x00004000
+#define GPIO_IO_MDCLK         0x00008000
+
+/* Ethernet interface bit settings ******************************************/
+
+/* TX descriptor, word #0 */
+
+#define EIM_TXDESC_OWN_HOST   0x80000000 /* Bit 15: Ownership bit */
+#define EIM_TXDESC_OWN_ENET   0x00000000
+#define EIM_TXDESC_WRAP_NEXT  0x40000000 /* Bit 14: Descriptor chain wrap */
+#define EIM_TXDESC_WRAP_FIRST 0x00000000
+#define EIM_TXDESC_FIF        0x20000000 /* Bit 13: First in frame */
+#define EIM_TXDESC_LIF        0x10000000 /* Bit 12: Last in frame */
+                                         /* Bits 8-11: Retry count status */
+#define EIM_TXDESC_INTRE      0x00800000 /* Bit 7: TX_IRQ int enable */
+#define EIM_TXDESC_STATUSMASK 0x007f0000 /* Bits 0-6: Status */
+#define EIM_TXDESC_RETRYERROR 0x00400000 /*   Exceed retry error */
+#define EIM_TXDESC_HEARTBEAT  0x00200000 /*   Heartbeat (SQE) */
+#define EIM_TXDESC_LCOLLISON  0x00100000 /*   Late collision error */
+#define EIM_TXDESC_COLLISION  0x00080000 /*   Collision */
+#define EIM_TXDESC_CRCERROR   0x00040000 /*   CRC error */
+#define EIM_TXDESC_UNDERRUN   0x00020000 /*   Underrun error */
+#define EIM_TXDESC_LOC        0x00010000 /*   Loss of carrier */
+
+/* Packet bytes value used for both TX and RX descriptors */
+
+#define EIM_PACKET_BYTES      0x00000040
+
+/* Count of descriptors */
+
+#define NUM_DESC_TX           32
+#define NUM_DESC_RX           64
+
+/* TX descriptor, word #1 */
+                                         /* Bit 15: reserved */
+#define EIM_TXDESC_PADCRC     0x00004000 /* Bit 14: Enable padding small frames */
+                                         /* Bits 11-13: reserved */
+#define EIM_TXDESC_BYTEMASK   0x000007ff /* Bits 0-10: Descriptor byte count */
+
+/* RX descriptor, word #0 */
+
+#define EIM_RXDESC_OWN_HOST   0x80000000 /* Bit 15: Ownership bit */
+#define EIM_RXDESC_OWN_ENET   0x00000000
+#define EIM_RXDESC_WRAP_NEXT  0x40000000 /* Bit 14: Descriptor chain wrap */
+#define EIM_RXDESC_WRAP_FIRST 0x00000000
+#define EIM_RXDESC_FIF        0x20000000 /* Bit 13: First in frame */
+#define EIM_RXDESC_LIF        0x10000000 /* Bit 12: Last in frame */
+                                         /* Bits 8-11: reserved */
+#define EIM_RXDESC_INTRE      0x00800000 /* Bit 7: RX_IRQ int enable */
+#define EIM_RXDESC_STATUSMASK 0x007f0000 /* Bits 0-6: Status */
+#define EIM_RXDESC_MISS       0x00400000 /*   Miss */
+#define EIM_RXDESC_VLAN       0x00200000 /*   VLAN */
+#define EIM_RXDESC_LFRAME     0x00100000 /*   Long frame error */
+#define EIM_RXDESC_SFRAME     0x00080000 /*   Short frame error */
+#define EIM_RXDESC_CRCERROR   0x00040000 /*   CRC error */
+#define EIM_RXDESC_OVERRUN    0x00020000 /*   Overrun error */
+#define EIM_RXDESC_ALIGN      0x00010000 /*   Non-octect align error */
+
+#define EIM_RXDESC_PADCRC     0x00004000 /* Enable padding for small frames */
+
+/* RX descriptor, word #1 */
+                                         /* Bits 11-15: reserved */
+#define EIM_RXDESC_BYTEMASK   0x000007ff /* Bits 0-10: Descriptor byte count */
+
+/* EIM_CPU_FILTER bit settings */
+                                         /* Bits 5-31: reserved */
+#define EIM_FILTER_MACLA      0x00000010 /* Bit 4: Enable logical address+multicast filtering */
+#define EIM_FILTER_LOGICAL    0x00000008 /* Bit 3: Enable ENET logical filtering */
+#define EIM_FILTER_MULTICAST  0x00000004 /* Bit 2: Enable multicast filtering */
+#define EIM_FILTER_BROADCAST  0x00000002 /* Bit 1: Enable broadcast matching */
+#define EIM_FILTER_UNICAST    0x00000001 /* Bit 0: Enable dest CPU address matching */
+
+/* EIM_CTRL bit settings */
+                                         /* Bits 16-31: Reserved */
+#define EIM_CTRL_ESM_EN       0x00008000 /* Bit 15: Ethernet state machine enable */
+                                         /* Bits 9-14: reserved */
+#define EIM_CTRL_ENET0_EN     0x00000100 /* Bit 8: Enable routing of RX packets CPU->ENET0 */
+                                         /* Bit 7: reserved */
+#define EIM_CTRL_ENET0_FLW    0x00000040 /* Bit 6: Enable ENET0 flow control RX threshold */
+#define EIM_CTRL_RXENET0_EN   0x00000020 /* Bit 5: Enable processing of ENET0 RX queue */
+#define EIM_CTRL_TXENET0_EN   0x00000010 /* Bit 4: Enable processing of ENET0 TX queue */
+                                         /* Bits 2-3: reserved */
+#define EIM_CTRL_RXCPU_EN     0x00000002 /* Bit 1: Enable processing of CPU RX queue */
+#define EIM_CTRL_TXCPU_EN     0x00000001 /* Bit 0: Enable processing of CPU TX queue */
+
+/* EIM_STATUS bit settings */
+                                         /* Bits 10-31: reserved */
+#define EIM_STATUS_CPU_TXLIF  0x00000200 /* Bit 9: Last descriptor of TX packet filled */
+#define EIM_STATUS_CPU_RXLIF  0x00000100 /* Bit 8: Last descriptor of RX queue processed */
+#define EIM_STATUS_CPU_TX     0x00000080 /* Bit 7: Descriptor filled in TX queue */
+#define EIM_STATUS_CPU_RX     0x00000040 /* Bit 6: Descriptor filled in RX queue */
+                                         /* Bits 3-5: reserved */
+#define EIM_STATUS_ENET0_ERR  0x00000004 /* Bit 2: ENET0 error interrupt */
+#define EIM_STATUS_ENET0_TX   0x00000002 /* Bit 1: ENET0 TX interrupt */
+#define EIM_STATUS_ENET0_RX   0x00000001 /* Bit 0" ENET0 RX interrupt */
+
+/* EIM_INTEN bit settings */
+
+#define EIM_INTEN_CPU_TXLIF  0x00000200 /* Bit 9: Last descriptor of TX packet filled */
+#define EIM_INTEN_CPU_RXLIF  0x00000100 /* Bit 8: Last descriptor of RX queue processed */
+#define EIM_INTEN_CPU_TX     0x00000080 /* Bit 7: Descriptor filled in TX queue */
+#define EIM_INTEN_CPU_RX     0x00000040 /* Bit 6: Descriptor filled in RX queue */
+                                         /* Bits 3-5: reserved */
+#define EIM_INTEN_ENET0_ERR  0x00000004 /* Bit 2: ENET0 error interrupt */
+#define EIM_INTEN_ENET0_TX   0x00000002 /* Bit 1: ENET0 TX interrupt */
+#define EIM_INTEN_ENET0_RX   0x00000001 /* Bit 0" ENET0 RX interrupt */
+
+/* ENET0_ADRMODE_EN bit settings */
+
+#define ENET_ADR_PROMISCUOUS  0x00000008 /* Bit 3: Enable snoop address comparison */
+#define ENET_ADR_BROADCAST    0x00000004 /* Bit 2: Enable broadcast address comparison */
+#define ENET_ADDR_LCOMPARE    0x00000001 /* Bit 1: Enable logical address comparison */
+#define ENET_ADDR_PCOMPARE    0x00000001 /* Bit 0: Enable physical address  comparison */
+
+/* ENET0_MODE bit settings */
+                                         /* Bits 16-31: reserved */
+#define ENET_MODO_FIFO_EN     0x00008000 /* Bit 15: Fifo enable */
+                                         /* Bits 8-14: reserved */
+#define ENET_MODE_RJCT_SFE    0x00000080 /* Bit 7: Reject short frames durig receive */
+#define ENET_MODE_DPNET       0x00000040 /* Bit 6: Demand priority networkd vs CSMA/CD */
+#define ENET_MODE_MWIDTH      0x00000020 /* Bit 5: Select nibble mode MII port */
+#define ENET_MODE_WRAP        0x00000010 /* Bit 4: Internal MAC loopback */
+#define ENET_MODE_FDWRAP      0x00000008 /* Bit 3: Full duplex wrap */
+#define ENET_MODE_FULLDUPLEX  0x00000004 /* Bit 2: 1:Full duplex */
+#define ENET_MODE_HALFDUPLEX  0x00000000 /*        0:Half duplex */
+                                         /* Bit 1: reserved */
+#define ENET_MODE_ENABLE      0x00000001 /* Bit 0: Port enable */
+
+/* PHY registers */
+
+#define MD_PHY_CONTROL_REG    0x00
+#define MD_PHY_MSB_REG        0x02
+#define MD_PHY_LSB_REG        0x03
+#define MD_PHY_CTRL_STAT_REG  0x17
+
+/*  Lucent LU3X31T-T64 transeiver ID */
+
+#define LU3X31_T64_PHYID      0x00437421
+
+/* PHY control register bit settings */
+
+#define MODE_AUTONEG          0x1000
+#define MODE_10MBIT_HALFDUP   0x0000
+#define MODE_10MBIT_FULLDUP   0x0100
+#define MODE_100MBIT_FULLDUP  0x2100
+#define MODE_100MBIT_HALFDUP  0x2000
+
+/* Inserts an ARM "nop" instruction */
+
+#define nop() asm("    nop");
+
+/* This is a helper pointer for accessing the contents of the Ethernet header */
+
+#define BUF ((struct uip_eth_hdr *)c5471->c_dev.d_buf)
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/* The c5471_driver_s encapsulates all state information for a single c5471
+ * hardware interface
+ */
+
+struct c5471_driver_s
+{
+  boolean c_bifup;            /* TRUE:ifup FALSE:ifdown */
+  WDOG_ID c_txpoll;           /* TX poll timer */
+  WDOG_ID c_txtimeout;        /* TX timeout timer */
+
+  /* Note: According to the C547x documentation: "The software has to maintain
+   * two pointers to the current RX-CPU and TX-CPU descriptors. At init time,
+   * they have to be set to the first descriptors of each queue, and they have
+   * to be incremented each time a descriptor ownership is give to the SWITCH".
+   */
+
+  volatile uint32 c_txcpudesc;
+  volatile uint32 c_rxcpudesc;
+
+  /* Last TX descriptor saved for error handling */
+
+  uint32 c_lastdescstart;
+  uint32 c_lastdescend;
+
+  /* Shadowed registers */
+
+  uint32 c_eimstatus;
+
+#ifdef CONFIG_C5471_NET_STATS
+  /* TX statistics */
+
+  uint32 c_txpackets;      /* Number of packets sent */
+  uint32 c_txmiss;         /* Miss */
+  uint32 c_txvlan;         /* VLAN */
+  uint32 c_txlframe;       /* Long frame errors */
+  uint32 c_txsframe;       /* Short frame errors */
+  uint32 c_txcrc;          /* CRC errors */
+  uint32 c_txoverrun;      /* Overrun errors */
+  uint32 c_txalign;        /* Non-octect align errors */
+  uint32 c_txtimeouts;     /* TX timeouts */
+
+  uint32 c_rxpackets;      /* Number of packets received */
+  uint32 c_rxretries;      /* Exceed retry errors */
+  uint32 c_rxheartbeat;    /* Heartbeat (SQE) */
+  uint32 c_rxlcollision;   /* Late collision errors */
+  uint32 c_rxcollision;    /* Collision */
+  uint32 c_rxcrc;          /* CRC errors */
+  uint32 c_rxunderrun;     /* Underrun errors */
+  uint32 c_rxloc;          /* Loss of carrier */
+#endif
+
+  /* This holds the information visible to uIP/NuttX */
+
+  struct uip_driver_s c_dev;  /* Interface understood by uIP */
+};
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static struct c5471_driver_s g_c5471[CONFIG_C5471_NET_NINTERFACES];
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/* Transceiver interface */
+
+static void c5471_mdtxbit (int bit_state);
+static int  c5471_mdrxbit (void);
+static void c5471_mdwrite (int adr, int reg, int data);
+static int  c5471_mdread (int adr, int reg);
+static int  c5471_phyinit (void);
+
+/* Support logic */
+
+static void c5471_inctxcpu(void);
+static void c5471_incrxcpu(void);
+
+/* Common TX logic */
+
+static int  c5471_transmit(struct c5471_driver_s *c5471);
+static int  c5471_uiptxpoll(struct uip_driver_s *dev);
+
+/* Interrupt handling */
+
+static void c5471_receive(struct c5471_driver_s *c5471);
+static void c5471_txdone(struct c5471_driver_s *c5471);
+static int  c5471_interrupt(int irq, FAR void *context);
+
+/* Watchdog timer expirations */
+
+static void c5471_polltimer(int argc, uint32 arg, ...);
+static void c5471_txtimeout(int argc, uint32 arg, ...);
+
+/* NuttX callback functions */
+
+static int c5471_ifup(struct uip_driver_s *dev);
+static int c5471_ifdown(struct uip_driver_s *dev);
+static int c5471_txavail(struct uip_driver_s *dev);
+
+/* Initialization functions */
+
+static void c5471_eimreset (struct c5471_driver_s *c5471);
+static void c5471_eimconfig(void);
+static void c5471_reset(struct c5471_driver_s *c5471);
+static void c5471_macassign(struct c5471_driver_s *c5471);
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: c5471_mdtxbit
+ *
+ * Description
+ *   A helper routine used when serially communicating with the c547X's
+ *   external ethernet transeiver device. GPIO pins are connected to the
+ *   transeiver's MDCLK and MDIO pins and are used to accomplish the serial
+ *   comm.
+ *
+ *   protocol:
+ *                      ___________
+ *     MDCLK   ________/           \_
+ *              ________:____
+ *     MDIO    <________:____>--------
+ *                      :
+ *                      ^
+ *              Pin state internalized
+ *
+ ****************************************************************************/
+
+static void c5471_mdtxbit (int bit_state)
+{
+  /* Note: any non-zero "bit_state" supplied by the caller means we should clk a "1"
+   * out the MDIO pin.
+   */
+
+  /* config MDIO as output pin. */
+
+  putreg32((getreg32(GPIO_CIO) & ~GPIO_CIO_MDIO), GPIO_CIO);
+  if (bit_state)
+    {
+      /* set MDIO state high. */
+
+      putreg32(getreg32(GPIO_IO) | GPIO_CIO_MDIO), GPIO_IO);
+    }
+  else
+    {
+      /* set MDIO state low. */
+
+      putreg32((getreg32(GPIO_IO) & ~GPIO_CIO_MDIO), GPIO_IO);
+    }
+
+  nop();
+  nop();
+  nop();
+  nop();
+
+  /* MDCLK rising edge */
+
+  putreg32((getreg32(GPIO_IO) | GPIO_IO_MDCLK), GPIO_IO);
+  nop();
+  nop();
+
+  /* release MDIO */
+
+  putreg32((getreg32(GPIO_CIO)|GPIO_CIO_MDIO), GPIO_CIO);
+  nop();
+  nop();
+
+  /* MDCLK falling edge. */
+
+  putreg32((getreg32(GPIO_IO) & ~GPIO_IO_MDCLK), GPIO_IO);
+}
+
+/****************************************************************************
+ * Name: c5471_mdrxbit
+ *
+ * Description
+ *    A helper routine used when serially communicating with the c547X's
+ *    external ethernet transeiver device. GPIO pins are connected to the
+ *    transeiver's MDCLK and MDIO pins and are used to accomplish the serial
+ *    comm.
+ *
+ *    protocol:
+ *                       ___________
+ *       MDCLK  ________/           \_
+ *              _______:_____
+ *       MDIO   _______:_____>--------
+ *                     :
+ *                     ^
+ *            pin state sample point
+ *
+ ****************************************************************************/
+
+static int c5471_mdrxbit (void)
+{
+  register volatile uint32 bit_state;
+
+  /* config MDIO as input pin. */
+
+  putreg32((getreg32(GPIO_CIO) | GPIO_CIO_MDIO), GPIO_CIO);
+
+  /* Make sure the MDCLK is low */
+
+  putreg32((getreg32(GPIO_IO) & ~GPIO_IO_MDCLK), GPIO_IO);
+  nop();
+  nop();
+  nop();
+  nop();
+
+  /* Sample MDIO */
+
+  bit_state = getreg32(GPIO_IO) & GPIO_CIO_MDIO;
+
+  /* MDCLK rising edge */
+
+  putreg32((getreg32(GPIO_IO)|GPIO_IO_MDCLK), GPIO_IO);
+  nop();
+  nop();
+  nop();
+  nop();
+
+  /* MDCLK falling edge. */
+
+  putreg32((getreg32(GPIO_IO)&~GPIO_IO_MDCLK), GPIO_IO); /* MDCLK falling edge */
+  if (bit_state)
+    {
+      return 1;
+    }
+  else
+    {
+      return 0;
+    }
+}
+
+/****************************************************************************
+ * Name: c5471_mdwrite
+ *
+ * Description
+ *    A helper routine used when serially communicating with the c547X's
+ *    external ethernet transeiver device. GPIO pins are connected to the
+ *    transeiver's MDCLK and MDIO pins and are used to accomplish the serial
+ *    comm.
+ *
+ ****************************************************************************/
+
+static void c5471_mdwrite (int adr, int reg, int data)
+{
+  int i;
+
+  /* preamble: 11111111111111111111111111111111 */
+
+  for (i = 0; i < 32; i++)
+    c5471_mdtxbit(1);
+
+  /* start of frame: 01 */
+
+  c5471_mdtxbit(0);
+  c5471_mdtxbit(1);
+
+  /* operation code: 01 - write */
+
+  c5471_mdtxbit(0);
+  c5471_mdtxbit(1);
+
+  /* PHY device address: AAAAA, msb first */
+
+  for (i = 0; i < 5; i++)
+    {
+      c5471_mdtxbit(adr & 0x10);
+      adr = adr << 1;
+    }
+
+  /* MII register address: RRRRR, msb first */
+
+  for (i = 0; i < 5; i++)
+    {
+      c5471_mdtxbit(reg & 0x10);
+      reg = reg << 1;
+    }
+
+  /* turnaround time: ZZ */
+
+  c5471_mdtxbit(1);
+  c5471_mdtxbit(0);
+
+  /* data: DDDDDDDDDDDDDDDD, msb first */
+
+  for (i = 0; i < 16; i++)
+    {
+      c5471_mdtxbit(data & 0x8000);
+      data = data << 1;
+    }
+}
+
+/****************************************************************************
+ * Name: c5471_mdread
+ *
+ * Description
+ *    A helper routine used when serially communicating with the c547X's
+ *    external ethernet transeiver device. GPIO pins are connected to the
+ *    transeiver's MDCLK and MDIO pins and are used to accomplish the serial
+ *    comm.
+ *
+ ****************************************************************************/
+
+static int c5471_mdread (int adr, int reg)
+{
+  int i;
+  int data = 0;
+
+  /* preamble: 11111111111111111111111111111111 */
+
+  for (i = 0; i < 32; i++)
+    c5471_mdtxbit(1);
+
+  /* start of frame: 01 */
+
+  c5471_mdtxbit(0);
+  c5471_mdtxbit(1);
+
+  /* operation code: 10 - read */
+
+  c5471_mdtxbit(1);
+  c5471_mdtxbit(0);
+
+  /* PHY device address: AAAAA, msb first */
+
+  for (i = 0; i < 5; i++)
+    {
+      c5471_mdtxbit(adr & 0x10);
+      adr = adr << 1;
+    }
+
+  /* MII register address: RRRRR, msb first */
+
+  for (i = 0; i < 5; i++)
+    {
+      c5471_mdtxbit(reg & 0x10);
+      reg = reg << 1;
+    }
+
+  /* turnaround time: ZZ */
+
+  c5471_mdrxbit();
+  c5471_mdrxbit(); /* PHY should drive a 0 */
+
+  /* data: DDDDDDDDDDDDDDDD, msb first */
+
+  for (i = 0; i < 16; i++)
+    {
+      data = data << 1;
+      data |= c5471_mdrxbit();
+    }
+
+  return data;
+}
+
+/****************************************************************************
+ * Name: c5471_phyinit
+ *
+ * Description
+ *   The c547X EVM board uses a Lucent LU3X31T-T64 transeiver device to
+ *   handle the physical layer (PHY). It's a h/w block that on the one end
+ *   offers a Media Independent Interface (MII) which is connected to the
+ *   Ethernet Interface Module (EIM) internal to the C547x and on the other
+ *   end offers either the 10baseT or 100baseT electrical interface connecting
+ *   to an RJ45 onboard network connector. The PHY transeiver has several
+ *   internal registers allowing host configuration and status access. These
+ *   internal registers are accessable by clocking serial data in/out of the
+ *   MDIO pin of the LU3X31T-T64 chip. For c547X, the MDC and the MDIO pins
+ *   are connected to the C547x GPIO15 and GPIO14 pins respectivley. Host
+ *   software twiddles the GPIO pins appropriately to get data serially into
+ *   and out of the chip. This is typically a one time operation at boot and
+ *   normal operation of the transeiver involves EIM/Transeiver interaction at
+ *   the other pins of the transeiver chip and doesn't require host intervention
+ *   at the MDC and MDIO pins.
+ *
+ ****************************************************************************/
+
+#if (CONFIG_C5471_ETHERNET_PHY == ETHERNET_PHY_LU3X31T_T64)
+static int c5471_phyinit (void)
+{
+  int phy_id;
+  int status;
+
+  /* Next, Setup GPIO pins to talk serially to the Lucent transeiver chip */
+
+  /* enable gpio bits 15,14 */
+
+  putreg32((getreg32(GPIO_EN) | 0x0000C000), GPIO_EN);
+
+  /* config gpio(15); out -> MDCLK */
+
+  putreg32((getreg32(GPIO_CIO) & ~0x00008000), GPIO_CIO);
+
+  /* config gpio(14); in <- MDIO */
+
+  putreg32((getreg32(GPIO_CIO) | 0x00004000), GPIO_CIO);
+
+  /* initial pin state; MDCLK = 0 */
+
+  putreg32((getreg32(GPIO_IO) & 0x000F3FFF), GPIO_IO);
+
+  /* Next, request a chip reset */
+
+  c5471_mdwrite(0, MD_PHY_CONTROL_REG, 0x8000); 
+  while (c5471_mdread(0, MD_PHY_CONTROL_REG) & 0x8000)
+    {
+      /* wait for chip reset to complete */
+    }
+
+  /* Next, Read out the chip ID */
+
+  phy_id = (c5471_mdread(0, MD_PHY_MSB_REG) << 16) | c5471_mdread(0, MD_PHY_LSB_REG);
+  if (phy_id != LU3X31_T64_PHYID)
+    {
+      return -1;
+    }
+
+  /* Next, Set desired network rate, 10BaseT, 100BaseT, or auto. */
+
+#ifdef CONFIG_NET_C5471_AUTONEGOTIATION
+  ndbg("Setting PHY Transceiver for Autonegotiation. (per rrload Makefile).\n");
+  c5471_mdwrite(0, MD_PHY_CONTROL_REG, MODE_AUTONEG);
+#endif 
+#ifdef CONFIG_NET_C5471_BASET100
+  ndbg("Setting PHY Transceiver for 100BaseT FullDuplex. (per rrload Makefile).\n");
+  c5471_mdwrite(0, MD_PHY_CONTROL_REG, MODE_100MBIT_FULLDUP);
+#endif 
+#ifdef CONFIG_NET_C5471_BASET10
+  ndbg("Setting PHY Transceiver for 10BaseT FullDuplex. (per rrload Makefile).\n");
+  c5471_mdwrite(0, MD_PHY_CONTROL_REG, MODE_10MBIT_FULLDUP);
+#endif 
+
+  status = c5471_mdread(0, MD_PHY_CTRL_STAT_REG);
+  return status;
+}
+
+#elif (CONFIG_C5471_ETHERNET_PHY == ETHERNET_PHY_AC101L)
+
+static int c5471_phyinit (void)
+{
+  int phy_id;
+  int status;
+
+  /* Next, Setup GPIO pins to talk serially to the Lucent transeiver chip */
+
+  putreg32((getreg32(GPIO_EN)|0x0000C000), GPIO_EN);   /* enable gpio bits 15,14 */
+  putreg32((getreg32(GPIO_CIO)&~0x00008000), GPIO_CIO); /* config gpio(15); out -> MDCLK */
+  putreg32((getreg32(GPIO_CIO)|0x00004000), GPIO_CIO);  /* config gpio(14); in <- MDIO */
+  putreg32((getreg32(GPIO_IO)&0x000F3FFF), GPIO_IO);   /* initial pin state; MDCLK = 0 */
+
+  return 1;
+}
+
+#else
+# define c5471_phyinit()
+# if !defined(CONFIG_C5471_ETHERNET_PHY)
+#  warning "CONFIG_C5471_ETHERNET_PHY not defined -- assumed NONE"
+# endif
+#endif
+
+/****************************************************************************
+ * Name: c5471_inctxcpu
+ *
+ * Description
+ *
+ ****************************************************************************/
+
+static void c5471_inctxcpu(void)
+{
+  if (EIM_TXDESC_WRAP_NEXT & getreg32(c5471->c_txcpudesc))
+    {
+      /* Loop back around to base of descriptor queue */
+
+      c5471->c_txcpudesc = (volatile uint32 *)(getreg32(EIM_CPU_TXBA) + EIM_RAM_START);
+    }
+  else
+    {
+      c5471->c_txcpudesc += 2*sizeof(uint32);
+    }
+}
+
+/****************************************************************************
+ * Name: c5471_incrxcpu
+ *
+ * Description
+ *
+ ****************************************************************************/
+
+static void c5471_incrxcpu(void)
+{
+  if (EIM_RXDESC_WRAP_NEXT & getreg32(c5471->c_rxcpudesc))
+    {
+      /* Loop back around to base of descriptor queue */
+
+      c5471->c_rxcpudesc = (volatile uint32 *)(getreg32(EIM_CPU_RXBA) + EIM_RAM_START);
+    }
+  else
+    {
+      c5471->c_rxcpudesc += 2*sizeof(uint32);
+    }
+}
+
+/****************************************************************************
+ * Function: c5471_transmit
+ *
+ * Description:
+ *   Start hardware transmission.  Called either from the txdone interrupt
+ *   handling or from watchdog based polling.
+ *
+ * Parameters:
+ *   c5471  - Reference to the driver state structure
+ *
+ * Returned Value:
+ *   OK on success; a negated errno on failure
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static int c5471_transmit(struct c5471_driver_s *c5471)
+{
+  volatile uint32 *packetmem;
+  volatile uint32 *ptr;
+  uint16 bytelen;
+  uint16 longlen;
+  boolean bfirstframe;
+  int nshorts;
+  unsigned int i;
+  unsigned int j;
+
+  j                      = 0;
+  bfirstframe            = TRUE;
+  c5471->c_lastdescstart = c5471->c_rxcpudesc;
+
+  while (nbytes)
+    {
+      /* Words #0 and #1 of descriptor */
+
+      while (EIM_TXDESC_OWN_HOST & getreg32(c5471->c_rxcpudesc))
+       {
+         /* Loop until the SWITCH lets go of the descriptor giving us access
+          * rights to submit our new ether frame to it.
+          */
+       }
+
+      if (bfirstframe)
+        {
+          putreg32((getreg32(c5471->c_rxcpudesc) | EIM_RXDESC_FIF), c5471->c_rxcpudesc);
+        }
+      else
+        {
+          putreg32((getreg32(c5471->c_rxcpudesc) & ~EIM_RXDESC_FIF), c5471->c_rxcpudesc);
+        }
+
+      putreg32((getreg32(c5471->c_rxcpudesc) & ~EIM_RXDESC_PADCRC), c5471->c_rxcpudesc);
+
+      if (bfirstframe)
+        {
+          putreg32((getreg32(c5471->c_rxcpudesc)|EIM_RXDESC_PADCRC), c5471->c_rxcpudesc);
+        }
+
+      if (nbytes >= EIM_PACKET_BYTES)
+        {
+          bytelen = EIM_PACKET_BYTES;
+        }
+      else
+        {
+          bytelen = nbytes;
+        }
+
+      /* Next, submit ether frame bytes to the C547x Ether Module packet memory space */
+
+      for (i = 0; i < longlen; i++, j++)
+        {
+        }
+
+      /* Next, submit ether frame bytes to the C5472 Ether Module packet
+       * memory space.
+       */
+
+      /* divide by 2 with round up. */
+
+      nshorts = (bytelen+1)>>1;
+
+      /* Words #2 and #3 of descriptor */
+
+      packetmem = (uint32 *)getreg32(c5471->c_rxcpudesc + sizeof(uint32));
+      for (i = 0; i < nshorts; i++, j++)
+        {
+          /* 16-bits at a time. */
+
+          packetmem[i] = __swap_16(((uint16*)buf)[j]);
+        }
+
+      putreg32(((getreg32(c5471->c_rxcpudesc) & ~EIM_RXDESC_BYTEMASK) | bytelen), c5471->c_rxcpudesc);
+      nbytes -= bytelen;
+      if (0 == nbytes)
+        {
+          putreg32((getreg32(c5471->c_rxcpudesc) | EIM_RXDESC_LIF), c5471->c_rxcpudesc);
+        }
+      else
+        {
+          putreg32((getreg32(c5471->c_rxcpudesc) & ~EIM_RXDESC_LIF), c5471->c_rxcpudesc);
+        }
+
+      /* We're done with that descriptor; give access rights back to h/w */
+
+      putreg32((getreg32(c5471->c_rxcpudesc) | EIM_RXDESC_OWN_HOST), c5471->c_rxcpudesc);
+
+      /* Next, tell Ether Module that those submitted bytes are ready for the wire */
+
+      putreg32(0x00000001, EIM_CPU_RXREADY);
+      c5471->c_lastdescend = c5471->c_rxcpudesc;
+
+      /* Advance to the next free descriptor */
+
+      c5471_incrxcpu();
+      bfirstframe = FALSE;
+    }
+  return;
+
+  /* Verify that the hardware is ready to send another packet */
+
+  /* Increment statistics */
+
+  /* Disable Ethernet interrupts */
+
+  /* Send the packet: address=c5471->c_dev.d_buf, length=c5471->c_dev.d_len */
+
+  /* Restore Ethernet interrupts */
+
+  /* Setup the TX timeout watchdog (perhaps restarting the timer) */
+
+  (void)wd_start(c5471->c_txtimeout, C5471_TXTIMEOUT, c5471_txtimeout, 1, (uint32)c5471);
+  return OK;
+}
+
+/****************************************************************************
+ * Function: c5471_uiptxpoll
+ *
+ * Description:
+ *   The transmitter is available, check if uIP has any outgoing packets ready
+ *   to send.  This is a callback from uip_poll().  uip_poll() may be called:
+ *
+ *   1. When the preceding TX packet send is complete,
+ *   2. When the preceding TX packet send timesout and the interface is reset
+ *   3. During normal TX polling
+ *
+ * Parameters:
+ *   dev  - Reference to the NuttX driver state structure
+ *
+ * Returned Value:
+ *   OK on success; a negated errno on failure
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static int c5471_uiptxpoll(struct uip_driver_s *dev)
+{
+  struct c5471_driver_s *c5471 = (struct c5471_driver_s *)dev->d_private;
+
+  /* If the polling resulted in data that should be sent out on the network,
+   * the field d_len is set to a value > 0.
+   */
+
+  if (c5471->c_dev.d_len > 0)
+    {
+      uip_arp_out(&c5471->c_dev);
+      c5471_transmit(c5471);
+
+      /* Check if the ESM has let go of the RX descriptor giving us access
+       * rights to submit another Ethernet frame.
+       */
+
+      if (EIM_TXDESC_OWN_HOST & getreg32(c5471->c_rxcpudesc) != 0)
+        {
+          /* No, then return non-zero to terminate the poll */
+
+          return 1;
+        }
+    }
+
+  /* If zero is returned, the polling will continue until all connections have
+   * been examined.
+   */
+
+  return 0;
+}
+
+/****************************************************************************
+ * Function: c5471_rxstatus
+ *
+ * Description:
+ *   An interrupt was received indicating that the last RX packet(s) is done
+ *
+ * Parameters:
+ *   c5471  - Reference to the driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_C5471_NET_STATS
+void c5471_rxstatus(int *numbytes)
+{
+  uint32 *pdesc = c5471->c_txcpudesc;
+  uint32 rxstatus;
+
+  /* Walk that last packet we just received to collect xmit status bits. */
+
+  rxstatus = 0;
+  for (;;)
+    {
+      if (EIM_TXDESC_OWN_HOST & getreg32(pdesc))
+        {
+          /* The incoming packe queue is empty. */
+
+          break;
+        }
+
+      rxstatus |= (getreg32(pdesc) & EIM_TXDESC_STATUSMASK);
+
+      if ((getreg32(pdesc) & EIM_TXDESC_LIF) != 0)
+        {
+          break;
+        }
+
+      /* This packet is made up of several descriptors, find next one in chain. */
+
+      if (EIM_TXDESC_WRAP_NEXT & getreg32(pdesc))
+        {
+          /* Loop back around to base of descriptor queue. */
+
+          pdesc = (uint32*)(getreg32(EIM_CPU_RXBA) + EIM_RAM_START);
+        }
+      else
+        {
+          pdesc += 2;
+        }
+    }
+
+  if (rxstatus != 0)
+    {
+      if ((rxstatus & EIM_TXDESC_RETRYERROR) != 0)
+        {
+          c5471->c_rxretries++;
+        }
+
+      if ((rxstatus & EIM_TXDESC_HEARTBEAT) != 0)
+        {
+          c5471->c_rxheartbeat++;
+        }
+
+      if ((rxstatus & EIM_TXDESC_LCOLLISON) != 0)
+        {
+          c5471->c_rxlcollision++;
+        }
+
+      if ((rxstatus & EIM_TXDESC_COLLISION) != 0)
+        {
+          c5471->c_rxcollision++;
+        }
+
+      if ((rxstatus & EIM_TXDESC_CRCERROR) != 0)
+        {
+          c5471->c_rxcrc++;
+        }
+
+      if ((rxstatus & EIM_TXDESC_UNDERRUN) != 0)
+        {
+          c5471->c_rxunderrun++;
+        }
+
+      if ((rxstatus & EIM_TXDESC_LOC) != 0)
+        {
+          c5471->c_rxloc++;
+        }
+    }
+}
+#endif
+
+/****************************************************************************
+ * Function: c5471_receive
+ *
+ * Description:
+ *   An interrupt was received indicating the availability of a new RX packet
+ *
+ * Parameters:
+ *   c5471  - Reference to the driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static void c5471_receive(struct c5471_driver_s *c5471)
+{
+  struct uip_driver_s *dev = c5471->c_dev;
+  uint16 *packetmem = NULL;
+  boolean bmore = TRUE;
+  int packetlen;
+  int bytelen = 0;
+  int nshorts;
+  int i;
+  int j = 0;
+
+  /* Walk the newly received packet contained within the EIM and transfer
+   * its contents to the uIP buffer. This frees up the memory contained within
+   * the EIM for additional packets that might be received later from the network.
+   */
+
+  while (bmore)
+    {
+      /* Words #0 and #1 of descriptor */
+
+      if (EIM_TXDESC_OWN_HOST & getreg32(c5471->c_txcpudesc))
+        {
+          /* No further packets to receive. */
+
+          break;
+        }
+
+      bytelen    = (getreg32(c5471->c_txcpudesc) & EIM_TXDESC_BYTEMASK);
+      packetlen += bytelen;
+
+      /* Words #2 and #3 of descriptor */
+
+      packetmem = (uint16*)getreg32(c5471->c_txcpudesc+1);
+
+      /* Divide by 2 with round up to get the number of 16-bit words. */
+
+      nshorts = (bytelen + 1) >> 1;
+      for (i = 0 ; i < nshorts; i++, j++)
+        {
+          /* Check if the received packet will fit without the uIP packet buffer */
+
+          if (packelen < (CONFIG_NET_BUFSIZE - 4))
+            {
+              /* Copy the data data from the hardware to c5471->c_dev.d_buf 16-bits at
+               * a time.
+               */
+
+              ((uint16*)dev->d_buf)[j] = __swap_16(packetmem[i]);
+            }
+        }
+
+      if (getreg32(c5471->c_txcpudesc) & EIM_TXDESC_LIF)
+        {
+          bmore = FALSE;
+        }
+
+      /* Next, Clear all bits of words0/1 of the emptied descriptor except preserve
+       * the settings of a select few. Can leave descriptor words 2/3 alone.
+       */
+
+      putreg32((getreg32(c5471->c_txcpudesc) & (EIM_TXDESC_WRAP_NEXT|EIM_TXDESC_INTRE)),
+               c5471->c_txcpudesc);
+
+      /* Next, Give ownership of now emptied descriptor back to the Ether Module's SWITCH */
+
+      putreg32((getreg32(c5471->c_txcpudesc) | EIM_TXDESC_OWN_HOST), c5471->c_txcpudesc);
+
+      /* Advance to the next data buffer */
+
+      c5471_inctxcpu();
+    }
+
+  /* Adjust the packet length to remove the CRC bytes that uIP doesn't care about. */
+
+  packetlen -= 4;
+
+
+  /* If we successfully transferred the data into the uIP buffer, then pass it on
+   * to uIP for processing.
+   */
+
+  if (packetlen > 0 && packetlen < (CONFIG_NET_BUFSIZE / sizeof(uint16)))
+    {
+      /* Set amount of data in c5471->c_dev.d_len. */
+
+      dev->d_len = packetlen;
+
+      /* We only accept IP packets of the configured type and ARP packets */
+
+#ifdef CONFIG_NET_IPv6
+      if (BUF->type == HTONS(UIP_ETHTYPE_IP6))
+#else
+      if (BUF->type == HTONS(UIP_ETHTYPE_IP))
+#endif
+        {
+          uip_arp_ipin();
+          uip_input(&c5471->c_dev);
+
+          /* If the above function invocation resulted in data that should be
+           * sent out on the network, the field  d_len will set to a value > 0.
+           * Send that data now if ESM has let go of the RX descriptor giving us
+           * access rights to submit another Ethernet frame.
+           */
+
+          if (c5471->c_dev.d_len > 0 &&
+             (EIM_TXDESC_OWN_HOST & getreg32(c5471->c_rxcpudesc)) == 0)
+            {
+              uip_arp_out(&c5471->c_dev);
+              c5471_transmit(c5471);
+            }
+        }
+      else if (BUF->type == htons(UIP_ETHTYPE_ARP))
+        {
+          uip_arp_arpin(&c5471->c_dev);
+
+          /* If the above function invocation resulted in data that should be
+           * sent out on the network, the field  d_len will set to a value > 0.
+           * Send that data now if ESM has let go of the RX descriptor giving us
+           * access rights to submit another Ethernet frame.
+           */
+
+          if (c5471->c_dev.d_len > 0 &&
+             (EIM_TXDESC_OWN_HOST & getreg32(c5471->c_rxcpudesc)) == 0)
+            {
+              c5471_transmit(c5471);
+            }
+        }
+    }
+}
+
+/****************************************************************************
+ * Function: c5471_txstatus
+ *
+ * Description:
+ *   An interrupt was received indicating that the last TX packet(s) is done
+ *
+ * Parameters:
+ *   c5471  - Reference to the driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_C5471_NET_STATS
+static inline void c5471_txstatus(void)
+{
+  uint32 *pdesc = c5471->c_lastdescstart;
+  uint32 txstatus;
+
+  /* Walk that last packet we just sent to collect xmit status bits. */
+
+  txstatus = 0;
+  if (c5471->c_lastdescstart && c5471->c_lastdescend)
+    {
+      for (;;)
+        {
+          txstatus |= (getreg32(pdesc) & EIM_TXDESC_STATUSMASK);
+          if (pdesc == c5471->c_lastdescend)
+            {
+              break;
+            }
+
+          /* This packet is made up of several descriptors, find next one in chain. */
+
+          if (EIM_RXDESC_WRAP_NEXT & getreg32(c5471->c_rxcpudesc))
+            {
+              /* Loop back around to base of descriptor queue. */
+
+              pdesc = (uint32*)(getreg32(EIM_CPU_RXBA) + EIM_RAM_START);
+            }
+          else
+            {
+              pdesc += 2;
+            }
+        }
+    }
+
+  if (txstatus)
+    {
+      if ((txstatus & EIM_RXDESC_MISS) != 0)
+        {
+          c5471->c_txmiss++;
+        }
+
+      if ((txstatus & EIM_RXDESC_VLAN) != 0)
+        {
+          c5471->c_txvlan++;
+        }
+
+      if ((txstatus & EIM_RXDESC_LFRAME) != 0)
+        {
+          c5471->c_txlframe++;
+        }
+
+      if ((txstatus & EIM_RXDESC_SFRAME) != 0)
+        {
+          c5471->c_txsframe++;
+        }
+
+      if ((txstatus & EIM_RXDESC_CRCERROR) != 0)
+        {
+          c5471->c_txcrc++;
+        }
+
+      if ((txstatus & EIM_RXDESC_OVERRUN) != 0)
+        {
+          c5471->c_txoverrun++;
+        }
+
+      if ((txstatus & EIM_RXDESC_OVERRUN) != 0)
+        {
+          c5471->c_txalign++;
+        }
+}
+#endif
+
+/****************************************************************************
+ * Function: c5471_txdone
+ *
+ * Description:
+ *   An interrupt was received indicating that the last TX packet(s) is done
+ *
+ * Parameters:
+ *   c5471  - Reference to the driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static void c5471_txdone(struct c5471_driver_s *c5471)
+{
+  /* Update statistics */
+
+#ifdef CONFIG_C5471_NET_STATS
+  c5471->c_txpackets++;
+
+  /* Check for TX errors */
+
+  c5471_txstatus(c5471);
+#endif
+
+  /* If no further xmits are pending, then cancel the TX timeout */
+
+  wd_cancel(c5471->c_txtimeout);
+
+  /* Then poll uIP for new XMIT data */
+
+  (void)uip_poll(&c5471->c_dev, c5471_uiptxpoll);
+}
+
+/****************************************************************************
+ * Function: c5471_interrupt
+ *
+ * Description:
+ *   Hardware interrupt handler
+ *
+ * Parameters:
+ *   irq     - Number of the IRQ that generated the interrupt
+ *   context - Interrupt register state save info (architecture-specific)
+ *
+ * Returned Value:
+ *   OK on success
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static int c5471_interrupt(int irq, FAR void *context)
+{
+  /* Get and clear interrupt status bits */
+
+  /* Handle interrupts according to status bit settings */
+
+  /* Check if we received an incoming packet, if so, call c5471_receive() */
+
+  c5471->c_eimstatus = getreg32(EIM_STATUS);
+  if (EIM_STATUS_CPU_TX & c5471->c_eimstatus)
+    {
+      /* An incoming packet has been received by the EIM from the network and
+       * the interrupt associated with EIM's CPU TX queue has been asserted. It
+       * is the EIM's CPU TX queue that we need to read from to get those
+       * packets.  We use this terminology to stay consistent with the Orion
+       * documentation.
+       */
+
+ #ifdef CONFIG_C5471_NET_STATS
+      /* Increment the count of received packets */
+
+      c5471->c_rxpackets++;
+
+      /* Check for RX errors */
+
+      c5471_rxstatus(c5471);
+#endif
+
+      /* Process the received packet */
+
+      c5471_receive(c5471);
+    }
+
+  /* Check is a packet transmission just completed.  If so, call c5471_txdone */
+
+  if (EIM_STATUS_CPU_RX & c5471->c_eimstatus)
+    {
+      /* An outgoing packet has been processed by the EIM and the interrupt
+       * associated with EIM's CPU RX que has been asserted. It is the EIM's
+       * CPU RX queue that we put packets on to send them *out*. TWe use this
+       * terminology to stay consistent with the Orion documentation.
+       */
+
+      c5471_txdone(c5471);
+    }
+
+  /* Enable Ethernet interrupts (perhaps excluding the TX done interrupt if 
+   * there are no pending transmissions.
+   */
+
+  return OK;
+}
+
+/****************************************************************************
+ * Function: c5471_txtimeout
+ *
+ * Description:
+ *   Our TX watchdog timed out.  Called from the timer interrupt handler.
+ *   The last TX never completed.  Reset the hardware and start again.
+ *
+ * Parameters:
+ *   argc - The number of available arguments
+ *   arg  - The first argument
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static void c5471_txtimeout(int argc, uint32 arg, ...)
+{
+  struct c5471_driver_s *c5471 = (struct c5471_driver_s *)arg;
+
+  /* Increment statistics */
+
+#ifdef CONFIG_C5471_NET_STATS
+  c5471->c_txtimeouts++;
+#endif
+
+  /* Then try to restart the hardware */
+
+  c5471_ifdown(&c5471->c_dev);
+  c5471_ifup(&c5471->c_dev);
+
+  /* Then poll uIP for new XMIT data */
+
+  (void)uip_poll(&c5471->c_dev, c5471_uiptxpoll);
+}
+
+/****************************************************************************
+ * Function: c5471_polltimer
+ *
+ * Description:
+ *   Periodic timer handler.  Called from the timer interrupt handler.
+ *
+ * Parameters:
+ *   argc - The number of available arguments
+ *   arg  - The first argument
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static void c5471_polltimer(int argc, uint32 arg, ...)
+{
+  struct c5471_driver_s *c5471 = (struct c5471_driver_s *)arg;
+
+  /* Check if the ESM has let go of the RX descriptor giving us access rights
+   * to submit another Ethernet frame.
+   */
+
+  if (EIM_TXDESC_OWN_HOST & getreg32(c5471->c_rxcpudesc) == 0)
+    {
+      /* If so, update TCP timing states and poll uIP for new XMIT data */
+
+      (void)uip_timer(&c5471->c_dev, c5471_uiptxpoll, C5471_POLLHSEC);
+    }
+
+  /* Setup the watchdog poll timer again */
+
+  (void)wd_start(c5471->c_txpoll, C5471_WDDELAY, c5471_polltimer, 1, arg);
+}
+
+/****************************************************************************
+ * Function: c5471_ifup
+ *
+ * Description:
+ *   NuttX Callback: Bring up the Ethernet interface when an IP address is
+ *   provided 
+ *
+ * Parameters:
+ *   dev  - Reference to the NuttX driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *   The user has assigned a MAC to the driver
+ *
+ ****************************************************************************/
+
+static int c5471_ifup(struct uip_driver_s *dev)
+{
+  struct c5471_driver_s *c5471 = (struct c5471_driver_s *)dev->d_private;
+  volatile uint32 clearbits;
+
+  ndbg("Bringing up: %d.%d.%d.%d\n",
+       dev->d_ipaddr & 0xff, (dev->d_ipaddr >> 8) & 0xff,
+       (dev->d_ipaddr >> 16) & 0xff, dev->d_ipaddr >> 24 );
+
+  /* Initilize Ethernet interface */
+
+  c5471_reset();
+
+  /* Assign the MAC to the device */
+
+  c5471_macassign(c5471);
+
+  /* Enable interrupts going from EIM Module to Interrupt Module. */
+
+  clearbits = eth_in32(EIM_STATUS);
+  putreg32((getreg32(EIM_INTEN) | EIM_INTEN_CPU_TX|EIM_INTEN_CPU_RX)), EIM_INTEN);
+
+  /* Next, go on-line. According to the C547X documentation the enables have to
+   * occur in this order to insure proper operation; ESM first then the ENET.
+   */
+
+  putreg32((getreg32(EIM_CTRL) | EIM_CTRL_ESM_EN), EIM_CTRL);   /* enable ESM */
+  putreg32((getreg32(ENET0_MODE) | ENET_MODE_ENABLE), ENET0_MODE); /* enable ENET */
+  up_mdelay(100);
+
+  /* Set and activate a timer process */
+
+  (void)wd_start(c5471->c_txpoll, C5471_WDDELAY, c5471_polltimer, 1, (uint32)c5471);
+
+  /* Enable the Ethernet interrupt */
+
+  c5471->c_bifup = TRUE;
+  up_enable_irq(C5471_IRQ_ETHER);
+  return OK;
+}
+
+/****************************************************************************
+ * Function: c5471_ifdown
+ *
+ * Description:
+ *   NuttX Callback: Stop the interface.
+ *
+ * Parameters:
+ *   dev  - Reference to the NuttX driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+static int c5471_ifdown(struct uip_driver_s *dev)
+{
+  struct c5471_driver_s *c5471 = (struct c5471_driver_s *)dev->d_private;
+  irqstate_t flags;
+
+  /* Disable the Ethernet interrupt */
+
+  flags = irqsave();
+  up_disable_irq(C5471_IRQ_ETHER);
+
+  /* Disable interrupts going from EIM Module to Interrupt Module. */
+
+  putreg32((getreg32(EIM_INTEN) & ~(EIM_INTEN_CPU_TX|EIM_INTEN_CPU_RX)), EIM_INTEN);
+
+  /* Disable ENET */
+
+  putreg32((getreg32(ENET0_MODE) & ~ENET_MODE_ENABLE), ENET0_MODE); /* disable ENET */
+
+  /* Disable ESM */
+
+  putreg32((getreg32(EIM_CTRL) & ~EIM_CTRL_ESM_EN), EIM_CTRL);  /* disable ESM */
+
+  /* Cancel the TX poll timer and TX timeout timers */
+
+  wd_cancel(c5471->c_txpoll);
+  wd_cancel(c5471->c_txtimeout);
+
+  /* Reset the device */
+
+  c5471->c_bifup = FALSE;
+  irqrestore(flags);
+  return OK;
+}
+
+/****************************************************************************
+ * Function: c5471_txavail
+ *
+ * Description:
+ *   Driver callback invoked when new TX data is available.  This is a 
+ *   stimulus perform an out-of-cycle poll and, thereby, reduce the TX
+ *   latency.
+ *
+ * Parameters:
+ *   dev  - Reference to the NuttX driver state structure
+ *
+ * Returned Value:
+ *   None
+ *
+ * Assumptions:
+ *   Called in normal user mode
+ *
+ ****************************************************************************/
+
+static int c5471_txavail(struct uip_driver_s *dev)
+{
+  struct c5471_driver_s *c5471 = (struct c5471_driver_s *)dev->d_private;
+  irqstate_t flags;
+
+  flags = irqsave();
+
+  /* Ignore the notification if the interface is not yet up */
+
+  if (c5471->c_bifup)
+    {
+      /* Check if the ESM has let go of the RX descriptor giving us access
+       * rights to submit another Ethernet frame.
+       */
+
+      if (EIM_TXDESC_OWN_HOST & getreg32(c5471->c_rxcpudesc) == 0)
+       {
+          /* If so, then poll uIP for new XMIT data */
+
+          (void)uip_poll(&c5471->c_dev, c5471_uiptxpoll);
+       }
+    }
+
+  irqrestore(flags);
+  return OK;
+}
+
+/****************************************************************************
+ * Name: c5471_eimreset
+ *
+ * Description
+ *   The C547x docs states that a module should generally be reset according
+ *   to the following algorithm:
+ *
+ *   1. Put the module in reset.
+ *   2. Switch on the module clock.
+ *   3. Wait for eight clock cycles.
+ *   4. Release the reset.
+ *
+ ****************************************************************************/
+
+static void c5471_eimreset (struct c5471_driver_s *c5471)
+{
+  /* Stop the EIM module clock */
+
+  putreg32((getreg32(CLKM) | CLKM_EIM_CLK_STOP), CLKM);
+
+  /* Put EIM module in reset */
+
+  putreg32((getreg32(CLKM_RESET) & ~CLKM_RESET_EIM), CLKM_RESET);
+
+  /* Start the EIM module clock */
+
+  putreg32((getreg32(CLKM) & ~CLKM_EIM_CLK_STOP), CLKM);
+
+  /* Assert nRESET to reset the board's PHY0/1 chips */
+
+  putreg32((CLKM_CTL_RST_EXT_RESET|CLKM_CTL_RST_LEAD_RESET), CLKM_CTL_RST);
+  up_mdelay(2);
+
+  /* Release the peripheral nRESET signal */
+
+  putreg32(CLKM_CTL_RST_LEAD_RESET, CLKM_CTL_RST);
+
+  /* Release EIM module reset */
+
+  putreg32((getreg32(CLKM_RESET) | CLKM_RESET_EIM), CLKM_RESET);
+
+  /* All EIM register should now be in there power-up default states */
+
+  c5471->c_lastdescstart = NULL;
+  c5471->c_lastdescend   = NULL;
+}
+
+/****************************************************************************
+ * Name: c5471_eimconfig
+ *
+ * Description
+ *    Assumes that all registers are currently in the power-up reset state.
+ *    This routine then modifies that state to provide our specific ethernet
+ *    configuration.
+ *
+ ****************************************************************************/
+
+static void c5471_eimconfig(void)
+{
+  volatile uint8  *pbuf;
+  volatile uint32 *pdesc;
+  volatile uint32 *val;
+  int i;
+
+  pdesc = EIM_RAM_START;
+  pbuf  = (uint8*)EIM_RAM_START + 0x6C0;
+
+  /* TX ENET 0 */
+
+  putreg32((((uint32)pdesc) & 0x0000ffff), ENET0_TDBA); /* 16bit offset address */
+  for (i = NUM_DESC_TX-1; i >= 0; i--)
+    {
+      if (i == 0)
+        val = EIM_TXDESC_WRAP_NEXT;
+      else
+        val = EIM_TXDESC_WRAP_FIRST;
+      val |= EIM_TXDESC_OWN_HOST|EIM_TXDESC_INTRE|EIM_TXDESC_PADCRC|EIM_PACKET_BYTES;
+      putreg32(val, pdesc);
+
+      pdesc++;
+      putreg32((uint32)pbuf, pdesc);
+
+      pdesc++;
+      *((volatile uint32 *)pbuf) = 0x00000000;
+
+      pbuf += EIM_PACKET_BYTES;
+      *((volatile uint32 *)pbuf) = 0x00000000;
+
+      /* As per c547X doc; this space for Ether Module's "Buffer Usage Word" */
+
+      pbuf += 4;
+    }
+
+  /* RX ENET 0 */
+
+  putreg32((((uint32)pdesc) & 0x0000ffff), ENET0_RDBA); /* 16bit offset address */
+  for (i = NUM_DESC_RX-1; i >= 0; i--)
+    {
+      if (i == 0)
+        val = EIM_RXDESC_WRAP_NEXT;
+      else
+        val = EIM_RXDESC_WRAP_FIRST;
+      val |= EIM_RXDESC_OWN_ENET|EIM_RXDESC_INTRE|EIM_RXDESC_PADCRC|EIM_PACKET_BYTES;
+      putreg32(val, pdesc);
+
+      pdesc++;
+      putreg32((uint32)pbuf, pdesc);
+
+      pdesc++;
+      *((uint32 *)pbuf) = 0x00000000;
+
+      pbuf += EIM_PACKET_BYTES;
+      *((uint32 *)pbuf) = 0x00000000;
+
+      /* As per c547X doc; this space for Ether Module's "Buffer Usage Word" */
+
+      pbuf += 4;
+  }
+
+  /* TX CPU */
+
+  c5471->c_txcpudesc = pdesc;
+  putreg32((((uint32)pdesc) & 0x0000ffff), EIM_CPU_TXBA); /* 16bit offset address */
+  for (i = NUM_DESC_TX-1; i >= 0; i--)
+    {
+      /* Set words 1+2 of the TXDESC */
+
+      if (i == 0)
+        val = EIM_TXDESC_WRAP_NEXT;
+      else
+        val = EIM_TXDESC_WRAP_FIRST;
+      val |= EIM_TXDESC_OWN_HOST|EIM_TXDESC_INTRE|EIM_TXDESC_PADCRC|EIM_PACKET_BYTES;
+      putreg32(val, pdesc);
+
+      pdesc++;
+      putreg32((uint32)pbuf, pdesc);
+
+      pdesc++;
+      *((uint32 *)pbuf) = 0x00000000;
+
+      pbuf += EIM_PACKET_BYTES;
+      *((uint32 *)pbuf) = 0x00000000;
+
+      /* As per C547X doc; this space for Ether Module's "Buffer Usage Word" */
+
+      pbuf += 4;
+  }
+
+  /* RX CPU */
+
+  c5471->c_rxcpudesc = pdesc;
+  putreg32((uint32)((uint32)(pdesc)&0x0000ffff), EIM_CPU_RXBA); /* 16bit offset address */
+  for (i = NUM_DESC_RX-1; i >= 0; i--)
+    {
+      /* Set words 1+2 of the RXDESC */
+
+      if (i == 0)
+        val = EIM_RXDESC_WRAP_NEXT;
+      else
+        val = EIM_RXDESC_WRAP_FIRST;
+      val |= EIM_RXDESC_OWN_ENET|EIM_RXDESC_INTRE|EIM_RXDESC_PADCRC|EIM_PACKET_BYTES;
+      putreg32(val, pdesc);
+
+      pdesc++;
+      putreg32((uint32)pbuf, pdesc);
+
+      pdesc++;
+      *((uint32 *)pbuf) = 0x0000;
+
+      pbuf += EIM_PACKET_BYTES;
+      *((uint32 *)pbuf) = 0x0000;
+
+      /* As per c547X doc; this space for Ether Module's "Buffer Usage Word" */
+
+      pbuf += 4;
+  }
+
+  /* Save the descriptor packet size */
+
+  putreg32(EIM_PACKET_BYTES, EIM_BUFSIZE);
+
+  /* Set the filter mode */
+
+#if 0
+  putreg32(EIM_FILTER_UNICAST, EIM_CPU_FILTER);
+#else
+//  putreg32(EIM_FILTER_LOGICAL|EIM_FILTER_UNICAST|EIM_FILTER_MULTICAST|
+//           EIM_FILTER_BROADCAST, EIM_CPU_FILTER);
+  putreg32(EIM_FILTER_UNICAST|EIM_FILTER_MULTICAST|EIM_FILTER_BROADCAST, EIM_CPU_FILTER);
+#endif 
+
+  /* Disable all Ethernet interrupts */
+
+  putreg32(0x00000000, EIM_INTEN);
+
+  /* Setup the EIM control register */
+
+#if 1
+  putreg32(EIM_CTRL_ENET0_EN|EIM_CTRL_RXENET0_EN|EIM_CTRL_TXENET0_EN|
+           EIM_CTRL_RXCPU_EN|EIM_CTRL_TXCPU_EN, EIM_CTRL);
+#else 
+  putreg32(EIM_CTRL_ENET0_EN|EIM_CTRL_ENET0_FLW|EIM_CTRL_RXENET0_EN|
+           EIM_CTRL_TXENET0_EN|EIM_CTRL_RXCPU_EN|EIM_CTRL_TXCPU_EN, EIM_CTRL);
+#endif
+
+#if 1 
+  putreg32(0x00000000, EIM_MFVHI);
+#else
+  putreg32(0x0000ff00, EIM_MFVHI);
+#endif 
+
+  putreg32(0x00000000, EIM_MFVLO);
+  putreg32(0x00000000, EIM_MFMHI);
+  putreg32(0x00000000, EIM_MFMLO);
+  putreg32(0x00000018, EIM_RXTH);
+  putreg32(0x00000000, EIM_CPU_RXREADY);
+
+  /* Setup the ENET0 mode register */
+
+#if 1
+  putreg32(ENET_MODE_RJCT_SFE|ENET_MODE_MWIDTH|ENET_MODE_FULLDUPLEX, ENET0_MODE);
+#else
+  putreg32(ENET_MODE_RJCT_SFE|ENET_MODE_MWIDTH|ENET_MODE_HALFDUPLEX, ENET0_MODE);
+#endif 
+
+  putreg32(0x00000000, ENET0_BOFFSEED);
+  putreg32(0x00000000, ENET0_FLWPAUSE);
+  putreg32(0x00000000, ENET0_FLWCONTROL);
+  putreg32(0x00000000, ENET0_VTYPE);
+
+#if 0 
+  putreg32(ENET_ADR_BROADCAST|ENET_ADR_PROMISCUOUS, ENET0_ADRMODE_EN);
+#else 
+  /* The CPU port is not PROMISCUOUS, it wants a no-promiscuous address
+   * match yet the the SWITCH receives packets from the PROMISCUOUS ENET0
+   * which routes all packets for filter matching at the CPU port which
+   * then allows the s/w to see the new incoming packetes that passed
+   * the filter. Here we are setting the main SWITCH closest the ether
+   * wire.
+   */
+
+  putreg32(ENET_ADR_PROMISCUOUS, ENET0_ADRMODE_EN);
+#endif 
+
+  putreg32(0x00000000, ENET0_DRP);
+  up_mdelay(500);
+}
+
+/****************************************************************************
+ * Name: c5471_reset
+ *
+ * Description
+ *
+ ****************************************************************************/
+
+static void c5471_reset(struct c5471_driver_s *c5471)
+{
+#if (CONFIG_C5471_ETHERNET_PHY == ETHERNET_PHY_LU3X31T_T64)
+  c5471_eimreset(c5471);
+#endif
+  c5471_phyinit();
+  c5471_eimconfig();
+}
+
+/****************************************************************************
+ * Name: c5471_macassign
+ *
+ * Description
+ *    Set the mac address of our CPU ether port so that when the SWITCH
+ *    receives packets from the PROMISCUOUS ENET0 it will switch them to the
+ *    CPU port and cause a packet arrival event on the Switch's CPU TX queue
+ *    when an address match occurs. The CPU port is not PROMISCUOUS and wants
+ *    to see only packets specifically addressed to this device.
+ *
+ ****************************************************************************/
+
+static void c5471_macassign(struct c5471_driver_s *c5471)
+{
+  struct uip_driver_s *dev = &c5471->s_dev;
+  register uint32 tmp;
+
+  /* Set CPU port MAC address. S/W will only see incoming packets that match
+   * this destination address.
+   */
+
+  tmp = (((uint32)dev->d_mac[0]) << 8) | ((uint32)dev->d_mac[1]);
+  putreg32(tmp, EIM_CPU_DAHI);
+
+  tmp = (((uint32)dev->d_mac[2]) << 24) | (((uint32)dev->d_mac[3]) << 16) |
+        (((uint32)dev->d_mac[4]) <<  8) |  ((uint32)dev->d_mac[5])
+  putreg32(tmp, EIM_CPU_DALO);
+
+#if 0
+  /* Set the ENET MAC address */
+
+  putreg32(getreg32(EIM_CPU_DAHI), ENET0_PARHI);
+  putreg32(getreg32(EIM_CPU_DALO), ENET0_PARLO);
+  putreg32(getreg32(EIM_CPU_DAHI), ENET0_LARHI);
+  putreg32(getreg32(EIM_CPU_DALO), ENET0_LARLO);
+
+#else
+  /* ENET MAC assignment not needed for its PROMISCUOUS mode */ 
+
+  putreg32(0x00000000, ENET0_PARHI);
+  putreg32(0x00000000, ENET0_PARLO);
+  putreg32(0x00000000, ENET0_LARHI);
+  putreg32(0x00000000, ENET0_LARLO);
+
+#endif
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Function: c5471_initialize
+ *
+ * Description:
+ *   Initialize the Ethernet driver
+ *
+ * Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   OK on success; Negated errno on failure.
+ *
+ * Assumptions:
+ *
+ ****************************************************************************/
+
+/* Initialize the DM90x0 chip and driver */
+
+int up_netinitialize(void)
+{
+  /* Attach the IRQ to the driver */
+
+  if (irq_attach(C5471_IRQ_ETHER, c5471_interrupt))
+    {
+      /* We could not attach the ISR to the ISR */
+
+      return -EAGAIN;
+    }
+
+  /* Initialize the driver structure */
+
+  memset(g_c5471, 0, CONFIG_C5471_NET_NINTERFACES*sizeof(struct c5471_driver_s));
+  g_c5471[0].c_dev.d_ifup    = c5471_ifup;     /* I/F down callback */
+  g_c5471[0].c_dev.d_ifdown  = c5471_ifdown;   /* I/F up (new IP address) callback */
+  g_c5471[0].c_dev.d_txavail = c5471_txavail;  /* New TX data callback */
+  g_c5471[0].c_dev.d_private = (void*)g_c5471; /* Used to recover private state from dev */
+
+  /* Create a watchdog for timing polling for and timing of transmisstions */
+
+  g_c5471[0].c_txpoll       = wd_create();   /* Create periodic poll timer */
+  g_c5471[0].c_txtimeout    = wd_create();   /* Create TX timeout timer */
+
+  /* Register the device with the OS so that socket IOCTLs can be performed */
+
+  (void)netdev_register(&g_c5471[0].c_dev);
+  return OK;
+}
+
+#endif /* CONFIG_NET */
+