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  •  * (C) Copyright 2003-2010
    
     * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
     *
     * Derived from the MPC8xx FEC driver.
     * Adapted for MPC512x by Grzegorz Bernacki <gjb@semihalf.com>
     */
    
    #include <common.h>
    #include <malloc.h>
    #include <net.h>
    
    #include <miiphy.h>
    
    #include "mpc512x_fec.h"
    
    
    DECLARE_GLOBAL_DATA_PTR;
    
    #define DEBUG 0
    
    
    #if !(defined(CONFIG_MII) || defined(CONFIG_CMD_MII))
    
    #error "CONFIG_MII has to be defined!"
    #endif
    
    
    int fec512x_miiphy_read(const char *devname, u8 phyAddr, u8 regAddr, u16 * retVal);
    int fec512x_miiphy_write(const char *devname, u8 phyAddr, u8 regAddr, u16 data);
    
    int mpc512x_fec_init_phy(struct eth_device *dev, bd_t * bis);
    
    
    static uchar rx_buff[FEC_BUFFER_SIZE];
    
    /********************************************************************/
    #if (DEBUG & 0x2)
    static void mpc512x_fec_phydump (char *devname)
    {
    
    	u16 phyStatus, i;
    	u8 phyAddr = CONFIG_PHY_ADDR;
    	u8 reg_mask[] = {
    
    		/* regs to print: 0...8, 21,27,31 */
    		1, 1, 1, 1,  1, 1, 1, 1,     1, 0, 0, 0,  0, 0, 0, 0,
    		0, 0, 0, 0,  0, 1, 0, 0,     0, 0, 0, 1,  0, 0, 0, 1,
    	};
    
    	for (i = 0; i < 32; i++) {
    		if (reg_mask[i]) {
    			miiphy_read (devname, phyAddr, i, &phyStatus);
    			printf ("Mii reg %d: 0x%04x\n", i, phyStatus);
    		}
    	}
    }
    #endif
    
    /********************************************************************/
    static int mpc512x_fec_bd_init (mpc512x_fec_priv *fec)
    {
    	int ix;
    
    	/*
    	 * Receive BDs init
    	 */
    	for (ix = 0; ix < FEC_RBD_NUM; ix++) {
    
    		fec->bdBase->rbd[ix].dataPointer =
    
    				(u32)&fec->bdBase->recv_frames[ix];
    
    		fec->bdBase->rbd[ix].status = FEC_RBD_EMPTY;
    		fec->bdBase->rbd[ix].dataLength = 0;
    	}
    
    	/*
    	 * have the last RBD to close the ring
    	 */
    	fec->bdBase->rbd[ix - 1].status |= FEC_RBD_WRAP;
    	fec->rbdIndex = 0;
    
    	/*
    	 * Trasmit BDs init
    	 */
    	for (ix = 0; ix < FEC_TBD_NUM; ix++) {
    
    		fec->bdBase->tbd[ix].status = 0;
    	}
    
    	/*
    	 * Have the last TBD to close the ring
    	 */
    	fec->bdBase->tbd[ix - 1].status |= FEC_TBD_WRAP;
    
    	/*
    	 * Initialize some indices
    	 */
    	fec->tbdIndex = 0;
    	fec->usedTbdIndex = 0;
    	fec->cleanTbdNum = FEC_TBD_NUM;
    
    
    	return 0;
    }
    
    /********************************************************************/
    static void mpc512x_fec_rbd_clean (mpc512x_fec_priv *fec, volatile FEC_RBD * pRbd)
    {
    	/*
    	 * Reset buffer descriptor as empty
    	 */
    	if ((fec->rbdIndex) == (FEC_RBD_NUM - 1))
    		pRbd->status = (FEC_RBD_WRAP | FEC_RBD_EMPTY);
    	else
    		pRbd->status = FEC_RBD_EMPTY;
    
    	pRbd->dataLength = 0;
    
    	/*
    	 * Increment BD count
    	 */
    	fec->rbdIndex = (fec->rbdIndex + 1) % FEC_RBD_NUM;
    
    	/*
    	 * Now, we have an empty RxBD, notify FEC
    
    	 * Set Descriptor polling active
    
    	out_be32(&fec->eth->r_des_active, 0x01000000);
    
    }
    
    /********************************************************************/
    static void mpc512x_fec_tbd_scrub (mpc512x_fec_priv *fec)
    {
    	volatile FEC_TBD *pUsedTbd;
    
    #if (DEBUG & 0x1)
    	printf ("tbd_scrub: fec->cleanTbdNum = %d, fec->usedTbdIndex = %d\n",
    		fec->cleanTbdNum, fec->usedTbdIndex);
    #endif
    
    	/*
    	 * process all the consumed TBDs
    	 */
    	while (fec->cleanTbdNum < FEC_TBD_NUM) {
    		pUsedTbd = &fec->bdBase->tbd[fec->usedTbdIndex];
    		if (pUsedTbd->status & FEC_TBD_READY) {
    #if (DEBUG & 0x20)
    			printf ("Cannot clean TBD %d, in use\n", fec->usedTbdIndex);
    #endif
    			return;
    		}
    
    		/*
    		 * clean this buffer descriptor
    		 */
    		if (fec->usedTbdIndex == (FEC_TBD_NUM - 1))
    			pUsedTbd->status = FEC_TBD_WRAP;
    		else
    			pUsedTbd->status = 0;
    
    		/*
    		 * update some indeces for a correct handling of the TBD ring
    		 */
    		fec->cleanTbdNum++;
    		fec->usedTbdIndex = (fec->usedTbdIndex + 1) % FEC_TBD_NUM;
    	}
    }
    
    /********************************************************************/
    
    static void mpc512x_fec_set_hwaddr (mpc512x_fec_priv *fec, unsigned char *mac)
    
    	u8 currByte;			/* byte for which to compute the CRC */
    
    	int byte;			/* loop - counter */
    	int bit;			/* loop - counter */
    
    	u32 crc = 0xffffffff;		/* initial value */
    
    
    	/*
    	 * The algorithm used is the following:
    	 * we loop on each of the six bytes of the provided address,
    	 * and we compute the CRC by left-shifting the previous
    	 * value by one position, so that each bit in the current
    	 * byte of the address may contribute the calculation. If
    	 * the latter and the MSB in the CRC are different, then
    	 * the CRC value so computed is also ex-ored with the
    	 * "polynomium generator". The current byte of the address
    	 * is also shifted right by one bit at each iteration.
    	 * This is because the CRC generatore in hardware is implemented
    	 * as a shift-register with as many ex-ores as the radixes
    	 * in the polynomium. This suggests that we represent the
    	 * polynomiumm itself as a 32-bit constant.
    	 */
    	for (byte = 0; byte < 6; byte++) {
    		currByte = mac[byte];
    		for (bit = 0; bit < 8; bit++) {
    			if ((currByte & 0x01) ^ (crc & 0x01)) {
    				crc >>= 1;
    				crc = crc ^ 0xedb88320;
    			} else {
    				crc >>= 1;
    			}
    			currByte >>= 1;
    		}
    	}
    
    	crc = crc >> 26;
    
    	/*
    	 * Set individual hash table register
    	 */
    	if (crc >= 32) {
    
    		out_be32(&fec->eth->iaddr1, (1 << (crc - 32)));
    		out_be32(&fec->eth->iaddr2, 0);
    
    		out_be32(&fec->eth->iaddr1, 0);
    		out_be32(&fec->eth->iaddr2, (1 << crc));
    
    	out_be32(&fec->eth->paddr1, (mac[0] << 24) + (mac[1] << 16) +
    				    (mac[2] <<  8) + mac[3]);
    	out_be32(&fec->eth->paddr2, (mac[4] << 24) + (mac[5] << 16) +
    				     0x8808);
    
    }
    
    /********************************************************************/
    static int mpc512x_fec_init (struct eth_device *dev, bd_t * bis)
    {
    	mpc512x_fec_priv *fec = (mpc512x_fec_priv *)dev->priv;
    
    #if (DEBUG & 0x1)
    	printf ("mpc512x_fec_init... Begin\n");
    #endif
    
    
    	mpc512x_fec_set_hwaddr (fec, dev->enetaddr);
    	out_be32(&fec->eth->gaddr1, 0x00000000);
    	out_be32(&fec->eth->gaddr2, 0x00000000);
    
    	mpc512x_fec_init_phy (dev, bis);
    
    
    	/* Set interrupt mask register */
    
    	out_be32(&fec->eth->imask, 0x00000000);
    
    
    	/* Clear FEC-Lite interrupt event register(IEVENT) */
    
    	out_be32(&fec->eth->ievent, 0xffffffff);
    
    
    	/* Set transmit fifo watermark register(X_WMRK), default = 64 */
    
    	out_be32(&fec->eth->x_wmrk, 0x0);
    
    
    	/* Set Opcode/Pause Duration Register */
    
    	out_be32(&fec->eth->op_pause, 0x00010020);
    
    	/* Frame length=1522; MII mode */
    
    	out_be32(&fec->eth->r_cntrl, (FEC_MAX_FRAME_LEN << 16) | 0x24);
    
    
    	/* Half-duplex, heartbeat disabled */
    
    	out_be32(&fec->eth->x_cntrl, 0x00000000);
    
    
    	/* Enable MIB counters */
    
    	out_be32(&fec->eth->mib_control, 0x0);
    
    
    	/* Setup recv fifo start and buff size */
    
    	out_be32(&fec->eth->r_fstart, 0x500);
    	out_be32(&fec->eth->r_buff_size, FEC_BUFFER_SIZE);
    
    
    	/* Setup BD base addresses */
    
    	out_be32(&fec->eth->r_des_start, (u32)fec->bdBase->rbd);
    	out_be32(&fec->eth->x_des_start, (u32)fec->bdBase->tbd);
    
    	out_be32(&fec->eth->dma_control, 0xc0000000);
    
    	setbits_be32(&fec->eth->ecntrl, 0x00000006);
    
    
    	/* Initilize addresses and status words of BDs */
    	mpc512x_fec_bd_init (fec);
    
    
    	 /* Descriptor polling active */
    
    	out_be32(&fec->eth->r_des_active, 0x01000000);
    
    
    #if (DEBUG & 0x1)
    	printf("mpc512x_fec_init... Done \n");
    #endif
    	return 1;
    }
    
    /********************************************************************/
    int mpc512x_fec_init_phy (struct eth_device *dev, bd_t * bis)
    {
    	mpc512x_fec_priv *fec = (mpc512x_fec_priv *)dev->priv;
    
    	const u8 phyAddr = CONFIG_PHY_ADDR;	/* Only one PHY */
    
    	int timeout = 1;
    
    	u16 phyStatus;
    
    
    #if (DEBUG & 0x1)
    	printf ("mpc512x_fec_init_phy... Begin\n");
    #endif
    
    	/*
    	 * Clear FEC-Lite interrupt event register(IEVENT)
    	 */
    
    	out_be32(&fec->eth->ievent, 0xffffffff);
    
    
    	/*
    	 * Set interrupt mask register
    	 */
    
    	out_be32(&fec->eth->imask, 0x00000000);
    
    
    	if (fec->xcv_type != SEVENWIRE) {
    		/*
    		 * Set MII_SPEED = (1/(mii_speed * 2)) * System Clock
    		 * and do not drop the Preamble.
    		 */
    
    		out_be32(&fec->eth->mii_speed,
    
    			 (((gd->arch.ips_clk / 1000000) / 5) + 1) << 1);
    
    
    		/*
    		 * Reset PHY, then delay 300ns
    		 */
    		miiphy_write (dev->name, phyAddr, 0x0, 0x8000);
    		udelay (1000);
    
    		if (fec->xcv_type == MII10) {
    		/*
    		 * Force 10Base-T, FDX operation
    		 */
    #if (DEBUG & 0x2)
    			printf ("Forcing 10 Mbps ethernet link... ");
    #endif
    			miiphy_read (dev->name, phyAddr, 0x1, &phyStatus);
    
    			miiphy_write (dev->name, phyAddr, 0x0, 0x0180);
    
    			timeout = 20;
    			do {    /* wait for link status to go down */
    				udelay (10000);
    				if ((timeout--) == 0) {
    #if (DEBUG & 0x2)
    					printf ("hmmm, should not have waited...");
    #endif
    					break;
    				}
    				miiphy_read (dev->name, phyAddr, 0x1, &phyStatus);
    #if (DEBUG & 0x2)
    				printf ("=");
    #endif
    			} while ((phyStatus & 0x0004)); /* !link up */
    
    			timeout = 1000;
    			do {    /* wait for link status to come back up */
    				udelay (10000);
    				if ((timeout--) == 0) {
    					printf ("failed. Link is down.\n");
    					break;
    				}
    				miiphy_read (dev->name, phyAddr, 0x1, &phyStatus);
    #if (DEBUG & 0x2)
    				printf ("+");
    #endif
    			} while (!(phyStatus & 0x0004)); /* !link up */
    
    #if (DEBUG & 0x2)
    			printf ("done.\n");
    #endif
    
    		} else {	/* MII100 */
    
    			/*
    			 * Set the auto-negotiation advertisement register bits
    			 */
    			miiphy_write (dev->name, phyAddr, 0x4, 0x01e1);
    
    			/*
    			 * Set MDIO bit 0.12 = 1(&& bit 0.9=1?) to enable auto-negotiation
    			 */
    			miiphy_write (dev->name, phyAddr, 0x0, 0x1200);
    
    			/*
    			 * Wait for AN completion
    			 */
    
    			do {
    				udelay (1000);
    
    				if ((timeout--) == 0) {
    #if (DEBUG & 0x2)
    					printf ("PHY auto neg 0 failed...\n");
    #endif
    					return -1;
    				}
    
    				if (miiphy_read (dev->name, phyAddr, 0x1, &phyStatus) != 0) {
    #if (DEBUG & 0x2)
    					printf ("PHY auto neg 1 failed 0x%04x...\n", phyStatus);
    #endif
    					return -1;
    				}
    			} while (!(phyStatus & 0x0004));
    
    #if (DEBUG & 0x2)
    			printf ("PHY auto neg complete! \n");
    #endif
    		}
    	}
    
    #if (DEBUG & 0x2)
    	if (fec->xcv_type != SEVENWIRE)
    		mpc512x_fec_phydump (dev->name);
    #endif
    
    #if (DEBUG & 0x1)
    	printf ("mpc512x_fec_init_phy... Done \n");
    #endif
    	return 1;
    }
    
    /********************************************************************/
    static void mpc512x_fec_halt (struct eth_device *dev)
    {
    	mpc512x_fec_priv *fec = (mpc512x_fec_priv *)dev->priv;
    	int counter = 0xffff;
    
    #if (DEBUG & 0x2)
    	if (fec->xcv_type != SEVENWIRE)
    		mpc512x_fec_phydump (dev->name);
    #endif
    
    	/*
    	 * mask FEC chip interrupts
    	 */
    
    	out_be32(&fec->eth->imask, 0);
    
    
    	/*
    	 * issue graceful stop command to the FEC transmitter if necessary
    	 */
    
    	setbits_be32(&fec->eth->x_cntrl, 0x00000001);
    
    
    	/*
    	 * wait for graceful stop to register
    	 */
    
    	while ((counter--) && (!(in_be32(&fec->eth->ievent) & 0x10000000)))
    		;
    
    
    	/*
    	 * Disable the Ethernet Controller
    	 */
    
    	clrbits_be32(&fec->eth->ecntrl, 0x00000002);
    
    
    	/*
    	 * Issue a reset command to the FEC chip
    	 */
    
    	setbits_be32(&fec->eth->ecntrl, 0x1);
    
    
    	/*
    	 * wait at least 16 clock cycles
    	 */
    	udelay (10);
    #if (DEBUG & 0x3)
    	printf ("Ethernet task stopped\n");
    #endif
    }
    
    /********************************************************************/
    
    
    static int mpc512x_fec_send(struct eth_device *dev, void *eth_data,
    			    int data_length)
    
    {
    	/*
    	 * This routine transmits one frame.  This routine only accepts
    	 * 6-byte Ethernet addresses.
    	 */
    	mpc512x_fec_priv *fec = (mpc512x_fec_priv *)dev->priv;
    	volatile FEC_TBD *pTbd;
    
    #if (DEBUG & 0x20)
    	printf("tbd status: 0x%04x\n", fec->tbdBase[fec->tbdIndex].status);
    #endif
    
    	/*
    	 * Clear Tx BD ring at first
    	 */
    	mpc512x_fec_tbd_scrub (fec);
    
    	/*
    	 * Check for valid length of data.
    	 */
    	if ((data_length > 1500) || (data_length <= 0)) {
    		return -1;
    	}
    
    	/*
    	 * Check the number of vacant TxBDs.
    	 */
    	if (fec->cleanTbdNum < 1) {
    #if (DEBUG & 0x20)
    		printf ("No available TxBDs ...\n");
    #endif
    		return -1;
    	}
    
    	/*
    	 * Get the first TxBD to send the mac header
    	 */
    	pTbd = &fec->bdBase->tbd[fec->tbdIndex];
    	pTbd->dataLength = data_length;
    
    	pTbd->dataPointer = (u32)eth_data;
    
    	pTbd->status |= FEC_TBD_LAST | FEC_TBD_TC | FEC_TBD_READY;
    	fec->tbdIndex = (fec->tbdIndex + 1) % FEC_TBD_NUM;
    
    	/* Activate transmit Buffer Descriptor polling */
    
    	out_be32(&fec->eth->x_des_active, 0x01000000);
    
    
    #if (DEBUG & 0x8)
    	printf ( "+" );
    #endif
    
    	fec->cleanTbdNum -= 1;
    
    	/*
    	 * wait until frame is sent .
    	 */
    	while (pTbd->status & FEC_TBD_READY) {
    		udelay (10);
    #if (DEBUG & 0x8)
    		printf ("TDB status = %04x\n", pTbd->status);
    #endif
    	}
    
    	return 0;
    }
    
    
    /********************************************************************/
    static int mpc512x_fec_recv (struct eth_device *dev)
    {
    	/*
    	 * This command pulls one frame from the card
    	 */
    	mpc512x_fec_priv *fec = (mpc512x_fec_priv *)dev->priv;
    	volatile FEC_RBD *pRbd = &fec->bdBase->rbd[fec->rbdIndex];
    	unsigned long ievent;
    
    
    #if (DEBUG & 0x1)
    	printf ("mpc512x_fec_recv %d Start...\n", fec->rbdIndex);
    #endif
    #if (DEBUG & 0x8)
    	printf( "-" );
    #endif
    
    	/*
    	 * Check if any critical events have happened
    	 */
    
    	ievent = in_be32(&fec->eth->ievent);
    	out_be32(&fec->eth->ievent, ievent);
    
    	if (ievent & 0x20060000) {
    		/* BABT, Rx/Tx FIFO errors */
    		mpc512x_fec_halt (dev);
    		mpc512x_fec_init (dev, NULL);
    		return 0;
    	}
    	if (ievent & 0x80000000) {
    		/* Heartbeat error */
    
    		setbits_be32(&fec->eth->x_cntrl, 0x00000001);
    
    	}
    	if (ievent & 0x10000000) {
    		/* Graceful stop complete */
    
    		if (in_be32(&fec->eth->x_cntrl) & 0x00000001) {
    
    			mpc512x_fec_halt (dev);
    
    			clrbits_be32(&fec->eth->x_cntrl, 0x00000001);;
    
    			mpc512x_fec_init (dev, NULL);
    		}
    	}
    
    	if (!(pRbd->status & FEC_RBD_EMPTY)) {
    
    		if (!(pRbd->status & FEC_RBD_ERR) &&
    
    			((pRbd->dataLength - 4) > 14)) {
    
    			/*
    			 * Get buffer size
    			 */
    
    			if (pRbd->status & FEC_RBD_LAST)
    				frame_length = pRbd->dataLength - 4;
    			else
    				frame_length = pRbd->dataLength;
    
    #if (DEBUG & 0x20)
    			{
    				int i;
    
    				printf ("recv data length 0x%08x data hdr: ",
    					pRbd->dataLength);
    
    				for (i = 0; i < 14; i++)
    
    					printf ("%x ", *((u8*)pRbd->dataPointer + i));
    
    				printf("\n");
    			}
    #endif
    			/*
    			 *  Fill the buffer and pass it to upper layers
    			 */
    
    			memcpy (&rx_buff[rx_buff_idx], (void*)pRbd->dataPointer,
    				frame_length - rx_buff_idx);
    			rx_buff_idx = frame_length;
    
    			if (pRbd->status & FEC_RBD_LAST) {
    				NetReceive ((uchar*)rx_buff, frame_length);
    				rx_buff_idx = 0;
    			}
    
    		}
    
    		/*
    		 * Reset buffer descriptor as empty
    		 */
    		mpc512x_fec_rbd_clean (fec, pRbd);
    	}
    
    	/* Try to fill Buffer Descriptors */
    
    	out_be32(&fec->eth->r_des_active, 0x01000000);
    
    
    }
    
    /********************************************************************/
    int mpc512x_fec_initialize (bd_t * bis)
    {
    
    	volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
    
    	mpc512x_fec_priv *fec;
    	struct eth_device *dev;
    	void * bd;
    
    	fec = (mpc512x_fec_priv *) malloc (sizeof(*fec));
    	dev = (struct eth_device *) malloc (sizeof(*dev));
    	memset (dev, 0, sizeof *dev);
    
    
    
    # ifndef CONFIG_FEC_10MBIT
    	fec->xcv_type = MII100;
    # else
    	fec->xcv_type = MII10;
    # endif
    	dev->priv = (void *)fec;
    
    	dev->iobase = (int)&im->fec;
    
    	dev->init = mpc512x_fec_init;
    	dev->halt = mpc512x_fec_halt;
    	dev->send = mpc512x_fec_send;
    	dev->recv = mpc512x_fec_recv;
    
    
    	sprintf (dev->name, "FEC");
    
    	eth_register (dev);
    
    
    #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
    
    	miiphy_register (dev->name,
    			fec512x_miiphy_read, fec512x_miiphy_write);
    #endif
    
    	/* Clean up space FEC's MIB and FIFO RAM ...*/
    
    	memset ((void *)&im->fec.mib,  0x00, sizeof(im->fec.mib));
    	memset ((void *)&im->fec.fifo, 0x00, sizeof(im->fec.fifo));
    
    	 * Malloc space for BDs  (must be quad word-aligned)
    
    	 * this pointer is lost, so cannot be freed
    
    	 */
    	bd = malloc (sizeof(mpc512x_buff_descs) + 0x1f);
    
    	fec->bdBase = (mpc512x_buff_descs*)((u32)bd & 0xfffffff0);
    
    	memset ((void *) bd, 0x00, sizeof(mpc512x_buff_descs) + 0x1f);
    
    	/*
    	 * Set interrupt mask register
    	 */
    
    	out_be32(&fec->eth->imask, 0x00000000);
    
    
    	/*
    	 * Clear FEC-Lite interrupt event register(IEVENT)
    	 */
    
    	out_be32(&fec->eth->ievent, 0xffffffff);
    
    
    	return 1;
    }
    
    /* MII-interface related functions */
    /********************************************************************/
    
    int fec512x_miiphy_read(const char *devname, u8 phyAddr, u8 regAddr, u16 *retVal)
    
    	volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
    	volatile fec512x_t *eth = &im->fec;
    
    	u32 reg;		/* convenient holder for the PHY register */
    	u32 phy;		/* convenient holder for the PHY */
    
    	int timeout = 0xffff;
    
    	/*
    	 * reading from any PHY's register is done by properly
    	 * programming the FEC's MII data register.
    	 */
    	reg = regAddr << FEC_MII_DATA_RA_SHIFT;
    	phy = phyAddr << FEC_MII_DATA_PA_SHIFT;
    
    
    	out_be32(&eth->mii_data, FEC_MII_DATA_ST |
    				 FEC_MII_DATA_OP_RD |
    				 FEC_MII_DATA_TA |
    				 phy | reg);
    
    
    	/*
    	 * wait for the related interrupt
    	 */
    
    	while ((timeout--) && (!(in_be32(&eth->ievent) & 0x00800000)))
    		;
    
    
    	if (timeout == 0) {
    #if (DEBUG & 0x2)
    		printf ("Read MDIO failed...\n");
    #endif
    		return -1;
    	}
    
    	/*
    	 * clear mii interrupt bit
    	 */
    
    	out_be32(&eth->ievent, 0x00800000);
    
    
    	/*
    	 * it's now safe to read the PHY's register
    	 */
    
    	*retVal = (u16) in_be32(&eth->mii_data);
    
    
    	return 0;
    }
    
    /********************************************************************/
    
    int fec512x_miiphy_write(const char *devname, u8 phyAddr, u8 regAddr, u16 data)
    
    	volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
    	volatile fec512x_t *eth = &im->fec;
    
    	u32 reg;		/* convenient holder for the PHY register */
    	u32 phy;		/* convenient holder for the PHY */
    
    	int timeout = 0xffff;
    
    	reg = regAddr << FEC_MII_DATA_RA_SHIFT;
    	phy = phyAddr << FEC_MII_DATA_PA_SHIFT;
    
    
    	out_be32(&eth->mii_data, FEC_MII_DATA_ST |
    				 FEC_MII_DATA_OP_WR |
    				 FEC_MII_DATA_TA |
    				 phy | reg | data);
    
    
    	/*
    	 * wait for the MII interrupt
    	 */
    
    	while ((timeout--) && (!(in_be32(&eth->ievent) & 0x00800000)))
    		;
    
    
    	if (timeout == 0) {
    #if (DEBUG & 0x2)
    		printf ("Write MDIO failed...\n");
    #endif
    		return -1;
    	}
    
    	/*
    	 * clear MII interrupt bit
    	 */
    
    	out_be32(&eth->ievent, 0x00800000);