diff options
Diffstat (limited to 'drivers/net/mpc512x_fec.c')
| -rw-r--r-- | drivers/net/mpc512x_fec.c | 794 | 
1 files changed, 794 insertions, 0 deletions
| diff --git a/drivers/net/mpc512x_fec.c b/drivers/net/mpc512x_fec.c new file mode 100644 index 000000000..7caeeda65 --- /dev/null +++ b/drivers/net/mpc512x_fec.c @@ -0,0 +1,794 @@ +/* + * (C) Copyright 2003-2007 + * 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 <mpc512x.h> +#include <malloc.h> +#include <net.h> +#include <miiphy.h> +#include "mpc512x_fec.h" + +DECLARE_GLOBAL_DATA_PTR; + +#define DEBUG 0 + +#if defined(CONFIG_CMD_NET) && defined(CONFIG_NET_MULTI) && \ +	defined(CONFIG_MPC512x_FEC) + +#if !(defined(CONFIG_MII) || defined(CONFIG_CMD_MII)) +#error "CONFIG_MII has to be defined!" +#endif + +#if (DEBUG & 0x40) +static uint32 local_crc32(char *string, unsigned int crc_value, int len); +#endif + +int fec512x_miiphy_read(char *devname, uint8 phyAddr, uint8 regAddr, uint16 * retVal); +int fec512x_miiphy_write(char *devname, uint8 phyAddr, uint8 regAddr, uint16 data); +int mpc512x_fec_init_phy(struct eth_device *dev, bd_t * bis); + +static uchar rx_buff[FEC_BUFFER_SIZE]; +static int rx_buff_idx = 0; + +/********************************************************************/ +#if (DEBUG & 0x2) +static void mpc512x_fec_phydump (char *devname) +{ +	uint16 phyStatus, i; +	uint8 phyAddr = CONFIG_PHY_ADDR; +	uint8 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 = (uint32)&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 +	 */ +	fec->eth->r_des_active = 0x01000000;	/* Descriptor polling active */ +} + +/********************************************************************/ +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, char *mac) +{ +	uint8 currByte;			/* byte for which to compute the CRC */ +	int byte;			/* loop - counter */ +	int bit;			/* loop - counter */ +	uint32 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) { +		fec->eth->iaddr1 = (1 << (crc - 32)); +		fec->eth->iaddr2 = 0; +	} else { +		fec->eth->iaddr1 = 0; +		fec->eth->iaddr2 = (1 << crc); +	} + +	/* +	 * Set physical address +	 */ +	fec->eth->paddr1 = (mac[0] << 24) + (mac[1] << 16) + (mac[2] << 8) + mac[3]; +	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 + +	/* Set interrupt mask register */ +	fec->eth->imask = 0x00000000; + +	/* Clear FEC-Lite interrupt event register(IEVENT) */ +	fec->eth->ievent = 0xffffffff; + +	/* Set transmit fifo watermark register(X_WMRK), default = 64 */ +	fec->eth->x_wmrk = 0x0; + +	/* Set Opcode/Pause Duration Register */ +	fec->eth->op_pause = 0x00010020; + +	/* Frame length=1522; MII mode */ +	fec->eth->r_cntrl = (FEC_MAX_FRAME_LEN << 16) | 0x24; + +	/* Half-duplex, heartbeat disabled */ +	fec->eth->x_cntrl = 0x00000000; + +	/* Enable MIB counters */ +	fec->eth->mib_control = 0x0; + +	/* Setup recv fifo start and buff size */ +	fec->eth->r_fstart = 0x500; +	fec->eth->r_buff_size = FEC_BUFFER_SIZE; + +	/* Setup BD base addresses */ +	fec->eth->r_des_start = (uint32)fec->bdBase->rbd; +	fec->eth->x_des_start = (uint32)fec->bdBase->tbd; + +	/* DMA Control */ +	fec->eth->dma_control = 0xc0000000; + +	/* Enable FEC */ +	fec->eth->ecntrl |= 0x00000006; + +	/* Initilize addresses and status words of BDs */ +	mpc512x_fec_bd_init (fec); + +	 /* Descriptor polling active */ +	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 uint8 phyAddr = CONFIG_PHY_ADDR;	/* Only one PHY */ +	int timeout = 1; +	uint16 phyStatus; + +#if (DEBUG & 0x1) +	printf ("mpc512x_fec_init_phy... Begin\n"); +#endif + +	/* +	 * Clear FEC-Lite interrupt event register(IEVENT) +	 */ +	fec->eth->ievent = 0xffffffff; + +	/* +	 * Set interrupt mask register +	 */ +	fec->eth->imask = 0x00000000; + +	if (fec->xcv_type != SEVENWIRE) { +		/* +		 * Set MII_SPEED = (1/(mii_speed * 2)) * System Clock +		 * and do not drop the Preamble. +		 */ +		fec->eth->mii_speed = (((gd->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 +			 */ +			timeout = 50000; +			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 +	 */ +	fec->eth->imask = 0; + +	/* +	 * issue graceful stop command to the FEC transmitter if necessary +	 */ +	fec->eth->x_cntrl |= 0x00000001; + +	/* +	 * wait for graceful stop to register +	 */ +	while ((counter--) && (!(fec->eth->ievent & 0x10000000))) ; + +	/* +	 * Disable the Ethernet Controller +	 */ +	fec->eth->ecntrl &= 0xfffffffd; + +	/* +	 * Issue a reset command to the FEC chip +	 */ +	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, volatile 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 = (uint32)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 */ +	fec->eth->x_des_active = 0x01000000;	/* Descriptor polling active	*/ + +#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; +	int frame_length = 0; + +#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 = fec->eth->ievent; +	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 */ +		fec->eth->x_cntrl |= 0x00000001; +	} +	if (ievent & 0x10000000) { +		/* Graceful stop complete */ +		if (fec->eth->x_cntrl & 0x00000001) { +			mpc512x_fec_halt (dev); +			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 ", *((uint8*)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 */ +	fec->eth->r_des_active = 0x01000000;	/* Descriptor polling active */ +	return frame_length; +} + +/********************************************************************/ +int mpc512x_fec_initialize (bd_t * bis) +{ +	mpc512x_fec_priv *fec; +	struct eth_device *dev; +	int i; +	char *tmp, *end, env_enetaddr[6]; +	void * bd; + +	fec = (mpc512x_fec_priv *) malloc (sizeof(*fec)); +	dev = (struct eth_device *) malloc (sizeof(*dev)); +	memset (dev, 0, sizeof *dev); + +	fec->eth = (ethernet_regs *) MPC512X_FEC; + +# ifndef CONFIG_FEC_10MBIT +	fec->xcv_type = MII100; +# else +	fec->xcv_type = MII10; +# endif +	dev->priv = (void *)fec; +	dev->iobase = MPC512X_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 ETHERNET"); +	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 *) MPC512X_FEC + 0x200, 0x00, 0x400); + +	/* +	 * 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*)((uint32)bd & 0xfffffff0); +	memset ((void *) bd, 0x00, sizeof(mpc512x_buff_descs) + 0x1f); + +	/* +	 * Set interrupt mask register +	 */ +	fec->eth->imask = 0x00000000; + +	/* +	 * Clear FEC-Lite interrupt event register(IEVENT) +	 */ +	fec->eth->ievent = 0xffffffff; + +	/* +	 * Try to set the mac address now. The fec mac address is +	 * a garbage after reset. When not using fec for booting +	 * the Linux fec driver will try to work with this garbage. +	 */ +	tmp = getenv ("ethaddr"); +	if (tmp) { +		for (i=0; i<6; i++) { +			env_enetaddr[i] = tmp ? simple_strtoul (tmp, &end, 16) : 0; +			if (tmp) +				tmp = (*end) ? end+1 : end; +		} +		mpc512x_fec_set_hwaddr (fec, env_enetaddr); +		fec->eth->gaddr1 = 0x00000000; +		fec->eth->gaddr2 = 0x00000000; +	} + +	mpc512x_fec_init_phy (dev, bis); + +	return 1; +} + +/* MII-interface related functions */ +/********************************************************************/ +int fec512x_miiphy_read (char *devname, uint8 phyAddr, uint8 regAddr, uint16 * retVal) +{ +	ethernet_regs *eth = (ethernet_regs *) MPC512X_FEC; +	uint32 reg;		/* convenient holder for the PHY register */ +	uint32 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; + +	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--) && (!(eth->ievent & 0x00800000))) ; + +	if (timeout == 0) { +#if (DEBUG & 0x2) +		printf ("Read MDIO failed...\n"); +#endif +		return -1; +	} + +	/* +	 * clear mii interrupt bit +	 */ +	eth->ievent = 0x00800000; + +	/* +	 * it's now safe to read the PHY's register +	 */ +	*retVal = (uint16) eth->mii_data; + +	return 0; +} + +/********************************************************************/ +int fec512x_miiphy_write (char *devname, uint8 phyAddr, uint8 regAddr, uint16 data) +{ +	ethernet_regs *eth = (ethernet_regs *) MPC512X_FEC; +	uint32 reg;		/* convenient holder for the PHY register */ +	uint32 phy;		/* convenient holder for the PHY */ +	int timeout = 0xffff; + +	reg = regAddr << FEC_MII_DATA_RA_SHIFT; +	phy = phyAddr << FEC_MII_DATA_PA_SHIFT; + +	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--) && (!(eth->ievent & 0x00800000))) ; + +	if (timeout == 0) { +#if (DEBUG & 0x2) +		printf ("Write MDIO failed...\n"); +#endif +		return -1; +	} + +	/* +	 * clear MII interrupt bit +	 */ +	eth->ievent = 0x00800000; + +	return 0; +} + +#if (DEBUG & 0x40) +static uint32 local_crc32 (char *string, unsigned int crc_value, int len) +{ +	int i; +	char c; +	unsigned int crc, count; + +	/* +	 * crc32 algorithm +	 */ +	/* +	 * crc = 0xffffffff; * The initialized value should be 0xffffffff +	 */ +	crc = crc_value; + +	for (i = len; --i >= 0;) { +		c = *string++; +		for (count = 0; count < 8; count++) { +			if ((c & 0x01) ^ (crc & 0x01)) { +				crc >>= 1; +				crc = crc ^ 0xedb88320; +			} else { +				crc >>= 1; +			} +			c >>= 1; +		} +	} + +	/* +	 * In big endian system, do byte swaping for crc value +	 */ +	 /**/ return crc; +} +#endif	/* DEBUG */ + +#endif /* CONFIG_MPC512x_FEC */ |