lan91c96.c

介绍lan91c96芯片的驱动程序

	if (numPages > 7) {
		printf ("%s: Far too big packet error. \n", SMC_DEV_NAME);
		return 0;
	}

	/* now, try to allocate the memory */
   setenv("START TO SEND");
	SMC_SELECT_BANK (2);
	SMC_outw (LAN91C96_MMUCR_ALLOC_TX | numPages, LAN91C96_MMU);
   
  again:
	try++;
	time_out = MEMORY_WAIT_TIME;
	do {
		status = SMC_inb (LAN91C96_INT_STATS);
		if (status & LAN91C96_IST_ALLOC_INT) {

			SMC_outb (LAN91C96_IST_ALLOC_INT, LAN91C96_INT_STATS);
			break;
		}
	} while (--time_out);

	if (!time_out) {
		PRINTK2 ("%s: memory allocation, try %d failed ...\n",
				 SMC_DEV_NAME, try);
		setenv("MEM ALLOC TIMEOUT");
		if (try < SMC_ALLOC_MAX_TRY)
			goto again;
		else
			return 0;
	}

	PRINTK2 ("%s: memory allocation, try %d succeeded ...\n",
			 SMC_DEV_NAME, try);

	/* I can send the packet now.. */
	setenv(" I can send the packet now");

	ioaddr = SMC_BASE_ADDRESS;

	buf = (byte *) packet;

	/* If I get here, I _know_ there is a packet slot waiting for me */
	packet_no = SMC_inb (LAN91C96_ARR);
	if (packet_no & LAN91C96_ARR_FAILED) {
		/* or isn't there?  BAD CHIP! */
		printf ("%s: Memory allocation failed. \n", SMC_DEV_NAME);
		return 0;
	}

	/* we have a packet address, so tell the card to use it */
	SMC_outb (packet_no, LAN91C96_PNR);

	/* point to the beginning of the packet */
	SMC_outw (LAN91C96_PTR_AUTO_INCR, LAN91C96_POINTER);

	PRINTK3 ("%s: Trying to xmit packet of length %x\n",
			 SMC_DEV_NAME, length);

#if SMC_DEBUG > 2
	printf ("Transmitting Packet\n");
	print_packet (buf, length);
#endif

	/* send the packet length ( +6 for status, length and ctl byte )
	   and the status word ( set to zeros ) */
#ifdef USE_32_BIT
	SMC_outl ((length + 6) << 16, LAN91C96_DATA_HIGH);
#else
	SMC_outw (0, LAN91C96_DATA_HIGH);
	/* send the packet length ( +6 for status words, length, and ctl */
	SMC_outw ((length + 6), LAN91C96_DATA_HIGH);
#endif /* USE_32_BIT */

	/* send the actual data
	 * I _think_ it's faster to send the longs first, and then
	 * mop up by sending the last word.  It depends heavily
	 * on alignment, at least on the 486.  Maybe it would be
	 * a good idea to check which is optimal?  But that could take
	 * almost as much time as is saved?
	 */
	 setenv("SEND THE ACTUAL DATA");
#ifdef USE_32_BIT
	SMC_outsl (LAN91C96_DATA_HIGH, buf, length >> 2);
	if (length & 0x2)
		SMC_outw (*((word *) (buf + (length & 0xFFFFFFFC))),
				  LAN91C96_DATA_HIGH);
#else
	SMC_outsw (LAN91C96_DATA_HIGH, buf, (length) >> 1);
#endif /* USE_32_BIT */

	/* Send the last byte, if there is one.   */
	if ((length & 1) == 0) {
		SMC_outw (0, LAN91C96_DATA_HIGH);
	} else {
		SMC_outw (buf[length - 1] | 0x2000, LAN91C96_DATA_HIGH);
	}

	/* and let the chipset deal with it */
	SMC_outw (LAN91C96_MMUCR_ENQUEUE, LAN91C96_MMU);

	/* poll for TX INT */
	if (poll4int (LAN91C96_MSK_TX_INT, SMC_TX_TIMEOUT)) {
		/* sending failed */
		PRINTK2 ("%s: TX timeout, sending failed...\n", SMC_DEV_NAME);

		/* release packet */
		SMC_outw (LAN91C96_MMUCR_RELEASE_TX, LAN91C96_MMU);

		/* wait for MMU getting ready (low) */
		while (SMC_inw (LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY) {
			udelay (10);
		}

		PRINTK2 ("MMU ready\n");
		setenv("MMU READY");


		return 0;
	} else {
		/* ack. int */
		SMC_outw (LAN91C96_IST_TX_INT, LAN91C96_INT_STATS);

		PRINTK2 ("%s: Sent packet of length %d \n", SMC_DEV_NAME, length);

		/* release packet */
		SMC_outw (LAN91C96_MMUCR_RELEASE_TX, LAN91C96_MMU);

		/* wait for MMU getting ready (low) */
		while (SMC_inw (LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY) {
			udelay (10);
		}

		PRINTK2 ("MMU ready\n");
	}
	setenv("ACK.INT");

	return length;
}

/*-------------------------------------------------------------------------
 * smc_destructor( struct net_device * dev )
 *   Input parameters:
 *	dev, pointer to the device structure
 *
 *   Output:
 *	None.
 *--------------------------------------------------------------------------
 */
void smc_destructor ()
{
	PRINTK2 (CARDNAME ":smc_destructor\n");
}


/*
 * Open and Initialize the board
 *
 * Set up everything, reset the card, etc ..
 *
 */
static int smc_open ()
{
	int i;			/* used to set hw ethernet address */

	PRINTK2 ("%s:smc_open\n", SMC_DEV_NAME);

	/* reset the hardware */

	smc_reset ();
	smc_enable ();

	SMC_SELECT_BANK (1);

	for (i = 0; i < 6; i += 2) {
		word address;

		address = smc_mac_addr[i + 1] << 8;
		address |= smc_mac_addr[i];
		SMC_outw (address, LAN91C96_IA0 + i);
	}
	return 0;
}

/*-------------------------------------------------------------
 *
 * smc_rcv -  receive a packet from the card
 *
 * There is ( at least ) a packet waiting to be read from
 * chip-memory.
 *
 * o Read the status
 * o If an error, record it
 * o otherwise, read in the packet
 *-------------------------------------------------------------
 */
static int smc_rcv ()
{
	int packet_number;
	word status;
	word packet_length;
	int is_error = 0;

#ifdef USE_32_BIT
	dword stat_len;
#endif

	setenv("START SMC_RCV");

	SMC_SELECT_BANK (2);
	packet_number = SMC_inw (LAN91C96_FIFO);

	if (packet_number & LAN91C96_FIFO_RXEMPTY) {
		setenv("NO THINGS TO RX");

		return 0;
	}

	PRINTK3 ("%s:smc_rcv\n", SMC_DEV_NAME);
	/*  start reading from the start of the packet */
	SMC_outw (LAN91C96_PTR_READ | LAN91C96_PTR_RCV |
			  LAN91C96_PTR_AUTO_INCR, LAN91C96_POINTER);

	/* First two words are status and packet_length */
#ifdef USE_32_BIT
	stat_len = SMC_inl (LAN91C96_DATA_HIGH);
	status = stat_len & 0xffff;
	packet_length = stat_len >> 16;
#else
	status = SMC_inw (LAN91C96_DATA_HIGH);
	packet_length = SMC_inw (LAN91C96_DATA_HIGH);
#endif

	packet_length &= 0x07ff;	/* mask off top bits */

	PRINTK2 ("RCV: STATUS %4x LENGTH %4x\n", status, packet_length);

	if (!(status & FRAME_FILTER)) {
		/* Adjust for having already read the first two words */
		packet_length -= 4;		/*4; */


		/* set odd length for bug in LAN91C111, */
		/* which never sets RS_ODDFRAME */
		/* TODO ? */


#ifdef USE_32_BIT
		PRINTK3 (" Reading %d dwords (and %d bytes) \n",
			 packet_length >> 2, packet_length & 3);
		/* QUESTION:  Like in the TX routine, do I want
		   to send the DWORDs or the bytes first, or some
		   mixture.  A mixture might improve already slow PIO
		   performance  */
		SMC_insl (LAN91C96_DATA_HIGH, NetRxPackets[0], packet_length >> 2);
		/* read the left over bytes */
		if (packet_length & 3) {
			int i;

			byte *tail = (byte *) (NetRxPackets[0] + (packet_length & ~3));
			dword leftover = SMC_inl (LAN91C96_DATA_HIGH);

			for (i = 0; i < (packet_length & 3); i++)
				*tail++ = (byte) (leftover >> (8 * i)) & 0xff;
		}
#else
		PRINTK3 (" Reading %d words and %d byte(s) \n",
				 (packet_length >> 1), packet_length & 1);
		SMC_insw (LAN91C96_DATA_HIGH, NetRxPackets[0], packet_length >> 1);

#endif /* USE_32_BIT */

#if	SMC_DEBUG > 2
		printf ("Receiving Packet\n");
		print_packet (NetRxPackets[0], packet_length);
#endif
	} else {
		/* error ... */
		/* TODO ? */
		is_error = 1;
	}
	setenv("get receive");

	while (SMC_inw (LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY)
		udelay (1);		/* Wait until not busy */

	/*  error or good, tell the card to get rid of this packet */
	SMC_outw (LAN91C96_MMUCR_RELEASE_RX, LAN91C96_MMU);

	while (SMC_inw (LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY)
		udelay (1);		/* Wait until not busy */

	if (!is_error) {
		/* Pass the packet up to the protocol layers. */
		NetReceive (NetRxPackets[0], packet_length);
		setenv("receive success");
		return packet_length;
		
	} else {
	   setenv("receive o");
		return 0;
	}

}

/*----------------------------------------------------
 * smc_close
 *
 * this makes the board clean up everything that it can
 * and not talk to the outside world.   Caused by
 * an 'ifconfig ethX down'
 *
 -----------------------------------------------------*/
static int smc_close ()
{
	PRINTK2 ("%s:smc_close\n", SMC_DEV_NAME);

	/* clear everything */
	smc_shutdown ();

	return 0;
}

#if SMC_DEBUG > 2
static void print_packet (byte * buf, int length)
{
#if 0
	int i;
	int remainder;
	int lines;

	printf ("Packet of length %d \n", length);

	lines = length / 16;
	remainder = length % 16;

	for (i = 0; i < lines; i++) {
		int cur;

		for (cur = 0; cur < 8; cur++) {
			byte a, b;

			a = *(buf++);
			b = *(buf++);
			printf ("%02x%02x ", a, b);
		}
		printf ("\n");
	}
	for (i = 0; i < remainder / 2; i++) {
		byte a, b;

		a = *(buf++);
		b = *(buf++);
		printf ("%02x%02x ", a, b);
	}
	printf ("\n");
#endif /* 0 */
}
#endif /* SMC_DEBUG > 2 */

int eth_init (bd_t * bd)
{
	smc_open ();
	return 0;
}

void eth_halt ()
{
	smc_close ();
}

int eth_rx ()
{   setenv("GO INTO ETH_RX");
	return smc_rcv ();
}

int eth_send (volatile void *packet, int length)
{   setenv("GO INTO ETH_SEND");
	return smc_send_packet (packet, length);
}

int eth_hw_init ()
{
	return smc_hw_init ();
}

/*-------------------------------------------------------------------------
 * smc_hw_init()
 *
 *   Function:
 *      Reset and enable the device, check if the I/O space location
 *      is correct
 *
 *   Input parameters:
 *      None
 *
 *   Output:
 *	0 --> success
 *	1 --> error
 *--------------------------------------------------------------------------
 */
static int smc_hw_init ()
{
	unsigned short status_test;

	/* The attribute register of the LAN91C96 is located at address
	   0x0e000000 on the lubbock platform */
	volatile unsigned *attaddr = (unsigned *) (0x0e000000);

	/* first reset, then enable the device. Sequence is critical */
	attaddr[LAN91C96_ECOR] |= LAN91C96_ECOR_SRESET;
	udelay (100);
	attaddr[LAN91C96_ECOR] &= ~LAN91C96_ECOR_SRESET;
	attaddr[LAN91C96_ECOR] |= LAN91C96_ECOR_ENABLE;

	/* force 16-bit mode */
	attaddr[LAN91C96_ECSR] &= ~LAN91C96_ECSR_IOIS8;
	udelay (100);

	/* check if the I/O address is correct, the upper byte of the
	   bank select register should read 0x33 */

	status_test = SMC_inw (LAN91C96_BANK_SELECT);
	if ((status_test & 0xFF00) != 0x3300) {
		printf ("Failed to initialize ethernetchip\n");
		return 1;
	}
	return 0;
}

#endif /* COMMANDS & CFG_NET */

#endif /* CONFIG_DRIVER_LAN91C96 */