etherelnk3.c

来自「这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易」· C语言 代码 · 共 1,849 行 · 第 1/3 页

		COMMAND(port, SelectRegisterWindow, Wdiagnostic);
		STATUS(port);
		ctlr->stats[BytesRcvdOk+2] += inb(port+BadSSD);
		break;
	}

	COMMAND(port, SelectRegisterWindow, w);
}

static void
txstart(Ether* ether)
{
	int port, len;
	Ctlr *ctlr;
	Msgbuf *mb;

	port = ether->port;
	ctlr = ether->ctlr;

	/*
	 * Attempt to top-up the transmit FIFO. If there's room simply
	 * stuff in the packet length (unpadded to a dword boundary), the
	 * packet data (padded) and remove the packet from the queue.
	 * If there's no room post an interrupt for when there is.
	 * This routine is called both from the top level and from interrupt
	 * level and expects to be called with ctlr->wlock already locked
	 * and the correct register window (Wop) in place.
	 */
	for(;;){
		if(ctlr->txmb != nil){
			mb = ctlr->txmb;
			ctlr->txmb = nil;
		}
		else{
			mb = etheroq(ether);
			if(mb == nil)
				break;
		}

		len = ROUNDUP(mb->count, 4);
		if(len+4 <= ins(port+TxFree)){
			outl(port+Fifo, mb->count);
			outsl(port+Fifo, mb->data, len/4);
			mbfree(mb);
		}
		else{
			ctlr->txmb = mb;
			if(ctlr->txbusy == 0){
				ctlr->txbusy = 1;
				COMMAND(port, SetTxAvailableThresh, len>>ctlr->ts);
			}
			break;
		}
	}
}

static void
txstart905(Ether* ether)
{
	Ctlr *ctlr;
	int port, stalled, timeo;
	Msgbuf *mb;
	Pd *pd;

	ctlr = ether->ctlr;
	port = ether->port;

	/*
	 * Free any completed packets.
	 */
	pd = ctlr->dntail;
	while(ctlr->dnq){
		if(PADDR(&pd->np) == inl(port+DnListPtr))
			break;
		if(pd->mb != nil){
			mbfree(pd->mb);
			pd->mb = nil;
		}
		ctlr->dnq--;
		pd = pd->next;
	}
	ctlr->dntail = pd;

	stalled = 0;
	while(ctlr->dnq < (ctlr->ndn-1)){
		mb = etheroq(ether);
		if(mb == nil)
			break;

		pd = ctlr->dnhead->next;
		pd->np = 0;
		pd->control = dnIndicate|mb->count;
		pd->addr = PADDR(mb->data);
		pd->len = updnLastFrag|mb->count;
		pd->mb = mb;

		if(stalled == 0 && ctlr->dnq && inl(port+DnListPtr)){
			COMMAND(port, Stall, dnStall);
			for(timeo = 100; (STATUS(port) & commandInProgress) && timeo; timeo--)
				;
			if(timeo == 0)
				print("#l%d: dnstall %d\n", ether->ctlrno, timeo);
			stalled = 1;
		}

		coherence();
		ctlr->dnhead->np = PADDR(&pd->np);
		ctlr->dnhead->control &= ~dnIndicate;
		ctlr->dnhead = pd;
		if(ctlr->dnq == 0)
			ctlr->dntail = pd;
		ctlr->dnq++;

		ctlr->dnqueued++;
	}

	if(ctlr->dnq > ctlr->dnqmax)
		ctlr->dnqmax = ctlr->dnq;

	/*
	 * If the adapter is not currently processing anything
	 * and there is something on the queue, start it processing.
	 */
	if(inl(port+DnListPtr) == 0 && ctlr->dnq)
		outl(port+DnListPtr, PADDR(&ctlr->dnhead->np));
	if(stalled)
		COMMAND(port, Stall, dnUnStall);
}

static void
transmit(Ether* ether)
{
	Ctlr *ctlr;
	int port, w;

	port = ether->port;
	ctlr = ether->ctlr;

	ilock(&ctlr->wlock);
	if(ctlr->dnenabled)
		txstart905(ether);
	else{
		w = (STATUS(port)>>13) & 0x07;
		COMMAND(port, SelectRegisterWindow, Wop);
		txstart(ether);
		COMMAND(port, SelectRegisterWindow, w);
	}
	iunlock(&ctlr->wlock);
}

static void
receive905(Ether* ether)
{
	Ctlr *ctlr;
	int len, port, q;
	Pd *pd;
	Msgbuf *mb;

	ctlr = ether->ctlr;
	port = ether->port;

	if(inl(port+UpPktStatus) & upStalled)
		ctlr->upstalls++;
	q = 0;
	for(pd = ctlr->uphead; pd->control & upPktComplete; pd = pd->next){
		if(pd->control & upError){
			if(pd->control & upOverrun)
				ether->ifc.rcverr++;
			else if(pd->control & (upOversizedFrame|upRuntFrame))
				ether->ifc.rcverr++;
			else if(pd->control & upAlignmentError)
				ether->ifc.rcverr++;
			if(pd->control & upCRCError)
				ether->ifc.sumerr++;
		}
		else if(mb = mballoc(sizeof(Enpkt)+4, 0, Mbeth1)){
			len = pd->control & rxBytes;
			pd->mb->count = len;
			etheriq(ether, pd->mb);
			pd->mb = mb;
			pd->addr = PADDR(mb->data);
			coherence();
		}

		pd->control = 0;
		COMMAND(port, Stall, upUnStall);

		q++;
	}
	ctlr->uphead = pd;

	ctlr->upqueued += q;
	if(q > ctlr->upqmax)
		ctlr->upqmax = q;
}

static void
receive(Ether* ether)
{
	int len, port, rxerror, rxstatus;
	Ctlr *ctlr;
	Msgbuf *mb, *rmb;

	port = ether->port;
	ctlr = ether->ctlr;

	while(((rxstatus = ins(port+RxStatus)) & rxIncomplete) == 0){
		if(ctlr->busmaster == 1 && (STATUS(port) & busMasterInProgress))
			break;

		/*
		 * If there was an error, log it and continue.
		 * Unfortunately the 3C5[078]9 has the error info in the status
		 * register and the 3C59[0257] implement a separate RxError
		 * register.
		 */
		if(rxstatus & rxError){
			if(ctlr->rxstatus9){
				switch(rxstatus & rxError9){

				case rxOverrun9:
				case oversizedFrame9:
				case runtFrame9:
				case alignmentError9:
					ether->ifc.rcverr++;
					break;
				case crcError9:
					ether->ifc.sumerr++;
					break;

				}
			}
			else{
				rxerror = inb(port+RxError);
				if(rxerror & (alignmentError|oversizedFrame|runtFrame|rxOverrun))
					ether->ifc.rcverr++;
				if(rxerror & crcError)
					ether->ifc.sumerr++;
			}
		}

		/*
		 * If there was an error or a new receive buffer can't be
		 * allocated, discard the packet and go on to the next.
		 */
		rmb = ctlr->rmb;
		if((rxstatus & rxError) || (mb = allocrmb()) == nil){
			COMMAND(port, RxDiscard, 0);
			while(STATUS(port) & commandInProgress)
				;

			if(ctlr->busmaster == 1)
				startdma(ether, PADDR(rmb->data));

			continue;
		}

		/*
		 * A valid receive packet awaits:
		 *	if using PIO, read it into the buffer;
		 *	discard the packet from the FIFO;
		 *	if using busmastering, start a new transfer for
		 *	  the next packet and as a side-effect get the
		 *	  end-pointer of the one just received;
		 *	pass the packet on to whoever wants it.
		 */
		if(ctlr->busmaster == 0 || ctlr->busmaster == 2){
			len = (rxstatus & rxBytes9);
			rmb->count = len;
			insl(port+Fifo, rmb->data, HOWMANY(len, 4));
		}

		COMMAND(port, RxDiscard, 0);
		while(STATUS(port) & commandInProgress)
			;

		if(ctlr->busmaster == 1)
			rmb->count = startdma(ether, PADDR(mb->data))-rmb->data;

		etheriq(ether, rmb);
		ctlr->rmb = mb;
	}
}

static void
interrupt(Ureg*, void* arg)
{
	Ether *ether;
	int port, status, s, txstatus, w, x;
	Ctlr *ctlr;

	ether = arg;
	port = ether->port;
	ctlr = ether->ctlr;

	ilock(&ctlr->wlock);
	status = STATUS(port);
	if(!(status & (interruptMask|interruptLatch))){
		iunlock(&ctlr->wlock);
		return;
	}
	w = (status>>13) & 0x07;
	COMMAND(port, SelectRegisterWindow, Wop);

	ctlr->interrupts++;
	if(ctlr->busmaster == 2)
		ctlr->timer[0] += inb(port+Timer905) & 0xFF;
	else
		ctlr->timer[0] += inb(port+Timer) & 0xFF;

	do{
		if(status & hostError){
			/*
			 * Adapter failure, try to find out why, reset if
			 * necessary. What happens if Tx is active and a reset
			 * occurs, need to retransmit? This probably isn't right.
			 */
			COMMAND(port, SelectRegisterWindow, Wdiagnostic);
			x = ins(port+FifoDiagnostic);
			COMMAND(port, SelectRegisterWindow, Wop);
			print("#l%d: status 0x%ux, diag 0x%ux\n",
			    ether->ctlrno, status, x);

			if(x & txOverrun){
				if(ctlr->busmaster == 0)
					COMMAND(port, TxReset, 0);
				else
					COMMAND(port, TxReset, (updnReset|dmaReset));
				COMMAND(port, TxEnable, 0);
			}

			if(x & rxUnderrun){
				/*
				 * This shouldn't happen...
				 * Reset the receiver and restore the filter and RxEarly
				 * threshold before re-enabling.
				 * Need to restart any busmastering?
				 */
				COMMAND(port, SelectRegisterWindow, Wstate);
				s = (port+RxFilter) & 0x000F;
				COMMAND(port, SelectRegisterWindow, Wop);
				COMMAND(port, RxReset, 0);
				while(STATUS(port) & commandInProgress)
					;
				COMMAND(port, SetRxFilter, s);
				COMMAND(port, SetRxEarlyThresh, ctlr->rxearly>>ctlr->ts);
				COMMAND(port, RxEnable, 0);
			}

			status &= ~hostError;
		}

		if(status & (transferInt|rxComplete)){
			receive(ether);
			status &= ~(transferInt|rxComplete);
		}

		if(status & (upComplete)){
			COMMAND(port, AcknowledgeInterrupt, upComplete);
			receive905(ether);
			status &= ~upComplete;
			ctlr->upinterrupts++;
		}

		if(status & txComplete){
			/*
			 * Pop the TxStatus stack, accumulating errors.
			 * Adjust the TX start threshold if there was an underrun.
			 * If there was a Jabber or Underrun error, reset
			 * the transmitter, taking care not to reset the dma logic
			 * as a busmaster receive may be in progress.
			 * For all conditions enable the transmitter.
			 */
			if(ctlr->busmaster == 2)
				txstatus = port+TxStatus905;
			else
				txstatus = port+TxStatus;
			s = 0;
			do{
				if(x = inb(txstatus))
					outb(txstatus, 0);
				s |= x;
			}while(STATUS(port) & txComplete);

			if(s & txUnderrun){
				if(ctlr->dnenabled){
					while(inl(port+PktStatus) & dnInProg)
						;
				}
				COMMAND(port, SelectRegisterWindow, Wdiagnostic);
				while(ins(port+MediaStatus) & txInProg)
					;
				COMMAND(port, SelectRegisterWindow, Wop);
				if(ctlr->txthreshold < ETHERMAXTU)
					ctlr->txthreshold += ETHERMINTU;
			}

			/*
			 * According to the manual, maxCollisions does not require
			 * a TxReset, merely a TxEnable. However, evidence points to
			 * it being necessary on the 3C905. The jury is still out.
			 * On busy or badly configured networks maxCollisions can
			 * happen frequently enough for messages to be annoying so
			 * keep quiet about them by popular request.
			 */
			if(s & (txJabber|txUnderrun|maxCollisions)){
				if(ctlr->busmaster == 0)
					COMMAND(port, TxReset, 0);
				else
					COMMAND(port, TxReset, (updnReset|dmaReset));
				while(STATUS(port) & commandInProgress)
					;
				COMMAND(port, SetTxStartThresh, ctlr->txthreshold>>ctlr->ts);
				if(ctlr->busmaster == 2)
					outl(port+TxFreeThresh, HOWMANY(ETHERMAXTU, 256));
				if(ctlr->dnenabled)
					status |= dnComplete;
			}

			if(s & ~(txStatusComplete|maxCollisions))
				print("#l%d: txstatus 0x%ux, threshold %d\n",
			    		ether->ctlrno, s, ctlr->txthreshold);
			COMMAND(port, TxEnable, 0);
			ether->ifc.txerr++;
			status &= ~txComplete;
			status |= txAvailable;
		}

		if(status & txAvailable){
			COMMAND(port, AcknowledgeInterrupt, txAvailable);
			ctlr->txbusy = 0;
			txstart(ether);
			status &= ~txAvailable;
		}

		if(status & dnComplete){
			COMMAND(port, AcknowledgeInterrupt, dnComplete);
			txstart905(ether);
			status &= ~dnComplete;
			ctlr->dninterrupts++;
		}

		if(status & updateStats){
			statistics(ether);
			status &= ~updateStats;
		}

		/*
		 * Currently, this shouldn't happen.
		 */
		if(status & rxEarly){
			COMMAND(port, AcknowledgeInterrupt, rxEarly);
			status &= ~rxEarly;
		}

		/*
		 * Panic if there are any interrupts not dealt with.
		 */
		if(status & interruptMask)
			panic("#l%d: interrupt mask 0x%ux\n", ether->ctlrno, status);

		COMMAND(port, AcknowledgeInterrupt, interruptLatch);
	}while((status = STATUS(port)) & (interruptMask|interruptLatch));

	if(ctlr->busmaster == 2)
		ctlr->timer[1] += inb(port+Timer905) & 0xFF;
	else
		ctlr->timer[1] += inb(port+Timer) & 0xFF;

	COMMAND(port, SelectRegisterWindow, w);
	iunlock(&ctlr->wlock);
}

static void
txrxreset(int port)
{
	COMMAND(port, TxReset, 0);
	while(STATUS(port) & commandInProgress)
		;
	COMMAND(port, RxReset, 0);
	while(STATUS(port) & commandInProgress)
		;
}

static void
tcmadapter(int port, int irq, int tbdf)
{
	Ctlr *ctlr;

	ctlr = ialloc(sizeof(Ctlr), 0);
	ctlr->port = port;
	ctlr->irq = irq;
	ctlr->tbdf = tbdf;

	if(ctlrhead != nil)
		ctlrtail->next = ctlr;
	else
		ctlrhead = ctlr;
	ctlrtail = ctlr;
}

/*
 * Write two 0 bytes to identify the IDport and then reset the
 * ID sequence. Then send the ID sequence to the card to get
 * the card into command state.
 */
static void
idseq(void)
{
	int i;
	uchar al;
	static int reset, untag;

	/*
	 * One time only:
	 *	reset any adapters listening
	 */
	if(reset == 0){
		outb(IDport, 0);
		outb(IDport, 0);
		outb(IDport, 0xC0);
		delay(20);
		reset = 1;
	}

	outb(IDport, 0);
	outb(IDport, 0);
	for(al = 0xFF, i = 0; i < 255; i++){
		outb(IDport, al);
		if(al & 0x80){
			al <<= 1;
			al ^= 0xCF;
		}
		else
			al <<= 1;
	}

	/*
	 * One time only:
	 *	write ID sequence to get the attention of all adapters;
	 *	untag all adapters.
	 * If a global reset is done here on all adapters it will confuse
	 * any ISA cards configured for EISA mode.
	 */
	if(untag == 0){
		outb(IDport, 0xD0);
		untag = 1;
	}
}

static ulong
activate(void)
{
	int i;
	ushort x, acr;

	/*
	 * Do the little configuration dance:
	 *
	 * 2. write the ID sequence to get to command state.
	 */
	idseq();

	/*
	 * 3. Read the Manufacturer ID from the EEPROM.
	 *    This is done by writing the IDPort with 0x87 (0x80
	 *    is the 'read EEPROM' command, 0x07 is the offset of
	 *    the Manufacturer ID field in the EEPROM).
	 *    The data comes back 1 bit at a time.
	 *    A delay seems necessary between reading the bits.
	 *
	 * If the ID doesn't match, there are no more adapters.
	 */
	outb(IDport, 0x87);
	delay(20);
	for(x = 0, i = 0; i < 16; i++){
		delay(20);
		x <<= 1;
		x |= inb(IDport) & 0x01;
	}
	if(x != 0x6D50)
		return 0;

	/*
	 * 3. Read the Address Configuration from the EEPROM.
	 *    The Address Configuration field is at offset 0x08 in the EEPROM).
	 */
	outb(IDport, 0x88);
	for(acr = 0, i = 0; i < 16; i++){
		delay(20);
		acr <<= 1;
		acr |= inb(IDport) & 0x01;
	}

	return (acr & 0x1F)*0x10 + 0x200;
}

static void
tcm509isa(void)
{
	int irq, port;

	/*
	 * Attempt to activate all adapters. If adapter is set for
	 * EISA mode (0x3F0), tag it and ignore. Otherwise, activate
	 * it fully.
	 */
	while(port = activate()){
		/*
		 * 6. Tag the adapter so it won't respond in future.
		 */
		outb(IDport, 0xD1);
		if(port == 0x3F0)
			continue;

		/*
		 * 6. Activate the adapter by writing the Activate command