X-Git-Url: http://git.joshuawise.com/netwatch.git/blobdiff_plain/80c7c8bffb0bdf3bc667a00bccae4dfe877906d4..73d65ee64db897452946c14e2b911b4c1f106b26:/net/3c90x.c

diff --git a/net/3c90x.c b/net/3c90x.c
index 74035e0..6d4eea0 100644
--- a/net/3c90x.c
+++ b/net/3c90x.c
@@ -249,10 +249,6 @@ static struct
     INF_3C90X;
 
 static struct nic nic;
-static txdesc_t txdesc;
-static rxdesc_t rxdesc;
-static struct pbuf *currecv;
-
 
 #define _outl(v,a) outl((a),(v))
 #define _outw(v,a) outw((a),(v))
@@ -445,69 +441,104 @@ static void a3c90x_reset(void)
     return;
     }
 
+/***************************** Transmit routines *****************************/
 
+#define XMIT_BUFS 8
 
-/*** a3c90x_transmit: exported function that transmits a packet.  Does not
- *** return any particular status.  Parameters are:
- *** dest_addr[6] - destination address, ethernet;
- *** proto - protocol type (ARP, IP, etc);
- *** size - size of the non-header part of the packet that needs transmitted;
- *** pkt - the pointer to the packet data itself.
- ***/
-static void
-a3c90x_transmit(struct pbuf *p)
+static txdesc_t txdescs[XMIT_BUFS];
+static struct pbuf *txpbufs[XMIT_BUFS] = {0,};
+
+/* txcons is the index into the ring buffer of the last packet that the
+ * 3c90x was seen processing, or -1 if the 3c90x was idle.
+ */
+static int txcons = -1;
+
+/* txprod is the index of the _next_ buffer that the driver will write into. */
+static int txprod = 0;
+
+/* _transmit adds a packet to the transmit ring buffer.  If no space is
+ * available in the buffer, then _transmit blocks until a packet has been
+ * transmitted.
+ */
+static void _transmit(struct pbuf *p)
 {
 	unsigned char status;
-	static struct pbuf *oldpbuf = NULL;
-	unsigned int n, len;
+	int len, n;
 	
-	if (oldpbuf)
+	/* Wait for there to be space. */
+	if (txcons == txprod)
 	{
-		while (!(inw(INF_3C90X.IOAddr + regCommandIntStatus_w) & INT_TXCOMPLETE) && oneshot_running())
-			;
-		if (!(inw(INF_3C90X.IOAddr + regCommandIntStatus_w) & INT_TXCOMPLETE))
+		int i = 0;
+		
+		outputf("3c90x: txbuf full, waiting for space...");
+		while (inl(INF_3C90X.IOAddr + regDnListPtr_l) != 0)
+			i++;
+		outputf("3c90x: took %d iters", i);
+	}
+	
+	/* Stall the download engine so it doesn't bother us. */
+	_issue_command(INF_3C90X.IOAddr, cmdStallCtl, 2 /* Stall download */);
+	
+	/* Clean up old txcons. */
+	if (txcons != -1)
+	{
+		unsigned long curp = inl(INF_3C90X.IOAddr + regDnListPtr_l);
+		int end;
+		
+		if (curp == 0)
+			end = txprod;
+		else
+			end = (curp - v2p(txdescs)) / sizeof(txdescs[0]);
+		
+		while (txcons != end)
 		{
-			outputf("3c90x: tx timeout? txstat %02x", inb(INF_3C90X.IOAddr + regTxStatus_b));
-			outputf("3c90x: Gen sts %04x", inw(INF_3C90X.IOAddr + regCommandIntStatus_w));
+			pbuf_free(txpbufs[txcons]);
+			txpbufs[txcons] = NULL;
+			txdescs[txcons].hdr = 0;
+			txdescs[txcons].next = 0;
+			txcons = (txcons + 1) % XMIT_BUFS;
 		}
-		status = inb(INF_3C90X.IOAddr + regTxStatus_b);
+		if (txcons == txprod)
+			txcons = -1;
+	}
+	
+	/* Look at the TX status */
+	status = inb(INF_3C90X.IOAddr + regTxStatus_b);
+	if (status)
+	{
+		outputf("3c90x: error: the nus.");
 		outb(INF_3C90X.IOAddr + regTxStatus_b, 0x00);
-		pbuf_free(oldpbuf);
-		oldpbuf = NULL;
 	}
 
-	_issue_command(INF_3C90X.IOAddr, cmdStallCtl, 2 /* Stall download */);
-
-	/** Setup the DPD (download descriptor) **/
-	txdesc.next = 0;
+	/* Set up the new txdesc. */
+	txdescs[txprod].next = 0;
 	len = 0;
 	n = 0;
-	oldpbuf = p;
+	txpbufs[txprod] = p;
 	for (; p; p = p->next)
 	{
-		txdesc.segments[n].addr = v2p(p->payload);
-		txdesc.segments[n].len = p->len | (p->next ? 0 : (1 << 31));
+		txdescs[txprod].segments[n].addr = v2p(p->payload);
+		txdescs[txprod].segments[n].len = p->len | (p->next ? 0 : (1 << 31));
 		len += p->len;
 		pbuf_ref(p);
 		n++;
 	}
-	/** set notification for transmission completion (bit 15) **/
-	txdesc.hdr = (len) | 0x8000;
+	txdescs[txprod].hdr = len;	/* If we wanted completion notification, bit 15 */
 	
-	outputf("3c90x: Sending %d byte %d seg packet", len, n);
-
-	/** Send the packet **/
-	outl(INF_3C90X.IOAddr + regDnListPtr_l, v2p(&txdesc));
-	_issue_command(INF_3C90X.IOAddr, cmdStallCtl, 3 /* Unstall download */);
-		
-	oneshot_start_ms(10);
-	while((inl(INF_3C90X.IOAddr + regDnListPtr_l) != 0) && oneshot_running())
-		;
-	if (!oneshot_running())
+	/* Now link the new one in, after it's been set up. */
+	txdescs[(txprod + XMIT_BUFS - 1) % XMIT_BUFS].next = v2p(&(txdescs[txprod]));
+	
+	/* If the card is stopped, start it up again. */
+	if (inl(INF_3C90X.IOAddr + regDnListPtr_l) == 0)
 	{
-		outputf("3c90x: Download engine pointer timeout");
-		return;
+		outl(INF_3C90X.IOAddr + regDnListPtr_l, v2p(&(txdescs[txprod])));
+		txcons = txprod;
 	}
+	
+	txprod = (txprod + 1) % XMIT_BUFS;
+	
+	/* And let it proceed on its way. */
+	_issue_command(INF_3C90X.IOAddr, cmdStallCtl, 3 /* Unstall download */);
 
 #if 0		
 	/** successful completion (sans "interrupt Requested" bit) **/
@@ -543,83 +574,120 @@ a3c90x_transmit(struct pbuf *p)
 #endif
 }
 
-/* _setup_recv allocates and sets a pbuf from lwIP as the active receive
- * packet chain for the 3c90x.  The 3c90x must not be trying to receive
- * when _setup_recv is being called.
+/***************************** Receive routines *****************************/
+#define MAX_RECV_SIZE 1536
+#define RECV_BUFS 16
+
+static rxdesc_t rxdescs[RECV_BUFS];
+static struct pbuf *rxpbufs[RECV_BUFS] = {0,};
+
+/* rxcons is the pointer to the receive descriptor that the ethernet card will
+ * write into next.
+ */
+static int rxcons = 0;
+
+/* rxprod is the pointer to the receive descriptor that the driver will
+ * allocate next.
  */
-static void _setup_recv(struct nic *nic)
+static int rxprod = 0;
+
+/* _recv_prepare fills the 3c90x's ring buffer with fresh pbufs from lwIP.
+ * The upload engine need not be stalled.
+ */
+static void _recv_prepare(struct nic *nic)
 {
-	struct pbuf *p, *q;
-	int i;
-	
-	rxdesc.status = 0;	/* Clear it out in the very beginning. */
-	
-	p = pbuf_alloc(PBUF_RAW, 1536 /* XXX magic Max len */, PBUF_POOL);
-	if (!p)
+	int oldprod;
+
+	oldprod = rxprod;
+	while ((rxprod != rxcons) || !rxpbufs[rxprod])
 	{
-		outputf("3c90x: out of memory for packet?");
-		currecv = p;
-		return;
+		int i;
+		struct pbuf *p;
+		
+		if (!rxpbufs[rxprod])
+			rxpbufs[rxprod] = p = pbuf_alloc(PBUF_RAW, MAX_RECV_SIZE, PBUF_POOL);
+		else {
+			outputf("WARNING: 3c90x has pbuf in slot %d", rxprod);
+			p = rxpbufs[rxprod];
+		}
+		
+		if (!p)
+		{
+			outputf("3c90x: out of memory for rx pbuf?");
+			break;
+		}
+		
+		rxdescs[rxprod].status = 0;
+		rxdescs[rxprod].next = 0;
+		for (i = 0; p; p = p->next, i++)
+		{
+			rxdescs[rxprod].segments[i].addr = v2p(p->payload);
+			rxdescs[rxprod].segments[i].len = p->len | (p->next ? 0 : (1 << 31));
+		}
+		
+		/* Hook in the new one after and only after it's been fully set up. */
+		rxdescs[(rxprod + RECV_BUFS - 1) % RECV_BUFS].next = v2p(&(rxdescs[rxprod]));
+		rxprod = (rxprod + 1) % RECV_BUFS;
 	}
 	
-	rxdesc.next = 0;
-	rxdesc.status = 0;
-	for (i = 0, q = p; q; q = q->next, i++)
+	if (inl(INF_3C90X.IOAddr + regUpListPtr_l) == 0 && rxpbufs[oldprod])	/* Ran out of shit, and got new shit? */
 	{
-		rxdesc.segments[i].addr = v2p(q->payload);
-		rxdesc.segments[i].len = q->len | (q->next ? 0 : (1 << 31));
+		outl(INF_3C90X.IOAddr + regUpListPtr_l, v2p(&rxdescs[oldprod]));
+		outputf("3c90x: WARNING: Ran out of rx slots");
 	}
 	
-	outl(INF_3C90X.IOAddr + regUpListPtr_l, v2p(&rxdesc));
-	
-	currecv = p;
 }
 
-/*** a3c90x_poll: exported routine that waits for a certain length of time
- *** for a packet, and if it sees none, returns 0.  This routine should
- *** copy the packet to nic->packet if it gets a packet and set the size
- *** in nic->packetlen.  Return 1 if a packet was found.
- ***/
-static struct pbuf * a3c90x_poll(struct nic *nic)
+/* _recv polls the ring buffer to see if any packets are available.  If any 
+ * are, then eth_recv is called for each available.  _recv returns how many
+ * packets it received successfully.  Whether _recv got any packets or not,
+ * _recv does not block, and reinitializes the ring buffer with fresh pbufs.
+ */
+static int _recv(struct nic *nic)
 {
-	int errcode;
+	int errcode, n = 0;
 	struct pbuf *p;
 	
-	if (!currecv)
-		_setup_recv(nic);
-	
 	/* Nothing to do? */
-	if ((rxdesc.status & ((1<<14) | (1<<15))) == 0)
-		return NULL;
-	
-	p = currecv;
-	
-	/** Check for Error (else we have good packet) **/
-	if (rxdesc.status & (1<<14))
+	while ((rxdescs[rxcons].status & ((1<<14) | (1<<15))) != 0)
 	{
-		errcode = rxdesc.status;
-		if (errcode & (1<<16))
-			outputf("3C90X: Rx Overrun (%hX)",errcode>>16);
-		else if (errcode & (1<<17))
-			outputf("3C90X: Runt Frame (%hX)",errcode>>16);
-		else if (errcode & (1<<18))
-			outputf("3C90X: Alignment Error (%hX)",errcode>>16);
-		else if (errcode & (1<<19))
-			outputf("3C90X: CRC Error (%hX)",errcode>>16);
-		else if (errcode & (1<<20))
-			outputf("3C90X: Oversized Frame (%hX)",errcode>>16);
-		else
-			outputf("3C90X: Packet error (%hX)",errcode>>16);
+		/** Check for Error (else we have good packet) **/
+		if (rxdescs[rxcons].status & (1<<14))
+		{
+			errcode = rxdescs[rxcons].status;
+			if (errcode & (1<<16))
+				outputf("3C90X: Rx Overrun (%hX)",errcode>>16);
+			else if (errcode & (1<<17))
+				outputf("3C90X: Runt Frame (%hX)",errcode>>16);
+			else if (errcode & (1<<18))
+				outputf("3C90X: Alignment Error (%hX)",errcode>>16);
+			else if (errcode & (1<<19))
+				outputf("3C90X: CRC Error (%hX)",errcode>>16);
+			else if (errcode & (1<<20))
+				outputf("3C90X: Oversized Frame (%hX)",errcode>>16);
+			else
+				outputf("3C90X: Packet error (%hX)",errcode>>16);
+		
+			p = NULL;	
+			pbuf_free(rxpbufs[rxcons]);		/* Bounce the old one before setting it up again. */
+		} else {
+			p = rxpbufs[rxcons];
+			pbuf_realloc(p, rxdescs[rxcons].status & 0x1FFF);	/* Resize the packet to how large it actually is. */
+		}
 		
-		pbuf_free(p);		/* Bounce the old one before setting it up again. */
-		_setup_recv(nic);
-		return NULL;
+		rxpbufs[rxcons] = NULL;
+		rxdescs[rxcons].status = 0; 
+		rxcons = (rxcons + 1) % RECV_BUFS;
+		
+		if (p)
+		{
+			eth_recv(nic, p);
+			n++;
+		}
 	}
 
-	pbuf_realloc(p, rxdesc.status & 0x1FFF);	/* Resize the packet to how large it actually is. */
-	_setup_recv(nic);	/* ..and light the NIC up again. */
-	
-	return p;
+	_recv_prepare(nic);	/* Light the NIC up again. */
+	return n;
 }
 
 /*** a3c90x_disable: exported routine to disable the card.  What's this for?
@@ -788,12 +856,6 @@ static int a3c90x_probe(struct pci_dev * pci, void * data)
     _outw(0, INF_3C90X.IOAddr + regStationMask_2_3w+2);
     _outw(0, INF_3C90X.IOAddr + regStationMask_2_3w+4);
 
-    /** Fill in our entry in the etherboot arp table **/
-/* XXX ? for lwip? 
-    for(i=0;i<ETH_ALEN;i++)
-	nic.node_addr[i] = (eeprom[HWADDR_OFFSET + i/2] >> (8*((i&1)^1))) & 0xff;
-*/
-
     /** Read the media options register, print a message and set default
      ** xcvr.
      **
@@ -912,10 +974,12 @@ static int a3c90x_probe(struct pci_dev * pci, void * data)
 
     /** Set the RX filter = receive only individual pkts & multicast & bcast. **/
     _issue_command(INF_3C90X.IOAddr, cmdSetRxFilter, 0x01 + 0x02 + 0x04);
-    _issue_command(INF_3C90X.IOAddr, cmdRxEnable, 0);
     
-    /* Now stick a packet in the queue. */
-    _setup_recv(&nic);
+    /* Stick some packets in the queue. */
+    _recv_prepare(&nic);
+    
+    /* And light up the RX engine. */
+    _issue_command(INF_3C90X.IOAddr, cmdRxEnable, 0);
 
     /**
      ** set Indication and Interrupt flags , acknowledge any IRQ's
@@ -925,8 +989,8 @@ static int a3c90x_probe(struct pci_dev * pci, void * data)
     _issue_command(INF_3C90X.IOAddr, cmdAcknowledgeInterrupt, 0x661);
 
     /* * Set our exported functions **/
-    nic.recv     = a3c90x_poll;
-    nic.transmit = a3c90x_transmit;
+    nic.recv     = _recv;
+    nic.transmit = _transmit;
     memcpy(nic.hwaddr, INF_3C90X.HWAddr, 6);
     eth_register(&nic);