Convert the transmitter to be a ring buffer, too.

[netwatch.git] / net / 3c90x.c

diff --git a/net/3c90x.c b/net/3c90x.c
index 936f2973513d72c7b8980d3e4cb9018b84d1f85f..6d4eea0f319e3be212cf42f9c7bc9eca67dd5cdf 100644 (file)
--- a/net/3c90x.c
+++ b/net/3c90x.c
@@ -249,10 +249,6 @@ static struct
     INF_3C90X;
 
 static struct nic nic;
     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))
 
 #define _outl(v,a) outl((a),(v))
 #define _outw(v,a) outw((a),(v))


@@ -445,66 +441,104 @@ static void a3c90x_reset(void)
     return;
     }
 
     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 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 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);
                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;
        len = 0;
        n = 0;

-       oldpbuf = p;
+       txpbufs[txprod] = p;

        for (; p; p = p->next)
        {
        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++;
        }
                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 */

        
        

-       /** 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) **/
 
 #if 0          
        /** successful completion (sans "interrupt Requested" bit) **/


@@ -540,83 +574,120 @@ static void _transmit(struct pbuf *p)
 #endif
 }
 
 #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 * _recv(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;
        
        struct pbuf *p;
        

-       if (!currecv)
-               _setup_recv(nic);
-       

        /* Nothing to do? */
        /* 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?
 }
 
 /*** a3c90x_disable: exported routine to disable the card.  What's this for?


@@ -785,12 +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);
 
     _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.
      **
     /** Read the media options register, print a message and set default
      ** xcvr.
      **


@@ -909,10 +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);
 
     /** 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
 
     /**
      ** set Indication and Interrupt flags , acknowledge any IRQ's