Convert receive to be a ring buffer.

diff --git a/net/3c90x.c b/net/3c90x.c
index 936f2973513d72c7b8980d3e4cb9018b84d1f85f..56863271376d2be6b2a7bf30984702571319b5da 100644 (file)
--- a/net/3c90x.c
+++ b/net/3c90x.c
@@ -250,9 +250,6 @@ static struct
 
 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))
@@ -462,8 +459,11 @@ static void _transmit(struct pbuf *p)
        
        if (oldpbuf)
        {
+               int i = 0;
                while (!(inw(INF_3C90X.IOAddr + regCommandIntStatus_w) & INT_TXCOMPLETE) && oneshot_running())
-                       ;
+                       i++;
+               if (i)
+                       outputf("3c90x: had to wait %d loops to tx", i);
                if (!(inw(INF_3C90X.IOAddr + regCommandIntStatus_w) & INT_TXCOMPLETE))
                {
                        outputf("3c90x: tx timeout? txstat %02x", inb(INF_3C90X.IOAddr + regTxStatus_b));
@@ -540,83 +540,120 @@ static void _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 4
+
+static rxdesc_t rxdescs[RECV_BUFS];
+static struct pbuf *pbufs[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) || !pbufs[rxprod])
        {
-               outputf("3c90x: out of memory for packet?");
-               currecv = p;
-               return;
+               int i;
+               struct pbuf *p;
+               
+               if (!pbufs[rxprod])
+                       pbufs[rxprod] = p = pbuf_alloc(PBUF_RAW, MAX_RECV_SIZE, PBUF_POOL);
+               else {
+                       outputf("WARNING: 3c90x has pbuf in slot %d", rxprod);
+                       p = pbufs[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 && pbufs[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;
        
-       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);
                
-               pbuf_free(p);           /* Bounce the old one before setting it up again. */
-               _setup_recv(nic);
-               return NULL;
+                       p = NULL;       
+                       pbuf_free(pbufs[rxcons]);               /* Bounce the old one before setting it up again. */
+               } else {
+                       p = pbufs[rxcons];
+                       pbuf_realloc(p, rxdescs[rxcons].status & 0x1FFF);       /* Resize the packet to how large it actually is. */
+               }
+               
+               pbufs[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?
@@ -785,12 +822,6 @@ 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.
      **
@@ -909,10 +940,12 @@ 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

diff --git a/net/etherboot-compat.h b/net/etherboot-compat.h
index 0b121a3a0ea0011feeed1b063e01494799c9c63c..2f0626f487c9d4a2b1c404f4a14745d0e9b66b73 100644 (file)
--- a/net/etherboot-compat.h
+++ b/net/etherboot-compat.h
@@ -19,7 +19,7 @@ struct nic {
        
        unsigned char hwaddr[6];
 
-       struct pbuf * (*recv) (struct nic *nic);
+       int (*recv) (struct nic *nic);
        void (*transmit) (struct pbuf *p);
 };
 

diff --git a/net/net.c b/net/net.c
index e7bb80ab50f50c61b0dd9a8ebe9a4d557bd8d14d..0b573214256e4c975af7a78a1c68d0f1dd538c6c 100644 (file)
--- a/net/net.c
+++ b/net/net.c
@@ -25,10 +25,33 @@ static struct netif _netif;
 
 extern struct pci_driver a3c90x_driver;
 
-void eth_poll()
+void eth_recv(struct nic *nic, struct pbuf *p)
 {
-       struct pbuf *p;
        struct eth_hdr *ethhdr;
+       
+       LINK_STATS_INC(link.recv);
+       
+       ethhdr = p->payload;
+       
+       switch (htons(ethhdr->type)) {
+       case ETHTYPE_IP:
+       case ETHTYPE_ARP:
+               if (_netif.input(p, &_netif) != ERR_OK)
+               {
+                       LWIP_DEBUGF(NETIF_DEBUG, ("netdev_input: IP input error\n"));
+                       pbuf_free(p);
+               }
+               break;
+               
+       default:
+               outputf("Unhandled packet type %04x input", ethhdr->type);
+               pbuf_free(p);
+               break;
+       }
+}
+
+void eth_poll()
+{
        static int ticks = 0;
        int i = 15;     /* Don't process more than 15 packets at a time; we don't want the host to get TOO badly slowed down... */
        
@@ -45,29 +68,12 @@ void eth_poll()
                tcp_tmr();
        ticks++;
 
-       while ((i--) && ((p = _nic->recv(_nic)) != NULL))
+       while (i > 0)
        {
-//             outputf("NIC: Packet: %d bytes", p->tot_len);
-                       
-               LINK_STATS_INC(link.recv);
-               
-               ethhdr = p->payload;
-               
-               switch (htons(ethhdr->type)) {
-               case ETHTYPE_IP:
-               case ETHTYPE_ARP:
-                       if (_netif.input(p, &_netif) != ERR_OK)
-                       {
-                               LWIP_DEBUGF(NETIF_DEBUG, ("netdev_input: IP input error\n"));
-                               pbuf_free(p);
-                       }
-                       break;
-                       
-               default:
-                       outputf("Unhandled packet type %04x input", ethhdr->type);
-                       pbuf_free(p);
+               int n = _nic->recv(_nic);
+               i -= n;
+               if (n == 0)
                        break;
-               }
        }
 }
 

diff --git a/net/net.h b/net/net.h
index 7b522f0f2d40b1e0a64f5fa3a671feb93aec4d74..ae82f472dd29fa4193bdc07c878209b706be1aa3 100644 (file)
--- a/net/net.h
+++ b/net/net.h
@@ -2,8 +2,10 @@
 #define _NET_H
 
 #include "etherboot-compat.h"
+#include <lwip/pbuf.h>
 
 extern void eth_init();
+extern void eth_recv(struct nic *nic, struct pbuf *p);
 extern void eth_poll();
 extern int eth_register(struct nic *nic);