From: Joshua Wise Date: Sat, 6 Dec 2008 15:50:53 +0000 (-0500) Subject: Convert receive to be a ring buffer. X-Git-Url: http://git.joshuawise.com/netwatch.git/commitdiff_plain/bec09bd18a879a22688c68febaff8c65da41f752?ds=sidebyside Convert receive to be a ring buffer. --- diff --git a/net/3c90x.c b/net/3c90x.c index 936f297..5686327 100644 --- 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> (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 0b121a3..2f0626f 100644 --- 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 e7bb80a..0b57321 100644 --- 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 7b522f0..ae82f47 100644 --- a/net/net.h +++ b/net/net.h @@ -2,8 +2,10 @@ #define _NET_H #include "etherboot-compat.h" +#include 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);