/* $Id: hysdn_net.c,v 1.8.6.4 2001/09/23 22:24:54 kai Exp $ * * Linux driver for HYSDN cards, net (ethernet type) handling routines. * * Author Werner Cornelius (werner@titro.de) for Hypercope GmbH * Copyright 1999 by Werner Cornelius (werner@titro.de) * * This software may be used and distributed according to the terms * of the GNU General Public License, incorporated herein by reference. * * This net module has been inspired by the skeleton driver from * Donald Becker (becker@CESDIS.gsfc.nasa.gov) * */ #include #include #include #include #include #include #include #include "hysdn_defs.h" unsigned int hynet_enable = 0xffffffff; module_param(hynet_enable, uint, 0); #define MAX_SKB_BUFFERS 20 /* number of buffers for keeping TX-data */ /****************************************************************************/ /* structure containing the complete network data. The structure is aligned */ /* in a way that both, the device and statistics are kept inside it. */ /* for proper access, the device structure MUST be the first var/struct */ /* inside the definition. */ /****************************************************************************/ struct net_local { /* Tx control lock. This protects the transmit buffer ring * state along with the "tx full" state of the driver. This * means all netif_queue flow control actions are protected * by this lock as well. */ struct net_device *dev; spinlock_t lock; struct sk_buff *skbs[MAX_SKB_BUFFERS]; /* pointers to tx-skbs */ int in_idx, out_idx; /* indexes to buffer ring */ int sk_count; /* number of buffers currently in ring */ }; /* net_local */ /*********************************************************************/ /* Open/initialize the board. This is called (in the current kernel) */ /* sometime after booting when the 'ifconfig' program is run. */ /* This routine should set everything up anew at each open, even */ /* registers that "should" only need to be set once at boot, so that */ /* there is non-reboot way to recover if something goes wrong. */ /*********************************************************************/ static int net_open(struct net_device *dev) { struct in_device *in_dev; hysdn_card *card = dev->ml_priv; int i; netif_start_queue(dev); /* start tx-queueing */ /* Fill in the MAC-level header (if not already set) */ if (!card->mac_addr[0]) { for (i = 0; i < ETH_ALEN; i++) dev->dev_addr[i] = 0xfc; if ((in_dev = dev->ip_ptr) != NULL) { struct in_ifaddr *ifa = in_dev->ifa_list; if (ifa != NULL) memcpy(dev->dev_addr + (ETH_ALEN - sizeof(ifa->ifa_local)), &ifa->ifa_local, sizeof(ifa->ifa_local)); } } else memcpy(dev->dev_addr, card->mac_addr, ETH_ALEN); return (0); } /* net_open */ /*******************************************/ /* flush the currently occupied tx-buffers */ /* must only be called when device closed */ /*******************************************/ static void flush_tx_buffers(struct net_local *nl) { while (nl->sk_count) { dev_kfree_skb(nl->skbs[nl->out_idx++]); /* free skb */ if (nl->out_idx >= MAX_SKB_BUFFERS) nl->out_idx = 0; /* wrap around */ nl->sk_count--; } } /* flush_tx_buffers */ /*********************************************************************/ /* close/decativate the device. The device is not removed, but only */ /* deactivated. */ /*********************************************************************/ static int net_close(struct net_device *dev) { netif_stop_queue(dev); /* disable queueing */ flush_tx_buffers((struct net_local *) dev); return (0); /* success */ } /* net_close */ /************************************/ /* send a packet on this interface. */ /* new style for kernel >= 2.3.33 */ /************************************/ static netdev_tx_t net_send_packet(struct sk_buff *skb, struct net_device *dev) { struct net_local *lp = (struct net_local *) dev; spin_lock_irq(&lp->lock); lp->skbs[lp->in_idx++] = skb; /* add to buffer list */ if (lp->in_idx >= MAX_SKB_BUFFERS) lp->in_idx = 0; /* wrap around */ lp->sk_count++; /* adjust counter */ netif_trans_update(dev); /* If we just used up the very last entry in the * TX ring on this device, tell the queueing * layer to send no more. */ if (lp->sk_count >= MAX_SKB_BUFFERS) netif_stop_queue(dev); /* When the TX completion hw interrupt arrives, this * is when the transmit statistics are updated. */ spin_unlock_irq(&lp->lock); if (lp->sk_count <= 3) { schedule_work(&((hysdn_card *) dev->ml_priv)->irq_queue); } return NETDEV_TX_OK; /* success */ } /* net_send_packet */ /***********************************************************************/ /* acknowlegde a packet send. The network layer will be informed about */ /* completion */ /***********************************************************************/ void hysdn_tx_netack(hysdn_card *card) { struct net_local *lp = card->netif; if (!lp) return; /* non existing device */ if (!lp->sk_count) return; /* error condition */ lp->dev->stats.tx_packets++; lp->dev->stats.tx_bytes += lp->skbs[lp->out_idx]->len; dev_kfree_skb(lp->skbs[lp->out_idx++]); /* free skb */ if (lp->out_idx >= MAX_SKB_BUFFERS) lp->out_idx = 0; /* wrap around */ if (lp->sk_count-- == MAX_SKB_BUFFERS) /* dec usage count */ netif_start_queue((struct net_device *) lp); } /* hysdn_tx_netack */ /*****************************************************/ /* we got a packet from the network, go and queue it */ /*****************************************************/ void hysdn_rx_netpkt(hysdn_card *card, unsigned char *buf, unsigned short len) { struct net_local *lp = card->netif; struct net_device *dev; struct sk_buff *skb; if (!lp) return; /* non existing device */ dev = lp->dev; dev->stats.rx_bytes += len; skb = dev_alloc_skb(len); if (skb == NULL) { printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n", dev->name); dev->stats.rx_dropped++; return; } /* copy the data */ skb_put_data(skb, buf, len); /* determine the used protocol */ skb->protocol = eth_type_trans(skb, dev); dev->stats.rx_packets++; /* adjust packet count */ netif_rx(skb); } /* hysdn_rx_netpkt */ /*****************************************************/ /* return the pointer to a network packet to be send */ /*****************************************************/ struct sk_buff * hysdn_tx_netget(hysdn_card *card) { struct net_local *lp = card->netif; if (!lp) return (NULL); /* non existing device */ if (!lp->sk_count) return (NULL); /* nothing available */ return (lp->skbs[lp->out_idx]); /* next packet to send */ } /* hysdn_tx_netget */ static const struct net_device_ops hysdn_netdev_ops = { .ndo_open = net_open, .ndo_stop = net_close, .ndo_start_xmit = net_send_packet, .ndo_set_mac_address = eth_mac_addr, .ndo_validate_addr = eth_validate_addr, }; /*****************************************************************************/ /* hysdn_net_create creates a new net device for the given card. If a device */ /* already exists, it will be deleted and created a new one. The return value */ /* 0 announces success, else a negative error code will be returned. */ /*****************************************************************************/ int hysdn_net_create(hysdn_card *card) { struct net_device *dev; int i; struct net_local *lp; if (!card) { printk(KERN_WARNING "No card-pt in hysdn_net_create!\n"); return (-ENOMEM); } hysdn_net_release(card); /* release an existing net device */ dev = alloc_etherdev(sizeof(struct net_local)); if (!dev) { printk(KERN_WARNING "HYSDN: unable to allocate mem\n"); return (-ENOMEM); } lp = netdev_priv(dev); lp->dev = dev; dev->netdev_ops = &hysdn_netdev_ops; spin_lock_init(&((struct net_local *) dev)->lock); /* initialise necessary or informing fields */ dev->base_addr = card->iobase; /* IO address */ dev->irq = card->irq; /* irq */ dev->netdev_ops = &hysdn_netdev_ops; if ((i = register_netdev(dev))) { printk(KERN_WARNING "HYSDN: unable to create network device\n"); free_netdev(dev); return (i); } dev->ml_priv = card; /* remember pointer to own data structure */ card->netif = dev; /* setup the local pointer */ if (card->debug_flags & LOG_NET_INIT) hysdn_addlog(card, "network device created"); return (0); /* and return success */ } /* hysdn_net_create */ /***************************************************************************/ /* hysdn_net_release deletes the net device for the given card. The return */ /* value 0 announces success, else a negative error code will be returned. */ /***************************************************************************/ int hysdn_net_release(hysdn_card *card) { struct net_device *dev = card->netif; if (!dev) return (0); /* non existing */ card->netif = NULL; /* clear out pointer */ net_close(dev); flush_tx_buffers((struct net_local *) dev); /* empty buffers */ unregister_netdev(dev); /* release the device */ free_netdev(dev); /* release the memory allocated */ if (card->debug_flags & LOG_NET_INIT) hysdn_addlog(card, "network device deleted"); return (0); /* always successful */ } /* hysdn_net_release */ /*****************************************************************************/ /* hysdn_net_getname returns a pointer to the name of the network interface. */ /* if the interface is not existing, a "-" is returned. */ /*****************************************************************************/ char * hysdn_net_getname(hysdn_card *card) { struct net_device *dev = card->netif; if (!dev) return ("-"); /* non existing */ return (dev->name); } /* hysdn_net_getname */