diff options
Diffstat (limited to 'kernel/arch/ia64/hp/sim/simeth.c')
| -rw-r--r-- | kernel/arch/ia64/hp/sim/simeth.c | 509 |
1 files changed, 509 insertions, 0 deletions
diff --git a/kernel/arch/ia64/hp/sim/simeth.c b/kernel/arch/ia64/hp/sim/simeth.c new file mode 100644 index 000000000..d1b04c4c9 --- /dev/null +++ b/kernel/arch/ia64/hp/sim/simeth.c @@ -0,0 +1,509 @@ +/* + * Simulated Ethernet Driver + * + * Copyright (C) 1999-2001, 2003 Hewlett-Packard Co + * Stephane Eranian <eranian@hpl.hp.com> + */ +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/types.h> +#include <linux/in.h> +#include <linux/string.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/inetdevice.h> +#include <linux/if_ether.h> +#include <linux/if_arp.h> +#include <linux/skbuff.h> +#include <linux/notifier.h> +#include <linux/bitops.h> +#include <asm/irq.h> +#include <asm/hpsim.h> + +#include "hpsim_ssc.h" + +#define SIMETH_RECV_MAX 10 + +/* + * Maximum possible received frame for Ethernet. + * We preallocate an sk_buff of that size to avoid costly + * memcpy for temporary buffer into sk_buff. We do basically + * what's done in other drivers, like eepro with a ring. + * The difference is, of course, that we don't have real DMA !!! + */ +#define SIMETH_FRAME_SIZE ETH_FRAME_LEN + + +#define NETWORK_INTR 8 + +struct simeth_local { + struct net_device_stats stats; + int simfd; /* descriptor in the simulator */ +}; + +static int simeth_probe1(void); +static int simeth_open(struct net_device *dev); +static int simeth_close(struct net_device *dev); +static int simeth_tx(struct sk_buff *skb, struct net_device *dev); +static int simeth_rx(struct net_device *dev); +static struct net_device_stats *simeth_get_stats(struct net_device *dev); +static irqreturn_t simeth_interrupt(int irq, void *dev_id); +static void set_multicast_list(struct net_device *dev); +static int simeth_device_event(struct notifier_block *this,unsigned long event, void *ptr); + +static char *simeth_version="0.3"; + +/* + * This variable is used to establish a mapping between the Linux/ia64 kernel + * and the host linux kernel. + * + * As of today, we support only one card, even though most of the code + * is ready for many more. The mapping is then: + * linux/ia64 -> linux/x86 + * eth0 -> eth1 + * + * In the future, we some string operations, we could easily support up + * to 10 cards (0-9). + * + * The default mapping can be changed on the kernel command line by + * specifying simeth=ethX (or whatever string you want). + */ +static char *simeth_device="eth0"; /* default host interface to use */ + + + +static volatile unsigned int card_count; /* how many cards "found" so far */ +static int simeth_debug; /* set to 1 to get debug information */ + +/* + * Used to catch IFF_UP & IFF_DOWN events + */ +static struct notifier_block simeth_dev_notifier = { + simeth_device_event, + NULL +}; + + +/* + * Function used when using a kernel command line option. + * + * Format: simeth=interface_name (like eth0) + */ +static int __init +simeth_setup(char *str) +{ + simeth_device = str; + return 1; +} + +__setup("simeth=", simeth_setup); + +/* + * Function used to probe for simeth devices when not installed + * as a loadable module + */ + +int __init +simeth_probe (void) +{ + int r; + + printk(KERN_INFO "simeth: v%s\n", simeth_version); + + r = simeth_probe1(); + + if (r == 0) register_netdevice_notifier(&simeth_dev_notifier); + + return r; +} + +static inline int +netdev_probe(char *name, unsigned char *ether) +{ + return ia64_ssc(__pa(name), __pa(ether), 0,0, SSC_NETDEV_PROBE); +} + + +static inline int +netdev_attach(int fd, int irq, unsigned int ipaddr) +{ + /* this puts the host interface in the right mode (start interrupting) */ + return ia64_ssc(fd, ipaddr, 0,0, SSC_NETDEV_ATTACH); +} + + +static inline int +netdev_detach(int fd) +{ + /* + * inactivate the host interface (don't interrupt anymore) */ + return ia64_ssc(fd, 0,0,0, SSC_NETDEV_DETACH); +} + +static inline int +netdev_send(int fd, unsigned char *buf, unsigned int len) +{ + return ia64_ssc(fd, __pa(buf), len, 0, SSC_NETDEV_SEND); +} + +static inline int +netdev_read(int fd, unsigned char *buf, unsigned int len) +{ + return ia64_ssc(fd, __pa(buf), len, 0, SSC_NETDEV_RECV); +} + +static const struct net_device_ops simeth_netdev_ops = { + .ndo_open = simeth_open, + .ndo_stop = simeth_close, + .ndo_start_xmit = simeth_tx, + .ndo_get_stats = simeth_get_stats, + .ndo_set_rx_mode = set_multicast_list, /* not yet used */ + +}; + +/* + * Function shared with module code, so cannot be in init section + * + * So far this function "detects" only one card (test_&_set) but could + * be extended easily. + * + * Return: + * - -ENODEV is no device found + * - -ENOMEM is no more memory + * - 0 otherwise + */ +static int +simeth_probe1(void) +{ + unsigned char mac_addr[ETH_ALEN]; + struct simeth_local *local; + struct net_device *dev; + int fd, err, rc; + + /* + * XXX Fix me + * let's support just one card for now + */ + if (test_and_set_bit(0, &card_count)) + return -ENODEV; + + /* + * check with the simulator for the device + */ + fd = netdev_probe(simeth_device, mac_addr); + if (fd == -1) + return -ENODEV; + + dev = alloc_etherdev(sizeof(struct simeth_local)); + if (!dev) + return -ENOMEM; + + memcpy(dev->dev_addr, mac_addr, sizeof(mac_addr)); + + local = netdev_priv(dev); + local->simfd = fd; /* keep track of underlying file descriptor */ + + dev->netdev_ops = &simeth_netdev_ops; + + err = register_netdev(dev); + if (err) { + free_netdev(dev); + return err; + } + + /* + * attach the interrupt in the simulator, this does enable interrupts + * until a netdev_attach() is called + */ + if ((rc = hpsim_get_irq(NETWORK_INTR)) < 0) + panic("%s: out of interrupt vectors!\n", __func__); + dev->irq = rc; + + printk(KERN_INFO "%s: hosteth=%s simfd=%d, HwAddr=%pm, IRQ %d\n", + dev->name, simeth_device, local->simfd, dev->dev_addr, dev->irq); + + return 0; +} + +/* + * actually binds the device to an interrupt vector + */ +static int +simeth_open(struct net_device *dev) +{ + if (request_irq(dev->irq, simeth_interrupt, 0, "simeth", dev)) { + printk(KERN_WARNING "simeth: unable to get IRQ %d.\n", dev->irq); + return -EAGAIN; + } + + netif_start_queue(dev); + + return 0; +} + +/* copied from lapbether.c */ +static __inline__ int dev_is_ethdev(struct net_device *dev) +{ + return ( dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5)); +} + + +/* + * Handler for IFF_UP or IFF_DOWN + * + * The reason for that is that we don't want to be interrupted when the + * interface is down. There is no way to unconnect in the simualtor. Instead + * we use this function to shutdown packet processing in the frame filter + * in the simulator. Thus no interrupts are generated + * + * + * That's also the place where we pass the IP address of this device to the + * simulator so that that we can start filtering packets for it + * + * There may be a better way of doing this, but I don't know which yet. + */ +static int +simeth_device_event(struct notifier_block *this,unsigned long event, void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct simeth_local *local; + struct in_device *in_dev; + struct in_ifaddr **ifap = NULL; + struct in_ifaddr *ifa = NULL; + int r; + + + if ( ! dev ) { + printk(KERN_WARNING "simeth_device_event dev=0\n"); + return NOTIFY_DONE; + } + + if (dev_net(dev) != &init_net) + return NOTIFY_DONE; + + if ( event != NETDEV_UP && event != NETDEV_DOWN ) return NOTIFY_DONE; + + /* + * Check whether or not it's for an ethernet device + * + * XXX Fixme: This works only as long as we support one + * type of ethernet device. + */ + if ( !dev_is_ethdev(dev) ) return NOTIFY_DONE; + + if ((in_dev=dev->ip_ptr) != NULL) { + for (ifap=&in_dev->ifa_list; (ifa=*ifap) != NULL; ifap=&ifa->ifa_next) + if (strcmp(dev->name, ifa->ifa_label) == 0) break; + } + if ( ifa == NULL ) { + printk(KERN_ERR "simeth_open: can't find device %s's ifa\n", dev->name); + return NOTIFY_DONE; + } + + printk(KERN_INFO "simeth_device_event: %s ipaddr=0x%x\n", + dev->name, ntohl(ifa->ifa_local)); + + /* + * XXX Fix me + * if the device was up, and we're simply reconfiguring it, not sure + * we get DOWN then UP. + */ + + local = netdev_priv(dev); + /* now do it for real */ + r = event == NETDEV_UP ? + netdev_attach(local->simfd, dev->irq, ntohl(ifa->ifa_local)): + netdev_detach(local->simfd); + + printk(KERN_INFO "simeth: netdev_attach/detach: event=%s ->%d\n", + event == NETDEV_UP ? "attach":"detach", r); + + return NOTIFY_DONE; +} + +static int +simeth_close(struct net_device *dev) +{ + netif_stop_queue(dev); + + free_irq(dev->irq, dev); + + return 0; +} + +/* + * Only used for debug + */ +static void +frame_print(unsigned char *from, unsigned char *frame, int len) +{ + int i; + + printk("%s: (%d) %02x", from, len, frame[0] & 0xff); + for(i=1; i < 6; i++ ) { + printk(":%02x", frame[i] &0xff); + } + printk(" %2x", frame[6] &0xff); + for(i=7; i < 12; i++ ) { + printk(":%02x", frame[i] &0xff); + } + printk(" [%02x%02x]\n", frame[12], frame[13]); + + for(i=14; i < len; i++ ) { + printk("%02x ", frame[i] &0xff); + if ( (i%10)==0) printk("\n"); + } + printk("\n"); +} + + +/* + * Function used to transmit of frame, very last one on the path before + * going to the simulator. + */ +static int +simeth_tx(struct sk_buff *skb, struct net_device *dev) +{ + struct simeth_local *local = netdev_priv(dev); + +#if 0 + /* ensure we have at least ETH_ZLEN bytes (min frame size) */ + unsigned int length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN; + /* Where do the extra padding bytes comes from inthe skbuff ? */ +#else + /* the real driver in the host system is going to take care of that + * or maybe it's the NIC itself. + */ + unsigned int length = skb->len; +#endif + + local->stats.tx_bytes += skb->len; + local->stats.tx_packets++; + + + if (simeth_debug > 5) frame_print("simeth_tx", skb->data, length); + + netdev_send(local->simfd, skb->data, length); + + /* + * we are synchronous on write, so we don't simulate a + * trasnmit complete interrupt, thus we don't need to arm a tx + */ + + dev_kfree_skb(skb); + return NETDEV_TX_OK; +} + +static inline struct sk_buff * +make_new_skb(struct net_device *dev) +{ + struct sk_buff *nskb; + + /* + * The +2 is used to make sure that the IP header is nicely + * aligned (on 4byte boundary I assume 14+2=16) + */ + nskb = dev_alloc_skb(SIMETH_FRAME_SIZE + 2); + if ( nskb == NULL ) { + printk(KERN_NOTICE "%s: memory squeeze. dropping packet.\n", dev->name); + return NULL; + } + + skb_reserve(nskb, 2); /* Align IP on 16 byte boundaries */ + + skb_put(nskb,SIMETH_FRAME_SIZE); + + return nskb; +} + +/* + * called from interrupt handler to process a received frame + */ +static int +simeth_rx(struct net_device *dev) +{ + struct simeth_local *local; + struct sk_buff *skb; + int len; + int rcv_count = SIMETH_RECV_MAX; + + local = netdev_priv(dev); + /* + * the loop concept has been borrowed from other drivers + * looks to me like it's a throttling thing to avoid pushing to many + * packets at one time into the stack. Making sure we can process them + * upstream and make forward progress overall + */ + do { + if ( (skb=make_new_skb(dev)) == NULL ) { + printk(KERN_NOTICE "%s: memory squeeze. dropping packet.\n", dev->name); + local->stats.rx_dropped++; + return 0; + } + /* + * Read only one frame at a time + */ + len = netdev_read(local->simfd, skb->data, SIMETH_FRAME_SIZE); + if ( len == 0 ) { + if ( simeth_debug > 0 ) printk(KERN_WARNING "%s: count=%d netdev_read=0\n", + dev->name, SIMETH_RECV_MAX-rcv_count); + break; + } +#if 0 + /* + * XXX Fix me + * Should really do a csum+copy here + */ + skb_copy_to_linear_data(skb, frame, len); +#endif + skb->protocol = eth_type_trans(skb, dev); + + if ( simeth_debug > 6 ) frame_print("simeth_rx", skb->data, len); + + /* + * push the packet up & trigger software interrupt + */ + netif_rx(skb); + + local->stats.rx_packets++; + local->stats.rx_bytes += len; + + } while ( --rcv_count ); + + return len; /* 0 = nothing left to read, otherwise, we can try again */ +} + +/* + * Interrupt handler (Yes, we can do it too !!!) + */ +static irqreturn_t +simeth_interrupt(int irq, void *dev_id) +{ + struct net_device *dev = dev_id; + + /* + * very simple loop because we get interrupts only when receiving + */ + while (simeth_rx(dev)); + return IRQ_HANDLED; +} + +static struct net_device_stats * +simeth_get_stats(struct net_device *dev) +{ + struct simeth_local *local = netdev_priv(dev); + + return &local->stats; +} + +/* fake multicast ability */ +static void +set_multicast_list(struct net_device *dev) +{ + printk(KERN_WARNING "%s: set_multicast_list called\n", dev->name); +} + +__initcall(simeth_probe); |