aboutsummaryrefslogtreecommitdiff
path: root/arch/ia64/hp/sim/simeth.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/ia64/hp/sim/simeth.c')
-rw-r--r--arch/ia64/hp/sim/simeth.c530
1 files changed, 530 insertions, 0 deletions
diff --git a/arch/ia64/hp/sim/simeth.c b/arch/ia64/hp/sim/simeth.c
new file mode 100644
index 000000000000..ae84a1018a89
--- /dev/null
+++ b/arch/ia64/hp/sim/simeth.c
@@ -0,0 +1,530 @@
+/*
+ * Simulated Ethernet Driver
+ *
+ * Copyright (C) 1999-2001, 2003 Hewlett-Packard Co
+ * Stephane Eranian <eranian@hpl.hp.com>
+ */
+#include <linux/config.h>
+#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/system.h>
+#include <asm/irq.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 SSC_NETDEV_PROBE 100
+#define SSC_NETDEV_SEND 101
+#define SSC_NETDEV_RECV 102
+#define SSC_NETDEV_ATTACH 103
+#define SSC_NETDEV_DETACH 104
+
+#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, struct pt_regs * regs);
+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,
+ 0
+};
+
+
+/*
+ * 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;
+}
+
+extern long ia64_ssc (long, long, long, long, int);
+extern void ia64_ssc_connect_irq (long intr, long irq);
+
+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_connect(int irq)
+{
+ /* XXX Fix me
+ * this does not support multiple cards
+ * also no return value
+ */
+ ia64_ssc_connect_irq(NETWORK_INTR, irq);
+ return 0;
+}
+
+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);
+}
+
+/*
+ * 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, i, err;
+
+ /*
+ * 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 = dev->priv;
+ local->simfd = fd; /* keep track of underlying file descriptor */
+
+ dev->open = simeth_open;
+ dev->stop = simeth_close;
+ dev->hard_start_xmit = simeth_tx;
+ dev->get_stats = simeth_get_stats;
+ dev->set_multicast_list = set_multicast_list; /* no yet used */
+
+ err = register_netdev(dev);
+ if (err) {
+ free_netdev(dev);
+ return err;
+ }
+
+ dev->irq = assign_irq_vector(AUTO_ASSIGN);
+
+ /*
+ * attach the interrupt in the simulator, this does enable interrupts
+ * until a netdev_attach() is called
+ */
+ netdev_connect(dev->irq);
+
+ printk(KERN_INFO "%s: hosteth=%s simfd=%d, HwAddr",
+ dev->name, simeth_device, local->simfd);
+ for(i = 0; i < ETH_ALEN; i++) {
+ printk(" %2.2x", dev->dev_addr[i]);
+ }
+ printk(", IRQ %d\n", 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 = 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 ( 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, htonl(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 = dev->priv;
+ /* now do it for real */
+ r = event == NETDEV_UP ?
+ netdev_attach(local->simfd, dev->irq, htonl(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 = dev->priv;
+
+#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 0;
+}
+
+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;
+ }
+ nskb->dev = dev;
+
+ 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 = dev->priv;
+ /*
+ * 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
+ */
+ memcpy(skb->data, 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 pt_regs * regs)
+{
+ struct net_device *dev = dev_id;
+
+ if ( dev == NULL ) {
+ printk(KERN_WARNING "simeth: irq %d for unknown device\n", irq);
+ return IRQ_NONE;
+ }
+
+ /*
+ * 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 = dev->priv;
+
+ 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);