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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Simulated Ethernet Driver | |
3 | * | |
4 | * Copyright (C) 1999-2001, 2003 Hewlett-Packard Co | |
5 | * Stephane Eranian <eranian@hpl.hp.com> | |
6 | */ | |
1da177e4 LT |
7 | #include <linux/kernel.h> |
8 | #include <linux/sched.h> | |
9 | #include <linux/types.h> | |
10 | #include <linux/in.h> | |
11 | #include <linux/string.h> | |
12 | #include <linux/init.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/interrupt.h> | |
15 | #include <linux/netdevice.h> | |
16 | #include <linux/etherdevice.h> | |
17 | #include <linux/inetdevice.h> | |
18 | #include <linux/if_ether.h> | |
19 | #include <linux/if_arp.h> | |
20 | #include <linux/skbuff.h> | |
21 | #include <linux/notifier.h> | |
22 | #include <linux/bitops.h> | |
23 | #include <asm/system.h> | |
24 | #include <asm/irq.h> | |
25 | ||
26 | #define SIMETH_RECV_MAX 10 | |
27 | ||
28 | /* | |
29 | * Maximum possible received frame for Ethernet. | |
30 | * We preallocate an sk_buff of that size to avoid costly | |
31 | * memcpy for temporary buffer into sk_buff. We do basically | |
32 | * what's done in other drivers, like eepro with a ring. | |
33 | * The difference is, of course, that we don't have real DMA !!! | |
34 | */ | |
35 | #define SIMETH_FRAME_SIZE ETH_FRAME_LEN | |
36 | ||
37 | ||
38 | #define SSC_NETDEV_PROBE 100 | |
39 | #define SSC_NETDEV_SEND 101 | |
40 | #define SSC_NETDEV_RECV 102 | |
41 | #define SSC_NETDEV_ATTACH 103 | |
42 | #define SSC_NETDEV_DETACH 104 | |
43 | ||
44 | #define NETWORK_INTR 8 | |
45 | ||
46 | struct simeth_local { | |
47 | struct net_device_stats stats; | |
48 | int simfd; /* descriptor in the simulator */ | |
49 | }; | |
50 | ||
51 | static int simeth_probe1(void); | |
52 | static int simeth_open(struct net_device *dev); | |
53 | static int simeth_close(struct net_device *dev); | |
54 | static int simeth_tx(struct sk_buff *skb, struct net_device *dev); | |
55 | static int simeth_rx(struct net_device *dev); | |
56 | static struct net_device_stats *simeth_get_stats(struct net_device *dev); | |
57 | static irqreturn_t simeth_interrupt(int irq, void *dev_id, struct pt_regs * regs); | |
58 | static void set_multicast_list(struct net_device *dev); | |
59 | static int simeth_device_event(struct notifier_block *this,unsigned long event, void *ptr); | |
60 | ||
61 | static char *simeth_version="0.3"; | |
62 | ||
63 | /* | |
64 | * This variable is used to establish a mapping between the Linux/ia64 kernel | |
65 | * and the host linux kernel. | |
66 | * | |
67 | * As of today, we support only one card, even though most of the code | |
68 | * is ready for many more. The mapping is then: | |
69 | * linux/ia64 -> linux/x86 | |
70 | * eth0 -> eth1 | |
71 | * | |
72 | * In the future, we some string operations, we could easily support up | |
73 | * to 10 cards (0-9). | |
74 | * | |
75 | * The default mapping can be changed on the kernel command line by | |
76 | * specifying simeth=ethX (or whatever string you want). | |
77 | */ | |
78 | static char *simeth_device="eth0"; /* default host interface to use */ | |
79 | ||
80 | ||
81 | ||
82 | static volatile unsigned int card_count; /* how many cards "found" so far */ | |
83 | static int simeth_debug; /* set to 1 to get debug information */ | |
84 | ||
85 | /* | |
86 | * Used to catch IFF_UP & IFF_DOWN events | |
87 | */ | |
88 | static struct notifier_block simeth_dev_notifier = { | |
89 | simeth_device_event, | |
90 | 0 | |
91 | }; | |
92 | ||
93 | ||
94 | /* | |
95 | * Function used when using a kernel command line option. | |
96 | * | |
97 | * Format: simeth=interface_name (like eth0) | |
98 | */ | |
99 | static int __init | |
100 | simeth_setup(char *str) | |
101 | { | |
102 | simeth_device = str; | |
103 | return 1; | |
104 | } | |
105 | ||
106 | __setup("simeth=", simeth_setup); | |
107 | ||
108 | /* | |
109 | * Function used to probe for simeth devices when not installed | |
110 | * as a loadable module | |
111 | */ | |
112 | ||
113 | int __init | |
114 | simeth_probe (void) | |
115 | { | |
116 | int r; | |
117 | ||
118 | printk(KERN_INFO "simeth: v%s\n", simeth_version); | |
119 | ||
120 | r = simeth_probe1(); | |
121 | ||
122 | if (r == 0) register_netdevice_notifier(&simeth_dev_notifier); | |
123 | ||
124 | return r; | |
125 | } | |
126 | ||
127 | extern long ia64_ssc (long, long, long, long, int); | |
128 | extern void ia64_ssc_connect_irq (long intr, long irq); | |
129 | ||
130 | static inline int | |
131 | netdev_probe(char *name, unsigned char *ether) | |
132 | { | |
133 | return ia64_ssc(__pa(name), __pa(ether), 0,0, SSC_NETDEV_PROBE); | |
134 | } | |
135 | ||
136 | ||
137 | static inline int | |
138 | netdev_connect(int irq) | |
139 | { | |
140 | /* XXX Fix me | |
141 | * this does not support multiple cards | |
142 | * also no return value | |
143 | */ | |
144 | ia64_ssc_connect_irq(NETWORK_INTR, irq); | |
145 | return 0; | |
146 | } | |
147 | ||
148 | static inline int | |
149 | netdev_attach(int fd, int irq, unsigned int ipaddr) | |
150 | { | |
151 | /* this puts the host interface in the right mode (start interrupting) */ | |
152 | return ia64_ssc(fd, ipaddr, 0,0, SSC_NETDEV_ATTACH); | |
153 | } | |
154 | ||
155 | ||
156 | static inline int | |
157 | netdev_detach(int fd) | |
158 | { | |
159 | /* | |
160 | * inactivate the host interface (don't interrupt anymore) */ | |
161 | return ia64_ssc(fd, 0,0,0, SSC_NETDEV_DETACH); | |
162 | } | |
163 | ||
164 | static inline int | |
165 | netdev_send(int fd, unsigned char *buf, unsigned int len) | |
166 | { | |
167 | return ia64_ssc(fd, __pa(buf), len, 0, SSC_NETDEV_SEND); | |
168 | } | |
169 | ||
170 | static inline int | |
171 | netdev_read(int fd, unsigned char *buf, unsigned int len) | |
172 | { | |
173 | return ia64_ssc(fd, __pa(buf), len, 0, SSC_NETDEV_RECV); | |
174 | } | |
175 | ||
176 | /* | |
177 | * Function shared with module code, so cannot be in init section | |
178 | * | |
179 | * So far this function "detects" only one card (test_&_set) but could | |
180 | * be extended easily. | |
181 | * | |
182 | * Return: | |
183 | * - -ENODEV is no device found | |
184 | * - -ENOMEM is no more memory | |
185 | * - 0 otherwise | |
186 | */ | |
187 | static int | |
188 | simeth_probe1(void) | |
189 | { | |
190 | unsigned char mac_addr[ETH_ALEN]; | |
191 | struct simeth_local *local; | |
192 | struct net_device *dev; | |
3b5cc090 | 193 | int fd, i, err, rc; |
1da177e4 LT |
194 | |
195 | /* | |
196 | * XXX Fix me | |
197 | * let's support just one card for now | |
198 | */ | |
199 | if (test_and_set_bit(0, &card_count)) | |
200 | return -ENODEV; | |
201 | ||
202 | /* | |
203 | * check with the simulator for the device | |
204 | */ | |
205 | fd = netdev_probe(simeth_device, mac_addr); | |
206 | if (fd == -1) | |
207 | return -ENODEV; | |
208 | ||
209 | dev = alloc_etherdev(sizeof(struct simeth_local)); | |
210 | if (!dev) | |
211 | return -ENOMEM; | |
212 | ||
213 | memcpy(dev->dev_addr, mac_addr, sizeof(mac_addr)); | |
214 | ||
215 | local = dev->priv; | |
216 | local->simfd = fd; /* keep track of underlying file descriptor */ | |
217 | ||
218 | dev->open = simeth_open; | |
219 | dev->stop = simeth_close; | |
220 | dev->hard_start_xmit = simeth_tx; | |
221 | dev->get_stats = simeth_get_stats; | |
222 | dev->set_multicast_list = set_multicast_list; /* no yet used */ | |
223 | ||
224 | err = register_netdev(dev); | |
225 | if (err) { | |
226 | free_netdev(dev); | |
227 | return err; | |
228 | } | |
229 | ||
3b5cc090 KK |
230 | if ((rc = assign_irq_vector(AUTO_ASSIGN)) < 0) |
231 | panic("%s: out of interrupt vectors!\n", __FUNCTION__); | |
232 | dev->irq = rc; | |
1da177e4 LT |
233 | |
234 | /* | |
235 | * attach the interrupt in the simulator, this does enable interrupts | |
236 | * until a netdev_attach() is called | |
237 | */ | |
238 | netdev_connect(dev->irq); | |
239 | ||
240 | printk(KERN_INFO "%s: hosteth=%s simfd=%d, HwAddr", | |
241 | dev->name, simeth_device, local->simfd); | |
242 | for(i = 0; i < ETH_ALEN; i++) { | |
243 | printk(" %2.2x", dev->dev_addr[i]); | |
244 | } | |
245 | printk(", IRQ %d\n", dev->irq); | |
246 | ||
247 | return 0; | |
248 | } | |
249 | ||
250 | /* | |
251 | * actually binds the device to an interrupt vector | |
252 | */ | |
253 | static int | |
254 | simeth_open(struct net_device *dev) | |
255 | { | |
256 | if (request_irq(dev->irq, simeth_interrupt, 0, "simeth", dev)) { | |
257 | printk(KERN_WARNING "simeth: unable to get IRQ %d.\n", dev->irq); | |
258 | return -EAGAIN; | |
259 | } | |
260 | ||
261 | netif_start_queue(dev); | |
262 | ||
263 | return 0; | |
264 | } | |
265 | ||
266 | /* copied from lapbether.c */ | |
267 | static __inline__ int dev_is_ethdev(struct net_device *dev) | |
268 | { | |
269 | return ( dev->type == ARPHRD_ETHER && strncmp(dev->name, "dummy", 5)); | |
270 | } | |
271 | ||
272 | ||
273 | /* | |
274 | * Handler for IFF_UP or IFF_DOWN | |
275 | * | |
276 | * The reason for that is that we don't want to be interrupted when the | |
277 | * interface is down. There is no way to unconnect in the simualtor. Instead | |
278 | * we use this function to shutdown packet processing in the frame filter | |
279 | * in the simulator. Thus no interrupts are generated | |
280 | * | |
281 | * | |
282 | * That's also the place where we pass the IP address of this device to the | |
283 | * simulator so that that we can start filtering packets for it | |
284 | * | |
285 | * There may be a better way of doing this, but I don't know which yet. | |
286 | */ | |
287 | static int | |
288 | simeth_device_event(struct notifier_block *this,unsigned long event, void *ptr) | |
289 | { | |
290 | struct net_device *dev = ptr; | |
291 | struct simeth_local *local; | |
292 | struct in_device *in_dev; | |
293 | struct in_ifaddr **ifap = NULL; | |
294 | struct in_ifaddr *ifa = NULL; | |
295 | int r; | |
296 | ||
297 | ||
298 | if ( ! dev ) { | |
299 | printk(KERN_WARNING "simeth_device_event dev=0\n"); | |
300 | return NOTIFY_DONE; | |
301 | } | |
302 | ||
303 | if ( event != NETDEV_UP && event != NETDEV_DOWN ) return NOTIFY_DONE; | |
304 | ||
305 | /* | |
306 | * Check whether or not it's for an ethernet device | |
307 | * | |
308 | * XXX Fixme: This works only as long as we support one | |
309 | * type of ethernet device. | |
310 | */ | |
311 | if ( !dev_is_ethdev(dev) ) return NOTIFY_DONE; | |
312 | ||
313 | if ((in_dev=dev->ip_ptr) != NULL) { | |
314 | for (ifap=&in_dev->ifa_list; (ifa=*ifap) != NULL; ifap=&ifa->ifa_next) | |
315 | if (strcmp(dev->name, ifa->ifa_label) == 0) break; | |
316 | } | |
317 | if ( ifa == NULL ) { | |
318 | printk(KERN_ERR "simeth_open: can't find device %s's ifa\n", dev->name); | |
319 | return NOTIFY_DONE; | |
320 | } | |
321 | ||
322 | printk(KERN_INFO "simeth_device_event: %s ipaddr=0x%x\n", | |
a144ea4b | 323 | dev->name, ntohl(ifa->ifa_local)); |
1da177e4 LT |
324 | |
325 | /* | |
326 | * XXX Fix me | |
327 | * if the device was up, and we're simply reconfiguring it, not sure | |
328 | * we get DOWN then UP. | |
329 | */ | |
330 | ||
331 | local = dev->priv; | |
332 | /* now do it for real */ | |
333 | r = event == NETDEV_UP ? | |
a144ea4b | 334 | netdev_attach(local->simfd, dev->irq, ntohl(ifa->ifa_local)): |
1da177e4 LT |
335 | netdev_detach(local->simfd); |
336 | ||
337 | printk(KERN_INFO "simeth: netdev_attach/detach: event=%s ->%d\n", | |
338 | event == NETDEV_UP ? "attach":"detach", r); | |
339 | ||
340 | return NOTIFY_DONE; | |
341 | } | |
342 | ||
343 | static int | |
344 | simeth_close(struct net_device *dev) | |
345 | { | |
346 | netif_stop_queue(dev); | |
347 | ||
348 | free_irq(dev->irq, dev); | |
349 | ||
350 | return 0; | |
351 | } | |
352 | ||
353 | /* | |
354 | * Only used for debug | |
355 | */ | |
356 | static void | |
357 | frame_print(unsigned char *from, unsigned char *frame, int len) | |
358 | { | |
359 | int i; | |
360 | ||
361 | printk("%s: (%d) %02x", from, len, frame[0] & 0xff); | |
362 | for(i=1; i < 6; i++ ) { | |
363 | printk(":%02x", frame[i] &0xff); | |
364 | } | |
365 | printk(" %2x", frame[6] &0xff); | |
366 | for(i=7; i < 12; i++ ) { | |
367 | printk(":%02x", frame[i] &0xff); | |
368 | } | |
369 | printk(" [%02x%02x]\n", frame[12], frame[13]); | |
370 | ||
371 | for(i=14; i < len; i++ ) { | |
372 | printk("%02x ", frame[i] &0xff); | |
373 | if ( (i%10)==0) printk("\n"); | |
374 | } | |
375 | printk("\n"); | |
376 | } | |
377 | ||
378 | ||
379 | /* | |
380 | * Function used to transmit of frame, very last one on the path before | |
381 | * going to the simulator. | |
382 | */ | |
383 | static int | |
384 | simeth_tx(struct sk_buff *skb, struct net_device *dev) | |
385 | { | |
386 | struct simeth_local *local = dev->priv; | |
387 | ||
388 | #if 0 | |
389 | /* ensure we have at least ETH_ZLEN bytes (min frame size) */ | |
390 | unsigned int length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN; | |
391 | /* Where do the extra padding bytes comes from inthe skbuff ? */ | |
392 | #else | |
393 | /* the real driver in the host system is going to take care of that | |
394 | * or maybe it's the NIC itself. | |
395 | */ | |
396 | unsigned int length = skb->len; | |
397 | #endif | |
398 | ||
399 | local->stats.tx_bytes += skb->len; | |
400 | local->stats.tx_packets++; | |
401 | ||
402 | ||
403 | if (simeth_debug > 5) frame_print("simeth_tx", skb->data, length); | |
404 | ||
405 | netdev_send(local->simfd, skb->data, length); | |
406 | ||
407 | /* | |
408 | * we are synchronous on write, so we don't simulate a | |
409 | * trasnmit complete interrupt, thus we don't need to arm a tx | |
410 | */ | |
411 | ||
412 | dev_kfree_skb(skb); | |
413 | return 0; | |
414 | } | |
415 | ||
416 | static inline struct sk_buff * | |
417 | make_new_skb(struct net_device *dev) | |
418 | { | |
419 | struct sk_buff *nskb; | |
420 | ||
421 | /* | |
422 | * The +2 is used to make sure that the IP header is nicely | |
423 | * aligned (on 4byte boundary I assume 14+2=16) | |
424 | */ | |
425 | nskb = dev_alloc_skb(SIMETH_FRAME_SIZE + 2); | |
426 | if ( nskb == NULL ) { | |
427 | printk(KERN_NOTICE "%s: memory squeeze. dropping packet.\n", dev->name); | |
428 | return NULL; | |
429 | } | |
430 | nskb->dev = dev; | |
431 | ||
432 | skb_reserve(nskb, 2); /* Align IP on 16 byte boundaries */ | |
433 | ||
434 | skb_put(nskb,SIMETH_FRAME_SIZE); | |
435 | ||
436 | return nskb; | |
437 | } | |
438 | ||
439 | /* | |
440 | * called from interrupt handler to process a received frame | |
441 | */ | |
442 | static int | |
443 | simeth_rx(struct net_device *dev) | |
444 | { | |
445 | struct simeth_local *local; | |
446 | struct sk_buff *skb; | |
447 | int len; | |
448 | int rcv_count = SIMETH_RECV_MAX; | |
449 | ||
450 | local = dev->priv; | |
451 | /* | |
452 | * the loop concept has been borrowed from other drivers | |
453 | * looks to me like it's a throttling thing to avoid pushing to many | |
454 | * packets at one time into the stack. Making sure we can process them | |
455 | * upstream and make forward progress overall | |
456 | */ | |
457 | do { | |
458 | if ( (skb=make_new_skb(dev)) == NULL ) { | |
459 | printk(KERN_NOTICE "%s: memory squeeze. dropping packet.\n", dev->name); | |
460 | local->stats.rx_dropped++; | |
461 | return 0; | |
462 | } | |
463 | /* | |
464 | * Read only one frame at a time | |
465 | */ | |
466 | len = netdev_read(local->simfd, skb->data, SIMETH_FRAME_SIZE); | |
467 | if ( len == 0 ) { | |
468 | if ( simeth_debug > 0 ) printk(KERN_WARNING "%s: count=%d netdev_read=0\n", | |
469 | dev->name, SIMETH_RECV_MAX-rcv_count); | |
470 | break; | |
471 | } | |
472 | #if 0 | |
473 | /* | |
474 | * XXX Fix me | |
475 | * Should really do a csum+copy here | |
476 | */ | |
477 | memcpy(skb->data, frame, len); | |
478 | #endif | |
479 | skb->protocol = eth_type_trans(skb, dev); | |
480 | ||
481 | if ( simeth_debug > 6 ) frame_print("simeth_rx", skb->data, len); | |
482 | ||
483 | /* | |
484 | * push the packet up & trigger software interrupt | |
485 | */ | |
486 | netif_rx(skb); | |
487 | ||
488 | local->stats.rx_packets++; | |
489 | local->stats.rx_bytes += len; | |
490 | ||
491 | } while ( --rcv_count ); | |
492 | ||
493 | return len; /* 0 = nothing left to read, otherwise, we can try again */ | |
494 | } | |
495 | ||
496 | /* | |
497 | * Interrupt handler (Yes, we can do it too !!!) | |
498 | */ | |
499 | static irqreturn_t | |
500 | simeth_interrupt(int irq, void *dev_id, struct pt_regs * regs) | |
501 | { | |
502 | struct net_device *dev = dev_id; | |
503 | ||
504 | if ( dev == NULL ) { | |
505 | printk(KERN_WARNING "simeth: irq %d for unknown device\n", irq); | |
506 | return IRQ_NONE; | |
507 | } | |
508 | ||
509 | /* | |
510 | * very simple loop because we get interrupts only when receiving | |
511 | */ | |
512 | while (simeth_rx(dev)); | |
513 | return IRQ_HANDLED; | |
514 | } | |
515 | ||
516 | static struct net_device_stats * | |
517 | simeth_get_stats(struct net_device *dev) | |
518 | { | |
519 | struct simeth_local *local = dev->priv; | |
520 | ||
521 | return &local->stats; | |
522 | } | |
523 | ||
524 | /* fake multicast ability */ | |
525 | static void | |
526 | set_multicast_list(struct net_device *dev) | |
527 | { | |
528 | printk(KERN_WARNING "%s: set_multicast_list called\n", dev->name); | |
529 | } | |
530 | ||
531 | __initcall(simeth_probe); |