1 // SPDX-License-Identifier: GPL-2.0-or-later
4 * arch/xtensa/platforms/iss/network.c
6 * Platform specific initialization.
8 * Authors: Chris Zankel <chris@zankel.net>
9 * Based on work form the UML team.
11 * Copyright 2005 Tensilica Inc.
14 #define pr_fmt(fmt) "%s: " fmt, __func__
16 #include <linux/list.h>
17 #include <linux/irq.h>
18 #include <linux/spinlock.h>
19 #include <linux/slab.h>
20 #include <linux/timer.h>
21 #include <linux/if_ether.h>
22 #include <linux/inetdevice.h>
23 #include <linux/init.h>
24 #include <linux/if_tun.h>
25 #include <linux/etherdevice.h>
26 #include <linux/interrupt.h>
27 #include <linux/ioctl.h>
28 #include <linux/memblock.h>
29 #include <linux/ethtool.h>
30 #include <linux/rtnetlink.h>
31 #include <linux/platform_device.h>
33 #include <platform/simcall.h>
35 #define DRIVER_NAME "iss-netdev"
36 #define ETH_MAX_PACKET 1500
37 #define ETH_HEADER_OTHER 14
38 #define ISS_NET_TIMER_VALUE (HZ / 10)
41 static DEFINE_SPINLOCK(opened_lock);
42 static LIST_HEAD(opened);
44 static DEFINE_SPINLOCK(devices_lock);
45 static LIST_HEAD(devices);
47 /* ------------------------------------------------------------------------- */
49 /* We currently only support the TUNTAP transport protocol. */
51 #define TRANSPORT_TUNTAP_NAME "tuntap"
52 #define TRANSPORT_TUNTAP_MTU ETH_MAX_PACKET
55 char dev_name[IFNAMSIZ];
59 /* ------------------------------------------------------------------------- */
62 /* This structure contains out private information for the driver. */
64 struct iss_net_private {
65 struct list_head device_list;
66 struct list_head opened_list;
69 struct net_device *dev;
70 struct platform_device pdev;
72 struct net_device_stats stats;
74 struct timer_list timer;
75 unsigned int timer_val;
82 struct tuntap_info tuntap;
85 int (*open)(struct iss_net_private *lp);
86 void (*close)(struct iss_net_private *lp);
87 int (*read)(struct iss_net_private *lp, struct sk_buff **skb);
88 int (*write)(struct iss_net_private *lp, struct sk_buff **skb);
89 unsigned short (*protocol)(struct sk_buff *skb);
90 int (*poll)(struct iss_net_private *lp);
95 /* ================================ HELPERS ================================ */
98 static char *split_if_spec(char *str, ...)
104 while ((arg = va_arg(ap, char**)) != NULL) {
109 end = strchr(str, ',');
123 /* Set Ethernet address of the specified device. */
125 static void setup_etheraddr(struct net_device *dev, char *str)
127 unsigned char *addr = dev->dev_addr;
132 if (!mac_pton(str, addr)) {
133 pr_err("%s: failed to parse '%s' as an ethernet address\n",
137 if (is_multicast_ether_addr(addr)) {
138 pr_err("%s: attempt to assign a multicast ethernet address\n",
142 if (!is_valid_ether_addr(addr)) {
143 pr_err("%s: attempt to assign an invalid ethernet address\n",
147 if (!is_local_ether_addr(addr))
148 pr_warn("%s: assigning a globally valid ethernet address\n",
153 pr_info("%s: choosing a random ethernet address\n",
155 eth_hw_addr_random(dev);
158 /* ======================= TUNTAP TRANSPORT INTERFACE ====================== */
160 static int tuntap_open(struct iss_net_private *lp)
163 char *dev_name = lp->tp.info.tuntap.dev_name;
167 fd = simc_open("/dev/net/tun", 02, 0); /* O_RDWR */
169 pr_err("%s: failed to open /dev/net/tun, returned %d (errno = %d)\n",
170 lp->dev->name, fd, errno);
174 memset(&ifr, 0, sizeof(ifr));
175 ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
176 strlcpy(ifr.ifr_name, dev_name, sizeof(ifr.ifr_name));
178 err = simc_ioctl(fd, TUNSETIFF, &ifr);
180 pr_err("%s: failed to set interface %s, returned %d (errno = %d)\n",
181 lp->dev->name, dev_name, err, errno);
186 lp->tp.info.tuntap.fd = fd;
190 static void tuntap_close(struct iss_net_private *lp)
192 simc_close(lp->tp.info.tuntap.fd);
193 lp->tp.info.tuntap.fd = -1;
196 static int tuntap_read(struct iss_net_private *lp, struct sk_buff **skb)
198 return simc_read(lp->tp.info.tuntap.fd,
199 (*skb)->data, (*skb)->dev->mtu + ETH_HEADER_OTHER);
202 static int tuntap_write(struct iss_net_private *lp, struct sk_buff **skb)
204 return simc_write(lp->tp.info.tuntap.fd, (*skb)->data, (*skb)->len);
207 static unsigned short tuntap_protocol(struct sk_buff *skb)
209 return eth_type_trans(skb, skb->dev);
212 static int tuntap_poll(struct iss_net_private *lp)
214 return simc_poll(lp->tp.info.tuntap.fd);
218 * ethX=tuntap,[mac address],device name
221 static int tuntap_probe(struct iss_net_private *lp, int index, char *init)
223 struct net_device *dev = lp->dev;
224 char *dev_name = NULL, *mac_str = NULL, *rem = NULL;
226 /* Transport should be 'tuntap': ethX=tuntap,mac,dev_name */
228 if (strncmp(init, TRANSPORT_TUNTAP_NAME,
229 sizeof(TRANSPORT_TUNTAP_NAME) - 1))
232 init += sizeof(TRANSPORT_TUNTAP_NAME) - 1;
234 rem = split_if_spec(init + 1, &mac_str, &dev_name, NULL);
236 pr_err("%s: extra garbage on specification : '%s'\n",
240 } else if (*init != '\0') {
241 pr_err("%s: invalid argument: %s. Skipping device!\n",
247 pr_err("%s: missing tuntap device name\n", dev->name);
251 strlcpy(lp->tp.info.tuntap.dev_name, dev_name,
252 sizeof(lp->tp.info.tuntap.dev_name));
254 setup_etheraddr(dev, mac_str);
256 lp->mtu = TRANSPORT_TUNTAP_MTU;
258 lp->tp.info.tuntap.fd = -1;
260 lp->tp.open = tuntap_open;
261 lp->tp.close = tuntap_close;
262 lp->tp.read = tuntap_read;
263 lp->tp.write = tuntap_write;
264 lp->tp.protocol = tuntap_protocol;
265 lp->tp.poll = tuntap_poll;
270 /* ================================ ISS NET ================================ */
272 static int iss_net_rx(struct net_device *dev)
274 struct iss_net_private *lp = netdev_priv(dev);
278 /* Check if there is any new data. */
280 if (lp->tp.poll(lp) == 0)
283 /* Try to allocate memory, if it fails, try again next round. */
285 skb = dev_alloc_skb(dev->mtu + 2 + ETH_HEADER_OTHER);
287 lp->stats.rx_dropped++;
296 skb_reset_mac_header(skb);
297 pkt_len = lp->tp.read(lp, &skb);
298 skb_put(skb, pkt_len);
301 skb_trim(skb, pkt_len);
302 skb->protocol = lp->tp.protocol(skb);
304 lp->stats.rx_bytes += skb->len;
305 lp->stats.rx_packets++;
313 static int iss_net_poll(void)
315 struct list_head *ele;
318 spin_lock(&opened_lock);
320 list_for_each(ele, &opened) {
321 struct iss_net_private *lp;
323 lp = list_entry(ele, struct iss_net_private, opened_list);
325 if (!netif_running(lp->dev))
328 spin_lock(&lp->lock);
330 while ((err = iss_net_rx(lp->dev)) > 0)
333 spin_unlock(&lp->lock);
336 pr_err("Device '%s' read returned %d, shutting it down\n",
340 /* FIXME reactivate_fd(lp->fd, ISS_ETH_IRQ); */
344 spin_unlock(&opened_lock);
349 static void iss_net_timer(struct timer_list *t)
351 struct iss_net_private *lp = from_timer(lp, t, timer);
354 spin_lock(&lp->lock);
355 mod_timer(&lp->timer, jiffies + lp->timer_val);
356 spin_unlock(&lp->lock);
360 static int iss_net_open(struct net_device *dev)
362 struct iss_net_private *lp = netdev_priv(dev);
365 spin_lock_bh(&lp->lock);
367 err = lp->tp.open(lp);
371 netif_start_queue(dev);
373 /* clear buffer - it can happen that the host side of the interface
374 * is full when we get here. In this case, new data is never queued,
375 * SIGIOs never arrive, and the net never works.
377 while ((err = iss_net_rx(dev)) > 0)
380 spin_unlock_bh(&lp->lock);
381 spin_lock_bh(&opened_lock);
382 list_add(&lp->opened_list, &opened);
383 spin_unlock_bh(&opened_lock);
384 spin_lock_bh(&lp->lock);
386 timer_setup(&lp->timer, iss_net_timer, 0);
387 lp->timer_val = ISS_NET_TIMER_VALUE;
388 mod_timer(&lp->timer, jiffies + lp->timer_val);
391 spin_unlock_bh(&lp->lock);
395 static int iss_net_close(struct net_device *dev)
397 struct iss_net_private *lp = netdev_priv(dev);
398 netif_stop_queue(dev);
399 spin_lock_bh(&lp->lock);
401 spin_lock(&opened_lock);
403 spin_unlock(&opened_lock);
405 del_timer_sync(&lp->timer);
409 spin_unlock_bh(&lp->lock);
413 static int iss_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
415 struct iss_net_private *lp = netdev_priv(dev);
418 netif_stop_queue(dev);
419 spin_lock_bh(&lp->lock);
421 len = lp->tp.write(lp, &skb);
423 if (len == skb->len) {
424 lp->stats.tx_packets++;
425 lp->stats.tx_bytes += skb->len;
426 netif_trans_update(dev);
427 netif_start_queue(dev);
429 /* this is normally done in the interrupt when tx finishes */
430 netif_wake_queue(dev);
432 } else if (len == 0) {
433 netif_start_queue(dev);
434 lp->stats.tx_dropped++;
437 netif_start_queue(dev);
438 pr_err("%s: %s failed(%d)\n", dev->name, __func__, len);
441 spin_unlock_bh(&lp->lock);
448 static struct net_device_stats *iss_net_get_stats(struct net_device *dev)
450 struct iss_net_private *lp = netdev_priv(dev);
454 static void iss_net_set_multicast_list(struct net_device *dev)
458 static void iss_net_tx_timeout(struct net_device *dev)
462 static int iss_net_set_mac(struct net_device *dev, void *addr)
464 struct iss_net_private *lp = netdev_priv(dev);
465 struct sockaddr *hwaddr = addr;
467 if (!is_valid_ether_addr(hwaddr->sa_data))
468 return -EADDRNOTAVAIL;
469 spin_lock_bh(&lp->lock);
470 memcpy(dev->dev_addr, hwaddr->sa_data, ETH_ALEN);
471 spin_unlock_bh(&lp->lock);
475 static int iss_net_change_mtu(struct net_device *dev, int new_mtu)
480 static void iss_net_user_timer_expire(struct timer_list *unused)
485 static struct platform_driver iss_net_driver = {
491 static int driver_registered;
493 static const struct net_device_ops iss_netdev_ops = {
494 .ndo_open = iss_net_open,
495 .ndo_stop = iss_net_close,
496 .ndo_get_stats = iss_net_get_stats,
497 .ndo_start_xmit = iss_net_start_xmit,
498 .ndo_validate_addr = eth_validate_addr,
499 .ndo_change_mtu = iss_net_change_mtu,
500 .ndo_set_mac_address = iss_net_set_mac,
501 .ndo_tx_timeout = iss_net_tx_timeout,
502 .ndo_set_rx_mode = iss_net_set_multicast_list,
505 static int iss_net_configure(int index, char *init)
507 struct net_device *dev;
508 struct iss_net_private *lp;
511 dev = alloc_etherdev(sizeof(*lp));
513 pr_err("eth_configure: failed to allocate device\n");
517 /* Initialize private element. */
519 lp = netdev_priv(dev);
520 *lp = (struct iss_net_private) {
521 .device_list = LIST_HEAD_INIT(lp->device_list),
522 .opened_list = LIST_HEAD_INIT(lp->opened_list),
527 spin_lock_init(&lp->lock);
529 * If this name ends up conflicting with an existing registered
530 * netdevice, that is OK, register_netdev{,ice}() will notice this
533 snprintf(dev->name, sizeof(dev->name), "eth%d", index);
536 * Try all transport protocols.
537 * Note: more protocols can be added by adding '&& !X_init(lp, eth)'.
540 if (!tuntap_probe(lp, index, init)) {
541 pr_err("%s: invalid arguments. Skipping device!\n",
546 pr_info("Netdevice %d (%pM)\n", index, dev->dev_addr);
550 if (!driver_registered) {
551 platform_driver_register(&iss_net_driver);
552 driver_registered = 1;
555 spin_lock(&devices_lock);
556 list_add(&lp->device_list, &devices);
557 spin_unlock(&devices_lock);
560 lp->pdev.name = DRIVER_NAME;
561 platform_device_register(&lp->pdev);
562 SET_NETDEV_DEV(dev, &lp->pdev.dev);
564 dev->netdev_ops = &iss_netdev_ops;
566 dev->watchdog_timeo = (HZ >> 1);
570 err = register_netdevice(dev);
574 pr_err("%s: error registering net device!\n", dev->name);
575 /* XXX: should we call ->remove() here? */
580 timer_setup(&lp->tl, iss_net_user_timer_expire, 0);
585 /* FIXME: unregister; free, etc.. */
589 /* ------------------------------------------------------------------------- */
591 /* Filled in during early boot */
593 struct list_head eth_cmd_line = LIST_HEAD_INIT(eth_cmd_line);
595 struct iss_net_init {
596 struct list_head list;
597 char *init; /* init string */
602 * Parse the command line and look for 'ethX=...' fields, and register all
603 * those fields. They will be later initialized in iss_net_init.
606 static int __init iss_net_setup(char *str)
608 struct iss_net_private *device = NULL;
609 struct iss_net_init *new;
610 struct list_head *ele;
615 end = strchr(str, '=');
617 pr_err("Expected '=' after device number\n");
621 rc = kstrtouint(str, 0, &n);
624 pr_err("Failed to parse '%s'\n", str);
629 spin_lock(&devices_lock);
631 list_for_each(ele, &devices) {
632 device = list_entry(ele, struct iss_net_private, device_list);
633 if (device->index == n)
637 spin_unlock(&devices_lock);
639 if (device && device->index == n) {
640 pr_err("Device %u already configured\n", n);
644 new = memblock_alloc(sizeof(*new), SMP_CACHE_BYTES);
646 pr_err("Alloc_bootmem failed\n");
650 INIT_LIST_HEAD(&new->list);
654 list_add_tail(&new->list, ð_cmd_line);
658 __setup("eth", iss_net_setup);
661 * Initialize all ISS Ethernet devices previously registered in iss_net_setup.
664 static int iss_net_init(void)
666 struct list_head *ele, *next;
668 /* Walk through all Ethernet devices specified in the command line. */
670 list_for_each_safe(ele, next, ð_cmd_line) {
671 struct iss_net_init *eth;
672 eth = list_entry(ele, struct iss_net_init, list);
673 iss_net_configure(eth->index, eth->init);
678 device_initcall(iss_net_init);