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)
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",
150 eth_hw_addr_set(dev, addr);
154 pr_info("%s: choosing a random ethernet address\n",
156 eth_hw_addr_random(dev);
159 /* ======================= TUNTAP TRANSPORT INTERFACE ====================== */
161 static int tuntap_open(struct iss_net_private *lp)
164 char *dev_name = lp->tp.info.tuntap.dev_name;
168 fd = simc_open("/dev/net/tun", 02, 0); /* O_RDWR */
170 pr_err("%s: failed to open /dev/net/tun, returned %d (errno = %d)\n",
171 lp->dev->name, fd, errno);
175 memset(&ifr, 0, sizeof(ifr));
176 ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
177 strscpy(ifr.ifr_name, dev_name, sizeof(ifr.ifr_name));
179 err = simc_ioctl(fd, TUNSETIFF, &ifr);
181 pr_err("%s: failed to set interface %s, returned %d (errno = %d)\n",
182 lp->dev->name, dev_name, err, errno);
187 lp->tp.info.tuntap.fd = fd;
191 static void tuntap_close(struct iss_net_private *lp)
193 simc_close(lp->tp.info.tuntap.fd);
194 lp->tp.info.tuntap.fd = -1;
197 static int tuntap_read(struct iss_net_private *lp, struct sk_buff **skb)
199 return simc_read(lp->tp.info.tuntap.fd,
200 (*skb)->data, (*skb)->dev->mtu + ETH_HEADER_OTHER);
203 static int tuntap_write(struct iss_net_private *lp, struct sk_buff **skb)
205 return simc_write(lp->tp.info.tuntap.fd, (*skb)->data, (*skb)->len);
208 unsigned short tuntap_protocol(struct sk_buff *skb)
210 return eth_type_trans(skb, skb->dev);
213 static int tuntap_poll(struct iss_net_private *lp)
215 return simc_poll(lp->tp.info.tuntap.fd);
219 * ethX=tuntap,[mac address],device name
222 static int tuntap_probe(struct iss_net_private *lp, int index, char *init)
224 struct net_device *dev = lp->dev;
225 char *dev_name = NULL, *mac_str = NULL, *rem = NULL;
227 /* Transport should be 'tuntap': ethX=tuntap,mac,dev_name */
229 if (strncmp(init, TRANSPORT_TUNTAP_NAME,
230 sizeof(TRANSPORT_TUNTAP_NAME) - 1))
233 init += sizeof(TRANSPORT_TUNTAP_NAME) - 1;
235 rem = split_if_spec(init + 1, &mac_str, &dev_name);
237 pr_err("%s: extra garbage on specification : '%s'\n",
241 } else if (*init != '\0') {
242 pr_err("%s: invalid argument: %s. Skipping device!\n",
248 pr_err("%s: missing tuntap device name\n", dev->name);
252 strscpy(lp->tp.info.tuntap.dev_name, dev_name,
253 sizeof(lp->tp.info.tuntap.dev_name));
255 setup_etheraddr(dev, mac_str);
257 lp->mtu = TRANSPORT_TUNTAP_MTU;
259 lp->tp.info.tuntap.fd = -1;
261 lp->tp.open = tuntap_open;
262 lp->tp.close = tuntap_close;
263 lp->tp.read = tuntap_read;
264 lp->tp.write = tuntap_write;
265 lp->tp.protocol = tuntap_protocol;
266 lp->tp.poll = tuntap_poll;
271 /* ================================ ISS NET ================================ */
273 static int iss_net_rx(struct net_device *dev)
275 struct iss_net_private *lp = netdev_priv(dev);
279 /* Check if there is any new data. */
281 if (lp->tp.poll(lp) == 0)
284 /* Try to allocate memory, if it fails, try again next round. */
286 skb = dev_alloc_skb(dev->mtu + 2 + ETH_HEADER_OTHER);
288 lp->stats.rx_dropped++;
297 skb_reset_mac_header(skb);
298 pkt_len = lp->tp.read(lp, &skb);
299 skb_put(skb, pkt_len);
302 skb_trim(skb, pkt_len);
303 skb->protocol = lp->tp.protocol(skb);
305 lp->stats.rx_bytes += skb->len;
306 lp->stats.rx_packets++;
314 static int iss_net_poll(void)
316 struct list_head *ele;
319 spin_lock(&opened_lock);
321 list_for_each(ele, &opened) {
322 struct iss_net_private *lp;
324 lp = list_entry(ele, struct iss_net_private, opened_list);
326 if (!netif_running(lp->dev))
329 spin_lock(&lp->lock);
331 while ((err = iss_net_rx(lp->dev)) > 0)
334 spin_unlock(&lp->lock);
337 pr_err("Device '%s' read returned %d, shutting it down\n",
341 /* FIXME reactivate_fd(lp->fd, ISS_ETH_IRQ); */
345 spin_unlock(&opened_lock);
350 static void iss_net_timer(struct timer_list *t)
352 struct iss_net_private *lp = from_timer(lp, t, timer);
355 spin_lock(&lp->lock);
356 mod_timer(&lp->timer, jiffies + lp->timer_val);
357 spin_unlock(&lp->lock);
361 static int iss_net_open(struct net_device *dev)
363 struct iss_net_private *lp = netdev_priv(dev);
366 spin_lock_bh(&lp->lock);
368 err = lp->tp.open(lp);
372 netif_start_queue(dev);
374 /* clear buffer - it can happen that the host side of the interface
375 * is full when we get here. In this case, new data is never queued,
376 * SIGIOs never arrive, and the net never works.
378 while ((err = iss_net_rx(dev)) > 0)
381 spin_unlock_bh(&lp->lock);
382 spin_lock_bh(&opened_lock);
383 list_add(&lp->opened_list, &opened);
384 spin_unlock_bh(&opened_lock);
385 spin_lock_bh(&lp->lock);
387 timer_setup(&lp->timer, iss_net_timer, 0);
388 lp->timer_val = ISS_NET_TIMER_VALUE;
389 mod_timer(&lp->timer, jiffies + lp->timer_val);
392 spin_unlock_bh(&lp->lock);
396 static int iss_net_close(struct net_device *dev)
398 struct iss_net_private *lp = netdev_priv(dev);
399 netif_stop_queue(dev);
400 spin_lock_bh(&lp->lock);
402 spin_lock(&opened_lock);
404 spin_unlock(&opened_lock);
406 del_timer_sync(&lp->timer);
410 spin_unlock_bh(&lp->lock);
414 static int iss_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
416 struct iss_net_private *lp = netdev_priv(dev);
419 netif_stop_queue(dev);
420 spin_lock_bh(&lp->lock);
422 len = lp->tp.write(lp, &skb);
424 if (len == skb->len) {
425 lp->stats.tx_packets++;
426 lp->stats.tx_bytes += skb->len;
427 netif_trans_update(dev);
428 netif_start_queue(dev);
430 /* this is normally done in the interrupt when tx finishes */
431 netif_wake_queue(dev);
433 } else if (len == 0) {
434 netif_start_queue(dev);
435 lp->stats.tx_dropped++;
438 netif_start_queue(dev);
439 pr_err("%s: %s failed(%d)\n", dev->name, __func__, len);
442 spin_unlock_bh(&lp->lock);
449 static struct net_device_stats *iss_net_get_stats(struct net_device *dev)
451 struct iss_net_private *lp = netdev_priv(dev);
455 static void iss_net_set_multicast_list(struct net_device *dev)
459 static void iss_net_tx_timeout(struct net_device *dev, unsigned int txqueue)
463 static int iss_net_set_mac(struct net_device *dev, void *addr)
465 struct iss_net_private *lp = netdev_priv(dev);
466 struct sockaddr *hwaddr = addr;
468 if (!is_valid_ether_addr(hwaddr->sa_data))
469 return -EADDRNOTAVAIL;
470 spin_lock_bh(&lp->lock);
471 eth_hw_addr_set(dev, hwaddr->sa_data);
472 spin_unlock_bh(&lp->lock);
476 static int iss_net_change_mtu(struct net_device *dev, int new_mtu)
481 void iss_net_user_timer_expire(struct timer_list *unused)
486 static struct platform_driver iss_net_driver = {
492 static int driver_registered;
494 static const struct net_device_ops iss_netdev_ops = {
495 .ndo_open = iss_net_open,
496 .ndo_stop = iss_net_close,
497 .ndo_get_stats = iss_net_get_stats,
498 .ndo_start_xmit = iss_net_start_xmit,
499 .ndo_validate_addr = eth_validate_addr,
500 .ndo_change_mtu = iss_net_change_mtu,
501 .ndo_set_mac_address = iss_net_set_mac,
502 .ndo_tx_timeout = iss_net_tx_timeout,
503 .ndo_set_rx_mode = iss_net_set_multicast_list,
506 static int iss_net_configure(int index, char *init)
508 struct net_device *dev;
509 struct iss_net_private *lp;
512 dev = alloc_etherdev(sizeof(*lp));
514 pr_err("eth_configure: failed to allocate device\n");
518 /* Initialize private element. */
520 lp = netdev_priv(dev);
521 *lp = (struct iss_net_private) {
522 .device_list = LIST_HEAD_INIT(lp->device_list),
523 .opened_list = LIST_HEAD_INIT(lp->opened_list),
528 spin_lock_init(&lp->lock);
530 * If this name ends up conflicting with an existing registered
531 * netdevice, that is OK, register_netdev{,ice}() will notice this
534 snprintf(dev->name, sizeof(dev->name), "eth%d", index);
537 * Try all transport protocols.
538 * Note: more protocols can be added by adding '&& !X_init(lp, eth)'.
541 if (!tuntap_probe(lp, index, init)) {
542 pr_err("%s: invalid arguments. Skipping device!\n",
547 pr_info("Netdevice %d (%pM)\n", index, dev->dev_addr);
551 if (!driver_registered) {
552 platform_driver_register(&iss_net_driver);
553 driver_registered = 1;
556 spin_lock(&devices_lock);
557 list_add(&lp->device_list, &devices);
558 spin_unlock(&devices_lock);
561 lp->pdev.name = DRIVER_NAME;
562 platform_device_register(&lp->pdev);
563 SET_NETDEV_DEV(dev, &lp->pdev.dev);
565 dev->netdev_ops = &iss_netdev_ops;
567 dev->watchdog_timeo = (HZ >> 1);
571 err = register_netdevice(dev);
575 pr_err("%s: error registering net device!\n", dev->name);
576 /* XXX: should we call ->remove() here? */
581 timer_setup(&lp->tl, iss_net_user_timer_expire, 0);
586 /* FIXME: unregister; free, etc.. */
590 /* ------------------------------------------------------------------------- */
592 /* Filled in during early boot */
594 struct list_head eth_cmd_line = LIST_HEAD_INIT(eth_cmd_line);
596 struct iss_net_init {
597 struct list_head list;
598 char *init; /* init string */
603 * Parse the command line and look for 'ethX=...' fields, and register all
604 * those fields. They will be later initialized in iss_net_init.
607 static int __init iss_net_setup(char *str)
609 struct iss_net_private *device = NULL;
610 struct iss_net_init *new;
611 struct list_head *ele;
616 end = strchr(str, '=');
618 pr_err("Expected '=' after device number\n");
622 rc = kstrtouint(str, 0, &n);
625 pr_err("Failed to parse '%s'\n", str);
630 spin_lock(&devices_lock);
632 list_for_each(ele, &devices) {
633 device = list_entry(ele, struct iss_net_private, device_list);
634 if (device->index == n)
638 spin_unlock(&devices_lock);
640 if (device && device->index == n) {
641 pr_err("Device %u already configured\n", n);
645 new = memblock_alloc(sizeof(*new), SMP_CACHE_BYTES);
647 pr_err("Alloc_bootmem failed\n");
651 INIT_LIST_HEAD(&new->list);
655 list_add_tail(&new->list, ð_cmd_line);
659 __setup("eth", iss_net_setup);
662 * Initialize all ISS Ethernet devices previously registered in iss_net_setup.
665 static int iss_net_init(void)
667 struct list_head *ele, *next;
669 /* Walk through all Ethernet devices specified in the command line. */
671 list_for_each_safe(ele, next, ð_cmd_line) {
672 struct iss_net_init *eth;
673 eth = list_entry(ele, struct iss_net_init, list);
674 iss_net_configure(eth->index, eth->init);
679 device_initcall(iss_net_init);