1 /* 3c527.c: 3Com Etherlink/MC32 driver for Linux 2.4 and 2.6.
3 * (c) Copyright 1998 Red Hat Software Inc
5 * Further debugging by Carl Drougge.
6 * Initial SMP support by Felipe W Damasio <felipewd@terra.com.br>
7 * Heavily modified by Richard Procter <rnp@paradise.net.nz>
9 * Based on skeleton.c written 1993-94 by Donald Becker and ne2.c
10 * (for the MCA stuff) written by Wim Dumon.
12 * Thanks to 3Com for making this possible by providing me with the
15 * This software may be used and distributed according to the terms
16 * of the GNU General Public License, incorporated herein by reference.
20 #define DRV_NAME "3c527"
21 #define DRV_VERSION "0.7-SMP"
22 #define DRV_RELDATE "2003/09/21"
24 static const char *version =
25 DRV_NAME ".c:v" DRV_VERSION " " DRV_RELDATE " Richard Procter <rnp@paradise.net.nz>\n";
28 * DOC: Traps for the unwary
30 * The diagram (Figure 1-1) and the POS summary disagree with the
31 * "Interrupt Level" section in the manual.
33 * The manual contradicts itself when describing the minimum number
34 * buffers in the 'configure lists' command.
35 * My card accepts a buffer config of 4/4.
37 * Setting the SAV BP bit does not save bad packets, but
38 * only enables RX on-card stats collection.
40 * The documentation in places seems to miss things. In actual fact
41 * I've always eventually found everything is documented, it just
42 * requires careful study.
44 * DOC: Theory Of Operation
46 * The 3com 3c527 is a 32bit MCA bus mastering adapter with a large
47 * amount of on board intelligence that housekeeps a somewhat dumber
48 * Intel NIC. For performance we want to keep the transmit queue deep
49 * as the card can transmit packets while fetching others from main
50 * memory by bus master DMA. Transmission and reception are driven by
51 * circular buffer queues.
53 * The mailboxes can be used for controlling how the card traverses
54 * its buffer rings, but are used only for inital setup in this
55 * implementation. The exec mailbox allows a variety of commands to
56 * be executed. Each command must complete before the next is
57 * executed. Primarily we use the exec mailbox for controlling the
58 * multicast lists. We have to do a certain amount of interesting
59 * hoop jumping as the multicast list changes can occur in interrupt
60 * state when the card has an exec command pending. We defer such
61 * events until the command completion interrupt.
63 * A copy break scheme (taken from 3c59x.c) is employed whereby
64 * received frames exceeding a configurable length are passed
65 * directly to the higher networking layers without incuring a copy,
66 * in what amounts to a time/space trade-off.
68 * The card also keeps a large amount of statistical information
69 * on-board. In a perfect world, these could be used safely at no
70 * cost. However, lacking information to the contrary, processing
71 * them without races would involve so much extra complexity as to
72 * make it unworthwhile to do so. In the end, a hybrid SW/HW
73 * implementation was made necessary --- see mc32_update_stats().
77 * It should be possible to use two or more cards, but at this stage
78 * only by loading two copies of the same module.
80 * The on-board 82586 NIC has trouble receiving multiple
81 * back-to-back frames and so is likely to drop packets from fast
85 #include <linux/module.h>
87 #include <linux/errno.h>
88 #include <linux/netdevice.h>
89 #include <linux/etherdevice.h>
90 #include <linux/if_ether.h>
91 #include <linux/init.h>
92 #include <linux/kernel.h>
93 #include <linux/types.h>
94 #include <linux/fcntl.h>
95 #include <linux/interrupt.h>
96 #include <linux/mca-legacy.h>
97 #include <linux/ioport.h>
99 #include <linux/skbuff.h>
100 #include <linux/slab.h>
101 #include <linux/string.h>
102 #include <linux/wait.h>
103 #include <linux/ethtool.h>
104 #include <linux/completion.h>
105 #include <linux/bitops.h>
107 #include <asm/semaphore.h>
108 #include <asm/uaccess.h>
109 #include <asm/system.h>
115 MODULE_LICENSE("GPL");
118 * The name of the card. Is used for messages and in the requests for
119 * io regions, irqs and dma channels
121 static const char* cardname = DRV_NAME;
123 /* use 0 for production, 1 for verification, >2 for debug */
130 static unsigned int mc32_debug = NET_DEBUG;
132 /* The number of low I/O ports used by the ethercard. */
133 #define MC32_IO_EXTENT 8
135 /* As implemented, values must be a power-of-2 -- 4/8/16/32 */
136 #define TX_RING_LEN 32 /* Typically the card supports 37 */
137 #define RX_RING_LEN 8 /* " " " */
139 /* Copy break point, see above for details.
140 * Setting to > 1512 effectively disables this feature. */
141 #define RX_COPYBREAK 200 /* Value from 3c59x.c */
143 /* Issue the 82586 workaround command - this is for "busy lans", but
144 * basically means for all lans now days - has a performance (latency)
145 * cost, but best set. */
146 static const int WORKAROUND_82586=1;
148 /* Pointers to buffers and their on-card records */
149 struct mc32_ring_desc
151 volatile struct skb_header *p;
155 /* Information that needs to be kept for each board. */
161 struct net_device_stats net_stats;
162 volatile struct mc32_mailbox *rx_box;
163 volatile struct mc32_mailbox *tx_box;
164 volatile struct mc32_mailbox *exec_box;
165 volatile struct mc32_stats *stats; /* Start of on-card statistics */
166 u16 tx_chain; /* Transmit list start offset */
167 u16 rx_chain; /* Receive list start offset */
168 u16 tx_len; /* Transmit list count */
169 u16 rx_len; /* Receive list count */
171 u16 xceiver_desired_state; /* HALTED or RUNNING */
172 u16 cmd_nonblocking; /* Thread is uninterested in command result */
173 u16 mc_reload_wait; /* A multicast load request is pending */
174 u32 mc_list_valid; /* True when the mclist is set */
176 struct mc32_ring_desc tx_ring[TX_RING_LEN]; /* Host Transmit ring */
177 struct mc32_ring_desc rx_ring[RX_RING_LEN]; /* Host Receive ring */
179 atomic_t tx_count; /* buffers left */
180 atomic_t tx_ring_head; /* index to tx en-queue end */
181 u16 tx_ring_tail; /* index to tx de-queue end */
183 u16 rx_ring_tail; /* index to rx de-queue end */
185 struct semaphore cmd_mutex; /* Serialises issuing of execute commands */
186 struct completion execution_cmd; /* Card has completed an execute command */
187 struct completion xceiver_cmd; /* Card has completed a tx or rx command */
190 /* The station (ethernet) address prefix, used for a sanity check. */
191 #define SA_ADDR0 0x02
192 #define SA_ADDR1 0x60
193 #define SA_ADDR2 0xAC
195 struct mca_adapters_t {
200 static const struct mca_adapters_t mc32_adapters[] = {
201 { 0x0041, "3COM EtherLink MC/32" },
202 { 0x8EF5, "IBM High Performance Lan Adapter" },
207 /* Macros for ring index manipulations */
208 static inline u16 next_rx(u16 rx) { return (rx+1)&(RX_RING_LEN-1); };
209 static inline u16 prev_rx(u16 rx) { return (rx-1)&(RX_RING_LEN-1); };
211 static inline u16 next_tx(u16 tx) { return (tx+1)&(TX_RING_LEN-1); };
214 /* Index to functions, as function prototypes. */
215 static int mc32_probe1(struct net_device *dev, int ioaddr);
216 static int mc32_command(struct net_device *dev, u16 cmd, void *data, int len);
217 static int mc32_open(struct net_device *dev);
218 static void mc32_timeout(struct net_device *dev);
219 static int mc32_send_packet(struct sk_buff *skb, struct net_device *dev);
220 static irqreturn_t mc32_interrupt(int irq, void *dev_id, struct pt_regs *regs);
221 static int mc32_close(struct net_device *dev);
222 static struct net_device_stats *mc32_get_stats(struct net_device *dev);
223 static void mc32_set_multicast_list(struct net_device *dev);
224 static void mc32_reset_multicast_list(struct net_device *dev);
225 static struct ethtool_ops netdev_ethtool_ops;
227 static void cleanup_card(struct net_device *dev)
229 struct mc32_local *lp = netdev_priv(dev);
230 unsigned slot = lp->slot;
231 mca_mark_as_unused(slot);
232 mca_set_adapter_name(slot, NULL);
233 free_irq(dev->irq, dev);
234 release_region(dev->base_addr, MC32_IO_EXTENT);
238 * mc32_probe - Search for supported boards
239 * @unit: interface number to use
241 * Because MCA bus is a real bus and we can scan for cards we could do a
242 * single scan for all boards here. Right now we use the passed in device
243 * structure and scan for only one board. This needs fixing for modules
247 struct net_device *__init mc32_probe(int unit)
249 struct net_device *dev = alloc_etherdev(sizeof(struct mc32_local));
250 static int current_mca_slot = -1;
255 return ERR_PTR(-ENOMEM);
258 sprintf(dev->name, "eth%d", unit);
260 SET_MODULE_OWNER(dev);
262 /* Do not check any supplied i/o locations.
263 POS registers usually don't fail :) */
265 /* MCA cards have POS registers.
266 Autodetecting MCA cards is extremely simple.
267 Just search for the card. */
269 for(i = 0; (mc32_adapters[i].name != NULL); i++) {
271 mca_find_unused_adapter(mc32_adapters[i].id, 0);
273 if(current_mca_slot != MCA_NOTFOUND) {
274 if(!mc32_probe1(dev, current_mca_slot))
276 mca_set_adapter_name(current_mca_slot,
277 mc32_adapters[i].name);
278 mca_mark_as_used(current_mca_slot);
279 err = register_netdev(dev);
291 return ERR_PTR(-ENODEV);
295 * mc32_probe1 - Check a given slot for a board and test the card
296 * @dev: Device structure to fill in
297 * @slot: The MCA bus slot being used by this card
299 * Decode the slot data and configure the card structures. Having done this we
300 * can reset the card and configure it. The card does a full self test cycle
301 * in firmware so we have to wait for it to return and post us either a
302 * failure case or some addresses we use to find the board internals.
305 static int __init mc32_probe1(struct net_device *dev, int slot)
307 static unsigned version_printed;
311 struct mc32_local *lp = netdev_priv(dev);
312 static u16 mca_io_bases[]={
318 static u32 mca_mem_bases[]={
328 static char *failures[]={
329 "Processor instruction",
330 "Processor data bus",
331 "Processor data bus",
332 "Processor data bus",
337 "82586 internal loopback",
338 "82586 initialisation failure",
339 "Adapter list configuration error"
342 /* Time to play MCA games */
344 if (mc32_debug && version_printed++ == 0)
345 printk(KERN_DEBUG "%s", version);
347 printk(KERN_INFO "%s: %s found in slot %d:", dev->name, cardname, slot);
349 POS = mca_read_stored_pos(slot, 2);
353 printk(" disabled.\n");
357 /* Fill in the 'dev' fields. */
358 dev->base_addr = mca_io_bases[(POS>>1)&7];
359 dev->mem_start = mca_mem_bases[(POS>>4)&7];
361 POS = mca_read_stored_pos(slot, 4);
364 printk("memory window disabled.\n");
368 POS = mca_read_stored_pos(slot, 5);
373 printk("invalid memory window.\n");
380 dev->mem_end=dev->mem_start + i;
382 dev->irq = ((POS>>2)&3)+9;
384 if(!request_region(dev->base_addr, MC32_IO_EXTENT, cardname))
386 printk("io 0x%3lX, which is busy.\n", dev->base_addr);
390 printk("io 0x%3lX irq %d mem 0x%lX (%dK)\n",
391 dev->base_addr, dev->irq, dev->mem_start, i/1024);
394 /* We ought to set the cache line size here.. */
401 printk("%s: Address ", dev->name);
403 /* Retrieve and print the ethernet address. */
404 for (i = 0; i < 6; i++)
406 mca_write_pos(slot, 6, i+12);
407 mca_write_pos(slot, 7, 0);
409 printk(" %2.2x", dev->dev_addr[i] = mca_read_pos(slot,3));
412 mca_write_pos(slot, 6, 0);
413 mca_write_pos(slot, 7, 0);
415 POS = mca_read_stored_pos(slot, 4);
418 printk(" : BNC port selected.\n");
420 printk(" : AUI port selected.\n");
422 POS=inb(dev->base_addr+HOST_CTRL);
423 POS|=HOST_CTRL_ATTN|HOST_CTRL_RESET;
424 POS&=~HOST_CTRL_INTE;
425 outb(POS, dev->base_addr+HOST_CTRL);
429 POS&=~(HOST_CTRL_ATTN|HOST_CTRL_RESET);
430 outb(POS, dev->base_addr+HOST_CTRL);
438 err = request_irq(dev->irq, &mc32_interrupt, SA_SHIRQ | SA_SAMPLE_RANDOM, DRV_NAME, dev);
440 release_region(dev->base_addr, MC32_IO_EXTENT);
441 printk(KERN_ERR "%s: unable to get IRQ %d.\n", DRV_NAME, dev->irq);
445 memset(lp, 0, sizeof(struct mc32_local));
450 base = inb(dev->base_addr);
457 printk(KERN_ERR "%s: failed to boot adapter.\n", dev->name);
462 if(inb(dev->base_addr+2)&(1<<5))
463 base = inb(dev->base_addr);
469 printk(KERN_ERR "%s: %s%s.\n", dev->name, failures[base-1],
470 base<0x0A?" test failure":"");
472 printk(KERN_ERR "%s: unknown failure %d.\n", dev->name, base);
482 while(!(inb(dev->base_addr+2)&(1<<5)))
488 printk(KERN_ERR "%s: mailbox read fail (%d).\n", dev->name, i);
494 base|=(inb(dev->base_addr)<<(8*i));
497 lp->exec_box=isa_bus_to_virt(dev->mem_start+base);
499 base=lp->exec_box->data[1]<<16|lp->exec_box->data[0];
501 lp->base = dev->mem_start+base;
503 lp->rx_box=isa_bus_to_virt(lp->base + lp->exec_box->data[2]);
504 lp->tx_box=isa_bus_to_virt(lp->base + lp->exec_box->data[3]);
506 lp->stats = isa_bus_to_virt(lp->base + lp->exec_box->data[5]);
509 * Descriptor chains (card relative)
512 lp->tx_chain = lp->exec_box->data[8]; /* Transmit list start offset */
513 lp->rx_chain = lp->exec_box->data[10]; /* Receive list start offset */
514 lp->tx_len = lp->exec_box->data[9]; /* Transmit list count */
515 lp->rx_len = lp->exec_box->data[11]; /* Receive list count */
517 init_MUTEX_LOCKED(&lp->cmd_mutex);
518 init_completion(&lp->execution_cmd);
519 init_completion(&lp->xceiver_cmd);
521 printk("%s: Firmware Rev %d. %d RX buffers, %d TX buffers. Base of 0x%08X.\n",
522 dev->name, lp->exec_box->data[12], lp->rx_len, lp->tx_len, lp->base);
524 dev->open = mc32_open;
525 dev->stop = mc32_close;
526 dev->hard_start_xmit = mc32_send_packet;
527 dev->get_stats = mc32_get_stats;
528 dev->set_multicast_list = mc32_set_multicast_list;
529 dev->tx_timeout = mc32_timeout;
530 dev->watchdog_timeo = HZ*5; /* Board does all the work */
531 dev->ethtool_ops = &netdev_ethtool_ops;
536 free_irq(dev->irq, dev);
538 release_region(dev->base_addr, MC32_IO_EXTENT);
544 * mc32_ready_poll - wait until we can feed it a command
545 * @dev: The device to wait for
547 * Wait until the card becomes ready to accept a command via the
548 * command register. This tells us nothing about the completion
549 * status of any pending commands and takes very little time at all.
552 static inline void mc32_ready_poll(struct net_device *dev)
554 int ioaddr = dev->base_addr;
555 while(!(inb(ioaddr+HOST_STATUS)&HOST_STATUS_CRR));
560 * mc32_command_nowait - send a command non blocking
561 * @dev: The 3c527 to issue the command to
562 * @cmd: The command word to write to the mailbox
563 * @data: A data block if the command expects one
564 * @len: Length of the data block
566 * Send a command from interrupt state. If there is a command
567 * currently being executed then we return an error of -1. It
568 * simply isn't viable to wait around as commands may be
569 * slow. This can theoretically be starved on SMP, but it's hard
570 * to see a realistic situation. We do not wait for the command
571 * to complete --- we rely on the interrupt handler to tidy up
575 static int mc32_command_nowait(struct net_device *dev, u16 cmd, void *data, int len)
577 struct mc32_local *lp = netdev_priv(dev);
578 int ioaddr = dev->base_addr;
581 if (down_trylock(&lp->cmd_mutex) == 0)
583 lp->cmd_nonblocking=1;
584 lp->exec_box->mbox=0;
585 lp->exec_box->mbox=cmd;
586 memcpy((void *)lp->exec_box->data, data, len);
587 barrier(); /* the memcpy forgot the volatile so be sure */
589 /* Send the command */
590 mc32_ready_poll(dev);
591 outb(1<<6, ioaddr+HOST_CMD);
595 /* Interrupt handler will signal mutex on completion */
603 * mc32_command - send a command and sleep until completion
604 * @dev: The 3c527 card to issue the command to
605 * @cmd: The command word to write to the mailbox
606 * @data: A data block if the command expects one
607 * @len: Length of the data block
609 * Sends exec commands in a user context. This permits us to wait around
610 * for the replies and also to wait for the command buffer to complete
611 * from a previous command before we execute our command. After our
612 * command completes we will attempt any pending multicast reload
613 * we blocked off by hogging the exec buffer.
615 * You feed the card a command, you wait, it interrupts you get a
616 * reply. All well and good. The complication arises because you use
617 * commands for filter list changes which come in at bh level from things
618 * like IPV6 group stuff.
621 static int mc32_command(struct net_device *dev, u16 cmd, void *data, int len)
623 struct mc32_local *lp = netdev_priv(dev);
624 int ioaddr = dev->base_addr;
627 down(&lp->cmd_mutex);
633 lp->cmd_nonblocking=0;
634 lp->exec_box->mbox=0;
635 lp->exec_box->mbox=cmd;
636 memcpy((void *)lp->exec_box->data, data, len);
637 barrier(); /* the memcpy forgot the volatile so be sure */
639 mc32_ready_poll(dev);
640 outb(1<<6, ioaddr+HOST_CMD);
642 wait_for_completion(&lp->execution_cmd);
644 if(lp->exec_box->mbox&(1<<13))
650 * A multicast set got blocked - try it now
653 if(lp->mc_reload_wait)
655 mc32_reset_multicast_list(dev);
663 * mc32_start_transceiver - tell board to restart tx/rx
664 * @dev: The 3c527 card to issue the command to
666 * This may be called from the interrupt state, where it is used
667 * to restart the rx ring if the card runs out of rx buffers.
669 * We must first check if it's ok to (re)start the transceiver. See
670 * mc32_close for details.
673 static void mc32_start_transceiver(struct net_device *dev) {
675 struct mc32_local *lp = netdev_priv(dev);
676 int ioaddr = dev->base_addr;
678 /* Ignore RX overflow on device closure */
679 if (lp->xceiver_desired_state==HALTED)
682 /* Give the card the offset to the post-EOL-bit RX descriptor */
683 mc32_ready_poll(dev);
685 lp->rx_box->data[0]=lp->rx_ring[prev_rx(lp->rx_ring_tail)].p->next;
686 outb(HOST_CMD_START_RX, ioaddr+HOST_CMD);
688 mc32_ready_poll(dev);
690 outb(HOST_CMD_RESTRT_TX, ioaddr+HOST_CMD); /* card ignores this on RX restart */
692 /* We are not interrupted on start completion */
697 * mc32_halt_transceiver - tell board to stop tx/rx
698 * @dev: The 3c527 card to issue the command to
700 * We issue the commands to halt the card's transceiver. In fact,
701 * after some experimenting we now simply tell the card to
702 * suspend. When issuing aborts occasionally odd things happened.
704 * We then sleep until the card has notified us that both rx and
705 * tx have been suspended.
708 static void mc32_halt_transceiver(struct net_device *dev)
710 struct mc32_local *lp = netdev_priv(dev);
711 int ioaddr = dev->base_addr;
713 mc32_ready_poll(dev);
715 outb(HOST_CMD_SUSPND_RX, ioaddr+HOST_CMD);
716 wait_for_completion(&lp->xceiver_cmd);
718 mc32_ready_poll(dev);
720 outb(HOST_CMD_SUSPND_TX, ioaddr+HOST_CMD);
721 wait_for_completion(&lp->xceiver_cmd);
726 * mc32_load_rx_ring - load the ring of receive buffers
727 * @dev: 3c527 to build the ring for
729 * This initalises the on-card and driver datastructures to
730 * the point where mc32_start_transceiver() can be called.
732 * The card sets up the receive ring for us. We are required to use the
733 * ring it provides, although the size of the ring is configurable.
735 * We allocate an sk_buff for each ring entry in turn and
736 * initalise its house-keeping info. At the same time, we read
737 * each 'next' pointer in our rx_ring array. This reduces slow
738 * shared-memory reads and makes it easy to access predecessor
741 * We then set the end-of-list bit for the last entry so that the
742 * card will know when it has run out of buffers.
745 static int mc32_load_rx_ring(struct net_device *dev)
747 struct mc32_local *lp = netdev_priv(dev);
750 volatile struct skb_header *p;
752 rx_base=lp->rx_chain;
754 for(i=0; i<RX_RING_LEN; i++) {
755 lp->rx_ring[i].skb=alloc_skb(1532, GFP_KERNEL);
756 if (lp->rx_ring[i].skb==NULL) {
758 kfree_skb(lp->rx_ring[i].skb);
761 skb_reserve(lp->rx_ring[i].skb, 18);
763 p=isa_bus_to_virt(lp->base+rx_base);
766 p->data=isa_virt_to_bus(lp->rx_ring[i].skb->data);
774 lp->rx_ring[i-1].p->control |= CONTROL_EOL;
783 * mc32_flush_rx_ring - free the ring of receive buffers
784 * @lp: Local data of 3c527 to flush the rx ring of
786 * Free the buffer for each ring slot. This may be called
787 * before mc32_load_rx_ring(), eg. on error in mc32_open().
788 * Requires rx skb pointers to point to a valid skb, or NULL.
791 static void mc32_flush_rx_ring(struct net_device *dev)
793 struct mc32_local *lp = netdev_priv(dev);
796 for(i=0; i < RX_RING_LEN; i++)
798 if (lp->rx_ring[i].skb) {
799 dev_kfree_skb(lp->rx_ring[i].skb);
800 lp->rx_ring[i].skb = NULL;
802 lp->rx_ring[i].p=NULL;
808 * mc32_load_tx_ring - load transmit ring
809 * @dev: The 3c527 card to issue the command to
811 * This sets up the host transmit data-structures.
813 * First, we obtain from the card it's current postion in the tx
814 * ring, so that we will know where to begin transmitting
817 * Then, we read the 'next' pointers from the on-card tx ring into
818 * our tx_ring array to reduce slow shared-mem reads. Finally, we
819 * intitalise the tx house keeping variables.
823 static void mc32_load_tx_ring(struct net_device *dev)
825 struct mc32_local *lp = netdev_priv(dev);
826 volatile struct skb_header *p;
830 tx_base=lp->tx_box->data[0];
832 for(i=0 ; i<TX_RING_LEN ; i++)
834 p=isa_bus_to_virt(lp->base+tx_base);
836 lp->tx_ring[i].skb=NULL;
841 /* -1 so that tx_ring_head cannot "lap" tx_ring_tail */
842 /* see mc32_tx_ring */
844 atomic_set(&lp->tx_count, TX_RING_LEN-1);
845 atomic_set(&lp->tx_ring_head, 0);
851 * mc32_flush_tx_ring - free transmit ring
852 * @lp: Local data of 3c527 to flush the tx ring of
854 * If the ring is non-empty, zip over the it, freeing any
855 * allocated skb_buffs. The tx ring house-keeping variables are
856 * then reset. Requires rx skb pointers to point to a valid skb,
860 static void mc32_flush_tx_ring(struct net_device *dev)
862 struct mc32_local *lp = netdev_priv(dev);
865 for (i=0; i < TX_RING_LEN; i++)
867 if (lp->tx_ring[i].skb)
869 dev_kfree_skb(lp->tx_ring[i].skb);
870 lp->tx_ring[i].skb = NULL;
874 atomic_set(&lp->tx_count, 0);
875 atomic_set(&lp->tx_ring_head, 0);
881 * mc32_open - handle 'up' of card
882 * @dev: device to open
884 * The user is trying to bring the card into ready state. This requires
885 * a brief dialogue with the card. Firstly we enable interrupts and then
886 * 'indications'. Without these enabled the card doesn't bother telling
887 * us what it has done. This had me puzzled for a week.
889 * We configure the number of card descriptors, then load the network
890 * address and multicast filters. Turn on the workaround mode. This
891 * works around a bug in the 82586 - it asks the firmware to do
892 * so. It has a performance (latency) hit but is needed on busy
893 * [read most] lans. We load the ring with buffers then we kick it
897 static int mc32_open(struct net_device *dev)
899 int ioaddr = dev->base_addr;
900 struct mc32_local *lp = netdev_priv(dev);
903 u16 descnumbuffs[2] = {TX_RING_LEN, RX_RING_LEN};
909 regs=inb(ioaddr+HOST_CTRL);
910 regs|=HOST_CTRL_INTE;
911 outb(regs, ioaddr+HOST_CTRL);
914 * Allow ourselves to issue commands
921 * Send the indications on command
924 mc32_command(dev, 4, &one, 2);
927 * Poke it to make sure it's really dead.
930 mc32_halt_transceiver(dev);
931 mc32_flush_tx_ring(dev);
934 * Ask card to set up on-card descriptors to our spec
937 if(mc32_command(dev, 8, descnumbuffs, 4)) {
938 printk("%s: %s rejected our buffer configuration!\n",
939 dev->name, cardname);
944 /* Report new configuration */
945 mc32_command(dev, 6, NULL, 0);
947 lp->tx_chain = lp->exec_box->data[8]; /* Transmit list start offset */
948 lp->rx_chain = lp->exec_box->data[10]; /* Receive list start offset */
949 lp->tx_len = lp->exec_box->data[9]; /* Transmit list count */
950 lp->rx_len = lp->exec_box->data[11]; /* Receive list count */
952 /* Set Network Address */
953 mc32_command(dev, 1, dev->dev_addr, 6);
955 /* Set the filters */
956 mc32_set_multicast_list(dev);
958 if (WORKAROUND_82586) {
960 mc32_command(dev, 0x0D, &zero_word, 2); /* 82586 bug workaround on */
963 mc32_load_tx_ring(dev);
965 if(mc32_load_rx_ring(dev))
971 lp->xceiver_desired_state = RUNNING;
973 /* And finally, set the ball rolling... */
974 mc32_start_transceiver(dev);
976 netif_start_queue(dev);
983 * mc32_timeout - handle a timeout from the network layer
984 * @dev: 3c527 that timed out
986 * Handle a timeout on transmit from the 3c527. This normally means
987 * bad things as the hardware handles cable timeouts and mess for
992 static void mc32_timeout(struct net_device *dev)
994 printk(KERN_WARNING "%s: transmit timed out?\n", dev->name);
995 /* Try to restart the adaptor. */
996 netif_wake_queue(dev);
1001 * mc32_send_packet - queue a frame for transmit
1002 * @skb: buffer to transmit
1003 * @dev: 3c527 to send it out of
1005 * Transmit a buffer. This normally means throwing the buffer onto
1006 * the transmit queue as the queue is quite large. If the queue is
1007 * full then we set tx_busy and return. Once the interrupt handler
1008 * gets messages telling it to reclaim transmit queue entries, we will
1009 * clear tx_busy and the kernel will start calling this again.
1011 * We do not disable interrupts or acquire any locks; this can
1012 * run concurrently with mc32_tx_ring(), and the function itself
1013 * is serialised at a higher layer. However, similarly for the
1014 * card itself, we must ensure that we update tx_ring_head only
1015 * after we've established a valid packet on the tx ring (and
1016 * before we let the card "see" it, to prevent it racing with the
1021 static int mc32_send_packet(struct sk_buff *skb, struct net_device *dev)
1023 struct mc32_local *lp = netdev_priv(dev);
1024 u32 head = atomic_read(&lp->tx_ring_head);
1026 volatile struct skb_header *p, *np;
1028 netif_stop_queue(dev);
1030 if(atomic_read(&lp->tx_count)==0) {
1034 skb = skb_padto(skb, ETH_ZLEN);
1036 netif_wake_queue(dev);
1040 atomic_dec(&lp->tx_count);
1042 /* P is the last sending/sent buffer as a pointer */
1043 p=lp->tx_ring[head].p;
1045 head = next_tx(head);
1047 /* NP is the buffer we will be loading */
1048 np=lp->tx_ring[head].p;
1050 /* We will need this to flush the buffer out */
1051 lp->tx_ring[head].skb=skb;
1053 np->length = unlikely(skb->len < ETH_ZLEN) ? ETH_ZLEN : skb->len;
1054 np->data = isa_virt_to_bus(skb->data);
1056 np->control = CONTROL_EOP | CONTROL_EOL;
1060 * The new frame has been setup; we can now
1061 * let the interrupt handler and card "see" it
1064 atomic_set(&lp->tx_ring_head, head);
1065 p->control &= ~CONTROL_EOL;
1067 netif_wake_queue(dev);
1073 * mc32_update_stats - pull off the on board statistics
1074 * @dev: 3c527 to service
1077 * Query and reset the on-card stats. There's the small possibility
1078 * of a race here, which would result in an underestimation of
1079 * actual errors. As such, we'd prefer to keep all our stats
1080 * collection in software. As a rule, we do. However it can't be
1081 * used for rx errors and collisions as, by default, the card discards
1084 * Setting the SAV BP in the rx filter command supposedly
1085 * stops this behaviour. However, testing shows that it only seems to
1086 * enable the collation of on-card rx statistics --- the driver
1087 * never sees an RX descriptor with an error status set.
1091 static void mc32_update_stats(struct net_device *dev)
1093 struct mc32_local *lp = netdev_priv(dev);
1094 volatile struct mc32_stats *st = lp->stats;
1098 rx_errors+=lp->net_stats.rx_crc_errors +=st->rx_crc_errors;
1099 st->rx_crc_errors=0;
1100 rx_errors+=lp->net_stats.rx_fifo_errors +=st->rx_overrun_errors;
1101 st->rx_overrun_errors=0;
1102 rx_errors+=lp->net_stats.rx_frame_errors +=st->rx_alignment_errors;
1103 st->rx_alignment_errors=0;
1104 rx_errors+=lp->net_stats.rx_length_errors+=st->rx_tooshort_errors;
1105 st->rx_tooshort_errors=0;
1106 rx_errors+=lp->net_stats.rx_missed_errors+=st->rx_outofresource_errors;
1107 st->rx_outofresource_errors=0;
1108 lp->net_stats.rx_errors=rx_errors;
1110 /* Number of packets which saw one collision */
1111 lp->net_stats.collisions+=st->dataC[10];
1114 /* Number of packets which saw 2--15 collisions */
1115 lp->net_stats.collisions+=st->dataC[11];
1121 * mc32_rx_ring - process the receive ring
1122 * @dev: 3c527 that needs its receive ring processing
1125 * We have received one or more indications from the card that a
1126 * receive has completed. The buffer ring thus contains dirty
1127 * entries. We walk the ring by iterating over the circular rx_ring
1128 * array, starting at the next dirty buffer (which happens to be the
1129 * one we finished up at last time around).
1131 * For each completed packet, we will either copy it and pass it up
1132 * the stack or, if the packet is near MTU sized, we allocate
1133 * another buffer and flip the old one up the stack.
1135 * We must succeed in keeping a buffer on the ring. If necessary we
1136 * will toss a received packet rather than lose a ring entry. Once
1137 * the first uncompleted descriptor is found, we move the
1138 * End-Of-List bit to include the buffers just processed.
1142 static void mc32_rx_ring(struct net_device *dev)
1144 struct mc32_local *lp = netdev_priv(dev);
1145 volatile struct skb_header *p;
1150 rx_old_tail = rx_ring_tail = lp->rx_ring_tail;
1154 p=lp->rx_ring[rx_ring_tail].p;
1156 if(!(p->status & (1<<7))) { /* Not COMPLETED */
1159 if(p->status & (1<<6)) /* COMPLETED_OK */
1162 u16 length=p->length;
1163 struct sk_buff *skb;
1164 struct sk_buff *newskb;
1166 /* Try to save time by avoiding a copy on big frames */
1168 if ((length > RX_COPYBREAK)
1169 && ((newskb=dev_alloc_skb(1532)) != NULL))
1171 skb=lp->rx_ring[rx_ring_tail].skb;
1172 skb_put(skb, length);
1174 skb_reserve(newskb,18);
1175 lp->rx_ring[rx_ring_tail].skb=newskb;
1176 p->data=isa_virt_to_bus(newskb->data);
1180 skb=dev_alloc_skb(length+2);
1183 lp->net_stats.rx_dropped++;
1188 memcpy(skb_put(skb, length),
1189 lp->rx_ring[rx_ring_tail].skb->data, length);
1192 skb->protocol=eth_type_trans(skb,dev);
1194 dev->last_rx = jiffies;
1195 lp->net_stats.rx_packets++;
1196 lp->net_stats.rx_bytes += length;
1204 rx_ring_tail=next_rx(rx_ring_tail);
1208 /* If there was actually a frame to be processed, place the EOL bit */
1209 /* at the descriptor prior to the one to be filled next */
1211 if (rx_ring_tail != rx_old_tail)
1213 lp->rx_ring[prev_rx(rx_ring_tail)].p->control |= CONTROL_EOL;
1214 lp->rx_ring[prev_rx(rx_old_tail)].p->control &= ~CONTROL_EOL;
1216 lp->rx_ring_tail=rx_ring_tail;
1222 * mc32_tx_ring - process completed transmits
1223 * @dev: 3c527 that needs its transmit ring processing
1226 * This operates in a similar fashion to mc32_rx_ring. We iterate
1227 * over the transmit ring. For each descriptor which has been
1228 * processed by the card, we free its associated buffer and note
1229 * any errors. This continues until the transmit ring is emptied
1230 * or we reach a descriptor that hasn't yet been processed by the
1235 static void mc32_tx_ring(struct net_device *dev)
1237 struct mc32_local *lp = netdev_priv(dev);
1238 volatile struct skb_header *np;
1241 * We rely on head==tail to mean 'queue empty'.
1242 * This is why lp->tx_count=TX_RING_LEN-1: in order to prevent
1243 * tx_ring_head wrapping to tail and confusing a 'queue empty'
1244 * condition with 'queue full'
1247 while (lp->tx_ring_tail != atomic_read(&lp->tx_ring_head))
1251 t=next_tx(lp->tx_ring_tail);
1252 np=lp->tx_ring[t].p;
1254 if(!(np->status & (1<<7)))
1259 lp->net_stats.tx_packets++;
1260 if(!(np->status & (1<<6))) /* Not COMPLETED_OK */
1262 lp->net_stats.tx_errors++;
1264 switch(np->status&0x0F)
1267 lp->net_stats.tx_aborted_errors++;
1268 break; /* Max collisions */
1270 lp->net_stats.tx_fifo_errors++;
1273 lp->net_stats.tx_carrier_errors++;
1276 lp->net_stats.tx_window_errors++;
1277 break; /* CTS Lost */
1279 lp->net_stats.tx_aborted_errors++;
1280 break; /* Transmit timeout */
1283 /* Packets are sent in order - this is
1284 basically a FIFO queue of buffers matching
1286 lp->net_stats.tx_bytes+=lp->tx_ring[t].skb->len;
1287 dev_kfree_skb_irq(lp->tx_ring[t].skb);
1288 lp->tx_ring[t].skb=NULL;
1289 atomic_inc(&lp->tx_count);
1290 netif_wake_queue(dev);
1299 * mc32_interrupt - handle an interrupt from a 3c527
1300 * @irq: Interrupt number
1301 * @dev_id: 3c527 that requires servicing
1302 * @regs: Registers (unused)
1305 * An interrupt is raised whenever the 3c527 writes to the command
1306 * register. This register contains the message it wishes to send us
1307 * packed into a single byte field. We keep reading status entries
1308 * until we have processed all the control items, but simply count
1309 * transmit and receive reports. When all reports are in we empty the
1310 * transceiver rings as appropriate. This saves the overhead of
1311 * multiple command requests.
1313 * Because MCA is level-triggered, we shouldn't miss indications.
1314 * Therefore, we needn't ask the card to suspend interrupts within
1315 * this handler. The card receives an implicit acknowledgment of the
1316 * current interrupt when we read the command register.
1320 static irqreturn_t mc32_interrupt(int irq, void *dev_id, struct pt_regs * regs)
1322 struct net_device *dev = dev_id;
1323 struct mc32_local *lp;
1324 int ioaddr, status, boguscount = 0;
1329 printk(KERN_WARNING "%s: irq %d for unknown device.\n", cardname, irq);
1333 ioaddr = dev->base_addr;
1334 lp = netdev_priv(dev);
1336 /* See whats cooking */
1338 while((inb(ioaddr+HOST_STATUS)&HOST_STATUS_CWR) && boguscount++<2000)
1340 status=inb(ioaddr+HOST_CMD);
1343 printk("Status TX%d RX%d EX%d OV%d BC%d\n",
1344 (status&7), (status>>3)&7, (status>>6)&1,
1345 (status>>7)&1, boguscount);
1352 case 6: /* TX fail */
1358 complete(&lp->xceiver_cmd);
1361 printk("%s: strange tx ack %d\n", dev->name, status&7);
1373 complete(&lp->xceiver_cmd);
1376 /* Out of RX buffers stat */
1377 /* Must restart rx */
1378 lp->net_stats.rx_dropped++;
1380 mc32_start_transceiver(dev);
1383 printk("%s: strange rx ack %d\n",
1384 dev->name, status&7);
1390 * No thread is waiting: we need to tidy
1394 if (lp->cmd_nonblocking) {
1396 if (lp->mc_reload_wait)
1397 mc32_reset_multicast_list(dev);
1399 else complete(&lp->execution_cmd);
1404 * We get interrupted once per
1405 * counter that is about to overflow.
1408 mc32_update_stats(dev);
1414 * Process the transmit and receive rings
1428 * mc32_close - user configuring the 3c527 down
1429 * @dev: 3c527 card to shut down
1431 * The 3c527 is a bus mastering device. We must be careful how we
1432 * shut it down. It may also be running shared interrupt so we have
1433 * to be sure to silence it properly
1435 * We indicate that the card is closing to the rest of the
1436 * driver. Otherwise, it is possible that the card may run out
1437 * of receive buffers and restart the transceiver while we're
1438 * trying to close it.
1440 * We abort any receive and transmits going on and then wait until
1441 * any pending exec commands have completed in other code threads.
1442 * In theory we can't get here while that is true, in practice I am
1445 * We turn off the interrupt enable for the board to be sure it can't
1446 * intefere with other devices.
1449 static int mc32_close(struct net_device *dev)
1451 struct mc32_local *lp = netdev_priv(dev);
1452 int ioaddr = dev->base_addr;
1457 lp->xceiver_desired_state = HALTED;
1458 netif_stop_queue(dev);
1461 * Send the indications on command (handy debug check)
1464 mc32_command(dev, 4, &one, 2);
1466 /* Shut down the transceiver */
1468 mc32_halt_transceiver(dev);
1470 /* Ensure we issue no more commands beyond this point */
1472 down(&lp->cmd_mutex);
1474 /* Ok the card is now stopping */
1476 regs=inb(ioaddr+HOST_CTRL);
1477 regs&=~HOST_CTRL_INTE;
1478 outb(regs, ioaddr+HOST_CTRL);
1480 mc32_flush_rx_ring(dev);
1481 mc32_flush_tx_ring(dev);
1483 mc32_update_stats(dev);
1490 * mc32_get_stats - hand back stats to network layer
1491 * @dev: The 3c527 card to handle
1493 * We've collected all the stats we can in software already. Now
1494 * it's time to update those kept on-card and return the lot.
1498 static struct net_device_stats *mc32_get_stats(struct net_device *dev)
1500 struct mc32_local *lp = netdev_priv(dev);
1502 mc32_update_stats(dev);
1503 return &lp->net_stats;
1508 * do_mc32_set_multicast_list - attempt to update multicasts
1509 * @dev: 3c527 device to load the list on
1510 * @retry: indicates this is not the first call.
1513 * Actually set or clear the multicast filter for this adaptor. The
1514 * locking issues are handled by this routine. We have to track
1515 * state as it may take multiple calls to get the command sequence
1516 * completed. We just keep trying to schedule the loads until we
1517 * manage to process them all.
1519 * num_addrs == -1 Promiscuous mode, receive all packets
1521 * num_addrs == 0 Normal mode, clear multicast list
1523 * num_addrs > 0 Multicast mode, receive normal and MC packets,
1524 * and do best-effort filtering.
1526 * See mc32_update_stats() regards setting the SAV BP bit.
1530 static void do_mc32_set_multicast_list(struct net_device *dev, int retry)
1532 struct mc32_local *lp = netdev_priv(dev);
1533 u16 filt = (1<<2); /* Save Bad Packets, for stats purposes */
1535 if (dev->flags&IFF_PROMISC)
1536 /* Enable promiscuous mode */
1538 else if((dev->flags&IFF_ALLMULTI) || dev->mc_count > 10)
1540 dev->flags|=IFF_PROMISC;
1543 else if(dev->mc_count)
1545 unsigned char block[62];
1547 struct dev_mc_list *dmc=dev->mc_list;
1552 lp->mc_list_valid = 0;
1553 if(!lp->mc_list_valid)
1556 block[0]=dev->mc_count;
1559 for(i=0;i<dev->mc_count;i++)
1561 memcpy(bp, dmc->dmi_addr, 6);
1565 if(mc32_command_nowait(dev, 2, block, 2+6*dev->mc_count)==-1)
1567 lp->mc_reload_wait = 1;
1570 lp->mc_list_valid=1;
1574 if(mc32_command_nowait(dev, 0, &filt, 2)==-1)
1576 lp->mc_reload_wait = 1;
1579 lp->mc_reload_wait = 0;
1585 * mc32_set_multicast_list - queue multicast list update
1586 * @dev: The 3c527 to use
1588 * Commence loading the multicast list. This is called when the kernel
1589 * changes the lists. It will override any pending list we are trying to
1593 static void mc32_set_multicast_list(struct net_device *dev)
1595 do_mc32_set_multicast_list(dev,0);
1600 * mc32_reset_multicast_list - reset multicast list
1601 * @dev: The 3c527 to use
1603 * Attempt the next step in loading the multicast lists. If this attempt
1604 * fails to complete then it will be scheduled and this function called
1605 * again later from elsewhere.
1608 static void mc32_reset_multicast_list(struct net_device *dev)
1610 do_mc32_set_multicast_list(dev,1);
1613 static void netdev_get_drvinfo(struct net_device *dev,
1614 struct ethtool_drvinfo *info)
1616 strcpy(info->driver, DRV_NAME);
1617 strcpy(info->version, DRV_VERSION);
1618 sprintf(info->bus_info, "MCA 0x%lx", dev->base_addr);
1621 static u32 netdev_get_msglevel(struct net_device *dev)
1626 static void netdev_set_msglevel(struct net_device *dev, u32 level)
1631 static struct ethtool_ops netdev_ethtool_ops = {
1632 .get_drvinfo = netdev_get_drvinfo,
1633 .get_msglevel = netdev_get_msglevel,
1634 .set_msglevel = netdev_set_msglevel,
1639 static struct net_device *this_device;
1642 * init_module - entry point
1644 * Probe and locate a 3c527 card. This really should probe and locate
1645 * all the 3c527 cards in the machine not just one of them. Yes you can
1646 * insmod multiple modules for now but it's a hack.
1649 int init_module(void)
1651 this_device = mc32_probe(-1);
1652 if (IS_ERR(this_device))
1653 return PTR_ERR(this_device);
1658 * cleanup_module - free resources for an unload
1660 * Unloading time. We release the MCA bus resources and the interrupt
1661 * at which point everything is ready to unload. The card must be stopped
1662 * at this point or we would not have been called. When we unload we
1663 * leave the card stopped but not totally shut down. When the card is
1664 * initialized it must be rebooted or the rings reloaded before any
1665 * transmit operations are allowed to start scribbling into memory.
1668 void cleanup_module(void)
1670 unregister_netdev(this_device);
1671 cleanup_card(this_device);
1672 free_netdev(this_device);