1 /* 3c507.c: An EtherLink16 device driver for Linux. */
2 /*
3 	Written 1993,1994 by Donald Becker.
4 
5 	Copyright 1993 United States Government as represented by the
6 	Director, National Security Agency.
7 
8 	This software may be used and distributed according to the terms
9 	of the GNU General Public License, incorporated herein by reference.
10 
11 	The author may be reached as becker@scyld.com, or C/O
12 	Scyld Computing Corporation
13 	410 Severn Ave., Suite 210
14 	Annapolis MD 21403
15 
16 
17 	Thanks go to jennings@Montrouge.SMR.slb.com ( Patrick Jennings)
18 	and jrs@world.std.com (Rick Sladkey) for testing and bugfixes.
19 	Mark Salazar <leslie@access.digex.net> made the changes for cards with
20 	only 16K packet buffers.
21 
22 	Things remaining to do:
23 	Verify that the tx and rx buffers don't have fencepost errors.
24 	Move the theory of operation and memory map documentation.
25 	The statistics need to be updated correctly.
26 */
27 
28 #define DRV_NAME		"3c507"
29 #define DRV_VERSION		"1.10a"
30 #define DRV_RELDATE		"11/17/2001"
31 
32 static const char version[] =
33 	DRV_NAME ".c:v" DRV_VERSION " " DRV_RELDATE " Donald Becker (becker@scyld.com)\n";
34 
35 /*
36   Sources:
37 	This driver wouldn't have been written with the availability of the
38 	Crynwr driver source code.	It provided a known-working implementation
39 	that filled in the gaping holes of the Intel documentation.  Three cheers
40 	for Russ Nelson.
41 
42 	Intel Microcommunications Databook, Vol. 1, 1990.  It provides just enough
43 	info that the casual reader might think that it documents the i82586 :-<.
44 */
45 
46 #include <linux/module.h>
47 #include <linux/kernel.h>
48 #include <linux/types.h>
49 #include <linux/fcntl.h>
50 #include <linux/interrupt.h>
51 #include <linux/ioport.h>
52 #include <linux/in.h>
53 #include <linux/string.h>
54 #include <linux/spinlock.h>
55 #include <linux/ethtool.h>
56 #include <linux/errno.h>
57 #include <linux/netdevice.h>
58 #include <linux/etherdevice.h>
59 #include <linux/if_ether.h>
60 #include <linux/skbuff.h>
61 #include <linux/init.h>
62 #include <linux/bitops.h>
63 
64 #include <asm/dma.h>
65 #include <asm/io.h>
66 #include <asm/system.h>
67 #include <asm/uaccess.h>
68 
69 /* use 0 for production, 1 for verification, 2..7 for debug */
70 #ifndef NET_DEBUG
71 #define NET_DEBUG 1
72 #endif
73 static unsigned int net_debug = NET_DEBUG;
74 #define debug net_debug
75 
76 
77 /*
78   			Details of the i82586.
79 
80    You'll really need the databook to understand the details of this part,
81    but the outline is that the i82586 has two separate processing units.
82    Both are started from a list of three configuration tables, of which only
83    the last, the System Control Block (SCB), is used after reset-time.  The SCB
84    has the following fields:
85 		Status word
86 		Command word
87 		Tx/Command block addr.
88 		Rx block addr.
89    The command word accepts the following controls for the Tx and Rx units:
90   */
91 
92 #define	 CUC_START	 0x0100
93 #define	 CUC_RESUME	 0x0200
94 #define	 CUC_SUSPEND 0x0300
95 #define	 RX_START	 0x0010
96 #define	 RX_RESUME	 0x0020
97 #define	 RX_SUSPEND	 0x0030
98 
99 /* The Rx unit uses a list of frame descriptors and a list of data buffer
100    descriptors.  We use full-sized (1518 byte) data buffers, so there is
101    a one-to-one pairing of frame descriptors to buffer descriptors.
102 
103    The Tx ("command") unit executes a list of commands that look like:
104 		Status word		Written by the 82586 when the command is done.
105 		Command word	Command in lower 3 bits, post-command action in upper 3
106 		Link word		The address of the next command.
107 		Parameters		(as needed).
108 
109 	Some definitions related to the Command Word are:
110  */
111 #define CMD_EOL		0x8000			/* The last command of the list, stop. */
112 #define CMD_SUSP	0x4000			/* Suspend after doing cmd. */
113 #define CMD_INTR	0x2000			/* Interrupt after doing cmd. */
114 
115 enum commands {
116 	CmdNOp = 0, CmdSASetup = 1, CmdConfigure = 2, CmdMulticastList = 3,
117 	CmdTx = 4, CmdTDR = 5, CmdDump = 6, CmdDiagnose = 7};
118 
119 /* Information that need to be kept for each board. */
120 struct net_local {
121 	int last_restart;
122 	ushort rx_head;
123 	ushort rx_tail;
124 	ushort tx_head;
125 	ushort tx_cmd_link;
126 	ushort tx_reap;
127 	ushort tx_pkts_in_ring;
128 	spinlock_t lock;
129 	void __iomem *base;
130 };
131 
132 /*
133   		Details of the EtherLink16 Implementation
134   The 3c507 is a generic shared-memory i82586 implementation.
135   The host can map 16K, 32K, 48K, or 64K of the 64K memory into
136   0x0[CD][08]0000, or all 64K into 0xF[02468]0000.
137   */
138 
139 /* Offsets from the base I/O address. */
140 #define	SA_DATA		0	/* Station address data, or 3Com signature. */
141 #define MISC_CTRL	6	/* Switch the SA_DATA banks, and bus config bits. */
142 #define RESET_IRQ	10	/* Reset the latched IRQ line. */
143 #define SIGNAL_CA	11	/* Frob the 82586 Channel Attention line. */
144 #define ROM_CONFIG	13
145 #define MEM_CONFIG	14
146 #define IRQ_CONFIG	15
147 #define EL16_IO_EXTENT 16
148 
149 /* The ID port is used at boot-time to locate the ethercard. */
150 #define ID_PORT		0x100
151 
152 /* Offsets to registers in the mailbox (SCB). */
153 #define iSCB_STATUS	0x8
154 #define iSCB_CMD		0xA
155 #define iSCB_CBL		0xC	/* Command BLock offset. */
156 #define iSCB_RFA		0xE	/* Rx Frame Area offset. */
157 
158 /*  Since the 3c507 maps the shared memory window so that the last byte is
159 	at 82586 address FFFF, the first byte is at 82586 address 0, 16K, 32K, or
160 	48K corresponding to window sizes of 64K, 48K, 32K and 16K respectively.
161 	We can account for this be setting the 'SBC Base' entry in the ISCP table
162 	below for all the 16 bit offset addresses, and also adding the 'SCB Base'
163 	value to all 24 bit physical addresses (in the SCP table and the TX and RX
164 	Buffer Descriptors).
165 					-Mark
166 	*/
167 #define SCB_BASE		((unsigned)64*1024 - (dev->mem_end - dev->mem_start))
168 
169 /*
170   What follows in 'init_words[]' is the "program" that is downloaded to the
171   82586 memory.	 It's mostly tables and command blocks, and starts at the
172   reset address 0xfffff6.  This is designed to be similar to the EtherExpress,
173   thus the unusual location of the SCB at 0x0008.
174 
175   Even with the additional "don't care" values, doing it this way takes less
176   program space than initializing the individual tables, and I feel it's much
177   cleaner.
178 
179   The databook is particularly useless for the first two structures, I had
180   to use the Crynwr driver as an example.
181 
182    The memory setup is as follows:
183    */
184 
185 #define CONFIG_CMD	0x0018
186 #define SET_SA_CMD	0x0024
187 #define SA_OFFSET	0x002A
188 #define IDLELOOP	0x30
189 #define TDR_CMD		0x38
190 #define TDR_TIME	0x3C
191 #define DUMP_CMD	0x40
192 #define DIAG_CMD	0x48
193 #define SET_MC_CMD	0x4E
194 #define DUMP_DATA	0x56	/* A 170 byte buffer for dump and Set-MC into. */
195 
196 #define TX_BUF_START	0x0100
197 #define NUM_TX_BUFS 	5
198 #define TX_BUF_SIZE 	(1518+14+20+16) /* packet+header+TBD */
199 
200 #define RX_BUF_START	0x2000
201 #define RX_BUF_SIZE 	(1518+14+18)	/* packet+header+RBD */
202 #define RX_BUF_END		(dev->mem_end - dev->mem_start)
203 
204 #define TX_TIMEOUT (HZ/20)
205 
206 /*
207   That's it: only 86 bytes to set up the beast, including every extra
208   command available.  The 170 byte buffer at DUMP_DATA is shared between the
209   Dump command (called only by the diagnostic program) and the SetMulticastList
210   command.
211 
212   To complete the memory setup you only have to write the station address at
213   SA_OFFSET and create the Tx & Rx buffer lists.
214 
215   The Tx command chain and buffer list is setup as follows:
216   A Tx command table, with the data buffer pointing to...
217   A Tx data buffer descriptor.  The packet is in a single buffer, rather than
218 	chaining together several smaller buffers.
219   A NoOp command, which initially points to itself,
220   And the packet data.
221 
222   A transmit is done by filling in the Tx command table and data buffer,
223   re-writing the NoOp command, and finally changing the offset of the last
224   command to point to the current Tx command.  When the Tx command is finished,
225   it jumps to the NoOp, when it loops until the next Tx command changes the
226   "link offset" in the NoOp.  This way the 82586 never has to go through the
227   slow restart sequence.
228 
229   The Rx buffer list is set up in the obvious ring structure.  We have enough
230   memory (and low enough interrupt latency) that we can avoid the complicated
231   Rx buffer linked lists by alway associating a full-size Rx data buffer with
232   each Rx data frame.
233 
234   I current use four transmit buffers starting at TX_BUF_START (0x0100), and
235   use the rest of memory, from RX_BUF_START to RX_BUF_END, for Rx buffers.
236 
237   */
238 
239 static unsigned short init_words[] = {
240 	/*	System Configuration Pointer (SCP). */
241 	0x0000,					/* Set bus size to 16 bits. */
242 	0,0,					/* pad words. */
243 	0x0000,0x0000,			/* ISCP phys addr, set in init_82586_mem(). */
244 
245 	/*	Intermediate System Configuration Pointer (ISCP). */
246 	0x0001,					/* Status word that's cleared when init is done. */
247 	0x0008,0,0,				/* SCB offset, (skip, skip) */
248 
249 	/* System Control Block (SCB). */
250 	0,0xf000|RX_START|CUC_START,	/* SCB status and cmd. */
251 	CONFIG_CMD,				/* Command list pointer, points to Configure. */
252 	RX_BUF_START,				/* Rx block list. */
253 	0,0,0,0,				/* Error count: CRC, align, buffer, overrun. */
254 
255 	/* 0x0018: Configure command.  Change to put MAC data with packet. */
256 	0, CmdConfigure,		/* Status, command.		*/
257 	SET_SA_CMD,				/* Next command is Set Station Addr. */
258 	0x0804,					/* "4" bytes of config data, 8 byte FIFO. */
259 	0x2e40,					/* Magic values, including MAC data location. */
260 	0,						/* Unused pad word. */
261 
262 	/* 0x0024: Setup station address command. */
263 	0, CmdSASetup,
264 	SET_MC_CMD,				/* Next command. */
265 	0xaa00,0xb000,0x0bad,	/* Station address (to be filled in) */
266 
267 	/* 0x0030: NOP, looping back to itself.	 Point to first Tx buffer to Tx. */
268 	0, CmdNOp, IDLELOOP, 0 /* pad */,
269 
270 	/* 0x0038: A unused Time-Domain Reflectometer command. */
271 	0, CmdTDR, IDLELOOP, 0,
272 
273 	/* 0x0040: An unused Dump State command. */
274 	0, CmdDump, IDLELOOP, DUMP_DATA,
275 
276 	/* 0x0048: An unused Diagnose command. */
277 	0, CmdDiagnose, IDLELOOP,
278 
279 	/* 0x004E: An empty set-multicast-list command. */
280 	0, CmdMulticastList, IDLELOOP, 0,
281 };
282 
283 /* Index to functions, as function prototypes. */
284 
285 static int	el16_probe1(struct net_device *dev, int ioaddr);
286 static int	el16_open(struct net_device *dev);
287 static netdev_tx_t el16_send_packet(struct sk_buff *skb,
288 				    struct net_device *dev);
289 static irqreturn_t el16_interrupt(int irq, void *dev_id);
290 static void el16_rx(struct net_device *dev);
291 static int	el16_close(struct net_device *dev);
292 static void el16_tx_timeout (struct net_device *dev);
293 
294 static void hardware_send_packet(struct net_device *dev, void *buf, short length, short pad);
295 static void init_82586_mem(struct net_device *dev);
296 static const struct ethtool_ops netdev_ethtool_ops;
297 static void init_rx_bufs(struct net_device *);
298 
299 static int io = 0x300;
300 static int irq;
301 static int mem_start;
302 
303 
304 /* Check for a network adaptor of this type, and return '0' iff one exists.
305 	If dev->base_addr == 0, probe all likely locations.
306 	If dev->base_addr == 1, always return failure.
307 	If dev->base_addr == 2, (detachable devices only) allocate space for the
308 	device and return success.
309 	*/
310 
el16_probe(int unit)311 struct net_device * __init el16_probe(int unit)
312 {
313 	struct net_device *dev = alloc_etherdev(sizeof(struct net_local));
314 	static const unsigned ports[] = { 0x300, 0x320, 0x340, 0x280, 0};
315 	const unsigned *port;
316 	int err = -ENODEV;
317 
318 	if (!dev)
319 		return ERR_PTR(-ENODEV);
320 
321 	if (unit >= 0) {
322 		sprintf(dev->name, "eth%d", unit);
323 		netdev_boot_setup_check(dev);
324 		io = dev->base_addr;
325 		irq = dev->irq;
326 		mem_start = dev->mem_start & 15;
327 	}
328 
329 	if (io > 0x1ff) 	/* Check a single specified location. */
330 		err = el16_probe1(dev, io);
331 	else if (io != 0)
332 		err = -ENXIO;		/* Don't probe at all. */
333 	else {
334 		for (port = ports; *port; port++) {
335 			err = el16_probe1(dev, *port);
336 			if (!err)
337 				break;
338 		}
339 	}
340 
341 	if (err)
342 		goto out;
343 	err = register_netdev(dev);
344 	if (err)
345 		goto out1;
346 	return dev;
347 out1:
348 	free_irq(dev->irq, dev);
349 	iounmap(((struct net_local *)netdev_priv(dev))->base);
350 	release_region(dev->base_addr, EL16_IO_EXTENT);
351 out:
352 	free_netdev(dev);
353 	return ERR_PTR(err);
354 }
355 
356 static const struct net_device_ops netdev_ops = {
357 	.ndo_open		= el16_open,
358 	.ndo_stop		= el16_close,
359 	.ndo_start_xmit 	= el16_send_packet,
360 	.ndo_tx_timeout 	= el16_tx_timeout,
361 	.ndo_change_mtu		= eth_change_mtu,
362 	.ndo_set_mac_address 	= eth_mac_addr,
363 	.ndo_validate_addr	= eth_validate_addr,
364 };
365 
el16_probe1(struct net_device * dev,int ioaddr)366 static int __init el16_probe1(struct net_device *dev, int ioaddr)
367 {
368 	static unsigned char init_ID_done;
369 	int i, irq, irqval, retval;
370 	struct net_local *lp;
371 
372 	if (init_ID_done == 0) {
373 		ushort lrs_state = 0xff;
374 		/* Send the ID sequence to the ID_PORT to enable the board(s). */
375 		outb(0x00, ID_PORT);
376 		for(i = 0; i < 255; i++) {
377 			outb(lrs_state, ID_PORT);
378 			lrs_state <<= 1;
379 			if (lrs_state & 0x100)
380 				lrs_state ^= 0xe7;
381 		}
382 		outb(0x00, ID_PORT);
383 		init_ID_done = 1;
384 	}
385 
386 	if (!request_region(ioaddr, EL16_IO_EXTENT, DRV_NAME))
387 		return -ENODEV;
388 
389 	if ((inb(ioaddr) != '*') || (inb(ioaddr + 1) != '3') ||
390 	    (inb(ioaddr + 2) != 'C') || (inb(ioaddr + 3) != 'O')) {
391 		retval = -ENODEV;
392 		goto out;
393 	}
394 
395 	pr_info("%s: 3c507 at %#x,", dev->name, ioaddr);
396 
397 	/* We should make a few more checks here, like the first three octets of
398 	   the S.A. for the manufacturer's code. */
399 
400 	irq = inb(ioaddr + IRQ_CONFIG) & 0x0f;
401 
402 	irqval = request_irq(irq, el16_interrupt, 0, DRV_NAME, dev);
403 	if (irqval) {
404 		pr_cont("\n");
405 		pr_err("3c507: unable to get IRQ %d (irqval=%d).\n", irq, irqval);
406 		retval = -EAGAIN;
407 		goto out;
408 	}
409 
410 	/* We've committed to using the board, and can start filling in *dev. */
411 	dev->base_addr = ioaddr;
412 
413 	outb(0x01, ioaddr + MISC_CTRL);
414 	for (i = 0; i < 6; i++)
415 		dev->dev_addr[i] = inb(ioaddr + i);
416 	pr_cont(" %pM", dev->dev_addr);
417 
418 	if (mem_start)
419 		net_debug = mem_start & 7;
420 
421 #ifdef MEM_BASE
422 	dev->mem_start = MEM_BASE;
423 	dev->mem_end = dev->mem_start + 0x10000;
424 #else
425 	{
426 		int base;
427 		int size;
428 		char mem_config = inb(ioaddr + MEM_CONFIG);
429 		if (mem_config & 0x20) {
430 			size = 64*1024;
431 			base = 0xf00000 + (mem_config & 0x08 ? 0x080000
432 							   : ((mem_config & 3) << 17));
433 		} else {
434 			size = ((mem_config & 3) + 1) << 14;
435 			base = 0x0c0000 + ( (mem_config & 0x18) << 12);
436 		}
437 		dev->mem_start = base;
438 		dev->mem_end = base + size;
439 	}
440 #endif
441 
442 	dev->if_port = (inb(ioaddr + ROM_CONFIG) & 0x80) ? 1 : 0;
443 	dev->irq = inb(ioaddr + IRQ_CONFIG) & 0x0f;
444 
445 	pr_cont(", IRQ %d, %sternal xcvr, memory %#lx-%#lx.\n", dev->irq,
446 		   dev->if_port ? "ex" : "in", dev->mem_start, dev->mem_end-1);
447 
448 	if (net_debug)
449 		pr_debug("%s", version);
450 
451 	lp = netdev_priv(dev);
452 	spin_lock_init(&lp->lock);
453 	lp->base = ioremap(dev->mem_start, RX_BUF_END);
454 	if (!lp->base) {
455 		pr_err("3c507: unable to remap memory\n");
456 		retval = -EAGAIN;
457 		goto out1;
458 	}
459 
460 	dev->netdev_ops = &netdev_ops;
461 	dev->watchdog_timeo = TX_TIMEOUT;
462 	dev->ethtool_ops = &netdev_ethtool_ops;
463  	dev->flags &= ~IFF_MULTICAST;	/* Multicast doesn't work */
464 	return 0;
465 out1:
466 	free_irq(dev->irq, dev);
467 out:
468 	release_region(ioaddr, EL16_IO_EXTENT);
469 	return retval;
470 }
471 
el16_open(struct net_device * dev)472 static int el16_open(struct net_device *dev)
473 {
474 	/* Initialize the 82586 memory and start it. */
475 	init_82586_mem(dev);
476 
477 	netif_start_queue(dev);
478 	return 0;
479 }
480 
481 
el16_tx_timeout(struct net_device * dev)482 static void el16_tx_timeout (struct net_device *dev)
483 {
484 	struct net_local *lp = netdev_priv(dev);
485 	int ioaddr = dev->base_addr;
486 	void __iomem *shmem = lp->base;
487 
488 	if (net_debug > 1)
489 		pr_debug("%s: transmit timed out, %s?  ", dev->name,
490 			readw(shmem + iSCB_STATUS) & 0x8000 ? "IRQ conflict" :
491 			"network cable problem");
492 	/* Try to restart the adaptor. */
493 	if (lp->last_restart == dev->stats.tx_packets) {
494 		if (net_debug > 1)
495 			pr_cont("Resetting board.\n");
496 		/* Completely reset the adaptor. */
497 		init_82586_mem (dev);
498 		lp->tx_pkts_in_ring = 0;
499 	} else {
500 		/* Issue the channel attention signal and hope it "gets better". */
501 		if (net_debug > 1)
502 			pr_cont("Kicking board.\n");
503 		writew(0xf000 | CUC_START | RX_START, shmem + iSCB_CMD);
504 		outb (0, ioaddr + SIGNAL_CA);	/* Issue channel-attn. */
505 		lp->last_restart = dev->stats.tx_packets;
506 	}
507 	dev->trans_start = jiffies; /* prevent tx timeout */
508 	netif_wake_queue (dev);
509 }
510 
511 
el16_send_packet(struct sk_buff * skb,struct net_device * dev)512 static netdev_tx_t el16_send_packet (struct sk_buff *skb,
513 				     struct net_device *dev)
514 {
515 	struct net_local *lp = netdev_priv(dev);
516 	int ioaddr = dev->base_addr;
517 	unsigned long flags;
518 	short length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN;
519 	unsigned char *buf = skb->data;
520 
521 	netif_stop_queue (dev);
522 
523 	spin_lock_irqsave (&lp->lock, flags);
524 
525 	dev->stats.tx_bytes += length;
526 	/* Disable the 82586's input to the interrupt line. */
527 	outb (0x80, ioaddr + MISC_CTRL);
528 
529 	hardware_send_packet (dev, buf, skb->len, length - skb->len);
530 
531 	/* Enable the 82586 interrupt input. */
532 	outb (0x84, ioaddr + MISC_CTRL);
533 
534 	spin_unlock_irqrestore (&lp->lock, flags);
535 
536 	dev_kfree_skb (skb);
537 
538 	/* You might need to clean up and record Tx statistics here. */
539 
540 	return NETDEV_TX_OK;
541 }
542 
543 /*	The typical workload of the driver:
544 	Handle the network interface interrupts. */
el16_interrupt(int irq,void * dev_id)545 static irqreturn_t el16_interrupt(int irq, void *dev_id)
546 {
547 	struct net_device *dev = dev_id;
548 	struct net_local *lp;
549 	int ioaddr, status, boguscount = 0;
550 	ushort ack_cmd = 0;
551 	void __iomem *shmem;
552 
553 	if (dev == NULL) {
554 		pr_err("net_interrupt(): irq %d for unknown device.\n", irq);
555 		return IRQ_NONE;
556 	}
557 
558 	ioaddr = dev->base_addr;
559 	lp = netdev_priv(dev);
560 	shmem = lp->base;
561 
562 	spin_lock(&lp->lock);
563 
564 	status = readw(shmem+iSCB_STATUS);
565 
566 	if (net_debug > 4) {
567 		pr_debug("%s: 3c507 interrupt, status %4.4x.\n", dev->name, status);
568 	}
569 
570 	/* Disable the 82586's input to the interrupt line. */
571 	outb(0x80, ioaddr + MISC_CTRL);
572 
573 	/* Reap the Tx packet buffers. */
574 	while (lp->tx_pkts_in_ring) {
575 	  unsigned short tx_status = readw(shmem+lp->tx_reap);
576 	  if (!(tx_status & 0x8000)) {
577 		if (net_debug > 5)
578 			pr_debug("Tx command incomplete (%#x).\n", lp->tx_reap);
579 		break;
580 	  }
581 	  /* Tx unsuccessful or some interesting status bit set. */
582 	  if (!(tx_status & 0x2000) || (tx_status & 0x0f3f)) {
583 		dev->stats.tx_errors++;
584 		if (tx_status & 0x0600)  dev->stats.tx_carrier_errors++;
585 		if (tx_status & 0x0100)  dev->stats.tx_fifo_errors++;
586 		if (!(tx_status & 0x0040))  dev->stats.tx_heartbeat_errors++;
587 		if (tx_status & 0x0020)  dev->stats.tx_aborted_errors++;
588 		dev->stats.collisions += tx_status & 0xf;
589 	  }
590 	  dev->stats.tx_packets++;
591 	  if (net_debug > 5)
592 		  pr_debug("Reaped %x, Tx status %04x.\n" , lp->tx_reap, tx_status);
593 	  lp->tx_reap += TX_BUF_SIZE;
594 	  if (lp->tx_reap > RX_BUF_START - TX_BUF_SIZE)
595 		lp->tx_reap = TX_BUF_START;
596 
597 	  lp->tx_pkts_in_ring--;
598 	  /* There is always more space in the Tx ring buffer now. */
599 	  netif_wake_queue(dev);
600 
601 	  if (++boguscount > 10)
602 		break;
603 	}
604 
605 	if (status & 0x4000) { /* Packet received. */
606 		if (net_debug > 5)
607 			pr_debug("Received packet, rx_head %04x.\n", lp->rx_head);
608 		el16_rx(dev);
609 	}
610 
611 	/* Acknowledge the interrupt sources. */
612 	ack_cmd = status & 0xf000;
613 
614 	if ((status & 0x0700) != 0x0200 && netif_running(dev)) {
615 		if (net_debug)
616 			pr_debug("%s: Command unit stopped, status %04x, restarting.\n",
617 				   dev->name, status);
618 		/* If this ever occurs we should really re-write the idle loop, reset
619 		   the Tx list, and do a complete restart of the command unit.
620 		   For now we rely on the Tx timeout if the resume doesn't work. */
621 		ack_cmd |= CUC_RESUME;
622 	}
623 
624 	if ((status & 0x0070) != 0x0040 && netif_running(dev)) {
625 		/* The Rx unit is not ready, it must be hung.  Restart the receiver by
626 		   initializing the rx buffers, and issuing an Rx start command. */
627 		if (net_debug)
628 			pr_debug("%s: Rx unit stopped, status %04x, restarting.\n",
629 				   dev->name, status);
630 		init_rx_bufs(dev);
631 		writew(RX_BUF_START,shmem+iSCB_RFA);
632 		ack_cmd |= RX_START;
633 	}
634 
635 	writew(ack_cmd,shmem+iSCB_CMD);
636 	outb(0, ioaddr + SIGNAL_CA);			/* Issue channel-attn. */
637 
638 	/* Clear the latched interrupt. */
639 	outb(0, ioaddr + RESET_IRQ);
640 
641 	/* Enable the 82586's interrupt input. */
642 	outb(0x84, ioaddr + MISC_CTRL);
643 	spin_unlock(&lp->lock);
644 	return IRQ_HANDLED;
645 }
646 
el16_close(struct net_device * dev)647 static int el16_close(struct net_device *dev)
648 {
649 	struct net_local *lp = netdev_priv(dev);
650 	int ioaddr = dev->base_addr;
651 	void __iomem *shmem = lp->base;
652 
653 	netif_stop_queue(dev);
654 
655 	/* Flush the Tx and disable Rx. */
656 	writew(RX_SUSPEND | CUC_SUSPEND,shmem+iSCB_CMD);
657 	outb(0, ioaddr + SIGNAL_CA);
658 
659 	/* Disable the 82586's input to the interrupt line. */
660 	outb(0x80, ioaddr + MISC_CTRL);
661 
662 	/* We always physically use the IRQ line, so we don't do free_irq(). */
663 
664 	/* Update the statistics here. */
665 
666 	return 0;
667 }
668 
669 /* Initialize the Rx-block list. */
init_rx_bufs(struct net_device * dev)670 static void init_rx_bufs(struct net_device *dev)
671 {
672 	struct net_local *lp = netdev_priv(dev);
673 	void __iomem *write_ptr;
674 	unsigned short SCB_base = SCB_BASE;
675 
676 	int cur_rxbuf = lp->rx_head = RX_BUF_START;
677 
678 	/* Initialize each Rx frame + data buffer. */
679 	do {	/* While there is room for one more. */
680 
681 		write_ptr = lp->base + cur_rxbuf;
682 
683 		writew(0x0000,write_ptr);			/* Status */
684 		writew(0x0000,write_ptr+=2);			/* Command */
685 		writew(cur_rxbuf + RX_BUF_SIZE,write_ptr+=2);	/* Link */
686 		writew(cur_rxbuf + 22,write_ptr+=2);		/* Buffer offset */
687 		writew(0x0000,write_ptr+=2);			/* Pad for dest addr. */
688 		writew(0x0000,write_ptr+=2);
689 		writew(0x0000,write_ptr+=2);
690 		writew(0x0000,write_ptr+=2);			/* Pad for source addr. */
691 		writew(0x0000,write_ptr+=2);
692 		writew(0x0000,write_ptr+=2);
693 		writew(0x0000,write_ptr+=2);			/* Pad for protocol. */
694 
695 		writew(0x0000,write_ptr+=2);			/* Buffer: Actual count */
696 		writew(-1,write_ptr+=2);			/* Buffer: Next (none). */
697 		writew(cur_rxbuf + 0x20 + SCB_base,write_ptr+=2);/* Buffer: Address low */
698 		writew(0x0000,write_ptr+=2);
699 		/* Finally, the number of bytes in the buffer. */
700 		writew(0x8000 + RX_BUF_SIZE-0x20,write_ptr+=2);
701 
702 		lp->rx_tail = cur_rxbuf;
703 		cur_rxbuf += RX_BUF_SIZE;
704 	} while (cur_rxbuf <= RX_BUF_END - RX_BUF_SIZE);
705 
706 	/* Terminate the list by setting the EOL bit, and wrap the pointer to make
707 	   the list a ring. */
708 	write_ptr = lp->base + lp->rx_tail + 2;
709 	writew(0xC000,write_ptr);				/* Command, mark as last. */
710 	writew(lp->rx_head,write_ptr+2);			/* Link */
711 }
712 
init_82586_mem(struct net_device * dev)713 static void init_82586_mem(struct net_device *dev)
714 {
715 	struct net_local *lp = netdev_priv(dev);
716 	short ioaddr = dev->base_addr;
717 	void __iomem *shmem = lp->base;
718 
719 	/* Enable loopback to protect the wire while starting up,
720 	   and hold the 586 in reset during the memory initialization. */
721 	outb(0x20, ioaddr + MISC_CTRL);
722 
723 	/* Fix the ISCP address and base. */
724 	init_words[3] = SCB_BASE;
725 	init_words[7] = SCB_BASE;
726 
727 	/* Write the words at 0xfff6 (address-aliased to 0xfffff6). */
728 	memcpy_toio(lp->base + RX_BUF_END - 10, init_words, 10);
729 
730 	/* Write the words at 0x0000. */
731 	memcpy_toio(lp->base, init_words + 5, sizeof(init_words) - 10);
732 
733 	/* Fill in the station address. */
734 	memcpy_toio(lp->base+SA_OFFSET, dev->dev_addr, ETH_ALEN);
735 
736 	/* The Tx-block list is written as needed.  We just set up the values. */
737 	lp->tx_cmd_link = IDLELOOP + 4;
738 	lp->tx_head = lp->tx_reap = TX_BUF_START;
739 
740 	init_rx_bufs(dev);
741 
742 	/* Start the 586 by releasing the reset line, but leave loopback. */
743 	outb(0xA0, ioaddr + MISC_CTRL);
744 
745 	/* This was time consuming to track down: you need to give two channel
746 	   attention signals to reliably start up the i82586. */
747 	outb(0, ioaddr + SIGNAL_CA);
748 
749 	{
750 		int boguscnt = 50;
751 		while (readw(shmem+iSCB_STATUS) == 0)
752 			if (--boguscnt == 0) {
753 				pr_warning("%s: i82586 initialization timed out with status %04x, cmd %04x.\n",
754 					dev->name, readw(shmem+iSCB_STATUS), readw(shmem+iSCB_CMD));
755 				break;
756 			}
757 		/* Issue channel-attn -- the 82586 won't start. */
758 		outb(0, ioaddr + SIGNAL_CA);
759 	}
760 
761 	/* Disable loopback and enable interrupts. */
762 	outb(0x84, ioaddr + MISC_CTRL);
763 	if (net_debug > 4)
764 		pr_debug("%s: Initialized 82586, status %04x.\n", dev->name,
765 			   readw(shmem+iSCB_STATUS));
766 }
767 
hardware_send_packet(struct net_device * dev,void * buf,short length,short pad)768 static void hardware_send_packet(struct net_device *dev, void *buf, short length, short pad)
769 {
770 	struct net_local *lp = netdev_priv(dev);
771 	short ioaddr = dev->base_addr;
772 	ushort tx_block = lp->tx_head;
773 	void __iomem *write_ptr = lp->base + tx_block;
774 	static char padding[ETH_ZLEN];
775 
776 	/* Set the write pointer to the Tx block, and put out the header. */
777 	writew(0x0000,write_ptr);			/* Tx status */
778 	writew(CMD_INTR|CmdTx,write_ptr+=2);		/* Tx command */
779 	writew(tx_block+16,write_ptr+=2);		/* Next command is a NoOp. */
780 	writew(tx_block+8,write_ptr+=2);			/* Data Buffer offset. */
781 
782 	/* Output the data buffer descriptor. */
783 	writew((pad + length) | 0x8000,write_ptr+=2);		/* Byte count parameter. */
784 	writew(-1,write_ptr+=2);			/* No next data buffer. */
785 	writew(tx_block+22+SCB_BASE,write_ptr+=2);	/* Buffer follows the NoOp command. */
786 	writew(0x0000,write_ptr+=2);			/* Buffer address high bits (always zero). */
787 
788 	/* Output the Loop-back NoOp command. */
789 	writew(0x0000,write_ptr+=2);			/* Tx status */
790 	writew(CmdNOp,write_ptr+=2);			/* Tx command */
791 	writew(tx_block+16,write_ptr+=2);		/* Next is myself. */
792 
793 	/* Output the packet at the write pointer. */
794 	memcpy_toio(write_ptr+2, buf, length);
795 	if (pad)
796 		memcpy_toio(write_ptr+length+2, padding, pad);
797 
798 	/* Set the old command link pointing to this send packet. */
799 	writew(tx_block,lp->base + lp->tx_cmd_link);
800 	lp->tx_cmd_link = tx_block + 20;
801 
802 	/* Set the next free tx region. */
803 	lp->tx_head = tx_block + TX_BUF_SIZE;
804 	if (lp->tx_head > RX_BUF_START - TX_BUF_SIZE)
805 		lp->tx_head = TX_BUF_START;
806 
807 	if (net_debug > 4) {
808 		pr_debug("%s: 3c507 @%x send length = %d, tx_block %3x, next %3x.\n",
809 			   dev->name, ioaddr, length, tx_block, lp->tx_head);
810 	}
811 
812 	/* Grimly block further packets if there has been insufficient reaping. */
813 	if (++lp->tx_pkts_in_ring < NUM_TX_BUFS)
814 		netif_wake_queue(dev);
815 }
816 
el16_rx(struct net_device * dev)817 static void el16_rx(struct net_device *dev)
818 {
819 	struct net_local *lp = netdev_priv(dev);
820 	void __iomem *shmem = lp->base;
821 	ushort rx_head = lp->rx_head;
822 	ushort rx_tail = lp->rx_tail;
823 	ushort boguscount = 10;
824 	short frame_status;
825 
826 	while ((frame_status = readw(shmem+rx_head)) < 0) {   /* Command complete */
827 		void __iomem *read_frame = lp->base + rx_head;
828 		ushort rfd_cmd = readw(read_frame+2);
829 		ushort next_rx_frame = readw(read_frame+4);
830 		ushort data_buffer_addr = readw(read_frame+6);
831 		void __iomem *data_frame = lp->base + data_buffer_addr;
832 		ushort pkt_len = readw(data_frame);
833 
834 		if (rfd_cmd != 0 || data_buffer_addr != rx_head + 22 ||
835 		    (pkt_len & 0xC000) != 0xC000) {
836 			pr_err("%s: Rx frame at %#x corrupted, "
837 			       "status %04x cmd %04x next %04x "
838 			       "data-buf @%04x %04x.\n",
839 			       dev->name, rx_head, frame_status, rfd_cmd,
840 			       next_rx_frame, data_buffer_addr, pkt_len);
841 		} else if ((frame_status & 0x2000) == 0) {
842 			/* Frame Rxed, but with error. */
843 			dev->stats.rx_errors++;
844 			if (frame_status & 0x0800) dev->stats.rx_crc_errors++;
845 			if (frame_status & 0x0400) dev->stats.rx_frame_errors++;
846 			if (frame_status & 0x0200) dev->stats.rx_fifo_errors++;
847 			if (frame_status & 0x0100) dev->stats.rx_over_errors++;
848 			if (frame_status & 0x0080) dev->stats.rx_length_errors++;
849 		} else {
850 			/* Malloc up new buffer. */
851 			struct sk_buff *skb;
852 
853 			pkt_len &= 0x3fff;
854 			skb = dev_alloc_skb(pkt_len+2);
855 			if (skb == NULL) {
856 				pr_err("%s: Memory squeeze, dropping packet.\n",
857 				       dev->name);
858 				dev->stats.rx_dropped++;
859 				break;
860 			}
861 
862 			skb_reserve(skb,2);
863 
864 			/* 'skb->data' points to the start of sk_buff data area. */
865 			memcpy_fromio(skb_put(skb,pkt_len), data_frame + 10, pkt_len);
866 
867 			skb->protocol=eth_type_trans(skb,dev);
868 			netif_rx(skb);
869 			dev->stats.rx_packets++;
870 			dev->stats.rx_bytes += pkt_len;
871 		}
872 
873 		/* Clear the status word and set End-of-List on the rx frame. */
874 		writew(0,read_frame);
875 		writew(0xC000,read_frame+2);
876 		/* Clear the end-of-list on the prev. RFD. */
877 		writew(0x0000,lp->base + rx_tail + 2);
878 
879 		rx_tail = rx_head;
880 		rx_head = next_rx_frame;
881 		if (--boguscount == 0)
882 			break;
883 	}
884 
885 	lp->rx_head = rx_head;
886 	lp->rx_tail = rx_tail;
887 }
888 
netdev_get_drvinfo(struct net_device * dev,struct ethtool_drvinfo * info)889 static void netdev_get_drvinfo(struct net_device *dev,
890 			       struct ethtool_drvinfo *info)
891 {
892 	strcpy(info->driver, DRV_NAME);
893 	strcpy(info->version, DRV_VERSION);
894 	sprintf(info->bus_info, "ISA 0x%lx", dev->base_addr);
895 }
896 
netdev_get_msglevel(struct net_device * dev)897 static u32 netdev_get_msglevel(struct net_device *dev)
898 {
899 	return debug;
900 }
901 
netdev_set_msglevel(struct net_device * dev,u32 level)902 static void netdev_set_msglevel(struct net_device *dev, u32 level)
903 {
904 	debug = level;
905 }
906 
907 static const struct ethtool_ops netdev_ethtool_ops = {
908 	.get_drvinfo		= netdev_get_drvinfo,
909 	.get_msglevel		= netdev_get_msglevel,
910 	.set_msglevel		= netdev_set_msglevel,
911 };
912 
913 #ifdef MODULE
914 static struct net_device *dev_3c507;
915 module_param(io, int, 0);
916 module_param(irq, int, 0);
917 MODULE_PARM_DESC(io, "EtherLink16 I/O base address");
918 MODULE_PARM_DESC(irq, "(ignored)");
919 
init_module(void)920 int __init init_module(void)
921 {
922 	if (io == 0)
923 		pr_notice("3c507: You should not use auto-probing with insmod!\n");
924 	dev_3c507 = el16_probe(-1);
925 	return IS_ERR(dev_3c507) ? PTR_ERR(dev_3c507) : 0;
926 }
927 
928 void __exit
cleanup_module(void)929 cleanup_module(void)
930 {
931 	struct net_device *dev = dev_3c507;
932 	unregister_netdev(dev);
933 	free_irq(dev->irq, dev);
934 	iounmap(((struct net_local *)netdev_priv(dev))->base);
935 	release_region(dev->base_addr, EL16_IO_EXTENT);
936 	free_netdev(dev);
937 }
938 #endif /* MODULE */
939 MODULE_LICENSE("GPL");
940