1 /* epic100.c: A SMC 83c170 EPIC/100 Fast Ethernet driver for Linux. */
2 /*
3 	Written/copyright 1997-2001 by Donald Becker.
4 
5 	This software may be used and distributed according to the terms of
6 	the GNU General Public License (GPL), incorporated herein by reference.
7 	Drivers based on or derived from this code fall under the GPL and must
8 	retain the authorship, copyright and license notice.  This file is not
9 	a complete program and may only be used when the entire operating
10 	system is licensed under the GPL.
11 
12 	This driver is for the SMC83c170/175 "EPIC" series, as used on the
13 	SMC EtherPower II 9432 PCI adapter, and several CardBus cards.
14 
15 	The author may be reached as becker@scyld.com, or C/O
16 	Scyld Computing Corporation
17 	410 Severn Ave., Suite 210
18 	Annapolis MD 21403
19 
20 	Information and updates available at
21 	http://www.scyld.com/network/epic100.html
22 	[this link no longer provides anything useful -jgarzik]
23 
24 	---------------------------------------------------------------------
25 
26 */
27 
28 #define DRV_NAME        "epic100"
29 #define DRV_VERSION     "2.1"
30 #define DRV_RELDATE     "Sept 11, 2006"
31 
32 /* The user-configurable values.
33    These may be modified when a driver module is loaded.*/
34 
35 static int debug = 1;			/* 1 normal messages, 0 quiet .. 7 verbose. */
36 
37 /* Used to pass the full-duplex flag, etc. */
38 #define MAX_UNITS 8		/* More are supported, limit only on options */
39 static int options[MAX_UNITS] = {-1, -1, -1, -1, -1, -1, -1, -1};
40 static int full_duplex[MAX_UNITS] = {-1, -1, -1, -1, -1, -1, -1, -1};
41 
42 /* Set the copy breakpoint for the copy-only-tiny-frames scheme.
43    Setting to > 1518 effectively disables this feature. */
44 static int rx_copybreak;
45 
46 /* Operational parameters that are set at compile time. */
47 
48 /* Keep the ring sizes a power of two for operational efficiency.
49    The compiler will convert <unsigned>'%'<2^N> into a bit mask.
50    Making the Tx ring too large decreases the effectiveness of channel
51    bonding and packet priority.
52    There are no ill effects from too-large receive rings. */
53 #define TX_RING_SIZE	256
54 #define TX_QUEUE_LEN	240		/* Limit ring entries actually used.  */
55 #define RX_RING_SIZE	256
56 #define TX_TOTAL_SIZE	TX_RING_SIZE*sizeof(struct epic_tx_desc)
57 #define RX_TOTAL_SIZE	RX_RING_SIZE*sizeof(struct epic_rx_desc)
58 
59 /* Operational parameters that usually are not changed. */
60 /* Time in jiffies before concluding the transmitter is hung. */
61 #define TX_TIMEOUT  (2*HZ)
62 
63 #define PKT_BUF_SZ		1536			/* Size of each temporary Rx buffer.*/
64 
65 /* Bytes transferred to chip before transmission starts. */
66 /* Initial threshold, increased on underflow, rounded down to 4 byte units. */
67 #define TX_FIFO_THRESH 256
68 #define RX_FIFO_THRESH 1		/* 0-3, 0==32, 64,96, or 3==128 bytes  */
69 
70 #include <linux/module.h>
71 #include <linux/kernel.h>
72 #include <linux/string.h>
73 #include <linux/timer.h>
74 #include <linux/errno.h>
75 #include <linux/ioport.h>
76 #include <linux/interrupt.h>
77 #include <linux/pci.h>
78 #include <linux/delay.h>
79 #include <linux/netdevice.h>
80 #include <linux/etherdevice.h>
81 #include <linux/skbuff.h>
82 #include <linux/init.h>
83 #include <linux/spinlock.h>
84 #include <linux/ethtool.h>
85 #include <linux/mii.h>
86 #include <linux/crc32.h>
87 #include <linux/bitops.h>
88 #include <asm/io.h>
89 #include <asm/uaccess.h>
90 #include <asm/byteorder.h>
91 
92 /* These identify the driver base version and may not be removed. */
93 static char version[] =
94 DRV_NAME ".c:v1.11 1/7/2001 Written by Donald Becker <becker@scyld.com>";
95 static char version2[] =
96 "  (unofficial 2.4.x kernel port, version " DRV_VERSION ", " DRV_RELDATE ")";
97 
98 MODULE_AUTHOR("Donald Becker <becker@scyld.com>");
99 MODULE_DESCRIPTION("SMC 83c170 EPIC series Ethernet driver");
100 MODULE_LICENSE("GPL");
101 
102 module_param(debug, int, 0);
103 module_param(rx_copybreak, int, 0);
104 module_param_array(options, int, NULL, 0);
105 module_param_array(full_duplex, int, NULL, 0);
106 MODULE_PARM_DESC(debug, "EPIC/100 debug level (0-5)");
107 MODULE_PARM_DESC(options, "EPIC/100: Bits 0-3: media type, bit 4: full duplex");
108 MODULE_PARM_DESC(rx_copybreak, "EPIC/100 copy breakpoint for copy-only-tiny-frames");
109 MODULE_PARM_DESC(full_duplex, "EPIC/100 full duplex setting(s) (1)");
110 
111 /*
112 				Theory of Operation
113 
114 I. Board Compatibility
115 
116 This device driver is designed for the SMC "EPIC/100", the SMC
117 single-chip Ethernet controllers for PCI.  This chip is used on
118 the SMC EtherPower II boards.
119 
120 II. Board-specific settings
121 
122 PCI bus devices are configured by the system at boot time, so no jumpers
123 need to be set on the board.  The system BIOS will assign the
124 PCI INTA signal to a (preferably otherwise unused) system IRQ line.
125 Note: Kernel versions earlier than 1.3.73 do not support shared PCI
126 interrupt lines.
127 
128 III. Driver operation
129 
130 IIIa. Ring buffers
131 
132 IVb. References
133 
134 http://www.smsc.com/media/Downloads_Public/discontinued/83c171.pdf
135 http://www.smsc.com/media/Downloads_Public/discontinued/83c175.pdf
136 http://scyld.com/expert/NWay.html
137 http://www.national.com/pf/DP/DP83840A.html
138 
139 IVc. Errata
140 
141 */
142 
143 
144 enum chip_capability_flags { MII_PWRDWN=1, TYPE2_INTR=2, NO_MII=4 };
145 
146 #define EPIC_TOTAL_SIZE 0x100
147 #define USE_IO_OPS 1
148 
149 #ifdef USE_IO_OPS
150 #define EPIC_BAR	0
151 #else
152 #define EPIC_BAR	1
153 #endif
154 
155 typedef enum {
156 	SMSC_83C170_0,
157 	SMSC_83C170,
158 	SMSC_83C175,
159 } chip_t;
160 
161 
162 struct epic_chip_info {
163 	const char *name;
164         int drv_flags;                          /* Driver use, intended as capability flags. */
165 };
166 
167 
168 /* indexed by chip_t */
169 static const struct epic_chip_info pci_id_tbl[] = {
170 	{ "SMSC EPIC/100 83c170",	TYPE2_INTR | NO_MII | MII_PWRDWN },
171 	{ "SMSC EPIC/100 83c170",	TYPE2_INTR },
172 	{ "SMSC EPIC/C 83c175",		TYPE2_INTR | MII_PWRDWN },
173 };
174 
175 
176 static const struct pci_device_id epic_pci_tbl[] = {
177 	{ 0x10B8, 0x0005, 0x1092, 0x0AB4, 0, 0, SMSC_83C170_0 },
178 	{ 0x10B8, 0x0005, PCI_ANY_ID, PCI_ANY_ID, 0, 0, SMSC_83C170 },
179 	{ 0x10B8, 0x0006, PCI_ANY_ID, PCI_ANY_ID,
180 	  PCI_CLASS_NETWORK_ETHERNET << 8, 0xffff00, SMSC_83C175 },
181 	{ 0,}
182 };
183 MODULE_DEVICE_TABLE (pci, epic_pci_tbl);
184 
185 #define ew16(reg, val)	iowrite16(val, ioaddr + (reg))
186 #define ew32(reg, val)	iowrite32(val, ioaddr + (reg))
187 #define er8(reg)	ioread8(ioaddr + (reg))
188 #define er16(reg)	ioread16(ioaddr + (reg))
189 #define er32(reg)	ioread32(ioaddr + (reg))
190 
191 /* Offsets to registers, using the (ugh) SMC names. */
192 enum epic_registers {
193   COMMAND=0, INTSTAT=4, INTMASK=8, GENCTL=0x0C, NVCTL=0x10, EECTL=0x14,
194   PCIBurstCnt=0x18,
195   TEST1=0x1C, CRCCNT=0x20, ALICNT=0x24, MPCNT=0x28,	/* Rx error counters. */
196   MIICtrl=0x30, MIIData=0x34, MIICfg=0x38,
197   LAN0=64,						/* MAC address. */
198   MC0=80,						/* Multicast filter table. */
199   RxCtrl=96, TxCtrl=112, TxSTAT=0x74,
200   PRxCDAR=0x84, RxSTAT=0xA4, EarlyRx=0xB0, PTxCDAR=0xC4, TxThresh=0xDC,
201 };
202 
203 /* Interrupt register bits, using my own meaningful names. */
204 enum IntrStatus {
205 	TxIdle=0x40000, RxIdle=0x20000, IntrSummary=0x010000,
206 	PCIBusErr170=0x7000, PCIBusErr175=0x1000, PhyEvent175=0x8000,
207 	RxStarted=0x0800, RxEarlyWarn=0x0400, CntFull=0x0200, TxUnderrun=0x0100,
208 	TxEmpty=0x0080, TxDone=0x0020, RxError=0x0010,
209 	RxOverflow=0x0008, RxFull=0x0004, RxHeader=0x0002, RxDone=0x0001,
210 };
211 enum CommandBits {
212 	StopRx=1, StartRx=2, TxQueued=4, RxQueued=8,
213 	StopTxDMA=0x20, StopRxDMA=0x40, RestartTx=0x80,
214 };
215 
216 #define EpicRemoved	0xffffffff	/* Chip failed or removed (CardBus) */
217 
218 #define EpicNapiEvent	(TxEmpty | TxDone | \
219 			 RxDone | RxStarted | RxEarlyWarn | RxOverflow | RxFull)
220 #define EpicNormalEvent	(0x0000ffff & ~EpicNapiEvent)
221 
222 static const u16 media2miictl[16] = {
223 	0, 0x0C00, 0x0C00, 0x2000,  0x0100, 0x2100, 0, 0,
224 	0, 0, 0, 0,  0, 0, 0, 0 };
225 
226 /*
227  * The EPIC100 Rx and Tx buffer descriptors.  Note that these
228  * really ARE host-endian; it's not a misannotation.  We tell
229  * the card to byteswap them internally on big-endian hosts -
230  * look for #ifdef __BIG_ENDIAN in epic_open().
231  */
232 
233 struct epic_tx_desc {
234 	u32 txstatus;
235 	u32 bufaddr;
236 	u32 buflength;
237 	u32 next;
238 };
239 
240 struct epic_rx_desc {
241 	u32 rxstatus;
242 	u32 bufaddr;
243 	u32 buflength;
244 	u32 next;
245 };
246 
247 enum desc_status_bits {
248 	DescOwn=0x8000,
249 };
250 
251 #define PRIV_ALIGN	15 	/* Required alignment mask */
252 struct epic_private {
253 	struct epic_rx_desc *rx_ring;
254 	struct epic_tx_desc *tx_ring;
255 	/* The saved address of a sent-in-place packet/buffer, for skfree(). */
256 	struct sk_buff* tx_skbuff[TX_RING_SIZE];
257 	/* The addresses of receive-in-place skbuffs. */
258 	struct sk_buff* rx_skbuff[RX_RING_SIZE];
259 
260 	dma_addr_t tx_ring_dma;
261 	dma_addr_t rx_ring_dma;
262 
263 	/* Ring pointers. */
264 	spinlock_t lock;				/* Group with Tx control cache line. */
265 	spinlock_t napi_lock;
266 	struct napi_struct napi;
267 	unsigned int reschedule_in_poll;
268 	unsigned int cur_tx, dirty_tx;
269 
270 	unsigned int cur_rx, dirty_rx;
271 	u32 irq_mask;
272 	unsigned int rx_buf_sz;				/* Based on MTU+slack. */
273 
274 	void __iomem *ioaddr;
275 	struct pci_dev *pci_dev;			/* PCI bus location. */
276 	int chip_id, chip_flags;
277 
278 	struct timer_list timer;			/* Media selection timer. */
279 	int tx_threshold;
280 	unsigned char mc_filter[8];
281 	signed char phys[4];				/* MII device addresses. */
282 	u16 advertising;					/* NWay media advertisement */
283 	int mii_phy_cnt;
284 	struct mii_if_info mii;
285 	unsigned int tx_full:1;				/* The Tx queue is full. */
286 	unsigned int default_port:4;		/* Last dev->if_port value. */
287 };
288 
289 static int epic_open(struct net_device *dev);
290 static int read_eeprom(struct epic_private *, int);
291 static int mdio_read(struct net_device *dev, int phy_id, int location);
292 static void mdio_write(struct net_device *dev, int phy_id, int loc, int val);
293 static void epic_restart(struct net_device *dev);
294 static void epic_timer(unsigned long data);
295 static void epic_tx_timeout(struct net_device *dev);
296 static void epic_init_ring(struct net_device *dev);
297 static netdev_tx_t epic_start_xmit(struct sk_buff *skb,
298 				   struct net_device *dev);
299 static int epic_rx(struct net_device *dev, int budget);
300 static int epic_poll(struct napi_struct *napi, int budget);
301 static irqreturn_t epic_interrupt(int irq, void *dev_instance);
302 static int netdev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
303 static const struct ethtool_ops netdev_ethtool_ops;
304 static int epic_close(struct net_device *dev);
305 static struct net_device_stats *epic_get_stats(struct net_device *dev);
306 static void set_rx_mode(struct net_device *dev);
307 
308 static const struct net_device_ops epic_netdev_ops = {
309 	.ndo_open		= epic_open,
310 	.ndo_stop		= epic_close,
311 	.ndo_start_xmit		= epic_start_xmit,
312 	.ndo_tx_timeout 	= epic_tx_timeout,
313 	.ndo_get_stats		= epic_get_stats,
314 	.ndo_set_rx_mode	= set_rx_mode,
315 	.ndo_do_ioctl 		= netdev_ioctl,
316 	.ndo_change_mtu		= eth_change_mtu,
317 	.ndo_set_mac_address 	= eth_mac_addr,
318 	.ndo_validate_addr	= eth_validate_addr,
319 };
320 
321 static int epic_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
322 {
323 	static int card_idx = -1;
324 	void __iomem *ioaddr;
325 	int chip_idx = (int) ent->driver_data;
326 	int irq;
327 	struct net_device *dev;
328 	struct epic_private *ep;
329 	int i, ret, option = 0, duplex = 0;
330 	void *ring_space;
331 	dma_addr_t ring_dma;
332 
333 /* when built into the kernel, we only print version if device is found */
334 #ifndef MODULE
335 	pr_info_once("%s%s\n", version, version2);
336 #endif
337 
338 	card_idx++;
339 
340 	ret = pci_enable_device(pdev);
341 	if (ret)
342 		goto out;
343 	irq = pdev->irq;
344 
345 	if (pci_resource_len(pdev, 0) < EPIC_TOTAL_SIZE) {
346 		dev_err(&pdev->dev, "no PCI region space\n");
347 		ret = -ENODEV;
348 		goto err_out_disable;
349 	}
350 
351 	pci_set_master(pdev);
352 
353 	ret = pci_request_regions(pdev, DRV_NAME);
354 	if (ret < 0)
355 		goto err_out_disable;
356 
357 	ret = -ENOMEM;
358 
359 	dev = alloc_etherdev(sizeof (*ep));
360 	if (!dev)
361 		goto err_out_free_res;
362 
363 	SET_NETDEV_DEV(dev, &pdev->dev);
364 
365 	ioaddr = pci_iomap(pdev, EPIC_BAR, 0);
366 	if (!ioaddr) {
367 		dev_err(&pdev->dev, "ioremap failed\n");
368 		goto err_out_free_netdev;
369 	}
370 
371 	pci_set_drvdata(pdev, dev);
372 	ep = netdev_priv(dev);
373 	ep->ioaddr = ioaddr;
374 	ep->mii.dev = dev;
375 	ep->mii.mdio_read = mdio_read;
376 	ep->mii.mdio_write = mdio_write;
377 	ep->mii.phy_id_mask = 0x1f;
378 	ep->mii.reg_num_mask = 0x1f;
379 
380 	ring_space = pci_alloc_consistent(pdev, TX_TOTAL_SIZE, &ring_dma);
381 	if (!ring_space)
382 		goto err_out_iounmap;
383 	ep->tx_ring = ring_space;
384 	ep->tx_ring_dma = ring_dma;
385 
386 	ring_space = pci_alloc_consistent(pdev, RX_TOTAL_SIZE, &ring_dma);
387 	if (!ring_space)
388 		goto err_out_unmap_tx;
389 	ep->rx_ring = ring_space;
390 	ep->rx_ring_dma = ring_dma;
391 
392 	if (dev->mem_start) {
393 		option = dev->mem_start;
394 		duplex = (dev->mem_start & 16) ? 1 : 0;
395 	} else if (card_idx >= 0  &&  card_idx < MAX_UNITS) {
396 		if (options[card_idx] >= 0)
397 			option = options[card_idx];
398 		if (full_duplex[card_idx] >= 0)
399 			duplex = full_duplex[card_idx];
400 	}
401 
402 	spin_lock_init(&ep->lock);
403 	spin_lock_init(&ep->napi_lock);
404 	ep->reschedule_in_poll = 0;
405 
406 	/* Bring the chip out of low-power mode. */
407 	ew32(GENCTL, 0x4200);
408 	/* Magic?!  If we don't set this bit the MII interface won't work. */
409 	/* This magic is documented in SMSC app note 7.15 */
410 	for (i = 16; i > 0; i--)
411 		ew32(TEST1, 0x0008);
412 
413 	/* Turn on the MII transceiver. */
414 	ew32(MIICfg, 0x12);
415 	if (chip_idx == 1)
416 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
417 	ew32(GENCTL, 0x0200);
418 
419 	/* Note: the '175 does not have a serial EEPROM. */
420 	for (i = 0; i < 3; i++)
421 		((__le16 *)dev->dev_addr)[i] = cpu_to_le16(er16(LAN0 + i*4));
422 
423 	if (debug > 2) {
424 		dev_dbg(&pdev->dev, "EEPROM contents:\n");
425 		for (i = 0; i < 64; i++)
426 			pr_cont(" %4.4x%s", read_eeprom(ep, i),
427 				   i % 16 == 15 ? "\n" : "");
428 	}
429 
430 	ep->pci_dev = pdev;
431 	ep->chip_id = chip_idx;
432 	ep->chip_flags = pci_id_tbl[chip_idx].drv_flags;
433 	ep->irq_mask =
434 		(ep->chip_flags & TYPE2_INTR ?  PCIBusErr175 : PCIBusErr170)
435 		 | CntFull | TxUnderrun | EpicNapiEvent;
436 
437 	/* Find the connected MII xcvrs.
438 	   Doing this in open() would allow detecting external xcvrs later, but
439 	   takes much time and no cards have external MII. */
440 	{
441 		int phy, phy_idx = 0;
442 		for (phy = 1; phy < 32 && phy_idx < sizeof(ep->phys); phy++) {
443 			int mii_status = mdio_read(dev, phy, MII_BMSR);
444 			if (mii_status != 0xffff  &&  mii_status != 0x0000) {
445 				ep->phys[phy_idx++] = phy;
446 				dev_info(&pdev->dev,
447 					"MII transceiver #%d control "
448 					"%4.4x status %4.4x.\n",
449 					phy, mdio_read(dev, phy, 0), mii_status);
450 			}
451 		}
452 		ep->mii_phy_cnt = phy_idx;
453 		if (phy_idx != 0) {
454 			phy = ep->phys[0];
455 			ep->mii.advertising = mdio_read(dev, phy, MII_ADVERTISE);
456 			dev_info(&pdev->dev,
457 				"Autonegotiation advertising %4.4x link "
458 				   "partner %4.4x.\n",
459 				   ep->mii.advertising, mdio_read(dev, phy, 5));
460 		} else if ( ! (ep->chip_flags & NO_MII)) {
461 			dev_warn(&pdev->dev,
462 				"***WARNING***: No MII transceiver found!\n");
463 			/* Use the known PHY address of the EPII. */
464 			ep->phys[0] = 3;
465 		}
466 		ep->mii.phy_id = ep->phys[0];
467 	}
468 
469 	/* Turn off the MII xcvr (175 only!), leave the chip in low-power mode. */
470 	if (ep->chip_flags & MII_PWRDWN)
471 		ew32(NVCTL, er32(NVCTL) & ~0x483c);
472 	ew32(GENCTL, 0x0008);
473 
474 	/* The lower four bits are the media type. */
475 	if (duplex) {
476 		ep->mii.force_media = ep->mii.full_duplex = 1;
477 		dev_info(&pdev->dev, "Forced full duplex requested.\n");
478 	}
479 	dev->if_port = ep->default_port = option;
480 
481 	/* The Epic-specific entries in the device structure. */
482 	dev->netdev_ops = &epic_netdev_ops;
483 	dev->ethtool_ops = &netdev_ethtool_ops;
484 	dev->watchdog_timeo = TX_TIMEOUT;
485 	netif_napi_add(dev, &ep->napi, epic_poll, 64);
486 
487 	ret = register_netdev(dev);
488 	if (ret < 0)
489 		goto err_out_unmap_rx;
490 
491 	netdev_info(dev, "%s at %lx, IRQ %d, %pM\n",
492 		    pci_id_tbl[chip_idx].name,
493 		    (long)pci_resource_start(pdev, EPIC_BAR), pdev->irq,
494 		    dev->dev_addr);
495 
496 out:
497 	return ret;
498 
499 err_out_unmap_rx:
500 	pci_free_consistent(pdev, RX_TOTAL_SIZE, ep->rx_ring, ep->rx_ring_dma);
501 err_out_unmap_tx:
502 	pci_free_consistent(pdev, TX_TOTAL_SIZE, ep->tx_ring, ep->tx_ring_dma);
503 err_out_iounmap:
504 	pci_iounmap(pdev, ioaddr);
505 err_out_free_netdev:
506 	free_netdev(dev);
507 err_out_free_res:
508 	pci_release_regions(pdev);
509 err_out_disable:
510 	pci_disable_device(pdev);
511 	goto out;
512 }
513 
514 /* Serial EEPROM section. */
515 
516 /*  EEPROM_Ctrl bits. */
517 #define EE_SHIFT_CLK	0x04	/* EEPROM shift clock. */
518 #define EE_CS			0x02	/* EEPROM chip select. */
519 #define EE_DATA_WRITE	0x08	/* EEPROM chip data in. */
520 #define EE_WRITE_0		0x01
521 #define EE_WRITE_1		0x09
522 #define EE_DATA_READ	0x10	/* EEPROM chip data out. */
523 #define EE_ENB			(0x0001 | EE_CS)
524 
525 /* Delay between EEPROM clock transitions.
526    This serves to flush the operation to the PCI bus.
527  */
528 
529 #define eeprom_delay()	er32(EECTL)
530 
531 /* The EEPROM commands include the alway-set leading bit. */
532 #define EE_WRITE_CMD	(5 << 6)
533 #define EE_READ64_CMD	(6 << 6)
534 #define EE_READ256_CMD	(6 << 8)
535 #define EE_ERASE_CMD	(7 << 6)
536 
537 static void epic_disable_int(struct net_device *dev, struct epic_private *ep)
538 {
539 	void __iomem *ioaddr = ep->ioaddr;
540 
541 	ew32(INTMASK, 0x00000000);
542 }
543 
544 static inline void __epic_pci_commit(void __iomem *ioaddr)
545 {
546 #ifndef USE_IO_OPS
547 	er32(INTMASK);
548 #endif
549 }
550 
551 static inline void epic_napi_irq_off(struct net_device *dev,
552 				     struct epic_private *ep)
553 {
554 	void __iomem *ioaddr = ep->ioaddr;
555 
556 	ew32(INTMASK, ep->irq_mask & ~EpicNapiEvent);
557 	__epic_pci_commit(ioaddr);
558 }
559 
560 static inline void epic_napi_irq_on(struct net_device *dev,
561 				    struct epic_private *ep)
562 {
563 	void __iomem *ioaddr = ep->ioaddr;
564 
565 	/* No need to commit possible posted write */
566 	ew32(INTMASK, ep->irq_mask | EpicNapiEvent);
567 }
568 
569 static int read_eeprom(struct epic_private *ep, int location)
570 {
571 	void __iomem *ioaddr = ep->ioaddr;
572 	int i;
573 	int retval = 0;
574 	int read_cmd = location |
575 		(er32(EECTL) & 0x40 ? EE_READ64_CMD : EE_READ256_CMD);
576 
577 	ew32(EECTL, EE_ENB & ~EE_CS);
578 	ew32(EECTL, EE_ENB);
579 
580 	/* Shift the read command bits out. */
581 	for (i = 12; i >= 0; i--) {
582 		short dataval = (read_cmd & (1 << i)) ? EE_WRITE_1 : EE_WRITE_0;
583 		ew32(EECTL, EE_ENB | dataval);
584 		eeprom_delay();
585 		ew32(EECTL, EE_ENB | dataval | EE_SHIFT_CLK);
586 		eeprom_delay();
587 	}
588 	ew32(EECTL, EE_ENB);
589 
590 	for (i = 16; i > 0; i--) {
591 		ew32(EECTL, EE_ENB | EE_SHIFT_CLK);
592 		eeprom_delay();
593 		retval = (retval << 1) | ((er32(EECTL) & EE_DATA_READ) ? 1 : 0);
594 		ew32(EECTL, EE_ENB);
595 		eeprom_delay();
596 	}
597 
598 	/* Terminate the EEPROM access. */
599 	ew32(EECTL, EE_ENB & ~EE_CS);
600 	return retval;
601 }
602 
603 #define MII_READOP		1
604 #define MII_WRITEOP		2
605 static int mdio_read(struct net_device *dev, int phy_id, int location)
606 {
607 	struct epic_private *ep = netdev_priv(dev);
608 	void __iomem *ioaddr = ep->ioaddr;
609 	int read_cmd = (phy_id << 9) | (location << 4) | MII_READOP;
610 	int i;
611 
612 	ew32(MIICtrl, read_cmd);
613 	/* Typical operation takes 25 loops. */
614 	for (i = 400; i > 0; i--) {
615 		barrier();
616 		if ((er32(MIICtrl) & MII_READOP) == 0) {
617 			/* Work around read failure bug. */
618 			if (phy_id == 1 && location < 6 &&
619 			    er16(MIIData) == 0xffff) {
620 				ew32(MIICtrl, read_cmd);
621 				continue;
622 			}
623 			return er16(MIIData);
624 		}
625 	}
626 	return 0xffff;
627 }
628 
629 static void mdio_write(struct net_device *dev, int phy_id, int loc, int value)
630 {
631 	struct epic_private *ep = netdev_priv(dev);
632 	void __iomem *ioaddr = ep->ioaddr;
633 	int i;
634 
635 	ew16(MIIData, value);
636 	ew32(MIICtrl, (phy_id << 9) | (loc << 4) | MII_WRITEOP);
637 	for (i = 10000; i > 0; i--) {
638 		barrier();
639 		if ((er32(MIICtrl) & MII_WRITEOP) == 0)
640 			break;
641 	}
642 }
643 
644 
645 static int epic_open(struct net_device *dev)
646 {
647 	struct epic_private *ep = netdev_priv(dev);
648 	void __iomem *ioaddr = ep->ioaddr;
649 	const int irq = ep->pci_dev->irq;
650 	int rc, i;
651 
652 	/* Soft reset the chip. */
653 	ew32(GENCTL, 0x4001);
654 
655 	napi_enable(&ep->napi);
656 	rc = request_irq(irq, epic_interrupt, IRQF_SHARED, dev->name, dev);
657 	if (rc) {
658 		napi_disable(&ep->napi);
659 		return rc;
660 	}
661 
662 	epic_init_ring(dev);
663 
664 	ew32(GENCTL, 0x4000);
665 	/* This magic is documented in SMSC app note 7.15 */
666 	for (i = 16; i > 0; i--)
667 		ew32(TEST1, 0x0008);
668 
669 	/* Pull the chip out of low-power mode, enable interrupts, and set for
670 	   PCI read multiple.  The MIIcfg setting and strange write order are
671 	   required by the details of which bits are reset and the transceiver
672 	   wiring on the Ositech CardBus card.
673 	*/
674 #if 0
675 	ew32(MIICfg, dev->if_port == 1 ? 0x13 : 0x12);
676 #endif
677 	if (ep->chip_flags & MII_PWRDWN)
678 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
679 
680 	/* Tell the chip to byteswap descriptors on big-endian hosts */
681 #ifdef __BIG_ENDIAN
682 	ew32(GENCTL, 0x4432 | (RX_FIFO_THRESH << 8));
683 	er32(GENCTL);
684 	ew32(GENCTL, 0x0432 | (RX_FIFO_THRESH << 8));
685 #else
686 	ew32(GENCTL, 0x4412 | (RX_FIFO_THRESH << 8));
687 	er32(GENCTL);
688 	ew32(GENCTL, 0x0412 | (RX_FIFO_THRESH << 8));
689 #endif
690 
691 	udelay(20); /* Looks like EPII needs that if you want reliable RX init. FIXME: pci posting bug? */
692 
693 	for (i = 0; i < 3; i++)
694 		ew32(LAN0 + i*4, le16_to_cpu(((__le16*)dev->dev_addr)[i]));
695 
696 	ep->tx_threshold = TX_FIFO_THRESH;
697 	ew32(TxThresh, ep->tx_threshold);
698 
699 	if (media2miictl[dev->if_port & 15]) {
700 		if (ep->mii_phy_cnt)
701 			mdio_write(dev, ep->phys[0], MII_BMCR, media2miictl[dev->if_port&15]);
702 		if (dev->if_port == 1) {
703 			if (debug > 1)
704 				netdev_info(dev, "Using the 10base2 transceiver, MII status %4.4x.\n",
705 					    mdio_read(dev, ep->phys[0], MII_BMSR));
706 		}
707 	} else {
708 		int mii_lpa = mdio_read(dev, ep->phys[0], MII_LPA);
709 		if (mii_lpa != 0xffff) {
710 			if ((mii_lpa & LPA_100FULL) || (mii_lpa & 0x01C0) == LPA_10FULL)
711 				ep->mii.full_duplex = 1;
712 			else if (! (mii_lpa & LPA_LPACK))
713 				mdio_write(dev, ep->phys[0], MII_BMCR, BMCR_ANENABLE|BMCR_ANRESTART);
714 			if (debug > 1)
715 				netdev_info(dev, "Setting %s-duplex based on MII xcvr %d register read of %4.4x.\n",
716 					    ep->mii.full_duplex ? "full"
717 								: "half",
718 					    ep->phys[0], mii_lpa);
719 		}
720 	}
721 
722 	ew32(TxCtrl, ep->mii.full_duplex ? 0x7f : 0x79);
723 	ew32(PRxCDAR, ep->rx_ring_dma);
724 	ew32(PTxCDAR, ep->tx_ring_dma);
725 
726 	/* Start the chip's Rx process. */
727 	set_rx_mode(dev);
728 	ew32(COMMAND, StartRx | RxQueued);
729 
730 	netif_start_queue(dev);
731 
732 	/* Enable interrupts by setting the interrupt mask. */
733 	ew32(INTMASK, RxError | RxHeader | EpicNapiEvent | CntFull |
734 	     ((ep->chip_flags & TYPE2_INTR) ? PCIBusErr175 : PCIBusErr170) |
735 	     TxUnderrun);
736 
737 	if (debug > 1) {
738 		netdev_dbg(dev, "epic_open() ioaddr %p IRQ %d status %4.4x %s-duplex.\n",
739 			   ioaddr, irq, er32(GENCTL),
740 			   ep->mii.full_duplex ? "full" : "half");
741 	}
742 
743 	/* Set the timer to switch to check for link beat and perhaps switch
744 	   to an alternate media type. */
745 	init_timer(&ep->timer);
746 	ep->timer.expires = jiffies + 3*HZ;
747 	ep->timer.data = (unsigned long)dev;
748 	ep->timer.function = epic_timer;				/* timer handler */
749 	add_timer(&ep->timer);
750 
751 	return rc;
752 }
753 
754 /* Reset the chip to recover from a PCI transaction error.
755    This may occur at interrupt time. */
756 static void epic_pause(struct net_device *dev)
757 {
758 	struct net_device_stats *stats = &dev->stats;
759 	struct epic_private *ep = netdev_priv(dev);
760 	void __iomem *ioaddr = ep->ioaddr;
761 
762 	netif_stop_queue (dev);
763 
764 	/* Disable interrupts by clearing the interrupt mask. */
765 	ew32(INTMASK, 0x00000000);
766 	/* Stop the chip's Tx and Rx DMA processes. */
767 	ew16(COMMAND, StopRx | StopTxDMA | StopRxDMA);
768 
769 	/* Update the error counts. */
770 	if (er16(COMMAND) != 0xffff) {
771 		stats->rx_missed_errors	+= er8(MPCNT);
772 		stats->rx_frame_errors	+= er8(ALICNT);
773 		stats->rx_crc_errors	+= er8(CRCCNT);
774 	}
775 
776 	/* Remove the packets on the Rx queue. */
777 	epic_rx(dev, RX_RING_SIZE);
778 }
779 
780 static void epic_restart(struct net_device *dev)
781 {
782 	struct epic_private *ep = netdev_priv(dev);
783 	void __iomem *ioaddr = ep->ioaddr;
784 	int i;
785 
786 	/* Soft reset the chip. */
787 	ew32(GENCTL, 0x4001);
788 
789 	netdev_dbg(dev, "Restarting the EPIC chip, Rx %d/%d Tx %d/%d.\n",
790 		   ep->cur_rx, ep->dirty_rx, ep->dirty_tx, ep->cur_tx);
791 	udelay(1);
792 
793 	/* This magic is documented in SMSC app note 7.15 */
794 	for (i = 16; i > 0; i--)
795 		ew32(TEST1, 0x0008);
796 
797 #ifdef __BIG_ENDIAN
798 	ew32(GENCTL, 0x0432 | (RX_FIFO_THRESH << 8));
799 #else
800 	ew32(GENCTL, 0x0412 | (RX_FIFO_THRESH << 8));
801 #endif
802 	ew32(MIICfg, dev->if_port == 1 ? 0x13 : 0x12);
803 	if (ep->chip_flags & MII_PWRDWN)
804 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
805 
806 	for (i = 0; i < 3; i++)
807 		ew32(LAN0 + i*4, le16_to_cpu(((__le16*)dev->dev_addr)[i]));
808 
809 	ep->tx_threshold = TX_FIFO_THRESH;
810 	ew32(TxThresh, ep->tx_threshold);
811 	ew32(TxCtrl, ep->mii.full_duplex ? 0x7f : 0x79);
812 	ew32(PRxCDAR, ep->rx_ring_dma +
813 	     (ep->cur_rx % RX_RING_SIZE) * sizeof(struct epic_rx_desc));
814 	ew32(PTxCDAR, ep->tx_ring_dma +
815 	     (ep->dirty_tx % TX_RING_SIZE) * sizeof(struct epic_tx_desc));
816 
817 	/* Start the chip's Rx process. */
818 	set_rx_mode(dev);
819 	ew32(COMMAND, StartRx | RxQueued);
820 
821 	/* Enable interrupts by setting the interrupt mask. */
822 	ew32(INTMASK, RxError | RxHeader | EpicNapiEvent | CntFull |
823 	     ((ep->chip_flags & TYPE2_INTR) ? PCIBusErr175 : PCIBusErr170) |
824 	     TxUnderrun);
825 
826 	netdev_dbg(dev, "epic_restart() done, cmd status %4.4x, ctl %4.4x interrupt %4.4x.\n",
827 		   er32(COMMAND), er32(GENCTL), er32(INTSTAT));
828 }
829 
830 static void check_media(struct net_device *dev)
831 {
832 	struct epic_private *ep = netdev_priv(dev);
833 	void __iomem *ioaddr = ep->ioaddr;
834 	int mii_lpa = ep->mii_phy_cnt ? mdio_read(dev, ep->phys[0], MII_LPA) : 0;
835 	int negotiated = mii_lpa & ep->mii.advertising;
836 	int duplex = (negotiated & 0x0100) || (negotiated & 0x01C0) == 0x0040;
837 
838 	if (ep->mii.force_media)
839 		return;
840 	if (mii_lpa == 0xffff)		/* Bogus read */
841 		return;
842 	if (ep->mii.full_duplex != duplex) {
843 		ep->mii.full_duplex = duplex;
844 		netdev_info(dev, "Setting %s-duplex based on MII #%d link partner capability of %4.4x.\n",
845 			    ep->mii.full_duplex ? "full" : "half",
846 			    ep->phys[0], mii_lpa);
847 		ew32(TxCtrl, ep->mii.full_duplex ? 0x7F : 0x79);
848 	}
849 }
850 
851 static void epic_timer(unsigned long data)
852 {
853 	struct net_device *dev = (struct net_device *)data;
854 	struct epic_private *ep = netdev_priv(dev);
855 	void __iomem *ioaddr = ep->ioaddr;
856 	int next_tick = 5*HZ;
857 
858 	if (debug > 3) {
859 		netdev_dbg(dev, "Media monitor tick, Tx status %8.8x.\n",
860 			   er32(TxSTAT));
861 		netdev_dbg(dev, "Other registers are IntMask %4.4x IntStatus %4.4x RxStatus %4.4x.\n",
862 			   er32(INTMASK), er32(INTSTAT), er32(RxSTAT));
863 	}
864 
865 	check_media(dev);
866 
867 	ep->timer.expires = jiffies + next_tick;
868 	add_timer(&ep->timer);
869 }
870 
871 static void epic_tx_timeout(struct net_device *dev)
872 {
873 	struct epic_private *ep = netdev_priv(dev);
874 	void __iomem *ioaddr = ep->ioaddr;
875 
876 	if (debug > 0) {
877 		netdev_warn(dev, "Transmit timeout using MII device, Tx status %4.4x.\n",
878 			    er16(TxSTAT));
879 		if (debug > 1) {
880 			netdev_dbg(dev, "Tx indices: dirty_tx %d, cur_tx %d.\n",
881 				   ep->dirty_tx, ep->cur_tx);
882 		}
883 	}
884 	if (er16(TxSTAT) & 0x10) {		/* Tx FIFO underflow. */
885 		dev->stats.tx_fifo_errors++;
886 		ew32(COMMAND, RestartTx);
887 	} else {
888 		epic_restart(dev);
889 		ew32(COMMAND, TxQueued);
890 	}
891 
892 	netif_trans_update(dev); /* prevent tx timeout */
893 	dev->stats.tx_errors++;
894 	if (!ep->tx_full)
895 		netif_wake_queue(dev);
896 }
897 
898 /* Initialize the Rx and Tx rings, along with various 'dev' bits. */
899 static void epic_init_ring(struct net_device *dev)
900 {
901 	struct epic_private *ep = netdev_priv(dev);
902 	int i;
903 
904 	ep->tx_full = 0;
905 	ep->dirty_tx = ep->cur_tx = 0;
906 	ep->cur_rx = ep->dirty_rx = 0;
907 	ep->rx_buf_sz = (dev->mtu <= 1500 ? PKT_BUF_SZ : dev->mtu + 32);
908 
909 	/* Initialize all Rx descriptors. */
910 	for (i = 0; i < RX_RING_SIZE; i++) {
911 		ep->rx_ring[i].rxstatus = 0;
912 		ep->rx_ring[i].buflength = ep->rx_buf_sz;
913 		ep->rx_ring[i].next = ep->rx_ring_dma +
914 				      (i+1)*sizeof(struct epic_rx_desc);
915 		ep->rx_skbuff[i] = NULL;
916 	}
917 	/* Mark the last entry as wrapping the ring. */
918 	ep->rx_ring[i-1].next = ep->rx_ring_dma;
919 
920 	/* Fill in the Rx buffers.  Handle allocation failure gracefully. */
921 	for (i = 0; i < RX_RING_SIZE; i++) {
922 		struct sk_buff *skb = netdev_alloc_skb(dev, ep->rx_buf_sz + 2);
923 		ep->rx_skbuff[i] = skb;
924 		if (skb == NULL)
925 			break;
926 		skb_reserve(skb, 2);	/* 16 byte align the IP header. */
927 		ep->rx_ring[i].bufaddr = pci_map_single(ep->pci_dev,
928 			skb->data, ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
929 		ep->rx_ring[i].rxstatus = DescOwn;
930 	}
931 	ep->dirty_rx = (unsigned int)(i - RX_RING_SIZE);
932 
933 	/* The Tx buffer descriptor is filled in as needed, but we
934 	   do need to clear the ownership bit. */
935 	for (i = 0; i < TX_RING_SIZE; i++) {
936 		ep->tx_skbuff[i] = NULL;
937 		ep->tx_ring[i].txstatus = 0x0000;
938 		ep->tx_ring[i].next = ep->tx_ring_dma +
939 			(i+1)*sizeof(struct epic_tx_desc);
940 	}
941 	ep->tx_ring[i-1].next = ep->tx_ring_dma;
942 }
943 
944 static netdev_tx_t epic_start_xmit(struct sk_buff *skb, struct net_device *dev)
945 {
946 	struct epic_private *ep = netdev_priv(dev);
947 	void __iomem *ioaddr = ep->ioaddr;
948 	int entry, free_count;
949 	u32 ctrl_word;
950 	unsigned long flags;
951 
952 	if (skb_padto(skb, ETH_ZLEN))
953 		return NETDEV_TX_OK;
954 
955 	/* Caution: the write order is important here, set the field with the
956 	   "ownership" bit last. */
957 
958 	/* Calculate the next Tx descriptor entry. */
959 	spin_lock_irqsave(&ep->lock, flags);
960 	free_count = ep->cur_tx - ep->dirty_tx;
961 	entry = ep->cur_tx % TX_RING_SIZE;
962 
963 	ep->tx_skbuff[entry] = skb;
964 	ep->tx_ring[entry].bufaddr = pci_map_single(ep->pci_dev, skb->data,
965 		 			            skb->len, PCI_DMA_TODEVICE);
966 	if (free_count < TX_QUEUE_LEN/2) {/* Typical path */
967 		ctrl_word = 0x100000; /* No interrupt */
968 	} else if (free_count == TX_QUEUE_LEN/2) {
969 		ctrl_word = 0x140000; /* Tx-done intr. */
970 	} else if (free_count < TX_QUEUE_LEN - 1) {
971 		ctrl_word = 0x100000; /* No Tx-done intr. */
972 	} else {
973 		/* Leave room for an additional entry. */
974 		ctrl_word = 0x140000; /* Tx-done intr. */
975 		ep->tx_full = 1;
976 	}
977 	ep->tx_ring[entry].buflength = ctrl_word | skb->len;
978 	ep->tx_ring[entry].txstatus =
979 		((skb->len >= ETH_ZLEN ? skb->len : ETH_ZLEN) << 16)
980 			    | DescOwn;
981 
982 	ep->cur_tx++;
983 	if (ep->tx_full)
984 		netif_stop_queue(dev);
985 
986 	spin_unlock_irqrestore(&ep->lock, flags);
987 	/* Trigger an immediate transmit demand. */
988 	ew32(COMMAND, TxQueued);
989 
990 	if (debug > 4)
991 		netdev_dbg(dev, "Queued Tx packet size %d to slot %d, flag %2.2x Tx status %8.8x.\n",
992 			   skb->len, entry, ctrl_word, er32(TxSTAT));
993 
994 	return NETDEV_TX_OK;
995 }
996 
997 static void epic_tx_error(struct net_device *dev, struct epic_private *ep,
998 			  int status)
999 {
1000 	struct net_device_stats *stats = &dev->stats;
1001 
1002 #ifndef final_version
1003 	/* There was an major error, log it. */
1004 	if (debug > 1)
1005 		netdev_dbg(dev, "Transmit error, Tx status %8.8x.\n",
1006 			   status);
1007 #endif
1008 	stats->tx_errors++;
1009 	if (status & 0x1050)
1010 		stats->tx_aborted_errors++;
1011 	if (status & 0x0008)
1012 		stats->tx_carrier_errors++;
1013 	if (status & 0x0040)
1014 		stats->tx_window_errors++;
1015 	if (status & 0x0010)
1016 		stats->tx_fifo_errors++;
1017 }
1018 
1019 static void epic_tx(struct net_device *dev, struct epic_private *ep)
1020 {
1021 	unsigned int dirty_tx, cur_tx;
1022 
1023 	/*
1024 	 * Note: if this lock becomes a problem we can narrow the locked
1025 	 * region at the cost of occasionally grabbing the lock more times.
1026 	 */
1027 	cur_tx = ep->cur_tx;
1028 	for (dirty_tx = ep->dirty_tx; cur_tx - dirty_tx > 0; dirty_tx++) {
1029 		struct sk_buff *skb;
1030 		int entry = dirty_tx % TX_RING_SIZE;
1031 		int txstatus = ep->tx_ring[entry].txstatus;
1032 
1033 		if (txstatus & DescOwn)
1034 			break;	/* It still hasn't been Txed */
1035 
1036 		if (likely(txstatus & 0x0001)) {
1037 			dev->stats.collisions += (txstatus >> 8) & 15;
1038 			dev->stats.tx_packets++;
1039 			dev->stats.tx_bytes += ep->tx_skbuff[entry]->len;
1040 		} else
1041 			epic_tx_error(dev, ep, txstatus);
1042 
1043 		/* Free the original skb. */
1044 		skb = ep->tx_skbuff[entry];
1045 		pci_unmap_single(ep->pci_dev, ep->tx_ring[entry].bufaddr,
1046 				 skb->len, PCI_DMA_TODEVICE);
1047 		dev_kfree_skb_irq(skb);
1048 		ep->tx_skbuff[entry] = NULL;
1049 	}
1050 
1051 #ifndef final_version
1052 	if (cur_tx - dirty_tx > TX_RING_SIZE) {
1053 		netdev_warn(dev, "Out-of-sync dirty pointer, %d vs. %d, full=%d.\n",
1054 			    dirty_tx, cur_tx, ep->tx_full);
1055 		dirty_tx += TX_RING_SIZE;
1056 	}
1057 #endif
1058 	ep->dirty_tx = dirty_tx;
1059 	if (ep->tx_full && cur_tx - dirty_tx < TX_QUEUE_LEN - 4) {
1060 		/* The ring is no longer full, allow new TX entries. */
1061 		ep->tx_full = 0;
1062 		netif_wake_queue(dev);
1063 	}
1064 }
1065 
1066 /* The interrupt handler does all of the Rx thread work and cleans up
1067    after the Tx thread. */
1068 static irqreturn_t epic_interrupt(int irq, void *dev_instance)
1069 {
1070 	struct net_device *dev = dev_instance;
1071 	struct epic_private *ep = netdev_priv(dev);
1072 	void __iomem *ioaddr = ep->ioaddr;
1073 	unsigned int handled = 0;
1074 	int status;
1075 
1076 	status = er32(INTSTAT);
1077 	/* Acknowledge all of the current interrupt sources ASAP. */
1078 	ew32(INTSTAT, status & EpicNormalEvent);
1079 
1080 	if (debug > 4) {
1081 		netdev_dbg(dev, "Interrupt, status=%#8.8x new intstat=%#8.8x.\n",
1082 			   status, er32(INTSTAT));
1083 	}
1084 
1085 	if ((status & IntrSummary) == 0)
1086 		goto out;
1087 
1088 	handled = 1;
1089 
1090 	if ((status & EpicNapiEvent) && !ep->reschedule_in_poll) {
1091 		spin_lock(&ep->napi_lock);
1092 		if (napi_schedule_prep(&ep->napi)) {
1093 			epic_napi_irq_off(dev, ep);
1094 			__napi_schedule(&ep->napi);
1095 		} else
1096 			ep->reschedule_in_poll++;
1097 		spin_unlock(&ep->napi_lock);
1098 	}
1099 	status &= ~EpicNapiEvent;
1100 
1101 	/* Check uncommon events all at once. */
1102 	if (status & (CntFull | TxUnderrun | PCIBusErr170 | PCIBusErr175)) {
1103 		struct net_device_stats *stats = &dev->stats;
1104 
1105 		if (status == EpicRemoved)
1106 			goto out;
1107 
1108 		/* Always update the error counts to avoid overhead later. */
1109 		stats->rx_missed_errors	+= er8(MPCNT);
1110 		stats->rx_frame_errors	+= er8(ALICNT);
1111 		stats->rx_crc_errors	+= er8(CRCCNT);
1112 
1113 		if (status & TxUnderrun) { /* Tx FIFO underflow. */
1114 			stats->tx_fifo_errors++;
1115 			ew32(TxThresh, ep->tx_threshold += 128);
1116 			/* Restart the transmit process. */
1117 			ew32(COMMAND, RestartTx);
1118 		}
1119 		if (status & PCIBusErr170) {
1120 			netdev_err(dev, "PCI Bus Error! status %4.4x.\n",
1121 				   status);
1122 			epic_pause(dev);
1123 			epic_restart(dev);
1124 		}
1125 		/* Clear all error sources. */
1126 		ew32(INTSTAT, status & 0x7f18);
1127 	}
1128 
1129 out:
1130 	if (debug > 3) {
1131 		netdev_dbg(dev, "exit interrupt, intr_status=%#4.4x.\n",
1132 			   status);
1133 	}
1134 
1135 	return IRQ_RETVAL(handled);
1136 }
1137 
1138 static int epic_rx(struct net_device *dev, int budget)
1139 {
1140 	struct epic_private *ep = netdev_priv(dev);
1141 	int entry = ep->cur_rx % RX_RING_SIZE;
1142 	int rx_work_limit = ep->dirty_rx + RX_RING_SIZE - ep->cur_rx;
1143 	int work_done = 0;
1144 
1145 	if (debug > 4)
1146 		netdev_dbg(dev, " In epic_rx(), entry %d %8.8x.\n", entry,
1147 			   ep->rx_ring[entry].rxstatus);
1148 
1149 	if (rx_work_limit > budget)
1150 		rx_work_limit = budget;
1151 
1152 	/* If we own the next entry, it's a new packet. Send it up. */
1153 	while ((ep->rx_ring[entry].rxstatus & DescOwn) == 0) {
1154 		int status = ep->rx_ring[entry].rxstatus;
1155 
1156 		if (debug > 4)
1157 			netdev_dbg(dev, "  epic_rx() status was %8.8x.\n",
1158 				   status);
1159 		if (--rx_work_limit < 0)
1160 			break;
1161 		if (status & 0x2006) {
1162 			if (debug > 2)
1163 				netdev_dbg(dev, "epic_rx() error status was %8.8x.\n",
1164 					   status);
1165 			if (status & 0x2000) {
1166 				netdev_warn(dev, "Oversized Ethernet frame spanned multiple buffers, status %4.4x!\n",
1167 					    status);
1168 				dev->stats.rx_length_errors++;
1169 			} else if (status & 0x0006)
1170 				/* Rx Frame errors are counted in hardware. */
1171 				dev->stats.rx_errors++;
1172 		} else {
1173 			/* Malloc up new buffer, compatible with net-2e. */
1174 			/* Omit the four octet CRC from the length. */
1175 			short pkt_len = (status >> 16) - 4;
1176 			struct sk_buff *skb;
1177 
1178 			if (pkt_len > PKT_BUF_SZ - 4) {
1179 				netdev_err(dev, "Oversized Ethernet frame, status %x %d bytes.\n",
1180 					   status, pkt_len);
1181 				pkt_len = 1514;
1182 			}
1183 			/* Check if the packet is long enough to accept without copying
1184 			   to a minimally-sized skbuff. */
1185 			if (pkt_len < rx_copybreak &&
1186 			    (skb = netdev_alloc_skb(dev, pkt_len + 2)) != NULL) {
1187 				skb_reserve(skb, 2);	/* 16 byte align the IP header */
1188 				pci_dma_sync_single_for_cpu(ep->pci_dev,
1189 							    ep->rx_ring[entry].bufaddr,
1190 							    ep->rx_buf_sz,
1191 							    PCI_DMA_FROMDEVICE);
1192 				skb_copy_to_linear_data(skb, ep->rx_skbuff[entry]->data, pkt_len);
1193 				skb_put(skb, pkt_len);
1194 				pci_dma_sync_single_for_device(ep->pci_dev,
1195 							       ep->rx_ring[entry].bufaddr,
1196 							       ep->rx_buf_sz,
1197 							       PCI_DMA_FROMDEVICE);
1198 			} else {
1199 				pci_unmap_single(ep->pci_dev,
1200 					ep->rx_ring[entry].bufaddr,
1201 					ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
1202 				skb_put(skb = ep->rx_skbuff[entry], pkt_len);
1203 				ep->rx_skbuff[entry] = NULL;
1204 			}
1205 			skb->protocol = eth_type_trans(skb, dev);
1206 			netif_receive_skb(skb);
1207 			dev->stats.rx_packets++;
1208 			dev->stats.rx_bytes += pkt_len;
1209 		}
1210 		work_done++;
1211 		entry = (++ep->cur_rx) % RX_RING_SIZE;
1212 	}
1213 
1214 	/* Refill the Rx ring buffers. */
1215 	for (; ep->cur_rx - ep->dirty_rx > 0; ep->dirty_rx++) {
1216 		entry = ep->dirty_rx % RX_RING_SIZE;
1217 		if (ep->rx_skbuff[entry] == NULL) {
1218 			struct sk_buff *skb;
1219 			skb = ep->rx_skbuff[entry] = netdev_alloc_skb(dev, ep->rx_buf_sz + 2);
1220 			if (skb == NULL)
1221 				break;
1222 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
1223 			ep->rx_ring[entry].bufaddr = pci_map_single(ep->pci_dev,
1224 				skb->data, ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
1225 			work_done++;
1226 		}
1227 		/* AV: shouldn't we add a barrier here? */
1228 		ep->rx_ring[entry].rxstatus = DescOwn;
1229 	}
1230 	return work_done;
1231 }
1232 
1233 static void epic_rx_err(struct net_device *dev, struct epic_private *ep)
1234 {
1235 	void __iomem *ioaddr = ep->ioaddr;
1236 	int status;
1237 
1238 	status = er32(INTSTAT);
1239 
1240 	if (status == EpicRemoved)
1241 		return;
1242 	if (status & RxOverflow) 	/* Missed a Rx frame. */
1243 		dev->stats.rx_errors++;
1244 	if (status & (RxOverflow | RxFull))
1245 		ew16(COMMAND, RxQueued);
1246 }
1247 
1248 static int epic_poll(struct napi_struct *napi, int budget)
1249 {
1250 	struct epic_private *ep = container_of(napi, struct epic_private, napi);
1251 	struct net_device *dev = ep->mii.dev;
1252 	int work_done = 0;
1253 	void __iomem *ioaddr = ep->ioaddr;
1254 
1255 rx_action:
1256 
1257 	epic_tx(dev, ep);
1258 
1259 	work_done += epic_rx(dev, budget);
1260 
1261 	epic_rx_err(dev, ep);
1262 
1263 	if (work_done < budget) {
1264 		unsigned long flags;
1265 		int more;
1266 
1267 		/* A bit baroque but it avoids a (space hungry) spin_unlock */
1268 
1269 		spin_lock_irqsave(&ep->napi_lock, flags);
1270 
1271 		more = ep->reschedule_in_poll;
1272 		if (!more) {
1273 			__napi_complete(napi);
1274 			ew32(INTSTAT, EpicNapiEvent);
1275 			epic_napi_irq_on(dev, ep);
1276 		} else
1277 			ep->reschedule_in_poll--;
1278 
1279 		spin_unlock_irqrestore(&ep->napi_lock, flags);
1280 
1281 		if (more)
1282 			goto rx_action;
1283 	}
1284 
1285 	return work_done;
1286 }
1287 
1288 static int epic_close(struct net_device *dev)
1289 {
1290 	struct epic_private *ep = netdev_priv(dev);
1291 	struct pci_dev *pdev = ep->pci_dev;
1292 	void __iomem *ioaddr = ep->ioaddr;
1293 	struct sk_buff *skb;
1294 	int i;
1295 
1296 	netif_stop_queue(dev);
1297 	napi_disable(&ep->napi);
1298 
1299 	if (debug > 1)
1300 		netdev_dbg(dev, "Shutting down ethercard, status was %2.2x.\n",
1301 			   er32(INTSTAT));
1302 
1303 	del_timer_sync(&ep->timer);
1304 
1305 	epic_disable_int(dev, ep);
1306 
1307 	free_irq(pdev->irq, dev);
1308 
1309 	epic_pause(dev);
1310 
1311 	/* Free all the skbuffs in the Rx queue. */
1312 	for (i = 0; i < RX_RING_SIZE; i++) {
1313 		skb = ep->rx_skbuff[i];
1314 		ep->rx_skbuff[i] = NULL;
1315 		ep->rx_ring[i].rxstatus = 0;		/* Not owned by Epic chip. */
1316 		ep->rx_ring[i].buflength = 0;
1317 		if (skb) {
1318 			pci_unmap_single(pdev, ep->rx_ring[i].bufaddr,
1319 					 ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
1320 			dev_kfree_skb(skb);
1321 		}
1322 		ep->rx_ring[i].bufaddr = 0xBADF00D0; /* An invalid address. */
1323 	}
1324 	for (i = 0; i < TX_RING_SIZE; i++) {
1325 		skb = ep->tx_skbuff[i];
1326 		ep->tx_skbuff[i] = NULL;
1327 		if (!skb)
1328 			continue;
1329 		pci_unmap_single(pdev, ep->tx_ring[i].bufaddr, skb->len,
1330 				 PCI_DMA_TODEVICE);
1331 		dev_kfree_skb(skb);
1332 	}
1333 
1334 	/* Green! Leave the chip in low-power mode. */
1335 	ew32(GENCTL, 0x0008);
1336 
1337 	return 0;
1338 }
1339 
1340 static struct net_device_stats *epic_get_stats(struct net_device *dev)
1341 {
1342 	struct epic_private *ep = netdev_priv(dev);
1343 	void __iomem *ioaddr = ep->ioaddr;
1344 
1345 	if (netif_running(dev)) {
1346 		struct net_device_stats *stats = &dev->stats;
1347 
1348 		stats->rx_missed_errors	+= er8(MPCNT);
1349 		stats->rx_frame_errors	+= er8(ALICNT);
1350 		stats->rx_crc_errors	+= er8(CRCCNT);
1351 	}
1352 
1353 	return &dev->stats;
1354 }
1355 
1356 /* Set or clear the multicast filter for this adaptor.
1357    Note that we only use exclusion around actually queueing the
1358    new frame, not around filling ep->setup_frame.  This is non-deterministic
1359    when re-entered but still correct. */
1360 
1361 static void set_rx_mode(struct net_device *dev)
1362 {
1363 	struct epic_private *ep = netdev_priv(dev);
1364 	void __iomem *ioaddr = ep->ioaddr;
1365 	unsigned char mc_filter[8];		 /* Multicast hash filter */
1366 	int i;
1367 
1368 	if (dev->flags & IFF_PROMISC) {			/* Set promiscuous. */
1369 		ew32(RxCtrl, 0x002c);
1370 		/* Unconditionally log net taps. */
1371 		memset(mc_filter, 0xff, sizeof(mc_filter));
1372 	} else if ((!netdev_mc_empty(dev)) || (dev->flags & IFF_ALLMULTI)) {
1373 		/* There is apparently a chip bug, so the multicast filter
1374 		   is never enabled. */
1375 		/* Too many to filter perfectly -- accept all multicasts. */
1376 		memset(mc_filter, 0xff, sizeof(mc_filter));
1377 		ew32(RxCtrl, 0x000c);
1378 	} else if (netdev_mc_empty(dev)) {
1379 		ew32(RxCtrl, 0x0004);
1380 		return;
1381 	} else {					/* Never executed, for now. */
1382 		struct netdev_hw_addr *ha;
1383 
1384 		memset(mc_filter, 0, sizeof(mc_filter));
1385 		netdev_for_each_mc_addr(ha, dev) {
1386 			unsigned int bit_nr =
1387 				ether_crc_le(ETH_ALEN, ha->addr) & 0x3f;
1388 			mc_filter[bit_nr >> 3] |= (1 << bit_nr);
1389 		}
1390 	}
1391 	/* ToDo: perhaps we need to stop the Tx and Rx process here? */
1392 	if (memcmp(mc_filter, ep->mc_filter, sizeof(mc_filter))) {
1393 		for (i = 0; i < 4; i++)
1394 			ew16(MC0 + i*4, ((u16 *)mc_filter)[i]);
1395 		memcpy(ep->mc_filter, mc_filter, sizeof(mc_filter));
1396 	}
1397 }
1398 
1399 static void netdev_get_drvinfo (struct net_device *dev, struct ethtool_drvinfo *info)
1400 {
1401 	struct epic_private *np = netdev_priv(dev);
1402 
1403 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1404 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1405 	strlcpy(info->bus_info, pci_name(np->pci_dev), sizeof(info->bus_info));
1406 }
1407 
1408 static int netdev_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1409 {
1410 	struct epic_private *np = netdev_priv(dev);
1411 	int rc;
1412 
1413 	spin_lock_irq(&np->lock);
1414 	rc = mii_ethtool_gset(&np->mii, cmd);
1415 	spin_unlock_irq(&np->lock);
1416 
1417 	return rc;
1418 }
1419 
1420 static int netdev_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1421 {
1422 	struct epic_private *np = netdev_priv(dev);
1423 	int rc;
1424 
1425 	spin_lock_irq(&np->lock);
1426 	rc = mii_ethtool_sset(&np->mii, cmd);
1427 	spin_unlock_irq(&np->lock);
1428 
1429 	return rc;
1430 }
1431 
1432 static int netdev_nway_reset(struct net_device *dev)
1433 {
1434 	struct epic_private *np = netdev_priv(dev);
1435 	return mii_nway_restart(&np->mii);
1436 }
1437 
1438 static u32 netdev_get_link(struct net_device *dev)
1439 {
1440 	struct epic_private *np = netdev_priv(dev);
1441 	return mii_link_ok(&np->mii);
1442 }
1443 
1444 static u32 netdev_get_msglevel(struct net_device *dev)
1445 {
1446 	return debug;
1447 }
1448 
1449 static void netdev_set_msglevel(struct net_device *dev, u32 value)
1450 {
1451 	debug = value;
1452 }
1453 
1454 static int ethtool_begin(struct net_device *dev)
1455 {
1456 	struct epic_private *ep = netdev_priv(dev);
1457 	void __iomem *ioaddr = ep->ioaddr;
1458 
1459 	/* power-up, if interface is down */
1460 	if (!netif_running(dev)) {
1461 		ew32(GENCTL, 0x0200);
1462 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
1463 	}
1464 	return 0;
1465 }
1466 
1467 static void ethtool_complete(struct net_device *dev)
1468 {
1469 	struct epic_private *ep = netdev_priv(dev);
1470 	void __iomem *ioaddr = ep->ioaddr;
1471 
1472 	/* power-down, if interface is down */
1473 	if (!netif_running(dev)) {
1474 		ew32(GENCTL, 0x0008);
1475 		ew32(NVCTL, (er32(NVCTL) & ~0x483c) | 0x0000);
1476 	}
1477 }
1478 
1479 static const struct ethtool_ops netdev_ethtool_ops = {
1480 	.get_drvinfo		= netdev_get_drvinfo,
1481 	.get_settings		= netdev_get_settings,
1482 	.set_settings		= netdev_set_settings,
1483 	.nway_reset		= netdev_nway_reset,
1484 	.get_link		= netdev_get_link,
1485 	.get_msglevel		= netdev_get_msglevel,
1486 	.set_msglevel		= netdev_set_msglevel,
1487 	.begin			= ethtool_begin,
1488 	.complete		= ethtool_complete
1489 };
1490 
1491 static int netdev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1492 {
1493 	struct epic_private *np = netdev_priv(dev);
1494 	void __iomem *ioaddr = np->ioaddr;
1495 	struct mii_ioctl_data *data = if_mii(rq);
1496 	int rc;
1497 
1498 	/* power-up, if interface is down */
1499 	if (! netif_running(dev)) {
1500 		ew32(GENCTL, 0x0200);
1501 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
1502 	}
1503 
1504 	/* all non-ethtool ioctls (the SIOC[GS]MIIxxx ioctls) */
1505 	spin_lock_irq(&np->lock);
1506 	rc = generic_mii_ioctl(&np->mii, data, cmd, NULL);
1507 	spin_unlock_irq(&np->lock);
1508 
1509 	/* power-down, if interface is down */
1510 	if (! netif_running(dev)) {
1511 		ew32(GENCTL, 0x0008);
1512 		ew32(NVCTL, (er32(NVCTL) & ~0x483c) | 0x0000);
1513 	}
1514 	return rc;
1515 }
1516 
1517 
1518 static void epic_remove_one(struct pci_dev *pdev)
1519 {
1520 	struct net_device *dev = pci_get_drvdata(pdev);
1521 	struct epic_private *ep = netdev_priv(dev);
1522 
1523 	pci_free_consistent(pdev, TX_TOTAL_SIZE, ep->tx_ring, ep->tx_ring_dma);
1524 	pci_free_consistent(pdev, RX_TOTAL_SIZE, ep->rx_ring, ep->rx_ring_dma);
1525 	unregister_netdev(dev);
1526 	pci_iounmap(pdev, ep->ioaddr);
1527 	pci_release_regions(pdev);
1528 	free_netdev(dev);
1529 	pci_disable_device(pdev);
1530 	/* pci_power_off(pdev, -1); */
1531 }
1532 
1533 
1534 #ifdef CONFIG_PM
1535 
1536 static int epic_suspend (struct pci_dev *pdev, pm_message_t state)
1537 {
1538 	struct net_device *dev = pci_get_drvdata(pdev);
1539 	struct epic_private *ep = netdev_priv(dev);
1540 	void __iomem *ioaddr = ep->ioaddr;
1541 
1542 	if (!netif_running(dev))
1543 		return 0;
1544 	epic_pause(dev);
1545 	/* Put the chip into low-power mode. */
1546 	ew32(GENCTL, 0x0008);
1547 	/* pci_power_off(pdev, -1); */
1548 	return 0;
1549 }
1550 
1551 
1552 static int epic_resume (struct pci_dev *pdev)
1553 {
1554 	struct net_device *dev = pci_get_drvdata(pdev);
1555 
1556 	if (!netif_running(dev))
1557 		return 0;
1558 	epic_restart(dev);
1559 	/* pci_power_on(pdev); */
1560 	return 0;
1561 }
1562 
1563 #endif /* CONFIG_PM */
1564 
1565 
1566 static struct pci_driver epic_driver = {
1567 	.name		= DRV_NAME,
1568 	.id_table	= epic_pci_tbl,
1569 	.probe		= epic_init_one,
1570 	.remove		= epic_remove_one,
1571 #ifdef CONFIG_PM
1572 	.suspend	= epic_suspend,
1573 	.resume		= epic_resume,
1574 #endif /* CONFIG_PM */
1575 };
1576 
1577 
1578 static int __init epic_init (void)
1579 {
1580 /* when a module, this is printed whether or not devices are found in probe */
1581 #ifdef MODULE
1582 	pr_info("%s%s\n", version, version2);
1583 #endif
1584 
1585 	return pci_register_driver(&epic_driver);
1586 }
1587 
1588 
1589 static void __exit epic_cleanup (void)
1590 {
1591 	pci_unregister_driver (&epic_driver);
1592 }
1593 
1594 
1595 module_init(epic_init);
1596 module_exit(epic_cleanup);
1597