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 <linux/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 cur_tx, dirty_tx;
268 
269 	unsigned int cur_rx, dirty_rx;
270 	u32 irq_mask;
271 	unsigned int rx_buf_sz;				/* Based on MTU+slack. */
272 
273 	void __iomem *ioaddr;
274 	struct pci_dev *pci_dev;			/* PCI bus location. */
275 	int chip_id, chip_flags;
276 
277 	struct timer_list timer;			/* Media selection timer. */
278 	int tx_threshold;
279 	unsigned char mc_filter[8];
280 	signed char phys[4];				/* MII device addresses. */
281 	u16 advertising;					/* NWay media advertisement */
282 	int mii_phy_cnt;
283 	u32 ethtool_ops_nesting;
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(struct timer_list *t);
295 static void epic_tx_timeout(struct net_device *dev, unsigned int txqueue);
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_eth_ioctl		= netdev_ioctl,
316 	.ndo_set_mac_address 	= eth_mac_addr,
317 	.ndo_validate_addr	= eth_validate_addr,
318 };
319 
320 static int epic_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
321 {
322 	static int card_idx = -1;
323 	void __iomem *ioaddr;
324 	int chip_idx = (int) ent->driver_data;
325 	struct net_device *dev;
326 	struct epic_private *ep;
327 	int i, ret, option = 0, duplex = 0;
328 	void *ring_space;
329 	dma_addr_t ring_dma;
330 
331 /* when built into the kernel, we only print version if device is found */
332 #ifndef MODULE
333 	pr_info_once("%s%s\n", version, version2);
334 #endif
335 
336 	card_idx++;
337 
338 	ret = pci_enable_device(pdev);
339 	if (ret)
340 		goto out;
341 
342 	if (pci_resource_len(pdev, 0) < EPIC_TOTAL_SIZE) {
343 		dev_err(&pdev->dev, "no PCI region space\n");
344 		ret = -ENODEV;
345 		goto err_out_disable;
346 	}
347 
348 	pci_set_master(pdev);
349 
350 	ret = pci_request_regions(pdev, DRV_NAME);
351 	if (ret < 0)
352 		goto err_out_disable;
353 
354 	ret = -ENOMEM;
355 
356 	dev = alloc_etherdev(sizeof (*ep));
357 	if (!dev)
358 		goto err_out_free_res;
359 
360 	SET_NETDEV_DEV(dev, &pdev->dev);
361 
362 	ioaddr = pci_iomap(pdev, EPIC_BAR, 0);
363 	if (!ioaddr) {
364 		dev_err(&pdev->dev, "ioremap failed\n");
365 		goto err_out_free_netdev;
366 	}
367 
368 	pci_set_drvdata(pdev, dev);
369 	ep = netdev_priv(dev);
370 	ep->ioaddr = ioaddr;
371 	ep->mii.dev = dev;
372 	ep->mii.mdio_read = mdio_read;
373 	ep->mii.mdio_write = mdio_write;
374 	ep->mii.phy_id_mask = 0x1f;
375 	ep->mii.reg_num_mask = 0x1f;
376 
377 	ring_space = dma_alloc_coherent(&pdev->dev, TX_TOTAL_SIZE, &ring_dma,
378 					GFP_KERNEL);
379 	if (!ring_space)
380 		goto err_out_iounmap;
381 	ep->tx_ring = ring_space;
382 	ep->tx_ring_dma = ring_dma;
383 
384 	ring_space = dma_alloc_coherent(&pdev->dev, RX_TOTAL_SIZE, &ring_dma,
385 					GFP_KERNEL);
386 	if (!ring_space)
387 		goto err_out_unmap_tx;
388 	ep->rx_ring = ring_space;
389 	ep->rx_ring_dma = ring_dma;
390 
391 	if (dev->mem_start) {
392 		option = dev->mem_start;
393 		duplex = (dev->mem_start & 16) ? 1 : 0;
394 	} else if (card_idx >= 0  &&  card_idx < MAX_UNITS) {
395 		if (options[card_idx] >= 0)
396 			option = options[card_idx];
397 		if (full_duplex[card_idx] >= 0)
398 			duplex = full_duplex[card_idx];
399 	}
400 
401 	spin_lock_init(&ep->lock);
402 	spin_lock_init(&ep->napi_lock);
403 
404 	/* Bring the chip out of low-power mode. */
405 	ew32(GENCTL, 0x4200);
406 	/* Magic?!  If we don't set this bit the MII interface won't work. */
407 	/* This magic is documented in SMSC app note 7.15 */
408 	for (i = 16; i > 0; i--)
409 		ew32(TEST1, 0x0008);
410 
411 	/* Turn on the MII transceiver. */
412 	ew32(MIICfg, 0x12);
413 	if (chip_idx == 1)
414 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
415 	ew32(GENCTL, 0x0200);
416 
417 	/* Note: the '175 does not have a serial EEPROM. */
418 	for (i = 0; i < 3; i++)
419 		((__le16 *)dev->dev_addr)[i] = cpu_to_le16(er16(LAN0 + i*4));
420 
421 	if (debug > 2) {
422 		dev_dbg(&pdev->dev, "EEPROM contents:\n");
423 		for (i = 0; i < 64; i++)
424 			pr_cont(" %4.4x%s", read_eeprom(ep, i),
425 				   i % 16 == 15 ? "\n" : "");
426 	}
427 
428 	ep->pci_dev = pdev;
429 	ep->chip_id = chip_idx;
430 	ep->chip_flags = pci_id_tbl[chip_idx].drv_flags;
431 	ep->irq_mask =
432 		(ep->chip_flags & TYPE2_INTR ?  PCIBusErr175 : PCIBusErr170)
433 		 | CntFull | TxUnderrun | EpicNapiEvent;
434 
435 	/* Find the connected MII xcvrs.
436 	   Doing this in open() would allow detecting external xcvrs later, but
437 	   takes much time and no cards have external MII. */
438 	{
439 		int phy, phy_idx = 0;
440 		for (phy = 1; phy < 32 && phy_idx < sizeof(ep->phys); phy++) {
441 			int mii_status = mdio_read(dev, phy, MII_BMSR);
442 			if (mii_status != 0xffff  &&  mii_status != 0x0000) {
443 				ep->phys[phy_idx++] = phy;
444 				dev_info(&pdev->dev,
445 					"MII transceiver #%d control "
446 					"%4.4x status %4.4x.\n",
447 					phy, mdio_read(dev, phy, 0), mii_status);
448 			}
449 		}
450 		ep->mii_phy_cnt = phy_idx;
451 		if (phy_idx != 0) {
452 			phy = ep->phys[0];
453 			ep->mii.advertising = mdio_read(dev, phy, MII_ADVERTISE);
454 			dev_info(&pdev->dev,
455 				"Autonegotiation advertising %4.4x link "
456 				   "partner %4.4x.\n",
457 				   ep->mii.advertising, mdio_read(dev, phy, 5));
458 		} else if ( ! (ep->chip_flags & NO_MII)) {
459 			dev_warn(&pdev->dev,
460 				"***WARNING***: No MII transceiver found!\n");
461 			/* Use the known PHY address of the EPII. */
462 			ep->phys[0] = 3;
463 		}
464 		ep->mii.phy_id = ep->phys[0];
465 	}
466 
467 	/* Turn off the MII xcvr (175 only!), leave the chip in low-power mode. */
468 	if (ep->chip_flags & MII_PWRDWN)
469 		ew32(NVCTL, er32(NVCTL) & ~0x483c);
470 	ew32(GENCTL, 0x0008);
471 
472 	/* The lower four bits are the media type. */
473 	if (duplex) {
474 		ep->mii.force_media = ep->mii.full_duplex = 1;
475 		dev_info(&pdev->dev, "Forced full duplex requested.\n");
476 	}
477 	dev->if_port = ep->default_port = option;
478 
479 	/* The Epic-specific entries in the device structure. */
480 	dev->netdev_ops = &epic_netdev_ops;
481 	dev->ethtool_ops = &netdev_ethtool_ops;
482 	dev->watchdog_timeo = TX_TIMEOUT;
483 	netif_napi_add(dev, &ep->napi, epic_poll, 64);
484 
485 	ret = register_netdev(dev);
486 	if (ret < 0)
487 		goto err_out_unmap_rx;
488 
489 	netdev_info(dev, "%s at %lx, IRQ %d, %pM\n",
490 		    pci_id_tbl[chip_idx].name,
491 		    (long)pci_resource_start(pdev, EPIC_BAR), pdev->irq,
492 		    dev->dev_addr);
493 
494 out:
495 	return ret;
496 
497 err_out_unmap_rx:
498 	dma_free_coherent(&pdev->dev, RX_TOTAL_SIZE, ep->rx_ring,
499 			  ep->rx_ring_dma);
500 err_out_unmap_tx:
501 	dma_free_coherent(&pdev->dev, TX_TOTAL_SIZE, ep->tx_ring,
502 			  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 	timer_setup(&ep->timer, epic_timer, 0);
746 	ep->timer.expires = jiffies + 3*HZ;
747 	add_timer(&ep->timer);
748 
749 	return rc;
750 }
751 
752 /* Reset the chip to recover from a PCI transaction error.
753    This may occur at interrupt time. */
754 static void epic_pause(struct net_device *dev)
755 {
756 	struct net_device_stats *stats = &dev->stats;
757 	struct epic_private *ep = netdev_priv(dev);
758 	void __iomem *ioaddr = ep->ioaddr;
759 
760 	netif_stop_queue (dev);
761 
762 	/* Disable interrupts by clearing the interrupt mask. */
763 	ew32(INTMASK, 0x00000000);
764 	/* Stop the chip's Tx and Rx DMA processes. */
765 	ew16(COMMAND, StopRx | StopTxDMA | StopRxDMA);
766 
767 	/* Update the error counts. */
768 	if (er16(COMMAND) != 0xffff) {
769 		stats->rx_missed_errors	+= er8(MPCNT);
770 		stats->rx_frame_errors	+= er8(ALICNT);
771 		stats->rx_crc_errors	+= er8(CRCCNT);
772 	}
773 
774 	/* Remove the packets on the Rx queue. */
775 	epic_rx(dev, RX_RING_SIZE);
776 }
777 
778 static void epic_restart(struct net_device *dev)
779 {
780 	struct epic_private *ep = netdev_priv(dev);
781 	void __iomem *ioaddr = ep->ioaddr;
782 	int i;
783 
784 	/* Soft reset the chip. */
785 	ew32(GENCTL, 0x4001);
786 
787 	netdev_dbg(dev, "Restarting the EPIC chip, Rx %d/%d Tx %d/%d.\n",
788 		   ep->cur_rx, ep->dirty_rx, ep->dirty_tx, ep->cur_tx);
789 	udelay(1);
790 
791 	/* This magic is documented in SMSC app note 7.15 */
792 	for (i = 16; i > 0; i--)
793 		ew32(TEST1, 0x0008);
794 
795 #ifdef __BIG_ENDIAN
796 	ew32(GENCTL, 0x0432 | (RX_FIFO_THRESH << 8));
797 #else
798 	ew32(GENCTL, 0x0412 | (RX_FIFO_THRESH << 8));
799 #endif
800 	ew32(MIICfg, dev->if_port == 1 ? 0x13 : 0x12);
801 	if (ep->chip_flags & MII_PWRDWN)
802 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
803 
804 	for (i = 0; i < 3; i++)
805 		ew32(LAN0 + i*4, le16_to_cpu(((__le16*)dev->dev_addr)[i]));
806 
807 	ep->tx_threshold = TX_FIFO_THRESH;
808 	ew32(TxThresh, ep->tx_threshold);
809 	ew32(TxCtrl, ep->mii.full_duplex ? 0x7f : 0x79);
810 	ew32(PRxCDAR, ep->rx_ring_dma +
811 	     (ep->cur_rx % RX_RING_SIZE) * sizeof(struct epic_rx_desc));
812 	ew32(PTxCDAR, ep->tx_ring_dma +
813 	     (ep->dirty_tx % TX_RING_SIZE) * sizeof(struct epic_tx_desc));
814 
815 	/* Start the chip's Rx process. */
816 	set_rx_mode(dev);
817 	ew32(COMMAND, StartRx | RxQueued);
818 
819 	/* Enable interrupts by setting the interrupt mask. */
820 	ew32(INTMASK, RxError | RxHeader | EpicNapiEvent | CntFull |
821 	     ((ep->chip_flags & TYPE2_INTR) ? PCIBusErr175 : PCIBusErr170) |
822 	     TxUnderrun);
823 
824 	netdev_dbg(dev, "epic_restart() done, cmd status %4.4x, ctl %4.4x interrupt %4.4x.\n",
825 		   er32(COMMAND), er32(GENCTL), er32(INTSTAT));
826 }
827 
828 static void check_media(struct net_device *dev)
829 {
830 	struct epic_private *ep = netdev_priv(dev);
831 	void __iomem *ioaddr = ep->ioaddr;
832 	int mii_lpa = ep->mii_phy_cnt ? mdio_read(dev, ep->phys[0], MII_LPA) : 0;
833 	int negotiated = mii_lpa & ep->mii.advertising;
834 	int duplex = (negotiated & 0x0100) || (negotiated & 0x01C0) == 0x0040;
835 
836 	if (ep->mii.force_media)
837 		return;
838 	if (mii_lpa == 0xffff)		/* Bogus read */
839 		return;
840 	if (ep->mii.full_duplex != duplex) {
841 		ep->mii.full_duplex = duplex;
842 		netdev_info(dev, "Setting %s-duplex based on MII #%d link partner capability of %4.4x.\n",
843 			    ep->mii.full_duplex ? "full" : "half",
844 			    ep->phys[0], mii_lpa);
845 		ew32(TxCtrl, ep->mii.full_duplex ? 0x7F : 0x79);
846 	}
847 }
848 
849 static void epic_timer(struct timer_list *t)
850 {
851 	struct epic_private *ep = from_timer(ep, t, timer);
852 	struct net_device *dev = ep->mii.dev;
853 	void __iomem *ioaddr = ep->ioaddr;
854 	int next_tick = 5*HZ;
855 
856 	if (debug > 3) {
857 		netdev_dbg(dev, "Media monitor tick, Tx status %8.8x.\n",
858 			   er32(TxSTAT));
859 		netdev_dbg(dev, "Other registers are IntMask %4.4x IntStatus %4.4x RxStatus %4.4x.\n",
860 			   er32(INTMASK), er32(INTSTAT), er32(RxSTAT));
861 	}
862 
863 	check_media(dev);
864 
865 	ep->timer.expires = jiffies + next_tick;
866 	add_timer(&ep->timer);
867 }
868 
869 static void epic_tx_timeout(struct net_device *dev, unsigned int txqueue)
870 {
871 	struct epic_private *ep = netdev_priv(dev);
872 	void __iomem *ioaddr = ep->ioaddr;
873 
874 	if (debug > 0) {
875 		netdev_warn(dev, "Transmit timeout using MII device, Tx status %4.4x.\n",
876 			    er16(TxSTAT));
877 		if (debug > 1) {
878 			netdev_dbg(dev, "Tx indices: dirty_tx %d, cur_tx %d.\n",
879 				   ep->dirty_tx, ep->cur_tx);
880 		}
881 	}
882 	if (er16(TxSTAT) & 0x10) {		/* Tx FIFO underflow. */
883 		dev->stats.tx_fifo_errors++;
884 		ew32(COMMAND, RestartTx);
885 	} else {
886 		epic_restart(dev);
887 		ew32(COMMAND, TxQueued);
888 	}
889 
890 	netif_trans_update(dev); /* prevent tx timeout */
891 	dev->stats.tx_errors++;
892 	if (!ep->tx_full)
893 		netif_wake_queue(dev);
894 }
895 
896 /* Initialize the Rx and Tx rings, along with various 'dev' bits. */
897 static void epic_init_ring(struct net_device *dev)
898 {
899 	struct epic_private *ep = netdev_priv(dev);
900 	int i;
901 
902 	ep->tx_full = 0;
903 	ep->dirty_tx = ep->cur_tx = 0;
904 	ep->cur_rx = ep->dirty_rx = 0;
905 	ep->rx_buf_sz = (dev->mtu <= 1500 ? PKT_BUF_SZ : dev->mtu + 32);
906 
907 	/* Initialize all Rx descriptors. */
908 	for (i = 0; i < RX_RING_SIZE; i++) {
909 		ep->rx_ring[i].rxstatus = 0;
910 		ep->rx_ring[i].buflength = ep->rx_buf_sz;
911 		ep->rx_ring[i].next = ep->rx_ring_dma +
912 				      (i+1)*sizeof(struct epic_rx_desc);
913 		ep->rx_skbuff[i] = NULL;
914 	}
915 	/* Mark the last entry as wrapping the ring. */
916 	ep->rx_ring[i-1].next = ep->rx_ring_dma;
917 
918 	/* Fill in the Rx buffers.  Handle allocation failure gracefully. */
919 	for (i = 0; i < RX_RING_SIZE; i++) {
920 		struct sk_buff *skb = netdev_alloc_skb(dev, ep->rx_buf_sz + 2);
921 		ep->rx_skbuff[i] = skb;
922 		if (skb == NULL)
923 			break;
924 		skb_reserve(skb, 2);	/* 16 byte align the IP header. */
925 		ep->rx_ring[i].bufaddr = dma_map_single(&ep->pci_dev->dev,
926 							skb->data,
927 							ep->rx_buf_sz,
928 							DMA_FROM_DEVICE);
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 = dma_map_single(&ep->pci_dev->dev,
965 						    skb->data, skb->len,
966 						    DMA_TO_DEVICE);
967 	if (free_count < TX_QUEUE_LEN/2) {/* Typical path */
968 		ctrl_word = 0x100000; /* No interrupt */
969 	} else if (free_count == TX_QUEUE_LEN/2) {
970 		ctrl_word = 0x140000; /* Tx-done intr. */
971 	} else if (free_count < TX_QUEUE_LEN - 1) {
972 		ctrl_word = 0x100000; /* No Tx-done intr. */
973 	} else {
974 		/* Leave room for an additional entry. */
975 		ctrl_word = 0x140000; /* Tx-done intr. */
976 		ep->tx_full = 1;
977 	}
978 	ep->tx_ring[entry].buflength = ctrl_word | skb->len;
979 	ep->tx_ring[entry].txstatus =
980 		((skb->len >= ETH_ZLEN ? skb->len : ETH_ZLEN) << 16)
981 			    | DescOwn;
982 
983 	ep->cur_tx++;
984 	if (ep->tx_full)
985 		netif_stop_queue(dev);
986 
987 	spin_unlock_irqrestore(&ep->lock, flags);
988 	/* Trigger an immediate transmit demand. */
989 	ew32(COMMAND, TxQueued);
990 
991 	if (debug > 4)
992 		netdev_dbg(dev, "Queued Tx packet size %d to slot %d, flag %2.2x Tx status %8.8x.\n",
993 			   skb->len, entry, ctrl_word, er32(TxSTAT));
994 
995 	return NETDEV_TX_OK;
996 }
997 
998 static void epic_tx_error(struct net_device *dev, struct epic_private *ep,
999 			  int status)
1000 {
1001 	struct net_device_stats *stats = &dev->stats;
1002 
1003 #ifndef final_version
1004 	/* There was an major error, log it. */
1005 	if (debug > 1)
1006 		netdev_dbg(dev, "Transmit error, Tx status %8.8x.\n",
1007 			   status);
1008 #endif
1009 	stats->tx_errors++;
1010 	if (status & 0x1050)
1011 		stats->tx_aborted_errors++;
1012 	if (status & 0x0008)
1013 		stats->tx_carrier_errors++;
1014 	if (status & 0x0040)
1015 		stats->tx_window_errors++;
1016 	if (status & 0x0010)
1017 		stats->tx_fifo_errors++;
1018 }
1019 
1020 static void epic_tx(struct net_device *dev, struct epic_private *ep)
1021 {
1022 	unsigned int dirty_tx, cur_tx;
1023 
1024 	/*
1025 	 * Note: if this lock becomes a problem we can narrow the locked
1026 	 * region at the cost of occasionally grabbing the lock more times.
1027 	 */
1028 	cur_tx = ep->cur_tx;
1029 	for (dirty_tx = ep->dirty_tx; cur_tx - dirty_tx > 0; dirty_tx++) {
1030 		struct sk_buff *skb;
1031 		int entry = dirty_tx % TX_RING_SIZE;
1032 		int txstatus = ep->tx_ring[entry].txstatus;
1033 
1034 		if (txstatus & DescOwn)
1035 			break;	/* It still hasn't been Txed */
1036 
1037 		if (likely(txstatus & 0x0001)) {
1038 			dev->stats.collisions += (txstatus >> 8) & 15;
1039 			dev->stats.tx_packets++;
1040 			dev->stats.tx_bytes += ep->tx_skbuff[entry]->len;
1041 		} else
1042 			epic_tx_error(dev, ep, txstatus);
1043 
1044 		/* Free the original skb. */
1045 		skb = ep->tx_skbuff[entry];
1046 		dma_unmap_single(&ep->pci_dev->dev,
1047 				 ep->tx_ring[entry].bufaddr, skb->len,
1048 				 DMA_TO_DEVICE);
1049 		dev_consume_skb_irq(skb);
1050 		ep->tx_skbuff[entry] = NULL;
1051 	}
1052 
1053 #ifndef final_version
1054 	if (cur_tx - dirty_tx > TX_RING_SIZE) {
1055 		netdev_warn(dev, "Out-of-sync dirty pointer, %d vs. %d, full=%d.\n",
1056 			    dirty_tx, cur_tx, ep->tx_full);
1057 		dirty_tx += TX_RING_SIZE;
1058 	}
1059 #endif
1060 	ep->dirty_tx = dirty_tx;
1061 	if (ep->tx_full && cur_tx - dirty_tx < TX_QUEUE_LEN - 4) {
1062 		/* The ring is no longer full, allow new TX entries. */
1063 		ep->tx_full = 0;
1064 		netif_wake_queue(dev);
1065 	}
1066 }
1067 
1068 /* The interrupt handler does all of the Rx thread work and cleans up
1069    after the Tx thread. */
1070 static irqreturn_t epic_interrupt(int irq, void *dev_instance)
1071 {
1072 	struct net_device *dev = dev_instance;
1073 	struct epic_private *ep = netdev_priv(dev);
1074 	void __iomem *ioaddr = ep->ioaddr;
1075 	unsigned int handled = 0;
1076 	int status;
1077 
1078 	status = er32(INTSTAT);
1079 	/* Acknowledge all of the current interrupt sources ASAP. */
1080 	ew32(INTSTAT, status & EpicNormalEvent);
1081 
1082 	if (debug > 4) {
1083 		netdev_dbg(dev, "Interrupt, status=%#8.8x new intstat=%#8.8x.\n",
1084 			   status, er32(INTSTAT));
1085 	}
1086 
1087 	if ((status & IntrSummary) == 0)
1088 		goto out;
1089 
1090 	handled = 1;
1091 
1092 	if (status & EpicNapiEvent) {
1093 		spin_lock(&ep->napi_lock);
1094 		if (napi_schedule_prep(&ep->napi)) {
1095 			epic_napi_irq_off(dev, ep);
1096 			__napi_schedule(&ep->napi);
1097 		}
1098 		spin_unlock(&ep->napi_lock);
1099 	}
1100 	status &= ~EpicNapiEvent;
1101 
1102 	/* Check uncommon events all at once. */
1103 	if (status & (CntFull | TxUnderrun | PCIBusErr170 | PCIBusErr175)) {
1104 		struct net_device_stats *stats = &dev->stats;
1105 
1106 		if (status == EpicRemoved)
1107 			goto out;
1108 
1109 		/* Always update the error counts to avoid overhead later. */
1110 		stats->rx_missed_errors	+= er8(MPCNT);
1111 		stats->rx_frame_errors	+= er8(ALICNT);
1112 		stats->rx_crc_errors	+= er8(CRCCNT);
1113 
1114 		if (status & TxUnderrun) { /* Tx FIFO underflow. */
1115 			stats->tx_fifo_errors++;
1116 			ew32(TxThresh, ep->tx_threshold += 128);
1117 			/* Restart the transmit process. */
1118 			ew32(COMMAND, RestartTx);
1119 		}
1120 		if (status & PCIBusErr170) {
1121 			netdev_err(dev, "PCI Bus Error! status %4.4x.\n",
1122 				   status);
1123 			epic_pause(dev);
1124 			epic_restart(dev);
1125 		}
1126 		/* Clear all error sources. */
1127 		ew32(INTSTAT, status & 0x7f18);
1128 	}
1129 
1130 out:
1131 	if (debug > 3) {
1132 		netdev_dbg(dev, "exit interrupt, intr_status=%#4.4x.\n",
1133 			   status);
1134 	}
1135 
1136 	return IRQ_RETVAL(handled);
1137 }
1138 
1139 static int epic_rx(struct net_device *dev, int budget)
1140 {
1141 	struct epic_private *ep = netdev_priv(dev);
1142 	int entry = ep->cur_rx % RX_RING_SIZE;
1143 	int rx_work_limit = ep->dirty_rx + RX_RING_SIZE - ep->cur_rx;
1144 	int work_done = 0;
1145 
1146 	if (debug > 4)
1147 		netdev_dbg(dev, " In epic_rx(), entry %d %8.8x.\n", entry,
1148 			   ep->rx_ring[entry].rxstatus);
1149 
1150 	if (rx_work_limit > budget)
1151 		rx_work_limit = budget;
1152 
1153 	/* If we own the next entry, it's a new packet. Send it up. */
1154 	while ((ep->rx_ring[entry].rxstatus & DescOwn) == 0) {
1155 		int status = ep->rx_ring[entry].rxstatus;
1156 
1157 		if (debug > 4)
1158 			netdev_dbg(dev, "  epic_rx() status was %8.8x.\n",
1159 				   status);
1160 		if (--rx_work_limit < 0)
1161 			break;
1162 		if (status & 0x2006) {
1163 			if (debug > 2)
1164 				netdev_dbg(dev, "epic_rx() error status was %8.8x.\n",
1165 					   status);
1166 			if (status & 0x2000) {
1167 				netdev_warn(dev, "Oversized Ethernet frame spanned multiple buffers, status %4.4x!\n",
1168 					    status);
1169 				dev->stats.rx_length_errors++;
1170 			} else if (status & 0x0006)
1171 				/* Rx Frame errors are counted in hardware. */
1172 				dev->stats.rx_errors++;
1173 		} else {
1174 			/* Malloc up new buffer, compatible with net-2e. */
1175 			/* Omit the four octet CRC from the length. */
1176 			short pkt_len = (status >> 16) - 4;
1177 			struct sk_buff *skb;
1178 
1179 			if (pkt_len > PKT_BUF_SZ - 4) {
1180 				netdev_err(dev, "Oversized Ethernet frame, status %x %d bytes.\n",
1181 					   status, pkt_len);
1182 				pkt_len = 1514;
1183 			}
1184 			/* Check if the packet is long enough to accept without copying
1185 			   to a minimally-sized skbuff. */
1186 			if (pkt_len < rx_copybreak &&
1187 			    (skb = netdev_alloc_skb(dev, pkt_len + 2)) != NULL) {
1188 				skb_reserve(skb, 2);	/* 16 byte align the IP header */
1189 				dma_sync_single_for_cpu(&ep->pci_dev->dev,
1190 							ep->rx_ring[entry].bufaddr,
1191 							ep->rx_buf_sz,
1192 							DMA_FROM_DEVICE);
1193 				skb_copy_to_linear_data(skb, ep->rx_skbuff[entry]->data, pkt_len);
1194 				skb_put(skb, pkt_len);
1195 				dma_sync_single_for_device(&ep->pci_dev->dev,
1196 							   ep->rx_ring[entry].bufaddr,
1197 							   ep->rx_buf_sz,
1198 							   DMA_FROM_DEVICE);
1199 			} else {
1200 				dma_unmap_single(&ep->pci_dev->dev,
1201 						 ep->rx_ring[entry].bufaddr,
1202 						 ep->rx_buf_sz,
1203 						 DMA_FROM_DEVICE);
1204 				skb_put(skb = ep->rx_skbuff[entry], pkt_len);
1205 				ep->rx_skbuff[entry] = NULL;
1206 			}
1207 			skb->protocol = eth_type_trans(skb, dev);
1208 			netif_receive_skb(skb);
1209 			dev->stats.rx_packets++;
1210 			dev->stats.rx_bytes += pkt_len;
1211 		}
1212 		work_done++;
1213 		entry = (++ep->cur_rx) % RX_RING_SIZE;
1214 	}
1215 
1216 	/* Refill the Rx ring buffers. */
1217 	for (; ep->cur_rx - ep->dirty_rx > 0; ep->dirty_rx++) {
1218 		entry = ep->dirty_rx % RX_RING_SIZE;
1219 		if (ep->rx_skbuff[entry] == NULL) {
1220 			struct sk_buff *skb;
1221 			skb = ep->rx_skbuff[entry] = netdev_alloc_skb(dev, ep->rx_buf_sz + 2);
1222 			if (skb == NULL)
1223 				break;
1224 			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
1225 			ep->rx_ring[entry].bufaddr = dma_map_single(&ep->pci_dev->dev,
1226 								    skb->data,
1227 								    ep->rx_buf_sz,
1228 								    DMA_FROM_DEVICE);
1229 			work_done++;
1230 		}
1231 		/* AV: shouldn't we add a barrier here? */
1232 		ep->rx_ring[entry].rxstatus = DescOwn;
1233 	}
1234 	return work_done;
1235 }
1236 
1237 static void epic_rx_err(struct net_device *dev, struct epic_private *ep)
1238 {
1239 	void __iomem *ioaddr = ep->ioaddr;
1240 	int status;
1241 
1242 	status = er32(INTSTAT);
1243 
1244 	if (status == EpicRemoved)
1245 		return;
1246 	if (status & RxOverflow) 	/* Missed a Rx frame. */
1247 		dev->stats.rx_errors++;
1248 	if (status & (RxOverflow | RxFull))
1249 		ew16(COMMAND, RxQueued);
1250 }
1251 
1252 static int epic_poll(struct napi_struct *napi, int budget)
1253 {
1254 	struct epic_private *ep = container_of(napi, struct epic_private, napi);
1255 	struct net_device *dev = ep->mii.dev;
1256 	void __iomem *ioaddr = ep->ioaddr;
1257 	int work_done;
1258 
1259 	epic_tx(dev, ep);
1260 
1261 	work_done = epic_rx(dev, budget);
1262 
1263 	epic_rx_err(dev, ep);
1264 
1265 	if (work_done < budget && napi_complete_done(napi, work_done)) {
1266 		unsigned long flags;
1267 
1268 		spin_lock_irqsave(&ep->napi_lock, flags);
1269 
1270 		ew32(INTSTAT, EpicNapiEvent);
1271 		epic_napi_irq_on(dev, ep);
1272 		spin_unlock_irqrestore(&ep->napi_lock, flags);
1273 	}
1274 
1275 	return work_done;
1276 }
1277 
1278 static int epic_close(struct net_device *dev)
1279 {
1280 	struct epic_private *ep = netdev_priv(dev);
1281 	struct pci_dev *pdev = ep->pci_dev;
1282 	void __iomem *ioaddr = ep->ioaddr;
1283 	struct sk_buff *skb;
1284 	int i;
1285 
1286 	netif_stop_queue(dev);
1287 	napi_disable(&ep->napi);
1288 
1289 	if (debug > 1)
1290 		netdev_dbg(dev, "Shutting down ethercard, status was %2.2x.\n",
1291 			   er32(INTSTAT));
1292 
1293 	del_timer_sync(&ep->timer);
1294 
1295 	epic_disable_int(dev, ep);
1296 
1297 	free_irq(pdev->irq, dev);
1298 
1299 	epic_pause(dev);
1300 
1301 	/* Free all the skbuffs in the Rx queue. */
1302 	for (i = 0; i < RX_RING_SIZE; i++) {
1303 		skb = ep->rx_skbuff[i];
1304 		ep->rx_skbuff[i] = NULL;
1305 		ep->rx_ring[i].rxstatus = 0;		/* Not owned by Epic chip. */
1306 		ep->rx_ring[i].buflength = 0;
1307 		if (skb) {
1308 			dma_unmap_single(&pdev->dev, ep->rx_ring[i].bufaddr,
1309 					 ep->rx_buf_sz, DMA_FROM_DEVICE);
1310 			dev_kfree_skb(skb);
1311 		}
1312 		ep->rx_ring[i].bufaddr = 0xBADF00D0; /* An invalid address. */
1313 	}
1314 	for (i = 0; i < TX_RING_SIZE; i++) {
1315 		skb = ep->tx_skbuff[i];
1316 		ep->tx_skbuff[i] = NULL;
1317 		if (!skb)
1318 			continue;
1319 		dma_unmap_single(&pdev->dev, ep->tx_ring[i].bufaddr, skb->len,
1320 				 DMA_TO_DEVICE);
1321 		dev_kfree_skb(skb);
1322 	}
1323 
1324 	/* Green! Leave the chip in low-power mode. */
1325 	ew32(GENCTL, 0x0008);
1326 
1327 	return 0;
1328 }
1329 
1330 static struct net_device_stats *epic_get_stats(struct net_device *dev)
1331 {
1332 	struct epic_private *ep = netdev_priv(dev);
1333 	void __iomem *ioaddr = ep->ioaddr;
1334 
1335 	if (netif_running(dev)) {
1336 		struct net_device_stats *stats = &dev->stats;
1337 
1338 		stats->rx_missed_errors	+= er8(MPCNT);
1339 		stats->rx_frame_errors	+= er8(ALICNT);
1340 		stats->rx_crc_errors	+= er8(CRCCNT);
1341 	}
1342 
1343 	return &dev->stats;
1344 }
1345 
1346 /* Set or clear the multicast filter for this adaptor.
1347    Note that we only use exclusion around actually queueing the
1348    new frame, not around filling ep->setup_frame.  This is non-deterministic
1349    when re-entered but still correct. */
1350 
1351 static void set_rx_mode(struct net_device *dev)
1352 {
1353 	struct epic_private *ep = netdev_priv(dev);
1354 	void __iomem *ioaddr = ep->ioaddr;
1355 	unsigned char mc_filter[8];		 /* Multicast hash filter */
1356 	int i;
1357 
1358 	if (dev->flags & IFF_PROMISC) {			/* Set promiscuous. */
1359 		ew32(RxCtrl, 0x002c);
1360 		/* Unconditionally log net taps. */
1361 		memset(mc_filter, 0xff, sizeof(mc_filter));
1362 	} else if ((!netdev_mc_empty(dev)) || (dev->flags & IFF_ALLMULTI)) {
1363 		/* There is apparently a chip bug, so the multicast filter
1364 		   is never enabled. */
1365 		/* Too many to filter perfectly -- accept all multicasts. */
1366 		memset(mc_filter, 0xff, sizeof(mc_filter));
1367 		ew32(RxCtrl, 0x000c);
1368 	} else if (netdev_mc_empty(dev)) {
1369 		ew32(RxCtrl, 0x0004);
1370 		return;
1371 	} else {					/* Never executed, for now. */
1372 		struct netdev_hw_addr *ha;
1373 
1374 		memset(mc_filter, 0, sizeof(mc_filter));
1375 		netdev_for_each_mc_addr(ha, dev) {
1376 			unsigned int bit_nr =
1377 				ether_crc_le(ETH_ALEN, ha->addr) & 0x3f;
1378 			mc_filter[bit_nr >> 3] |= (1 << bit_nr);
1379 		}
1380 	}
1381 	/* ToDo: perhaps we need to stop the Tx and Rx process here? */
1382 	if (memcmp(mc_filter, ep->mc_filter, sizeof(mc_filter))) {
1383 		for (i = 0; i < 4; i++)
1384 			ew16(MC0 + i*4, ((u16 *)mc_filter)[i]);
1385 		memcpy(ep->mc_filter, mc_filter, sizeof(mc_filter));
1386 	}
1387 }
1388 
1389 static void netdev_get_drvinfo (struct net_device *dev, struct ethtool_drvinfo *info)
1390 {
1391 	struct epic_private *np = netdev_priv(dev);
1392 
1393 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
1394 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
1395 	strlcpy(info->bus_info, pci_name(np->pci_dev), sizeof(info->bus_info));
1396 }
1397 
1398 static int netdev_get_link_ksettings(struct net_device *dev,
1399 				     struct ethtool_link_ksettings *cmd)
1400 {
1401 	struct epic_private *np = netdev_priv(dev);
1402 
1403 	spin_lock_irq(&np->lock);
1404 	mii_ethtool_get_link_ksettings(&np->mii, cmd);
1405 	spin_unlock_irq(&np->lock);
1406 
1407 	return 0;
1408 }
1409 
1410 static int netdev_set_link_ksettings(struct net_device *dev,
1411 				     const struct ethtool_link_ksettings *cmd)
1412 {
1413 	struct epic_private *np = netdev_priv(dev);
1414 	int rc;
1415 
1416 	spin_lock_irq(&np->lock);
1417 	rc = mii_ethtool_set_link_ksettings(&np->mii, cmd);
1418 	spin_unlock_irq(&np->lock);
1419 
1420 	return rc;
1421 }
1422 
1423 static int netdev_nway_reset(struct net_device *dev)
1424 {
1425 	struct epic_private *np = netdev_priv(dev);
1426 	return mii_nway_restart(&np->mii);
1427 }
1428 
1429 static u32 netdev_get_link(struct net_device *dev)
1430 {
1431 	struct epic_private *np = netdev_priv(dev);
1432 	return mii_link_ok(&np->mii);
1433 }
1434 
1435 static u32 netdev_get_msglevel(struct net_device *dev)
1436 {
1437 	return debug;
1438 }
1439 
1440 static void netdev_set_msglevel(struct net_device *dev, u32 value)
1441 {
1442 	debug = value;
1443 }
1444 
1445 static int ethtool_begin(struct net_device *dev)
1446 {
1447 	struct epic_private *ep = netdev_priv(dev);
1448 	void __iomem *ioaddr = ep->ioaddr;
1449 
1450 	if (ep->ethtool_ops_nesting == U32_MAX)
1451 		return -EBUSY;
1452 	/* power-up, if interface is down */
1453 	if (!ep->ethtool_ops_nesting++ && !netif_running(dev)) {
1454 		ew32(GENCTL, 0x0200);
1455 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
1456 	}
1457 	return 0;
1458 }
1459 
1460 static void ethtool_complete(struct net_device *dev)
1461 {
1462 	struct epic_private *ep = netdev_priv(dev);
1463 	void __iomem *ioaddr = ep->ioaddr;
1464 
1465 	/* power-down, if interface is down */
1466 	if (!--ep->ethtool_ops_nesting && !netif_running(dev)) {
1467 		ew32(GENCTL, 0x0008);
1468 		ew32(NVCTL, (er32(NVCTL) & ~0x483c) | 0x0000);
1469 	}
1470 }
1471 
1472 static const struct ethtool_ops netdev_ethtool_ops = {
1473 	.get_drvinfo		= netdev_get_drvinfo,
1474 	.nway_reset		= netdev_nway_reset,
1475 	.get_link		= netdev_get_link,
1476 	.get_msglevel		= netdev_get_msglevel,
1477 	.set_msglevel		= netdev_set_msglevel,
1478 	.begin			= ethtool_begin,
1479 	.complete		= ethtool_complete,
1480 	.get_link_ksettings	= netdev_get_link_ksettings,
1481 	.set_link_ksettings	= netdev_set_link_ksettings,
1482 };
1483 
1484 static int netdev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1485 {
1486 	struct epic_private *np = netdev_priv(dev);
1487 	void __iomem *ioaddr = np->ioaddr;
1488 	struct mii_ioctl_data *data = if_mii(rq);
1489 	int rc;
1490 
1491 	/* power-up, if interface is down */
1492 	if (! netif_running(dev)) {
1493 		ew32(GENCTL, 0x0200);
1494 		ew32(NVCTL, (er32(NVCTL) & ~0x003c) | 0x4800);
1495 	}
1496 
1497 	/* all non-ethtool ioctls (the SIOC[GS]MIIxxx ioctls) */
1498 	spin_lock_irq(&np->lock);
1499 	rc = generic_mii_ioctl(&np->mii, data, cmd, NULL);
1500 	spin_unlock_irq(&np->lock);
1501 
1502 	/* power-down, if interface is down */
1503 	if (! netif_running(dev)) {
1504 		ew32(GENCTL, 0x0008);
1505 		ew32(NVCTL, (er32(NVCTL) & ~0x483c) | 0x0000);
1506 	}
1507 	return rc;
1508 }
1509 
1510 
1511 static void epic_remove_one(struct pci_dev *pdev)
1512 {
1513 	struct net_device *dev = pci_get_drvdata(pdev);
1514 	struct epic_private *ep = netdev_priv(dev);
1515 
1516 	dma_free_coherent(&pdev->dev, TX_TOTAL_SIZE, ep->tx_ring,
1517 			  ep->tx_ring_dma);
1518 	dma_free_coherent(&pdev->dev, RX_TOTAL_SIZE, ep->rx_ring,
1519 			  ep->rx_ring_dma);
1520 	unregister_netdev(dev);
1521 	pci_iounmap(pdev, ep->ioaddr);
1522 	pci_release_regions(pdev);
1523 	free_netdev(dev);
1524 	pci_disable_device(pdev);
1525 	/* pci_power_off(pdev, -1); */
1526 }
1527 
1528 static int __maybe_unused epic_suspend(struct device *dev_d)
1529 {
1530 	struct net_device *dev = dev_get_drvdata(dev_d);
1531 	struct epic_private *ep = netdev_priv(dev);
1532 	void __iomem *ioaddr = ep->ioaddr;
1533 
1534 	if (!netif_running(dev))
1535 		return 0;
1536 	epic_pause(dev);
1537 	/* Put the chip into low-power mode. */
1538 	ew32(GENCTL, 0x0008);
1539 	/* pci_power_off(pdev, -1); */
1540 	return 0;
1541 }
1542 
1543 
1544 static int __maybe_unused epic_resume(struct device *dev_d)
1545 {
1546 	struct net_device *dev = dev_get_drvdata(dev_d);
1547 
1548 	if (!netif_running(dev))
1549 		return 0;
1550 	epic_restart(dev);
1551 	/* pci_power_on(pdev); */
1552 	return 0;
1553 }
1554 
1555 static SIMPLE_DEV_PM_OPS(epic_pm_ops, epic_suspend, epic_resume);
1556 
1557 static struct pci_driver epic_driver = {
1558 	.name		= DRV_NAME,
1559 	.id_table	= epic_pci_tbl,
1560 	.probe		= epic_init_one,
1561 	.remove		= epic_remove_one,
1562 	.driver.pm	= &epic_pm_ops,
1563 };
1564 
1565 
1566 static int __init epic_init (void)
1567 {
1568 /* when a module, this is printed whether or not devices are found in probe */
1569 #ifdef MODULE
1570 	pr_info("%s%s\n", version, version2);
1571 #endif
1572 
1573 	return pci_register_driver(&epic_driver);
1574 }
1575 
1576 
1577 static void __exit epic_cleanup (void)
1578 {
1579 	pci_unregister_driver (&epic_driver);
1580 }
1581 
1582 
1583 module_init(epic_init);
1584 module_exit(epic_cleanup);
1585