xref: /openbmc/u-boot/drivers/net/natsemi.c (revision c83c436d)
1 /*
2    natsemi.c: A U-Boot driver for the NatSemi DP8381x series.
3    Author: Mark A. Rakes (mark_rakes@vivato.net)
4 
5    Adapted from an Etherboot driver written by:
6 
7    Copyright (C) 2001 Entity Cyber, Inc.
8 
9    This development of this Etherboot driver was funded by
10 
11       Sicom Systems: http://www.sicompos.com/
12 
13    Author: Marty Connor (mdc@thinguin.org)
14    Adapted from a Linux driver which was written by Donald Becker
15 
16    This software may be used and distributed according to the terms
17    of the GNU Public License (GPL), incorporated herein by reference.
18 
19    Original Copyright Notice:
20 
21    Written/copyright 1999-2001 by Donald Becker.
22 
23    This software may be used and distributed according to the terms of
24    the GNU General Public License (GPL), incorporated herein by reference.
25    Drivers based on or derived from this code fall under the GPL and must
26    retain the authorship, copyright and license notice.  This file is not
27    a complete program and may only be used when the entire operating
28    system is licensed under the GPL.  License for under other terms may be
29    available.  Contact the original author for details.
30 
31    The original author may be reached as becker@scyld.com, or at
32    Scyld Computing Corporation
33    410 Severn Ave., Suite 210
34    Annapolis MD 21403
35 
36    Support information and updates available at
37    http://www.scyld.com/network/netsemi.html
38 
39    References:
40    http://www.scyld.com/expert/100mbps.html
41    http://www.scyld.com/expert/NWay.html
42    Datasheet is available from:
43    http://www.national.com/pf/DP/DP83815.html
44 */
45 
46 /* Revision History
47  * October 2002 mar	1.0
48  *   Initial U-Boot Release.  Tested with Netgear FA311 board
49  *   and dp83815 chipset on custom board
50 */
51 
52 /* Includes */
53 #include <common.h>
54 #include <malloc.h>
55 #include <net.h>
56 #include <netdev.h>
57 #include <asm/io.h>
58 #include <pci.h>
59 
60 /* defines */
61 #define EEPROM_SIZE 0xb /*12 16-bit chunks, or 24 bytes*/
62 
63 #define DSIZE		0x00000FFF
64 #define CRC_SIZE	4
65 #define TOUT_LOOP	500000
66 #define TX_BUF_SIZE	1536
67 #define RX_BUF_SIZE	1536
68 #define NUM_RX_DESC	4	/* Number of Rx descriptor registers. */
69 
70 /* Offsets to the device registers.
71    Unlike software-only systems, device drivers interact with complex hardware.
72    It's not useful to define symbolic names for every register bit in the
73    device.  */
74 enum register_offsets {
75 	ChipCmd	= 0x00,
76 	ChipConfig	= 0x04,
77 	EECtrl		= 0x08,
78 	IntrMask	= 0x14,
79 	IntrEnable	= 0x18,
80 	TxRingPtr	= 0x20,
81 	TxConfig	= 0x24,
82 	RxRingPtr	= 0x30,
83 	RxConfig	= 0x34,
84 	ClkRun		= 0x3C,
85 	RxFilterAddr	= 0x48,
86 	RxFilterData	= 0x4C,
87 	SiliconRev	= 0x58,
88 	PCIPM		= 0x44,
89 	BasicControl	= 0x80,
90 	BasicStatus	= 0x84,
91 	/* These are from the spec, around page 78... on a separate table. */
92 	PGSEL		= 0xCC,
93 	PMDCSR		= 0xE4,
94 	TSTDAT		= 0xFC,
95 	DSPCFG		= 0xF4,
96 	SDCFG		= 0x8C
97 };
98 
99 /* Bit in ChipCmd. */
100 enum ChipCmdBits {
101 	ChipReset	= 0x100,
102 	RxReset		= 0x20,
103 	TxReset		= 0x10,
104 	RxOff		= 0x08,
105 	RxOn		= 0x04,
106 	TxOff		= 0x02,
107 	TxOn		= 0x01
108 };
109 
110 enum ChipConfigBits {
111 	LinkSts	= 0x80000000,
112 	HundSpeed	= 0x40000000,
113 	FullDuplex	= 0x20000000,
114 	TenPolarity	= 0x10000000,
115 	AnegDone	= 0x08000000,
116 	AnegEnBothBoth	= 0x0000E000,
117 	AnegDis100Full	= 0x0000C000,
118 	AnegEn100Both	= 0x0000A000,
119 	AnegDis100Half	= 0x00008000,
120 	AnegEnBothHalf	= 0x00006000,
121 	AnegDis10Full	= 0x00004000,
122 	AnegEn10Both	= 0x00002000,
123 	DuplexMask	= 0x00008000,
124 	SpeedMask	= 0x00004000,
125 	AnegMask	= 0x00002000,
126 	AnegDis10Half	= 0x00000000,
127 	ExtPhy		= 0x00001000,
128 	PhyRst		= 0x00000400,
129 	PhyDis		= 0x00000200,
130 	BootRomDisable	= 0x00000004,
131 	BEMode		= 0x00000001,
132 };
133 
134 enum TxConfig_bits {
135 	TxDrthMask	= 0x3f,
136 	TxFlthMask	= 0x3f00,
137 	TxMxdmaMask	= 0x700000,
138 	TxMxdma_512	= 0x0,
139 	TxMxdma_4	= 0x100000,
140 	TxMxdma_8	= 0x200000,
141 	TxMxdma_16	= 0x300000,
142 	TxMxdma_32	= 0x400000,
143 	TxMxdma_64	= 0x500000,
144 	TxMxdma_128	= 0x600000,
145 	TxMxdma_256	= 0x700000,
146 	TxCollRetry	= 0x800000,
147 	TxAutoPad	= 0x10000000,
148 	TxMacLoop	= 0x20000000,
149 	TxHeartIgn	= 0x40000000,
150 	TxCarrierIgn	= 0x80000000
151 };
152 
153 enum RxConfig_bits {
154 	RxDrthMask	= 0x3e,
155 	RxMxdmaMask	= 0x700000,
156 	RxMxdma_512	= 0x0,
157 	RxMxdma_4	= 0x100000,
158 	RxMxdma_8	= 0x200000,
159 	RxMxdma_16	= 0x300000,
160 	RxMxdma_32	= 0x400000,
161 	RxMxdma_64	= 0x500000,
162 	RxMxdma_128	= 0x600000,
163 	RxMxdma_256	= 0x700000,
164 	RxAcceptLong	= 0x8000000,
165 	RxAcceptTx	= 0x10000000,
166 	RxAcceptRunt	= 0x40000000,
167 	RxAcceptErr	= 0x80000000
168 };
169 
170 /* Bits in the RxMode register. */
171 enum rx_mode_bits {
172 	AcceptErr	= 0x20,
173 	AcceptRunt	= 0x10,
174 	AcceptBroadcast	= 0xC0000000,
175 	AcceptMulticast	= 0x00200000,
176 	AcceptAllMulticast = 0x20000000,
177 	AcceptAllPhys	= 0x10000000,
178 	AcceptMyPhys	= 0x08000000
179 };
180 
181 typedef struct _BufferDesc {
182 	u32 link;
183 	vu_long cmdsts;
184 	u32 bufptr;
185 	u32 software_use;
186 } BufferDesc;
187 
188 /* Bits in network_desc.status */
189 enum desc_status_bits {
190 	DescOwn = 0x80000000, DescMore = 0x40000000, DescIntr = 0x20000000,
191 	DescNoCRC = 0x10000000, DescPktOK = 0x08000000,
192 	DescSizeMask = 0xfff,
193 
194 	DescTxAbort = 0x04000000, DescTxFIFO = 0x02000000,
195 	DescTxCarrier = 0x01000000, DescTxDefer = 0x00800000,
196 	DescTxExcDefer = 0x00400000, DescTxOOWCol = 0x00200000,
197 	DescTxExcColl = 0x00100000, DescTxCollCount = 0x000f0000,
198 
199 	DescRxAbort = 0x04000000, DescRxOver = 0x02000000,
200 	DescRxDest = 0x01800000, DescRxLong = 0x00400000,
201 	DescRxRunt = 0x00200000, DescRxInvalid = 0x00100000,
202 	DescRxCRC = 0x00080000, DescRxAlign = 0x00040000,
203 	DescRxLoop = 0x00020000, DesRxColl = 0x00010000,
204 };
205 
206 /* Globals */
207 #ifdef NATSEMI_DEBUG
208 static int natsemi_debug = 0;	/* 1 verbose debugging, 0 normal */
209 #endif
210 static u32 SavedClkRun;
211 static unsigned int cur_rx;
212 static unsigned int advertising;
213 static unsigned int rx_config;
214 static unsigned int tx_config;
215 
216 /* Note: transmit and receive buffers and descriptors must be
217    longword aligned */
218 static BufferDesc txd __attribute__ ((aligned(4)));
219 static BufferDesc rxd[NUM_RX_DESC] __attribute__ ((aligned(4)));
220 
221 static unsigned char txb[TX_BUF_SIZE] __attribute__ ((aligned(4)));
222 static unsigned char rxb[NUM_RX_DESC * RX_BUF_SIZE]
223     __attribute__ ((aligned(4)));
224 
225 /* Function Prototypes */
226 #if 0
227 static void write_eeprom(struct eth_device *dev, long addr, int location,
228 			 short value);
229 #endif
230 static int read_eeprom(struct eth_device *dev, long addr, int location);
231 static int mdio_read(struct eth_device *dev, int phy_id, int location);
232 static int natsemi_init(struct eth_device *dev, bd_t * bis);
233 static void natsemi_reset(struct eth_device *dev);
234 static void natsemi_init_rxfilter(struct eth_device *dev);
235 static void natsemi_init_txd(struct eth_device *dev);
236 static void natsemi_init_rxd(struct eth_device *dev);
237 static void natsemi_set_rx_mode(struct eth_device *dev);
238 static void natsemi_check_duplex(struct eth_device *dev);
239 static int natsemi_send(struct eth_device *dev, void *packet, int length);
240 static int natsemi_poll(struct eth_device *dev);
241 static void natsemi_disable(struct eth_device *dev);
242 
243 static struct pci_device_id supported[] = {
244 	{PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_83815},
245 	{}
246 };
247 
248 #define bus_to_phys(a)	pci_mem_to_phys((pci_dev_t)dev->priv, a)
249 #define phys_to_bus(a)	pci_phys_to_mem((pci_dev_t)dev->priv, a)
250 
251 static inline int
252 INW(struct eth_device *dev, u_long addr)
253 {
254 	return le16_to_cpu(*(vu_short *) (addr + dev->iobase));
255 }
256 
257 static int
258 INL(struct eth_device *dev, u_long addr)
259 {
260 	return le32_to_cpu(*(vu_long *) (addr + dev->iobase));
261 }
262 
263 static inline void
264 OUTW(struct eth_device *dev, int command, u_long addr)
265 {
266 	*(vu_short *) ((addr + dev->iobase)) = cpu_to_le16(command);
267 }
268 
269 static inline void
270 OUTL(struct eth_device *dev, int command, u_long addr)
271 {
272 	*(vu_long *) ((addr + dev->iobase)) = cpu_to_le32(command);
273 }
274 
275 /*
276  * Function: natsemi_initialize
277  *
278  * Description: Retrieves the MAC address of the card, and sets up some
279  * globals required by other routines,  and initializes the NIC, making it
280  * ready to send and receive packets.
281  *
282  * Side effects:
283  *            leaves the natsemi initialized, and ready to receive packets.
284  *
285  * Returns:   struct eth_device *:          pointer to NIC data structure
286  */
287 
288 int
289 natsemi_initialize(bd_t * bis)
290 {
291 	pci_dev_t devno;
292 	int card_number = 0;
293 	struct eth_device *dev;
294 	u32 iobase, status, chip_config;
295 	int i, idx = 0;
296 	int prev_eedata;
297 	u32 tmp;
298 
299 	while (1) {
300 		/* Find PCI device(s) */
301 		if ((devno = pci_find_devices(supported, idx++)) < 0) {
302 			break;
303 		}
304 
305 		pci_read_config_dword(devno, PCI_BASE_ADDRESS_0, &iobase);
306 		iobase &= ~0x3;	/* bit 1: unused and bit 0: I/O Space Indicator */
307 
308 		pci_write_config_dword(devno, PCI_COMMAND,
309 				       PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
310 
311 		/* Check if I/O accesses and Bus Mastering are enabled. */
312 		pci_read_config_dword(devno, PCI_COMMAND, &status);
313 		if (!(status & PCI_COMMAND_MEMORY)) {
314 			printf("Error: Can not enable MEM access.\n");
315 			continue;
316 		} else if (!(status & PCI_COMMAND_MASTER)) {
317 			printf("Error: Can not enable Bus Mastering.\n");
318 			continue;
319 		}
320 
321 		dev = (struct eth_device *) malloc(sizeof *dev);
322 		if (!dev) {
323 			printf("natsemi: Can not allocate memory\n");
324 			break;
325 		}
326 		memset(dev, 0, sizeof(*dev));
327 
328 		sprintf(dev->name, "dp83815#%d", card_number);
329 		dev->iobase = bus_to_phys(iobase);
330 #ifdef NATSEMI_DEBUG
331 		printf("natsemi: NatSemi ns8381[56] @ %#x\n", dev->iobase);
332 #endif
333 		dev->priv = (void *) devno;
334 		dev->init = natsemi_init;
335 		dev->halt = natsemi_disable;
336 		dev->send = natsemi_send;
337 		dev->recv = natsemi_poll;
338 
339 		eth_register(dev);
340 
341 		card_number++;
342 
343 		/* Set the latency timer for value. */
344 		pci_write_config_byte(devno, PCI_LATENCY_TIMER, 0x20);
345 
346 		udelay(10 * 1000);
347 
348 		/* natsemi has a non-standard PM control register
349 		 * in PCI config space.  Some boards apparently need
350 		 * to be brought to D0 in this manner.  */
351 		pci_read_config_dword(devno, PCIPM, &tmp);
352 		if (tmp & (0x03 | 0x100)) {
353 			/* D0 state, disable PME assertion */
354 			u32 newtmp = tmp & ~(0x03 | 0x100);
355 			pci_write_config_dword(devno, PCIPM, newtmp);
356 		}
357 
358 		printf("natsemi: EEPROM contents:\n");
359 		for (i = 0; i <= EEPROM_SIZE; i++) {
360 			short eedata = read_eeprom(dev, EECtrl, i);
361 			printf(" %04hx", eedata);
362 		}
363 		printf("\n");
364 
365 		/* get MAC address */
366 		prev_eedata = read_eeprom(dev, EECtrl, 6);
367 		for (i = 0; i < 3; i++) {
368 			int eedata = read_eeprom(dev, EECtrl, i + 7);
369 			dev->enetaddr[i*2] = (eedata << 1) + (prev_eedata >> 15);
370 			dev->enetaddr[i*2+1] = eedata >> 7;
371 			prev_eedata = eedata;
372 		}
373 
374 		/* Reset the chip to erase any previous misconfiguration. */
375 		OUTL(dev, ChipReset, ChipCmd);
376 
377 		advertising = mdio_read(dev, 1, 4);
378 		chip_config = INL(dev, ChipConfig);
379 #ifdef NATSEMI_DEBUG
380 		printf("%s: Transceiver status %#08X advertising %#08X\n",
381 			dev->name, (int) INL(dev, BasicStatus), advertising);
382 		printf("%s: Transceiver default autoneg. %s 10%s %s duplex.\n",
383 			dev->name, chip_config & AnegMask ? "enabled, advertise" :
384 			"disabled, force", chip_config & SpeedMask ? "0" : "",
385 			chip_config & DuplexMask ? "full" : "half");
386 #endif
387 		chip_config |= AnegEnBothBoth;
388 #ifdef NATSEMI_DEBUG
389 		printf("%s: changed to autoneg. %s 10%s %s duplex.\n",
390 			dev->name, chip_config & AnegMask ? "enabled, advertise" :
391 			"disabled, force", chip_config & SpeedMask ? "0" : "",
392 			chip_config & DuplexMask ? "full" : "half");
393 #endif
394 		/*write new autoneg bits, reset phy*/
395 		OUTL(dev, (chip_config | PhyRst), ChipConfig);
396 		/*un-reset phy*/
397 		OUTL(dev, chip_config, ChipConfig);
398 
399 		/* Disable PME:
400 		 * The PME bit is initialized from the EEPROM contents.
401 		 * PCI cards probably have PME disabled, but motherboard
402 		 * implementations may have PME set to enable WakeOnLan.
403 		 * With PME set the chip will scan incoming packets but
404 		 * nothing will be written to memory. */
405 		SavedClkRun = INL(dev, ClkRun);
406 		OUTL(dev, SavedClkRun & ~0x100, ClkRun);
407 	}
408 	return card_number;
409 }
410 
411 /* Read the EEPROM and MII Management Data I/O (MDIO) interfaces.
412    The EEPROM code is for common 93c06/46 EEPROMs w/ 6bit addresses.  */
413 
414 /* Delay between EEPROM clock transitions.
415    No extra delay is needed with 33MHz PCI, but future 66MHz
416    access may need a delay. */
417 #define eeprom_delay(ee_addr)	INL(dev, ee_addr)
418 
419 enum EEPROM_Ctrl_Bits {
420 	EE_ShiftClk = 0x04,
421 	EE_DataIn = 0x01,
422 	EE_ChipSelect = 0x08,
423 	EE_DataOut = 0x02
424 };
425 
426 #define EE_Write0 (EE_ChipSelect)
427 #define EE_Write1 (EE_ChipSelect | EE_DataIn)
428 /* The EEPROM commands include the alway-set leading bit. */
429 enum EEPROM_Cmds {
430 	EE_WrEnCmd = (4 << 6), EE_WriteCmd = (5 << 6),
431 	EE_ReadCmd = (6 << 6), EE_EraseCmd = (7 << 6),
432 };
433 
434 #if 0
435 static void
436 write_eeprom(struct eth_device *dev, long addr, int location, short value)
437 {
438 	int i;
439 	int ee_addr = (typeof(ee_addr))addr;
440 	short wren_cmd = EE_WrEnCmd | 0x30; /*wren is 100 + 11XXXX*/
441 	short write_cmd = location | EE_WriteCmd;
442 
443 #ifdef NATSEMI_DEBUG
444 	printf("write_eeprom: %08x, %04hx, %04hx\n",
445 		dev->iobase + ee_addr, write_cmd, value);
446 #endif
447 	/* Shift the write enable command bits out. */
448 	for (i = 9; i >= 0; i--) {
449 		short cmdval = (wren_cmd & (1 << i)) ? EE_Write1 : EE_Write0;
450 		OUTL(dev, cmdval, ee_addr);
451 		eeprom_delay(ee_addr);
452 		OUTL(dev, cmdval | EE_ShiftClk, ee_addr);
453 		eeprom_delay(ee_addr);
454 	}
455 
456 	OUTL(dev, 0, ee_addr); /*bring chip select low*/
457 	OUTL(dev, EE_ShiftClk, ee_addr);
458 	eeprom_delay(ee_addr);
459 
460 	/* Shift the write command bits out. */
461 	for (i = 9; i >= 0; i--) {
462 		short cmdval = (write_cmd & (1 << i)) ? EE_Write1 : EE_Write0;
463 		OUTL(dev, cmdval, ee_addr);
464 		eeprom_delay(ee_addr);
465 		OUTL(dev, cmdval | EE_ShiftClk, ee_addr);
466 		eeprom_delay(ee_addr);
467 	}
468 
469 	for (i = 0; i < 16; i++) {
470 		short cmdval = (value & (1 << i)) ? EE_Write1 : EE_Write0;
471 		OUTL(dev, cmdval, ee_addr);
472 		eeprom_delay(ee_addr);
473 		OUTL(dev, cmdval | EE_ShiftClk, ee_addr);
474 		eeprom_delay(ee_addr);
475 	}
476 
477 	OUTL(dev, 0, ee_addr); /*bring chip select low*/
478 	OUTL(dev, EE_ShiftClk, ee_addr);
479 	for (i = 0; i < 200000; i++) {
480 		OUTL(dev, EE_Write0, ee_addr); /*poll for done*/
481 		if (INL(dev, ee_addr) & EE_DataOut) {
482 		    break; /*finished*/
483 		}
484 	}
485 	eeprom_delay(ee_addr);
486 
487 	/* Terminate the EEPROM access. */
488 	OUTL(dev, EE_Write0, ee_addr);
489 	OUTL(dev, 0, ee_addr);
490 	return;
491 }
492 #endif
493 
494 static int
495 read_eeprom(struct eth_device *dev, long addr, int location)
496 {
497 	int i;
498 	int retval = 0;
499 	int ee_addr = (typeof(ee_addr))addr;
500 	int read_cmd = location | EE_ReadCmd;
501 
502 	OUTL(dev, EE_Write0, ee_addr);
503 
504 	/* Shift the read command bits out. */
505 	for (i = 10; i >= 0; i--) {
506 		short dataval = (read_cmd & (1 << i)) ? EE_Write1 : EE_Write0;
507 		OUTL(dev, dataval, ee_addr);
508 		eeprom_delay(ee_addr);
509 		OUTL(dev, dataval | EE_ShiftClk, ee_addr);
510 		eeprom_delay(ee_addr);
511 	}
512 	OUTL(dev, EE_ChipSelect, ee_addr);
513 	eeprom_delay(ee_addr);
514 
515 	for (i = 0; i < 16; i++) {
516 		OUTL(dev, EE_ChipSelect | EE_ShiftClk, ee_addr);
517 		eeprom_delay(ee_addr);
518 		retval |= (INL(dev, ee_addr) & EE_DataOut) ? 1 << i : 0;
519 		OUTL(dev, EE_ChipSelect, ee_addr);
520 		eeprom_delay(ee_addr);
521 	}
522 
523 	/* Terminate the EEPROM access. */
524 	OUTL(dev, EE_Write0, ee_addr);
525 	OUTL(dev, 0, ee_addr);
526 #ifdef NATSEMI_DEBUG
527 	if (natsemi_debug)
528 		printf("read_eeprom: %08x, %08x, retval %08x\n",
529 			dev->iobase + ee_addr, read_cmd, retval);
530 #endif
531 	return retval;
532 }
533 
534 /*  MII transceiver control section.
535 	The 83815 series has an internal transceiver, and we present the
536 	management registers as if they were MII connected. */
537 
538 static int
539 mdio_read(struct eth_device *dev, int phy_id, int location)
540 {
541 	if (phy_id == 1 && location < 32)
542 		return INL(dev, BasicControl+(location<<2))&0xffff;
543 	else
544 		return 0xffff;
545 }
546 
547 /* Function: natsemi_init
548  *
549  * Description: resets the ethernet controller chip and configures
550  *    registers and data structures required for sending and receiving packets.
551  *
552  * Arguments: struct eth_device *dev:          NIC data structure
553  *
554  * returns:	int.
555  */
556 
557 static int
558 natsemi_init(struct eth_device *dev, bd_t * bis)
559 {
560 
561 	natsemi_reset(dev);
562 
563 	/* Disable PME:
564 	 * The PME bit is initialized from the EEPROM contents.
565 	 * PCI cards probably have PME disabled, but motherboard
566 	 * implementations may have PME set to enable WakeOnLan.
567 	 * With PME set the chip will scan incoming packets but
568 	 * nothing will be written to memory. */
569 	OUTL(dev, SavedClkRun & ~0x100, ClkRun);
570 
571 	natsemi_init_rxfilter(dev);
572 	natsemi_init_txd(dev);
573 	natsemi_init_rxd(dev);
574 
575 	/* Configure the PCI bus bursts and FIFO thresholds. */
576 	tx_config = TxAutoPad | TxCollRetry | TxMxdma_256 | (0x1002);
577 	rx_config = RxMxdma_256 | 0x20;
578 
579 #ifdef NATSEMI_DEBUG
580 	printf("%s: Setting TxConfig Register %#08X\n", dev->name, tx_config);
581 	printf("%s: Setting RxConfig Register %#08X\n", dev->name, rx_config);
582 #endif
583 	OUTL(dev, tx_config, TxConfig);
584 	OUTL(dev, rx_config, RxConfig);
585 
586 	natsemi_check_duplex(dev);
587 	natsemi_set_rx_mode(dev);
588 
589 	OUTL(dev, (RxOn | TxOn), ChipCmd);
590 	return 1;
591 }
592 
593 /*
594  * Function: natsemi_reset
595  *
596  * Description: soft resets the controller chip
597  *
598  * Arguments: struct eth_device *dev:          NIC data structure
599  *
600  * Returns:   void.
601  */
602 static void
603 natsemi_reset(struct eth_device *dev)
604 {
605 	OUTL(dev, ChipReset, ChipCmd);
606 
607 	/* On page 78 of the spec, they recommend some settings for "optimum
608 	   performance" to be done in sequence.  These settings optimize some
609 	   of the 100Mbit autodetection circuitry.  Also, we only want to do
610 	   this for rev C of the chip.  */
611 	if (INL(dev, SiliconRev) == 0x302) {
612 		OUTW(dev, 0x0001, PGSEL);
613 		OUTW(dev, 0x189C, PMDCSR);
614 		OUTW(dev, 0x0000, TSTDAT);
615 		OUTW(dev, 0x5040, DSPCFG);
616 		OUTW(dev, 0x008C, SDCFG);
617 	}
618 	/* Disable interrupts using the mask. */
619 	OUTL(dev, 0, IntrMask);
620 	OUTL(dev, 0, IntrEnable);
621 }
622 
623 /* Function: natsemi_init_rxfilter
624  *
625  * Description: sets receive filter address to our MAC address
626  *
627  * Arguments: struct eth_device *dev:          NIC data structure
628  *
629  * returns:   void.
630  */
631 
632 static void
633 natsemi_init_rxfilter(struct eth_device *dev)
634 {
635 	int i;
636 
637 	for (i = 0; i < ETH_ALEN; i += 2) {
638 		OUTL(dev, i, RxFilterAddr);
639 		OUTW(dev, dev->enetaddr[i] + (dev->enetaddr[i + 1] << 8),
640 		     RxFilterData);
641 	}
642 }
643 
644 /*
645  * Function: natsemi_init_txd
646  *
647  * Description: initializes the Tx descriptor
648  *
649  * Arguments: struct eth_device *dev:          NIC data structure
650  *
651  * returns:   void.
652  */
653 
654 static void
655 natsemi_init_txd(struct eth_device *dev)
656 {
657 	txd.link = (u32) 0;
658 	txd.cmdsts = (u32) 0;
659 	txd.bufptr = (u32) & txb[0];
660 
661 	/* load Transmit Descriptor Register */
662 	OUTL(dev, (u32) & txd, TxRingPtr);
663 #ifdef NATSEMI_DEBUG
664 	printf("natsemi_init_txd: TX descriptor reg loaded with: %#08X\n",
665 	       INL(dev, TxRingPtr));
666 #endif
667 }
668 
669 /* Function: natsemi_init_rxd
670  *
671  * Description: initializes the Rx descriptor ring
672  *
673  * Arguments: struct eth_device *dev:          NIC data structure
674  *
675  * Returns:   void.
676  */
677 
678 static void
679 natsemi_init_rxd(struct eth_device *dev)
680 {
681 	int i;
682 
683 	cur_rx = 0;
684 
685 	/* init RX descriptor */
686 	for (i = 0; i < NUM_RX_DESC; i++) {
687 		rxd[i].link =
688 		    cpu_to_le32((i + 1 <
689 				 NUM_RX_DESC) ? (u32) & rxd[i +
690 							    1] : (u32) &
691 				rxd[0]);
692 		rxd[i].cmdsts = cpu_to_le32((u32) RX_BUF_SIZE);
693 		rxd[i].bufptr = cpu_to_le32((u32) & rxb[i * RX_BUF_SIZE]);
694 #ifdef NATSEMI_DEBUG
695 		printf
696 		    ("natsemi_init_rxd: rxd[%d]=%p link=%X cmdsts=%lX bufptr=%X\n",
697 			i, &rxd[i], le32_to_cpu(rxd[i].link),
698 				rxd[i].cmdsts, rxd[i].bufptr);
699 #endif
700 	}
701 
702 	/* load Receive Descriptor Register */
703 	OUTL(dev, (u32) & rxd[0], RxRingPtr);
704 
705 #ifdef NATSEMI_DEBUG
706 	printf("natsemi_init_rxd: RX descriptor register loaded with: %X\n",
707 	       INL(dev, RxRingPtr));
708 #endif
709 }
710 
711 /* Function: natsemi_set_rx_mode
712  *
713  * Description:
714  *    sets the receive mode to accept all broadcast packets and packets
715  *    with our MAC address, and reject all multicast packets.
716  *
717  * Arguments: struct eth_device *dev:          NIC data structure
718  *
719  * Returns:   void.
720  */
721 
722 static void
723 natsemi_set_rx_mode(struct eth_device *dev)
724 {
725 	u32 rx_mode = AcceptBroadcast | AcceptMyPhys;
726 
727 	OUTL(dev, rx_mode, RxFilterAddr);
728 }
729 
730 static void
731 natsemi_check_duplex(struct eth_device *dev)
732 {
733 	int duplex = INL(dev, ChipConfig) & FullDuplex ? 1 : 0;
734 
735 #ifdef NATSEMI_DEBUG
736 	printf("%s: Setting %s-duplex based on negotiated link"
737 	       " capability.\n", dev->name, duplex ? "full" : "half");
738 #endif
739 	if (duplex) {
740 		rx_config |= RxAcceptTx;
741 		tx_config |= (TxCarrierIgn | TxHeartIgn);
742 	} else {
743 		rx_config &= ~RxAcceptTx;
744 		tx_config &= ~(TxCarrierIgn | TxHeartIgn);
745 	}
746 	OUTL(dev, tx_config, TxConfig);
747 	OUTL(dev, rx_config, RxConfig);
748 }
749 
750 /* Function: natsemi_send
751  *
752  * Description: transmits a packet and waits for completion or timeout.
753  *
754  * Returns:   void.  */
755 static int natsemi_send(struct eth_device *dev, void *packet, int length)
756 {
757 	u32 i, status = 0;
758 	u32 tx_status = 0;
759 	u32 *tx_ptr = &tx_status;
760 	vu_long *res = (vu_long *)tx_ptr;
761 
762 	/* Stop the transmitter */
763 	OUTL(dev, TxOff, ChipCmd);
764 
765 #ifdef NATSEMI_DEBUG
766 	if (natsemi_debug)
767 		printf("natsemi_send: sending %d bytes\n", (int) length);
768 #endif
769 
770 	/* set the transmit buffer descriptor and enable Transmit State Machine */
771 	txd.link = cpu_to_le32(0);
772 	txd.bufptr = cpu_to_le32(phys_to_bus((u32) packet));
773 	txd.cmdsts = cpu_to_le32(DescOwn | length);
774 
775 	/* load Transmit Descriptor Register */
776 	OUTL(dev, phys_to_bus((u32) & txd), TxRingPtr);
777 #ifdef NATSEMI_DEBUG
778 	if (natsemi_debug)
779 	    printf("natsemi_send: TX descriptor register loaded with: %#08X\n",
780 	     INL(dev, TxRingPtr));
781 #endif
782 	/* restart the transmitter */
783 	OUTL(dev, TxOn, ChipCmd);
784 
785 	for (i = 0;
786 	     (*res = le32_to_cpu(txd.cmdsts)) & DescOwn;
787 	     i++) {
788 		if (i >= TOUT_LOOP) {
789 			printf
790 			    ("%s: tx error buffer not ready: txd.cmdsts == %#X\n",
791 			     dev->name, tx_status);
792 			goto Done;
793 		}
794 	}
795 
796 	if (!(tx_status & DescPktOK)) {
797 		printf("natsemi_send: Transmit error, Tx status %X.\n",
798 		       tx_status);
799 		goto Done;
800 	}
801 
802 	status = 1;
803       Done:
804 	return status;
805 }
806 
807 /* Function: natsemi_poll
808  *
809  * Description: checks for a received packet and returns it if found.
810  *
811  * Arguments: struct eth_device *dev:          NIC data structure
812  *
813  * Returns:   1 if    packet was received.
814  *            0 if no packet was received.
815  *
816  * Side effects:
817  *            Returns (copies) the packet to the array dev->packet.
818  *            Returns the length of the packet.
819  */
820 
821 static int
822 natsemi_poll(struct eth_device *dev)
823 {
824 	int retstat = 0;
825 	int length = 0;
826 	u32 rx_status = le32_to_cpu(rxd[cur_rx].cmdsts);
827 
828 	if (!(rx_status & (u32) DescOwn))
829 		return retstat;
830 #ifdef NATSEMI_DEBUG
831 	if (natsemi_debug)
832 		printf("natsemi_poll: got a packet: cur_rx:%d, status:%X\n",
833 		       cur_rx, rx_status);
834 #endif
835 	length = (rx_status & DSIZE) - CRC_SIZE;
836 
837 	if ((rx_status & (DescMore | DescPktOK | DescRxLong)) != DescPktOK) {
838 		printf
839 		    ("natsemi_poll: Corrupted packet received, buffer status = %X\n",
840 		     rx_status);
841 		retstat = 0;
842 	} else {		/* give packet to higher level routine */
843 		net_process_received_packet((rxb + cur_rx * RX_BUF_SIZE),
844 					    length);
845 		retstat = 1;
846 	}
847 
848 	/* return the descriptor and buffer to receive ring */
849 	rxd[cur_rx].cmdsts = cpu_to_le32(RX_BUF_SIZE);
850 	rxd[cur_rx].bufptr = cpu_to_le32((u32) & rxb[cur_rx * RX_BUF_SIZE]);
851 
852 	if (++cur_rx == NUM_RX_DESC)
853 		cur_rx = 0;
854 
855 	/* re-enable the potentially idle receive state machine */
856 	OUTL(dev, RxOn, ChipCmd);
857 
858 	return retstat;
859 }
860 
861 /* Function: natsemi_disable
862  *
863  * Description: Turns off interrupts and stops Tx and Rx engines
864  *
865  * Arguments: struct eth_device *dev:          NIC data structure
866  *
867  * Returns:   void.
868  */
869 
870 static void
871 natsemi_disable(struct eth_device *dev)
872 {
873 	/* Disable interrupts using the mask. */
874 	OUTL(dev, 0, IntrMask);
875 	OUTL(dev, 0, IntrEnable);
876 
877 	/* Stop the chip's Tx and Rx processes. */
878 	OUTL(dev, RxOff | TxOff, ChipCmd);
879 
880 	/* Restore PME enable bit */
881 	OUTL(dev, SavedClkRun, ClkRun);
882 }
883