xref: /openbmc/u-boot/drivers/net/lan91c96.c (revision cf0bcd7d)
1 /*------------------------------------------------------------------------
2  * lan91c96.c
3  * This is a driver for SMSC's LAN91C96 single-chip Ethernet device, based
4  * on the SMC91111 driver from U-Boot.
5  *
6  * (C) Copyright 2002
7  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
8  * Rolf Offermanns <rof@sysgo.de>
9  *
10  * Copyright (C) 2001 Standard Microsystems Corporation (SMSC)
11  *       Developed by Simple Network Magic Corporation (SNMC)
12  * Copyright (C) 1996 by Erik Stahlman (ES)
13  *
14  * SPDX-License-Identifier:	GPL-2.0+
15  *
16  * Information contained in this file was obtained from the LAN91C96
17  * manual from SMC.  To get a copy, if you really want one, you can find
18  * information under www.smsc.com.
19  *
20  * "Features" of the SMC chip:
21  *   6144 byte packet memory. ( for the 91C96 )
22  *   EEPROM for configuration
23  *   AUI/TP selection  ( mine has 10Base2/10BaseT select )
24  *
25  * Arguments:
26  *	io	= for the base address
27  *	irq	= for the IRQ
28  *
29  * author:
30  *	Erik Stahlman				( erik@vt.edu )
31  *	Daris A Nevil				( dnevil@snmc.com )
32  *
33  *
34  * Hardware multicast code from Peter Cammaert ( pc@denkart.be )
35  *
36  * Sources:
37  *    o   SMSC LAN91C96 databook (www.smsc.com)
38  *    o   smc91111.c (u-boot driver)
39  *    o   smc9194.c (linux kernel driver)
40  *    o   lan91c96.c (Intel Diagnostic Manager driver)
41  *
42  * History:
43  *	04/30/03  Mathijs Haarman	Modified smc91111.c (u-boot version)
44  *					for lan91c96
45  *---------------------------------------------------------------------------
46  */
47 
48 #include <common.h>
49 #include <command.h>
50 #include <malloc.h>
51 #include "lan91c96.h"
52 #include <net.h>
53 #include <linux/compiler.h>
54 
55 /*------------------------------------------------------------------------
56  *
57  * Configuration options, for the experienced user to change.
58  *
59  -------------------------------------------------------------------------*/
60 
61 /* Use power-down feature of the chip */
62 #define POWER_DOWN	0
63 
64 /*
65  * Wait time for memory to be free.  This probably shouldn't be
66  * tuned that much, as waiting for this means nothing else happens
67  * in the system
68 */
69 #define MEMORY_WAIT_TIME 16
70 
71 #define SMC_DEBUG 0
72 
73 #if (SMC_DEBUG > 2 )
74 #define PRINTK3(args...) printf(args)
75 #else
76 #define PRINTK3(args...)
77 #endif
78 
79 #if SMC_DEBUG > 1
80 #define PRINTK2(args...) printf(args)
81 #else
82 #define PRINTK2(args...)
83 #endif
84 
85 #ifdef SMC_DEBUG
86 #define PRINTK(args...) printf(args)
87 #else
88 #define PRINTK(args...)
89 #endif
90 
91 
92 /*------------------------------------------------------------------------
93  *
94  * The internal workings of the driver.  If you are changing anything
95  * here with the SMC stuff, you should have the datasheet and know
96  * what you are doing.
97  *
98  *------------------------------------------------------------------------
99  */
100 #define DRIVER_NAME "LAN91C96"
101 #define SMC_ALLOC_MAX_TRY 5
102 #define SMC_TX_TIMEOUT 30
103 
104 #define ETH_ZLEN 60
105 
106 #ifdef  CONFIG_LAN91C96_USE_32_BIT
107 #define USE_32_BIT  1
108 #else
109 #undef USE_32_BIT
110 #endif
111 
112 /* See if a MAC address is defined in the current environment. If so use it. If not
113  . print a warning and set the environment and other globals with the default.
114  . If an EEPROM is present it really should be consulted.
115 */
116 static int smc_get_ethaddr(bd_t *bd, struct eth_device *dev);
117 static int get_rom_mac(struct eth_device *dev, unsigned char *v_rom_mac);
118 
119 /* ------------------------------------------------------------
120  * Internal routines
121  * ------------------------------------------------------------
122  */
123 
124 static unsigned char smc_mac_addr[] = { 0xc0, 0x00, 0x00, 0x1b, 0x62, 0x9c };
125 
126 /*
127  * This function must be called before smc_open() if you want to override
128  * the default mac address.
129  */
130 
131 static void smc_set_mac_addr(const unsigned char *addr)
132 {
133 	int i;
134 
135 	for (i = 0; i < sizeof (smc_mac_addr); i++) {
136 		smc_mac_addr[i] = addr[i];
137 	}
138 }
139 
140 /***********************************************
141  * Show available memory                       *
142  ***********************************************/
143 void dump_memory_info(struct eth_device *dev)
144 {
145 	__maybe_unused word mem_info;
146 	word old_bank;
147 
148 	old_bank = SMC_inw(dev, LAN91C96_BANK_SELECT) & 0xF;
149 
150 	SMC_SELECT_BANK(dev, 0);
151 	mem_info = SMC_inw(dev, LAN91C96_MIR);
152 	PRINTK2 ("Memory: %4d available\n", (mem_info >> 8) * 2048);
153 
154 	SMC_SELECT_BANK(dev, old_bank);
155 }
156 
157 /*
158  * A rather simple routine to print out a packet for debugging purposes.
159  */
160 #if SMC_DEBUG > 2
161 static void print_packet (byte *, int);
162 #endif
163 
164 static int poll4int (struct eth_device *dev, byte mask, int timeout)
165 {
166 	int tmo = get_timer (0) + timeout * CONFIG_SYS_HZ;
167 	int is_timeout = 0;
168 	word old_bank = SMC_inw(dev, LAN91C96_BANK_SELECT);
169 
170 	PRINTK2 ("Polling...\n");
171 	SMC_SELECT_BANK(dev, 2);
172 	while ((SMC_inw(dev, LAN91C96_INT_STATS) & mask) == 0) {
173 		if (get_timer (0) >= tmo) {
174 			is_timeout = 1;
175 			break;
176 		}
177 	}
178 
179 	/* restore old bank selection */
180 	SMC_SELECT_BANK(dev, old_bank);
181 
182 	if (is_timeout)
183 		return 1;
184 	else
185 		return 0;
186 }
187 
188 /*
189  * Function: smc_reset
190  * Purpose:
191  *	This sets the SMC91111 chip to its normal state, hopefully from whatever
192  *	mess that any other DOS driver has put it in.
193  *
194  * Maybe I should reset more registers to defaults in here?  SOFTRST  should
195  * do that for me.
196  *
197  * Method:
198  *	1.  send a SOFT RESET
199  *	2.  wait for it to finish
200  *	3.  enable autorelease mode
201  *	4.  reset the memory management unit
202  *	5.  clear all interrupts
203  *
204 */
205 static void smc_reset(struct eth_device *dev)
206 {
207 	PRINTK2("%s:smc_reset\n", dev->name);
208 
209 	/* This resets the registers mostly to defaults, but doesn't
210 	   affect EEPROM.  That seems unnecessary */
211 	SMC_SELECT_BANK(dev, 0);
212 	SMC_outw(dev, LAN91C96_RCR_SOFT_RST, LAN91C96_RCR);
213 
214 	udelay (10);
215 
216 	/* Disable transmit and receive functionality */
217 	SMC_outw(dev, 0, LAN91C96_RCR);
218 	SMC_outw(dev, 0, LAN91C96_TCR);
219 
220 	/* set the control register */
221 	SMC_SELECT_BANK(dev, 1);
222 	SMC_outw(dev, SMC_inw(dev, LAN91C96_CONTROL) | LAN91C96_CTR_BIT_8,
223 			  LAN91C96_CONTROL);
224 
225 	/* Disable all interrupts */
226 	SMC_outb(dev, 0, LAN91C96_INT_MASK);
227 }
228 
229 /*
230  * Function: smc_enable
231  * Purpose: let the chip talk to the outside work
232  * Method:
233  *	1.  Initialize the Memory Configuration Register
234  *	2.  Enable the transmitter
235  *	3.  Enable the receiver
236 */
237 static void smc_enable(struct eth_device *dev)
238 {
239 	PRINTK2("%s:smc_enable\n", dev->name);
240 	SMC_SELECT_BANK(dev, 0);
241 
242 	/* Initialize the Memory Configuration Register. See page
243 	   49 of the LAN91C96 data sheet for details. */
244 	SMC_outw(dev, LAN91C96_MCR_TRANSMIT_PAGES, LAN91C96_MCR);
245 
246 	/* Initialize the Transmit Control Register */
247 	SMC_outw(dev, LAN91C96_TCR_TXENA, LAN91C96_TCR);
248 	/* Initialize the Receive Control Register
249 	 * FIXME:
250 	 * The promiscuous bit set because I could not receive ARP reply
251 	 * packets from the server when I send a ARP request. It only works
252 	 * when I set the promiscuous bit
253 	 */
254 	SMC_outw(dev, LAN91C96_RCR_RXEN | LAN91C96_RCR_PRMS, LAN91C96_RCR);
255 }
256 
257 /*
258  * Function: smc_shutdown
259  * Purpose:  closes down the SMC91xxx chip.
260  * Method:
261  *	1. zero the interrupt mask
262  *	2. clear the enable receive flag
263  *	3. clear the enable xmit flags
264  *
265  * TODO:
266  *   (1) maybe utilize power down mode.
267  *	Why not yet?  Because while the chip will go into power down mode,
268  *	the manual says that it will wake up in response to any I/O requests
269  *	in the register space.   Empirical results do not show this working.
270  */
271 static void smc_shutdown(struct eth_device *dev)
272 {
273 	PRINTK2("%s:smc_shutdown\n", dev->name);
274 
275 	/* no more interrupts for me */
276 	SMC_SELECT_BANK(dev, 2);
277 	SMC_outb(dev, 0, LAN91C96_INT_MASK);
278 
279 	/* and tell the card to stay away from that nasty outside world */
280 	SMC_SELECT_BANK(dev, 0);
281 	SMC_outb(dev, 0, LAN91C96_RCR);
282 	SMC_outb(dev, 0, LAN91C96_TCR);
283 }
284 
285 
286 /*
287  * Function:  smc_hardware_send_packet(struct net_device * )
288  * Purpose:
289  *	This sends the actual packet to the SMC9xxx chip.
290  *
291  * Algorithm:
292  *	First, see if a saved_skb is available.
293  *		( this should NOT be called if there is no 'saved_skb'
294  *	Now, find the packet number that the chip allocated
295  *	Point the data pointers at it in memory
296  *	Set the length word in the chip's memory
297  *	Dump the packet to chip memory
298  *	Check if a last byte is needed ( odd length packet )
299  *		if so, set the control flag right
300  *	Tell the card to send it
301  *	Enable the transmit interrupt, so I know if it failed
302  *	Free the kernel data if I actually sent it.
303  */
304 static int smc_send_packet(struct eth_device *dev, void *packet,
305 		int packet_length)
306 {
307 	byte packet_no;
308 	byte *buf;
309 	int length;
310 	int numPages;
311 	int try = 0;
312 	int time_out;
313 	byte status;
314 
315 
316 	PRINTK3("%s:smc_hardware_send_packet\n", dev->name);
317 
318 	length = ETH_ZLEN < packet_length ? packet_length : ETH_ZLEN;
319 
320 	/* allocate memory
321 	 ** The MMU wants the number of pages to be the number of 256 bytes
322 	 ** 'pages', minus 1 ( since a packet can't ever have 0 pages :) )
323 	 **
324 	 ** The 91C111 ignores the size bits, but the code is left intact
325 	 ** for backwards and future compatibility.
326 	 **
327 	 ** Pkt size for allocating is data length +6 (for additional status
328 	 ** words, length and ctl!)
329 	 **
330 	 ** If odd size then last byte is included in this header.
331 	 */
332 	numPages = ((length & 0xfffe) + 6);
333 	numPages >>= 8;				/* Divide by 256 */
334 
335 	if (numPages > 7) {
336 		printf("%s: Far too big packet error. \n", dev->name);
337 		return 0;
338 	}
339 
340 	/* now, try to allocate the memory */
341 
342 	SMC_SELECT_BANK(dev, 2);
343 	SMC_outw(dev, LAN91C96_MMUCR_ALLOC_TX | numPages, LAN91C96_MMU);
344 
345   again:
346 	try++;
347 	time_out = MEMORY_WAIT_TIME;
348 	do {
349 		status = SMC_inb(dev, LAN91C96_INT_STATS);
350 		if (status & LAN91C96_IST_ALLOC_INT) {
351 
352 			SMC_outb(dev, LAN91C96_IST_ALLOC_INT,
353 					LAN91C96_INT_STATS);
354 			break;
355 		}
356 	} while (--time_out);
357 
358 	if (!time_out) {
359 		PRINTK2 ("%s: memory allocation, try %d failed ...\n",
360 				 dev->name, try);
361 		if (try < SMC_ALLOC_MAX_TRY)
362 			goto again;
363 		else
364 			return 0;
365 	}
366 
367 	PRINTK2 ("%s: memory allocation, try %d succeeded ...\n",
368 			 dev->name, try);
369 
370 	/* I can send the packet now.. */
371 	buf = (byte *) packet;
372 
373 	/* If I get here, I _know_ there is a packet slot waiting for me */
374 	packet_no = SMC_inb(dev, LAN91C96_ARR);
375 	if (packet_no & LAN91C96_ARR_FAILED) {
376 		/* or isn't there?  BAD CHIP! */
377 		printf("%s: Memory allocation failed. \n", dev->name);
378 		return 0;
379 	}
380 
381 	/* we have a packet address, so tell the card to use it */
382 	SMC_outb(dev, packet_no, LAN91C96_PNR);
383 
384 	/* point to the beginning of the packet */
385 	SMC_outw(dev, LAN91C96_PTR_AUTO_INCR, LAN91C96_POINTER);
386 
387 	PRINTK3("%s: Trying to xmit packet of length %x\n",
388 			 dev->name, length);
389 
390 #if SMC_DEBUG > 2
391 	printf ("Transmitting Packet\n");
392 	print_packet (buf, length);
393 #endif
394 
395 	/* send the packet length ( +6 for status, length and ctl byte )
396 	   and the status word ( set to zeros ) */
397 #ifdef USE_32_BIT
398 	SMC_outl(dev, (length + 6) << 16, LAN91C96_DATA_HIGH);
399 #else
400 	SMC_outw(dev, 0, LAN91C96_DATA_HIGH);
401 	/* send the packet length ( +6 for status words, length, and ctl */
402 	SMC_outw(dev, (length + 6), LAN91C96_DATA_HIGH);
403 #endif /* USE_32_BIT */
404 
405 	/* send the actual data
406 	 * I _think_ it's faster to send the longs first, and then
407 	 * mop up by sending the last word.  It depends heavily
408 	 * on alignment, at least on the 486.  Maybe it would be
409 	 * a good idea to check which is optimal?  But that could take
410 	 * almost as much time as is saved?
411 	 */
412 #ifdef USE_32_BIT
413 	SMC_outsl(dev, LAN91C96_DATA_HIGH, buf, length >> 2);
414 	if (length & 0x2)
415 		SMC_outw(dev, *((word *) (buf + (length & 0xFFFFFFFC))),
416 				  LAN91C96_DATA_HIGH);
417 #else
418 	SMC_outsw(dev, LAN91C96_DATA_HIGH, buf, (length) >> 1);
419 #endif /* USE_32_BIT */
420 
421 	/* Send the last byte, if there is one.   */
422 	if ((length & 1) == 0) {
423 		SMC_outw(dev, 0, LAN91C96_DATA_HIGH);
424 	} else {
425 		SMC_outw(dev, buf[length - 1] | 0x2000, LAN91C96_DATA_HIGH);
426 	}
427 
428 	/* and let the chipset deal with it */
429 	SMC_outw(dev, LAN91C96_MMUCR_ENQUEUE, LAN91C96_MMU);
430 
431 	/* poll for TX INT */
432 	if (poll4int (dev, LAN91C96_MSK_TX_INT, SMC_TX_TIMEOUT)) {
433 		/* sending failed */
434 		PRINTK2("%s: TX timeout, sending failed...\n", dev->name);
435 
436 		/* release packet */
437 		SMC_outw(dev, LAN91C96_MMUCR_RELEASE_TX, LAN91C96_MMU);
438 
439 		/* wait for MMU getting ready (low) */
440 		while (SMC_inw(dev, LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY)
441 			udelay (10);
442 
443 		PRINTK2("MMU ready\n");
444 
445 
446 		return 0;
447 	} else {
448 		/* ack. int */
449 		SMC_outw(dev, LAN91C96_IST_TX_INT, LAN91C96_INT_STATS);
450 
451 		PRINTK2("%s: Sent packet of length %d \n", dev->name, length);
452 
453 		/* release packet */
454 		SMC_outw(dev, LAN91C96_MMUCR_RELEASE_TX, LAN91C96_MMU);
455 
456 		/* wait for MMU getting ready (low) */
457 		while (SMC_inw(dev, LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY)
458 			udelay (10);
459 
460 		PRINTK2 ("MMU ready\n");
461 	}
462 
463 	return length;
464 }
465 
466 
467 /*
468  * Open and Initialize the board
469  *
470  * Set up everything, reset the card, etc ..
471  *
472  */
473 static int smc_open(bd_t *bd, struct eth_device *dev)
474 {
475 	int i, err;			/* used to set hw ethernet address */
476 
477 	PRINTK2("%s:smc_open\n", dev->name);
478 
479 	/* reset the hardware */
480 
481 	smc_reset(dev);
482 	smc_enable(dev);
483 
484 	SMC_SELECT_BANK(dev, 1);
485 	/* set smc_mac_addr, and sync it with u-boot globals */
486 	err = smc_get_ethaddr(bd, dev);
487 	if (err < 0)
488 		return -1;
489 #ifdef USE_32_BIT
490 	for (i = 0; i < 6; i += 2) {
491 		word address;
492 
493 		address = smc_mac_addr[i + 1] << 8;
494 		address |= smc_mac_addr[i];
495 		SMC_outw(dev, address, LAN91C96_IA0 + i);
496 	}
497 #else
498 	for (i = 0; i < 6; i++)
499 		SMC_outb(dev, smc_mac_addr[i], LAN91C96_IA0 + i);
500 #endif
501 	return 0;
502 }
503 
504 /*-------------------------------------------------------------
505  *
506  * smc_rcv -  receive a packet from the card
507  *
508  * There is ( at least ) a packet waiting to be read from
509  * chip-memory.
510  *
511  * o Read the status
512  * o If an error, record it
513  * o otherwise, read in the packet
514  *-------------------------------------------------------------
515  */
516 static int smc_rcv(struct eth_device *dev)
517 {
518 	int packet_number;
519 	word status;
520 	word packet_length;
521 	int is_error = 0;
522 
523 #ifdef USE_32_BIT
524 	dword stat_len;
525 #endif
526 
527 
528 	SMC_SELECT_BANK(dev, 2);
529 	packet_number = SMC_inw(dev, LAN91C96_FIFO);
530 
531 	if (packet_number & LAN91C96_FIFO_RXEMPTY) {
532 		return 0;
533 	}
534 
535 	PRINTK3("%s:smc_rcv\n", dev->name);
536 	/*  start reading from the start of the packet */
537 	SMC_outw(dev, LAN91C96_PTR_READ | LAN91C96_PTR_RCV |
538 			  LAN91C96_PTR_AUTO_INCR, LAN91C96_POINTER);
539 
540 	/* First two words are status and packet_length */
541 #ifdef USE_32_BIT
542 	stat_len = SMC_inl(dev, LAN91C96_DATA_HIGH);
543 	status = stat_len & 0xffff;
544 	packet_length = stat_len >> 16;
545 #else
546 	status = SMC_inw(dev, LAN91C96_DATA_HIGH);
547 	packet_length = SMC_inw(dev, LAN91C96_DATA_HIGH);
548 #endif
549 
550 	packet_length &= 0x07ff;	/* mask off top bits */
551 
552 	PRINTK2 ("RCV: STATUS %4x LENGTH %4x\n", status, packet_length);
553 
554 	if (!(status & FRAME_FILTER)) {
555 		/* Adjust for having already read the first two words */
556 		packet_length -= 4;		/*4; */
557 
558 
559 		/* set odd length for bug in LAN91C111, */
560 		/* which never sets RS_ODDFRAME */
561 		/* TODO ? */
562 
563 
564 #ifdef USE_32_BIT
565 		PRINTK3 (" Reading %d dwords (and %d bytes) \n",
566 			 packet_length >> 2, packet_length & 3);
567 		/* QUESTION:  Like in the TX routine, do I want
568 		   to send the DWORDs or the bytes first, or some
569 		   mixture.  A mixture might improve already slow PIO
570 		   performance  */
571 		SMC_insl(dev, LAN91C96_DATA_HIGH, net_rx_packets[0],
572 			 packet_length >> 2);
573 		/* read the left over bytes */
574 		if (packet_length & 3) {
575 			int i;
576 
577 			byte *tail = (byte *)(net_rx_packets[0] +
578 				(packet_length & ~3));
579 			dword leftover = SMC_inl(dev, LAN91C96_DATA_HIGH);
580 
581 			for (i = 0; i < (packet_length & 3); i++)
582 				*tail++ = (byte) (leftover >> (8 * i)) & 0xff;
583 		}
584 #else
585 		PRINTK3(" Reading %d words and %d byte(s)\n",
586 			(packet_length >> 1), packet_length & 1);
587 		SMC_insw(dev, LAN91C96_DATA_HIGH, net_rx_packets[0],
588 			 packet_length >> 1);
589 
590 #endif /* USE_32_BIT */
591 
592 #if	SMC_DEBUG > 2
593 		printf ("Receiving Packet\n");
594 		print_packet((byte *)net_rx_packets[0], packet_length);
595 #endif
596 	} else {
597 		/* error ... */
598 		/* TODO ? */
599 		is_error = 1;
600 	}
601 
602 	while (SMC_inw(dev, LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY)
603 		udelay (1);		/* Wait until not busy */
604 
605 	/*  error or good, tell the card to get rid of this packet */
606 	SMC_outw(dev, LAN91C96_MMUCR_RELEASE_RX, LAN91C96_MMU);
607 
608 	while (SMC_inw(dev, LAN91C96_MMU) & LAN91C96_MMUCR_NO_BUSY)
609 		udelay (1);		/* Wait until not busy */
610 
611 	if (!is_error) {
612 		/* Pass the packet up to the protocol layers. */
613 		net_process_received_packet(net_rx_packets[0], packet_length);
614 		return packet_length;
615 	} else {
616 		return 0;
617 	}
618 
619 }
620 
621 /*----------------------------------------------------
622  * smc_close
623  *
624  * this makes the board clean up everything that it can
625  * and not talk to the outside world.   Caused by
626  * an 'ifconfig ethX down'
627  *
628  -----------------------------------------------------*/
629 static int smc_close(struct eth_device *dev)
630 {
631 	PRINTK2("%s:smc_close\n", dev->name);
632 
633 	/* clear everything */
634 	smc_shutdown(dev);
635 
636 	return 0;
637 }
638 
639 #if SMC_DEBUG > 2
640 static void print_packet(byte *buf, int length)
641 {
642 #if 0
643 	int i;
644 	int remainder;
645 	int lines;
646 
647 	printf ("Packet of length %d \n", length);
648 
649 	lines = length / 16;
650 	remainder = length % 16;
651 
652 	for (i = 0; i < lines; i++) {
653 		int cur;
654 
655 		for (cur = 0; cur < 8; cur++) {
656 			byte a, b;
657 
658 			a = *(buf++);
659 			b = *(buf++);
660 			printf ("%02x%02x ", a, b);
661 		}
662 		printf ("\n");
663 	}
664 	for (i = 0; i < remainder / 2; i++) {
665 		byte a, b;
666 
667 		a = *(buf++);
668 		b = *(buf++);
669 		printf ("%02x%02x ", a, b);
670 	}
671 	printf ("\n");
672 #endif /* 0 */
673 }
674 #endif /* SMC_DEBUG > 2 */
675 
676 static int  lan91c96_init(struct eth_device *dev, bd_t *bd)
677 {
678 	return smc_open(bd, dev);
679 }
680 
681 static void lan91c96_halt(struct eth_device *dev)
682 {
683 	smc_close(dev);
684 }
685 
686 static int lan91c96_recv(struct eth_device *dev)
687 {
688 	return smc_rcv(dev);
689 }
690 
691 static int lan91c96_send(struct eth_device *dev, void *packet,
692 		int length)
693 {
694 	return smc_send_packet(dev, packet, length);
695 }
696 
697 /* smc_get_ethaddr
698  *
699  * This checks both the environment and the ROM for an ethernet address. If
700  * found, the environment takes precedence.
701  */
702 
703 static int smc_get_ethaddr(bd_t *bd, struct eth_device *dev)
704 {
705 	uchar v_mac[6];
706 
707 	if (!eth_env_get_enetaddr("ethaddr", v_mac)) {
708 		/* get ROM mac value if any */
709 		if (!get_rom_mac(dev, v_mac)) {
710 			printf("\n*** ERROR: ethaddr is NOT set !!\n");
711 			return -1;
712 		}
713 		eth_env_set_enetaddr("ethaddr", v_mac);
714 	}
715 
716 	smc_set_mac_addr(v_mac); /* use old function to update smc default */
717 	PRINTK("Using MAC Address %pM\n", v_mac);
718 	return 0;
719 }
720 
721 /*
722  * get_rom_mac()
723  * Note, this has omly been tested for the OMAP730 P2.
724  */
725 
726 static int get_rom_mac(struct eth_device *dev, unsigned char *v_rom_mac)
727 {
728 	int i;
729 	SMC_SELECT_BANK(dev, 1);
730 	for (i=0; i<6; i++)
731 	{
732 		v_rom_mac[i] = SMC_inb(dev, LAN91C96_IA0 + i);
733 	}
734 	return (1);
735 }
736 
737 /* Structure to detect the device IDs */
738 struct id_type {
739 	u8 id;
740 	char *name;
741 };
742 static struct id_type supported_chips[] = {
743 	{0, ""}, /* Dummy entry to prevent id check failure */
744 	{9, "LAN91C110"},
745 	{8, "LAN91C100FD"},
746 	{7, "LAN91C100"},
747 	{5, "LAN91C95"},
748 	{4, "LAN91C94/96"},
749 	{3, "LAN91C90/92"},
750 };
751 /* lan91c96_detect_chip
752  * See:
753  * http://www.embeddedsys.com/subpages/resources/images/documents/LAN91C96_datasheet.pdf
754  * page 71 - that is the closest we get to detect this device
755  */
756 static int lan91c96_detect_chip(struct eth_device *dev)
757 {
758 	u8 chip_id;
759 	int r;
760 	SMC_SELECT_BANK(dev, 3);
761 	chip_id = (SMC_inw(dev, 0xA) & LAN91C96_REV_CHIPID) >> 4;
762 	SMC_SELECT_BANK(dev, 0);
763 	for (r = 0; r < ARRAY_SIZE(supported_chips); r++)
764 		if (chip_id == supported_chips[r].id)
765 			return r;
766 	return 0;
767 }
768 
769 int lan91c96_initialize(u8 dev_num, int base_addr)
770 {
771 	struct eth_device *dev;
772 	int r = 0;
773 
774 	dev = malloc(sizeof(*dev));
775 	if (!dev) {
776 		return 0;
777 	}
778 	memset(dev, 0, sizeof(*dev));
779 
780 	dev->iobase = base_addr;
781 
782 	/* Try to detect chip. Will fail if not present. */
783 	r = lan91c96_detect_chip(dev);
784 	if (!r) {
785 		free(dev);
786 		return 0;
787 	}
788 	get_rom_mac(dev, dev->enetaddr);
789 
790 	dev->init = lan91c96_init;
791 	dev->halt = lan91c96_halt;
792 	dev->send = lan91c96_send;
793 	dev->recv = lan91c96_recv;
794 	sprintf(dev->name, "%s-%hu", supported_chips[r].name, dev_num);
795 
796 	eth_register(dev);
797 	return 0;
798 }
799