xref: /openbmc/u-boot/drivers/net/ne2000_base.c (revision d66ff4ba)
1 /*
2 Ported to U-Boot by Christian Pellegrin <chri@ascensit.com>
3 
4 Based on sources from the Linux kernel (pcnet_cs.c, 8390.h) and
5 eCOS(if_dp83902a.c, if_dp83902a.h). Both of these 2 wonderful world
6 are GPL, so this is, of course, GPL.
7 
8 ==========================================================================
9 
10 dev/if_dp83902a.c
11 
12 Ethernet device driver for NS DP83902a ethernet controller
13 
14 ==========================================================================
15 ####ECOSGPLCOPYRIGHTBEGIN####
16 -------------------------------------------
17 This file is part of eCos, the Embedded Configurable Operating System.
18 Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
19 
20 eCos is free software; you can redistribute it and/or modify it under
21 the terms of the GNU General Public License as published by the Free
22 Software Foundation; either version 2 or (at your option) any later version.
23 
24 eCos is distributed in the hope that it will be useful, but WITHOUT ANY
25 WARRANTY; without even the implied warranty of MERCHANTABILITY or
26 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
27 for more details.
28 
29 You should have received a copy of the GNU General Public License along
30 with eCos; if not, write to the Free Software Foundation, Inc.,
31 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
32 
33 As a special exception, if other files instantiate templates or use macros
34 or inline functions from this file, or you compile this file and link it
35 with other works to produce a work based on this file, this file does not
36 by itself cause the resulting work to be covered by the GNU General Public
37 License. However the source code for this file must still be made available
38 in accordance with section (3) of the GNU General Public License.
39 
40 This exception does not invalidate any other reasons why a work based on
41 this file might be covered by the GNU General Public License.
42 
43 Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
44 at http://sources.redhat.com/ecos/ecos-license/
45 -------------------------------------------
46 ####ECOSGPLCOPYRIGHTEND####
47 ####BSDCOPYRIGHTBEGIN####
48 
49 -------------------------------------------
50 
51 Portions of this software may have been derived from OpenBSD or other sources,
52 and are covered by the appropriate copyright disclaimers included herein.
53 
54 -------------------------------------------
55 
56 ####BSDCOPYRIGHTEND####
57 ==========================================================================
58 #####DESCRIPTIONBEGIN####
59 
60 Author(s):	gthomas
61 Contributors:	gthomas, jskov, rsandifo
62 Date:		2001-06-13
63 Purpose:
64 Description:
65 
66 FIXME:		Will fail if pinged with large packets (1520 bytes)
67 Add promisc config
68 Add SNMP
69 
70 ####DESCRIPTIONEND####
71 
72 ==========================================================================
73 */
74 
75 #include <common.h>
76 #include <command.h>
77 #include <environment.h>
78 #include <net.h>
79 #include <malloc.h>
80 #include <linux/compiler.h>
81 
82 /* forward definition of function used for the uboot interface */
83 void uboot_push_packet_len(int len);
84 void uboot_push_tx_done(int key, int val);
85 
86 /* NE2000 base header file */
87 #include "ne2000_base.h"
88 
89 #if defined(CONFIG_DRIVER_AX88796L)
90 /* AX88796L support */
91 #include "ax88796.h"
92 #else
93 /* Basic NE2000 chip support */
94 #include "ne2000.h"
95 #endif
96 
97 static dp83902a_priv_data_t nic; /* just one instance of the card supported */
98 
99 /**
100  * This function reads the MAC address from the serial EEPROM,
101  * used if PROM read fails. Does nothing for ax88796 chips (sh boards)
102  */
103 static bool
104 dp83902a_init(unsigned char *enetaddr)
105 {
106 	dp83902a_priv_data_t *dp = &nic;
107 	u8* base;
108 #if defined(NE2000_BASIC_INIT)
109 	int i;
110 #endif
111 
112 	DEBUG_FUNCTION();
113 
114 	base = dp->base;
115 	if (!base)
116 		return false;	/* No device found */
117 
118 	DEBUG_LINE();
119 
120 #if defined(NE2000_BASIC_INIT)
121 	/* AX88796L doesn't need */
122 	/* Prepare ESA */
123 	DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_PAGE1);	/* Select page 1 */
124 	/* Use the address from the serial EEPROM */
125 	for (i = 0; i < 6; i++)
126 		DP_IN(base, DP_P1_PAR0+i, dp->esa[i]);
127 	DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_PAGE0);	/* Select page 0 */
128 
129 	printf("NE2000 - %s ESA: %02x:%02x:%02x:%02x:%02x:%02x\n",
130 		"eeprom",
131 		dp->esa[0],
132 		dp->esa[1],
133 		dp->esa[2],
134 		dp->esa[3],
135 		dp->esa[4],
136 		dp->esa[5] );
137 
138 	memcpy(enetaddr, dp->esa, 6); /* Use MAC from serial EEPROM */
139 #endif	/* NE2000_BASIC_INIT */
140 	return true;
141 }
142 
143 static void
144 dp83902a_stop(void)
145 {
146 	dp83902a_priv_data_t *dp = &nic;
147 	u8 *base = dp->base;
148 
149 	DEBUG_FUNCTION();
150 
151 	DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_STOP);	/* Brutal */
152 	DP_OUT(base, DP_ISR, 0xFF);		/* Clear any pending interrupts */
153 	DP_OUT(base, DP_IMR, 0x00);		/* Disable all interrupts */
154 
155 	dp->running = false;
156 }
157 
158 /*
159  * This function is called to "start up" the interface. It may be called
160  * multiple times, even when the hardware is already running. It will be
161  * called whenever something "hardware oriented" changes and should leave
162  * the hardware ready to send/receive packets.
163  */
164 static void
165 dp83902a_start(u8 * enaddr)
166 {
167 	dp83902a_priv_data_t *dp = &nic;
168 	u8 *base = dp->base;
169 	int i;
170 
171 	debug("The MAC is %pM\n", enaddr);
172 
173 	DEBUG_FUNCTION();
174 
175 	DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_STOP); /* Brutal */
176 	DP_OUT(base, DP_DCR, DP_DCR_INIT);
177 	DP_OUT(base, DP_RBCH, 0);		/* Remote byte count */
178 	DP_OUT(base, DP_RBCL, 0);
179 	DP_OUT(base, DP_RCR, DP_RCR_MON);	/* Accept no packets */
180 	DP_OUT(base, DP_TCR, DP_TCR_LOCAL);	/* Transmitter [virtually] off */
181 	DP_OUT(base, DP_TPSR, dp->tx_buf1);	/* Transmitter start page */
182 	dp->tx1 = dp->tx2 = 0;
183 	dp->tx_next = dp->tx_buf1;
184 	dp->tx_started = false;
185 	dp->running = true;
186 	DP_OUT(base, DP_PSTART, dp->rx_buf_start); /* Receive ring start page */
187 	DP_OUT(base, DP_BNDRY, dp->rx_buf_end - 1); /* Receive ring boundary */
188 	DP_OUT(base, DP_PSTOP, dp->rx_buf_end);	/* Receive ring end page */
189 	dp->rx_next = dp->rx_buf_start - 1;
190 	dp->running = true;
191 	DP_OUT(base, DP_ISR, 0xFF);		/* Clear any pending interrupts */
192 	DP_OUT(base, DP_IMR, DP_IMR_All);	/* Enable all interrupts */
193 	DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_PAGE1 | DP_CR_STOP);	/* Select page 1 */
194 	DP_OUT(base, DP_P1_CURP, dp->rx_buf_start);	/* Current page - next free page for Rx */
195 	dp->running = true;
196 	for (i = 0; i < ETHER_ADDR_LEN; i++) {
197 		/* FIXME */
198 		/*((vu_short*)( base + ((DP_P1_PAR0 + i) * 2) +
199 		 * 0x1400)) = enaddr[i];*/
200 		DP_OUT(base, DP_P1_PAR0+i, enaddr[i]);
201 	}
202 	/* Enable and start device */
203 	DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_START);
204 	DP_OUT(base, DP_TCR, DP_TCR_NORMAL); /* Normal transmit operations */
205 	DP_OUT(base, DP_RCR, DP_RCR_AB); /* Accept broadcast, no errors, no multicast */
206 	dp->running = true;
207 }
208 
209 /*
210  * This routine is called to start the transmitter. It is split out from the
211  * data handling routine so it may be called either when data becomes first
212  * available or when an Tx interrupt occurs
213  */
214 
215 static void
216 dp83902a_start_xmit(int start_page, int len)
217 {
218 	dp83902a_priv_data_t *dp = (dp83902a_priv_data_t *) &nic;
219 	u8 *base = dp->base;
220 
221 	DEBUG_FUNCTION();
222 
223 #if DEBUG & 1
224 	printf("Tx pkt %d len %d\n", start_page, len);
225 	if (dp->tx_started)
226 		printf("TX already started?!?\n");
227 #endif
228 
229 	DP_OUT(base, DP_ISR, (DP_ISR_TxP | DP_ISR_TxE));
230 	DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_START);
231 	DP_OUT(base, DP_TBCL, len & 0xFF);
232 	DP_OUT(base, DP_TBCH, len >> 8);
233 	DP_OUT(base, DP_TPSR, start_page);
234 	DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_TXPKT | DP_CR_START);
235 
236 	dp->tx_started = true;
237 }
238 
239 /*
240  * This routine is called to send data to the hardware. It is known a-priori
241  * that there is free buffer space (dp->tx_next).
242  */
243 static void
244 dp83902a_send(u8 *data, int total_len, u32 key)
245 {
246 	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
247 	u8 *base = dp->base;
248 	int len, start_page, pkt_len, i, isr;
249 #if DEBUG & 4
250 	int dx;
251 #endif
252 
253 	DEBUG_FUNCTION();
254 
255 	len = pkt_len = total_len;
256 	if (pkt_len < IEEE_8023_MIN_FRAME)
257 		pkt_len = IEEE_8023_MIN_FRAME;
258 
259 	start_page = dp->tx_next;
260 	if (dp->tx_next == dp->tx_buf1) {
261 		dp->tx1 = start_page;
262 		dp->tx1_len = pkt_len;
263 		dp->tx1_key = key;
264 		dp->tx_next = dp->tx_buf2;
265 	} else {
266 		dp->tx2 = start_page;
267 		dp->tx2_len = pkt_len;
268 		dp->tx2_key = key;
269 		dp->tx_next = dp->tx_buf1;
270 	}
271 
272 #if DEBUG & 5
273 	printf("TX prep page %d len %d\n", start_page, pkt_len);
274 #endif
275 
276 	DP_OUT(base, DP_ISR, DP_ISR_RDC);	/* Clear end of DMA */
277 	{
278 		/*
279 		 * Dummy read. The manual sez something slightly different,
280 		 * but the code is extended a bit to do what Hitachi's monitor
281 		 * does (i.e., also read data).
282 		 */
283 
284 		__maybe_unused u16 tmp;
285 		int len = 1;
286 
287 		DP_OUT(base, DP_RSAL, 0x100 - len);
288 		DP_OUT(base, DP_RSAH, (start_page - 1) & 0xff);
289 		DP_OUT(base, DP_RBCL, len);
290 		DP_OUT(base, DP_RBCH, 0);
291 		DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_RDMA | DP_CR_START);
292 		DP_IN_DATA(dp->data, tmp);
293 	}
294 
295 #ifdef CYGHWR_NS_DP83902A_PLF_BROKEN_TX_DMA
296 	/*
297 	 * Stall for a bit before continuing to work around random data
298 	 * corruption problems on some platforms.
299 	 */
300 	CYGACC_CALL_IF_DELAY_US(1);
301 #endif
302 
303 	/* Send data to device buffer(s) */
304 	DP_OUT(base, DP_RSAL, 0);
305 	DP_OUT(base, DP_RSAH, start_page);
306 	DP_OUT(base, DP_RBCL, pkt_len & 0xFF);
307 	DP_OUT(base, DP_RBCH, pkt_len >> 8);
308 	DP_OUT(base, DP_CR, DP_CR_WDMA | DP_CR_START);
309 
310 	/* Put data into buffer */
311 #if DEBUG & 4
312 	printf(" sg buf %08lx len %08x\n ", (u32)data, len);
313 	dx = 0;
314 #endif
315 	while (len > 0) {
316 #if DEBUG & 4
317 		printf(" %02x", *data);
318 		if (0 == (++dx % 16)) printf("\n ");
319 #endif
320 
321 		DP_OUT_DATA(dp->data, *data++);
322 		len--;
323 	}
324 #if DEBUG & 4
325 	printf("\n");
326 #endif
327 	if (total_len < pkt_len) {
328 #if DEBUG & 4
329 		printf("  + %d bytes of padding\n", pkt_len - total_len);
330 #endif
331 		/* Padding to 802.3 length was required */
332 		for (i = total_len; i < pkt_len;) {
333 			i++;
334 			DP_OUT_DATA(dp->data, 0);
335 		}
336 	}
337 
338 #ifdef CYGHWR_NS_DP83902A_PLF_BROKEN_TX_DMA
339 	/*
340 	 * After last data write, delay for a bit before accessing the
341 	 * device again, or we may get random data corruption in the last
342 	 * datum (on some platforms).
343 	 */
344 	CYGACC_CALL_IF_DELAY_US(1);
345 #endif
346 
347 	/* Wait for DMA to complete */
348 	do {
349 		DP_IN(base, DP_ISR, isr);
350 	} while ((isr & DP_ISR_RDC) == 0);
351 
352 	/* Then disable DMA */
353 	DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_START);
354 
355 	/* Start transmit if not already going */
356 	if (!dp->tx_started) {
357 		if (start_page == dp->tx1) {
358 			dp->tx_int = 1; /* Expecting interrupt from BUF1 */
359 		} else {
360 			dp->tx_int = 2; /* Expecting interrupt from BUF2 */
361 		}
362 		dp83902a_start_xmit(start_page, pkt_len);
363 	}
364 }
365 
366 /*
367  * This function is called when a packet has been received. It's job is
368  * to prepare to unload the packet from the hardware. Once the length of
369  * the packet is known, the upper layer of the driver can be told. When
370  * the upper layer is ready to unload the packet, the internal function
371  * 'dp83902a_recv' will be called to actually fetch it from the hardware.
372  */
373 static void
374 dp83902a_RxEvent(void)
375 {
376 	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
377 	u8 *base = dp->base;
378 	__maybe_unused u8 rsr;
379 	u8 rcv_hdr[4];
380 	int i, len, pkt, cur;
381 
382 	DEBUG_FUNCTION();
383 
384 	DP_IN(base, DP_RSR, rsr);
385 	while (true) {
386 		/* Read incoming packet header */
387 		DP_OUT(base, DP_CR, DP_CR_PAGE1 | DP_CR_NODMA | DP_CR_START);
388 		DP_IN(base, DP_P1_CURP, cur);
389 		DP_OUT(base, DP_P1_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_START);
390 		DP_IN(base, DP_BNDRY, pkt);
391 
392 		pkt += 1;
393 		if (pkt == dp->rx_buf_end)
394 			pkt = dp->rx_buf_start;
395 
396 		if (pkt == cur) {
397 			break;
398 		}
399 		DP_OUT(base, DP_RBCL, sizeof(rcv_hdr));
400 		DP_OUT(base, DP_RBCH, 0);
401 		DP_OUT(base, DP_RSAL, 0);
402 		DP_OUT(base, DP_RSAH, pkt);
403 		if (dp->rx_next == pkt) {
404 			if (cur == dp->rx_buf_start)
405 				DP_OUT(base, DP_BNDRY, dp->rx_buf_end - 1);
406 			else
407 				DP_OUT(base, DP_BNDRY, cur - 1); /* Update pointer */
408 			return;
409 		}
410 		dp->rx_next = pkt;
411 		DP_OUT(base, DP_ISR, DP_ISR_RDC); /* Clear end of DMA */
412 		DP_OUT(base, DP_CR, DP_CR_RDMA | DP_CR_START);
413 #ifdef CYGHWR_NS_DP83902A_PLF_BROKEN_RX_DMA
414 		CYGACC_CALL_IF_DELAY_US(10);
415 #endif
416 
417 		/* read header (get data size)*/
418 		for (i = 0; i < sizeof(rcv_hdr);) {
419 			DP_IN_DATA(dp->data, rcv_hdr[i++]);
420 		}
421 
422 #if DEBUG & 5
423 		printf("rx hdr %02x %02x %02x %02x\n",
424 			rcv_hdr[0], rcv_hdr[1], rcv_hdr[2], rcv_hdr[3]);
425 #endif
426 		len = ((rcv_hdr[3] << 8) | rcv_hdr[2]) - sizeof(rcv_hdr);
427 
428 		/* data read */
429 		uboot_push_packet_len(len);
430 
431 		if (rcv_hdr[1] == dp->rx_buf_start)
432 			DP_OUT(base, DP_BNDRY, dp->rx_buf_end - 1);
433 		else
434 			DP_OUT(base, DP_BNDRY, rcv_hdr[1] - 1); /* Update pointer */
435 	}
436 }
437 
438 /*
439  * This function is called as a result of the "eth_drv_recv()" call above.
440  * It's job is to actually fetch data for a packet from the hardware once
441  * memory buffers have been allocated for the packet. Note that the buffers
442  * may come in pieces, using a scatter-gather list. This allows for more
443  * efficient processing in the upper layers of the stack.
444  */
445 static void
446 dp83902a_recv(u8 *data, int len)
447 {
448 	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
449 	u8 *base = dp->base;
450 	int i, mlen;
451 	u8 saved_char = 0;
452 	bool saved;
453 #if DEBUG & 4
454 	int dx;
455 #endif
456 
457 	DEBUG_FUNCTION();
458 
459 #if DEBUG & 5
460 	printf("Rx packet %d length %d\n", dp->rx_next, len);
461 #endif
462 
463 	/* Read incoming packet data */
464 	DP_OUT(base, DP_CR, DP_CR_PAGE0 | DP_CR_NODMA | DP_CR_START);
465 	DP_OUT(base, DP_RBCL, len & 0xFF);
466 	DP_OUT(base, DP_RBCH, len >> 8);
467 	DP_OUT(base, DP_RSAL, 4);		/* Past header */
468 	DP_OUT(base, DP_RSAH, dp->rx_next);
469 	DP_OUT(base, DP_ISR, DP_ISR_RDC); /* Clear end of DMA */
470 	DP_OUT(base, DP_CR, DP_CR_RDMA | DP_CR_START);
471 #ifdef CYGHWR_NS_DP83902A_PLF_BROKEN_RX_DMA
472 	CYGACC_CALL_IF_DELAY_US(10);
473 #endif
474 
475 	saved = false;
476 	for (i = 0; i < 1; i++) {
477 		if (data) {
478 			mlen = len;
479 #if DEBUG & 4
480 			printf(" sg buf %08lx len %08x \n", (u32) data, mlen);
481 			dx = 0;
482 #endif
483 			while (0 < mlen) {
484 				/* Saved byte from previous loop? */
485 				if (saved) {
486 					*data++ = saved_char;
487 					mlen--;
488 					saved = false;
489 					continue;
490 				}
491 
492 				{
493 					u8 tmp;
494 					DP_IN_DATA(dp->data, tmp);
495 #if DEBUG & 4
496 					printf(" %02x", tmp);
497 					if (0 == (++dx % 16)) printf("\n ");
498 #endif
499 					*data++ = tmp;
500 					mlen--;
501 				}
502 			}
503 #if DEBUG & 4
504 			printf("\n");
505 #endif
506 		}
507 	}
508 }
509 
510 static void
511 dp83902a_TxEvent(void)
512 {
513 	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
514 	u8 *base = dp->base;
515 	__maybe_unused u8 tsr;
516 	u32 key;
517 
518 	DEBUG_FUNCTION();
519 
520 	DP_IN(base, DP_TSR, tsr);
521 	if (dp->tx_int == 1) {
522 		key = dp->tx1_key;
523 		dp->tx1 = 0;
524 	} else {
525 		key = dp->tx2_key;
526 		dp->tx2 = 0;
527 	}
528 	/* Start next packet if one is ready */
529 	dp->tx_started = false;
530 	if (dp->tx1) {
531 		dp83902a_start_xmit(dp->tx1, dp->tx1_len);
532 		dp->tx_int = 1;
533 	} else if (dp->tx2) {
534 		dp83902a_start_xmit(dp->tx2, dp->tx2_len);
535 		dp->tx_int = 2;
536 	} else {
537 		dp->tx_int = 0;
538 	}
539 	/* Tell higher level we sent this packet */
540 	uboot_push_tx_done(key, 0);
541 }
542 
543 /*
544  * Read the tally counters to clear them. Called in response to a CNT
545  * interrupt.
546  */
547 static void
548 dp83902a_ClearCounters(void)
549 {
550 	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
551 	u8 *base = dp->base;
552 	__maybe_unused u8 cnt1, cnt2, cnt3;
553 
554 	DP_IN(base, DP_FER, cnt1);
555 	DP_IN(base, DP_CER, cnt2);
556 	DP_IN(base, DP_MISSED, cnt3);
557 	DP_OUT(base, DP_ISR, DP_ISR_CNT);
558 }
559 
560 /*
561  * Deal with an overflow condition. This code follows the procedure set
562  * out in section 7.0 of the datasheet.
563  */
564 static void
565 dp83902a_Overflow(void)
566 {
567 	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *)&nic;
568 	u8 *base = dp->base;
569 	u8 isr;
570 
571 	/* Issue a stop command and wait 1.6ms for it to complete. */
572 	DP_OUT(base, DP_CR, DP_CR_STOP | DP_CR_NODMA);
573 	CYGACC_CALL_IF_DELAY_US(1600);
574 
575 	/* Clear the remote byte counter registers. */
576 	DP_OUT(base, DP_RBCL, 0);
577 	DP_OUT(base, DP_RBCH, 0);
578 
579 	/* Enter loopback mode while we clear the buffer. */
580 	DP_OUT(base, DP_TCR, DP_TCR_LOCAL);
581 	DP_OUT(base, DP_CR, DP_CR_START | DP_CR_NODMA);
582 
583 	/*
584 	 * Read in as many packets as we can and acknowledge any and receive
585 	 * interrupts. Since the buffer has overflowed, a receive event of
586 	 * some kind will have occurred.
587 	 */
588 	dp83902a_RxEvent();
589 	DP_OUT(base, DP_ISR, DP_ISR_RxP|DP_ISR_RxE);
590 
591 	/* Clear the overflow condition and leave loopback mode. */
592 	DP_OUT(base, DP_ISR, DP_ISR_OFLW);
593 	DP_OUT(base, DP_TCR, DP_TCR_NORMAL);
594 
595 	/*
596 	 * If a transmit command was issued, but no transmit event has occurred,
597 	 * restart it here.
598 	 */
599 	DP_IN(base, DP_ISR, isr);
600 	if (dp->tx_started && !(isr & (DP_ISR_TxP|DP_ISR_TxE))) {
601 		DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_TXPKT | DP_CR_START);
602 	}
603 }
604 
605 static void
606 dp83902a_poll(void)
607 {
608 	struct dp83902a_priv_data *dp = (struct dp83902a_priv_data *) &nic;
609 	u8 *base = dp->base;
610 	u8 isr;
611 
612 	DP_OUT(base, DP_CR, DP_CR_NODMA | DP_CR_PAGE0 | DP_CR_START);
613 	DP_IN(base, DP_ISR, isr);
614 	while (0 != isr) {
615 		/*
616 		 * The CNT interrupt triggers when the MSB of one of the error
617 		 * counters is set. We don't much care about these counters, but
618 		 * we should read their values to reset them.
619 		 */
620 		if (isr & DP_ISR_CNT) {
621 			dp83902a_ClearCounters();
622 		}
623 		/*
624 		 * Check for overflow. It's a special case, since there's a
625 		 * particular procedure that must be followed to get back into
626 		 * a running state.a
627 		 */
628 		if (isr & DP_ISR_OFLW) {
629 			dp83902a_Overflow();
630 		} else {
631 			/*
632 			 * Other kinds of interrupts can be acknowledged simply by
633 			 * clearing the relevant bits of the ISR. Do that now, then
634 			 * handle the interrupts we care about.
635 			 */
636 			DP_OUT(base, DP_ISR, isr);	/* Clear set bits */
637 			if (!dp->running) break;	/* Is this necessary? */
638 			/*
639 			 * Check for tx_started on TX event since these may happen
640 			 * spuriously it seems.
641 			 */
642 			if (isr & (DP_ISR_TxP|DP_ISR_TxE) && dp->tx_started) {
643 				dp83902a_TxEvent();
644 			}
645 			if (isr & (DP_ISR_RxP|DP_ISR_RxE)) {
646 				dp83902a_RxEvent();
647 			}
648 		}
649 		DP_IN(base, DP_ISR, isr);
650 	}
651 }
652 
653 
654 /* U-Boot specific routines */
655 static u8 *pbuf = NULL;
656 
657 static int pkey = -1;
658 static int initialized = 0;
659 
660 void uboot_push_packet_len(int len) {
661 	PRINTK("pushed len = %d\n", len);
662 	if (len >= 2000) {
663 		printf("NE2000: packet too big\n");
664 		return;
665 	}
666 	dp83902a_recv(&pbuf[0], len);
667 
668 	/*Just pass it to the upper layer*/
669 	net_process_received_packet(&pbuf[0], len);
670 }
671 
672 void uboot_push_tx_done(int key, int val) {
673 	PRINTK("pushed key = %d\n", key);
674 	pkey = key;
675 }
676 
677 /**
678  * Setup the driver and init MAC address according to doc/README.enetaddr
679  * Called by ne2k_register() before registering the driver @eth layer
680  *
681  * @param struct ethdevice of this instance of the driver for dev->enetaddr
682  * @return 0 on success, -1 on error (causing caller to print error msg)
683  */
684 static int ne2k_setup_driver(struct eth_device *dev)
685 {
686 	PRINTK("### ne2k_setup_driver\n");
687 
688 	if (!pbuf) {
689 		pbuf = malloc(2000);
690 		if (!pbuf) {
691 			printf("Cannot allocate rx buffer\n");
692 			return -1;
693 		}
694 	}
695 
696 #ifdef CONFIG_DRIVER_NE2000_CCR
697 	{
698 		vu_char *p = (vu_char *) CONFIG_DRIVER_NE2000_CCR;
699 
700 		PRINTK("CCR before is %x\n", *p);
701 		*p = CONFIG_DRIVER_NE2000_VAL;
702 		PRINTK("CCR after is %x\n", *p);
703 	}
704 #endif
705 
706 	nic.base = (u8 *) CONFIG_DRIVER_NE2000_BASE;
707 
708 	nic.data = nic.base + DP_DATA;
709 	nic.tx_buf1 = START_PG;
710 	nic.tx_buf2 = START_PG2;
711 	nic.rx_buf_start = RX_START;
712 	nic.rx_buf_end = RX_END;
713 
714 	/*
715 	 * According to doc/README.enetaddr, drivers shall give priority
716 	 * to the MAC address value in the environment, so we do not read
717 	 * it from the prom or eeprom if it is specified in the environment.
718 	 */
719 	if (!eth_env_get_enetaddr("ethaddr", dev->enetaddr)) {
720 		/* If the MAC address is not in the environment, get it: */
721 		if (!get_prom(dev->enetaddr, nic.base)) /* get MAC from prom */
722 			dp83902a_init(dev->enetaddr);   /* fallback: seeprom */
723 		/* And write it into the environment otherwise eth_write_hwaddr
724 		 * returns -1 due to eth_env_get_enetaddr_by_index() failing,
725 		 * and this causes "Warning: failed to set MAC address", and
726 		 * cmd_bdinfo has no ethaddr value which it can show: */
727 		eth_env_set_enetaddr("ethaddr", dev->enetaddr);
728 	}
729 	return 0;
730 }
731 
732 static int ne2k_init(struct eth_device *dev, bd_t *bd)
733 {
734 	dp83902a_start(dev->enetaddr);
735 	initialized = 1;
736 	return 0;
737 }
738 
739 static void ne2k_halt(struct eth_device *dev)
740 {
741 	debug("### ne2k_halt\n");
742 	if(initialized)
743 		dp83902a_stop();
744 	initialized = 0;
745 }
746 
747 static int ne2k_recv(struct eth_device *dev)
748 {
749 	dp83902a_poll();
750 	return 1;
751 }
752 
753 static int ne2k_send(struct eth_device *dev, void *packet, int length)
754 {
755 	int tmo;
756 
757 	debug("### ne2k_send\n");
758 
759 	pkey = -1;
760 
761 	dp83902a_send((u8 *) packet, length, 666);
762 	tmo = get_timer (0) + TOUT * CONFIG_SYS_HZ;
763 	while(1) {
764 		dp83902a_poll();
765 		if (pkey != -1) {
766 			PRINTK("Packet sucesfully sent\n");
767 			return 0;
768 		}
769 		if (get_timer (0) >= tmo) {
770 			printf("transmission error (timoeut)\n");
771 			return 0;
772 		}
773 
774 	}
775 	return 0;
776 }
777 
778 /**
779  * Setup the driver for use and register it with the eth layer
780  * @return 0 on success, -1 on error (causing caller to print error msg)
781  */
782 int ne2k_register(void)
783 {
784 	struct eth_device *dev;
785 
786 	dev = calloc(sizeof(*dev), 1);
787 	if (dev == NULL)
788 		return -1;
789 
790 	if (ne2k_setup_driver(dev))
791 		return -1;
792 
793 	dev->init = ne2k_init;
794 	dev->halt = ne2k_halt;
795 	dev->send = ne2k_send;
796 	dev->recv = ne2k_recv;
797 
798 	strcpy(dev->name, "NE2000");
799 
800 	return eth_register(dev);
801 }
802