xref: /openbmc/u-boot/drivers/net/fec_mxc.c (revision 4f9a5b06)
1 /*
2  * (C) Copyright 2009 Ilya Yanok, Emcraft Systems Ltd <yanok@emcraft.com>
3  * (C) Copyright 2008,2009 Eric Jarrige <eric.jarrige@armadeus.org>
4  * (C) Copyright 2008 Armadeus Systems nc
5  * (C) Copyright 2007 Pengutronix, Sascha Hauer <s.hauer@pengutronix.de>
6  * (C) Copyright 2007 Pengutronix, Juergen Beisert <j.beisert@pengutronix.de>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 #include <malloc.h>
26 #include <net.h>
27 #include <miiphy.h>
28 #include "fec_mxc.h"
29 
30 #include <asm/arch/clock.h>
31 #include <asm/arch/imx-regs.h>
32 #include <asm/io.h>
33 #include <asm/errno.h>
34 
35 DECLARE_GLOBAL_DATA_PTR;
36 
37 #ifndef CONFIG_MII
38 #error "CONFIG_MII has to be defined!"
39 #endif
40 
41 #undef DEBUG
42 
43 struct nbuf {
44 	uint8_t data[1500];	/**< actual data */
45 	int length;		/**< actual length */
46 	int used;		/**< buffer in use or not */
47 	uint8_t head[16];	/**< MAC header(6 + 6 + 2) + 2(aligned) */
48 };
49 
50 struct fec_priv gfec = {
51 	.eth       = (struct ethernet_regs *)IMX_FEC_BASE,
52 	.xcv_type  = MII100,
53 	.rbd_base  = NULL,
54 	.rbd_index = 0,
55 	.tbd_base  = NULL,
56 	.tbd_index = 0,
57 	.bd        = NULL,
58 	.rdb_ptr   = NULL,
59 	.base_ptr  = NULL,
60 };
61 
62 /*
63  * MII-interface related functions
64  */
65 static int fec_miiphy_read(const char *dev, uint8_t phyAddr, uint8_t regAddr,
66 		uint16_t *retVal)
67 {
68 	struct eth_device *edev = eth_get_dev_by_name(dev);
69 	struct fec_priv *fec = (struct fec_priv *)edev->priv;
70 
71 	uint32_t reg;		/* convenient holder for the PHY register */
72 	uint32_t phy;		/* convenient holder for the PHY */
73 	uint32_t start;
74 
75 	/*
76 	 * reading from any PHY's register is done by properly
77 	 * programming the FEC's MII data register.
78 	 */
79 	writel(FEC_IEVENT_MII, &fec->eth->ievent);
80 	reg = regAddr << FEC_MII_DATA_RA_SHIFT;
81 	phy = phyAddr << FEC_MII_DATA_PA_SHIFT;
82 
83 	writel(FEC_MII_DATA_ST | FEC_MII_DATA_OP_RD | FEC_MII_DATA_TA |
84 			phy | reg, &fec->eth->mii_data);
85 
86 	/*
87 	 * wait for the related interrupt
88 	 */
89 	start = get_timer_masked();
90 	while (!(readl(&fec->eth->ievent) & FEC_IEVENT_MII)) {
91 		if (get_timer(start) > (CONFIG_SYS_HZ / 1000)) {
92 			printf("Read MDIO failed...\n");
93 			return -1;
94 		}
95 	}
96 
97 	/*
98 	 * clear mii interrupt bit
99 	 */
100 	writel(FEC_IEVENT_MII, &fec->eth->ievent);
101 
102 	/*
103 	 * it's now safe to read the PHY's register
104 	 */
105 	*retVal = readl(&fec->eth->mii_data);
106 	debug("fec_miiphy_read: phy: %02x reg:%02x val:%#x\n", phyAddr,
107 			regAddr, *retVal);
108 	return 0;
109 }
110 
111 static void fec_mii_setspeed(struct fec_priv *fec)
112 {
113 	/*
114 	 * Set MII_SPEED = (1/(mii_speed * 2)) * System Clock
115 	 * and do not drop the Preamble.
116 	 */
117 	writel((((imx_get_fecclk() / 1000000) + 2) / 5) << 1,
118 			&fec->eth->mii_speed);
119 	debug("fec_init: mii_speed %#lx\n",
120 			fec->eth->mii_speed);
121 }
122 static int fec_miiphy_write(const char *dev, uint8_t phyAddr, uint8_t regAddr,
123 		uint16_t data)
124 {
125 	struct eth_device *edev = eth_get_dev_by_name(dev);
126 	struct fec_priv *fec = (struct fec_priv *)edev->priv;
127 
128 	uint32_t reg;		/* convenient holder for the PHY register */
129 	uint32_t phy;		/* convenient holder for the PHY */
130 	uint32_t start;
131 
132 	reg = regAddr << FEC_MII_DATA_RA_SHIFT;
133 	phy = phyAddr << FEC_MII_DATA_PA_SHIFT;
134 
135 	writel(FEC_MII_DATA_ST | FEC_MII_DATA_OP_WR |
136 		FEC_MII_DATA_TA | phy | reg | data, &fec->eth->mii_data);
137 
138 	/*
139 	 * wait for the MII interrupt
140 	 */
141 	start = get_timer_masked();
142 	while (!(readl(&fec->eth->ievent) & FEC_IEVENT_MII)) {
143 		if (get_timer(start) > (CONFIG_SYS_HZ / 1000)) {
144 			printf("Write MDIO failed...\n");
145 			return -1;
146 		}
147 	}
148 
149 	/*
150 	 * clear MII interrupt bit
151 	 */
152 	writel(FEC_IEVENT_MII, &fec->eth->ievent);
153 	debug("fec_miiphy_write: phy: %02x reg:%02x val:%#x\n", phyAddr,
154 			regAddr, data);
155 
156 	return 0;
157 }
158 
159 static int miiphy_restart_aneg(struct eth_device *dev)
160 {
161 	/*
162 	 * Wake up from sleep if necessary
163 	 * Reset PHY, then delay 300ns
164 	 */
165 #ifdef CONFIG_MX27
166 	miiphy_write(dev->name, CONFIG_FEC_MXC_PHYADDR, MII_DCOUNTER, 0x00FF);
167 #endif
168 	miiphy_write(dev->name, CONFIG_FEC_MXC_PHYADDR, MII_BMCR,
169 			BMCR_RESET);
170 	udelay(1000);
171 
172 	/*
173 	 * Set the auto-negotiation advertisement register bits
174 	 */
175 	miiphy_write(dev->name, CONFIG_FEC_MXC_PHYADDR, MII_ADVERTISE,
176 			LPA_100FULL | LPA_100HALF | LPA_10FULL |
177 			LPA_10HALF | PHY_ANLPAR_PSB_802_3);
178 	miiphy_write(dev->name, CONFIG_FEC_MXC_PHYADDR, MII_BMCR,
179 			BMCR_ANENABLE | BMCR_ANRESTART);
180 
181 	return 0;
182 }
183 
184 static int miiphy_wait_aneg(struct eth_device *dev)
185 {
186 	uint32_t start;
187 	uint16_t status;
188 
189 	/*
190 	 * Wait for AN completion
191 	 */
192 	start = get_timer_masked();
193 	do {
194 		if (get_timer(start) > (CONFIG_SYS_HZ * 5)) {
195 			printf("%s: Autonegotiation timeout\n", dev->name);
196 			return -1;
197 		}
198 
199 		if (miiphy_read(dev->name, CONFIG_FEC_MXC_PHYADDR,
200 					MII_BMSR, &status)) {
201 			printf("%s: Autonegotiation failed. status: 0x%04x\n",
202 					dev->name, status);
203 			return -1;
204 		}
205 	} while (!(status & BMSR_LSTATUS));
206 
207 	return 0;
208 }
209 static int fec_rx_task_enable(struct fec_priv *fec)
210 {
211 	writel(1 << 24, &fec->eth->r_des_active);
212 	return 0;
213 }
214 
215 static int fec_rx_task_disable(struct fec_priv *fec)
216 {
217 	return 0;
218 }
219 
220 static int fec_tx_task_enable(struct fec_priv *fec)
221 {
222 	writel(1 << 24, &fec->eth->x_des_active);
223 	return 0;
224 }
225 
226 static int fec_tx_task_disable(struct fec_priv *fec)
227 {
228 	return 0;
229 }
230 
231 /**
232  * Initialize receive task's buffer descriptors
233  * @param[in] fec all we know about the device yet
234  * @param[in] count receive buffer count to be allocated
235  * @param[in] size size of each receive buffer
236  * @return 0 on success
237  *
238  * For this task we need additional memory for the data buffers. And each
239  * data buffer requires some alignment. Thy must be aligned to a specific
240  * boundary each (DB_DATA_ALIGNMENT).
241  */
242 static int fec_rbd_init(struct fec_priv *fec, int count, int size)
243 {
244 	int ix;
245 	uint32_t p = 0;
246 
247 	/* reserve data memory and consider alignment */
248 	if (fec->rdb_ptr == NULL)
249 		fec->rdb_ptr = malloc(size * count + DB_DATA_ALIGNMENT);
250 	p = (uint32_t)fec->rdb_ptr;
251 	if (!p) {
252 		puts("fec_mxc: not enough malloc memory\n");
253 		return -ENOMEM;
254 	}
255 	memset((void *)p, 0, size * count + DB_DATA_ALIGNMENT);
256 	p += DB_DATA_ALIGNMENT-1;
257 	p &= ~(DB_DATA_ALIGNMENT-1);
258 
259 	for (ix = 0; ix < count; ix++) {
260 		writel(p, &fec->rbd_base[ix].data_pointer);
261 		p += size;
262 		writew(FEC_RBD_EMPTY, &fec->rbd_base[ix].status);
263 		writew(0, &fec->rbd_base[ix].data_length);
264 	}
265 	/*
266 	 * mark the last RBD to close the ring
267 	 */
268 	writew(FEC_RBD_WRAP | FEC_RBD_EMPTY, &fec->rbd_base[ix - 1].status);
269 	fec->rbd_index = 0;
270 
271 	return 0;
272 }
273 
274 /**
275  * Initialize transmit task's buffer descriptors
276  * @param[in] fec all we know about the device yet
277  *
278  * Transmit buffers are created externally. We only have to init the BDs here.\n
279  * Note: There is a race condition in the hardware. When only one BD is in
280  * use it must be marked with the WRAP bit to use it for every transmitt.
281  * This bit in combination with the READY bit results into double transmit
282  * of each data buffer. It seems the state machine checks READY earlier then
283  * resetting it after the first transfer.
284  * Using two BDs solves this issue.
285  */
286 static void fec_tbd_init(struct fec_priv *fec)
287 {
288 	writew(0x0000, &fec->tbd_base[0].status);
289 	writew(FEC_TBD_WRAP, &fec->tbd_base[1].status);
290 	fec->tbd_index = 0;
291 }
292 
293 /**
294  * Mark the given read buffer descriptor as free
295  * @param[in] last 1 if this is the last buffer descriptor in the chain, else 0
296  * @param[in] pRbd buffer descriptor to mark free again
297  */
298 static void fec_rbd_clean(int last, struct fec_bd *pRbd)
299 {
300 	/*
301 	 * Reset buffer descriptor as empty
302 	 */
303 	if (last)
304 		writew(FEC_RBD_WRAP | FEC_RBD_EMPTY, &pRbd->status);
305 	else
306 		writew(FEC_RBD_EMPTY, &pRbd->status);
307 	/*
308 	 * no data in it
309 	 */
310 	writew(0, &pRbd->data_length);
311 }
312 
313 static int fec_get_hwaddr(struct eth_device *dev, unsigned char *mac)
314 {
315 	imx_get_mac_from_fuse(mac);
316 	return !is_valid_ether_addr(mac);
317 }
318 
319 static int fec_set_hwaddr(struct eth_device *dev)
320 {
321 	uchar *mac = dev->enetaddr;
322 	struct fec_priv *fec = (struct fec_priv *)dev->priv;
323 
324 	writel(0, &fec->eth->iaddr1);
325 	writel(0, &fec->eth->iaddr2);
326 	writel(0, &fec->eth->gaddr1);
327 	writel(0, &fec->eth->gaddr2);
328 
329 	/*
330 	 * Set physical address
331 	 */
332 	writel((mac[0] << 24) + (mac[1] << 16) + (mac[2] << 8) + mac[3],
333 			&fec->eth->paddr1);
334 	writel((mac[4] << 24) + (mac[5] << 16) + 0x8808, &fec->eth->paddr2);
335 
336 	return 0;
337 }
338 
339 /**
340  * Start the FEC engine
341  * @param[in] dev Our device to handle
342  */
343 static int fec_open(struct eth_device *edev)
344 {
345 	struct fec_priv *fec = (struct fec_priv *)edev->priv;
346 
347 	debug("fec_open: fec_open(dev)\n");
348 	/* full-duplex, heartbeat disabled */
349 	writel(1 << 2, &fec->eth->x_cntrl);
350 	fec->rbd_index = 0;
351 
352 	/*
353 	 * Enable FEC-Lite controller
354 	 */
355 	writel(readl(&fec->eth->ecntrl) | FEC_ECNTRL_ETHER_EN,
356 		&fec->eth->ecntrl);
357 #ifdef CONFIG_MX25
358 	udelay(100);
359 	/*
360 	 * setup the MII gasket for RMII mode
361 	 */
362 
363 	/* disable the gasket */
364 	writew(0, &fec->eth->miigsk_enr);
365 
366 	/* wait for the gasket to be disabled */
367 	while (readw(&fec->eth->miigsk_enr) & MIIGSK_ENR_READY)
368 		udelay(2);
369 
370 	/* configure gasket for RMII, 50 MHz, no loopback, and no echo */
371 	writew(MIIGSK_CFGR_IF_MODE_RMII, &fec->eth->miigsk_cfgr);
372 
373 	/* re-enable the gasket */
374 	writew(MIIGSK_ENR_EN, &fec->eth->miigsk_enr);
375 
376 	/* wait until MII gasket is ready */
377 	int max_loops = 10;
378 	while ((readw(&fec->eth->miigsk_enr) & MIIGSK_ENR_READY) == 0) {
379 		if (--max_loops <= 0) {
380 			printf("WAIT for MII Gasket ready timed out\n");
381 			break;
382 		}
383 	}
384 #endif
385 
386 	miiphy_wait_aneg(edev);
387 	miiphy_speed(edev->name, CONFIG_FEC_MXC_PHYADDR);
388 	miiphy_duplex(edev->name, CONFIG_FEC_MXC_PHYADDR);
389 
390 	/*
391 	 * Enable SmartDMA receive task
392 	 */
393 	fec_rx_task_enable(fec);
394 
395 	udelay(100000);
396 	return 0;
397 }
398 
399 static int fec_init(struct eth_device *dev, bd_t* bd)
400 {
401 	uint32_t base;
402 	struct fec_priv *fec = (struct fec_priv *)dev->priv;
403 
404 	/* Initialize MAC address */
405 	fec_set_hwaddr(dev);
406 
407 	/*
408 	 * reserve memory for both buffer descriptor chains at once
409 	 * Datasheet forces the startaddress of each chain is 16 byte
410 	 * aligned
411 	 */
412 	if (fec->base_ptr == NULL)
413 		fec->base_ptr = malloc((2 + FEC_RBD_NUM) *
414 				sizeof(struct fec_bd) + DB_ALIGNMENT);
415 	base = (uint32_t)fec->base_ptr;
416 	if (!base) {
417 		puts("fec_mxc: not enough malloc memory\n");
418 		return -ENOMEM;
419 	}
420 	memset((void *)base, 0, (2 + FEC_RBD_NUM) *
421 			sizeof(struct fec_bd) + DB_ALIGNMENT);
422 	base += (DB_ALIGNMENT-1);
423 	base &= ~(DB_ALIGNMENT-1);
424 
425 	fec->rbd_base = (struct fec_bd *)base;
426 
427 	base += FEC_RBD_NUM * sizeof(struct fec_bd);
428 
429 	fec->tbd_base = (struct fec_bd *)base;
430 
431 	/*
432 	 * Set interrupt mask register
433 	 */
434 	writel(0x00000000, &fec->eth->imask);
435 
436 	/*
437 	 * Clear FEC-Lite interrupt event register(IEVENT)
438 	 */
439 	writel(0xffffffff, &fec->eth->ievent);
440 
441 
442 	/*
443 	 * Set FEC-Lite receive control register(R_CNTRL):
444 	 */
445 	if (fec->xcv_type == SEVENWIRE) {
446 		/*
447 		 * Frame length=1518; 7-wire mode
448 		 */
449 		writel(0x05ee0020, &fec->eth->r_cntrl);	/* FIXME 0x05ee0000 */
450 	} else {
451 		/*
452 		 * Frame length=1518; MII mode;
453 		 */
454 		writel(0x05ee0024, &fec->eth->r_cntrl);	/* FIXME 0x05ee0004 */
455 
456 		fec_mii_setspeed(fec);
457 	}
458 	/*
459 	 * Set Opcode/Pause Duration Register
460 	 */
461 	writel(0x00010020, &fec->eth->op_pause);	/* FIXME 0xffff0020; */
462 	writel(0x2, &fec->eth->x_wmrk);
463 	/*
464 	 * Set multicast address filter
465 	 */
466 	writel(0x00000000, &fec->eth->gaddr1);
467 	writel(0x00000000, &fec->eth->gaddr2);
468 
469 
470 	/* clear MIB RAM */
471 	long *mib_ptr = (long *)(IMX_FEC_BASE + 0x200);
472 	while (mib_ptr <= (long *)(IMX_FEC_BASE + 0x2FC))
473 		*mib_ptr++ = 0;
474 
475 	/* FIFO receive start register */
476 	writel(0x520, &fec->eth->r_fstart);
477 
478 	/* size and address of each buffer */
479 	writel(FEC_MAX_PKT_SIZE, &fec->eth->emrbr);
480 	writel((uint32_t)fec->tbd_base, &fec->eth->etdsr);
481 	writel((uint32_t)fec->rbd_base, &fec->eth->erdsr);
482 
483 	/*
484 	 * Initialize RxBD/TxBD rings
485 	 */
486 	if (fec_rbd_init(fec, FEC_RBD_NUM, FEC_MAX_PKT_SIZE) < 0) {
487 		free(fec->base_ptr);
488 		fec->base_ptr = NULL;
489 		return -ENOMEM;
490 	}
491 	fec_tbd_init(fec);
492 
493 
494 	if (fec->xcv_type != SEVENWIRE)
495 		miiphy_restart_aneg(dev);
496 
497 	fec_open(dev);
498 	return 0;
499 }
500 
501 /**
502  * Halt the FEC engine
503  * @param[in] dev Our device to handle
504  */
505 static void fec_halt(struct eth_device *dev)
506 {
507 	struct fec_priv *fec = &gfec;
508 	int counter = 0xffff;
509 
510 	/*
511 	 * issue graceful stop command to the FEC transmitter if necessary
512 	 */
513 	writel(FEC_TCNTRL_GTS | readl(&fec->eth->x_cntrl),
514 			&fec->eth->x_cntrl);
515 
516 	debug("eth_halt: wait for stop regs\n");
517 	/*
518 	 * wait for graceful stop to register
519 	 */
520 	while ((counter--) && (!(readl(&fec->eth->ievent) & FEC_IEVENT_GRA)))
521 		udelay(1);
522 
523 	/*
524 	 * Disable SmartDMA tasks
525 	 */
526 	fec_tx_task_disable(fec);
527 	fec_rx_task_disable(fec);
528 
529 	/*
530 	 * Disable the Ethernet Controller
531 	 * Note: this will also reset the BD index counter!
532 	 */
533 	writel(readl(&fec->eth->ecntrl) & ~FEC_ECNTRL_ETHER_EN,
534 			&fec->eth->ecntrl);
535 	fec->rbd_index = 0;
536 	fec->tbd_index = 0;
537 	debug("eth_halt: done\n");
538 }
539 
540 /**
541  * Transmit one frame
542  * @param[in] dev Our ethernet device to handle
543  * @param[in] packet Pointer to the data to be transmitted
544  * @param[in] length Data count in bytes
545  * @return 0 on success
546  */
547 static int fec_send(struct eth_device *dev, volatile void* packet, int length)
548 {
549 	unsigned int status;
550 
551 	/*
552 	 * This routine transmits one frame.  This routine only accepts
553 	 * 6-byte Ethernet addresses.
554 	 */
555 	struct fec_priv *fec = (struct fec_priv *)dev->priv;
556 
557 	/*
558 	 * Check for valid length of data.
559 	 */
560 	if ((length > 1500) || (length <= 0)) {
561 		printf("Payload (%d) too large\n", length);
562 		return -1;
563 	}
564 
565 	/*
566 	 * Setup the transmit buffer
567 	 * Note: We are always using the first buffer for transmission,
568 	 * the second will be empty and only used to stop the DMA engine
569 	 */
570 	writew(length, &fec->tbd_base[fec->tbd_index].data_length);
571 	writel((uint32_t)packet, &fec->tbd_base[fec->tbd_index].data_pointer);
572 	/*
573 	 * update BD's status now
574 	 * This block:
575 	 * - is always the last in a chain (means no chain)
576 	 * - should transmitt the CRC
577 	 * - might be the last BD in the list, so the address counter should
578 	 *   wrap (-> keep the WRAP flag)
579 	 */
580 	status = readw(&fec->tbd_base[fec->tbd_index].status) & FEC_TBD_WRAP;
581 	status |= FEC_TBD_LAST | FEC_TBD_TC | FEC_TBD_READY;
582 	writew(status, &fec->tbd_base[fec->tbd_index].status);
583 
584 	/*
585 	 * Enable SmartDMA transmit task
586 	 */
587 	fec_tx_task_enable(fec);
588 
589 	/*
590 	 * wait until frame is sent .
591 	 */
592 	while (readw(&fec->tbd_base[fec->tbd_index].status) & FEC_TBD_READY) {
593 		udelay(1);
594 	}
595 	debug("fec_send: status 0x%x index %d\n",
596 			readw(&fec->tbd_base[fec->tbd_index].status),
597 			fec->tbd_index);
598 	/* for next transmission use the other buffer */
599 	if (fec->tbd_index)
600 		fec->tbd_index = 0;
601 	else
602 		fec->tbd_index = 1;
603 
604 	return 0;
605 }
606 
607 /**
608  * Pull one frame from the card
609  * @param[in] dev Our ethernet device to handle
610  * @return Length of packet read
611  */
612 static int fec_recv(struct eth_device *dev)
613 {
614 	struct fec_priv *fec = (struct fec_priv *)dev->priv;
615 	struct fec_bd *rbd = &fec->rbd_base[fec->rbd_index];
616 	unsigned long ievent;
617 	int frame_length, len = 0;
618 	struct nbuf *frame;
619 	uint16_t bd_status;
620 	uchar buff[FEC_MAX_PKT_SIZE];
621 
622 	/*
623 	 * Check if any critical events have happened
624 	 */
625 	ievent = readl(&fec->eth->ievent);
626 	writel(ievent, &fec->eth->ievent);
627 	debug("fec_recv: ievent 0x%x\n", ievent);
628 	if (ievent & FEC_IEVENT_BABR) {
629 		fec_halt(dev);
630 		fec_init(dev, fec->bd);
631 		printf("some error: 0x%08lx\n", ievent);
632 		return 0;
633 	}
634 	if (ievent & FEC_IEVENT_HBERR) {
635 		/* Heartbeat error */
636 		writel(0x00000001 | readl(&fec->eth->x_cntrl),
637 				&fec->eth->x_cntrl);
638 	}
639 	if (ievent & FEC_IEVENT_GRA) {
640 		/* Graceful stop complete */
641 		if (readl(&fec->eth->x_cntrl) & 0x00000001) {
642 			fec_halt(dev);
643 			writel(~0x00000001 & readl(&fec->eth->x_cntrl),
644 					&fec->eth->x_cntrl);
645 			fec_init(dev, fec->bd);
646 		}
647 	}
648 
649 	/*
650 	 * ensure reading the right buffer status
651 	 */
652 	bd_status = readw(&rbd->status);
653 	debug("fec_recv: status 0x%x\n", bd_status);
654 
655 	if (!(bd_status & FEC_RBD_EMPTY)) {
656 		if ((bd_status & FEC_RBD_LAST) && !(bd_status & FEC_RBD_ERR) &&
657 			((readw(&rbd->data_length) - 4) > 14)) {
658 			/*
659 			 * Get buffer address and size
660 			 */
661 			frame = (struct nbuf *)readl(&rbd->data_pointer);
662 			frame_length = readw(&rbd->data_length) - 4;
663 			/*
664 			 *  Fill the buffer and pass it to upper layers
665 			 */
666 			memcpy(buff, frame->data, frame_length);
667 			NetReceive(buff, frame_length);
668 			len = frame_length;
669 		} else {
670 			if (bd_status & FEC_RBD_ERR)
671 				printf("error frame: 0x%08lx 0x%08x\n",
672 						(ulong)rbd->data_pointer,
673 						bd_status);
674 		}
675 		/*
676 		 * free the current buffer, restart the engine
677 		 * and move forward to the next buffer
678 		 */
679 		fec_rbd_clean(fec->rbd_index == (FEC_RBD_NUM - 1) ? 1 : 0, rbd);
680 		fec_rx_task_enable(fec);
681 		fec->rbd_index = (fec->rbd_index + 1) % FEC_RBD_NUM;
682 	}
683 	debug("fec_recv: stop\n");
684 
685 	return len;
686 }
687 
688 static int fec_probe(bd_t *bd)
689 {
690 	struct eth_device *edev;
691 	struct fec_priv *fec = &gfec;
692 	unsigned char ethaddr[6];
693 
694 	/* create and fill edev struct */
695 	edev = (struct eth_device *)malloc(sizeof(struct eth_device));
696 	if (!edev) {
697 		puts("fec_mxc: not enough malloc memory\n");
698 		return -ENOMEM;
699 	}
700 	memset(edev, 0, sizeof(*edev));
701 	edev->priv = fec;
702 	edev->init = fec_init;
703 	edev->send = fec_send;
704 	edev->recv = fec_recv;
705 	edev->halt = fec_halt;
706 	edev->write_hwaddr = fec_set_hwaddr;
707 
708 	fec->eth = (struct ethernet_regs *)IMX_FEC_BASE;
709 	fec->bd = bd;
710 
711 	fec->xcv_type = MII100;
712 
713 	/* Reset chip. */
714 	writel(readl(&fec->eth->ecntrl) | FEC_ECNTRL_RESET, &fec->eth->ecntrl);
715 	while (readl(&fec->eth->ecntrl) & 1)
716 		udelay(10);
717 
718 	/*
719 	 * Set interrupt mask register
720 	 */
721 	writel(0x00000000, &fec->eth->imask);
722 
723 	/*
724 	 * Clear FEC-Lite interrupt event register(IEVENT)
725 	 */
726 	writel(0xffffffff, &fec->eth->ievent);
727 
728 	/*
729 	 * Set FEC-Lite receive control register(R_CNTRL):
730 	 */
731 	/*
732 	 * Frame length=1518; MII mode;
733 	 */
734 	writel(0x05ee0024, &fec->eth->r_cntrl);	/* FIXME 0x05ee0004 */
735 	fec_mii_setspeed(fec);
736 
737 	sprintf(edev->name, "FEC");
738 
739 	miiphy_register(edev->name, fec_miiphy_read, fec_miiphy_write);
740 
741 	eth_register(edev);
742 
743 	if (fec_get_hwaddr(edev, ethaddr) == 0) {
744 		printf("got MAC address from fuse: %pM\n", ethaddr);
745 		memcpy(edev->enetaddr, ethaddr, 6);
746 	}
747 
748 	return 0;
749 }
750 
751 int fecmxc_initialize(bd_t *bd)
752 {
753 	int lout = 1;
754 
755 	debug("eth_init: fec_probe(bd)\n");
756 	lout = fec_probe(bd);
757 
758 	return lout;
759 }
760