xref: /rk3399_rockchip-uboot/drivers/net/enc28j60.c (revision eee479cf6a4046d25f8032c402355d9fc237fb70)
1 /*
2  * (C) Copyright 2010
3  * Reinhard Meyer, EMK Elektronik, reinhard.meyer@emk-elektronik.de
4  * Martin Krause, Martin.Krause@tqs.de
5  * reworked original enc28j60.c
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <net.h>
12 #include <spi.h>
13 #include <malloc.h>
14 #include <netdev.h>
15 #include <miiphy.h>
16 #include "enc28j60.h"
17 
18 /*
19  * IMPORTANT: spi_claim_bus() and spi_release_bus()
20  * are called at begin and end of each of the following functions:
21  * enc_miiphy_read(), enc_miiphy_write(), enc_write_hwaddr(),
22  * enc_init(), enc_recv(), enc_send(), enc_halt()
23  * ALL other functions assume that the bus has already been claimed!
24  * Since NetReceive() might call enc_send() in return, the bus must be
25  * released, NetReceive() called and claimed again.
26  */
27 
28 /*
29  * Controller memory layout.
30  * We only allow 1 frame for transmission and reserve the rest
31  * for reception to handle as many broadcast packets as possible.
32  * Also use the memory from 0x0000 for receiver buffer. See errata pt. 5
33  * 0x0000 - 0x19ff 6656 bytes receive buffer
34  * 0x1a00 - 0x1fff 1536 bytes transmit buffer =
35  * control(1)+frame(1518)+status(7)+reserve(10).
36  */
37 #define ENC_RX_BUF_START	0x0000
38 #define ENC_RX_BUF_END		0x19ff
39 #define ENC_TX_BUF_START	0x1a00
40 #define ENC_TX_BUF_END		0x1fff
41 #define ENC_MAX_FRM_LEN		1518
42 #define RX_RESET_COUNTER	1000
43 
44 /*
45  * For non data transfer functions, like phy read/write, set hwaddr, init
46  * we do not need a full, time consuming init including link ready wait.
47  * This enum helps to bring the chip through the minimum necessary inits.
48  */
49 enum enc_initstate {none=0, setupdone, linkready};
50 typedef struct enc_device {
51 	struct eth_device	*dev;	/* back pointer */
52 	struct spi_slave	*slave;
53 	int			rx_reset_counter;
54 	u16			next_pointer;
55 	u8			bank;	/* current bank in enc28j60 */
56 	enum enc_initstate	initstate;
57 } enc_dev_t;
58 
59 /*
60  * enc_bset:		set bits in a common register
61  * enc_bclr:		clear bits in a common register
62  *
63  * making the reg parameter u8 will give a compile time warning if the
64  * functions are called with a register not accessible in all Banks
65  */
66 static void enc_bset(enc_dev_t *enc, const u8 reg, const u8 data)
67 {
68 	u8 dout[2];
69 
70 	dout[0] = CMD_BFS(reg);
71 	dout[1] = data;
72 	spi_xfer(enc->slave, 2 * 8, dout, NULL,
73 		SPI_XFER_BEGIN | SPI_XFER_END);
74 }
75 
76 static void enc_bclr(enc_dev_t *enc, const u8 reg, const u8 data)
77 {
78 	u8 dout[2];
79 
80 	dout[0] = CMD_BFC(reg);
81 	dout[1] = data;
82 	spi_xfer(enc->slave, 2 * 8, dout, NULL,
83 		SPI_XFER_BEGIN | SPI_XFER_END);
84 }
85 
86 /*
87  * high byte of the register contains bank number:
88  * 0: no bank switch necessary
89  * 1: switch to bank 0
90  * 2: switch to bank 1
91  * 3: switch to bank 2
92  * 4: switch to bank 3
93  */
94 static void enc_set_bank(enc_dev_t *enc, const u16 reg)
95 {
96 	u8 newbank = reg >> 8;
97 
98 	if (newbank == 0 || newbank == enc->bank)
99 		return;
100 	switch (newbank) {
101 	case 1:
102 		enc_bclr(enc, CTL_REG_ECON1,
103 			ENC_ECON1_BSEL0 | ENC_ECON1_BSEL1);
104 		break;
105 	case 2:
106 		enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_BSEL0);
107 		enc_bclr(enc, CTL_REG_ECON1, ENC_ECON1_BSEL1);
108 		break;
109 	case 3:
110 		enc_bclr(enc, CTL_REG_ECON1, ENC_ECON1_BSEL0);
111 		enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_BSEL1);
112 		break;
113 	case 4:
114 		enc_bset(enc, CTL_REG_ECON1,
115 			ENC_ECON1_BSEL0 | ENC_ECON1_BSEL1);
116 		break;
117 	}
118 	enc->bank = newbank;
119 }
120 
121 /*
122  * local functions to access SPI
123  *
124  * reg: register inside ENC28J60
125  * data: 8/16 bits to write
126  * c: number of retries
127  *
128  * enc_r8:		read 8 bits
129  * enc_r16:		read 16 bits
130  * enc_w8:		write 8 bits
131  * enc_w16:		write 16 bits
132  * enc_w8_retry:	write 8 bits, verify and retry
133  * enc_rbuf:		read from ENC28J60 into buffer
134  * enc_wbuf:		write from buffer into ENC28J60
135  */
136 
137 /*
138  * MAC and MII registers need a 3 byte SPI transfer to read,
139  * all other registers need a 2 byte SPI transfer.
140  */
141 static int enc_reg2nbytes(const u16 reg)
142 {
143 	/* check if MAC or MII register */
144 	return ((reg >= CTL_REG_MACON1 && reg <= CTL_REG_MIRDH) ||
145 		(reg >= CTL_REG_MAADR1 && reg <= CTL_REG_MAADR4) ||
146 		(reg == CTL_REG_MISTAT)) ? 3 : 2;
147 }
148 
149 /*
150  * Read a byte register
151  */
152 static u8 enc_r8(enc_dev_t *enc, const u16 reg)
153 {
154 	u8 dout[3];
155 	u8 din[3];
156 	int nbytes = enc_reg2nbytes(reg);
157 
158 	enc_set_bank(enc, reg);
159 	dout[0] = CMD_RCR(reg);
160 	spi_xfer(enc->slave, nbytes * 8, dout, din,
161 		SPI_XFER_BEGIN | SPI_XFER_END);
162 	return din[nbytes-1];
163 }
164 
165 /*
166  * Read a L/H register pair and return a word.
167  * Must be called with the L register's address.
168  */
169 static u16 enc_r16(enc_dev_t *enc, const u16 reg)
170 {
171 	u8 dout[3];
172 	u8 din[3];
173 	u16 result;
174 	int nbytes = enc_reg2nbytes(reg);
175 
176 	enc_set_bank(enc, reg);
177 	dout[0] = CMD_RCR(reg);
178 	spi_xfer(enc->slave, nbytes * 8, dout, din,
179 		SPI_XFER_BEGIN | SPI_XFER_END);
180 	result = din[nbytes-1];
181 	dout[0]++; /* next register */
182 	spi_xfer(enc->slave, nbytes * 8, dout, din,
183 		SPI_XFER_BEGIN | SPI_XFER_END);
184 	result |= din[nbytes-1] << 8;
185 	return result;
186 }
187 
188 /*
189  * Write a byte register
190  */
191 static void enc_w8(enc_dev_t *enc, const u16 reg, const u8 data)
192 {
193 	u8 dout[2];
194 
195 	enc_set_bank(enc, reg);
196 	dout[0] = CMD_WCR(reg);
197 	dout[1] = data;
198 	spi_xfer(enc->slave, 2 * 8, dout, NULL,
199 		SPI_XFER_BEGIN | SPI_XFER_END);
200 }
201 
202 /*
203  * Write a L/H register pair.
204  * Must be called with the L register's address.
205  */
206 static void enc_w16(enc_dev_t *enc, const u16 reg, const u16 data)
207 {
208 	u8 dout[2];
209 
210 	enc_set_bank(enc, reg);
211 	dout[0] = CMD_WCR(reg);
212 	dout[1] = data;
213 	spi_xfer(enc->slave, 2 * 8, dout, NULL,
214 		SPI_XFER_BEGIN | SPI_XFER_END);
215 	dout[0]++; /* next register */
216 	dout[1] = data >> 8;
217 	spi_xfer(enc->slave, 2 * 8, dout, NULL,
218 		SPI_XFER_BEGIN | SPI_XFER_END);
219 }
220 
221 /*
222  * Write a byte register, verify and retry
223  */
224 static void enc_w8_retry(enc_dev_t *enc, const u16 reg, const u8 data, const int c)
225 {
226 	u8 dout[2];
227 	u8 readback;
228 	int i;
229 
230 	enc_set_bank(enc, reg);
231 	for (i = 0; i < c; i++) {
232 		dout[0] = CMD_WCR(reg);
233 		dout[1] = data;
234 		spi_xfer(enc->slave, 2 * 8, dout, NULL,
235 			SPI_XFER_BEGIN | SPI_XFER_END);
236 		readback = enc_r8(enc, reg);
237 		if (readback == data)
238 			break;
239 		/* wait 1ms */
240 		udelay(1000);
241 	}
242 	if (i == c) {
243 		printf("%s: write reg 0x%03x failed\n", enc->dev->name, reg);
244 	}
245 }
246 
247 /*
248  * Read ENC RAM into buffer
249  */
250 static void enc_rbuf(enc_dev_t *enc, const u16 length, u8 *buf)
251 {
252 	u8 dout[1];
253 
254 	dout[0] = CMD_RBM;
255 	spi_xfer(enc->slave, 8, dout, NULL, SPI_XFER_BEGIN);
256 	spi_xfer(enc->slave, length * 8, NULL, buf, SPI_XFER_END);
257 #ifdef DEBUG
258 	puts("Rx:\n");
259 	print_buffer(0, buf, 1, length, 0);
260 #endif
261 }
262 
263 /*
264  * Write buffer into ENC RAM
265  */
266 static void enc_wbuf(enc_dev_t *enc, const u16 length, const u8 *buf, const u8 control)
267 {
268 	u8 dout[2];
269 	dout[0] = CMD_WBM;
270 	dout[1] = control;
271 	spi_xfer(enc->slave, 2 * 8, dout, NULL, SPI_XFER_BEGIN);
272 	spi_xfer(enc->slave, length * 8, buf, NULL, SPI_XFER_END);
273 #ifdef DEBUG
274 	puts("Tx:\n");
275 	print_buffer(0, buf, 1, length, 0);
276 #endif
277 }
278 
279 /*
280  * Try to claim the SPI bus.
281  * Print error message on failure.
282  */
283 static int enc_claim_bus(enc_dev_t *enc)
284 {
285 	int rc = spi_claim_bus(enc->slave);
286 	if (rc)
287 		printf("%s: failed to claim SPI bus\n", enc->dev->name);
288 	return rc;
289 }
290 
291 /*
292  * Release previously claimed SPI bus.
293  * This function is mainly for symmetry to enc_claim_bus().
294  * Let the toolchain decide to inline it...
295  */
296 static void enc_release_bus(enc_dev_t *enc)
297 {
298 	spi_release_bus(enc->slave);
299 }
300 
301 /*
302  * Read PHY register
303  */
304 static u16 enc_phy_read(enc_dev_t *enc, const u8 addr)
305 {
306 	uint64_t etime;
307 	u8 status;
308 
309 	enc_w8(enc, CTL_REG_MIREGADR, addr);
310 	enc_w8(enc, CTL_REG_MICMD, ENC_MICMD_MIIRD);
311 	/* 1 second timeout - only happens on hardware problem */
312 	etime = get_ticks() + get_tbclk();
313 	/* poll MISTAT.BUSY bit until operation is complete */
314 	do
315 	{
316 		status = enc_r8(enc, CTL_REG_MISTAT);
317 	} while (get_ticks() <= etime && (status & ENC_MISTAT_BUSY));
318 	if (status & ENC_MISTAT_BUSY) {
319 		printf("%s: timeout reading phy\n", enc->dev->name);
320 		return 0;
321 	}
322 	enc_w8(enc, CTL_REG_MICMD, 0);
323 	return enc_r16(enc, CTL_REG_MIRDL);
324 }
325 
326 /*
327  * Write PHY register
328  */
329 static void enc_phy_write(enc_dev_t *enc, const u8 addr, const u16 data)
330 {
331 	uint64_t etime;
332 	u8 status;
333 
334 	enc_w8(enc, CTL_REG_MIREGADR, addr);
335 	enc_w16(enc, CTL_REG_MIWRL, data);
336 	/* 1 second timeout - only happens on hardware problem */
337 	etime = get_ticks() + get_tbclk();
338 	/* poll MISTAT.BUSY bit until operation is complete */
339 	do
340 	{
341 		status = enc_r8(enc, CTL_REG_MISTAT);
342 	} while (get_ticks() <= etime && (status & ENC_MISTAT_BUSY));
343 	if (status & ENC_MISTAT_BUSY) {
344 		printf("%s: timeout writing phy\n", enc->dev->name);
345 		return;
346 	}
347 }
348 
349 /*
350  * Verify link status, wait if necessary
351  *
352  * Note: with a 10 MBit/s only PHY there is no autonegotiation possible,
353  * half/full duplex is a pure setup matter. For the time being, this driver
354  * will setup in half duplex mode only.
355  */
356 static int enc_phy_link_wait(enc_dev_t *enc)
357 {
358 	u16 status;
359 	int duplex;
360 	uint64_t etime;
361 
362 #ifdef CONFIG_ENC_SILENTLINK
363 	/* check if we have a link, then just return */
364 	status = enc_phy_read(enc, PHY_REG_PHSTAT1);
365 	if (status & ENC_PHSTAT1_LLSTAT)
366 		return 0;
367 #endif
368 
369 	/* wait for link with 1 second timeout */
370 	etime = get_ticks() + get_tbclk();
371 	while (get_ticks() <= etime) {
372 		status = enc_phy_read(enc, PHY_REG_PHSTAT1);
373 		if (status & ENC_PHSTAT1_LLSTAT) {
374 			/* now we have a link */
375 			status = enc_phy_read(enc, PHY_REG_PHSTAT2);
376 			duplex = (status & ENC_PHSTAT2_DPXSTAT) ? 1 : 0;
377 			printf("%s: link up, 10Mbps %s-duplex\n",
378 				enc->dev->name, duplex ? "full" : "half");
379 			return 0;
380 		}
381 		udelay(1000);
382 	}
383 
384 	/* timeout occured */
385 	printf("%s: link down\n", enc->dev->name);
386 	return 1;
387 }
388 
389 /*
390  * This function resets the receiver only.
391  */
392 static void enc_reset_rx(enc_dev_t *enc)
393 {
394 	u8 econ1;
395 
396 	econ1 = enc_r8(enc, CTL_REG_ECON1);
397 	if ((econ1 & ENC_ECON1_RXRST) == 0) {
398 		enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_RXRST);
399 		enc->rx_reset_counter = RX_RESET_COUNTER;
400 	}
401 }
402 
403 /*
404  * Reset receiver and reenable it.
405  */
406 static void enc_reset_rx_call(enc_dev_t *enc)
407 {
408 	enc_bclr(enc, CTL_REG_ECON1, ENC_ECON1_RXRST);
409 	enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_RXEN);
410 }
411 
412 /*
413  * Copy a packet from the receive ring and forward it to
414  * the protocol stack.
415  */
416 static void enc_receive(enc_dev_t *enc)
417 {
418 	u8 *packet = (u8 *)NetRxPackets[0];
419 	u16 pkt_len;
420 	u16 copy_len;
421 	u16 status;
422 	u8 pkt_cnt = 0;
423 	u16 rxbuf_rdpt;
424 	u8 hbuf[6];
425 
426 	enc_w16(enc, CTL_REG_ERDPTL, enc->next_pointer);
427 	do {
428 		enc_rbuf(enc, 6, hbuf);
429 		enc->next_pointer = hbuf[0] | (hbuf[1] << 8);
430 		pkt_len = hbuf[2] | (hbuf[3] << 8);
431 		status = hbuf[4] | (hbuf[5] << 8);
432 		debug("next_pointer=$%04x pkt_len=%u status=$%04x\n",
433 			enc->next_pointer, pkt_len, status);
434 		if (pkt_len <= ENC_MAX_FRM_LEN)
435 			copy_len = pkt_len;
436 		else
437 			copy_len = 0;
438 		if ((status & (1L << 7)) == 0) /* check Received Ok bit */
439 			copy_len = 0;
440 		/* check if next pointer is resonable */
441 		if (enc->next_pointer >= ENC_TX_BUF_START)
442 			copy_len = 0;
443 		if (copy_len > 0) {
444 			enc_rbuf(enc, copy_len, packet);
445 		}
446 		/* advance read pointer to next pointer */
447 		enc_w16(enc, CTL_REG_ERDPTL, enc->next_pointer);
448 		/* decrease packet counter */
449 		enc_bset(enc, CTL_REG_ECON2, ENC_ECON2_PKTDEC);
450 		/*
451 		 * Only odd values should be written to ERXRDPTL,
452 		 * see errata B4 pt.13
453 		 */
454 		rxbuf_rdpt = enc->next_pointer - 1;
455 		if ((rxbuf_rdpt < enc_r16(enc, CTL_REG_ERXSTL)) ||
456 			(rxbuf_rdpt > enc_r16(enc, CTL_REG_ERXNDL))) {
457 			enc_w16(enc, CTL_REG_ERXRDPTL,
458 				enc_r16(enc, CTL_REG_ERXNDL));
459 		} else {
460 			enc_w16(enc, CTL_REG_ERXRDPTL, rxbuf_rdpt);
461 		}
462 		/* read pktcnt */
463 		pkt_cnt = enc_r8(enc, CTL_REG_EPKTCNT);
464 		if (copy_len == 0) {
465 			(void)enc_r8(enc, CTL_REG_EIR);
466 			enc_reset_rx(enc);
467 			printf("%s: receive copy_len=0\n", enc->dev->name);
468 			continue;
469 		}
470 		/*
471 		 * Because NetReceive() might call enc_send(), we need to
472 		 * release the SPI bus, call NetReceive(), reclaim the bus
473 		 */
474 		enc_release_bus(enc);
475 		NetReceive(packet, pkt_len);
476 		if (enc_claim_bus(enc))
477 			return;
478 		(void)enc_r8(enc, CTL_REG_EIR);
479 	} while (pkt_cnt);
480 	/* Use EPKTCNT not EIR.PKTIF flag, see errata pt. 6 */
481 }
482 
483 /*
484  * Poll for completely received packets.
485  */
486 static void enc_poll(enc_dev_t *enc)
487 {
488 	u8 eir_reg;
489 	u8 pkt_cnt;
490 
491 #ifdef CONFIG_USE_IRQ
492 	/* clear global interrupt enable bit in enc28j60 */
493 	enc_bclr(enc, CTL_REG_EIE, ENC_EIE_INTIE);
494 #endif
495 	(void)enc_r8(enc, CTL_REG_ESTAT);
496 	eir_reg = enc_r8(enc, CTL_REG_EIR);
497 	if (eir_reg & ENC_EIR_TXIF) {
498 		/* clear TXIF bit in EIR */
499 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_TXIF);
500 	}
501 	/* We have to use pktcnt and not pktif bit, see errata pt. 6 */
502 	pkt_cnt = enc_r8(enc, CTL_REG_EPKTCNT);
503 	if (pkt_cnt > 0) {
504 		if ((eir_reg & ENC_EIR_PKTIF) == 0) {
505 			debug("enc_poll: pkt cnt > 0, but pktif not set\n");
506 		}
507 		enc_receive(enc);
508 		/*
509 		 * clear PKTIF bit in EIR, this should not need to be done
510 		 * but it seems like we get problems if we do not
511 		 */
512 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_PKTIF);
513 	}
514 	if (eir_reg & ENC_EIR_RXERIF) {
515 		printf("%s: rx error\n", enc->dev->name);
516 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_RXERIF);
517 	}
518 	if (eir_reg & ENC_EIR_TXERIF) {
519 		printf("%s: tx error\n", enc->dev->name);
520 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_TXERIF);
521 	}
522 #ifdef CONFIG_USE_IRQ
523 	/* set global interrupt enable bit in enc28j60 */
524 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_INTIE);
525 #endif
526 }
527 
528 /*
529  * Completely Reset the ENC
530  */
531 static void enc_reset(enc_dev_t *enc)
532 {
533 	u8 dout[1];
534 
535 	dout[0] = CMD_SRC;
536 	spi_xfer(enc->slave, 8, dout, NULL,
537 		SPI_XFER_BEGIN | SPI_XFER_END);
538 	/* sleep 1 ms. See errata pt. 2 */
539 	udelay(1000);
540 }
541 
542 /*
543  * Initialisation data for most of the ENC registers
544  */
545 static const u16 enc_initdata[] = {
546 	/*
547 	 * Setup the buffer space. The reset values are valid for the
548 	 * other pointers.
549 	 *
550 	 * We shall not write to ERXST, see errata pt. 5. Instead we
551 	 * have to make sure that ENC_RX_BUS_START is 0.
552 	 */
553 	CTL_REG_ERXSTL, ENC_RX_BUF_START,
554 	CTL_REG_ERXSTH, ENC_RX_BUF_START >> 8,
555 	CTL_REG_ERXNDL, ENC_RX_BUF_END,
556 	CTL_REG_ERXNDH, ENC_RX_BUF_END >> 8,
557 	CTL_REG_ERDPTL, ENC_RX_BUF_START,
558 	CTL_REG_ERDPTH, ENC_RX_BUF_START >> 8,
559 	/*
560 	 * Set the filter to receive only good-CRC, unicast and broadcast
561 	 * frames.
562 	 * Note: some DHCP servers return their answers as broadcasts!
563 	 * So its unwise to remove broadcast from this. This driver
564 	 * might incur receiver overruns with packet loss on a broadcast
565 	 * flooded network.
566 	 */
567 	CTL_REG_ERXFCON, ENC_RFR_BCEN | ENC_RFR_UCEN | ENC_RFR_CRCEN,
568 
569 	/* enable MAC to receive frames */
570 	CTL_REG_MACON1,
571 		ENC_MACON1_MARXEN | ENC_MACON1_TXPAUS | ENC_MACON1_RXPAUS,
572 
573 	/* configure pad, tx-crc and duplex */
574 	CTL_REG_MACON3,
575 		ENC_MACON3_PADCFG0 | ENC_MACON3_TXCRCEN |
576 		ENC_MACON3_FRMLNEN,
577 
578 	/* Allow infinite deferals if the medium is continously busy */
579 	CTL_REG_MACON4, ENC_MACON4_DEFER,
580 
581 	/* Late collisions occur beyond 63 bytes */
582 	CTL_REG_MACLCON2, 63,
583 
584 	/*
585 	 * Set (low byte) Non-Back-to_Back Inter-Packet Gap.
586 	 * Recommended 0x12
587 	 */
588 	CTL_REG_MAIPGL, 0x12,
589 
590 	/*
591 	 * Set (high byte) Non-Back-to_Back Inter-Packet Gap.
592 	 * Recommended 0x0c for half-duplex. Nothing for full-duplex
593 	 */
594 	CTL_REG_MAIPGH, 0x0C,
595 
596 	/* set maximum frame length */
597 	CTL_REG_MAMXFLL, ENC_MAX_FRM_LEN,
598 	CTL_REG_MAMXFLH, ENC_MAX_FRM_LEN >> 8,
599 
600 	/*
601 	 * Set MAC back-to-back inter-packet gap.
602 	 * Recommended 0x12 for half duplex
603 	 * and 0x15 for full duplex.
604 	 */
605 	CTL_REG_MABBIPG, 0x12,
606 
607 	/* end of table */
608 	0xffff
609 };
610 
611 /*
612  * Wait for the XTAL oscillator to become ready
613  */
614 static int enc_clock_wait(enc_dev_t *enc)
615 {
616 	uint64_t etime;
617 
618 	/* one second timeout */
619 	etime = get_ticks() + get_tbclk();
620 
621 	/*
622 	 * Wait for CLKRDY to become set (i.e., check that we can
623 	 * communicate with the ENC)
624 	 */
625 	do
626 	{
627 		if (enc_r8(enc, CTL_REG_ESTAT) & ENC_ESTAT_CLKRDY)
628 			return 0;
629 	} while (get_ticks() <= etime);
630 
631 	printf("%s: timeout waiting for CLKRDY\n", enc->dev->name);
632 	return -1;
633 }
634 
635 /*
636  * Write the MAC address into the ENC
637  */
638 static int enc_write_macaddr(enc_dev_t *enc)
639 {
640 	unsigned char *p = enc->dev->enetaddr;
641 
642 	enc_w8_retry(enc, CTL_REG_MAADR5, *p++, 5);
643 	enc_w8_retry(enc, CTL_REG_MAADR4, *p++, 5);
644 	enc_w8_retry(enc, CTL_REG_MAADR3, *p++, 5);
645 	enc_w8_retry(enc, CTL_REG_MAADR2, *p++, 5);
646 	enc_w8_retry(enc, CTL_REG_MAADR1, *p++, 5);
647 	enc_w8_retry(enc, CTL_REG_MAADR0, *p, 5);
648 	return 0;
649 }
650 
651 /*
652  * Setup most of the ENC registers
653  */
654 static int enc_setup(enc_dev_t *enc)
655 {
656 	u16 phid1 = 0;
657 	u16 phid2 = 0;
658 	const u16 *tp;
659 
660 	/* reset enc struct values */
661 	enc->next_pointer = ENC_RX_BUF_START;
662 	enc->rx_reset_counter = RX_RESET_COUNTER;
663 	enc->bank = 0xff;	/* invalidate current bank in enc28j60 */
664 
665 	/* verify PHY identification */
666 	phid1 = enc_phy_read(enc, PHY_REG_PHID1);
667 	phid2 = enc_phy_read(enc, PHY_REG_PHID2) & ENC_PHID2_MASK;
668 	if (phid1 != ENC_PHID1_VALUE || phid2 != ENC_PHID2_VALUE) {
669 		printf("%s: failed to identify PHY. Found %04x:%04x\n",
670 			enc->dev->name, phid1, phid2);
671 		return -1;
672 	}
673 
674 	/* now program registers */
675 	for (tp = enc_initdata; *tp != 0xffff; tp += 2)
676 		enc_w8_retry(enc, tp[0], tp[1], 10);
677 
678 	/*
679 	 * Prevent automatic loopback of data beeing transmitted by setting
680 	 * ENC_PHCON2_HDLDIS
681 	 */
682 	enc_phy_write(enc, PHY_REG_PHCON2, (1<<8));
683 
684 	/*
685 	 * LEDs configuration
686 	 * LEDA: LACFG = 0100 -> display link status
687 	 * LEDB: LBCFG = 0111 -> display TX & RX activity
688 	 * STRCH = 1 -> LED pulses
689 	 */
690 	enc_phy_write(enc, PHY_REG_PHLCON, 0x0472);
691 
692 	/* Reset PDPXMD-bit => half duplex */
693 	enc_phy_write(enc, PHY_REG_PHCON1, 0);
694 
695 #ifdef CONFIG_USE_IRQ
696 	/* enable interrupts */
697 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_PKTIE);
698 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_TXIE);
699 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_RXERIE);
700 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_TXERIE);
701 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_INTIE);
702 #endif
703 
704 	return 0;
705 }
706 
707 /*
708  * Check if ENC has been initialized.
709  * If not, try to initialize it.
710  * Remember initialized state in struct.
711  */
712 static int enc_initcheck(enc_dev_t *enc, const enum enc_initstate requiredstate)
713 {
714 	if (enc->initstate >= requiredstate)
715 		return 0;
716 
717 	if (enc->initstate < setupdone) {
718 		/* Initialize the ENC only */
719 		enc_reset(enc);
720 		/* if any of functions fails, skip the rest and return an error */
721 		if (enc_clock_wait(enc) || enc_setup(enc) || enc_write_macaddr(enc)) {
722 			return -1;
723 		}
724 		enc->initstate = setupdone;
725 	}
726 	/* if that's all we need, return here */
727 	if (enc->initstate >= requiredstate)
728 		return 0;
729 
730 	/* now wait for link ready condition */
731 	if (enc_phy_link_wait(enc)) {
732 		return -1;
733 	}
734 	enc->initstate = linkready;
735 	return 0;
736 }
737 
738 #if defined(CONFIG_CMD_MII)
739 /*
740  * Read a PHY register.
741  *
742  * This function is registered with miiphy_register().
743  */
744 int enc_miiphy_read(const char *devname, u8 phy_adr, u8 reg, u16 *value)
745 {
746 	struct eth_device *dev = eth_get_dev_by_name(devname);
747 	enc_dev_t *enc;
748 
749 	if (!dev || phy_adr != 0)
750 		return -1;
751 
752 	enc = dev->priv;
753 	if (enc_claim_bus(enc))
754 		return -1;
755 	if (enc_initcheck(enc, setupdone)) {
756 		enc_release_bus(enc);
757 		return -1;
758 	}
759 	*value = enc_phy_read(enc, reg);
760 	enc_release_bus(enc);
761 	return 0;
762 }
763 
764 /*
765  * Write a PHY register.
766  *
767  * This function is registered with miiphy_register().
768  */
769 int enc_miiphy_write(const char *devname, u8 phy_adr, u8 reg, u16 value)
770 {
771 	struct eth_device *dev = eth_get_dev_by_name(devname);
772 	enc_dev_t *enc;
773 
774 	if (!dev || phy_adr != 0)
775 		return -1;
776 
777 	enc = dev->priv;
778 	if (enc_claim_bus(enc))
779 		return -1;
780 	if (enc_initcheck(enc, setupdone)) {
781 		enc_release_bus(enc);
782 		return -1;
783 	}
784 	enc_phy_write(enc, reg, value);
785 	enc_release_bus(enc);
786 	return 0;
787 }
788 #endif
789 
790 /*
791  * Write hardware (MAC) address.
792  *
793  * This function entered into eth_device structure.
794  */
795 static int enc_write_hwaddr(struct eth_device *dev)
796 {
797 	enc_dev_t *enc = dev->priv;
798 
799 	if (enc_claim_bus(enc))
800 		return -1;
801 	if (enc_initcheck(enc, setupdone)) {
802 		enc_release_bus(enc);
803 		return -1;
804 	}
805 	enc_release_bus(enc);
806 	return 0;
807 }
808 
809 /*
810  * Initialize ENC28J60 for use.
811  *
812  * This function entered into eth_device structure.
813  */
814 static int enc_init(struct eth_device *dev, bd_t *bis)
815 {
816 	enc_dev_t *enc = dev->priv;
817 
818 	if (enc_claim_bus(enc))
819 		return -1;
820 	if (enc_initcheck(enc, linkready)) {
821 		enc_release_bus(enc);
822 		return -1;
823 	}
824 	/* enable receive */
825 	enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_RXEN);
826 	enc_release_bus(enc);
827 	return 0;
828 }
829 
830 /*
831  * Check for received packets.
832  *
833  * This function entered into eth_device structure.
834  */
835 static int enc_recv(struct eth_device *dev)
836 {
837 	enc_dev_t *enc = dev->priv;
838 
839 	if (enc_claim_bus(enc))
840 		return -1;
841 	if (enc_initcheck(enc, linkready)) {
842 		enc_release_bus(enc);
843 		return -1;
844 	}
845 	/* Check for dead receiver */
846 	if (enc->rx_reset_counter > 0)
847 		enc->rx_reset_counter--;
848 	else
849 		enc_reset_rx_call(enc);
850 	enc_poll(enc);
851 	enc_release_bus(enc);
852 	return 0;
853 }
854 
855 /*
856  * Send a packet.
857  *
858  * This function entered into eth_device structure.
859  *
860  * Should we wait here until we have a Link? Or shall we leave that to
861  * protocol retries?
862  */
863 static int enc_send(
864 	struct eth_device *dev,
865 	void *packet,
866 	int length)
867 {
868 	enc_dev_t *enc = dev->priv;
869 
870 	if (enc_claim_bus(enc))
871 		return -1;
872 	if (enc_initcheck(enc, linkready)) {
873 		enc_release_bus(enc);
874 		return -1;
875 	}
876 	/* setup transmit pointers */
877 	enc_w16(enc, CTL_REG_EWRPTL, ENC_TX_BUF_START);
878 	enc_w16(enc, CTL_REG_ETXNDL, length + ENC_TX_BUF_START);
879 	enc_w16(enc, CTL_REG_ETXSTL, ENC_TX_BUF_START);
880 	/* write packet to ENC */
881 	enc_wbuf(enc, length, (u8 *) packet, 0x00);
882 	/*
883 	 * Check that the internal transmit logic has not been altered
884 	 * by excessive collisions. Reset transmitter if so.
885 	 * See Errata B4 12 and 14.
886 	 */
887 	if (enc_r8(enc, CTL_REG_EIR) & ENC_EIR_TXERIF) {
888 		enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_TXRST);
889 		enc_bclr(enc, CTL_REG_ECON1, ENC_ECON1_TXRST);
890 	}
891 	enc_bclr(enc, CTL_REG_EIR, (ENC_EIR_TXERIF | ENC_EIR_TXIF));
892 	/* start transmitting */
893 	enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_TXRTS);
894 	enc_release_bus(enc);
895 	return 0;
896 }
897 
898 /*
899  * Finish use of ENC.
900  *
901  * This function entered into eth_device structure.
902  */
903 static void enc_halt(struct eth_device *dev)
904 {
905 	enc_dev_t *enc = dev->priv;
906 
907 	if (enc_claim_bus(enc))
908 		return;
909 	/* Just disable receiver */
910 	enc_bclr(enc, CTL_REG_ECON1, ENC_ECON1_RXEN);
911 	enc_release_bus(enc);
912 }
913 
914 /*
915  * This is the only exported function.
916  *
917  * It may be called several times with different bus:cs combinations.
918  */
919 int enc28j60_initialize(unsigned int bus, unsigned int cs,
920 	unsigned int max_hz, unsigned int mode)
921 {
922 	struct eth_device *dev;
923 	enc_dev_t *enc;
924 
925 	/* try to allocate, check and clear eth_device object */
926 	dev = malloc(sizeof(*dev));
927 	if (!dev) {
928 		return -1;
929 	}
930 	memset(dev, 0, sizeof(*dev));
931 
932 	/* try to allocate, check and clear enc_dev_t object */
933 	enc = malloc(sizeof(*enc));
934 	if (!enc) {
935 		free(dev);
936 		return -1;
937 	}
938 	memset(enc, 0, sizeof(*enc));
939 
940 	/* try to setup the SPI slave */
941 	enc->slave = spi_setup_slave(bus, cs, max_hz, mode);
942 	if (!enc->slave) {
943 		printf("enc28j60: invalid SPI device %i:%i\n", bus, cs);
944 		free(enc);
945 		free(dev);
946 		return -1;
947 	}
948 
949 	enc->dev = dev;
950 	/* now fill the eth_device object */
951 	dev->priv = enc;
952 	dev->init = enc_init;
953 	dev->halt = enc_halt;
954 	dev->send = enc_send;
955 	dev->recv = enc_recv;
956 	dev->write_hwaddr = enc_write_hwaddr;
957 	sprintf(dev->name, "enc%i.%i", bus, cs);
958 	eth_register(dev);
959 #if defined(CONFIG_CMD_MII)
960 	miiphy_register(dev->name, enc_miiphy_read, enc_miiphy_write);
961 #endif
962 	return 0;
963 }
964