xref: /rk3399_rockchip-uboot/drivers/net/enc28j60.c (revision 2a792753d6a1fe8f2310928ebd5534e4d87a8030)
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 net_process_received_packet() might call enc_send() in return, the bus
25  * must be released, net_process_received_packet() 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 occurred */
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 *)net_rx_packets[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 net_process_received_packet() might call enc_send(),
472 		 * we need to release the SPI bus, call
473 		 * net_process_received_packet(), reclaim the bus.
474 		 */
475 		enc_release_bus(enc);
476 		net_process_received_packet(packet, pkt_len);
477 		if (enc_claim_bus(enc))
478 			return;
479 		(void)enc_r8(enc, CTL_REG_EIR);
480 	} while (pkt_cnt);
481 	/* Use EPKTCNT not EIR.PKTIF flag, see errata pt. 6 */
482 }
483 
484 /*
485  * Poll for completely received packets.
486  */
487 static void enc_poll(enc_dev_t *enc)
488 {
489 	u8 eir_reg;
490 	u8 pkt_cnt;
491 
492 #ifdef CONFIG_USE_IRQ
493 	/* clear global interrupt enable bit in enc28j60 */
494 	enc_bclr(enc, CTL_REG_EIE, ENC_EIE_INTIE);
495 #endif
496 	(void)enc_r8(enc, CTL_REG_ESTAT);
497 	eir_reg = enc_r8(enc, CTL_REG_EIR);
498 	if (eir_reg & ENC_EIR_TXIF) {
499 		/* clear TXIF bit in EIR */
500 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_TXIF);
501 	}
502 	/* We have to use pktcnt and not pktif bit, see errata pt. 6 */
503 	pkt_cnt = enc_r8(enc, CTL_REG_EPKTCNT);
504 	if (pkt_cnt > 0) {
505 		if ((eir_reg & ENC_EIR_PKTIF) == 0) {
506 			debug("enc_poll: pkt cnt > 0, but pktif not set\n");
507 		}
508 		enc_receive(enc);
509 		/*
510 		 * clear PKTIF bit in EIR, this should not need to be done
511 		 * but it seems like we get problems if we do not
512 		 */
513 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_PKTIF);
514 	}
515 	if (eir_reg & ENC_EIR_RXERIF) {
516 		printf("%s: rx error\n", enc->dev->name);
517 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_RXERIF);
518 	}
519 	if (eir_reg & ENC_EIR_TXERIF) {
520 		printf("%s: tx error\n", enc->dev->name);
521 		enc_bclr(enc, CTL_REG_EIR, ENC_EIR_TXERIF);
522 	}
523 #ifdef CONFIG_USE_IRQ
524 	/* set global interrupt enable bit in enc28j60 */
525 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_INTIE);
526 #endif
527 }
528 
529 /*
530  * Completely Reset the ENC
531  */
532 static void enc_reset(enc_dev_t *enc)
533 {
534 	u8 dout[1];
535 
536 	dout[0] = CMD_SRC;
537 	spi_xfer(enc->slave, 8, dout, NULL,
538 		SPI_XFER_BEGIN | SPI_XFER_END);
539 	/* sleep 1 ms. See errata pt. 2 */
540 	udelay(1000);
541 }
542 
543 /*
544  * Initialisation data for most of the ENC registers
545  */
546 static const u16 enc_initdata[] = {
547 	/*
548 	 * Setup the buffer space. The reset values are valid for the
549 	 * other pointers.
550 	 *
551 	 * We shall not write to ERXST, see errata pt. 5. Instead we
552 	 * have to make sure that ENC_RX_BUS_START is 0.
553 	 */
554 	CTL_REG_ERXSTL, ENC_RX_BUF_START,
555 	CTL_REG_ERXSTH, ENC_RX_BUF_START >> 8,
556 	CTL_REG_ERXNDL, ENC_RX_BUF_END,
557 	CTL_REG_ERXNDH, ENC_RX_BUF_END >> 8,
558 	CTL_REG_ERDPTL, ENC_RX_BUF_START,
559 	CTL_REG_ERDPTH, ENC_RX_BUF_START >> 8,
560 	/*
561 	 * Set the filter to receive only good-CRC, unicast and broadcast
562 	 * frames.
563 	 * Note: some DHCP servers return their answers as broadcasts!
564 	 * So its unwise to remove broadcast from this. This driver
565 	 * might incur receiver overruns with packet loss on a broadcast
566 	 * flooded network.
567 	 */
568 	CTL_REG_ERXFCON, ENC_RFR_BCEN | ENC_RFR_UCEN | ENC_RFR_CRCEN,
569 
570 	/* enable MAC to receive frames */
571 	CTL_REG_MACON1,
572 		ENC_MACON1_MARXEN | ENC_MACON1_TXPAUS | ENC_MACON1_RXPAUS,
573 
574 	/* configure pad, tx-crc and duplex */
575 	CTL_REG_MACON3,
576 		ENC_MACON3_PADCFG0 | ENC_MACON3_TXCRCEN |
577 		ENC_MACON3_FRMLNEN,
578 
579 	/* Allow infinite deferals if the medium is continously busy */
580 	CTL_REG_MACON4, ENC_MACON4_DEFER,
581 
582 	/* Late collisions occur beyond 63 bytes */
583 	CTL_REG_MACLCON2, 63,
584 
585 	/*
586 	 * Set (low byte) Non-Back-to_Back Inter-Packet Gap.
587 	 * Recommended 0x12
588 	 */
589 	CTL_REG_MAIPGL, 0x12,
590 
591 	/*
592 	 * Set (high byte) Non-Back-to_Back Inter-Packet Gap.
593 	 * Recommended 0x0c for half-duplex. Nothing for full-duplex
594 	 */
595 	CTL_REG_MAIPGH, 0x0C,
596 
597 	/* set maximum frame length */
598 	CTL_REG_MAMXFLL, ENC_MAX_FRM_LEN,
599 	CTL_REG_MAMXFLH, ENC_MAX_FRM_LEN >> 8,
600 
601 	/*
602 	 * Set MAC back-to-back inter-packet gap.
603 	 * Recommended 0x12 for half duplex
604 	 * and 0x15 for full duplex.
605 	 */
606 	CTL_REG_MABBIPG, 0x12,
607 
608 	/* end of table */
609 	0xffff
610 };
611 
612 /*
613  * Wait for the XTAL oscillator to become ready
614  */
615 static int enc_clock_wait(enc_dev_t *enc)
616 {
617 	uint64_t etime;
618 
619 	/* one second timeout */
620 	etime = get_ticks() + get_tbclk();
621 
622 	/*
623 	 * Wait for CLKRDY to become set (i.e., check that we can
624 	 * communicate with the ENC)
625 	 */
626 	do
627 	{
628 		if (enc_r8(enc, CTL_REG_ESTAT) & ENC_ESTAT_CLKRDY)
629 			return 0;
630 	} while (get_ticks() <= etime);
631 
632 	printf("%s: timeout waiting for CLKRDY\n", enc->dev->name);
633 	return -1;
634 }
635 
636 /*
637  * Write the MAC address into the ENC
638  */
639 static int enc_write_macaddr(enc_dev_t *enc)
640 {
641 	unsigned char *p = enc->dev->enetaddr;
642 
643 	enc_w8_retry(enc, CTL_REG_MAADR5, *p++, 5);
644 	enc_w8_retry(enc, CTL_REG_MAADR4, *p++, 5);
645 	enc_w8_retry(enc, CTL_REG_MAADR3, *p++, 5);
646 	enc_w8_retry(enc, CTL_REG_MAADR2, *p++, 5);
647 	enc_w8_retry(enc, CTL_REG_MAADR1, *p++, 5);
648 	enc_w8_retry(enc, CTL_REG_MAADR0, *p, 5);
649 	return 0;
650 }
651 
652 /*
653  * Setup most of the ENC registers
654  */
655 static int enc_setup(enc_dev_t *enc)
656 {
657 	u16 phid1 = 0;
658 	u16 phid2 = 0;
659 	const u16 *tp;
660 
661 	/* reset enc struct values */
662 	enc->next_pointer = ENC_RX_BUF_START;
663 	enc->rx_reset_counter = RX_RESET_COUNTER;
664 	enc->bank = 0xff;	/* invalidate current bank in enc28j60 */
665 
666 	/* verify PHY identification */
667 	phid1 = enc_phy_read(enc, PHY_REG_PHID1);
668 	phid2 = enc_phy_read(enc, PHY_REG_PHID2) & ENC_PHID2_MASK;
669 	if (phid1 != ENC_PHID1_VALUE || phid2 != ENC_PHID2_VALUE) {
670 		printf("%s: failed to identify PHY. Found %04x:%04x\n",
671 			enc->dev->name, phid1, phid2);
672 		return -1;
673 	}
674 
675 	/* now program registers */
676 	for (tp = enc_initdata; *tp != 0xffff; tp += 2)
677 		enc_w8_retry(enc, tp[0], tp[1], 10);
678 
679 	/*
680 	 * Prevent automatic loopback of data beeing transmitted by setting
681 	 * ENC_PHCON2_HDLDIS
682 	 */
683 	enc_phy_write(enc, PHY_REG_PHCON2, (1<<8));
684 
685 	/*
686 	 * LEDs configuration
687 	 * LEDA: LACFG = 0100 -> display link status
688 	 * LEDB: LBCFG = 0111 -> display TX & RX activity
689 	 * STRCH = 1 -> LED pulses
690 	 */
691 	enc_phy_write(enc, PHY_REG_PHLCON, 0x0472);
692 
693 	/* Reset PDPXMD-bit => half duplex */
694 	enc_phy_write(enc, PHY_REG_PHCON1, 0);
695 
696 #ifdef CONFIG_USE_IRQ
697 	/* enable interrupts */
698 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_PKTIE);
699 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_TXIE);
700 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_RXERIE);
701 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_TXERIE);
702 	enc_bset(enc, CTL_REG_EIE, ENC_EIE_INTIE);
703 #endif
704 
705 	return 0;
706 }
707 
708 /*
709  * Check if ENC has been initialized.
710  * If not, try to initialize it.
711  * Remember initialized state in struct.
712  */
713 static int enc_initcheck(enc_dev_t *enc, const enum enc_initstate requiredstate)
714 {
715 	if (enc->initstate >= requiredstate)
716 		return 0;
717 
718 	if (enc->initstate < setupdone) {
719 		/* Initialize the ENC only */
720 		enc_reset(enc);
721 		/* if any of functions fails, skip the rest and return an error */
722 		if (enc_clock_wait(enc) || enc_setup(enc) || enc_write_macaddr(enc)) {
723 			return -1;
724 		}
725 		enc->initstate = setupdone;
726 	}
727 	/* if that's all we need, return here */
728 	if (enc->initstate >= requiredstate)
729 		return 0;
730 
731 	/* now wait for link ready condition */
732 	if (enc_phy_link_wait(enc)) {
733 		return -1;
734 	}
735 	enc->initstate = linkready;
736 	return 0;
737 }
738 
739 #if defined(CONFIG_CMD_MII)
740 /*
741  * Read a PHY register.
742  *
743  * This function is registered with miiphy_register().
744  */
745 int enc_miiphy_read(struct mii_dev *bus, int phy_adr, int devad, int reg)
746 {
747 	u16 value = 0;
748 	struct eth_device *dev = eth_get_dev_by_name(bus->name);
749 	enc_dev_t *enc;
750 
751 	if (!dev || phy_adr != 0)
752 		return -1;
753 
754 	enc = dev->priv;
755 	if (enc_claim_bus(enc))
756 		return -1;
757 	if (enc_initcheck(enc, setupdone)) {
758 		enc_release_bus(enc);
759 		return -1;
760 	}
761 	value = enc_phy_read(enc, reg);
762 	enc_release_bus(enc);
763 	return value;
764 }
765 
766 /*
767  * Write a PHY register.
768  *
769  * This function is registered with miiphy_register().
770  */
771 int enc_miiphy_write(struct mii_dev *bus, int phy_adr, int devad, int reg,
772 		     u16 value)
773 {
774 	struct eth_device *dev = eth_get_dev_by_name(bus->name);
775 	enc_dev_t *enc;
776 
777 	if (!dev || phy_adr != 0)
778 		return -1;
779 
780 	enc = dev->priv;
781 	if (enc_claim_bus(enc))
782 		return -1;
783 	if (enc_initcheck(enc, setupdone)) {
784 		enc_release_bus(enc);
785 		return -1;
786 	}
787 	enc_phy_write(enc, reg, value);
788 	enc_release_bus(enc);
789 	return 0;
790 }
791 #endif
792 
793 /*
794  * Write hardware (MAC) address.
795  *
796  * This function entered into eth_device structure.
797  */
798 static int enc_write_hwaddr(struct eth_device *dev)
799 {
800 	enc_dev_t *enc = dev->priv;
801 
802 	if (enc_claim_bus(enc))
803 		return -1;
804 	if (enc_initcheck(enc, setupdone)) {
805 		enc_release_bus(enc);
806 		return -1;
807 	}
808 	enc_release_bus(enc);
809 	return 0;
810 }
811 
812 /*
813  * Initialize ENC28J60 for use.
814  *
815  * This function entered into eth_device structure.
816  */
817 static int enc_init(struct eth_device *dev, bd_t *bis)
818 {
819 	enc_dev_t *enc = dev->priv;
820 
821 	if (enc_claim_bus(enc))
822 		return -1;
823 	if (enc_initcheck(enc, linkready)) {
824 		enc_release_bus(enc);
825 		return -1;
826 	}
827 	/* enable receive */
828 	enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_RXEN);
829 	enc_release_bus(enc);
830 	return 0;
831 }
832 
833 /*
834  * Check for received packets.
835  *
836  * This function entered into eth_device structure.
837  */
838 static int enc_recv(struct eth_device *dev)
839 {
840 	enc_dev_t *enc = dev->priv;
841 
842 	if (enc_claim_bus(enc))
843 		return -1;
844 	if (enc_initcheck(enc, linkready)) {
845 		enc_release_bus(enc);
846 		return -1;
847 	}
848 	/* Check for dead receiver */
849 	if (enc->rx_reset_counter > 0)
850 		enc->rx_reset_counter--;
851 	else
852 		enc_reset_rx_call(enc);
853 	enc_poll(enc);
854 	enc_release_bus(enc);
855 	return 0;
856 }
857 
858 /*
859  * Send a packet.
860  *
861  * This function entered into eth_device structure.
862  *
863  * Should we wait here until we have a Link? Or shall we leave that to
864  * protocol retries?
865  */
866 static int enc_send(
867 	struct eth_device *dev,
868 	void *packet,
869 	int length)
870 {
871 	enc_dev_t *enc = dev->priv;
872 
873 	if (enc_claim_bus(enc))
874 		return -1;
875 	if (enc_initcheck(enc, linkready)) {
876 		enc_release_bus(enc);
877 		return -1;
878 	}
879 	/* setup transmit pointers */
880 	enc_w16(enc, CTL_REG_EWRPTL, ENC_TX_BUF_START);
881 	enc_w16(enc, CTL_REG_ETXNDL, length + ENC_TX_BUF_START);
882 	enc_w16(enc, CTL_REG_ETXSTL, ENC_TX_BUF_START);
883 	/* write packet to ENC */
884 	enc_wbuf(enc, length, (u8 *) packet, 0x00);
885 	/*
886 	 * Check that the internal transmit logic has not been altered
887 	 * by excessive collisions. Reset transmitter if so.
888 	 * See Errata B4 12 and 14.
889 	 */
890 	if (enc_r8(enc, CTL_REG_EIR) & ENC_EIR_TXERIF) {
891 		enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_TXRST);
892 		enc_bclr(enc, CTL_REG_ECON1, ENC_ECON1_TXRST);
893 	}
894 	enc_bclr(enc, CTL_REG_EIR, (ENC_EIR_TXERIF | ENC_EIR_TXIF));
895 	/* start transmitting */
896 	enc_bset(enc, CTL_REG_ECON1, ENC_ECON1_TXRTS);
897 	enc_release_bus(enc);
898 	return 0;
899 }
900 
901 /*
902  * Finish use of ENC.
903  *
904  * This function entered into eth_device structure.
905  */
906 static void enc_halt(struct eth_device *dev)
907 {
908 	enc_dev_t *enc = dev->priv;
909 
910 	if (enc_claim_bus(enc))
911 		return;
912 	/* Just disable receiver */
913 	enc_bclr(enc, CTL_REG_ECON1, ENC_ECON1_RXEN);
914 	enc_release_bus(enc);
915 }
916 
917 /*
918  * This is the only exported function.
919  *
920  * It may be called several times with different bus:cs combinations.
921  */
922 int enc28j60_initialize(unsigned int bus, unsigned int cs,
923 	unsigned int max_hz, unsigned int mode)
924 {
925 	struct eth_device *dev;
926 	enc_dev_t *enc;
927 
928 	/* try to allocate, check and clear eth_device object */
929 	dev = malloc(sizeof(*dev));
930 	if (!dev) {
931 		return -1;
932 	}
933 	memset(dev, 0, sizeof(*dev));
934 
935 	/* try to allocate, check and clear enc_dev_t object */
936 	enc = malloc(sizeof(*enc));
937 	if (!enc) {
938 		free(dev);
939 		return -1;
940 	}
941 	memset(enc, 0, sizeof(*enc));
942 
943 	/* try to setup the SPI slave */
944 	enc->slave = spi_setup_slave(bus, cs, max_hz, mode);
945 	if (!enc->slave) {
946 		printf("enc28j60: invalid SPI device %i:%i\n", bus, cs);
947 		free(enc);
948 		free(dev);
949 		return -1;
950 	}
951 
952 	enc->dev = dev;
953 	/* now fill the eth_device object */
954 	dev->priv = enc;
955 	dev->init = enc_init;
956 	dev->halt = enc_halt;
957 	dev->send = enc_send;
958 	dev->recv = enc_recv;
959 	dev->write_hwaddr = enc_write_hwaddr;
960 	sprintf(dev->name, "enc%i.%i", bus, cs);
961 	eth_register(dev);
962 #if defined(CONFIG_CMD_MII)
963 	int retval;
964 	struct mii_dev *mdiodev = mdio_alloc();
965 	if (!mdiodev)
966 		return -ENOMEM;
967 	strncpy(mdiodev->name, dev->name, MDIO_NAME_LEN);
968 	mdiodev->read = enc_miiphy_read;
969 	mdiodev->write = enc_miiphy_write;
970 
971 	retval = mdio_register(mdiodev);
972 	if (retval < 0)
973 		return retval;
974 #endif
975 	return 0;
976 }
977