xref: /openbmc/u-boot/drivers/net/e1000_spi.c (revision bf494d7e)
1 #include <common.h>
2 #include <console.h>
3 #include "e1000.h"
4 #include <linux/compiler.h>
5 
6 /*-----------------------------------------------------------------------
7  * SPI transfer
8  *
9  * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
10  * "bitlen" bits in the SPI MISO port.  That's just the way SPI works.
11  *
12  * The source of the outgoing bits is the "dout" parameter and the
13  * destination of the input bits is the "din" parameter.  Note that "dout"
14  * and "din" can point to the same memory location, in which case the
15  * input data overwrites the output data (since both are buffered by
16  * temporary variables, this is OK).
17  *
18  * This may be interrupted with Ctrl-C if "intr" is true, otherwise it will
19  * never return an error.
20  */
21 static int e1000_spi_xfer(struct e1000_hw *hw, unsigned int bitlen,
22 		const void *dout_mem, void *din_mem, bool intr)
23 {
24 	const uint8_t *dout = dout_mem;
25 	uint8_t *din = din_mem;
26 
27 	uint8_t mask = 0;
28 	uint32_t eecd;
29 	unsigned long i;
30 
31 	/* Pre-read the control register */
32 	eecd = E1000_READ_REG(hw, EECD);
33 
34 	/* Iterate over each bit */
35 	for (i = 0, mask = 0x80; i < bitlen; i++, mask = (mask >> 1)?:0x80) {
36 		/* Check for interrupt */
37 		if (intr && ctrlc())
38 			return -1;
39 
40 		/* Determine the output bit */
41 		if (dout && dout[i >> 3] & mask)
42 			eecd |=  E1000_EECD_DI;
43 		else
44 			eecd &= ~E1000_EECD_DI;
45 
46 		/* Write the output bit and wait 50us */
47 		E1000_WRITE_REG(hw, EECD, eecd);
48 		E1000_WRITE_FLUSH(hw);
49 		udelay(50);
50 
51 		/* Poke the clock (waits 50us) */
52 		e1000_raise_ee_clk(hw, &eecd);
53 
54 		/* Now read the input bit */
55 		eecd = E1000_READ_REG(hw, EECD);
56 		if (din) {
57 			if (eecd & E1000_EECD_DO)
58 				din[i >> 3] |=  mask;
59 			else
60 				din[i >> 3] &= ~mask;
61 		}
62 
63 		/* Poke the clock again (waits 50us) */
64 		e1000_lower_ee_clk(hw, &eecd);
65 	}
66 
67 	/* Now clear any remaining bits of the input */
68 	if (din && (i & 7))
69 		din[i >> 3] &= ~((mask << 1) - 1);
70 
71 	return 0;
72 }
73 
74 #ifdef CONFIG_E1000_SPI_GENERIC
75 static inline struct e1000_hw *e1000_hw_from_spi(struct spi_slave *spi)
76 {
77 	return container_of(spi, struct e1000_hw, spi);
78 }
79 
80 /* Not sure why all of these are necessary */
81 void spi_init(void)   { /* Nothing to do */ }
82 
83 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
84 		unsigned int max_hz, unsigned int mode)
85 {
86 	/* Find the right PCI device */
87 	struct e1000_hw *hw = e1000_find_card(bus);
88 	if (!hw) {
89 		printf("ERROR: No such e1000 device: e1000#%u\n", bus);
90 		return NULL;
91 	}
92 
93 	/* Make sure it has an SPI chip */
94 	if (hw->eeprom.type != e1000_eeprom_spi) {
95 		E1000_ERR(hw, "No attached SPI EEPROM found!\n");
96 		return NULL;
97 	}
98 
99 	/* Argument sanity checks */
100 	if (cs != 0) {
101 		E1000_ERR(hw, "No such SPI chip: %u\n", cs);
102 		return NULL;
103 	}
104 	if (mode != SPI_MODE_0) {
105 		E1000_ERR(hw, "Only SPI MODE-0 is supported!\n");
106 		return NULL;
107 	}
108 
109 	/* TODO: Use max_hz somehow */
110 	E1000_DBG(hw->nic, "EEPROM SPI access requested\n");
111 	return &hw->spi;
112 }
113 
114 void spi_free_slave(struct spi_slave *spi)
115 {
116 	__maybe_unused struct e1000_hw *hw = e1000_hw_from_spi(spi);
117 	E1000_DBG(hw->nic, "EEPROM SPI access released\n");
118 }
119 
120 int spi_claim_bus(struct spi_slave *spi)
121 {
122 	struct e1000_hw *hw = e1000_hw_from_spi(spi);
123 
124 	if (e1000_acquire_eeprom(hw)) {
125 		E1000_ERR(hw, "EEPROM SPI cannot be acquired!\n");
126 		return -1;
127 	}
128 
129 	return 0;
130 }
131 
132 void spi_release_bus(struct spi_slave *spi)
133 {
134 	struct e1000_hw *hw = e1000_hw_from_spi(spi);
135 	e1000_release_eeprom(hw);
136 }
137 
138 /* Skinny wrapper around e1000_spi_xfer */
139 int spi_xfer(struct spi_slave *spi, unsigned int bitlen,
140 		const void *dout_mem, void *din_mem, unsigned long flags)
141 {
142 	struct e1000_hw *hw = e1000_hw_from_spi(spi);
143 	int ret;
144 
145 	if (flags & SPI_XFER_BEGIN)
146 		e1000_standby_eeprom(hw);
147 
148 	ret = e1000_spi_xfer(hw, bitlen, dout_mem, din_mem, true);
149 
150 	if (flags & SPI_XFER_END)
151 		e1000_standby_eeprom(hw);
152 
153 	return ret;
154 }
155 
156 #endif /* not CONFIG_E1000_SPI_GENERIC */
157 
158 #ifdef CONFIG_CMD_E1000
159 
160 /* The EEPROM opcodes */
161 #define SPI_EEPROM_ENABLE_WR	0x06
162 #define SPI_EEPROM_DISABLE_WR	0x04
163 #define SPI_EEPROM_WRITE_STATUS	0x01
164 #define SPI_EEPROM_READ_STATUS	0x05
165 #define SPI_EEPROM_WRITE_PAGE	0x02
166 #define SPI_EEPROM_READ_PAGE	0x03
167 
168 /* The EEPROM status bits */
169 #define SPI_EEPROM_STATUS_BUSY	0x01
170 #define SPI_EEPROM_STATUS_WREN	0x02
171 
172 static int e1000_spi_eeprom_enable_wr(struct e1000_hw *hw, bool intr)
173 {
174 	u8 op[] = { SPI_EEPROM_ENABLE_WR };
175 	e1000_standby_eeprom(hw);
176 	return e1000_spi_xfer(hw, 8*sizeof(op), op, NULL, intr);
177 }
178 
179 /*
180  * These have been tested to perform correctly, but they are not used by any
181  * of the EEPROM commands at this time.
182  */
183 static __maybe_unused int e1000_spi_eeprom_disable_wr(struct e1000_hw *hw,
184 						      bool intr)
185 {
186 	u8 op[] = { SPI_EEPROM_DISABLE_WR };
187 	e1000_standby_eeprom(hw);
188 	return e1000_spi_xfer(hw, 8*sizeof(op), op, NULL, intr);
189 }
190 
191 static __maybe_unused int e1000_spi_eeprom_write_status(struct e1000_hw *hw,
192 							u8 status, bool intr)
193 {
194 	u8 op[] = { SPI_EEPROM_WRITE_STATUS, status };
195 	e1000_standby_eeprom(hw);
196 	return e1000_spi_xfer(hw, 8*sizeof(op), op, NULL, intr);
197 }
198 
199 static int e1000_spi_eeprom_read_status(struct e1000_hw *hw, bool intr)
200 {
201 	u8 op[] = { SPI_EEPROM_READ_STATUS, 0 };
202 	e1000_standby_eeprom(hw);
203 	if (e1000_spi_xfer(hw, 8*sizeof(op), op, op, intr))
204 		return -1;
205 	return op[1];
206 }
207 
208 static int e1000_spi_eeprom_write_page(struct e1000_hw *hw,
209 		const void *data, u16 off, u16 len, bool intr)
210 {
211 	u8 op[] = {
212 		SPI_EEPROM_WRITE_PAGE,
213 		(off >> (hw->eeprom.address_bits - 8)) & 0xff, off & 0xff
214 	};
215 
216 	e1000_standby_eeprom(hw);
217 
218 	if (e1000_spi_xfer(hw, 8 + hw->eeprom.address_bits, op, NULL, intr))
219 		return -1;
220 	if (e1000_spi_xfer(hw, len << 3, data, NULL, intr))
221 		return -1;
222 
223 	return 0;
224 }
225 
226 static int e1000_spi_eeprom_read_page(struct e1000_hw *hw,
227 		void *data, u16 off, u16 len, bool intr)
228 {
229 	u8 op[] = {
230 		SPI_EEPROM_READ_PAGE,
231 		(off >> (hw->eeprom.address_bits - 8)) & 0xff, off & 0xff
232 	};
233 
234 	e1000_standby_eeprom(hw);
235 
236 	if (e1000_spi_xfer(hw, 8 + hw->eeprom.address_bits, op, NULL, intr))
237 		return -1;
238 	if (e1000_spi_xfer(hw, len << 3, NULL, data, intr))
239 		return -1;
240 
241 	return 0;
242 }
243 
244 static int e1000_spi_eeprom_poll_ready(struct e1000_hw *hw, bool intr)
245 {
246 	int status;
247 	while ((status = e1000_spi_eeprom_read_status(hw, intr)) >= 0) {
248 		if (!(status & SPI_EEPROM_STATUS_BUSY))
249 			return 0;
250 	}
251 	return -1;
252 }
253 
254 static int e1000_spi_eeprom_dump(struct e1000_hw *hw,
255 		void *data, u16 off, unsigned int len, bool intr)
256 {
257 	/* Interruptibly wait for the EEPROM to be ready */
258 	if (e1000_spi_eeprom_poll_ready(hw, intr))
259 		return -1;
260 
261 	/* Dump each page in sequence */
262 	while (len) {
263 		/* Calculate the data bytes on this page */
264 		u16 pg_off = off & (hw->eeprom.page_size - 1);
265 		u16 pg_len = hw->eeprom.page_size - pg_off;
266 		if (pg_len > len)
267 			pg_len = len;
268 
269 		/* Now dump the page */
270 		if (e1000_spi_eeprom_read_page(hw, data, off, pg_len, intr))
271 			return -1;
272 
273 		/* Otherwise go on to the next page */
274 		len  -= pg_len;
275 		off  += pg_len;
276 		data += pg_len;
277 	}
278 
279 	/* We're done! */
280 	return 0;
281 }
282 
283 static int e1000_spi_eeprom_program(struct e1000_hw *hw,
284 		const void *data, u16 off, u16 len, bool intr)
285 {
286 	/* Program each page in sequence */
287 	while (len) {
288 		/* Calculate the data bytes on this page */
289 		u16 pg_off = off & (hw->eeprom.page_size - 1);
290 		u16 pg_len = hw->eeprom.page_size - pg_off;
291 		if (pg_len > len)
292 			pg_len = len;
293 
294 		/* Interruptibly wait for the EEPROM to be ready */
295 		if (e1000_spi_eeprom_poll_ready(hw, intr))
296 			return -1;
297 
298 		/* Enable write access */
299 		if (e1000_spi_eeprom_enable_wr(hw, intr))
300 			return -1;
301 
302 		/* Now program the page */
303 		if (e1000_spi_eeprom_write_page(hw, data, off, pg_len, intr))
304 			return -1;
305 
306 		/* Otherwise go on to the next page */
307 		len  -= pg_len;
308 		off  += pg_len;
309 		data += pg_len;
310 	}
311 
312 	/* Wait for the last write to complete */
313 	if (e1000_spi_eeprom_poll_ready(hw, intr))
314 		return -1;
315 
316 	/* We're done! */
317 	return 0;
318 }
319 
320 static int do_e1000_spi_show(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
321 		int argc, char * const argv[])
322 {
323 	unsigned int length = 0;
324 	u16 i, offset = 0;
325 	u8 *buffer;
326 	int err;
327 
328 	if (argc > 2) {
329 		cmd_usage(cmdtp);
330 		return 1;
331 	}
332 
333 	/* Parse the offset and length */
334 	if (argc >= 1)
335 		offset = simple_strtoul(argv[0], NULL, 0);
336 	if (argc == 2)
337 		length = simple_strtoul(argv[1], NULL, 0);
338 	else if (offset < (hw->eeprom.word_size << 1))
339 		length = (hw->eeprom.word_size << 1) - offset;
340 
341 	/* Extra sanity checks */
342 	if (!length) {
343 		E1000_ERR(hw, "Requested zero-sized dump!\n");
344 		return 1;
345 	}
346 	if ((0x10000 < length) || (0x10000 - length < offset)) {
347 		E1000_ERR(hw, "Can't dump past 0xFFFF!\n");
348 		return 1;
349 	}
350 
351 	/* Allocate a buffer to hold stuff */
352 	buffer = malloc(length);
353 	if (!buffer) {
354 		E1000_ERR(hw, "Out of Memory!\n");
355 		return 1;
356 	}
357 
358 	/* Acquire the EEPROM and perform the dump */
359 	if (e1000_acquire_eeprom(hw)) {
360 		E1000_ERR(hw, "EEPROM SPI cannot be acquired!\n");
361 		free(buffer);
362 		return 1;
363 	}
364 	err = e1000_spi_eeprom_dump(hw, buffer, offset, length, true);
365 	e1000_release_eeprom(hw);
366 	if (err) {
367 		E1000_ERR(hw, "Interrupted!\n");
368 		free(buffer);
369 		return 1;
370 	}
371 
372 	/* Now hexdump the result */
373 	printf("%s: ===== Intel e1000 EEPROM (0x%04hX - 0x%04hX) =====",
374 			hw->name, offset, offset + length - 1);
375 	for (i = 0; i < length; i++) {
376 		if ((i & 0xF) == 0)
377 			printf("\n%s: %04hX: ", hw->name, offset + i);
378 		else if ((i & 0xF) == 0x8)
379 			printf(" ");
380 		printf(" %02hx", buffer[i]);
381 	}
382 	printf("\n");
383 
384 	/* Success! */
385 	free(buffer);
386 	return 0;
387 }
388 
389 static int do_e1000_spi_dump(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
390 		int argc, char * const argv[])
391 {
392 	unsigned int length;
393 	u16 offset;
394 	void *dest;
395 
396 	if (argc != 3) {
397 		cmd_usage(cmdtp);
398 		return 1;
399 	}
400 
401 	/* Parse the arguments */
402 	dest = (void *)simple_strtoul(argv[0], NULL, 16);
403 	offset = simple_strtoul(argv[1], NULL, 0);
404 	length = simple_strtoul(argv[2], NULL, 0);
405 
406 	/* Extra sanity checks */
407 	if (!length) {
408 		E1000_ERR(hw, "Requested zero-sized dump!\n");
409 		return 1;
410 	}
411 	if ((0x10000 < length) || (0x10000 - length < offset)) {
412 		E1000_ERR(hw, "Can't dump past 0xFFFF!\n");
413 		return 1;
414 	}
415 
416 	/* Acquire the EEPROM */
417 	if (e1000_acquire_eeprom(hw)) {
418 		E1000_ERR(hw, "EEPROM SPI cannot be acquired!\n");
419 		return 1;
420 	}
421 
422 	/* Perform the programming operation */
423 	if (e1000_spi_eeprom_dump(hw, dest, offset, length, true) < 0) {
424 		E1000_ERR(hw, "Interrupted!\n");
425 		e1000_release_eeprom(hw);
426 		return 1;
427 	}
428 
429 	e1000_release_eeprom(hw);
430 	printf("%s: ===== EEPROM DUMP COMPLETE =====\n", hw->name);
431 	return 0;
432 }
433 
434 static int do_e1000_spi_program(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
435 		int argc, char * const argv[])
436 {
437 	unsigned int length;
438 	const void *source;
439 	u16 offset;
440 
441 	if (argc != 3) {
442 		cmd_usage(cmdtp);
443 		return 1;
444 	}
445 
446 	/* Parse the arguments */
447 	source = (const void *)simple_strtoul(argv[0], NULL, 16);
448 	offset = simple_strtoul(argv[1], NULL, 0);
449 	length = simple_strtoul(argv[2], NULL, 0);
450 
451 	/* Acquire the EEPROM */
452 	if (e1000_acquire_eeprom(hw)) {
453 		E1000_ERR(hw, "EEPROM SPI cannot be acquired!\n");
454 		return 1;
455 	}
456 
457 	/* Perform the programming operation */
458 	if (e1000_spi_eeprom_program(hw, source, offset, length, true) < 0) {
459 		E1000_ERR(hw, "Interrupted!\n");
460 		e1000_release_eeprom(hw);
461 		return 1;
462 	}
463 
464 	e1000_release_eeprom(hw);
465 	printf("%s: ===== EEPROM PROGRAMMED =====\n", hw->name);
466 	return 0;
467 }
468 
469 static int do_e1000_spi_checksum(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
470 		int argc, char * const argv[])
471 {
472 	uint16_t i, length, checksum = 0, checksum_reg;
473 	uint16_t *buffer;
474 	bool upd;
475 
476 	if (argc == 0)
477 		upd = 0;
478 	else if ((argc == 1) && !strcmp(argv[0], "update"))
479 		upd = 1;
480 	else {
481 		cmd_usage(cmdtp);
482 		return 1;
483 	}
484 
485 	/* Allocate a temporary buffer */
486 	length = sizeof(uint16_t) * (EEPROM_CHECKSUM_REG + 1);
487 	buffer = malloc(length);
488 	if (!buffer) {
489 		E1000_ERR(hw, "Unable to allocate EEPROM buffer!\n");
490 		return 1;
491 	}
492 
493 	/* Acquire the EEPROM */
494 	if (e1000_acquire_eeprom(hw)) {
495 		E1000_ERR(hw, "EEPROM SPI cannot be acquired!\n");
496 		return 1;
497 	}
498 
499 	/* Read the EEPROM */
500 	if (e1000_spi_eeprom_dump(hw, buffer, 0, length, true) < 0) {
501 		E1000_ERR(hw, "Interrupted!\n");
502 		e1000_release_eeprom(hw);
503 		return 1;
504 	}
505 
506 	/* Compute the checksum and read the expected value */
507 	for (i = 0; i < EEPROM_CHECKSUM_REG; i++)
508 		checksum += le16_to_cpu(buffer[i]);
509 	checksum = ((uint16_t)EEPROM_SUM) - checksum;
510 	checksum_reg = le16_to_cpu(buffer[i]);
511 
512 	/* Verify it! */
513 	if (checksum_reg == checksum) {
514 		printf("%s: INFO: EEPROM checksum is correct! (0x%04hx)\n",
515 				hw->name, checksum);
516 		e1000_release_eeprom(hw);
517 		return 0;
518 	}
519 
520 	/* Hrm, verification failed, print an error */
521 	E1000_ERR(hw, "EEPROM checksum is incorrect!\n");
522 	E1000_ERR(hw, "  ...register was 0x%04hx, calculated 0x%04hx\n",
523 		  checksum_reg, checksum);
524 
525 	/* If they didn't ask us to update it, just return an error */
526 	if (!upd) {
527 		e1000_release_eeprom(hw);
528 		return 1;
529 	}
530 
531 	/* Ok, correct it! */
532 	printf("%s: Reprogramming the EEPROM checksum...\n", hw->name);
533 	buffer[i] = cpu_to_le16(checksum);
534 	if (e1000_spi_eeprom_program(hw, &buffer[i], i * sizeof(uint16_t),
535 			sizeof(uint16_t), true)) {
536 		E1000_ERR(hw, "Interrupted!\n");
537 		e1000_release_eeprom(hw);
538 		return 1;
539 	}
540 
541 	e1000_release_eeprom(hw);
542 	return 0;
543 }
544 
545 int do_e1000_spi(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
546 		int argc, char * const argv[])
547 {
548 	if (argc < 1) {
549 		cmd_usage(cmdtp);
550 		return 1;
551 	}
552 
553 	/* Make sure it has an SPI chip */
554 	if (hw->eeprom.type != e1000_eeprom_spi) {
555 		E1000_ERR(hw, "No attached SPI EEPROM found (%d)!\n",
556 			  hw->eeprom.type);
557 		return 1;
558 	}
559 
560 	/* Check the eeprom sub-sub-command arguments */
561 	if (!strcmp(argv[0], "show"))
562 		return do_e1000_spi_show(cmdtp, hw, argc - 1, argv + 1);
563 
564 	if (!strcmp(argv[0], "dump"))
565 		return do_e1000_spi_dump(cmdtp, hw, argc - 1, argv + 1);
566 
567 	if (!strcmp(argv[0], "program"))
568 		return do_e1000_spi_program(cmdtp, hw, argc - 1, argv + 1);
569 
570 	if (!strcmp(argv[0], "checksum"))
571 		return do_e1000_spi_checksum(cmdtp, hw, argc - 1, argv + 1);
572 
573 	cmd_usage(cmdtp);
574 	return 1;
575 }
576 
577 #endif /* not CONFIG_CMD_E1000 */
578