xref: /openbmc/u-boot/drivers/net/e1000_spi.c (revision bfcc40bb)
1 #include "e1000.h"
2 #include <linux/compiler.h>
3 
4 /*-----------------------------------------------------------------------
5  * SPI transfer
6  *
7  * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
8  * "bitlen" bits in the SPI MISO port.  That's just the way SPI works.
9  *
10  * The source of the outgoing bits is the "dout" parameter and the
11  * destination of the input bits is the "din" parameter.  Note that "dout"
12  * and "din" can point to the same memory location, in which case the
13  * input data overwrites the output data (since both are buffered by
14  * temporary variables, this is OK).
15  *
16  * This may be interrupted with Ctrl-C if "intr" is true, otherwise it will
17  * never return an error.
18  */
19 static int e1000_spi_xfer(struct e1000_hw *hw, unsigned int bitlen,
20 		const void *dout_mem, void *din_mem, boolean_t intr)
21 {
22 	const uint8_t *dout = dout_mem;
23 	uint8_t *din = din_mem;
24 
25 	uint8_t mask = 0;
26 	uint32_t eecd;
27 	unsigned long i;
28 
29 	/* Pre-read the control register */
30 	eecd = E1000_READ_REG(hw, EECD);
31 
32 	/* Iterate over each bit */
33 	for (i = 0, mask = 0x80; i < bitlen; i++, mask = (mask >> 1)?:0x80) {
34 		/* Check for interrupt */
35 		if (intr && ctrlc())
36 			return -1;
37 
38 		/* Determine the output bit */
39 		if (dout && dout[i >> 3] & mask)
40 			eecd |=  E1000_EECD_DI;
41 		else
42 			eecd &= ~E1000_EECD_DI;
43 
44 		/* Write the output bit and wait 50us */
45 		E1000_WRITE_REG(hw, EECD, eecd);
46 		E1000_WRITE_FLUSH(hw);
47 		udelay(50);
48 
49 		/* Poke the clock (waits 50us) */
50 		e1000_raise_ee_clk(hw, &eecd);
51 
52 		/* Now read the input bit */
53 		eecd = E1000_READ_REG(hw, EECD);
54 		if (din) {
55 			if (eecd & E1000_EECD_DO)
56 				din[i >> 3] |=  mask;
57 			else
58 				din[i >> 3] &= ~mask;
59 		}
60 
61 		/* Poke the clock again (waits 50us) */
62 		e1000_lower_ee_clk(hw, &eecd);
63 	}
64 
65 	/* Now clear any remaining bits of the input */
66 	if (din && (i & 7))
67 		din[i >> 3] &= ~((mask << 1) - 1);
68 
69 	return 0;
70 }
71 
72 #ifdef CONFIG_E1000_SPI_GENERIC
73 static inline struct e1000_hw *e1000_hw_from_spi(struct spi_slave *spi)
74 {
75 	return container_of(spi, struct e1000_hw, spi);
76 }
77 
78 /* Not sure why all of these are necessary */
79 void spi_init_r(void) { /* Nothing to do */ }
80 void spi_init_f(void) { /* Nothing to do */ }
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->nic, "No attached SPI EEPROM found!\n");
96 		return NULL;
97 	}
98 
99 	/* Argument sanity checks */
100 	if (cs != 0) {
101 		E1000_ERR(hw->nic, "No such SPI chip: %u\n", cs);
102 		return NULL;
103 	}
104 	if (mode != SPI_MODE_0) {
105 		E1000_ERR(hw->nic, "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->nic, "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, boolean_t 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 #if 0
184 static int e1000_spi_eeprom_disable_wr(struct e1000_hw *hw, boolean_t 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 int e1000_spi_eeprom_write_status(struct e1000_hw *hw,
192 		u8 status, boolean_t 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 #endif
199 
200 static int e1000_spi_eeprom_read_status(struct e1000_hw *hw, boolean_t intr)
201 {
202 	u8 op[] = { SPI_EEPROM_READ_STATUS, 0 };
203 	e1000_standby_eeprom(hw);
204 	if (e1000_spi_xfer(hw, 8*sizeof(op), op, op, intr))
205 		return -1;
206 	return op[1];
207 }
208 
209 static int e1000_spi_eeprom_write_page(struct e1000_hw *hw,
210 		const void *data, u16 off, u16 len, boolean_t intr)
211 {
212 	u8 op[] = {
213 		SPI_EEPROM_WRITE_PAGE,
214 		(off >> (hw->eeprom.address_bits - 8)) & 0xff, off & 0xff
215 	};
216 
217 	e1000_standby_eeprom(hw);
218 
219 	if (e1000_spi_xfer(hw, 8 + hw->eeprom.address_bits, op, NULL, intr))
220 		return -1;
221 	if (e1000_spi_xfer(hw, len << 3, data, NULL, intr))
222 		return -1;
223 
224 	return 0;
225 }
226 
227 static int e1000_spi_eeprom_read_page(struct e1000_hw *hw,
228 		void *data, u16 off, u16 len, boolean_t intr)
229 {
230 	u8 op[] = {
231 		SPI_EEPROM_READ_PAGE,
232 		(off >> (hw->eeprom.address_bits - 8)) & 0xff, off & 0xff
233 	};
234 
235 	e1000_standby_eeprom(hw);
236 
237 	if (e1000_spi_xfer(hw, 8 + hw->eeprom.address_bits, op, NULL, intr))
238 		return -1;
239 	if (e1000_spi_xfer(hw, len << 3, NULL, data, intr))
240 		return -1;
241 
242 	return 0;
243 }
244 
245 static int e1000_spi_eeprom_poll_ready(struct e1000_hw *hw, boolean_t intr)
246 {
247 	int status;
248 	while ((status = e1000_spi_eeprom_read_status(hw, intr)) >= 0) {
249 		if (!(status & SPI_EEPROM_STATUS_BUSY))
250 			return 0;
251 	}
252 	return -1;
253 }
254 
255 static int e1000_spi_eeprom_dump(struct e1000_hw *hw,
256 		void *data, u16 off, unsigned int len, boolean_t intr)
257 {
258 	/* Interruptibly wait for the EEPROM to be ready */
259 	if (e1000_spi_eeprom_poll_ready(hw, intr))
260 		return -1;
261 
262 	/* Dump each page in sequence */
263 	while (len) {
264 		/* Calculate the data bytes on this page */
265 		u16 pg_off = off & (hw->eeprom.page_size - 1);
266 		u16 pg_len = hw->eeprom.page_size - pg_off;
267 		if (pg_len > len)
268 			pg_len = len;
269 
270 		/* Now dump the page */
271 		if (e1000_spi_eeprom_read_page(hw, data, off, pg_len, intr))
272 			return -1;
273 
274 		/* Otherwise go on to the next page */
275 		len  -= pg_len;
276 		off  += pg_len;
277 		data += pg_len;
278 	}
279 
280 	/* We're done! */
281 	return 0;
282 }
283 
284 static int e1000_spi_eeprom_program(struct e1000_hw *hw,
285 		const void *data, u16 off, u16 len, boolean_t intr)
286 {
287 	/* Program each page in sequence */
288 	while (len) {
289 		/* Calculate the data bytes on this page */
290 		u16 pg_off = off & (hw->eeprom.page_size - 1);
291 		u16 pg_len = hw->eeprom.page_size - pg_off;
292 		if (pg_len > len)
293 			pg_len = len;
294 
295 		/* Interruptibly wait for the EEPROM to be ready */
296 		if (e1000_spi_eeprom_poll_ready(hw, intr))
297 			return -1;
298 
299 		/* Enable write access */
300 		if (e1000_spi_eeprom_enable_wr(hw, intr))
301 			return -1;
302 
303 		/* Now program the page */
304 		if (e1000_spi_eeprom_write_page(hw, data, off, pg_len, intr))
305 			return -1;
306 
307 		/* Otherwise go on to the next page */
308 		len  -= pg_len;
309 		off  += pg_len;
310 		data += pg_len;
311 	}
312 
313 	/* Wait for the last write to complete */
314 	if (e1000_spi_eeprom_poll_ready(hw, intr))
315 		return -1;
316 
317 	/* We're done! */
318 	return 0;
319 }
320 
321 static int do_e1000_spi_show(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
322 		int argc, char * const argv[])
323 {
324 	unsigned int length = 0;
325 	u16 i, offset = 0;
326 	u8 *buffer;
327 	int err;
328 
329 	if (argc > 2) {
330 		cmd_usage(cmdtp);
331 		return 1;
332 	}
333 
334 	/* Parse the offset and length */
335 	if (argc >= 1)
336 		offset = simple_strtoul(argv[0], NULL, 0);
337 	if (argc == 2)
338 		length = simple_strtoul(argv[1], NULL, 0);
339 	else if (offset < (hw->eeprom.word_size << 1))
340 		length = (hw->eeprom.word_size << 1) - offset;
341 
342 	/* Extra sanity checks */
343 	if (!length) {
344 		E1000_ERR(hw->nic, "Requested zero-sized dump!\n");
345 		return 1;
346 	}
347 	if ((0x10000 < length) || (0x10000 - length < offset)) {
348 		E1000_ERR(hw->nic, "Can't dump past 0xFFFF!\n");
349 		return 1;
350 	}
351 
352 	/* Allocate a buffer to hold stuff */
353 	buffer = malloc(length);
354 	if (!buffer) {
355 		E1000_ERR(hw->nic, "Out of Memory!\n");
356 		return 1;
357 	}
358 
359 	/* Acquire the EEPROM and perform the dump */
360 	if (e1000_acquire_eeprom(hw)) {
361 		E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
362 		free(buffer);
363 		return 1;
364 	}
365 	err = e1000_spi_eeprom_dump(hw, buffer, offset, length, TRUE);
366 	e1000_release_eeprom(hw);
367 	if (err) {
368 		E1000_ERR(hw->nic, "Interrupted!\n");
369 		free(buffer);
370 		return 1;
371 	}
372 
373 	/* Now hexdump the result */
374 	printf("%s: ===== Intel e1000 EEPROM (0x%04hX - 0x%04hX) =====",
375 			hw->nic->name, offset, offset + length - 1);
376 	for (i = 0; i < length; i++) {
377 		if ((i & 0xF) == 0)
378 			printf("\n%s: %04hX: ", hw->nic->name, offset + i);
379 		else if ((i & 0xF) == 0x8)
380 			printf(" ");
381 		printf(" %02hx", buffer[i]);
382 	}
383 	printf("\n");
384 
385 	/* Success! */
386 	free(buffer);
387 	return 0;
388 }
389 
390 static int do_e1000_spi_dump(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
391 		int argc, char * const argv[])
392 {
393 	unsigned int length;
394 	u16 offset;
395 	void *dest;
396 
397 	if (argc != 3) {
398 		cmd_usage(cmdtp);
399 		return 1;
400 	}
401 
402 	/* Parse the arguments */
403 	dest = (void *)simple_strtoul(argv[0], NULL, 16);
404 	offset = simple_strtoul(argv[1], NULL, 0);
405 	length = simple_strtoul(argv[2], NULL, 0);
406 
407 	/* Extra sanity checks */
408 	if (!length) {
409 		E1000_ERR(hw->nic, "Requested zero-sized dump!\n");
410 		return 1;
411 	}
412 	if ((0x10000 < length) || (0x10000 - length < offset)) {
413 		E1000_ERR(hw->nic, "Can't dump past 0xFFFF!\n");
414 		return 1;
415 	}
416 
417 	/* Acquire the EEPROM */
418 	if (e1000_acquire_eeprom(hw)) {
419 		E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
420 		return 1;
421 	}
422 
423 	/* Perform the programming operation */
424 	if (e1000_spi_eeprom_dump(hw, dest, offset, length, TRUE) < 0) {
425 		E1000_ERR(hw->nic, "Interrupted!\n");
426 		e1000_release_eeprom(hw);
427 		return 1;
428 	}
429 
430 	e1000_release_eeprom(hw);
431 	printf("%s: ===== EEPROM DUMP COMPLETE =====\n", hw->nic->name);
432 	return 0;
433 }
434 
435 static int do_e1000_spi_program(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
436 		int argc, char * const argv[])
437 {
438 	unsigned int length;
439 	const void *source;
440 	u16 offset;
441 
442 	if (argc != 3) {
443 		cmd_usage(cmdtp);
444 		return 1;
445 	}
446 
447 	/* Parse the arguments */
448 	source = (const void *)simple_strtoul(argv[0], NULL, 16);
449 	offset = simple_strtoul(argv[1], NULL, 0);
450 	length = simple_strtoul(argv[2], NULL, 0);
451 
452 	/* Acquire the EEPROM */
453 	if (e1000_acquire_eeprom(hw)) {
454 		E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
455 		return 1;
456 	}
457 
458 	/* Perform the programming operation */
459 	if (e1000_spi_eeprom_program(hw, source, offset, length, TRUE) < 0) {
460 		E1000_ERR(hw->nic, "Interrupted!\n");
461 		e1000_release_eeprom(hw);
462 		return 1;
463 	}
464 
465 	e1000_release_eeprom(hw);
466 	printf("%s: ===== EEPROM PROGRAMMED =====\n", hw->nic->name);
467 	return 0;
468 }
469 
470 static int do_e1000_spi_checksum(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
471 		int argc, char * const argv[])
472 {
473 	uint16_t i, length, checksum = 0, checksum_reg;
474 	uint16_t *buffer;
475 	boolean_t upd;
476 
477 	if (argc == 0)
478 		upd = 0;
479 	else if ((argc == 1) && !strcmp(argv[0], "update"))
480 		upd = 1;
481 	else {
482 		cmd_usage(cmdtp);
483 		return 1;
484 	}
485 
486 	/* Allocate a temporary buffer */
487 	length = sizeof(uint16_t) * (EEPROM_CHECKSUM_REG + 1);
488 	buffer = malloc(length);
489 	if (!buffer) {
490 		E1000_ERR(hw->nic, "Unable to allocate EEPROM buffer!\n");
491 		return 1;
492 	}
493 
494 	/* Acquire the EEPROM */
495 	if (e1000_acquire_eeprom(hw)) {
496 		E1000_ERR(hw->nic, "EEPROM SPI cannot be acquired!\n");
497 		return 1;
498 	}
499 
500 	/* Read the EEPROM */
501 	if (e1000_spi_eeprom_dump(hw, buffer, 0, length, TRUE) < 0) {
502 		E1000_ERR(hw->nic, "Interrupted!\n");
503 		e1000_release_eeprom(hw);
504 		return 1;
505 	}
506 
507 	/* Compute the checksum and read the expected value */
508 	for (i = 0; i < EEPROM_CHECKSUM_REG; i++)
509 		checksum += le16_to_cpu(buffer[i]);
510 	checksum = ((uint16_t)EEPROM_SUM) - checksum;
511 	checksum_reg = le16_to_cpu(buffer[i]);
512 
513 	/* Verify it! */
514 	if (checksum_reg == checksum) {
515 		printf("%s: INFO: EEPROM checksum is correct! (0x%04hx)\n",
516 				hw->nic->name, checksum);
517 		e1000_release_eeprom(hw);
518 		return 0;
519 	}
520 
521 	/* Hrm, verification failed, print an error */
522 	E1000_ERR(hw->nic, "EEPROM checksum is incorrect!\n");
523 	E1000_ERR(hw->nic, "  ...register was 0x%04hx, calculated 0x%04hx\n",
524 			checksum_reg, checksum);
525 
526 	/* If they didn't ask us to update it, just return an error */
527 	if (!upd) {
528 		e1000_release_eeprom(hw);
529 		return 1;
530 	}
531 
532 	/* Ok, correct it! */
533 	printf("%s: Reprogramming the EEPROM checksum...\n", hw->nic->name);
534 	buffer[i] = cpu_to_le16(checksum);
535 	if (e1000_spi_eeprom_program(hw, &buffer[i], i * sizeof(uint16_t),
536 			sizeof(uint16_t), TRUE)) {
537 		E1000_ERR(hw->nic, "Interrupted!\n");
538 		e1000_release_eeprom(hw);
539 		return 1;
540 	}
541 
542 	e1000_release_eeprom(hw);
543 	return 0;
544 }
545 
546 int do_e1000_spi(cmd_tbl_t *cmdtp, struct e1000_hw *hw,
547 		int argc, char * const argv[])
548 {
549 	if (argc < 1) {
550 		cmd_usage(cmdtp);
551 		return 1;
552 	}
553 
554 	/* Make sure it has an SPI chip */
555 	if (hw->eeprom.type != e1000_eeprom_spi) {
556 		E1000_ERR(hw->nic, "No attached SPI EEPROM found!\n");
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