xref: /freebsd/sys/dev/igc/igc_nvm.c (revision d7d962ead0b6e5e8a39202d0590022082bf5bfb6)
1 /*-
2  * Copyright 2021 Intel Corp
3  * Copyright 2021 Rubicon Communications, LLC (Netgate)
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <sys/cdefs.h>
8 __FBSDID("$FreeBSD$");
9 
10 #include "igc_api.h"
11 
12 static void igc_reload_nvm_generic(struct igc_hw *hw);
13 
14 /**
15  *  igc_init_nvm_ops_generic - Initialize NVM function pointers
16  *  @hw: pointer to the HW structure
17  *
18  *  Setups up the function pointers to no-op functions
19  **/
20 void igc_init_nvm_ops_generic(struct igc_hw *hw)
21 {
22 	struct igc_nvm_info *nvm = &hw->nvm;
23 	DEBUGFUNC("igc_init_nvm_ops_generic");
24 
25 	/* Initialize function pointers */
26 	nvm->ops.init_params = igc_null_ops_generic;
27 	nvm->ops.acquire = igc_null_ops_generic;
28 	nvm->ops.read = igc_null_read_nvm;
29 	nvm->ops.release = igc_null_nvm_generic;
30 	nvm->ops.reload = igc_reload_nvm_generic;
31 	nvm->ops.update = igc_null_ops_generic;
32 	nvm->ops.validate = igc_null_ops_generic;
33 	nvm->ops.write = igc_null_write_nvm;
34 }
35 
36 /**
37  *  igc_null_nvm_read - No-op function, return 0
38  *  @hw: pointer to the HW structure
39  *  @a: dummy variable
40  *  @b: dummy variable
41  *  @c: dummy variable
42  **/
43 s32 igc_null_read_nvm(struct igc_hw IGC_UNUSEDARG *hw,
44 			u16 IGC_UNUSEDARG a, u16 IGC_UNUSEDARG b,
45 			u16 IGC_UNUSEDARG *c)
46 {
47 	DEBUGFUNC("igc_null_read_nvm");
48 	return IGC_SUCCESS;
49 }
50 
51 /**
52  *  igc_null_nvm_generic - No-op function, return void
53  *  @hw: pointer to the HW structure
54  **/
55 void igc_null_nvm_generic(struct igc_hw IGC_UNUSEDARG *hw)
56 {
57 	DEBUGFUNC("igc_null_nvm_generic");
58 	return;
59 }
60 
61 /**
62  *  igc_null_write_nvm - No-op function, return 0
63  *  @hw: pointer to the HW structure
64  *  @a: dummy variable
65  *  @b: dummy variable
66  *  @c: dummy variable
67  **/
68 s32 igc_null_write_nvm(struct igc_hw IGC_UNUSEDARG *hw,
69 			 u16 IGC_UNUSEDARG a, u16 IGC_UNUSEDARG b,
70 			 u16 IGC_UNUSEDARG *c)
71 {
72 	DEBUGFUNC("igc_null_write_nvm");
73 	return IGC_SUCCESS;
74 }
75 
76 /**
77  *  igc_raise_eec_clk - Raise EEPROM clock
78  *  @hw: pointer to the HW structure
79  *  @eecd: pointer to the EEPROM
80  *
81  *  Enable/Raise the EEPROM clock bit.
82  **/
83 static void igc_raise_eec_clk(struct igc_hw *hw, u32 *eecd)
84 {
85 	*eecd = *eecd | IGC_EECD_SK;
86 	IGC_WRITE_REG(hw, IGC_EECD, *eecd);
87 	IGC_WRITE_FLUSH(hw);
88 	usec_delay(hw->nvm.delay_usec);
89 }
90 
91 /**
92  *  igc_lower_eec_clk - Lower EEPROM clock
93  *  @hw: pointer to the HW structure
94  *  @eecd: pointer to the EEPROM
95  *
96  *  Clear/Lower the EEPROM clock bit.
97  **/
98 static void igc_lower_eec_clk(struct igc_hw *hw, u32 *eecd)
99 {
100 	*eecd = *eecd & ~IGC_EECD_SK;
101 	IGC_WRITE_REG(hw, IGC_EECD, *eecd);
102 	IGC_WRITE_FLUSH(hw);
103 	usec_delay(hw->nvm.delay_usec);
104 }
105 
106 /**
107  *  igc_shift_out_eec_bits - Shift data bits our to the EEPROM
108  *  @hw: pointer to the HW structure
109  *  @data: data to send to the EEPROM
110  *  @count: number of bits to shift out
111  *
112  *  We need to shift 'count' bits out to the EEPROM.  So, the value in the
113  *  "data" parameter will be shifted out to the EEPROM one bit at a time.
114  *  In order to do this, "data" must be broken down into bits.
115  **/
116 static void igc_shift_out_eec_bits(struct igc_hw *hw, u16 data, u16 count)
117 {
118 	struct igc_nvm_info *nvm = &hw->nvm;
119 	u32 eecd = IGC_READ_REG(hw, IGC_EECD);
120 	u32 mask;
121 
122 	DEBUGFUNC("igc_shift_out_eec_bits");
123 
124 	mask = 0x01 << (count - 1);
125 	if (nvm->type == igc_nvm_eeprom_spi)
126 		eecd |= IGC_EECD_DO;
127 
128 	do {
129 		eecd &= ~IGC_EECD_DI;
130 
131 		if (data & mask)
132 			eecd |= IGC_EECD_DI;
133 
134 		IGC_WRITE_REG(hw, IGC_EECD, eecd);
135 		IGC_WRITE_FLUSH(hw);
136 
137 		usec_delay(nvm->delay_usec);
138 
139 		igc_raise_eec_clk(hw, &eecd);
140 		igc_lower_eec_clk(hw, &eecd);
141 
142 		mask >>= 1;
143 	} while (mask);
144 
145 	eecd &= ~IGC_EECD_DI;
146 	IGC_WRITE_REG(hw, IGC_EECD, eecd);
147 }
148 
149 /**
150  *  igc_shift_in_eec_bits - Shift data bits in from the EEPROM
151  *  @hw: pointer to the HW structure
152  *  @count: number of bits to shift in
153  *
154  *  In order to read a register from the EEPROM, we need to shift 'count' bits
155  *  in from the EEPROM.  Bits are "shifted in" by raising the clock input to
156  *  the EEPROM (setting the SK bit), and then reading the value of the data out
157  *  "DO" bit.  During this "shifting in" process the data in "DI" bit should
158  *  always be clear.
159  **/
160 static u16 igc_shift_in_eec_bits(struct igc_hw *hw, u16 count)
161 {
162 	u32 eecd;
163 	u32 i;
164 	u16 data;
165 
166 	DEBUGFUNC("igc_shift_in_eec_bits");
167 
168 	eecd = IGC_READ_REG(hw, IGC_EECD);
169 
170 	eecd &= ~(IGC_EECD_DO | IGC_EECD_DI);
171 	data = 0;
172 
173 	for (i = 0; i < count; i++) {
174 		data <<= 1;
175 		igc_raise_eec_clk(hw, &eecd);
176 
177 		eecd = IGC_READ_REG(hw, IGC_EECD);
178 
179 		eecd &= ~IGC_EECD_DI;
180 		if (eecd & IGC_EECD_DO)
181 			data |= 1;
182 
183 		igc_lower_eec_clk(hw, &eecd);
184 	}
185 
186 	return data;
187 }
188 
189 /**
190  *  igc_poll_eerd_eewr_done - Poll for EEPROM read/write completion
191  *  @hw: pointer to the HW structure
192  *  @ee_reg: EEPROM flag for polling
193  *
194  *  Polls the EEPROM status bit for either read or write completion based
195  *  upon the value of 'ee_reg'.
196  **/
197 s32 igc_poll_eerd_eewr_done(struct igc_hw *hw, int ee_reg)
198 {
199 	u32 attempts = 100000;
200 	u32 i, reg = 0;
201 
202 	DEBUGFUNC("igc_poll_eerd_eewr_done");
203 
204 	for (i = 0; i < attempts; i++) {
205 		if (ee_reg == IGC_NVM_POLL_READ)
206 			reg = IGC_READ_REG(hw, IGC_EERD);
207 		else
208 			reg = IGC_READ_REG(hw, IGC_EEWR);
209 
210 		if (reg & IGC_NVM_RW_REG_DONE)
211 			return IGC_SUCCESS;
212 
213 		usec_delay(5);
214 	}
215 
216 	return -IGC_ERR_NVM;
217 }
218 
219 /**
220  *  igc_acquire_nvm_generic - Generic request for access to EEPROM
221  *  @hw: pointer to the HW structure
222  *
223  *  Set the EEPROM access request bit and wait for EEPROM access grant bit.
224  *  Return successful if access grant bit set, else clear the request for
225  *  EEPROM access and return -IGC_ERR_NVM (-1).
226  **/
227 s32 igc_acquire_nvm_generic(struct igc_hw *hw)
228 {
229 	u32 eecd = IGC_READ_REG(hw, IGC_EECD);
230 	s32 timeout = IGC_NVM_GRANT_ATTEMPTS;
231 
232 	DEBUGFUNC("igc_acquire_nvm_generic");
233 
234 	IGC_WRITE_REG(hw, IGC_EECD, eecd | IGC_EECD_REQ);
235 	eecd = IGC_READ_REG(hw, IGC_EECD);
236 
237 	while (timeout) {
238 		if (eecd & IGC_EECD_GNT)
239 			break;
240 		usec_delay(5);
241 		eecd = IGC_READ_REG(hw, IGC_EECD);
242 		timeout--;
243 	}
244 
245 	if (!timeout) {
246 		eecd &= ~IGC_EECD_REQ;
247 		IGC_WRITE_REG(hw, IGC_EECD, eecd);
248 		DEBUGOUT("Could not acquire NVM grant\n");
249 		return -IGC_ERR_NVM;
250 	}
251 
252 	return IGC_SUCCESS;
253 }
254 
255 /**
256  *  igc_standby_nvm - Return EEPROM to standby state
257  *  @hw: pointer to the HW structure
258  *
259  *  Return the EEPROM to a standby state.
260  **/
261 static void igc_standby_nvm(struct igc_hw *hw)
262 {
263 	struct igc_nvm_info *nvm = &hw->nvm;
264 	u32 eecd = IGC_READ_REG(hw, IGC_EECD);
265 
266 	DEBUGFUNC("igc_standby_nvm");
267 
268 	if (nvm->type == igc_nvm_eeprom_spi) {
269 		/* Toggle CS to flush commands */
270 		eecd |= IGC_EECD_CS;
271 		IGC_WRITE_REG(hw, IGC_EECD, eecd);
272 		IGC_WRITE_FLUSH(hw);
273 		usec_delay(nvm->delay_usec);
274 		eecd &= ~IGC_EECD_CS;
275 		IGC_WRITE_REG(hw, IGC_EECD, eecd);
276 		IGC_WRITE_FLUSH(hw);
277 		usec_delay(nvm->delay_usec);
278 	}
279 }
280 
281 /**
282  *  igc_stop_nvm - Terminate EEPROM command
283  *  @hw: pointer to the HW structure
284  *
285  *  Terminates the current command by inverting the EEPROM's chip select pin.
286  **/
287 static void igc_stop_nvm(struct igc_hw *hw)
288 {
289 	u32 eecd;
290 
291 	DEBUGFUNC("igc_stop_nvm");
292 
293 	eecd = IGC_READ_REG(hw, IGC_EECD);
294 	if (hw->nvm.type == igc_nvm_eeprom_spi) {
295 		/* Pull CS high */
296 		eecd |= IGC_EECD_CS;
297 		igc_lower_eec_clk(hw, &eecd);
298 	}
299 }
300 
301 /**
302  *  igc_release_nvm_generic - Release exclusive access to EEPROM
303  *  @hw: pointer to the HW structure
304  *
305  *  Stop any current commands to the EEPROM and clear the EEPROM request bit.
306  **/
307 void igc_release_nvm_generic(struct igc_hw *hw)
308 {
309 	u32 eecd;
310 
311 	DEBUGFUNC("igc_release_nvm_generic");
312 
313 	igc_stop_nvm(hw);
314 
315 	eecd = IGC_READ_REG(hw, IGC_EECD);
316 	eecd &= ~IGC_EECD_REQ;
317 	IGC_WRITE_REG(hw, IGC_EECD, eecd);
318 }
319 
320 /**
321  *  igc_ready_nvm_eeprom - Prepares EEPROM for read/write
322  *  @hw: pointer to the HW structure
323  *
324  *  Setups the EEPROM for reading and writing.
325  **/
326 static s32 igc_ready_nvm_eeprom(struct igc_hw *hw)
327 {
328 	struct igc_nvm_info *nvm = &hw->nvm;
329 	u32 eecd = IGC_READ_REG(hw, IGC_EECD);
330 	u8 spi_stat_reg;
331 
332 	DEBUGFUNC("igc_ready_nvm_eeprom");
333 
334 	if (nvm->type == igc_nvm_eeprom_spi) {
335 		u16 timeout = NVM_MAX_RETRY_SPI;
336 
337 		/* Clear SK and CS */
338 		eecd &= ~(IGC_EECD_CS | IGC_EECD_SK);
339 		IGC_WRITE_REG(hw, IGC_EECD, eecd);
340 		IGC_WRITE_FLUSH(hw);
341 		usec_delay(1);
342 
343 		/* Read "Status Register" repeatedly until the LSB is cleared.
344 		 * The EEPROM will signal that the command has been completed
345 		 * by clearing bit 0 of the internal status register.  If it's
346 		 * not cleared within 'timeout', then error out.
347 		 */
348 		while (timeout) {
349 			igc_shift_out_eec_bits(hw, NVM_RDSR_OPCODE_SPI,
350 						 hw->nvm.opcode_bits);
351 			spi_stat_reg = (u8)igc_shift_in_eec_bits(hw, 8);
352 			if (!(spi_stat_reg & NVM_STATUS_RDY_SPI))
353 				break;
354 
355 			usec_delay(5);
356 			igc_standby_nvm(hw);
357 			timeout--;
358 		}
359 
360 		if (!timeout) {
361 			DEBUGOUT("SPI NVM Status error\n");
362 			return -IGC_ERR_NVM;
363 		}
364 	}
365 
366 	return IGC_SUCCESS;
367 }
368 
369 /**
370  *  igc_read_nvm_eerd - Reads EEPROM using EERD register
371  *  @hw: pointer to the HW structure
372  *  @offset: offset of word in the EEPROM to read
373  *  @words: number of words to read
374  *  @data: word read from the EEPROM
375  *
376  *  Reads a 16 bit word from the EEPROM using the EERD register.
377  **/
378 s32 igc_read_nvm_eerd(struct igc_hw *hw, u16 offset, u16 words, u16 *data)
379 {
380 	struct igc_nvm_info *nvm = &hw->nvm;
381 	u32 i, eerd = 0;
382 	s32 ret_val = IGC_SUCCESS;
383 
384 	DEBUGFUNC("igc_read_nvm_eerd");
385 
386 	/* A check for invalid values:  offset too large, too many words,
387 	 * too many words for the offset, and not enough words.
388 	 */
389 	if ((offset >= nvm->word_size) || (words > (nvm->word_size - offset)) ||
390 	    (words == 0)) {
391 		DEBUGOUT("nvm parameter(s) out of bounds\n");
392 		return -IGC_ERR_NVM;
393 	}
394 
395 	for (i = 0; i < words; i++) {
396 		eerd = ((offset + i) << IGC_NVM_RW_ADDR_SHIFT) +
397 		       IGC_NVM_RW_REG_START;
398 
399 		IGC_WRITE_REG(hw, IGC_EERD, eerd);
400 		ret_val = igc_poll_eerd_eewr_done(hw, IGC_NVM_POLL_READ);
401 		if (ret_val)
402 			break;
403 
404 		data[i] = (IGC_READ_REG(hw, IGC_EERD) >>
405 			   IGC_NVM_RW_REG_DATA);
406 	}
407 
408 	if (ret_val)
409 		DEBUGOUT1("NVM read error: %d\n", ret_val);
410 
411 	return ret_val;
412 }
413 
414 /**
415  *  igc_write_nvm_spi - Write to EEPROM using SPI
416  *  @hw: pointer to the HW structure
417  *  @offset: offset within the EEPROM to be written to
418  *  @words: number of words to write
419  *  @data: 16 bit word(s) to be written to the EEPROM
420  *
421  *  Writes data to EEPROM at offset using SPI interface.
422  *
423  *  If igc_update_nvm_checksum is not called after this function , the
424  *  EEPROM will most likely contain an invalid checksum.
425  **/
426 s32 igc_write_nvm_spi(struct igc_hw *hw, u16 offset, u16 words, u16 *data)
427 {
428 	struct igc_nvm_info *nvm = &hw->nvm;
429 	s32 ret_val = -IGC_ERR_NVM;
430 	u16 widx = 0;
431 
432 	DEBUGFUNC("igc_write_nvm_spi");
433 
434 	/* A check for invalid values:  offset too large, too many words,
435 	 * and not enough words.
436 	 */
437 	if ((offset >= nvm->word_size) || (words > (nvm->word_size - offset)) ||
438 	    (words == 0)) {
439 		DEBUGOUT("nvm parameter(s) out of bounds\n");
440 		return -IGC_ERR_NVM;
441 	}
442 
443 	while (widx < words) {
444 		u8 write_opcode = NVM_WRITE_OPCODE_SPI;
445 
446 		ret_val = nvm->ops.acquire(hw);
447 		if (ret_val)
448 			return ret_val;
449 
450 		ret_val = igc_ready_nvm_eeprom(hw);
451 		if (ret_val) {
452 			nvm->ops.release(hw);
453 			return ret_val;
454 		}
455 
456 		igc_standby_nvm(hw);
457 
458 		/* Send the WRITE ENABLE command (8 bit opcode) */
459 		igc_shift_out_eec_bits(hw, NVM_WREN_OPCODE_SPI,
460 					 nvm->opcode_bits);
461 
462 		igc_standby_nvm(hw);
463 
464 		/* Some SPI eeproms use the 8th address bit embedded in the
465 		 * opcode
466 		 */
467 		if ((nvm->address_bits == 8) && (offset >= 128))
468 			write_opcode |= NVM_A8_OPCODE_SPI;
469 
470 		/* Send the Write command (8-bit opcode + addr) */
471 		igc_shift_out_eec_bits(hw, write_opcode, nvm->opcode_bits);
472 		igc_shift_out_eec_bits(hw, (u16)((offset + widx) * 2),
473 					 nvm->address_bits);
474 
475 		/* Loop to allow for up to whole page write of eeprom */
476 		while (widx < words) {
477 			u16 word_out = data[widx];
478 			word_out = (word_out >> 8) | (word_out << 8);
479 			igc_shift_out_eec_bits(hw, word_out, 16);
480 			widx++;
481 
482 			if ((((offset + widx) * 2) % nvm->page_size) == 0) {
483 				igc_standby_nvm(hw);
484 				break;
485 			}
486 		}
487 		msec_delay(10);
488 		nvm->ops.release(hw);
489 	}
490 
491 	return ret_val;
492 }
493 
494 /**
495  *  igc_read_pba_string_generic - Read device part number
496  *  @hw: pointer to the HW structure
497  *  @pba_num: pointer to device part number
498  *  @pba_num_size: size of part number buffer
499  *
500  *  Reads the product board assembly (PBA) number from the EEPROM and stores
501  *  the value in pba_num.
502  **/
503 s32 igc_read_pba_string_generic(struct igc_hw *hw, u8 *pba_num,
504 				  u32 pba_num_size)
505 {
506 	s32 ret_val;
507 	u16 nvm_data;
508 	u16 pba_ptr;
509 	u16 offset;
510 	u16 length;
511 
512 	DEBUGFUNC("igc_read_pba_string_generic");
513 
514 	if (pba_num == NULL) {
515 		DEBUGOUT("PBA string buffer was null\n");
516 		return -IGC_ERR_INVALID_ARGUMENT;
517 	}
518 
519 	ret_val = hw->nvm.ops.read(hw, NVM_PBA_OFFSET_0, 1, &nvm_data);
520 	if (ret_val) {
521 		DEBUGOUT("NVM Read Error\n");
522 		return ret_val;
523 	}
524 
525 	ret_val = hw->nvm.ops.read(hw, NVM_PBA_OFFSET_1, 1, &pba_ptr);
526 	if (ret_val) {
527 		DEBUGOUT("NVM Read Error\n");
528 		return ret_val;
529 	}
530 
531 	/* if nvm_data is not ptr guard the PBA must be in legacy format which
532 	 * means pba_ptr is actually our second data word for the PBA number
533 	 * and we can decode it into an ascii string
534 	 */
535 	if (nvm_data != NVM_PBA_PTR_GUARD) {
536 		DEBUGOUT("NVM PBA number is not stored as string\n");
537 
538 		/* make sure callers buffer is big enough to store the PBA */
539 		if (pba_num_size < IGC_PBANUM_LENGTH) {
540 			DEBUGOUT("PBA string buffer too small\n");
541 			return IGC_ERR_NO_SPACE;
542 		}
543 
544 		/* extract hex string from data and pba_ptr */
545 		pba_num[0] = (nvm_data >> 12) & 0xF;
546 		pba_num[1] = (nvm_data >> 8) & 0xF;
547 		pba_num[2] = (nvm_data >> 4) & 0xF;
548 		pba_num[3] = nvm_data & 0xF;
549 		pba_num[4] = (pba_ptr >> 12) & 0xF;
550 		pba_num[5] = (pba_ptr >> 8) & 0xF;
551 		pba_num[6] = '-';
552 		pba_num[7] = 0;
553 		pba_num[8] = (pba_ptr >> 4) & 0xF;
554 		pba_num[9] = pba_ptr & 0xF;
555 
556 		/* put a null character on the end of our string */
557 		pba_num[10] = '\0';
558 
559 		/* switch all the data but the '-' to hex char */
560 		for (offset = 0; offset < 10; offset++) {
561 			if (pba_num[offset] < 0xA)
562 				pba_num[offset] += '0';
563 			else if (pba_num[offset] < 0x10)
564 				pba_num[offset] += 'A' - 0xA;
565 		}
566 
567 		return IGC_SUCCESS;
568 	}
569 
570 	ret_val = hw->nvm.ops.read(hw, pba_ptr, 1, &length);
571 	if (ret_val) {
572 		DEBUGOUT("NVM Read Error\n");
573 		return ret_val;
574 	}
575 
576 	if (length == 0xFFFF || length == 0) {
577 		DEBUGOUT("NVM PBA number section invalid length\n");
578 		return -IGC_ERR_NVM_PBA_SECTION;
579 	}
580 	/* check if pba_num buffer is big enough */
581 	if (pba_num_size < (((u32)length * 2) - 1)) {
582 		DEBUGOUT("PBA string buffer too small\n");
583 		return -IGC_ERR_NO_SPACE;
584 	}
585 
586 	/* trim pba length from start of string */
587 	pba_ptr++;
588 	length--;
589 
590 	for (offset = 0; offset < length; offset++) {
591 		ret_val = hw->nvm.ops.read(hw, pba_ptr + offset, 1, &nvm_data);
592 		if (ret_val) {
593 			DEBUGOUT("NVM Read Error\n");
594 			return ret_val;
595 		}
596 		pba_num[offset * 2] = (u8)(nvm_data >> 8);
597 		pba_num[(offset * 2) + 1] = (u8)(nvm_data & 0xFF);
598 	}
599 	pba_num[offset * 2] = '\0';
600 
601 	return IGC_SUCCESS;
602 }
603 
604 
605 
606 
607 
608 /**
609  *  igc_read_mac_addr_generic - Read device MAC address
610  *  @hw: pointer to the HW structure
611  *
612  *  Reads the device MAC address from the EEPROM and stores the value.
613  *  Since devices with two ports use the same EEPROM, we increment the
614  *  last bit in the MAC address for the second port.
615  **/
616 s32 igc_read_mac_addr_generic(struct igc_hw *hw)
617 {
618 	u32 rar_high;
619 	u32 rar_low;
620 	u16 i;
621 
622 	rar_high = IGC_READ_REG(hw, IGC_RAH(0));
623 	rar_low = IGC_READ_REG(hw, IGC_RAL(0));
624 
625 	for (i = 0; i < IGC_RAL_MAC_ADDR_LEN; i++)
626 		hw->mac.perm_addr[i] = (u8)(rar_low >> (i*8));
627 
628 	for (i = 0; i < IGC_RAH_MAC_ADDR_LEN; i++)
629 		hw->mac.perm_addr[i+4] = (u8)(rar_high >> (i*8));
630 
631 	for (i = 0; i < ETH_ADDR_LEN; i++)
632 		hw->mac.addr[i] = hw->mac.perm_addr[i];
633 
634 	return IGC_SUCCESS;
635 }
636 
637 /**
638  *  igc_validate_nvm_checksum_generic - Validate EEPROM checksum
639  *  @hw: pointer to the HW structure
640  *
641  *  Calculates the EEPROM checksum by reading/adding each word of the EEPROM
642  *  and then verifies that the sum of the EEPROM is equal to 0xBABA.
643  **/
644 s32 igc_validate_nvm_checksum_generic(struct igc_hw *hw)
645 {
646 	s32 ret_val;
647 	u16 checksum = 0;
648 	u16 i, nvm_data;
649 
650 	DEBUGFUNC("igc_validate_nvm_checksum_generic");
651 
652 	for (i = 0; i < (NVM_CHECKSUM_REG + 1); i++) {
653 		ret_val = hw->nvm.ops.read(hw, i, 1, &nvm_data);
654 		if (ret_val) {
655 			DEBUGOUT("NVM Read Error\n");
656 			return ret_val;
657 		}
658 		checksum += nvm_data;
659 	}
660 
661 	if (checksum != (u16) NVM_SUM) {
662 		DEBUGOUT("NVM Checksum Invalid\n");
663 		return -IGC_ERR_NVM;
664 	}
665 
666 	return IGC_SUCCESS;
667 }
668 
669 /**
670  *  igc_update_nvm_checksum_generic - Update EEPROM checksum
671  *  @hw: pointer to the HW structure
672  *
673  *  Updates the EEPROM checksum by reading/adding each word of the EEPROM
674  *  up to the checksum.  Then calculates the EEPROM checksum and writes the
675  *  value to the EEPROM.
676  **/
677 s32 igc_update_nvm_checksum_generic(struct igc_hw *hw)
678 {
679 	s32 ret_val;
680 	u16 checksum = 0;
681 	u16 i, nvm_data;
682 
683 	DEBUGFUNC("igc_update_nvm_checksum");
684 
685 	for (i = 0; i < NVM_CHECKSUM_REG; i++) {
686 		ret_val = hw->nvm.ops.read(hw, i, 1, &nvm_data);
687 		if (ret_val) {
688 			DEBUGOUT("NVM Read Error while updating checksum.\n");
689 			return ret_val;
690 		}
691 		checksum += nvm_data;
692 	}
693 	checksum = (u16) NVM_SUM - checksum;
694 	ret_val = hw->nvm.ops.write(hw, NVM_CHECKSUM_REG, 1, &checksum);
695 	if (ret_val)
696 		DEBUGOUT("NVM Write Error while updating checksum.\n");
697 
698 	return ret_val;
699 }
700 
701 /**
702  *  igc_reload_nvm_generic - Reloads EEPROM
703  *  @hw: pointer to the HW structure
704  *
705  *  Reloads the EEPROM by setting the "Reinitialize from EEPROM" bit in the
706  *  extended control register.
707  **/
708 static void igc_reload_nvm_generic(struct igc_hw *hw)
709 {
710 	u32 ctrl_ext;
711 
712 	DEBUGFUNC("igc_reload_nvm_generic");
713 
714 	usec_delay(10);
715 	ctrl_ext = IGC_READ_REG(hw, IGC_CTRL_EXT);
716 	ctrl_ext |= IGC_CTRL_EXT_EE_RST;
717 	IGC_WRITE_REG(hw, IGC_CTRL_EXT, ctrl_ext);
718 	IGC_WRITE_FLUSH(hw);
719 }
720 
721 
722