1 /*
2  * Copyright 2019 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  */
23 
24 #include "amdgpu_ras_eeprom.h"
25 #include "amdgpu.h"
26 #include "amdgpu_ras.h"
27 #include <linux/bits.h>
28 #include "atom.h"
29 
30 #define EEPROM_I2C_TARGET_ADDR_VEGA20		0xA0
31 #define EEPROM_I2C_TARGET_ADDR_ARCTURUS		0xA8
32 #define EEPROM_I2C_TARGET_ADDR_ARCTURUS_D342	0xA0
33 
34 /*
35  * The 2 macros bellow represent the actual size in bytes that
36  * those entities occupy in the EEPROM memory.
37  * EEPROM_TABLE_RECORD_SIZE is different than sizeof(eeprom_table_record) which
38  * uses uint64 to store 6b fields such as retired_page.
39  */
40 #define EEPROM_TABLE_HEADER_SIZE 20
41 #define EEPROM_TABLE_RECORD_SIZE 24
42 
43 #define EEPROM_ADDRESS_SIZE 0x2
44 
45 /* Table hdr is 'AMDR' */
46 #define EEPROM_TABLE_HDR_VAL 0x414d4452
47 #define EEPROM_TABLE_VER 0x00010000
48 
49 /* Bad GPU tag ‘BADG’ */
50 #define EEPROM_TABLE_HDR_BAD 0x42414447
51 
52 /* Assume 2 Mbit size */
53 #define EEPROM_SIZE_BYTES 256000
54 #define EEPROM_PAGE__SIZE_BYTES 256
55 #define EEPROM_HDR_START 0
56 #define EEPROM_RECORD_START (EEPROM_HDR_START + EEPROM_TABLE_HEADER_SIZE)
57 #define EEPROM_MAX_RECORD_NUM ((EEPROM_SIZE_BYTES - EEPROM_TABLE_HEADER_SIZE) / EEPROM_TABLE_RECORD_SIZE)
58 #define EEPROM_ADDR_MSB_MASK GENMASK(17, 8)
59 
60 #define to_amdgpu_device(x) (container_of(x, struct amdgpu_ras, eeprom_control))->adev
61 
62 static bool __is_ras_eeprom_supported(struct amdgpu_device *adev)
63 {
64 	if ((adev->asic_type == CHIP_VEGA20) ||
65 	    (adev->asic_type == CHIP_ARCTURUS))
66 		return true;
67 
68 	return false;
69 }
70 
71 static bool __get_eeprom_i2c_addr_arct(struct amdgpu_device *adev,
72 				       uint16_t *i2c_addr)
73 {
74 	struct atom_context *atom_ctx = adev->mode_info.atom_context;
75 
76 	if (!i2c_addr || !atom_ctx)
77 		return false;
78 
79 	if (strnstr(atom_ctx->vbios_version,
80 	            "D342",
81 		    sizeof(atom_ctx->vbios_version)))
82 		*i2c_addr = EEPROM_I2C_TARGET_ADDR_ARCTURUS_D342;
83 	else
84 		*i2c_addr = EEPROM_I2C_TARGET_ADDR_ARCTURUS;
85 
86 	return true;
87 }
88 
89 static bool __get_eeprom_i2c_addr(struct amdgpu_device *adev,
90 				  uint16_t *i2c_addr)
91 {
92 	if (!i2c_addr)
93 		return false;
94 
95 	switch (adev->asic_type) {
96 	case CHIP_VEGA20:
97 		*i2c_addr = EEPROM_I2C_TARGET_ADDR_VEGA20;
98 		break;
99 
100 	case CHIP_ARCTURUS:
101 		return __get_eeprom_i2c_addr_arct(adev, i2c_addr);
102 
103 	default:
104 		return false;
105 	}
106 
107 	return true;
108 }
109 
110 static void __encode_table_header_to_buff(struct amdgpu_ras_eeprom_table_header *hdr,
111 					  unsigned char *buff)
112 {
113 	uint32_t *pp = (uint32_t *) buff;
114 
115 	pp[0] = cpu_to_le32(hdr->header);
116 	pp[1] = cpu_to_le32(hdr->version);
117 	pp[2] = cpu_to_le32(hdr->first_rec_offset);
118 	pp[3] = cpu_to_le32(hdr->tbl_size);
119 	pp[4] = cpu_to_le32(hdr->checksum);
120 }
121 
122 static void __decode_table_header_from_buff(struct amdgpu_ras_eeprom_table_header *hdr,
123 					  unsigned char *buff)
124 {
125 	uint32_t *pp = (uint32_t *)buff;
126 
127 	hdr->header	      = le32_to_cpu(pp[0]);
128 	hdr->version	      = le32_to_cpu(pp[1]);
129 	hdr->first_rec_offset = le32_to_cpu(pp[2]);
130 	hdr->tbl_size	      = le32_to_cpu(pp[3]);
131 	hdr->checksum	      = le32_to_cpu(pp[4]);
132 }
133 
134 static int __update_table_header(struct amdgpu_ras_eeprom_control *control,
135 				 unsigned char *buff)
136 {
137 	int ret = 0;
138 	struct amdgpu_device *adev = to_amdgpu_device(control);
139 	struct i2c_msg msg = {
140 			.addr	= 0,
141 			.flags	= 0,
142 			.len	= EEPROM_ADDRESS_SIZE + EEPROM_TABLE_HEADER_SIZE,
143 			.buf	= buff,
144 	};
145 
146 
147 	*(uint16_t *)buff = EEPROM_HDR_START;
148 	__encode_table_header_to_buff(&control->tbl_hdr, buff + EEPROM_ADDRESS_SIZE);
149 
150 	msg.addr = control->i2c_address;
151 
152 	/* i2c may be unstable in gpu reset */
153 	down_read(&adev->reset_sem);
154 	ret = i2c_transfer(&adev->pm.smu_i2c, &msg, 1);
155 	up_read(&adev->reset_sem);
156 
157 	if (ret < 1)
158 		DRM_ERROR("Failed to write EEPROM table header, ret:%d", ret);
159 
160 	return ret;
161 }
162 
163 static uint32_t  __calc_hdr_byte_sum(struct amdgpu_ras_eeprom_control *control)
164 {
165 	int i;
166 	uint32_t tbl_sum = 0;
167 
168 	/* Header checksum, skip checksum field in the calculation */
169 	for (i = 0; i < sizeof(control->tbl_hdr) - sizeof(control->tbl_hdr.checksum); i++)
170 		tbl_sum += *(((unsigned char *)&control->tbl_hdr) + i);
171 
172 	return tbl_sum;
173 }
174 
175 static uint32_t  __calc_recs_byte_sum(struct eeprom_table_record *records,
176 				      int num)
177 {
178 	int i, j;
179 	uint32_t tbl_sum = 0;
180 
181 	/* Records checksum */
182 	for (i = 0; i < num; i++) {
183 		struct eeprom_table_record *record = &records[i];
184 
185 		for (j = 0; j < sizeof(*record); j++) {
186 			tbl_sum += *(((unsigned char *)record) + j);
187 		}
188 	}
189 
190 	return tbl_sum;
191 }
192 
193 static inline uint32_t  __calc_tbl_byte_sum(struct amdgpu_ras_eeprom_control *control,
194 				  struct eeprom_table_record *records, int num)
195 {
196 	return __calc_hdr_byte_sum(control) + __calc_recs_byte_sum(records, num);
197 }
198 
199 /* Checksum = 256 -((sum of all table entries) mod 256) */
200 static void __update_tbl_checksum(struct amdgpu_ras_eeprom_control *control,
201 				  struct eeprom_table_record *records, int num,
202 				  uint32_t old_hdr_byte_sum)
203 {
204 	/*
205 	 * This will update the table sum with new records.
206 	 *
207 	 * TODO: What happens when the EEPROM table is to be wrapped around
208 	 * and old records from start will get overridden.
209 	 */
210 
211 	/* need to recalculate updated header byte sum */
212 	control->tbl_byte_sum -= old_hdr_byte_sum;
213 	control->tbl_byte_sum += __calc_tbl_byte_sum(control, records, num);
214 
215 	control->tbl_hdr.checksum = 256 - (control->tbl_byte_sum % 256);
216 }
217 
218 /* table sum mod 256 + checksum must equals 256 */
219 static bool __validate_tbl_checksum(struct amdgpu_ras_eeprom_control *control,
220 			    struct eeprom_table_record *records, int num)
221 {
222 	control->tbl_byte_sum = __calc_tbl_byte_sum(control, records, num);
223 
224 	if (control->tbl_hdr.checksum + (control->tbl_byte_sum % 256) != 256) {
225 		DRM_WARN("Checksum mismatch, checksum: %u ", control->tbl_hdr.checksum);
226 		return false;
227 	}
228 
229 	return true;
230 }
231 
232 static int amdgpu_ras_eeprom_correct_header_tag(
233 				struct amdgpu_ras_eeprom_control *control,
234 				uint32_t header)
235 {
236 	unsigned char buff[EEPROM_ADDRESS_SIZE + EEPROM_TABLE_HEADER_SIZE];
237 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
238 	int ret = 0;
239 
240 	memset(buff, 0, EEPROM_ADDRESS_SIZE + EEPROM_TABLE_HEADER_SIZE);
241 
242 	mutex_lock(&control->tbl_mutex);
243 	hdr->header = header;
244 	ret = __update_table_header(control, buff);
245 	mutex_unlock(&control->tbl_mutex);
246 
247 	return ret;
248 }
249 
250 int amdgpu_ras_eeprom_reset_table(struct amdgpu_ras_eeprom_control *control)
251 {
252 	unsigned char buff[EEPROM_ADDRESS_SIZE + EEPROM_TABLE_HEADER_SIZE] = { 0 };
253 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
254 	int ret = 0;
255 
256 	mutex_lock(&control->tbl_mutex);
257 
258 	hdr->header = EEPROM_TABLE_HDR_VAL;
259 	hdr->version = EEPROM_TABLE_VER;
260 	hdr->first_rec_offset = EEPROM_RECORD_START;
261 	hdr->tbl_size = EEPROM_TABLE_HEADER_SIZE;
262 
263 	control->tbl_byte_sum = 0;
264 	__update_tbl_checksum(control, NULL, 0, 0);
265 	control->next_addr = EEPROM_RECORD_START;
266 
267 	ret = __update_table_header(control, buff);
268 
269 	mutex_unlock(&control->tbl_mutex);
270 
271 	return ret;
272 
273 }
274 
275 int amdgpu_ras_eeprom_init(struct amdgpu_ras_eeprom_control *control,
276 			bool *exceed_err_limit)
277 {
278 	int ret = 0;
279 	struct amdgpu_device *adev = to_amdgpu_device(control);
280 	unsigned char buff[EEPROM_ADDRESS_SIZE + EEPROM_TABLE_HEADER_SIZE] = { 0 };
281 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
282 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
283 	struct i2c_msg msg = {
284 			.addr	= 0,
285 			.flags	= I2C_M_RD,
286 			.len	= EEPROM_ADDRESS_SIZE + EEPROM_TABLE_HEADER_SIZE,
287 			.buf	= buff,
288 	};
289 
290 	*exceed_err_limit = false;
291 
292 	if (!__is_ras_eeprom_supported(adev))
293 		return 0;
294 
295 	/* Verify i2c adapter is initialized */
296 	if (!adev->pm.smu_i2c.algo)
297 		return -ENOENT;
298 
299 	if (!__get_eeprom_i2c_addr(adev, &control->i2c_address))
300 		return -EINVAL;
301 
302 	mutex_init(&control->tbl_mutex);
303 
304 	msg.addr = control->i2c_address;
305 	/* Read/Create table header from EEPROM address 0 */
306 	ret = i2c_transfer(&adev->pm.smu_i2c, &msg, 1);
307 	if (ret < 1) {
308 		DRM_ERROR("Failed to read EEPROM table header, ret:%d", ret);
309 		return ret;
310 	}
311 
312 	__decode_table_header_from_buff(hdr, &buff[2]);
313 
314 	if (hdr->header == EEPROM_TABLE_HDR_VAL) {
315 		control->num_recs = (hdr->tbl_size - EEPROM_TABLE_HEADER_SIZE) /
316 				    EEPROM_TABLE_RECORD_SIZE;
317 		control->tbl_byte_sum = __calc_hdr_byte_sum(control);
318 		control->next_addr = EEPROM_RECORD_START;
319 
320 		DRM_DEBUG_DRIVER("Found existing EEPROM table with %d records",
321 				 control->num_recs);
322 
323 	} else if ((hdr->header == EEPROM_TABLE_HDR_BAD) &&
324 			(amdgpu_bad_page_threshold != 0)) {
325 		if (ras->bad_page_cnt_threshold > control->num_recs) {
326 			dev_info(adev->dev, "Using one valid bigger bad page "
327 				"threshold and correcting eeprom header tag.\n");
328 			ret = amdgpu_ras_eeprom_correct_header_tag(control,
329 							EEPROM_TABLE_HDR_VAL);
330 		} else {
331 			*exceed_err_limit = true;
332 			dev_err(adev->dev, "Exceeding the bad_page_threshold parameter, "
333 				"disabling the GPU.\n");
334 		}
335 	} else {
336 		DRM_INFO("Creating new EEPROM table");
337 
338 		ret = amdgpu_ras_eeprom_reset_table(control);
339 	}
340 
341 	return ret == 1 ? 0 : -EIO;
342 }
343 
344 static void __encode_table_record_to_buff(struct amdgpu_ras_eeprom_control *control,
345 					  struct eeprom_table_record *record,
346 					  unsigned char *buff)
347 {
348 	__le64 tmp = 0;
349 	int i = 0;
350 
351 	/* Next are all record fields according to EEPROM page spec in LE foramt */
352 	buff[i++] = record->err_type;
353 
354 	buff[i++] = record->bank;
355 
356 	tmp = cpu_to_le64(record->ts);
357 	memcpy(buff + i, &tmp, 8);
358 	i += 8;
359 
360 	tmp = cpu_to_le64((record->offset & 0xffffffffffff));
361 	memcpy(buff + i, &tmp, 6);
362 	i += 6;
363 
364 	buff[i++] = record->mem_channel;
365 	buff[i++] = record->mcumc_id;
366 
367 	tmp = cpu_to_le64((record->retired_page & 0xffffffffffff));
368 	memcpy(buff + i, &tmp, 6);
369 }
370 
371 static void __decode_table_record_from_buff(struct amdgpu_ras_eeprom_control *control,
372 					    struct eeprom_table_record *record,
373 					    unsigned char *buff)
374 {
375 	__le64 tmp = 0;
376 	int i =  0;
377 
378 	/* Next are all record fields according to EEPROM page spec in LE foramt */
379 	record->err_type = buff[i++];
380 
381 	record->bank = buff[i++];
382 
383 	memcpy(&tmp, buff + i, 8);
384 	record->ts = le64_to_cpu(tmp);
385 	i += 8;
386 
387 	memcpy(&tmp, buff + i, 6);
388 	record->offset = (le64_to_cpu(tmp) & 0xffffffffffff);
389 	i += 6;
390 
391 	record->mem_channel = buff[i++];
392 	record->mcumc_id = buff[i++];
393 
394 	memcpy(&tmp, buff + i,  6);
395 	record->retired_page = (le64_to_cpu(tmp) & 0xffffffffffff);
396 }
397 
398 /*
399  * When reaching end of EEPROM memory jump back to 0 record address
400  * When next record access will go beyond EEPROM page boundary modify bits A17/A8
401  * in I2C selector to go to next page
402  */
403 static uint32_t __correct_eeprom_dest_address(uint32_t curr_address)
404 {
405 	uint32_t next_address = curr_address + EEPROM_TABLE_RECORD_SIZE;
406 
407 	/* When all EEPROM memory used jump back to 0 address */
408 	if (next_address > EEPROM_SIZE_BYTES) {
409 		DRM_INFO("Reached end of EEPROM memory, jumping to 0 "
410 			 "and overriding old record");
411 		return EEPROM_RECORD_START;
412 	}
413 
414 	/*
415 	 * To check if we overflow page boundary  compare next address with
416 	 * current and see if bits 17/8 of the EEPROM address will change
417 	 * If they do start from the next 256b page
418 	 *
419 	 * https://www.st.com/resource/en/datasheet/m24m02-dr.pdf sec. 5.1.2
420 	 */
421 	if ((curr_address & EEPROM_ADDR_MSB_MASK) != (next_address & EEPROM_ADDR_MSB_MASK)) {
422 		DRM_DEBUG_DRIVER("Reached end of EEPROM memory page, jumping to next: %lx",
423 				(next_address & EEPROM_ADDR_MSB_MASK));
424 
425 		return  (next_address & EEPROM_ADDR_MSB_MASK);
426 	}
427 
428 	return curr_address;
429 }
430 
431 int amdgpu_ras_eeprom_check_err_threshold(
432 				struct amdgpu_ras_eeprom_control *control,
433 				bool *exceed_err_limit)
434 {
435 	struct amdgpu_device *adev = to_amdgpu_device(control);
436 	unsigned char buff[EEPROM_ADDRESS_SIZE +
437 			EEPROM_TABLE_HEADER_SIZE] = { 0 };
438 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
439 	struct i2c_msg msg = {
440 			.addr = control->i2c_address,
441 			.flags = I2C_M_RD,
442 			.len = EEPROM_ADDRESS_SIZE + EEPROM_TABLE_HEADER_SIZE,
443 			.buf = buff,
444 	};
445 	int ret;
446 
447 	*exceed_err_limit = false;
448 
449 	if (!__is_ras_eeprom_supported(adev))
450 		return 0;
451 
452 	/* read EEPROM table header */
453 	mutex_lock(&control->tbl_mutex);
454 	ret = i2c_transfer(&adev->pm.smu_i2c, &msg, 1);
455 	if (ret < 1) {
456 		dev_err(adev->dev, "Failed to read EEPROM table header.\n");
457 		goto err;
458 	}
459 
460 	__decode_table_header_from_buff(hdr, &buff[2]);
461 
462 	if (hdr->header == EEPROM_TABLE_HDR_BAD) {
463 		dev_warn(adev->dev, "This GPU is in BAD status.");
464 		dev_warn(adev->dev, "Please retire it or setting one bigger "
465 				"threshold value when reloading driver.\n");
466 		*exceed_err_limit = true;
467 	}
468 
469 err:
470 	mutex_unlock(&control->tbl_mutex);
471 	return 0;
472 }
473 
474 int amdgpu_ras_eeprom_process_recods(struct amdgpu_ras_eeprom_control *control,
475 					    struct eeprom_table_record *records,
476 					    bool write,
477 					    int num)
478 {
479 	int i, ret = 0;
480 	struct i2c_msg *msgs, *msg;
481 	unsigned char *buffs, *buff;
482 	struct eeprom_table_record *record;
483 	struct amdgpu_device *adev = to_amdgpu_device(control);
484 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
485 
486 	if (!__is_ras_eeprom_supported(adev))
487 		return 0;
488 
489 	buffs = kcalloc(num, EEPROM_ADDRESS_SIZE + EEPROM_TABLE_RECORD_SIZE,
490 			 GFP_KERNEL);
491 	if (!buffs)
492 		return -ENOMEM;
493 
494 	mutex_lock(&control->tbl_mutex);
495 
496 	msgs = kcalloc(num, sizeof(*msgs), GFP_KERNEL);
497 	if (!msgs) {
498 		ret = -ENOMEM;
499 		goto free_buff;
500 	}
501 
502 	/*
503 	 * If saved bad pages number exceeds the bad page threshold for
504 	 * the whole VRAM, update table header to mark the BAD GPU tag
505 	 * and schedule one ras recovery after eeprom write is done,
506 	 * this can avoid the missing for latest records.
507 	 *
508 	 * This new header will be picked up and checked in the bootup
509 	 * by ras recovery, which may break bootup process to notify
510 	 * user this GPU is in bad state and to retire such GPU for
511 	 * further check.
512 	 */
513 	if (write && (amdgpu_bad_page_threshold != 0) &&
514 		((control->num_recs + num) >= ras->bad_page_cnt_threshold)) {
515 		dev_warn(adev->dev,
516 			"Saved bad pages(%d) reaches threshold value(%d).\n",
517 			control->num_recs + num, ras->bad_page_cnt_threshold);
518 		control->tbl_hdr.header = EEPROM_TABLE_HDR_BAD;
519 	}
520 
521 	/* In case of overflow just start from beginning to not lose newest records */
522 	if (write && (control->next_addr + EEPROM_TABLE_RECORD_SIZE * num > EEPROM_SIZE_BYTES))
523 		control->next_addr = EEPROM_RECORD_START;
524 
525 	/*
526 	 * TODO Currently makes EEPROM writes for each record, this creates
527 	 * internal fragmentation. Optimized the code to do full page write of
528 	 * 256b
529 	 */
530 	for (i = 0; i < num; i++) {
531 		buff = &buffs[i * (EEPROM_ADDRESS_SIZE + EEPROM_TABLE_RECORD_SIZE)];
532 		record = &records[i];
533 		msg = &msgs[i];
534 
535 		control->next_addr = __correct_eeprom_dest_address(control->next_addr);
536 
537 		/*
538 		 * Update bits 16,17 of EEPROM address in I2C address by setting them
539 		 * to bits 1,2 of Device address byte
540 		 */
541 		msg->addr = control->i2c_address |
542 			        ((control->next_addr & EEPROM_ADDR_MSB_MASK) >> 15);
543 		msg->flags	= write ? 0 : I2C_M_RD;
544 		msg->len	= EEPROM_ADDRESS_SIZE + EEPROM_TABLE_RECORD_SIZE;
545 		msg->buf	= buff;
546 
547 		/* Insert the EEPROM dest addess, bits 0-15 */
548 		buff[0] = ((control->next_addr >> 8) & 0xff);
549 		buff[1] = (control->next_addr & 0xff);
550 
551 		/* EEPROM table content is stored in LE format */
552 		if (write)
553 			__encode_table_record_to_buff(control, record, buff + EEPROM_ADDRESS_SIZE);
554 
555 		/*
556 		 * The destination EEPROM address might need to be corrected to account
557 		 * for page or entire memory wrapping
558 		 */
559 		control->next_addr += EEPROM_TABLE_RECORD_SIZE;
560 	}
561 
562 	/* i2c may be unstable in gpu reset */
563 	down_read(&adev->reset_sem);
564 	ret = i2c_transfer(&adev->pm.smu_i2c, msgs, num);
565 	up_read(&adev->reset_sem);
566 
567 	if (ret < 1) {
568 		DRM_ERROR("Failed to process EEPROM table records, ret:%d", ret);
569 
570 		/* TODO Restore prev next EEPROM address ? */
571 		goto free_msgs;
572 	}
573 
574 
575 	if (!write) {
576 		for (i = 0; i < num; i++) {
577 			buff = &buffs[i*(EEPROM_ADDRESS_SIZE + EEPROM_TABLE_RECORD_SIZE)];
578 			record = &records[i];
579 
580 			__decode_table_record_from_buff(control, record, buff + EEPROM_ADDRESS_SIZE);
581 		}
582 	}
583 
584 	if (write) {
585 		uint32_t old_hdr_byte_sum = __calc_hdr_byte_sum(control);
586 
587 		/*
588 		 * Update table header with size and CRC and account for table
589 		 * wrap around where the assumption is that we treat it as empty
590 		 * table
591 		 *
592 		 * TODO - Check the assumption is correct
593 		 */
594 		control->num_recs += num;
595 		control->num_recs %= EEPROM_MAX_RECORD_NUM;
596 		control->tbl_hdr.tbl_size += EEPROM_TABLE_RECORD_SIZE * num;
597 		if (control->tbl_hdr.tbl_size > EEPROM_SIZE_BYTES)
598 			control->tbl_hdr.tbl_size = EEPROM_TABLE_HEADER_SIZE +
599 			control->num_recs * EEPROM_TABLE_RECORD_SIZE;
600 
601 		__update_tbl_checksum(control, records, num, old_hdr_byte_sum);
602 
603 		__update_table_header(control, buffs);
604 	} else if (!__validate_tbl_checksum(control, records, num)) {
605 		DRM_WARN("EEPROM Table checksum mismatch!");
606 		/* TODO Uncomment when EEPROM read/write is relliable */
607 		/* ret = -EIO; */
608 	}
609 
610 free_msgs:
611 	kfree(msgs);
612 
613 free_buff:
614 	kfree(buffs);
615 
616 	mutex_unlock(&control->tbl_mutex);
617 
618 	return ret == num ? 0 : -EIO;
619 }
620 
621 inline uint32_t amdgpu_ras_eeprom_get_record_max_length(void)
622 {
623 	return EEPROM_MAX_RECORD_NUM;
624 }
625 
626 /* Used for testing if bugs encountered */
627 #if 0
628 void amdgpu_ras_eeprom_test(struct amdgpu_ras_eeprom_control *control)
629 {
630 	int i;
631 	struct eeprom_table_record *recs = kcalloc(1, sizeof(*recs), GFP_KERNEL);
632 
633 	if (!recs)
634 		return;
635 
636 	for (i = 0; i < 1 ; i++) {
637 		recs[i].address = 0xdeadbeef;
638 		recs[i].retired_page = i;
639 	}
640 
641 	if (!amdgpu_ras_eeprom_process_recods(control, recs, true, 1)) {
642 
643 		memset(recs, 0, sizeof(*recs) * 1);
644 
645 		control->next_addr = EEPROM_RECORD_START;
646 
647 		if (!amdgpu_ras_eeprom_process_recods(control, recs, false, 1)) {
648 			for (i = 0; i < 1; i++)
649 				DRM_INFO("rec.address :0x%llx, rec.retired_page :%llu",
650 					 recs[i].address, recs[i].retired_page);
651 		} else
652 			DRM_ERROR("Failed in reading from table");
653 
654 	} else
655 		DRM_ERROR("Failed in writing to table");
656 }
657 #endif
658