xref: /linux/drivers/gpu/drm/amd/amdgpu/amdgpu_ras_eeprom.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
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 #include "amdgpu_eeprom.h"
30 #include "amdgpu_atomfirmware.h"
31 #include <linux/debugfs.h>
32 #include <linux/uaccess.h>
33 
34 #include "amdgpu_reset.h"
35 
36 /* These are memory addresses as would be seen by one or more EEPROM
37  * chips strung on the I2C bus, usually by manipulating pins 1-3 of a
38  * set of EEPROM devices. They form a continuous memory space.
39  *
40  * The I2C device address includes the device type identifier, 1010b,
41  * which is a reserved value and indicates that this is an I2C EEPROM
42  * device. It also includes the top 3 bits of the 19 bit EEPROM memory
43  * address, namely bits 18, 17, and 16. This makes up the 7 bit
44  * address sent on the I2C bus with bit 0 being the direction bit,
45  * which is not represented here, and sent by the hardware directly.
46  *
47  * For instance,
48  *   50h = 1010000b => device type identifier 1010b, bits 18:16 = 000b, address 0.
49  *   54h = 1010100b => --"--, bits 18:16 = 100b, address 40000h.
50  *   56h = 1010110b => --"--, bits 18:16 = 110b, address 60000h.
51  * Depending on the size of the I2C EEPROM device(s), bits 18:16 may
52  * address memory in a device or a device on the I2C bus, depending on
53  * the status of pins 1-3. See top of amdgpu_eeprom.c.
54  *
55  * The RAS table lives either at address 0 or address 40000h of EEPROM.
56  */
57 #define EEPROM_I2C_MADDR_0      0x0
58 #define EEPROM_I2C_MADDR_4      0x40000
59 
60 /*
61  * The 2 macros bellow represent the actual size in bytes that
62  * those entities occupy in the EEPROM memory.
63  * RAS_TABLE_RECORD_SIZE is different than sizeof(eeprom_table_record) which
64  * uses uint64 to store 6b fields such as retired_page.
65  */
66 #define RAS_TABLE_HEADER_SIZE   20
67 #define RAS_TABLE_RECORD_SIZE   24
68 
69 /* Table hdr is 'AMDR' */
70 #define RAS_TABLE_HDR_VAL       0x414d4452
71 
72 /* Bad GPU tag ‘BADG’ */
73 #define RAS_TABLE_HDR_BAD       0x42414447
74 
75 /*
76  * EEPROM Table structure v1
77  * ---------------------------------
78  * |                               |
79  * |     EEPROM TABLE HEADER       |
80  * |      ( size 20 Bytes )        |
81  * |                               |
82  * ---------------------------------
83  * |                               |
84  * |    BAD PAGE RECORD AREA       |
85  * |                               |
86  * ---------------------------------
87  */
88 
89 /* Assume 2-Mbit size EEPROM and take up the whole space. */
90 #define RAS_TBL_SIZE_BYTES      (256 * 1024)
91 #define RAS_TABLE_START         0
92 #define RAS_HDR_START           RAS_TABLE_START
93 #define RAS_RECORD_START        (RAS_HDR_START + RAS_TABLE_HEADER_SIZE)
94 #define RAS_MAX_RECORD_COUNT    ((RAS_TBL_SIZE_BYTES - RAS_TABLE_HEADER_SIZE) \
95 				 / RAS_TABLE_RECORD_SIZE)
96 
97 /*
98  * EEPROM Table structrue v2.1
99  * ---------------------------------
100  * |                               |
101  * |     EEPROM TABLE HEADER       |
102  * |      ( size 20 Bytes )        |
103  * |                               |
104  * ---------------------------------
105  * |                               |
106  * |     EEPROM TABLE RAS INFO     |
107  * | (available info size 4 Bytes) |
108  * |  ( reserved size 252 Bytes )  |
109  * |                               |
110  * ---------------------------------
111  * |                               |
112  * |     BAD PAGE RECORD AREA      |
113  * |                               |
114  * ---------------------------------
115  */
116 
117 /* EEPROM Table V2_1 */
118 #define RAS_TABLE_V2_1_INFO_SIZE       256
119 #define RAS_TABLE_V2_1_INFO_START      RAS_TABLE_HEADER_SIZE
120 #define RAS_RECORD_START_V2_1          (RAS_HDR_START + RAS_TABLE_HEADER_SIZE + \
121 					RAS_TABLE_V2_1_INFO_SIZE)
122 #define RAS_MAX_RECORD_COUNT_V2_1      ((RAS_TBL_SIZE_BYTES - RAS_TABLE_HEADER_SIZE - \
123 					RAS_TABLE_V2_1_INFO_SIZE) \
124 					/ RAS_TABLE_RECORD_SIZE)
125 
126 /* Given a zero-based index of an EEPROM RAS record, yields the EEPROM
127  * offset off of RAS_TABLE_START.  That is, this is something you can
128  * add to control->i2c_address, and then tell I2C layer to read
129  * from/write to there. _N is the so called absolute index,
130  * because it starts right after the table header.
131  */
132 #define RAS_INDEX_TO_OFFSET(_C, _N) ((_C)->ras_record_offset + \
133 				     (_N) * RAS_TABLE_RECORD_SIZE)
134 
135 #define RAS_OFFSET_TO_INDEX(_C, _O) (((_O) - \
136 				      (_C)->ras_record_offset) / RAS_TABLE_RECORD_SIZE)
137 
138 /* Given a 0-based relative record index, 0, 1, 2, ..., etc., off
139  * of "fri", return the absolute record index off of the end of
140  * the table header.
141  */
142 #define RAS_RI_TO_AI(_C, _I) (((_I) + (_C)->ras_fri) % \
143 			      (_C)->ras_max_record_count)
144 
145 #define RAS_NUM_RECS(_tbl_hdr)  (((_tbl_hdr)->tbl_size - \
146 				  RAS_TABLE_HEADER_SIZE) / RAS_TABLE_RECORD_SIZE)
147 
148 #define RAS_NUM_RECS_V2_1(_tbl_hdr)  (((_tbl_hdr)->tbl_size - \
149 				       RAS_TABLE_HEADER_SIZE - \
150 				       RAS_TABLE_V2_1_INFO_SIZE) / RAS_TABLE_RECORD_SIZE)
151 
152 #define to_amdgpu_device(x) ((container_of(x, struct amdgpu_ras, eeprom_control))->adev)
153 
154 static bool __is_ras_eeprom_supported(struct amdgpu_device *adev)
155 {
156 	switch (amdgpu_ip_version(adev, MP1_HWIP, 0)) {
157 	case IP_VERSION(11, 0, 2): /* VEGA20 and ARCTURUS */
158 	case IP_VERSION(11, 0, 7): /* Sienna cichlid */
159 	case IP_VERSION(13, 0, 0):
160 	case IP_VERSION(13, 0, 2): /* Aldebaran */
161 	case IP_VERSION(13, 0, 10):
162 		return true;
163 	case IP_VERSION(13, 0, 6):
164 		return (adev->gmc.is_app_apu) ? false : true;
165 	default:
166 		return false;
167 	}
168 }
169 
170 static bool __get_eeprom_i2c_addr(struct amdgpu_device *adev,
171 				  struct amdgpu_ras_eeprom_control *control)
172 {
173 	struct atom_context *atom_ctx = adev->mode_info.atom_context;
174 	u8 i2c_addr;
175 
176 	if (!control)
177 		return false;
178 
179 	if (amdgpu_atomfirmware_ras_rom_addr(adev, &i2c_addr)) {
180 		/* The address given by VBIOS is an 8-bit, wire-format
181 		 * address, i.e. the most significant byte.
182 		 *
183 		 * Normalize it to a 19-bit EEPROM address. Remove the
184 		 * device type identifier and make it a 7-bit address;
185 		 * then make it a 19-bit EEPROM address. See top of
186 		 * amdgpu_eeprom.c.
187 		 */
188 		i2c_addr = (i2c_addr & 0x0F) >> 1;
189 		control->i2c_address = ((u32) i2c_addr) << 16;
190 
191 		return true;
192 	}
193 
194 	switch (amdgpu_ip_version(adev, MP1_HWIP, 0)) {
195 	case IP_VERSION(11, 0, 2):
196 		/* VEGA20 and ARCTURUS */
197 		if (adev->asic_type == CHIP_VEGA20)
198 			control->i2c_address = EEPROM_I2C_MADDR_0;
199 		else if (strnstr(atom_ctx->vbios_pn,
200 				 "D342",
201 				 sizeof(atom_ctx->vbios_pn)))
202 			control->i2c_address = EEPROM_I2C_MADDR_0;
203 		else
204 			control->i2c_address = EEPROM_I2C_MADDR_4;
205 		return true;
206 	case IP_VERSION(11, 0, 7):
207 		control->i2c_address = EEPROM_I2C_MADDR_0;
208 		return true;
209 	case IP_VERSION(13, 0, 2):
210 		if (strnstr(atom_ctx->vbios_pn, "D673",
211 			    sizeof(atom_ctx->vbios_pn)))
212 			control->i2c_address = EEPROM_I2C_MADDR_4;
213 		else
214 			control->i2c_address = EEPROM_I2C_MADDR_0;
215 		return true;
216 	case IP_VERSION(13, 0, 0):
217 		if (strnstr(atom_ctx->vbios_pn, "D707",
218 			    sizeof(atom_ctx->vbios_pn)))
219 			control->i2c_address = EEPROM_I2C_MADDR_0;
220 		else
221 			control->i2c_address = EEPROM_I2C_MADDR_4;
222 		return true;
223 	case IP_VERSION(13, 0, 6):
224 	case IP_VERSION(13, 0, 10):
225 		control->i2c_address = EEPROM_I2C_MADDR_4;
226 		return true;
227 	default:
228 		return false;
229 	}
230 }
231 
232 static void
233 __encode_table_header_to_buf(struct amdgpu_ras_eeprom_table_header *hdr,
234 			     unsigned char *buf)
235 {
236 	u32 *pp = (uint32_t *)buf;
237 
238 	pp[0] = cpu_to_le32(hdr->header);
239 	pp[1] = cpu_to_le32(hdr->version);
240 	pp[2] = cpu_to_le32(hdr->first_rec_offset);
241 	pp[3] = cpu_to_le32(hdr->tbl_size);
242 	pp[4] = cpu_to_le32(hdr->checksum);
243 }
244 
245 static void
246 __decode_table_header_from_buf(struct amdgpu_ras_eeprom_table_header *hdr,
247 			       unsigned char *buf)
248 {
249 	u32 *pp = (uint32_t *)buf;
250 
251 	hdr->header	      = le32_to_cpu(pp[0]);
252 	hdr->version	      = le32_to_cpu(pp[1]);
253 	hdr->first_rec_offset = le32_to_cpu(pp[2]);
254 	hdr->tbl_size	      = le32_to_cpu(pp[3]);
255 	hdr->checksum	      = le32_to_cpu(pp[4]);
256 }
257 
258 static int __write_table_header(struct amdgpu_ras_eeprom_control *control)
259 {
260 	u8 buf[RAS_TABLE_HEADER_SIZE];
261 	struct amdgpu_device *adev = to_amdgpu_device(control);
262 	int res;
263 
264 	memset(buf, 0, sizeof(buf));
265 	__encode_table_header_to_buf(&control->tbl_hdr, buf);
266 
267 	/* i2c may be unstable in gpu reset */
268 	down_read(&adev->reset_domain->sem);
269 	res = amdgpu_eeprom_write(adev->pm.ras_eeprom_i2c_bus,
270 				  control->i2c_address +
271 				  control->ras_header_offset,
272 				  buf, RAS_TABLE_HEADER_SIZE);
273 	up_read(&adev->reset_domain->sem);
274 
275 	if (res < 0) {
276 		DRM_ERROR("Failed to write EEPROM table header:%d", res);
277 	} else if (res < RAS_TABLE_HEADER_SIZE) {
278 		DRM_ERROR("Short write:%d out of %d\n",
279 			  res, RAS_TABLE_HEADER_SIZE);
280 		res = -EIO;
281 	} else {
282 		res = 0;
283 	}
284 
285 	return res;
286 }
287 
288 static void
289 __encode_table_ras_info_to_buf(struct amdgpu_ras_eeprom_table_ras_info *rai,
290 			       unsigned char *buf)
291 {
292 	u32 *pp = (uint32_t *)buf;
293 	u32 tmp;
294 
295 	tmp = ((uint32_t)(rai->rma_status) & 0xFF) |
296 	      (((uint32_t)(rai->health_percent) << 8) & 0xFF00) |
297 	      (((uint32_t)(rai->ecc_page_threshold) << 16) & 0xFFFF0000);
298 	pp[0] = cpu_to_le32(tmp);
299 }
300 
301 static void
302 __decode_table_ras_info_from_buf(struct amdgpu_ras_eeprom_table_ras_info *rai,
303 				 unsigned char *buf)
304 {
305 	u32 *pp = (uint32_t *)buf;
306 	u32 tmp;
307 
308 	tmp = le32_to_cpu(pp[0]);
309 	rai->rma_status = tmp & 0xFF;
310 	rai->health_percent = (tmp >> 8) & 0xFF;
311 	rai->ecc_page_threshold = (tmp >> 16) & 0xFFFF;
312 }
313 
314 static int __write_table_ras_info(struct amdgpu_ras_eeprom_control *control)
315 {
316 	struct amdgpu_device *adev = to_amdgpu_device(control);
317 	u8 *buf;
318 	int res;
319 
320 	buf = kzalloc(RAS_TABLE_V2_1_INFO_SIZE, GFP_KERNEL);
321 	if (!buf) {
322 		DRM_ERROR("Failed to alloc buf to write table ras info\n");
323 		return -ENOMEM;
324 	}
325 
326 	__encode_table_ras_info_to_buf(&control->tbl_rai, buf);
327 
328 	/* i2c may be unstable in gpu reset */
329 	down_read(&adev->reset_domain->sem);
330 	res = amdgpu_eeprom_write(adev->pm.ras_eeprom_i2c_bus,
331 				  control->i2c_address +
332 				  control->ras_info_offset,
333 				  buf, RAS_TABLE_V2_1_INFO_SIZE);
334 	up_read(&adev->reset_domain->sem);
335 
336 	if (res < 0) {
337 		DRM_ERROR("Failed to write EEPROM table ras info:%d", res);
338 	} else if (res < RAS_TABLE_V2_1_INFO_SIZE) {
339 		DRM_ERROR("Short write:%d out of %d\n",
340 			  res, RAS_TABLE_V2_1_INFO_SIZE);
341 		res = -EIO;
342 	} else {
343 		res = 0;
344 	}
345 
346 	kfree(buf);
347 
348 	return res;
349 }
350 
351 static u8 __calc_hdr_byte_sum(const struct amdgpu_ras_eeprom_control *control)
352 {
353 	int ii;
354 	u8  *pp, csum;
355 	size_t sz;
356 
357 	/* Header checksum, skip checksum field in the calculation */
358 	sz = sizeof(control->tbl_hdr) - sizeof(control->tbl_hdr.checksum);
359 	pp = (u8 *) &control->tbl_hdr;
360 	csum = 0;
361 	for (ii = 0; ii < sz; ii++, pp++)
362 		csum += *pp;
363 
364 	return csum;
365 }
366 
367 static u8 __calc_ras_info_byte_sum(const struct amdgpu_ras_eeprom_control *control)
368 {
369 	int ii;
370 	u8  *pp, csum;
371 	size_t sz;
372 
373 	sz = sizeof(control->tbl_rai);
374 	pp = (u8 *) &control->tbl_rai;
375 	csum = 0;
376 	for (ii = 0; ii < sz; ii++, pp++)
377 		csum += *pp;
378 
379 	return csum;
380 }
381 
382 static int amdgpu_ras_eeprom_correct_header_tag(
383 	struct amdgpu_ras_eeprom_control *control,
384 	uint32_t header)
385 {
386 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
387 	u8 *hh;
388 	int res;
389 	u8 csum;
390 
391 	csum = -hdr->checksum;
392 
393 	hh = (void *) &hdr->header;
394 	csum -= (hh[0] + hh[1] + hh[2] + hh[3]);
395 	hh = (void *) &header;
396 	csum += hh[0] + hh[1] + hh[2] + hh[3];
397 	csum = -csum;
398 	mutex_lock(&control->ras_tbl_mutex);
399 	hdr->header = header;
400 	hdr->checksum = csum;
401 	res = __write_table_header(control);
402 	mutex_unlock(&control->ras_tbl_mutex);
403 
404 	return res;
405 }
406 
407 /**
408  * amdgpu_ras_eeprom_reset_table -- Reset the RAS EEPROM table
409  * @control: pointer to control structure
410  *
411  * Reset the contents of the header of the RAS EEPROM table.
412  * Return 0 on success, -errno on error.
413  */
414 int amdgpu_ras_eeprom_reset_table(struct amdgpu_ras_eeprom_control *control)
415 {
416 	struct amdgpu_device *adev = to_amdgpu_device(control);
417 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
418 	struct amdgpu_ras_eeprom_table_ras_info *rai = &control->tbl_rai;
419 	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
420 	u8 csum;
421 	int res;
422 
423 	mutex_lock(&control->ras_tbl_mutex);
424 
425 	hdr->header = RAS_TABLE_HDR_VAL;
426 	if (adev->umc.ras &&
427 	    adev->umc.ras->set_eeprom_table_version)
428 		adev->umc.ras->set_eeprom_table_version(hdr);
429 	else
430 		hdr->version = RAS_TABLE_VER_V1;
431 
432 	if (hdr->version == RAS_TABLE_VER_V2_1) {
433 		hdr->first_rec_offset = RAS_RECORD_START_V2_1;
434 		hdr->tbl_size = RAS_TABLE_HEADER_SIZE +
435 				RAS_TABLE_V2_1_INFO_SIZE;
436 		rai->rma_status = GPU_HEALTH_USABLE;
437 		/**
438 		 * GPU health represented as a percentage.
439 		 * 0 means worst health, 100 means fully health.
440 		 */
441 		rai->health_percent = 100;
442 		/* ecc_page_threshold = 0 means disable bad page retirement */
443 		rai->ecc_page_threshold = con->bad_page_cnt_threshold;
444 	} else {
445 		hdr->first_rec_offset = RAS_RECORD_START;
446 		hdr->tbl_size = RAS_TABLE_HEADER_SIZE;
447 	}
448 
449 	csum = __calc_hdr_byte_sum(control);
450 	if (hdr->version == RAS_TABLE_VER_V2_1)
451 		csum += __calc_ras_info_byte_sum(control);
452 	csum = -csum;
453 	hdr->checksum = csum;
454 	res = __write_table_header(control);
455 	if (!res && hdr->version > RAS_TABLE_VER_V1)
456 		res = __write_table_ras_info(control);
457 
458 	control->ras_num_recs = 0;
459 	control->ras_fri = 0;
460 
461 	amdgpu_dpm_send_hbm_bad_pages_num(adev, control->ras_num_recs);
462 
463 	control->bad_channel_bitmap = 0;
464 	amdgpu_dpm_send_hbm_bad_channel_flag(adev, control->bad_channel_bitmap);
465 	con->update_channel_flag = false;
466 
467 	amdgpu_ras_debugfs_set_ret_size(control);
468 
469 	mutex_unlock(&control->ras_tbl_mutex);
470 
471 	return res;
472 }
473 
474 static void
475 __encode_table_record_to_buf(struct amdgpu_ras_eeprom_control *control,
476 			     struct eeprom_table_record *record,
477 			     unsigned char *buf)
478 {
479 	__le64 tmp = 0;
480 	int i = 0;
481 
482 	/* Next are all record fields according to EEPROM page spec in LE foramt */
483 	buf[i++] = record->err_type;
484 
485 	buf[i++] = record->bank;
486 
487 	tmp = cpu_to_le64(record->ts);
488 	memcpy(buf + i, &tmp, 8);
489 	i += 8;
490 
491 	tmp = cpu_to_le64((record->offset & 0xffffffffffff));
492 	memcpy(buf + i, &tmp, 6);
493 	i += 6;
494 
495 	buf[i++] = record->mem_channel;
496 	buf[i++] = record->mcumc_id;
497 
498 	tmp = cpu_to_le64((record->retired_page & 0xffffffffffff));
499 	memcpy(buf + i, &tmp, 6);
500 }
501 
502 static void
503 __decode_table_record_from_buf(struct amdgpu_ras_eeprom_control *control,
504 			       struct eeprom_table_record *record,
505 			       unsigned char *buf)
506 {
507 	__le64 tmp = 0;
508 	int i =  0;
509 
510 	/* Next are all record fields according to EEPROM page spec in LE foramt */
511 	record->err_type = buf[i++];
512 
513 	record->bank = buf[i++];
514 
515 	memcpy(&tmp, buf + i, 8);
516 	record->ts = le64_to_cpu(tmp);
517 	i += 8;
518 
519 	memcpy(&tmp, buf + i, 6);
520 	record->offset = (le64_to_cpu(tmp) & 0xffffffffffff);
521 	i += 6;
522 
523 	record->mem_channel = buf[i++];
524 	record->mcumc_id = buf[i++];
525 
526 	memcpy(&tmp, buf + i,  6);
527 	record->retired_page = (le64_to_cpu(tmp) & 0xffffffffffff);
528 }
529 
530 bool amdgpu_ras_eeprom_check_err_threshold(struct amdgpu_device *adev)
531 {
532 	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
533 
534 	if (!__is_ras_eeprom_supported(adev) ||
535 	    !amdgpu_bad_page_threshold)
536 		return false;
537 
538 	/* skip check eeprom table for VEGA20 Gaming */
539 	if (!con)
540 		return false;
541 	else
542 		if (!(con->features & BIT(AMDGPU_RAS_BLOCK__UMC)))
543 			return false;
544 
545 	if (con->eeprom_control.tbl_hdr.header == RAS_TABLE_HDR_BAD) {
546 		if (amdgpu_bad_page_threshold == -1) {
547 			dev_warn(adev->dev, "RAS records:%d exceed threshold:%d",
548 				con->eeprom_control.ras_num_recs, con->bad_page_cnt_threshold);
549 			dev_warn(adev->dev,
550 				"But GPU can be operated due to bad_page_threshold = -1.\n");
551 			return false;
552 		} else {
553 			dev_warn(adev->dev, "This GPU is in BAD status.");
554 			dev_warn(adev->dev, "Please retire it or set a larger "
555 				 "threshold value when reloading driver.\n");
556 			return true;
557 		}
558 	}
559 
560 	return false;
561 }
562 
563 /**
564  * __amdgpu_ras_eeprom_write -- write indexed from buffer to EEPROM
565  * @control: pointer to control structure
566  * @buf: pointer to buffer containing data to write
567  * @fri: start writing at this index
568  * @num: number of records to write
569  *
570  * The caller must hold the table mutex in @control.
571  * Return 0 on success, -errno otherwise.
572  */
573 static int __amdgpu_ras_eeprom_write(struct amdgpu_ras_eeprom_control *control,
574 				     u8 *buf, const u32 fri, const u32 num)
575 {
576 	struct amdgpu_device *adev = to_amdgpu_device(control);
577 	u32 buf_size;
578 	int res;
579 
580 	/* i2c may be unstable in gpu reset */
581 	down_read(&adev->reset_domain->sem);
582 	buf_size = num * RAS_TABLE_RECORD_SIZE;
583 	res = amdgpu_eeprom_write(adev->pm.ras_eeprom_i2c_bus,
584 				  control->i2c_address +
585 				  RAS_INDEX_TO_OFFSET(control, fri),
586 				  buf, buf_size);
587 	up_read(&adev->reset_domain->sem);
588 	if (res < 0) {
589 		DRM_ERROR("Writing %d EEPROM table records error:%d",
590 			  num, res);
591 	} else if (res < buf_size) {
592 		/* Short write, return error.
593 		 */
594 		DRM_ERROR("Wrote %d records out of %d",
595 			  res / RAS_TABLE_RECORD_SIZE, num);
596 		res = -EIO;
597 	} else {
598 		res = 0;
599 	}
600 
601 	return res;
602 }
603 
604 static int
605 amdgpu_ras_eeprom_append_table(struct amdgpu_ras_eeprom_control *control,
606 			       struct eeprom_table_record *record,
607 			       const u32 num)
608 {
609 	struct amdgpu_ras *con = amdgpu_ras_get_context(to_amdgpu_device(control));
610 	u32 a, b, i;
611 	u8 *buf, *pp;
612 	int res;
613 
614 	buf = kcalloc(num, RAS_TABLE_RECORD_SIZE, GFP_KERNEL);
615 	if (!buf)
616 		return -ENOMEM;
617 
618 	/* Encode all of them in one go.
619 	 */
620 	pp = buf;
621 	for (i = 0; i < num; i++, pp += RAS_TABLE_RECORD_SIZE) {
622 		__encode_table_record_to_buf(control, &record[i], pp);
623 
624 		/* update bad channel bitmap */
625 		if ((record[i].mem_channel < BITS_PER_TYPE(control->bad_channel_bitmap)) &&
626 		    !(control->bad_channel_bitmap & (1 << record[i].mem_channel))) {
627 			control->bad_channel_bitmap |= 1 << record[i].mem_channel;
628 			con->update_channel_flag = true;
629 		}
630 	}
631 
632 	/* a, first record index to write into.
633 	 * b, last record index to write into.
634 	 * a = first index to read (fri) + number of records in the table,
635 	 * b = a + @num - 1.
636 	 * Let N = control->ras_max_num_record_count, then we have,
637 	 * case 0: 0 <= a <= b < N,
638 	 *   just append @num records starting at a;
639 	 * case 1: 0 <= a < N <= b,
640 	 *   append (N - a) records starting at a, and
641 	 *   append the remainder,  b % N + 1, starting at 0.
642 	 * case 2: 0 <= fri < N <= a <= b, then modulo N we get two subcases,
643 	 * case 2a: 0 <= a <= b < N
644 	 *   append num records starting at a; and fix fri if b overwrote it,
645 	 *   and since a <= b, if b overwrote it then a must've also,
646 	 *   and if b didn't overwrite it, then a didn't also.
647 	 * case 2b: 0 <= b < a < N
648 	 *   write num records starting at a, which wraps around 0=N
649 	 *   and overwrite fri unconditionally. Now from case 2a,
650 	 *   this means that b eclipsed fri to overwrite it and wrap
651 	 *   around 0 again, i.e. b = 2N+r pre modulo N, so we unconditionally
652 	 *   set fri = b + 1 (mod N).
653 	 * Now, since fri is updated in every case, except the trivial case 0,
654 	 * the number of records present in the table after writing, is,
655 	 * num_recs - 1 = b - fri (mod N), and we take the positive value,
656 	 * by adding an arbitrary multiple of N before taking the modulo N
657 	 * as shown below.
658 	 */
659 	a = control->ras_fri + control->ras_num_recs;
660 	b = a + num  - 1;
661 	if (b < control->ras_max_record_count) {
662 		res = __amdgpu_ras_eeprom_write(control, buf, a, num);
663 	} else if (a < control->ras_max_record_count) {
664 		u32 g0, g1;
665 
666 		g0 = control->ras_max_record_count - a;
667 		g1 = b % control->ras_max_record_count + 1;
668 		res = __amdgpu_ras_eeprom_write(control, buf, a, g0);
669 		if (res)
670 			goto Out;
671 		res = __amdgpu_ras_eeprom_write(control,
672 						buf + g0 * RAS_TABLE_RECORD_SIZE,
673 						0, g1);
674 		if (res)
675 			goto Out;
676 		if (g1 > control->ras_fri)
677 			control->ras_fri = g1 % control->ras_max_record_count;
678 	} else {
679 		a %= control->ras_max_record_count;
680 		b %= control->ras_max_record_count;
681 
682 		if (a <= b) {
683 			/* Note that, b - a + 1 = num. */
684 			res = __amdgpu_ras_eeprom_write(control, buf, a, num);
685 			if (res)
686 				goto Out;
687 			if (b >= control->ras_fri)
688 				control->ras_fri = (b + 1) % control->ras_max_record_count;
689 		} else {
690 			u32 g0, g1;
691 
692 			/* b < a, which means, we write from
693 			 * a to the end of the table, and from
694 			 * the start of the table to b.
695 			 */
696 			g0 = control->ras_max_record_count - a;
697 			g1 = b + 1;
698 			res = __amdgpu_ras_eeprom_write(control, buf, a, g0);
699 			if (res)
700 				goto Out;
701 			res = __amdgpu_ras_eeprom_write(control,
702 							buf + g0 * RAS_TABLE_RECORD_SIZE,
703 							0, g1);
704 			if (res)
705 				goto Out;
706 			control->ras_fri = g1 % control->ras_max_record_count;
707 		}
708 	}
709 	control->ras_num_recs = 1 + (control->ras_max_record_count + b
710 				     - control->ras_fri)
711 		% control->ras_max_record_count;
712 Out:
713 	kfree(buf);
714 	return res;
715 }
716 
717 static int
718 amdgpu_ras_eeprom_update_header(struct amdgpu_ras_eeprom_control *control)
719 {
720 	struct amdgpu_device *adev = to_amdgpu_device(control);
721 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
722 	u8 *buf, *pp, csum;
723 	u32 buf_size;
724 	int res;
725 
726 	/* Modify the header if it exceeds.
727 	 */
728 	if (amdgpu_bad_page_threshold != 0 &&
729 	    control->ras_num_recs >= ras->bad_page_cnt_threshold) {
730 		dev_warn(adev->dev,
731 			"Saved bad pages %d reaches threshold value %d\n",
732 			control->ras_num_recs, ras->bad_page_cnt_threshold);
733 		control->tbl_hdr.header = RAS_TABLE_HDR_BAD;
734 		if (control->tbl_hdr.version == RAS_TABLE_VER_V2_1) {
735 			control->tbl_rai.rma_status = GPU_RETIRED__ECC_REACH_THRESHOLD;
736 			control->tbl_rai.health_percent = 0;
737 		}
738 	}
739 
740 	if (control->tbl_hdr.version == RAS_TABLE_VER_V2_1)
741 		control->tbl_hdr.tbl_size = RAS_TABLE_HEADER_SIZE +
742 					    RAS_TABLE_V2_1_INFO_SIZE +
743 					    control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
744 	else
745 		control->tbl_hdr.tbl_size = RAS_TABLE_HEADER_SIZE +
746 					    control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
747 	control->tbl_hdr.checksum = 0;
748 
749 	buf_size = control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
750 	buf = kcalloc(control->ras_num_recs, RAS_TABLE_RECORD_SIZE, GFP_KERNEL);
751 	if (!buf) {
752 		DRM_ERROR("allocating memory for table of size %d bytes failed\n",
753 			  control->tbl_hdr.tbl_size);
754 		res = -ENOMEM;
755 		goto Out;
756 	}
757 
758 	down_read(&adev->reset_domain->sem);
759 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
760 				 control->i2c_address +
761 				 control->ras_record_offset,
762 				 buf, buf_size);
763 	up_read(&adev->reset_domain->sem);
764 	if (res < 0) {
765 		DRM_ERROR("EEPROM failed reading records:%d\n",
766 			  res);
767 		goto Out;
768 	} else if (res < buf_size) {
769 		DRM_ERROR("EEPROM read %d out of %d bytes\n",
770 			  res, buf_size);
771 		res = -EIO;
772 		goto Out;
773 	}
774 
775 	/**
776 	 * bad page records have been stored in eeprom,
777 	 * now calculate gpu health percent
778 	 */
779 	if (amdgpu_bad_page_threshold != 0 &&
780 	    control->tbl_hdr.version == RAS_TABLE_VER_V2_1 &&
781 	    control->ras_num_recs < ras->bad_page_cnt_threshold)
782 		control->tbl_rai.health_percent = ((ras->bad_page_cnt_threshold -
783 						   control->ras_num_recs) * 100) /
784 						   ras->bad_page_cnt_threshold;
785 
786 	/* Recalc the checksum.
787 	 */
788 	csum = 0;
789 	for (pp = buf; pp < buf + buf_size; pp++)
790 		csum += *pp;
791 
792 	csum += __calc_hdr_byte_sum(control);
793 	if (control->tbl_hdr.version == RAS_TABLE_VER_V2_1)
794 		csum += __calc_ras_info_byte_sum(control);
795 	/* avoid sign extension when assigning to "checksum" */
796 	csum = -csum;
797 	control->tbl_hdr.checksum = csum;
798 	res = __write_table_header(control);
799 	if (!res && control->tbl_hdr.version > RAS_TABLE_VER_V1)
800 		res = __write_table_ras_info(control);
801 Out:
802 	kfree(buf);
803 	return res;
804 }
805 
806 /**
807  * amdgpu_ras_eeprom_append -- append records to the EEPROM RAS table
808  * @control: pointer to control structure
809  * @record: array of records to append
810  * @num: number of records in @record array
811  *
812  * Append @num records to the table, calculate the checksum and write
813  * the table back to EEPROM. The maximum number of records that
814  * can be appended is between 1 and control->ras_max_record_count,
815  * regardless of how many records are already stored in the table.
816  *
817  * Return 0 on success or if EEPROM is not supported, -errno on error.
818  */
819 int amdgpu_ras_eeprom_append(struct amdgpu_ras_eeprom_control *control,
820 			     struct eeprom_table_record *record,
821 			     const u32 num)
822 {
823 	struct amdgpu_device *adev = to_amdgpu_device(control);
824 	int res;
825 
826 	if (!__is_ras_eeprom_supported(adev))
827 		return 0;
828 
829 	if (num == 0) {
830 		DRM_ERROR("will not append 0 records\n");
831 		return -EINVAL;
832 	} else if (num > control->ras_max_record_count) {
833 		DRM_ERROR("cannot append %d records than the size of table %d\n",
834 			  num, control->ras_max_record_count);
835 		return -EINVAL;
836 	}
837 
838 	mutex_lock(&control->ras_tbl_mutex);
839 
840 	res = amdgpu_ras_eeprom_append_table(control, record, num);
841 	if (!res)
842 		res = amdgpu_ras_eeprom_update_header(control);
843 	if (!res)
844 		amdgpu_ras_debugfs_set_ret_size(control);
845 
846 	mutex_unlock(&control->ras_tbl_mutex);
847 	return res;
848 }
849 
850 /**
851  * __amdgpu_ras_eeprom_read -- read indexed from EEPROM into buffer
852  * @control: pointer to control structure
853  * @buf: pointer to buffer to read into
854  * @fri: first record index, start reading at this index, absolute index
855  * @num: number of records to read
856  *
857  * The caller must hold the table mutex in @control.
858  * Return 0 on success, -errno otherwise.
859  */
860 static int __amdgpu_ras_eeprom_read(struct amdgpu_ras_eeprom_control *control,
861 				    u8 *buf, const u32 fri, const u32 num)
862 {
863 	struct amdgpu_device *adev = to_amdgpu_device(control);
864 	u32 buf_size;
865 	int res;
866 
867 	/* i2c may be unstable in gpu reset */
868 	down_read(&adev->reset_domain->sem);
869 	buf_size = num * RAS_TABLE_RECORD_SIZE;
870 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
871 				 control->i2c_address +
872 				 RAS_INDEX_TO_OFFSET(control, fri),
873 				 buf, buf_size);
874 	up_read(&adev->reset_domain->sem);
875 	if (res < 0) {
876 		DRM_ERROR("Reading %d EEPROM table records error:%d",
877 			  num, res);
878 	} else if (res < buf_size) {
879 		/* Short read, return error.
880 		 */
881 		DRM_ERROR("Read %d records out of %d",
882 			  res / RAS_TABLE_RECORD_SIZE, num);
883 		res = -EIO;
884 	} else {
885 		res = 0;
886 	}
887 
888 	return res;
889 }
890 
891 /**
892  * amdgpu_ras_eeprom_read -- read EEPROM
893  * @control: pointer to control structure
894  * @record: array of records to read into
895  * @num: number of records in @record
896  *
897  * Reads num records from the RAS table in EEPROM and
898  * writes the data into @record array.
899  *
900  * Returns 0 on success, -errno on error.
901  */
902 int amdgpu_ras_eeprom_read(struct amdgpu_ras_eeprom_control *control,
903 			   struct eeprom_table_record *record,
904 			   const u32 num)
905 {
906 	struct amdgpu_device *adev = to_amdgpu_device(control);
907 	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
908 	int i, res;
909 	u8 *buf, *pp;
910 	u32 g0, g1;
911 
912 	if (!__is_ras_eeprom_supported(adev))
913 		return 0;
914 
915 	if (num == 0) {
916 		DRM_ERROR("will not read 0 records\n");
917 		return -EINVAL;
918 	} else if (num > control->ras_num_recs) {
919 		DRM_ERROR("too many records to read:%d available:%d\n",
920 			  num, control->ras_num_recs);
921 		return -EINVAL;
922 	}
923 
924 	buf = kcalloc(num, RAS_TABLE_RECORD_SIZE, GFP_KERNEL);
925 	if (!buf)
926 		return -ENOMEM;
927 
928 	/* Determine how many records to read, from the first record
929 	 * index, fri, to the end of the table, and from the beginning
930 	 * of the table, such that the total number of records is
931 	 * @num, and we handle wrap around when fri > 0 and
932 	 * fri + num > RAS_MAX_RECORD_COUNT.
933 	 *
934 	 * First we compute the index of the last element
935 	 * which would be fetched from each region,
936 	 * g0 is in [fri, fri + num - 1], and
937 	 * g1 is in [0, RAS_MAX_RECORD_COUNT - 1].
938 	 * Then, if g0 < RAS_MAX_RECORD_COUNT, the index of
939 	 * the last element to fetch, we set g0 to _the number_
940 	 * of elements to fetch, @num, since we know that the last
941 	 * indexed to be fetched does not exceed the table.
942 	 *
943 	 * If, however, g0 >= RAS_MAX_RECORD_COUNT, then
944 	 * we set g0 to the number of elements to read
945 	 * until the end of the table, and g1 to the number of
946 	 * elements to read from the beginning of the table.
947 	 */
948 	g0 = control->ras_fri + num - 1;
949 	g1 = g0 % control->ras_max_record_count;
950 	if (g0 < control->ras_max_record_count) {
951 		g0 = num;
952 		g1 = 0;
953 	} else {
954 		g0 = control->ras_max_record_count - control->ras_fri;
955 		g1 += 1;
956 	}
957 
958 	mutex_lock(&control->ras_tbl_mutex);
959 	res = __amdgpu_ras_eeprom_read(control, buf, control->ras_fri, g0);
960 	if (res)
961 		goto Out;
962 	if (g1) {
963 		res = __amdgpu_ras_eeprom_read(control,
964 					       buf + g0 * RAS_TABLE_RECORD_SIZE,
965 					       0, g1);
966 		if (res)
967 			goto Out;
968 	}
969 
970 	res = 0;
971 
972 	/* Read up everything? Then transform.
973 	 */
974 	pp = buf;
975 	for (i = 0; i < num; i++, pp += RAS_TABLE_RECORD_SIZE) {
976 		__decode_table_record_from_buf(control, &record[i], pp);
977 
978 		/* update bad channel bitmap */
979 		if ((record[i].mem_channel < BITS_PER_TYPE(control->bad_channel_bitmap)) &&
980 		    !(control->bad_channel_bitmap & (1 << record[i].mem_channel))) {
981 			control->bad_channel_bitmap |= 1 << record[i].mem_channel;
982 			con->update_channel_flag = true;
983 		}
984 	}
985 Out:
986 	kfree(buf);
987 	mutex_unlock(&control->ras_tbl_mutex);
988 
989 	return res;
990 }
991 
992 uint32_t amdgpu_ras_eeprom_max_record_count(struct amdgpu_ras_eeprom_control *control)
993 {
994 	if (control->tbl_hdr.version == RAS_TABLE_VER_V2_1)
995 		return RAS_MAX_RECORD_COUNT_V2_1;
996 	else
997 		return RAS_MAX_RECORD_COUNT;
998 }
999 
1000 static ssize_t
1001 amdgpu_ras_debugfs_eeprom_size_read(struct file *f, char __user *buf,
1002 				    size_t size, loff_t *pos)
1003 {
1004 	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
1005 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
1006 	struct amdgpu_ras_eeprom_control *control = ras ? &ras->eeprom_control : NULL;
1007 	u8 data[50];
1008 	int res;
1009 
1010 	if (!size)
1011 		return size;
1012 
1013 	if (!ras || !control) {
1014 		res = snprintf(data, sizeof(data), "Not supported\n");
1015 	} else {
1016 		res = snprintf(data, sizeof(data), "%d bytes or %d records\n",
1017 			       RAS_TBL_SIZE_BYTES, control->ras_max_record_count);
1018 	}
1019 
1020 	if (*pos >= res)
1021 		return 0;
1022 
1023 	res -= *pos;
1024 	res = min_t(size_t, res, size);
1025 
1026 	if (copy_to_user(buf, &data[*pos], res))
1027 		return -EFAULT;
1028 
1029 	*pos += res;
1030 
1031 	return res;
1032 }
1033 
1034 const struct file_operations amdgpu_ras_debugfs_eeprom_size_ops = {
1035 	.owner = THIS_MODULE,
1036 	.read = amdgpu_ras_debugfs_eeprom_size_read,
1037 	.write = NULL,
1038 	.llseek = default_llseek,
1039 };
1040 
1041 static const char *tbl_hdr_str = " Signature    Version  FirstOffs       Size   Checksum\n";
1042 static const char *tbl_hdr_fmt = "0x%08X 0x%08X 0x%08X 0x%08X 0x%08X\n";
1043 #define tbl_hdr_fmt_size (5 * (2+8) + 4 + 1)
1044 static const char *rec_hdr_str = "Index  Offset ErrType Bank/CU          TimeStamp      Offs/Addr MemChl MCUMCID    RetiredPage\n";
1045 static const char *rec_hdr_fmt = "%5d 0x%05X %7s    0x%02X 0x%016llX 0x%012llX   0x%02X    0x%02X 0x%012llX\n";
1046 #define rec_hdr_fmt_size (5 + 1 + 7 + 1 + 7 + 1 + 7 + 1 + 18 + 1 + 14 + 1 + 6 + 1 + 7 + 1 + 14 + 1)
1047 
1048 static const char *record_err_type_str[AMDGPU_RAS_EEPROM_ERR_COUNT] = {
1049 	"ignore",
1050 	"re",
1051 	"ue",
1052 };
1053 
1054 static loff_t amdgpu_ras_debugfs_table_size(struct amdgpu_ras_eeprom_control *control)
1055 {
1056 	return strlen(tbl_hdr_str) + tbl_hdr_fmt_size +
1057 		strlen(rec_hdr_str) + rec_hdr_fmt_size * control->ras_num_recs;
1058 }
1059 
1060 void amdgpu_ras_debugfs_set_ret_size(struct amdgpu_ras_eeprom_control *control)
1061 {
1062 	struct amdgpu_ras *ras = container_of(control, struct amdgpu_ras,
1063 					      eeprom_control);
1064 	struct dentry *de = ras->de_ras_eeprom_table;
1065 
1066 	if (de)
1067 		d_inode(de)->i_size = amdgpu_ras_debugfs_table_size(control);
1068 }
1069 
1070 static ssize_t amdgpu_ras_debugfs_table_read(struct file *f, char __user *buf,
1071 					     size_t size, loff_t *pos)
1072 {
1073 	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
1074 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
1075 	struct amdgpu_ras_eeprom_control *control = &ras->eeprom_control;
1076 	const size_t orig_size = size;
1077 	int res = -EFAULT;
1078 	size_t data_len;
1079 
1080 	mutex_lock(&control->ras_tbl_mutex);
1081 
1082 	/* We want *pos - data_len > 0, which means there's
1083 	 * bytes to be printed from data.
1084 	 */
1085 	data_len = strlen(tbl_hdr_str);
1086 	if (*pos < data_len) {
1087 		data_len -= *pos;
1088 		data_len = min_t(size_t, data_len, size);
1089 		if (copy_to_user(buf, &tbl_hdr_str[*pos], data_len))
1090 			goto Out;
1091 		buf += data_len;
1092 		size -= data_len;
1093 		*pos += data_len;
1094 	}
1095 
1096 	data_len = strlen(tbl_hdr_str) + tbl_hdr_fmt_size;
1097 	if (*pos < data_len && size > 0) {
1098 		u8 data[tbl_hdr_fmt_size + 1];
1099 		loff_t lpos;
1100 
1101 		snprintf(data, sizeof(data), tbl_hdr_fmt,
1102 			 control->tbl_hdr.header,
1103 			 control->tbl_hdr.version,
1104 			 control->tbl_hdr.first_rec_offset,
1105 			 control->tbl_hdr.tbl_size,
1106 			 control->tbl_hdr.checksum);
1107 
1108 		data_len -= *pos;
1109 		data_len = min_t(size_t, data_len, size);
1110 		lpos = *pos - strlen(tbl_hdr_str);
1111 		if (copy_to_user(buf, &data[lpos], data_len))
1112 			goto Out;
1113 		buf += data_len;
1114 		size -= data_len;
1115 		*pos += data_len;
1116 	}
1117 
1118 	data_len = strlen(tbl_hdr_str) + tbl_hdr_fmt_size + strlen(rec_hdr_str);
1119 	if (*pos < data_len && size > 0) {
1120 		loff_t lpos;
1121 
1122 		data_len -= *pos;
1123 		data_len = min_t(size_t, data_len, size);
1124 		lpos = *pos - strlen(tbl_hdr_str) - tbl_hdr_fmt_size;
1125 		if (copy_to_user(buf, &rec_hdr_str[lpos], data_len))
1126 			goto Out;
1127 		buf += data_len;
1128 		size -= data_len;
1129 		*pos += data_len;
1130 	}
1131 
1132 	data_len = amdgpu_ras_debugfs_table_size(control);
1133 	if (*pos < data_len && size > 0) {
1134 		u8 dare[RAS_TABLE_RECORD_SIZE];
1135 		u8 data[rec_hdr_fmt_size + 1];
1136 		struct eeprom_table_record record;
1137 		int s, r;
1138 
1139 		/* Find the starting record index
1140 		 */
1141 		s = *pos - strlen(tbl_hdr_str) - tbl_hdr_fmt_size -
1142 			strlen(rec_hdr_str);
1143 		s = s / rec_hdr_fmt_size;
1144 		r = *pos - strlen(tbl_hdr_str) - tbl_hdr_fmt_size -
1145 			strlen(rec_hdr_str);
1146 		r = r % rec_hdr_fmt_size;
1147 
1148 		for ( ; size > 0 && s < control->ras_num_recs; s++) {
1149 			u32 ai = RAS_RI_TO_AI(control, s);
1150 			/* Read a single record
1151 			 */
1152 			res = __amdgpu_ras_eeprom_read(control, dare, ai, 1);
1153 			if (res)
1154 				goto Out;
1155 			__decode_table_record_from_buf(control, &record, dare);
1156 			snprintf(data, sizeof(data), rec_hdr_fmt,
1157 				 s,
1158 				 RAS_INDEX_TO_OFFSET(control, ai),
1159 				 record_err_type_str[record.err_type],
1160 				 record.bank,
1161 				 record.ts,
1162 				 record.offset,
1163 				 record.mem_channel,
1164 				 record.mcumc_id,
1165 				 record.retired_page);
1166 
1167 			data_len = min_t(size_t, rec_hdr_fmt_size - r, size);
1168 			if (copy_to_user(buf, &data[r], data_len)) {
1169 				res = -EFAULT;
1170 				goto Out;
1171 			}
1172 			buf += data_len;
1173 			size -= data_len;
1174 			*pos += data_len;
1175 			r = 0;
1176 		}
1177 	}
1178 	res = 0;
1179 Out:
1180 	mutex_unlock(&control->ras_tbl_mutex);
1181 	return res < 0 ? res : orig_size - size;
1182 }
1183 
1184 static ssize_t
1185 amdgpu_ras_debugfs_eeprom_table_read(struct file *f, char __user *buf,
1186 				     size_t size, loff_t *pos)
1187 {
1188 	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
1189 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
1190 	struct amdgpu_ras_eeprom_control *control = ras ? &ras->eeprom_control : NULL;
1191 	u8 data[81];
1192 	int res;
1193 
1194 	if (!size)
1195 		return size;
1196 
1197 	if (!ras || !control) {
1198 		res = snprintf(data, sizeof(data), "Not supported\n");
1199 		if (*pos >= res)
1200 			return 0;
1201 
1202 		res -= *pos;
1203 		res = min_t(size_t, res, size);
1204 
1205 		if (copy_to_user(buf, &data[*pos], res))
1206 			return -EFAULT;
1207 
1208 		*pos += res;
1209 
1210 		return res;
1211 	} else {
1212 		return amdgpu_ras_debugfs_table_read(f, buf, size, pos);
1213 	}
1214 }
1215 
1216 const struct file_operations amdgpu_ras_debugfs_eeprom_table_ops = {
1217 	.owner = THIS_MODULE,
1218 	.read = amdgpu_ras_debugfs_eeprom_table_read,
1219 	.write = NULL,
1220 	.llseek = default_llseek,
1221 };
1222 
1223 /**
1224  * __verify_ras_table_checksum -- verify the RAS EEPROM table checksum
1225  * @control: pointer to control structure
1226  *
1227  * Check the checksum of the stored in EEPROM RAS table.
1228  *
1229  * Return 0 if the checksum is correct,
1230  * positive if it is not correct, and
1231  * -errno on I/O error.
1232  */
1233 static int __verify_ras_table_checksum(struct amdgpu_ras_eeprom_control *control)
1234 {
1235 	struct amdgpu_device *adev = to_amdgpu_device(control);
1236 	int buf_size, res;
1237 	u8  csum, *buf, *pp;
1238 
1239 	if (control->tbl_hdr.version == RAS_TABLE_VER_V2_1)
1240 		buf_size = RAS_TABLE_HEADER_SIZE +
1241 			   RAS_TABLE_V2_1_INFO_SIZE +
1242 			   control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
1243 	else
1244 		buf_size = RAS_TABLE_HEADER_SIZE +
1245 			   control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
1246 
1247 	buf = kzalloc(buf_size, GFP_KERNEL);
1248 	if (!buf) {
1249 		DRM_ERROR("Out of memory checking RAS table checksum.\n");
1250 		return -ENOMEM;
1251 	}
1252 
1253 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
1254 				 control->i2c_address +
1255 				 control->ras_header_offset,
1256 				 buf, buf_size);
1257 	if (res < buf_size) {
1258 		DRM_ERROR("Partial read for checksum, res:%d\n", res);
1259 		/* On partial reads, return -EIO.
1260 		 */
1261 		if (res >= 0)
1262 			res = -EIO;
1263 		goto Out;
1264 	}
1265 
1266 	csum = 0;
1267 	for (pp = buf; pp < buf + buf_size; pp++)
1268 		csum += *pp;
1269 Out:
1270 	kfree(buf);
1271 	return res < 0 ? res : csum;
1272 }
1273 
1274 static int __read_table_ras_info(struct amdgpu_ras_eeprom_control *control)
1275 {
1276 	struct amdgpu_ras_eeprom_table_ras_info *rai = &control->tbl_rai;
1277 	struct amdgpu_device *adev = to_amdgpu_device(control);
1278 	unsigned char *buf;
1279 	int res;
1280 
1281 	buf = kzalloc(RAS_TABLE_V2_1_INFO_SIZE, GFP_KERNEL);
1282 	if (!buf) {
1283 		DRM_ERROR("Failed to alloc buf to read EEPROM table ras info\n");
1284 		return -ENOMEM;
1285 	}
1286 
1287 	/**
1288 	 * EEPROM table V2_1 supports ras info,
1289 	 * read EEPROM table ras info
1290 	 */
1291 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
1292 				 control->i2c_address + control->ras_info_offset,
1293 				 buf, RAS_TABLE_V2_1_INFO_SIZE);
1294 	if (res < RAS_TABLE_V2_1_INFO_SIZE) {
1295 		DRM_ERROR("Failed to read EEPROM table ras info, res:%d", res);
1296 		res = res >= 0 ? -EIO : res;
1297 		goto Out;
1298 	}
1299 
1300 	__decode_table_ras_info_from_buf(rai, buf);
1301 
1302 Out:
1303 	kfree(buf);
1304 	return res == RAS_TABLE_V2_1_INFO_SIZE ? 0 : res;
1305 }
1306 
1307 int amdgpu_ras_eeprom_init(struct amdgpu_ras_eeprom_control *control,
1308 			   bool *exceed_err_limit)
1309 {
1310 	struct amdgpu_device *adev = to_amdgpu_device(control);
1311 	unsigned char buf[RAS_TABLE_HEADER_SIZE] = { 0 };
1312 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
1313 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
1314 	int res;
1315 
1316 	*exceed_err_limit = false;
1317 
1318 	if (!__is_ras_eeprom_supported(adev))
1319 		return 0;
1320 
1321 	/* Verify i2c adapter is initialized */
1322 	if (!adev->pm.ras_eeprom_i2c_bus || !adev->pm.ras_eeprom_i2c_bus->algo)
1323 		return -ENOENT;
1324 
1325 	if (!__get_eeprom_i2c_addr(adev, control))
1326 		return -EINVAL;
1327 
1328 	control->ras_header_offset = RAS_HDR_START;
1329 	control->ras_info_offset = RAS_TABLE_V2_1_INFO_START;
1330 	mutex_init(&control->ras_tbl_mutex);
1331 
1332 	/* Read the table header from EEPROM address */
1333 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
1334 				 control->i2c_address + control->ras_header_offset,
1335 				 buf, RAS_TABLE_HEADER_SIZE);
1336 	if (res < RAS_TABLE_HEADER_SIZE) {
1337 		DRM_ERROR("Failed to read EEPROM table header, res:%d", res);
1338 		return res >= 0 ? -EIO : res;
1339 	}
1340 
1341 	__decode_table_header_from_buf(hdr, buf);
1342 
1343 	if (hdr->version == RAS_TABLE_VER_V2_1) {
1344 		control->ras_num_recs = RAS_NUM_RECS_V2_1(hdr);
1345 		control->ras_record_offset = RAS_RECORD_START_V2_1;
1346 		control->ras_max_record_count = RAS_MAX_RECORD_COUNT_V2_1;
1347 	} else {
1348 		control->ras_num_recs = RAS_NUM_RECS(hdr);
1349 		control->ras_record_offset = RAS_RECORD_START;
1350 		control->ras_max_record_count = RAS_MAX_RECORD_COUNT;
1351 	}
1352 	control->ras_fri = RAS_OFFSET_TO_INDEX(control, hdr->first_rec_offset);
1353 
1354 	if (hdr->header == RAS_TABLE_HDR_VAL) {
1355 		DRM_DEBUG_DRIVER("Found existing EEPROM table with %d records",
1356 				 control->ras_num_recs);
1357 
1358 		if (hdr->version == RAS_TABLE_VER_V2_1) {
1359 			res = __read_table_ras_info(control);
1360 			if (res)
1361 				return res;
1362 		}
1363 
1364 		res = __verify_ras_table_checksum(control);
1365 		if (res)
1366 			DRM_ERROR("RAS table incorrect checksum or error:%d\n",
1367 				  res);
1368 
1369 		/* Warn if we are at 90% of the threshold or above
1370 		 */
1371 		if (10 * control->ras_num_recs >= 9 * ras->bad_page_cnt_threshold)
1372 			dev_warn(adev->dev, "RAS records:%u exceeds 90%% of threshold:%d",
1373 					control->ras_num_recs,
1374 					ras->bad_page_cnt_threshold);
1375 	} else if (hdr->header == RAS_TABLE_HDR_BAD &&
1376 		   amdgpu_bad_page_threshold != 0) {
1377 		if (hdr->version == RAS_TABLE_VER_V2_1) {
1378 			res = __read_table_ras_info(control);
1379 			if (res)
1380 				return res;
1381 		}
1382 
1383 		res = __verify_ras_table_checksum(control);
1384 		if (res)
1385 			DRM_ERROR("RAS Table incorrect checksum or error:%d\n",
1386 				  res);
1387 		if (ras->bad_page_cnt_threshold > control->ras_num_recs) {
1388 			/* This means that, the threshold was increased since
1389 			 * the last time the system was booted, and now,
1390 			 * ras->bad_page_cnt_threshold - control->num_recs > 0,
1391 			 * so that at least one more record can be saved,
1392 			 * before the page count threshold is reached.
1393 			 */
1394 			dev_info(adev->dev,
1395 				 "records:%d threshold:%d, resetting "
1396 				 "RAS table header signature",
1397 				 control->ras_num_recs,
1398 				 ras->bad_page_cnt_threshold);
1399 			res = amdgpu_ras_eeprom_correct_header_tag(control,
1400 								   RAS_TABLE_HDR_VAL);
1401 		} else {
1402 			dev_err(adev->dev, "RAS records:%d exceed threshold:%d",
1403 				control->ras_num_recs, ras->bad_page_cnt_threshold);
1404 			if (amdgpu_bad_page_threshold == -1) {
1405 				dev_warn(adev->dev, "GPU will be initialized due to bad_page_threshold = -1.");
1406 				res = 0;
1407 			} else {
1408 				*exceed_err_limit = true;
1409 				dev_err(adev->dev,
1410 					"RAS records:%d exceed threshold:%d, "
1411 					"GPU will not be initialized. Replace this GPU or increase the threshold",
1412 					control->ras_num_recs, ras->bad_page_cnt_threshold);
1413 			}
1414 		}
1415 	} else {
1416 		DRM_INFO("Creating a new EEPROM table");
1417 
1418 		res = amdgpu_ras_eeprom_reset_table(control);
1419 	}
1420 
1421 	return res < 0 ? res : 0;
1422 }
1423