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 #define EEPROM_I2C_MADDR_VEGA20         0x0
37 #define EEPROM_I2C_MADDR_ARCTURUS       0x40000
38 #define EEPROM_I2C_MADDR_ARCTURUS_D342  0x0
39 #define EEPROM_I2C_MADDR_SIENNA_CICHLID 0x0
40 #define EEPROM_I2C_MADDR_ALDEBARAN      0x0
41 
42 /*
43  * The 2 macros bellow represent the actual size in bytes that
44  * those entities occupy in the EEPROM memory.
45  * RAS_TABLE_RECORD_SIZE is different than sizeof(eeprom_table_record) which
46  * uses uint64 to store 6b fields such as retired_page.
47  */
48 #define RAS_TABLE_HEADER_SIZE   20
49 #define RAS_TABLE_RECORD_SIZE   24
50 
51 /* Table hdr is 'AMDR' */
52 #define RAS_TABLE_HDR_VAL       0x414d4452
53 #define RAS_TABLE_VER           0x00010000
54 
55 /* Bad GPU tag ‘BADG’ */
56 #define RAS_TABLE_HDR_BAD       0x42414447
57 
58 /* Assume 2-Mbit size EEPROM and take up the whole space. */
59 #define RAS_TBL_SIZE_BYTES      (256 * 1024)
60 #define RAS_TABLE_START         0
61 #define RAS_HDR_START           RAS_TABLE_START
62 #define RAS_RECORD_START        (RAS_HDR_START + RAS_TABLE_HEADER_SIZE)
63 #define RAS_MAX_RECORD_COUNT    ((RAS_TBL_SIZE_BYTES - RAS_TABLE_HEADER_SIZE) \
64 				 / RAS_TABLE_RECORD_SIZE)
65 
66 /* Given a zero-based index of an EEPROM RAS record, yields the EEPROM
67  * offset off of RAS_TABLE_START.  That is, this is something you can
68  * add to control->i2c_address, and then tell I2C layer to read
69  * from/write to there. _N is the so called absolute index,
70  * because it starts right after the table header.
71  */
72 #define RAS_INDEX_TO_OFFSET(_C, _N) ((_C)->ras_record_offset + \
73 				     (_N) * RAS_TABLE_RECORD_SIZE)
74 
75 #define RAS_OFFSET_TO_INDEX(_C, _O) (((_O) - \
76 				      (_C)->ras_record_offset) / RAS_TABLE_RECORD_SIZE)
77 
78 /* Given a 0-based relative record index, 0, 1, 2, ..., etc., off
79  * of "fri", return the absolute record index off of the end of
80  * the table header.
81  */
82 #define RAS_RI_TO_AI(_C, _I) (((_I) + (_C)->ras_fri) % \
83 			      (_C)->ras_max_record_count)
84 
85 #define RAS_NUM_RECS(_tbl_hdr)  (((_tbl_hdr)->tbl_size - \
86 				  RAS_TABLE_HEADER_SIZE) / RAS_TABLE_RECORD_SIZE)
87 
88 #define to_amdgpu_device(x) (container_of(x, struct amdgpu_ras, eeprom_control))->adev
89 
90 static bool __is_ras_eeprom_supported(struct amdgpu_device *adev)
91 {
92 	return  adev->asic_type == CHIP_VEGA20 ||
93 		adev->asic_type == CHIP_ARCTURUS ||
94 		adev->asic_type == CHIP_SIENNA_CICHLID ||
95 		adev->asic_type == CHIP_ALDEBARAN;
96 }
97 
98 static bool __get_eeprom_i2c_addr_arct(struct amdgpu_device *adev,
99 				       struct amdgpu_ras_eeprom_control *control)
100 {
101 	struct atom_context *atom_ctx = adev->mode_info.atom_context;
102 
103 	if (!control || !atom_ctx)
104 		return false;
105 
106 	if (strnstr(atom_ctx->vbios_version,
107 	            "D342",
108 		    sizeof(atom_ctx->vbios_version)))
109 		control->i2c_address = EEPROM_I2C_MADDR_ARCTURUS_D342;
110 	else
111 		control->i2c_address = EEPROM_I2C_MADDR_ARCTURUS;
112 
113 	return true;
114 }
115 
116 static bool __get_eeprom_i2c_addr(struct amdgpu_device *adev,
117 				  struct amdgpu_ras_eeprom_control *control)
118 {
119 	u8 i2c_addr;
120 
121 	if (!control)
122 		return false;
123 
124 	if (amdgpu_atomfirmware_ras_rom_addr(adev, &i2c_addr)) {
125 		/* The address given by VBIOS is an 8-bit, wire-format
126 		 * address, i.e. the most significant byte.
127 		 *
128 		 * Normalize it to a 19-bit EEPROM address. Remove the
129 		 * device type identifier and make it a 7-bit address;
130 		 * then make it a 19-bit EEPROM address. See top of
131 		 * amdgpu_eeprom.c.
132 		 */
133 		i2c_addr = (i2c_addr & 0x0F) >> 1;
134 		control->i2c_address = ((u32) i2c_addr) << 16;
135 
136 		return true;
137 	}
138 
139 	switch (adev->asic_type) {
140 	case CHIP_VEGA20:
141 		control->i2c_address = EEPROM_I2C_MADDR_VEGA20;
142 		break;
143 
144 	case CHIP_ARCTURUS:
145 		return __get_eeprom_i2c_addr_arct(adev, control);
146 
147 	case CHIP_SIENNA_CICHLID:
148 		control->i2c_address = EEPROM_I2C_MADDR_SIENNA_CICHLID;
149 		break;
150 
151 	case CHIP_ALDEBARAN:
152 		control->i2c_address = EEPROM_I2C_MADDR_ALDEBARAN;
153 		break;
154 
155 	default:
156 		return false;
157 	}
158 
159 	return true;
160 }
161 
162 static void
163 __encode_table_header_to_buf(struct amdgpu_ras_eeprom_table_header *hdr,
164 			     unsigned char *buf)
165 {
166 	u32 *pp = (uint32_t *)buf;
167 
168 	pp[0] = cpu_to_le32(hdr->header);
169 	pp[1] = cpu_to_le32(hdr->version);
170 	pp[2] = cpu_to_le32(hdr->first_rec_offset);
171 	pp[3] = cpu_to_le32(hdr->tbl_size);
172 	pp[4] = cpu_to_le32(hdr->checksum);
173 }
174 
175 static void
176 __decode_table_header_from_buf(struct amdgpu_ras_eeprom_table_header *hdr,
177 			       unsigned char *buf)
178 {
179 	u32 *pp = (uint32_t *)buf;
180 
181 	hdr->header	      = le32_to_cpu(pp[0]);
182 	hdr->version	      = le32_to_cpu(pp[1]);
183 	hdr->first_rec_offset = le32_to_cpu(pp[2]);
184 	hdr->tbl_size	      = le32_to_cpu(pp[3]);
185 	hdr->checksum	      = le32_to_cpu(pp[4]);
186 }
187 
188 static int __write_table_header(struct amdgpu_ras_eeprom_control *control)
189 {
190 	u8 buf[RAS_TABLE_HEADER_SIZE];
191 	struct amdgpu_device *adev = to_amdgpu_device(control);
192 	int res;
193 
194 	memset(buf, 0, sizeof(buf));
195 	__encode_table_header_to_buf(&control->tbl_hdr, buf);
196 
197 	/* i2c may be unstable in gpu reset */
198 	down_read(&adev->reset_domain->sem);
199 	res = amdgpu_eeprom_write(adev->pm.ras_eeprom_i2c_bus,
200 				  control->i2c_address +
201 				  control->ras_header_offset,
202 				  buf, RAS_TABLE_HEADER_SIZE);
203 	up_read(&adev->reset_domain->sem);
204 
205 	if (res < 0) {
206 		DRM_ERROR("Failed to write EEPROM table header:%d", res);
207 	} else if (res < RAS_TABLE_HEADER_SIZE) {
208 		DRM_ERROR("Short write:%d out of %d\n",
209 			  res, RAS_TABLE_HEADER_SIZE);
210 		res = -EIO;
211 	} else {
212 		res = 0;
213 	}
214 
215 	return res;
216 }
217 
218 static u8 __calc_hdr_byte_sum(const struct amdgpu_ras_eeprom_control *control)
219 {
220 	int ii;
221 	u8  *pp, csum;
222 	size_t sz;
223 
224 	/* Header checksum, skip checksum field in the calculation */
225 	sz = sizeof(control->tbl_hdr) - sizeof(control->tbl_hdr.checksum);
226 	pp = (u8 *) &control->tbl_hdr;
227 	csum = 0;
228 	for (ii = 0; ii < sz; ii++, pp++)
229 		csum += *pp;
230 
231 	return csum;
232 }
233 
234 static int amdgpu_ras_eeprom_correct_header_tag(
235 	struct amdgpu_ras_eeprom_control *control,
236 	uint32_t header)
237 {
238 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
239 	u8 *hh;
240 	int res;
241 	u8 csum;
242 
243 	csum = -hdr->checksum;
244 
245 	hh = (void *) &hdr->header;
246 	csum -= (hh[0] + hh[1] + hh[2] + hh[3]);
247 	hh = (void *) &header;
248 	csum += hh[0] + hh[1] + hh[2] + hh[3];
249 	csum = -csum;
250 	mutex_lock(&control->ras_tbl_mutex);
251 	hdr->header = header;
252 	hdr->checksum = csum;
253 	res = __write_table_header(control);
254 	mutex_unlock(&control->ras_tbl_mutex);
255 
256 	return res;
257 }
258 
259 /**
260  * amdgpu_ras_eeprom_reset_table -- Reset the RAS EEPROM table
261  * @control: pointer to control structure
262  *
263  * Reset the contents of the header of the RAS EEPROM table.
264  * Return 0 on success, -errno on error.
265  */
266 int amdgpu_ras_eeprom_reset_table(struct amdgpu_ras_eeprom_control *control)
267 {
268 	struct amdgpu_device *adev = to_amdgpu_device(control);
269 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
270 	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
271 	u8 csum;
272 	int res;
273 
274 	mutex_lock(&control->ras_tbl_mutex);
275 
276 	hdr->header = RAS_TABLE_HDR_VAL;
277 	hdr->version = RAS_TABLE_VER;
278 	hdr->first_rec_offset = RAS_RECORD_START;
279 	hdr->tbl_size = RAS_TABLE_HEADER_SIZE;
280 
281 	csum = __calc_hdr_byte_sum(control);
282 	csum = -csum;
283 	hdr->checksum = csum;
284 	res = __write_table_header(control);
285 
286 	control->ras_num_recs = 0;
287 	control->ras_fri = 0;
288 
289 	amdgpu_dpm_send_hbm_bad_pages_num(adev, control->ras_num_recs);
290 
291 	control->bad_channel_bitmap = 0;
292 	amdgpu_dpm_send_hbm_bad_channel_flag(adev, control->bad_channel_bitmap);
293 	con->update_channel_flag = false;
294 
295 	amdgpu_ras_debugfs_set_ret_size(control);
296 
297 	mutex_unlock(&control->ras_tbl_mutex);
298 
299 	return res;
300 }
301 
302 static void
303 __encode_table_record_to_buf(struct amdgpu_ras_eeprom_control *control,
304 			     struct eeprom_table_record *record,
305 			     unsigned char *buf)
306 {
307 	__le64 tmp = 0;
308 	int i = 0;
309 
310 	/* Next are all record fields according to EEPROM page spec in LE foramt */
311 	buf[i++] = record->err_type;
312 
313 	buf[i++] = record->bank;
314 
315 	tmp = cpu_to_le64(record->ts);
316 	memcpy(buf + i, &tmp, 8);
317 	i += 8;
318 
319 	tmp = cpu_to_le64((record->offset & 0xffffffffffff));
320 	memcpy(buf + i, &tmp, 6);
321 	i += 6;
322 
323 	buf[i++] = record->mem_channel;
324 	buf[i++] = record->mcumc_id;
325 
326 	tmp = cpu_to_le64((record->retired_page & 0xffffffffffff));
327 	memcpy(buf + i, &tmp, 6);
328 }
329 
330 static void
331 __decode_table_record_from_buf(struct amdgpu_ras_eeprom_control *control,
332 			       struct eeprom_table_record *record,
333 			       unsigned char *buf)
334 {
335 	__le64 tmp = 0;
336 	int i =  0;
337 
338 	/* Next are all record fields according to EEPROM page spec in LE foramt */
339 	record->err_type = buf[i++];
340 
341 	record->bank = buf[i++];
342 
343 	memcpy(&tmp, buf + i, 8);
344 	record->ts = le64_to_cpu(tmp);
345 	i += 8;
346 
347 	memcpy(&tmp, buf + i, 6);
348 	record->offset = (le64_to_cpu(tmp) & 0xffffffffffff);
349 	i += 6;
350 
351 	record->mem_channel = buf[i++];
352 	record->mcumc_id = buf[i++];
353 
354 	memcpy(&tmp, buf + i,  6);
355 	record->retired_page = (le64_to_cpu(tmp) & 0xffffffffffff);
356 }
357 
358 bool amdgpu_ras_eeprom_check_err_threshold(struct amdgpu_device *adev)
359 {
360 	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
361 
362 	if (!__is_ras_eeprom_supported(adev))
363 		return false;
364 
365 	/* skip check eeprom table for VEGA20 Gaming */
366 	if (!con)
367 		return false;
368 	else
369 		if (!(con->features & BIT(AMDGPU_RAS_BLOCK__UMC)))
370 			return false;
371 
372 	if (con->eeprom_control.tbl_hdr.header == RAS_TABLE_HDR_BAD) {
373 		dev_warn(adev->dev, "This GPU is in BAD status.");
374 		dev_warn(adev->dev, "Please retire it or set a larger "
375 			 "threshold value when reloading driver.\n");
376 		return true;
377 	}
378 
379 	return false;
380 }
381 
382 /**
383  * __amdgpu_ras_eeprom_write -- write indexed from buffer to EEPROM
384  * @control: pointer to control structure
385  * @buf: pointer to buffer containing data to write
386  * @fri: start writing at this index
387  * @num: number of records to write
388  *
389  * The caller must hold the table mutex in @control.
390  * Return 0 on success, -errno otherwise.
391  */
392 static int __amdgpu_ras_eeprom_write(struct amdgpu_ras_eeprom_control *control,
393 				     u8 *buf, const u32 fri, const u32 num)
394 {
395 	struct amdgpu_device *adev = to_amdgpu_device(control);
396 	u32 buf_size;
397 	int res;
398 
399 	/* i2c may be unstable in gpu reset */
400 	down_read(&adev->reset_domain->sem);
401 	buf_size = num * RAS_TABLE_RECORD_SIZE;
402 	res = amdgpu_eeprom_write(adev->pm.ras_eeprom_i2c_bus,
403 				  control->i2c_address +
404 				  RAS_INDEX_TO_OFFSET(control, fri),
405 				  buf, buf_size);
406 	up_read(&adev->reset_domain->sem);
407 	if (res < 0) {
408 		DRM_ERROR("Writing %d EEPROM table records error:%d",
409 			  num, res);
410 	} else if (res < buf_size) {
411 		/* Short write, return error.
412 		 */
413 		DRM_ERROR("Wrote %d records out of %d",
414 			  res / RAS_TABLE_RECORD_SIZE, num);
415 		res = -EIO;
416 	} else {
417 		res = 0;
418 	}
419 
420 	return res;
421 }
422 
423 static int
424 amdgpu_ras_eeprom_append_table(struct amdgpu_ras_eeprom_control *control,
425 			       struct eeprom_table_record *record,
426 			       const u32 num)
427 {
428 	struct amdgpu_ras *con = amdgpu_ras_get_context(to_amdgpu_device(control));
429 	u32 a, b, i;
430 	u8 *buf, *pp;
431 	int res;
432 
433 	buf = kcalloc(num, RAS_TABLE_RECORD_SIZE, GFP_KERNEL);
434 	if (!buf)
435 		return -ENOMEM;
436 
437 	/* Encode all of them in one go.
438 	 */
439 	pp = buf;
440 	for (i = 0; i < num; i++, pp += RAS_TABLE_RECORD_SIZE) {
441 		__encode_table_record_to_buf(control, &record[i], pp);
442 
443 		/* update bad channel bitmap */
444 		if (!(control->bad_channel_bitmap & (1 << record[i].mem_channel))) {
445 			control->bad_channel_bitmap |= 1 << record[i].mem_channel;
446 			con->update_channel_flag = true;
447 		}
448 	}
449 
450 	/* a, first record index to write into.
451 	 * b, last record index to write into.
452 	 * a = first index to read (fri) + number of records in the table,
453 	 * b = a + @num - 1.
454 	 * Let N = control->ras_max_num_record_count, then we have,
455 	 * case 0: 0 <= a <= b < N,
456 	 *   just append @num records starting at a;
457 	 * case 1: 0 <= a < N <= b,
458 	 *   append (N - a) records starting at a, and
459 	 *   append the remainder,  b % N + 1, starting at 0.
460 	 * case 2: 0 <= fri < N <= a <= b, then modulo N we get two subcases,
461 	 * case 2a: 0 <= a <= b < N
462 	 *   append num records starting at a; and fix fri if b overwrote it,
463 	 *   and since a <= b, if b overwrote it then a must've also,
464 	 *   and if b didn't overwrite it, then a didn't also.
465 	 * case 2b: 0 <= b < a < N
466 	 *   write num records starting at a, which wraps around 0=N
467 	 *   and overwrite fri unconditionally. Now from case 2a,
468 	 *   this means that b eclipsed fri to overwrite it and wrap
469 	 *   around 0 again, i.e. b = 2N+r pre modulo N, so we unconditionally
470 	 *   set fri = b + 1 (mod N).
471 	 * Now, since fri is updated in every case, except the trivial case 0,
472 	 * the number of records present in the table after writing, is,
473 	 * num_recs - 1 = b - fri (mod N), and we take the positive value,
474 	 * by adding an arbitrary multiple of N before taking the modulo N
475 	 * as shown below.
476 	 */
477 	a = control->ras_fri + control->ras_num_recs;
478 	b = a + num  - 1;
479 	if (b < control->ras_max_record_count) {
480 		res = __amdgpu_ras_eeprom_write(control, buf, a, num);
481 	} else if (a < control->ras_max_record_count) {
482 		u32 g0, g1;
483 
484 		g0 = control->ras_max_record_count - a;
485 		g1 = b % control->ras_max_record_count + 1;
486 		res = __amdgpu_ras_eeprom_write(control, buf, a, g0);
487 		if (res)
488 			goto Out;
489 		res = __amdgpu_ras_eeprom_write(control,
490 						buf + g0 * RAS_TABLE_RECORD_SIZE,
491 						0, g1);
492 		if (res)
493 			goto Out;
494 		if (g1 > control->ras_fri)
495 			control->ras_fri = g1 % control->ras_max_record_count;
496 	} else {
497 		a %= control->ras_max_record_count;
498 		b %= control->ras_max_record_count;
499 
500 		if (a <= b) {
501 			/* Note that, b - a + 1 = num. */
502 			res = __amdgpu_ras_eeprom_write(control, buf, a, num);
503 			if (res)
504 				goto Out;
505 			if (b >= control->ras_fri)
506 				control->ras_fri = (b + 1) % control->ras_max_record_count;
507 		} else {
508 			u32 g0, g1;
509 
510 			/* b < a, which means, we write from
511 			 * a to the end of the table, and from
512 			 * the start of the table to b.
513 			 */
514 			g0 = control->ras_max_record_count - a;
515 			g1 = b + 1;
516 			res = __amdgpu_ras_eeprom_write(control, buf, a, g0);
517 			if (res)
518 				goto Out;
519 			res = __amdgpu_ras_eeprom_write(control,
520 							buf + g0 * RAS_TABLE_RECORD_SIZE,
521 							0, g1);
522 			if (res)
523 				goto Out;
524 			control->ras_fri = g1 % control->ras_max_record_count;
525 		}
526 	}
527 	control->ras_num_recs = 1 + (control->ras_max_record_count + b
528 				     - control->ras_fri)
529 		% control->ras_max_record_count;
530 Out:
531 	kfree(buf);
532 	return res;
533 }
534 
535 static int
536 amdgpu_ras_eeprom_update_header(struct amdgpu_ras_eeprom_control *control)
537 {
538 	struct amdgpu_device *adev = to_amdgpu_device(control);
539 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
540 	u8 *buf, *pp, csum;
541 	u32 buf_size;
542 	int res;
543 
544 	/* Modify the header if it exceeds.
545 	 */
546 	if (amdgpu_bad_page_threshold != 0 &&
547 	    control->ras_num_recs >= ras->bad_page_cnt_threshold) {
548 		dev_warn(adev->dev,
549 			"Saved bad pages %d reaches threshold value %d\n",
550 			control->ras_num_recs, ras->bad_page_cnt_threshold);
551 		control->tbl_hdr.header = RAS_TABLE_HDR_BAD;
552 	}
553 
554 	control->tbl_hdr.version = RAS_TABLE_VER;
555 	control->tbl_hdr.first_rec_offset = RAS_INDEX_TO_OFFSET(control, control->ras_fri);
556 	control->tbl_hdr.tbl_size = RAS_TABLE_HEADER_SIZE + control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
557 	control->tbl_hdr.checksum = 0;
558 
559 	buf_size = control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
560 	buf = kcalloc(control->ras_num_recs, RAS_TABLE_RECORD_SIZE, GFP_KERNEL);
561 	if (!buf) {
562 		DRM_ERROR("allocating memory for table of size %d bytes failed\n",
563 			  control->tbl_hdr.tbl_size);
564 		res = -ENOMEM;
565 		goto Out;
566 	}
567 
568 	down_read(&adev->reset_domain->sem);
569 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
570 				 control->i2c_address +
571 				 control->ras_record_offset,
572 				 buf, buf_size);
573 	up_read(&adev->reset_domain->sem);
574 	if (res < 0) {
575 		DRM_ERROR("EEPROM failed reading records:%d\n",
576 			  res);
577 		goto Out;
578 	} else if (res < buf_size) {
579 		DRM_ERROR("EEPROM read %d out of %d bytes\n",
580 			  res, buf_size);
581 		res = -EIO;
582 		goto Out;
583 	}
584 
585 	/* Recalc the checksum.
586 	 */
587 	csum = 0;
588 	for (pp = buf; pp < buf + buf_size; pp++)
589 		csum += *pp;
590 
591 	csum += __calc_hdr_byte_sum(control);
592 	/* avoid sign extension when assigning to "checksum" */
593 	csum = -csum;
594 	control->tbl_hdr.checksum = csum;
595 	res = __write_table_header(control);
596 Out:
597 	kfree(buf);
598 	return res;
599 }
600 
601 /**
602  * amdgpu_ras_eeprom_append -- append records to the EEPROM RAS table
603  * @control: pointer to control structure
604  * @record: array of records to append
605  * @num: number of records in @record array
606  *
607  * Append @num records to the table, calculate the checksum and write
608  * the table back to EEPROM. The maximum number of records that
609  * can be appended is between 1 and control->ras_max_record_count,
610  * regardless of how many records are already stored in the table.
611  *
612  * Return 0 on success or if EEPROM is not supported, -errno on error.
613  */
614 int amdgpu_ras_eeprom_append(struct amdgpu_ras_eeprom_control *control,
615 			     struct eeprom_table_record *record,
616 			     const u32 num)
617 {
618 	struct amdgpu_device *adev = to_amdgpu_device(control);
619 	int res;
620 
621 	if (!__is_ras_eeprom_supported(adev))
622 		return 0;
623 
624 	if (num == 0) {
625 		DRM_ERROR("will not append 0 records\n");
626 		return -EINVAL;
627 	} else if (num > control->ras_max_record_count) {
628 		DRM_ERROR("cannot append %d records than the size of table %d\n",
629 			  num, control->ras_max_record_count);
630 		return -EINVAL;
631 	}
632 
633 	mutex_lock(&control->ras_tbl_mutex);
634 
635 	res = amdgpu_ras_eeprom_append_table(control, record, num);
636 	if (!res)
637 		res = amdgpu_ras_eeprom_update_header(control);
638 	if (!res)
639 		amdgpu_ras_debugfs_set_ret_size(control);
640 
641 	mutex_unlock(&control->ras_tbl_mutex);
642 	return res;
643 }
644 
645 /**
646  * __amdgpu_ras_eeprom_read -- read indexed from EEPROM into buffer
647  * @control: pointer to control structure
648  * @buf: pointer to buffer to read into
649  * @fri: first record index, start reading at this index, absolute index
650  * @num: number of records to read
651  *
652  * The caller must hold the table mutex in @control.
653  * Return 0 on success, -errno otherwise.
654  */
655 static int __amdgpu_ras_eeprom_read(struct amdgpu_ras_eeprom_control *control,
656 				    u8 *buf, const u32 fri, const u32 num)
657 {
658 	struct amdgpu_device *adev = to_amdgpu_device(control);
659 	u32 buf_size;
660 	int res;
661 
662 	/* i2c may be unstable in gpu reset */
663 	down_read(&adev->reset_domain->sem);
664 	buf_size = num * RAS_TABLE_RECORD_SIZE;
665 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
666 				 control->i2c_address +
667 				 RAS_INDEX_TO_OFFSET(control, fri),
668 				 buf, buf_size);
669 	up_read(&adev->reset_domain->sem);
670 	if (res < 0) {
671 		DRM_ERROR("Reading %d EEPROM table records error:%d",
672 			  num, res);
673 	} else if (res < buf_size) {
674 		/* Short read, return error.
675 		 */
676 		DRM_ERROR("Read %d records out of %d",
677 			  res / RAS_TABLE_RECORD_SIZE, num);
678 		res = -EIO;
679 	} else {
680 		res = 0;
681 	}
682 
683 	return res;
684 }
685 
686 /**
687  * amdgpu_ras_eeprom_read -- read EEPROM
688  * @control: pointer to control structure
689  * @record: array of records to read into
690  * @num: number of records in @record
691  *
692  * Reads num records from the RAS table in EEPROM and
693  * writes the data into @record array.
694  *
695  * Returns 0 on success, -errno on error.
696  */
697 int amdgpu_ras_eeprom_read(struct amdgpu_ras_eeprom_control *control,
698 			   struct eeprom_table_record *record,
699 			   const u32 num)
700 {
701 	struct amdgpu_device *adev = to_amdgpu_device(control);
702 	struct amdgpu_ras *con = amdgpu_ras_get_context(adev);
703 	int i, res;
704 	u8 *buf, *pp;
705 	u32 g0, g1;
706 
707 	if (!__is_ras_eeprom_supported(adev))
708 		return 0;
709 
710 	if (num == 0) {
711 		DRM_ERROR("will not read 0 records\n");
712 		return -EINVAL;
713 	} else if (num > control->ras_num_recs) {
714 		DRM_ERROR("too many records to read:%d available:%d\n",
715 			  num, control->ras_num_recs);
716 		return -EINVAL;
717 	}
718 
719 	buf = kcalloc(num, RAS_TABLE_RECORD_SIZE, GFP_KERNEL);
720 	if (!buf)
721 		return -ENOMEM;
722 
723 	/* Determine how many records to read, from the first record
724 	 * index, fri, to the end of the table, and from the beginning
725 	 * of the table, such that the total number of records is
726 	 * @num, and we handle wrap around when fri > 0 and
727 	 * fri + num > RAS_MAX_RECORD_COUNT.
728 	 *
729 	 * First we compute the index of the last element
730 	 * which would be fetched from each region,
731 	 * g0 is in [fri, fri + num - 1], and
732 	 * g1 is in [0, RAS_MAX_RECORD_COUNT - 1].
733 	 * Then, if g0 < RAS_MAX_RECORD_COUNT, the index of
734 	 * the last element to fetch, we set g0 to _the number_
735 	 * of elements to fetch, @num, since we know that the last
736 	 * indexed to be fetched does not exceed the table.
737 	 *
738 	 * If, however, g0 >= RAS_MAX_RECORD_COUNT, then
739 	 * we set g0 to the number of elements to read
740 	 * until the end of the table, and g1 to the number of
741 	 * elements to read from the beginning of the table.
742 	 */
743 	g0 = control->ras_fri + num - 1;
744 	g1 = g0 % control->ras_max_record_count;
745 	if (g0 < control->ras_max_record_count) {
746 		g0 = num;
747 		g1 = 0;
748 	} else {
749 		g0 = control->ras_max_record_count - control->ras_fri;
750 		g1 += 1;
751 	}
752 
753 	mutex_lock(&control->ras_tbl_mutex);
754 	res = __amdgpu_ras_eeprom_read(control, buf, control->ras_fri, g0);
755 	if (res)
756 		goto Out;
757 	if (g1) {
758 		res = __amdgpu_ras_eeprom_read(control,
759 					       buf + g0 * RAS_TABLE_RECORD_SIZE,
760 					       0, g1);
761 		if (res)
762 			goto Out;
763 	}
764 
765 	res = 0;
766 
767 	/* Read up everything? Then transform.
768 	 */
769 	pp = buf;
770 	for (i = 0; i < num; i++, pp += RAS_TABLE_RECORD_SIZE) {
771 		__decode_table_record_from_buf(control, &record[i], pp);
772 
773 		/* update bad channel bitmap */
774 		if (!(control->bad_channel_bitmap & (1 << record[i].mem_channel))) {
775 			control->bad_channel_bitmap |= 1 << record[i].mem_channel;
776 			con->update_channel_flag = true;
777 		}
778 	}
779 Out:
780 	kfree(buf);
781 	mutex_unlock(&control->ras_tbl_mutex);
782 
783 	return res;
784 }
785 
786 uint32_t amdgpu_ras_eeprom_max_record_count(void)
787 {
788 	return RAS_MAX_RECORD_COUNT;
789 }
790 
791 static ssize_t
792 amdgpu_ras_debugfs_eeprom_size_read(struct file *f, char __user *buf,
793 				    size_t size, loff_t *pos)
794 {
795 	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
796 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
797 	struct amdgpu_ras_eeprom_control *control = ras ? &ras->eeprom_control : NULL;
798 	u8 data[50];
799 	int res;
800 
801 	if (!size)
802 		return size;
803 
804 	if (!ras || !control) {
805 		res = snprintf(data, sizeof(data), "Not supported\n");
806 	} else {
807 		res = snprintf(data, sizeof(data), "%d bytes or %d records\n",
808 			       RAS_TBL_SIZE_BYTES, control->ras_max_record_count);
809 	}
810 
811 	if (*pos >= res)
812 		return 0;
813 
814 	res -= *pos;
815 	res = min_t(size_t, res, size);
816 
817 	if (copy_to_user(buf, &data[*pos], res))
818 		return -EFAULT;
819 
820 	*pos += res;
821 
822 	return res;
823 }
824 
825 const struct file_operations amdgpu_ras_debugfs_eeprom_size_ops = {
826 	.owner = THIS_MODULE,
827 	.read = amdgpu_ras_debugfs_eeprom_size_read,
828 	.write = NULL,
829 	.llseek = default_llseek,
830 };
831 
832 static const char *tbl_hdr_str = " Signature    Version  FirstOffs       Size   Checksum\n";
833 static const char *tbl_hdr_fmt = "0x%08X 0x%08X 0x%08X 0x%08X 0x%08X\n";
834 #define tbl_hdr_fmt_size (5 * (2+8) + 4 + 1)
835 static const char *rec_hdr_str = "Index  Offset ErrType Bank/CU          TimeStamp      Offs/Addr MemChl MCUMCID    RetiredPage\n";
836 static const char *rec_hdr_fmt = "%5d 0x%05X %7s    0x%02X 0x%016llX 0x%012llX   0x%02X    0x%02X 0x%012llX\n";
837 #define rec_hdr_fmt_size (5 + 1 + 7 + 1 + 7 + 1 + 7 + 1 + 18 + 1 + 14 + 1 + 6 + 1 + 7 + 1 + 14 + 1)
838 
839 static const char *record_err_type_str[AMDGPU_RAS_EEPROM_ERR_COUNT] = {
840 	"ignore",
841 	"re",
842 	"ue",
843 };
844 
845 static loff_t amdgpu_ras_debugfs_table_size(struct amdgpu_ras_eeprom_control *control)
846 {
847 	return strlen(tbl_hdr_str) + tbl_hdr_fmt_size +
848 		strlen(rec_hdr_str) + rec_hdr_fmt_size * control->ras_num_recs;
849 }
850 
851 void amdgpu_ras_debugfs_set_ret_size(struct amdgpu_ras_eeprom_control *control)
852 {
853 	struct amdgpu_ras *ras = container_of(control, struct amdgpu_ras,
854 					      eeprom_control);
855 	struct dentry *de = ras->de_ras_eeprom_table;
856 
857 	if (de)
858 		d_inode(de)->i_size = amdgpu_ras_debugfs_table_size(control);
859 }
860 
861 static ssize_t amdgpu_ras_debugfs_table_read(struct file *f, char __user *buf,
862 					     size_t size, loff_t *pos)
863 {
864 	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
865 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
866 	struct amdgpu_ras_eeprom_control *control = &ras->eeprom_control;
867 	const size_t orig_size = size;
868 	int res = -EFAULT;
869 	size_t data_len;
870 
871 	mutex_lock(&control->ras_tbl_mutex);
872 
873 	/* We want *pos - data_len > 0, which means there's
874 	 * bytes to be printed from data.
875 	 */
876 	data_len = strlen(tbl_hdr_str);
877 	if (*pos < data_len) {
878 		data_len -= *pos;
879 		data_len = min_t(size_t, data_len, size);
880 		if (copy_to_user(buf, &tbl_hdr_str[*pos], data_len))
881 			goto Out;
882 		buf += data_len;
883 		size -= data_len;
884 		*pos += data_len;
885 	}
886 
887 	data_len = strlen(tbl_hdr_str) + tbl_hdr_fmt_size;
888 	if (*pos < data_len && size > 0) {
889 		u8 data[tbl_hdr_fmt_size + 1];
890 		loff_t lpos;
891 
892 		snprintf(data, sizeof(data), tbl_hdr_fmt,
893 			 control->tbl_hdr.header,
894 			 control->tbl_hdr.version,
895 			 control->tbl_hdr.first_rec_offset,
896 			 control->tbl_hdr.tbl_size,
897 			 control->tbl_hdr.checksum);
898 
899 		data_len -= *pos;
900 		data_len = min_t(size_t, data_len, size);
901 		lpos = *pos - strlen(tbl_hdr_str);
902 		if (copy_to_user(buf, &data[lpos], data_len))
903 			goto Out;
904 		buf += data_len;
905 		size -= data_len;
906 		*pos += data_len;
907 	}
908 
909 	data_len = strlen(tbl_hdr_str) + tbl_hdr_fmt_size + strlen(rec_hdr_str);
910 	if (*pos < data_len && size > 0) {
911 		loff_t lpos;
912 
913 		data_len -= *pos;
914 		data_len = min_t(size_t, data_len, size);
915 		lpos = *pos - strlen(tbl_hdr_str) - tbl_hdr_fmt_size;
916 		if (copy_to_user(buf, &rec_hdr_str[lpos], data_len))
917 			goto Out;
918 		buf += data_len;
919 		size -= data_len;
920 		*pos += data_len;
921 	}
922 
923 	data_len = amdgpu_ras_debugfs_table_size(control);
924 	if (*pos < data_len && size > 0) {
925 		u8 dare[RAS_TABLE_RECORD_SIZE];
926 		u8 data[rec_hdr_fmt_size + 1];
927 		struct eeprom_table_record record;
928 		int s, r;
929 
930 		/* Find the starting record index
931 		 */
932 		s = *pos - strlen(tbl_hdr_str) - tbl_hdr_fmt_size -
933 			strlen(rec_hdr_str);
934 		s = s / rec_hdr_fmt_size;
935 		r = *pos - strlen(tbl_hdr_str) - tbl_hdr_fmt_size -
936 			strlen(rec_hdr_str);
937 		r = r % rec_hdr_fmt_size;
938 
939 		for ( ; size > 0 && s < control->ras_num_recs; s++) {
940 			u32 ai = RAS_RI_TO_AI(control, s);
941 			/* Read a single record
942 			 */
943 			res = __amdgpu_ras_eeprom_read(control, dare, ai, 1);
944 			if (res)
945 				goto Out;
946 			__decode_table_record_from_buf(control, &record, dare);
947 			snprintf(data, sizeof(data), rec_hdr_fmt,
948 				 s,
949 				 RAS_INDEX_TO_OFFSET(control, ai),
950 				 record_err_type_str[record.err_type],
951 				 record.bank,
952 				 record.ts,
953 				 record.offset,
954 				 record.mem_channel,
955 				 record.mcumc_id,
956 				 record.retired_page);
957 
958 			data_len = min_t(size_t, rec_hdr_fmt_size - r, size);
959 			if (copy_to_user(buf, &data[r], data_len)) {
960 				res = -EFAULT;
961 				goto Out;
962 			}
963 			buf += data_len;
964 			size -= data_len;
965 			*pos += data_len;
966 			r = 0;
967 		}
968 	}
969 	res = 0;
970 Out:
971 	mutex_unlock(&control->ras_tbl_mutex);
972 	return res < 0 ? res : orig_size - size;
973 }
974 
975 static ssize_t
976 amdgpu_ras_debugfs_eeprom_table_read(struct file *f, char __user *buf,
977 				     size_t size, loff_t *pos)
978 {
979 	struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
980 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
981 	struct amdgpu_ras_eeprom_control *control = ras ? &ras->eeprom_control : NULL;
982 	u8 data[81];
983 	int res;
984 
985 	if (!size)
986 		return size;
987 
988 	if (!ras || !control) {
989 		res = snprintf(data, sizeof(data), "Not supported\n");
990 		if (*pos >= res)
991 			return 0;
992 
993 		res -= *pos;
994 		res = min_t(size_t, res, size);
995 
996 		if (copy_to_user(buf, &data[*pos], res))
997 			return -EFAULT;
998 
999 		*pos += res;
1000 
1001 		return res;
1002 	} else {
1003 		return amdgpu_ras_debugfs_table_read(f, buf, size, pos);
1004 	}
1005 }
1006 
1007 const struct file_operations amdgpu_ras_debugfs_eeprom_table_ops = {
1008 	.owner = THIS_MODULE,
1009 	.read = amdgpu_ras_debugfs_eeprom_table_read,
1010 	.write = NULL,
1011 	.llseek = default_llseek,
1012 };
1013 
1014 /**
1015  * __verify_ras_table_checksum -- verify the RAS EEPROM table checksum
1016  * @control: pointer to control structure
1017  *
1018  * Check the checksum of the stored in EEPROM RAS table.
1019  *
1020  * Return 0 if the checksum is correct,
1021  * positive if it is not correct, and
1022  * -errno on I/O error.
1023  */
1024 static int __verify_ras_table_checksum(struct amdgpu_ras_eeprom_control *control)
1025 {
1026 	struct amdgpu_device *adev = to_amdgpu_device(control);
1027 	int buf_size, res;
1028 	u8  csum, *buf, *pp;
1029 
1030 	buf_size = RAS_TABLE_HEADER_SIZE +
1031 		control->ras_num_recs * RAS_TABLE_RECORD_SIZE;
1032 	buf = kzalloc(buf_size, GFP_KERNEL);
1033 	if (!buf) {
1034 		DRM_ERROR("Out of memory checking RAS table checksum.\n");
1035 		return -ENOMEM;
1036 	}
1037 
1038 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
1039 				 control->i2c_address +
1040 				 control->ras_header_offset,
1041 				 buf, buf_size);
1042 	if (res < buf_size) {
1043 		DRM_ERROR("Partial read for checksum, res:%d\n", res);
1044 		/* On partial reads, return -EIO.
1045 		 */
1046 		if (res >= 0)
1047 			res = -EIO;
1048 		goto Out;
1049 	}
1050 
1051 	csum = 0;
1052 	for (pp = buf; pp < buf + buf_size; pp++)
1053 		csum += *pp;
1054 Out:
1055 	kfree(buf);
1056 	return res < 0 ? res : csum;
1057 }
1058 
1059 int amdgpu_ras_eeprom_init(struct amdgpu_ras_eeprom_control *control,
1060 			   bool *exceed_err_limit)
1061 {
1062 	struct amdgpu_device *adev = to_amdgpu_device(control);
1063 	unsigned char buf[RAS_TABLE_HEADER_SIZE] = { 0 };
1064 	struct amdgpu_ras_eeprom_table_header *hdr = &control->tbl_hdr;
1065 	struct amdgpu_ras *ras = amdgpu_ras_get_context(adev);
1066 	int res;
1067 
1068 	*exceed_err_limit = false;
1069 
1070 	if (!__is_ras_eeprom_supported(adev))
1071 		return 0;
1072 
1073 	/* Verify i2c adapter is initialized */
1074 	if (!adev->pm.ras_eeprom_i2c_bus || !adev->pm.ras_eeprom_i2c_bus->algo)
1075 		return -ENOENT;
1076 
1077 	if (!__get_eeprom_i2c_addr(adev, control))
1078 		return -EINVAL;
1079 
1080 	control->ras_header_offset = RAS_HDR_START;
1081 	control->ras_record_offset = RAS_RECORD_START;
1082 	control->ras_max_record_count  = RAS_MAX_RECORD_COUNT;
1083 	mutex_init(&control->ras_tbl_mutex);
1084 
1085 	/* Read the table header from EEPROM address */
1086 	res = amdgpu_eeprom_read(adev->pm.ras_eeprom_i2c_bus,
1087 				 control->i2c_address + control->ras_header_offset,
1088 				 buf, RAS_TABLE_HEADER_SIZE);
1089 	if (res < RAS_TABLE_HEADER_SIZE) {
1090 		DRM_ERROR("Failed to read EEPROM table header, res:%d", res);
1091 		return res >= 0 ? -EIO : res;
1092 	}
1093 
1094 	__decode_table_header_from_buf(hdr, buf);
1095 
1096 	control->ras_num_recs = RAS_NUM_RECS(hdr);
1097 	control->ras_fri = RAS_OFFSET_TO_INDEX(control, hdr->first_rec_offset);
1098 
1099 	if (hdr->header == RAS_TABLE_HDR_VAL) {
1100 		DRM_DEBUG_DRIVER("Found existing EEPROM table with %d records",
1101 				 control->ras_num_recs);
1102 		res = __verify_ras_table_checksum(control);
1103 		if (res)
1104 			DRM_ERROR("RAS table incorrect checksum or error:%d\n",
1105 				  res);
1106 
1107 		/* Warn if we are at 90% of the threshold or above
1108 		 */
1109 		if (10 * control->ras_num_recs >= 9 * ras->bad_page_cnt_threshold)
1110 			dev_warn(adev->dev, "RAS records:%u exceeds 90%% of threshold:%d",
1111 					control->ras_num_recs,
1112 					ras->bad_page_cnt_threshold);
1113 	} else if (hdr->header == RAS_TABLE_HDR_BAD &&
1114 		   amdgpu_bad_page_threshold != 0) {
1115 		res = __verify_ras_table_checksum(control);
1116 		if (res)
1117 			DRM_ERROR("RAS Table incorrect checksum or error:%d\n",
1118 				  res);
1119 		if (ras->bad_page_cnt_threshold > control->ras_num_recs) {
1120 			/* This means that, the threshold was increased since
1121 			 * the last time the system was booted, and now,
1122 			 * ras->bad_page_cnt_threshold - control->num_recs > 0,
1123 			 * so that at least one more record can be saved,
1124 			 * before the page count threshold is reached.
1125 			 */
1126 			dev_info(adev->dev,
1127 				 "records:%d threshold:%d, resetting "
1128 				 "RAS table header signature",
1129 				 control->ras_num_recs,
1130 				 ras->bad_page_cnt_threshold);
1131 			res = amdgpu_ras_eeprom_correct_header_tag(control,
1132 								   RAS_TABLE_HDR_VAL);
1133 		} else {
1134 			dev_err(adev->dev, "RAS records:%d exceed threshold:%d",
1135 				control->ras_num_recs, ras->bad_page_cnt_threshold);
1136 			if (amdgpu_bad_page_threshold == -2) {
1137 				dev_warn(adev->dev, "GPU will be initialized due to bad_page_threshold = -2.");
1138 				res = 0;
1139 			} else {
1140 				*exceed_err_limit = true;
1141 				dev_err(adev->dev,
1142 					"RAS records:%d exceed threshold:%d, "
1143 					"GPU will not be initialized. Replace this GPU or increase the threshold",
1144 					control->ras_num_recs, ras->bad_page_cnt_threshold);
1145 			}
1146 		}
1147 	} else {
1148 		DRM_INFO("Creating a new EEPROM table");
1149 
1150 		res = amdgpu_ras_eeprom_reset_table(control);
1151 	}
1152 
1153 	return res < 0 ? res : 0;
1154 }
1155