xref: /linux/drivers/hwmon/pt5161l.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 
3 #include <linux/debugfs.h>
4 #include <linux/delay.h>
5 #include <linux/err.h>
6 #include <linux/i2c.h>
7 #include <linux/init.h>
8 #include <linux/hwmon.h>
9 #include <linux/module.h>
10 #include <linux/mutex.h>
11 
12 /* Aries current average temp ADC code CSR */
13 #define ARIES_CURRENT_AVG_TEMP_ADC_CSR	0x42c
14 
15 /* Device Load check register */
16 #define ARIES_CODE_LOAD_REG	0x605
17 /* Value indicating FW was loaded properly, [3:1] = 3'b111 */
18 #define ARIES_LOAD_CODE	0xe
19 
20 /* Main Micro Heartbeat register */
21 #define ARIES_MM_HEARTBEAT_ADDR	0x923
22 
23 /* Reg offset to specify Address for MM assisted accesses */
24 #define ARIES_MM_ASSIST_REG_ADDR_OFFSET	0xd99
25 /* Reg offset to specify Command for MM assisted accesses */
26 #define ARIES_MM_ASSIST_CMD_OFFSET	0xd9d
27 /* Reg offset to MM SPARE 0 used specify Address[7:0] */
28 #define ARIES_MM_ASSIST_SPARE_0_OFFSET	0xd9f
29 /* Reg offset to MM SPARE 3 used specify Data Byte 0 */
30 #define ARIES_MM_ASSIST_SPARE_3_OFFSET	0xda2
31 /* Wide register reads */
32 #define ARIES_MM_RD_WIDE_REG_2B	0x1d
33 #define ARIES_MM_RD_WIDE_REG_3B	0x1e
34 #define ARIES_MM_RD_WIDE_REG_4B	0x1f
35 #define ARIES_MM_RD_WIDE_REG_5B	0x20
36 
37 /* Time delay between checking MM status of EEPROM write (microseconds) */
38 #define ARIES_MM_STATUS_TIME	5000
39 
40 /* AL Main SRAM DMEM offset (A0) */
41 #define AL_MAIN_SRAM_DMEM_OFFSET	(64 * 1024)
42 /* SRAM read command */
43 #define AL_TG_RD_LOC_IND_SRAM	0x16
44 
45 /* Offset for main micro FW info */
46 #define ARIES_MAIN_MICRO_FW_INFO	(96 * 1024 - 128)
47 /* FW Info (Major) offset location in struct */
48 #define ARIES_MM_FW_VERSION_MAJOR	0
49 /* FW Info (Minor) offset location in struct */
50 #define ARIES_MM_FW_VERSION_MINOR	1
51 /* FW Info (Build no.) offset location in struct */
52 #define ARIES_MM_FW_VERSION_BUILD	2
53 
54 #define ARIES_TEMP_CAL_CODE_DEFAULT	84
55 
56 /* Struct defining FW version loaded on an Aries device */
57 struct pt5161l_fw_ver {
58 	u8 major;
59 	u8 minor;
60 	u16 build;
61 };
62 
63 /* Each client has this additional data */
64 struct pt5161l_data {
65 	struct i2c_client *client;
66 	struct dentry *debugfs;
67 	struct pt5161l_fw_ver fw_ver;
68 	struct mutex lock; /* for atomic I2C transactions */
69 	bool init_done;
70 	bool code_load_okay; /* indicate if code load reg value is expected */
71 	bool mm_heartbeat_okay; /* indicate if Main Micro heartbeat is good */
72 	bool mm_wide_reg_access; /* MM assisted wide register access */
73 };
74 
75 static struct dentry *pt5161l_debugfs_dir;
76 
77 /*
78  * Write multiple data bytes to Aries over I2C
79  */
80 static int pt5161l_write_block_data(struct pt5161l_data *data, u32 address,
81 				    u8 len, u8 *val)
82 {
83 	struct i2c_client *client = data->client;
84 	int ret;
85 	u8 remain_len = len;
86 	u8 xfer_len, curr_len;
87 	u8 buf[16];
88 	u8 cmd = 0x0F; /* [7]:pec_en, [4:2]:func, [1]:start, [0]:end */
89 	u8 config = 0x40; /* [6]:cfg_type, [4:1]:burst_len, [0]:address bit16 */
90 
91 	while (remain_len > 0) {
92 		if (remain_len > 4) {
93 			curr_len = 4;
94 			remain_len -= 4;
95 		} else {
96 			curr_len = remain_len;
97 			remain_len = 0;
98 		}
99 
100 		buf[0] = config | (curr_len - 1) << 1 | ((address >> 16) & 0x1);
101 		buf[1] = (address >> 8) & 0xff;
102 		buf[2] = address & 0xff;
103 		memcpy(&buf[3], val, curr_len);
104 
105 		xfer_len = 3 + curr_len;
106 		ret = i2c_smbus_write_block_data(client, cmd, xfer_len, buf);
107 		if (ret)
108 			return ret;
109 
110 		val += curr_len;
111 		address += curr_len;
112 	}
113 
114 	return 0;
115 }
116 
117 /*
118  * Read multiple data bytes from Aries over I2C
119  */
120 static int pt5161l_read_block_data(struct pt5161l_data *data, u32 address,
121 				   u8 len, u8 *val)
122 {
123 	struct i2c_client *client = data->client;
124 	int ret, tries;
125 	u8 remain_len = len;
126 	u8 curr_len;
127 	u8 wbuf[16], rbuf[24];
128 	u8 cmd = 0x08; /* [7]:pec_en, [4:2]:func, [1]:start, [0]:end */
129 	u8 config = 0x00; /* [6]:cfg_type, [4:1]:burst_len, [0]:address bit16 */
130 
131 	while (remain_len > 0) {
132 		if (remain_len > 16) {
133 			curr_len = 16;
134 			remain_len -= 16;
135 		} else {
136 			curr_len = remain_len;
137 			remain_len = 0;
138 		}
139 
140 		wbuf[0] = config | (curr_len - 1) << 1 |
141 			  ((address >> 16) & 0x1);
142 		wbuf[1] = (address >> 8) & 0xff;
143 		wbuf[2] = address & 0xff;
144 
145 		for (tries = 0; tries < 3; tries++) {
146 			ret = i2c_smbus_write_block_data(client, (cmd | 0x2), 3,
147 							 wbuf);
148 			if (ret)
149 				return ret;
150 
151 			ret = i2c_smbus_read_block_data(client, (cmd | 0x1),
152 							rbuf);
153 			if (ret == curr_len)
154 				break;
155 		}
156 		if (tries >= 3)
157 			return ret;
158 
159 		memcpy(val, rbuf, curr_len);
160 		val += curr_len;
161 		address += curr_len;
162 	}
163 
164 	return 0;
165 }
166 
167 static int pt5161l_read_wide_reg(struct pt5161l_data *data, u32 address,
168 				 u8 width, u8 *val)
169 {
170 	int ret, tries;
171 	u8 buf[8];
172 	u8 status;
173 
174 	/*
175 	 * Safely access wide registers using mailbox method to prevent
176 	 * risking conflict with Aries firmware; otherwise fallback to
177 	 * legacy, less secure method.
178 	 */
179 	if (data->mm_wide_reg_access) {
180 		buf[0] = address & 0xff;
181 		buf[1] = (address >> 8) & 0xff;
182 		buf[2] = (address >> 16) & 0x1;
183 		ret = pt5161l_write_block_data(data,
184 					       ARIES_MM_ASSIST_SPARE_0_OFFSET,
185 					       3, buf);
186 		if (ret)
187 			return ret;
188 
189 		/* Set command based on width */
190 		switch (width) {
191 		case 2:
192 			buf[0] = ARIES_MM_RD_WIDE_REG_2B;
193 			break;
194 		case 3:
195 			buf[0] = ARIES_MM_RD_WIDE_REG_3B;
196 			break;
197 		case 4:
198 			buf[0] = ARIES_MM_RD_WIDE_REG_4B;
199 			break;
200 		case 5:
201 			buf[0] = ARIES_MM_RD_WIDE_REG_5B;
202 			break;
203 		default:
204 			return -EINVAL;
205 		}
206 		ret = pt5161l_write_block_data(data, ARIES_MM_ASSIST_CMD_OFFSET,
207 					       1, buf);
208 		if (ret)
209 			return ret;
210 
211 		status = 0xff;
212 		for (tries = 0; tries < 100; tries++) {
213 			ret = pt5161l_read_block_data(data,
214 						      ARIES_MM_ASSIST_CMD_OFFSET,
215 						      1, &status);
216 			if (ret)
217 				return ret;
218 
219 			if (status == 0)
220 				break;
221 
222 			usleep_range(ARIES_MM_STATUS_TIME,
223 				     ARIES_MM_STATUS_TIME + 1000);
224 		}
225 		if (status != 0)
226 			return -ETIMEDOUT;
227 
228 		ret = pt5161l_read_block_data(data,
229 					      ARIES_MM_ASSIST_SPARE_3_OFFSET,
230 					      width, val);
231 		if (ret)
232 			return ret;
233 	} else {
234 		return pt5161l_read_block_data(data, address, width, val);
235 	}
236 
237 	return 0;
238 }
239 
240 /*
241  * Read multiple (up to eight) data bytes from micro SRAM over I2C
242  */
243 static int
244 pt5161l_read_block_data_main_micro_indirect(struct pt5161l_data *data,
245 					    u32 address, u8 len, u8 *val)
246 {
247 	int ret, tries;
248 	u8 buf[8];
249 	u8 i, status;
250 	u32 uind_offs = ARIES_MM_ASSIST_REG_ADDR_OFFSET;
251 	u32 eeprom_base, eeprom_addr;
252 
253 	/* No multi-byte indirect support here. Hence read a byte at a time */
254 	eeprom_base = address - AL_MAIN_SRAM_DMEM_OFFSET;
255 	for (i = 0; i < len; i++) {
256 		eeprom_addr = eeprom_base + i;
257 		buf[0] = eeprom_addr & 0xff;
258 		buf[1] = (eeprom_addr >> 8) & 0xff;
259 		buf[2] = (eeprom_addr >> 16) & 0xff;
260 		ret = pt5161l_write_block_data(data, uind_offs, 3, buf);
261 		if (ret)
262 			return ret;
263 
264 		buf[0] = AL_TG_RD_LOC_IND_SRAM;
265 		ret = pt5161l_write_block_data(data, uind_offs + 4, 1, buf);
266 		if (ret)
267 			return ret;
268 
269 		status = 0xff;
270 		for (tries = 0; tries < 255; tries++) {
271 			ret = pt5161l_read_block_data(data, uind_offs + 4, 1,
272 						      &status);
273 			if (ret)
274 				return ret;
275 
276 			if (status == 0)
277 				break;
278 		}
279 		if (status != 0)
280 			return -ETIMEDOUT;
281 
282 		ret = pt5161l_read_block_data(data, uind_offs + 3, 1, buf);
283 		if (ret)
284 			return ret;
285 
286 		val[i] = buf[0];
287 	}
288 
289 	return 0;
290 }
291 
292 /*
293  * Check firmware load status
294  */
295 static int pt5161l_fw_load_check(struct pt5161l_data *data)
296 {
297 	int ret;
298 	u8 buf[8];
299 
300 	ret = pt5161l_read_block_data(data, ARIES_CODE_LOAD_REG, 1, buf);
301 	if (ret)
302 		return ret;
303 
304 	if (buf[0] < ARIES_LOAD_CODE) {
305 		dev_dbg(&data->client->dev,
306 			"Code Load reg unexpected. Not all modules are loaded %x\n",
307 			buf[0]);
308 		data->code_load_okay = false;
309 	} else {
310 		data->code_load_okay = true;
311 	}
312 
313 	return 0;
314 }
315 
316 /*
317  * Check main micro heartbeat
318  */
319 static int pt5161l_heartbeat_check(struct pt5161l_data *data)
320 {
321 	int ret, tries;
322 	u8 buf[8];
323 	u8 heartbeat;
324 	bool hb_changed = false;
325 
326 	ret = pt5161l_read_block_data(data, ARIES_MM_HEARTBEAT_ADDR, 1, buf);
327 	if (ret)
328 		return ret;
329 
330 	heartbeat = buf[0];
331 	for (tries = 0; tries < 100; tries++) {
332 		ret = pt5161l_read_block_data(data, ARIES_MM_HEARTBEAT_ADDR, 1,
333 					      buf);
334 		if (ret)
335 			return ret;
336 
337 		if (buf[0] != heartbeat) {
338 			hb_changed = true;
339 			break;
340 		}
341 	}
342 	data->mm_heartbeat_okay = hb_changed;
343 
344 	return 0;
345 }
346 
347 /*
348  * Check the status of firmware
349  */
350 static int pt5161l_fwsts_check(struct pt5161l_data *data)
351 {
352 	int ret;
353 	u8 buf[8];
354 	u8 major = 0, minor = 0;
355 	u16 build = 0;
356 
357 	ret = pt5161l_fw_load_check(data);
358 	if (ret)
359 		return ret;
360 
361 	ret = pt5161l_heartbeat_check(data);
362 	if (ret)
363 		return ret;
364 
365 	if (data->code_load_okay && data->mm_heartbeat_okay) {
366 		ret = pt5161l_read_block_data_main_micro_indirect(data, ARIES_MAIN_MICRO_FW_INFO +
367 								  ARIES_MM_FW_VERSION_MAJOR,
368 								  1, &major);
369 		if (ret)
370 			return ret;
371 
372 		ret = pt5161l_read_block_data_main_micro_indirect(data, ARIES_MAIN_MICRO_FW_INFO +
373 								  ARIES_MM_FW_VERSION_MINOR,
374 								  1, &minor);
375 		if (ret)
376 			return ret;
377 
378 		ret = pt5161l_read_block_data_main_micro_indirect(data, ARIES_MAIN_MICRO_FW_INFO +
379 								  ARIES_MM_FW_VERSION_BUILD,
380 								  2, buf);
381 		if (ret)
382 			return ret;
383 		build = buf[1] << 8 | buf[0];
384 	}
385 	data->fw_ver.major = major;
386 	data->fw_ver.minor = minor;
387 	data->fw_ver.build = build;
388 
389 	return 0;
390 }
391 
392 static int pt5161l_fw_is_at_least(struct pt5161l_data *data, u8 major, u8 minor,
393 				  u16 build)
394 {
395 	u32 ver = major << 24 | minor << 16 | build;
396 	u32 curr_ver = data->fw_ver.major << 24 | data->fw_ver.minor << 16 |
397 		       data->fw_ver.build;
398 
399 	if (curr_ver >= ver)
400 		return true;
401 
402 	return false;
403 }
404 
405 static int pt5161l_init_dev(struct pt5161l_data *data)
406 {
407 	int ret;
408 
409 	mutex_lock(&data->lock);
410 	ret = pt5161l_fwsts_check(data);
411 	mutex_unlock(&data->lock);
412 	if (ret)
413 		return ret;
414 
415 	/* Firmware 2.2.0 enables safe access to wide registers */
416 	if (pt5161l_fw_is_at_least(data, 2, 2, 0))
417 		data->mm_wide_reg_access = true;
418 
419 	data->init_done = true;
420 
421 	return 0;
422 }
423 
424 static int pt5161l_read(struct device *dev, enum hwmon_sensor_types type,
425 			u32 attr, int channel, long *val)
426 {
427 	struct pt5161l_data *data = dev_get_drvdata(dev);
428 	int ret;
429 	u8 buf[8];
430 	long adc_code;
431 
432 	switch (attr) {
433 	case hwmon_temp_input:
434 		if (!data->init_done) {
435 			ret = pt5161l_init_dev(data);
436 			if (ret)
437 				return ret;
438 		}
439 
440 		mutex_lock(&data->lock);
441 		ret = pt5161l_read_wide_reg(data,
442 					    ARIES_CURRENT_AVG_TEMP_ADC_CSR, 4,
443 					    buf);
444 		mutex_unlock(&data->lock);
445 		if (ret) {
446 			dev_dbg(dev, "Read adc_code failed %d\n", ret);
447 			return ret;
448 		}
449 
450 		adc_code = buf[3] << 24 | buf[2] << 16 | buf[1] << 8 | buf[0];
451 		if (adc_code == 0 || adc_code >= 0x3ff) {
452 			dev_dbg(dev, "Invalid adc_code %lx\n", adc_code);
453 			return -EIO;
454 		}
455 
456 		*val = 110000 +
457 		       ((adc_code - (ARIES_TEMP_CAL_CODE_DEFAULT + 250)) *
458 			-320);
459 		break;
460 	default:
461 		return -EOPNOTSUPP;
462 	}
463 
464 	return 0;
465 }
466 
467 static umode_t pt5161l_is_visible(const void *data,
468 				  enum hwmon_sensor_types type, u32 attr,
469 				  int channel)
470 {
471 	switch (attr) {
472 	case hwmon_temp_input:
473 		return 0444;
474 	default:
475 		break;
476 	}
477 
478 	return 0;
479 }
480 
481 static const struct hwmon_channel_info *pt5161l_info[] = {
482 	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
483 	NULL
484 };
485 
486 static const struct hwmon_ops pt5161l_hwmon_ops = {
487 	.is_visible = pt5161l_is_visible,
488 	.read = pt5161l_read,
489 };
490 
491 static const struct hwmon_chip_info pt5161l_chip_info = {
492 	.ops = &pt5161l_hwmon_ops,
493 	.info = pt5161l_info,
494 };
495 
496 static ssize_t pt5161l_debugfs_read_fw_ver(struct file *file, char __user *buf,
497 					   size_t count, loff_t *ppos)
498 {
499 	struct pt5161l_data *data = file->private_data;
500 	int ret;
501 	char ver[32];
502 
503 	mutex_lock(&data->lock);
504 	ret = pt5161l_fwsts_check(data);
505 	mutex_unlock(&data->lock);
506 	if (ret)
507 		return ret;
508 
509 	ret = snprintf(ver, sizeof(ver), "%u.%u.%u\n", data->fw_ver.major,
510 		       data->fw_ver.minor, data->fw_ver.build);
511 
512 	return simple_read_from_buffer(buf, count, ppos, ver, ret);
513 }
514 
515 static const struct file_operations pt5161l_debugfs_ops_fw_ver = {
516 	.read = pt5161l_debugfs_read_fw_ver,
517 	.open = simple_open,
518 };
519 
520 static ssize_t pt5161l_debugfs_read_fw_load_sts(struct file *file,
521 						char __user *buf, size_t count,
522 						loff_t *ppos)
523 {
524 	struct pt5161l_data *data = file->private_data;
525 	int ret;
526 	bool status = false;
527 	char health[16];
528 
529 	mutex_lock(&data->lock);
530 	ret = pt5161l_fw_load_check(data);
531 	mutex_unlock(&data->lock);
532 	if (ret == 0)
533 		status = data->code_load_okay;
534 
535 	ret = snprintf(health, sizeof(health), "%s\n",
536 		       status ? "normal" : "abnormal");
537 
538 	return simple_read_from_buffer(buf, count, ppos, health, ret);
539 }
540 
541 static const struct file_operations pt5161l_debugfs_ops_fw_load_sts = {
542 	.read = pt5161l_debugfs_read_fw_load_sts,
543 	.open = simple_open,
544 };
545 
546 static ssize_t pt5161l_debugfs_read_hb_sts(struct file *file, char __user *buf,
547 					   size_t count, loff_t *ppos)
548 {
549 	struct pt5161l_data *data = file->private_data;
550 	int ret;
551 	bool status = false;
552 	char health[16];
553 
554 	mutex_lock(&data->lock);
555 	ret = pt5161l_heartbeat_check(data);
556 	mutex_unlock(&data->lock);
557 	if (ret == 0)
558 		status = data->mm_heartbeat_okay;
559 
560 	ret = snprintf(health, sizeof(health), "%s\n",
561 		       status ? "normal" : "abnormal");
562 
563 	return simple_read_from_buffer(buf, count, ppos, health, ret);
564 }
565 
566 static const struct file_operations pt5161l_debugfs_ops_hb_sts = {
567 	.read = pt5161l_debugfs_read_hb_sts,
568 	.open = simple_open,
569 };
570 
571 static int pt5161l_init_debugfs(struct pt5161l_data *data)
572 {
573 	data->debugfs = debugfs_create_dir(dev_name(&data->client->dev),
574 					   pt5161l_debugfs_dir);
575 
576 	debugfs_create_file("fw_ver", 0444, data->debugfs, data,
577 			    &pt5161l_debugfs_ops_fw_ver);
578 
579 	debugfs_create_file("fw_load_status", 0444, data->debugfs, data,
580 			    &pt5161l_debugfs_ops_fw_load_sts);
581 
582 	debugfs_create_file("heartbeat_status", 0444, data->debugfs, data,
583 			    &pt5161l_debugfs_ops_hb_sts);
584 
585 	return 0;
586 }
587 
588 static int pt5161l_probe(struct i2c_client *client)
589 {
590 	struct device *dev = &client->dev;
591 	struct device *hwmon_dev;
592 	struct pt5161l_data *data;
593 
594 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
595 	if (!data)
596 		return -ENOMEM;
597 
598 	data->client = client;
599 	mutex_init(&data->lock);
600 	pt5161l_init_dev(data);
601 	dev_set_drvdata(dev, data);
602 
603 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
604 							 data,
605 							 &pt5161l_chip_info,
606 							 NULL);
607 
608 	pt5161l_init_debugfs(data);
609 
610 	return PTR_ERR_OR_ZERO(hwmon_dev);
611 }
612 
613 static void pt5161l_remove(struct i2c_client *client)
614 {
615 	struct pt5161l_data *data = i2c_get_clientdata(client);
616 
617 	debugfs_remove_recursive(data->debugfs);
618 }
619 
620 static const struct of_device_id __maybe_unused pt5161l_of_match[] = {
621 	{ .compatible = "asteralabs,pt5161l" },
622 	{},
623 };
624 MODULE_DEVICE_TABLE(of, pt5161l_of_match);
625 
626 static const struct acpi_device_id __maybe_unused pt5161l_acpi_match[] = {
627 	{ "PT5161L", 0 },
628 	{},
629 };
630 MODULE_DEVICE_TABLE(acpi, pt5161l_acpi_match);
631 
632 static const struct i2c_device_id pt5161l_id[] = {
633 	{ "pt5161l", 0 },
634 	{}
635 };
636 MODULE_DEVICE_TABLE(i2c, pt5161l_id);
637 
638 static struct i2c_driver pt5161l_driver = {
639 	.class = I2C_CLASS_HWMON,
640 	.driver = {
641 		.name = "pt5161l",
642 		.of_match_table = of_match_ptr(pt5161l_of_match),
643 		.acpi_match_table = ACPI_PTR(pt5161l_acpi_match),
644 	},
645 	.probe = pt5161l_probe,
646 	.remove = pt5161l_remove,
647 	.id_table = pt5161l_id,
648 };
649 
650 static int __init pt5161l_init(void)
651 {
652 	pt5161l_debugfs_dir = debugfs_create_dir("pt5161l", NULL);
653 	return i2c_add_driver(&pt5161l_driver);
654 }
655 
656 static void __exit pt5161l_exit(void)
657 {
658 	i2c_del_driver(&pt5161l_driver);
659 	debugfs_remove_recursive(pt5161l_debugfs_dir);
660 }
661 
662 module_init(pt5161l_init);
663 module_exit(pt5161l_exit);
664 
665 MODULE_AUTHOR("Cosmo Chou <cosmo.chou@quantatw.com>");
666 MODULE_DESCRIPTION("Hwmon driver for Astera Labs Aries PCIe retimer");
667 MODULE_LICENSE("GPL");
668