xref: /openbmc/linux/drivers/platform/x86/intel/vsec.c (revision 703e7713)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Intel Vendor Specific Extended Capabilities auxiliary bus driver
4  *
5  * Copyright (c) 2021, Intel Corporation.
6  * All Rights Reserved.
7  *
8  * Author: David E. Box <david.e.box@linux.intel.com>
9  *
10  * This driver discovers and creates auxiliary devices for Intel defined PCIe
11  * "Vendor Specific" and "Designated Vendor Specific" Extended Capabilities,
12  * VSEC and DVSEC respectively. The driver supports features on specific PCIe
13  * endpoints that exist primarily to expose them.
14  */
15 
16 #include <linux/auxiliary_bus.h>
17 #include <linux/bits.h>
18 #include <linux/delay.h>
19 #include <linux/kernel.h>
20 #include <linux/idr.h>
21 #include <linux/module.h>
22 #include <linux/pci.h>
23 #include <linux/types.h>
24 
25 #include "vsec.h"
26 
27 /* Intel DVSEC offsets */
28 #define INTEL_DVSEC_ENTRIES		0xA
29 #define INTEL_DVSEC_SIZE		0xB
30 #define INTEL_DVSEC_TABLE		0xC
31 #define INTEL_DVSEC_TABLE_BAR(x)	((x) & GENMASK(2, 0))
32 #define INTEL_DVSEC_TABLE_OFFSET(x)	((x) & GENMASK(31, 3))
33 #define TABLE_OFFSET_SHIFT		3
34 #define PMT_XA_START			0
35 #define PMT_XA_MAX			INT_MAX
36 #define PMT_XA_LIMIT			XA_LIMIT(PMT_XA_START, PMT_XA_MAX)
37 
38 static DEFINE_IDA(intel_vsec_ida);
39 static DEFINE_IDA(intel_vsec_sdsi_ida);
40 static DEFINE_XARRAY_ALLOC(auxdev_array);
41 
42 /**
43  * struct intel_vsec_header - Common fields of Intel VSEC and DVSEC registers.
44  * @rev:         Revision ID of the VSEC/DVSEC register space
45  * @length:      Length of the VSEC/DVSEC register space
46  * @id:          ID of the feature
47  * @num_entries: Number of instances of the feature
48  * @entry_size:  Size of the discovery table for each feature
49  * @tbir:        BAR containing the discovery tables
50  * @offset:      BAR offset of start of the first discovery table
51  */
52 struct intel_vsec_header {
53 	u8	rev;
54 	u16	length;
55 	u16	id;
56 	u8	num_entries;
57 	u8	entry_size;
58 	u8	tbir;
59 	u32	offset;
60 };
61 
62 enum intel_vsec_id {
63 	VSEC_ID_TELEMETRY	= 2,
64 	VSEC_ID_WATCHER		= 3,
65 	VSEC_ID_CRASHLOG	= 4,
66 	VSEC_ID_SDSI		= 65,
67 	VSEC_ID_TPMI		= 66,
68 };
69 
70 static const char *intel_vsec_name(enum intel_vsec_id id)
71 {
72 	switch (id) {
73 	case VSEC_ID_TELEMETRY:
74 		return "telemetry";
75 
76 	case VSEC_ID_WATCHER:
77 		return "watcher";
78 
79 	case VSEC_ID_CRASHLOG:
80 		return "crashlog";
81 
82 	case VSEC_ID_SDSI:
83 		return "sdsi";
84 
85 	case VSEC_ID_TPMI:
86 		return "tpmi";
87 
88 	default:
89 		return NULL;
90 	}
91 }
92 
93 static bool intel_vsec_supported(u16 id, unsigned long caps)
94 {
95 	switch (id) {
96 	case VSEC_ID_TELEMETRY:
97 		return !!(caps & VSEC_CAP_TELEMETRY);
98 	case VSEC_ID_WATCHER:
99 		return !!(caps & VSEC_CAP_WATCHER);
100 	case VSEC_ID_CRASHLOG:
101 		return !!(caps & VSEC_CAP_CRASHLOG);
102 	case VSEC_ID_SDSI:
103 		return !!(caps & VSEC_CAP_SDSI);
104 	case VSEC_ID_TPMI:
105 		return !!(caps & VSEC_CAP_TPMI);
106 	default:
107 		return false;
108 	}
109 }
110 
111 static void intel_vsec_remove_aux(void *data)
112 {
113 	auxiliary_device_delete(data);
114 	auxiliary_device_uninit(data);
115 }
116 
117 static DEFINE_MUTEX(vsec_ida_lock);
118 
119 static void intel_vsec_dev_release(struct device *dev)
120 {
121 	struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(dev);
122 
123 	mutex_lock(&vsec_ida_lock);
124 	ida_free(intel_vsec_dev->ida, intel_vsec_dev->auxdev.id);
125 	mutex_unlock(&vsec_ida_lock);
126 
127 	kfree(intel_vsec_dev->resource);
128 	kfree(intel_vsec_dev);
129 }
130 
131 int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
132 		       struct intel_vsec_device *intel_vsec_dev,
133 		       const char *name)
134 {
135 	struct auxiliary_device *auxdev = &intel_vsec_dev->auxdev;
136 	int ret, id;
137 
138 	mutex_lock(&vsec_ida_lock);
139 	ret = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
140 	mutex_unlock(&vsec_ida_lock);
141 	if (ret < 0) {
142 		kfree(intel_vsec_dev->resource);
143 		kfree(intel_vsec_dev);
144 		return ret;
145 	}
146 
147 	if (!parent)
148 		parent = &pdev->dev;
149 
150 	auxdev->id = ret;
151 	auxdev->name = name;
152 	auxdev->dev.parent = parent;
153 	auxdev->dev.release = intel_vsec_dev_release;
154 
155 	ret = auxiliary_device_init(auxdev);
156 	if (ret < 0) {
157 		intel_vsec_dev_release(&auxdev->dev);
158 		return ret;
159 	}
160 
161 	ret = auxiliary_device_add(auxdev);
162 	if (ret < 0) {
163 		auxiliary_device_uninit(auxdev);
164 		return ret;
165 	}
166 
167 	ret = devm_add_action_or_reset(parent, intel_vsec_remove_aux,
168 				       auxdev);
169 	if (ret < 0)
170 		return ret;
171 
172 	/* Add auxdev to list */
173 	ret = xa_alloc(&auxdev_array, &id, intel_vsec_dev, PMT_XA_LIMIT,
174 		       GFP_KERNEL);
175 	if (ret)
176 		return ret;
177 
178 	return 0;
179 }
180 EXPORT_SYMBOL_NS_GPL(intel_vsec_add_aux, INTEL_VSEC);
181 
182 static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *header,
183 			      struct intel_vsec_platform_info *info)
184 {
185 	struct intel_vsec_device *intel_vsec_dev;
186 	struct resource *res, *tmp;
187 	unsigned long quirks = info->quirks;
188 	int i;
189 
190 	if (!intel_vsec_supported(header->id, info->caps))
191 		return -EINVAL;
192 
193 	if (!header->num_entries) {
194 		dev_dbg(&pdev->dev, "Invalid 0 entry count for header id %d\n", header->id);
195 		return -EINVAL;
196 	}
197 
198 	if (!header->entry_size) {
199 		dev_dbg(&pdev->dev, "Invalid 0 entry size for header id %d\n", header->id);
200 		return -EINVAL;
201 	}
202 
203 	intel_vsec_dev = kzalloc(sizeof(*intel_vsec_dev), GFP_KERNEL);
204 	if (!intel_vsec_dev)
205 		return -ENOMEM;
206 
207 	res = kcalloc(header->num_entries, sizeof(*res), GFP_KERNEL);
208 	if (!res) {
209 		kfree(intel_vsec_dev);
210 		return -ENOMEM;
211 	}
212 
213 	if (quirks & VSEC_QUIRK_TABLE_SHIFT)
214 		header->offset >>= TABLE_OFFSET_SHIFT;
215 
216 	/*
217 	 * The DVSEC/VSEC contains the starting offset and count for a block of
218 	 * discovery tables. Create a resource array of these tables to the
219 	 * auxiliary device driver.
220 	 */
221 	for (i = 0, tmp = res; i < header->num_entries; i++, tmp++) {
222 		tmp->start = pdev->resource[header->tbir].start +
223 			     header->offset + i * (header->entry_size * sizeof(u32));
224 		tmp->end = tmp->start + (header->entry_size * sizeof(u32)) - 1;
225 		tmp->flags = IORESOURCE_MEM;
226 	}
227 
228 	intel_vsec_dev->pcidev = pdev;
229 	intel_vsec_dev->resource = res;
230 	intel_vsec_dev->num_resources = header->num_entries;
231 	intel_vsec_dev->info = info;
232 
233 	if (header->id == VSEC_ID_SDSI)
234 		intel_vsec_dev->ida = &intel_vsec_sdsi_ida;
235 	else
236 		intel_vsec_dev->ida = &intel_vsec_ida;
237 
238 	return intel_vsec_add_aux(pdev, NULL, intel_vsec_dev,
239 				  intel_vsec_name(header->id));
240 }
241 
242 static bool intel_vsec_walk_header(struct pci_dev *pdev,
243 				   struct intel_vsec_platform_info *info)
244 {
245 	struct intel_vsec_header **header = info->headers;
246 	bool have_devices = false;
247 	int ret;
248 
249 	for ( ; *header; header++) {
250 		ret = intel_vsec_add_dev(pdev, *header, info);
251 		if (ret)
252 			dev_info(&pdev->dev, "Could not add device for VSEC id %d\n",
253 				 (*header)->id);
254 		else
255 			have_devices = true;
256 	}
257 
258 	return have_devices;
259 }
260 
261 static bool intel_vsec_walk_dvsec(struct pci_dev *pdev,
262 				  struct intel_vsec_platform_info *info)
263 {
264 	bool have_devices = false;
265 	int pos = 0;
266 
267 	do {
268 		struct intel_vsec_header header;
269 		u32 table, hdr;
270 		u16 vid;
271 		int ret;
272 
273 		pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_DVSEC);
274 		if (!pos)
275 			break;
276 
277 		pci_read_config_dword(pdev, pos + PCI_DVSEC_HEADER1, &hdr);
278 		vid = PCI_DVSEC_HEADER1_VID(hdr);
279 		if (vid != PCI_VENDOR_ID_INTEL)
280 			continue;
281 
282 		/* Support only revision 1 */
283 		header.rev = PCI_DVSEC_HEADER1_REV(hdr);
284 		if (header.rev != 1) {
285 			dev_info(&pdev->dev, "Unsupported DVSEC revision %d\n", header.rev);
286 			continue;
287 		}
288 
289 		header.length = PCI_DVSEC_HEADER1_LEN(hdr);
290 
291 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES, &header.num_entries);
292 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE, &header.entry_size);
293 		pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE, &table);
294 
295 		header.tbir = INTEL_DVSEC_TABLE_BAR(table);
296 		header.offset = INTEL_DVSEC_TABLE_OFFSET(table);
297 
298 		pci_read_config_dword(pdev, pos + PCI_DVSEC_HEADER2, &hdr);
299 		header.id = PCI_DVSEC_HEADER2_ID(hdr);
300 
301 		ret = intel_vsec_add_dev(pdev, &header, info);
302 		if (ret)
303 			continue;
304 
305 		have_devices = true;
306 	} while (true);
307 
308 	return have_devices;
309 }
310 
311 static bool intel_vsec_walk_vsec(struct pci_dev *pdev,
312 				 struct intel_vsec_platform_info *info)
313 {
314 	bool have_devices = false;
315 	int pos = 0;
316 
317 	do {
318 		struct intel_vsec_header header;
319 		u32 table, hdr;
320 		int ret;
321 
322 		pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_VNDR);
323 		if (!pos)
324 			break;
325 
326 		pci_read_config_dword(pdev, pos + PCI_VNDR_HEADER, &hdr);
327 
328 		/* Support only revision 1 */
329 		header.rev = PCI_VNDR_HEADER_REV(hdr);
330 		if (header.rev != 1) {
331 			dev_info(&pdev->dev, "Unsupported VSEC revision %d\n", header.rev);
332 			continue;
333 		}
334 
335 		header.id = PCI_VNDR_HEADER_ID(hdr);
336 		header.length = PCI_VNDR_HEADER_LEN(hdr);
337 
338 		/* entry, size, and table offset are the same as DVSEC */
339 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES, &header.num_entries);
340 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE, &header.entry_size);
341 		pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE, &table);
342 
343 		header.tbir = INTEL_DVSEC_TABLE_BAR(table);
344 		header.offset = INTEL_DVSEC_TABLE_OFFSET(table);
345 
346 		ret = intel_vsec_add_dev(pdev, &header, info);
347 		if (ret)
348 			continue;
349 
350 		have_devices = true;
351 	} while (true);
352 
353 	return have_devices;
354 }
355 
356 static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
357 {
358 	struct intel_vsec_platform_info *info;
359 	bool have_devices = false;
360 	int ret;
361 
362 	ret = pcim_enable_device(pdev);
363 	if (ret)
364 		return ret;
365 
366 	pci_save_state(pdev);
367 	info = (struct intel_vsec_platform_info *)id->driver_data;
368 	if (!info)
369 		return -EINVAL;
370 
371 	if (intel_vsec_walk_dvsec(pdev, info))
372 		have_devices = true;
373 
374 	if (intel_vsec_walk_vsec(pdev, info))
375 		have_devices = true;
376 
377 	if (info && (info->quirks & VSEC_QUIRK_NO_DVSEC) &&
378 	    intel_vsec_walk_header(pdev, info))
379 		have_devices = true;
380 
381 	if (!have_devices)
382 		return -ENODEV;
383 
384 	return 0;
385 }
386 
387 /* DG1 info */
388 static struct intel_vsec_header dg1_header = {
389 	.length = 0x10,
390 	.id = 2,
391 	.num_entries = 1,
392 	.entry_size = 3,
393 	.tbir = 0,
394 	.offset = 0x466000,
395 };
396 
397 static struct intel_vsec_header *dg1_headers[] = {
398 	&dg1_header,
399 	NULL
400 };
401 
402 static const struct intel_vsec_platform_info dg1_info = {
403 	.caps = VSEC_CAP_TELEMETRY,
404 	.headers = dg1_headers,
405 	.quirks = VSEC_QUIRK_NO_DVSEC | VSEC_QUIRK_EARLY_HW,
406 };
407 
408 /* MTL info */
409 static const struct intel_vsec_platform_info mtl_info = {
410 	.caps = VSEC_CAP_TELEMETRY,
411 };
412 
413 /* OOBMSM info */
414 static const struct intel_vsec_platform_info oobmsm_info = {
415 	.caps = VSEC_CAP_TELEMETRY | VSEC_CAP_SDSI | VSEC_CAP_TPMI,
416 };
417 
418 /* TGL info */
419 static const struct intel_vsec_platform_info tgl_info = {
420 	.caps = VSEC_CAP_TELEMETRY,
421 	.quirks = VSEC_QUIRK_TABLE_SHIFT | VSEC_QUIRK_EARLY_HW,
422 };
423 
424 #define PCI_DEVICE_ID_INTEL_VSEC_ADL		0x467d
425 #define PCI_DEVICE_ID_INTEL_VSEC_DG1		0x490e
426 #define PCI_DEVICE_ID_INTEL_VSEC_MTL_M		0x7d0d
427 #define PCI_DEVICE_ID_INTEL_VSEC_MTL_S		0xad0d
428 #define PCI_DEVICE_ID_INTEL_VSEC_OOBMSM		0x09a7
429 #define PCI_DEVICE_ID_INTEL_VSEC_RPL		0xa77d
430 #define PCI_DEVICE_ID_INTEL_VSEC_TGL		0x9a0d
431 static const struct pci_device_id intel_vsec_pci_ids[] = {
432 	{ PCI_DEVICE_DATA(INTEL, VSEC_ADL, &tgl_info) },
433 	{ PCI_DEVICE_DATA(INTEL, VSEC_DG1, &dg1_info) },
434 	{ PCI_DEVICE_DATA(INTEL, VSEC_MTL_M, &mtl_info) },
435 	{ PCI_DEVICE_DATA(INTEL, VSEC_MTL_S, &mtl_info) },
436 	{ PCI_DEVICE_DATA(INTEL, VSEC_OOBMSM, &oobmsm_info) },
437 	{ PCI_DEVICE_DATA(INTEL, VSEC_RPL, &tgl_info) },
438 	{ PCI_DEVICE_DATA(INTEL, VSEC_TGL, &tgl_info) },
439 	{ }
440 };
441 MODULE_DEVICE_TABLE(pci, intel_vsec_pci_ids);
442 
443 static pci_ers_result_t intel_vsec_pci_error_detected(struct pci_dev *pdev,
444 						      pci_channel_state_t state)
445 {
446 	pci_ers_result_t status = PCI_ERS_RESULT_NEED_RESET;
447 
448 	dev_info(&pdev->dev, "PCI error detected, state %d", state);
449 
450 	if (state == pci_channel_io_perm_failure)
451 		status = PCI_ERS_RESULT_DISCONNECT;
452 	else
453 		pci_disable_device(pdev);
454 
455 	return status;
456 }
457 
458 static pci_ers_result_t intel_vsec_pci_slot_reset(struct pci_dev *pdev)
459 {
460 	struct intel_vsec_device *intel_vsec_dev;
461 	pci_ers_result_t status = PCI_ERS_RESULT_DISCONNECT;
462 	const struct pci_device_id *pci_dev_id;
463 	unsigned long index;
464 
465 	dev_info(&pdev->dev, "Resetting PCI slot\n");
466 
467 	msleep(2000);
468 	if (pci_enable_device(pdev)) {
469 		dev_info(&pdev->dev,
470 			 "Failed to re-enable PCI device after reset.\n");
471 		goto out;
472 	}
473 
474 	status = PCI_ERS_RESULT_RECOVERED;
475 
476 	xa_for_each(&auxdev_array, index, intel_vsec_dev) {
477 		/* check if pdev doesn't match */
478 		if (pdev != intel_vsec_dev->pcidev)
479 			continue;
480 		devm_release_action(&pdev->dev, intel_vsec_remove_aux,
481 				    &intel_vsec_dev->auxdev);
482 	}
483 	pci_disable_device(pdev);
484 	pci_restore_state(pdev);
485 	pci_dev_id = pci_match_id(intel_vsec_pci_ids, pdev);
486 	intel_vsec_pci_probe(pdev, pci_dev_id);
487 
488 out:
489 	return status;
490 }
491 
492 static void intel_vsec_pci_resume(struct pci_dev *pdev)
493 {
494 	dev_info(&pdev->dev, "Done resuming PCI device\n");
495 }
496 
497 static const struct pci_error_handlers intel_vsec_pci_err_handlers = {
498 	.error_detected = intel_vsec_pci_error_detected,
499 	.slot_reset = intel_vsec_pci_slot_reset,
500 	.resume = intel_vsec_pci_resume,
501 };
502 
503 static struct pci_driver intel_vsec_pci_driver = {
504 	.name = "intel_vsec",
505 	.id_table = intel_vsec_pci_ids,
506 	.probe = intel_vsec_pci_probe,
507 	.err_handler = &intel_vsec_pci_err_handlers,
508 };
509 module_pci_driver(intel_vsec_pci_driver);
510 
511 MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");
512 MODULE_DESCRIPTION("Intel Extended Capabilities auxiliary bus driver");
513 MODULE_LICENSE("GPL v2");
514