xref: /linux/drivers/platform/x86/intel/vsec.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
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/cleanup.h>
19 #include <linux/delay.h>
20 #include <linux/kernel.h>
21 #include <linux/idr.h>
22 #include <linux/module.h>
23 #include <linux/pci.h>
24 #include <linux/types.h>
25 
26 #include "vsec.h"
27 
28 #define PMT_XA_START			0
29 #define PMT_XA_MAX			INT_MAX
30 #define PMT_XA_LIMIT			XA_LIMIT(PMT_XA_START, PMT_XA_MAX)
31 
32 static DEFINE_IDA(intel_vsec_ida);
33 static DEFINE_IDA(intel_vsec_sdsi_ida);
34 static DEFINE_XARRAY_ALLOC(auxdev_array);
35 
36 static const char *intel_vsec_name(enum intel_vsec_id id)
37 {
38 	switch (id) {
39 	case VSEC_ID_TELEMETRY:
40 		return "telemetry";
41 
42 	case VSEC_ID_WATCHER:
43 		return "watcher";
44 
45 	case VSEC_ID_CRASHLOG:
46 		return "crashlog";
47 
48 	case VSEC_ID_SDSI:
49 		return "sdsi";
50 
51 	case VSEC_ID_TPMI:
52 		return "tpmi";
53 
54 	default:
55 		return NULL;
56 	}
57 }
58 
59 static bool intel_vsec_supported(u16 id, unsigned long caps)
60 {
61 	switch (id) {
62 	case VSEC_ID_TELEMETRY:
63 		return !!(caps & VSEC_CAP_TELEMETRY);
64 	case VSEC_ID_WATCHER:
65 		return !!(caps & VSEC_CAP_WATCHER);
66 	case VSEC_ID_CRASHLOG:
67 		return !!(caps & VSEC_CAP_CRASHLOG);
68 	case VSEC_ID_SDSI:
69 		return !!(caps & VSEC_CAP_SDSI);
70 	case VSEC_ID_TPMI:
71 		return !!(caps & VSEC_CAP_TPMI);
72 	default:
73 		return false;
74 	}
75 }
76 
77 static void intel_vsec_remove_aux(void *data)
78 {
79 	auxiliary_device_delete(data);
80 	auxiliary_device_uninit(data);
81 }
82 
83 static DEFINE_MUTEX(vsec_ida_lock);
84 
85 static void intel_vsec_dev_release(struct device *dev)
86 {
87 	struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(dev);
88 
89 	xa_erase(&auxdev_array, intel_vsec_dev->id);
90 
91 	mutex_lock(&vsec_ida_lock);
92 	ida_free(intel_vsec_dev->ida, intel_vsec_dev->auxdev.id);
93 	mutex_unlock(&vsec_ida_lock);
94 
95 	kfree(intel_vsec_dev->resource);
96 	kfree(intel_vsec_dev);
97 }
98 
99 int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
100 		       struct intel_vsec_device *intel_vsec_dev,
101 		       const char *name)
102 {
103 	struct auxiliary_device *auxdev = &intel_vsec_dev->auxdev;
104 	int ret, id;
105 
106 	if (!parent)
107 		return -EINVAL;
108 
109 	ret = xa_alloc(&auxdev_array, &intel_vsec_dev->id, intel_vsec_dev,
110 		       PMT_XA_LIMIT, GFP_KERNEL);
111 	if (ret < 0) {
112 		kfree(intel_vsec_dev->resource);
113 		kfree(intel_vsec_dev);
114 		return ret;
115 	}
116 
117 	mutex_lock(&vsec_ida_lock);
118 	id = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
119 	mutex_unlock(&vsec_ida_lock);
120 	if (id < 0) {
121 		xa_erase(&auxdev_array, intel_vsec_dev->id);
122 		kfree(intel_vsec_dev->resource);
123 		kfree(intel_vsec_dev);
124 		return id;
125 	}
126 
127 	auxdev->id = id;
128 	auxdev->name = name;
129 	auxdev->dev.parent = parent;
130 	auxdev->dev.release = intel_vsec_dev_release;
131 
132 	ret = auxiliary_device_init(auxdev);
133 	if (ret < 0) {
134 		intel_vsec_dev_release(&auxdev->dev);
135 		return ret;
136 	}
137 
138 	ret = auxiliary_device_add(auxdev);
139 	if (ret < 0) {
140 		auxiliary_device_uninit(auxdev);
141 		return ret;
142 	}
143 
144 	return devm_add_action_or_reset(parent, intel_vsec_remove_aux,
145 				       auxdev);
146 }
147 EXPORT_SYMBOL_NS_GPL(intel_vsec_add_aux, INTEL_VSEC);
148 
149 static int intel_vsec_add_dev(struct pci_dev *pdev, struct intel_vsec_header *header,
150 			      struct intel_vsec_platform_info *info)
151 {
152 	struct intel_vsec_device __free(kfree) *intel_vsec_dev = NULL;
153 	struct resource __free(kfree) *res = NULL;
154 	struct resource *tmp;
155 	struct device *parent;
156 	unsigned long quirks = info->quirks;
157 	u64 base_addr;
158 	int i;
159 
160 	if (info->parent)
161 		parent = info->parent;
162 	else
163 		parent = &pdev->dev;
164 
165 	if (!intel_vsec_supported(header->id, info->caps))
166 		return -EINVAL;
167 
168 	if (!header->num_entries) {
169 		dev_dbg(&pdev->dev, "Invalid 0 entry count for header id %d\n", header->id);
170 		return -EINVAL;
171 	}
172 
173 	if (!header->entry_size) {
174 		dev_dbg(&pdev->dev, "Invalid 0 entry size for header id %d\n", header->id);
175 		return -EINVAL;
176 	}
177 
178 	intel_vsec_dev = kzalloc(sizeof(*intel_vsec_dev), GFP_KERNEL);
179 	if (!intel_vsec_dev)
180 		return -ENOMEM;
181 
182 	res = kcalloc(header->num_entries, sizeof(*res), GFP_KERNEL);
183 	if (!res)
184 		return -ENOMEM;
185 
186 	if (quirks & VSEC_QUIRK_TABLE_SHIFT)
187 		header->offset >>= TABLE_OFFSET_SHIFT;
188 
189 	if (info->base_addr)
190 		base_addr = info->base_addr;
191 	else
192 		base_addr = pdev->resource[header->tbir].start;
193 
194 	/*
195 	 * The DVSEC/VSEC contains the starting offset and count for a block of
196 	 * discovery tables. Create a resource array of these tables to the
197 	 * auxiliary device driver.
198 	 */
199 	for (i = 0, tmp = res; i < header->num_entries; i++, tmp++) {
200 		tmp->start = base_addr + header->offset + i * (header->entry_size * sizeof(u32));
201 		tmp->end = tmp->start + (header->entry_size * sizeof(u32)) - 1;
202 		tmp->flags = IORESOURCE_MEM;
203 
204 		/* Check resource is not in use */
205 		if (!request_mem_region(tmp->start, resource_size(tmp), ""))
206 			return -EBUSY;
207 
208 		release_mem_region(tmp->start, resource_size(tmp));
209 	}
210 
211 	intel_vsec_dev->pcidev = pdev;
212 	intel_vsec_dev->resource = no_free_ptr(res);
213 	intel_vsec_dev->num_resources = header->num_entries;
214 	intel_vsec_dev->quirks = info->quirks;
215 	intel_vsec_dev->base_addr = info->base_addr;
216 
217 	if (header->id == VSEC_ID_SDSI)
218 		intel_vsec_dev->ida = &intel_vsec_sdsi_ida;
219 	else
220 		intel_vsec_dev->ida = &intel_vsec_ida;
221 
222 	/*
223 	 * Pass the ownership of intel_vsec_dev and resource within it to
224 	 * intel_vsec_add_aux()
225 	 */
226 	return intel_vsec_add_aux(pdev, parent, no_free_ptr(intel_vsec_dev),
227 				  intel_vsec_name(header->id));
228 }
229 
230 static bool intel_vsec_walk_header(struct pci_dev *pdev,
231 				   struct intel_vsec_platform_info *info)
232 {
233 	struct intel_vsec_header **header = info->headers;
234 	bool have_devices = false;
235 	int ret;
236 
237 	for ( ; *header; header++) {
238 		ret = intel_vsec_add_dev(pdev, *header, info);
239 		if (!ret)
240 			have_devices = true;
241 	}
242 
243 	return have_devices;
244 }
245 
246 static bool intel_vsec_walk_dvsec(struct pci_dev *pdev,
247 				  struct intel_vsec_platform_info *info)
248 {
249 	bool have_devices = false;
250 	int pos = 0;
251 
252 	do {
253 		struct intel_vsec_header header;
254 		u32 table, hdr;
255 		u16 vid;
256 		int ret;
257 
258 		pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_DVSEC);
259 		if (!pos)
260 			break;
261 
262 		pci_read_config_dword(pdev, pos + PCI_DVSEC_HEADER1, &hdr);
263 		vid = PCI_DVSEC_HEADER1_VID(hdr);
264 		if (vid != PCI_VENDOR_ID_INTEL)
265 			continue;
266 
267 		/* Support only revision 1 */
268 		header.rev = PCI_DVSEC_HEADER1_REV(hdr);
269 		if (header.rev != 1) {
270 			dev_info(&pdev->dev, "Unsupported DVSEC revision %d\n", header.rev);
271 			continue;
272 		}
273 
274 		header.length = PCI_DVSEC_HEADER1_LEN(hdr);
275 
276 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES, &header.num_entries);
277 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE, &header.entry_size);
278 		pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE, &table);
279 
280 		header.tbir = INTEL_DVSEC_TABLE_BAR(table);
281 		header.offset = INTEL_DVSEC_TABLE_OFFSET(table);
282 
283 		pci_read_config_dword(pdev, pos + PCI_DVSEC_HEADER2, &hdr);
284 		header.id = PCI_DVSEC_HEADER2_ID(hdr);
285 
286 		ret = intel_vsec_add_dev(pdev, &header, info);
287 		if (ret)
288 			continue;
289 
290 		have_devices = true;
291 	} while (true);
292 
293 	return have_devices;
294 }
295 
296 static bool intel_vsec_walk_vsec(struct pci_dev *pdev,
297 				 struct intel_vsec_platform_info *info)
298 {
299 	bool have_devices = false;
300 	int pos = 0;
301 
302 	do {
303 		struct intel_vsec_header header;
304 		u32 table, hdr;
305 		int ret;
306 
307 		pos = pci_find_next_ext_capability(pdev, pos, PCI_EXT_CAP_ID_VNDR);
308 		if (!pos)
309 			break;
310 
311 		pci_read_config_dword(pdev, pos + PCI_VNDR_HEADER, &hdr);
312 
313 		/* Support only revision 1 */
314 		header.rev = PCI_VNDR_HEADER_REV(hdr);
315 		if (header.rev != 1) {
316 			dev_info(&pdev->dev, "Unsupported VSEC revision %d\n", header.rev);
317 			continue;
318 		}
319 
320 		header.id = PCI_VNDR_HEADER_ID(hdr);
321 		header.length = PCI_VNDR_HEADER_LEN(hdr);
322 
323 		/* entry, size, and table offset are the same as DVSEC */
324 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_ENTRIES, &header.num_entries);
325 		pci_read_config_byte(pdev, pos + INTEL_DVSEC_SIZE, &header.entry_size);
326 		pci_read_config_dword(pdev, pos + INTEL_DVSEC_TABLE, &table);
327 
328 		header.tbir = INTEL_DVSEC_TABLE_BAR(table);
329 		header.offset = INTEL_DVSEC_TABLE_OFFSET(table);
330 
331 		ret = intel_vsec_add_dev(pdev, &header, info);
332 		if (ret)
333 			continue;
334 
335 		have_devices = true;
336 	} while (true);
337 
338 	return have_devices;
339 }
340 
341 void intel_vsec_register(struct pci_dev *pdev,
342 			 struct intel_vsec_platform_info *info)
343 {
344 	if (!pdev || !info)
345 		return;
346 
347 	intel_vsec_walk_header(pdev, info);
348 }
349 EXPORT_SYMBOL_NS_GPL(intel_vsec_register, INTEL_VSEC);
350 
351 static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
352 {
353 	struct intel_vsec_platform_info *info;
354 	bool have_devices = false;
355 	int ret;
356 
357 	ret = pcim_enable_device(pdev);
358 	if (ret)
359 		return ret;
360 
361 	pci_save_state(pdev);
362 	info = (struct intel_vsec_platform_info *)id->driver_data;
363 	if (!info)
364 		return -EINVAL;
365 
366 	if (intel_vsec_walk_dvsec(pdev, info))
367 		have_devices = true;
368 
369 	if (intel_vsec_walk_vsec(pdev, info))
370 		have_devices = true;
371 
372 	if (info && (info->quirks & VSEC_QUIRK_NO_DVSEC) &&
373 	    intel_vsec_walk_header(pdev, info))
374 		have_devices = true;
375 
376 	if (!have_devices)
377 		return -ENODEV;
378 
379 	return 0;
380 }
381 
382 /* DG1 info */
383 static struct intel_vsec_header dg1_header = {
384 	.length = 0x10,
385 	.id = 2,
386 	.num_entries = 1,
387 	.entry_size = 3,
388 	.tbir = 0,
389 	.offset = 0x466000,
390 };
391 
392 static struct intel_vsec_header *dg1_headers[] = {
393 	&dg1_header,
394 	NULL
395 };
396 
397 static const struct intel_vsec_platform_info dg1_info = {
398 	.caps = VSEC_CAP_TELEMETRY,
399 	.headers = dg1_headers,
400 	.quirks = VSEC_QUIRK_NO_DVSEC | VSEC_QUIRK_EARLY_HW,
401 };
402 
403 /* MTL info */
404 static const struct intel_vsec_platform_info mtl_info = {
405 	.caps = VSEC_CAP_TELEMETRY,
406 };
407 
408 /* OOBMSM info */
409 static const struct intel_vsec_platform_info oobmsm_info = {
410 	.caps = VSEC_CAP_TELEMETRY | VSEC_CAP_SDSI | VSEC_CAP_TPMI,
411 };
412 
413 /* TGL info */
414 static const struct intel_vsec_platform_info tgl_info = {
415 	.caps = VSEC_CAP_TELEMETRY,
416 	.quirks = VSEC_QUIRK_TABLE_SHIFT | VSEC_QUIRK_EARLY_HW,
417 };
418 
419 /* LNL info */
420 static const struct intel_vsec_platform_info lnl_info = {
421 	.caps = VSEC_CAP_TELEMETRY | VSEC_CAP_WATCHER,
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 #define PCI_DEVICE_ID_INTEL_VSEC_LNL_M		0x647d
432 static const struct pci_device_id intel_vsec_pci_ids[] = {
433 	{ PCI_DEVICE_DATA(INTEL, VSEC_ADL, &tgl_info) },
434 	{ PCI_DEVICE_DATA(INTEL, VSEC_DG1, &dg1_info) },
435 	{ PCI_DEVICE_DATA(INTEL, VSEC_MTL_M, &mtl_info) },
436 	{ PCI_DEVICE_DATA(INTEL, VSEC_MTL_S, &mtl_info) },
437 	{ PCI_DEVICE_DATA(INTEL, VSEC_OOBMSM, &oobmsm_info) },
438 	{ PCI_DEVICE_DATA(INTEL, VSEC_RPL, &tgl_info) },
439 	{ PCI_DEVICE_DATA(INTEL, VSEC_TGL, &tgl_info) },
440 	{ PCI_DEVICE_DATA(INTEL, VSEC_LNL_M, &lnl_info) },
441 	{ }
442 };
443 MODULE_DEVICE_TABLE(pci, intel_vsec_pci_ids);
444 
445 static pci_ers_result_t intel_vsec_pci_error_detected(struct pci_dev *pdev,
446 						      pci_channel_state_t state)
447 {
448 	pci_ers_result_t status = PCI_ERS_RESULT_NEED_RESET;
449 
450 	dev_info(&pdev->dev, "PCI error detected, state %d", state);
451 
452 	if (state == pci_channel_io_perm_failure)
453 		status = PCI_ERS_RESULT_DISCONNECT;
454 	else
455 		pci_disable_device(pdev);
456 
457 	return status;
458 }
459 
460 static pci_ers_result_t intel_vsec_pci_slot_reset(struct pci_dev *pdev)
461 {
462 	struct intel_vsec_device *intel_vsec_dev;
463 	pci_ers_result_t status = PCI_ERS_RESULT_DISCONNECT;
464 	const struct pci_device_id *pci_dev_id;
465 	unsigned long index;
466 
467 	dev_info(&pdev->dev, "Resetting PCI slot\n");
468 
469 	msleep(2000);
470 	if (pci_enable_device(pdev)) {
471 		dev_info(&pdev->dev,
472 			 "Failed to re-enable PCI device after reset.\n");
473 		goto out;
474 	}
475 
476 	status = PCI_ERS_RESULT_RECOVERED;
477 
478 	xa_for_each(&auxdev_array, index, intel_vsec_dev) {
479 		/* check if pdev doesn't match */
480 		if (pdev != intel_vsec_dev->pcidev)
481 			continue;
482 		devm_release_action(&pdev->dev, intel_vsec_remove_aux,
483 				    &intel_vsec_dev->auxdev);
484 	}
485 	pci_disable_device(pdev);
486 	pci_restore_state(pdev);
487 	pci_dev_id = pci_match_id(intel_vsec_pci_ids, pdev);
488 	intel_vsec_pci_probe(pdev, pci_dev_id);
489 
490 out:
491 	return status;
492 }
493 
494 static void intel_vsec_pci_resume(struct pci_dev *pdev)
495 {
496 	dev_info(&pdev->dev, "Done resuming PCI device\n");
497 }
498 
499 static const struct pci_error_handlers intel_vsec_pci_err_handlers = {
500 	.error_detected = intel_vsec_pci_error_detected,
501 	.slot_reset = intel_vsec_pci_slot_reset,
502 	.resume = intel_vsec_pci_resume,
503 };
504 
505 static struct pci_driver intel_vsec_pci_driver = {
506 	.name = "intel_vsec",
507 	.id_table = intel_vsec_pci_ids,
508 	.probe = intel_vsec_pci_probe,
509 	.err_handler = &intel_vsec_pci_err_handlers,
510 };
511 module_pci_driver(intel_vsec_pci_driver);
512 
513 MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>");
514 MODULE_DESCRIPTION("Intel Extended Capabilities auxiliary bus driver");
515 MODULE_LICENSE("GPL v2");
516