xref: /linux/drivers/platform/x86/intel/tpmi.c (revision 021bc4b9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * intel-tpmi : Driver to enumerate TPMI features and create devices
4  *
5  * Copyright (c) 2023, Intel Corporation.
6  * All Rights Reserved.
7  *
8  * The TPMI (Topology Aware Register and PM Capsule Interface) provides a
9  * flexible, extendable and PCIe enumerable MMIO interface for PM features.
10  *
11  * For example Intel RAPL (Running Average Power Limit) provides a MMIO
12  * interface using TPMI. This has advantage over traditional MSR
13  * (Model Specific Register) interface, where a thread needs to be scheduled
14  * on the target CPU to read or write. Also the RAPL features vary between
15  * CPU models, and hence lot of model specific code. Here TPMI provides an
16  * architectural interface by providing hierarchical tables and fields,
17  * which will not need any model specific implementation.
18  *
19  * The TPMI interface uses a PCI VSEC structure to expose the location of
20  * MMIO region.
21  *
22  * This VSEC structure is present in the PCI configuration space of the
23  * Intel Out-of-Band (OOB) device, which  is handled by the Intel VSEC
24  * driver. The Intel VSEC driver parses VSEC structures present in the PCI
25  * configuration space of the given device and creates an auxiliary device
26  * object for each of them. In particular, it creates an auxiliary device
27  * object representing TPMI that can be bound by an auxiliary driver.
28  *
29  * This TPMI driver will bind to the TPMI auxiliary device object created
30  * by the Intel VSEC driver.
31  *
32  * The TPMI specification defines a PFS (PM Feature Structure) table.
33  * This table is present in the TPMI MMIO region. The starting address
34  * of PFS is derived from the tBIR (Bar Indicator Register) and "Address"
35  * field from the VSEC header.
36  *
37  * Each TPMI PM feature has one entry in the PFS with a unique TPMI
38  * ID and its access details. The TPMI driver creates device nodes
39  * for the supported PM features.
40  *
41  * The names of the devices created by the TPMI driver start with the
42  * "intel_vsec.tpmi-" prefix which is followed by a specific name of the
43  * given PM feature (for example, "intel_vsec.tpmi-rapl.0").
44  *
45  * The device nodes are create by using interface "intel_vsec_add_aux()"
46  * provided by the Intel VSEC driver.
47  */
48 
49 #include <linux/auxiliary_bus.h>
50 #include <linux/bitfield.h>
51 #include <linux/debugfs.h>
52 #include <linux/delay.h>
53 #include <linux/intel_tpmi.h>
54 #include <linux/io.h>
55 #include <linux/iopoll.h>
56 #include <linux/module.h>
57 #include <linux/pci.h>
58 #include <linux/security.h>
59 #include <linux/sizes.h>
60 #include <linux/string_helpers.h>
61 
62 #include "vsec.h"
63 
64 /**
65  * struct intel_tpmi_pfs_entry - TPMI PM Feature Structure (PFS) entry
66  * @tpmi_id:	TPMI feature identifier (what the feature is and its data format).
67  * @num_entries: Number of feature interface instances present in the PFS.
68  *		 This represents the maximum number of Power domains in the SoC.
69  * @entry_size:	Interface instance entry size in 32-bit words.
70  * @cap_offset:	Offset from the PM_Features base address to the base of the PM VSEC
71  *		register bank in KB.
72  * @attribute:	Feature attribute: 0=BIOS. 1=OS. 2-3=Reserved.
73  * @reserved:	Bits for use in the future.
74  *
75  * Represents one TPMI feature entry data in the PFS retrieved as is
76  * from the hardware.
77  */
78 struct intel_tpmi_pfs_entry {
79 	u64 tpmi_id:8;
80 	u64 num_entries:8;
81 	u64 entry_size:16;
82 	u64 cap_offset:16;
83 	u64 attribute:2;
84 	u64 reserved:14;
85 } __packed;
86 
87 /**
88  * struct intel_tpmi_pm_feature - TPMI PM Feature information for a TPMI ID
89  * @pfs_header:	PFS header retireved from the hardware.
90  * @vsec_offset: Starting MMIO address for this feature in bytes. Essentially
91  *		 this offset = "Address" from VSEC header + PFS Capability
92  *		 offset for this feature entry.
93  * @vsec_dev:	Pointer to intel_vsec_device structure for this TPMI device
94  *
95  * Represents TPMI instance information for one TPMI ID.
96  */
97 struct intel_tpmi_pm_feature {
98 	struct intel_tpmi_pfs_entry pfs_header;
99 	unsigned int vsec_offset;
100 	struct intel_vsec_device *vsec_dev;
101 };
102 
103 /**
104  * struct intel_tpmi_info - TPMI information for all IDs in an instance
105  * @tpmi_features:	Pointer to a list of TPMI feature instances
106  * @vsec_dev:		Pointer to intel_vsec_device structure for this TPMI device
107  * @feature_count:	Number of TPMI of TPMI instances pointed by tpmi_features
108  * @pfs_start:		Start of PFS offset for the TPMI instances in this device
109  * @plat_info:		Stores platform info which can be used by the client drivers
110  * @tpmi_control_mem:	Memory mapped IO for getting control information
111  * @dbgfs_dir:		debugfs entry pointer
112  *
113  * Stores the information for all TPMI devices enumerated from a single PCI device.
114  */
115 struct intel_tpmi_info {
116 	struct intel_tpmi_pm_feature *tpmi_features;
117 	struct intel_vsec_device *vsec_dev;
118 	int feature_count;
119 	u64 pfs_start;
120 	struct intel_tpmi_plat_info plat_info;
121 	void __iomem *tpmi_control_mem;
122 	struct dentry *dbgfs_dir;
123 };
124 
125 /**
126  * struct tpmi_info_header - CPU package ID to PCI device mapping information
127  * @fn:		PCI function number
128  * @dev:	PCI device number
129  * @bus:	PCI bus number
130  * @pkg:	CPU Package id
131  * @reserved:	Reserved for future use
132  * @lock:	When set to 1 the register is locked and becomes read-only
133  *		until next reset. Not for use by the OS driver.
134  *
135  * The structure to read hardware provided mapping information.
136  */
137 struct tpmi_info_header {
138 	u64 fn:3;
139 	u64 dev:5;
140 	u64 bus:8;
141 	u64 pkg:8;
142 	u64 reserved:39;
143 	u64 lock:1;
144 } __packed;
145 
146 /**
147  * struct tpmi_feature_state - Structure to read hardware state of a feature
148  * @enabled:	Enable state of a feature, 1: enabled, 0: disabled
149  * @reserved_1:	Reserved for future use
150  * @write_blocked: Writes are blocked means all write operations are ignored
151  * @read_blocked: Reads are blocked means will read 0xFFs
152  * @pcs_select:	Interface used by out of band software, not used in OS
153  * @reserved_2:	Reserved for future use
154  * @id:		TPMI ID of the feature
155  * @reserved_3:	Reserved for future use
156  * @locked:	When set to 1, OS can't change this register.
157  *
158  * The structure is used to read hardware state of a TPMI feature. This
159  * information is used for debug and restricting operations for this feature.
160  */
161 struct tpmi_feature_state {
162 	u32 enabled:1;
163 	u32 reserved_1:3;
164 	u32 write_blocked:1;
165 	u32 read_blocked:1;
166 	u32 pcs_select:1;
167 	u32 reserved_2:1;
168 	u32 id:8;
169 	u32 reserved_3:15;
170 	u32 locked:1;
171 } __packed;
172 
173 /*
174  * The size from hardware is in u32 units. This size is from a trusted hardware,
175  * but better to verify for pre silicon platforms. Set size to 0, when invalid.
176  */
177 #define TPMI_GET_SINGLE_ENTRY_SIZE(pfs)							\
178 ({											\
179 	pfs->pfs_header.entry_size > SZ_1K ? 0 : pfs->pfs_header.entry_size << 2;	\
180 })
181 
182 /* Used during auxbus device creation */
183 static DEFINE_IDA(intel_vsec_tpmi_ida);
184 
185 struct intel_tpmi_plat_info *tpmi_get_platform_data(struct auxiliary_device *auxdev)
186 {
187 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
188 
189 	return vsec_dev->priv_data;
190 }
191 EXPORT_SYMBOL_NS_GPL(tpmi_get_platform_data, INTEL_TPMI);
192 
193 int tpmi_get_resource_count(struct auxiliary_device *auxdev)
194 {
195 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
196 
197 	if (vsec_dev)
198 		return vsec_dev->num_resources;
199 
200 	return 0;
201 }
202 EXPORT_SYMBOL_NS_GPL(tpmi_get_resource_count, INTEL_TPMI);
203 
204 struct resource *tpmi_get_resource_at_index(struct auxiliary_device *auxdev, int index)
205 {
206 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
207 
208 	if (vsec_dev && index < vsec_dev->num_resources)
209 		return &vsec_dev->resource[index];
210 
211 	return NULL;
212 }
213 EXPORT_SYMBOL_NS_GPL(tpmi_get_resource_at_index, INTEL_TPMI);
214 
215 /* TPMI Control Interface */
216 
217 #define TPMI_CONTROL_STATUS_OFFSET	0x00
218 #define TPMI_COMMAND_OFFSET		0x08
219 #define TMPI_CONTROL_DATA_VAL_OFFSET	0x0c
220 
221 /*
222  * Spec is calling for max 1 seconds to get ownership at the worst
223  * case. Read at 10 ms timeouts and repeat up to 1 second.
224  */
225 #define TPMI_CONTROL_TIMEOUT_US		(10 * USEC_PER_MSEC)
226 #define TPMI_CONTROL_TIMEOUT_MAX_US	(1 * USEC_PER_SEC)
227 
228 #define TPMI_RB_TIMEOUT_US		(10 * USEC_PER_MSEC)
229 #define TPMI_RB_TIMEOUT_MAX_US		USEC_PER_SEC
230 
231 /* TPMI Control status register defines */
232 
233 #define TPMI_CONTROL_STATUS_RB		BIT_ULL(0)
234 
235 #define TPMI_CONTROL_STATUS_OWNER	GENMASK_ULL(5, 4)
236 #define TPMI_OWNER_NONE			0
237 #define TPMI_OWNER_IN_BAND		1
238 
239 #define TPMI_CONTROL_STATUS_CPL		BIT_ULL(6)
240 #define TPMI_CONTROL_STATUS_RESULT	GENMASK_ULL(15, 8)
241 #define TPMI_CONTROL_STATUS_LEN		GENMASK_ULL(31, 16)
242 
243 #define TPMI_CMD_PKT_LEN		2
244 #define TPMI_CMD_STATUS_SUCCESS		0x40
245 
246 /* TPMI command data registers */
247 #define TMPI_CONTROL_DATA_CMD		GENMASK_ULL(7, 0)
248 #define TPMI_CONTROL_DATA_VAL_FEATURE	GENMASK_ULL(48, 40)
249 
250 /* Command to send via control interface */
251 #define TPMI_CONTROL_GET_STATE_CMD	0x10
252 
253 #define TPMI_CONTROL_CMD_MASK		GENMASK_ULL(48, 40)
254 
255 #define TPMI_CMD_LEN_MASK		GENMASK_ULL(18, 16)
256 
257 /* Mutex to complete get feature status without interruption */
258 static DEFINE_MUTEX(tpmi_dev_lock);
259 
260 static int tpmi_wait_for_owner(struct intel_tpmi_info *tpmi_info, u8 owner)
261 {
262 	u64 control;
263 
264 	return readq_poll_timeout(tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET,
265 				  control, owner == FIELD_GET(TPMI_CONTROL_STATUS_OWNER, control),
266 				  TPMI_CONTROL_TIMEOUT_US, TPMI_CONTROL_TIMEOUT_MAX_US);
267 }
268 
269 static int tpmi_read_feature_status(struct intel_tpmi_info *tpmi_info, int feature_id,
270 				    struct tpmi_feature_state *feature_state)
271 {
272 	u64 control, data;
273 	int ret;
274 
275 	if (!tpmi_info->tpmi_control_mem)
276 		return -EFAULT;
277 
278 	mutex_lock(&tpmi_dev_lock);
279 
280 	/* Wait for owner bit set to 0 (none) */
281 	ret = tpmi_wait_for_owner(tpmi_info, TPMI_OWNER_NONE);
282 	if (ret)
283 		goto err_unlock;
284 
285 	/* set command id to 0x10 for TPMI_GET_STATE */
286 	data = FIELD_PREP(TMPI_CONTROL_DATA_CMD, TPMI_CONTROL_GET_STATE_CMD);
287 
288 	/* 32 bits for DATA offset and +8 for feature_id field */
289 	data |= FIELD_PREP(TPMI_CONTROL_DATA_VAL_FEATURE, feature_id);
290 
291 	/* Write at command offset for qword access */
292 	writeq(data, tpmi_info->tpmi_control_mem + TPMI_COMMAND_OFFSET);
293 
294 	/* Wait for owner bit set to in-band */
295 	ret = tpmi_wait_for_owner(tpmi_info, TPMI_OWNER_IN_BAND);
296 	if (ret)
297 		goto err_unlock;
298 
299 	/* Set Run Busy and packet length of 2 dwords */
300 	control = TPMI_CONTROL_STATUS_RB;
301 	control |= FIELD_PREP(TPMI_CONTROL_STATUS_LEN, TPMI_CMD_PKT_LEN);
302 
303 	/* Write at status offset for qword access */
304 	writeq(control, tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET);
305 
306 	/* Wait for Run Busy clear */
307 	ret = readq_poll_timeout(tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET,
308 				 control, !(control & TPMI_CONTROL_STATUS_RB),
309 				 TPMI_RB_TIMEOUT_US, TPMI_RB_TIMEOUT_MAX_US);
310 	if (ret)
311 		goto done_proc;
312 
313 	control = FIELD_GET(TPMI_CONTROL_STATUS_RESULT, control);
314 	if (control != TPMI_CMD_STATUS_SUCCESS) {
315 		ret = -EBUSY;
316 		goto done_proc;
317 	}
318 
319 	/* Response is ready */
320 	memcpy_fromio(feature_state, tpmi_info->tpmi_control_mem + TMPI_CONTROL_DATA_VAL_OFFSET,
321 		      sizeof(*feature_state));
322 
323 	ret = 0;
324 
325 done_proc:
326 	/* Set CPL "completion" bit */
327 	writeq(TPMI_CONTROL_STATUS_CPL, tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET);
328 
329 err_unlock:
330 	mutex_unlock(&tpmi_dev_lock);
331 
332 	return ret;
333 }
334 
335 int tpmi_get_feature_status(struct auxiliary_device *auxdev,
336 			    int feature_id, bool *read_blocked, bool *write_blocked)
337 {
338 	struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(auxdev->dev.parent);
339 	struct intel_tpmi_info *tpmi_info = auxiliary_get_drvdata(&intel_vsec_dev->auxdev);
340 	struct tpmi_feature_state feature_state;
341 	int ret;
342 
343 	ret = tpmi_read_feature_status(tpmi_info, feature_id, &feature_state);
344 	if (ret)
345 		return ret;
346 
347 	*read_blocked = feature_state.read_blocked;
348 	*write_blocked = feature_state.write_blocked;
349 
350 	return 0;
351 }
352 EXPORT_SYMBOL_NS_GPL(tpmi_get_feature_status, INTEL_TPMI);
353 
354 static int tpmi_pfs_dbg_show(struct seq_file *s, void *unused)
355 {
356 	struct intel_tpmi_info *tpmi_info = s->private;
357 	int locked, disabled, read_blocked, write_blocked;
358 	struct tpmi_feature_state feature_state;
359 	struct intel_tpmi_pm_feature *pfs;
360 	int ret, i;
361 
362 
363 	seq_printf(s, "tpmi PFS start offset 0x:%llx\n", tpmi_info->pfs_start);
364 	seq_puts(s, "tpmi_id\t\tentries\t\tsize\t\tcap_offset\tattribute\tvsec_offset\tlocked\tdisabled\tread_blocked\twrite_blocked\n");
365 	for (i = 0; i < tpmi_info->feature_count; ++i) {
366 		pfs = &tpmi_info->tpmi_features[i];
367 		ret = tpmi_read_feature_status(tpmi_info, pfs->pfs_header.tpmi_id, &feature_state);
368 		if (ret) {
369 			locked = 'U';
370 			disabled = 'U';
371 			read_blocked = 'U';
372 			write_blocked = 'U';
373 		} else {
374 			disabled = feature_state.enabled ? 'N' : 'Y';
375 			locked = feature_state.locked ? 'Y' : 'N';
376 			read_blocked = feature_state.read_blocked ? 'Y' : 'N';
377 			write_blocked = feature_state.write_blocked ? 'Y' : 'N';
378 		}
379 		seq_printf(s, "0x%02x\t\t0x%02x\t\t0x%04x\t\t0x%04x\t\t0x%02x\t\t0x%08x\t%c\t%c\t\t%c\t\t%c\n",
380 			   pfs->pfs_header.tpmi_id, pfs->pfs_header.num_entries,
381 			   pfs->pfs_header.entry_size, pfs->pfs_header.cap_offset,
382 			   pfs->pfs_header.attribute, pfs->vsec_offset, locked, disabled,
383 			   read_blocked, write_blocked);
384 	}
385 
386 	return 0;
387 }
388 DEFINE_SHOW_ATTRIBUTE(tpmi_pfs_dbg);
389 
390 #define MEM_DUMP_COLUMN_COUNT	8
391 
392 static int tpmi_mem_dump_show(struct seq_file *s, void *unused)
393 {
394 	size_t row_size = MEM_DUMP_COLUMN_COUNT * sizeof(u32);
395 	struct intel_tpmi_pm_feature *pfs = s->private;
396 	int count, ret = 0;
397 	void __iomem *mem;
398 	u32 off, size;
399 	u8 *buffer;
400 
401 	size = TPMI_GET_SINGLE_ENTRY_SIZE(pfs);
402 	if (!size)
403 		return -EIO;
404 
405 	buffer = kmalloc(size, GFP_KERNEL);
406 	if (!buffer)
407 		return -ENOMEM;
408 
409 	off = pfs->vsec_offset;
410 
411 	mutex_lock(&tpmi_dev_lock);
412 
413 	for (count = 0; count < pfs->pfs_header.num_entries; ++count) {
414 		seq_printf(s, "TPMI Instance:%d offset:0x%x\n", count, off);
415 
416 		mem = ioremap(off, size);
417 		if (!mem) {
418 			ret = -ENOMEM;
419 			break;
420 		}
421 
422 		memcpy_fromio(buffer, mem, size);
423 
424 		seq_hex_dump(s, " ", DUMP_PREFIX_OFFSET, row_size, sizeof(u32), buffer, size,
425 			     false);
426 
427 		iounmap(mem);
428 
429 		off += size;
430 	}
431 
432 	mutex_unlock(&tpmi_dev_lock);
433 
434 	kfree(buffer);
435 
436 	return ret;
437 }
438 DEFINE_SHOW_ATTRIBUTE(tpmi_mem_dump);
439 
440 static ssize_t mem_write(struct file *file, const char __user *userbuf, size_t len, loff_t *ppos)
441 {
442 	struct seq_file *m = file->private_data;
443 	struct intel_tpmi_pm_feature *pfs = m->private;
444 	u32 addr, value, punit, size;
445 	u32 num_elems, *array;
446 	void __iomem *mem;
447 	int ret;
448 
449 	size = TPMI_GET_SINGLE_ENTRY_SIZE(pfs);
450 	if (!size)
451 		return -EIO;
452 
453 	ret = parse_int_array_user(userbuf, len, (int **)&array);
454 	if (ret < 0)
455 		return ret;
456 
457 	num_elems = *array;
458 	if (num_elems != 3) {
459 		ret = -EINVAL;
460 		goto exit_write;
461 	}
462 
463 	punit = array[1];
464 	addr = array[2];
465 	value = array[3];
466 
467 	if (punit >= pfs->pfs_header.num_entries) {
468 		ret = -EINVAL;
469 		goto exit_write;
470 	}
471 
472 	if (addr >= size) {
473 		ret = -EINVAL;
474 		goto exit_write;
475 	}
476 
477 	mutex_lock(&tpmi_dev_lock);
478 
479 	mem = ioremap(pfs->vsec_offset + punit * size, size);
480 	if (!mem) {
481 		ret = -ENOMEM;
482 		goto unlock_mem_write;
483 	}
484 
485 	writel(value, mem + addr);
486 
487 	iounmap(mem);
488 
489 	ret = len;
490 
491 unlock_mem_write:
492 	mutex_unlock(&tpmi_dev_lock);
493 
494 exit_write:
495 	kfree(array);
496 
497 	return ret;
498 }
499 
500 static int mem_write_show(struct seq_file *s, void *unused)
501 {
502 	return 0;
503 }
504 
505 static int mem_write_open(struct inode *inode, struct file *file)
506 {
507 	return single_open(file, mem_write_show, inode->i_private);
508 }
509 
510 static const struct file_operations mem_write_ops = {
511 	.open           = mem_write_open,
512 	.read           = seq_read,
513 	.write          = mem_write,
514 	.llseek         = seq_lseek,
515 	.release        = single_release,
516 };
517 
518 #define tpmi_to_dev(info)	(&info->vsec_dev->pcidev->dev)
519 
520 static void tpmi_dbgfs_register(struct intel_tpmi_info *tpmi_info)
521 {
522 	char name[64];
523 	int i;
524 
525 	snprintf(name, sizeof(name), "tpmi-%s", dev_name(tpmi_to_dev(tpmi_info)));
526 	tpmi_info->dbgfs_dir = debugfs_create_dir(name, NULL);
527 
528 	debugfs_create_file("pfs_dump", 0444, tpmi_info->dbgfs_dir, tpmi_info, &tpmi_pfs_dbg_fops);
529 
530 	for (i = 0; i < tpmi_info->feature_count; ++i) {
531 		struct intel_tpmi_pm_feature *pfs;
532 		struct dentry *dir;
533 
534 		pfs = &tpmi_info->tpmi_features[i];
535 		snprintf(name, sizeof(name), "tpmi-id-%02x", pfs->pfs_header.tpmi_id);
536 		dir = debugfs_create_dir(name, tpmi_info->dbgfs_dir);
537 
538 		debugfs_create_file("mem_dump", 0444, dir, pfs, &tpmi_mem_dump_fops);
539 		debugfs_create_file("mem_write", 0644, dir, pfs, &mem_write_ops);
540 	}
541 }
542 
543 static void tpmi_set_control_base(struct auxiliary_device *auxdev,
544 				  struct intel_tpmi_info *tpmi_info,
545 				  struct intel_tpmi_pm_feature *pfs)
546 {
547 	void __iomem *mem;
548 	u32 size;
549 
550 	size = TPMI_GET_SINGLE_ENTRY_SIZE(pfs);
551 	if (!size)
552 		return;
553 
554 	mem = devm_ioremap(&auxdev->dev, pfs->vsec_offset, size);
555 	if (!mem)
556 		return;
557 
558 	/* mem is pointing to TPMI CONTROL base */
559 	tpmi_info->tpmi_control_mem = mem;
560 }
561 
562 static const char *intel_tpmi_name(enum intel_tpmi_id id)
563 {
564 	switch (id) {
565 	case TPMI_ID_RAPL:
566 		return "rapl";
567 	case TPMI_ID_PEM:
568 		return "pem";
569 	case TPMI_ID_UNCORE:
570 		return "uncore";
571 	case TPMI_ID_SST:
572 		return "sst";
573 	default:
574 		return NULL;
575 	}
576 }
577 
578 /* String Length for tpmi-"feature_name(upto 8 bytes)" */
579 #define TPMI_FEATURE_NAME_LEN	14
580 
581 static int tpmi_create_device(struct intel_tpmi_info *tpmi_info,
582 			      struct intel_tpmi_pm_feature *pfs,
583 			      u64 pfs_start)
584 {
585 	struct intel_vsec_device *vsec_dev = tpmi_info->vsec_dev;
586 	char feature_id_name[TPMI_FEATURE_NAME_LEN];
587 	struct intel_vsec_device *feature_vsec_dev;
588 	struct tpmi_feature_state feature_state;
589 	struct resource *res, *tmp;
590 	const char *name;
591 	int i, ret;
592 
593 	ret = tpmi_read_feature_status(tpmi_info, pfs->pfs_header.tpmi_id, &feature_state);
594 	if (ret)
595 		return ret;
596 
597 	/*
598 	 * If not enabled, continue to look at other features in the PFS, so return -EOPNOTSUPP.
599 	 * This will not cause failure of loading of this driver.
600 	 */
601 	if (!feature_state.enabled)
602 		return -EOPNOTSUPP;
603 
604 	name = intel_tpmi_name(pfs->pfs_header.tpmi_id);
605 	if (!name)
606 		return -EOPNOTSUPP;
607 
608 	res = kcalloc(pfs->pfs_header.num_entries, sizeof(*res), GFP_KERNEL);
609 	if (!res)
610 		return -ENOMEM;
611 
612 	feature_vsec_dev = kzalloc(sizeof(*feature_vsec_dev), GFP_KERNEL);
613 	if (!feature_vsec_dev) {
614 		kfree(res);
615 		return -ENOMEM;
616 	}
617 
618 	snprintf(feature_id_name, sizeof(feature_id_name), "tpmi-%s", name);
619 
620 	for (i = 0, tmp = res; i < pfs->pfs_header.num_entries; i++, tmp++) {
621 		u64 entry_size_bytes = pfs->pfs_header.entry_size * sizeof(u32);
622 
623 		tmp->start = pfs->vsec_offset + entry_size_bytes * i;
624 		tmp->end = tmp->start + entry_size_bytes - 1;
625 		tmp->flags = IORESOURCE_MEM;
626 	}
627 
628 	feature_vsec_dev->pcidev = vsec_dev->pcidev;
629 	feature_vsec_dev->resource = res;
630 	feature_vsec_dev->num_resources = pfs->pfs_header.num_entries;
631 	feature_vsec_dev->priv_data = &tpmi_info->plat_info;
632 	feature_vsec_dev->priv_data_size = sizeof(tpmi_info->plat_info);
633 	feature_vsec_dev->ida = &intel_vsec_tpmi_ida;
634 
635 	/*
636 	 * intel_vsec_add_aux() is resource managed, no explicit
637 	 * delete is required on error or on module unload.
638 	 * feature_vsec_dev and res memory are also freed as part of
639 	 * device deletion.
640 	 */
641 	return intel_vsec_add_aux(vsec_dev->pcidev, &vsec_dev->auxdev.dev,
642 				  feature_vsec_dev, feature_id_name);
643 }
644 
645 static int tpmi_create_devices(struct intel_tpmi_info *tpmi_info)
646 {
647 	struct intel_vsec_device *vsec_dev = tpmi_info->vsec_dev;
648 	int ret, i;
649 
650 	for (i = 0; i < vsec_dev->num_resources; i++) {
651 		ret = tpmi_create_device(tpmi_info, &tpmi_info->tpmi_features[i],
652 					 tpmi_info->pfs_start);
653 		/*
654 		 * Fail, if the supported features fails to create device,
655 		 * otherwise, continue. Even if one device failed to create,
656 		 * fail the loading of driver. Since intel_vsec_add_aux()
657 		 * is resource managed, no clean up is required for the
658 		 * successfully created devices.
659 		 */
660 		if (ret && ret != -EOPNOTSUPP)
661 			return ret;
662 	}
663 
664 	return 0;
665 }
666 
667 #define TPMI_INFO_BUS_INFO_OFFSET	0x08
668 
669 static int tpmi_process_info(struct intel_tpmi_info *tpmi_info,
670 			     struct intel_tpmi_pm_feature *pfs)
671 {
672 	struct tpmi_info_header header;
673 	void __iomem *info_mem;
674 
675 	info_mem = ioremap(pfs->vsec_offset + TPMI_INFO_BUS_INFO_OFFSET,
676 			   pfs->pfs_header.entry_size * sizeof(u32) - TPMI_INFO_BUS_INFO_OFFSET);
677 	if (!info_mem)
678 		return -ENOMEM;
679 
680 	memcpy_fromio(&header, info_mem, sizeof(header));
681 
682 	tpmi_info->plat_info.package_id = header.pkg;
683 	tpmi_info->plat_info.bus_number = header.bus;
684 	tpmi_info->plat_info.device_number = header.dev;
685 	tpmi_info->plat_info.function_number = header.fn;
686 
687 	iounmap(info_mem);
688 
689 	return 0;
690 }
691 
692 static int tpmi_fetch_pfs_header(struct intel_tpmi_pm_feature *pfs, u64 start, int size)
693 {
694 	void __iomem *pfs_mem;
695 
696 	pfs_mem = ioremap(start, size);
697 	if (!pfs_mem)
698 		return -ENOMEM;
699 
700 	memcpy_fromio(&pfs->pfs_header, pfs_mem, sizeof(pfs->pfs_header));
701 
702 	iounmap(pfs_mem);
703 
704 	return 0;
705 }
706 
707 #define TPMI_CAP_OFFSET_UNIT	1024
708 
709 static int intel_vsec_tpmi_init(struct auxiliary_device *auxdev)
710 {
711 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
712 	struct pci_dev *pci_dev = vsec_dev->pcidev;
713 	struct intel_tpmi_info *tpmi_info;
714 	u64 pfs_start = 0;
715 	int ret, i;
716 
717 	tpmi_info = devm_kzalloc(&auxdev->dev, sizeof(*tpmi_info), GFP_KERNEL);
718 	if (!tpmi_info)
719 		return -ENOMEM;
720 
721 	tpmi_info->vsec_dev = vsec_dev;
722 	tpmi_info->feature_count = vsec_dev->num_resources;
723 	tpmi_info->plat_info.bus_number = pci_dev->bus->number;
724 
725 	tpmi_info->tpmi_features = devm_kcalloc(&auxdev->dev, vsec_dev->num_resources,
726 						sizeof(*tpmi_info->tpmi_features),
727 						GFP_KERNEL);
728 	if (!tpmi_info->tpmi_features)
729 		return -ENOMEM;
730 
731 	for (i = 0; i < vsec_dev->num_resources; i++) {
732 		struct intel_tpmi_pm_feature *pfs;
733 		struct resource *res;
734 		u64 res_start;
735 		int size, ret;
736 
737 		pfs = &tpmi_info->tpmi_features[i];
738 		pfs->vsec_dev = vsec_dev;
739 
740 		res = &vsec_dev->resource[i];
741 		if (!res)
742 			continue;
743 
744 		res_start = res->start;
745 		size = resource_size(res);
746 		if (size < 0)
747 			continue;
748 
749 		ret = tpmi_fetch_pfs_header(pfs, res_start, size);
750 		if (ret)
751 			continue;
752 
753 		if (!pfs_start)
754 			pfs_start = res_start;
755 
756 		pfs->vsec_offset = pfs_start + pfs->pfs_header.cap_offset * TPMI_CAP_OFFSET_UNIT;
757 
758 		/*
759 		 * Process TPMI_INFO to get PCI device to CPU package ID.
760 		 * Device nodes for TPMI features are not created in this
761 		 * for loop. So, the mapping information will be available
762 		 * when actual device nodes created outside this
763 		 * loop via tpmi_create_devices().
764 		 */
765 		if (pfs->pfs_header.tpmi_id == TPMI_INFO_ID)
766 			tpmi_process_info(tpmi_info, pfs);
767 
768 		if (pfs->pfs_header.tpmi_id == TPMI_CONTROL_ID)
769 			tpmi_set_control_base(auxdev, tpmi_info, pfs);
770 	}
771 
772 	tpmi_info->pfs_start = pfs_start;
773 
774 	auxiliary_set_drvdata(auxdev, tpmi_info);
775 
776 	ret = tpmi_create_devices(tpmi_info);
777 	if (ret)
778 		return ret;
779 
780 	/*
781 	 * Allow debugfs when security policy allows. Everything this debugfs
782 	 * interface provides, can also be done via /dev/mem access. If
783 	 * /dev/mem interface is locked, don't allow debugfs to present any
784 	 * information. Also check for CAP_SYS_RAWIO as /dev/mem interface.
785 	 */
786 	if (!security_locked_down(LOCKDOWN_DEV_MEM) && capable(CAP_SYS_RAWIO))
787 		tpmi_dbgfs_register(tpmi_info);
788 
789 	return 0;
790 }
791 
792 static int tpmi_probe(struct auxiliary_device *auxdev,
793 		      const struct auxiliary_device_id *id)
794 {
795 	return intel_vsec_tpmi_init(auxdev);
796 }
797 
798 static void tpmi_remove(struct auxiliary_device *auxdev)
799 {
800 	struct intel_tpmi_info *tpmi_info = auxiliary_get_drvdata(auxdev);
801 
802 	debugfs_remove_recursive(tpmi_info->dbgfs_dir);
803 }
804 
805 static const struct auxiliary_device_id tpmi_id_table[] = {
806 	{ .name = "intel_vsec.tpmi" },
807 	{}
808 };
809 MODULE_DEVICE_TABLE(auxiliary, tpmi_id_table);
810 
811 static struct auxiliary_driver tpmi_aux_driver = {
812 	.id_table	= tpmi_id_table,
813 	.probe		= tpmi_probe,
814 	.remove         = tpmi_remove,
815 };
816 
817 module_auxiliary_driver(tpmi_aux_driver);
818 
819 MODULE_IMPORT_NS(INTEL_VSEC);
820 MODULE_DESCRIPTION("Intel TPMI enumeration module");
821 MODULE_LICENSE("GPL");
822