xref: /linux/drivers/platform/x86/intel/tpmi.c (revision d642ef71)
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  * List of supported TMPI IDs.
175  * Some TMPI IDs are not used by Linux, so the numbers are not consecutive.
176  */
177 enum intel_tpmi_id {
178 	TPMI_ID_RAPL = 0, /* Running Average Power Limit */
179 	TPMI_ID_PEM = 1, /* Power and Perf excursion Monitor */
180 	TPMI_ID_UNCORE = 2, /* Uncore Frequency Scaling */
181 	TPMI_ID_SST = 5, /* Speed Select Technology */
182 	TPMI_CONTROL_ID = 0x80, /* Special ID for getting feature status */
183 	TPMI_INFO_ID = 0x81, /* Special ID for PCI BDF and Package ID information */
184 };
185 
186 /*
187  * The size from hardware is in u32 units. This size is from a trusted hardware,
188  * but better to verify for pre silicon platforms. Set size to 0, when invalid.
189  */
190 #define TPMI_GET_SINGLE_ENTRY_SIZE(pfs)							\
191 ({											\
192 	pfs->pfs_header.entry_size > SZ_1K ? 0 : pfs->pfs_header.entry_size << 2;	\
193 })
194 
195 /* Used during auxbus device creation */
196 static DEFINE_IDA(intel_vsec_tpmi_ida);
197 
198 struct intel_tpmi_plat_info *tpmi_get_platform_data(struct auxiliary_device *auxdev)
199 {
200 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
201 
202 	return vsec_dev->priv_data;
203 }
204 EXPORT_SYMBOL_NS_GPL(tpmi_get_platform_data, INTEL_TPMI);
205 
206 int tpmi_get_resource_count(struct auxiliary_device *auxdev)
207 {
208 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
209 
210 	if (vsec_dev)
211 		return vsec_dev->num_resources;
212 
213 	return 0;
214 }
215 EXPORT_SYMBOL_NS_GPL(tpmi_get_resource_count, INTEL_TPMI);
216 
217 struct resource *tpmi_get_resource_at_index(struct auxiliary_device *auxdev, int index)
218 {
219 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
220 
221 	if (vsec_dev && index < vsec_dev->num_resources)
222 		return &vsec_dev->resource[index];
223 
224 	return NULL;
225 }
226 EXPORT_SYMBOL_NS_GPL(tpmi_get_resource_at_index, INTEL_TPMI);
227 
228 /* TPMI Control Interface */
229 
230 #define TPMI_CONTROL_STATUS_OFFSET	0x00
231 #define TPMI_COMMAND_OFFSET		0x08
232 #define TMPI_CONTROL_DATA_VAL_OFFSET	0x0c
233 
234 /*
235  * Spec is calling for max 1 seconds to get ownership at the worst
236  * case. Read at 10 ms timeouts and repeat up to 1 second.
237  */
238 #define TPMI_CONTROL_TIMEOUT_US		(10 * USEC_PER_MSEC)
239 #define TPMI_CONTROL_TIMEOUT_MAX_US	(1 * USEC_PER_SEC)
240 
241 #define TPMI_RB_TIMEOUT_US		(10 * USEC_PER_MSEC)
242 #define TPMI_RB_TIMEOUT_MAX_US		USEC_PER_SEC
243 
244 /* TPMI Control status register defines */
245 
246 #define TPMI_CONTROL_STATUS_RB		BIT_ULL(0)
247 
248 #define TPMI_CONTROL_STATUS_OWNER	GENMASK_ULL(5, 4)
249 #define TPMI_OWNER_NONE			0
250 #define TPMI_OWNER_IN_BAND		1
251 
252 #define TPMI_CONTROL_STATUS_CPL		BIT_ULL(6)
253 #define TPMI_CONTROL_STATUS_RESULT	GENMASK_ULL(15, 8)
254 #define TPMI_CONTROL_STATUS_LEN		GENMASK_ULL(31, 16)
255 
256 #define TPMI_CMD_PKT_LEN		2
257 #define TPMI_CMD_STATUS_SUCCESS		0x40
258 
259 /* TPMI command data registers */
260 #define TMPI_CONTROL_DATA_CMD		GENMASK_ULL(7, 0)
261 #define TPMI_CONTROL_DATA_VAL_FEATURE	GENMASK_ULL(48, 40)
262 
263 /* Command to send via control interface */
264 #define TPMI_CONTROL_GET_STATE_CMD	0x10
265 
266 #define TPMI_CONTROL_CMD_MASK		GENMASK_ULL(48, 40)
267 
268 #define TPMI_CMD_LEN_MASK		GENMASK_ULL(18, 16)
269 
270 /* Mutex to complete get feature status without interruption */
271 static DEFINE_MUTEX(tpmi_dev_lock);
272 
273 static int tpmi_wait_for_owner(struct intel_tpmi_info *tpmi_info, u8 owner)
274 {
275 	u64 control;
276 
277 	return readq_poll_timeout(tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET,
278 				  control, owner == FIELD_GET(TPMI_CONTROL_STATUS_OWNER, control),
279 				  TPMI_CONTROL_TIMEOUT_US, TPMI_CONTROL_TIMEOUT_MAX_US);
280 }
281 
282 static int tpmi_read_feature_status(struct intel_tpmi_info *tpmi_info, int feature_id,
283 				    struct tpmi_feature_state *feature_state)
284 {
285 	u64 control, data;
286 	int ret;
287 
288 	if (!tpmi_info->tpmi_control_mem)
289 		return -EFAULT;
290 
291 	mutex_lock(&tpmi_dev_lock);
292 
293 	/* Wait for owner bit set to 0 (none) */
294 	ret = tpmi_wait_for_owner(tpmi_info, TPMI_OWNER_NONE);
295 	if (ret)
296 		goto err_unlock;
297 
298 	/* set command id to 0x10 for TPMI_GET_STATE */
299 	data = FIELD_PREP(TMPI_CONTROL_DATA_CMD, TPMI_CONTROL_GET_STATE_CMD);
300 
301 	/* 32 bits for DATA offset and +8 for feature_id field */
302 	data |= FIELD_PREP(TPMI_CONTROL_DATA_VAL_FEATURE, feature_id);
303 
304 	/* Write at command offset for qword access */
305 	writeq(data, tpmi_info->tpmi_control_mem + TPMI_COMMAND_OFFSET);
306 
307 	/* Wait for owner bit set to in-band */
308 	ret = tpmi_wait_for_owner(tpmi_info, TPMI_OWNER_IN_BAND);
309 	if (ret)
310 		goto err_unlock;
311 
312 	/* Set Run Busy and packet length of 2 dwords */
313 	control = TPMI_CONTROL_STATUS_RB;
314 	control |= FIELD_PREP(TPMI_CONTROL_STATUS_LEN, TPMI_CMD_PKT_LEN);
315 
316 	/* Write at status offset for qword access */
317 	writeq(control, tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET);
318 
319 	/* Wait for Run Busy clear */
320 	ret = readq_poll_timeout(tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET,
321 				 control, !(control & TPMI_CONTROL_STATUS_RB),
322 				 TPMI_RB_TIMEOUT_US, TPMI_RB_TIMEOUT_MAX_US);
323 	if (ret)
324 		goto done_proc;
325 
326 	control = FIELD_GET(TPMI_CONTROL_STATUS_RESULT, control);
327 	if (control != TPMI_CMD_STATUS_SUCCESS) {
328 		ret = -EBUSY;
329 		goto done_proc;
330 	}
331 
332 	/* Response is ready */
333 	memcpy_fromio(feature_state, tpmi_info->tpmi_control_mem + TMPI_CONTROL_DATA_VAL_OFFSET,
334 		      sizeof(*feature_state));
335 
336 	ret = 0;
337 
338 done_proc:
339 	/* Set CPL "completion" bit */
340 	writeq(TPMI_CONTROL_STATUS_CPL, tpmi_info->tpmi_control_mem + TPMI_CONTROL_STATUS_OFFSET);
341 
342 err_unlock:
343 	mutex_unlock(&tpmi_dev_lock);
344 
345 	return ret;
346 }
347 
348 int tpmi_get_feature_status(struct auxiliary_device *auxdev, int feature_id,
349 			    int *locked, int *disabled)
350 {
351 	struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(auxdev->dev.parent);
352 	struct intel_tpmi_info *tpmi_info = auxiliary_get_drvdata(&intel_vsec_dev->auxdev);
353 	struct tpmi_feature_state feature_state;
354 	int ret;
355 
356 	ret = tpmi_read_feature_status(tpmi_info, feature_id, &feature_state);
357 	if (ret)
358 		return ret;
359 
360 	*locked = feature_state.locked;
361 	*disabled = !feature_state.enabled;
362 
363 	return 0;
364 }
365 EXPORT_SYMBOL_NS_GPL(tpmi_get_feature_status, INTEL_TPMI);
366 
367 static int tpmi_pfs_dbg_show(struct seq_file *s, void *unused)
368 {
369 	struct intel_tpmi_info *tpmi_info = s->private;
370 	int locked, disabled, read_blocked, write_blocked;
371 	struct tpmi_feature_state feature_state;
372 	struct intel_tpmi_pm_feature *pfs;
373 	int ret, i;
374 
375 
376 	seq_printf(s, "tpmi PFS start offset 0x:%llx\n", tpmi_info->pfs_start);
377 	seq_puts(s, "tpmi_id\t\tentries\t\tsize\t\tcap_offset\tattribute\tvsec_offset\tlocked\tdisabled\tread_blocked\twrite_blocked\n");
378 	for (i = 0; i < tpmi_info->feature_count; ++i) {
379 		pfs = &tpmi_info->tpmi_features[i];
380 		ret = tpmi_read_feature_status(tpmi_info, pfs->pfs_header.tpmi_id, &feature_state);
381 		if (ret) {
382 			locked = 'U';
383 			disabled = 'U';
384 			read_blocked = 'U';
385 			write_blocked = 'U';
386 		} else {
387 			disabled = feature_state.enabled ? 'N' : 'Y';
388 			locked = feature_state.locked ? 'Y' : 'N';
389 			read_blocked = feature_state.read_blocked ? 'Y' : 'N';
390 			write_blocked = feature_state.write_blocked ? 'Y' : 'N';
391 		}
392 		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",
393 			   pfs->pfs_header.tpmi_id, pfs->pfs_header.num_entries,
394 			   pfs->pfs_header.entry_size, pfs->pfs_header.cap_offset,
395 			   pfs->pfs_header.attribute, pfs->vsec_offset, locked, disabled,
396 			   read_blocked, write_blocked);
397 	}
398 
399 	return 0;
400 }
401 DEFINE_SHOW_ATTRIBUTE(tpmi_pfs_dbg);
402 
403 #define MEM_DUMP_COLUMN_COUNT	8
404 
405 static int tpmi_mem_dump_show(struct seq_file *s, void *unused)
406 {
407 	size_t row_size = MEM_DUMP_COLUMN_COUNT * sizeof(u32);
408 	struct intel_tpmi_pm_feature *pfs = s->private;
409 	int count, ret = 0;
410 	void __iomem *mem;
411 	u32 off, size;
412 	u8 *buffer;
413 
414 	size = TPMI_GET_SINGLE_ENTRY_SIZE(pfs);
415 	if (!size)
416 		return -EIO;
417 
418 	buffer = kmalloc(size, GFP_KERNEL);
419 	if (!buffer)
420 		return -ENOMEM;
421 
422 	off = pfs->vsec_offset;
423 
424 	mutex_lock(&tpmi_dev_lock);
425 
426 	for (count = 0; count < pfs->pfs_header.num_entries; ++count) {
427 		seq_printf(s, "TPMI Instance:%d offset:0x%x\n", count, off);
428 
429 		mem = ioremap(off, size);
430 		if (!mem) {
431 			ret = -ENOMEM;
432 			break;
433 		}
434 
435 		memcpy_fromio(buffer, mem, size);
436 
437 		seq_hex_dump(s, " ", DUMP_PREFIX_OFFSET, row_size, sizeof(u32), buffer, size,
438 			     false);
439 
440 		iounmap(mem);
441 
442 		off += size;
443 	}
444 
445 	mutex_unlock(&tpmi_dev_lock);
446 
447 	kfree(buffer);
448 
449 	return ret;
450 }
451 DEFINE_SHOW_ATTRIBUTE(tpmi_mem_dump);
452 
453 static ssize_t mem_write(struct file *file, const char __user *userbuf, size_t len, loff_t *ppos)
454 {
455 	struct seq_file *m = file->private_data;
456 	struct intel_tpmi_pm_feature *pfs = m->private;
457 	u32 addr, value, punit, size;
458 	u32 num_elems, *array;
459 	void __iomem *mem;
460 	int ret;
461 
462 	size = TPMI_GET_SINGLE_ENTRY_SIZE(pfs);
463 	if (!size)
464 		return -EIO;
465 
466 	ret = parse_int_array_user(userbuf, len, (int **)&array);
467 	if (ret < 0)
468 		return ret;
469 
470 	num_elems = *array;
471 	if (num_elems != 3) {
472 		ret = -EINVAL;
473 		goto exit_write;
474 	}
475 
476 	punit = array[1];
477 	addr = array[2];
478 	value = array[3];
479 
480 	if (punit >= pfs->pfs_header.num_entries) {
481 		ret = -EINVAL;
482 		goto exit_write;
483 	}
484 
485 	if (addr >= size) {
486 		ret = -EINVAL;
487 		goto exit_write;
488 	}
489 
490 	mutex_lock(&tpmi_dev_lock);
491 
492 	mem = ioremap(pfs->vsec_offset + punit * size, size);
493 	if (!mem) {
494 		ret = -ENOMEM;
495 		goto unlock_mem_write;
496 	}
497 
498 	writel(value, mem + addr);
499 
500 	iounmap(mem);
501 
502 	ret = len;
503 
504 unlock_mem_write:
505 	mutex_unlock(&tpmi_dev_lock);
506 
507 exit_write:
508 	kfree(array);
509 
510 	return ret;
511 }
512 
513 static int mem_write_show(struct seq_file *s, void *unused)
514 {
515 	return 0;
516 }
517 
518 static int mem_write_open(struct inode *inode, struct file *file)
519 {
520 	return single_open(file, mem_write_show, inode->i_private);
521 }
522 
523 static const struct file_operations mem_write_ops = {
524 	.open           = mem_write_open,
525 	.read           = seq_read,
526 	.write          = mem_write,
527 	.llseek         = seq_lseek,
528 	.release        = single_release,
529 };
530 
531 #define tpmi_to_dev(info)	(&info->vsec_dev->pcidev->dev)
532 
533 static void tpmi_dbgfs_register(struct intel_tpmi_info *tpmi_info)
534 {
535 	char name[64];
536 	int i;
537 
538 	snprintf(name, sizeof(name), "tpmi-%s", dev_name(tpmi_to_dev(tpmi_info)));
539 	tpmi_info->dbgfs_dir = debugfs_create_dir(name, NULL);
540 
541 	debugfs_create_file("pfs_dump", 0444, tpmi_info->dbgfs_dir, tpmi_info, &tpmi_pfs_dbg_fops);
542 
543 	for (i = 0; i < tpmi_info->feature_count; ++i) {
544 		struct intel_tpmi_pm_feature *pfs;
545 		struct dentry *dir;
546 
547 		pfs = &tpmi_info->tpmi_features[i];
548 		snprintf(name, sizeof(name), "tpmi-id-%02x", pfs->pfs_header.tpmi_id);
549 		dir = debugfs_create_dir(name, tpmi_info->dbgfs_dir);
550 
551 		debugfs_create_file("mem_dump", 0444, dir, pfs, &tpmi_mem_dump_fops);
552 		debugfs_create_file("mem_write", 0644, dir, pfs, &mem_write_ops);
553 	}
554 }
555 
556 static void tpmi_set_control_base(struct auxiliary_device *auxdev,
557 				  struct intel_tpmi_info *tpmi_info,
558 				  struct intel_tpmi_pm_feature *pfs)
559 {
560 	void __iomem *mem;
561 	u32 size;
562 
563 	size = TPMI_GET_SINGLE_ENTRY_SIZE(pfs);
564 	if (!size)
565 		return;
566 
567 	mem = devm_ioremap(&auxdev->dev, pfs->vsec_offset, size);
568 	if (!mem)
569 		return;
570 
571 	/* mem is pointing to TPMI CONTROL base */
572 	tpmi_info->tpmi_control_mem = mem;
573 }
574 
575 static const char *intel_tpmi_name(enum intel_tpmi_id id)
576 {
577 	switch (id) {
578 	case TPMI_ID_RAPL:
579 		return "rapl";
580 	case TPMI_ID_PEM:
581 		return "pem";
582 	case TPMI_ID_UNCORE:
583 		return "uncore";
584 	case TPMI_ID_SST:
585 		return "sst";
586 	default:
587 		return NULL;
588 	}
589 }
590 
591 /* String Length for tpmi-"feature_name(upto 8 bytes)" */
592 #define TPMI_FEATURE_NAME_LEN	14
593 
594 static int tpmi_create_device(struct intel_tpmi_info *tpmi_info,
595 			      struct intel_tpmi_pm_feature *pfs,
596 			      u64 pfs_start)
597 {
598 	struct intel_vsec_device *vsec_dev = tpmi_info->vsec_dev;
599 	char feature_id_name[TPMI_FEATURE_NAME_LEN];
600 	struct intel_vsec_device *feature_vsec_dev;
601 	struct resource *res, *tmp;
602 	const char *name;
603 	int i;
604 
605 	name = intel_tpmi_name(pfs->pfs_header.tpmi_id);
606 	if (!name)
607 		return -EOPNOTSUPP;
608 
609 	res = kcalloc(pfs->pfs_header.num_entries, sizeof(*res), GFP_KERNEL);
610 	if (!res)
611 		return -ENOMEM;
612 
613 	feature_vsec_dev = kzalloc(sizeof(*feature_vsec_dev), GFP_KERNEL);
614 	if (!feature_vsec_dev) {
615 		kfree(res);
616 		return -ENOMEM;
617 	}
618 
619 	snprintf(feature_id_name, sizeof(feature_id_name), "tpmi-%s", name);
620 
621 	for (i = 0, tmp = res; i < pfs->pfs_header.num_entries; i++, tmp++) {
622 		u64 entry_size_bytes = pfs->pfs_header.entry_size * sizeof(u32);
623 
624 		tmp->start = pfs->vsec_offset + entry_size_bytes * i;
625 		tmp->end = tmp->start + entry_size_bytes - 1;
626 		tmp->flags = IORESOURCE_MEM;
627 	}
628 
629 	feature_vsec_dev->pcidev = vsec_dev->pcidev;
630 	feature_vsec_dev->resource = res;
631 	feature_vsec_dev->num_resources = pfs->pfs_header.num_entries;
632 	feature_vsec_dev->priv_data = &tpmi_info->plat_info;
633 	feature_vsec_dev->priv_data_size = sizeof(tpmi_info->plat_info);
634 	feature_vsec_dev->ida = &intel_vsec_tpmi_ida;
635 
636 	/*
637 	 * intel_vsec_add_aux() is resource managed, no explicit
638 	 * delete is required on error or on module unload.
639 	 * feature_vsec_dev and res memory are also freed as part of
640 	 * device deletion.
641 	 */
642 	return intel_vsec_add_aux(vsec_dev->pcidev, &vsec_dev->auxdev.dev,
643 				  feature_vsec_dev, feature_id_name);
644 }
645 
646 static int tpmi_create_devices(struct intel_tpmi_info *tpmi_info)
647 {
648 	struct intel_vsec_device *vsec_dev = tpmi_info->vsec_dev;
649 	int ret, i;
650 
651 	for (i = 0; i < vsec_dev->num_resources; i++) {
652 		ret = tpmi_create_device(tpmi_info, &tpmi_info->tpmi_features[i],
653 					 tpmi_info->pfs_start);
654 		/*
655 		 * Fail, if the supported features fails to create device,
656 		 * otherwise, continue. Even if one device failed to create,
657 		 * fail the loading of driver. Since intel_vsec_add_aux()
658 		 * is resource managed, no clean up is required for the
659 		 * successfully created devices.
660 		 */
661 		if (ret && ret != -EOPNOTSUPP)
662 			return ret;
663 	}
664 
665 	return 0;
666 }
667 
668 #define TPMI_INFO_BUS_INFO_OFFSET	0x08
669 
670 static int tpmi_process_info(struct intel_tpmi_info *tpmi_info,
671 			     struct intel_tpmi_pm_feature *pfs)
672 {
673 	struct tpmi_info_header header;
674 	void __iomem *info_mem;
675 
676 	info_mem = ioremap(pfs->vsec_offset + TPMI_INFO_BUS_INFO_OFFSET,
677 			   pfs->pfs_header.entry_size * sizeof(u32) - TPMI_INFO_BUS_INFO_OFFSET);
678 	if (!info_mem)
679 		return -ENOMEM;
680 
681 	memcpy_fromio(&header, info_mem, sizeof(header));
682 
683 	tpmi_info->plat_info.package_id = header.pkg;
684 	tpmi_info->plat_info.bus_number = header.bus;
685 	tpmi_info->plat_info.device_number = header.dev;
686 	tpmi_info->plat_info.function_number = header.fn;
687 
688 	iounmap(info_mem);
689 
690 	return 0;
691 }
692 
693 static int tpmi_fetch_pfs_header(struct intel_tpmi_pm_feature *pfs, u64 start, int size)
694 {
695 	void __iomem *pfs_mem;
696 
697 	pfs_mem = ioremap(start, size);
698 	if (!pfs_mem)
699 		return -ENOMEM;
700 
701 	memcpy_fromio(&pfs->pfs_header, pfs_mem, sizeof(pfs->pfs_header));
702 
703 	iounmap(pfs_mem);
704 
705 	return 0;
706 }
707 
708 #define TPMI_CAP_OFFSET_UNIT	1024
709 
710 static int intel_vsec_tpmi_init(struct auxiliary_device *auxdev)
711 {
712 	struct intel_vsec_device *vsec_dev = auxdev_to_ivdev(auxdev);
713 	struct pci_dev *pci_dev = vsec_dev->pcidev;
714 	struct intel_tpmi_info *tpmi_info;
715 	u64 pfs_start = 0;
716 	int ret, i;
717 
718 	tpmi_info = devm_kzalloc(&auxdev->dev, sizeof(*tpmi_info), GFP_KERNEL);
719 	if (!tpmi_info)
720 		return -ENOMEM;
721 
722 	tpmi_info->vsec_dev = vsec_dev;
723 	tpmi_info->feature_count = vsec_dev->num_resources;
724 	tpmi_info->plat_info.bus_number = pci_dev->bus->number;
725 
726 	tpmi_info->tpmi_features = devm_kcalloc(&auxdev->dev, vsec_dev->num_resources,
727 						sizeof(*tpmi_info->tpmi_features),
728 						GFP_KERNEL);
729 	if (!tpmi_info->tpmi_features)
730 		return -ENOMEM;
731 
732 	for (i = 0; i < vsec_dev->num_resources; i++) {
733 		struct intel_tpmi_pm_feature *pfs;
734 		struct resource *res;
735 		u64 res_start;
736 		int size, ret;
737 
738 		pfs = &tpmi_info->tpmi_features[i];
739 		pfs->vsec_dev = vsec_dev;
740 
741 		res = &vsec_dev->resource[i];
742 		if (!res)
743 			continue;
744 
745 		res_start = res->start;
746 		size = resource_size(res);
747 		if (size < 0)
748 			continue;
749 
750 		ret = tpmi_fetch_pfs_header(pfs, res_start, size);
751 		if (ret)
752 			continue;
753 
754 		if (!pfs_start)
755 			pfs_start = res_start;
756 
757 		pfs->vsec_offset = pfs_start + pfs->pfs_header.cap_offset * TPMI_CAP_OFFSET_UNIT;
758 
759 		/*
760 		 * Process TPMI_INFO to get PCI device to CPU package ID.
761 		 * Device nodes for TPMI features are not created in this
762 		 * for loop. So, the mapping information will be available
763 		 * when actual device nodes created outside this
764 		 * loop via tpmi_create_devices().
765 		 */
766 		if (pfs->pfs_header.tpmi_id == TPMI_INFO_ID)
767 			tpmi_process_info(tpmi_info, pfs);
768 
769 		if (pfs->pfs_header.tpmi_id == TPMI_CONTROL_ID)
770 			tpmi_set_control_base(auxdev, tpmi_info, pfs);
771 	}
772 
773 	tpmi_info->pfs_start = pfs_start;
774 
775 	auxiliary_set_drvdata(auxdev, tpmi_info);
776 
777 	ret = tpmi_create_devices(tpmi_info);
778 	if (ret)
779 		return ret;
780 
781 	/*
782 	 * Allow debugfs when security policy allows. Everything this debugfs
783 	 * interface provides, can also be done via /dev/mem access. If
784 	 * /dev/mem interface is locked, don't allow debugfs to present any
785 	 * information. Also check for CAP_SYS_RAWIO as /dev/mem interface.
786 	 */
787 	if (!security_locked_down(LOCKDOWN_DEV_MEM) && capable(CAP_SYS_RAWIO))
788 		tpmi_dbgfs_register(tpmi_info);
789 
790 	return 0;
791 }
792 
793 static int tpmi_probe(struct auxiliary_device *auxdev,
794 		      const struct auxiliary_device_id *id)
795 {
796 	return intel_vsec_tpmi_init(auxdev);
797 }
798 
799 static void tpmi_remove(struct auxiliary_device *auxdev)
800 {
801 	struct intel_tpmi_info *tpmi_info = auxiliary_get_drvdata(auxdev);
802 
803 	debugfs_remove_recursive(tpmi_info->dbgfs_dir);
804 }
805 
806 static const struct auxiliary_device_id tpmi_id_table[] = {
807 	{ .name = "intel_vsec.tpmi" },
808 	{}
809 };
810 MODULE_DEVICE_TABLE(auxiliary, tpmi_id_table);
811 
812 static struct auxiliary_driver tpmi_aux_driver = {
813 	.id_table	= tpmi_id_table,
814 	.probe		= tpmi_probe,
815 	.remove         = tpmi_remove,
816 };
817 
818 module_auxiliary_driver(tpmi_aux_driver);
819 
820 MODULE_IMPORT_NS(INTEL_VSEC);
821 MODULE_DESCRIPTION("Intel TPMI enumeration module");
822 MODULE_LICENSE("GPL");
823