xref: /linux/drivers/platform/x86/amd/pmf/tee-if.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * AMD Platform Management Framework Driver - TEE Interface
4  *
5  * Copyright (c) 2023, Advanced Micro Devices, Inc.
6  * All Rights Reserved.
7  *
8  * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
9  */
10 
11 #include <linux/debugfs.h>
12 #include <linux/tee_drv.h>
13 #include <linux/uuid.h>
14 #include "pmf.h"
15 
16 #define MAX_TEE_PARAM	4
17 
18 /* Policy binary actions sampling frequency (in ms) */
19 static int pb_actions_ms = MSEC_PER_SEC;
20 /* Sideload policy binaries to debug policy failures */
21 static bool pb_side_load;
22 
23 #ifdef CONFIG_AMD_PMF_DEBUG
24 module_param(pb_actions_ms, int, 0644);
25 MODULE_PARM_DESC(pb_actions_ms, "Policy binary actions sampling frequency (default = 1000ms)");
26 module_param(pb_side_load, bool, 0444);
27 MODULE_PARM_DESC(pb_side_load, "Sideload policy binaries debug policy failures");
28 #endif
29 
30 static const uuid_t amd_pmf_ta_uuid = UUID_INIT(0x6fd93b77, 0x3fb8, 0x524d,
31 						0xb1, 0x2d, 0xc5, 0x29, 0xb1, 0x3d, 0x85, 0x43);
32 
33 static const char *amd_pmf_uevent_as_str(unsigned int state)
34 {
35 	switch (state) {
36 	case SYSTEM_STATE_S0i3:
37 		return "S0i3";
38 	case SYSTEM_STATE_S4:
39 		return "S4";
40 	case SYSTEM_STATE_SCREEN_LOCK:
41 		return "SCREEN_LOCK";
42 	default:
43 		return "Unknown Smart PC event";
44 	}
45 }
46 
47 static void amd_pmf_prepare_args(struct amd_pmf_dev *dev, int cmd,
48 				 struct tee_ioctl_invoke_arg *arg,
49 				 struct tee_param *param)
50 {
51 	memset(arg, 0, sizeof(*arg));
52 	memset(param, 0, MAX_TEE_PARAM * sizeof(*param));
53 
54 	arg->func = cmd;
55 	arg->session = dev->session_id;
56 	arg->num_params = MAX_TEE_PARAM;
57 
58 	/* Fill invoke cmd params */
59 	param[0].u.memref.size = sizeof(struct ta_pmf_shared_memory);
60 	param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT;
61 	param[0].u.memref.shm = dev->fw_shm_pool;
62 	param[0].u.memref.shm_offs = 0;
63 }
64 
65 static void amd_pmf_update_uevents(struct amd_pmf_dev *dev, u16 event)
66 {
67 	input_report_key(dev->pmf_idev, event, 1); /* key press */
68 	input_sync(dev->pmf_idev);
69 	input_report_key(dev->pmf_idev, event, 0); /* key release */
70 	input_sync(dev->pmf_idev);
71 }
72 
73 static void amd_pmf_apply_policies(struct amd_pmf_dev *dev, struct ta_pmf_enact_result *out)
74 {
75 	u32 val;
76 	int idx;
77 
78 	for (idx = 0; idx < out->actions_count; idx++) {
79 		val = out->actions_list[idx].value;
80 		switch (out->actions_list[idx].action_index) {
81 		case PMF_POLICY_SPL:
82 			if (dev->prev_data->spl != val) {
83 				amd_pmf_send_cmd(dev, SET_SPL, false, val, NULL);
84 				dev_dbg(dev->dev, "update SPL: %u\n", val);
85 				dev->prev_data->spl = val;
86 			}
87 			break;
88 
89 		case PMF_POLICY_SPPT:
90 			if (dev->prev_data->sppt != val) {
91 				amd_pmf_send_cmd(dev, SET_SPPT, false, val, NULL);
92 				dev_dbg(dev->dev, "update SPPT: %u\n", val);
93 				dev->prev_data->sppt = val;
94 			}
95 			break;
96 
97 		case PMF_POLICY_FPPT:
98 			if (dev->prev_data->fppt != val) {
99 				amd_pmf_send_cmd(dev, SET_FPPT, false, val, NULL);
100 				dev_dbg(dev->dev, "update FPPT: %u\n", val);
101 				dev->prev_data->fppt = val;
102 			}
103 			break;
104 
105 		case PMF_POLICY_SPPT_APU_ONLY:
106 			if (dev->prev_data->sppt_apuonly != val) {
107 				amd_pmf_send_cmd(dev, SET_SPPT_APU_ONLY, false, val, NULL);
108 				dev_dbg(dev->dev, "update SPPT_APU_ONLY: %u\n", val);
109 				dev->prev_data->sppt_apuonly = val;
110 			}
111 			break;
112 
113 		case PMF_POLICY_STT_MIN:
114 			if (dev->prev_data->stt_minlimit != val) {
115 				amd_pmf_send_cmd(dev, SET_STT_MIN_LIMIT, false, val, NULL);
116 				dev_dbg(dev->dev, "update STT_MIN: %u\n", val);
117 				dev->prev_data->stt_minlimit = val;
118 			}
119 			break;
120 
121 		case PMF_POLICY_STT_SKINTEMP_APU:
122 			if (dev->prev_data->stt_skintemp_apu != val) {
123 				amd_pmf_send_cmd(dev, SET_STT_LIMIT_APU, false, val, NULL);
124 				dev_dbg(dev->dev, "update STT_SKINTEMP_APU: %u\n", val);
125 				dev->prev_data->stt_skintemp_apu = val;
126 			}
127 			break;
128 
129 		case PMF_POLICY_STT_SKINTEMP_HS2:
130 			if (dev->prev_data->stt_skintemp_hs2 != val) {
131 				amd_pmf_send_cmd(dev, SET_STT_LIMIT_HS2, false, val, NULL);
132 				dev_dbg(dev->dev, "update STT_SKINTEMP_HS2: %u\n", val);
133 				dev->prev_data->stt_skintemp_hs2 = val;
134 			}
135 			break;
136 
137 		case PMF_POLICY_P3T:
138 			if (dev->prev_data->p3t_limit != val) {
139 				amd_pmf_send_cmd(dev, SET_P3T, false, val, NULL);
140 				dev_dbg(dev->dev, "update P3T: %u\n", val);
141 				dev->prev_data->p3t_limit = val;
142 			}
143 			break;
144 
145 		case PMF_POLICY_SYSTEM_STATE:
146 			switch (val) {
147 			case 0:
148 				amd_pmf_update_uevents(dev, KEY_SLEEP);
149 				break;
150 			case 1:
151 				amd_pmf_update_uevents(dev, KEY_SUSPEND);
152 				break;
153 			case 2:
154 				amd_pmf_update_uevents(dev, KEY_SCREENLOCK);
155 				break;
156 			default:
157 				dev_err(dev->dev, "Invalid PMF policy system state: %d\n", val);
158 			}
159 
160 			dev_dbg(dev->dev, "update SYSTEM_STATE: %s\n",
161 				amd_pmf_uevent_as_str(val));
162 			break;
163 
164 		case PMF_POLICY_BIOS_OUTPUT_1:
165 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(0), 0);
166 			break;
167 
168 		case PMF_POLICY_BIOS_OUTPUT_2:
169 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(1), 1);
170 			break;
171 
172 		case PMF_POLICY_BIOS_OUTPUT_3:
173 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(2), 2);
174 			break;
175 
176 		case PMF_POLICY_BIOS_OUTPUT_4:
177 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(3), 3);
178 			break;
179 
180 		case PMF_POLICY_BIOS_OUTPUT_5:
181 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(4), 4);
182 			break;
183 
184 		case PMF_POLICY_BIOS_OUTPUT_6:
185 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(5), 5);
186 			break;
187 
188 		case PMF_POLICY_BIOS_OUTPUT_7:
189 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(6), 6);
190 			break;
191 
192 		case PMF_POLICY_BIOS_OUTPUT_8:
193 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(7), 7);
194 			break;
195 
196 		case PMF_POLICY_BIOS_OUTPUT_9:
197 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(8), 8);
198 			break;
199 
200 		case PMF_POLICY_BIOS_OUTPUT_10:
201 			amd_pmf_smartpc_apply_bios_output(dev, val, BIT(9), 9);
202 			break;
203 		}
204 	}
205 }
206 
207 static int amd_pmf_invoke_cmd_enact(struct amd_pmf_dev *dev)
208 {
209 	struct ta_pmf_shared_memory *ta_sm = NULL;
210 	struct ta_pmf_enact_result *out = NULL;
211 	struct ta_pmf_enact_table *in = NULL;
212 	struct tee_param param[MAX_TEE_PARAM];
213 	struct tee_ioctl_invoke_arg arg;
214 	int ret = 0;
215 
216 	if (!dev->tee_ctx)
217 		return -ENODEV;
218 
219 	memset(dev->shbuf, 0, dev->policy_sz);
220 	ta_sm = dev->shbuf;
221 	out = &ta_sm->pmf_output.policy_apply_table;
222 	in = &ta_sm->pmf_input.enact_table;
223 
224 	memset(ta_sm, 0, sizeof(*ta_sm));
225 	ta_sm->command_id = TA_PMF_COMMAND_POLICY_BUILDER_ENACT_POLICIES;
226 	ta_sm->if_version = PMF_TA_IF_VERSION_MAJOR;
227 
228 	amd_pmf_populate_ta_inputs(dev, in);
229 	amd_pmf_prepare_args(dev, TA_PMF_COMMAND_POLICY_BUILDER_ENACT_POLICIES, &arg, param);
230 
231 	ret = tee_client_invoke_func(dev->tee_ctx, &arg, param);
232 	if (ret < 0 || arg.ret != 0) {
233 		dev_err(dev->dev, "TEE enact cmd failed. err: %x, ret:%d\n", arg.ret, ret);
234 		return ret;
235 	}
236 
237 	if (ta_sm->pmf_result == TA_PMF_TYPE_SUCCESS && out->actions_count) {
238 		amd_pmf_dump_ta_inputs(dev, in);
239 		dev_dbg(dev->dev, "action count:%u result:%x\n", out->actions_count,
240 			ta_sm->pmf_result);
241 		amd_pmf_apply_policies(dev, out);
242 	}
243 
244 	return 0;
245 }
246 
247 static int amd_pmf_invoke_cmd_init(struct amd_pmf_dev *dev)
248 {
249 	struct ta_pmf_shared_memory *ta_sm = NULL;
250 	struct tee_param param[MAX_TEE_PARAM];
251 	struct ta_pmf_init_table *in = NULL;
252 	struct tee_ioctl_invoke_arg arg;
253 	int ret = 0;
254 
255 	if (!dev->tee_ctx) {
256 		dev_err(dev->dev, "Failed to get TEE context\n");
257 		return -ENODEV;
258 	}
259 
260 	dev_dbg(dev->dev, "Policy Binary size: %u bytes\n", dev->policy_sz);
261 	memset(dev->shbuf, 0, dev->policy_sz);
262 	ta_sm = dev->shbuf;
263 	in = &ta_sm->pmf_input.init_table;
264 
265 	ta_sm->command_id = TA_PMF_COMMAND_POLICY_BUILDER_INITIALIZE;
266 	ta_sm->if_version = PMF_TA_IF_VERSION_MAJOR;
267 
268 	in->metadata_macrocheck = false;
269 	in->sku_check = false;
270 	in->validate = true;
271 	in->frequency = pb_actions_ms;
272 	in->policies_table.table_size = dev->policy_sz;
273 
274 	memcpy(in->policies_table.table, dev->policy_buf, dev->policy_sz);
275 	amd_pmf_prepare_args(dev, TA_PMF_COMMAND_POLICY_BUILDER_INITIALIZE, &arg, param);
276 
277 	ret = tee_client_invoke_func(dev->tee_ctx, &arg, param);
278 	if (ret < 0 || arg.ret != 0) {
279 		dev_err(dev->dev, "Failed to invoke TEE init cmd. err: %x, ret:%d\n", arg.ret, ret);
280 		return ret;
281 	}
282 
283 	return ta_sm->pmf_result;
284 }
285 
286 static void amd_pmf_invoke_cmd(struct work_struct *work)
287 {
288 	struct amd_pmf_dev *dev = container_of(work, struct amd_pmf_dev, pb_work.work);
289 
290 	amd_pmf_invoke_cmd_enact(dev);
291 	schedule_delayed_work(&dev->pb_work, msecs_to_jiffies(pb_actions_ms));
292 }
293 
294 static int amd_pmf_start_policy_engine(struct amd_pmf_dev *dev)
295 {
296 	struct cookie_header *header;
297 	int res;
298 
299 	if (dev->policy_sz < POLICY_COOKIE_OFFSET + sizeof(*header))
300 		return -EINVAL;
301 
302 	header = (struct cookie_header *)(dev->policy_buf + POLICY_COOKIE_OFFSET);
303 
304 	if (header->sign != POLICY_SIGN_COOKIE || !header->length) {
305 		dev_dbg(dev->dev, "cookie doesn't match\n");
306 		return -EINVAL;
307 	}
308 
309 	if (dev->policy_sz < header->length + 512)
310 		return -EINVAL;
311 
312 	/* Update the actual length */
313 	dev->policy_sz = header->length + 512;
314 	res = amd_pmf_invoke_cmd_init(dev);
315 	if (res == TA_PMF_TYPE_SUCCESS) {
316 		/* Now its safe to announce that smart pc is enabled */
317 		dev->smart_pc_enabled = true;
318 		/*
319 		 * Start collecting the data from TA FW after a small delay
320 		 * or else, we might end up getting stale values.
321 		 */
322 		schedule_delayed_work(&dev->pb_work, msecs_to_jiffies(pb_actions_ms * 3));
323 	} else {
324 		dev_err(dev->dev, "ta invoke cmd init failed err: %x\n", res);
325 		dev->smart_pc_enabled = false;
326 		return -EIO;
327 	}
328 
329 	return 0;
330 }
331 
332 #ifdef CONFIG_AMD_PMF_DEBUG
333 static void amd_pmf_hex_dump_pb(struct amd_pmf_dev *dev)
334 {
335 	print_hex_dump_debug("(pb):  ", DUMP_PREFIX_OFFSET, 16, 1, dev->policy_buf,
336 			     dev->policy_sz, false);
337 }
338 
339 static ssize_t amd_pmf_get_pb_data(struct file *filp, const char __user *buf,
340 				   size_t length, loff_t *pos)
341 {
342 	struct amd_pmf_dev *dev = filp->private_data;
343 	unsigned char *new_policy_buf;
344 	int ret;
345 
346 	/* Policy binary size cannot exceed POLICY_BUF_MAX_SZ */
347 	if (length > POLICY_BUF_MAX_SZ || length == 0)
348 		return -EINVAL;
349 
350 	/* re-alloc to the new buffer length of the policy binary */
351 	new_policy_buf = memdup_user(buf, length);
352 	if (IS_ERR(new_policy_buf))
353 		return PTR_ERR(new_policy_buf);
354 
355 	kfree(dev->policy_buf);
356 	dev->policy_buf = new_policy_buf;
357 	dev->policy_sz = length;
358 
359 	amd_pmf_hex_dump_pb(dev);
360 	ret = amd_pmf_start_policy_engine(dev);
361 	if (ret < 0)
362 		return ret;
363 
364 	return length;
365 }
366 
367 static const struct file_operations pb_fops = {
368 	.write = amd_pmf_get_pb_data,
369 	.open = simple_open,
370 };
371 
372 static void amd_pmf_open_pb(struct amd_pmf_dev *dev, struct dentry *debugfs_root)
373 {
374 	dev->esbin = debugfs_create_dir("pb", debugfs_root);
375 	debugfs_create_file("update_policy", 0644, dev->esbin, dev, &pb_fops);
376 }
377 
378 static void amd_pmf_remove_pb(struct amd_pmf_dev *dev)
379 {
380 	debugfs_remove_recursive(dev->esbin);
381 }
382 #else
383 static void amd_pmf_open_pb(struct amd_pmf_dev *dev, struct dentry *debugfs_root) {}
384 static void amd_pmf_remove_pb(struct amd_pmf_dev *dev) {}
385 static void amd_pmf_hex_dump_pb(struct amd_pmf_dev *dev) {}
386 #endif
387 
388 static int amd_pmf_amdtee_ta_match(struct tee_ioctl_version_data *ver, const void *data)
389 {
390 	return ver->impl_id == TEE_IMPL_ID_AMDTEE;
391 }
392 
393 static int amd_pmf_ta_open_session(struct tee_context *ctx, u32 *id)
394 {
395 	struct tee_ioctl_open_session_arg sess_arg = {};
396 	int rc;
397 
398 	export_uuid(sess_arg.uuid, &amd_pmf_ta_uuid);
399 	sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
400 	sess_arg.num_params = 0;
401 
402 	rc = tee_client_open_session(ctx, &sess_arg, NULL);
403 	if (rc < 0 || sess_arg.ret != 0) {
404 		pr_err("Failed to open TEE session err:%#x, rc:%d\n", sess_arg.ret, rc);
405 		return rc;
406 	}
407 
408 	*id = sess_arg.session;
409 
410 	return rc;
411 }
412 
413 static int amd_pmf_register_input_device(struct amd_pmf_dev *dev)
414 {
415 	int err;
416 
417 	dev->pmf_idev = devm_input_allocate_device(dev->dev);
418 	if (!dev->pmf_idev)
419 		return -ENOMEM;
420 
421 	dev->pmf_idev->name = "PMF-TA output events";
422 	dev->pmf_idev->phys = "amd-pmf/input0";
423 
424 	input_set_capability(dev->pmf_idev, EV_KEY, KEY_SLEEP);
425 	input_set_capability(dev->pmf_idev, EV_KEY, KEY_SCREENLOCK);
426 	input_set_capability(dev->pmf_idev, EV_KEY, KEY_SUSPEND);
427 
428 	err = input_register_device(dev->pmf_idev);
429 	if (err) {
430 		dev_err(dev->dev, "Failed to register input device: %d\n", err);
431 		return err;
432 	}
433 
434 	return 0;
435 }
436 
437 static int amd_pmf_tee_init(struct amd_pmf_dev *dev)
438 {
439 	u32 size;
440 	int ret;
441 
442 	dev->tee_ctx = tee_client_open_context(NULL, amd_pmf_amdtee_ta_match, NULL, NULL);
443 	if (IS_ERR(dev->tee_ctx)) {
444 		dev_err(dev->dev, "Failed to open TEE context\n");
445 		return PTR_ERR(dev->tee_ctx);
446 	}
447 
448 	ret = amd_pmf_ta_open_session(dev->tee_ctx, &dev->session_id);
449 	if (ret) {
450 		dev_err(dev->dev, "Failed to open TA session (%d)\n", ret);
451 		ret = -EINVAL;
452 		goto out_ctx;
453 	}
454 
455 	size = sizeof(struct ta_pmf_shared_memory) + dev->policy_sz;
456 	dev->fw_shm_pool = tee_shm_alloc_kernel_buf(dev->tee_ctx, size);
457 	if (IS_ERR(dev->fw_shm_pool)) {
458 		dev_err(dev->dev, "Failed to alloc TEE shared memory\n");
459 		ret = PTR_ERR(dev->fw_shm_pool);
460 		goto out_sess;
461 	}
462 
463 	dev->shbuf = tee_shm_get_va(dev->fw_shm_pool, 0);
464 	if (IS_ERR(dev->shbuf)) {
465 		dev_err(dev->dev, "Failed to get TEE virtual address\n");
466 		ret = PTR_ERR(dev->shbuf);
467 		goto out_shm;
468 	}
469 	dev_dbg(dev->dev, "TEE init done\n");
470 
471 	return 0;
472 
473 out_shm:
474 	tee_shm_free(dev->fw_shm_pool);
475 out_sess:
476 	tee_client_close_session(dev->tee_ctx, dev->session_id);
477 out_ctx:
478 	tee_client_close_context(dev->tee_ctx);
479 
480 	return ret;
481 }
482 
483 static void amd_pmf_tee_deinit(struct amd_pmf_dev *dev)
484 {
485 	tee_shm_free(dev->fw_shm_pool);
486 	tee_client_close_session(dev->tee_ctx, dev->session_id);
487 	tee_client_close_context(dev->tee_ctx);
488 }
489 
490 int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev)
491 {
492 	int ret;
493 
494 	ret = apmf_check_smart_pc(dev);
495 	if (ret) {
496 		/*
497 		 * Lets not return from here if Smart PC bit is not advertised in
498 		 * the BIOS. This way, there will be some amount of power savings
499 		 * to the user with static slider (if enabled).
500 		 */
501 		dev_info(dev->dev, "PMF Smart PC not advertised in BIOS!:%d\n", ret);
502 		return -ENODEV;
503 	}
504 
505 	ret = amd_pmf_tee_init(dev);
506 	if (ret)
507 		return ret;
508 
509 	INIT_DELAYED_WORK(&dev->pb_work, amd_pmf_invoke_cmd);
510 
511 	ret = amd_pmf_set_dram_addr(dev, true);
512 	if (ret)
513 		goto error;
514 
515 	dev->policy_base = devm_ioremap(dev->dev, dev->policy_addr, dev->policy_sz);
516 	if (!dev->policy_base) {
517 		ret = -ENOMEM;
518 		goto error;
519 	}
520 
521 	dev->policy_buf = kzalloc(dev->policy_sz, GFP_KERNEL);
522 	if (!dev->policy_buf) {
523 		ret = -ENOMEM;
524 		goto error;
525 	}
526 
527 	memcpy_fromio(dev->policy_buf, dev->policy_base, dev->policy_sz);
528 
529 	amd_pmf_hex_dump_pb(dev);
530 
531 	dev->prev_data = kzalloc(sizeof(*dev->prev_data), GFP_KERNEL);
532 	if (!dev->prev_data) {
533 		ret = -ENOMEM;
534 		goto error;
535 	}
536 
537 	ret = amd_pmf_start_policy_engine(dev);
538 	if (ret)
539 		goto error;
540 
541 	if (pb_side_load)
542 		amd_pmf_open_pb(dev, dev->dbgfs_dir);
543 
544 	ret = amd_pmf_register_input_device(dev);
545 	if (ret)
546 		goto error;
547 
548 	return 0;
549 
550 error:
551 	amd_pmf_deinit_smart_pc(dev);
552 
553 	return ret;
554 }
555 
556 void amd_pmf_deinit_smart_pc(struct amd_pmf_dev *dev)
557 {
558 	if (dev->pmf_idev)
559 		input_unregister_device(dev->pmf_idev);
560 
561 	if (pb_side_load && dev->esbin)
562 		amd_pmf_remove_pb(dev);
563 
564 	cancel_delayed_work_sync(&dev->pb_work);
565 	kfree(dev->prev_data);
566 	dev->prev_data = NULL;
567 	kfree(dev->policy_buf);
568 	dev->policy_buf = NULL;
569 	kfree(dev->buf);
570 	dev->buf = NULL;
571 	amd_pmf_tee_deinit(dev);
572 }
573