xref: /linux/drivers/platform/x86/amd/pmf/tee-if.c (revision 4f77c3462308c62ffe7129cc18b9ac937f44b5a5)
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 	}
165 }
166 
167 static int amd_pmf_invoke_cmd_enact(struct amd_pmf_dev *dev)
168 {
169 	struct ta_pmf_shared_memory *ta_sm = NULL;
170 	struct ta_pmf_enact_result *out = NULL;
171 	struct ta_pmf_enact_table *in = NULL;
172 	struct tee_param param[MAX_TEE_PARAM];
173 	struct tee_ioctl_invoke_arg arg;
174 	int ret = 0;
175 
176 	if (!dev->tee_ctx)
177 		return -ENODEV;
178 
179 	memset(dev->shbuf, 0, dev->policy_sz);
180 	ta_sm = dev->shbuf;
181 	out = &ta_sm->pmf_output.policy_apply_table;
182 	in = &ta_sm->pmf_input.enact_table;
183 
184 	memset(ta_sm, 0, sizeof(*ta_sm));
185 	ta_sm->command_id = TA_PMF_COMMAND_POLICY_BUILDER_ENACT_POLICIES;
186 	ta_sm->if_version = PMF_TA_IF_VERSION_MAJOR;
187 
188 	amd_pmf_populate_ta_inputs(dev, in);
189 	amd_pmf_prepare_args(dev, TA_PMF_COMMAND_POLICY_BUILDER_ENACT_POLICIES, &arg, param);
190 
191 	ret = tee_client_invoke_func(dev->tee_ctx, &arg, param);
192 	if (ret < 0 || arg.ret != 0) {
193 		dev_err(dev->dev, "TEE enact cmd failed. err: %x, ret:%d\n", arg.ret, ret);
194 		return ret;
195 	}
196 
197 	if (ta_sm->pmf_result == TA_PMF_TYPE_SUCCESS && out->actions_count) {
198 		amd_pmf_dump_ta_inputs(dev, in);
199 		dev_dbg(dev->dev, "action count:%u result:%x\n", out->actions_count,
200 			ta_sm->pmf_result);
201 		amd_pmf_apply_policies(dev, out);
202 	}
203 
204 	return 0;
205 }
206 
207 static int amd_pmf_invoke_cmd_init(struct amd_pmf_dev *dev)
208 {
209 	struct ta_pmf_shared_memory *ta_sm = NULL;
210 	struct tee_param param[MAX_TEE_PARAM];
211 	struct ta_pmf_init_table *in = NULL;
212 	struct tee_ioctl_invoke_arg arg;
213 	int ret = 0;
214 
215 	if (!dev->tee_ctx) {
216 		dev_err(dev->dev, "Failed to get TEE context\n");
217 		return -ENODEV;
218 	}
219 
220 	dev_dbg(dev->dev, "Policy Binary size: %u bytes\n", dev->policy_sz);
221 	memset(dev->shbuf, 0, dev->policy_sz);
222 	ta_sm = dev->shbuf;
223 	in = &ta_sm->pmf_input.init_table;
224 
225 	ta_sm->command_id = TA_PMF_COMMAND_POLICY_BUILDER_INITIALIZE;
226 	ta_sm->if_version = PMF_TA_IF_VERSION_MAJOR;
227 
228 	in->metadata_macrocheck = false;
229 	in->sku_check = false;
230 	in->validate = true;
231 	in->frequency = pb_actions_ms;
232 	in->policies_table.table_size = dev->policy_sz;
233 
234 	memcpy(in->policies_table.table, dev->policy_buf, dev->policy_sz);
235 	amd_pmf_prepare_args(dev, TA_PMF_COMMAND_POLICY_BUILDER_INITIALIZE, &arg, param);
236 
237 	ret = tee_client_invoke_func(dev->tee_ctx, &arg, param);
238 	if (ret < 0 || arg.ret != 0) {
239 		dev_err(dev->dev, "Failed to invoke TEE init cmd. err: %x, ret:%d\n", arg.ret, ret);
240 		return ret;
241 	}
242 
243 	return ta_sm->pmf_result;
244 }
245 
246 static void amd_pmf_invoke_cmd(struct work_struct *work)
247 {
248 	struct amd_pmf_dev *dev = container_of(work, struct amd_pmf_dev, pb_work.work);
249 
250 	amd_pmf_invoke_cmd_enact(dev);
251 	schedule_delayed_work(&dev->pb_work, msecs_to_jiffies(pb_actions_ms));
252 }
253 
254 static int amd_pmf_start_policy_engine(struct amd_pmf_dev *dev)
255 {
256 	struct cookie_header *header;
257 	int res;
258 
259 	if (dev->policy_sz < POLICY_COOKIE_OFFSET + sizeof(*header))
260 		return -EINVAL;
261 
262 	header = (struct cookie_header *)(dev->policy_buf + POLICY_COOKIE_OFFSET);
263 
264 	if (header->sign != POLICY_SIGN_COOKIE || !header->length) {
265 		dev_dbg(dev->dev, "cookie doesn't match\n");
266 		return -EINVAL;
267 	}
268 
269 	if (dev->policy_sz < header->length + 512)
270 		return -EINVAL;
271 
272 	/* Update the actual length */
273 	dev->policy_sz = header->length + 512;
274 	res = amd_pmf_invoke_cmd_init(dev);
275 	if (res == TA_PMF_TYPE_SUCCESS) {
276 		/* Now its safe to announce that smart pc is enabled */
277 		dev->smart_pc_enabled = true;
278 		/*
279 		 * Start collecting the data from TA FW after a small delay
280 		 * or else, we might end up getting stale values.
281 		 */
282 		schedule_delayed_work(&dev->pb_work, msecs_to_jiffies(pb_actions_ms * 3));
283 	} else {
284 		dev_err(dev->dev, "ta invoke cmd init failed err: %x\n", res);
285 		dev->smart_pc_enabled = false;
286 		return -EIO;
287 	}
288 
289 	return 0;
290 }
291 
292 #ifdef CONFIG_AMD_PMF_DEBUG
293 static void amd_pmf_hex_dump_pb(struct amd_pmf_dev *dev)
294 {
295 	print_hex_dump_debug("(pb):  ", DUMP_PREFIX_OFFSET, 16, 1, dev->policy_buf,
296 			     dev->policy_sz, false);
297 }
298 
299 static ssize_t amd_pmf_get_pb_data(struct file *filp, const char __user *buf,
300 				   size_t length, loff_t *pos)
301 {
302 	struct amd_pmf_dev *dev = filp->private_data;
303 	unsigned char *new_policy_buf;
304 	int ret;
305 
306 	/* Policy binary size cannot exceed POLICY_BUF_MAX_SZ */
307 	if (length > POLICY_BUF_MAX_SZ || length == 0)
308 		return -EINVAL;
309 
310 	/* re-alloc to the new buffer length of the policy binary */
311 	new_policy_buf = memdup_user(buf, length);
312 	if (IS_ERR(new_policy_buf))
313 		return PTR_ERR(new_policy_buf);
314 
315 	kfree(dev->policy_buf);
316 	dev->policy_buf = new_policy_buf;
317 	dev->policy_sz = length;
318 
319 	amd_pmf_hex_dump_pb(dev);
320 	ret = amd_pmf_start_policy_engine(dev);
321 	if (ret < 0)
322 		return ret;
323 
324 	return length;
325 }
326 
327 static const struct file_operations pb_fops = {
328 	.write = amd_pmf_get_pb_data,
329 	.open = simple_open,
330 };
331 
332 static void amd_pmf_open_pb(struct amd_pmf_dev *dev, struct dentry *debugfs_root)
333 {
334 	dev->esbin = debugfs_create_dir("pb", debugfs_root);
335 	debugfs_create_file("update_policy", 0644, dev->esbin, dev, &pb_fops);
336 }
337 
338 static void amd_pmf_remove_pb(struct amd_pmf_dev *dev)
339 {
340 	debugfs_remove_recursive(dev->esbin);
341 }
342 #else
343 static void amd_pmf_open_pb(struct amd_pmf_dev *dev, struct dentry *debugfs_root) {}
344 static void amd_pmf_remove_pb(struct amd_pmf_dev *dev) {}
345 static void amd_pmf_hex_dump_pb(struct amd_pmf_dev *dev) {}
346 #endif
347 
348 static int amd_pmf_amdtee_ta_match(struct tee_ioctl_version_data *ver, const void *data)
349 {
350 	return ver->impl_id == TEE_IMPL_ID_AMDTEE;
351 }
352 
353 static int amd_pmf_ta_open_session(struct tee_context *ctx, u32 *id)
354 {
355 	struct tee_ioctl_open_session_arg sess_arg = {};
356 	int rc;
357 
358 	export_uuid(sess_arg.uuid, &amd_pmf_ta_uuid);
359 	sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
360 	sess_arg.num_params = 0;
361 
362 	rc = tee_client_open_session(ctx, &sess_arg, NULL);
363 	if (rc < 0 || sess_arg.ret != 0) {
364 		pr_err("Failed to open TEE session err:%#x, rc:%d\n", sess_arg.ret, rc);
365 		return rc;
366 	}
367 
368 	*id = sess_arg.session;
369 
370 	return rc;
371 }
372 
373 static int amd_pmf_register_input_device(struct amd_pmf_dev *dev)
374 {
375 	int err;
376 
377 	dev->pmf_idev = devm_input_allocate_device(dev->dev);
378 	if (!dev->pmf_idev)
379 		return -ENOMEM;
380 
381 	dev->pmf_idev->name = "PMF-TA output events";
382 	dev->pmf_idev->phys = "amd-pmf/input0";
383 
384 	input_set_capability(dev->pmf_idev, EV_KEY, KEY_SLEEP);
385 	input_set_capability(dev->pmf_idev, EV_KEY, KEY_SCREENLOCK);
386 	input_set_capability(dev->pmf_idev, EV_KEY, KEY_SUSPEND);
387 
388 	err = input_register_device(dev->pmf_idev);
389 	if (err) {
390 		dev_err(dev->dev, "Failed to register input device: %d\n", err);
391 		return err;
392 	}
393 
394 	return 0;
395 }
396 
397 static int amd_pmf_tee_init(struct amd_pmf_dev *dev)
398 {
399 	u32 size;
400 	int ret;
401 
402 	dev->tee_ctx = tee_client_open_context(NULL, amd_pmf_amdtee_ta_match, NULL, NULL);
403 	if (IS_ERR(dev->tee_ctx)) {
404 		dev_err(dev->dev, "Failed to open TEE context\n");
405 		return PTR_ERR(dev->tee_ctx);
406 	}
407 
408 	ret = amd_pmf_ta_open_session(dev->tee_ctx, &dev->session_id);
409 	if (ret) {
410 		dev_err(dev->dev, "Failed to open TA session (%d)\n", ret);
411 		ret = -EINVAL;
412 		goto out_ctx;
413 	}
414 
415 	size = sizeof(struct ta_pmf_shared_memory) + dev->policy_sz;
416 	dev->fw_shm_pool = tee_shm_alloc_kernel_buf(dev->tee_ctx, size);
417 	if (IS_ERR(dev->fw_shm_pool)) {
418 		dev_err(dev->dev, "Failed to alloc TEE shared memory\n");
419 		ret = PTR_ERR(dev->fw_shm_pool);
420 		goto out_sess;
421 	}
422 
423 	dev->shbuf = tee_shm_get_va(dev->fw_shm_pool, 0);
424 	if (IS_ERR(dev->shbuf)) {
425 		dev_err(dev->dev, "Failed to get TEE virtual address\n");
426 		ret = PTR_ERR(dev->shbuf);
427 		goto out_shm;
428 	}
429 	dev_dbg(dev->dev, "TEE init done\n");
430 
431 	return 0;
432 
433 out_shm:
434 	tee_shm_free(dev->fw_shm_pool);
435 out_sess:
436 	tee_client_close_session(dev->tee_ctx, dev->session_id);
437 out_ctx:
438 	tee_client_close_context(dev->tee_ctx);
439 
440 	return ret;
441 }
442 
443 static void amd_pmf_tee_deinit(struct amd_pmf_dev *dev)
444 {
445 	tee_shm_free(dev->fw_shm_pool);
446 	tee_client_close_session(dev->tee_ctx, dev->session_id);
447 	tee_client_close_context(dev->tee_ctx);
448 }
449 
450 int amd_pmf_init_smart_pc(struct amd_pmf_dev *dev)
451 {
452 	int ret;
453 
454 	ret = apmf_check_smart_pc(dev);
455 	if (ret) {
456 		/*
457 		 * Lets not return from here if Smart PC bit is not advertised in
458 		 * the BIOS. This way, there will be some amount of power savings
459 		 * to the user with static slider (if enabled).
460 		 */
461 		dev_info(dev->dev, "PMF Smart PC not advertised in BIOS!:%d\n", ret);
462 		return -ENODEV;
463 	}
464 
465 	ret = amd_pmf_tee_init(dev);
466 	if (ret)
467 		return ret;
468 
469 	INIT_DELAYED_WORK(&dev->pb_work, amd_pmf_invoke_cmd);
470 
471 	ret = amd_pmf_set_dram_addr(dev, true);
472 	if (ret)
473 		goto error;
474 
475 	dev->policy_base = devm_ioremap(dev->dev, dev->policy_addr, dev->policy_sz);
476 	if (!dev->policy_base) {
477 		ret = -ENOMEM;
478 		goto error;
479 	}
480 
481 	dev->policy_buf = kzalloc(dev->policy_sz, GFP_KERNEL);
482 	if (!dev->policy_buf) {
483 		ret = -ENOMEM;
484 		goto error;
485 	}
486 
487 	memcpy_fromio(dev->policy_buf, dev->policy_base, dev->policy_sz);
488 
489 	amd_pmf_hex_dump_pb(dev);
490 
491 	dev->prev_data = kzalloc(sizeof(*dev->prev_data), GFP_KERNEL);
492 	if (!dev->prev_data) {
493 		ret = -ENOMEM;
494 		goto error;
495 	}
496 
497 	ret = amd_pmf_start_policy_engine(dev);
498 	if (ret)
499 		goto error;
500 
501 	if (pb_side_load)
502 		amd_pmf_open_pb(dev, dev->dbgfs_dir);
503 
504 	ret = amd_pmf_register_input_device(dev);
505 	if (ret)
506 		goto error;
507 
508 	return 0;
509 
510 error:
511 	amd_pmf_deinit_smart_pc(dev);
512 
513 	return ret;
514 }
515 
516 void amd_pmf_deinit_smart_pc(struct amd_pmf_dev *dev)
517 {
518 	if (dev->pmf_idev)
519 		input_unregister_device(dev->pmf_idev);
520 
521 	if (pb_side_load && dev->esbin)
522 		amd_pmf_remove_pb(dev);
523 
524 	cancel_delayed_work_sync(&dev->pb_work);
525 	kfree(dev->prev_data);
526 	dev->prev_data = NULL;
527 	kfree(dev->policy_buf);
528 	dev->policy_buf = NULL;
529 	kfree(dev->buf);
530 	dev->buf = NULL;
531 	amd_pmf_tee_deinit(dev);
532 }
533