xref: /linux/drivers/gpu/drm/amd/display/modules/hdcp/hdcp.c (revision 8137a49e1567726eb10fcf55ad141ac19804ca6b)
1 /*
2  * Copyright 2019 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: AMD
23  *
24  */
25 
26 #include "hdcp.h"
27 
28 static void push_error_status(struct mod_hdcp *hdcp,
29 		enum mod_hdcp_status status)
30 {
31 	struct mod_hdcp_trace *trace = &hdcp->connection.trace;
32 
33 	if (trace->error_count < MAX_NUM_OF_ERROR_TRACE) {
34 		trace->errors[trace->error_count].status = status;
35 		trace->errors[trace->error_count].state_id = hdcp->state.id;
36 		trace->error_count++;
37 		HDCP_ERROR_TRACE(hdcp, status);
38 	}
39 
40 	if (is_hdcp1(hdcp)) {
41 		hdcp->connection.hdcp1_retry_count++;
42 	} else if (is_hdcp2(hdcp)) {
43 		hdcp->connection.hdcp2_retry_count++;
44 	}
45 }
46 
47 static uint8_t is_cp_desired_hdcp1(struct mod_hdcp *hdcp)
48 {
49 	int i, is_auth_needed = 0;
50 
51 	/* if all displays on the link don't need authentication,
52 	 * hdcp is not desired
53 	 */
54 	for (i = 0; i < MAX_NUM_OF_DISPLAYS; i++) {
55 		if (hdcp->displays[i].state != MOD_HDCP_DISPLAY_INACTIVE &&
56 				hdcp->displays[i].adjust.disable != MOD_HDCP_DISPLAY_DISABLE_AUTHENTICATION) {
57 			is_auth_needed = 1;
58 			break;
59 		}
60 	}
61 
62 	return (hdcp->connection.hdcp1_retry_count < MAX_NUM_OF_ATTEMPTS) &&
63 			is_auth_needed &&
64 			!hdcp->connection.link.adjust.hdcp1.disable &&
65 			!hdcp->connection.is_hdcp1_revoked;
66 }
67 
68 static uint8_t is_cp_desired_hdcp2(struct mod_hdcp *hdcp)
69 {
70 	int i, is_auth_needed = 0;
71 
72 	/* if all displays on the link don't need authentication,
73 	 * hdcp is not desired
74 	 */
75 	for (i = 0; i < MAX_NUM_OF_DISPLAYS; i++) {
76 		if (hdcp->displays[i].state != MOD_HDCP_DISPLAY_INACTIVE &&
77 				hdcp->displays[i].adjust.disable != MOD_HDCP_DISPLAY_DISABLE_AUTHENTICATION) {
78 			is_auth_needed = 1;
79 			break;
80 		}
81 	}
82 
83 	return (hdcp->connection.hdcp2_retry_count < MAX_NUM_OF_ATTEMPTS) &&
84 			is_auth_needed &&
85 			!hdcp->connection.link.adjust.hdcp2.disable &&
86 			!hdcp->connection.is_hdcp2_revoked;
87 }
88 
89 static enum mod_hdcp_status execution(struct mod_hdcp *hdcp,
90 		struct mod_hdcp_event_context *event_ctx,
91 		union mod_hdcp_transition_input *input)
92 {
93 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
94 
95 	if (is_in_initialized_state(hdcp)) {
96 		if (event_ctx->event != MOD_HDCP_EVENT_CALLBACK) {
97 			event_ctx->unexpected_event = 1;
98 			goto out;
99 		}
100 		/* initialize transition input */
101 		memset(input, 0, sizeof(union mod_hdcp_transition_input));
102 	} else if (is_in_cp_not_desired_state(hdcp)) {
103 		if (event_ctx->event != MOD_HDCP_EVENT_CALLBACK) {
104 			event_ctx->unexpected_event = 1;
105 			goto out;
106 		}
107 	} else if (is_in_hdcp1_states(hdcp)) {
108 		status = mod_hdcp_hdcp1_execution(hdcp, event_ctx, &input->hdcp1);
109 	} else if (is_in_hdcp1_dp_states(hdcp)) {
110 		status = mod_hdcp_hdcp1_dp_execution(hdcp,
111 				event_ctx, &input->hdcp1);
112 	} else if (is_in_hdcp2_states(hdcp)) {
113 		status = mod_hdcp_hdcp2_execution(hdcp, event_ctx, &input->hdcp2);
114 	} else if (is_in_hdcp2_dp_states(hdcp)) {
115 		status = mod_hdcp_hdcp2_dp_execution(hdcp,
116 				event_ctx, &input->hdcp2);
117 	} else {
118 		event_ctx->unexpected_event = 1;
119 		goto out;
120 	}
121 out:
122 	return status;
123 }
124 
125 static enum mod_hdcp_status transition(struct mod_hdcp *hdcp,
126 		struct mod_hdcp_event_context *event_ctx,
127 		union mod_hdcp_transition_input *input,
128 		struct mod_hdcp_output *output)
129 {
130 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
131 
132 	if (event_ctx->unexpected_event)
133 		goto out;
134 
135 	if (is_in_initialized_state(hdcp)) {
136 		if (is_dp_hdcp(hdcp))
137 			if (is_cp_desired_hdcp2(hdcp)) {
138 				callback_in_ms(0, output);
139 				set_state_id(hdcp, output, D2_A0_DETERMINE_RX_HDCP_CAPABLE);
140 			} else if (is_cp_desired_hdcp1(hdcp)) {
141 				callback_in_ms(0, output);
142 				set_state_id(hdcp, output, D1_A0_DETERMINE_RX_HDCP_CAPABLE);
143 			} else {
144 				callback_in_ms(0, output);
145 				set_state_id(hdcp, output, HDCP_CP_NOT_DESIRED);
146 			}
147 		else if (is_hdmi_dvi_sl_hdcp(hdcp))
148 			if (is_cp_desired_hdcp2(hdcp)) {
149 				callback_in_ms(0, output);
150 				set_state_id(hdcp, output, H2_A0_KNOWN_HDCP2_CAPABLE_RX);
151 			} else if (is_cp_desired_hdcp1(hdcp)) {
152 				callback_in_ms(0, output);
153 				set_state_id(hdcp, output, H1_A0_WAIT_FOR_ACTIVE_RX);
154 			} else {
155 				callback_in_ms(0, output);
156 				set_state_id(hdcp, output, HDCP_CP_NOT_DESIRED);
157 			}
158 		else {
159 			callback_in_ms(0, output);
160 			set_state_id(hdcp, output, HDCP_CP_NOT_DESIRED);
161 		}
162 	} else if (is_in_cp_not_desired_state(hdcp)) {
163 		increment_stay_counter(hdcp);
164 	} else if (is_in_hdcp1_states(hdcp)) {
165 		status = mod_hdcp_hdcp1_transition(hdcp,
166 				event_ctx, &input->hdcp1, output);
167 	} else if (is_in_hdcp1_dp_states(hdcp)) {
168 		status = mod_hdcp_hdcp1_dp_transition(hdcp,
169 				event_ctx, &input->hdcp1, output);
170 	} else if (is_in_hdcp2_states(hdcp)) {
171 		status = mod_hdcp_hdcp2_transition(hdcp,
172 				event_ctx, &input->hdcp2, output);
173 	} else if (is_in_hdcp2_dp_states(hdcp)) {
174 		status = mod_hdcp_hdcp2_dp_transition(hdcp,
175 				event_ctx, &input->hdcp2, output);
176 	} else {
177 		status = MOD_HDCP_STATUS_INVALID_STATE;
178 	}
179 out:
180 	return status;
181 }
182 
183 static enum mod_hdcp_status reset_authentication(struct mod_hdcp *hdcp,
184 		struct mod_hdcp_output *output)
185 {
186 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
187 
188 	if (is_hdcp1(hdcp)) {
189 		if (hdcp->auth.trans_input.hdcp1.create_session != UNKNOWN) {
190 			/* TODO - update psp to unify create session failure
191 			 * recovery between hdcp1 and 2.
192 			 */
193 			mod_hdcp_hdcp1_destroy_session(hdcp);
194 
195 		}
196 
197 		HDCP_TOP_RESET_AUTH_TRACE(hdcp);
198 		memset(&hdcp->auth, 0, sizeof(struct mod_hdcp_authentication));
199 		memset(&hdcp->state, 0, sizeof(struct mod_hdcp_state));
200 		set_state_id(hdcp, output, HDCP_INITIALIZED);
201 	} else if (is_hdcp2(hdcp)) {
202 		if (hdcp->auth.trans_input.hdcp2.create_session == PASS) {
203 			status = mod_hdcp_hdcp2_destroy_session(hdcp);
204 			if (status != MOD_HDCP_STATUS_SUCCESS) {
205 				output->callback_needed = 0;
206 				output->watchdog_timer_needed = 0;
207 				goto out;
208 			}
209 		}
210 
211 		HDCP_TOP_RESET_AUTH_TRACE(hdcp);
212 		memset(&hdcp->auth, 0, sizeof(struct mod_hdcp_authentication));
213 		memset(&hdcp->state, 0, sizeof(struct mod_hdcp_state));
214 		set_state_id(hdcp, output, HDCP_INITIALIZED);
215 	} else if (is_in_cp_not_desired_state(hdcp)) {
216 		HDCP_TOP_RESET_AUTH_TRACE(hdcp);
217 		memset(&hdcp->auth, 0, sizeof(struct mod_hdcp_authentication));
218 		memset(&hdcp->state, 0, sizeof(struct mod_hdcp_state));
219 		set_state_id(hdcp, output, HDCP_INITIALIZED);
220 	}
221 
222 out:
223 	/* stop callback and watchdog requests from previous authentication*/
224 	output->watchdog_timer_stop = 1;
225 	output->callback_stop = 1;
226 	return status;
227 }
228 
229 static enum mod_hdcp_status reset_connection(struct mod_hdcp *hdcp,
230 		struct mod_hdcp_output *output)
231 {
232 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
233 
234 	memset(output, 0, sizeof(struct mod_hdcp_output));
235 
236 	status = reset_authentication(hdcp, output);
237 	if (status != MOD_HDCP_STATUS_SUCCESS)
238 		goto out;
239 
240 	if (current_state(hdcp) != HDCP_UNINITIALIZED) {
241 		HDCP_TOP_RESET_CONN_TRACE(hdcp);
242 		set_state_id(hdcp, output, HDCP_UNINITIALIZED);
243 	}
244 	memset(&hdcp->connection, 0, sizeof(hdcp->connection));
245 out:
246 	return status;
247 }
248 
249 /*
250  * Implementation of functions in mod_hdcp.h
251  */
252 size_t mod_hdcp_get_memory_size(void)
253 {
254 	return sizeof(struct mod_hdcp);
255 }
256 
257 enum mod_hdcp_status mod_hdcp_setup(struct mod_hdcp *hdcp,
258 		struct mod_hdcp_config *config)
259 {
260 	struct mod_hdcp_output output;
261 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
262 
263 	memset(&output, 0, sizeof(output));
264 	hdcp->config = *config;
265 	HDCP_TOP_INTERFACE_TRACE(hdcp);
266 	status = reset_connection(hdcp, &output);
267 	if (status != MOD_HDCP_STATUS_SUCCESS)
268 		push_error_status(hdcp, status);
269 	return status;
270 }
271 
272 enum mod_hdcp_status mod_hdcp_teardown(struct mod_hdcp *hdcp)
273 {
274 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
275 	struct mod_hdcp_output output;
276 
277 	HDCP_TOP_INTERFACE_TRACE(hdcp);
278 	memset(&output, 0,  sizeof(output));
279 	status = reset_connection(hdcp, &output);
280 	if (status == MOD_HDCP_STATUS_SUCCESS)
281 		memset(hdcp, 0, sizeof(struct mod_hdcp));
282 	else
283 		push_error_status(hdcp, status);
284 	return status;
285 }
286 
287 enum mod_hdcp_status mod_hdcp_add_display(struct mod_hdcp *hdcp,
288 		struct mod_hdcp_link *link, struct mod_hdcp_display *display,
289 		struct mod_hdcp_output *output)
290 {
291 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
292 	struct mod_hdcp_display *display_container = NULL;
293 
294 	HDCP_TOP_INTERFACE_TRACE_WITH_INDEX(hdcp, display->index);
295 	memset(output, 0, sizeof(struct mod_hdcp_output));
296 
297 	/* skip inactive display */
298 	if (display->state != MOD_HDCP_DISPLAY_ACTIVE) {
299 		status = MOD_HDCP_STATUS_SUCCESS;
300 		goto out;
301 	}
302 
303 	/* check existing display container */
304 	if (get_active_display_at_index(hdcp, display->index)) {
305 		status = MOD_HDCP_STATUS_SUCCESS;
306 		goto out;
307 	}
308 
309 	/* find an empty display container */
310 	display_container = get_empty_display_container(hdcp);
311 	if (!display_container) {
312 		status = MOD_HDCP_STATUS_DISPLAY_OUT_OF_BOUND;
313 		goto out;
314 	}
315 
316 	/* save current encryption states to restore after next authentication */
317 	mod_hdcp_save_current_encryption_states(hdcp);
318 
319 	/* reset existing authentication status */
320 	status = reset_authentication(hdcp, output);
321 	if (status != MOD_HDCP_STATUS_SUCCESS)
322 		goto out;
323 
324 	/* reset retry counters */
325 	reset_retry_counts(hdcp);
326 
327 	/* reset error trace */
328 	memset(&hdcp->connection.trace, 0, sizeof(hdcp->connection.trace));
329 
330 	/* add display to connection */
331 	hdcp->connection.link = *link;
332 	*display_container = *display;
333 	status = mod_hdcp_add_display_to_topology(hdcp, display_container);
334 
335 	if (status != MOD_HDCP_STATUS_SUCCESS)
336 		goto out;
337 
338 	/* request authentication */
339 	if (current_state(hdcp) != HDCP_INITIALIZED)
340 		set_state_id(hdcp, output, HDCP_INITIALIZED);
341 	callback_in_ms(hdcp->connection.link.adjust.auth_delay * 1000, output);
342 out:
343 	if (status != MOD_HDCP_STATUS_SUCCESS)
344 		push_error_status(hdcp, status);
345 
346 	return status;
347 }
348 
349 enum mod_hdcp_status mod_hdcp_remove_display(struct mod_hdcp *hdcp,
350 		uint8_t index, struct mod_hdcp_output *output)
351 {
352 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
353 	struct mod_hdcp_display *display = NULL;
354 
355 	HDCP_TOP_INTERFACE_TRACE_WITH_INDEX(hdcp, index);
356 	memset(output, 0, sizeof(struct mod_hdcp_output));
357 
358 	/* find display in connection */
359 	display = get_active_display_at_index(hdcp, index);
360 	if (!display) {
361 		status = MOD_HDCP_STATUS_SUCCESS;
362 		goto out;
363 	}
364 
365 	/* save current encryption states to restore after next authentication */
366 	mod_hdcp_save_current_encryption_states(hdcp);
367 
368 	/* stop current authentication */
369 	status = reset_authentication(hdcp, output);
370 	if (status != MOD_HDCP_STATUS_SUCCESS)
371 		goto out;
372 
373 	/* clear retry counters */
374 	reset_retry_counts(hdcp);
375 
376 	/* reset error trace */
377 	memset(&hdcp->connection.trace, 0, sizeof(hdcp->connection.trace));
378 
379 	/* remove display */
380 	status = mod_hdcp_remove_display_from_topology(hdcp, index);
381 	if (status != MOD_HDCP_STATUS_SUCCESS)
382 		goto out;
383 	memset(display, 0, sizeof(struct mod_hdcp_display));
384 
385 	/* request authentication when connection is not reset */
386 	if (current_state(hdcp) != HDCP_UNINITIALIZED)
387 		callback_in_ms(hdcp->connection.link.adjust.auth_delay * 1000,
388 				output);
389 out:
390 	if (status != MOD_HDCP_STATUS_SUCCESS)
391 		push_error_status(hdcp, status);
392 	return status;
393 }
394 
395 enum mod_hdcp_status mod_hdcp_query_display(struct mod_hdcp *hdcp,
396 		uint8_t index, struct mod_hdcp_display_query *query)
397 {
398 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
399 	struct mod_hdcp_display *display = NULL;
400 
401 	/* find display in connection */
402 	display = get_active_display_at_index(hdcp, index);
403 	if (!display) {
404 		status = MOD_HDCP_STATUS_DISPLAY_NOT_FOUND;
405 		goto out;
406 	}
407 
408 	/* populate query */
409 	query->link = &hdcp->connection.link;
410 	query->display = display;
411 	query->trace = &hdcp->connection.trace;
412 	query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF;
413 
414 	if (is_display_encryption_enabled(display)) {
415 		if (is_hdcp1(hdcp)) {
416 			query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP1_ON;
417 		} else if (is_hdcp2(hdcp)) {
418 			if (query->link->adjust.hdcp2.force_type == MOD_HDCP_FORCE_TYPE_0)
419 				query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE0_ON;
420 			else if (query->link->adjust.hdcp2.force_type == MOD_HDCP_FORCE_TYPE_1)
421 				query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE1_ON;
422 			else
423 				query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_ON;
424 		}
425 	} else {
426 		query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF;
427 	}
428 
429 out:
430 	return status;
431 }
432 
433 enum mod_hdcp_status mod_hdcp_reset_connection(struct mod_hdcp *hdcp,
434 		struct mod_hdcp_output *output)
435 {
436 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
437 
438 	HDCP_TOP_INTERFACE_TRACE(hdcp);
439 	status = reset_connection(hdcp, output);
440 	if (status != MOD_HDCP_STATUS_SUCCESS)
441 		push_error_status(hdcp, status);
442 
443 	return status;
444 }
445 
446 enum mod_hdcp_status mod_hdcp_process_event(struct mod_hdcp *hdcp,
447 		enum mod_hdcp_event event, struct mod_hdcp_output *output)
448 {
449 	enum mod_hdcp_status exec_status, trans_status, reset_status, status;
450 	struct mod_hdcp_event_context event_ctx;
451 
452 	HDCP_EVENT_TRACE(hdcp, event);
453 	memset(output, 0, sizeof(struct mod_hdcp_output));
454 	memset(&event_ctx, 0, sizeof(struct mod_hdcp_event_context));
455 	event_ctx.event = event;
456 
457 	/* execute and transition */
458 	exec_status = execution(hdcp, &event_ctx, &hdcp->auth.trans_input);
459 	trans_status = transition(
460 			hdcp, &event_ctx, &hdcp->auth.trans_input, output);
461 	if (trans_status == MOD_HDCP_STATUS_SUCCESS) {
462 		status = MOD_HDCP_STATUS_SUCCESS;
463 	} else if (exec_status == MOD_HDCP_STATUS_SUCCESS) {
464 		status = MOD_HDCP_STATUS_INTERNAL_POLICY_FAILURE;
465 		push_error_status(hdcp, status);
466 	} else {
467 		status = exec_status;
468 		push_error_status(hdcp, status);
469 	}
470 
471 	/* reset authentication if needed */
472 	if (trans_status == MOD_HDCP_STATUS_RESET_NEEDED) {
473 		HDCP_FULL_DDC_TRACE(hdcp);
474 		reset_status = reset_authentication(hdcp, output);
475 		if (reset_status != MOD_HDCP_STATUS_SUCCESS)
476 			push_error_status(hdcp, reset_status);
477 	}
478 
479 	/* Clear CP_IRQ status if needed */
480 	if (event_ctx.event == MOD_HDCP_EVENT_CPIRQ) {
481 		status = mod_hdcp_clear_cp_irq_status(hdcp);
482 		if (status != MOD_HDCP_STATUS_SUCCESS)
483 			push_error_status(hdcp, status);
484 	}
485 
486 	return status;
487 }
488 
489 enum mod_hdcp_operation_mode mod_hdcp_signal_type_to_operation_mode(
490 		enum signal_type signal)
491 {
492 	enum mod_hdcp_operation_mode mode = MOD_HDCP_MODE_OFF;
493 
494 	switch (signal) {
495 	case SIGNAL_TYPE_DVI_SINGLE_LINK:
496 	case SIGNAL_TYPE_HDMI_TYPE_A:
497 		mode = MOD_HDCP_MODE_DEFAULT;
498 		break;
499 	case SIGNAL_TYPE_EDP:
500 	case SIGNAL_TYPE_DISPLAY_PORT:
501 	case SIGNAL_TYPE_DISPLAY_PORT_MST:
502 		mode = MOD_HDCP_MODE_DP;
503 		break;
504 	default:
505 		break;
506 	}
507 
508 	return mode;
509 }
510