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) {
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) {
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(hdcp, 0, sizeof(struct mod_hdcp));
264 	memset(&output, 0, sizeof(output));
265 	hdcp->config = *config;
266 	HDCP_TOP_INTERFACE_TRACE(hdcp);
267 	status = reset_connection(hdcp, &output);
268 	if (status != MOD_HDCP_STATUS_SUCCESS)
269 		push_error_status(hdcp, status);
270 	return status;
271 }
272 
273 enum mod_hdcp_status mod_hdcp_teardown(struct mod_hdcp *hdcp)
274 {
275 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
276 	struct mod_hdcp_output output;
277 
278 	HDCP_TOP_INTERFACE_TRACE(hdcp);
279 	memset(&output, 0,  sizeof(output));
280 	status = reset_connection(hdcp, &output);
281 	if (status == MOD_HDCP_STATUS_SUCCESS)
282 		memset(hdcp, 0, sizeof(struct mod_hdcp));
283 	else
284 		push_error_status(hdcp, status);
285 	return status;
286 }
287 
288 enum mod_hdcp_status mod_hdcp_add_display(struct mod_hdcp *hdcp,
289 		struct mod_hdcp_link *link, struct mod_hdcp_display *display,
290 		struct mod_hdcp_output *output)
291 {
292 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
293 	struct mod_hdcp_display *display_container = NULL;
294 
295 	HDCP_TOP_INTERFACE_TRACE_WITH_INDEX(hdcp, display->index);
296 	memset(output, 0, sizeof(struct mod_hdcp_output));
297 
298 	/* skip inactive display */
299 	if (display->state != MOD_HDCP_DISPLAY_ACTIVE) {
300 		status = MOD_HDCP_STATUS_SUCCESS;
301 		goto out;
302 	}
303 
304 	/* check existing display container */
305 	if (get_active_display_at_index(hdcp, display->index)) {
306 		status = MOD_HDCP_STATUS_SUCCESS;
307 		goto out;
308 	}
309 
310 	/* find an empty display container */
311 	display_container = get_empty_display_container(hdcp);
312 	if (!display_container) {
313 		status = MOD_HDCP_STATUS_DISPLAY_OUT_OF_BOUND;
314 		goto out;
315 	}
316 
317 	/* reset existing authentication status */
318 	status = reset_authentication(hdcp, output);
319 	if (status != MOD_HDCP_STATUS_SUCCESS)
320 		goto out;
321 
322 	/* reset retry counters */
323 	reset_retry_counts(hdcp);
324 
325 	/* reset error trace */
326 	memset(&hdcp->connection.trace, 0, sizeof(hdcp->connection.trace));
327 
328 	/* add display to connection */
329 	hdcp->connection.link = *link;
330 	*display_container = *display;
331 	status = mod_hdcp_add_display_to_topology(hdcp, display_container);
332 
333 	if (status != MOD_HDCP_STATUS_SUCCESS)
334 		goto out;
335 
336 	/* request authentication */
337 	if (current_state(hdcp) != HDCP_INITIALIZED)
338 		set_state_id(hdcp, output, HDCP_INITIALIZED);
339 	callback_in_ms(hdcp->connection.link.adjust.auth_delay * 1000, output);
340 out:
341 	if (status != MOD_HDCP_STATUS_SUCCESS)
342 		push_error_status(hdcp, status);
343 
344 	return status;
345 }
346 
347 enum mod_hdcp_status mod_hdcp_remove_display(struct mod_hdcp *hdcp,
348 		uint8_t index, struct mod_hdcp_output *output)
349 {
350 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
351 	struct mod_hdcp_display *display = NULL;
352 
353 	HDCP_TOP_INTERFACE_TRACE_WITH_INDEX(hdcp, index);
354 	memset(output, 0, sizeof(struct mod_hdcp_output));
355 
356 	/* find display in connection */
357 	display = get_active_display_at_index(hdcp, index);
358 	if (!display) {
359 		status = MOD_HDCP_STATUS_SUCCESS;
360 		goto out;
361 	}
362 
363 	/* stop current authentication */
364 	status = reset_authentication(hdcp, output);
365 	if (status != MOD_HDCP_STATUS_SUCCESS)
366 		goto out;
367 
368 	/* clear retry counters */
369 	reset_retry_counts(hdcp);
370 
371 	/* reset error trace */
372 	memset(&hdcp->connection.trace, 0, sizeof(hdcp->connection.trace));
373 
374 	/* remove display */
375 	status = mod_hdcp_remove_display_from_topology(hdcp, index);
376 	if (status != MOD_HDCP_STATUS_SUCCESS)
377 		goto out;
378 	memset(display, 0, sizeof(struct mod_hdcp_display));
379 
380 	/* request authentication when connection is not reset */
381 	if (current_state(hdcp) != HDCP_UNINITIALIZED)
382 		callback_in_ms(hdcp->connection.link.adjust.auth_delay * 1000,
383 				output);
384 out:
385 	if (status != MOD_HDCP_STATUS_SUCCESS)
386 		push_error_status(hdcp, status);
387 	return status;
388 }
389 
390 enum mod_hdcp_status mod_hdcp_query_display(struct mod_hdcp *hdcp,
391 		uint8_t index, struct mod_hdcp_display_query *query)
392 {
393 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
394 	struct mod_hdcp_display *display = NULL;
395 
396 	/* find display in connection */
397 	display = get_active_display_at_index(hdcp, index);
398 	if (!display) {
399 		status = MOD_HDCP_STATUS_DISPLAY_NOT_FOUND;
400 		goto out;
401 	}
402 
403 	/* populate query */
404 	query->link = &hdcp->connection.link;
405 	query->display = display;
406 	query->trace = &hdcp->connection.trace;
407 	query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF;
408 
409 	if (is_display_encryption_enabled(display)) {
410 		if (is_hdcp1(hdcp)) {
411 			query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP1_ON;
412 		} else if (is_hdcp2(hdcp)) {
413 			if (query->link->adjust.hdcp2.force_type == MOD_HDCP_FORCE_TYPE_0)
414 				query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE0_ON;
415 			else if (query->link->adjust.hdcp2.force_type == MOD_HDCP_FORCE_TYPE_1)
416 				query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE1_ON;
417 			else
418 				query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP2_ON;
419 		}
420 	} else {
421 		query->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF;
422 	}
423 
424 out:
425 	return status;
426 }
427 
428 enum mod_hdcp_status mod_hdcp_reset_connection(struct mod_hdcp *hdcp,
429 		struct mod_hdcp_output *output)
430 {
431 	enum mod_hdcp_status status = MOD_HDCP_STATUS_SUCCESS;
432 
433 	HDCP_TOP_INTERFACE_TRACE(hdcp);
434 	status = reset_connection(hdcp, output);
435 	if (status != MOD_HDCP_STATUS_SUCCESS)
436 		push_error_status(hdcp, status);
437 
438 	return status;
439 }
440 
441 enum mod_hdcp_status mod_hdcp_process_event(struct mod_hdcp *hdcp,
442 		enum mod_hdcp_event event, struct mod_hdcp_output *output)
443 {
444 	enum mod_hdcp_status exec_status, trans_status, reset_status, status;
445 	struct mod_hdcp_event_context event_ctx;
446 
447 	HDCP_EVENT_TRACE(hdcp, event);
448 	memset(output, 0, sizeof(struct mod_hdcp_output));
449 	memset(&event_ctx, 0, sizeof(struct mod_hdcp_event_context));
450 	event_ctx.event = event;
451 
452 	/* execute and transition */
453 	exec_status = execution(hdcp, &event_ctx, &hdcp->auth.trans_input);
454 	trans_status = transition(
455 			hdcp, &event_ctx, &hdcp->auth.trans_input, output);
456 	if (trans_status == MOD_HDCP_STATUS_SUCCESS) {
457 		status = MOD_HDCP_STATUS_SUCCESS;
458 	} else if (exec_status == MOD_HDCP_STATUS_SUCCESS) {
459 		status = MOD_HDCP_STATUS_INTERNAL_POLICY_FAILURE;
460 		push_error_status(hdcp, status);
461 	} else {
462 		status = exec_status;
463 		push_error_status(hdcp, status);
464 	}
465 
466 	/* reset authentication if needed */
467 	if (trans_status == MOD_HDCP_STATUS_RESET_NEEDED) {
468 		HDCP_FULL_DDC_TRACE(hdcp);
469 		reset_status = reset_authentication(hdcp, output);
470 		if (reset_status != MOD_HDCP_STATUS_SUCCESS)
471 			push_error_status(hdcp, reset_status);
472 	}
473 	return status;
474 }
475 
476 enum mod_hdcp_operation_mode mod_hdcp_signal_type_to_operation_mode(
477 		enum signal_type signal)
478 {
479 	enum mod_hdcp_operation_mode mode = MOD_HDCP_MODE_OFF;
480 
481 	switch (signal) {
482 	case SIGNAL_TYPE_DVI_SINGLE_LINK:
483 	case SIGNAL_TYPE_HDMI_TYPE_A:
484 		mode = MOD_HDCP_MODE_DEFAULT;
485 		break;
486 	case SIGNAL_TYPE_EDP:
487 	case SIGNAL_TYPE_DISPLAY_PORT:
488 	case SIGNAL_TYPE_DISPLAY_PORT_MST:
489 		mode = MOD_HDCP_MODE_DP;
490 		break;
491 	default:
492 		break;
493 	}
494 
495 	return mode;
496 }
497