xref: /linux/drivers/gpu/drm/i915/display/intel_dp_hdcp.c (revision ad36a322619c14ba35872129a401ee214bfad875)
1 /* SPDX-License-Identifier: MIT */
2 /*
3  * Copyright (C) 2020 Google, Inc.
4  *
5  * Authors:
6  * Sean Paul <seanpaul@chromium.org>
7  */
8 
9 #include <drm/display/drm_dp_helper.h>
10 #include <drm/display/drm_dp_mst_helper.h>
11 #include <drm/display/drm_hdcp_helper.h>
12 #include <drm/drm_print.h>
13 
14 #include "i915_reg.h"
15 #include "intel_ddi.h"
16 #include "intel_de.h"
17 #include "intel_display_types.h"
18 #include "intel_dp.h"
19 #include "intel_dp_hdcp.h"
20 #include "intel_hdcp.h"
21 #include "intel_hdcp_regs.h"
22 #include "intel_hdcp_shim.h"
23 
24 static u32 transcoder_to_stream_enc_status(enum transcoder cpu_transcoder)
25 {
26 	switch (cpu_transcoder) {
27 	case TRANSCODER_A:
28 		return HDCP_STATUS_STREAM_A_ENC;
29 	case TRANSCODER_B:
30 		return HDCP_STATUS_STREAM_B_ENC;
31 	case TRANSCODER_C:
32 		return HDCP_STATUS_STREAM_C_ENC;
33 	case TRANSCODER_D:
34 		return HDCP_STATUS_STREAM_D_ENC;
35 	default:
36 		return 0;
37 	}
38 }
39 
40 static void intel_dp_hdcp_wait_for_cp_irq(struct intel_connector *connector,
41 					  int timeout)
42 {
43 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
44 	struct intel_dp *dp = &dig_port->dp;
45 	struct intel_hdcp *hdcp = &dp->attached_connector->hdcp;
46 	long ret;
47 
48 #define C (hdcp->cp_irq_count_cached != atomic_read(&hdcp->cp_irq_count))
49 	ret = wait_event_interruptible_timeout(hdcp->cp_irq_queue, C,
50 					       msecs_to_jiffies(timeout));
51 
52 	if (!ret)
53 		drm_dbg_kms(connector->base.dev,
54 			    "Timedout at waiting for CP_IRQ\n");
55 }
56 
57 static
58 int intel_dp_hdcp_write_an_aksv(struct intel_digital_port *dig_port,
59 				u8 *an)
60 {
61 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
62 	u8 aksv[DRM_HDCP_KSV_LEN] = {};
63 	ssize_t dpcd_ret;
64 
65 	/* Output An first, that's easy */
66 	dpcd_ret = drm_dp_dpcd_write(&dig_port->dp.aux, DP_AUX_HDCP_AN,
67 				     an, DRM_HDCP_AN_LEN);
68 	if (dpcd_ret != DRM_HDCP_AN_LEN) {
69 		drm_dbg_kms(&i915->drm,
70 			    "Failed to write An over DP/AUX (%zd)\n",
71 			    dpcd_ret);
72 		return dpcd_ret >= 0 ? -EIO : dpcd_ret;
73 	}
74 
75 	/*
76 	 * Since Aksv is Oh-So-Secret, we can't access it in software. So we
77 	 * send an empty buffer of the correct length through the DP helpers. On
78 	 * the other side, in the transfer hook, we'll generate a flag based on
79 	 * the destination address which will tickle the hardware to output the
80 	 * Aksv on our behalf after the header is sent.
81 	 */
82 	dpcd_ret = drm_dp_dpcd_write(&dig_port->dp.aux, DP_AUX_HDCP_AKSV,
83 				     aksv, DRM_HDCP_KSV_LEN);
84 	if (dpcd_ret != DRM_HDCP_KSV_LEN) {
85 		drm_dbg_kms(&i915->drm,
86 			    "Failed to write Aksv over DP/AUX (%zd)\n",
87 			    dpcd_ret);
88 		return dpcd_ret >= 0 ? -EIO : dpcd_ret;
89 	}
90 	return 0;
91 }
92 
93 static int intel_dp_hdcp_read_bksv(struct intel_digital_port *dig_port,
94 				   u8 *bksv)
95 {
96 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
97 	ssize_t ret;
98 
99 	ret = drm_dp_dpcd_read(&dig_port->dp.aux, DP_AUX_HDCP_BKSV, bksv,
100 			       DRM_HDCP_KSV_LEN);
101 	if (ret != DRM_HDCP_KSV_LEN) {
102 		drm_dbg_kms(&i915->drm,
103 			    "Read Bksv from DP/AUX failed (%zd)\n", ret);
104 		return ret >= 0 ? -EIO : ret;
105 	}
106 	return 0;
107 }
108 
109 static int intel_dp_hdcp_read_bstatus(struct intel_digital_port *dig_port,
110 				      u8 *bstatus)
111 {
112 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
113 	ssize_t ret;
114 
115 	/*
116 	 * For some reason the HDMI and DP HDCP specs call this register
117 	 * definition by different names. In the HDMI spec, it's called BSTATUS,
118 	 * but in DP it's called BINFO.
119 	 */
120 	ret = drm_dp_dpcd_read(&dig_port->dp.aux, DP_AUX_HDCP_BINFO,
121 			       bstatus, DRM_HDCP_BSTATUS_LEN);
122 	if (ret != DRM_HDCP_BSTATUS_LEN) {
123 		drm_dbg_kms(&i915->drm,
124 			    "Read bstatus from DP/AUX failed (%zd)\n", ret);
125 		return ret >= 0 ? -EIO : ret;
126 	}
127 	return 0;
128 }
129 
130 static
131 int intel_dp_hdcp_read_bcaps(struct drm_dp_aux *aux,
132 			     struct drm_i915_private *i915,
133 			     u8 *bcaps)
134 {
135 	ssize_t ret;
136 
137 	ret = drm_dp_dpcd_read(aux, DP_AUX_HDCP_BCAPS,
138 			       bcaps, 1);
139 	if (ret != 1) {
140 		drm_dbg_kms(&i915->drm,
141 			    "Read bcaps from DP/AUX failed (%zd)\n", ret);
142 		return ret >= 0 ? -EIO : ret;
143 	}
144 
145 	return 0;
146 }
147 
148 static
149 int intel_dp_hdcp_repeater_present(struct intel_digital_port *dig_port,
150 				   bool *repeater_present)
151 {
152 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
153 	ssize_t ret;
154 	u8 bcaps;
155 
156 	ret = intel_dp_hdcp_read_bcaps(&dig_port->dp.aux, i915, &bcaps);
157 	if (ret)
158 		return ret;
159 
160 	*repeater_present = bcaps & DP_BCAPS_REPEATER_PRESENT;
161 	return 0;
162 }
163 
164 static
165 int intel_dp_hdcp_read_ri_prime(struct intel_digital_port *dig_port,
166 				u8 *ri_prime)
167 {
168 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
169 	ssize_t ret;
170 
171 	ret = drm_dp_dpcd_read(&dig_port->dp.aux, DP_AUX_HDCP_RI_PRIME,
172 			       ri_prime, DRM_HDCP_RI_LEN);
173 	if (ret != DRM_HDCP_RI_LEN) {
174 		drm_dbg_kms(&i915->drm, "Read Ri' from DP/AUX failed (%zd)\n",
175 			    ret);
176 		return ret >= 0 ? -EIO : ret;
177 	}
178 	return 0;
179 }
180 
181 static
182 int intel_dp_hdcp_read_ksv_ready(struct intel_digital_port *dig_port,
183 				 bool *ksv_ready)
184 {
185 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
186 	ssize_t ret;
187 	u8 bstatus;
188 
189 	ret = drm_dp_dpcd_read(&dig_port->dp.aux, DP_AUX_HDCP_BSTATUS,
190 			       &bstatus, 1);
191 	if (ret != 1) {
192 		drm_dbg_kms(&i915->drm,
193 			    "Read bstatus from DP/AUX failed (%zd)\n", ret);
194 		return ret >= 0 ? -EIO : ret;
195 	}
196 	*ksv_ready = bstatus & DP_BSTATUS_READY;
197 	return 0;
198 }
199 
200 static
201 int intel_dp_hdcp_read_ksv_fifo(struct intel_digital_port *dig_port,
202 				int num_downstream, u8 *ksv_fifo)
203 {
204 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
205 	ssize_t ret;
206 	int i;
207 
208 	/* KSV list is read via 15 byte window (3 entries @ 5 bytes each) */
209 	for (i = 0; i < num_downstream; i += 3) {
210 		size_t len = min(num_downstream - i, 3) * DRM_HDCP_KSV_LEN;
211 		ret = drm_dp_dpcd_read(&dig_port->dp.aux,
212 				       DP_AUX_HDCP_KSV_FIFO,
213 				       ksv_fifo + i * DRM_HDCP_KSV_LEN,
214 				       len);
215 		if (ret != len) {
216 			drm_dbg_kms(&i915->drm,
217 				    "Read ksv[%d] from DP/AUX failed (%zd)\n",
218 				    i, ret);
219 			return ret >= 0 ? -EIO : ret;
220 		}
221 	}
222 	return 0;
223 }
224 
225 static
226 int intel_dp_hdcp_read_v_prime_part(struct intel_digital_port *dig_port,
227 				    int i, u32 *part)
228 {
229 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
230 	ssize_t ret;
231 
232 	if (i >= DRM_HDCP_V_PRIME_NUM_PARTS)
233 		return -EINVAL;
234 
235 	ret = drm_dp_dpcd_read(&dig_port->dp.aux,
236 			       DP_AUX_HDCP_V_PRIME(i), part,
237 			       DRM_HDCP_V_PRIME_PART_LEN);
238 	if (ret != DRM_HDCP_V_PRIME_PART_LEN) {
239 		drm_dbg_kms(&i915->drm,
240 			    "Read v'[%d] from DP/AUX failed (%zd)\n", i, ret);
241 		return ret >= 0 ? -EIO : ret;
242 	}
243 	return 0;
244 }
245 
246 static
247 int intel_dp_hdcp_toggle_signalling(struct intel_digital_port *dig_port,
248 				    enum transcoder cpu_transcoder,
249 				    bool enable)
250 {
251 	/* Not used for single stream DisplayPort setups */
252 	return 0;
253 }
254 
255 static
256 bool intel_dp_hdcp_check_link(struct intel_digital_port *dig_port,
257 			      struct intel_connector *connector)
258 {
259 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
260 	ssize_t ret;
261 	u8 bstatus;
262 
263 	ret = drm_dp_dpcd_read(&dig_port->dp.aux, DP_AUX_HDCP_BSTATUS,
264 			       &bstatus, 1);
265 	if (ret != 1) {
266 		drm_dbg_kms(&i915->drm,
267 			    "Read bstatus from DP/AUX failed (%zd)\n", ret);
268 		return false;
269 	}
270 
271 	return !(bstatus & (DP_BSTATUS_LINK_FAILURE | DP_BSTATUS_REAUTH_REQ));
272 }
273 
274 static
275 int intel_dp_hdcp_get_capability(struct intel_digital_port *dig_port,
276 				 bool *hdcp_capable)
277 {
278 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
279 	ssize_t ret;
280 	u8 bcaps;
281 
282 	ret = intel_dp_hdcp_read_bcaps(&dig_port->dp.aux, i915, &bcaps);
283 	if (ret)
284 		return ret;
285 
286 	*hdcp_capable = bcaps & DP_BCAPS_HDCP_CAPABLE;
287 	return 0;
288 }
289 
290 struct hdcp2_dp_errata_stream_type {
291 	u8	msg_id;
292 	u8	stream_type;
293 } __packed;
294 
295 struct hdcp2_dp_msg_data {
296 	u8 msg_id;
297 	u32 offset;
298 	bool msg_detectable;
299 	u32 timeout;
300 	u32 timeout2; /* Added for non_paired situation */
301 	/* Timeout to read entire msg */
302 	u32 msg_read_timeout;
303 };
304 
305 static const struct hdcp2_dp_msg_data hdcp2_dp_msg_data[] = {
306 	{ HDCP_2_2_AKE_INIT, DP_HDCP_2_2_AKE_INIT_OFFSET, false, 0, 0, 0},
307 	{ HDCP_2_2_AKE_SEND_CERT, DP_HDCP_2_2_AKE_SEND_CERT_OFFSET,
308 	  false, HDCP_2_2_CERT_TIMEOUT_MS, 0, HDCP_2_2_DP_CERT_READ_TIMEOUT_MS},
309 	{ HDCP_2_2_AKE_NO_STORED_KM, DP_HDCP_2_2_AKE_NO_STORED_KM_OFFSET,
310 	  false, 0, 0, 0 },
311 	{ HDCP_2_2_AKE_STORED_KM, DP_HDCP_2_2_AKE_STORED_KM_OFFSET,
312 	  false, 0, 0, 0 },
313 	{ HDCP_2_2_AKE_SEND_HPRIME, DP_HDCP_2_2_AKE_SEND_HPRIME_OFFSET,
314 	  true, HDCP_2_2_HPRIME_PAIRED_TIMEOUT_MS,
315 	  HDCP_2_2_HPRIME_NO_PAIRED_TIMEOUT_MS, HDCP_2_2_DP_HPRIME_READ_TIMEOUT_MS},
316 	{ HDCP_2_2_AKE_SEND_PAIRING_INFO,
317 	  DP_HDCP_2_2_AKE_SEND_PAIRING_INFO_OFFSET, true,
318 	  HDCP_2_2_PAIRING_TIMEOUT_MS, 0, HDCP_2_2_DP_PAIRING_READ_TIMEOUT_MS },
319 	{ HDCP_2_2_LC_INIT, DP_HDCP_2_2_LC_INIT_OFFSET, false, 0, 0, 0 },
320 	{ HDCP_2_2_LC_SEND_LPRIME, DP_HDCP_2_2_LC_SEND_LPRIME_OFFSET,
321 	  false, HDCP_2_2_DP_LPRIME_TIMEOUT_MS, 0, 0 },
322 	{ HDCP_2_2_SKE_SEND_EKS, DP_HDCP_2_2_SKE_SEND_EKS_OFFSET, false,
323 	  0, 0, 0 },
324 	{ HDCP_2_2_REP_SEND_RECVID_LIST,
325 	  DP_HDCP_2_2_REP_SEND_RECVID_LIST_OFFSET, true,
326 	  HDCP_2_2_RECVID_LIST_TIMEOUT_MS, 0, 0 },
327 	{ HDCP_2_2_REP_SEND_ACK, DP_HDCP_2_2_REP_SEND_ACK_OFFSET, false,
328 	  0, 0, 0 },
329 	{ HDCP_2_2_REP_STREAM_MANAGE,
330 	  DP_HDCP_2_2_REP_STREAM_MANAGE_OFFSET, false,
331 	  0, 0, 0},
332 	{ HDCP_2_2_REP_STREAM_READY, DP_HDCP_2_2_REP_STREAM_READY_OFFSET,
333 	  false, HDCP_2_2_STREAM_READY_TIMEOUT_MS, 0, 0 },
334 /* local define to shovel this through the write_2_2 interface */
335 #define HDCP_2_2_ERRATA_DP_STREAM_TYPE	50
336 	{ HDCP_2_2_ERRATA_DP_STREAM_TYPE,
337 	  DP_HDCP_2_2_REG_STREAM_TYPE_OFFSET, false,
338 	  0, 0 },
339 };
340 
341 static int
342 intel_dp_hdcp2_read_rx_status(struct intel_connector *connector,
343 			      u8 *rx_status)
344 {
345 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
346 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
347 	struct drm_dp_aux *aux = &dig_port->dp.aux;
348 	ssize_t ret;
349 
350 	ret = drm_dp_dpcd_read(aux,
351 			       DP_HDCP_2_2_REG_RXSTATUS_OFFSET, rx_status,
352 			       HDCP_2_2_DP_RXSTATUS_LEN);
353 	if (ret != HDCP_2_2_DP_RXSTATUS_LEN) {
354 		drm_dbg_kms(&i915->drm,
355 			    "Read bstatus from DP/AUX failed (%zd)\n", ret);
356 		return ret >= 0 ? -EIO : ret;
357 	}
358 
359 	return 0;
360 }
361 
362 static
363 int hdcp2_detect_msg_availability(struct intel_connector *connector,
364 				  u8 msg_id, bool *msg_ready)
365 {
366 	u8 rx_status;
367 	int ret;
368 
369 	*msg_ready = false;
370 	ret = intel_dp_hdcp2_read_rx_status(connector, &rx_status);
371 	if (ret < 0)
372 		return ret;
373 
374 	switch (msg_id) {
375 	case HDCP_2_2_AKE_SEND_HPRIME:
376 		if (HDCP_2_2_DP_RXSTATUS_H_PRIME(rx_status))
377 			*msg_ready = true;
378 		break;
379 	case HDCP_2_2_AKE_SEND_PAIRING_INFO:
380 		if (HDCP_2_2_DP_RXSTATUS_PAIRING(rx_status))
381 			*msg_ready = true;
382 		break;
383 	case HDCP_2_2_REP_SEND_RECVID_LIST:
384 		if (HDCP_2_2_DP_RXSTATUS_READY(rx_status))
385 			*msg_ready = true;
386 		break;
387 	default:
388 		drm_err(connector->base.dev,
389 			"Unidentified msg_id: %d\n", msg_id);
390 		return -EINVAL;
391 	}
392 
393 	return 0;
394 }
395 
396 static ssize_t
397 intel_dp_hdcp2_wait_for_msg(struct intel_connector *connector,
398 			    const struct hdcp2_dp_msg_data *hdcp2_msg_data)
399 {
400 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
401 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
402 	struct intel_dp *dp = &dig_port->dp;
403 	struct intel_hdcp *hdcp = &dp->attached_connector->hdcp;
404 	u8 msg_id = hdcp2_msg_data->msg_id;
405 	int ret, timeout;
406 	bool msg_ready = false;
407 
408 	if (msg_id == HDCP_2_2_AKE_SEND_HPRIME && !hdcp->is_paired)
409 		timeout = hdcp2_msg_data->timeout2;
410 	else
411 		timeout = hdcp2_msg_data->timeout;
412 
413 	/*
414 	 * There is no way to detect the CERT, LPRIME and STREAM_READY
415 	 * availability. So Wait for timeout and read the msg.
416 	 */
417 	if (!hdcp2_msg_data->msg_detectable) {
418 		mdelay(timeout);
419 		ret = 0;
420 	} else {
421 		/*
422 		 * As we want to check the msg availability at timeout, Ignoring
423 		 * the timeout at wait for CP_IRQ.
424 		 */
425 		intel_dp_hdcp_wait_for_cp_irq(connector, timeout);
426 		ret = hdcp2_detect_msg_availability(connector, msg_id,
427 						    &msg_ready);
428 		if (!msg_ready)
429 			ret = -ETIMEDOUT;
430 	}
431 
432 	if (ret)
433 		drm_dbg_kms(&i915->drm,
434 			    "msg_id %d, ret %d, timeout(mSec): %d\n",
435 			    hdcp2_msg_data->msg_id, ret, timeout);
436 
437 	return ret;
438 }
439 
440 static const struct hdcp2_dp_msg_data *get_hdcp2_dp_msg_data(u8 msg_id)
441 {
442 	int i;
443 
444 	for (i = 0; i < ARRAY_SIZE(hdcp2_dp_msg_data); i++)
445 		if (hdcp2_dp_msg_data[i].msg_id == msg_id)
446 			return &hdcp2_dp_msg_data[i];
447 
448 	return NULL;
449 }
450 
451 static
452 int intel_dp_hdcp2_write_msg(struct intel_connector *connector,
453 			     void *buf, size_t size)
454 {
455 	unsigned int offset;
456 	u8 *byte = buf;
457 	ssize_t ret, bytes_to_write, len;
458 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
459 	struct drm_dp_aux *aux = &dig_port->dp.aux;
460 	const struct hdcp2_dp_msg_data *hdcp2_msg_data;
461 
462 	hdcp2_msg_data = get_hdcp2_dp_msg_data(*byte);
463 	if (!hdcp2_msg_data)
464 		return -EINVAL;
465 
466 	offset = hdcp2_msg_data->offset;
467 
468 	/* No msg_id in DP HDCP2.2 msgs */
469 	bytes_to_write = size - 1;
470 	byte++;
471 
472 	while (bytes_to_write) {
473 		len = bytes_to_write > DP_AUX_MAX_PAYLOAD_BYTES ?
474 				DP_AUX_MAX_PAYLOAD_BYTES : bytes_to_write;
475 
476 		ret = drm_dp_dpcd_write(aux,
477 					offset, (void *)byte, len);
478 		if (ret < 0)
479 			return ret;
480 
481 		bytes_to_write -= ret;
482 		byte += ret;
483 		offset += ret;
484 	}
485 
486 	return size;
487 }
488 
489 static
490 ssize_t get_receiver_id_list_rx_info(struct intel_connector *connector,
491 				     u32 *dev_cnt, u8 *byte)
492 {
493 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
494 	struct drm_dp_aux *aux = &dig_port->dp.aux;
495 	ssize_t ret;
496 	u8 *rx_info = byte;
497 
498 	ret = drm_dp_dpcd_read(aux,
499 			       DP_HDCP_2_2_REG_RXINFO_OFFSET,
500 			       (void *)rx_info, HDCP_2_2_RXINFO_LEN);
501 	if (ret != HDCP_2_2_RXINFO_LEN)
502 		return ret >= 0 ? -EIO : ret;
503 
504 	*dev_cnt = (HDCP_2_2_DEV_COUNT_HI(rx_info[0]) << 4 |
505 		   HDCP_2_2_DEV_COUNT_LO(rx_info[1]));
506 
507 	if (*dev_cnt > HDCP_2_2_MAX_DEVICE_COUNT)
508 		*dev_cnt = HDCP_2_2_MAX_DEVICE_COUNT;
509 
510 	return ret;
511 }
512 
513 static
514 int intel_dp_hdcp2_read_msg(struct intel_connector *connector,
515 			    u8 msg_id, void *buf, size_t size)
516 {
517 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
518 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
519 	struct drm_dp_aux *aux = &dig_port->dp.aux;
520 	struct intel_dp *dp = &dig_port->dp;
521 	struct intel_hdcp *hdcp = &dp->attached_connector->hdcp;
522 	unsigned int offset;
523 	u8 *byte = buf;
524 	ssize_t ret, bytes_to_recv, len;
525 	const struct hdcp2_dp_msg_data *hdcp2_msg_data;
526 	ktime_t msg_end = ktime_set(0, 0);
527 	bool msg_expired;
528 	u32 dev_cnt;
529 
530 	hdcp2_msg_data = get_hdcp2_dp_msg_data(msg_id);
531 	if (!hdcp2_msg_data)
532 		return -EINVAL;
533 	offset = hdcp2_msg_data->offset;
534 
535 	ret = intel_dp_hdcp2_wait_for_msg(connector, hdcp2_msg_data);
536 	if (ret < 0)
537 		return ret;
538 
539 	hdcp->cp_irq_count_cached = atomic_read(&hdcp->cp_irq_count);
540 
541 	/* DP adaptation msgs has no msg_id */
542 	byte++;
543 
544 	if (msg_id == HDCP_2_2_REP_SEND_RECVID_LIST) {
545 		ret = get_receiver_id_list_rx_info(connector, &dev_cnt, byte);
546 		if (ret < 0)
547 			return ret;
548 
549 		byte += ret;
550 		size = sizeof(struct hdcp2_rep_send_receiverid_list) -
551 		HDCP_2_2_RXINFO_LEN - HDCP_2_2_RECEIVER_IDS_MAX_LEN +
552 		(dev_cnt * HDCP_2_2_RECEIVER_ID_LEN);
553 		offset += HDCP_2_2_RXINFO_LEN;
554 	}
555 
556 	bytes_to_recv = size - 1;
557 
558 	while (bytes_to_recv) {
559 		len = bytes_to_recv > DP_AUX_MAX_PAYLOAD_BYTES ?
560 		      DP_AUX_MAX_PAYLOAD_BYTES : bytes_to_recv;
561 
562 		/* Entire msg read timeout since initiate of msg read */
563 		if (bytes_to_recv == size - 1 && hdcp2_msg_data->msg_read_timeout > 0) {
564 			msg_end = ktime_add_ms(ktime_get_raw(),
565 					       hdcp2_msg_data->msg_read_timeout);
566 		}
567 
568 		ret = drm_dp_dpcd_read(aux, offset,
569 				       (void *)byte, len);
570 		if (ret < 0) {
571 			drm_dbg_kms(&i915->drm, "msg_id %d, ret %zd\n",
572 				    msg_id, ret);
573 			return ret;
574 		}
575 
576 		bytes_to_recv -= ret;
577 		byte += ret;
578 		offset += ret;
579 	}
580 
581 	if (hdcp2_msg_data->msg_read_timeout > 0) {
582 		msg_expired = ktime_after(ktime_get_raw(), msg_end);
583 		if (msg_expired) {
584 			drm_dbg_kms(&i915->drm, "msg_id %d, entire msg read timeout(mSec): %d\n",
585 				    msg_id, hdcp2_msg_data->msg_read_timeout);
586 			return -ETIMEDOUT;
587 		}
588 	}
589 
590 	byte = buf;
591 	*byte = msg_id;
592 
593 	return size;
594 }
595 
596 static
597 int intel_dp_hdcp2_config_stream_type(struct intel_connector *connector,
598 				      bool is_repeater, u8 content_type)
599 {
600 	int ret;
601 	struct hdcp2_dp_errata_stream_type stream_type_msg;
602 
603 	if (is_repeater)
604 		return 0;
605 
606 	/*
607 	 * Errata for DP: As Stream type is used for encryption, Receiver
608 	 * should be communicated with stream type for the decryption of the
609 	 * content.
610 	 * Repeater will be communicated with stream type as a part of it's
611 	 * auth later in time.
612 	 */
613 	stream_type_msg.msg_id = HDCP_2_2_ERRATA_DP_STREAM_TYPE;
614 	stream_type_msg.stream_type = content_type;
615 
616 	ret =  intel_dp_hdcp2_write_msg(connector, &stream_type_msg,
617 					sizeof(stream_type_msg));
618 
619 	return ret < 0 ? ret : 0;
620 
621 }
622 
623 static
624 int intel_dp_hdcp2_check_link(struct intel_digital_port *dig_port,
625 			      struct intel_connector *connector)
626 {
627 	u8 rx_status;
628 	int ret;
629 
630 	ret = intel_dp_hdcp2_read_rx_status(connector,
631 					    &rx_status);
632 	if (ret)
633 		return ret;
634 
635 	if (HDCP_2_2_DP_RXSTATUS_REAUTH_REQ(rx_status))
636 		ret = HDCP_REAUTH_REQUEST;
637 	else if (HDCP_2_2_DP_RXSTATUS_LINK_FAILED(rx_status))
638 		ret = HDCP_LINK_INTEGRITY_FAILURE;
639 	else if (HDCP_2_2_DP_RXSTATUS_READY(rx_status))
640 		ret = HDCP_TOPOLOGY_CHANGE;
641 
642 	return ret;
643 }
644 
645 static
646 int _intel_dp_hdcp2_get_capability(struct drm_dp_aux *aux,
647 				   bool *capable)
648 {
649 	u8 rx_caps[3];
650 	int ret, i;
651 
652 	*capable = false;
653 
654 	/*
655 	 * Some HDCP monitors act really shady by not giving the correct hdcp
656 	 * capability on the first rx_caps read and usually take an extra read
657 	 * to give the capability. We read rx_caps three times before we
658 	 * declare a monitor not capable of HDCP 2.2.
659 	 */
660 	for (i = 0; i < 3; i++) {
661 		ret = drm_dp_dpcd_read(aux,
662 				       DP_HDCP_2_2_REG_RX_CAPS_OFFSET,
663 				       rx_caps, HDCP_2_2_RXCAPS_LEN);
664 		if (ret != HDCP_2_2_RXCAPS_LEN)
665 			return ret >= 0 ? -EIO : ret;
666 
667 		if (rx_caps[0] == HDCP_2_2_RX_CAPS_VERSION_VAL &&
668 		    HDCP_2_2_DP_HDCP_CAPABLE(rx_caps[2])) {
669 			*capable = true;
670 			break;
671 		}
672 	}
673 
674 	return 0;
675 }
676 
677 static
678 int intel_dp_hdcp2_get_capability(struct intel_connector *connector,
679 				  bool *capable)
680 {
681 	struct intel_digital_port *dig_port;
682 	struct drm_dp_aux *aux;
683 
684 	*capable = false;
685 	if (!intel_attached_encoder(connector))
686 		return -EINVAL;
687 
688 	dig_port = intel_attached_dig_port(connector);
689 	aux = &dig_port->dp.aux;
690 
691 	return _intel_dp_hdcp2_get_capability(aux, capable);
692 }
693 
694 static
695 int intel_dp_hdcp_get_remote_capability(struct intel_connector *connector,
696 					bool *hdcp_capable,
697 					bool *hdcp2_capable)
698 {
699 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
700 	struct drm_dp_aux *aux;
701 	u8 bcaps;
702 	int ret;
703 
704 	*hdcp_capable = false;
705 	*hdcp2_capable = false;
706 	if (!connector->mst_port)
707 		return -EINVAL;
708 
709 	aux = &connector->port->aux;
710 	ret =  _intel_dp_hdcp2_get_capability(aux, hdcp2_capable);
711 	if (ret)
712 		drm_dbg_kms(&i915->drm,
713 			    "HDCP2 DPCD capability read failed err: %d\n", ret);
714 
715 	ret = intel_dp_hdcp_read_bcaps(aux, i915, &bcaps);
716 	if (ret)
717 		return ret;
718 
719 	*hdcp_capable = bcaps & DP_BCAPS_HDCP_CAPABLE;
720 
721 	return 0;
722 }
723 
724 static const struct intel_hdcp_shim intel_dp_hdcp_shim = {
725 	.write_an_aksv = intel_dp_hdcp_write_an_aksv,
726 	.read_bksv = intel_dp_hdcp_read_bksv,
727 	.read_bstatus = intel_dp_hdcp_read_bstatus,
728 	.repeater_present = intel_dp_hdcp_repeater_present,
729 	.read_ri_prime = intel_dp_hdcp_read_ri_prime,
730 	.read_ksv_ready = intel_dp_hdcp_read_ksv_ready,
731 	.read_ksv_fifo = intel_dp_hdcp_read_ksv_fifo,
732 	.read_v_prime_part = intel_dp_hdcp_read_v_prime_part,
733 	.toggle_signalling = intel_dp_hdcp_toggle_signalling,
734 	.check_link = intel_dp_hdcp_check_link,
735 	.hdcp_get_capability = intel_dp_hdcp_get_capability,
736 	.write_2_2_msg = intel_dp_hdcp2_write_msg,
737 	.read_2_2_msg = intel_dp_hdcp2_read_msg,
738 	.config_stream_type = intel_dp_hdcp2_config_stream_type,
739 	.check_2_2_link = intel_dp_hdcp2_check_link,
740 	.hdcp_2_2_get_capability = intel_dp_hdcp2_get_capability,
741 	.protocol = HDCP_PROTOCOL_DP,
742 };
743 
744 static int
745 intel_dp_mst_toggle_hdcp_stream_select(struct intel_connector *connector,
746 				       bool enable)
747 {
748 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
749 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
750 	struct intel_hdcp *hdcp = &connector->hdcp;
751 	int ret;
752 
753 	ret = intel_ddi_toggle_hdcp_bits(&dig_port->base,
754 					 hdcp->stream_transcoder, enable,
755 					 TRANS_DDI_HDCP_SELECT);
756 	if (ret)
757 		drm_err(&i915->drm, "%s HDCP stream select failed (%d)\n",
758 			enable ? "Enable" : "Disable", ret);
759 	return ret;
760 }
761 
762 static int
763 intel_dp_mst_hdcp_stream_encryption(struct intel_connector *connector,
764 				    bool enable)
765 {
766 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
767 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
768 	struct intel_hdcp *hdcp = &connector->hdcp;
769 	enum port port = dig_port->base.port;
770 	enum transcoder cpu_transcoder = hdcp->stream_transcoder;
771 	u32 stream_enc_status;
772 	int ret;
773 
774 	ret = intel_dp_mst_toggle_hdcp_stream_select(connector, enable);
775 	if (ret)
776 		return ret;
777 
778 	stream_enc_status =  transcoder_to_stream_enc_status(cpu_transcoder);
779 	if (!stream_enc_status)
780 		return -EINVAL;
781 
782 	/* Wait for encryption confirmation */
783 	if (intel_de_wait(i915, HDCP_STATUS(i915, cpu_transcoder, port),
784 			  stream_enc_status, enable ? stream_enc_status : 0,
785 			  HDCP_ENCRYPT_STATUS_CHANGE_TIMEOUT_MS)) {
786 		drm_err(&i915->drm, "Timed out waiting for transcoder: %s stream encryption %s\n",
787 			transcoder_name(cpu_transcoder), enable ? "enabled" : "disabled");
788 		return -ETIMEDOUT;
789 	}
790 
791 	return 0;
792 }
793 
794 static int
795 intel_dp_mst_hdcp2_stream_encryption(struct intel_connector *connector,
796 				     bool enable)
797 {
798 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
799 	struct drm_i915_private *i915 = to_i915(connector->base.dev);
800 	struct hdcp_port_data *data = &dig_port->hdcp_port_data;
801 	struct intel_hdcp *hdcp = &connector->hdcp;
802 	enum transcoder cpu_transcoder = hdcp->stream_transcoder;
803 	enum pipe pipe = (enum pipe)cpu_transcoder;
804 	enum port port = dig_port->base.port;
805 	int ret;
806 
807 	drm_WARN_ON(&i915->drm, enable &&
808 		    !!(intel_de_read(i915, HDCP2_AUTH_STREAM(i915, cpu_transcoder, port))
809 		    & AUTH_STREAM_TYPE) != data->streams[0].stream_type);
810 
811 	ret = intel_dp_mst_toggle_hdcp_stream_select(connector, enable);
812 	if (ret)
813 		return ret;
814 
815 	/* Wait for encryption confirmation */
816 	if (intel_de_wait(i915, HDCP2_STREAM_STATUS(i915, cpu_transcoder, pipe),
817 			  STREAM_ENCRYPTION_STATUS,
818 			  enable ? STREAM_ENCRYPTION_STATUS : 0,
819 			  HDCP_ENCRYPT_STATUS_CHANGE_TIMEOUT_MS)) {
820 		drm_err(&i915->drm, "Timed out waiting for transcoder: %s stream encryption %s\n",
821 			transcoder_name(cpu_transcoder), enable ? "enabled" : "disabled");
822 		return -ETIMEDOUT;
823 	}
824 
825 	return 0;
826 }
827 
828 static
829 int intel_dp_mst_hdcp2_check_link(struct intel_digital_port *dig_port,
830 				  struct intel_connector *connector)
831 {
832 	struct intel_hdcp *hdcp = &connector->hdcp;
833 	int ret;
834 
835 	/*
836 	 * We do need to do the Link Check only for the connector involved with
837 	 * HDCP port authentication and encryption.
838 	 * We can re-use the hdcp->is_repeater flag to know that the connector
839 	 * involved with HDCP port authentication and encryption.
840 	 */
841 	if (hdcp->is_repeater) {
842 		ret = intel_dp_hdcp2_check_link(dig_port, connector);
843 		if (ret)
844 			return ret;
845 	}
846 
847 	return 0;
848 }
849 
850 static const struct intel_hdcp_shim intel_dp_mst_hdcp_shim = {
851 	.write_an_aksv = intel_dp_hdcp_write_an_aksv,
852 	.read_bksv = intel_dp_hdcp_read_bksv,
853 	.read_bstatus = intel_dp_hdcp_read_bstatus,
854 	.repeater_present = intel_dp_hdcp_repeater_present,
855 	.read_ri_prime = intel_dp_hdcp_read_ri_prime,
856 	.read_ksv_ready = intel_dp_hdcp_read_ksv_ready,
857 	.read_ksv_fifo = intel_dp_hdcp_read_ksv_fifo,
858 	.read_v_prime_part = intel_dp_hdcp_read_v_prime_part,
859 	.toggle_signalling = intel_dp_hdcp_toggle_signalling,
860 	.stream_encryption = intel_dp_mst_hdcp_stream_encryption,
861 	.check_link = intel_dp_hdcp_check_link,
862 	.hdcp_get_capability = intel_dp_hdcp_get_capability,
863 	.write_2_2_msg = intel_dp_hdcp2_write_msg,
864 	.read_2_2_msg = intel_dp_hdcp2_read_msg,
865 	.config_stream_type = intel_dp_hdcp2_config_stream_type,
866 	.stream_2_2_encryption = intel_dp_mst_hdcp2_stream_encryption,
867 	.check_2_2_link = intel_dp_mst_hdcp2_check_link,
868 	.hdcp_2_2_get_capability = intel_dp_hdcp2_get_capability,
869 	.get_remote_hdcp_capability = intel_dp_hdcp_get_remote_capability,
870 	.protocol = HDCP_PROTOCOL_DP,
871 };
872 
873 int intel_dp_hdcp_init(struct intel_digital_port *dig_port,
874 		       struct intel_connector *intel_connector)
875 {
876 	struct drm_device *dev = intel_connector->base.dev;
877 	struct drm_i915_private *dev_priv = to_i915(dev);
878 	struct intel_encoder *intel_encoder = &dig_port->base;
879 	enum port port = intel_encoder->port;
880 	struct intel_dp *intel_dp = &dig_port->dp;
881 
882 	if (!is_hdcp_supported(dev_priv, port))
883 		return 0;
884 
885 	if (intel_connector->mst_port)
886 		return intel_hdcp_init(intel_connector, dig_port,
887 				       &intel_dp_mst_hdcp_shim);
888 	else if (!intel_dp_is_edp(intel_dp))
889 		return intel_hdcp_init(intel_connector, dig_port,
890 				       &intel_dp_hdcp_shim);
891 
892 	return 0;
893 }
894