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 "amdgpu_dm_hdcp.h" 27 #include "amdgpu.h" 28 #include "amdgpu_dm.h" 29 #include "dm_helpers.h" 30 #include <drm/drm_hdcp.h> 31 #include "hdcp_psp.h" 32 33 /* 34 * If the SRM version being loaded is less than or equal to the 35 * currently loaded SRM, psp will return 0xFFFF as the version 36 */ 37 #define PSP_SRM_VERSION_MAX 0xFFFF 38 39 static bool 40 lp_write_i2c(void *handle, uint32_t address, const uint8_t *data, uint32_t size) 41 { 42 43 struct dc_link *link = handle; 44 struct i2c_payload i2c_payloads[] = {{true, address, size, (void *)data} }; 45 struct i2c_command cmd = {i2c_payloads, 1, I2C_COMMAND_ENGINE_HW, link->dc->caps.i2c_speed_in_khz}; 46 47 return dm_helpers_submit_i2c(link->ctx, link, &cmd); 48 } 49 50 static bool 51 lp_read_i2c(void *handle, uint32_t address, uint8_t offset, uint8_t *data, uint32_t size) 52 { 53 struct dc_link *link = handle; 54 55 struct i2c_payload i2c_payloads[] = {{true, address, 1, &offset}, {false, address, size, data} }; 56 struct i2c_command cmd = {i2c_payloads, 2, I2C_COMMAND_ENGINE_HW, link->dc->caps.i2c_speed_in_khz}; 57 58 return dm_helpers_submit_i2c(link->ctx, link, &cmd); 59 } 60 61 static bool 62 lp_write_dpcd(void *handle, uint32_t address, const uint8_t *data, uint32_t size) 63 { 64 struct dc_link *link = handle; 65 66 return dm_helpers_dp_write_dpcd(link->ctx, link, address, data, size); 67 } 68 69 static bool 70 lp_read_dpcd(void *handle, uint32_t address, uint8_t *data, uint32_t size) 71 { 72 struct dc_link *link = handle; 73 74 return dm_helpers_dp_read_dpcd(link->ctx, link, address, data, size); 75 } 76 77 static uint8_t *psp_get_srm(struct psp_context *psp, uint32_t *srm_version, uint32_t *srm_size) 78 { 79 80 struct ta_hdcp_shared_memory *hdcp_cmd; 81 82 if (!psp->hdcp_context.hdcp_initialized) { 83 DRM_WARN("Failed to get hdcp srm. HDCP TA is not initialized."); 84 return NULL; 85 } 86 87 hdcp_cmd = (struct ta_hdcp_shared_memory *)psp->hdcp_context.hdcp_shared_buf; 88 memset(hdcp_cmd, 0, sizeof(struct ta_hdcp_shared_memory)); 89 90 hdcp_cmd->cmd_id = TA_HDCP_COMMAND__HDCP_GET_SRM; 91 psp_hdcp_invoke(psp, hdcp_cmd->cmd_id); 92 93 if (hdcp_cmd->hdcp_status != TA_HDCP_STATUS__SUCCESS) 94 return NULL; 95 96 *srm_version = hdcp_cmd->out_msg.hdcp_get_srm.srm_version; 97 *srm_size = hdcp_cmd->out_msg.hdcp_get_srm.srm_buf_size; 98 99 100 return hdcp_cmd->out_msg.hdcp_get_srm.srm_buf; 101 } 102 103 static int psp_set_srm(struct psp_context *psp, uint8_t *srm, uint32_t srm_size, uint32_t *srm_version) 104 { 105 106 struct ta_hdcp_shared_memory *hdcp_cmd; 107 108 if (!psp->hdcp_context.hdcp_initialized) { 109 DRM_WARN("Failed to get hdcp srm. HDCP TA is not initialized."); 110 return -EINVAL; 111 } 112 113 hdcp_cmd = (struct ta_hdcp_shared_memory *)psp->hdcp_context.hdcp_shared_buf; 114 memset(hdcp_cmd, 0, sizeof(struct ta_hdcp_shared_memory)); 115 116 memcpy(hdcp_cmd->in_msg.hdcp_set_srm.srm_buf, srm, srm_size); 117 hdcp_cmd->in_msg.hdcp_set_srm.srm_buf_size = srm_size; 118 hdcp_cmd->cmd_id = TA_HDCP_COMMAND__HDCP_SET_SRM; 119 120 psp_hdcp_invoke(psp, hdcp_cmd->cmd_id); 121 122 if (hdcp_cmd->hdcp_status != TA_HDCP_STATUS__SUCCESS || hdcp_cmd->out_msg.hdcp_set_srm.valid_signature != 1 || 123 hdcp_cmd->out_msg.hdcp_set_srm.srm_version == PSP_SRM_VERSION_MAX) 124 return -EINVAL; 125 126 *srm_version = hdcp_cmd->out_msg.hdcp_set_srm.srm_version; 127 return 0; 128 } 129 130 static void process_output(struct hdcp_workqueue *hdcp_work) 131 { 132 struct mod_hdcp_output output = hdcp_work->output; 133 134 if (output.callback_stop) 135 cancel_delayed_work(&hdcp_work->callback_dwork); 136 137 if (output.callback_needed) 138 schedule_delayed_work(&hdcp_work->callback_dwork, 139 msecs_to_jiffies(output.callback_delay)); 140 141 if (output.watchdog_timer_stop) 142 cancel_delayed_work(&hdcp_work->watchdog_timer_dwork); 143 144 if (output.watchdog_timer_needed) 145 schedule_delayed_work(&hdcp_work->watchdog_timer_dwork, 146 msecs_to_jiffies(output.watchdog_timer_delay)); 147 148 schedule_delayed_work(&hdcp_work->property_validate_dwork, msecs_to_jiffies(0)); 149 } 150 151 static void link_lock(struct hdcp_workqueue *work, bool lock) 152 { 153 154 int i = 0; 155 156 for (i = 0; i < work->max_link; i++) { 157 if (lock) 158 mutex_lock(&work[i].mutex); 159 else 160 mutex_unlock(&work[i].mutex); 161 } 162 } 163 void hdcp_update_display(struct hdcp_workqueue *hdcp_work, 164 unsigned int link_index, 165 struct amdgpu_dm_connector *aconnector, 166 uint8_t content_type, 167 bool enable_encryption) 168 { 169 struct hdcp_workqueue *hdcp_w = &hdcp_work[link_index]; 170 struct mod_hdcp_display *display = &hdcp_work[link_index].display; 171 struct mod_hdcp_link *link = &hdcp_work[link_index].link; 172 struct mod_hdcp_display_query query; 173 174 mutex_lock(&hdcp_w->mutex); 175 hdcp_w->aconnector = aconnector; 176 177 query.display = NULL; 178 mod_hdcp_query_display(&hdcp_w->hdcp, aconnector->base.index, &query); 179 180 if (query.display != NULL) { 181 memcpy(display, query.display, sizeof(struct mod_hdcp_display)); 182 mod_hdcp_remove_display(&hdcp_w->hdcp, aconnector->base.index, &hdcp_w->output); 183 184 hdcp_w->link.adjust.hdcp2.force_type = MOD_HDCP_FORCE_TYPE_0; 185 186 if (enable_encryption) { 187 /* Explicitly set the saved SRM as sysfs call will be after we already enabled hdcp 188 * (s3 resume case) 189 */ 190 if (hdcp_work->srm_size > 0) 191 psp_set_srm(hdcp_work->hdcp.config.psp.handle, hdcp_work->srm, hdcp_work->srm_size, 192 &hdcp_work->srm_version); 193 194 display->adjust.disable = 0; 195 if (content_type == DRM_MODE_HDCP_CONTENT_TYPE0) { 196 hdcp_w->link.adjust.hdcp1.disable = 0; 197 hdcp_w->link.adjust.hdcp2.force_type = MOD_HDCP_FORCE_TYPE_0; 198 } else if (content_type == DRM_MODE_HDCP_CONTENT_TYPE1) { 199 hdcp_w->link.adjust.hdcp1.disable = 1; 200 hdcp_w->link.adjust.hdcp2.force_type = MOD_HDCP_FORCE_TYPE_1; 201 } 202 203 schedule_delayed_work(&hdcp_w->property_validate_dwork, 204 msecs_to_jiffies(DRM_HDCP_CHECK_PERIOD_MS)); 205 } else { 206 display->adjust.disable = 1; 207 hdcp_w->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF; 208 cancel_delayed_work(&hdcp_w->property_validate_dwork); 209 } 210 211 display->state = MOD_HDCP_DISPLAY_ACTIVE; 212 } 213 214 mod_hdcp_add_display(&hdcp_w->hdcp, link, display, &hdcp_w->output); 215 216 process_output(hdcp_w); 217 mutex_unlock(&hdcp_w->mutex); 218 } 219 220 static void hdcp_remove_display(struct hdcp_workqueue *hdcp_work, 221 unsigned int link_index, 222 struct amdgpu_dm_connector *aconnector) 223 { 224 struct hdcp_workqueue *hdcp_w = &hdcp_work[link_index]; 225 226 mutex_lock(&hdcp_w->mutex); 227 hdcp_w->aconnector = aconnector; 228 229 mod_hdcp_remove_display(&hdcp_w->hdcp, aconnector->base.index, &hdcp_w->output); 230 231 process_output(hdcp_w); 232 mutex_unlock(&hdcp_w->mutex); 233 } 234 void hdcp_reset_display(struct hdcp_workqueue *hdcp_work, unsigned int link_index) 235 { 236 struct hdcp_workqueue *hdcp_w = &hdcp_work[link_index]; 237 238 mutex_lock(&hdcp_w->mutex); 239 240 mod_hdcp_reset_connection(&hdcp_w->hdcp, &hdcp_w->output); 241 242 cancel_delayed_work(&hdcp_w->property_validate_dwork); 243 hdcp_w->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF; 244 245 process_output(hdcp_w); 246 247 mutex_unlock(&hdcp_w->mutex); 248 } 249 250 void hdcp_handle_cpirq(struct hdcp_workqueue *hdcp_work, unsigned int link_index) 251 { 252 struct hdcp_workqueue *hdcp_w = &hdcp_work[link_index]; 253 254 schedule_work(&hdcp_w->cpirq_work); 255 } 256 257 258 259 260 static void event_callback(struct work_struct *work) 261 { 262 struct hdcp_workqueue *hdcp_work; 263 264 hdcp_work = container_of(to_delayed_work(work), struct hdcp_workqueue, 265 callback_dwork); 266 267 mutex_lock(&hdcp_work->mutex); 268 269 cancel_delayed_work(&hdcp_work->callback_dwork); 270 271 mod_hdcp_process_event(&hdcp_work->hdcp, MOD_HDCP_EVENT_CALLBACK, 272 &hdcp_work->output); 273 274 process_output(hdcp_work); 275 276 mutex_unlock(&hdcp_work->mutex); 277 278 279 } 280 static void event_property_update(struct work_struct *work) 281 { 282 283 struct hdcp_workqueue *hdcp_work = container_of(work, struct hdcp_workqueue, property_update_work); 284 struct amdgpu_dm_connector *aconnector = hdcp_work->aconnector; 285 struct drm_device *dev = hdcp_work->aconnector->base.dev; 286 long ret; 287 288 drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); 289 mutex_lock(&hdcp_work->mutex); 290 291 292 if (aconnector->base.state->commit) { 293 ret = wait_for_completion_interruptible_timeout(&aconnector->base.state->commit->hw_done, 10 * HZ); 294 295 if (ret == 0) { 296 DRM_ERROR("HDCP state unknown! Setting it to DESIRED"); 297 hdcp_work->encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF; 298 } 299 } 300 301 if (hdcp_work->encryption_status != MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF) { 302 if (aconnector->base.state->hdcp_content_type == DRM_MODE_HDCP_CONTENT_TYPE0 && 303 hdcp_work->encryption_status <= MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE0_ON) 304 drm_hdcp_update_content_protection(&aconnector->base, DRM_MODE_CONTENT_PROTECTION_ENABLED); 305 else if (aconnector->base.state->hdcp_content_type == DRM_MODE_HDCP_CONTENT_TYPE1 && 306 hdcp_work->encryption_status == MOD_HDCP_ENCRYPTION_STATUS_HDCP2_TYPE1_ON) 307 drm_hdcp_update_content_protection(&aconnector->base, DRM_MODE_CONTENT_PROTECTION_ENABLED); 308 } else { 309 drm_hdcp_update_content_protection(&aconnector->base, DRM_MODE_CONTENT_PROTECTION_DESIRED); 310 } 311 312 313 mutex_unlock(&hdcp_work->mutex); 314 drm_modeset_unlock(&dev->mode_config.connection_mutex); 315 } 316 317 static void event_property_validate(struct work_struct *work) 318 { 319 struct hdcp_workqueue *hdcp_work = 320 container_of(to_delayed_work(work), struct hdcp_workqueue, property_validate_dwork); 321 struct mod_hdcp_display_query query; 322 struct amdgpu_dm_connector *aconnector = hdcp_work->aconnector; 323 324 if (!aconnector) 325 return; 326 327 mutex_lock(&hdcp_work->mutex); 328 329 query.encryption_status = MOD_HDCP_ENCRYPTION_STATUS_HDCP_OFF; 330 mod_hdcp_query_display(&hdcp_work->hdcp, aconnector->base.index, &query); 331 332 if (query.encryption_status != hdcp_work->encryption_status) { 333 hdcp_work->encryption_status = query.encryption_status; 334 schedule_work(&hdcp_work->property_update_work); 335 } 336 337 mutex_unlock(&hdcp_work->mutex); 338 } 339 340 static void event_watchdog_timer(struct work_struct *work) 341 { 342 struct hdcp_workqueue *hdcp_work; 343 344 hdcp_work = container_of(to_delayed_work(work), 345 struct hdcp_workqueue, 346 watchdog_timer_dwork); 347 348 mutex_lock(&hdcp_work->mutex); 349 350 cancel_delayed_work(&hdcp_work->watchdog_timer_dwork); 351 352 mod_hdcp_process_event(&hdcp_work->hdcp, 353 MOD_HDCP_EVENT_WATCHDOG_TIMEOUT, 354 &hdcp_work->output); 355 356 process_output(hdcp_work); 357 358 mutex_unlock(&hdcp_work->mutex); 359 360 } 361 362 static void event_cpirq(struct work_struct *work) 363 { 364 struct hdcp_workqueue *hdcp_work; 365 366 hdcp_work = container_of(work, struct hdcp_workqueue, cpirq_work); 367 368 mutex_lock(&hdcp_work->mutex); 369 370 mod_hdcp_process_event(&hdcp_work->hdcp, MOD_HDCP_EVENT_CPIRQ, &hdcp_work->output); 371 372 process_output(hdcp_work); 373 374 mutex_unlock(&hdcp_work->mutex); 375 376 } 377 378 379 void hdcp_destroy(struct kobject *kobj, struct hdcp_workqueue *hdcp_work) 380 { 381 int i = 0; 382 383 for (i = 0; i < hdcp_work->max_link; i++) { 384 cancel_delayed_work_sync(&hdcp_work[i].callback_dwork); 385 cancel_delayed_work_sync(&hdcp_work[i].watchdog_timer_dwork); 386 } 387 388 sysfs_remove_bin_file(kobj, &hdcp_work[0].attr); 389 kfree(hdcp_work->srm); 390 kfree(hdcp_work->srm_temp); 391 kfree(hdcp_work); 392 } 393 394 395 static bool enable_assr(void *handle, struct dc_link *link) 396 { 397 398 struct hdcp_workqueue *hdcp_work = handle; 399 struct mod_hdcp hdcp = hdcp_work->hdcp; 400 struct psp_context *psp = hdcp.config.psp.handle; 401 struct ta_dtm_shared_memory *dtm_cmd; 402 bool res = true; 403 404 if (!psp->dtm_context.dtm_initialized) { 405 DRM_INFO("Failed to enable ASSR, DTM TA is not initialized."); 406 return false; 407 } 408 409 dtm_cmd = (struct ta_dtm_shared_memory *)psp->dtm_context.dtm_shared_buf; 410 411 mutex_lock(&psp->dtm_context.mutex); 412 memset(dtm_cmd, 0, sizeof(struct ta_dtm_shared_memory)); 413 414 dtm_cmd->cmd_id = TA_DTM_COMMAND__TOPOLOGY_ASSR_ENABLE; 415 dtm_cmd->dtm_in_message.topology_assr_enable.display_topology_dig_be_index = link->link_enc_hw_inst; 416 dtm_cmd->dtm_status = TA_DTM_STATUS__GENERIC_FAILURE; 417 418 psp_dtm_invoke(psp, dtm_cmd->cmd_id); 419 420 if (dtm_cmd->dtm_status != TA_DTM_STATUS__SUCCESS) { 421 DRM_INFO("Failed to enable ASSR"); 422 res = false; 423 } 424 425 mutex_unlock(&psp->dtm_context.mutex); 426 427 return res; 428 } 429 430 static void update_config(void *handle, struct cp_psp_stream_config *config) 431 { 432 struct hdcp_workqueue *hdcp_work = handle; 433 struct amdgpu_dm_connector *aconnector = config->dm_stream_ctx; 434 int link_index = aconnector->dc_link->link_index; 435 struct mod_hdcp_display *display = &hdcp_work[link_index].display; 436 struct mod_hdcp_link *link = &hdcp_work[link_index].link; 437 438 if (config->dpms_off) { 439 hdcp_remove_display(hdcp_work, link_index, aconnector); 440 return; 441 } 442 443 memset(display, 0, sizeof(*display)); 444 memset(link, 0, sizeof(*link)); 445 446 display->index = aconnector->base.index; 447 display->state = MOD_HDCP_DISPLAY_ACTIVE; 448 449 if (aconnector->dc_sink != NULL) 450 link->mode = mod_hdcp_signal_type_to_operation_mode(aconnector->dc_sink->sink_signal); 451 452 display->controller = CONTROLLER_ID_D0 + config->otg_inst; 453 display->dig_fe = config->dig_fe; 454 link->dig_be = config->dig_be; 455 link->ddc_line = aconnector->dc_link->ddc_hw_inst + 1; 456 link->dp.rev = aconnector->dc_link->dpcd_caps.dpcd_rev.raw; 457 link->dp.assr_enabled = config->assr_enabled; 458 link->dp.mst_enabled = config->mst_enabled; 459 display->adjust.disable = 1; 460 link->adjust.auth_delay = 3; 461 link->adjust.hdcp1.disable = 0; 462 463 hdcp_update_display(hdcp_work, link_index, aconnector, DRM_MODE_HDCP_CONTENT_TYPE0, false); 464 } 465 466 467 /* NOTE: From the usermodes prospective you only need to call write *ONCE*, the kernel 468 * will automatically call once or twice depending on the size 469 * 470 * call: "cat file > /sys/class/drm/card0/device/hdcp_srm" from usermode no matter what the size is 471 * 472 * The kernel can only send PAGE_SIZE at once and since MAX_SRM_FILE(5120) > PAGE_SIZE(4096), 473 * srm_data_write can be called multiple times. 474 * 475 * sysfs interface doesn't tell us the size we will get so we are sending partial SRMs to psp and on 476 * the last call we will send the full SRM. PSP will fail on every call before the last. 477 * 478 * This means we don't know if the SRM is good until the last call. And because of this limitation we 479 * cannot throw errors early as it will stop the kernel from writing to sysfs 480 * 481 * Example 1: 482 * Good SRM size = 5096 483 * first call to write 4096 -> PSP fails 484 * Second call to write 1000 -> PSP Pass -> SRM is set 485 * 486 * Example 2: 487 * Bad SRM size = 4096 488 * first call to write 4096 -> PSP fails (This is the same as above, but we don't know if this 489 * is the last call) 490 * 491 * Solution?: 492 * 1: Parse the SRM? -> It is signed so we don't know the EOF 493 * 2: We can have another sysfs that passes the size before calling set. -> simpler solution 494 * below 495 * 496 * Easy Solution: 497 * Always call get after Set to verify if set was successful. 498 * +----------------------+ 499 * | Why it works: | 500 * +----------------------+ 501 * PSP will only update its srm if its older than the one we are trying to load. 502 * Always do set first than get. 503 * -if we try to "1. SET" a older version PSP will reject it and we can "2. GET" the newer 504 * version and save it 505 * 506 * -if we try to "1. SET" a newer version PSP will accept it and we can "2. GET" the 507 * same(newer) version back and save it 508 * 509 * -if we try to "1. SET" a newer version and PSP rejects it. That means the format is 510 * incorrect/corrupted and we should correct our SRM by getting it from PSP 511 */ 512 static ssize_t srm_data_write(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buffer, 513 loff_t pos, size_t count) 514 { 515 struct hdcp_workqueue *work; 516 uint32_t srm_version = 0; 517 518 work = container_of(bin_attr, struct hdcp_workqueue, attr); 519 link_lock(work, true); 520 521 memcpy(work->srm_temp + pos, buffer, count); 522 523 if (!psp_set_srm(work->hdcp.config.psp.handle, work->srm_temp, pos + count, &srm_version)) { 524 DRM_DEBUG_DRIVER("HDCP SRM SET version 0x%X", srm_version); 525 memcpy(work->srm, work->srm_temp, pos + count); 526 work->srm_size = pos + count; 527 work->srm_version = srm_version; 528 } 529 530 531 link_lock(work, false); 532 533 return count; 534 } 535 536 static ssize_t srm_data_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buffer, 537 loff_t pos, size_t count) 538 { 539 struct hdcp_workqueue *work; 540 uint8_t *srm = NULL; 541 uint32_t srm_version; 542 uint32_t srm_size; 543 size_t ret = count; 544 545 work = container_of(bin_attr, struct hdcp_workqueue, attr); 546 547 link_lock(work, true); 548 549 srm = psp_get_srm(work->hdcp.config.psp.handle, &srm_version, &srm_size); 550 551 if (!srm) { 552 ret = -EINVAL; 553 goto ret; 554 } 555 556 if (pos >= srm_size) 557 ret = 0; 558 559 if (srm_size - pos < count) { 560 memcpy(buffer, srm + pos, srm_size - pos); 561 ret = srm_size - pos; 562 goto ret; 563 } 564 565 memcpy(buffer, srm + pos, count); 566 567 ret: 568 link_lock(work, false); 569 return ret; 570 } 571 572 /* From the hdcp spec (5.Renewability) SRM needs to be stored in a non-volatile memory. 573 * 574 * For example, 575 * if Application "A" sets the SRM (ver 2) and we reboot/suspend and later when Application "B" 576 * needs to use HDCP, the version in PSP should be SRM(ver 2). So SRM should be persistent 577 * across boot/reboots/suspend/resume/shutdown 578 * 579 * Currently when the system goes down (suspend/shutdown) the SRM is cleared from PSP. For HDCP we need 580 * to make the SRM persistent. 581 * 582 * -PSP owns the checking of SRM but doesn't have the ability to store it in a non-volatile memory. 583 * -The kernel cannot write to the file systems. 584 * -So we need usermode to do this for us, which is why an interface for usermode is needed 585 * 586 * 587 * 588 * Usermode can read/write to/from PSP using the sysfs interface 589 * For example: 590 * to save SRM from PSP to storage : cat /sys/class/drm/card0/device/hdcp_srm > srmfile 591 * to load from storage to PSP: cat srmfile > /sys/class/drm/card0/device/hdcp_srm 592 */ 593 static const struct bin_attribute data_attr = { 594 .attr = {.name = "hdcp_srm", .mode = 0664}, 595 .size = PSP_HDCP_SRM_FIRST_GEN_MAX_SIZE, /* Limit SRM size */ 596 .write = srm_data_write, 597 .read = srm_data_read, 598 }; 599 600 601 struct hdcp_workqueue *hdcp_create_workqueue(struct amdgpu_device *adev, struct cp_psp *cp_psp, struct dc *dc) 602 { 603 604 int max_caps = dc->caps.max_links; 605 struct hdcp_workqueue *hdcp_work; 606 int i = 0; 607 608 hdcp_work = kcalloc(max_caps, sizeof(*hdcp_work), GFP_KERNEL); 609 if (ZERO_OR_NULL_PTR(hdcp_work)) 610 return NULL; 611 612 hdcp_work->srm = kcalloc(PSP_HDCP_SRM_FIRST_GEN_MAX_SIZE, sizeof(*hdcp_work->srm), GFP_KERNEL); 613 614 if (hdcp_work->srm == NULL) 615 goto fail_alloc_context; 616 617 hdcp_work->srm_temp = kcalloc(PSP_HDCP_SRM_FIRST_GEN_MAX_SIZE, sizeof(*hdcp_work->srm_temp), GFP_KERNEL); 618 619 if (hdcp_work->srm_temp == NULL) 620 goto fail_alloc_context; 621 622 hdcp_work->max_link = max_caps; 623 624 for (i = 0; i < max_caps; i++) { 625 mutex_init(&hdcp_work[i].mutex); 626 627 INIT_WORK(&hdcp_work[i].cpirq_work, event_cpirq); 628 INIT_WORK(&hdcp_work[i].property_update_work, event_property_update); 629 INIT_DELAYED_WORK(&hdcp_work[i].callback_dwork, event_callback); 630 INIT_DELAYED_WORK(&hdcp_work[i].watchdog_timer_dwork, event_watchdog_timer); 631 INIT_DELAYED_WORK(&hdcp_work[i].property_validate_dwork, event_property_validate); 632 633 hdcp_work[i].hdcp.config.psp.handle = &adev->psp; 634 hdcp_work[i].hdcp.config.ddc.handle = dc_get_link_at_index(dc, i); 635 hdcp_work[i].hdcp.config.ddc.funcs.write_i2c = lp_write_i2c; 636 hdcp_work[i].hdcp.config.ddc.funcs.read_i2c = lp_read_i2c; 637 hdcp_work[i].hdcp.config.ddc.funcs.write_dpcd = lp_write_dpcd; 638 hdcp_work[i].hdcp.config.ddc.funcs.read_dpcd = lp_read_dpcd; 639 } 640 641 cp_psp->funcs.update_stream_config = update_config; 642 cp_psp->funcs.enable_assr = enable_assr; 643 cp_psp->handle = hdcp_work; 644 645 /* File created at /sys/class/drm/card0/device/hdcp_srm*/ 646 hdcp_work[0].attr = data_attr; 647 648 if (sysfs_create_bin_file(&adev->dev->kobj, &hdcp_work[0].attr)) 649 DRM_WARN("Failed to create device file hdcp_srm"); 650 651 return hdcp_work; 652 653 fail_alloc_context: 654 kfree(hdcp_work->srm); 655 kfree(hdcp_work->srm_temp); 656 kfree(hdcp_work); 657 658 return NULL; 659 660 661 662 } 663 664 665 666