Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 | /* SPDX-License-Identifier: MIT */ /****************************************************************************** * displif.h * * Unified display device I/O interface for Xen guest OSes. * * Copyright (C) 2016-2017 EPAM Systems Inc. * * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> * Oleksandr Grytsov <oleksandr_grytsov@epam.com> */ #ifndef __XEN_PUBLIC_IO_DISPLIF_H__ #define __XEN_PUBLIC_IO_DISPLIF_H__ #include "ring.h" #include "../grant_table.h" /* ****************************************************************************** * Protocol version ****************************************************************************** */ #define XENDISPL_PROTOCOL_VERSION "2" #define XENDISPL_PROTOCOL_VERSION_INT 2 /* ****************************************************************************** * Main features provided by the protocol ****************************************************************************** * This protocol aims to provide a unified protocol which fits more * sophisticated use-cases than a framebuffer device can handle. At the * moment basic functionality is supported with the intention to be extended: * o multiple dynamically allocated/destroyed framebuffers * o buffers of arbitrary sizes * o buffer allocation at either back or front end * o better configuration options including multiple display support * * Note: existing fbif can be used together with displif running at the * same time, e.g. on Linux one provides framebuffer and another DRM/KMS * * Note: display resolution (XenStore's "resolution" property) defines * visible area of the virtual display. At the same time resolution of * the display and frame buffers may differ: buffers can be smaller, equal * or bigger than the visible area. This is to enable use-cases, where backend * may do some post-processing of the display and frame buffers supplied, * e.g. those buffers can be just a part of the final composition. * ****************************************************************************** * Direction of improvements ****************************************************************************** * Future extensions to the existing protocol may include: * o display/connector cloning * o allocation of objects other than display buffers * o plane/overlay support * o scaling support * o rotation support * ****************************************************************************** * Feature and Parameter Negotiation ****************************************************************************** * * Front->back notifications: when enqueuing a new request, sending a * notification can be made conditional on xendispl_req (i.e., the generic * hold-off mechanism provided by the ring macros). Backends must set * xendispl_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()). * * Back->front notifications: when enqueuing a new response, sending a * notification can be made conditional on xendispl_resp (i.e., the generic * hold-off mechanism provided by the ring macros). Frontends must set * xendispl_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()). * * The two halves of a para-virtual display driver utilize nodes within * XenStore to communicate capabilities and to negotiate operating parameters. * This section enumerates these nodes which reside in the respective front and * backend portions of XenStore, following the XenBus convention. * * All data in XenStore is stored as strings. Nodes specifying numeric * values are encoded in decimal. Integer value ranges listed below are * expressed as fixed sized integer types capable of storing the conversion * of a properly formated node string, without loss of information. * ****************************************************************************** * Example configuration ****************************************************************************** * * Note: depending on the use-case backend can expose more display connectors * than the underlying HW physically has by employing SW graphics compositors * * This is an example of backend and frontend configuration: * *--------------------------------- Backend ----------------------------------- * * /local/domain/0/backend/vdispl/1/0/frontend-id = "1" * /local/domain/0/backend/vdispl/1/0/frontend = "/local/domain/1/device/vdispl/0" * /local/domain/0/backend/vdispl/1/0/state = "4" * /local/domain/0/backend/vdispl/1/0/versions = "1,2" * *--------------------------------- Frontend ---------------------------------- * * /local/domain/1/device/vdispl/0/backend-id = "0" * /local/domain/1/device/vdispl/0/backend = "/local/domain/0/backend/vdispl/1/0" * /local/domain/1/device/vdispl/0/state = "4" * /local/domain/1/device/vdispl/0/version = "1" * /local/domain/1/device/vdispl/0/be-alloc = "1" * *-------------------------- Connector 0 configuration ------------------------ * * /local/domain/1/device/vdispl/0/0/resolution = "1920x1080" * /local/domain/1/device/vdispl/0/0/req-ring-ref = "2832" * /local/domain/1/device/vdispl/0/0/req-event-channel = "15" * /local/domain/1/device/vdispl/0/0/evt-ring-ref = "387" * /local/domain/1/device/vdispl/0/0/evt-event-channel = "16" * *-------------------------- Connector 1 configuration ------------------------ * * /local/domain/1/device/vdispl/0/1/resolution = "800x600" * /local/domain/1/device/vdispl/0/1/req-ring-ref = "2833" * /local/domain/1/device/vdispl/0/1/req-event-channel = "17" * /local/domain/1/device/vdispl/0/1/evt-ring-ref = "388" * /local/domain/1/device/vdispl/0/1/evt-event-channel = "18" * ****************************************************************************** * Backend XenBus Nodes ****************************************************************************** * *----------------------------- Protocol version ------------------------------ * * versions * Values: <string> * * List of XENDISPL_LIST_SEPARATOR separated protocol versions supported * by the backend. For example "1,2,3". * ****************************************************************************** * Frontend XenBus Nodes ****************************************************************************** * *-------------------------------- Addressing --------------------------------- * * dom-id * Values: <uint16_t> * * Domain identifier. * * dev-id * Values: <uint16_t> * * Device identifier. * * conn-idx * Values: <uint8_t> * * Zero based contigous index of the connector. * /local/domain/<dom-id>/device/vdispl/<dev-id>/<conn-idx>/... * *----------------------------- Protocol version ------------------------------ * * version * Values: <string> * * Protocol version, chosen among the ones supported by the backend. * *------------------------- Backend buffer allocation ------------------------- * * be-alloc * Values: "0", "1" * * If value is set to "1", then backend can be a buffer provider/allocator * for this domain during XENDISPL_OP_DBUF_CREATE operation (see below * for negotiation). * If value is not "1" or omitted frontend must allocate buffers itself. * *----------------------------- Connector settings ---------------------------- * * unique-id * Values: <string> * * After device instance initialization each connector is assigned a * unique ID, so it can be identified by the backend by this ID. * This can be UUID or such. * * resolution * Values: <width, uint32_t>x<height, uint32_t> * * Width and height of the connector in pixels separated by * XENDISPL_RESOLUTION_SEPARATOR. This defines visible area of the * display. * If backend provides extended display identification data (EDID) with * XENDISPL_OP_GET_EDID request then EDID values must take precedence * over the resolutions defined here. * *------------------ Connector Request Transport Parameters ------------------- * * This communication path is used to deliver requests from frontend to backend * and get the corresponding responses from backend to frontend, * set up per connector. * * req-event-channel * Values: <uint32_t> * * The identifier of the Xen connector's control event channel * used to signal activity in the ring buffer. * * req-ring-ref * Values: <uint32_t> * * The Xen grant reference granting permission for the backend to map * a sole page of connector's control ring buffer. * *------------------- Connector Event Transport Parameters -------------------- * * This communication path is used to deliver asynchronous events from backend * to frontend, set up per connector. * * evt-event-channel * Values: <uint32_t> * * The identifier of the Xen connector's event channel * used to signal activity in the ring buffer. * * evt-ring-ref * Values: <uint32_t> * * The Xen grant reference granting permission for the backend to map * a sole page of connector's event ring buffer. */ /* ****************************************************************************** * STATE DIAGRAMS ****************************************************************************** * * Tool stack creates front and back state nodes with initial state * XenbusStateInitialising. * Tool stack creates and sets up frontend display configuration * nodes per domain. * *-------------------------------- Normal flow -------------------------------- * * Front Back * ================================= ===================================== * XenbusStateInitialising XenbusStateInitialising * o Query backend device identification * data. * o Open and validate backend device. * | * | * V * XenbusStateInitWait * * o Query frontend configuration * o Allocate and initialize * event channels per configured * connector. * o Publish transport parameters * that will be in effect during * this connection. * | * | * V * XenbusStateInitialised * * o Query frontend transport parameters. * o Connect to the event channels. * | * | * V * XenbusStateConnected * * o Create and initialize OS * virtual display connectors * as per configuration. * | * | * V * XenbusStateConnected * * XenbusStateUnknown * XenbusStateClosed * XenbusStateClosing * o Remove virtual display device * o Remove event channels * | * | * V * XenbusStateClosed * *------------------------------- Recovery flow ------------------------------- * * In case of frontend unrecoverable errors backend handles that as * if frontend goes into the XenbusStateClosed state. * * In case of backend unrecoverable errors frontend tries removing * the virtualized device. If this is possible at the moment of error, * then frontend goes into the XenbusStateInitialising state and is ready for * new connection with backend. If the virtualized device is still in use and * cannot be removed, then frontend goes into the XenbusStateReconfiguring state * until either the virtualized device is removed or backend initiates a new * connection. On the virtualized device removal frontend goes into the * XenbusStateInitialising state. * * Note on XenbusStateReconfiguring state of the frontend: if backend has * unrecoverable errors then frontend cannot send requests to the backend * and thus cannot provide functionality of the virtualized device anymore. * After backend is back to normal the virtualized device may still hold some * state: configuration in use, allocated buffers, client application state etc. * In most cases, this will require frontend to implement complex recovery * reconnect logic. Instead, by going into XenbusStateReconfiguring state, * frontend will make sure no new clients of the virtualized device are * accepted, allow existing client(s) to exit gracefully by signaling error * state etc. * Once all the clients are gone frontend can reinitialize the virtualized * device and get into XenbusStateInitialising state again signaling the * backend that a new connection can be made. * * There are multiple conditions possible under which frontend will go from * XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS * specific. For example: * 1. The underlying OS framework may provide callbacks to signal that the last * client of the virtualized device has gone and the device can be removed * 2. Frontend can schedule a deferred work (timer/tasklet/workqueue) * to periodically check if this is the right time to re-try removal of * the virtualized device. * 3. By any other means. * ****************************************************************************** * REQUEST CODES ****************************************************************************** * Request codes [0; 15] are reserved and must not be used */ #define XENDISPL_OP_DBUF_CREATE 0x10 #define XENDISPL_OP_DBUF_DESTROY 0x11 #define XENDISPL_OP_FB_ATTACH 0x12 #define XENDISPL_OP_FB_DETACH 0x13 #define XENDISPL_OP_SET_CONFIG 0x14 #define XENDISPL_OP_PG_FLIP 0x15 /* The below command is available in protocol version 2 and above. */ #define XENDISPL_OP_GET_EDID 0x16 /* ****************************************************************************** * EVENT CODES ****************************************************************************** */ #define XENDISPL_EVT_PG_FLIP 0x00 /* ****************************************************************************** * XENSTORE FIELD AND PATH NAME STRINGS, HELPERS ****************************************************************************** */ #define XENDISPL_DRIVER_NAME "vdispl" #define XENDISPL_LIST_SEPARATOR "," #define XENDISPL_RESOLUTION_SEPARATOR "x" #define XENDISPL_FIELD_BE_VERSIONS "versions" #define XENDISPL_FIELD_FE_VERSION "version" #define XENDISPL_FIELD_REQ_RING_REF "req-ring-ref" #define XENDISPL_FIELD_REQ_CHANNEL "req-event-channel" #define XENDISPL_FIELD_EVT_RING_REF "evt-ring-ref" #define XENDISPL_FIELD_EVT_CHANNEL "evt-event-channel" #define XENDISPL_FIELD_RESOLUTION "resolution" #define XENDISPL_FIELD_BE_ALLOC "be-alloc" #define XENDISPL_FIELD_UNIQUE_ID "unique-id" #define XENDISPL_EDID_BLOCK_SIZE 128 #define XENDISPL_EDID_BLOCK_COUNT 256 #define XENDISPL_EDID_MAX_SIZE (XENDISPL_EDID_BLOCK_SIZE * XENDISPL_EDID_BLOCK_COUNT) /* ****************************************************************************** * STATUS RETURN CODES ****************************************************************************** * * Status return code is zero on success and -XEN_EXX on failure. * ****************************************************************************** * Assumptions ****************************************************************************** * o usage of grant reference 0 as invalid grant reference: * grant reference 0 is valid, but never exposed to a PV driver, * because of the fact it is already in use/reserved by the PV console. * o all references in this document to page sizes must be treated * as pages of size XEN_PAGE_SIZE unless otherwise noted. * ****************************************************************************** * Description of the protocol between frontend and backend driver ****************************************************************************** * * The two halves of a Para-virtual display driver communicate with * each other using shared pages and event channels. * Shared page contains a ring with request/response packets. * * All reserved fields in the structures below must be 0. * Display buffers's cookie of value 0 is treated as invalid. * Framebuffer's cookie of value 0 is treated as invalid. * * For all request/response/event packets that use cookies: * dbuf_cookie - uint64_t, unique to guest domain value used by the backend * to map remote display buffer to its local one * fb_cookie - uint64_t, unique to guest domain value used by the backend * to map remote framebuffer to its local one * *---------------------------------- Requests --------------------------------- * * All requests/responses, which are not connector specific, must be sent over * control ring of the connector which has the index value of 0: * /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref * * All request packets have the same length (64 octets) * All request packets have common header: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | operation | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * id - uint16_t, private guest value, echoed in response * operation - uint8_t, operation code, XENDISPL_OP_??? * * Request dbuf creation - request creation of a display buffer. * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id |_OP_DBUF_CREATE | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * | dbuf_cookie low 32-bit | 12 * +----------------+----------------+----------------+----------------+ * | dbuf_cookie high 32-bit | 16 * +----------------+----------------+----------------+----------------+ * | width | 20 * +----------------+----------------+----------------+----------------+ * | height | 24 * +----------------+----------------+----------------+----------------+ * | bpp | 28 * +----------------+----------------+----------------+----------------+ * | buffer_sz | 32 * +----------------+----------------+----------------+----------------+ * | flags | 36 * +----------------+----------------+----------------+----------------+ * | gref_directory | 40 * +----------------+----------------+----------------+----------------+ * | data_ofs | 44 * +----------------+----------------+----------------+----------------+ * | reserved | 48 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * Must be sent over control ring of the connector which has the index * value of 0: * /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref * All unused bits in flags field must be set to 0. * * An attempt to create multiple display buffers with the same dbuf_cookie is * an error. dbuf_cookie can be re-used after destroying the corresponding * display buffer. * * Width and height of the display buffers can be smaller, equal or bigger * than the connector's resolution. Depth/pixel format of the individual * buffers can differ as well. * * width - uint32_t, width in pixels * height - uint32_t, height in pixels * bpp - uint32_t, bits per pixel * buffer_sz - uint32_t, buffer size to be allocated, octets * flags - uint32_t, flags of the operation * o XENDISPL_DBUF_FLG_REQ_ALLOC - if set, then backend is requested * to allocate the buffer with the parameters provided in this request. * Page directory is handled as follows: * Frontend on request: * o allocates pages for the directory (gref_directory, * gref_dir_next_page(s) * o grants permissions for the pages of the directory to the backend * o sets gref_dir_next_page fields * Backend on response: * o grants permissions for the pages of the buffer allocated to * the frontend * o fills in page directory with grant references * (gref[] in struct xendispl_page_directory) * gref_directory - grant_ref_t, a reference to the first shared page * describing shared buffer references. At least one page exists. If shared * buffer size (buffer_sz) exceeds what can be addressed by this single page, * then reference to the next page must be supplied (see gref_dir_next_page * below) * data_ofs - uint32_t, offset of the data in the buffer, octets */ #define XENDISPL_DBUF_FLG_REQ_ALLOC (1 << 0) struct xendispl_dbuf_create_req { uint64_t dbuf_cookie; uint32_t width; uint32_t height; uint32_t bpp; uint32_t buffer_sz; uint32_t flags; grant_ref_t gref_directory; uint32_t data_ofs; }; /* * Shared page for XENDISPL_OP_DBUF_CREATE buffer descriptor (gref_directory in * the request) employs a list of pages, describing all pages of the shared * data buffer: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | gref_dir_next_page | 4 * +----------------+----------------+----------------+----------------+ * | gref[0] | 8 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | gref[i] | i*4+8 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | gref[N - 1] | N*4+8 * +----------------+----------------+----------------+----------------+ * * gref_dir_next_page - grant_ref_t, reference to the next page describing * page directory. Must be 0 if there are no more pages in the list. * gref[i] - grant_ref_t, reference to a shared page of the buffer * allocated at XENDISPL_OP_DBUF_CREATE * * Number of grant_ref_t entries in the whole page directory is not * passed, but instead can be calculated as: * num_grefs_total = (XENDISPL_OP_DBUF_CREATE.buffer_sz + XEN_PAGE_SIZE - 1) / * XEN_PAGE_SIZE */ struct xendispl_page_directory { grant_ref_t gref_dir_next_page; grant_ref_t gref[1]; /* Variable length */ }; /* * Request dbuf destruction - destroy a previously allocated display buffer: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id |_OP_DBUF_DESTROY| reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * | dbuf_cookie low 32-bit | 12 * +----------------+----------------+----------------+----------------+ * | dbuf_cookie high 32-bit | 16 * +----------------+----------------+----------------+----------------+ * | reserved | 20 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * Must be sent over control ring of the connector which has the index * value of 0: * /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref */ struct xendispl_dbuf_destroy_req { uint64_t dbuf_cookie; }; /* * Request framebuffer attachment - request attachment of a framebuffer to * previously created display buffer. * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | _OP_FB_ATTACH | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * | dbuf_cookie low 32-bit | 12 * +----------------+----------------+----------------+----------------+ * | dbuf_cookie high 32-bit | 16 * +----------------+----------------+----------------+----------------+ * | fb_cookie low 32-bit | 20 * +----------------+----------------+----------------+----------------+ * | fb_cookie high 32-bit | 24 * +----------------+----------------+----------------+----------------+ * | width | 28 * +----------------+----------------+----------------+----------------+ * | height | 32 * +----------------+----------------+----------------+----------------+ * | pixel_format | 36 * +----------------+----------------+----------------+----------------+ * | reserved | 40 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * Must be sent over control ring of the connector which has the index * value of 0: * /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref * Width and height can be smaller, equal or bigger than the connector's * resolution. * * An attempt to create multiple frame buffers with the same fb_cookie is * an error. fb_cookie can be re-used after destroying the corresponding * frame buffer. * * width - uint32_t, width in pixels * height - uint32_t, height in pixels * pixel_format - uint32_t, pixel format of the framebuffer, FOURCC code */ struct xendispl_fb_attach_req { uint64_t dbuf_cookie; uint64_t fb_cookie; uint32_t width; uint32_t height; uint32_t pixel_format; }; /* * Request framebuffer detach - detach a previously * attached framebuffer from the display buffer in request: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | _OP_FB_DETACH | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * | fb_cookie low 32-bit | 12 * +----------------+----------------+----------------+----------------+ * | fb_cookie high 32-bit | 16 * +----------------+----------------+----------------+----------------+ * | reserved | 20 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * Must be sent over control ring of the connector which has the index * value of 0: * /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref */ struct xendispl_fb_detach_req { uint64_t fb_cookie; }; /* * Request configuration set/reset - request to set or reset * the configuration/mode of the display: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | _OP_SET_CONFIG | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * | fb_cookie low 32-bit | 12 * +----------------+----------------+----------------+----------------+ * | fb_cookie high 32-bit | 16 * +----------------+----------------+----------------+----------------+ * | x | 20 * +----------------+----------------+----------------+----------------+ * | y | 24 * +----------------+----------------+----------------+----------------+ * | width | 28 * +----------------+----------------+----------------+----------------+ * | height | 32 * +----------------+----------------+----------------+----------------+ * | bpp | 40 * +----------------+----------------+----------------+----------------+ * | reserved | 44 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * Pass all zeros to reset, otherwise command is treated as * configuration set. * Framebuffer's cookie defines which framebuffer/dbuf must be * displayed while enabling display (applying configuration). * x, y, width and height are bound by the connector's resolution and must not * exceed it. * * x - uint32_t, starting position in pixels by X axis * y - uint32_t, starting position in pixels by Y axis * width - uint32_t, width in pixels * height - uint32_t, height in pixels * bpp - uint32_t, bits per pixel */ struct xendispl_set_config_req { uint64_t fb_cookie; uint32_t x; uint32_t y; uint32_t width; uint32_t height; uint32_t bpp; }; /* * Request page flip - request to flip a page identified by the framebuffer * cookie: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | _OP_PG_FLIP | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * | fb_cookie low 32-bit | 12 * +----------------+----------------+----------------+----------------+ * | fb_cookie high 32-bit | 16 * +----------------+----------------+----------------+----------------+ * | reserved | 20 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ */ struct xendispl_page_flip_req { uint64_t fb_cookie; }; /* * Request EDID - request EDID describing current connector: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | _OP_GET_EDID | reserved | 4 * +----------------+----------------+----------------+----------------+ * | buffer_sz | 8 * +----------------+----------------+----------------+----------------+ * | gref_directory | 12 * +----------------+----------------+----------------+----------------+ * | reserved | 16 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * Notes: * - This command is not available in protocol version 1 and should be * ignored. * - This request is optional and if not supported then visible area * is defined by the relevant XenStore's "resolution" property. * - Shared buffer, allocated for EDID storage, must not be less then * XENDISPL_EDID_MAX_SIZE octets. * * buffer_sz - uint32_t, buffer size to be allocated, octets * gref_directory - grant_ref_t, a reference to the first shared page * describing EDID buffer references. See XENDISPL_OP_DBUF_CREATE for * grant page directory structure (struct xendispl_page_directory). * * See response format for this request. */ struct xendispl_get_edid_req { uint32_t buffer_sz; grant_ref_t gref_directory; }; /* *---------------------------------- Responses -------------------------------- * * All response packets have the same length (64 octets) * * All response packets have common header: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | reserved | 4 * +----------------+----------------+----------------+----------------+ * | status | 8 * +----------------+----------------+----------------+----------------+ * | reserved | 12 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * id - uint16_t, private guest value, echoed from request * status - int32_t, response status, zero on success and -XEN_EXX on failure * * * Get EDID response - response for XENDISPL_OP_GET_EDID: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | operation | reserved | 4 * +----------------+----------------+----------------+----------------+ * | status | 8 * +----------------+----------------+----------------+----------------+ * | edid_sz | 12 * +----------------+----------------+----------------+----------------+ * | reserved | 16 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ * * Notes: * - This response is not available in protocol version 1 and should be * ignored. * * edid_sz - uint32_t, size of the EDID, octets */ struct xendispl_get_edid_resp { uint32_t edid_sz; }; /* *----------------------------------- Events ---------------------------------- * * Events are sent via a shared page allocated by the front and propagated by * evt-event-channel/evt-ring-ref XenStore entries * All event packets have the same length (64 octets) * All event packets have common header: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | type | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * * id - uint16_t, event id, may be used by front * type - uint8_t, type of the event * * * Page flip complete event - event from back to front on page flip completed: * 0 1 2 3 octet * +----------------+----------------+----------------+----------------+ * | id | _EVT_PG_FLIP | reserved | 4 * +----------------+----------------+----------------+----------------+ * | reserved | 8 * +----------------+----------------+----------------+----------------+ * | fb_cookie low 32-bit | 12 * +----------------+----------------+----------------+----------------+ * | fb_cookie high 32-bit | 16 * +----------------+----------------+----------------+----------------+ * | reserved | 20 * +----------------+----------------+----------------+----------------+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| * +----------------+----------------+----------------+----------------+ * | reserved | 64 * +----------------+----------------+----------------+----------------+ */ struct xendispl_pg_flip_evt { uint64_t fb_cookie; }; struct xendispl_req { uint16_t id; uint8_t operation; uint8_t reserved[5]; union { struct xendispl_dbuf_create_req dbuf_create; struct xendispl_dbuf_destroy_req dbuf_destroy; struct xendispl_fb_attach_req fb_attach; struct xendispl_fb_detach_req fb_detach; struct xendispl_set_config_req set_config; struct xendispl_page_flip_req pg_flip; struct xendispl_get_edid_req get_edid; uint8_t reserved[56]; } op; }; struct xendispl_resp { uint16_t id; uint8_t operation; uint8_t reserved; int32_t status; union { struct xendispl_get_edid_resp get_edid; uint8_t reserved1[56]; } op; }; struct xendispl_evt { uint16_t id; uint8_t type; uint8_t reserved[5]; union { struct xendispl_pg_flip_evt pg_flip; uint8_t reserved[56]; } op; }; DEFINE_RING_TYPES(xen_displif, struct xendispl_req, struct xendispl_resp); /* ****************************************************************************** * Back to front events delivery ****************************************************************************** * In order to deliver asynchronous events from back to front a shared page is * allocated by front and its granted reference propagated to back via * XenStore entries (evt-ring-ref/evt-event-channel). * This page has a common header used by both front and back to synchronize * access and control event's ring buffer, while back being a producer of the * events and front being a consumer. The rest of the page after the header * is used for event packets. * * Upon reception of an event(s) front may confirm its reception * for either each event, group of events or none. */ struct xendispl_event_page { uint32_t in_cons; uint32_t in_prod; uint8_t reserved[56]; }; #define XENDISPL_EVENT_PAGE_SIZE XEN_PAGE_SIZE #define XENDISPL_IN_RING_OFFS (sizeof(struct xendispl_event_page)) #define XENDISPL_IN_RING_SIZE (XENDISPL_EVENT_PAGE_SIZE - XENDISPL_IN_RING_OFFS) #define XENDISPL_IN_RING_LEN (XENDISPL_IN_RING_SIZE / sizeof(struct xendispl_evt)) #define XENDISPL_IN_RING(page) \ ((struct xendispl_evt *)((char *)(page) + XENDISPL_IN_RING_OFFS)) #define XENDISPL_IN_RING_REF(page, idx) \ (XENDISPL_IN_RING((page))[(idx) % XENDISPL_IN_RING_LEN]) #endif /* __XEN_PUBLIC_IO_DISPLIF_H__ */ |