| /****************************************************************************** | |
| * displif.h | |
| * | |
| * Unified display device I/O interface for Xen guest OSes. | |
| * | |
| * Permission is hereby granted, free of charge, to any person obtaining a copy | |
| * of this software and associated documentation files (the "Software"), to | |
| * deal in the Software without restriction, including without limitation the | |
| * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or | |
| * sell copies of the Software, and to permit persons to whom the Software is | |
| * furnished to do so, subject to the following conditions: | |
| * | |
| * The above copyright notice and this permission notice shall be included in | |
| * all copies or substantial portions of the Software. | |
| * | |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER | |
| * DEALINGS IN THE SOFTWARE. | |
| * | |
| * 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 "1" | |
| /* | |
| ****************************************************************************** | |
| * 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 ---------------------------- | |
| * | |
| * 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. | |
| * | |
| *------------------ 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 | |
| /* | |
| ****************************************************************************** | |
| * 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" | |
| /* | |
| ****************************************************************************** | |
| * 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 | |
| * +----------------+----------------+----------------+----------------+ | |
| * | reserved | 44 | |
| * +----------------+----------------+----------------+----------------+ | |
| * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/| | |
| * +----------------+----------------+----------------+----------------+ | |
| * | 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) | |
| */ | |
| #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; | |
| }; | |
| /* | |
| * 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; | |
| }; | |
| /* | |
| *---------------------------------- 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 | |
| * | |
| *----------------------------------- 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; | |
| uint8_t reserved[56]; | |
| } op; | |
| }; | |
| struct xendispl_resp { | |
| uint16_t id; | |
| uint8_t operation; | |
| uint8_t reserved; | |
| int32_t status; | |
| uint8_t reserved1[56]; | |
| }; | |
| 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__ */ |