1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2012, Microsoft Corporation. 4 * 5 * Author: 6 * Haiyang Zhang <haiyangz@microsoft.com> 7 */ 8 9 /* 10 * Hyper-V Synthetic Video Frame Buffer Driver 11 * 12 * This is the driver for the Hyper-V Synthetic Video, which supports 13 * screen resolution up to Full HD 1920x1080 with 32 bit color on Windows 14 * Server 2012, and 1600x1200 with 16 bit color on Windows Server 2008 R2 15 * or earlier. 16 * 17 * It also solves the double mouse cursor issue of the emulated video mode. 18 * 19 * The default screen resolution is 1152x864, which may be changed by a 20 * kernel parameter: 21 * video=hyperv_fb:<width>x<height> 22 * For example: video=hyperv_fb:1280x1024 23 * 24 * Portrait orientation is also supported: 25 * For example: video=hyperv_fb:864x1152 26 * 27 * When a Windows 10 RS5+ host is used, the virtual machine screen 28 * resolution is obtained from the host. The "video=hyperv_fb" option is 29 * not needed, but still can be used to overwrite what the host specifies. 30 * The VM resolution on the host could be set by executing the powershell 31 * "set-vmvideo" command. For example 32 * set-vmvideo -vmname name -horizontalresolution:1920 \ 33 * -verticalresolution:1200 -resolutiontype single 34 * 35 * Gen 1 VMs also support direct using VM's physical memory for framebuffer. 36 * It could improve the efficiency and performance for framebuffer and VM. 37 * This requires to allocate contiguous physical memory from Linux kernel's 38 * CMA memory allocator. To enable this, supply a kernel parameter to give 39 * enough memory space to CMA allocator for framebuffer. For example: 40 * cma=130m 41 * This gives 130MB memory to CMA allocator that can be allocated to 42 * framebuffer. For reference, 8K resolution (7680x4320) takes about 43 * 127MB memory. 44 */ 45 46 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 47 48 #include <linux/module.h> 49 #include <linux/kernel.h> 50 #include <linux/vmalloc.h> 51 #include <linux/init.h> 52 #include <linux/completion.h> 53 #include <linux/fb.h> 54 #include <linux/pci.h> 55 #include <linux/panic_notifier.h> 56 #include <linux/efi.h> 57 #include <linux/console.h> 58 59 #include <linux/hyperv.h> 60 61 62 /* Hyper-V Synthetic Video Protocol definitions and structures */ 63 #define MAX_VMBUS_PKT_SIZE 0x4000 64 65 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major)) 66 /* Support for VERSION_WIN7 is removed. #define is retained for reference. */ 67 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0) 68 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2) 69 #define SYNTHVID_VERSION_WIN10 SYNTHVID_VERSION(3, 5) 70 71 #define SYNTHVID_VER_GET_MAJOR(ver) (ver & 0x0000ffff) 72 #define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16) 73 74 #define SYNTHVID_DEPTH_WIN8 32 75 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024) 76 77 #define PCI_VENDOR_ID_MICROSOFT 0x1414 78 #define PCI_DEVICE_ID_HYPERV_VIDEO 0x5353 79 80 81 enum pipe_msg_type { 82 PIPE_MSG_INVALID, 83 PIPE_MSG_DATA, 84 PIPE_MSG_MAX 85 }; 86 87 struct pipe_msg_hdr { 88 u32 type; 89 u32 size; /* size of message after this field */ 90 } __packed; 91 92 93 enum synthvid_msg_type { 94 SYNTHVID_ERROR = 0, 95 SYNTHVID_VERSION_REQUEST = 1, 96 SYNTHVID_VERSION_RESPONSE = 2, 97 SYNTHVID_VRAM_LOCATION = 3, 98 SYNTHVID_VRAM_LOCATION_ACK = 4, 99 SYNTHVID_SITUATION_UPDATE = 5, 100 SYNTHVID_SITUATION_UPDATE_ACK = 6, 101 SYNTHVID_POINTER_POSITION = 7, 102 SYNTHVID_POINTER_SHAPE = 8, 103 SYNTHVID_FEATURE_CHANGE = 9, 104 SYNTHVID_DIRT = 10, 105 SYNTHVID_RESOLUTION_REQUEST = 13, 106 SYNTHVID_RESOLUTION_RESPONSE = 14, 107 108 SYNTHVID_MAX = 15 109 }; 110 111 #define SYNTHVID_EDID_BLOCK_SIZE 128 112 #define SYNTHVID_MAX_RESOLUTION_COUNT 64 113 114 struct hvd_screen_info { 115 u16 width; 116 u16 height; 117 } __packed; 118 119 struct synthvid_msg_hdr { 120 u32 type; 121 u32 size; /* size of this header + payload after this field*/ 122 } __packed; 123 124 struct synthvid_version_req { 125 u32 version; 126 } __packed; 127 128 struct synthvid_version_resp { 129 u32 version; 130 u8 is_accepted; 131 u8 max_video_outputs; 132 } __packed; 133 134 struct synthvid_supported_resolution_req { 135 u8 maximum_resolution_count; 136 } __packed; 137 138 struct synthvid_supported_resolution_resp { 139 u8 edid_block[SYNTHVID_EDID_BLOCK_SIZE]; 140 u8 resolution_count; 141 u8 default_resolution_index; 142 u8 is_standard; 143 struct hvd_screen_info 144 supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT]; 145 } __packed; 146 147 struct synthvid_vram_location { 148 u64 user_ctx; 149 u8 is_vram_gpa_specified; 150 u64 vram_gpa; 151 } __packed; 152 153 struct synthvid_vram_location_ack { 154 u64 user_ctx; 155 } __packed; 156 157 struct video_output_situation { 158 u8 active; 159 u32 vram_offset; 160 u8 depth_bits; 161 u32 width_pixels; 162 u32 height_pixels; 163 u32 pitch_bytes; 164 } __packed; 165 166 struct synthvid_situation_update { 167 u64 user_ctx; 168 u8 video_output_count; 169 struct video_output_situation video_output[1]; 170 } __packed; 171 172 struct synthvid_situation_update_ack { 173 u64 user_ctx; 174 } __packed; 175 176 struct synthvid_pointer_position { 177 u8 is_visible; 178 u8 video_output; 179 s32 image_x; 180 s32 image_y; 181 } __packed; 182 183 184 #define CURSOR_MAX_X 96 185 #define CURSOR_MAX_Y 96 186 #define CURSOR_ARGB_PIXEL_SIZE 4 187 #define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE) 188 #define CURSOR_COMPLETE (-1) 189 190 struct synthvid_pointer_shape { 191 u8 part_idx; 192 u8 is_argb; 193 u32 width; /* CURSOR_MAX_X at most */ 194 u32 height; /* CURSOR_MAX_Y at most */ 195 u32 hot_x; /* hotspot relative to upper-left of pointer image */ 196 u32 hot_y; 197 u8 data[4]; 198 } __packed; 199 200 struct synthvid_feature_change { 201 u8 is_dirt_needed; 202 u8 is_ptr_pos_needed; 203 u8 is_ptr_shape_needed; 204 u8 is_situ_needed; 205 } __packed; 206 207 struct rect { 208 s32 x1, y1; /* top left corner */ 209 s32 x2, y2; /* bottom right corner, exclusive */ 210 } __packed; 211 212 struct synthvid_dirt { 213 u8 video_output; 214 u8 dirt_count; 215 struct rect rect[1]; 216 } __packed; 217 218 struct synthvid_msg { 219 struct pipe_msg_hdr pipe_hdr; 220 struct synthvid_msg_hdr vid_hdr; 221 union { 222 struct synthvid_version_req ver_req; 223 struct synthvid_version_resp ver_resp; 224 struct synthvid_vram_location vram; 225 struct synthvid_vram_location_ack vram_ack; 226 struct synthvid_situation_update situ; 227 struct synthvid_situation_update_ack situ_ack; 228 struct synthvid_pointer_position ptr_pos; 229 struct synthvid_pointer_shape ptr_shape; 230 struct synthvid_feature_change feature_chg; 231 struct synthvid_dirt dirt; 232 struct synthvid_supported_resolution_req resolution_req; 233 struct synthvid_supported_resolution_resp resolution_resp; 234 }; 235 } __packed; 236 237 238 /* FB driver definitions and structures */ 239 #define HVFB_WIDTH 1152 /* default screen width */ 240 #define HVFB_HEIGHT 864 /* default screen height */ 241 #define HVFB_WIDTH_MIN 640 242 #define HVFB_HEIGHT_MIN 480 243 244 #define RING_BUFSIZE (256 * 1024) 245 #define VSP_TIMEOUT (10 * HZ) 246 #define HVFB_UPDATE_DELAY (HZ / 20) 247 #define HVFB_ONDEMAND_THROTTLE (HZ / 20) 248 249 struct hvfb_par { 250 struct fb_info *info; 251 struct resource *mem; 252 bool fb_ready; /* fb device is ready */ 253 struct completion wait; 254 u32 synthvid_version; 255 256 struct delayed_work dwork; 257 bool update; 258 bool update_saved; /* The value of 'update' before hibernation */ 259 260 u32 pseudo_palette[16]; 261 u8 init_buf[MAX_VMBUS_PKT_SIZE]; 262 u8 recv_buf[MAX_VMBUS_PKT_SIZE]; 263 264 /* If true, the VSC notifies the VSP on every framebuffer change */ 265 bool synchronous_fb; 266 267 /* If true, need to copy from deferred IO mem to framebuffer mem */ 268 bool need_docopy; 269 270 struct notifier_block hvfb_panic_nb; 271 272 /* Memory for deferred IO and frame buffer itself */ 273 unsigned char *dio_vp; 274 unsigned char *mmio_vp; 275 phys_addr_t mmio_pp; 276 277 /* Dirty rectangle, protected by delayed_refresh_lock */ 278 int x1, y1, x2, y2; 279 bool delayed_refresh; 280 spinlock_t delayed_refresh_lock; 281 }; 282 283 static uint screen_width = HVFB_WIDTH; 284 static uint screen_height = HVFB_HEIGHT; 285 static uint screen_depth; 286 static uint screen_fb_size; 287 static uint dio_fb_size; /* FB size for deferred IO */ 288 289 /* Send message to Hyper-V host */ 290 static inline int synthvid_send(struct hv_device *hdev, 291 struct synthvid_msg *msg) 292 { 293 static atomic64_t request_id = ATOMIC64_INIT(0); 294 int ret; 295 296 msg->pipe_hdr.type = PIPE_MSG_DATA; 297 msg->pipe_hdr.size = msg->vid_hdr.size; 298 299 ret = vmbus_sendpacket(hdev->channel, msg, 300 msg->vid_hdr.size + sizeof(struct pipe_msg_hdr), 301 atomic64_inc_return(&request_id), 302 VM_PKT_DATA_INBAND, 0); 303 304 if (ret) 305 pr_err_ratelimited("Unable to send packet via vmbus; error %d\n", ret); 306 307 return ret; 308 } 309 310 311 /* Send screen resolution info to host */ 312 static int synthvid_send_situ(struct hv_device *hdev) 313 { 314 struct fb_info *info = hv_get_drvdata(hdev); 315 struct synthvid_msg msg; 316 317 if (!info) 318 return -ENODEV; 319 320 memset(&msg, 0, sizeof(struct synthvid_msg)); 321 322 msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE; 323 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 324 sizeof(struct synthvid_situation_update); 325 msg.situ.user_ctx = 0; 326 msg.situ.video_output_count = 1; 327 msg.situ.video_output[0].active = 1; 328 msg.situ.video_output[0].vram_offset = 0; 329 msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel; 330 msg.situ.video_output[0].width_pixels = info->var.xres; 331 msg.situ.video_output[0].height_pixels = info->var.yres; 332 msg.situ.video_output[0].pitch_bytes = info->fix.line_length; 333 334 synthvid_send(hdev, &msg); 335 336 return 0; 337 } 338 339 /* Send mouse pointer info to host */ 340 static int synthvid_send_ptr(struct hv_device *hdev) 341 { 342 struct synthvid_msg msg; 343 344 memset(&msg, 0, sizeof(struct synthvid_msg)); 345 msg.vid_hdr.type = SYNTHVID_POINTER_POSITION; 346 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 347 sizeof(struct synthvid_pointer_position); 348 msg.ptr_pos.is_visible = 1; 349 msg.ptr_pos.video_output = 0; 350 msg.ptr_pos.image_x = 0; 351 msg.ptr_pos.image_y = 0; 352 synthvid_send(hdev, &msg); 353 354 memset(&msg, 0, sizeof(struct synthvid_msg)); 355 msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE; 356 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 357 sizeof(struct synthvid_pointer_shape); 358 msg.ptr_shape.part_idx = CURSOR_COMPLETE; 359 msg.ptr_shape.is_argb = 1; 360 msg.ptr_shape.width = 1; 361 msg.ptr_shape.height = 1; 362 msg.ptr_shape.hot_x = 0; 363 msg.ptr_shape.hot_y = 0; 364 msg.ptr_shape.data[0] = 0; 365 msg.ptr_shape.data[1] = 1; 366 msg.ptr_shape.data[2] = 1; 367 msg.ptr_shape.data[3] = 1; 368 synthvid_send(hdev, &msg); 369 370 return 0; 371 } 372 373 /* Send updated screen area (dirty rectangle) location to host */ 374 static int 375 synthvid_update(struct fb_info *info, int x1, int y1, int x2, int y2) 376 { 377 struct hv_device *hdev = device_to_hv_device(info->device); 378 struct synthvid_msg msg; 379 380 memset(&msg, 0, sizeof(struct synthvid_msg)); 381 if (x2 == INT_MAX) 382 x2 = info->var.xres; 383 if (y2 == INT_MAX) 384 y2 = info->var.yres; 385 386 msg.vid_hdr.type = SYNTHVID_DIRT; 387 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 388 sizeof(struct synthvid_dirt); 389 msg.dirt.video_output = 0; 390 msg.dirt.dirt_count = 1; 391 msg.dirt.rect[0].x1 = (x1 > x2) ? 0 : x1; 392 msg.dirt.rect[0].y1 = (y1 > y2) ? 0 : y1; 393 msg.dirt.rect[0].x2 = 394 (x2 < x1 || x2 > info->var.xres) ? info->var.xres : x2; 395 msg.dirt.rect[0].y2 = 396 (y2 < y1 || y2 > info->var.yres) ? info->var.yres : y2; 397 398 synthvid_send(hdev, &msg); 399 400 return 0; 401 } 402 403 static void hvfb_docopy(struct hvfb_par *par, 404 unsigned long offset, 405 unsigned long size) 406 { 407 if (!par || !par->mmio_vp || !par->dio_vp || !par->fb_ready || 408 size == 0 || offset >= dio_fb_size) 409 return; 410 411 if (offset + size > dio_fb_size) 412 size = dio_fb_size - offset; 413 414 memcpy(par->mmio_vp + offset, par->dio_vp + offset, size); 415 } 416 417 /* Deferred IO callback */ 418 static void synthvid_deferred_io(struct fb_info *p, struct list_head *pagereflist) 419 { 420 struct hvfb_par *par = p->par; 421 struct fb_deferred_io_pageref *pageref; 422 unsigned long start, end; 423 int y1, y2, miny, maxy; 424 425 miny = INT_MAX; 426 maxy = 0; 427 428 /* 429 * Merge dirty pages. It is possible that last page cross 430 * over the end of frame buffer row yres. This is taken care of 431 * in synthvid_update function by clamping the y2 432 * value to yres. 433 */ 434 list_for_each_entry(pageref, pagereflist, list) { 435 start = pageref->offset; 436 end = start + PAGE_SIZE - 1; 437 y1 = start / p->fix.line_length; 438 y2 = end / p->fix.line_length; 439 miny = min_t(int, miny, y1); 440 maxy = max_t(int, maxy, y2); 441 442 /* Copy from dio space to mmio address */ 443 if (par->fb_ready && par->need_docopy) 444 hvfb_docopy(par, start, PAGE_SIZE); 445 } 446 447 if (par->fb_ready && par->update) 448 synthvid_update(p, 0, miny, p->var.xres, maxy + 1); 449 } 450 451 static struct fb_deferred_io synthvid_defio = { 452 .delay = HZ / 20, 453 .deferred_io = synthvid_deferred_io, 454 }; 455 456 /* 457 * Actions on received messages from host: 458 * Complete the wait event. 459 * Or, reply with screen and cursor info. 460 */ 461 static void synthvid_recv_sub(struct hv_device *hdev) 462 { 463 struct fb_info *info = hv_get_drvdata(hdev); 464 struct hvfb_par *par; 465 struct synthvid_msg *msg; 466 467 if (!info) 468 return; 469 470 par = info->par; 471 msg = (struct synthvid_msg *)par->recv_buf; 472 473 /* Complete the wait event */ 474 if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE || 475 msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE || 476 msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) { 477 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE); 478 complete(&par->wait); 479 return; 480 } 481 482 /* Reply with screen and cursor info */ 483 if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) { 484 if (par->fb_ready) { 485 synthvid_send_ptr(hdev); 486 synthvid_send_situ(hdev); 487 } 488 489 par->update = msg->feature_chg.is_dirt_needed; 490 if (par->update) 491 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY); 492 } 493 } 494 495 /* Receive callback for messages from the host */ 496 static void synthvid_receive(void *ctx) 497 { 498 struct hv_device *hdev = ctx; 499 struct fb_info *info = hv_get_drvdata(hdev); 500 struct hvfb_par *par; 501 struct synthvid_msg *recv_buf; 502 u32 bytes_recvd; 503 u64 req_id; 504 int ret; 505 506 if (!info) 507 return; 508 509 par = info->par; 510 recv_buf = (struct synthvid_msg *)par->recv_buf; 511 512 do { 513 ret = vmbus_recvpacket(hdev->channel, recv_buf, 514 MAX_VMBUS_PKT_SIZE, 515 &bytes_recvd, &req_id); 516 if (bytes_recvd > 0 && 517 recv_buf->pipe_hdr.type == PIPE_MSG_DATA) 518 synthvid_recv_sub(hdev); 519 } while (bytes_recvd > 0 && ret == 0); 520 } 521 522 /* Check if the ver1 version is equal or greater than ver2 */ 523 static inline bool synthvid_ver_ge(u32 ver1, u32 ver2) 524 { 525 if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) || 526 (SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) && 527 SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2))) 528 return true; 529 530 return false; 531 } 532 533 /* Check synthetic video protocol version with the host */ 534 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver) 535 { 536 struct fb_info *info = hv_get_drvdata(hdev); 537 struct hvfb_par *par = info->par; 538 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf; 539 int ret = 0; 540 unsigned long t; 541 542 memset(msg, 0, sizeof(struct synthvid_msg)); 543 msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST; 544 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 545 sizeof(struct synthvid_version_req); 546 msg->ver_req.version = ver; 547 synthvid_send(hdev, msg); 548 549 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT); 550 if (!t) { 551 pr_err("Time out on waiting version response\n"); 552 ret = -ETIMEDOUT; 553 goto out; 554 } 555 if (!msg->ver_resp.is_accepted) { 556 ret = -ENODEV; 557 goto out; 558 } 559 560 par->synthvid_version = ver; 561 pr_info("Synthvid Version major %d, minor %d\n", 562 SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver)); 563 564 out: 565 return ret; 566 } 567 568 /* Get current resolution from the host */ 569 static int synthvid_get_supported_resolution(struct hv_device *hdev) 570 { 571 struct fb_info *info = hv_get_drvdata(hdev); 572 struct hvfb_par *par = info->par; 573 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf; 574 int ret = 0; 575 unsigned long t; 576 u8 index; 577 578 memset(msg, 0, sizeof(struct synthvid_msg)); 579 msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST; 580 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 581 sizeof(struct synthvid_supported_resolution_req); 582 583 msg->resolution_req.maximum_resolution_count = 584 SYNTHVID_MAX_RESOLUTION_COUNT; 585 synthvid_send(hdev, msg); 586 587 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT); 588 if (!t) { 589 pr_err("Time out on waiting resolution response\n"); 590 ret = -ETIMEDOUT; 591 goto out; 592 } 593 594 if (msg->resolution_resp.resolution_count == 0) { 595 pr_err("No supported resolutions\n"); 596 ret = -ENODEV; 597 goto out; 598 } 599 600 index = msg->resolution_resp.default_resolution_index; 601 if (index >= msg->resolution_resp.resolution_count) { 602 pr_err("Invalid resolution index: %d\n", index); 603 ret = -ENODEV; 604 goto out; 605 } 606 607 screen_width = 608 msg->resolution_resp.supported_resolution[index].width; 609 screen_height = 610 msg->resolution_resp.supported_resolution[index].height; 611 612 out: 613 return ret; 614 } 615 616 /* Connect to VSP (Virtual Service Provider) on host */ 617 static int synthvid_connect_vsp(struct hv_device *hdev) 618 { 619 struct fb_info *info = hv_get_drvdata(hdev); 620 struct hvfb_par *par = info->par; 621 int ret; 622 623 ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE, 624 NULL, 0, synthvid_receive, hdev); 625 if (ret) { 626 pr_err("Unable to open vmbus channel\n"); 627 return ret; 628 } 629 630 /* Negotiate the protocol version with host */ 631 switch (vmbus_proto_version) { 632 case VERSION_WIN10: 633 case VERSION_WIN10_V5: 634 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10); 635 if (!ret) 636 break; 637 fallthrough; 638 case VERSION_WIN8: 639 case VERSION_WIN8_1: 640 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8); 641 break; 642 default: 643 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10); 644 break; 645 } 646 647 if (ret) { 648 pr_err("Synthetic video device version not accepted\n"); 649 goto error; 650 } 651 652 screen_depth = SYNTHVID_DEPTH_WIN8; 653 if (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10)) { 654 ret = synthvid_get_supported_resolution(hdev); 655 if (ret) 656 pr_info("Failed to get supported resolution from host, use default\n"); 657 } 658 659 screen_fb_size = hdev->channel->offermsg.offer. 660 mmio_megabytes * 1024 * 1024; 661 662 return 0; 663 664 error: 665 vmbus_close(hdev->channel); 666 return ret; 667 } 668 669 /* Send VRAM and Situation messages to the host */ 670 static int synthvid_send_config(struct hv_device *hdev) 671 { 672 struct fb_info *info = hv_get_drvdata(hdev); 673 struct hvfb_par *par = info->par; 674 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf; 675 int ret = 0; 676 unsigned long t; 677 678 /* Send VRAM location */ 679 memset(msg, 0, sizeof(struct synthvid_msg)); 680 msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION; 681 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) + 682 sizeof(struct synthvid_vram_location); 683 msg->vram.user_ctx = msg->vram.vram_gpa = par->mmio_pp; 684 msg->vram.is_vram_gpa_specified = 1; 685 synthvid_send(hdev, msg); 686 687 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT); 688 if (!t) { 689 pr_err("Time out on waiting vram location ack\n"); 690 ret = -ETIMEDOUT; 691 goto out; 692 } 693 if (msg->vram_ack.user_ctx != par->mmio_pp) { 694 pr_err("Unable to set VRAM location\n"); 695 ret = -ENODEV; 696 goto out; 697 } 698 699 /* Send pointer and situation update */ 700 synthvid_send_ptr(hdev); 701 synthvid_send_situ(hdev); 702 703 out: 704 return ret; 705 } 706 707 708 /* 709 * Delayed work callback: 710 * It is scheduled to call whenever update request is received and it has 711 * not been called in last HVFB_ONDEMAND_THROTTLE time interval. 712 */ 713 static void hvfb_update_work(struct work_struct *w) 714 { 715 struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work); 716 struct fb_info *info = par->info; 717 unsigned long flags; 718 int x1, x2, y1, y2; 719 int j; 720 721 spin_lock_irqsave(&par->delayed_refresh_lock, flags); 722 /* Reset the request flag */ 723 par->delayed_refresh = false; 724 725 /* Store the dirty rectangle to local variables */ 726 x1 = par->x1; 727 x2 = par->x2; 728 y1 = par->y1; 729 y2 = par->y2; 730 731 /* Clear dirty rectangle */ 732 par->x1 = par->y1 = INT_MAX; 733 par->x2 = par->y2 = 0; 734 735 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags); 736 737 if (x1 > info->var.xres || x2 > info->var.xres || 738 y1 > info->var.yres || y2 > info->var.yres || x2 <= x1) 739 return; 740 741 /* Copy the dirty rectangle to frame buffer memory */ 742 if (par->need_docopy) 743 for (j = y1; j < y2; j++) 744 hvfb_docopy(par, 745 j * info->fix.line_length + 746 (x1 * screen_depth / 8), 747 (x2 - x1) * screen_depth / 8); 748 749 /* Refresh */ 750 if (par->fb_ready && par->update) 751 synthvid_update(info, x1, y1, x2, y2); 752 } 753 754 /* 755 * Control the on-demand refresh frequency. It schedules a delayed 756 * screen update if it has not yet. 757 */ 758 static void hvfb_ondemand_refresh_throttle(struct hvfb_par *par, 759 int x1, int y1, int w, int h) 760 { 761 unsigned long flags; 762 int x2 = x1 + w; 763 int y2 = y1 + h; 764 765 spin_lock_irqsave(&par->delayed_refresh_lock, flags); 766 767 /* Merge dirty rectangle */ 768 par->x1 = min_t(int, par->x1, x1); 769 par->y1 = min_t(int, par->y1, y1); 770 par->x2 = max_t(int, par->x2, x2); 771 par->y2 = max_t(int, par->y2, y2); 772 773 /* Schedule a delayed screen update if not yet */ 774 if (par->delayed_refresh == false) { 775 schedule_delayed_work(&par->dwork, 776 HVFB_ONDEMAND_THROTTLE); 777 par->delayed_refresh = true; 778 } 779 780 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags); 781 } 782 783 static int hvfb_on_panic(struct notifier_block *nb, 784 unsigned long e, void *p) 785 { 786 struct hvfb_par *par; 787 struct fb_info *info; 788 789 par = container_of(nb, struct hvfb_par, hvfb_panic_nb); 790 par->synchronous_fb = true; 791 info = par->info; 792 if (par->need_docopy) 793 hvfb_docopy(par, 0, dio_fb_size); 794 synthvid_update(info, 0, 0, INT_MAX, INT_MAX); 795 796 return NOTIFY_DONE; 797 } 798 799 /* Framebuffer operation handlers */ 800 801 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) 802 { 803 if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN || 804 var->xres > screen_width || var->yres > screen_height || 805 var->bits_per_pixel != screen_depth) 806 return -EINVAL; 807 808 var->xres_virtual = var->xres; 809 var->yres_virtual = var->yres; 810 811 return 0; 812 } 813 814 static int hvfb_set_par(struct fb_info *info) 815 { 816 struct hv_device *hdev = device_to_hv_device(info->device); 817 818 return synthvid_send_situ(hdev); 819 } 820 821 822 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf) 823 { 824 return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset; 825 } 826 827 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green, 828 unsigned blue, unsigned transp, struct fb_info *info) 829 { 830 u32 *pal = info->pseudo_palette; 831 832 if (regno > 15) 833 return -EINVAL; 834 835 pal[regno] = chan_to_field(red, &info->var.red) 836 | chan_to_field(green, &info->var.green) 837 | chan_to_field(blue, &info->var.blue) 838 | chan_to_field(transp, &info->var.transp); 839 840 return 0; 841 } 842 843 static int hvfb_blank(int blank, struct fb_info *info) 844 { 845 return 1; /* get fb_blank to set the colormap to all black */ 846 } 847 848 static void hvfb_cfb_fillrect(struct fb_info *p, 849 const struct fb_fillrect *rect) 850 { 851 struct hvfb_par *par = p->par; 852 853 cfb_fillrect(p, rect); 854 if (par->synchronous_fb) 855 synthvid_update(p, 0, 0, INT_MAX, INT_MAX); 856 else 857 hvfb_ondemand_refresh_throttle(par, rect->dx, rect->dy, 858 rect->width, rect->height); 859 } 860 861 static void hvfb_cfb_copyarea(struct fb_info *p, 862 const struct fb_copyarea *area) 863 { 864 struct hvfb_par *par = p->par; 865 866 cfb_copyarea(p, area); 867 if (par->synchronous_fb) 868 synthvid_update(p, 0, 0, INT_MAX, INT_MAX); 869 else 870 hvfb_ondemand_refresh_throttle(par, area->dx, area->dy, 871 area->width, area->height); 872 } 873 874 static void hvfb_cfb_imageblit(struct fb_info *p, 875 const struct fb_image *image) 876 { 877 struct hvfb_par *par = p->par; 878 879 cfb_imageblit(p, image); 880 if (par->synchronous_fb) 881 synthvid_update(p, 0, 0, INT_MAX, INT_MAX); 882 else 883 hvfb_ondemand_refresh_throttle(par, image->dx, image->dy, 884 image->width, image->height); 885 } 886 887 static const struct fb_ops hvfb_ops = { 888 .owner = THIS_MODULE, 889 .fb_check_var = hvfb_check_var, 890 .fb_set_par = hvfb_set_par, 891 .fb_setcolreg = hvfb_setcolreg, 892 .fb_fillrect = hvfb_cfb_fillrect, 893 .fb_copyarea = hvfb_cfb_copyarea, 894 .fb_imageblit = hvfb_cfb_imageblit, 895 .fb_blank = hvfb_blank, 896 .fb_mmap = fb_deferred_io_mmap, 897 }; 898 899 900 /* Get options from kernel paramenter "video=" */ 901 static void hvfb_get_option(struct fb_info *info) 902 { 903 struct hvfb_par *par = info->par; 904 char *opt = NULL, *p; 905 uint x = 0, y = 0; 906 907 if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt) 908 return; 909 910 p = strsep(&opt, "x"); 911 if (!*p || kstrtouint(p, 0, &x) || 912 !opt || !*opt || kstrtouint(opt, 0, &y)) { 913 pr_err("Screen option is invalid: skipped\n"); 914 return; 915 } 916 917 if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN || 918 (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10) && 919 (x * y * screen_depth / 8 > screen_fb_size)) || 920 (par->synthvid_version == SYNTHVID_VERSION_WIN8 && 921 x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8)) { 922 pr_err("Screen resolution option is out of range: skipped\n"); 923 return; 924 } 925 926 screen_width = x; 927 screen_height = y; 928 return; 929 } 930 931 /* 932 * Allocate enough contiguous physical memory. 933 * Return physical address if succeeded or -1 if failed. 934 */ 935 static phys_addr_t hvfb_get_phymem(struct hv_device *hdev, 936 unsigned int request_size) 937 { 938 struct page *page = NULL; 939 dma_addr_t dma_handle; 940 void *vmem; 941 phys_addr_t paddr = 0; 942 unsigned int order = get_order(request_size); 943 944 if (request_size == 0) 945 return -1; 946 947 if (order < MAX_ORDER) { 948 /* Call alloc_pages if the size is less than 2^MAX_ORDER */ 949 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); 950 if (!page) 951 return -1; 952 953 paddr = (page_to_pfn(page) << PAGE_SHIFT); 954 } else { 955 /* Allocate from CMA */ 956 hdev->device.coherent_dma_mask = DMA_BIT_MASK(64); 957 958 vmem = dma_alloc_coherent(&hdev->device, 959 round_up(request_size, PAGE_SIZE), 960 &dma_handle, 961 GFP_KERNEL | __GFP_NOWARN); 962 963 if (!vmem) 964 return -1; 965 966 paddr = virt_to_phys(vmem); 967 } 968 969 return paddr; 970 } 971 972 /* Release contiguous physical memory */ 973 static void hvfb_release_phymem(struct hv_device *hdev, 974 phys_addr_t paddr, unsigned int size) 975 { 976 unsigned int order = get_order(size); 977 978 if (order < MAX_ORDER) 979 __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order); 980 else 981 dma_free_coherent(&hdev->device, 982 round_up(size, PAGE_SIZE), 983 phys_to_virt(paddr), 984 paddr); 985 } 986 987 988 /* Get framebuffer memory from Hyper-V video pci space */ 989 static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info) 990 { 991 struct hvfb_par *par = info->par; 992 struct pci_dev *pdev = NULL; 993 void __iomem *fb_virt; 994 int gen2vm = efi_enabled(EFI_BOOT); 995 resource_size_t pot_start, pot_end; 996 phys_addr_t paddr; 997 int ret; 998 999 info->apertures = alloc_apertures(1); 1000 if (!info->apertures) 1001 return -ENOMEM; 1002 1003 if (!gen2vm) { 1004 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT, 1005 PCI_DEVICE_ID_HYPERV_VIDEO, NULL); 1006 if (!pdev) { 1007 pr_err("Unable to find PCI Hyper-V video\n"); 1008 return -ENODEV; 1009 } 1010 1011 info->apertures->ranges[0].base = pci_resource_start(pdev, 0); 1012 info->apertures->ranges[0].size = pci_resource_len(pdev, 0); 1013 1014 /* 1015 * For Gen 1 VM, we can directly use the contiguous memory 1016 * from VM. If we succeed, deferred IO happens directly 1017 * on this allocated framebuffer memory, avoiding extra 1018 * memory copy. 1019 */ 1020 paddr = hvfb_get_phymem(hdev, screen_fb_size); 1021 if (paddr != (phys_addr_t) -1) { 1022 par->mmio_pp = paddr; 1023 par->mmio_vp = par->dio_vp = __va(paddr); 1024 1025 info->fix.smem_start = paddr; 1026 info->fix.smem_len = screen_fb_size; 1027 info->screen_base = par->mmio_vp; 1028 info->screen_size = screen_fb_size; 1029 1030 par->need_docopy = false; 1031 goto getmem_done; 1032 } 1033 pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n"); 1034 } else { 1035 info->apertures->ranges[0].base = screen_info.lfb_base; 1036 info->apertures->ranges[0].size = screen_info.lfb_size; 1037 } 1038 1039 /* 1040 * Cannot use the contiguous physical memory. 1041 * Allocate mmio space for framebuffer. 1042 */ 1043 dio_fb_size = 1044 screen_width * screen_height * screen_depth / 8; 1045 1046 if (gen2vm) { 1047 pot_start = 0; 1048 pot_end = -1; 1049 } else { 1050 if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) || 1051 pci_resource_len(pdev, 0) < screen_fb_size) { 1052 pr_err("Resource not available or (0x%lx < 0x%lx)\n", 1053 (unsigned long) pci_resource_len(pdev, 0), 1054 (unsigned long) screen_fb_size); 1055 goto err1; 1056 } 1057 1058 pot_end = pci_resource_end(pdev, 0); 1059 pot_start = pot_end - screen_fb_size + 1; 1060 } 1061 1062 ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end, 1063 screen_fb_size, 0x100000, true); 1064 if (ret != 0) { 1065 pr_err("Unable to allocate framebuffer memory\n"); 1066 goto err1; 1067 } 1068 1069 /* 1070 * Map the VRAM cacheable for performance. This is also required for 1071 * VM Connect to display properly for ARM64 Linux VM, as the host also 1072 * maps the VRAM cacheable. 1073 */ 1074 fb_virt = ioremap_cache(par->mem->start, screen_fb_size); 1075 if (!fb_virt) 1076 goto err2; 1077 1078 /* Allocate memory for deferred IO */ 1079 par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE)); 1080 if (par->dio_vp == NULL) 1081 goto err3; 1082 1083 /* Physical address of FB device */ 1084 par->mmio_pp = par->mem->start; 1085 /* Virtual address of FB device */ 1086 par->mmio_vp = (unsigned char *) fb_virt; 1087 1088 info->fix.smem_start = par->mem->start; 1089 info->fix.smem_len = dio_fb_size; 1090 info->screen_base = par->dio_vp; 1091 info->screen_size = dio_fb_size; 1092 1093 getmem_done: 1094 remove_conflicting_framebuffers(info->apertures, 1095 KBUILD_MODNAME, false); 1096 1097 if (gen2vm) { 1098 /* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */ 1099 screen_info.lfb_size = 0; 1100 screen_info.lfb_base = 0; 1101 screen_info.orig_video_isVGA = 0; 1102 } else { 1103 pci_dev_put(pdev); 1104 } 1105 1106 return 0; 1107 1108 err3: 1109 iounmap(fb_virt); 1110 err2: 1111 vmbus_free_mmio(par->mem->start, screen_fb_size); 1112 par->mem = NULL; 1113 err1: 1114 if (!gen2vm) 1115 pci_dev_put(pdev); 1116 1117 return -ENOMEM; 1118 } 1119 1120 /* Release the framebuffer */ 1121 static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info) 1122 { 1123 struct hvfb_par *par = info->par; 1124 1125 if (par->need_docopy) { 1126 vfree(par->dio_vp); 1127 iounmap(info->screen_base); 1128 vmbus_free_mmio(par->mem->start, screen_fb_size); 1129 } else { 1130 hvfb_release_phymem(hdev, info->fix.smem_start, 1131 screen_fb_size); 1132 } 1133 1134 par->mem = NULL; 1135 } 1136 1137 1138 static int hvfb_probe(struct hv_device *hdev, 1139 const struct hv_vmbus_device_id *dev_id) 1140 { 1141 struct fb_info *info; 1142 struct hvfb_par *par; 1143 int ret; 1144 1145 info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device); 1146 if (!info) 1147 return -ENOMEM; 1148 1149 par = info->par; 1150 par->info = info; 1151 par->fb_ready = false; 1152 par->need_docopy = true; 1153 init_completion(&par->wait); 1154 INIT_DELAYED_WORK(&par->dwork, hvfb_update_work); 1155 1156 par->delayed_refresh = false; 1157 spin_lock_init(&par->delayed_refresh_lock); 1158 par->x1 = par->y1 = INT_MAX; 1159 par->x2 = par->y2 = 0; 1160 1161 /* Connect to VSP */ 1162 hv_set_drvdata(hdev, info); 1163 ret = synthvid_connect_vsp(hdev); 1164 if (ret) { 1165 pr_err("Unable to connect to VSP\n"); 1166 goto error1; 1167 } 1168 1169 hvfb_get_option(info); 1170 pr_info("Screen resolution: %dx%d, Color depth: %d, Frame buffer size: %d\n", 1171 screen_width, screen_height, screen_depth, screen_fb_size); 1172 1173 ret = hvfb_getmem(hdev, info); 1174 if (ret) { 1175 pr_err("No memory for framebuffer\n"); 1176 goto error2; 1177 } 1178 1179 /* Set up fb_info */ 1180 info->flags = FBINFO_DEFAULT; 1181 1182 info->var.xres_virtual = info->var.xres = screen_width; 1183 info->var.yres_virtual = info->var.yres = screen_height; 1184 info->var.bits_per_pixel = screen_depth; 1185 1186 if (info->var.bits_per_pixel == 16) { 1187 info->var.red = (struct fb_bitfield){11, 5, 0}; 1188 info->var.green = (struct fb_bitfield){5, 6, 0}; 1189 info->var.blue = (struct fb_bitfield){0, 5, 0}; 1190 info->var.transp = (struct fb_bitfield){0, 0, 0}; 1191 } else { 1192 info->var.red = (struct fb_bitfield){16, 8, 0}; 1193 info->var.green = (struct fb_bitfield){8, 8, 0}; 1194 info->var.blue = (struct fb_bitfield){0, 8, 0}; 1195 info->var.transp = (struct fb_bitfield){24, 8, 0}; 1196 } 1197 1198 info->var.activate = FB_ACTIVATE_NOW; 1199 info->var.height = -1; 1200 info->var.width = -1; 1201 info->var.vmode = FB_VMODE_NONINTERLACED; 1202 1203 strcpy(info->fix.id, KBUILD_MODNAME); 1204 info->fix.type = FB_TYPE_PACKED_PIXELS; 1205 info->fix.visual = FB_VISUAL_TRUECOLOR; 1206 info->fix.line_length = screen_width * screen_depth / 8; 1207 info->fix.accel = FB_ACCEL_NONE; 1208 1209 info->fbops = &hvfb_ops; 1210 info->pseudo_palette = par->pseudo_palette; 1211 1212 /* Initialize deferred IO */ 1213 info->fbdefio = &synthvid_defio; 1214 fb_deferred_io_init(info); 1215 1216 /* Send config to host */ 1217 ret = synthvid_send_config(hdev); 1218 if (ret) 1219 goto error; 1220 1221 ret = register_framebuffer(info); 1222 if (ret) { 1223 pr_err("Unable to register framebuffer\n"); 1224 goto error; 1225 } 1226 1227 par->fb_ready = true; 1228 1229 par->synchronous_fb = false; 1230 par->hvfb_panic_nb.notifier_call = hvfb_on_panic; 1231 atomic_notifier_chain_register(&panic_notifier_list, 1232 &par->hvfb_panic_nb); 1233 1234 return 0; 1235 1236 error: 1237 fb_deferred_io_cleanup(info); 1238 hvfb_putmem(hdev, info); 1239 error2: 1240 vmbus_close(hdev->channel); 1241 error1: 1242 cancel_delayed_work_sync(&par->dwork); 1243 hv_set_drvdata(hdev, NULL); 1244 framebuffer_release(info); 1245 return ret; 1246 } 1247 1248 1249 static int hvfb_remove(struct hv_device *hdev) 1250 { 1251 struct fb_info *info = hv_get_drvdata(hdev); 1252 struct hvfb_par *par = info->par; 1253 1254 atomic_notifier_chain_unregister(&panic_notifier_list, 1255 &par->hvfb_panic_nb); 1256 1257 par->update = false; 1258 par->fb_ready = false; 1259 1260 fb_deferred_io_cleanup(info); 1261 1262 unregister_framebuffer(info); 1263 cancel_delayed_work_sync(&par->dwork); 1264 1265 vmbus_close(hdev->channel); 1266 hv_set_drvdata(hdev, NULL); 1267 1268 hvfb_putmem(hdev, info); 1269 framebuffer_release(info); 1270 1271 return 0; 1272 } 1273 1274 static int hvfb_suspend(struct hv_device *hdev) 1275 { 1276 struct fb_info *info = hv_get_drvdata(hdev); 1277 struct hvfb_par *par = info->par; 1278 1279 console_lock(); 1280 1281 /* 1 means do suspend */ 1282 fb_set_suspend(info, 1); 1283 1284 cancel_delayed_work_sync(&par->dwork); 1285 cancel_delayed_work_sync(&info->deferred_work); 1286 1287 par->update_saved = par->update; 1288 par->update = false; 1289 par->fb_ready = false; 1290 1291 vmbus_close(hdev->channel); 1292 1293 console_unlock(); 1294 1295 return 0; 1296 } 1297 1298 static int hvfb_resume(struct hv_device *hdev) 1299 { 1300 struct fb_info *info = hv_get_drvdata(hdev); 1301 struct hvfb_par *par = info->par; 1302 int ret; 1303 1304 console_lock(); 1305 1306 ret = synthvid_connect_vsp(hdev); 1307 if (ret != 0) 1308 goto out; 1309 1310 ret = synthvid_send_config(hdev); 1311 if (ret != 0) { 1312 vmbus_close(hdev->channel); 1313 goto out; 1314 } 1315 1316 par->fb_ready = true; 1317 par->update = par->update_saved; 1318 1319 schedule_delayed_work(&info->deferred_work, info->fbdefio->delay); 1320 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY); 1321 1322 /* 0 means do resume */ 1323 fb_set_suspend(info, 0); 1324 1325 out: 1326 console_unlock(); 1327 1328 return ret; 1329 } 1330 1331 1332 static const struct pci_device_id pci_stub_id_table[] = { 1333 { 1334 .vendor = PCI_VENDOR_ID_MICROSOFT, 1335 .device = PCI_DEVICE_ID_HYPERV_VIDEO, 1336 }, 1337 { /* end of list */ } 1338 }; 1339 1340 static const struct hv_vmbus_device_id id_table[] = { 1341 /* Synthetic Video Device GUID */ 1342 {HV_SYNTHVID_GUID}, 1343 {} 1344 }; 1345 1346 MODULE_DEVICE_TABLE(pci, pci_stub_id_table); 1347 MODULE_DEVICE_TABLE(vmbus, id_table); 1348 1349 static struct hv_driver hvfb_drv = { 1350 .name = KBUILD_MODNAME, 1351 .id_table = id_table, 1352 .probe = hvfb_probe, 1353 .remove = hvfb_remove, 1354 .suspend = hvfb_suspend, 1355 .resume = hvfb_resume, 1356 .driver = { 1357 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1358 }, 1359 }; 1360 1361 static int hvfb_pci_stub_probe(struct pci_dev *pdev, 1362 const struct pci_device_id *ent) 1363 { 1364 return 0; 1365 } 1366 1367 static void hvfb_pci_stub_remove(struct pci_dev *pdev) 1368 { 1369 } 1370 1371 static struct pci_driver hvfb_pci_stub_driver = { 1372 .name = KBUILD_MODNAME, 1373 .id_table = pci_stub_id_table, 1374 .probe = hvfb_pci_stub_probe, 1375 .remove = hvfb_pci_stub_remove, 1376 .driver = { 1377 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 1378 } 1379 }; 1380 1381 static int __init hvfb_drv_init(void) 1382 { 1383 int ret; 1384 1385 ret = vmbus_driver_register(&hvfb_drv); 1386 if (ret != 0) 1387 return ret; 1388 1389 ret = pci_register_driver(&hvfb_pci_stub_driver); 1390 if (ret != 0) { 1391 vmbus_driver_unregister(&hvfb_drv); 1392 return ret; 1393 } 1394 1395 return 0; 1396 } 1397 1398 static void __exit hvfb_drv_exit(void) 1399 { 1400 pci_unregister_driver(&hvfb_pci_stub_driver); 1401 vmbus_driver_unregister(&hvfb_drv); 1402 } 1403 1404 module_init(hvfb_drv_init); 1405 module_exit(hvfb_drv_exit); 1406 1407 MODULE_LICENSE("GPL"); 1408 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver"); 1409