drivers/video/fbdev/hyperv_fb.c

   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/init.h>
  51 #include <linux/completion.h>
  52 #include <linux/fb.h>
  53 #include <linux/pci.h>
  54 #include <linux/efi.h>
  55 #include <linux/console.h>
  56
  57 #include <linux/hyperv.h>
  58
  59
  60 /* Hyper-V Synthetic Video Protocol definitions and structures */
  61 #define MAX_VMBUS_PKT_SIZE 0x4000
  62
  63 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
  64 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
  65 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
  66 #define SYNTHVID_VERSION_WIN10 SYNTHVID_VERSION(3, 5)
  67
  68 #define SYNTHVID_VER_GET_MAJOR(ver) (ver & 0x0000ffff)
  69 #define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16)
  70
  71 #define SYNTHVID_DEPTH_WIN7 16
  72 #define SYNTHVID_DEPTH_WIN8 32
  73
  74 #define SYNTHVID_FB_SIZE_WIN7 (4 * 1024 * 1024)
  75 #define SYNTHVID_WIDTH_MAX_WIN7 1600
  76 #define SYNTHVID_HEIGHT_MAX_WIN7 1200
  77
  78 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
  79
  80 #define PCI_VENDOR_ID_MICROSOFT 0x1414
  81 #define PCI_DEVICE_ID_HYPERV_VIDEO 0x5353
  82
  83
  84 enum pipe_msg_type {
  85         PIPE_MSG_INVALID,
  86         PIPE_MSG_DATA,
  87         PIPE_MSG_MAX
  88 };
  89
  90 struct pipe_msg_hdr {
  91         u32 type;
  92         u32 size; /* size of message after this field */
  93 } __packed;
  94
  95
  96 enum synthvid_msg_type {
  97         SYNTHVID_ERROR                  = 0,
  98         SYNTHVID_VERSION_REQUEST        = 1,
  99         SYNTHVID_VERSION_RESPONSE       = 2,
 100         SYNTHVID_VRAM_LOCATION          = 3,
 101         SYNTHVID_VRAM_LOCATION_ACK      = 4,
 102         SYNTHVID_SITUATION_UPDATE       = 5,
 103         SYNTHVID_SITUATION_UPDATE_ACK   = 6,
 104         SYNTHVID_POINTER_POSITION       = 7,
 105         SYNTHVID_POINTER_SHAPE          = 8,
 106         SYNTHVID_FEATURE_CHANGE         = 9,
 107         SYNTHVID_DIRT                   = 10,
 108         SYNTHVID_RESOLUTION_REQUEST     = 13,
 109         SYNTHVID_RESOLUTION_RESPONSE    = 14,
 110
 111         SYNTHVID_MAX                    = 15
 112 };
 113
 114 #define         SYNTHVID_EDID_BLOCK_SIZE        128
 115 #define         SYNTHVID_MAX_RESOLUTION_COUNT   64
 116
 117 struct hvd_screen_info {
 118         u16 width;
 119         u16 height;
 120 } __packed;
 121
 122 struct synthvid_msg_hdr {
 123         u32 type;
 124         u32 size;  /* size of this header + payload after this field*/
 125 } __packed;
 126
 127 struct synthvid_version_req {
 128         u32 version;
 129 } __packed;
 130
 131 struct synthvid_version_resp {
 132         u32 version;
 133         u8 is_accepted;
 134         u8 max_video_outputs;
 135 } __packed;
 136
 137 struct synthvid_supported_resolution_req {
 138         u8 maximum_resolution_count;
 139 } __packed;
 140
 141 struct synthvid_supported_resolution_resp {
 142         u8 edid_block[SYNTHVID_EDID_BLOCK_SIZE];
 143         u8 resolution_count;
 144         u8 default_resolution_index;
 145         u8 is_standard;
 146         struct hvd_screen_info
 147                 supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT];
 148 } __packed;
 149
 150 struct synthvid_vram_location {
 151         u64 user_ctx;
 152         u8 is_vram_gpa_specified;
 153         u64 vram_gpa;
 154 } __packed;
 155
 156 struct synthvid_vram_location_ack {
 157         u64 user_ctx;
 158 } __packed;
 159
 160 struct video_output_situation {
 161         u8 active;
 162         u32 vram_offset;
 163         u8 depth_bits;
 164         u32 width_pixels;
 165         u32 height_pixels;
 166         u32 pitch_bytes;
 167 } __packed;
 168
 169 struct synthvid_situation_update {
 170         u64 user_ctx;
 171         u8 video_output_count;
 172         struct video_output_situation video_output[1];
 173 } __packed;
 174
 175 struct synthvid_situation_update_ack {
 176         u64 user_ctx;
 177 } __packed;
 178
 179 struct synthvid_pointer_position {
 180         u8 is_visible;
 181         u8 video_output;
 182         s32 image_x;
 183         s32 image_y;
 184 } __packed;
 185
 186
 187 #define CURSOR_MAX_X 96
 188 #define CURSOR_MAX_Y 96
 189 #define CURSOR_ARGB_PIXEL_SIZE 4
 190 #define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE)
 191 #define CURSOR_COMPLETE (-1)
 192
 193 struct synthvid_pointer_shape {
 194         u8 part_idx;
 195         u8 is_argb;
 196         u32 width; /* CURSOR_MAX_X at most */
 197         u32 height; /* CURSOR_MAX_Y at most */
 198         u32 hot_x; /* hotspot relative to upper-left of pointer image */
 199         u32 hot_y;
 200         u8 data[4];
 201 } __packed;
 202
 203 struct synthvid_feature_change {
 204         u8 is_dirt_needed;
 205         u8 is_ptr_pos_needed;
 206         u8 is_ptr_shape_needed;
 207         u8 is_situ_needed;
 208 } __packed;
 209
 210 struct rect {
 211         s32 x1, y1; /* top left corner */
 212         s32 x2, y2; /* bottom right corner, exclusive */
 213 } __packed;
 214
 215 struct synthvid_dirt {
 216         u8 video_output;
 217         u8 dirt_count;
 218         struct rect rect[1];
 219 } __packed;
 220
 221 struct synthvid_msg {
 222         struct pipe_msg_hdr pipe_hdr;
 223         struct synthvid_msg_hdr vid_hdr;
 224         union {
 225                 struct synthvid_version_req ver_req;
 226                 struct synthvid_version_resp ver_resp;
 227                 struct synthvid_vram_location vram;
 228                 struct synthvid_vram_location_ack vram_ack;
 229                 struct synthvid_situation_update situ;
 230                 struct synthvid_situation_update_ack situ_ack;
 231                 struct synthvid_pointer_position ptr_pos;
 232                 struct synthvid_pointer_shape ptr_shape;
 233                 struct synthvid_feature_change feature_chg;
 234                 struct synthvid_dirt dirt;
 235                 struct synthvid_supported_resolution_req resolution_req;
 236                 struct synthvid_supported_resolution_resp resolution_resp;
 237         };
 238 } __packed;
 239
 240
 241 /* FB driver definitions and structures */
 242 #define HVFB_WIDTH 1152 /* default screen width */
 243 #define HVFB_HEIGHT 864 /* default screen height */
 244 #define HVFB_WIDTH_MIN 640
 245 #define HVFB_HEIGHT_MIN 480
 246
 247 #define RING_BUFSIZE (256 * 1024)
 248 #define VSP_TIMEOUT (10 * HZ)
 249 #define HVFB_UPDATE_DELAY (HZ / 20)
 250 #define HVFB_ONDEMAND_THROTTLE (HZ / 20)
 251
 252 struct hvfb_par {
 253         struct fb_info *info;
 254         struct resource *mem;
 255         bool fb_ready; /* fb device is ready */
 256         struct completion wait;
 257         u32 synthvid_version;
 258
 259         struct delayed_work dwork;
 260         bool update;
 261         bool update_saved; /* The value of 'update' before hibernation */
 262
 263         u32 pseudo_palette[16];
 264         u8 init_buf[MAX_VMBUS_PKT_SIZE];
 265         u8 recv_buf[MAX_VMBUS_PKT_SIZE];
 266
 267         /* If true, the VSC notifies the VSP on every framebuffer change */
 268         bool synchronous_fb;
 269
 270         /* If true, need to copy from deferred IO mem to framebuffer mem */
 271         bool need_docopy;
 272
 273         struct notifier_block hvfb_panic_nb;
 274
 275         /* Memory for deferred IO and frame buffer itself */
 276         unsigned char *dio_vp;
 277         unsigned char *mmio_vp;
 278         phys_addr_t mmio_pp;
 279
 280         /* Dirty rectangle, protected by delayed_refresh_lock */
 281         int x1, y1, x2, y2;
 282         bool delayed_refresh;
 283         spinlock_t delayed_refresh_lock;
 284 };
 285
 286 static uint screen_width = HVFB_WIDTH;
 287 static uint screen_height = HVFB_HEIGHT;
 288 static uint screen_width_max = HVFB_WIDTH;
 289 static uint screen_height_max = HVFB_HEIGHT;
 290 static uint screen_depth;
 291 static uint screen_fb_size;
 292 static uint dio_fb_size; /* FB size for deferred IO */
 293
 294 /* Send message to Hyper-V host */
 295 static inline int synthvid_send(struct hv_device *hdev,
 296                                 struct synthvid_msg *msg)
 297 {
 298         static atomic64_t request_id = ATOMIC64_INIT(0);
 299         int ret;
 300
 301         msg->pipe_hdr.type = PIPE_MSG_DATA;
 302         msg->pipe_hdr.size = msg->vid_hdr.size;
 303
 304         ret = vmbus_sendpacket(hdev->channel, msg,
 305                                msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
 306                                atomic64_inc_return(&request_id),
 307                                VM_PKT_DATA_INBAND, 0);
 308
 309         if (ret)
 310                 pr_err("Unable to send packet via vmbus\n");
 311
 312         return ret;
 313 }
 314
 315
 316 /* Send screen resolution info to host */
 317 static int synthvid_send_situ(struct hv_device *hdev)
 318 {
 319         struct fb_info *info = hv_get_drvdata(hdev);
 320         struct synthvid_msg msg;
 321
 322         if (!info)
 323                 return -ENODEV;
 324
 325         memset(&msg, 0, sizeof(struct synthvid_msg));
 326
 327         msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
 328         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 329                 sizeof(struct synthvid_situation_update);
 330         msg.situ.user_ctx = 0;
 331         msg.situ.video_output_count = 1;
 332         msg.situ.video_output[0].active = 1;
 333         msg.situ.video_output[0].vram_offset = 0;
 334         msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
 335         msg.situ.video_output[0].width_pixels = info->var.xres;
 336         msg.situ.video_output[0].height_pixels = info->var.yres;
 337         msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
 338
 339         synthvid_send(hdev, &msg);
 340
 341         return 0;
 342 }
 343
 344 /* Send mouse pointer info to host */
 345 static int synthvid_send_ptr(struct hv_device *hdev)
 346 {
 347         struct synthvid_msg msg;
 348
 349         memset(&msg, 0, sizeof(struct synthvid_msg));
 350         msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
 351         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 352                 sizeof(struct synthvid_pointer_position);
 353         msg.ptr_pos.is_visible = 1;
 354         msg.ptr_pos.video_output = 0;
 355         msg.ptr_pos.image_x = 0;
 356         msg.ptr_pos.image_y = 0;
 357         synthvid_send(hdev, &msg);
 358
 359         memset(&msg, 0, sizeof(struct synthvid_msg));
 360         msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
 361         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 362                 sizeof(struct synthvid_pointer_shape);
 363         msg.ptr_shape.part_idx = CURSOR_COMPLETE;
 364         msg.ptr_shape.is_argb = 1;
 365         msg.ptr_shape.width = 1;
 366         msg.ptr_shape.height = 1;
 367         msg.ptr_shape.hot_x = 0;
 368         msg.ptr_shape.hot_y = 0;
 369         msg.ptr_shape.data[0] = 0;
 370         msg.ptr_shape.data[1] = 1;
 371         msg.ptr_shape.data[2] = 1;
 372         msg.ptr_shape.data[3] = 1;
 373         synthvid_send(hdev, &msg);
 374
 375         return 0;
 376 }
 377
 378 /* Send updated screen area (dirty rectangle) location to host */
 379 static int
 380 synthvid_update(struct fb_info *info, int x1, int y1, int x2, int y2)
 381 {
 382         struct hv_device *hdev = device_to_hv_device(info->device);
 383         struct synthvid_msg msg;
 384
 385         memset(&msg, 0, sizeof(struct synthvid_msg));
 386         if (x2 == INT_MAX)
 387                 x2 = info->var.xres;
 388         if (y2 == INT_MAX)
 389                 y2 = info->var.yres;
 390
 391         msg.vid_hdr.type = SYNTHVID_DIRT;
 392         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 393                 sizeof(struct synthvid_dirt);
 394         msg.dirt.video_output = 0;
 395         msg.dirt.dirt_count = 1;
 396         msg.dirt.rect[0].x1 = (x1 > x2) ? 0 : x1;
 397         msg.dirt.rect[0].y1 = (y1 > y2) ? 0 : y1;
 398         msg.dirt.rect[0].x2 =
 399                 (x2 < x1 || x2 > info->var.xres) ? info->var.xres : x2;
 400         msg.dirt.rect[0].y2 =
 401                 (y2 < y1 || y2 > info->var.yres) ? info->var.yres : y2;
 402
 403         synthvid_send(hdev, &msg);
 404
 405         return 0;
 406 }
 407
 408 static void hvfb_docopy(struct hvfb_par *par,
 409                         unsigned long offset,
 410                         unsigned long size)
 411 {
 412         if (!par || !par->mmio_vp || !par->dio_vp || !par->fb_ready ||
 413             size == 0 || offset >= dio_fb_size)
 414                 return;
 415
 416         if (offset + size > dio_fb_size)
 417                 size = dio_fb_size - offset;
 418
 419         memcpy(par->mmio_vp + offset, par->dio_vp + offset, size);
 420 }
 421
 422 /* Deferred IO callback */
 423 static void synthvid_deferred_io(struct fb_info *p,
 424                                  struct list_head *pagelist)
 425 {
 426         struct hvfb_par *par = p->par;
 427         struct page *page;
 428         unsigned long start, end;
 429         int y1, y2, miny, maxy;
 430
 431         miny = INT_MAX;
 432         maxy = 0;
 433
 434         /*
 435          * Merge dirty pages. It is possible that last page cross
 436          * over the end of frame buffer row yres. This is taken care of
 437          * in synthvid_update function by clamping the y2
 438          * value to yres.
 439          */
 440         list_for_each_entry(page, pagelist, lru) {
 441                 start = page->index << PAGE_SHIFT;
 442                 end = start + PAGE_SIZE - 1;
 443                 y1 = start / p->fix.line_length;
 444                 y2 = end / p->fix.line_length;
 445                 miny = min_t(int, miny, y1);
 446                 maxy = max_t(int, maxy, y2);
 447
 448                 /* Copy from dio space to mmio address */
 449                 if (par->fb_ready && par->need_docopy)
 450                         hvfb_docopy(par, start, PAGE_SIZE);
 451         }
 452
 453         if (par->fb_ready && par->update)
 454                 synthvid_update(p, 0, miny, p->var.xres, maxy + 1);
 455 }
 456
 457 static struct fb_deferred_io synthvid_defio = {
 458         .delay          = HZ / 20,
 459         .deferred_io    = synthvid_deferred_io,
 460 };
 461
 462 /*
 463  * Actions on received messages from host:
 464  * Complete the wait event.
 465  * Or, reply with screen and cursor info.
 466  */
 467 static void synthvid_recv_sub(struct hv_device *hdev)
 468 {
 469         struct fb_info *info = hv_get_drvdata(hdev);
 470         struct hvfb_par *par;
 471         struct synthvid_msg *msg;
 472
 473         if (!info)
 474                 return;
 475
 476         par = info->par;
 477         msg = (struct synthvid_msg *)par->recv_buf;
 478
 479         /* Complete the wait event */
 480         if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
 481             msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE ||
 482             msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
 483                 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
 484                 complete(&par->wait);
 485                 return;
 486         }
 487
 488         /* Reply with screen and cursor info */
 489         if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
 490                 if (par->fb_ready) {
 491                         synthvid_send_ptr(hdev);
 492                         synthvid_send_situ(hdev);
 493                 }
 494
 495                 par->update = msg->feature_chg.is_dirt_needed;
 496                 if (par->update)
 497                         schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
 498         }
 499 }
 500
 501 /* Receive callback for messages from the host */
 502 static void synthvid_receive(void *ctx)
 503 {
 504         struct hv_device *hdev = ctx;
 505         struct fb_info *info = hv_get_drvdata(hdev);
 506         struct hvfb_par *par;
 507         struct synthvid_msg *recv_buf;
 508         u32 bytes_recvd;
 509         u64 req_id;
 510         int ret;
 511
 512         if (!info)
 513                 return;
 514
 515         par = info->par;
 516         recv_buf = (struct synthvid_msg *)par->recv_buf;
 517
 518         do {
 519                 ret = vmbus_recvpacket(hdev->channel, recv_buf,
 520                                        MAX_VMBUS_PKT_SIZE,
 521                                        &bytes_recvd, &req_id);
 522                 if (bytes_recvd > 0 &&
 523                     recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
 524                         synthvid_recv_sub(hdev);
 525         } while (bytes_recvd > 0 && ret == 0);
 526 }
 527
 528 /* Check if the ver1 version is equal or greater than ver2 */
 529 static inline bool synthvid_ver_ge(u32 ver1, u32 ver2)
 530 {
 531         if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) ||
 532             (SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) &&
 533              SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2)))
 534                 return true;
 535
 536         return false;
 537 }
 538
 539 /* Check synthetic video protocol version with the host */
 540 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
 541 {
 542         struct fb_info *info = hv_get_drvdata(hdev);
 543         struct hvfb_par *par = info->par;
 544         struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
 545         int ret = 0;
 546         unsigned long t;
 547
 548         memset(msg, 0, sizeof(struct synthvid_msg));
 549         msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
 550         msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 551                 sizeof(struct synthvid_version_req);
 552         msg->ver_req.version = ver;
 553         synthvid_send(hdev, msg);
 554
 555         t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
 556         if (!t) {
 557                 pr_err("Time out on waiting version response\n");
 558                 ret = -ETIMEDOUT;
 559                 goto out;
 560         }
 561         if (!msg->ver_resp.is_accepted) {
 562                 ret = -ENODEV;
 563                 goto out;
 564         }
 565
 566         par->synthvid_version = ver;
 567         pr_info("Synthvid Version major %d, minor %d\n",
 568                 SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver));
 569
 570 out:
 571         return ret;
 572 }
 573
 574 /* Get current resolution from the host */
 575 static int synthvid_get_supported_resolution(struct hv_device *hdev)
 576 {
 577         struct fb_info *info = hv_get_drvdata(hdev);
 578         struct hvfb_par *par = info->par;
 579         struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
 580         int ret = 0;
 581         unsigned long t;
 582         u8 index;
 583         int i;
 584
 585         memset(msg, 0, sizeof(struct synthvid_msg));
 586         msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST;
 587         msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 588                 sizeof(struct synthvid_supported_resolution_req);
 589
 590         msg->resolution_req.maximum_resolution_count =
 591                 SYNTHVID_MAX_RESOLUTION_COUNT;
 592         synthvid_send(hdev, msg);
 593
 594         t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
 595         if (!t) {
 596                 pr_err("Time out on waiting resolution response\n");
 597                 ret = -ETIMEDOUT;
 598                 goto out;
 599         }
 600
 601         if (msg->resolution_resp.resolution_count == 0) {
 602                 pr_err("No supported resolutions\n");
 603                 ret = -ENODEV;
 604                 goto out;
 605         }
 606
 607         index = msg->resolution_resp.default_resolution_index;
 608         if (index >= msg->resolution_resp.resolution_count) {
 609                 pr_err("Invalid resolution index: %d\n", index);
 610                 ret = -ENODEV;
 611                 goto out;
 612         }
 613
 614         for (i = 0; i < msg->resolution_resp.resolution_count; i++) {
 615                 screen_width_max = max_t(unsigned int, screen_width_max,
 616                     msg->resolution_resp.supported_resolution[i].width);
 617                 screen_height_max = max_t(unsigned int, screen_height_max,
 618                     msg->resolution_resp.supported_resolution[i].height);
 619         }
 620
 621         screen_width =
 622                 msg->resolution_resp.supported_resolution[index].width;
 623         screen_height =
 624                 msg->resolution_resp.supported_resolution[index].height;
 625
 626 out:
 627         return ret;
 628 }
 629
 630 /* Connect to VSP (Virtual Service Provider) on host */
 631 static int synthvid_connect_vsp(struct hv_device *hdev)
 632 {
 633         struct fb_info *info = hv_get_drvdata(hdev);
 634         struct hvfb_par *par = info->par;
 635         int ret;
 636
 637         ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
 638                          NULL, 0, synthvid_receive, hdev);
 639         if (ret) {
 640                 pr_err("Unable to open vmbus channel\n");
 641                 return ret;
 642         }
 643
 644         /* Negotiate the protocol version with host */
 645         switch (vmbus_proto_version) {
 646         case VERSION_WIN10:
 647         case VERSION_WIN10_V5:
 648                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
 649                 if (!ret)
 650                         break;
 651                 fallthrough;
 652         case VERSION_WIN8:
 653         case VERSION_WIN8_1:
 654                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
 655                 if (!ret)
 656                         break;
 657                 fallthrough;
 658         case VERSION_WS2008:
 659         case VERSION_WIN7:
 660                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN7);
 661                 break;
 662         default:
 663                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
 664                 break;
 665         }
 666
 667         if (ret) {
 668                 pr_err("Synthetic video device version not accepted\n");
 669                 goto error;
 670         }
 671
 672         if (par->synthvid_version == SYNTHVID_VERSION_WIN7)
 673                 screen_depth = SYNTHVID_DEPTH_WIN7;
 674         else
 675                 screen_depth = SYNTHVID_DEPTH_WIN8;
 676
 677         if (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10)) {
 678                 ret = synthvid_get_supported_resolution(hdev);
 679                 if (ret)
 680                         pr_info("Failed to get supported resolution from host, use default\n");
 681         }
 682
 683         screen_fb_size = hdev->channel->offermsg.offer.
 684                                 mmio_megabytes * 1024 * 1024;
 685
 686         return 0;
 687
 688 error:
 689         vmbus_close(hdev->channel);
 690         return ret;
 691 }
 692
 693 /* Send VRAM and Situation messages to the host */
 694 static int synthvid_send_config(struct hv_device *hdev)
 695 {
 696         struct fb_info *info = hv_get_drvdata(hdev);
 697         struct hvfb_par *par = info->par;
 698         struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
 699         int ret = 0;
 700         unsigned long t;
 701
 702         /* Send VRAM location */
 703         memset(msg, 0, sizeof(struct synthvid_msg));
 704         msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
 705         msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 706                 sizeof(struct synthvid_vram_location);
 707         msg->vram.user_ctx = msg->vram.vram_gpa = par->mmio_pp;
 708         msg->vram.is_vram_gpa_specified = 1;
 709         synthvid_send(hdev, msg);
 710
 711         t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
 712         if (!t) {
 713                 pr_err("Time out on waiting vram location ack\n");
 714                 ret = -ETIMEDOUT;
 715                 goto out;
 716         }
 717         if (msg->vram_ack.user_ctx != par->mmio_pp) {
 718                 pr_err("Unable to set VRAM location\n");
 719                 ret = -ENODEV;
 720                 goto out;
 721         }
 722
 723         /* Send pointer and situation update */
 724         synthvid_send_ptr(hdev);
 725         synthvid_send_situ(hdev);
 726
 727 out:
 728         return ret;
 729 }
 730
 731
 732 /*
 733  * Delayed work callback:
 734  * It is scheduled to call whenever update request is received and it has
 735  * not been called in last HVFB_ONDEMAND_THROTTLE time interval.
 736  */
 737 static void hvfb_update_work(struct work_struct *w)
 738 {
 739         struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
 740         struct fb_info *info = par->info;
 741         unsigned long flags;
 742         int x1, x2, y1, y2;
 743         int j;
 744
 745         spin_lock_irqsave(&par->delayed_refresh_lock, flags);
 746         /* Reset the request flag */
 747         par->delayed_refresh = false;
 748
 749         /* Store the dirty rectangle to local variables */
 750         x1 = par->x1;
 751         x2 = par->x2;
 752         y1 = par->y1;
 753         y2 = par->y2;
 754
 755         /* Clear dirty rectangle */
 756         par->x1 = par->y1 = INT_MAX;
 757         par->x2 = par->y2 = 0;
 758
 759         spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
 760
 761         if (x1 > info->var.xres || x2 > info->var.xres ||
 762             y1 > info->var.yres || y2 > info->var.yres || x2 <= x1)
 763                 return;
 764
 765         /* Copy the dirty rectangle to frame buffer memory */
 766         if (par->need_docopy)
 767                 for (j = y1; j < y2; j++)
 768                         hvfb_docopy(par,
 769                                     j * info->fix.line_length +
 770                                     (x1 * screen_depth / 8),
 771                                     (x2 - x1) * screen_depth / 8);
 772
 773         /* Refresh */
 774         if (par->fb_ready && par->update)
 775                 synthvid_update(info, x1, y1, x2, y2);
 776 }
 777
 778 /*
 779  * Control the on-demand refresh frequency. It schedules a delayed
 780  * screen update if it has not yet.
 781  */
 782 static void hvfb_ondemand_refresh_throttle(struct hvfb_par *par,
 783                                            int x1, int y1, int w, int h)
 784 {
 785         unsigned long flags;
 786         int x2 = x1 + w;
 787         int y2 = y1 + h;
 788
 789         spin_lock_irqsave(&par->delayed_refresh_lock, flags);
 790
 791         /* Merge dirty rectangle */
 792         par->x1 = min_t(int, par->x1, x1);
 793         par->y1 = min_t(int, par->y1, y1);
 794         par->x2 = max_t(int, par->x2, x2);
 795         par->y2 = max_t(int, par->y2, y2);
 796
 797         /* Schedule a delayed screen update if not yet */
 798         if (par->delayed_refresh == false) {
 799                 schedule_delayed_work(&par->dwork,
 800                                       HVFB_ONDEMAND_THROTTLE);
 801                 par->delayed_refresh = true;
 802         }
 803
 804         spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
 805 }
 806
 807 static int hvfb_on_panic(struct notifier_block *nb,
 808                          unsigned long e, void *p)
 809 {
 810         struct hvfb_par *par;
 811         struct fb_info *info;
 812
 813         par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
 814         par->synchronous_fb = true;
 815         info = par->info;
 816         if (par->need_docopy)
 817                 hvfb_docopy(par, 0, dio_fb_size);
 818         synthvid_update(info, 0, 0, INT_MAX, INT_MAX);
 819
 820         return NOTIFY_DONE;
 821 }
 822
 823 /* Framebuffer operation handlers */
 824
 825 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 826 {
 827         if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
 828             var->xres > screen_width || var->yres >  screen_height ||
 829             var->bits_per_pixel != screen_depth)
 830                 return -EINVAL;
 831
 832         var->xres_virtual = var->xres;
 833         var->yres_virtual = var->yres;
 834
 835         return 0;
 836 }
 837
 838 static int hvfb_set_par(struct fb_info *info)
 839 {
 840         struct hv_device *hdev = device_to_hv_device(info->device);
 841
 842         return synthvid_send_situ(hdev);
 843 }
 844
 845
 846 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
 847 {
 848         return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
 849 }
 850
 851 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
 852                           unsigned blue, unsigned transp, struct fb_info *info)
 853 {
 854         u32 *pal = info->pseudo_palette;
 855
 856         if (regno > 15)
 857                 return -EINVAL;
 858
 859         pal[regno] = chan_to_field(red, &info->var.red)
 860                 | chan_to_field(green, &info->var.green)
 861                 | chan_to_field(blue, &info->var.blue)
 862                 | chan_to_field(transp, &info->var.transp);
 863
 864         return 0;
 865 }
 866
 867 static int hvfb_blank(int blank, struct fb_info *info)
 868 {
 869         return 1;       /* get fb_blank to set the colormap to all black */
 870 }
 871
 872 static void hvfb_cfb_fillrect(struct fb_info *p,
 873                               const struct fb_fillrect *rect)
 874 {
 875         struct hvfb_par *par = p->par;
 876
 877         cfb_fillrect(p, rect);
 878         if (par->synchronous_fb)
 879                 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
 880         else
 881                 hvfb_ondemand_refresh_throttle(par, rect->dx, rect->dy,
 882                                                rect->width, rect->height);
 883 }
 884
 885 static void hvfb_cfb_copyarea(struct fb_info *p,
 886                               const struct fb_copyarea *area)
 887 {
 888         struct hvfb_par *par = p->par;
 889
 890         cfb_copyarea(p, area);
 891         if (par->synchronous_fb)
 892                 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
 893         else
 894                 hvfb_ondemand_refresh_throttle(par, area->dx, area->dy,
 895                                                area->width, area->height);
 896 }
 897
 898 static void hvfb_cfb_imageblit(struct fb_info *p,
 899                                const struct fb_image *image)
 900 {
 901         struct hvfb_par *par = p->par;
 902
 903         cfb_imageblit(p, image);
 904         if (par->synchronous_fb)
 905                 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
 906         else
 907                 hvfb_ondemand_refresh_throttle(par, image->dx, image->dy,
 908                                                image->width, image->height);
 909 }
 910
 911 static const struct fb_ops hvfb_ops = {
 912         .owner = THIS_MODULE,
 913         .fb_check_var = hvfb_check_var,
 914         .fb_set_par = hvfb_set_par,
 915         .fb_setcolreg = hvfb_setcolreg,
 916         .fb_fillrect = hvfb_cfb_fillrect,
 917         .fb_copyarea = hvfb_cfb_copyarea,
 918         .fb_imageblit = hvfb_cfb_imageblit,
 919         .fb_blank = hvfb_blank,
 920 };
 921
 922
 923 /* Get options from kernel paramenter "video=" */
 924 static void hvfb_get_option(struct fb_info *info)
 925 {
 926         struct hvfb_par *par = info->par;
 927         char *opt = NULL, *p;
 928         uint x = 0, y = 0;
 929
 930         if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
 931                 return;
 932
 933         p = strsep(&opt, "x");
 934         if (!*p || kstrtouint(p, 0, &x) ||
 935             !opt || !*opt || kstrtouint(opt, 0, &y)) {
 936                 pr_err("Screen option is invalid: skipped\n");
 937                 return;
 938         }
 939
 940         if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
 941             (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10) &&
 942             (x > screen_width_max || y > screen_height_max)) ||
 943             (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
 944              x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8) ||
 945             (par->synthvid_version == SYNTHVID_VERSION_WIN7 &&
 946              (x > SYNTHVID_WIDTH_MAX_WIN7 || y > SYNTHVID_HEIGHT_MAX_WIN7))) {
 947                 pr_err("Screen resolution option is out of range: skipped\n");
 948                 return;
 949         }
 950
 951         screen_width = x;
 952         screen_height = y;
 953         return;
 954 }
 955
 956 /*
 957  * Allocate enough contiguous physical memory.
 958  * Return physical address if succeeded or -1 if failed.
 959  */
 960 static phys_addr_t hvfb_get_phymem(struct hv_device *hdev,
 961                                    unsigned int request_size)
 962 {
 963         struct page *page = NULL;
 964         dma_addr_t dma_handle;
 965         void *vmem;
 966         phys_addr_t paddr = 0;
 967         unsigned int order = get_order(request_size);
 968
 969         if (request_size == 0)
 970                 return -1;
 971
 972         if (order < MAX_ORDER) {
 973                 /* Call alloc_pages if the size is less than 2^MAX_ORDER */
 974                 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
 975                 if (!page)
 976                         return -1;
 977
 978                 paddr = (page_to_pfn(page) << PAGE_SHIFT);
 979         } else {
 980                 /* Allocate from CMA */
 981                 hdev->device.coherent_dma_mask = DMA_BIT_MASK(64);
 982
 983                 vmem = dma_alloc_coherent(&hdev->device,
 984                                           round_up(request_size, PAGE_SIZE),
 985                                           &dma_handle,
 986                                           GFP_KERNEL | __GFP_NOWARN);
 987
 988                 if (!vmem)
 989                         return -1;
 990
 991                 paddr = virt_to_phys(vmem);
 992         }
 993
 994         return paddr;
 995 }
 996
 997 /* Release contiguous physical memory */
 998 static void hvfb_release_phymem(struct hv_device *hdev,
 999                                 phys_addr_t paddr, unsigned int size)
1000 {
1001         unsigned int order = get_order(size);
1002
1003         if (order < MAX_ORDER)
1004                 __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order);
1005         else
1006                 dma_free_coherent(&hdev->device,
1007                                   round_up(size, PAGE_SIZE),
1008                                   phys_to_virt(paddr),
1009                                   paddr);
1010 }
1011
1012
1013 /* Get framebuffer memory from Hyper-V video pci space */
1014 static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
1015 {
1016         struct hvfb_par *par = info->par;
1017         struct pci_dev *pdev  = NULL;
1018         void __iomem *fb_virt;
1019         int gen2vm = efi_enabled(EFI_BOOT);
1020         resource_size_t pot_start, pot_end;
1021         phys_addr_t paddr;
1022         int ret;
1023
1024         info->apertures = alloc_apertures(1);
1025         if (!info->apertures)
1026                 return -ENOMEM;
1027
1028         if (!gen2vm) {
1029                 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
1030                         PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
1031                 if (!pdev) {
1032                         pr_err("Unable to find PCI Hyper-V video\n");
1033                         kfree(info->apertures);
1034                         return -ENODEV;
1035                 }
1036
1037                 info->apertures->ranges[0].base = pci_resource_start(pdev, 0);
1038                 info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
1039
1040                 /*
1041                  * For Gen 1 VM, we can directly use the contiguous memory
1042                  * from VM. If we succeed, deferred IO happens directly
1043                  * on this allocated framebuffer memory, avoiding extra
1044                  * memory copy.
1045                  */
1046                 paddr = hvfb_get_phymem(hdev, screen_fb_size);
1047                 if (paddr != (phys_addr_t) -1) {
1048                         par->mmio_pp = paddr;
1049                         par->mmio_vp = par->dio_vp = __va(paddr);
1050
1051                         info->fix.smem_start = paddr;
1052                         info->fix.smem_len = screen_fb_size;
1053                         info->screen_base = par->mmio_vp;
1054                         info->screen_size = screen_fb_size;
1055
1056                         par->need_docopy = false;
1057                         goto getmem_done;
1058                 }
1059                 pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n");
1060         } else {
1061                 info->apertures->ranges[0].base = screen_info.lfb_base;
1062                 info->apertures->ranges[0].size = screen_info.lfb_size;
1063         }
1064
1065         /*
1066          * Cannot use the contiguous physical memory.
1067          * Allocate mmio space for framebuffer.
1068          */
1069         dio_fb_size =
1070                 screen_width * screen_height * screen_depth / 8;
1071
1072         if (gen2vm) {
1073                 pot_start = 0;
1074                 pot_end = -1;
1075         } else {
1076                 if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
1077                     pci_resource_len(pdev, 0) < screen_fb_size) {
1078                         pr_err("Resource not available or (0x%lx < 0x%lx)\n",
1079                                (unsigned long) pci_resource_len(pdev, 0),
1080                                (unsigned long) screen_fb_size);
1081                         goto err1;
1082                 }
1083
1084                 pot_end = pci_resource_end(pdev, 0);
1085                 pot_start = pot_end - screen_fb_size + 1;
1086         }
1087
1088         ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
1089                                   screen_fb_size, 0x100000, true);
1090         if (ret != 0) {
1091                 pr_err("Unable to allocate framebuffer memory\n");
1092                 goto err1;
1093         }
1094
1095         fb_virt = ioremap(par->mem->start, screen_fb_size);
1096         if (!fb_virt)
1097                 goto err2;
1098
1099         /* Allocate memory for deferred IO */
1100         par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE));
1101         if (par->dio_vp == NULL)
1102                 goto err3;
1103
1104         /* Physical address of FB device */
1105         par->mmio_pp = par->mem->start;
1106         /* Virtual address of FB device */
1107         par->mmio_vp = (unsigned char *) fb_virt;
1108
1109         info->fix.smem_start = par->mem->start;
1110         info->fix.smem_len = dio_fb_size;
1111         info->screen_base = par->dio_vp;
1112         info->screen_size = dio_fb_size;
1113
1114 getmem_done:
1115         remove_conflicting_framebuffers(info->apertures,
1116                                         KBUILD_MODNAME, false);
1117
1118         if (gen2vm) {
1119                 /* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */
1120                 screen_info.lfb_size = 0;
1121                 screen_info.lfb_base = 0;
1122                 screen_info.orig_video_isVGA = 0;
1123         } else {
1124                 pci_dev_put(pdev);
1125         }
1126         kfree(info->apertures);
1127
1128         return 0;
1129
1130 err3:
1131         iounmap(fb_virt);
1132 err2:
1133         vmbus_free_mmio(par->mem->start, screen_fb_size);
1134         par->mem = NULL;
1135 err1:
1136         if (!gen2vm)
1137                 pci_dev_put(pdev);
1138         kfree(info->apertures);
1139
1140         return -ENOMEM;
1141 }
1142
1143 /* Release the framebuffer */
1144 static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info)
1145 {
1146         struct hvfb_par *par = info->par;
1147
1148         if (par->need_docopy) {
1149                 vfree(par->dio_vp);
1150                 iounmap(info->screen_base);
1151                 vmbus_free_mmio(par->mem->start, screen_fb_size);
1152         } else {
1153                 hvfb_release_phymem(hdev, info->fix.smem_start,
1154                                     screen_fb_size);
1155         }
1156
1157         par->mem = NULL;
1158 }
1159
1160
1161 static int hvfb_probe(struct hv_device *hdev,
1162                       const struct hv_vmbus_device_id *dev_id)
1163 {
1164         struct fb_info *info;
1165         struct hvfb_par *par;
1166         int ret;
1167
1168         info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
1169         if (!info)
1170                 return -ENOMEM;
1171
1172         par = info->par;
1173         par->info = info;
1174         par->fb_ready = false;
1175         par->need_docopy = true;
1176         init_completion(&par->wait);
1177         INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
1178
1179         par->delayed_refresh = false;
1180         spin_lock_init(&par->delayed_refresh_lock);
1181         par->x1 = par->y1 = INT_MAX;
1182         par->x2 = par->y2 = 0;
1183
1184         /* Connect to VSP */
1185         hv_set_drvdata(hdev, info);
1186         ret = synthvid_connect_vsp(hdev);
1187         if (ret) {
1188                 pr_err("Unable to connect to VSP\n");
1189                 goto error1;
1190         }
1191
1192         hvfb_get_option(info);
1193         pr_info("Screen resolution: %dx%d, Color depth: %d\n",
1194                 screen_width, screen_height, screen_depth);
1195
1196         ret = hvfb_getmem(hdev, info);
1197         if (ret) {
1198                 pr_err("No memory for framebuffer\n");
1199                 goto error2;
1200         }
1201
1202         /* Set up fb_info */
1203         info->flags = FBINFO_DEFAULT;
1204
1205         info->var.xres_virtual = info->var.xres = screen_width;
1206         info->var.yres_virtual = info->var.yres = screen_height;
1207         info->var.bits_per_pixel = screen_depth;
1208
1209         if (info->var.bits_per_pixel == 16) {
1210                 info->var.red = (struct fb_bitfield){11, 5, 0};
1211                 info->var.green = (struct fb_bitfield){5, 6, 0};
1212                 info->var.blue = (struct fb_bitfield){0, 5, 0};
1213                 info->var.transp = (struct fb_bitfield){0, 0, 0};
1214         } else {
1215                 info->var.red = (struct fb_bitfield){16, 8, 0};
1216                 info->var.green = (struct fb_bitfield){8, 8, 0};
1217                 info->var.blue = (struct fb_bitfield){0, 8, 0};
1218                 info->var.transp = (struct fb_bitfield){24, 8, 0};
1219         }
1220
1221         info->var.activate = FB_ACTIVATE_NOW;
1222         info->var.height = -1;
1223         info->var.width = -1;
1224         info->var.vmode = FB_VMODE_NONINTERLACED;
1225
1226         strcpy(info->fix.id, KBUILD_MODNAME);
1227         info->fix.type = FB_TYPE_PACKED_PIXELS;
1228         info->fix.visual = FB_VISUAL_TRUECOLOR;
1229         info->fix.line_length = screen_width * screen_depth / 8;
1230         info->fix.accel = FB_ACCEL_NONE;
1231
1232         info->fbops = &hvfb_ops;
1233         info->pseudo_palette = par->pseudo_palette;
1234
1235         /* Initialize deferred IO */
1236         info->fbdefio = &synthvid_defio;
1237         fb_deferred_io_init(info);
1238
1239         /* Send config to host */
1240         ret = synthvid_send_config(hdev);
1241         if (ret)
1242                 goto error;
1243
1244         ret = register_framebuffer(info);
1245         if (ret) {
1246                 pr_err("Unable to register framebuffer\n");
1247                 goto error;
1248         }
1249
1250         par->fb_ready = true;
1251
1252         par->synchronous_fb = false;
1253         par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
1254         atomic_notifier_chain_register(&panic_notifier_list,
1255                                        &par->hvfb_panic_nb);
1256
1257         return 0;
1258
1259 error:
1260         fb_deferred_io_cleanup(info);
1261         hvfb_putmem(hdev, info);
1262 error2:
1263         vmbus_close(hdev->channel);
1264 error1:
1265         cancel_delayed_work_sync(&par->dwork);
1266         hv_set_drvdata(hdev, NULL);
1267         framebuffer_release(info);
1268         return ret;
1269 }
1270
1271
1272 static int hvfb_remove(struct hv_device *hdev)
1273 {
1274         struct fb_info *info = hv_get_drvdata(hdev);
1275         struct hvfb_par *par = info->par;
1276
1277         atomic_notifier_chain_unregister(&panic_notifier_list,
1278                                          &par->hvfb_panic_nb);
1279
1280         par->update = false;
1281         par->fb_ready = false;
1282
1283         fb_deferred_io_cleanup(info);
1284
1285         unregister_framebuffer(info);
1286         cancel_delayed_work_sync(&par->dwork);
1287
1288         vmbus_close(hdev->channel);
1289         hv_set_drvdata(hdev, NULL);
1290
1291         hvfb_putmem(hdev, info);
1292         framebuffer_release(info);
1293
1294         return 0;
1295 }
1296
1297 static int hvfb_suspend(struct hv_device *hdev)
1298 {
1299         struct fb_info *info = hv_get_drvdata(hdev);
1300         struct hvfb_par *par = info->par;
1301
1302         console_lock();
1303
1304         /* 1 means do suspend */
1305         fb_set_suspend(info, 1);
1306
1307         cancel_delayed_work_sync(&par->dwork);
1308         cancel_delayed_work_sync(&info->deferred_work);
1309
1310         par->update_saved = par->update;
1311         par->update = false;
1312         par->fb_ready = false;
1313
1314         vmbus_close(hdev->channel);
1315
1316         console_unlock();
1317
1318         return 0;
1319 }
1320
1321 static int hvfb_resume(struct hv_device *hdev)
1322 {
1323         struct fb_info *info = hv_get_drvdata(hdev);
1324         struct hvfb_par *par = info->par;
1325         int ret;
1326
1327         console_lock();
1328
1329         ret = synthvid_connect_vsp(hdev);
1330         if (ret != 0)
1331                 goto out;
1332
1333         ret = synthvid_send_config(hdev);
1334         if (ret != 0) {
1335                 vmbus_close(hdev->channel);
1336                 goto out;
1337         }
1338
1339         par->fb_ready = true;
1340         par->update = par->update_saved;
1341
1342         schedule_delayed_work(&info->deferred_work, info->fbdefio->delay);
1343         schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
1344
1345         /* 0 means do resume */
1346         fb_set_suspend(info, 0);
1347
1348 out:
1349         console_unlock();
1350
1351         return ret;
1352 }
1353
1354
1355 static const struct pci_device_id pci_stub_id_table[] = {
1356         {
1357                 .vendor      = PCI_VENDOR_ID_MICROSOFT,
1358                 .device      = PCI_DEVICE_ID_HYPERV_VIDEO,
1359         },
1360         { /* end of list */ }
1361 };
1362
1363 static const struct hv_vmbus_device_id id_table[] = {
1364         /* Synthetic Video Device GUID */
1365         {HV_SYNTHVID_GUID},
1366         {}
1367 };
1368
1369 MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
1370 MODULE_DEVICE_TABLE(vmbus, id_table);
1371
1372 static struct hv_driver hvfb_drv = {
1373         .name = KBUILD_MODNAME,
1374         .id_table = id_table,
1375         .probe = hvfb_probe,
1376         .remove = hvfb_remove,
1377         .suspend = hvfb_suspend,
1378         .resume = hvfb_resume,
1379         .driver = {
1380                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1381         },
1382 };
1383
1384 static int hvfb_pci_stub_probe(struct pci_dev *pdev,
1385                                const struct pci_device_id *ent)
1386 {
1387         return 0;
1388 }
1389
1390 static void hvfb_pci_stub_remove(struct pci_dev *pdev)
1391 {
1392 }
1393
1394 static struct pci_driver hvfb_pci_stub_driver = {
1395         .name =         KBUILD_MODNAME,
1396         .id_table =     pci_stub_id_table,
1397         .probe =        hvfb_pci_stub_probe,
1398         .remove =       hvfb_pci_stub_remove,
1399         .driver = {
1400                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1401         }
1402 };
1403
1404 static int __init hvfb_drv_init(void)
1405 {
1406         int ret;
1407
1408         ret = vmbus_driver_register(&hvfb_drv);
1409         if (ret != 0)
1410                 return ret;
1411
1412         ret = pci_register_driver(&hvfb_pci_stub_driver);
1413         if (ret != 0) {
1414                 vmbus_driver_unregister(&hvfb_drv);
1415                 return ret;
1416         }
1417
1418         return 0;
1419 }
1420
1421 static void __exit hvfb_drv_exit(void)
1422 {
1423         pci_unregister_driver(&hvfb_pci_stub_driver);
1424         vmbus_driver_unregister(&hvfb_drv);
1425 }
1426
1427 module_init(hvfb_drv_init);
1428 module_exit(hvfb_drv_exit);
1429
1430 MODULE_LICENSE("GPL");
1431 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");