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 <[email protected]>
   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
  28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  29
  30 #include <linux/module.h>
  31 #include <linux/kernel.h>
  32 #include <linux/init.h>
  33 #include <linux/completion.h>
  34 #include <linux/fb.h>
  35 #include <linux/pci.h>
  36 #include <linux/efi.h>
  37
  38 #include <linux/hyperv.h>
  39
  40
  41 /* Hyper-V Synthetic Video Protocol definitions and structures */
  42 #define MAX_VMBUS_PKT_SIZE 0x4000
  43
  44 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
  45 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
  46 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
  47
  48 #define SYNTHVID_DEPTH_WIN7 16
  49 #define SYNTHVID_DEPTH_WIN8 32
  50
  51 #define SYNTHVID_FB_SIZE_WIN7 (4 * 1024 * 1024)
  52 #define SYNTHVID_WIDTH_MAX_WIN7 1600
  53 #define SYNTHVID_HEIGHT_MAX_WIN7 1200
  54
  55 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
  56
  57 #define PCI_VENDOR_ID_MICROSOFT 0x1414
  58 #define PCI_DEVICE_ID_HYPERV_VIDEO 0x5353
  59
  60
  61 enum pipe_msg_type {
  62         PIPE_MSG_INVALID,
  63         PIPE_MSG_DATA,
  64         PIPE_MSG_MAX
  65 };
  66
  67 struct pipe_msg_hdr {
  68         u32 type;
  69         u32 size; /* size of message after this field */
  70 } __packed;
  71
  72
  73 enum synthvid_msg_type {
  74         SYNTHVID_ERROR                  = 0,
  75         SYNTHVID_VERSION_REQUEST        = 1,
  76         SYNTHVID_VERSION_RESPONSE       = 2,
  77         SYNTHVID_VRAM_LOCATION          = 3,
  78         SYNTHVID_VRAM_LOCATION_ACK      = 4,
  79         SYNTHVID_SITUATION_UPDATE       = 5,
  80         SYNTHVID_SITUATION_UPDATE_ACK   = 6,
  81         SYNTHVID_POINTER_POSITION       = 7,
  82         SYNTHVID_POINTER_SHAPE          = 8,
  83         SYNTHVID_FEATURE_CHANGE         = 9,
  84         SYNTHVID_DIRT                   = 10,
  85
  86         SYNTHVID_MAX                    = 11
  87 };
  88
  89 struct synthvid_msg_hdr {
  90         u32 type;
  91         u32 size;  /* size of this header + payload after this field*/
  92 } __packed;
  93
  94
  95 struct synthvid_version_req {
  96         u32 version;
  97 } __packed;
  98
  99 struct synthvid_version_resp {
 100         u32 version;
 101         u8 is_accepted;
 102         u8 max_video_outputs;
 103 } __packed;
 104
 105 struct synthvid_vram_location {
 106         u64 user_ctx;
 107         u8 is_vram_gpa_specified;
 108         u64 vram_gpa;
 109 } __packed;
 110
 111 struct synthvid_vram_location_ack {
 112         u64 user_ctx;
 113 } __packed;
 114
 115 struct video_output_situation {
 116         u8 active;
 117         u32 vram_offset;
 118         u8 depth_bits;
 119         u32 width_pixels;
 120         u32 height_pixels;
 121         u32 pitch_bytes;
 122 } __packed;
 123
 124 struct synthvid_situation_update {
 125         u64 user_ctx;
 126         u8 video_output_count;
 127         struct video_output_situation video_output[1];
 128 } __packed;
 129
 130 struct synthvid_situation_update_ack {
 131         u64 user_ctx;
 132 } __packed;
 133
 134 struct synthvid_pointer_position {
 135         u8 is_visible;
 136         u8 video_output;
 137         s32 image_x;
 138         s32 image_y;
 139 } __packed;
 140
 141
 142 #define CURSOR_MAX_X 96
 143 #define CURSOR_MAX_Y 96
 144 #define CURSOR_ARGB_PIXEL_SIZE 4
 145 #define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE)
 146 #define CURSOR_COMPLETE (-1)
 147
 148 struct synthvid_pointer_shape {
 149         u8 part_idx;
 150         u8 is_argb;
 151         u32 width; /* CURSOR_MAX_X at most */
 152         u32 height; /* CURSOR_MAX_Y at most */
 153         u32 hot_x; /* hotspot relative to upper-left of pointer image */
 154         u32 hot_y;
 155         u8 data[4];
 156 } __packed;
 157
 158 struct synthvid_feature_change {
 159         u8 is_dirt_needed;
 160         u8 is_ptr_pos_needed;
 161         u8 is_ptr_shape_needed;
 162         u8 is_situ_needed;
 163 } __packed;
 164
 165 struct rect {
 166         s32 x1, y1; /* top left corner */
 167         s32 x2, y2; /* bottom right corner, exclusive */
 168 } __packed;
 169
 170 struct synthvid_dirt {
 171         u8 video_output;
 172         u8 dirt_count;
 173         struct rect rect[1];
 174 } __packed;
 175
 176 struct synthvid_msg {
 177         struct pipe_msg_hdr pipe_hdr;
 178         struct synthvid_msg_hdr vid_hdr;
 179         union {
 180                 struct synthvid_version_req ver_req;
 181                 struct synthvid_version_resp ver_resp;
 182                 struct synthvid_vram_location vram;
 183                 struct synthvid_vram_location_ack vram_ack;
 184                 struct synthvid_situation_update situ;
 185                 struct synthvid_situation_update_ack situ_ack;
 186                 struct synthvid_pointer_position ptr_pos;
 187                 struct synthvid_pointer_shape ptr_shape;
 188                 struct synthvid_feature_change feature_chg;
 189                 struct synthvid_dirt dirt;
 190         };
 191 } __packed;
 192
 193
 194
 195 /* FB driver definitions and structures */
 196 #define HVFB_WIDTH 1152 /* default screen width */
 197 #define HVFB_HEIGHT 864 /* default screen height */
 198 #define HVFB_WIDTH_MIN 640
 199 #define HVFB_HEIGHT_MIN 480
 200
 201 #define RING_BUFSIZE (256 * 1024)
 202 #define VSP_TIMEOUT (10 * HZ)
 203 #define HVFB_UPDATE_DELAY (HZ / 20)
 204
 205 struct hvfb_par {
 206         struct fb_info *info;
 207         struct resource *mem;
 208         bool fb_ready; /* fb device is ready */
 209         struct completion wait;
 210         u32 synthvid_version;
 211
 212         struct delayed_work dwork;
 213         bool update;
 214
 215         u32 pseudo_palette[16];
 216         u8 init_buf[MAX_VMBUS_PKT_SIZE];
 217         u8 recv_buf[MAX_VMBUS_PKT_SIZE];
 218
 219         /* If true, the VSC notifies the VSP on every framebuffer change */
 220         bool synchronous_fb;
 221
 222         struct notifier_block hvfb_panic_nb;
 223 };
 224
 225 static uint screen_width = HVFB_WIDTH;
 226 static uint screen_height = HVFB_HEIGHT;
 227 static uint screen_depth;
 228 static uint screen_fb_size;
 229
 230 /* Send message to Hyper-V host */
 231 static inline int synthvid_send(struct hv_device *hdev,
 232                                 struct synthvid_msg *msg)
 233 {
 234         static atomic64_t request_id = ATOMIC64_INIT(0);
 235         int ret;
 236
 237         msg->pipe_hdr.type = PIPE_MSG_DATA;
 238         msg->pipe_hdr.size = msg->vid_hdr.size;
 239
 240         ret = vmbus_sendpacket(hdev->channel, msg,
 241                                msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
 242                                atomic64_inc_return(&request_id),
 243                                VM_PKT_DATA_INBAND, 0);
 244
 245         if (ret)
 246                 pr_err("Unable to send packet via vmbus\n");
 247
 248         return ret;
 249 }
 250
 251
 252 /* Send screen resolution info to host */
 253 static int synthvid_send_situ(struct hv_device *hdev)
 254 {
 255         struct fb_info *info = hv_get_drvdata(hdev);
 256         struct synthvid_msg msg;
 257
 258         if (!info)
 259                 return -ENODEV;
 260
 261         memset(&msg, 0, sizeof(struct synthvid_msg));
 262
 263         msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
 264         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 265                 sizeof(struct synthvid_situation_update);
 266         msg.situ.user_ctx = 0;
 267         msg.situ.video_output_count = 1;
 268         msg.situ.video_output[0].active = 1;
 269         msg.situ.video_output[0].vram_offset = 0;
 270         msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
 271         msg.situ.video_output[0].width_pixels = info->var.xres;
 272         msg.situ.video_output[0].height_pixels = info->var.yres;
 273         msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
 274
 275         synthvid_send(hdev, &msg);
 276
 277         return 0;
 278 }
 279
 280 /* Send mouse pointer info to host */
 281 static int synthvid_send_ptr(struct hv_device *hdev)
 282 {
 283         struct synthvid_msg msg;
 284
 285         memset(&msg, 0, sizeof(struct synthvid_msg));
 286         msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
 287         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 288                 sizeof(struct synthvid_pointer_position);
 289         msg.ptr_pos.is_visible = 1;
 290         msg.ptr_pos.video_output = 0;
 291         msg.ptr_pos.image_x = 0;
 292         msg.ptr_pos.image_y = 0;
 293         synthvid_send(hdev, &msg);
 294
 295         memset(&msg, 0, sizeof(struct synthvid_msg));
 296         msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
 297         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 298                 sizeof(struct synthvid_pointer_shape);
 299         msg.ptr_shape.part_idx = CURSOR_COMPLETE;
 300         msg.ptr_shape.is_argb = 1;
 301         msg.ptr_shape.width = 1;
 302         msg.ptr_shape.height = 1;
 303         msg.ptr_shape.hot_x = 0;
 304         msg.ptr_shape.hot_y = 0;
 305         msg.ptr_shape.data[0] = 0;
 306         msg.ptr_shape.data[1] = 1;
 307         msg.ptr_shape.data[2] = 1;
 308         msg.ptr_shape.data[3] = 1;
 309         synthvid_send(hdev, &msg);
 310
 311         return 0;
 312 }
 313
 314 /* Send updated screen area (dirty rectangle) location to host */
 315 static int synthvid_update(struct fb_info *info)
 316 {
 317         struct hv_device *hdev = device_to_hv_device(info->device);
 318         struct synthvid_msg msg;
 319
 320         memset(&msg, 0, sizeof(struct synthvid_msg));
 321
 322         msg.vid_hdr.type = SYNTHVID_DIRT;
 323         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 324                 sizeof(struct synthvid_dirt);
 325         msg.dirt.video_output = 0;
 326         msg.dirt.dirt_count = 1;
 327         msg.dirt.rect[0].x1 = 0;
 328         msg.dirt.rect[0].y1 = 0;
 329         msg.dirt.rect[0].x2 = info->var.xres;
 330         msg.dirt.rect[0].y2 = info->var.yres;
 331
 332         synthvid_send(hdev, &msg);
 333
 334         return 0;
 335 }
 336
 337
 338 /*
 339  * Actions on received messages from host:
 340  * Complete the wait event.
 341  * Or, reply with screen and cursor info.
 342  */
 343 static void synthvid_recv_sub(struct hv_device *hdev)
 344 {
 345         struct fb_info *info = hv_get_drvdata(hdev);
 346         struct hvfb_par *par;
 347         struct synthvid_msg *msg;
 348
 349         if (!info)
 350                 return;
 351
 352         par = info->par;
 353         msg = (struct synthvid_msg *)par->recv_buf;
 354
 355         /* Complete the wait event */
 356         if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
 357             msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
 358                 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
 359                 complete(&par->wait);
 360                 return;
 361         }
 362
 363         /* Reply with screen and cursor info */
 364         if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
 365                 if (par->fb_ready) {
 366                         synthvid_send_ptr(hdev);
 367                         synthvid_send_situ(hdev);
 368                 }
 369
 370                 par->update = msg->feature_chg.is_dirt_needed;
 371                 if (par->update)
 372                         schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
 373         }
 374 }
 375
 376 /* Receive callback for messages from the host */
 377 static void synthvid_receive(void *ctx)
 378 {
 379         struct hv_device *hdev = ctx;
 380         struct fb_info *info = hv_get_drvdata(hdev);
 381         struct hvfb_par *par;
 382         struct synthvid_msg *recv_buf;
 383         u32 bytes_recvd;
 384         u64 req_id;
 385         int ret;
 386
 387         if (!info)
 388                 return;
 389
 390         par = info->par;
 391         recv_buf = (struct synthvid_msg *)par->recv_buf;
 392
 393         do {
 394                 ret = vmbus_recvpacket(hdev->channel, recv_buf,
 395                                        MAX_VMBUS_PKT_SIZE,
 396                                        &bytes_recvd, &req_id);
 397                 if (bytes_recvd > 0 &&
 398                     recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
 399                         synthvid_recv_sub(hdev);
 400         } while (bytes_recvd > 0 && ret == 0);
 401 }
 402
 403 /* Check synthetic video protocol version with the host */
 404 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
 405 {
 406         struct fb_info *info = hv_get_drvdata(hdev);
 407         struct hvfb_par *par = info->par;
 408         struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
 409         int ret = 0;
 410         unsigned long t;
 411
 412         memset(msg, 0, sizeof(struct synthvid_msg));
 413         msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
 414         msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 415                 sizeof(struct synthvid_version_req);
 416         msg->ver_req.version = ver;
 417         synthvid_send(hdev, msg);
 418
 419         t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
 420         if (!t) {
 421                 pr_err("Time out on waiting version response\n");
 422                 ret = -ETIMEDOUT;
 423                 goto out;
 424         }
 425         if (!msg->ver_resp.is_accepted) {
 426                 ret = -ENODEV;
 427                 goto out;
 428         }
 429
 430         par->synthvid_version = ver;
 431
 432 out:
 433         return ret;
 434 }
 435
 436 /* Connect to VSP (Virtual Service Provider) on host */
 437 static int synthvid_connect_vsp(struct hv_device *hdev)
 438 {
 439         struct fb_info *info = hv_get_drvdata(hdev);
 440         struct hvfb_par *par = info->par;
 441         int ret;
 442
 443         ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
 444                          NULL, 0, synthvid_receive, hdev);
 445         if (ret) {
 446                 pr_err("Unable to open vmbus channel\n");
 447                 return ret;
 448         }
 449
 450         /* Negotiate the protocol version with host */
 451         if (vmbus_proto_version == VERSION_WS2008 ||
 452             vmbus_proto_version == VERSION_WIN7)
 453                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN7);
 454         else
 455                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
 456
 457         if (ret) {
 458                 pr_err("Synthetic video device version not accepted\n");
 459                 goto error;
 460         }
 461
 462         if (par->synthvid_version == SYNTHVID_VERSION_WIN7)
 463                 screen_depth = SYNTHVID_DEPTH_WIN7;
 464         else
 465                 screen_depth = SYNTHVID_DEPTH_WIN8;
 466
 467         screen_fb_size = hdev->channel->offermsg.offer.
 468                                 mmio_megabytes * 1024 * 1024;
 469
 470         return 0;
 471
 472 error:
 473         vmbus_close(hdev->channel);
 474         return ret;
 475 }
 476
 477 /* Send VRAM and Situation messages to the host */
 478 static int synthvid_send_config(struct hv_device *hdev)
 479 {
 480         struct fb_info *info = hv_get_drvdata(hdev);
 481         struct hvfb_par *par = info->par;
 482         struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
 483         int ret = 0;
 484         unsigned long t;
 485
 486         /* Send VRAM location */
 487         memset(msg, 0, sizeof(struct synthvid_msg));
 488         msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
 489         msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 490                 sizeof(struct synthvid_vram_location);
 491         msg->vram.user_ctx = msg->vram.vram_gpa = info->fix.smem_start;
 492         msg->vram.is_vram_gpa_specified = 1;
 493         synthvid_send(hdev, msg);
 494
 495         t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
 496         if (!t) {
 497                 pr_err("Time out on waiting vram location ack\n");
 498                 ret = -ETIMEDOUT;
 499                 goto out;
 500         }
 501         if (msg->vram_ack.user_ctx != info->fix.smem_start) {
 502                 pr_err("Unable to set VRAM location\n");
 503                 ret = -ENODEV;
 504                 goto out;
 505         }
 506
 507         /* Send pointer and situation update */
 508         synthvid_send_ptr(hdev);
 509         synthvid_send_situ(hdev);
 510
 511 out:
 512         return ret;
 513 }
 514
 515
 516 /*
 517  * Delayed work callback:
 518  * It is called at HVFB_UPDATE_DELAY or longer time interval to process
 519  * screen updates. It is re-scheduled if further update is necessary.
 520  */
 521 static void hvfb_update_work(struct work_struct *w)
 522 {
 523         struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
 524         struct fb_info *info = par->info;
 525
 526         if (par->fb_ready)
 527                 synthvid_update(info);
 528
 529         if (par->update)
 530                 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
 531 }
 532
 533 static int hvfb_on_panic(struct notifier_block *nb,
 534                          unsigned long e, void *p)
 535 {
 536         struct hvfb_par *par;
 537         struct fb_info *info;
 538
 539         par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
 540         par->synchronous_fb = true;
 541         info = par->info;
 542         synthvid_update(info);
 543
 544         return NOTIFY_DONE;
 545 }
 546
 547 /* Framebuffer operation handlers */
 548
 549 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 550 {
 551         if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
 552             var->xres > screen_width || var->yres >  screen_height ||
 553             var->bits_per_pixel != screen_depth)
 554                 return -EINVAL;
 555
 556         var->xres_virtual = var->xres;
 557         var->yres_virtual = var->yres;
 558
 559         return 0;
 560 }
 561
 562 static int hvfb_set_par(struct fb_info *info)
 563 {
 564         struct hv_device *hdev = device_to_hv_device(info->device);
 565
 566         return synthvid_send_situ(hdev);
 567 }
 568
 569
 570 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
 571 {
 572         return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
 573 }
 574
 575 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
 576                           unsigned blue, unsigned transp, struct fb_info *info)
 577 {
 578         u32 *pal = info->pseudo_palette;
 579
 580         if (regno > 15)
 581                 return -EINVAL;
 582
 583         pal[regno] = chan_to_field(red, &info->var.red)
 584                 | chan_to_field(green, &info->var.green)
 585                 | chan_to_field(blue, &info->var.blue)
 586                 | chan_to_field(transp, &info->var.transp);
 587
 588         return 0;
 589 }
 590
 591 static int hvfb_blank(int blank, struct fb_info *info)
 592 {
 593         return 1;       /* get fb_blank to set the colormap to all black */
 594 }
 595
 596 static void hvfb_cfb_fillrect(struct fb_info *p,
 597                               const struct fb_fillrect *rect)
 598 {
 599         struct hvfb_par *par = p->par;
 600
 601         cfb_fillrect(p, rect);
 602         if (par->synchronous_fb)
 603                 synthvid_update(p);
 604 }
 605
 606 static void hvfb_cfb_copyarea(struct fb_info *p,
 607                               const struct fb_copyarea *area)
 608 {
 609         struct hvfb_par *par = p->par;
 610
 611         cfb_copyarea(p, area);
 612         if (par->synchronous_fb)
 613                 synthvid_update(p);
 614 }
 615
 616 static void hvfb_cfb_imageblit(struct fb_info *p,
 617                                const struct fb_image *image)
 618 {
 619         struct hvfb_par *par = p->par;
 620
 621         cfb_imageblit(p, image);
 622         if (par->synchronous_fb)
 623                 synthvid_update(p);
 624 }
 625
 626 static struct fb_ops hvfb_ops = {
 627         .owner = THIS_MODULE,
 628         .fb_check_var = hvfb_check_var,
 629         .fb_set_par = hvfb_set_par,
 630         .fb_setcolreg = hvfb_setcolreg,
 631         .fb_fillrect = hvfb_cfb_fillrect,
 632         .fb_copyarea = hvfb_cfb_copyarea,
 633         .fb_imageblit = hvfb_cfb_imageblit,
 634         .fb_blank = hvfb_blank,
 635 };
 636
 637
 638 /* Get options from kernel paramenter "video=" */
 639 static void hvfb_get_option(struct fb_info *info)
 640 {
 641         struct hvfb_par *par = info->par;
 642         char *opt = NULL, *p;
 643         uint x = 0, y = 0;
 644
 645         if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
 646                 return;
 647
 648         p = strsep(&opt, "x");
 649         if (!*p || kstrtouint(p, 0, &x) ||
 650             !opt || !*opt || kstrtouint(opt, 0, &y)) {
 651                 pr_err("Screen option is invalid: skipped\n");
 652                 return;
 653         }
 654
 655         if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
 656             (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
 657              x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8) ||
 658             (par->synthvid_version == SYNTHVID_VERSION_WIN7 &&
 659              (x > SYNTHVID_WIDTH_MAX_WIN7 || y > SYNTHVID_HEIGHT_MAX_WIN7))) {
 660                 pr_err("Screen resolution option is out of range: skipped\n");
 661                 return;
 662         }
 663
 664         screen_width = x;
 665         screen_height = y;
 666         return;
 667 }
 668
 669
 670 /* Get framebuffer memory from Hyper-V video pci space */
 671 static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
 672 {
 673         struct hvfb_par *par = info->par;
 674         struct pci_dev *pdev  = NULL;
 675         void __iomem *fb_virt;
 676         int gen2vm = efi_enabled(EFI_BOOT);
 677         resource_size_t pot_start, pot_end;
 678         int ret;
 679
 680         if (gen2vm) {
 681                 pot_start = 0;
 682                 pot_end = -1;
 683         } else {
 684                 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
 685                               PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
 686                 if (!pdev) {
 687                         pr_err("Unable to find PCI Hyper-V video\n");
 688                         return -ENODEV;
 689                 }
 690
 691                 if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
 692                     pci_resource_len(pdev, 0) < screen_fb_size)
 693                         goto err1;
 694
 695                 pot_end = pci_resource_end(pdev, 0);
 696                 pot_start = pot_end - screen_fb_size + 1;
 697         }
 698
 699         ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
 700                                   screen_fb_size, 0x100000, true);
 701         if (ret != 0) {
 702                 pr_err("Unable to allocate framebuffer memory\n");
 703                 goto err1;
 704         }
 705
 706         fb_virt = ioremap(par->mem->start, screen_fb_size);
 707         if (!fb_virt)
 708                 goto err2;
 709
 710         info->apertures = alloc_apertures(1);
 711         if (!info->apertures)
 712                 goto err3;
 713
 714         if (gen2vm) {
 715                 info->apertures->ranges[0].base = screen_info.lfb_base;
 716                 info->apertures->ranges[0].size = screen_info.lfb_size;
 717                 remove_conflicting_framebuffers(info->apertures,
 718                                                 KBUILD_MODNAME, false);
 719         } else {
 720                 info->apertures->ranges[0].base = pci_resource_start(pdev, 0);
 721                 info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
 722         }
 723
 724         info->fix.smem_start = par->mem->start;
 725         info->fix.smem_len = screen_fb_size;
 726         info->screen_base = fb_virt;
 727         info->screen_size = screen_fb_size;
 728
 729         if (!gen2vm)
 730                 pci_dev_put(pdev);
 731
 732         return 0;
 733
 734 err3:
 735         iounmap(fb_virt);
 736 err2:
 737         vmbus_free_mmio(par->mem->start, screen_fb_size);
 738         par->mem = NULL;
 739 err1:
 740         if (!gen2vm)
 741                 pci_dev_put(pdev);
 742
 743         return -ENOMEM;
 744 }
 745
 746 /* Release the framebuffer */
 747 static void hvfb_putmem(struct fb_info *info)
 748 {
 749         struct hvfb_par *par = info->par;
 750
 751         iounmap(info->screen_base);
 752         vmbus_free_mmio(par->mem->start, screen_fb_size);
 753         par->mem = NULL;
 754 }
 755
 756
 757 static int hvfb_probe(struct hv_device *hdev,
 758                       const struct hv_vmbus_device_id *dev_id)
 759 {
 760         struct fb_info *info;
 761         struct hvfb_par *par;
 762         int ret;
 763
 764         info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
 765         if (!info)
 766                 return -ENOMEM;
 767
 768         par = info->par;
 769         par->info = info;
 770         par->fb_ready = false;
 771         init_completion(&par->wait);
 772         INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
 773
 774         /* Connect to VSP */
 775         hv_set_drvdata(hdev, info);
 776         ret = synthvid_connect_vsp(hdev);
 777         if (ret) {
 778                 pr_err("Unable to connect to VSP\n");
 779                 goto error1;
 780         }
 781
 782         ret = hvfb_getmem(hdev, info);
 783         if (ret) {
 784                 pr_err("No memory for framebuffer\n");
 785                 goto error2;
 786         }
 787
 788         hvfb_get_option(info);
 789         pr_info("Screen resolution: %dx%d, Color depth: %d\n",
 790                 screen_width, screen_height, screen_depth);
 791
 792
 793         /* Set up fb_info */
 794         info->flags = FBINFO_DEFAULT;
 795
 796         info->var.xres_virtual = info->var.xres = screen_width;
 797         info->var.yres_virtual = info->var.yres = screen_height;
 798         info->var.bits_per_pixel = screen_depth;
 799
 800         if (info->var.bits_per_pixel == 16) {
 801                 info->var.red = (struct fb_bitfield){11, 5, 0};
 802                 info->var.green = (struct fb_bitfield){5, 6, 0};
 803                 info->var.blue = (struct fb_bitfield){0, 5, 0};
 804                 info->var.transp = (struct fb_bitfield){0, 0, 0};
 805         } else {
 806                 info->var.red = (struct fb_bitfield){16, 8, 0};
 807                 info->var.green = (struct fb_bitfield){8, 8, 0};
 808                 info->var.blue = (struct fb_bitfield){0, 8, 0};
 809                 info->var.transp = (struct fb_bitfield){24, 8, 0};
 810         }
 811
 812         info->var.activate = FB_ACTIVATE_NOW;
 813         info->var.height = -1;
 814         info->var.width = -1;
 815         info->var.vmode = FB_VMODE_NONINTERLACED;
 816
 817         strcpy(info->fix.id, KBUILD_MODNAME);
 818         info->fix.type = FB_TYPE_PACKED_PIXELS;
 819         info->fix.visual = FB_VISUAL_TRUECOLOR;
 820         info->fix.line_length = screen_width * screen_depth / 8;
 821         info->fix.accel = FB_ACCEL_NONE;
 822
 823         info->fbops = &hvfb_ops;
 824         info->pseudo_palette = par->pseudo_palette;
 825
 826         /* Send config to host */
 827         ret = synthvid_send_config(hdev);
 828         if (ret)
 829                 goto error;
 830
 831         ret = register_framebuffer(info);
 832         if (ret) {
 833                 pr_err("Unable to register framebuffer\n");
 834                 goto error;
 835         }
 836
 837         par->fb_ready = true;
 838
 839         par->synchronous_fb = false;
 840         par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
 841         atomic_notifier_chain_register(&panic_notifier_list,
 842                                        &par->hvfb_panic_nb);
 843
 844         return 0;
 845
 846 error:
 847         hvfb_putmem(info);
 848 error2:
 849         vmbus_close(hdev->channel);
 850 error1:
 851         cancel_delayed_work_sync(&par->dwork);
 852         hv_set_drvdata(hdev, NULL);
 853         framebuffer_release(info);
 854         return ret;
 855 }
 856
 857
 858 static int hvfb_remove(struct hv_device *hdev)
 859 {
 860         struct fb_info *info = hv_get_drvdata(hdev);
 861         struct hvfb_par *par = info->par;
 862
 863         atomic_notifier_chain_unregister(&panic_notifier_list,
 864                                          &par->hvfb_panic_nb);
 865
 866         par->update = false;
 867         par->fb_ready = false;
 868
 869         unregister_framebuffer(info);
 870         cancel_delayed_work_sync(&par->dwork);
 871
 872         vmbus_close(hdev->channel);
 873         hv_set_drvdata(hdev, NULL);
 874
 875         hvfb_putmem(info);
 876         framebuffer_release(info);
 877
 878         return 0;
 879 }
 880
 881
 882 static const struct pci_device_id pci_stub_id_table[] = {
 883         {
 884                 .vendor      = PCI_VENDOR_ID_MICROSOFT,
 885                 .device      = PCI_DEVICE_ID_HYPERV_VIDEO,
 886         },
 887         { /* end of list */ }
 888 };
 889
 890 static const struct hv_vmbus_device_id id_table[] = {
 891         /* Synthetic Video Device GUID */
 892         {HV_SYNTHVID_GUID},
 893         {}
 894 };
 895
 896 MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
 897 MODULE_DEVICE_TABLE(vmbus, id_table);
 898
 899 static struct hv_driver hvfb_drv = {
 900         .name = KBUILD_MODNAME,
 901         .id_table = id_table,
 902         .probe = hvfb_probe,
 903         .remove = hvfb_remove,
 904         .driver = {
 905                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 906         },
 907 };
 908
 909 static int hvfb_pci_stub_probe(struct pci_dev *pdev,
 910                                const struct pci_device_id *ent)
 911 {
 912         return 0;
 913 }
 914
 915 static void hvfb_pci_stub_remove(struct pci_dev *pdev)
 916 {
 917 }
 918
 919 static struct pci_driver hvfb_pci_stub_driver = {
 920         .name =         KBUILD_MODNAME,
 921         .id_table =     pci_stub_id_table,
 922         .probe =        hvfb_pci_stub_probe,
 923         .remove =       hvfb_pci_stub_remove,
 924         .driver = {
 925                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 926         }
 927 };
 928
 929 static int __init hvfb_drv_init(void)
 930 {
 931         int ret;
 932
 933         ret = vmbus_driver_register(&hvfb_drv);
 934         if (ret != 0)
 935                 return ret;
 936
 937         ret = pci_register_driver(&hvfb_pci_stub_driver);
 938         if (ret != 0) {
 939                 vmbus_driver_unregister(&hvfb_drv);
 940                 return ret;
 941         }
 942
 943         return 0;
 944 }
 945
 946 static void __exit hvfb_drv_exit(void)
 947 {
 948         pci_unregister_driver(&hvfb_pci_stub_driver);
 949         vmbus_driver_unregister(&hvfb_drv);
 950 }
 951
 952 module_init(hvfb_drv_init);
 953 module_exit(hvfb_drv_exit);
 954
 955 MODULE_LICENSE("GPL");
 956 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");