drivers/video/fbdev/hyperv_fb.c

   1 /*
   2  * Copyright (c) 2012, Microsoft Corporation.
   3  *
   4  * Author:
   5  *   Haiyang Zhang <haiyangz@microsoft.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 as published
   9  * by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  14  * NON INFRINGEMENT.  See the GNU General Public License for more
  15  * details.
  16  */
  17
  18 /*
  19  * Hyper-V Synthetic Video Frame Buffer Driver
  20  *
  21  * This is the driver for the Hyper-V Synthetic Video, which supports
  22  * screen resolution up to Full HD 1920x1080 with 32 bit color on Windows
  23  * Server 2012, and 1600x1200 with 16 bit color on Windows Server 2008 R2
  24  * or earlier.
  25  *
  26  * It also solves the double mouse cursor issue of the emulated video mode.
  27  *
  28  * The default screen resolution is 1152x864, which may be changed by a
  29  * kernel parameter:
  30  *     video=hyperv_fb:<width>x<height>
  31  *     For example: video=hyperv_fb:1280x1024
  32  *
  33  * Portrait orientation is also supported:
  34  *     For example: video=hyperv_fb:864x1152
  35  */
  36
  37 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  38
  39 #include <linux/module.h>
  40 #include <linux/kernel.h>
  41 #include <linux/init.h>
  42 #include <linux/completion.h>
  43 #include <linux/fb.h>
  44 #include <linux/pci.h>
  45 #include <linux/efi.h>
  46
  47 #include <linux/hyperv.h>
  48
  49
  50 /* Hyper-V Synthetic Video Protocol definitions and structures */
  51 #define MAX_VMBUS_PKT_SIZE 0x4000
  52
  53 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
  54 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
  55 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
  56
  57 #define SYNTHVID_DEPTH_WIN7 16
  58 #define SYNTHVID_DEPTH_WIN8 32
  59
  60 #define SYNTHVID_FB_SIZE_WIN7 (4 * 1024 * 1024)
  61 #define SYNTHVID_WIDTH_MAX_WIN7 1600
  62 #define SYNTHVID_HEIGHT_MAX_WIN7 1200
  63
  64 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
  65
  66 #define PCI_VENDOR_ID_MICROSOFT 0x1414
  67 #define PCI_DEVICE_ID_HYPERV_VIDEO 0x5353
  68
  69
  70 enum pipe_msg_type {
  71         PIPE_MSG_INVALID,
  72         PIPE_MSG_DATA,
  73         PIPE_MSG_MAX
  74 };
  75
  76 struct pipe_msg_hdr {
  77         u32 type;
  78         u32 size; /* size of message after this field */
  79 } __packed;
  80
  81
  82 enum synthvid_msg_type {
  83         SYNTHVID_ERROR                  = 0,
  84         SYNTHVID_VERSION_REQUEST        = 1,
  85         SYNTHVID_VERSION_RESPONSE       = 2,
  86         SYNTHVID_VRAM_LOCATION          = 3,
  87         SYNTHVID_VRAM_LOCATION_ACK      = 4,
  88         SYNTHVID_SITUATION_UPDATE       = 5,
  89         SYNTHVID_SITUATION_UPDATE_ACK   = 6,
  90         SYNTHVID_POINTER_POSITION       = 7,
  91         SYNTHVID_POINTER_SHAPE          = 8,
  92         SYNTHVID_FEATURE_CHANGE         = 9,
  93         SYNTHVID_DIRT                   = 10,
  94
  95         SYNTHVID_MAX                    = 11
  96 };
  97
  98 struct synthvid_msg_hdr {
  99         u32 type;
 100         u32 size;  /* size of this header + payload after this field*/
 101 } __packed;
 102
 103
 104 struct synthvid_version_req {
 105         u32 version;
 106 } __packed;
 107
 108 struct synthvid_version_resp {
 109         u32 version;
 110         u8 is_accepted;
 111         u8 max_video_outputs;
 112 } __packed;
 113
 114 struct synthvid_vram_location {
 115         u64 user_ctx;
 116         u8 is_vram_gpa_specified;
 117         u64 vram_gpa;
 118 } __packed;
 119
 120 struct synthvid_vram_location_ack {
 121         u64 user_ctx;
 122 } __packed;
 123
 124 struct video_output_situation {
 125         u8 active;
 126         u32 vram_offset;
 127         u8 depth_bits;
 128         u32 width_pixels;
 129         u32 height_pixels;
 130         u32 pitch_bytes;
 131 } __packed;
 132
 133 struct synthvid_situation_update {
 134         u64 user_ctx;
 135         u8 video_output_count;
 136         struct video_output_situation video_output[1];
 137 } __packed;
 138
 139 struct synthvid_situation_update_ack {
 140         u64 user_ctx;
 141 } __packed;
 142
 143 struct synthvid_pointer_position {
 144         u8 is_visible;
 145         u8 video_output;
 146         s32 image_x;
 147         s32 image_y;
 148 } __packed;
 149
 150
 151 #define CURSOR_MAX_X 96
 152 #define CURSOR_MAX_Y 96
 153 #define CURSOR_ARGB_PIXEL_SIZE 4
 154 #define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE)
 155 #define CURSOR_COMPLETE (-1)
 156
 157 struct synthvid_pointer_shape {
 158         u8 part_idx;
 159         u8 is_argb;
 160         u32 width; /* CURSOR_MAX_X at most */
 161         u32 height; /* CURSOR_MAX_Y at most */
 162         u32 hot_x; /* hotspot relative to upper-left of pointer image */
 163         u32 hot_y;
 164         u8 data[4];
 165 } __packed;
 166
 167 struct synthvid_feature_change {
 168         u8 is_dirt_needed;
 169         u8 is_ptr_pos_needed;
 170         u8 is_ptr_shape_needed;
 171         u8 is_situ_needed;
 172 } __packed;
 173
 174 struct rect {
 175         s32 x1, y1; /* top left corner */
 176         s32 x2, y2; /* bottom right corner, exclusive */
 177 } __packed;
 178
 179 struct synthvid_dirt {
 180         u8 video_output;
 181         u8 dirt_count;
 182         struct rect rect[1];
 183 } __packed;
 184
 185 struct synthvid_msg {
 186         struct pipe_msg_hdr pipe_hdr;
 187         struct synthvid_msg_hdr vid_hdr;
 188         union {
 189                 struct synthvid_version_req ver_req;
 190                 struct synthvid_version_resp ver_resp;
 191                 struct synthvid_vram_location vram;
 192                 struct synthvid_vram_location_ack vram_ack;
 193                 struct synthvid_situation_update situ;
 194                 struct synthvid_situation_update_ack situ_ack;
 195                 struct synthvid_pointer_position ptr_pos;
 196                 struct synthvid_pointer_shape ptr_shape;
 197                 struct synthvid_feature_change feature_chg;
 198                 struct synthvid_dirt dirt;
 199         };
 200 } __packed;
 201
 202
 203
 204 /* FB driver definitions and structures */
 205 #define HVFB_WIDTH 1152 /* default screen width */
 206 #define HVFB_HEIGHT 864 /* default screen height */
 207 #define HVFB_WIDTH_MIN 640
 208 #define HVFB_HEIGHT_MIN 480
 209
 210 #define RING_BUFSIZE (256 * 1024)
 211 #define VSP_TIMEOUT (10 * HZ)
 212 #define HVFB_UPDATE_DELAY (HZ / 20)
 213
 214 struct hvfb_par {
 215         struct fb_info *info;
 216         struct resource *mem;
 217         bool fb_ready; /* fb device is ready */
 218         struct completion wait;
 219         u32 synthvid_version;
 220
 221         struct delayed_work dwork;
 222         bool update;
 223
 224         u32 pseudo_palette[16];
 225         u8 init_buf[MAX_VMBUS_PKT_SIZE];
 226         u8 recv_buf[MAX_VMBUS_PKT_SIZE];
 227
 228         /* If true, the VSC notifies the VSP on every framebuffer change */
 229         bool synchronous_fb;
 230
 231         struct notifier_block hvfb_panic_nb;
 232 };
 233
 234 static uint screen_width = HVFB_WIDTH;
 235 static uint screen_height = HVFB_HEIGHT;
 236 static uint screen_depth;
 237 static uint screen_fb_size;
 238
 239 /* Send message to Hyper-V host */
 240 static inline int synthvid_send(struct hv_device *hdev,
 241                                 struct synthvid_msg *msg)
 242 {
 243         static atomic64_t request_id = ATOMIC64_INIT(0);
 244         int ret;
 245
 246         msg->pipe_hdr.type = PIPE_MSG_DATA;
 247         msg->pipe_hdr.size = msg->vid_hdr.size;
 248
 249         ret = vmbus_sendpacket(hdev->channel, msg,
 250                                msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
 251                                atomic64_inc_return(&request_id),
 252                                VM_PKT_DATA_INBAND, 0);
 253
 254         if (ret)
 255                 pr_err("Unable to send packet via vmbus\n");
 256
 257         return ret;
 258 }
 259
 260
 261 /* Send screen resolution info to host */
 262 static int synthvid_send_situ(struct hv_device *hdev)
 263 {
 264         struct fb_info *info = hv_get_drvdata(hdev);
 265         struct synthvid_msg msg;
 266
 267         if (!info)
 268                 return -ENODEV;
 269
 270         memset(&msg, 0, sizeof(struct synthvid_msg));
 271
 272         msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
 273         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 274                 sizeof(struct synthvid_situation_update);
 275         msg.situ.user_ctx = 0;
 276         msg.situ.video_output_count = 1;
 277         msg.situ.video_output[0].active = 1;
 278         msg.situ.video_output[0].vram_offset = 0;
 279         msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
 280         msg.situ.video_output[0].width_pixels = info->var.xres;
 281         msg.situ.video_output[0].height_pixels = info->var.yres;
 282         msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
 283
 284         synthvid_send(hdev, &msg);
 285
 286         return 0;
 287 }
 288
 289 /* Send mouse pointer info to host */
 290 static int synthvid_send_ptr(struct hv_device *hdev)
 291 {
 292         struct synthvid_msg msg;
 293
 294         memset(&msg, 0, sizeof(struct synthvid_msg));
 295         msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
 296         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 297                 sizeof(struct synthvid_pointer_position);
 298         msg.ptr_pos.is_visible = 1;
 299         msg.ptr_pos.video_output = 0;
 300         msg.ptr_pos.image_x = 0;
 301         msg.ptr_pos.image_y = 0;
 302         synthvid_send(hdev, &msg);
 303
 304         memset(&msg, 0, sizeof(struct synthvid_msg));
 305         msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
 306         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 307                 sizeof(struct synthvid_pointer_shape);
 308         msg.ptr_shape.part_idx = CURSOR_COMPLETE;
 309         msg.ptr_shape.is_argb = 1;
 310         msg.ptr_shape.width = 1;
 311         msg.ptr_shape.height = 1;
 312         msg.ptr_shape.hot_x = 0;
 313         msg.ptr_shape.hot_y = 0;
 314         msg.ptr_shape.data[0] = 0;
 315         msg.ptr_shape.data[1] = 1;
 316         msg.ptr_shape.data[2] = 1;
 317         msg.ptr_shape.data[3] = 1;
 318         synthvid_send(hdev, &msg);
 319
 320         return 0;
 321 }
 322
 323 /* Send updated screen area (dirty rectangle) location to host */
 324 static int synthvid_update(struct fb_info *info)
 325 {
 326         struct hv_device *hdev = device_to_hv_device(info->device);
 327         struct synthvid_msg msg;
 328
 329         memset(&msg, 0, sizeof(struct synthvid_msg));
 330
 331         msg.vid_hdr.type = SYNTHVID_DIRT;
 332         msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 333                 sizeof(struct synthvid_dirt);
 334         msg.dirt.video_output = 0;
 335         msg.dirt.dirt_count = 1;
 336         msg.dirt.rect[0].x1 = 0;
 337         msg.dirt.rect[0].y1 = 0;
 338         msg.dirt.rect[0].x2 = info->var.xres;
 339         msg.dirt.rect[0].y2 = info->var.yres;
 340
 341         synthvid_send(hdev, &msg);
 342
 343         return 0;
 344 }
 345
 346
 347 /*
 348  * Actions on received messages from host:
 349  * Complete the wait event.
 350  * Or, reply with screen and cursor info.
 351  */
 352 static void synthvid_recv_sub(struct hv_device *hdev)
 353 {
 354         struct fb_info *info = hv_get_drvdata(hdev);
 355         struct hvfb_par *par;
 356         struct synthvid_msg *msg;
 357
 358         if (!info)
 359                 return;
 360
 361         par = info->par;
 362         msg = (struct synthvid_msg *)par->recv_buf;
 363
 364         /* Complete the wait event */
 365         if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
 366             msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
 367                 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
 368                 complete(&par->wait);
 369                 return;
 370         }
 371
 372         /* Reply with screen and cursor info */
 373         if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
 374                 if (par->fb_ready) {
 375                         synthvid_send_ptr(hdev);
 376                         synthvid_send_situ(hdev);
 377                 }
 378
 379                 par->update = msg->feature_chg.is_dirt_needed;
 380                 if (par->update)
 381                         schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
 382         }
 383 }
 384
 385 /* Receive callback for messages from the host */
 386 static void synthvid_receive(void *ctx)
 387 {
 388         struct hv_device *hdev = ctx;
 389         struct fb_info *info = hv_get_drvdata(hdev);
 390         struct hvfb_par *par;
 391         struct synthvid_msg *recv_buf;
 392         u32 bytes_recvd;
 393         u64 req_id;
 394         int ret;
 395
 396         if (!info)
 397                 return;
 398
 399         par = info->par;
 400         recv_buf = (struct synthvid_msg *)par->recv_buf;
 401
 402         do {
 403                 ret = vmbus_recvpacket(hdev->channel, recv_buf,
 404                                        MAX_VMBUS_PKT_SIZE,
 405                                        &bytes_recvd, &req_id);
 406                 if (bytes_recvd > 0 &&
 407                     recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
 408                         synthvid_recv_sub(hdev);
 409         } while (bytes_recvd > 0 && ret == 0);
 410 }
 411
 412 /* Check synthetic video protocol version with the host */
 413 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
 414 {
 415         struct fb_info *info = hv_get_drvdata(hdev);
 416         struct hvfb_par *par = info->par;
 417         struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
 418         int ret = 0;
 419         unsigned long t;
 420
 421         memset(msg, 0, sizeof(struct synthvid_msg));
 422         msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
 423         msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 424                 sizeof(struct synthvid_version_req);
 425         msg->ver_req.version = ver;
 426         synthvid_send(hdev, msg);
 427
 428         t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
 429         if (!t) {
 430                 pr_err("Time out on waiting version response\n");
 431                 ret = -ETIMEDOUT;
 432                 goto out;
 433         }
 434         if (!msg->ver_resp.is_accepted) {
 435                 ret = -ENODEV;
 436                 goto out;
 437         }
 438
 439         par->synthvid_version = ver;
 440
 441 out:
 442         return ret;
 443 }
 444
 445 /* Connect to VSP (Virtual Service Provider) on host */
 446 static int synthvid_connect_vsp(struct hv_device *hdev)
 447 {
 448         struct fb_info *info = hv_get_drvdata(hdev);
 449         struct hvfb_par *par = info->par;
 450         int ret;
 451
 452         ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
 453                          NULL, 0, synthvid_receive, hdev);
 454         if (ret) {
 455                 pr_err("Unable to open vmbus channel\n");
 456                 return ret;
 457         }
 458
 459         /* Negotiate the protocol version with host */
 460         if (vmbus_proto_version == VERSION_WS2008 ||
 461             vmbus_proto_version == VERSION_WIN7)
 462                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN7);
 463         else
 464                 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
 465
 466         if (ret) {
 467                 pr_err("Synthetic video device version not accepted\n");
 468                 goto error;
 469         }
 470
 471         if (par->synthvid_version == SYNTHVID_VERSION_WIN7)
 472                 screen_depth = SYNTHVID_DEPTH_WIN7;
 473         else
 474                 screen_depth = SYNTHVID_DEPTH_WIN8;
 475
 476         screen_fb_size = hdev->channel->offermsg.offer.
 477                                 mmio_megabytes * 1024 * 1024;
 478
 479         return 0;
 480
 481 error:
 482         vmbus_close(hdev->channel);
 483         return ret;
 484 }
 485
 486 /* Send VRAM and Situation messages to the host */
 487 static int synthvid_send_config(struct hv_device *hdev)
 488 {
 489         struct fb_info *info = hv_get_drvdata(hdev);
 490         struct hvfb_par *par = info->par;
 491         struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
 492         int ret = 0;
 493         unsigned long t;
 494
 495         /* Send VRAM location */
 496         memset(msg, 0, sizeof(struct synthvid_msg));
 497         msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
 498         msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 499                 sizeof(struct synthvid_vram_location);
 500         msg->vram.user_ctx = msg->vram.vram_gpa = info->fix.smem_start;
 501         msg->vram.is_vram_gpa_specified = 1;
 502         synthvid_send(hdev, msg);
 503
 504         t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
 505         if (!t) {
 506                 pr_err("Time out on waiting vram location ack\n");
 507                 ret = -ETIMEDOUT;
 508                 goto out;
 509         }
 510         if (msg->vram_ack.user_ctx != info->fix.smem_start) {
 511                 pr_err("Unable to set VRAM location\n");
 512                 ret = -ENODEV;
 513                 goto out;
 514         }
 515
 516         /* Send pointer and situation update */
 517         synthvid_send_ptr(hdev);
 518         synthvid_send_situ(hdev);
 519
 520 out:
 521         return ret;
 522 }
 523
 524
 525 /*
 526  * Delayed work callback:
 527  * It is called at HVFB_UPDATE_DELAY or longer time interval to process
 528  * screen updates. It is re-scheduled if further update is necessary.
 529  */
 530 static void hvfb_update_work(struct work_struct *w)
 531 {
 532         struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
 533         struct fb_info *info = par->info;
 534
 535         if (par->fb_ready)
 536                 synthvid_update(info);
 537
 538         if (par->update)
 539                 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
 540 }
 541
 542 static int hvfb_on_panic(struct notifier_block *nb,
 543                          unsigned long e, void *p)
 544 {
 545         struct hvfb_par *par;
 546         struct fb_info *info;
 547
 548         par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
 549         par->synchronous_fb = true;
 550         info = par->info;
 551         synthvid_update(info);
 552
 553         return NOTIFY_DONE;
 554 }
 555
 556 /* Framebuffer operation handlers */
 557
 558 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
 559 {
 560         if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
 561             var->xres > screen_width || var->yres >  screen_height ||
 562             var->bits_per_pixel != screen_depth)
 563                 return -EINVAL;
 564
 565         var->xres_virtual = var->xres;
 566         var->yres_virtual = var->yres;
 567
 568         return 0;
 569 }
 570
 571 static int hvfb_set_par(struct fb_info *info)
 572 {
 573         struct hv_device *hdev = device_to_hv_device(info->device);
 574
 575         return synthvid_send_situ(hdev);
 576 }
 577
 578
 579 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
 580 {
 581         return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
 582 }
 583
 584 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
 585                           unsigned blue, unsigned transp, struct fb_info *info)
 586 {
 587         u32 *pal = info->pseudo_palette;
 588
 589         if (regno > 15)
 590                 return -EINVAL;
 591
 592         pal[regno] = chan_to_field(red, &info->var.red)
 593                 | chan_to_field(green, &info->var.green)
 594                 | chan_to_field(blue, &info->var.blue)
 595                 | chan_to_field(transp, &info->var.transp);
 596
 597         return 0;
 598 }
 599
 600 static int hvfb_blank(int blank, struct fb_info *info)
 601 {
 602         return 1;       /* get fb_blank to set the colormap to all black */
 603 }
 604
 605 static void hvfb_cfb_fillrect(struct fb_info *p,
 606                               const struct fb_fillrect *rect)
 607 {
 608         struct hvfb_par *par = p->par;
 609
 610         cfb_fillrect(p, rect);
 611         if (par->synchronous_fb)
 612                 synthvid_update(p);
 613 }
 614
 615 static void hvfb_cfb_copyarea(struct fb_info *p,
 616                               const struct fb_copyarea *area)
 617 {
 618         struct hvfb_par *par = p->par;
 619
 620         cfb_copyarea(p, area);
 621         if (par->synchronous_fb)
 622                 synthvid_update(p);
 623 }
 624
 625 static void hvfb_cfb_imageblit(struct fb_info *p,
 626                                const struct fb_image *image)
 627 {
 628         struct hvfb_par *par = p->par;
 629
 630         cfb_imageblit(p, image);
 631         if (par->synchronous_fb)
 632                 synthvid_update(p);
 633 }
 634
 635 static struct fb_ops hvfb_ops = {
 636         .owner = THIS_MODULE,
 637         .fb_check_var = hvfb_check_var,
 638         .fb_set_par = hvfb_set_par,
 639         .fb_setcolreg = hvfb_setcolreg,
 640         .fb_fillrect = hvfb_cfb_fillrect,
 641         .fb_copyarea = hvfb_cfb_copyarea,
 642         .fb_imageblit = hvfb_cfb_imageblit,
 643         .fb_blank = hvfb_blank,
 644 };
 645
 646
 647 /* Get options from kernel paramenter "video=" */
 648 static void hvfb_get_option(struct fb_info *info)
 649 {
 650         struct hvfb_par *par = info->par;
 651         char *opt = NULL, *p;
 652         uint x = 0, y = 0;
 653
 654         if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
 655                 return;
 656
 657         p = strsep(&opt, "x");
 658         if (!*p || kstrtouint(p, 0, &x) ||
 659             !opt || !*opt || kstrtouint(opt, 0, &y)) {
 660                 pr_err("Screen option is invalid: skipped\n");
 661                 return;
 662         }
 663
 664         if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
 665             (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
 666              x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8) ||
 667             (par->synthvid_version == SYNTHVID_VERSION_WIN7 &&
 668              (x > SYNTHVID_WIDTH_MAX_WIN7 || y > SYNTHVID_HEIGHT_MAX_WIN7))) {
 669                 pr_err("Screen resolution option is out of range: skipped\n");
 670                 return;
 671         }
 672
 673         screen_width = x;
 674         screen_height = y;
 675         return;
 676 }
 677
 678
 679 /* Get framebuffer memory from Hyper-V video pci space */
 680 static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
 681 {
 682         struct hvfb_par *par = info->par;
 683         struct pci_dev *pdev  = NULL;
 684         void __iomem *fb_virt;
 685         int gen2vm = efi_enabled(EFI_BOOT);
 686         resource_size_t pot_start, pot_end;
 687         int ret;
 688
 689         if (gen2vm) {
 690                 pot_start = 0;
 691                 pot_end = -1;
 692         } else {
 693                 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
 694                               PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
 695                 if (!pdev) {
 696                         pr_err("Unable to find PCI Hyper-V video\n");
 697                         return -ENODEV;
 698                 }
 699
 700                 if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
 701                     pci_resource_len(pdev, 0) < screen_fb_size)
 702                         goto err1;
 703
 704                 pot_end = pci_resource_end(pdev, 0);
 705                 pot_start = pot_end - screen_fb_size + 1;
 706         }
 707
 708         ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
 709                                   screen_fb_size, 0x100000, true);
 710         if (ret != 0) {
 711                 pr_err("Unable to allocate framebuffer memory\n");
 712                 goto err1;
 713         }
 714
 715         fb_virt = ioremap(par->mem->start, screen_fb_size);
 716         if (!fb_virt)
 717                 goto err2;
 718
 719         info->apertures = alloc_apertures(1);
 720         if (!info->apertures)
 721                 goto err3;
 722
 723         if (gen2vm) {
 724                 info->apertures->ranges[0].base = screen_info.lfb_base;
 725                 info->apertures->ranges[0].size = screen_info.lfb_size;
 726                 remove_conflicting_framebuffers(info->apertures,
 727                                                 KBUILD_MODNAME, false);
 728         } else {
 729                 info->apertures->ranges[0].base = pci_resource_start(pdev, 0);
 730                 info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
 731         }
 732
 733         info->fix.smem_start = par->mem->start;
 734         info->fix.smem_len = screen_fb_size;
 735         info->screen_base = fb_virt;
 736         info->screen_size = screen_fb_size;
 737
 738         if (!gen2vm)
 739                 pci_dev_put(pdev);
 740
 741         return 0;
 742
 743 err3:
 744         iounmap(fb_virt);
 745 err2:
 746         vmbus_free_mmio(par->mem->start, screen_fb_size);
 747         par->mem = NULL;
 748 err1:
 749         if (!gen2vm)
 750                 pci_dev_put(pdev);
 751
 752         return -ENOMEM;
 753 }
 754
 755 /* Release the framebuffer */
 756 static void hvfb_putmem(struct fb_info *info)
 757 {
 758         struct hvfb_par *par = info->par;
 759
 760         iounmap(info->screen_base);
 761         vmbus_free_mmio(par->mem->start, screen_fb_size);
 762         par->mem = NULL;
 763 }
 764
 765
 766 static int hvfb_probe(struct hv_device *hdev,
 767                       const struct hv_vmbus_device_id *dev_id)
 768 {
 769         struct fb_info *info;
 770         struct hvfb_par *par;
 771         int ret;
 772
 773         info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
 774         if (!info) {
 775                 pr_err("No memory for framebuffer info\n");
 776                 return -ENOMEM;
 777         }
 778
 779         par = info->par;
 780         par->info = info;
 781         par->fb_ready = false;
 782         init_completion(&par->wait);
 783         INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
 784
 785         /* Connect to VSP */
 786         hv_set_drvdata(hdev, info);
 787         ret = synthvid_connect_vsp(hdev);
 788         if (ret) {
 789                 pr_err("Unable to connect to VSP\n");
 790                 goto error1;
 791         }
 792
 793         ret = hvfb_getmem(hdev, info);
 794         if (ret) {
 795                 pr_err("No memory for framebuffer\n");
 796                 goto error2;
 797         }
 798
 799         hvfb_get_option(info);
 800         pr_info("Screen resolution: %dx%d, Color depth: %d\n",
 801                 screen_width, screen_height, screen_depth);
 802
 803
 804         /* Set up fb_info */
 805         info->flags = FBINFO_DEFAULT;
 806
 807         info->var.xres_virtual = info->var.xres = screen_width;
 808         info->var.yres_virtual = info->var.yres = screen_height;
 809         info->var.bits_per_pixel = screen_depth;
 810
 811         if (info->var.bits_per_pixel == 16) {
 812                 info->var.red = (struct fb_bitfield){11, 5, 0};
 813                 info->var.green = (struct fb_bitfield){5, 6, 0};
 814                 info->var.blue = (struct fb_bitfield){0, 5, 0};
 815                 info->var.transp = (struct fb_bitfield){0, 0, 0};
 816         } else {
 817                 info->var.red = (struct fb_bitfield){16, 8, 0};
 818                 info->var.green = (struct fb_bitfield){8, 8, 0};
 819                 info->var.blue = (struct fb_bitfield){0, 8, 0};
 820                 info->var.transp = (struct fb_bitfield){24, 8, 0};
 821         }
 822
 823         info->var.activate = FB_ACTIVATE_NOW;
 824         info->var.height = -1;
 825         info->var.width = -1;
 826         info->var.vmode = FB_VMODE_NONINTERLACED;
 827
 828         strcpy(info->fix.id, KBUILD_MODNAME);
 829         info->fix.type = FB_TYPE_PACKED_PIXELS;
 830         info->fix.visual = FB_VISUAL_TRUECOLOR;
 831         info->fix.line_length = screen_width * screen_depth / 8;
 832         info->fix.accel = FB_ACCEL_NONE;
 833
 834         info->fbops = &hvfb_ops;
 835         info->pseudo_palette = par->pseudo_palette;
 836
 837         /* Send config to host */
 838         ret = synthvid_send_config(hdev);
 839         if (ret)
 840                 goto error;
 841
 842         ret = register_framebuffer(info);
 843         if (ret) {
 844                 pr_err("Unable to register framebuffer\n");
 845                 goto error;
 846         }
 847
 848         par->fb_ready = true;
 849
 850         par->synchronous_fb = false;
 851         par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
 852         atomic_notifier_chain_register(&panic_notifier_list,
 853                                        &par->hvfb_panic_nb);
 854
 855         return 0;
 856
 857 error:
 858         hvfb_putmem(info);
 859 error2:
 860         vmbus_close(hdev->channel);
 861 error1:
 862         cancel_delayed_work_sync(&par->dwork);
 863         hv_set_drvdata(hdev, NULL);
 864         framebuffer_release(info);
 865         return ret;
 866 }
 867
 868
 869 static int hvfb_remove(struct hv_device *hdev)
 870 {
 871         struct fb_info *info = hv_get_drvdata(hdev);
 872         struct hvfb_par *par = info->par;
 873
 874         atomic_notifier_chain_unregister(&panic_notifier_list,
 875                                          &par->hvfb_panic_nb);
 876
 877         par->update = false;
 878         par->fb_ready = false;
 879
 880         unregister_framebuffer(info);
 881         cancel_delayed_work_sync(&par->dwork);
 882
 883         vmbus_close(hdev->channel);
 884         hv_set_drvdata(hdev, NULL);
 885
 886         hvfb_putmem(info);
 887         framebuffer_release(info);
 888
 889         return 0;
 890 }
 891
 892
 893 static const struct pci_device_id pci_stub_id_table[] = {
 894         {
 895                 .vendor      = PCI_VENDOR_ID_MICROSOFT,
 896                 .device      = PCI_DEVICE_ID_HYPERV_VIDEO,
 897         },
 898         { /* end of list */ }
 899 };
 900
 901 static const struct hv_vmbus_device_id id_table[] = {
 902         /* Synthetic Video Device GUID */
 903         {HV_SYNTHVID_GUID},
 904         {}
 905 };
 906
 907 MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
 908 MODULE_DEVICE_TABLE(vmbus, id_table);
 909
 910 static struct hv_driver hvfb_drv = {
 911         .name = KBUILD_MODNAME,
 912         .id_table = id_table,
 913         .probe = hvfb_probe,
 914         .remove = hvfb_remove,
 915 };
 916
 917 static int hvfb_pci_stub_probe(struct pci_dev *pdev,
 918                                const struct pci_device_id *ent)
 919 {
 920         return 0;
 921 }
 922
 923 static void hvfb_pci_stub_remove(struct pci_dev *pdev)
 924 {
 925 }
 926
 927 static struct pci_driver hvfb_pci_stub_driver = {
 928         .name =         KBUILD_MODNAME,
 929         .id_table =     pci_stub_id_table,
 930         .probe =        hvfb_pci_stub_probe,
 931         .remove =       hvfb_pci_stub_remove,
 932 };
 933
 934 static int __init hvfb_drv_init(void)
 935 {
 936         int ret;
 937
 938         ret = vmbus_driver_register(&hvfb_drv);
 939         if (ret != 0)
 940                 return ret;
 941
 942         ret = pci_register_driver(&hvfb_pci_stub_driver);
 943         if (ret != 0) {
 944                 vmbus_driver_unregister(&hvfb_drv);
 945                 return ret;
 946         }
 947
 948         return 0;
 949 }
 950
 951 static void __exit hvfb_drv_exit(void)
 952 {
 953         pci_unregister_driver(&hvfb_pci_stub_driver);
 954         vmbus_driver_unregister(&hvfb_drv);
 955 }
 956
 957 module_init(hvfb_drv_init);
 958 module_exit(hvfb_drv_exit);
 959
 960 MODULE_LICENSE("GPL");
 961 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");