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/aperture.h>
49#include <linux/module.h>
50#include <linux/kernel.h>
51#include <linux/vmalloc.h>
52#include <linux/init.h>
53#include <linux/completion.h>
54#include <linux/fb.h>
55#include <linux/pci.h>
56#include <linux/panic_notifier.h>
57#include <linux/efi.h>
58#include <linux/console.h>
59
60#include <linux/hyperv.h>
61
62/* Hyper-V Synthetic Video Protocol definitions and structures */
63#define MAX_VMBUS_PKT_SIZE 0x4000
64
65#define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
66/* Support for VERSION_WIN7 is removed. #define is retained for reference. */
67#define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
68#define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
69#define SYNTHVID_VERSION_WIN10 SYNTHVID_VERSION(3, 5)
70
71#define SYNTHVID_VER_GET_MAJOR(ver) (ver & 0x0000ffff)
72#define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16)
73
74#define SYNTHVID_DEPTH_WIN8 32
75#define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
76
77enum pipe_msg_type {
78 PIPE_MSG_INVALID,
79 PIPE_MSG_DATA,
80 PIPE_MSG_MAX
81};
82
83struct pipe_msg_hdr {
84 u32 type;
85 u32 size; /* size of message after this field */
86} __packed;
87
88
89enum synthvid_msg_type {
90 SYNTHVID_ERROR = 0,
91 SYNTHVID_VERSION_REQUEST = 1,
92 SYNTHVID_VERSION_RESPONSE = 2,
93 SYNTHVID_VRAM_LOCATION = 3,
94 SYNTHVID_VRAM_LOCATION_ACK = 4,
95 SYNTHVID_SITUATION_UPDATE = 5,
96 SYNTHVID_SITUATION_UPDATE_ACK = 6,
97 SYNTHVID_POINTER_POSITION = 7,
98 SYNTHVID_POINTER_SHAPE = 8,
99 SYNTHVID_FEATURE_CHANGE = 9,
100 SYNTHVID_DIRT = 10,
101 SYNTHVID_RESOLUTION_REQUEST = 13,
102 SYNTHVID_RESOLUTION_RESPONSE = 14,
103
104 SYNTHVID_MAX = 15
105};
106
107#define SYNTHVID_EDID_BLOCK_SIZE 128
108#define SYNTHVID_MAX_RESOLUTION_COUNT 64
109
110struct hvd_screen_info {
111 u16 width;
112 u16 height;
113} __packed;
114
115struct synthvid_msg_hdr {
116 u32 type;
117 u32 size; /* size of this header + payload after this field*/
118} __packed;
119
120struct synthvid_version_req {
121 u32 version;
122} __packed;
123
124struct synthvid_version_resp {
125 u32 version;
126 u8 is_accepted;
127 u8 max_video_outputs;
128} __packed;
129
130struct synthvid_supported_resolution_req {
131 u8 maximum_resolution_count;
132} __packed;
133
134struct synthvid_supported_resolution_resp {
135 u8 edid_block[SYNTHVID_EDID_BLOCK_SIZE];
136 u8 resolution_count;
137 u8 default_resolution_index;
138 u8 is_standard;
139 struct hvd_screen_info
140 supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT];
141} __packed;
142
143struct synthvid_vram_location {
144 u64 user_ctx;
145 u8 is_vram_gpa_specified;
146 u64 vram_gpa;
147} __packed;
148
149struct synthvid_vram_location_ack {
150 u64 user_ctx;
151} __packed;
152
153struct video_output_situation {
154 u8 active;
155 u32 vram_offset;
156 u8 depth_bits;
157 u32 width_pixels;
158 u32 height_pixels;
159 u32 pitch_bytes;
160} __packed;
161
162struct synthvid_situation_update {
163 u64 user_ctx;
164 u8 video_output_count;
165 struct video_output_situation video_output[1];
166} __packed;
167
168struct synthvid_situation_update_ack {
169 u64 user_ctx;
170} __packed;
171
172struct synthvid_pointer_position {
173 u8 is_visible;
174 u8 video_output;
175 s32 image_x;
176 s32 image_y;
177} __packed;
178
179
180#define CURSOR_MAX_X 96
181#define CURSOR_MAX_Y 96
182#define CURSOR_ARGB_PIXEL_SIZE 4
183#define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE)
184#define CURSOR_COMPLETE (-1)
185
186struct synthvid_pointer_shape {
187 u8 part_idx;
188 u8 is_argb;
189 u32 width; /* CURSOR_MAX_X at most */
190 u32 height; /* CURSOR_MAX_Y at most */
191 u32 hot_x; /* hotspot relative to upper-left of pointer image */
192 u32 hot_y;
193 u8 data[4];
194} __packed;
195
196struct synthvid_feature_change {
197 u8 is_dirt_needed;
198 u8 is_ptr_pos_needed;
199 u8 is_ptr_shape_needed;
200 u8 is_situ_needed;
201} __packed;
202
203struct rect {
204 s32 x1, y1; /* top left corner */
205 s32 x2, y2; /* bottom right corner, exclusive */
206} __packed;
207
208struct synthvid_dirt {
209 u8 video_output;
210 u8 dirt_count;
211 struct rect rect[1];
212} __packed;
213
214struct synthvid_msg {
215 struct pipe_msg_hdr pipe_hdr;
216 struct synthvid_msg_hdr vid_hdr;
217 union {
218 struct synthvid_version_req ver_req;
219 struct synthvid_version_resp ver_resp;
220 struct synthvid_vram_location vram;
221 struct synthvid_vram_location_ack vram_ack;
222 struct synthvid_situation_update situ;
223 struct synthvid_situation_update_ack situ_ack;
224 struct synthvid_pointer_position ptr_pos;
225 struct synthvid_pointer_shape ptr_shape;
226 struct synthvid_feature_change feature_chg;
227 struct synthvid_dirt dirt;
228 struct synthvid_supported_resolution_req resolution_req;
229 struct synthvid_supported_resolution_resp resolution_resp;
230 };
231} __packed;
232
233
234/* FB driver definitions and structures */
235#define HVFB_WIDTH 1152 /* default screen width */
236#define HVFB_HEIGHT 864 /* default screen height */
237#define HVFB_WIDTH_MIN 640
238#define HVFB_HEIGHT_MIN 480
239
240#define RING_BUFSIZE (256 * 1024)
241#define VSP_TIMEOUT (10 * HZ)
242#define HVFB_UPDATE_DELAY (HZ / 20)
243#define HVFB_ONDEMAND_THROTTLE (HZ / 20)
244
245struct hvfb_par {
246 struct fb_info *info;
247 struct resource *mem;
248 bool fb_ready; /* fb device is ready */
249 struct completion wait;
250 u32 synthvid_version;
251
252 struct delayed_work dwork;
253 bool update;
254 bool update_saved; /* The value of 'update' before hibernation */
255
256 u32 pseudo_palette[16];
257 u8 init_buf[MAX_VMBUS_PKT_SIZE];
258 u8 recv_buf[MAX_VMBUS_PKT_SIZE];
259
260 /* If true, the VSC notifies the VSP on every framebuffer change */
261 bool synchronous_fb;
262
263 /* If true, need to copy from deferred IO mem to framebuffer mem */
264 bool need_docopy;
265
266 struct notifier_block hvfb_panic_nb;
267
268 /* Memory for deferred IO and frame buffer itself */
269 unsigned char *dio_vp;
270 unsigned char *mmio_vp;
271 phys_addr_t mmio_pp;
272
273 /* Dirty rectangle, protected by delayed_refresh_lock */
274 int x1, y1, x2, y2;
275 bool delayed_refresh;
276 spinlock_t delayed_refresh_lock;
277};
278
279static uint screen_width = HVFB_WIDTH;
280static uint screen_height = HVFB_HEIGHT;
281static uint screen_depth;
282static uint screen_fb_size;
283static uint dio_fb_size; /* FB size for deferred IO */
284
285static void hvfb_putmem(struct fb_info *info);
286
287/* Send message to Hyper-V host */
288static inline int synthvid_send(struct hv_device *hdev,
289 struct synthvid_msg *msg)
290{
291 static atomic64_t request_id = ATOMIC64_INIT(0);
292 int ret;
293
294 msg->pipe_hdr.type = PIPE_MSG_DATA;
295 msg->pipe_hdr.size = msg->vid_hdr.size;
296
297 ret = vmbus_sendpacket(channel: hdev->channel, buffer: msg,
298 bufferLen: msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
299 requestid: atomic64_inc_return(v: &request_id),
300 type: VM_PKT_DATA_INBAND, flags: 0);
301
302 if (ret)
303 pr_err_ratelimited("Unable to send packet via vmbus; error %d\n", ret);
304
305 return ret;
306}
307
308
309/* Send screen resolution info to host */
310static int synthvid_send_situ(struct hv_device *hdev)
311{
312 struct fb_info *info = hv_get_drvdata(dev: hdev);
313 struct synthvid_msg msg;
314
315 if (!info)
316 return -ENODEV;
317
318 memset(&msg, 0, sizeof(struct synthvid_msg));
319
320 msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
321 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
322 sizeof(struct synthvid_situation_update);
323 msg.situ.user_ctx = 0;
324 msg.situ.video_output_count = 1;
325 msg.situ.video_output[0].active = 1;
326 msg.situ.video_output[0].vram_offset = 0;
327 msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
328 msg.situ.video_output[0].width_pixels = info->var.xres;
329 msg.situ.video_output[0].height_pixels = info->var.yres;
330 msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
331
332 synthvid_send(hdev, msg: &msg);
333
334 return 0;
335}
336
337/* Send mouse pointer info to host */
338static int synthvid_send_ptr(struct hv_device *hdev)
339{
340 struct synthvid_msg msg;
341
342 memset(&msg, 0, sizeof(struct synthvid_msg));
343 msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
344 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
345 sizeof(struct synthvid_pointer_position);
346 msg.ptr_pos.is_visible = 1;
347 msg.ptr_pos.video_output = 0;
348 msg.ptr_pos.image_x = 0;
349 msg.ptr_pos.image_y = 0;
350 synthvid_send(hdev, msg: &msg);
351
352 memset(&msg, 0, sizeof(struct synthvid_msg));
353 msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
354 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
355 sizeof(struct synthvid_pointer_shape);
356 msg.ptr_shape.part_idx = CURSOR_COMPLETE;
357 msg.ptr_shape.is_argb = 1;
358 msg.ptr_shape.width = 1;
359 msg.ptr_shape.height = 1;
360 msg.ptr_shape.hot_x = 0;
361 msg.ptr_shape.hot_y = 0;
362 msg.ptr_shape.data[0] = 0;
363 msg.ptr_shape.data[1] = 1;
364 msg.ptr_shape.data[2] = 1;
365 msg.ptr_shape.data[3] = 1;
366 synthvid_send(hdev, msg: &msg);
367
368 return 0;
369}
370
371/* Send updated screen area (dirty rectangle) location to host */
372static int
373synthvid_update(struct fb_info *info, int x1, int y1, int x2, int y2)
374{
375 struct hv_device *hdev = device_to_hv_device(info->device);
376 struct synthvid_msg msg;
377
378 memset(&msg, 0, sizeof(struct synthvid_msg));
379 if (x2 == INT_MAX)
380 x2 = info->var.xres;
381 if (y2 == INT_MAX)
382 y2 = info->var.yres;
383
384 msg.vid_hdr.type = SYNTHVID_DIRT;
385 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
386 sizeof(struct synthvid_dirt);
387 msg.dirt.video_output = 0;
388 msg.dirt.dirt_count = 1;
389 msg.dirt.rect[0].x1 = (x1 > x2) ? 0 : x1;
390 msg.dirt.rect[0].y1 = (y1 > y2) ? 0 : y1;
391 msg.dirt.rect[0].x2 =
392 (x2 < x1 || x2 > info->var.xres) ? info->var.xres : x2;
393 msg.dirt.rect[0].y2 =
394 (y2 < y1 || y2 > info->var.yres) ? info->var.yres : y2;
395
396 synthvid_send(hdev, msg: &msg);
397
398 return 0;
399}
400
401static void hvfb_docopy(struct hvfb_par *par,
402 unsigned long offset,
403 unsigned long size)
404{
405 if (!par || !par->mmio_vp || !par->dio_vp || !par->fb_ready ||
406 size == 0 || offset >= dio_fb_size)
407 return;
408
409 if (offset + size > dio_fb_size)
410 size = dio_fb_size - offset;
411
412 memcpy(par->mmio_vp + offset, par->dio_vp + offset, size);
413}
414
415/* Deferred IO callback */
416static void synthvid_deferred_io(struct fb_info *p, struct list_head *pagereflist)
417{
418 struct hvfb_par *par = p->par;
419 struct fb_deferred_io_pageref *pageref;
420 unsigned long start, end;
421 int y1, y2, miny, maxy;
422
423 miny = INT_MAX;
424 maxy = 0;
425
426 /*
427 * Merge dirty pages. It is possible that last page cross
428 * over the end of frame buffer row yres. This is taken care of
429 * in synthvid_update function by clamping the y2
430 * value to yres.
431 */
432 list_for_each_entry(pageref, pagereflist, list) {
433 start = pageref->offset;
434 end = start + PAGE_SIZE - 1;
435 y1 = start / p->fix.line_length;
436 y2 = end / p->fix.line_length;
437 miny = min_t(int, miny, y1);
438 maxy = max_t(int, maxy, y2);
439
440 /* Copy from dio space to mmio address */
441 if (par->fb_ready && par->need_docopy)
442 hvfb_docopy(par, offset: start, PAGE_SIZE);
443 }
444
445 if (par->fb_ready && par->update)
446 synthvid_update(info: p, x1: 0, y1: miny, x2: p->var.xres, y2: maxy + 1);
447}
448
449static struct fb_deferred_io synthvid_defio = {
450 .delay = HZ / 20,
451 .deferred_io = synthvid_deferred_io,
452};
453
454/*
455 * Actions on received messages from host:
456 * Complete the wait event.
457 * Or, reply with screen and cursor info.
458 */
459static void synthvid_recv_sub(struct hv_device *hdev)
460{
461 struct fb_info *info = hv_get_drvdata(dev: hdev);
462 struct hvfb_par *par;
463 struct synthvid_msg *msg;
464
465 if (!info)
466 return;
467
468 par = info->par;
469 msg = (struct synthvid_msg *)par->recv_buf;
470
471 /* Complete the wait event */
472 if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
473 msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE ||
474 msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
475 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
476 complete(&par->wait);
477 return;
478 }
479
480 /* Reply with screen and cursor info */
481 if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
482 if (par->fb_ready) {
483 synthvid_send_ptr(hdev);
484 synthvid_send_situ(hdev);
485 }
486
487 par->update = msg->feature_chg.is_dirt_needed;
488 if (par->update)
489 schedule_delayed_work(dwork: &par->dwork, HVFB_UPDATE_DELAY);
490 }
491}
492
493/* Receive callback for messages from the host */
494static void synthvid_receive(void *ctx)
495{
496 struct hv_device *hdev = ctx;
497 struct fb_info *info = hv_get_drvdata(dev: hdev);
498 struct hvfb_par *par;
499 struct synthvid_msg *recv_buf;
500 u32 bytes_recvd;
501 u64 req_id;
502 int ret;
503
504 if (!info)
505 return;
506
507 par = info->par;
508 recv_buf = (struct synthvid_msg *)par->recv_buf;
509
510 do {
511 ret = vmbus_recvpacket(channel: hdev->channel, buffer: recv_buf,
512 MAX_VMBUS_PKT_SIZE,
513 buffer_actual_len: &bytes_recvd, requestid: &req_id);
514 if (bytes_recvd > 0 &&
515 recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
516 synthvid_recv_sub(hdev);
517 } while (bytes_recvd > 0 && ret == 0);
518}
519
520/* Check if the ver1 version is equal or greater than ver2 */
521static inline bool synthvid_ver_ge(u32 ver1, u32 ver2)
522{
523 if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) ||
524 (SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) &&
525 SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2)))
526 return true;
527
528 return false;
529}
530
531/* Check synthetic video protocol version with the host */
532static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
533{
534 struct fb_info *info = hv_get_drvdata(dev: hdev);
535 struct hvfb_par *par = info->par;
536 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
537 int ret = 0;
538 unsigned long t;
539
540 memset(msg, 0, sizeof(struct synthvid_msg));
541 msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
542 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
543 sizeof(struct synthvid_version_req);
544 msg->ver_req.version = ver;
545 synthvid_send(hdev, msg);
546
547 t = wait_for_completion_timeout(x: &par->wait, VSP_TIMEOUT);
548 if (!t) {
549 pr_err("Time out on waiting version response\n");
550 ret = -ETIMEDOUT;
551 goto out;
552 }
553 if (!msg->ver_resp.is_accepted) {
554 ret = -ENODEV;
555 goto out;
556 }
557
558 par->synthvid_version = ver;
559 pr_info("Synthvid Version major %d, minor %d\n",
560 SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver));
561
562out:
563 return ret;
564}
565
566/* Get current resolution from the host */
567static int synthvid_get_supported_resolution(struct hv_device *hdev)
568{
569 struct fb_info *info = hv_get_drvdata(dev: hdev);
570 struct hvfb_par *par = info->par;
571 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
572 int ret = 0;
573 unsigned long t;
574 u8 index;
575
576 memset(msg, 0, sizeof(struct synthvid_msg));
577 msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST;
578 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
579 sizeof(struct synthvid_supported_resolution_req);
580
581 msg->resolution_req.maximum_resolution_count =
582 SYNTHVID_MAX_RESOLUTION_COUNT;
583 synthvid_send(hdev, msg);
584
585 t = wait_for_completion_timeout(x: &par->wait, VSP_TIMEOUT);
586 if (!t) {
587 pr_err("Time out on waiting resolution response\n");
588 ret = -ETIMEDOUT;
589 goto out;
590 }
591
592 if (msg->resolution_resp.resolution_count == 0) {
593 pr_err("No supported resolutions\n");
594 ret = -ENODEV;
595 goto out;
596 }
597
598 index = msg->resolution_resp.default_resolution_index;
599 if (index >= msg->resolution_resp.resolution_count) {
600 pr_err("Invalid resolution index: %d\n", index);
601 ret = -ENODEV;
602 goto out;
603 }
604
605 screen_width =
606 msg->resolution_resp.supported_resolution[index].width;
607 screen_height =
608 msg->resolution_resp.supported_resolution[index].height;
609
610out:
611 return ret;
612}
613
614/* Connect to VSP (Virtual Service Provider) on host */
615static int synthvid_connect_vsp(struct hv_device *hdev)
616{
617 struct fb_info *info = hv_get_drvdata(dev: hdev);
618 struct hvfb_par *par = info->par;
619 int ret;
620
621 ret = vmbus_open(channel: hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
622 NULL, userdatalen: 0, onchannel_callback: synthvid_receive, context: hdev);
623 if (ret) {
624 pr_err("Unable to open vmbus channel\n");
625 return ret;
626 }
627
628 /* Negotiate the protocol version with host */
629 switch (vmbus_proto_version) {
630 case VERSION_WIN10:
631 case VERSION_WIN10_V5:
632 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
633 if (!ret)
634 break;
635 fallthrough;
636 case VERSION_WIN8:
637 case VERSION_WIN8_1:
638 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
639 break;
640 default:
641 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
642 break;
643 }
644
645 if (ret) {
646 pr_err("Synthetic video device version not accepted\n");
647 goto error;
648 }
649
650 screen_depth = SYNTHVID_DEPTH_WIN8;
651 if (synthvid_ver_ge(ver1: par->synthvid_version, SYNTHVID_VERSION_WIN10)) {
652 ret = synthvid_get_supported_resolution(hdev);
653 if (ret)
654 pr_info("Failed to get supported resolution from host, use default\n");
655 }
656
657 screen_fb_size = hdev->channel->offermsg.offer.
658 mmio_megabytes * 1024 * 1024;
659
660 return 0;
661
662error:
663 vmbus_close(channel: hdev->channel);
664 return ret;
665}
666
667/* Send VRAM and Situation messages to the host */
668static int synthvid_send_config(struct hv_device *hdev)
669{
670 struct fb_info *info = hv_get_drvdata(dev: hdev);
671 struct hvfb_par *par = info->par;
672 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
673 int ret = 0;
674 unsigned long t;
675
676 /* Send VRAM location */
677 memset(msg, 0, sizeof(struct synthvid_msg));
678 msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
679 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
680 sizeof(struct synthvid_vram_location);
681 msg->vram.user_ctx = msg->vram.vram_gpa = par->mmio_pp;
682 msg->vram.is_vram_gpa_specified = 1;
683 synthvid_send(hdev, msg);
684
685 t = wait_for_completion_timeout(x: &par->wait, VSP_TIMEOUT);
686 if (!t) {
687 pr_err("Time out on waiting vram location ack\n");
688 ret = -ETIMEDOUT;
689 goto out;
690 }
691 if (msg->vram_ack.user_ctx != par->mmio_pp) {
692 pr_err("Unable to set VRAM location\n");
693 ret = -ENODEV;
694 goto out;
695 }
696
697 /* Send pointer and situation update */
698 synthvid_send_ptr(hdev);
699 synthvid_send_situ(hdev);
700
701out:
702 return ret;
703}
704
705
706/*
707 * Delayed work callback:
708 * It is scheduled to call whenever update request is received and it has
709 * not been called in last HVFB_ONDEMAND_THROTTLE time interval.
710 */
711static void hvfb_update_work(struct work_struct *w)
712{
713 struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
714 struct fb_info *info = par->info;
715 unsigned long flags;
716 int x1, x2, y1, y2;
717 int j;
718
719 spin_lock_irqsave(&par->delayed_refresh_lock, flags);
720 /* Reset the request flag */
721 par->delayed_refresh = false;
722
723 /* Store the dirty rectangle to local variables */
724 x1 = par->x1;
725 x2 = par->x2;
726 y1 = par->y1;
727 y2 = par->y2;
728
729 /* Clear dirty rectangle */
730 par->x1 = par->y1 = INT_MAX;
731 par->x2 = par->y2 = 0;
732
733 spin_unlock_irqrestore(lock: &par->delayed_refresh_lock, flags);
734
735 if (x1 > info->var.xres || x2 > info->var.xres ||
736 y1 > info->var.yres || y2 > info->var.yres || x2 <= x1)
737 return;
738
739 /* Copy the dirty rectangle to frame buffer memory */
740 if (par->need_docopy)
741 for (j = y1; j < y2; j++)
742 hvfb_docopy(par,
743 offset: j * info->fix.line_length +
744 (x1 * screen_depth / 8),
745 size: (x2 - x1) * screen_depth / 8);
746
747 /* Refresh */
748 if (par->fb_ready && par->update)
749 synthvid_update(info, x1, y1, x2, y2);
750}
751
752/*
753 * Control the on-demand refresh frequency. It schedules a delayed
754 * screen update if it has not yet.
755 */
756static void hvfb_ondemand_refresh_throttle(struct hvfb_par *par,
757 int x1, int y1, int w, int h)
758{
759 unsigned long flags;
760 int x2 = x1 + w;
761 int y2 = y1 + h;
762
763 spin_lock_irqsave(&par->delayed_refresh_lock, flags);
764
765 /* Merge dirty rectangle */
766 par->x1 = min_t(int, par->x1, x1);
767 par->y1 = min_t(int, par->y1, y1);
768 par->x2 = max_t(int, par->x2, x2);
769 par->y2 = max_t(int, par->y2, y2);
770
771 /* Schedule a delayed screen update if not yet */
772 if (par->delayed_refresh == false) {
773 schedule_delayed_work(dwork: &par->dwork,
774 HVFB_ONDEMAND_THROTTLE);
775 par->delayed_refresh = true;
776 }
777
778 spin_unlock_irqrestore(lock: &par->delayed_refresh_lock, flags);
779}
780
781static int hvfb_on_panic(struct notifier_block *nb,
782 unsigned long e, void *p)
783{
784 struct hv_device *hdev;
785 struct hvfb_par *par;
786 struct fb_info *info;
787
788 par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
789 info = par->info;
790 hdev = device_to_hv_device(info->device);
791
792 if (hv_ringbuffer_spinlock_busy(channel: hdev->channel))
793 return NOTIFY_DONE;
794
795 par->synchronous_fb = true;
796 if (par->need_docopy)
797 hvfb_docopy(par, offset: 0, size: dio_fb_size);
798 synthvid_update(info, x1: 0, y1: 0, INT_MAX, INT_MAX);
799
800 return NOTIFY_DONE;
801}
802
803/* Framebuffer operation handlers */
804
805static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
806{
807 if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
808 var->xres > screen_width || var->yres > screen_height ||
809 var->bits_per_pixel != screen_depth)
810 return -EINVAL;
811
812 var->xres_virtual = var->xres;
813 var->yres_virtual = var->yres;
814
815 return 0;
816}
817
818static int hvfb_set_par(struct fb_info *info)
819{
820 struct hv_device *hdev = device_to_hv_device(info->device);
821
822 return synthvid_send_situ(hdev);
823}
824
825
826static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
827{
828 return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
829}
830
831static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
832 unsigned blue, unsigned transp, struct fb_info *info)
833{
834 u32 *pal = info->pseudo_palette;
835
836 if (regno > 15)
837 return -EINVAL;
838
839 pal[regno] = chan_to_field(chan: red, bf: &info->var.red)
840 | chan_to_field(chan: green, bf: &info->var.green)
841 | chan_to_field(chan: blue, bf: &info->var.blue)
842 | chan_to_field(chan: transp, bf: &info->var.transp);
843
844 return 0;
845}
846
847static int hvfb_blank(int blank, struct fb_info *info)
848{
849 return 1; /* get fb_blank to set the colormap to all black */
850}
851
852static void hvfb_ops_damage_range(struct fb_info *info, off_t off, size_t len)
853{
854 /* TODO: implement damage handling */
855}
856
857static void hvfb_ops_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height)
858{
859 struct hvfb_par *par = info->par;
860
861 if (par->synchronous_fb)
862 synthvid_update(info, x1: 0, y1: 0, INT_MAX, INT_MAX);
863 else
864 hvfb_ondemand_refresh_throttle(par, x1: x, y1: y, w: width, h: height);
865}
866
867/*
868 * fb_ops.fb_destroy is called by the last put_fb_info() call at the end
869 * of unregister_framebuffer() or fb_release(). Do any cleanup related to
870 * framebuffer here.
871 */
872static void hvfb_destroy(struct fb_info *info)
873{
874 hvfb_putmem(info);
875 framebuffer_release(info);
876}
877
878/*
879 * TODO: GEN1 codepaths allocate from system or DMA-able memory. Fix the
880 * driver to use the _SYSMEM_ or _DMAMEM_ helpers in these cases.
881 */
882FB_GEN_DEFAULT_DEFERRED_IOMEM_OPS(hvfb_ops,
883 hvfb_ops_damage_range,
884 hvfb_ops_damage_area)
885
886static const struct fb_ops hvfb_ops = {
887 .owner = THIS_MODULE,
888 FB_DEFAULT_DEFERRED_OPS(hvfb_ops),
889 .fb_check_var = hvfb_check_var,
890 .fb_set_par = hvfb_set_par,
891 .fb_setcolreg = hvfb_setcolreg,
892 .fb_blank = hvfb_blank,
893 .fb_destroy = hvfb_destroy,
894};
895
896/* Get options from kernel paramenter "video=" */
897static void hvfb_get_option(struct fb_info *info)
898{
899 struct hvfb_par *par = info->par;
900 char *opt = NULL, *p;
901 uint x = 0, y = 0;
902
903 if (fb_get_options(KBUILD_MODNAME, option: &opt) || !opt || !*opt)
904 return;
905
906 p = strsep(&opt, "x");
907 if (!*p || kstrtouint(s: p, base: 0, res: &x) ||
908 !opt || !*opt || kstrtouint(s: opt, base: 0, res: &y)) {
909 pr_err("Screen option is invalid: skipped\n");
910 return;
911 }
912
913 if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
914 (synthvid_ver_ge(ver1: par->synthvid_version, SYNTHVID_VERSION_WIN10) &&
915 (x * y * screen_depth / 8 > screen_fb_size)) ||
916 (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
917 x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8)) {
918 pr_err("Screen resolution option is out of range: skipped\n");
919 return;
920 }
921
922 screen_width = x;
923 screen_height = y;
924 return;
925}
926
927/*
928 * Allocate enough contiguous physical memory.
929 * Return physical address if succeeded or -1 if failed.
930 */
931static phys_addr_t hvfb_get_phymem(struct hv_device *hdev,
932 unsigned int request_size)
933{
934 struct page *page = NULL;
935 dma_addr_t dma_handle;
936 void *vmem;
937 phys_addr_t paddr = 0;
938 unsigned int order = get_order(size: request_size);
939
940 if (request_size == 0)
941 return -1;
942
943 if (order <= MAX_PAGE_ORDER) {
944 /* Call alloc_pages if the size is less than 2^MAX_PAGE_ORDER */
945 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
946 if (!page)
947 return -1;
948
949 paddr = (page_to_pfn(page) << PAGE_SHIFT);
950 } else {
951 /* Allocate from CMA */
952 hdev->device.coherent_dma_mask = DMA_BIT_MASK(64);
953
954 vmem = dma_alloc_coherent(dev: &hdev->device,
955 round_up(request_size, PAGE_SIZE),
956 dma_handle: &dma_handle,
957 GFP_KERNEL | __GFP_NOWARN);
958
959 if (!vmem)
960 return -1;
961
962 paddr = virt_to_phys(address: vmem);
963 }
964
965 return paddr;
966}
967
968/* Release contiguous physical memory */
969static void hvfb_release_phymem(struct device *device,
970 phys_addr_t paddr, unsigned int size)
971{
972 unsigned int order = get_order(size);
973
974 if (order <= MAX_PAGE_ORDER)
975 __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order);
976 else
977 dma_free_coherent(dev: device,
978 round_up(size, PAGE_SIZE),
979 phys_to_virt(address: paddr),
980 dma_handle: paddr);
981}
982
983
984/* Get framebuffer memory from Hyper-V video pci space */
985static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
986{
987 struct hvfb_par *par = info->par;
988 struct pci_dev *pdev = NULL;
989 void __iomem *fb_virt;
990 int gen2vm = efi_enabled(EFI_BOOT);
991 resource_size_t base = 0;
992 resource_size_t size = 0;
993 phys_addr_t paddr;
994 int ret;
995
996 if (!gen2vm) {
997 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
998 PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
999 if (!pdev) {
1000 pr_err("Unable to find PCI Hyper-V video\n");
1001 return -ENODEV;
1002 }
1003
1004 base = pci_resource_start(pdev, 0);
1005 size = pci_resource_len(pdev, 0);
1006 aperture_remove_conflicting_devices(base, size, KBUILD_MODNAME);
1007
1008 /*
1009 * For Gen 1 VM, we can directly use the contiguous memory
1010 * from VM. If we succeed, deferred IO happens directly
1011 * on this allocated framebuffer memory, avoiding extra
1012 * memory copy.
1013 */
1014 paddr = hvfb_get_phymem(hdev, request_size: screen_fb_size);
1015 if (paddr != (phys_addr_t) -1) {
1016 par->mmio_pp = paddr;
1017 par->mmio_vp = par->dio_vp = __va(paddr);
1018
1019 info->fix.smem_start = paddr;
1020 info->fix.smem_len = screen_fb_size;
1021 info->screen_base = par->mmio_vp;
1022 info->screen_size = screen_fb_size;
1023
1024 par->need_docopy = false;
1025 goto getmem_done;
1026 }
1027 pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n");
1028 } else {
1029 aperture_remove_all_conflicting_devices(KBUILD_MODNAME);
1030 }
1031
1032 /*
1033 * Cannot use contiguous physical memory, so allocate MMIO space for
1034 * the framebuffer. At this point in the function, conflicting devices
1035 * that might have claimed the framebuffer MMIO space based on
1036 * screen_info.lfb_base must have already been removed so that
1037 * vmbus_allocate_mmio() does not allocate different MMIO space. If the
1038 * kdump image were to be loaded using kexec_file_load(), the
1039 * framebuffer location in the kdump image would be set from
1040 * screen_info.lfb_base at the time that kdump is enabled. If the
1041 * framebuffer has moved elsewhere, this could be the wrong location,
1042 * causing kdump to hang when efifb (for example) loads.
1043 */
1044 dio_fb_size =
1045 screen_width * screen_height * screen_depth / 8;
1046
1047 ret = vmbus_allocate_mmio(new: &par->mem, device_obj: hdev, min: 0, max: -1,
1048 size: screen_fb_size, align: 0x100000, fb_overlap_ok: true);
1049 if (ret != 0) {
1050 pr_err("Unable to allocate framebuffer memory\n");
1051 goto err1;
1052 }
1053
1054 /*
1055 * Map the VRAM cacheable for performance. This is also required for
1056 * VM Connect to display properly for ARM64 Linux VM, as the host also
1057 * maps the VRAM cacheable.
1058 */
1059 fb_virt = ioremap_cache(offset: par->mem->start, size: screen_fb_size);
1060 if (!fb_virt)
1061 goto err2;
1062
1063 /* Allocate memory for deferred IO */
1064 par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE));
1065 if (par->dio_vp == NULL)
1066 goto err3;
1067
1068 /* Physical address of FB device */
1069 par->mmio_pp = par->mem->start;
1070 /* Virtual address of FB device */
1071 par->mmio_vp = (unsigned char *) fb_virt;
1072
1073 info->fix.smem_start = par->mem->start;
1074 info->fix.smem_len = dio_fb_size;
1075 info->screen_base = par->dio_vp;
1076 info->screen_size = dio_fb_size;
1077
1078getmem_done:
1079 if (!gen2vm)
1080 pci_dev_put(dev: pdev);
1081
1082 return 0;
1083
1084err3:
1085 iounmap(addr: fb_virt);
1086err2:
1087 vmbus_free_mmio(start: par->mem->start, size: screen_fb_size);
1088 par->mem = NULL;
1089err1:
1090 if (!gen2vm)
1091 pci_dev_put(dev: pdev);
1092
1093 return -ENOMEM;
1094}
1095
1096/* Release the framebuffer */
1097static void hvfb_putmem(struct fb_info *info)
1098{
1099 struct hvfb_par *par = info->par;
1100
1101 if (par->need_docopy) {
1102 vfree(addr: par->dio_vp);
1103 iounmap(addr: par->mmio_vp);
1104 vmbus_free_mmio(start: par->mem->start, size: screen_fb_size);
1105 } else {
1106 hvfb_release_phymem(device: info->device, paddr: info->fix.smem_start,
1107 size: screen_fb_size);
1108 }
1109
1110 par->mem = NULL;
1111}
1112
1113
1114static int hvfb_probe(struct hv_device *hdev,
1115 const struct hv_vmbus_device_id *dev_id)
1116{
1117 struct fb_info *info;
1118 struct hvfb_par *par;
1119 int ret;
1120
1121 info = framebuffer_alloc(size: sizeof(struct hvfb_par), dev: &hdev->device);
1122 if (!info)
1123 return -ENOMEM;
1124
1125 par = info->par;
1126 par->info = info;
1127 par->fb_ready = false;
1128 par->need_docopy = true;
1129 init_completion(x: &par->wait);
1130 INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
1131
1132 par->delayed_refresh = false;
1133 spin_lock_init(&par->delayed_refresh_lock);
1134 par->x1 = par->y1 = INT_MAX;
1135 par->x2 = par->y2 = 0;
1136
1137 /* Connect to VSP */
1138 hv_set_drvdata(dev: hdev, data: info);
1139 ret = synthvid_connect_vsp(hdev);
1140 if (ret) {
1141 pr_err("Unable to connect to VSP\n");
1142 goto error1;
1143 }
1144
1145 hvfb_get_option(info);
1146 pr_info("Screen resolution: %dx%d, Color depth: %d, Frame buffer size: %d\n",
1147 screen_width, screen_height, screen_depth, screen_fb_size);
1148
1149 ret = hvfb_getmem(hdev, info);
1150 if (ret) {
1151 pr_err("No memory for framebuffer\n");
1152 goto error2;
1153 }
1154
1155 /* Set up fb_info */
1156 info->var.xres_virtual = info->var.xres = screen_width;
1157 info->var.yres_virtual = info->var.yres = screen_height;
1158 info->var.bits_per_pixel = screen_depth;
1159
1160 if (info->var.bits_per_pixel == 16) {
1161 info->var.red = (struct fb_bitfield){11, 5, 0};
1162 info->var.green = (struct fb_bitfield){5, 6, 0};
1163 info->var.blue = (struct fb_bitfield){0, 5, 0};
1164 info->var.transp = (struct fb_bitfield){0, 0, 0};
1165 } else {
1166 info->var.red = (struct fb_bitfield){16, 8, 0};
1167 info->var.green = (struct fb_bitfield){8, 8, 0};
1168 info->var.blue = (struct fb_bitfield){0, 8, 0};
1169 info->var.transp = (struct fb_bitfield){24, 8, 0};
1170 }
1171
1172 info->var.activate = FB_ACTIVATE_NOW;
1173 info->var.height = -1;
1174 info->var.width = -1;
1175 info->var.vmode = FB_VMODE_NONINTERLACED;
1176
1177 strcpy(p: info->fix.id, KBUILD_MODNAME);
1178 info->fix.type = FB_TYPE_PACKED_PIXELS;
1179 info->fix.visual = FB_VISUAL_TRUECOLOR;
1180 info->fix.line_length = screen_width * screen_depth / 8;
1181 info->fix.accel = FB_ACCEL_NONE;
1182
1183 info->fbops = &hvfb_ops;
1184 info->pseudo_palette = par->pseudo_palette;
1185
1186 /* Initialize deferred IO */
1187 info->fbdefio = &synthvid_defio;
1188 fb_deferred_io_init(info);
1189
1190 /* Send config to host */
1191 ret = synthvid_send_config(hdev);
1192 if (ret)
1193 goto error;
1194
1195 ret = devm_register_framebuffer(dev: &hdev->device, fb_info: info);
1196 if (ret) {
1197 pr_err("Unable to register framebuffer\n");
1198 goto error;
1199 }
1200
1201 par->fb_ready = true;
1202
1203 par->synchronous_fb = false;
1204
1205 /*
1206 * We need to be sure this panic notifier runs _before_ the
1207 * vmbus disconnect, so order it by priority. It must execute
1208 * before the function hv_panic_vmbus_unload() [drivers/hv/vmbus_drv.c],
1209 * which is almost at the end of list, with priority = INT_MIN + 1.
1210 */
1211 par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
1212 par->hvfb_panic_nb.priority = INT_MIN + 10;
1213 atomic_notifier_chain_register(nh: &panic_notifier_list,
1214 nb: &par->hvfb_panic_nb);
1215
1216 return 0;
1217
1218error:
1219 fb_deferred_io_cleanup(info);
1220 hvfb_putmem(info);
1221error2:
1222 vmbus_close(channel: hdev->channel);
1223error1:
1224 cancel_delayed_work_sync(dwork: &par->dwork);
1225 hv_set_drvdata(dev: hdev, NULL);
1226 framebuffer_release(info);
1227 return ret;
1228}
1229
1230static void hvfb_remove(struct hv_device *hdev)
1231{
1232 struct fb_info *info = hv_get_drvdata(dev: hdev);
1233 struct hvfb_par *par = info->par;
1234
1235 atomic_notifier_chain_unregister(nh: &panic_notifier_list,
1236 nb: &par->hvfb_panic_nb);
1237
1238 par->update = false;
1239 par->fb_ready = false;
1240
1241 fb_deferred_io_cleanup(info);
1242
1243 cancel_delayed_work_sync(dwork: &par->dwork);
1244
1245 vmbus_close(channel: hdev->channel);
1246 hv_set_drvdata(dev: hdev, NULL);
1247}
1248
1249static int hvfb_suspend(struct hv_device *hdev)
1250{
1251 struct fb_info *info = hv_get_drvdata(dev: hdev);
1252 struct hvfb_par *par = info->par;
1253
1254 console_lock();
1255
1256 /* 1 means do suspend */
1257 fb_set_suspend(info, state: 1);
1258
1259 cancel_delayed_work_sync(dwork: &par->dwork);
1260 cancel_delayed_work_sync(dwork: &info->deferred_work);
1261
1262 par->update_saved = par->update;
1263 par->update = false;
1264 par->fb_ready = false;
1265
1266 vmbus_close(channel: hdev->channel);
1267
1268 console_unlock();
1269
1270 return 0;
1271}
1272
1273static int hvfb_resume(struct hv_device *hdev)
1274{
1275 struct fb_info *info = hv_get_drvdata(dev: hdev);
1276 struct hvfb_par *par = info->par;
1277 int ret;
1278
1279 console_lock();
1280
1281 ret = synthvid_connect_vsp(hdev);
1282 if (ret != 0)
1283 goto out;
1284
1285 ret = synthvid_send_config(hdev);
1286 if (ret != 0) {
1287 vmbus_close(channel: hdev->channel);
1288 goto out;
1289 }
1290
1291 par->fb_ready = true;
1292 par->update = par->update_saved;
1293
1294 schedule_delayed_work(dwork: &info->deferred_work, delay: info->fbdefio->delay);
1295 schedule_delayed_work(dwork: &par->dwork, HVFB_UPDATE_DELAY);
1296
1297 /* 0 means do resume */
1298 fb_set_suspend(info, state: 0);
1299
1300out:
1301 console_unlock();
1302
1303 return ret;
1304}
1305
1306
1307static const struct pci_device_id pci_stub_id_table[] = {
1308 {
1309 .vendor = PCI_VENDOR_ID_MICROSOFT,
1310 .device = PCI_DEVICE_ID_HYPERV_VIDEO,
1311 },
1312 { /* end of list */ }
1313};
1314
1315static const struct hv_vmbus_device_id id_table[] = {
1316 /* Synthetic Video Device GUID */
1317 {HV_SYNTHVID_GUID},
1318 {}
1319};
1320
1321MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
1322MODULE_DEVICE_TABLE(vmbus, id_table);
1323
1324static struct hv_driver hvfb_drv = {
1325 .name = KBUILD_MODNAME,
1326 .id_table = id_table,
1327 .probe = hvfb_probe,
1328 .remove = hvfb_remove,
1329 .suspend = hvfb_suspend,
1330 .resume = hvfb_resume,
1331 .driver = {
1332 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1333 },
1334};
1335
1336static int hvfb_pci_stub_probe(struct pci_dev *pdev,
1337 const struct pci_device_id *ent)
1338{
1339 return 0;
1340}
1341
1342static void hvfb_pci_stub_remove(struct pci_dev *pdev)
1343{
1344}
1345
1346static struct pci_driver hvfb_pci_stub_driver = {
1347 .name = KBUILD_MODNAME,
1348 .id_table = pci_stub_id_table,
1349 .probe = hvfb_pci_stub_probe,
1350 .remove = hvfb_pci_stub_remove,
1351 .driver = {
1352 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1353 }
1354};
1355
1356static int __init hvfb_drv_init(void)
1357{
1358 int ret;
1359
1360 pr_warn("Deprecated: use Hyper-V DRM driver instead\n");
1361
1362 if (fb_modesetting_disabled(drvname: "hyper_fb"))
1363 return -ENODEV;
1364
1365 ret = vmbus_driver_register(&hvfb_drv);
1366 if (ret != 0)
1367 return ret;
1368
1369 ret = pci_register_driver(&hvfb_pci_stub_driver);
1370 if (ret != 0) {
1371 vmbus_driver_unregister(hv_driver: &hvfb_drv);
1372 return ret;
1373 }
1374
1375 return 0;
1376}
1377
1378static void __exit hvfb_drv_exit(void)
1379{
1380 pci_unregister_driver(dev: &hvfb_pci_stub_driver);
1381 vmbus_driver_unregister(hv_driver: &hvfb_drv);
1382}
1383
1384module_init(hvfb_drv_init);
1385module_exit(hvfb_drv_exit);
1386
1387MODULE_LICENSE("GPL");
1388MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");
1389

source code of linux/drivers/video/fbdev/hyperv_fb.c