1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2012, Microsoft Corporation.
10 * Hyper-V Synthetic Video Frame Buffer Driver
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
17 * It also solves the double mouse cursor issue of the emulated video mode.
19 * The default screen resolution is 1152x864, which may be changed by a
21 * video=hyperv_fb:<width>x<height>
22 * For example: video=hyperv_fb:1280x1024
24 * Portrait orientation is also supported:
25 * For example: video=hyperv_fb:864x1152
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
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:
41 * This gives 130MB memory to CMA allocator that can be allocated to
42 * framebuffer. For reference, 8K resolution (7680x4320) takes about
46 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
48 #include <linux/module.h>
49 #include <linux/kernel.h>
50 #include <linux/vmalloc.h>
51 #include <linux/init.h>
52 #include <linux/completion.h>
54 #include <linux/pci.h>
55 #include <linux/efi.h>
56 #include <linux/console.h>
58 #include <linux/hyperv.h>
61 /* Hyper-V Synthetic Video Protocol definitions and structures */
62 #define MAX_VMBUS_PKT_SIZE 0x4000
64 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
65 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
66 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
67 #define SYNTHVID_VERSION_WIN10 SYNTHVID_VERSION(3, 5)
69 #define SYNTHVID_VER_GET_MAJOR(ver) (ver & 0x0000ffff)
70 #define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16)
72 #define SYNTHVID_DEPTH_WIN7 16
73 #define SYNTHVID_DEPTH_WIN8 32
75 #define SYNTHVID_FB_SIZE_WIN7 (4 * 1024 * 1024)
76 #define SYNTHVID_WIDTH_MAX_WIN7 1600
77 #define SYNTHVID_HEIGHT_MAX_WIN7 1200
79 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
81 #define PCI_VENDOR_ID_MICROSOFT 0x1414
82 #define PCI_DEVICE_ID_HYPERV_VIDEO 0x5353
93 u32 size; /* size of message after this field */
97 enum synthvid_msg_type {
99 SYNTHVID_VERSION_REQUEST = 1,
100 SYNTHVID_VERSION_RESPONSE = 2,
101 SYNTHVID_VRAM_LOCATION = 3,
102 SYNTHVID_VRAM_LOCATION_ACK = 4,
103 SYNTHVID_SITUATION_UPDATE = 5,
104 SYNTHVID_SITUATION_UPDATE_ACK = 6,
105 SYNTHVID_POINTER_POSITION = 7,
106 SYNTHVID_POINTER_SHAPE = 8,
107 SYNTHVID_FEATURE_CHANGE = 9,
109 SYNTHVID_RESOLUTION_REQUEST = 13,
110 SYNTHVID_RESOLUTION_RESPONSE = 14,
115 #define SYNTHVID_EDID_BLOCK_SIZE 128
116 #define SYNTHVID_MAX_RESOLUTION_COUNT 64
118 struct hvd_screen_info {
123 struct synthvid_msg_hdr {
125 u32 size; /* size of this header + payload after this field*/
128 struct synthvid_version_req {
132 struct synthvid_version_resp {
135 u8 max_video_outputs;
138 struct synthvid_supported_resolution_req {
139 u8 maximum_resolution_count;
142 struct synthvid_supported_resolution_resp {
143 u8 edid_block[SYNTHVID_EDID_BLOCK_SIZE];
145 u8 default_resolution_index;
147 struct hvd_screen_info
148 supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT];
151 struct synthvid_vram_location {
153 u8 is_vram_gpa_specified;
157 struct synthvid_vram_location_ack {
161 struct video_output_situation {
170 struct synthvid_situation_update {
172 u8 video_output_count;
173 struct video_output_situation video_output[1];
176 struct synthvid_situation_update_ack {
180 struct synthvid_pointer_position {
188 #define CURSOR_MAX_X 96
189 #define CURSOR_MAX_Y 96
190 #define CURSOR_ARGB_PIXEL_SIZE 4
191 #define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE)
192 #define CURSOR_COMPLETE (-1)
194 struct synthvid_pointer_shape {
197 u32 width; /* CURSOR_MAX_X at most */
198 u32 height; /* CURSOR_MAX_Y at most */
199 u32 hot_x; /* hotspot relative to upper-left of pointer image */
204 struct synthvid_feature_change {
206 u8 is_ptr_pos_needed;
207 u8 is_ptr_shape_needed;
212 s32 x1, y1; /* top left corner */
213 s32 x2, y2; /* bottom right corner, exclusive */
216 struct synthvid_dirt {
222 struct synthvid_msg {
223 struct pipe_msg_hdr pipe_hdr;
224 struct synthvid_msg_hdr vid_hdr;
226 struct synthvid_version_req ver_req;
227 struct synthvid_version_resp ver_resp;
228 struct synthvid_vram_location vram;
229 struct synthvid_vram_location_ack vram_ack;
230 struct synthvid_situation_update situ;
231 struct synthvid_situation_update_ack situ_ack;
232 struct synthvid_pointer_position ptr_pos;
233 struct synthvid_pointer_shape ptr_shape;
234 struct synthvid_feature_change feature_chg;
235 struct synthvid_dirt dirt;
236 struct synthvid_supported_resolution_req resolution_req;
237 struct synthvid_supported_resolution_resp resolution_resp;
242 /* FB driver definitions and structures */
243 #define HVFB_WIDTH 1152 /* default screen width */
244 #define HVFB_HEIGHT 864 /* default screen height */
245 #define HVFB_WIDTH_MIN 640
246 #define HVFB_HEIGHT_MIN 480
248 #define RING_BUFSIZE (256 * 1024)
249 #define VSP_TIMEOUT (10 * HZ)
250 #define HVFB_UPDATE_DELAY (HZ / 20)
251 #define HVFB_ONDEMAND_THROTTLE (HZ / 20)
254 struct fb_info *info;
255 struct resource *mem;
256 bool fb_ready; /* fb device is ready */
257 struct completion wait;
258 u32 synthvid_version;
260 struct delayed_work dwork;
262 bool update_saved; /* The value of 'update' before hibernation */
264 u32 pseudo_palette[16];
265 u8 init_buf[MAX_VMBUS_PKT_SIZE];
266 u8 recv_buf[MAX_VMBUS_PKT_SIZE];
268 /* If true, the VSC notifies the VSP on every framebuffer change */
271 /* If true, need to copy from deferred IO mem to framebuffer mem */
274 struct notifier_block hvfb_panic_nb;
276 /* Memory for deferred IO and frame buffer itself */
277 unsigned char *dio_vp;
278 unsigned char *mmio_vp;
281 /* Dirty rectangle, protected by delayed_refresh_lock */
283 bool delayed_refresh;
284 spinlock_t delayed_refresh_lock;
287 static uint screen_width = HVFB_WIDTH;
288 static uint screen_height = HVFB_HEIGHT;
289 static uint screen_width_max = HVFB_WIDTH;
290 static uint screen_height_max = HVFB_HEIGHT;
291 static uint screen_depth;
292 static uint screen_fb_size;
293 static uint dio_fb_size; /* FB size for deferred IO */
295 /* Send message to Hyper-V host */
296 static inline int synthvid_send(struct hv_device *hdev,
297 struct synthvid_msg *msg)
299 static atomic64_t request_id = ATOMIC64_INIT(0);
302 msg->pipe_hdr.type = PIPE_MSG_DATA;
303 msg->pipe_hdr.size = msg->vid_hdr.size;
305 ret = vmbus_sendpacket(hdev->channel, msg,
306 msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
307 atomic64_inc_return(&request_id),
308 VM_PKT_DATA_INBAND, 0);
311 pr_err("Unable to send packet via vmbus\n");
317 /* Send screen resolution info to host */
318 static int synthvid_send_situ(struct hv_device *hdev)
320 struct fb_info *info = hv_get_drvdata(hdev);
321 struct synthvid_msg msg;
326 memset(&msg, 0, sizeof(struct synthvid_msg));
328 msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
329 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
330 sizeof(struct synthvid_situation_update);
331 msg.situ.user_ctx = 0;
332 msg.situ.video_output_count = 1;
333 msg.situ.video_output[0].active = 1;
334 msg.situ.video_output[0].vram_offset = 0;
335 msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
336 msg.situ.video_output[0].width_pixels = info->var.xres;
337 msg.situ.video_output[0].height_pixels = info->var.yres;
338 msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
340 synthvid_send(hdev, &msg);
345 /* Send mouse pointer info to host */
346 static int synthvid_send_ptr(struct hv_device *hdev)
348 struct synthvid_msg msg;
350 memset(&msg, 0, sizeof(struct synthvid_msg));
351 msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
352 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
353 sizeof(struct synthvid_pointer_position);
354 msg.ptr_pos.is_visible = 1;
355 msg.ptr_pos.video_output = 0;
356 msg.ptr_pos.image_x = 0;
357 msg.ptr_pos.image_y = 0;
358 synthvid_send(hdev, &msg);
360 memset(&msg, 0, sizeof(struct synthvid_msg));
361 msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
362 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
363 sizeof(struct synthvid_pointer_shape);
364 msg.ptr_shape.part_idx = CURSOR_COMPLETE;
365 msg.ptr_shape.is_argb = 1;
366 msg.ptr_shape.width = 1;
367 msg.ptr_shape.height = 1;
368 msg.ptr_shape.hot_x = 0;
369 msg.ptr_shape.hot_y = 0;
370 msg.ptr_shape.data[0] = 0;
371 msg.ptr_shape.data[1] = 1;
372 msg.ptr_shape.data[2] = 1;
373 msg.ptr_shape.data[3] = 1;
374 synthvid_send(hdev, &msg);
379 /* Send updated screen area (dirty rectangle) location to host */
381 synthvid_update(struct fb_info *info, int x1, int y1, int x2, int y2)
383 struct hv_device *hdev = device_to_hv_device(info->device);
384 struct synthvid_msg msg;
386 memset(&msg, 0, sizeof(struct synthvid_msg));
392 msg.vid_hdr.type = SYNTHVID_DIRT;
393 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
394 sizeof(struct synthvid_dirt);
395 msg.dirt.video_output = 0;
396 msg.dirt.dirt_count = 1;
397 msg.dirt.rect[0].x1 = (x1 > x2) ? 0 : x1;
398 msg.dirt.rect[0].y1 = (y1 > y2) ? 0 : y1;
399 msg.dirt.rect[0].x2 =
400 (x2 < x1 || x2 > info->var.xres) ? info->var.xres : x2;
401 msg.dirt.rect[0].y2 =
402 (y2 < y1 || y2 > info->var.yres) ? info->var.yres : y2;
404 synthvid_send(hdev, &msg);
409 static void hvfb_docopy(struct hvfb_par *par,
410 unsigned long offset,
413 if (!par || !par->mmio_vp || !par->dio_vp || !par->fb_ready ||
414 size == 0 || offset >= dio_fb_size)
417 if (offset + size > dio_fb_size)
418 size = dio_fb_size - offset;
420 memcpy(par->mmio_vp + offset, par->dio_vp + offset, size);
423 /* Deferred IO callback */
424 static void synthvid_deferred_io(struct fb_info *p,
425 struct list_head *pagelist)
427 struct hvfb_par *par = p->par;
429 unsigned long start, end;
430 int y1, y2, miny, maxy;
436 * Merge dirty pages. It is possible that last page cross
437 * over the end of frame buffer row yres. This is taken care of
438 * in synthvid_update function by clamping the y2
441 list_for_each_entry(page, pagelist, lru) {
442 start = page->index << PAGE_SHIFT;
443 end = start + PAGE_SIZE - 1;
444 y1 = start / p->fix.line_length;
445 y2 = end / p->fix.line_length;
446 miny = min_t(int, miny, y1);
447 maxy = max_t(int, maxy, y2);
449 /* Copy from dio space to mmio address */
450 if (par->fb_ready && par->need_docopy)
451 hvfb_docopy(par, start, PAGE_SIZE);
454 if (par->fb_ready && par->update)
455 synthvid_update(p, 0, miny, p->var.xres, maxy + 1);
458 static struct fb_deferred_io synthvid_defio = {
460 .deferred_io = synthvid_deferred_io,
464 * Actions on received messages from host:
465 * Complete the wait event.
466 * Or, reply with screen and cursor info.
468 static void synthvid_recv_sub(struct hv_device *hdev)
470 struct fb_info *info = hv_get_drvdata(hdev);
471 struct hvfb_par *par;
472 struct synthvid_msg *msg;
478 msg = (struct synthvid_msg *)par->recv_buf;
480 /* Complete the wait event */
481 if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
482 msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE ||
483 msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
484 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
485 complete(&par->wait);
489 /* Reply with screen and cursor info */
490 if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
492 synthvid_send_ptr(hdev);
493 synthvid_send_situ(hdev);
496 par->update = msg->feature_chg.is_dirt_needed;
498 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
502 /* Receive callback for messages from the host */
503 static void synthvid_receive(void *ctx)
505 struct hv_device *hdev = ctx;
506 struct fb_info *info = hv_get_drvdata(hdev);
507 struct hvfb_par *par;
508 struct synthvid_msg *recv_buf;
517 recv_buf = (struct synthvid_msg *)par->recv_buf;
520 ret = vmbus_recvpacket(hdev->channel, recv_buf,
522 &bytes_recvd, &req_id);
523 if (bytes_recvd > 0 &&
524 recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
525 synthvid_recv_sub(hdev);
526 } while (bytes_recvd > 0 && ret == 0);
529 /* Check if the ver1 version is equal or greater than ver2 */
530 static inline bool synthvid_ver_ge(u32 ver1, u32 ver2)
532 if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) ||
533 (SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) &&
534 SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2)))
540 /* Check synthetic video protocol version with the host */
541 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
543 struct fb_info *info = hv_get_drvdata(hdev);
544 struct hvfb_par *par = info->par;
545 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
549 memset(msg, 0, sizeof(struct synthvid_msg));
550 msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
551 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
552 sizeof(struct synthvid_version_req);
553 msg->ver_req.version = ver;
554 synthvid_send(hdev, msg);
556 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
558 pr_err("Time out on waiting version response\n");
562 if (!msg->ver_resp.is_accepted) {
567 par->synthvid_version = ver;
568 pr_info("Synthvid Version major %d, minor %d\n",
569 SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver));
575 /* Get current resolution from the host */
576 static int synthvid_get_supported_resolution(struct hv_device *hdev)
578 struct fb_info *info = hv_get_drvdata(hdev);
579 struct hvfb_par *par = info->par;
580 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
586 memset(msg, 0, sizeof(struct synthvid_msg));
587 msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST;
588 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
589 sizeof(struct synthvid_supported_resolution_req);
591 msg->resolution_req.maximum_resolution_count =
592 SYNTHVID_MAX_RESOLUTION_COUNT;
593 synthvid_send(hdev, msg);
595 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
597 pr_err("Time out on waiting resolution response\n");
602 if (msg->resolution_resp.resolution_count == 0) {
603 pr_err("No supported resolutions\n");
608 index = msg->resolution_resp.default_resolution_index;
609 if (index >= msg->resolution_resp.resolution_count) {
610 pr_err("Invalid resolution index: %d\n", index);
615 for (i = 0; i < msg->resolution_resp.resolution_count; i++) {
616 screen_width_max = max_t(unsigned int, screen_width_max,
617 msg->resolution_resp.supported_resolution[i].width);
618 screen_height_max = max_t(unsigned int, screen_height_max,
619 msg->resolution_resp.supported_resolution[i].height);
623 msg->resolution_resp.supported_resolution[index].width;
625 msg->resolution_resp.supported_resolution[index].height;
631 /* Connect to VSP (Virtual Service Provider) on host */
632 static int synthvid_connect_vsp(struct hv_device *hdev)
634 struct fb_info *info = hv_get_drvdata(hdev);
635 struct hvfb_par *par = info->par;
638 ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
639 NULL, 0, synthvid_receive, hdev);
641 pr_err("Unable to open vmbus channel\n");
645 /* Negotiate the protocol version with host */
646 switch (vmbus_proto_version) {
648 case VERSION_WIN10_V5:
649 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
655 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
661 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN7);
664 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
669 pr_err("Synthetic video device version not accepted\n");
673 if (par->synthvid_version == SYNTHVID_VERSION_WIN7)
674 screen_depth = SYNTHVID_DEPTH_WIN7;
676 screen_depth = SYNTHVID_DEPTH_WIN8;
678 if (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10)) {
679 ret = synthvid_get_supported_resolution(hdev);
681 pr_info("Failed to get supported resolution from host, use default\n");
684 screen_fb_size = hdev->channel->offermsg.offer.
685 mmio_megabytes * 1024 * 1024;
690 vmbus_close(hdev->channel);
694 /* Send VRAM and Situation messages to the host */
695 static int synthvid_send_config(struct hv_device *hdev)
697 struct fb_info *info = hv_get_drvdata(hdev);
698 struct hvfb_par *par = info->par;
699 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
703 /* Send VRAM location */
704 memset(msg, 0, sizeof(struct synthvid_msg));
705 msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
706 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
707 sizeof(struct synthvid_vram_location);
708 msg->vram.user_ctx = msg->vram.vram_gpa = par->mmio_pp;
709 msg->vram.is_vram_gpa_specified = 1;
710 synthvid_send(hdev, msg);
712 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
714 pr_err("Time out on waiting vram location ack\n");
718 if (msg->vram_ack.user_ctx != par->mmio_pp) {
719 pr_err("Unable to set VRAM location\n");
724 /* Send pointer and situation update */
725 synthvid_send_ptr(hdev);
726 synthvid_send_situ(hdev);
734 * Delayed work callback:
735 * It is scheduled to call whenever update request is received and it has
736 * not been called in last HVFB_ONDEMAND_THROTTLE time interval.
738 static void hvfb_update_work(struct work_struct *w)
740 struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
741 struct fb_info *info = par->info;
746 spin_lock_irqsave(&par->delayed_refresh_lock, flags);
747 /* Reset the request flag */
748 par->delayed_refresh = false;
750 /* Store the dirty rectangle to local variables */
756 /* Clear dirty rectangle */
757 par->x1 = par->y1 = INT_MAX;
758 par->x2 = par->y2 = 0;
760 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
762 if (x1 > info->var.xres || x2 > info->var.xres ||
763 y1 > info->var.yres || y2 > info->var.yres || x2 <= x1)
766 /* Copy the dirty rectangle to frame buffer memory */
767 if (par->need_docopy)
768 for (j = y1; j < y2; j++)
770 j * info->fix.line_length +
771 (x1 * screen_depth / 8),
772 (x2 - x1) * screen_depth / 8);
775 if (par->fb_ready && par->update)
776 synthvid_update(info, x1, y1, x2, y2);
780 * Control the on-demand refresh frequency. It schedules a delayed
781 * screen update if it has not yet.
783 static void hvfb_ondemand_refresh_throttle(struct hvfb_par *par,
784 int x1, int y1, int w, int h)
790 spin_lock_irqsave(&par->delayed_refresh_lock, flags);
792 /* Merge dirty rectangle */
793 par->x1 = min_t(int, par->x1, x1);
794 par->y1 = min_t(int, par->y1, y1);
795 par->x2 = max_t(int, par->x2, x2);
796 par->y2 = max_t(int, par->y2, y2);
798 /* Schedule a delayed screen update if not yet */
799 if (par->delayed_refresh == false) {
800 schedule_delayed_work(&par->dwork,
801 HVFB_ONDEMAND_THROTTLE);
802 par->delayed_refresh = true;
805 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
808 static int hvfb_on_panic(struct notifier_block *nb,
809 unsigned long e, void *p)
811 struct hvfb_par *par;
812 struct fb_info *info;
814 par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
815 par->synchronous_fb = true;
817 if (par->need_docopy)
818 hvfb_docopy(par, 0, dio_fb_size);
819 synthvid_update(info, 0, 0, INT_MAX, INT_MAX);
824 /* Framebuffer operation handlers */
826 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
828 if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
829 var->xres > screen_width || var->yres > screen_height ||
830 var->bits_per_pixel != screen_depth)
833 var->xres_virtual = var->xres;
834 var->yres_virtual = var->yres;
839 static int hvfb_set_par(struct fb_info *info)
841 struct hv_device *hdev = device_to_hv_device(info->device);
843 return synthvid_send_situ(hdev);
847 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
849 return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
852 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
853 unsigned blue, unsigned transp, struct fb_info *info)
855 u32 *pal = info->pseudo_palette;
860 pal[regno] = chan_to_field(red, &info->var.red)
861 | chan_to_field(green, &info->var.green)
862 | chan_to_field(blue, &info->var.blue)
863 | chan_to_field(transp, &info->var.transp);
868 static int hvfb_blank(int blank, struct fb_info *info)
870 return 1; /* get fb_blank to set the colormap to all black */
873 static void hvfb_cfb_fillrect(struct fb_info *p,
874 const struct fb_fillrect *rect)
876 struct hvfb_par *par = p->par;
878 cfb_fillrect(p, rect);
879 if (par->synchronous_fb)
880 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
882 hvfb_ondemand_refresh_throttle(par, rect->dx, rect->dy,
883 rect->width, rect->height);
886 static void hvfb_cfb_copyarea(struct fb_info *p,
887 const struct fb_copyarea *area)
889 struct hvfb_par *par = p->par;
891 cfb_copyarea(p, area);
892 if (par->synchronous_fb)
893 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
895 hvfb_ondemand_refresh_throttle(par, area->dx, area->dy,
896 area->width, area->height);
899 static void hvfb_cfb_imageblit(struct fb_info *p,
900 const struct fb_image *image)
902 struct hvfb_par *par = p->par;
904 cfb_imageblit(p, image);
905 if (par->synchronous_fb)
906 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
908 hvfb_ondemand_refresh_throttle(par, image->dx, image->dy,
909 image->width, image->height);
912 static const struct fb_ops hvfb_ops = {
913 .owner = THIS_MODULE,
914 .fb_check_var = hvfb_check_var,
915 .fb_set_par = hvfb_set_par,
916 .fb_setcolreg = hvfb_setcolreg,
917 .fb_fillrect = hvfb_cfb_fillrect,
918 .fb_copyarea = hvfb_cfb_copyarea,
919 .fb_imageblit = hvfb_cfb_imageblit,
920 .fb_blank = hvfb_blank,
924 /* Get options from kernel paramenter "video=" */
925 static void hvfb_get_option(struct fb_info *info)
927 struct hvfb_par *par = info->par;
928 char *opt = NULL, *p;
931 if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
934 p = strsep(&opt, "x");
935 if (!*p || kstrtouint(p, 0, &x) ||
936 !opt || !*opt || kstrtouint(opt, 0, &y)) {
937 pr_err("Screen option is invalid: skipped\n");
941 if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
942 (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10) &&
943 (x > screen_width_max || y > screen_height_max)) ||
944 (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
945 x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8) ||
946 (par->synthvid_version == SYNTHVID_VERSION_WIN7 &&
947 (x > SYNTHVID_WIDTH_MAX_WIN7 || y > SYNTHVID_HEIGHT_MAX_WIN7))) {
948 pr_err("Screen resolution option is out of range: skipped\n");
958 * Allocate enough contiguous physical memory.
959 * Return physical address if succeeded or -1 if failed.
961 static phys_addr_t hvfb_get_phymem(struct hv_device *hdev,
962 unsigned int request_size)
964 struct page *page = NULL;
965 dma_addr_t dma_handle;
967 phys_addr_t paddr = 0;
968 unsigned int order = get_order(request_size);
970 if (request_size == 0)
973 if (order < MAX_ORDER) {
974 /* Call alloc_pages if the size is less than 2^MAX_ORDER */
975 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
979 paddr = (page_to_pfn(page) << PAGE_SHIFT);
981 /* Allocate from CMA */
982 hdev->device.coherent_dma_mask = DMA_BIT_MASK(64);
984 vmem = dma_alloc_coherent(&hdev->device,
985 round_up(request_size, PAGE_SIZE),
987 GFP_KERNEL | __GFP_NOWARN);
992 paddr = virt_to_phys(vmem);
998 /* Release contiguous physical memory */
999 static void hvfb_release_phymem(struct hv_device *hdev,
1000 phys_addr_t paddr, unsigned int size)
1002 unsigned int order = get_order(size);
1004 if (order < MAX_ORDER)
1005 __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order);
1007 dma_free_coherent(&hdev->device,
1008 round_up(size, PAGE_SIZE),
1009 phys_to_virt(paddr),
1014 /* Get framebuffer memory from Hyper-V video pci space */
1015 static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
1017 struct hvfb_par *par = info->par;
1018 struct pci_dev *pdev = NULL;
1019 void __iomem *fb_virt;
1020 int gen2vm = efi_enabled(EFI_BOOT);
1021 resource_size_t pot_start, pot_end;
1025 info->apertures = alloc_apertures(1);
1026 if (!info->apertures)
1030 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
1031 PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
1033 pr_err("Unable to find PCI Hyper-V video\n");
1037 info->apertures->ranges[0].base = pci_resource_start(pdev, 0);
1038 info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
1041 * For Gen 1 VM, we can directly use the contiguous memory
1042 * from VM. If we succeed, deferred IO happens directly
1043 * on this allocated framebuffer memory, avoiding extra
1046 paddr = hvfb_get_phymem(hdev, screen_fb_size);
1047 if (paddr != (phys_addr_t) -1) {
1048 par->mmio_pp = paddr;
1049 par->mmio_vp = par->dio_vp = __va(paddr);
1051 info->fix.smem_start = paddr;
1052 info->fix.smem_len = screen_fb_size;
1053 info->screen_base = par->mmio_vp;
1054 info->screen_size = screen_fb_size;
1056 par->need_docopy = false;
1059 pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n");
1061 info->apertures->ranges[0].base = screen_info.lfb_base;
1062 info->apertures->ranges[0].size = screen_info.lfb_size;
1066 * Cannot use the contiguous physical memory.
1067 * Allocate mmio space for framebuffer.
1070 screen_width * screen_height * screen_depth / 8;
1076 if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
1077 pci_resource_len(pdev, 0) < screen_fb_size) {
1078 pr_err("Resource not available or (0x%lx < 0x%lx)\n",
1079 (unsigned long) pci_resource_len(pdev, 0),
1080 (unsigned long) screen_fb_size);
1084 pot_end = pci_resource_end(pdev, 0);
1085 pot_start = pot_end - screen_fb_size + 1;
1088 ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
1089 screen_fb_size, 0x100000, true);
1091 pr_err("Unable to allocate framebuffer memory\n");
1096 * Map the VRAM cacheable for performance. This is also required for
1097 * VM Connect to display properly for ARM64 Linux VM, as the host also
1098 * maps the VRAM cacheable.
1100 fb_virt = ioremap_cache(par->mem->start, screen_fb_size);
1104 /* Allocate memory for deferred IO */
1105 par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE));
1106 if (par->dio_vp == NULL)
1109 /* Physical address of FB device */
1110 par->mmio_pp = par->mem->start;
1111 /* Virtual address of FB device */
1112 par->mmio_vp = (unsigned char *) fb_virt;
1114 info->fix.smem_start = par->mem->start;
1115 info->fix.smem_len = dio_fb_size;
1116 info->screen_base = par->dio_vp;
1117 info->screen_size = dio_fb_size;
1120 remove_conflicting_framebuffers(info->apertures,
1121 KBUILD_MODNAME, false);
1124 /* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */
1125 screen_info.lfb_size = 0;
1126 screen_info.lfb_base = 0;
1127 screen_info.orig_video_isVGA = 0;
1137 vmbus_free_mmio(par->mem->start, screen_fb_size);
1146 /* Release the framebuffer */
1147 static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info)
1149 struct hvfb_par *par = info->par;
1151 if (par->need_docopy) {
1153 iounmap(info->screen_base);
1154 vmbus_free_mmio(par->mem->start, screen_fb_size);
1156 hvfb_release_phymem(hdev, info->fix.smem_start,
1164 static int hvfb_probe(struct hv_device *hdev,
1165 const struct hv_vmbus_device_id *dev_id)
1167 struct fb_info *info;
1168 struct hvfb_par *par;
1171 info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
1177 par->fb_ready = false;
1178 par->need_docopy = true;
1179 init_completion(&par->wait);
1180 INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
1182 par->delayed_refresh = false;
1183 spin_lock_init(&par->delayed_refresh_lock);
1184 par->x1 = par->y1 = INT_MAX;
1185 par->x2 = par->y2 = 0;
1187 /* Connect to VSP */
1188 hv_set_drvdata(hdev, info);
1189 ret = synthvid_connect_vsp(hdev);
1191 pr_err("Unable to connect to VSP\n");
1195 hvfb_get_option(info);
1196 pr_info("Screen resolution: %dx%d, Color depth: %d\n",
1197 screen_width, screen_height, screen_depth);
1199 ret = hvfb_getmem(hdev, info);
1201 pr_err("No memory for framebuffer\n");
1205 /* Set up fb_info */
1206 info->flags = FBINFO_DEFAULT;
1208 info->var.xres_virtual = info->var.xres = screen_width;
1209 info->var.yres_virtual = info->var.yres = screen_height;
1210 info->var.bits_per_pixel = screen_depth;
1212 if (info->var.bits_per_pixel == 16) {
1213 info->var.red = (struct fb_bitfield){11, 5, 0};
1214 info->var.green = (struct fb_bitfield){5, 6, 0};
1215 info->var.blue = (struct fb_bitfield){0, 5, 0};
1216 info->var.transp = (struct fb_bitfield){0, 0, 0};
1218 info->var.red = (struct fb_bitfield){16, 8, 0};
1219 info->var.green = (struct fb_bitfield){8, 8, 0};
1220 info->var.blue = (struct fb_bitfield){0, 8, 0};
1221 info->var.transp = (struct fb_bitfield){24, 8, 0};
1224 info->var.activate = FB_ACTIVATE_NOW;
1225 info->var.height = -1;
1226 info->var.width = -1;
1227 info->var.vmode = FB_VMODE_NONINTERLACED;
1229 strcpy(info->fix.id, KBUILD_MODNAME);
1230 info->fix.type = FB_TYPE_PACKED_PIXELS;
1231 info->fix.visual = FB_VISUAL_TRUECOLOR;
1232 info->fix.line_length = screen_width * screen_depth / 8;
1233 info->fix.accel = FB_ACCEL_NONE;
1235 info->fbops = &hvfb_ops;
1236 info->pseudo_palette = par->pseudo_palette;
1238 /* Initialize deferred IO */
1239 info->fbdefio = &synthvid_defio;
1240 fb_deferred_io_init(info);
1242 /* Send config to host */
1243 ret = synthvid_send_config(hdev);
1247 ret = register_framebuffer(info);
1249 pr_err("Unable to register framebuffer\n");
1253 par->fb_ready = true;
1255 par->synchronous_fb = false;
1256 par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
1257 atomic_notifier_chain_register(&panic_notifier_list,
1258 &par->hvfb_panic_nb);
1263 fb_deferred_io_cleanup(info);
1264 hvfb_putmem(hdev, info);
1266 vmbus_close(hdev->channel);
1268 cancel_delayed_work_sync(&par->dwork);
1269 hv_set_drvdata(hdev, NULL);
1270 framebuffer_release(info);
1275 static int hvfb_remove(struct hv_device *hdev)
1277 struct fb_info *info = hv_get_drvdata(hdev);
1278 struct hvfb_par *par = info->par;
1280 atomic_notifier_chain_unregister(&panic_notifier_list,
1281 &par->hvfb_panic_nb);
1283 par->update = false;
1284 par->fb_ready = false;
1286 fb_deferred_io_cleanup(info);
1288 unregister_framebuffer(info);
1289 cancel_delayed_work_sync(&par->dwork);
1291 vmbus_close(hdev->channel);
1292 hv_set_drvdata(hdev, NULL);
1294 hvfb_putmem(hdev, info);
1295 framebuffer_release(info);
1300 static int hvfb_suspend(struct hv_device *hdev)
1302 struct fb_info *info = hv_get_drvdata(hdev);
1303 struct hvfb_par *par = info->par;
1307 /* 1 means do suspend */
1308 fb_set_suspend(info, 1);
1310 cancel_delayed_work_sync(&par->dwork);
1311 cancel_delayed_work_sync(&info->deferred_work);
1313 par->update_saved = par->update;
1314 par->update = false;
1315 par->fb_ready = false;
1317 vmbus_close(hdev->channel);
1324 static int hvfb_resume(struct hv_device *hdev)
1326 struct fb_info *info = hv_get_drvdata(hdev);
1327 struct hvfb_par *par = info->par;
1332 ret = synthvid_connect_vsp(hdev);
1336 ret = synthvid_send_config(hdev);
1338 vmbus_close(hdev->channel);
1342 par->fb_ready = true;
1343 par->update = par->update_saved;
1345 schedule_delayed_work(&info->deferred_work, info->fbdefio->delay);
1346 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
1348 /* 0 means do resume */
1349 fb_set_suspend(info, 0);
1358 static const struct pci_device_id pci_stub_id_table[] = {
1360 .vendor = PCI_VENDOR_ID_MICROSOFT,
1361 .device = PCI_DEVICE_ID_HYPERV_VIDEO,
1363 { /* end of list */ }
1366 static const struct hv_vmbus_device_id id_table[] = {
1367 /* Synthetic Video Device GUID */
1372 MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
1373 MODULE_DEVICE_TABLE(vmbus, id_table);
1375 static struct hv_driver hvfb_drv = {
1376 .name = KBUILD_MODNAME,
1377 .id_table = id_table,
1378 .probe = hvfb_probe,
1379 .remove = hvfb_remove,
1380 .suspend = hvfb_suspend,
1381 .resume = hvfb_resume,
1383 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1387 static int hvfb_pci_stub_probe(struct pci_dev *pdev,
1388 const struct pci_device_id *ent)
1393 static void hvfb_pci_stub_remove(struct pci_dev *pdev)
1397 static struct pci_driver hvfb_pci_stub_driver = {
1398 .name = KBUILD_MODNAME,
1399 .id_table = pci_stub_id_table,
1400 .probe = hvfb_pci_stub_probe,
1401 .remove = hvfb_pci_stub_remove,
1403 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1407 static int __init hvfb_drv_init(void)
1411 ret = vmbus_driver_register(&hvfb_drv);
1415 ret = pci_register_driver(&hvfb_pci_stub_driver);
1417 vmbus_driver_unregister(&hvfb_drv);
1424 static void __exit hvfb_drv_exit(void)
1426 pci_unregister_driver(&hvfb_pci_stub_driver);
1427 vmbus_driver_unregister(&hvfb_drv);
1430 module_init(hvfb_drv_init);
1431 module_exit(hvfb_drv_exit);
1433 MODULE_LICENSE("GPL");
1434 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");