1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2012, Microsoft Corporation.
6 * Haiyang Zhang <haiyangz@microsoft.com>
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_depth;
290 static uint screen_fb_size;
291 static uint dio_fb_size; /* FB size for deferred IO */
293 /* Send message to Hyper-V host */
294 static inline int synthvid_send(struct hv_device *hdev,
295 struct synthvid_msg *msg)
297 static atomic64_t request_id = ATOMIC64_INIT(0);
300 msg->pipe_hdr.type = PIPE_MSG_DATA;
301 msg->pipe_hdr.size = msg->vid_hdr.size;
303 ret = vmbus_sendpacket(hdev->channel, msg,
304 msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
305 atomic64_inc_return(&request_id),
306 VM_PKT_DATA_INBAND, 0);
309 pr_err("Unable to send packet via vmbus\n");
315 /* Send screen resolution info to host */
316 static int synthvid_send_situ(struct hv_device *hdev)
318 struct fb_info *info = hv_get_drvdata(hdev);
319 struct synthvid_msg msg;
324 memset(&msg, 0, sizeof(struct synthvid_msg));
326 msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
327 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
328 sizeof(struct synthvid_situation_update);
329 msg.situ.user_ctx = 0;
330 msg.situ.video_output_count = 1;
331 msg.situ.video_output[0].active = 1;
332 msg.situ.video_output[0].vram_offset = 0;
333 msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
334 msg.situ.video_output[0].width_pixels = info->var.xres;
335 msg.situ.video_output[0].height_pixels = info->var.yres;
336 msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
338 synthvid_send(hdev, &msg);
343 /* Send mouse pointer info to host */
344 static int synthvid_send_ptr(struct hv_device *hdev)
346 struct synthvid_msg msg;
348 memset(&msg, 0, sizeof(struct synthvid_msg));
349 msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
350 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
351 sizeof(struct synthvid_pointer_position);
352 msg.ptr_pos.is_visible = 1;
353 msg.ptr_pos.video_output = 0;
354 msg.ptr_pos.image_x = 0;
355 msg.ptr_pos.image_y = 0;
356 synthvid_send(hdev, &msg);
358 memset(&msg, 0, sizeof(struct synthvid_msg));
359 msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
360 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
361 sizeof(struct synthvid_pointer_shape);
362 msg.ptr_shape.part_idx = CURSOR_COMPLETE;
363 msg.ptr_shape.is_argb = 1;
364 msg.ptr_shape.width = 1;
365 msg.ptr_shape.height = 1;
366 msg.ptr_shape.hot_x = 0;
367 msg.ptr_shape.hot_y = 0;
368 msg.ptr_shape.data[0] = 0;
369 msg.ptr_shape.data[1] = 1;
370 msg.ptr_shape.data[2] = 1;
371 msg.ptr_shape.data[3] = 1;
372 synthvid_send(hdev, &msg);
377 /* Send updated screen area (dirty rectangle) location to host */
379 synthvid_update(struct fb_info *info, int x1, int y1, int x2, int y2)
381 struct hv_device *hdev = device_to_hv_device(info->device);
382 struct synthvid_msg msg;
384 memset(&msg, 0, sizeof(struct synthvid_msg));
390 msg.vid_hdr.type = SYNTHVID_DIRT;
391 msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
392 sizeof(struct synthvid_dirt);
393 msg.dirt.video_output = 0;
394 msg.dirt.dirt_count = 1;
395 msg.dirt.rect[0].x1 = (x1 > x2) ? 0 : x1;
396 msg.dirt.rect[0].y1 = (y1 > y2) ? 0 : y1;
397 msg.dirt.rect[0].x2 =
398 (x2 < x1 || x2 > info->var.xres) ? info->var.xres : x2;
399 msg.dirt.rect[0].y2 =
400 (y2 < y1 || y2 > info->var.yres) ? info->var.yres : y2;
402 synthvid_send(hdev, &msg);
407 static void hvfb_docopy(struct hvfb_par *par,
408 unsigned long offset,
411 if (!par || !par->mmio_vp || !par->dio_vp || !par->fb_ready ||
412 size == 0 || offset >= dio_fb_size)
415 if (offset + size > dio_fb_size)
416 size = dio_fb_size - offset;
418 memcpy(par->mmio_vp + offset, par->dio_vp + offset, size);
421 /* Deferred IO callback */
422 static void synthvid_deferred_io(struct fb_info *p,
423 struct list_head *pagelist)
425 struct hvfb_par *par = p->par;
427 unsigned long start, end;
428 int y1, y2, miny, maxy;
434 * Merge dirty pages. It is possible that last page cross
435 * over the end of frame buffer row yres. This is taken care of
436 * in synthvid_update function by clamping the y2
439 list_for_each_entry(page, pagelist, lru) {
440 start = page->index << PAGE_SHIFT;
441 end = start + PAGE_SIZE - 1;
442 y1 = start / p->fix.line_length;
443 y2 = end / p->fix.line_length;
444 miny = min_t(int, miny, y1);
445 maxy = max_t(int, maxy, y2);
447 /* Copy from dio space to mmio address */
448 if (par->fb_ready && par->need_docopy)
449 hvfb_docopy(par, start, PAGE_SIZE);
452 if (par->fb_ready && par->update)
453 synthvid_update(p, 0, miny, p->var.xres, maxy + 1);
456 static struct fb_deferred_io synthvid_defio = {
458 .deferred_io = synthvid_deferred_io,
462 * Actions on received messages from host:
463 * Complete the wait event.
464 * Or, reply with screen and cursor info.
466 static void synthvid_recv_sub(struct hv_device *hdev)
468 struct fb_info *info = hv_get_drvdata(hdev);
469 struct hvfb_par *par;
470 struct synthvid_msg *msg;
476 msg = (struct synthvid_msg *)par->recv_buf;
478 /* Complete the wait event */
479 if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
480 msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE ||
481 msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
482 memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
483 complete(&par->wait);
487 /* Reply with screen and cursor info */
488 if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
490 synthvid_send_ptr(hdev);
491 synthvid_send_situ(hdev);
494 par->update = msg->feature_chg.is_dirt_needed;
496 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
500 /* Receive callback for messages from the host */
501 static void synthvid_receive(void *ctx)
503 struct hv_device *hdev = ctx;
504 struct fb_info *info = hv_get_drvdata(hdev);
505 struct hvfb_par *par;
506 struct synthvid_msg *recv_buf;
515 recv_buf = (struct synthvid_msg *)par->recv_buf;
518 ret = vmbus_recvpacket(hdev->channel, recv_buf,
520 &bytes_recvd, &req_id);
521 if (bytes_recvd > 0 &&
522 recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
523 synthvid_recv_sub(hdev);
524 } while (bytes_recvd > 0 && ret == 0);
527 /* Check if the ver1 version is equal or greater than ver2 */
528 static inline bool synthvid_ver_ge(u32 ver1, u32 ver2)
530 if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) ||
531 (SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) &&
532 SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2)))
538 /* Check synthetic video protocol version with the host */
539 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
541 struct fb_info *info = hv_get_drvdata(hdev);
542 struct hvfb_par *par = info->par;
543 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
547 memset(msg, 0, sizeof(struct synthvid_msg));
548 msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
549 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
550 sizeof(struct synthvid_version_req);
551 msg->ver_req.version = ver;
552 synthvid_send(hdev, msg);
554 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
556 pr_err("Time out on waiting version response\n");
560 if (!msg->ver_resp.is_accepted) {
565 par->synthvid_version = ver;
566 pr_info("Synthvid Version major %d, minor %d\n",
567 SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver));
573 /* Get current resolution from the host */
574 static int synthvid_get_supported_resolution(struct hv_device *hdev)
576 struct fb_info *info = hv_get_drvdata(hdev);
577 struct hvfb_par *par = info->par;
578 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
583 memset(msg, 0, sizeof(struct synthvid_msg));
584 msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST;
585 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
586 sizeof(struct synthvid_supported_resolution_req);
588 msg->resolution_req.maximum_resolution_count =
589 SYNTHVID_MAX_RESOLUTION_COUNT;
590 synthvid_send(hdev, msg);
592 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
594 pr_err("Time out on waiting resolution response\n");
599 if (msg->resolution_resp.resolution_count == 0) {
600 pr_err("No supported resolutions\n");
605 index = msg->resolution_resp.default_resolution_index;
606 if (index >= msg->resolution_resp.resolution_count) {
607 pr_err("Invalid resolution index: %d\n", index);
613 msg->resolution_resp.supported_resolution[index].width;
615 msg->resolution_resp.supported_resolution[index].height;
621 /* Connect to VSP (Virtual Service Provider) on host */
622 static int synthvid_connect_vsp(struct hv_device *hdev)
624 struct fb_info *info = hv_get_drvdata(hdev);
625 struct hvfb_par *par = info->par;
628 ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
629 NULL, 0, synthvid_receive, hdev);
631 pr_err("Unable to open vmbus channel\n");
635 /* Negotiate the protocol version with host */
636 switch (vmbus_proto_version) {
638 case VERSION_WIN10_V5:
639 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
645 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
651 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN7);
654 ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
659 pr_err("Synthetic video device version not accepted\n");
663 if (par->synthvid_version == SYNTHVID_VERSION_WIN7)
664 screen_depth = SYNTHVID_DEPTH_WIN7;
666 screen_depth = SYNTHVID_DEPTH_WIN8;
668 if (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10)) {
669 ret = synthvid_get_supported_resolution(hdev);
671 pr_info("Failed to get supported resolution from host, use default\n");
674 screen_fb_size = hdev->channel->offermsg.offer.
675 mmio_megabytes * 1024 * 1024;
680 vmbus_close(hdev->channel);
684 /* Send VRAM and Situation messages to the host */
685 static int synthvid_send_config(struct hv_device *hdev)
687 struct fb_info *info = hv_get_drvdata(hdev);
688 struct hvfb_par *par = info->par;
689 struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
693 /* Send VRAM location */
694 memset(msg, 0, sizeof(struct synthvid_msg));
695 msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
696 msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
697 sizeof(struct synthvid_vram_location);
698 msg->vram.user_ctx = msg->vram.vram_gpa = par->mmio_pp;
699 msg->vram.is_vram_gpa_specified = 1;
700 synthvid_send(hdev, msg);
702 t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
704 pr_err("Time out on waiting vram location ack\n");
708 if (msg->vram_ack.user_ctx != par->mmio_pp) {
709 pr_err("Unable to set VRAM location\n");
714 /* Send pointer and situation update */
715 synthvid_send_ptr(hdev);
716 synthvid_send_situ(hdev);
724 * Delayed work callback:
725 * It is scheduled to call whenever update request is received and it has
726 * not been called in last HVFB_ONDEMAND_THROTTLE time interval.
728 static void hvfb_update_work(struct work_struct *w)
730 struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
731 struct fb_info *info = par->info;
736 spin_lock_irqsave(&par->delayed_refresh_lock, flags);
737 /* Reset the request flag */
738 par->delayed_refresh = false;
740 /* Store the dirty rectangle to local variables */
746 /* Clear dirty rectangle */
747 par->x1 = par->y1 = INT_MAX;
748 par->x2 = par->y2 = 0;
750 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
752 if (x1 > info->var.xres || x2 > info->var.xres ||
753 y1 > info->var.yres || y2 > info->var.yres || x2 <= x1)
756 /* Copy the dirty rectangle to frame buffer memory */
757 if (par->need_docopy)
758 for (j = y1; j < y2; j++)
760 j * info->fix.line_length +
761 (x1 * screen_depth / 8),
762 (x2 - x1) * screen_depth / 8);
765 if (par->fb_ready && par->update)
766 synthvid_update(info, x1, y1, x2, y2);
770 * Control the on-demand refresh frequency. It schedules a delayed
771 * screen update if it has not yet.
773 static void hvfb_ondemand_refresh_throttle(struct hvfb_par *par,
774 int x1, int y1, int w, int h)
780 spin_lock_irqsave(&par->delayed_refresh_lock, flags);
782 /* Merge dirty rectangle */
783 par->x1 = min_t(int, par->x1, x1);
784 par->y1 = min_t(int, par->y1, y1);
785 par->x2 = max_t(int, par->x2, x2);
786 par->y2 = max_t(int, par->y2, y2);
788 /* Schedule a delayed screen update if not yet */
789 if (par->delayed_refresh == false) {
790 schedule_delayed_work(&par->dwork,
791 HVFB_ONDEMAND_THROTTLE);
792 par->delayed_refresh = true;
795 spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
798 static int hvfb_on_panic(struct notifier_block *nb,
799 unsigned long e, void *p)
801 struct hvfb_par *par;
802 struct fb_info *info;
804 par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
805 par->synchronous_fb = true;
807 if (par->need_docopy)
808 hvfb_docopy(par, 0, dio_fb_size);
809 synthvid_update(info, 0, 0, INT_MAX, INT_MAX);
814 /* Framebuffer operation handlers */
816 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
818 if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
819 var->xres > screen_width || var->yres > screen_height ||
820 var->bits_per_pixel != screen_depth)
823 var->xres_virtual = var->xres;
824 var->yres_virtual = var->yres;
829 static int hvfb_set_par(struct fb_info *info)
831 struct hv_device *hdev = device_to_hv_device(info->device);
833 return synthvid_send_situ(hdev);
837 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
839 return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
842 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
843 unsigned blue, unsigned transp, struct fb_info *info)
845 u32 *pal = info->pseudo_palette;
850 pal[regno] = chan_to_field(red, &info->var.red)
851 | chan_to_field(green, &info->var.green)
852 | chan_to_field(blue, &info->var.blue)
853 | chan_to_field(transp, &info->var.transp);
858 static int hvfb_blank(int blank, struct fb_info *info)
860 return 1; /* get fb_blank to set the colormap to all black */
863 static void hvfb_cfb_fillrect(struct fb_info *p,
864 const struct fb_fillrect *rect)
866 struct hvfb_par *par = p->par;
868 cfb_fillrect(p, rect);
869 if (par->synchronous_fb)
870 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
872 hvfb_ondemand_refresh_throttle(par, rect->dx, rect->dy,
873 rect->width, rect->height);
876 static void hvfb_cfb_copyarea(struct fb_info *p,
877 const struct fb_copyarea *area)
879 struct hvfb_par *par = p->par;
881 cfb_copyarea(p, area);
882 if (par->synchronous_fb)
883 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
885 hvfb_ondemand_refresh_throttle(par, area->dx, area->dy,
886 area->width, area->height);
889 static void hvfb_cfb_imageblit(struct fb_info *p,
890 const struct fb_image *image)
892 struct hvfb_par *par = p->par;
894 cfb_imageblit(p, image);
895 if (par->synchronous_fb)
896 synthvid_update(p, 0, 0, INT_MAX, INT_MAX);
898 hvfb_ondemand_refresh_throttle(par, image->dx, image->dy,
899 image->width, image->height);
902 static const struct fb_ops hvfb_ops = {
903 .owner = THIS_MODULE,
904 .fb_check_var = hvfb_check_var,
905 .fb_set_par = hvfb_set_par,
906 .fb_setcolreg = hvfb_setcolreg,
907 .fb_fillrect = hvfb_cfb_fillrect,
908 .fb_copyarea = hvfb_cfb_copyarea,
909 .fb_imageblit = hvfb_cfb_imageblit,
910 .fb_blank = hvfb_blank,
914 /* Get options from kernel paramenter "video=" */
915 static void hvfb_get_option(struct fb_info *info)
917 struct hvfb_par *par = info->par;
918 char *opt = NULL, *p;
921 if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
924 p = strsep(&opt, "x");
925 if (!*p || kstrtouint(p, 0, &x) ||
926 !opt || !*opt || kstrtouint(opt, 0, &y)) {
927 pr_err("Screen option is invalid: skipped\n");
931 if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
932 (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10) &&
933 (x * y * screen_depth / 8 > screen_fb_size)) ||
934 (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
935 x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8) ||
936 (par->synthvid_version == SYNTHVID_VERSION_WIN7 &&
937 (x > SYNTHVID_WIDTH_MAX_WIN7 || y > SYNTHVID_HEIGHT_MAX_WIN7))) {
938 pr_err("Screen resolution option is out of range: skipped\n");
948 * Allocate enough contiguous physical memory.
949 * Return physical address if succeeded or -1 if failed.
951 static phys_addr_t hvfb_get_phymem(struct hv_device *hdev,
952 unsigned int request_size)
954 struct page *page = NULL;
955 dma_addr_t dma_handle;
957 phys_addr_t paddr = 0;
958 unsigned int order = get_order(request_size);
960 if (request_size == 0)
963 if (order < MAX_ORDER) {
964 /* Call alloc_pages if the size is less than 2^MAX_ORDER */
965 page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
969 paddr = (page_to_pfn(page) << PAGE_SHIFT);
971 /* Allocate from CMA */
972 hdev->device.coherent_dma_mask = DMA_BIT_MASK(64);
974 vmem = dma_alloc_coherent(&hdev->device,
975 round_up(request_size, PAGE_SIZE),
977 GFP_KERNEL | __GFP_NOWARN);
982 paddr = virt_to_phys(vmem);
988 /* Release contiguous physical memory */
989 static void hvfb_release_phymem(struct hv_device *hdev,
990 phys_addr_t paddr, unsigned int size)
992 unsigned int order = get_order(size);
994 if (order < MAX_ORDER)
995 __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order);
997 dma_free_coherent(&hdev->device,
998 round_up(size, PAGE_SIZE),
1004 /* Get framebuffer memory from Hyper-V video pci space */
1005 static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
1007 struct hvfb_par *par = info->par;
1008 struct pci_dev *pdev = NULL;
1009 void __iomem *fb_virt;
1010 int gen2vm = efi_enabled(EFI_BOOT);
1014 info->apertures = alloc_apertures(1);
1015 if (!info->apertures)
1019 pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
1020 PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
1022 pr_err("Unable to find PCI Hyper-V video\n");
1026 info->apertures->ranges[0].base = pci_resource_start(pdev, 0);
1027 info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
1030 * For Gen 1 VM, we can directly use the contiguous memory
1031 * from VM. If we succeed, deferred IO happens directly
1032 * on this allocated framebuffer memory, avoiding extra
1035 paddr = hvfb_get_phymem(hdev, screen_fb_size);
1036 if (paddr != (phys_addr_t) -1) {
1037 par->mmio_pp = paddr;
1038 par->mmio_vp = par->dio_vp = __va(paddr);
1040 info->fix.smem_start = paddr;
1041 info->fix.smem_len = screen_fb_size;
1042 info->screen_base = par->mmio_vp;
1043 info->screen_size = screen_fb_size;
1045 par->need_docopy = false;
1048 pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n");
1050 info->apertures->ranges[0].base = screen_info.lfb_base;
1051 info->apertures->ranges[0].size = screen_info.lfb_size;
1055 * Cannot use the contiguous physical memory.
1056 * Allocate mmio space for framebuffer.
1059 screen_width * screen_height * screen_depth / 8;
1061 ret = vmbus_allocate_mmio(&par->mem, hdev, 0, -1,
1062 screen_fb_size, 0x100000, true);
1064 pr_err("Unable to allocate framebuffer memory\n");
1069 * Map the VRAM cacheable for performance. This is also required for
1070 * VM Connect to display properly for ARM64 Linux VM, as the host also
1071 * maps the VRAM cacheable.
1073 fb_virt = ioremap_cache(par->mem->start, screen_fb_size);
1077 /* Allocate memory for deferred IO */
1078 par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE));
1079 if (par->dio_vp == NULL)
1082 /* Physical address of FB device */
1083 par->mmio_pp = par->mem->start;
1084 /* Virtual address of FB device */
1085 par->mmio_vp = (unsigned char *) fb_virt;
1087 info->fix.smem_start = par->mem->start;
1088 info->fix.smem_len = dio_fb_size;
1089 info->screen_base = par->dio_vp;
1090 info->screen_size = dio_fb_size;
1093 remove_conflicting_framebuffers(info->apertures,
1094 KBUILD_MODNAME, false);
1097 /* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */
1098 screen_info.lfb_size = 0;
1099 screen_info.lfb_base = 0;
1100 screen_info.orig_video_isVGA = 0;
1110 vmbus_free_mmio(par->mem->start, screen_fb_size);
1119 /* Release the framebuffer */
1120 static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info)
1122 struct hvfb_par *par = info->par;
1124 if (par->need_docopy) {
1126 iounmap(info->screen_base);
1127 vmbus_free_mmio(par->mem->start, screen_fb_size);
1129 hvfb_release_phymem(hdev, info->fix.smem_start,
1137 static int hvfb_probe(struct hv_device *hdev,
1138 const struct hv_vmbus_device_id *dev_id)
1140 struct fb_info *info;
1141 struct hvfb_par *par;
1144 info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
1150 par->fb_ready = false;
1151 par->need_docopy = true;
1152 init_completion(&par->wait);
1153 INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
1155 par->delayed_refresh = false;
1156 spin_lock_init(&par->delayed_refresh_lock);
1157 par->x1 = par->y1 = INT_MAX;
1158 par->x2 = par->y2 = 0;
1160 /* Connect to VSP */
1161 hv_set_drvdata(hdev, info);
1162 ret = synthvid_connect_vsp(hdev);
1164 pr_err("Unable to connect to VSP\n");
1168 hvfb_get_option(info);
1169 pr_info("Screen resolution: %dx%d, Color depth: %d, Frame buffer size: %d\n",
1170 screen_width, screen_height, screen_depth, screen_fb_size);
1172 ret = hvfb_getmem(hdev, info);
1174 pr_err("No memory for framebuffer\n");
1178 /* Set up fb_info */
1179 info->flags = FBINFO_DEFAULT;
1181 info->var.xres_virtual = info->var.xres = screen_width;
1182 info->var.yres_virtual = info->var.yres = screen_height;
1183 info->var.bits_per_pixel = screen_depth;
1185 if (info->var.bits_per_pixel == 16) {
1186 info->var.red = (struct fb_bitfield){11, 5, 0};
1187 info->var.green = (struct fb_bitfield){5, 6, 0};
1188 info->var.blue = (struct fb_bitfield){0, 5, 0};
1189 info->var.transp = (struct fb_bitfield){0, 0, 0};
1191 info->var.red = (struct fb_bitfield){16, 8, 0};
1192 info->var.green = (struct fb_bitfield){8, 8, 0};
1193 info->var.blue = (struct fb_bitfield){0, 8, 0};
1194 info->var.transp = (struct fb_bitfield){24, 8, 0};
1197 info->var.activate = FB_ACTIVATE_NOW;
1198 info->var.height = -1;
1199 info->var.width = -1;
1200 info->var.vmode = FB_VMODE_NONINTERLACED;
1202 strcpy(info->fix.id, KBUILD_MODNAME);
1203 info->fix.type = FB_TYPE_PACKED_PIXELS;
1204 info->fix.visual = FB_VISUAL_TRUECOLOR;
1205 info->fix.line_length = screen_width * screen_depth / 8;
1206 info->fix.accel = FB_ACCEL_NONE;
1208 info->fbops = &hvfb_ops;
1209 info->pseudo_palette = par->pseudo_palette;
1211 /* Initialize deferred IO */
1212 info->fbdefio = &synthvid_defio;
1213 fb_deferred_io_init(info);
1215 /* Send config to host */
1216 ret = synthvid_send_config(hdev);
1220 ret = register_framebuffer(info);
1222 pr_err("Unable to register framebuffer\n");
1226 par->fb_ready = true;
1228 par->synchronous_fb = false;
1229 par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
1230 atomic_notifier_chain_register(&panic_notifier_list,
1231 &par->hvfb_panic_nb);
1236 fb_deferred_io_cleanup(info);
1237 hvfb_putmem(hdev, info);
1239 vmbus_close(hdev->channel);
1241 cancel_delayed_work_sync(&par->dwork);
1242 hv_set_drvdata(hdev, NULL);
1243 framebuffer_release(info);
1248 static int hvfb_remove(struct hv_device *hdev)
1250 struct fb_info *info = hv_get_drvdata(hdev);
1251 struct hvfb_par *par = info->par;
1253 atomic_notifier_chain_unregister(&panic_notifier_list,
1254 &par->hvfb_panic_nb);
1256 par->update = false;
1257 par->fb_ready = false;
1259 fb_deferred_io_cleanup(info);
1261 unregister_framebuffer(info);
1262 cancel_delayed_work_sync(&par->dwork);
1264 vmbus_close(hdev->channel);
1265 hv_set_drvdata(hdev, NULL);
1267 hvfb_putmem(hdev, info);
1268 framebuffer_release(info);
1273 static int hvfb_suspend(struct hv_device *hdev)
1275 struct fb_info *info = hv_get_drvdata(hdev);
1276 struct hvfb_par *par = info->par;
1280 /* 1 means do suspend */
1281 fb_set_suspend(info, 1);
1283 cancel_delayed_work_sync(&par->dwork);
1284 cancel_delayed_work_sync(&info->deferred_work);
1286 par->update_saved = par->update;
1287 par->update = false;
1288 par->fb_ready = false;
1290 vmbus_close(hdev->channel);
1297 static int hvfb_resume(struct hv_device *hdev)
1299 struct fb_info *info = hv_get_drvdata(hdev);
1300 struct hvfb_par *par = info->par;
1305 ret = synthvid_connect_vsp(hdev);
1309 ret = synthvid_send_config(hdev);
1311 vmbus_close(hdev->channel);
1315 par->fb_ready = true;
1316 par->update = par->update_saved;
1318 schedule_delayed_work(&info->deferred_work, info->fbdefio->delay);
1319 schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
1321 /* 0 means do resume */
1322 fb_set_suspend(info, 0);
1331 static const struct pci_device_id pci_stub_id_table[] = {
1333 .vendor = PCI_VENDOR_ID_MICROSOFT,
1334 .device = PCI_DEVICE_ID_HYPERV_VIDEO,
1336 { /* end of list */ }
1339 static const struct hv_vmbus_device_id id_table[] = {
1340 /* Synthetic Video Device GUID */
1345 MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
1346 MODULE_DEVICE_TABLE(vmbus, id_table);
1348 static struct hv_driver hvfb_drv = {
1349 .name = KBUILD_MODNAME,
1350 .id_table = id_table,
1351 .probe = hvfb_probe,
1352 .remove = hvfb_remove,
1353 .suspend = hvfb_suspend,
1354 .resume = hvfb_resume,
1356 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1360 static int hvfb_pci_stub_probe(struct pci_dev *pdev,
1361 const struct pci_device_id *ent)
1366 static void hvfb_pci_stub_remove(struct pci_dev *pdev)
1370 static struct pci_driver hvfb_pci_stub_driver = {
1371 .name = KBUILD_MODNAME,
1372 .id_table = pci_stub_id_table,
1373 .probe = hvfb_pci_stub_probe,
1374 .remove = hvfb_pci_stub_remove,
1376 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1380 static int __init hvfb_drv_init(void)
1384 ret = vmbus_driver_register(&hvfb_drv);
1388 ret = pci_register_driver(&hvfb_pci_stub_driver);
1390 vmbus_driver_unregister(&hvfb_drv);
1397 static void __exit hvfb_drv_exit(void)
1399 pci_unregister_driver(&hvfb_pci_stub_driver);
1400 vmbus_driver_unregister(&hvfb_drv);
1403 module_init(hvfb_drv_init);
1404 module_exit(hvfb_drv_exit);
1406 MODULE_LICENSE("GPL");
1407 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");