xref: /linux/drivers/video/fbdev/hyperv_fb.c (revision 0fed89a961ea851945d23cc35beb59d6e56c0964)
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 
77 enum pipe_msg_type {
78 	PIPE_MSG_INVALID,
79 	PIPE_MSG_DATA,
80 	PIPE_MSG_MAX
81 };
82 
83 struct pipe_msg_hdr {
84 	u32 type;
85 	u32 size; /* size of message after this field */
86 } __packed;
87 
88 
89 enum 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 
110 struct hvd_screen_info {
111 	u16 width;
112 	u16 height;
113 } __packed;
114 
115 struct synthvid_msg_hdr {
116 	u32 type;
117 	u32 size;  /* size of this header + payload after this field*/
118 } __packed;
119 
120 struct synthvid_version_req {
121 	u32 version;
122 } __packed;
123 
124 struct synthvid_version_resp {
125 	u32 version;
126 	u8 is_accepted;
127 	u8 max_video_outputs;
128 } __packed;
129 
130 struct synthvid_supported_resolution_req {
131 	u8 maximum_resolution_count;
132 } __packed;
133 
134 struct 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 
143 struct synthvid_vram_location {
144 	u64 user_ctx;
145 	u8 is_vram_gpa_specified;
146 	u64 vram_gpa;
147 } __packed;
148 
149 struct synthvid_vram_location_ack {
150 	u64 user_ctx;
151 } __packed;
152 
153 struct 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 
162 struct synthvid_situation_update {
163 	u64 user_ctx;
164 	u8 video_output_count;
165 	struct video_output_situation video_output[1];
166 } __packed;
167 
168 struct synthvid_situation_update_ack {
169 	u64 user_ctx;
170 } __packed;
171 
172 struct 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 
186 struct 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 
196 struct 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 
203 struct rect {
204 	s32 x1, y1; /* top left corner */
205 	s32 x2, y2; /* bottom right corner, exclusive */
206 } __packed;
207 
208 struct synthvid_dirt {
209 	u8 video_output;
210 	u8 dirt_count;
211 	struct rect rect[1];
212 } __packed;
213 
214 struct 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 
245 struct 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 
279 static uint screen_width = HVFB_WIDTH;
280 static uint screen_height = HVFB_HEIGHT;
281 static uint screen_depth;
282 static uint screen_fb_size;
283 static uint dio_fb_size; /* FB size for deferred IO */
284 
285 static void hvfb_putmem(struct fb_info *info);
286 
287 /* Send message to Hyper-V host */
synthvid_send(struct hv_device * hdev,struct synthvid_msg * msg)288 static 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(hdev->channel, msg,
298 			       msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
299 			       atomic64_inc_return(&request_id),
300 			       VM_PKT_DATA_INBAND, 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 */
synthvid_send_situ(struct hv_device * hdev)310 static int synthvid_send_situ(struct hv_device *hdev)
311 {
312 	struct fb_info *info = hv_get_drvdata(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);
333 
334 	return 0;
335 }
336 
337 /* Send mouse pointer info to host */
synthvid_send_ptr(struct hv_device * hdev)338 static 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);
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);
367 
368 	return 0;
369 }
370 
371 /* Send updated screen area (dirty rectangle) location to host */
372 static int
synthvid_update(struct fb_info * info,int x1,int y1,int x2,int y2)373 synthvid_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);
397 
398 	return 0;
399 }
400 
hvfb_docopy(struct hvfb_par * par,unsigned long offset,unsigned long size)401 static 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 */
synthvid_deferred_io(struct fb_info * p,struct list_head * pagereflist)416 static 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, start, PAGE_SIZE);
443 	}
444 
445 	if (par->fb_ready && par->update)
446 		synthvid_update(p, 0, miny, p->var.xres, maxy + 1);
447 }
448 
449 static 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  */
synthvid_recv_sub(struct hv_device * hdev)459 static void synthvid_recv_sub(struct hv_device *hdev)
460 {
461 	struct fb_info *info = hv_get_drvdata(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(&par->dwork, HVFB_UPDATE_DELAY);
490 	}
491 }
492 
493 /* Receive callback for messages from the host */
synthvid_receive(void * ctx)494 static void synthvid_receive(void *ctx)
495 {
496 	struct hv_device *hdev = ctx;
497 	struct fb_info *info = hv_get_drvdata(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(hdev->channel, recv_buf,
512 				       MAX_VMBUS_PKT_SIZE,
513 				       &bytes_recvd, &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 */
synthvid_ver_ge(u32 ver1,u32 ver2)521 static 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 */
synthvid_negotiate_ver(struct hv_device * hdev,u32 ver)532 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
533 {
534 	struct fb_info *info = hv_get_drvdata(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(&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 
562 out:
563 	return ret;
564 }
565 
566 /* Get current resolution from the host */
synthvid_get_supported_resolution(struct hv_device * hdev)567 static int synthvid_get_supported_resolution(struct hv_device *hdev)
568 {
569 	struct fb_info *info = hv_get_drvdata(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(&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 
610 out:
611 	return ret;
612 }
613 
614 /* Connect to VSP (Virtual Service Provider) on host */
synthvid_connect_vsp(struct hv_device * hdev)615 static int synthvid_connect_vsp(struct hv_device *hdev)
616 {
617 	struct fb_info *info = hv_get_drvdata(hdev);
618 	struct hvfb_par *par = info->par;
619 	int ret;
620 
621 	ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
622 			 NULL, 0, synthvid_receive, 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(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 
662 error:
663 	vmbus_close(hdev->channel);
664 	return ret;
665 }
666 
667 /* Send VRAM and Situation messages to the host */
synthvid_send_config(struct hv_device * hdev)668 static int synthvid_send_config(struct hv_device *hdev)
669 {
670 	struct fb_info *info = hv_get_drvdata(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(&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 
701 out:
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  */
hvfb_update_work(struct work_struct * w)711 static 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(&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 				    j * info->fix.line_length +
744 				    (x1 * screen_depth / 8),
745 				    (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  */
hvfb_ondemand_refresh_throttle(struct hvfb_par * par,int x1,int y1,int w,int h)756 static 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(&par->dwork,
774 				      HVFB_ONDEMAND_THROTTLE);
775 		par->delayed_refresh = true;
776 	}
777 
778 	spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
779 }
780 
hvfb_on_panic(struct notifier_block * nb,unsigned long e,void * p)781 static 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(hdev->channel))
793 		return NOTIFY_DONE;
794 
795 	par->synchronous_fb = true;
796 	if (par->need_docopy)
797 		hvfb_docopy(par, 0, dio_fb_size);
798 	synthvid_update(info, 0, 0, INT_MAX, INT_MAX);
799 
800 	return NOTIFY_DONE;
801 }
802 
803 /* Framebuffer operation handlers */
804 
hvfb_check_var(struct fb_var_screeninfo * var,struct fb_info * info)805 static 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 
hvfb_set_par(struct fb_info * info)818 static 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 
chan_to_field(u32 chan,struct fb_bitfield * bf)826 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
827 {
828 	return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
829 }
830 
hvfb_setcolreg(unsigned regno,unsigned red,unsigned green,unsigned blue,unsigned transp,struct fb_info * info)831 static 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(red, &info->var.red)
840 		| chan_to_field(green, &info->var.green)
841 		| chan_to_field(blue, &info->var.blue)
842 		| chan_to_field(transp, &info->var.transp);
843 
844 	return 0;
845 }
846 
hvfb_blank(int blank,struct fb_info * info)847 static 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 
hvfb_ops_damage_range(struct fb_info * info,off_t off,size_t len)852 static void hvfb_ops_damage_range(struct fb_info *info, off_t off, size_t len)
853 {
854 	/* TODO: implement damage handling */
855 }
856 
hvfb_ops_damage_area(struct fb_info * info,u32 x,u32 y,u32 width,u32 height)857 static 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, 0, 0, INT_MAX, INT_MAX);
863 	else
864 		hvfb_ondemand_refresh_throttle(par, x, y, width, 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  */
hvfb_destroy(struct fb_info * info)872 static 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  */
882 FB_GEN_DEFAULT_DEFERRED_IOMEM_OPS(hvfb_ops,
883 				  hvfb_ops_damage_range,
884 				  hvfb_ops_damage_area)
885 
886 static 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=" */
hvfb_get_option(struct fb_info * info)897 static 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, &opt) || !opt || !*opt)
904 		return;
905 
906 	p = strsep(&opt, "x");
907 	if (!*p || kstrtouint(p, 0, &x) ||
908 	    !opt || !*opt || kstrtouint(opt, 0, &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(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  */
hvfb_get_phymem(struct hv_device * hdev,unsigned int request_size)931 static 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(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(&hdev->device,
955 					  round_up(request_size, PAGE_SIZE),
956 					  &dma_handle,
957 					  GFP_KERNEL | __GFP_NOWARN);
958 
959 		if (!vmem)
960 			return -1;
961 
962 		paddr = virt_to_phys(vmem);
963 	}
964 
965 	return paddr;
966 }
967 
968 /* Release contiguous physical memory */
hvfb_release_phymem(struct device * device,phys_addr_t paddr,unsigned int size)969 static 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(device,
978 				  round_up(size, PAGE_SIZE),
979 				  phys_to_virt(paddr),
980 				  paddr);
981 }
982 
983 
984 /* Get framebuffer memory from Hyper-V video pci space */
hvfb_getmem(struct hv_device * hdev,struct fb_info * info)985 static 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, 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(&par->mem, hdev, 0, -1,
1048 				  screen_fb_size, 0x100000, 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(par->mem->start, 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 
1078 getmem_done:
1079 	if (!gen2vm)
1080 		pci_dev_put(pdev);
1081 
1082 	return 0;
1083 
1084 err3:
1085 	iounmap(fb_virt);
1086 err2:
1087 	vmbus_free_mmio(par->mem->start, screen_fb_size);
1088 	par->mem = NULL;
1089 err1:
1090 	if (!gen2vm)
1091 		pci_dev_put(pdev);
1092 
1093 	return -ENOMEM;
1094 }
1095 
1096 /* Release the framebuffer */
hvfb_putmem(struct fb_info * info)1097 static void hvfb_putmem(struct fb_info *info)
1098 {
1099 	struct hvfb_par *par = info->par;
1100 
1101 	if (par->need_docopy) {
1102 		vfree(par->dio_vp);
1103 		iounmap(par->mmio_vp);
1104 		vmbus_free_mmio(par->mem->start, screen_fb_size);
1105 	} else {
1106 		hvfb_release_phymem(info->device, info->fix.smem_start,
1107 				    screen_fb_size);
1108 	}
1109 
1110 	par->mem = NULL;
1111 }
1112 
1113 
hvfb_probe(struct hv_device * hdev,const struct hv_vmbus_device_id * dev_id)1114 static 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(sizeof(struct hvfb_par), &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(&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(hdev, 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(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(&hdev->device, 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(&panic_notifier_list,
1214 				       &par->hvfb_panic_nb);
1215 
1216 	return 0;
1217 
1218 error:
1219 	fb_deferred_io_cleanup(info);
1220 	hvfb_putmem(info);
1221 error2:
1222 	vmbus_close(hdev->channel);
1223 error1:
1224 	cancel_delayed_work_sync(&par->dwork);
1225 	hv_set_drvdata(hdev, NULL);
1226 	framebuffer_release(info);
1227 	return ret;
1228 }
1229 
hvfb_remove(struct hv_device * hdev)1230 static void hvfb_remove(struct hv_device *hdev)
1231 {
1232 	struct fb_info *info = hv_get_drvdata(hdev);
1233 	struct hvfb_par *par = info->par;
1234 
1235 	atomic_notifier_chain_unregister(&panic_notifier_list,
1236 					 &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(&par->dwork);
1244 
1245 	vmbus_close(hdev->channel);
1246 	hv_set_drvdata(hdev, NULL);
1247 }
1248 
hvfb_suspend(struct hv_device * hdev)1249 static int hvfb_suspend(struct hv_device *hdev)
1250 {
1251 	struct fb_info *info = hv_get_drvdata(hdev);
1252 	struct hvfb_par *par = info->par;
1253 
1254 	console_lock();
1255 
1256 	/* 1 means do suspend */
1257 	fb_set_suspend(info, 1);
1258 
1259 	cancel_delayed_work_sync(&par->dwork);
1260 	cancel_delayed_work_sync(&info->deferred_work);
1261 
1262 	par->update_saved = par->update;
1263 	par->update = false;
1264 	par->fb_ready = false;
1265 
1266 	vmbus_close(hdev->channel);
1267 
1268 	console_unlock();
1269 
1270 	return 0;
1271 }
1272 
hvfb_resume(struct hv_device * hdev)1273 static int hvfb_resume(struct hv_device *hdev)
1274 {
1275 	struct fb_info *info = hv_get_drvdata(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(hdev->channel);
1288 		goto out;
1289 	}
1290 
1291 	par->fb_ready = true;
1292 	par->update = par->update_saved;
1293 
1294 	schedule_delayed_work(&info->deferred_work, info->fbdefio->delay);
1295 	schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
1296 
1297 	/* 0 means do resume */
1298 	fb_set_suspend(info, 0);
1299 
1300 out:
1301 	console_unlock();
1302 
1303 	return ret;
1304 }
1305 
1306 
1307 static 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 
1315 static const struct hv_vmbus_device_id id_table[] = {
1316 	/* Synthetic Video Device GUID */
1317 	{HV_SYNTHVID_GUID},
1318 	{}
1319 };
1320 
1321 MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
1322 MODULE_DEVICE_TABLE(vmbus, id_table);
1323 
1324 static 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 
hvfb_pci_stub_probe(struct pci_dev * pdev,const struct pci_device_id * ent)1336 static int hvfb_pci_stub_probe(struct pci_dev *pdev,
1337 			       const struct pci_device_id *ent)
1338 {
1339 	return 0;
1340 }
1341 
hvfb_pci_stub_remove(struct pci_dev * pdev)1342 static void hvfb_pci_stub_remove(struct pci_dev *pdev)
1343 {
1344 }
1345 
1346 static 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 
hvfb_drv_init(void)1356 static int __init hvfb_drv_init(void)
1357 {
1358 	int ret;
1359 
1360 	if (fb_modesetting_disabled("hyper_fb"))
1361 		return -ENODEV;
1362 
1363 	ret = vmbus_driver_register(&hvfb_drv);
1364 	if (ret != 0)
1365 		return ret;
1366 
1367 	ret = pci_register_driver(&hvfb_pci_stub_driver);
1368 	if (ret != 0) {
1369 		vmbus_driver_unregister(&hvfb_drv);
1370 		return ret;
1371 	}
1372 
1373 	return 0;
1374 }
1375 
hvfb_drv_exit(void)1376 static void __exit hvfb_drv_exit(void)
1377 {
1378 	pci_unregister_driver(&hvfb_pci_stub_driver);
1379 	vmbus_driver_unregister(&hvfb_drv);
1380 }
1381 
1382 module_init(hvfb_drv_init);
1383 module_exit(hvfb_drv_exit);
1384 
1385 MODULE_LICENSE("GPL");
1386 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");
1387