xref: /openbmc/linux/drivers/video/fbdev/hyperv_fb.c (revision afb46f79)
1 /*
2  * Copyright (c) 2012, Microsoft Corporation.
3  *
4  * Author:
5  *   Haiyang Zhang <haiyangz@microsoft.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License version 2 as published
9  * by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
14  * NON INFRINGEMENT.  See the GNU General Public License for more
15  * details.
16  */
17 
18 /*
19  * Hyper-V Synthetic Video Frame Buffer Driver
20  *
21  * This is the driver for the Hyper-V Synthetic Video, which supports
22  * screen resolution up to Full HD 1920x1080 with 32 bit color on Windows
23  * Server 2012, and 1600x1200 with 16 bit color on Windows Server 2008 R2
24  * or earlier.
25  *
26  * It also solves the double mouse cursor issue of the emulated video mode.
27  *
28  * The default screen resolution is 1152x864, which may be changed by a
29  * kernel parameter:
30  *     video=hyperv_fb:<width>x<height>
31  *     For example: video=hyperv_fb:1280x1024
32  *
33  * Portrait orientation is also supported:
34  *     For example: video=hyperv_fb:864x1152
35  */
36 
37 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
38 
39 #include <linux/module.h>
40 #include <linux/kernel.h>
41 #include <linux/init.h>
42 #include <linux/completion.h>
43 #include <linux/fb.h>
44 #include <linux/pci.h>
45 #include <linux/efi.h>
46 
47 #include <linux/hyperv.h>
48 
49 
50 /* Hyper-V Synthetic Video Protocol definitions and structures */
51 #define MAX_VMBUS_PKT_SIZE 0x4000
52 
53 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
54 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
55 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
56 
57 #define SYNTHVID_DEPTH_WIN7 16
58 #define SYNTHVID_DEPTH_WIN8 32
59 
60 #define SYNTHVID_FB_SIZE_WIN7 (4 * 1024 * 1024)
61 #define SYNTHVID_WIDTH_MAX_WIN7 1600
62 #define SYNTHVID_HEIGHT_MAX_WIN7 1200
63 
64 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
65 
66 #define PCI_VENDOR_ID_MICROSOFT 0x1414
67 #define PCI_DEVICE_ID_HYPERV_VIDEO 0x5353
68 
69 
70 enum pipe_msg_type {
71 	PIPE_MSG_INVALID,
72 	PIPE_MSG_DATA,
73 	PIPE_MSG_MAX
74 };
75 
76 struct pipe_msg_hdr {
77 	u32 type;
78 	u32 size; /* size of message after this field */
79 } __packed;
80 
81 
82 enum synthvid_msg_type {
83 	SYNTHVID_ERROR			= 0,
84 	SYNTHVID_VERSION_REQUEST	= 1,
85 	SYNTHVID_VERSION_RESPONSE	= 2,
86 	SYNTHVID_VRAM_LOCATION		= 3,
87 	SYNTHVID_VRAM_LOCATION_ACK	= 4,
88 	SYNTHVID_SITUATION_UPDATE	= 5,
89 	SYNTHVID_SITUATION_UPDATE_ACK	= 6,
90 	SYNTHVID_POINTER_POSITION	= 7,
91 	SYNTHVID_POINTER_SHAPE		= 8,
92 	SYNTHVID_FEATURE_CHANGE		= 9,
93 	SYNTHVID_DIRT			= 10,
94 
95 	SYNTHVID_MAX			= 11
96 };
97 
98 struct synthvid_msg_hdr {
99 	u32 type;
100 	u32 size;  /* size of this header + payload after this field*/
101 } __packed;
102 
103 
104 struct synthvid_version_req {
105 	u32 version;
106 } __packed;
107 
108 struct synthvid_version_resp {
109 	u32 version;
110 	u8 is_accepted;
111 	u8 max_video_outputs;
112 } __packed;
113 
114 struct synthvid_vram_location {
115 	u64 user_ctx;
116 	u8 is_vram_gpa_specified;
117 	u64 vram_gpa;
118 } __packed;
119 
120 struct synthvid_vram_location_ack {
121 	u64 user_ctx;
122 } __packed;
123 
124 struct video_output_situation {
125 	u8 active;
126 	u32 vram_offset;
127 	u8 depth_bits;
128 	u32 width_pixels;
129 	u32 height_pixels;
130 	u32 pitch_bytes;
131 } __packed;
132 
133 struct synthvid_situation_update {
134 	u64 user_ctx;
135 	u8 video_output_count;
136 	struct video_output_situation video_output[1];
137 } __packed;
138 
139 struct synthvid_situation_update_ack {
140 	u64 user_ctx;
141 } __packed;
142 
143 struct synthvid_pointer_position {
144 	u8 is_visible;
145 	u8 video_output;
146 	s32 image_x;
147 	s32 image_y;
148 } __packed;
149 
150 
151 #define CURSOR_MAX_X 96
152 #define CURSOR_MAX_Y 96
153 #define CURSOR_ARGB_PIXEL_SIZE 4
154 #define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE)
155 #define CURSOR_COMPLETE (-1)
156 
157 struct synthvid_pointer_shape {
158 	u8 part_idx;
159 	u8 is_argb;
160 	u32 width; /* CURSOR_MAX_X at most */
161 	u32 height; /* CURSOR_MAX_Y at most */
162 	u32 hot_x; /* hotspot relative to upper-left of pointer image */
163 	u32 hot_y;
164 	u8 data[4];
165 } __packed;
166 
167 struct synthvid_feature_change {
168 	u8 is_dirt_needed;
169 	u8 is_ptr_pos_needed;
170 	u8 is_ptr_shape_needed;
171 	u8 is_situ_needed;
172 } __packed;
173 
174 struct rect {
175 	s32 x1, y1; /* top left corner */
176 	s32 x2, y2; /* bottom right corner, exclusive */
177 } __packed;
178 
179 struct synthvid_dirt {
180 	u8 video_output;
181 	u8 dirt_count;
182 	struct rect rect[1];
183 } __packed;
184 
185 struct synthvid_msg {
186 	struct pipe_msg_hdr pipe_hdr;
187 	struct synthvid_msg_hdr vid_hdr;
188 	union {
189 		struct synthvid_version_req ver_req;
190 		struct synthvid_version_resp ver_resp;
191 		struct synthvid_vram_location vram;
192 		struct synthvid_vram_location_ack vram_ack;
193 		struct synthvid_situation_update situ;
194 		struct synthvid_situation_update_ack situ_ack;
195 		struct synthvid_pointer_position ptr_pos;
196 		struct synthvid_pointer_shape ptr_shape;
197 		struct synthvid_feature_change feature_chg;
198 		struct synthvid_dirt dirt;
199 	};
200 } __packed;
201 
202 
203 
204 /* FB driver definitions and structures */
205 #define HVFB_WIDTH 1152 /* default screen width */
206 #define HVFB_HEIGHT 864 /* default screen height */
207 #define HVFB_WIDTH_MIN 640
208 #define HVFB_HEIGHT_MIN 480
209 
210 #define RING_BUFSIZE (256 * 1024)
211 #define VSP_TIMEOUT (10 * HZ)
212 #define HVFB_UPDATE_DELAY (HZ / 20)
213 
214 struct hvfb_par {
215 	struct fb_info *info;
216 	struct resource mem;
217 	bool fb_ready; /* fb device is ready */
218 	struct completion wait;
219 	u32 synthvid_version;
220 
221 	struct delayed_work dwork;
222 	bool update;
223 
224 	u32 pseudo_palette[16];
225 	u8 init_buf[MAX_VMBUS_PKT_SIZE];
226 	u8 recv_buf[MAX_VMBUS_PKT_SIZE];
227 };
228 
229 static uint screen_width = HVFB_WIDTH;
230 static uint screen_height = HVFB_HEIGHT;
231 static uint screen_depth;
232 static uint screen_fb_size;
233 
234 /* Send message to Hyper-V host */
235 static inline int synthvid_send(struct hv_device *hdev,
236 				struct synthvid_msg *msg)
237 {
238 	static atomic64_t request_id = ATOMIC64_INIT(0);
239 	int ret;
240 
241 	msg->pipe_hdr.type = PIPE_MSG_DATA;
242 	msg->pipe_hdr.size = msg->vid_hdr.size;
243 
244 	ret = vmbus_sendpacket(hdev->channel, msg,
245 			       msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
246 			       atomic64_inc_return(&request_id),
247 			       VM_PKT_DATA_INBAND, 0);
248 
249 	if (ret)
250 		pr_err("Unable to send packet via vmbus\n");
251 
252 	return ret;
253 }
254 
255 
256 /* Send screen resolution info to host */
257 static int synthvid_send_situ(struct hv_device *hdev)
258 {
259 	struct fb_info *info = hv_get_drvdata(hdev);
260 	struct synthvid_msg msg;
261 
262 	if (!info)
263 		return -ENODEV;
264 
265 	memset(&msg, 0, sizeof(struct synthvid_msg));
266 
267 	msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
268 	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
269 		sizeof(struct synthvid_situation_update);
270 	msg.situ.user_ctx = 0;
271 	msg.situ.video_output_count = 1;
272 	msg.situ.video_output[0].active = 1;
273 	msg.situ.video_output[0].vram_offset = 0;
274 	msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
275 	msg.situ.video_output[0].width_pixels = info->var.xres;
276 	msg.situ.video_output[0].height_pixels = info->var.yres;
277 	msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
278 
279 	synthvid_send(hdev, &msg);
280 
281 	return 0;
282 }
283 
284 /* Send mouse pointer info to host */
285 static int synthvid_send_ptr(struct hv_device *hdev)
286 {
287 	struct synthvid_msg msg;
288 
289 	memset(&msg, 0, sizeof(struct synthvid_msg));
290 	msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
291 	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
292 		sizeof(struct synthvid_pointer_position);
293 	msg.ptr_pos.is_visible = 1;
294 	msg.ptr_pos.video_output = 0;
295 	msg.ptr_pos.image_x = 0;
296 	msg.ptr_pos.image_y = 0;
297 	synthvid_send(hdev, &msg);
298 
299 	memset(&msg, 0, sizeof(struct synthvid_msg));
300 	msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
301 	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
302 		sizeof(struct synthvid_pointer_shape);
303 	msg.ptr_shape.part_idx = CURSOR_COMPLETE;
304 	msg.ptr_shape.is_argb = 1;
305 	msg.ptr_shape.width = 1;
306 	msg.ptr_shape.height = 1;
307 	msg.ptr_shape.hot_x = 0;
308 	msg.ptr_shape.hot_y = 0;
309 	msg.ptr_shape.data[0] = 0;
310 	msg.ptr_shape.data[1] = 1;
311 	msg.ptr_shape.data[2] = 1;
312 	msg.ptr_shape.data[3] = 1;
313 	synthvid_send(hdev, &msg);
314 
315 	return 0;
316 }
317 
318 /* Send updated screen area (dirty rectangle) location to host */
319 static int synthvid_update(struct fb_info *info)
320 {
321 	struct hv_device *hdev = device_to_hv_device(info->device);
322 	struct synthvid_msg msg;
323 
324 	memset(&msg, 0, sizeof(struct synthvid_msg));
325 
326 	msg.vid_hdr.type = SYNTHVID_DIRT;
327 	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
328 		sizeof(struct synthvid_dirt);
329 	msg.dirt.video_output = 0;
330 	msg.dirt.dirt_count = 1;
331 	msg.dirt.rect[0].x1 = 0;
332 	msg.dirt.rect[0].y1 = 0;
333 	msg.dirt.rect[0].x2 = info->var.xres;
334 	msg.dirt.rect[0].y2 = info->var.yres;
335 
336 	synthvid_send(hdev, &msg);
337 
338 	return 0;
339 }
340 
341 
342 /*
343  * Actions on received messages from host:
344  * Complete the wait event.
345  * Or, reply with screen and cursor info.
346  */
347 static void synthvid_recv_sub(struct hv_device *hdev)
348 {
349 	struct fb_info *info = hv_get_drvdata(hdev);
350 	struct hvfb_par *par;
351 	struct synthvid_msg *msg;
352 
353 	if (!info)
354 		return;
355 
356 	par = info->par;
357 	msg = (struct synthvid_msg *)par->recv_buf;
358 
359 	/* Complete the wait event */
360 	if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
361 	    msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
362 		memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
363 		complete(&par->wait);
364 		return;
365 	}
366 
367 	/* Reply with screen and cursor info */
368 	if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
369 		if (par->fb_ready) {
370 			synthvid_send_ptr(hdev);
371 			synthvid_send_situ(hdev);
372 		}
373 
374 		par->update = msg->feature_chg.is_dirt_needed;
375 		if (par->update)
376 			schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
377 	}
378 }
379 
380 /* Receive callback for messages from the host */
381 static void synthvid_receive(void *ctx)
382 {
383 	struct hv_device *hdev = ctx;
384 	struct fb_info *info = hv_get_drvdata(hdev);
385 	struct hvfb_par *par;
386 	struct synthvid_msg *recv_buf;
387 	u32 bytes_recvd;
388 	u64 req_id;
389 	int ret;
390 
391 	if (!info)
392 		return;
393 
394 	par = info->par;
395 	recv_buf = (struct synthvid_msg *)par->recv_buf;
396 
397 	do {
398 		ret = vmbus_recvpacket(hdev->channel, recv_buf,
399 				       MAX_VMBUS_PKT_SIZE,
400 				       &bytes_recvd, &req_id);
401 		if (bytes_recvd > 0 &&
402 		    recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
403 			synthvid_recv_sub(hdev);
404 	} while (bytes_recvd > 0 && ret == 0);
405 }
406 
407 /* Check synthetic video protocol version with the host */
408 static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
409 {
410 	struct fb_info *info = hv_get_drvdata(hdev);
411 	struct hvfb_par *par = info->par;
412 	struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
413 	int t, ret = 0;
414 
415 	memset(msg, 0, sizeof(struct synthvid_msg));
416 	msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
417 	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
418 		sizeof(struct synthvid_version_req);
419 	msg->ver_req.version = ver;
420 	synthvid_send(hdev, msg);
421 
422 	t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
423 	if (!t) {
424 		pr_err("Time out on waiting version response\n");
425 		ret = -ETIMEDOUT;
426 		goto out;
427 	}
428 	if (!msg->ver_resp.is_accepted) {
429 		ret = -ENODEV;
430 		goto out;
431 	}
432 
433 	par->synthvid_version = ver;
434 
435 out:
436 	return ret;
437 }
438 
439 /* Connect to VSP (Virtual Service Provider) on host */
440 static int synthvid_connect_vsp(struct hv_device *hdev)
441 {
442 	struct fb_info *info = hv_get_drvdata(hdev);
443 	struct hvfb_par *par = info->par;
444 	int ret;
445 
446 	ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
447 			 NULL, 0, synthvid_receive, hdev);
448 	if (ret) {
449 		pr_err("Unable to open vmbus channel\n");
450 		return ret;
451 	}
452 
453 	/* Negotiate the protocol version with host */
454 	if (vmbus_proto_version == VERSION_WS2008 ||
455 	    vmbus_proto_version == VERSION_WIN7)
456 		ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN7);
457 	else
458 		ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
459 
460 	if (ret) {
461 		pr_err("Synthetic video device version not accepted\n");
462 		goto error;
463 	}
464 
465 	if (par->synthvid_version == SYNTHVID_VERSION_WIN7)
466 		screen_depth = SYNTHVID_DEPTH_WIN7;
467 	else
468 		screen_depth = SYNTHVID_DEPTH_WIN8;
469 
470 	screen_fb_size = hdev->channel->offermsg.offer.
471 				mmio_megabytes * 1024 * 1024;
472 
473 	return 0;
474 
475 error:
476 	vmbus_close(hdev->channel);
477 	return ret;
478 }
479 
480 /* Send VRAM and Situation messages to the host */
481 static int synthvid_send_config(struct hv_device *hdev)
482 {
483 	struct fb_info *info = hv_get_drvdata(hdev);
484 	struct hvfb_par *par = info->par;
485 	struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
486 	int t, ret = 0;
487 
488 	/* Send VRAM location */
489 	memset(msg, 0, sizeof(struct synthvid_msg));
490 	msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
491 	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
492 		sizeof(struct synthvid_vram_location);
493 	msg->vram.user_ctx = msg->vram.vram_gpa = info->fix.smem_start;
494 	msg->vram.is_vram_gpa_specified = 1;
495 	synthvid_send(hdev, msg);
496 
497 	t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
498 	if (!t) {
499 		pr_err("Time out on waiting vram location ack\n");
500 		ret = -ETIMEDOUT;
501 		goto out;
502 	}
503 	if (msg->vram_ack.user_ctx != info->fix.smem_start) {
504 		pr_err("Unable to set VRAM location\n");
505 		ret = -ENODEV;
506 		goto out;
507 	}
508 
509 	/* Send pointer and situation update */
510 	synthvid_send_ptr(hdev);
511 	synthvid_send_situ(hdev);
512 
513 out:
514 	return ret;
515 }
516 
517 
518 /*
519  * Delayed work callback:
520  * It is called at HVFB_UPDATE_DELAY or longer time interval to process
521  * screen updates. It is re-scheduled if further update is necessary.
522  */
523 static void hvfb_update_work(struct work_struct *w)
524 {
525 	struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
526 	struct fb_info *info = par->info;
527 
528 	if (par->fb_ready)
529 		synthvid_update(info);
530 
531 	if (par->update)
532 		schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
533 }
534 
535 
536 /* Framebuffer operation handlers */
537 
538 static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
539 {
540 	if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
541 	    var->xres > screen_width || var->yres >  screen_height ||
542 	    var->bits_per_pixel != screen_depth)
543 		return -EINVAL;
544 
545 	var->xres_virtual = var->xres;
546 	var->yres_virtual = var->yres;
547 
548 	return 0;
549 }
550 
551 static int hvfb_set_par(struct fb_info *info)
552 {
553 	struct hv_device *hdev = device_to_hv_device(info->device);
554 
555 	return synthvid_send_situ(hdev);
556 }
557 
558 
559 static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
560 {
561 	return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
562 }
563 
564 static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
565 			  unsigned blue, unsigned transp, struct fb_info *info)
566 {
567 	u32 *pal = info->pseudo_palette;
568 
569 	if (regno > 15)
570 		return -EINVAL;
571 
572 	pal[regno] = chan_to_field(red, &info->var.red)
573 		| chan_to_field(green, &info->var.green)
574 		| chan_to_field(blue, &info->var.blue)
575 		| chan_to_field(transp, &info->var.transp);
576 
577 	return 0;
578 }
579 
580 static int hvfb_blank(int blank, struct fb_info *info)
581 {
582 	return 1;	/* get fb_blank to set the colormap to all black */
583 }
584 
585 static struct fb_ops hvfb_ops = {
586 	.owner = THIS_MODULE,
587 	.fb_check_var = hvfb_check_var,
588 	.fb_set_par = hvfb_set_par,
589 	.fb_setcolreg = hvfb_setcolreg,
590 	.fb_fillrect = cfb_fillrect,
591 	.fb_copyarea = cfb_copyarea,
592 	.fb_imageblit = cfb_imageblit,
593 	.fb_blank = hvfb_blank,
594 };
595 
596 
597 /* Get options from kernel paramenter "video=" */
598 static void hvfb_get_option(struct fb_info *info)
599 {
600 	struct hvfb_par *par = info->par;
601 	char *opt = NULL, *p;
602 	uint x = 0, y = 0;
603 
604 	if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
605 		return;
606 
607 	p = strsep(&opt, "x");
608 	if (!*p || kstrtouint(p, 0, &x) ||
609 	    !opt || !*opt || kstrtouint(opt, 0, &y)) {
610 		pr_err("Screen option is invalid: skipped\n");
611 		return;
612 	}
613 
614 	if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
615 	    (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
616 	     x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8) ||
617 	    (par->synthvid_version == SYNTHVID_VERSION_WIN7 &&
618 	     (x > SYNTHVID_WIDTH_MAX_WIN7 || y > SYNTHVID_HEIGHT_MAX_WIN7))) {
619 		pr_err("Screen resolution option is out of range: skipped\n");
620 		return;
621 	}
622 
623 	screen_width = x;
624 	screen_height = y;
625 	return;
626 }
627 
628 
629 /* Get framebuffer memory from Hyper-V video pci space */
630 static int hvfb_getmem(struct fb_info *info)
631 {
632 	struct hvfb_par *par = info->par;
633 	struct pci_dev *pdev  = NULL;
634 	void __iomem *fb_virt;
635 	int gen2vm = efi_enabled(EFI_BOOT);
636 	int ret;
637 
638 	par->mem.name = KBUILD_MODNAME;
639 	par->mem.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
640 	if (gen2vm) {
641 		ret = allocate_resource(&hyperv_mmio, &par->mem,
642 					screen_fb_size,
643 					0, -1,
644 					screen_fb_size,
645 					NULL, NULL);
646 		if (ret != 0) {
647 			pr_err("Unable to allocate framebuffer memory\n");
648 			return -ENODEV;
649 		}
650 	} else {
651 		pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
652 			      PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
653 		if (!pdev) {
654 			pr_err("Unable to find PCI Hyper-V video\n");
655 			return -ENODEV;
656 		}
657 
658 		if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
659 		    pci_resource_len(pdev, 0) < screen_fb_size)
660 			goto err1;
661 
662 		par->mem.end = pci_resource_end(pdev, 0);
663 		par->mem.start = par->mem.end - screen_fb_size + 1;
664 		ret = request_resource(&pdev->resource[0], &par->mem);
665 		if (ret != 0) {
666 			pr_err("Unable to request framebuffer memory\n");
667 			goto err1;
668 		}
669 	}
670 
671 	fb_virt = ioremap(par->mem.start, screen_fb_size);
672 	if (!fb_virt)
673 		goto err2;
674 
675 	info->apertures = alloc_apertures(1);
676 	if (!info->apertures)
677 		goto err3;
678 
679 	if (gen2vm) {
680 		info->apertures->ranges[0].base = screen_info.lfb_base;
681 		info->apertures->ranges[0].size = screen_info.lfb_size;
682 		remove_conflicting_framebuffers(info->apertures,
683 						KBUILD_MODNAME, false);
684 	} else {
685 		info->apertures->ranges[0].base = pci_resource_start(pdev, 0);
686 		info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
687 	}
688 
689 	info->fix.smem_start = par->mem.start;
690 	info->fix.smem_len = screen_fb_size;
691 	info->screen_base = fb_virt;
692 	info->screen_size = screen_fb_size;
693 
694 	if (!gen2vm)
695 		pci_dev_put(pdev);
696 
697 	return 0;
698 
699 err3:
700 	iounmap(fb_virt);
701 err2:
702 	release_resource(&par->mem);
703 err1:
704 	if (!gen2vm)
705 		pci_dev_put(pdev);
706 
707 	return -ENOMEM;
708 }
709 
710 /* Release the framebuffer */
711 static void hvfb_putmem(struct fb_info *info)
712 {
713 	struct hvfb_par *par = info->par;
714 
715 	iounmap(info->screen_base);
716 	release_resource(&par->mem);
717 }
718 
719 
720 static int hvfb_probe(struct hv_device *hdev,
721 		      const struct hv_vmbus_device_id *dev_id)
722 {
723 	struct fb_info *info;
724 	struct hvfb_par *par;
725 	int ret;
726 
727 	info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
728 	if (!info) {
729 		pr_err("No memory for framebuffer info\n");
730 		return -ENOMEM;
731 	}
732 
733 	par = info->par;
734 	par->info = info;
735 	par->fb_ready = false;
736 	init_completion(&par->wait);
737 	INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
738 
739 	/* Connect to VSP */
740 	hv_set_drvdata(hdev, info);
741 	ret = synthvid_connect_vsp(hdev);
742 	if (ret) {
743 		pr_err("Unable to connect to VSP\n");
744 		goto error1;
745 	}
746 
747 	ret = hvfb_getmem(info);
748 	if (ret) {
749 		pr_err("No memory for framebuffer\n");
750 		goto error2;
751 	}
752 
753 	hvfb_get_option(info);
754 	pr_info("Screen resolution: %dx%d, Color depth: %d\n",
755 		screen_width, screen_height, screen_depth);
756 
757 
758 	/* Set up fb_info */
759 	info->flags = FBINFO_DEFAULT;
760 
761 	info->var.xres_virtual = info->var.xres = screen_width;
762 	info->var.yres_virtual = info->var.yres = screen_height;
763 	info->var.bits_per_pixel = screen_depth;
764 
765 	if (info->var.bits_per_pixel == 16) {
766 		info->var.red = (struct fb_bitfield){11, 5, 0};
767 		info->var.green = (struct fb_bitfield){5, 6, 0};
768 		info->var.blue = (struct fb_bitfield){0, 5, 0};
769 		info->var.transp = (struct fb_bitfield){0, 0, 0};
770 	} else {
771 		info->var.red = (struct fb_bitfield){16, 8, 0};
772 		info->var.green = (struct fb_bitfield){8, 8, 0};
773 		info->var.blue = (struct fb_bitfield){0, 8, 0};
774 		info->var.transp = (struct fb_bitfield){24, 8, 0};
775 	}
776 
777 	info->var.activate = FB_ACTIVATE_NOW;
778 	info->var.height = -1;
779 	info->var.width = -1;
780 	info->var.vmode = FB_VMODE_NONINTERLACED;
781 
782 	strcpy(info->fix.id, KBUILD_MODNAME);
783 	info->fix.type = FB_TYPE_PACKED_PIXELS;
784 	info->fix.visual = FB_VISUAL_TRUECOLOR;
785 	info->fix.line_length = screen_width * screen_depth / 8;
786 	info->fix.accel = FB_ACCEL_NONE;
787 
788 	info->fbops = &hvfb_ops;
789 	info->pseudo_palette = par->pseudo_palette;
790 
791 	/* Send config to host */
792 	ret = synthvid_send_config(hdev);
793 	if (ret)
794 		goto error;
795 
796 	ret = register_framebuffer(info);
797 	if (ret) {
798 		pr_err("Unable to register framebuffer\n");
799 		goto error;
800 	}
801 
802 	par->fb_ready = true;
803 
804 	return 0;
805 
806 error:
807 	hvfb_putmem(info);
808 error2:
809 	vmbus_close(hdev->channel);
810 error1:
811 	cancel_delayed_work_sync(&par->dwork);
812 	hv_set_drvdata(hdev, NULL);
813 	framebuffer_release(info);
814 	return ret;
815 }
816 
817 
818 static int hvfb_remove(struct hv_device *hdev)
819 {
820 	struct fb_info *info = hv_get_drvdata(hdev);
821 	struct hvfb_par *par = info->par;
822 
823 	par->update = false;
824 	par->fb_ready = false;
825 
826 	unregister_framebuffer(info);
827 	cancel_delayed_work_sync(&par->dwork);
828 
829 	vmbus_close(hdev->channel);
830 	hv_set_drvdata(hdev, NULL);
831 
832 	hvfb_putmem(info);
833 	framebuffer_release(info);
834 
835 	return 0;
836 }
837 
838 
839 static DEFINE_PCI_DEVICE_TABLE(pci_stub_id_table) = {
840 	{
841 		.vendor      = PCI_VENDOR_ID_MICROSOFT,
842 		.device      = PCI_DEVICE_ID_HYPERV_VIDEO,
843 	},
844 	{ /* end of list */ }
845 };
846 
847 static const struct hv_vmbus_device_id id_table[] = {
848 	/* Synthetic Video Device GUID */
849 	{HV_SYNTHVID_GUID},
850 	{}
851 };
852 
853 MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
854 MODULE_DEVICE_TABLE(vmbus, id_table);
855 
856 static struct hv_driver hvfb_drv = {
857 	.name = KBUILD_MODNAME,
858 	.id_table = id_table,
859 	.probe = hvfb_probe,
860 	.remove = hvfb_remove,
861 };
862 
863 static int hvfb_pci_stub_probe(struct pci_dev *pdev,
864 			       const struct pci_device_id *ent)
865 {
866 	return 0;
867 }
868 
869 static void hvfb_pci_stub_remove(struct pci_dev *pdev)
870 {
871 }
872 
873 static struct pci_driver hvfb_pci_stub_driver = {
874 	.name =		KBUILD_MODNAME,
875 	.id_table =	pci_stub_id_table,
876 	.probe =	hvfb_pci_stub_probe,
877 	.remove =	hvfb_pci_stub_remove,
878 };
879 
880 static int __init hvfb_drv_init(void)
881 {
882 	int ret;
883 
884 	ret = vmbus_driver_register(&hvfb_drv);
885 	if (ret != 0)
886 		return ret;
887 
888 	ret = pci_register_driver(&hvfb_pci_stub_driver);
889 	if (ret != 0) {
890 		vmbus_driver_unregister(&hvfb_drv);
891 		return ret;
892 	}
893 
894 	return 0;
895 }
896 
897 static void __exit hvfb_drv_exit(void)
898 {
899 	pci_unregister_driver(&hvfb_pci_stub_driver);
900 	vmbus_driver_unregister(&hvfb_drv);
901 }
902 
903 module_init(hvfb_drv_init);
904 module_exit(hvfb_drv_exit);
905 
906 MODULE_LICENSE("GPL");
907 MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");
908