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
70enum pipe_msg_type {
71	PIPE_MSG_INVALID,
72	PIPE_MSG_DATA,
73	PIPE_MSG_MAX
74};
75
76struct pipe_msg_hdr {
77	u32 type;
78	u32 size; /* size of message after this field */
79} __packed;
80
81
82enum 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
98struct synthvid_msg_hdr {
99	u32 type;
100	u32 size;  /* size of this header + payload after this field*/
101} __packed;
102
103
104struct synthvid_version_req {
105	u32 version;
106} __packed;
107
108struct synthvid_version_resp {
109	u32 version;
110	u8 is_accepted;
111	u8 max_video_outputs;
112} __packed;
113
114struct synthvid_vram_location {
115	u64 user_ctx;
116	u8 is_vram_gpa_specified;
117	u64 vram_gpa;
118} __packed;
119
120struct synthvid_vram_location_ack {
121	u64 user_ctx;
122} __packed;
123
124struct 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
133struct synthvid_situation_update {
134	u64 user_ctx;
135	u8 video_output_count;
136	struct video_output_situation video_output[1];
137} __packed;
138
139struct synthvid_situation_update_ack {
140	u64 user_ctx;
141} __packed;
142
143struct 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
157struct 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
167struct 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
174struct rect {
175	s32 x1, y1; /* top left corner */
176	s32 x2, y2; /* bottom right corner, exclusive */
177} __packed;
178
179struct synthvid_dirt {
180	u8 video_output;
181	u8 dirt_count;
182	struct rect rect[1];
183} __packed;
184
185struct 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
214struct 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	/* If true, the VSC notifies the VSP on every framebuffer change */
229	bool synchronous_fb;
230
231	struct notifier_block hvfb_panic_nb;
232};
233
234static uint screen_width = HVFB_WIDTH;
235static uint screen_height = HVFB_HEIGHT;
236static uint screen_depth;
237static uint screen_fb_size;
238
239/* Send message to Hyper-V host */
240static inline int synthvid_send(struct hv_device *hdev,
241				struct synthvid_msg *msg)
242{
243	static atomic64_t request_id = ATOMIC64_INIT(0);
244	int ret;
245
246	msg->pipe_hdr.type = PIPE_MSG_DATA;
247	msg->pipe_hdr.size = msg->vid_hdr.size;
248
249	ret = vmbus_sendpacket(hdev->channel, msg,
250			       msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
251			       atomic64_inc_return(&request_id),
252			       VM_PKT_DATA_INBAND, 0);
253
254	if (ret)
255		pr_err("Unable to send packet via vmbus\n");
256
257	return ret;
258}
259
260
261/* Send screen resolution info to host */
262static int synthvid_send_situ(struct hv_device *hdev)
263{
264	struct fb_info *info = hv_get_drvdata(hdev);
265	struct synthvid_msg msg;
266
267	if (!info)
268		return -ENODEV;
269
270	memset(&msg, 0, sizeof(struct synthvid_msg));
271
272	msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
273	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
274		sizeof(struct synthvid_situation_update);
275	msg.situ.user_ctx = 0;
276	msg.situ.video_output_count = 1;
277	msg.situ.video_output[0].active = 1;
278	msg.situ.video_output[0].vram_offset = 0;
279	msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
280	msg.situ.video_output[0].width_pixels = info->var.xres;
281	msg.situ.video_output[0].height_pixels = info->var.yres;
282	msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
283
284	synthvid_send(hdev, &msg);
285
286	return 0;
287}
288
289/* Send mouse pointer info to host */
290static int synthvid_send_ptr(struct hv_device *hdev)
291{
292	struct synthvid_msg msg;
293
294	memset(&msg, 0, sizeof(struct synthvid_msg));
295	msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
296	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
297		sizeof(struct synthvid_pointer_position);
298	msg.ptr_pos.is_visible = 1;
299	msg.ptr_pos.video_output = 0;
300	msg.ptr_pos.image_x = 0;
301	msg.ptr_pos.image_y = 0;
302	synthvid_send(hdev, &msg);
303
304	memset(&msg, 0, sizeof(struct synthvid_msg));
305	msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
306	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
307		sizeof(struct synthvid_pointer_shape);
308	msg.ptr_shape.part_idx = CURSOR_COMPLETE;
309	msg.ptr_shape.is_argb = 1;
310	msg.ptr_shape.width = 1;
311	msg.ptr_shape.height = 1;
312	msg.ptr_shape.hot_x = 0;
313	msg.ptr_shape.hot_y = 0;
314	msg.ptr_shape.data[0] = 0;
315	msg.ptr_shape.data[1] = 1;
316	msg.ptr_shape.data[2] = 1;
317	msg.ptr_shape.data[3] = 1;
318	synthvid_send(hdev, &msg);
319
320	return 0;
321}
322
323/* Send updated screen area (dirty rectangle) location to host */
324static int synthvid_update(struct fb_info *info)
325{
326	struct hv_device *hdev = device_to_hv_device(info->device);
327	struct synthvid_msg msg;
328
329	memset(&msg, 0, sizeof(struct synthvid_msg));
330
331	msg.vid_hdr.type = SYNTHVID_DIRT;
332	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
333		sizeof(struct synthvid_dirt);
334	msg.dirt.video_output = 0;
335	msg.dirt.dirt_count = 1;
336	msg.dirt.rect[0].x1 = 0;
337	msg.dirt.rect[0].y1 = 0;
338	msg.dirt.rect[0].x2 = info->var.xres;
339	msg.dirt.rect[0].y2 = info->var.yres;
340
341	synthvid_send(hdev, &msg);
342
343	return 0;
344}
345
346
347/*
348 * Actions on received messages from host:
349 * Complete the wait event.
350 * Or, reply with screen and cursor info.
351 */
352static void synthvid_recv_sub(struct hv_device *hdev)
353{
354	struct fb_info *info = hv_get_drvdata(hdev);
355	struct hvfb_par *par;
356	struct synthvid_msg *msg;
357
358	if (!info)
359		return;
360
361	par = info->par;
362	msg = (struct synthvid_msg *)par->recv_buf;
363
364	/* Complete the wait event */
365	if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
366	    msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
367		memcpy(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
368		complete(&par->wait);
369		return;
370	}
371
372	/* Reply with screen and cursor info */
373	if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
374		if (par->fb_ready) {
375			synthvid_send_ptr(hdev);
376			synthvid_send_situ(hdev);
377		}
378
379		par->update = msg->feature_chg.is_dirt_needed;
380		if (par->update)
381			schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
382	}
383}
384
385/* Receive callback for messages from the host */
386static void synthvid_receive(void *ctx)
387{
388	struct hv_device *hdev = ctx;
389	struct fb_info *info = hv_get_drvdata(hdev);
390	struct hvfb_par *par;
391	struct synthvid_msg *recv_buf;
392	u32 bytes_recvd;
393	u64 req_id;
394	int ret;
395
396	if (!info)
397		return;
398
399	par = info->par;
400	recv_buf = (struct synthvid_msg *)par->recv_buf;
401
402	do {
403		ret = vmbus_recvpacket(hdev->channel, recv_buf,
404				       MAX_VMBUS_PKT_SIZE,
405				       &bytes_recvd, &req_id);
406		if (bytes_recvd > 0 &&
407		    recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
408			synthvid_recv_sub(hdev);
409	} while (bytes_recvd > 0 && ret == 0);
410}
411
412/* Check synthetic video protocol version with the host */
413static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
414{
415	struct fb_info *info = hv_get_drvdata(hdev);
416	struct hvfb_par *par = info->par;
417	struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
418	int ret = 0;
419	unsigned long t;
420
421	memset(msg, 0, sizeof(struct synthvid_msg));
422	msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
423	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
424		sizeof(struct synthvid_version_req);
425	msg->ver_req.version = ver;
426	synthvid_send(hdev, msg);
427
428	t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
429	if (!t) {
430		pr_err("Time out on waiting version response\n");
431		ret = -ETIMEDOUT;
432		goto out;
433	}
434	if (!msg->ver_resp.is_accepted) {
435		ret = -ENODEV;
436		goto out;
437	}
438
439	par->synthvid_version = ver;
440
441out:
442	return ret;
443}
444
445/* Connect to VSP (Virtual Service Provider) on host */
446static int synthvid_connect_vsp(struct hv_device *hdev)
447{
448	struct fb_info *info = hv_get_drvdata(hdev);
449	struct hvfb_par *par = info->par;
450	int ret;
451
452	ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
453			 NULL, 0, synthvid_receive, hdev);
454	if (ret) {
455		pr_err("Unable to open vmbus channel\n");
456		return ret;
457	}
458
459	/* Negotiate the protocol version with host */
460	if (vmbus_proto_version == VERSION_WS2008 ||
461	    vmbus_proto_version == VERSION_WIN7)
462		ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN7);
463	else
464		ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
465
466	if (ret) {
467		pr_err("Synthetic video device version not accepted\n");
468		goto error;
469	}
470
471	if (par->synthvid_version == SYNTHVID_VERSION_WIN7)
472		screen_depth = SYNTHVID_DEPTH_WIN7;
473	else
474		screen_depth = SYNTHVID_DEPTH_WIN8;
475
476	screen_fb_size = hdev->channel->offermsg.offer.
477				mmio_megabytes * 1024 * 1024;
478
479	return 0;
480
481error:
482	vmbus_close(hdev->channel);
483	return ret;
484}
485
486/* Send VRAM and Situation messages to the host */
487static int synthvid_send_config(struct hv_device *hdev)
488{
489	struct fb_info *info = hv_get_drvdata(hdev);
490	struct hvfb_par *par = info->par;
491	struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
492	int ret = 0;
493	unsigned long t;
494
495	/* Send VRAM location */
496	memset(msg, 0, sizeof(struct synthvid_msg));
497	msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
498	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
499		sizeof(struct synthvid_vram_location);
500	msg->vram.user_ctx = msg->vram.vram_gpa = info->fix.smem_start;
501	msg->vram.is_vram_gpa_specified = 1;
502	synthvid_send(hdev, msg);
503
504	t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
505	if (!t) {
506		pr_err("Time out on waiting vram location ack\n");
507		ret = -ETIMEDOUT;
508		goto out;
509	}
510	if (msg->vram_ack.user_ctx != info->fix.smem_start) {
511		pr_err("Unable to set VRAM location\n");
512		ret = -ENODEV;
513		goto out;
514	}
515
516	/* Send pointer and situation update */
517	synthvid_send_ptr(hdev);
518	synthvid_send_situ(hdev);
519
520out:
521	return ret;
522}
523
524
525/*
526 * Delayed work callback:
527 * It is called at HVFB_UPDATE_DELAY or longer time interval to process
528 * screen updates. It is re-scheduled if further update is necessary.
529 */
530static void hvfb_update_work(struct work_struct *w)
531{
532	struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
533	struct fb_info *info = par->info;
534
535	if (par->fb_ready)
536		synthvid_update(info);
537
538	if (par->update)
539		schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
540}
541
542static int hvfb_on_panic(struct notifier_block *nb,
543			 unsigned long e, void *p)
544{
545	struct hvfb_par *par;
546	struct fb_info *info;
547
548	par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
549	par->synchronous_fb = true;
550	info = par->info;
551	synthvid_update(info);
552
553	return NOTIFY_DONE;
554}
555
556/* Framebuffer operation handlers */
557
558static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
559{
560	if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
561	    var->xres > screen_width || var->yres >  screen_height ||
562	    var->bits_per_pixel != screen_depth)
563		return -EINVAL;
564
565	var->xres_virtual = var->xres;
566	var->yres_virtual = var->yres;
567
568	return 0;
569}
570
571static int hvfb_set_par(struct fb_info *info)
572{
573	struct hv_device *hdev = device_to_hv_device(info->device);
574
575	return synthvid_send_situ(hdev);
576}
577
578
579static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
580{
581	return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
582}
583
584static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
585			  unsigned blue, unsigned transp, struct fb_info *info)
586{
587	u32 *pal = info->pseudo_palette;
588
589	if (regno > 15)
590		return -EINVAL;
591
592	pal[regno] = chan_to_field(red, &info->var.red)
593		| chan_to_field(green, &info->var.green)
594		| chan_to_field(blue, &info->var.blue)
595		| chan_to_field(transp, &info->var.transp);
596
597	return 0;
598}
599
600static int hvfb_blank(int blank, struct fb_info *info)
601{
602	return 1;	/* get fb_blank to set the colormap to all black */
603}
604
605static void hvfb_cfb_fillrect(struct fb_info *p,
606			      const struct fb_fillrect *rect)
607{
608	struct hvfb_par *par = p->par;
609
610	cfb_fillrect(p, rect);
611	if (par->synchronous_fb)
612		synthvid_update(p);
613}
614
615static void hvfb_cfb_copyarea(struct fb_info *p,
616			      const struct fb_copyarea *area)
617{
618	struct hvfb_par *par = p->par;
619
620	cfb_copyarea(p, area);
621	if (par->synchronous_fb)
622		synthvid_update(p);
623}
624
625static void hvfb_cfb_imageblit(struct fb_info *p,
626			       const struct fb_image *image)
627{
628	struct hvfb_par *par = p->par;
629
630	cfb_imageblit(p, image);
631	if (par->synchronous_fb)
632		synthvid_update(p);
633}
634
635static struct fb_ops hvfb_ops = {
636	.owner = THIS_MODULE,
637	.fb_check_var = hvfb_check_var,
638	.fb_set_par = hvfb_set_par,
639	.fb_setcolreg = hvfb_setcolreg,
640	.fb_fillrect = hvfb_cfb_fillrect,
641	.fb_copyarea = hvfb_cfb_copyarea,
642	.fb_imageblit = hvfb_cfb_imageblit,
643	.fb_blank = hvfb_blank,
644};
645
646
647/* Get options from kernel paramenter "video=" */
648static void hvfb_get_option(struct fb_info *info)
649{
650	struct hvfb_par *par = info->par;
651	char *opt = NULL, *p;
652	uint x = 0, y = 0;
653
654	if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
655		return;
656
657	p = strsep(&opt, "x");
658	if (!*p || kstrtouint(p, 0, &x) ||
659	    !opt || !*opt || kstrtouint(opt, 0, &y)) {
660		pr_err("Screen option is invalid: skipped\n");
661		return;
662	}
663
664	if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
665	    (par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
666	     x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8) ||
667	    (par->synthvid_version == SYNTHVID_VERSION_WIN7 &&
668	     (x > SYNTHVID_WIDTH_MAX_WIN7 || y > SYNTHVID_HEIGHT_MAX_WIN7))) {
669		pr_err("Screen resolution option is out of range: skipped\n");
670		return;
671	}
672
673	screen_width = x;
674	screen_height = y;
675	return;
676}
677
678
679/* Get framebuffer memory from Hyper-V video pci space */
680static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
681{
682	struct hvfb_par *par = info->par;
683	struct pci_dev *pdev  = NULL;
684	void __iomem *fb_virt;
685	int gen2vm = efi_enabled(EFI_BOOT);
686	resource_size_t pot_start, pot_end;
687	int ret;
688
689	if (gen2vm) {
690		pot_start = 0;
691		pot_end = -1;
692	} else {
693		pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
694			      PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
695		if (!pdev) {
696			pr_err("Unable to find PCI Hyper-V video\n");
697			return -ENODEV;
698		}
699
700		if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM) ||
701		    pci_resource_len(pdev, 0) < screen_fb_size)
702			goto err1;
703
704		pot_end = pci_resource_end(pdev, 0);
705		pot_start = pot_end - screen_fb_size + 1;
706	}
707
708	ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
709				  screen_fb_size, 0x100000, true);
710	if (ret != 0) {
711		pr_err("Unable to allocate framebuffer memory\n");
712		goto err1;
713	}
714
715	fb_virt = ioremap(par->mem->start, screen_fb_size);
716	if (!fb_virt)
717		goto err2;
718
719	info->apertures = alloc_apertures(1);
720	if (!info->apertures)
721		goto err3;
722
723	if (gen2vm) {
724		info->apertures->ranges[0].base = screen_info.lfb_base;
725		info->apertures->ranges[0].size = screen_info.lfb_size;
726		remove_conflicting_framebuffers(info->apertures,
727						KBUILD_MODNAME, false);
728	} else {
729		info->apertures->ranges[0].base = pci_resource_start(pdev, 0);
730		info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
731	}
732
733	info->fix.smem_start = par->mem->start;
734	info->fix.smem_len = screen_fb_size;
735	info->screen_base = fb_virt;
736	info->screen_size = screen_fb_size;
737
738	if (!gen2vm)
739		pci_dev_put(pdev);
740
741	return 0;
742
743err3:
744	iounmap(fb_virt);
745err2:
746	release_mem_region(par->mem->start, screen_fb_size);
747	par->mem = NULL;
748err1:
749	if (!gen2vm)
750		pci_dev_put(pdev);
751
752	return -ENOMEM;
753}
754
755/* Release the framebuffer */
756static void hvfb_putmem(struct fb_info *info)
757{
758	struct hvfb_par *par = info->par;
759
760	iounmap(info->screen_base);
761	release_mem_region(par->mem->start, screen_fb_size);
762	par->mem = NULL;
763}
764
765
766static int hvfb_probe(struct hv_device *hdev,
767		      const struct hv_vmbus_device_id *dev_id)
768{
769	struct fb_info *info;
770	struct hvfb_par *par;
771	int ret;
772
773	info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
774	if (!info) {
775		pr_err("No memory for framebuffer info\n");
776		return -ENOMEM;
777	}
778
779	par = info->par;
780	par->info = info;
781	par->fb_ready = false;
782	init_completion(&par->wait);
783	INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
784
785	/* Connect to VSP */
786	hv_set_drvdata(hdev, info);
787	ret = synthvid_connect_vsp(hdev);
788	if (ret) {
789		pr_err("Unable to connect to VSP\n");
790		goto error1;
791	}
792
793	ret = hvfb_getmem(hdev, info);
794	if (ret) {
795		pr_err("No memory for framebuffer\n");
796		goto error2;
797	}
798
799	hvfb_get_option(info);
800	pr_info("Screen resolution: %dx%d, Color depth: %d\n",
801		screen_width, screen_height, screen_depth);
802
803
804	/* Set up fb_info */
805	info->flags = FBINFO_DEFAULT;
806
807	info->var.xres_virtual = info->var.xres = screen_width;
808	info->var.yres_virtual = info->var.yres = screen_height;
809	info->var.bits_per_pixel = screen_depth;
810
811	if (info->var.bits_per_pixel == 16) {
812		info->var.red = (struct fb_bitfield){11, 5, 0};
813		info->var.green = (struct fb_bitfield){5, 6, 0};
814		info->var.blue = (struct fb_bitfield){0, 5, 0};
815		info->var.transp = (struct fb_bitfield){0, 0, 0};
816	} else {
817		info->var.red = (struct fb_bitfield){16, 8, 0};
818		info->var.green = (struct fb_bitfield){8, 8, 0};
819		info->var.blue = (struct fb_bitfield){0, 8, 0};
820		info->var.transp = (struct fb_bitfield){24, 8, 0};
821	}
822
823	info->var.activate = FB_ACTIVATE_NOW;
824	info->var.height = -1;
825	info->var.width = -1;
826	info->var.vmode = FB_VMODE_NONINTERLACED;
827
828	strcpy(info->fix.id, KBUILD_MODNAME);
829	info->fix.type = FB_TYPE_PACKED_PIXELS;
830	info->fix.visual = FB_VISUAL_TRUECOLOR;
831	info->fix.line_length = screen_width * screen_depth / 8;
832	info->fix.accel = FB_ACCEL_NONE;
833
834	info->fbops = &hvfb_ops;
835	info->pseudo_palette = par->pseudo_palette;
836
837	/* Send config to host */
838	ret = synthvid_send_config(hdev);
839	if (ret)
840		goto error;
841
842	ret = register_framebuffer(info);
843	if (ret) {
844		pr_err("Unable to register framebuffer\n");
845		goto error;
846	}
847
848	par->fb_ready = true;
849
850	par->synchronous_fb = false;
851	par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
852	atomic_notifier_chain_register(&panic_notifier_list,
853				       &par->hvfb_panic_nb);
854
855	return 0;
856
857error:
858	hvfb_putmem(info);
859error2:
860	vmbus_close(hdev->channel);
861error1:
862	cancel_delayed_work_sync(&par->dwork);
863	hv_set_drvdata(hdev, NULL);
864	framebuffer_release(info);
865	return ret;
866}
867
868
869static int hvfb_remove(struct hv_device *hdev)
870{
871	struct fb_info *info = hv_get_drvdata(hdev);
872	struct hvfb_par *par = info->par;
873
874	atomic_notifier_chain_unregister(&panic_notifier_list,
875					 &par->hvfb_panic_nb);
876
877	par->update = false;
878	par->fb_ready = false;
879
880	unregister_framebuffer(info);
881	cancel_delayed_work_sync(&par->dwork);
882
883	vmbus_close(hdev->channel);
884	hv_set_drvdata(hdev, NULL);
885
886	hvfb_putmem(info);
887	framebuffer_release(info);
888
889	return 0;
890}
891
892
893static const struct pci_device_id pci_stub_id_table[] = {
894	{
895		.vendor      = PCI_VENDOR_ID_MICROSOFT,
896		.device      = PCI_DEVICE_ID_HYPERV_VIDEO,
897	},
898	{ /* end of list */ }
899};
900
901static const struct hv_vmbus_device_id id_table[] = {
902	/* Synthetic Video Device GUID */
903	{HV_SYNTHVID_GUID},
904	{}
905};
906
907MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
908MODULE_DEVICE_TABLE(vmbus, id_table);
909
910static struct hv_driver hvfb_drv = {
911	.name = KBUILD_MODNAME,
912	.id_table = id_table,
913	.probe = hvfb_probe,
914	.remove = hvfb_remove,
915};
916
917static int hvfb_pci_stub_probe(struct pci_dev *pdev,
918			       const struct pci_device_id *ent)
919{
920	return 0;
921}
922
923static void hvfb_pci_stub_remove(struct pci_dev *pdev)
924{
925}
926
927static struct pci_driver hvfb_pci_stub_driver = {
928	.name =		KBUILD_MODNAME,
929	.id_table =	pci_stub_id_table,
930	.probe =	hvfb_pci_stub_probe,
931	.remove =	hvfb_pci_stub_remove,
932};
933
934static int __init hvfb_drv_init(void)
935{
936	int ret;
937
938	ret = vmbus_driver_register(&hvfb_drv);
939	if (ret != 0)
940		return ret;
941
942	ret = pci_register_driver(&hvfb_pci_stub_driver);
943	if (ret != 0) {
944		vmbus_driver_unregister(&hvfb_drv);
945		return ret;
946	}
947
948	return 0;
949}
950
951static void __exit hvfb_drv_exit(void)
952{
953	pci_unregister_driver(&hvfb_pci_stub_driver);
954	vmbus_driver_unregister(&hvfb_drv);
955}
956
957module_init(hvfb_drv_init);
958module_exit(hvfb_drv_exit);
959
960MODULE_LICENSE("GPL");
961MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");
962