drivers/gpu/drm/hyperv/hyperv_drm_proto.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright 2021 Microsoft
  *
  * Portions of this code is derived from hyperv_fb.c
  */

 #include <linux/hyperv.h>

 #include <drm/drm_print.h>
 #include <drm/drm_simple_kms_helper.h>

 #include "hyperv_drm.h"

 #define VMBUS_RING_BUFSIZE (256 * 1024)
 #define VMBUS_VSP_TIMEOUT (10 * HZ)

 #define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
 #define SYNTHVID_VER_GET_MAJOR(ver) (ver & 0x0000ffff)
 #define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16)
 #define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
 #define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
 #define SYNTHVID_VERSION_WIN10 SYNTHVID_VERSION(3, 5)

 #define SYNTHVID_DEPTH_WIN7 16
 #define SYNTHVID_DEPTH_WIN8 32
 #define SYNTHVID_FB_SIZE_WIN7 (4 * 1024 * 1024)
 #define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
 #define SYNTHVID_WIDTH_MAX_WIN7 1600
 #define SYNTHVID_HEIGHT_MAX_WIN7 1200

 enum pipe_msg_type {
 	PIPE_MSG_INVALID,
 	PIPE_MSG_DATA,
 	PIPE_MSG_MAX
 };

 enum synthvid_msg_type {
 	SYNTHVID_ERROR			= 0,
 	SYNTHVID_VERSION_REQUEST	= 1,
 	SYNTHVID_VERSION_RESPONSE	= 2,
 	SYNTHVID_VRAM_LOCATION		= 3,
 	SYNTHVID_VRAM_LOCATION_ACK	= 4,
 	SYNTHVID_SITUATION_UPDATE	= 5,
 	SYNTHVID_SITUATION_UPDATE_ACK	= 6,
 	SYNTHVID_POINTER_POSITION	= 7,
 	SYNTHVID_POINTER_SHAPE		= 8,
 	SYNTHVID_FEATURE_CHANGE		= 9,
 	SYNTHVID_DIRT			= 10,
 	SYNTHVID_RESOLUTION_REQUEST	= 13,
 	SYNTHVID_RESOLUTION_RESPONSE	= 14,

 	SYNTHVID_MAX			= 15
 };

 struct pipe_msg_hdr {
 	u32 type;
 	u32 size; /* size of message after this field */
 } __packed;

 struct hvd_screen_info {
 	u16 width;
 	u16 height;
 } __packed;

 struct synthvid_msg_hdr {
 	u32 type;
 	u32 size;  /* size of this header + payload after this field */
 } __packed;

 struct synthvid_version_req {
 	u32 version;
 } __packed;

 struct synthvid_version_resp {
 	u32 version;
 	u8 is_accepted;
 	u8 max_video_outputs;
 } __packed;

 struct synthvid_vram_location {
 	u64 user_ctx;
 	u8 is_vram_gpa_specified;
 	u64 vram_gpa;
 } __packed;

 struct synthvid_vram_location_ack {
 	u64 user_ctx;
 } __packed;

 struct video_output_situation {
 	u8 active;
 	u32 vram_offset;
 	u8 depth_bits;
 	u32 width_pixels;
 	u32 height_pixels;
 	u32 pitch_bytes;
 } __packed;

 struct synthvid_situation_update {
 	u64 user_ctx;
 	u8 video_output_count;
 	struct video_output_situation video_output[1];
 } __packed;

 struct synthvid_situation_update_ack {
 	u64 user_ctx;
 } __packed;

 struct synthvid_pointer_position {
 	u8 is_visible;
 	u8 video_output;
 	s32 image_x;
 	s32 image_y;
 } __packed;

 #define SYNTHVID_CURSOR_MAX_X 96
 #define SYNTHVID_CURSOR_MAX_Y 96
 #define SYNTHVID_CURSOR_ARGB_PIXEL_SIZE 4
 #define SYNTHVID_CURSOR_MAX_SIZE (SYNTHVID_CURSOR_MAX_X * \
 	SYNTHVID_CURSOR_MAX_Y * SYNTHVID_CURSOR_ARGB_PIXEL_SIZE)
 #define SYNTHVID_CURSOR_COMPLETE (-1)

 struct synthvid_pointer_shape {
 	u8 part_idx;
 	u8 is_argb;
 	u32 width; /* SYNTHVID_CURSOR_MAX_X at most */
 	u32 height; /* SYNTHVID_CURSOR_MAX_Y at most */
 	u32 hot_x; /* hotspot relative to upper-left of pointer image */
 	u32 hot_y;
 	u8 data[4];
 } __packed;

 struct synthvid_feature_change {
 	u8 is_dirt_needed;
 	u8 is_ptr_pos_needed;
 	u8 is_ptr_shape_needed;
 	u8 is_situ_needed;
 } __packed;

 struct rect {
 	s32 x1, y1; /* top left corner */
 	s32 x2, y2; /* bottom right corner, exclusive */
 } __packed;

 struct synthvid_dirt {
 	u8 video_output;
 	u8 dirt_count;
 	struct rect rect[1];
 } __packed;

 #define SYNTHVID_EDID_BLOCK_SIZE	128
 #define	SYNTHVID_MAX_RESOLUTION_COUNT	64

 struct synthvid_supported_resolution_req {
 	u8 maximum_resolution_count;
 } __packed;

 struct synthvid_supported_resolution_resp {
 	u8 edid_block[SYNTHVID_EDID_BLOCK_SIZE];
 	u8 resolution_count;
 	u8 default_resolution_index;
 	u8 is_standard;
 	struct hvd_screen_info supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT];
 } __packed;

 struct synthvid_msg {
 	struct pipe_msg_hdr pipe_hdr;
 	struct synthvid_msg_hdr vid_hdr;
 	union {
 		struct synthvid_version_req ver_req;
 		struct synthvid_version_resp ver_resp;
 		struct synthvid_vram_location vram;
 		struct synthvid_vram_location_ack vram_ack;
 		struct synthvid_situation_update situ;
 		struct synthvid_situation_update_ack situ_ack;
 		struct synthvid_pointer_position ptr_pos;
 		struct synthvid_pointer_shape ptr_shape;
 		struct synthvid_feature_change feature_chg;
 		struct synthvid_dirt dirt;
 		struct synthvid_supported_resolution_req resolution_req;
 		struct synthvid_supported_resolution_resp resolution_resp;
 	};
 } __packed;

 static inline bool hyperv_version_ge(u32 ver1, u32 ver2)
 {
 	if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) ||
 	    (SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) &&
 	     SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2)))
 		return true;

 	return false;
 }

 static inline int hyperv_sendpacket(struct hv_device *hdev, struct synthvid_msg *msg)
 {
 	static atomic64_t request_id = ATOMIC64_INIT(0);
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	int ret;

 	msg->pipe_hdr.type = PIPE_MSG_DATA;
 	msg->pipe_hdr.size = msg->vid_hdr.size;

 	ret = vmbus_sendpacket(hdev->channel, msg,
 			       msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
 			       atomic64_inc_return(&request_id),
 			       VM_PKT_DATA_INBAND, 0);

 	if (ret)
 		drm_err(&hv->dev, "Unable to send packet via vmbus\n");

 	return ret;
 }

 static int hyperv_negotiate_version(struct hv_device *hdev, u32 ver)
 {
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	struct synthvid_msg *msg = (struct synthvid_msg *)hv->init_buf;
 	struct drm_device *dev = &hv->dev;
 	unsigned long t;

 	memset(msg, 0, sizeof(struct synthvid_msg));
 	msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
 	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 		sizeof(struct synthvid_version_req);
 	msg->ver_req.version = ver;
 	hyperv_sendpacket(hdev, msg);

 	t = wait_for_completion_timeout(&hv->wait, VMBUS_VSP_TIMEOUT);
 	if (!t) {
 		drm_err(dev, "Time out on waiting version response\n");
 		return -ETIMEDOUT;
 	}

 	if (!msg->ver_resp.is_accepted) {
 		drm_err(dev, "Version request not accepted\n");
 		return -ENODEV;
 	}

 	hv->synthvid_version = ver;
 	drm_info(dev, "Synthvid Version major %d, minor %d\n",
 		 SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver));

 	return 0;
 }

 int hyperv_update_vram_location(struct hv_device *hdev, phys_addr_t vram_pp)
 {
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	struct synthvid_msg *msg = (struct synthvid_msg *)hv->init_buf;
 	struct drm_device *dev = &hv->dev;
 	unsigned long t;

 	memset(msg, 0, sizeof(struct synthvid_msg));
 	msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
 	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 		sizeof(struct synthvid_vram_location);
 	msg->vram.user_ctx = vram_pp;
 	msg->vram.vram_gpa = vram_pp;
 	msg->vram.is_vram_gpa_specified = 1;
 	hyperv_sendpacket(hdev, msg);

 	t = wait_for_completion_timeout(&hv->wait, VMBUS_VSP_TIMEOUT);
 	if (!t) {
 		drm_err(dev, "Time out on waiting vram location ack\n");
 		return -ETIMEDOUT;
 	}
 	if (msg->vram_ack.user_ctx != vram_pp) {
 		drm_err(dev, "Unable to set VRAM location\n");
 		return -ENODEV;
 	}

 	return 0;
 }

 int hyperv_update_situation(struct hv_device *hdev, u8 active, u32 bpp,
 			    u32 w, u32 h, u32 pitch)
 {
 	struct synthvid_msg msg;

 	memset(&msg, 0, sizeof(struct synthvid_msg));

 	msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
 	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 		sizeof(struct synthvid_situation_update);
 	msg.situ.user_ctx = 0;
 	msg.situ.video_output_count = 1;
 	msg.situ.video_output[0].active = active;
 	/* vram_offset should always be 0 */
 	msg.situ.video_output[0].vram_offset = 0;
 	msg.situ.video_output[0].depth_bits = bpp;
 	msg.situ.video_output[0].width_pixels = w;
 	msg.situ.video_output[0].height_pixels = h;
 	msg.situ.video_output[0].pitch_bytes = pitch;

 	hyperv_sendpacket(hdev, &msg);

 	return 0;
 }

 int hyperv_update_dirt(struct hv_device *hdev, struct drm_rect *rect)
 {
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	struct synthvid_msg msg;

 	if (!hv->dirt_needed)
 		return 0;

 	memset(&msg, 0, sizeof(struct synthvid_msg));

 	msg.vid_hdr.type = SYNTHVID_DIRT;
 	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 		sizeof(struct synthvid_dirt);
 	msg.dirt.video_output = 0;
 	msg.dirt.dirt_count = 1;
 	msg.dirt.rect[0].x1 = rect->x1;
 	msg.dirt.rect[0].y1 = rect->y1;
 	msg.dirt.rect[0].x2 = rect->x2;
 	msg.dirt.rect[0].y2 = rect->y2;

 	hyperv_sendpacket(hdev, &msg);

 	return 0;
 }

 static int hyperv_get_supported_resolution(struct hv_device *hdev)
 {
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	struct synthvid_msg *msg = (struct synthvid_msg *)hv->init_buf;
 	struct drm_device *dev = &hv->dev;
 	unsigned long t;
 	u8 index;
 	int i;

 	memset(msg, 0, sizeof(struct synthvid_msg));
 	msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST;
 	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
 		sizeof(struct synthvid_supported_resolution_req);
 	msg->resolution_req.maximum_resolution_count =
 		SYNTHVID_MAX_RESOLUTION_COUNT;
 	hyperv_sendpacket(hdev, msg);

 	t = wait_for_completion_timeout(&hv->wait, VMBUS_VSP_TIMEOUT);
 	if (!t) {
 		drm_err(dev, "Time out on waiting resolution response\n");
 		return -ETIMEDOUT;
 	}

 	if (msg->resolution_resp.resolution_count == 0) {
 		drm_err(dev, "No supported resolutions\n");
 		return -ENODEV;
 	}

 	index = msg->resolution_resp.default_resolution_index;
 	if (index >= msg->resolution_resp.resolution_count) {
 		drm_err(dev, "Invalid resolution index: %d\n", index);
 		return -ENODEV;
 	}

 	for (i = 0; i < msg->resolution_resp.resolution_count; i++) {
 		hv->screen_width_max = max_t(u32, hv->screen_width_max,
 			msg->resolution_resp.supported_resolution[i].width);
 		hv->screen_height_max = max_t(u32, hv->screen_height_max,
 			msg->resolution_resp.supported_resolution[i].height);
 	}

 	hv->preferred_width =
 		msg->resolution_resp.supported_resolution[index].width;
 	hv->preferred_height =
 		msg->resolution_resp.supported_resolution[index].height;

 	return 0;
 }

 static void hyperv_receive_sub(struct hv_device *hdev)
 {
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	struct synthvid_msg *msg;

 	if (!hv)
 		return;

 	msg = (struct synthvid_msg *)hv->recv_buf;

 	/* Complete the wait event */
 	if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE ||
 	    msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE ||
 	    msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
 		memcpy(hv->init_buf, msg, VMBUS_MAX_PACKET_SIZE);
 		complete(&hv->wait);
 		return;
 	}

 	if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE)
 		hv->dirt_needed = msg->feature_chg.is_dirt_needed;
 }

 static void hyperv_receive(void *ctx)
 {
 	struct hv_device *hdev = ctx;
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	struct synthvid_msg *recv_buf;
 	u32 bytes_recvd;
 	u64 req_id;
 	int ret;

 	if (!hv)
 		return;

 	recv_buf = (struct synthvid_msg *)hv->recv_buf;

 	do {
 		ret = vmbus_recvpacket(hdev->channel, recv_buf,
 				       VMBUS_MAX_PACKET_SIZE,
 				       &bytes_recvd, &req_id);
 		if (bytes_recvd > 0 &&
 		    recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
 			hyperv_receive_sub(hdev);
 	} while (bytes_recvd > 0 && ret == 0);
 }

 int hyperv_connect_vsp(struct hv_device *hdev)
 {
 	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
 	struct drm_device *dev = &hv->dev;
 	int ret;

 	ret = vmbus_open(hdev->channel, VMBUS_RING_BUFSIZE, VMBUS_RING_BUFSIZE,
 			 NULL, 0, hyperv_receive, hdev);
 	if (ret) {
 		drm_err(dev, "Unable to open vmbus channel\n");
 		return ret;
 	}

 	/* Negotiate the protocol version with host */
 	switch (vmbus_proto_version) {
 	case VERSION_WIN10:
 	case VERSION_WIN10_V5:
 		ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN10);
 		if (!ret)
 			break;
 		fallthrough;
 	case VERSION_WIN8:
 	case VERSION_WIN8_1:
 		ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN8);
 		if (!ret)
 			break;
 		fallthrough;
 	case VERSION_WS2008:
 	case VERSION_WIN7:
 		ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN7);
 		break;
 	default:
 		ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN10);
 		break;
 	}

 	if (ret) {
 		drm_err(dev, "Synthetic video device version not accepted %d\n", ret);
 		goto error;
 	}

 	if (hv->synthvid_version == SYNTHVID_VERSION_WIN7)
 		hv->screen_depth = SYNTHVID_DEPTH_WIN7;
 	else
 		hv->screen_depth = SYNTHVID_DEPTH_WIN8;

 	if (hyperv_version_ge(hv->synthvid_version, SYNTHVID_VERSION_WIN10)) {
 		ret = hyperv_get_supported_resolution(hdev);
 		if (ret)
 			drm_err(dev, "Failed to get supported resolution from host, use default\n");
 	} else {
 		hv->screen_width_max = SYNTHVID_WIDTH_MAX_WIN7;
 		hv->screen_height_max = SYNTHVID_HEIGHT_MAX_WIN7;
 	}

 	hv->mmio_megabytes = hdev->channel->offermsg.offer.mmio_megabytes;

 	return 0;

 error:
 	vmbus_close(hdev->channel);
 	return ret;
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Copyright 2021 Microsoft
	*
	* Portions of this code is derived from hyperv_fb.c
	*/

	#include <linux/hyperv.h>

	#include <drm/drm_print.h>
	#include <drm/drm_simple_kms_helper.h>

	#include "hyperv_drm.h"

	#define VMBUS_RING_BUFSIZE (256 * 1024)
	#define VMBUS_VSP_TIMEOUT (10 * HZ)

	#define SYNTHVID_VERSION(major, minor) ((minor) << 16 \| (major))
	#define SYNTHVID_VER_GET_MAJOR(ver) (ver & 0x0000ffff)
	#define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16)
	#define SYNTHVID_VERSION_WIN7 SYNTHVID_VERSION(3, 0)
	#define SYNTHVID_VERSION_WIN8 SYNTHVID_VERSION(3, 2)
	#define SYNTHVID_VERSION_WIN10 SYNTHVID_VERSION(3, 5)

	#define SYNTHVID_DEPTH_WIN7 16
	#define SYNTHVID_DEPTH_WIN8 32
	#define SYNTHVID_FB_SIZE_WIN7 (4 * 1024 * 1024)
	#define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
	#define SYNTHVID_WIDTH_MAX_WIN7 1600
	#define SYNTHVID_HEIGHT_MAX_WIN7 1200

	enum pipe_msg_type {
	PIPE_MSG_INVALID,
	PIPE_MSG_DATA,
	PIPE_MSG_MAX
	};

	enum synthvid_msg_type {
	SYNTHVID_ERROR = 0,
	SYNTHVID_VERSION_REQUEST = 1,
	SYNTHVID_VERSION_RESPONSE = 2,
	SYNTHVID_VRAM_LOCATION = 3,
	SYNTHVID_VRAM_LOCATION_ACK = 4,
	SYNTHVID_SITUATION_UPDATE = 5,
	SYNTHVID_SITUATION_UPDATE_ACK = 6,
	SYNTHVID_POINTER_POSITION = 7,
	SYNTHVID_POINTER_SHAPE = 8,
	SYNTHVID_FEATURE_CHANGE = 9,
	SYNTHVID_DIRT = 10,
	SYNTHVID_RESOLUTION_REQUEST = 13,
	SYNTHVID_RESOLUTION_RESPONSE = 14,

	SYNTHVID_MAX = 15
	};

	struct pipe_msg_hdr {
	u32 type;
	u32 size; /* size of message after this field */
	} __packed;

	struct hvd_screen_info {
	u16 width;
	u16 height;
	} __packed;

	struct synthvid_msg_hdr {
	u32 type;
	u32 size; /* size of this header + payload after this field */
	} __packed;

	struct synthvid_version_req {
	u32 version;
	} __packed;

	struct synthvid_version_resp {
	u32 version;
	u8 is_accepted;
	u8 max_video_outputs;
	} __packed;

	struct synthvid_vram_location {
	u64 user_ctx;
	u8 is_vram_gpa_specified;
	u64 vram_gpa;
	} __packed;

	struct synthvid_vram_location_ack {
	u64 user_ctx;
	} __packed;

	struct video_output_situation {
	u8 active;
	u32 vram_offset;
	u8 depth_bits;
	u32 width_pixels;
	u32 height_pixels;
	u32 pitch_bytes;
	} __packed;

	struct synthvid_situation_update {
	u64 user_ctx;
	u8 video_output_count;
	struct video_output_situation video_output[1];
	} __packed;

	struct synthvid_situation_update_ack {
	u64 user_ctx;
	} __packed;

	struct synthvid_pointer_position {
	u8 is_visible;
	u8 video_output;
	s32 image_x;
	s32 image_y;
	} __packed;

	#define SYNTHVID_CURSOR_MAX_X 96
	#define SYNTHVID_CURSOR_MAX_Y 96
	#define SYNTHVID_CURSOR_ARGB_PIXEL_SIZE 4
	#define SYNTHVID_CURSOR_MAX_SIZE (SYNTHVID_CURSOR_MAX_X * \
	SYNTHVID_CURSOR_MAX_Y * SYNTHVID_CURSOR_ARGB_PIXEL_SIZE)
	#define SYNTHVID_CURSOR_COMPLETE (-1)

	struct synthvid_pointer_shape {
	u8 part_idx;
	u8 is_argb;
	u32 width; /* SYNTHVID_CURSOR_MAX_X at most */
	u32 height; /* SYNTHVID_CURSOR_MAX_Y at most */
	u32 hot_x; /* hotspot relative to upper-left of pointer image */
	u32 hot_y;
	u8 data[4];
	} __packed;

	struct synthvid_feature_change {
	u8 is_dirt_needed;
	u8 is_ptr_pos_needed;
	u8 is_ptr_shape_needed;
	u8 is_situ_needed;
	} __packed;

	struct rect {
	s32 x1, y1; /* top left corner */
	s32 x2, y2; /* bottom right corner, exclusive */
	} __packed;

	struct synthvid_dirt {
	u8 video_output;
	u8 dirt_count;
	struct rect rect[1];
	} __packed;

	#define SYNTHVID_EDID_BLOCK_SIZE 128
	#define SYNTHVID_MAX_RESOLUTION_COUNT 64

	struct synthvid_supported_resolution_req {
	u8 maximum_resolution_count;
	} __packed;

	struct synthvid_supported_resolution_resp {
	u8 edid_block[SYNTHVID_EDID_BLOCK_SIZE];
	u8 resolution_count;
	u8 default_resolution_index;
	u8 is_standard;
	struct hvd_screen_info supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT];
	} __packed;

	struct synthvid_msg {
	struct pipe_msg_hdr pipe_hdr;
	struct synthvid_msg_hdr vid_hdr;
	union {
	struct synthvid_version_req ver_req;
	struct synthvid_version_resp ver_resp;
	struct synthvid_vram_location vram;
	struct synthvid_vram_location_ack vram_ack;
	struct synthvid_situation_update situ;
	struct synthvid_situation_update_ack situ_ack;
	struct synthvid_pointer_position ptr_pos;
	struct synthvid_pointer_shape ptr_shape;
	struct synthvid_feature_change feature_chg;
	struct synthvid_dirt dirt;
	struct synthvid_supported_resolution_req resolution_req;
	struct synthvid_supported_resolution_resp resolution_resp;
	};
	} __packed;

	static inline bool hyperv_version_ge(u32 ver1, u32 ver2)
	{
	if (SYNTHVID_VER_GET_MAJOR(ver1) > SYNTHVID_VER_GET_MAJOR(ver2) \|\|
	(SYNTHVID_VER_GET_MAJOR(ver1) == SYNTHVID_VER_GET_MAJOR(ver2) &&
	SYNTHVID_VER_GET_MINOR(ver1) >= SYNTHVID_VER_GET_MINOR(ver2)))
	return true;

	return false;
	}

	static inline int hyperv_sendpacket(struct hv_device hdev, struct synthvid_msg msg)
	{
	static atomic64_t request_id = ATOMIC64_INIT(0);
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	int ret;

	msg->pipe_hdr.type = PIPE_MSG_DATA;
	msg->pipe_hdr.size = msg->vid_hdr.size;

	ret = vmbus_sendpacket(hdev->channel, msg,
	msg->vid_hdr.size + sizeof(struct pipe_msg_hdr),
	atomic64_inc_return(&request_id),
	VM_PKT_DATA_INBAND, 0);

	if (ret)
	drm_err(&hv->dev, "Unable to send packet via vmbus\n");

	return ret;
	}

	static int hyperv_negotiate_version(struct hv_device *hdev, u32 ver)
	{
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	struct synthvid_msg msg = (struct synthvid_msg )hv->init_buf;
	struct drm_device *dev = &hv->dev;
	unsigned long t;

	memset(msg, 0, sizeof(struct synthvid_msg));
	msg->vid_hdr.type = SYNTHVID_VERSION_REQUEST;
	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
	sizeof(struct synthvid_version_req);
	msg->ver_req.version = ver;
	hyperv_sendpacket(hdev, msg);

	t = wait_for_completion_timeout(&hv->wait, VMBUS_VSP_TIMEOUT);
	if (!t) {
	drm_err(dev, "Time out on waiting version response\n");
	return -ETIMEDOUT;
	}

	if (!msg->ver_resp.is_accepted) {
	drm_err(dev, "Version request not accepted\n");
	return -ENODEV;
	}

	hv->synthvid_version = ver;
	drm_info(dev, "Synthvid Version major %d, minor %d\n",
	SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver));

	return 0;
	}

	int hyperv_update_vram_location(struct hv_device *hdev, phys_addr_t vram_pp)
	{
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	struct synthvid_msg msg = (struct synthvid_msg )hv->init_buf;
	struct drm_device *dev = &hv->dev;
	unsigned long t;

	memset(msg, 0, sizeof(struct synthvid_msg));
	msg->vid_hdr.type = SYNTHVID_VRAM_LOCATION;
	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
	sizeof(struct synthvid_vram_location);
	msg->vram.user_ctx = vram_pp;
	msg->vram.vram_gpa = vram_pp;
	msg->vram.is_vram_gpa_specified = 1;
	hyperv_sendpacket(hdev, msg);

	t = wait_for_completion_timeout(&hv->wait, VMBUS_VSP_TIMEOUT);
	if (!t) {
	drm_err(dev, "Time out on waiting vram location ack\n");
	return -ETIMEDOUT;
	}
	if (msg->vram_ack.user_ctx != vram_pp) {
	drm_err(dev, "Unable to set VRAM location\n");
	return -ENODEV;
	}

	return 0;
	}

	int hyperv_update_situation(struct hv_device *hdev, u8 active, u32 bpp,
	u32 w, u32 h, u32 pitch)
	{
	struct synthvid_msg msg;

	memset(&msg, 0, sizeof(struct synthvid_msg));

	msg.vid_hdr.type = SYNTHVID_SITUATION_UPDATE;
	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
	sizeof(struct synthvid_situation_update);
	msg.situ.user_ctx = 0;
	msg.situ.video_output_count = 1;
	msg.situ.video_output[0].active = active;
	/* vram_offset should always be 0 */
	msg.situ.video_output[0].vram_offset = 0;
	msg.situ.video_output[0].depth_bits = bpp;
	msg.situ.video_output[0].width_pixels = w;
	msg.situ.video_output[0].height_pixels = h;
	msg.situ.video_output[0].pitch_bytes = pitch;

	hyperv_sendpacket(hdev, &msg);

	return 0;
	}

	int hyperv_update_dirt(struct hv_device hdev, struct drm_rect rect)
	{
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	struct synthvid_msg msg;

	if (!hv->dirt_needed)
	return 0;

	memset(&msg, 0, sizeof(struct synthvid_msg));

	msg.vid_hdr.type = SYNTHVID_DIRT;
	msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
	sizeof(struct synthvid_dirt);
	msg.dirt.video_output = 0;
	msg.dirt.dirt_count = 1;
	msg.dirt.rect[0].x1 = rect->x1;
	msg.dirt.rect[0].y1 = rect->y1;
	msg.dirt.rect[0].x2 = rect->x2;
	msg.dirt.rect[0].y2 = rect->y2;

	hyperv_sendpacket(hdev, &msg);

	return 0;
	}

	static int hyperv_get_supported_resolution(struct hv_device *hdev)
	{
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	struct synthvid_msg msg = (struct synthvid_msg )hv->init_buf;
	struct drm_device *dev = &hv->dev;
	unsigned long t;
	u8 index;
	int i;

	memset(msg, 0, sizeof(struct synthvid_msg));
	msg->vid_hdr.type = SYNTHVID_RESOLUTION_REQUEST;
	msg->vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
	sizeof(struct synthvid_supported_resolution_req);
	msg->resolution_req.maximum_resolution_count =
	SYNTHVID_MAX_RESOLUTION_COUNT;
	hyperv_sendpacket(hdev, msg);

	t = wait_for_completion_timeout(&hv->wait, VMBUS_VSP_TIMEOUT);
	if (!t) {
	drm_err(dev, "Time out on waiting resolution response\n");
	return -ETIMEDOUT;
	}

	if (msg->resolution_resp.resolution_count == 0) {
	drm_err(dev, "No supported resolutions\n");
	return -ENODEV;
	}

	index = msg->resolution_resp.default_resolution_index;
	if (index >= msg->resolution_resp.resolution_count) {
	drm_err(dev, "Invalid resolution index: %d\n", index);
	return -ENODEV;
	}

	for (i = 0; i < msg->resolution_resp.resolution_count; i++) {
	hv->screen_width_max = max_t(u32, hv->screen_width_max,
	msg->resolution_resp.supported_resolution[i].width);
	hv->screen_height_max = max_t(u32, hv->screen_height_max,
	msg->resolution_resp.supported_resolution[i].height);
	}

	hv->preferred_width =
	msg->resolution_resp.supported_resolution[index].width;
	hv->preferred_height =
	msg->resolution_resp.supported_resolution[index].height;

	return 0;
	}

	static void hyperv_receive_sub(struct hv_device *hdev)
	{
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	struct synthvid_msg *msg;

	if (!hv)
	return;

	msg = (struct synthvid_msg *)hv->recv_buf;

	/* Complete the wait event */
	if (msg->vid_hdr.type == SYNTHVID_VERSION_RESPONSE \|\|
	msg->vid_hdr.type == SYNTHVID_RESOLUTION_RESPONSE \|\|
	msg->vid_hdr.type == SYNTHVID_VRAM_LOCATION_ACK) {
	memcpy(hv->init_buf, msg, VMBUS_MAX_PACKET_SIZE);
	complete(&hv->wait);
	return;
	}

	if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE)
	hv->dirt_needed = msg->feature_chg.is_dirt_needed;
	}

	static void hyperv_receive(void *ctx)
	{
	struct hv_device *hdev = ctx;
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	struct synthvid_msg *recv_buf;
	u32 bytes_recvd;
	u64 req_id;
	int ret;

	if (!hv)
	return;

	recv_buf = (struct synthvid_msg *)hv->recv_buf;

	do {
	ret = vmbus_recvpacket(hdev->channel, recv_buf,
	VMBUS_MAX_PACKET_SIZE,
	&bytes_recvd, &req_id);
	if (bytes_recvd > 0 &&
	recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
	hyperv_receive_sub(hdev);
	} while (bytes_recvd > 0 && ret == 0);
	}

	int hyperv_connect_vsp(struct hv_device *hdev)
	{
	struct hyperv_drm_device *hv = hv_get_drvdata(hdev);
	struct drm_device *dev = &hv->dev;
	int ret;

	ret = vmbus_open(hdev->channel, VMBUS_RING_BUFSIZE, VMBUS_RING_BUFSIZE,
	NULL, 0, hyperv_receive, hdev);
	if (ret) {
	drm_err(dev, "Unable to open vmbus channel\n");
	return ret;
	}

	/* Negotiate the protocol version with host */
	switch (vmbus_proto_version) {
	case VERSION_WIN10:
	case VERSION_WIN10_V5:
	ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN10);
	if (!ret)
	break;
	fallthrough;
	case VERSION_WIN8:
	case VERSION_WIN8_1:
	ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN8);
	if (!ret)
	break;
	fallthrough;
	case VERSION_WS2008:
	case VERSION_WIN7:
	ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN7);
	break;
	default:
	ret = hyperv_negotiate_version(hdev, SYNTHVID_VERSION_WIN10);
	break;
	}

	if (ret) {
	drm_err(dev, "Synthetic video device version not accepted %d\n", ret);
	goto error;
	}

	if (hv->synthvid_version == SYNTHVID_VERSION_WIN7)
	hv->screen_depth = SYNTHVID_DEPTH_WIN7;
	else
	hv->screen_depth = SYNTHVID_DEPTH_WIN8;

	if (hyperv_version_ge(hv->synthvid_version, SYNTHVID_VERSION_WIN10)) {
	ret = hyperv_get_supported_resolution(hdev);
	if (ret)
	drm_err(dev, "Failed to get supported resolution from host, use default\n");
	} else {
	hv->screen_width_max = SYNTHVID_WIDTH_MAX_WIN7;
	hv->screen_height_max = SYNTHVID_HEIGHT_MAX_WIN7;
	}

	hv->mmio_megabytes = hdev->channel->offermsg.offer.mmio_megabytes;

	return 0;

	error:
	vmbus_close(hdev->channel);
	return ret;
	}