// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2012, Microsoft Corporation.
*
* Author:
* Haiyang Zhang <[email protected]>
*/
/*
* Hyper-V Synthetic Video Frame Buffer Driver
*
* This is the driver for the Hyper-V Synthetic Video, which supports
* screen resolution up to Full HD 1920x1080 with 32 bit color on Windows
* Server 2012, and 1600x1200 with 16 bit color on Windows Server 2008 R2
* or earlier.
*
* It also solves the double mouse cursor issue of the emulated video mode.
*
* The default screen resolution is 1152x864, which may be changed by a
* kernel parameter:
* video=hyperv_fb:<width>x<height>
* For example: video=hyperv_fb:1280x1024
*
* Portrait orientation is also supported:
* For example: video=hyperv_fb:864x1152
*
* When a Windows 10 RS5+ host is used, the virtual machine screen
* resolution is obtained from the host. The "video=hyperv_fb" option is
* not needed, but still can be used to overwrite what the host specifies.
* The VM resolution on the host could be set by executing the powershell
* "set-vmvideo" command. For example
* set-vmvideo -vmname name -horizontalresolution:1920 \
* -verticalresolution:1200 -resolutiontype single
*
* Gen 1 VMs also support direct using VM's physical memory for framebuffer.
* It could improve the efficiency and performance for framebuffer and VM.
* This requires to allocate contiguous physical memory from Linux kernel's
* CMA memory allocator. To enable this, supply a kernel parameter to give
* enough memory space to CMA allocator for framebuffer. For example:
* cma=130m
* This gives 130MB memory to CMA allocator that can be allocated to
* framebuffer. For reference, 8K resolution (7680x4320) takes about
* 127MB memory.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/aperture.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/completion.h>
#include <linux/fb.h>
#include <linux/pci.h>
#include <linux/panic_notifier.h>
#include <linux/efi.h>
#include <linux/console.h>
#include <linux/hyperv.h>
/* Hyper-V Synthetic Video Protocol definitions and structures */
#define MAX_VMBUS_PKT_SIZE 0x4000
#define SYNTHVID_VERSION(major, minor) ((minor) << 16 | (major))
/* Support for VERSION_WIN7 is removed. #define is retained for reference. */
#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_VER_GET_MAJOR(ver) (ver & 0x0000ffff)
#define SYNTHVID_VER_GET_MINOR(ver) ((ver & 0xffff0000) >> 16)
#define SYNTHVID_DEPTH_WIN8 32
#define SYNTHVID_FB_SIZE_WIN8 (8 * 1024 * 1024)
enum pipe_msg_type {
PIPE_MSG_INVALID,
PIPE_MSG_DATA,
PIPE_MSG_MAX
};
struct pipe_msg_hdr {
u32 type;
u32 size; /* size of message after this field */
} __packed;
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
};
#define SYNTHVID_EDID_BLOCK_SIZE 128
#define SYNTHVID_MAX_RESOLUTION_COUNT 64
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_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_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 CURSOR_MAX_X 96
#define CURSOR_MAX_Y 96
#define CURSOR_ARGB_PIXEL_SIZE 4
#define CURSOR_MAX_SIZE (CURSOR_MAX_X * CURSOR_MAX_Y * CURSOR_ARGB_PIXEL_SIZE)
#define CURSOR_COMPLETE (-1)
struct synthvid_pointer_shape {
u8 part_idx;
u8 is_argb;
u32 width; /* CURSOR_MAX_X at most */
u32 height; /* 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;
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;
/* FB driver definitions and structures */
#define HVFB_WIDTH 1152 /* default screen width */
#define HVFB_HEIGHT 864 /* default screen height */
#define HVFB_WIDTH_MIN 640
#define HVFB_HEIGHT_MIN 480
#define RING_BUFSIZE (256 * 1024)
#define VSP_TIMEOUT (10 * HZ)
#define HVFB_UPDATE_DELAY (HZ / 20)
#define HVFB_ONDEMAND_THROTTLE (HZ / 20)
struct hvfb_par {
struct fb_info *info;
struct resource *mem;
bool fb_ready; /* fb device is ready */
struct completion wait;
u32 synthvid_version;
struct delayed_work dwork;
bool update;
bool update_saved; /* The value of 'update' before hibernation */
u32 pseudo_palette[16];
u8 init_buf[MAX_VMBUS_PKT_SIZE];
u8 recv_buf[MAX_VMBUS_PKT_SIZE];
/* If true, the VSC notifies the VSP on every framebuffer change */
bool synchronous_fb;
/* If true, need to copy from deferred IO mem to framebuffer mem */
bool need_docopy;
struct notifier_block hvfb_panic_nb;
/* Memory for deferred IO and frame buffer itself */
unsigned char *dio_vp;
unsigned char *mmio_vp;
phys_addr_t mmio_pp;
/* Dirty rectangle, protected by delayed_refresh_lock */
int x1, y1, x2, y2;
bool delayed_refresh;
spinlock_t delayed_refresh_lock;
};
static uint screen_width = HVFB_WIDTH;
static uint screen_height = HVFB_HEIGHT;
static uint screen_depth;
static uint screen_fb_size;
static uint dio_fb_size; /* FB size for deferred IO */
/* Send message to Hyper-V host */
static inline int synthvid_send(struct hv_device *hdev,
struct synthvid_msg *msg)
{
static atomic64_t request_id = ATOMIC64_INIT(0);
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)
pr_err_ratelimited("Unable to send packet via vmbus; error %d\n", ret);
return ret;
}
/* Send screen resolution info to host */
static int synthvid_send_situ(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct synthvid_msg msg;
if (!info)
return -ENODEV;
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 = 1;
msg.situ.video_output[0].vram_offset = 0;
msg.situ.video_output[0].depth_bits = info->var.bits_per_pixel;
msg.situ.video_output[0].width_pixels = info->var.xres;
msg.situ.video_output[0].height_pixels = info->var.yres;
msg.situ.video_output[0].pitch_bytes = info->fix.line_length;
synthvid_send(hdev, &msg);
return 0;
}
/* Send mouse pointer info to host */
static int synthvid_send_ptr(struct hv_device *hdev)
{
struct synthvid_msg msg;
memset(&msg, 0, sizeof(struct synthvid_msg));
msg.vid_hdr.type = SYNTHVID_POINTER_POSITION;
msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
sizeof(struct synthvid_pointer_position);
msg.ptr_pos.is_visible = 1;
msg.ptr_pos.video_output = 0;
msg.ptr_pos.image_x = 0;
msg.ptr_pos.image_y = 0;
synthvid_send(hdev, &msg);
memset(&msg, 0, sizeof(struct synthvid_msg));
msg.vid_hdr.type = SYNTHVID_POINTER_SHAPE;
msg.vid_hdr.size = sizeof(struct synthvid_msg_hdr) +
sizeof(struct synthvid_pointer_shape);
msg.ptr_shape.part_idx = CURSOR_COMPLETE;
msg.ptr_shape.is_argb = 1;
msg.ptr_shape.width = 1;
msg.ptr_shape.height = 1;
msg.ptr_shape.hot_x = 0;
msg.ptr_shape.hot_y = 0;
msg.ptr_shape.data[0] = 0;
msg.ptr_shape.data[1] = 1;
msg.ptr_shape.data[2] = 1;
msg.ptr_shape.data[3] = 1;
synthvid_send(hdev, &msg);
return 0;
}
/* Send updated screen area (dirty rectangle) location to host */
static int
synthvid_update(struct fb_info *info, int x1, int y1, int x2, int y2)
{
struct hv_device *hdev = device_to_hv_device(info->device);
struct synthvid_msg msg;
memset(&msg, 0, sizeof(struct synthvid_msg));
if (x2 == INT_MAX)
x2 = info->var.xres;
if (y2 == INT_MAX)
y2 = info->var.yres;
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 = (x1 > x2) ? 0 : x1;
msg.dirt.rect[0].y1 = (y1 > y2) ? 0 : y1;
msg.dirt.rect[0].x2 =
(x2 < x1 || x2 > info->var.xres) ? info->var.xres : x2;
msg.dirt.rect[0].y2 =
(y2 < y1 || y2 > info->var.yres) ? info->var.yres : y2;
synthvid_send(hdev, &msg);
return 0;
}
static void hvfb_docopy(struct hvfb_par *par,
unsigned long offset,
unsigned long size)
{
if (!par || !par->mmio_vp || !par->dio_vp || !par->fb_ready ||
size == 0 || offset >= dio_fb_size)
return;
if (offset + size > dio_fb_size)
size = dio_fb_size - offset;
memcpy(par->mmio_vp + offset, par->dio_vp + offset, size);
}
/* Deferred IO callback */
static void synthvid_deferred_io(struct fb_info *p, struct list_head *pagereflist)
{
struct hvfb_par *par = p->par;
struct fb_deferred_io_pageref *pageref;
unsigned long start, end;
int y1, y2, miny, maxy;
miny = INT_MAX;
maxy = 0;
/*
* Merge dirty pages. It is possible that last page cross
* over the end of frame buffer row yres. This is taken care of
* in synthvid_update function by clamping the y2
* value to yres.
*/
list_for_each_entry(pageref, pagereflist, list) {
start = pageref->offset;
end = start + PAGE_SIZE - 1;
y1 = start / p->fix.line_length;
y2 = end / p->fix.line_length;
miny = min_t(int, miny, y1);
maxy = max_t(int, maxy, y2);
/* Copy from dio space to mmio address */
if (par->fb_ready && par->need_docopy)
hvfb_docopy(par, start, PAGE_SIZE);
}
if (par->fb_ready && par->update)
synthvid_update(p, 0, miny, p->var.xres, maxy + 1);
}
static struct fb_deferred_io synthvid_defio = {
.delay = HZ / 20,
.deferred_io = synthvid_deferred_io,
};
/*
* Actions on received messages from host:
* Complete the wait event.
* Or, reply with screen and cursor info.
*/
static void synthvid_recv_sub(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par;
struct synthvid_msg *msg;
if (!info)
return;
par = info->par;
msg = (struct synthvid_msg *)par->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(par->init_buf, msg, MAX_VMBUS_PKT_SIZE);
complete(&par->wait);
return;
}
/* Reply with screen and cursor info */
if (msg->vid_hdr.type == SYNTHVID_FEATURE_CHANGE) {
if (par->fb_ready) {
synthvid_send_ptr(hdev);
synthvid_send_situ(hdev);
}
par->update = msg->feature_chg.is_dirt_needed;
if (par->update)
schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
}
}
/* Receive callback for messages from the host */
static void synthvid_receive(void *ctx)
{
struct hv_device *hdev = ctx;
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par;
struct synthvid_msg *recv_buf;
u32 bytes_recvd;
u64 req_id;
int ret;
if (!info)
return;
par = info->par;
recv_buf = (struct synthvid_msg *)par->recv_buf;
do {
ret = vmbus_recvpacket(hdev->channel, recv_buf,
MAX_VMBUS_PKT_SIZE,
&bytes_recvd, &req_id);
if (bytes_recvd > 0 &&
recv_buf->pipe_hdr.type == PIPE_MSG_DATA)
synthvid_recv_sub(hdev);
} while (bytes_recvd > 0 && ret == 0);
}
/* Check if the ver1 version is equal or greater than ver2 */
static inline bool synthvid_ver_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;
}
/* Check synthetic video protocol version with the host */
static int synthvid_negotiate_ver(struct hv_device *hdev, u32 ver)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par = info->par;
struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
int ret = 0;
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;
synthvid_send(hdev, msg);
t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
if (!t) {
pr_err("Time out on waiting version response\n");
ret = -ETIMEDOUT;
goto out;
}
if (!msg->ver_resp.is_accepted) {
ret = -ENODEV;
goto out;
}
par->synthvid_version = ver;
pr_info("Synthvid Version major %d, minor %d\n",
SYNTHVID_VER_GET_MAJOR(ver), SYNTHVID_VER_GET_MINOR(ver));
out:
return ret;
}
/* Get current resolution from the host */
static int synthvid_get_supported_resolution(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par = info->par;
struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
int ret = 0;
unsigned long t;
u8 index;
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;
synthvid_send(hdev, msg);
t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
if (!t) {
pr_err("Time out on waiting resolution response\n");
ret = -ETIMEDOUT;
goto out;
}
if (msg->resolution_resp.resolution_count == 0) {
pr_err("No supported resolutions\n");
ret = -ENODEV;
goto out;
}
index = msg->resolution_resp.default_resolution_index;
if (index >= msg->resolution_resp.resolution_count) {
pr_err("Invalid resolution index: %d\n", index);
ret = -ENODEV;
goto out;
}
screen_width =
msg->resolution_resp.supported_resolution[index].width;
screen_height =
msg->resolution_resp.supported_resolution[index].height;
out:
return ret;
}
/* Connect to VSP (Virtual Service Provider) on host */
static int synthvid_connect_vsp(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par = info->par;
int ret;
ret = vmbus_open(hdev->channel, RING_BUFSIZE, RING_BUFSIZE,
NULL, 0, synthvid_receive, hdev);
if (ret) {
pr_err("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 = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
if (!ret)
break;
fallthrough;
case VERSION_WIN8:
case VERSION_WIN8_1:
ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN8);
break;
default:
ret = synthvid_negotiate_ver(hdev, SYNTHVID_VERSION_WIN10);
break;
}
if (ret) {
pr_err("Synthetic video device version not accepted\n");
goto error;
}
screen_depth = SYNTHVID_DEPTH_WIN8;
if (synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10)) {
ret = synthvid_get_supported_resolution(hdev);
if (ret)
pr_info("Failed to get supported resolution from host, use default\n");
}
screen_fb_size = hdev->channel->offermsg.offer.
mmio_megabytes * 1024 * 1024;
return 0;
error:
vmbus_close(hdev->channel);
return ret;
}
/* Send VRAM and Situation messages to the host */
static int synthvid_send_config(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par = info->par;
struct synthvid_msg *msg = (struct synthvid_msg *)par->init_buf;
int ret = 0;
unsigned long t;
/* Send VRAM location */
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 = msg->vram.vram_gpa = par->mmio_pp;
msg->vram.is_vram_gpa_specified = 1;
synthvid_send(hdev, msg);
t = wait_for_completion_timeout(&par->wait, VSP_TIMEOUT);
if (!t) {
pr_err("Time out on waiting vram location ack\n");
ret = -ETIMEDOUT;
goto out;
}
if (msg->vram_ack.user_ctx != par->mmio_pp) {
pr_err("Unable to set VRAM location\n");
ret = -ENODEV;
goto out;
}
/* Send pointer and situation update */
synthvid_send_ptr(hdev);
synthvid_send_situ(hdev);
out:
return ret;
}
/*
* Delayed work callback:
* It is scheduled to call whenever update request is received and it has
* not been called in last HVFB_ONDEMAND_THROTTLE time interval.
*/
static void hvfb_update_work(struct work_struct *w)
{
struct hvfb_par *par = container_of(w, struct hvfb_par, dwork.work);
struct fb_info *info = par->info;
unsigned long flags;
int x1, x2, y1, y2;
int j;
spin_lock_irqsave(&par->delayed_refresh_lock, flags);
/* Reset the request flag */
par->delayed_refresh = false;
/* Store the dirty rectangle to local variables */
x1 = par->x1;
x2 = par->x2;
y1 = par->y1;
y2 = par->y2;
/* Clear dirty rectangle */
par->x1 = par->y1 = INT_MAX;
par->x2 = par->y2 = 0;
spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
if (x1 > info->var.xres || x2 > info->var.xres ||
y1 > info->var.yres || y2 > info->var.yres || x2 <= x1)
return;
/* Copy the dirty rectangle to frame buffer memory */
if (par->need_docopy)
for (j = y1; j < y2; j++)
hvfb_docopy(par,
j * info->fix.line_length +
(x1 * screen_depth / 8),
(x2 - x1) * screen_depth / 8);
/* Refresh */
if (par->fb_ready && par->update)
synthvid_update(info, x1, y1, x2, y2);
}
/*
* Control the on-demand refresh frequency. It schedules a delayed
* screen update if it has not yet.
*/
static void hvfb_ondemand_refresh_throttle(struct hvfb_par *par,
int x1, int y1, int w, int h)
{
unsigned long flags;
int x2 = x1 + w;
int y2 = y1 + h;
spin_lock_irqsave(&par->delayed_refresh_lock, flags);
/* Merge dirty rectangle */
par->x1 = min_t(int, par->x1, x1);
par->y1 = min_t(int, par->y1, y1);
par->x2 = max_t(int, par->x2, x2);
par->y2 = max_t(int, par->y2, y2);
/* Schedule a delayed screen update if not yet */
if (par->delayed_refresh == false) {
schedule_delayed_work(&par->dwork,
HVFB_ONDEMAND_THROTTLE);
par->delayed_refresh = true;
}
spin_unlock_irqrestore(&par->delayed_refresh_lock, flags);
}
static int hvfb_on_panic(struct notifier_block *nb,
unsigned long e, void *p)
{
struct hv_device *hdev;
struct hvfb_par *par;
struct fb_info *info;
par = container_of(nb, struct hvfb_par, hvfb_panic_nb);
info = par->info;
hdev = device_to_hv_device(info->device);
if (hv_ringbuffer_spinlock_busy(hdev->channel))
return NOTIFY_DONE;
par->synchronous_fb = true;
if (par->need_docopy)
hvfb_docopy(par, 0, dio_fb_size);
synthvid_update(info, 0, 0, INT_MAX, INT_MAX);
return NOTIFY_DONE;
}
/* Framebuffer operation handlers */
static int hvfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
if (var->xres < HVFB_WIDTH_MIN || var->yres < HVFB_HEIGHT_MIN ||
var->xres > screen_width || var->yres > screen_height ||
var->bits_per_pixel != screen_depth)
return -EINVAL;
var->xres_virtual = var->xres;
var->yres_virtual = var->yres;
return 0;
}
static int hvfb_set_par(struct fb_info *info)
{
struct hv_device *hdev = device_to_hv_device(info->device);
return synthvid_send_situ(hdev);
}
static inline u32 chan_to_field(u32 chan, struct fb_bitfield *bf)
{
return ((chan & 0xffff) >> (16 - bf->length)) << bf->offset;
}
static int hvfb_setcolreg(unsigned regno, unsigned red, unsigned green,
unsigned blue, unsigned transp, struct fb_info *info)
{
u32 *pal = info->pseudo_palette;
if (regno > 15)
return -EINVAL;
pal[regno] = chan_to_field(red, &info->var.red)
| chan_to_field(green, &info->var.green)
| chan_to_field(blue, &info->var.blue)
| chan_to_field(transp, &info->var.transp);
return 0;
}
static int hvfb_blank(int blank, struct fb_info *info)
{
return 1; /* get fb_blank to set the colormap to all black */
}
static void hvfb_ops_damage_range(struct fb_info *info, off_t off, size_t len)
{
/* TODO: implement damage handling */
}
static void hvfb_ops_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height)
{
struct hvfb_par *par = info->par;
if (par->synchronous_fb)
synthvid_update(info, 0, 0, INT_MAX, INT_MAX);
else
hvfb_ondemand_refresh_throttle(par, x, y, width, height);
}
/*
* TODO: GEN1 codepaths allocate from system or DMA-able memory. Fix the
* driver to use the _SYSMEM_ or _DMAMEM_ helpers in these cases.
*/
FB_GEN_DEFAULT_DEFERRED_IOMEM_OPS(hvfb_ops,
hvfb_ops_damage_range,
hvfb_ops_damage_area)
static const struct fb_ops hvfb_ops = {
.owner = THIS_MODULE,
FB_DEFAULT_DEFERRED_OPS(hvfb_ops),
.fb_check_var = hvfb_check_var,
.fb_set_par = hvfb_set_par,
.fb_setcolreg = hvfb_setcolreg,
.fb_blank = hvfb_blank,
};
/* Get options from kernel paramenter "video=" */
static void hvfb_get_option(struct fb_info *info)
{
struct hvfb_par *par = info->par;
char *opt = NULL, *p;
uint x = 0, y = 0;
if (fb_get_options(KBUILD_MODNAME, &opt) || !opt || !*opt)
return;
p = strsep(&opt, "x");
if (!*p || kstrtouint(p, 0, &x) ||
!opt || !*opt || kstrtouint(opt, 0, &y)) {
pr_err("Screen option is invalid: skipped\n");
return;
}
if (x < HVFB_WIDTH_MIN || y < HVFB_HEIGHT_MIN ||
(synthvid_ver_ge(par->synthvid_version, SYNTHVID_VERSION_WIN10) &&
(x * y * screen_depth / 8 > screen_fb_size)) ||
(par->synthvid_version == SYNTHVID_VERSION_WIN8 &&
x * y * screen_depth / 8 > SYNTHVID_FB_SIZE_WIN8)) {
pr_err("Screen resolution option is out of range: skipped\n");
return;
}
screen_width = x;
screen_height = y;
return;
}
/*
* Allocate enough contiguous physical memory.
* Return physical address if succeeded or -1 if failed.
*/
static phys_addr_t hvfb_get_phymem(struct hv_device *hdev,
unsigned int request_size)
{
struct page *page = NULL;
dma_addr_t dma_handle;
void *vmem;
phys_addr_t paddr = 0;
unsigned int order = get_order(request_size);
if (request_size == 0)
return -1;
if (order <= MAX_PAGE_ORDER) {
/* Call alloc_pages if the size is less than 2^MAX_PAGE_ORDER */
page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
if (!page)
return -1;
paddr = (page_to_pfn(page) << PAGE_SHIFT);
} else {
/* Allocate from CMA */
hdev->device.coherent_dma_mask = DMA_BIT_MASK(64);
vmem = dma_alloc_coherent(&hdev->device,
round_up(request_size, PAGE_SIZE),
&dma_handle,
GFP_KERNEL | __GFP_NOWARN);
if (!vmem)
return -1;
paddr = virt_to_phys(vmem);
}
return paddr;
}
/* Release contiguous physical memory */
static void hvfb_release_phymem(struct hv_device *hdev,
phys_addr_t paddr, unsigned int size)
{
unsigned int order = get_order(size);
if (order <= MAX_PAGE_ORDER)
__free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order);
else
dma_free_coherent(&hdev->device,
round_up(size, PAGE_SIZE),
phys_to_virt(paddr),
paddr);
}
/* Get framebuffer memory from Hyper-V video pci space */
static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
{
struct hvfb_par *par = info->par;
struct pci_dev *pdev = NULL;
void __iomem *fb_virt;
int gen2vm = efi_enabled(EFI_BOOT);
resource_size_t base = 0;
resource_size_t size = 0;
phys_addr_t paddr;
int ret;
if (!gen2vm) {
pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
if (!pdev) {
pr_err("Unable to find PCI Hyper-V video\n");
return -ENODEV;
}
base = pci_resource_start(pdev, 0);
size = pci_resource_len(pdev, 0);
/*
* For Gen 1 VM, we can directly use the contiguous memory
* from VM. If we succeed, deferred IO happens directly
* on this allocated framebuffer memory, avoiding extra
* memory copy.
*/
paddr = hvfb_get_phymem(hdev, screen_fb_size);
if (paddr != (phys_addr_t) -1) {
par->mmio_pp = paddr;
par->mmio_vp = par->dio_vp = __va(paddr);
info->fix.smem_start = paddr;
info->fix.smem_len = screen_fb_size;
info->screen_base = par->mmio_vp;
info->screen_size = screen_fb_size;
par->need_docopy = false;
goto getmem_done;
}
pr_info("Unable to allocate enough contiguous physical memory on Gen 1 VM. Using MMIO instead.\n");
}
/*
* Cannot use the contiguous physical memory.
* Allocate mmio space for framebuffer.
*/
dio_fb_size =
screen_width * screen_height * screen_depth / 8;
ret = vmbus_allocate_mmio(&par->mem, hdev, 0, -1,
screen_fb_size, 0x100000, true);
if (ret != 0) {
pr_err("Unable to allocate framebuffer memory\n");
goto err1;
}
/*
* Map the VRAM cacheable for performance. This is also required for
* VM Connect to display properly for ARM64 Linux VM, as the host also
* maps the VRAM cacheable.
*/
fb_virt = ioremap_cache(par->mem->start, screen_fb_size);
if (!fb_virt)
goto err2;
/* Allocate memory for deferred IO */
par->dio_vp = vzalloc(round_up(dio_fb_size, PAGE_SIZE));
if (par->dio_vp == NULL)
goto err3;
/* Physical address of FB device */
par->mmio_pp = par->mem->start;
/* Virtual address of FB device */
par->mmio_vp = (unsigned char *) fb_virt;
info->fix.smem_start = par->mem->start;
info->fix.smem_len = dio_fb_size;
info->screen_base = par->dio_vp;
info->screen_size = dio_fb_size;
getmem_done:
if (base && size)
aperture_remove_conflicting_devices(base, size, KBUILD_MODNAME);
else
aperture_remove_all_conflicting_devices(KBUILD_MODNAME);
if (!gen2vm)
pci_dev_put(pdev);
return 0;
err3:
iounmap(fb_virt);
err2:
vmbus_free_mmio(par->mem->start, screen_fb_size);
par->mem = NULL;
err1:
if (!gen2vm)
pci_dev_put(pdev);
return -ENOMEM;
}
/* Release the framebuffer */
static void hvfb_putmem(struct hv_device *hdev, struct fb_info *info)
{
struct hvfb_par *par = info->par;
if (par->need_docopy) {
vfree(par->dio_vp);
iounmap(info->screen_base);
vmbus_free_mmio(par->mem->start, screen_fb_size);
} else {
hvfb_release_phymem(hdev, info->fix.smem_start,
screen_fb_size);
}
par->mem = NULL;
}
static int hvfb_probe(struct hv_device *hdev,
const struct hv_vmbus_device_id *dev_id)
{
struct fb_info *info;
struct hvfb_par *par;
int ret;
info = framebuffer_alloc(sizeof(struct hvfb_par), &hdev->device);
if (!info)
return -ENOMEM;
par = info->par;
par->info = info;
par->fb_ready = false;
par->need_docopy = true;
init_completion(&par->wait);
INIT_DELAYED_WORK(&par->dwork, hvfb_update_work);
par->delayed_refresh = false;
spin_lock_init(&par->delayed_refresh_lock);
par->x1 = par->y1 = INT_MAX;
par->x2 = par->y2 = 0;
/* Connect to VSP */
hv_set_drvdata(hdev, info);
ret = synthvid_connect_vsp(hdev);
if (ret) {
pr_err("Unable to connect to VSP\n");
goto error1;
}
hvfb_get_option(info);
pr_info("Screen resolution: %dx%d, Color depth: %d, Frame buffer size: %d\n",
screen_width, screen_height, screen_depth, screen_fb_size);
ret = hvfb_getmem(hdev, info);
if (ret) {
pr_err("No memory for framebuffer\n");
goto error2;
}
/* Set up fb_info */
info->var.xres_virtual = info->var.xres = screen_width;
info->var.yres_virtual = info->var.yres = screen_height;
info->var.bits_per_pixel = screen_depth;
if (info->var.bits_per_pixel == 16) {
info->var.red = (struct fb_bitfield){11, 5, 0};
info->var.green = (struct fb_bitfield){5, 6, 0};
info->var.blue = (struct fb_bitfield){0, 5, 0};
info->var.transp = (struct fb_bitfield){0, 0, 0};
} else {
info->var.red = (struct fb_bitfield){16, 8, 0};
info->var.green = (struct fb_bitfield){8, 8, 0};
info->var.blue = (struct fb_bitfield){0, 8, 0};
info->var.transp = (struct fb_bitfield){24, 8, 0};
}
info->var.activate = FB_ACTIVATE_NOW;
info->var.height = -1;
info->var.width = -1;
info->var.vmode = FB_VMODE_NONINTERLACED;
strcpy(info->fix.id, KBUILD_MODNAME);
info->fix.type = FB_TYPE_PACKED_PIXELS;
info->fix.visual = FB_VISUAL_TRUECOLOR;
info->fix.line_length = screen_width * screen_depth / 8;
info->fix.accel = FB_ACCEL_NONE;
info->fbops = &hvfb_ops;
info->pseudo_palette = par->pseudo_palette;
/* Initialize deferred IO */
info->fbdefio = &synthvid_defio;
fb_deferred_io_init(info);
/* Send config to host */
ret = synthvid_send_config(hdev);
if (ret)
goto error;
ret = register_framebuffer(info);
if (ret) {
pr_err("Unable to register framebuffer\n");
goto error;
}
par->fb_ready = true;
par->synchronous_fb = false;
/*
* We need to be sure this panic notifier runs _before_ the
* vmbus disconnect, so order it by priority. It must execute
* before the function hv_panic_vmbus_unload() [drivers/hv/vmbus_drv.c],
* which is almost at the end of list, with priority = INT_MIN + 1.
*/
par->hvfb_panic_nb.notifier_call = hvfb_on_panic;
par->hvfb_panic_nb.priority = INT_MIN + 10;
atomic_notifier_chain_register(&panic_notifier_list,
&par->hvfb_panic_nb);
return 0;
error:
fb_deferred_io_cleanup(info);
hvfb_putmem(hdev, info);
error2:
vmbus_close(hdev->channel);
error1:
cancel_delayed_work_sync(&par->dwork);
hv_set_drvdata(hdev, NULL);
framebuffer_release(info);
return ret;
}
static void hvfb_remove(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par = info->par;
atomic_notifier_chain_unregister(&panic_notifier_list,
&par->hvfb_panic_nb);
par->update = false;
par->fb_ready = false;
fb_deferred_io_cleanup(info);
unregister_framebuffer(info);
cancel_delayed_work_sync(&par->dwork);
vmbus_close(hdev->channel);
hv_set_drvdata(hdev, NULL);
hvfb_putmem(hdev, info);
framebuffer_release(info);
}
static int hvfb_suspend(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par = info->par;
console_lock();
/* 1 means do suspend */
fb_set_suspend(info, 1);
cancel_delayed_work_sync(&par->dwork);
cancel_delayed_work_sync(&info->deferred_work);
par->update_saved = par->update;
par->update = false;
par->fb_ready = false;
vmbus_close(hdev->channel);
console_unlock();
return 0;
}
static int hvfb_resume(struct hv_device *hdev)
{
struct fb_info *info = hv_get_drvdata(hdev);
struct hvfb_par *par = info->par;
int ret;
console_lock();
ret = synthvid_connect_vsp(hdev);
if (ret != 0)
goto out;
ret = synthvid_send_config(hdev);
if (ret != 0) {
vmbus_close(hdev->channel);
goto out;
}
par->fb_ready = true;
par->update = par->update_saved;
schedule_delayed_work(&info->deferred_work, info->fbdefio->delay);
schedule_delayed_work(&par->dwork, HVFB_UPDATE_DELAY);
/* 0 means do resume */
fb_set_suspend(info, 0);
out:
console_unlock();
return ret;
}
static const struct pci_device_id pci_stub_id_table[] = {
{
.vendor = PCI_VENDOR_ID_MICROSOFT,
.device = PCI_DEVICE_ID_HYPERV_VIDEO,
},
{ /* end of list */ }
};
static const struct hv_vmbus_device_id id_table[] = {
/* Synthetic Video Device GUID */
{HV_SYNTHVID_GUID},
{}
};
MODULE_DEVICE_TABLE(pci, pci_stub_id_table);
MODULE_DEVICE_TABLE(vmbus, id_table);
static struct hv_driver hvfb_drv = {
.name = KBUILD_MODNAME,
.id_table = id_table,
.probe = hvfb_probe,
.remove = hvfb_remove,
.suspend = hvfb_suspend,
.resume = hvfb_resume,
.driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
static int hvfb_pci_stub_probe(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
return 0;
}
static void hvfb_pci_stub_remove(struct pci_dev *pdev)
{
}
static struct pci_driver hvfb_pci_stub_driver = {
.name = KBUILD_MODNAME,
.id_table = pci_stub_id_table,
.probe = hvfb_pci_stub_probe,
.remove = hvfb_pci_stub_remove,
.driver = {
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
}
};
static int __init hvfb_drv_init(void)
{
int ret;
if (fb_modesetting_disabled("hyper_fb"))
return -ENODEV;
ret = vmbus_driver_register(&hvfb_drv);
if (ret != 0)
return ret;
ret = pci_register_driver(&hvfb_pci_stub_driver);
if (ret != 0) {
vmbus_driver_unregister(&hvfb_drv);
return ret;
}
return 0;
}
static void __exit hvfb_drv_exit(void)
{
pci_unregister_driver(&hvfb_pci_stub_driver);
vmbus_driver_unregister(&hvfb_drv);
}
module_init(hvfb_drv_init);
module_exit(hvfb_drv_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Microsoft Hyper-V Synthetic Video Frame Buffer Driver");
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