// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2012, Microsoft Corporation. * * Author: * Haiyang Zhang */ /* * 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:x * 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 #include #include #include #include #include #include #include #include #include #include #include #include /* 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_cfb_fillrect(struct fb_info *p, const struct fb_fillrect *rect) { struct hvfb_par *par = p->par; cfb_fillrect(p, rect); if (par->synchronous_fb) synthvid_update(p, 0, 0, INT_MAX, INT_MAX); else hvfb_ondemand_refresh_throttle(par, rect->dx, rect->dy, rect->width, rect->height); } static void hvfb_cfb_copyarea(struct fb_info *p, const struct fb_copyarea *area) { struct hvfb_par *par = p->par; cfb_copyarea(p, area); if (par->synchronous_fb) synthvid_update(p, 0, 0, INT_MAX, INT_MAX); else hvfb_ondemand_refresh_throttle(par, area->dx, area->dy, area->width, area->height); } static void hvfb_cfb_imageblit(struct fb_info *p, const struct fb_image *image) { struct hvfb_par *par = p->par; cfb_imageblit(p, image); if (par->synchronous_fb) synthvid_update(p, 0, 0, INT_MAX, INT_MAX); else hvfb_ondemand_refresh_throttle(par, image->dx, image->dy, image->width, image->height); } static const struct fb_ops hvfb_ops = { .owner = THIS_MODULE, .fb_check_var = hvfb_check_var, .fb_set_par = hvfb_set_par, .fb_setcolreg = hvfb_setcolreg, .fb_fillrect = hvfb_cfb_fillrect, .fb_copyarea = hvfb_cfb_copyarea, .fb_imageblit = hvfb_cfb_imageblit, .fb_blank = hvfb_blank, .fb_mmap = fb_deferred_io_mmap, }; /* 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_ORDER) { /* Call alloc_pages if the size is less than 2^MAX_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_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, size; 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"); } else { base = screen_info.lfb_base; size = screen_info.lfb_size; } /* * 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: aperture_remove_conflicting_devices(base, size, KBUILD_MODNAME); if (gen2vm) { /* framebuffer is reallocated, clear screen_info to avoid misuse from kexec */ screen_info.lfb_size = 0; screen_info.lfb_base = 0; screen_info.orig_video_isVGA = 0; } else { 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->flags = FBINFO_DEFAULT; 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");