drivers/gpu/drm/vmwgfx/vmwgfx_scrn.c - kernel/msm.git - Git at Google

 /**************************************************************************
  *
  * Copyright © 2011 VMware, Inc., Palo Alto, CA., USA
  * All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sub license, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * The above copyright notice and this permission notice (including the
  * next paragraph) shall be included in all copies or substantial portions
  * of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  **************************************************************************/

 #include "vmwgfx_kms.h"


 #define vmw_crtc_to_sou(x) \
 	container_of(x, struct vmw_screen_object_unit, base.crtc)
 #define vmw_encoder_to_sou(x) \
 	container_of(x, struct vmw_screen_object_unit, base.encoder)
 #define vmw_connector_to_sou(x) \
 	container_of(x, struct vmw_screen_object_unit, base.connector)

 struct vmw_screen_object_display {
 	unsigned num_implicit;

 	struct vmw_framebuffer *implicit_fb;
 };

 /**
  * Display unit using screen objects.
  */
 struct vmw_screen_object_unit {
 	struct vmw_display_unit base;

 	unsigned long buffer_size; /**< Size of allocated buffer */
 	struct vmw_dma_buffer *buffer; /**< Backing store buffer */

 	bool defined;
 	bool active_implicit;
 };

 static void vmw_sou_destroy(struct vmw_screen_object_unit *sou)
 {
 	vmw_display_unit_cleanup(&sou->base);
 	kfree(sou);
 }


 /*
  * Screen Object Display Unit CRTC functions
  */

 static void vmw_sou_crtc_destroy(struct drm_crtc *crtc)
 {
 	vmw_sou_destroy(vmw_crtc_to_sou(crtc));
 }

 static void vmw_sou_del_active(struct vmw_private *vmw_priv,
 			      struct vmw_screen_object_unit *sou)
 {
 	struct vmw_screen_object_display *ld = vmw_priv->sou_priv;

 	if (sou->active_implicit) {
 		if (--(ld->num_implicit) == 0)
 			ld->implicit_fb = NULL;
 		sou->active_implicit = false;
 	}
 }

 static void vmw_sou_add_active(struct vmw_private *vmw_priv,
 			      struct vmw_screen_object_unit *sou,
 			      struct vmw_framebuffer *vfb)
 {
 	struct vmw_screen_object_display *ld = vmw_priv->sou_priv;

 	BUG_ON(!ld->num_implicit && ld->implicit_fb);

 	if (!sou->active_implicit && sou->base.is_implicit) {
 		ld->implicit_fb = vfb;
 		sou->active_implicit = true;
 		ld->num_implicit++;
 	}
 }

 /**
  * Send the fifo command to create a screen.
  */
 static int vmw_sou_fifo_create(struct vmw_private *dev_priv,
 			       struct vmw_screen_object_unit *sou,
 			       uint32_t x, uint32_t y,
 			       struct drm_display_mode *mode)
 {
 	size_t fifo_size;

 	struct {
 		struct {
 			uint32_t cmdType;
 		} header;
 		SVGAScreenObject obj;
 	} *cmd;

 	BUG_ON(!sou->buffer);

 	fifo_size = sizeof(*cmd);
 	cmd = vmw_fifo_reserve(dev_priv, fifo_size);
 	/* The hardware has hung, nothing we can do about it here. */
 	if (unlikely(cmd == NULL)) {
 		DRM_ERROR("Fifo reserve failed.\n");
 		return -ENOMEM;
 	}

 	memset(cmd, 0, fifo_size);
 	cmd->header.cmdType = SVGA_CMD_DEFINE_SCREEN;
 	cmd->obj.structSize = sizeof(SVGAScreenObject);
 	cmd->obj.id = sou->base.unit;
 	cmd->obj.flags = SVGA_SCREEN_HAS_ROOT |
 		(sou->base.unit == 0 ? SVGA_SCREEN_IS_PRIMARY : 0);
 	cmd->obj.size.width = mode->hdisplay;
 	cmd->obj.size.height = mode->vdisplay;
 	if (sou->base.is_implicit) {
 		cmd->obj.root.x = x;
 		cmd->obj.root.y = y;
 	} else {
 		cmd->obj.root.x = sou->base.gui_x;
 		cmd->obj.root.y = sou->base.gui_y;
 	}

 	/* Ok to assume that buffer is pinned in vram */
 	vmw_bo_get_guest_ptr(&sou->buffer->base, &cmd->obj.backingStore.ptr);
 	cmd->obj.backingStore.pitch = mode->hdisplay * 4;

 	vmw_fifo_commit(dev_priv, fifo_size);

 	sou->defined = true;

 	return 0;
 }

 /**
  * Send the fifo command to destroy a screen.
  */
 static int vmw_sou_fifo_destroy(struct vmw_private *dev_priv,
 				struct vmw_screen_object_unit *sou)
 {
 	size_t fifo_size;
 	int ret;

 	struct {
 		struct {
 			uint32_t cmdType;
 		} header;
 		SVGAFifoCmdDestroyScreen body;
 	} *cmd;

 	/* no need to do anything */
 	if (unlikely(!sou->defined))
 		return 0;

 	fifo_size = sizeof(*cmd);
 	cmd = vmw_fifo_reserve(dev_priv, fifo_size);
 	/* the hardware has hung, nothing we can do about it here */
 	if (unlikely(cmd == NULL)) {
 		DRM_ERROR("Fifo reserve failed.\n");
 		return -ENOMEM;
 	}

 	memset(cmd, 0, fifo_size);
 	cmd->header.cmdType = SVGA_CMD_DESTROY_SCREEN;
 	cmd->body.screenId = sou->base.unit;

 	vmw_fifo_commit(dev_priv, fifo_size);

 	/* Force sync */
 	ret = vmw_fallback_wait(dev_priv, false, true, 0, false, 3*HZ);
 	if (unlikely(ret != 0))
 		DRM_ERROR("Failed to sync with HW");
 	else
 		sou->defined = false;

 	return ret;
 }

 /**
  * Free the backing store.
  */
 static void vmw_sou_backing_free(struct vmw_private *dev_priv,
 				 struct vmw_screen_object_unit *sou)
 {
 	struct ttm_buffer_object *bo;

 	if (unlikely(sou->buffer == NULL))
 		return;

 	bo = &sou->buffer->base;
 	ttm_bo_unref(&bo);
 	sou->buffer = NULL;
 	sou->buffer_size = 0;
 }

 /**
  * Allocate the backing store for the buffer.
  */
 static int vmw_sou_backing_alloc(struct vmw_private *dev_priv,
 				 struct vmw_screen_object_unit *sou,
 				 unsigned long size)
 {
 	int ret;

 	if (sou->buffer_size == size)
 		return 0;

 	if (sou->buffer)
 		vmw_sou_backing_free(dev_priv, sou);

 	sou->buffer = kzalloc(sizeof(*sou->buffer), GFP_KERNEL);
 	if (unlikely(sou->buffer == NULL))
 		return -ENOMEM;

 	/* After we have alloced the backing store might not be able to
 	 * resume the overlays, this is preferred to failing to alloc.
 	 */
 	vmw_overlay_pause_all(dev_priv);
 	ret = vmw_dmabuf_init(dev_priv, sou->buffer, size,
 			      &vmw_vram_ne_placement,
 			      false, &vmw_dmabuf_bo_free);
 	vmw_overlay_resume_all(dev_priv);

 	if (unlikely(ret != 0))
 		sou->buffer = NULL; /* vmw_dmabuf_init frees on error */
 	else
 		sou->buffer_size = size;

 	return ret;
 }

 static int vmw_sou_crtc_set_config(struct drm_mode_set *set)
 {
 	struct vmw_private *dev_priv;
 	struct vmw_screen_object_unit *sou;
 	struct drm_connector *connector;
 	struct drm_display_mode *mode;
 	struct drm_encoder *encoder;
 	struct vmw_framebuffer *vfb;
 	struct drm_framebuffer *fb;
 	struct drm_crtc *crtc;
 	int ret = 0;

 	if (!set)
 		return -EINVAL;

 	if (!set->crtc)
 		return -EINVAL;

 	/* get the sou */
 	crtc = set->crtc;
 	sou = vmw_crtc_to_sou(crtc);
 	vfb = set->fb ? vmw_framebuffer_to_vfb(set->fb) : NULL;
 	dev_priv = vmw_priv(crtc->dev);

 	if (set->num_connectors > 1) {
 		DRM_ERROR("to many connectors\n");
 		return -EINVAL;
 	}

 	if (set->num_connectors == 1 &&
 	    set->connectors[0] != &sou->base.connector) {
 		DRM_ERROR("connector doesn't match %p %p\n",
 			set->connectors[0], &sou->base.connector);
 		return -EINVAL;
 	}

 	/* sou only supports one fb active at the time */
 	if (sou->base.is_implicit &&
 	    dev_priv->sou_priv->implicit_fb && vfb &&
 	    !(dev_priv->sou_priv->num_implicit == 1 &&
 	      sou->active_implicit) &&
 	    dev_priv->sou_priv->implicit_fb != vfb) {
 		DRM_ERROR("Multiple framebuffers not supported\n");
 		return -EINVAL;
 	}

 	/* since they always map one to one these are safe */
 	connector = &sou->base.connector;
 	encoder = &sou->base.encoder;

 	/* should we turn the crtc off */
 	if (set->num_connectors == 0 || !set->mode || !set->fb) {
 		ret = vmw_sou_fifo_destroy(dev_priv, sou);
 		/* the hardware has hung don't do anything more */
 		if (unlikely(ret != 0))
 			return ret;

 		connector->encoder = NULL;
 		encoder->crtc = NULL;
 		crtc->fb = NULL;
 		crtc->x = 0;
 		crtc->y = 0;

 		vmw_sou_del_active(dev_priv, sou);

 		vmw_sou_backing_free(dev_priv, sou);

 		return 0;
 	}


 	/* we now know we want to set a mode */
 	mode = set->mode;
 	fb = set->fb;

 	if (set->x + mode->hdisplay > fb->width ||
 	    set->y + mode->vdisplay > fb->height) {
 		DRM_ERROR("set outside of framebuffer\n");
 		return -EINVAL;
 	}

 	vmw_fb_off(dev_priv);

 	if (mode->hdisplay != crtc->mode.hdisplay ||
 	    mode->vdisplay != crtc->mode.vdisplay) {
 		/* no need to check if depth is different, because backing
 		 * store depth is forced to 4 by the device.
 		 */

 		ret = vmw_sou_fifo_destroy(dev_priv, sou);
 		/* the hardware has hung don't do anything more */
 		if (unlikely(ret != 0))
 			return ret;

 		vmw_sou_backing_free(dev_priv, sou);
 	}

 	if (!sou->buffer) {
 		/* forced to depth 4 by the device */
 		size_t size = mode->hdisplay * mode->vdisplay * 4;
 		ret = vmw_sou_backing_alloc(dev_priv, sou, size);
 		if (unlikely(ret != 0))
 			return ret;
 	}

 	ret = vmw_sou_fifo_create(dev_priv, sou, set->x, set->y, mode);
 	if (unlikely(ret != 0)) {
 		/*
 		 * We are in a bit of a situation here, the hardware has
 		 * hung and we may or may not have a buffer hanging of
 		 * the screen object, best thing to do is not do anything
 		 * if we where defined, if not just turn the crtc of.
 		 * Not what userspace wants but it needs to htfu.
 		 */
 		if (sou->defined)
 			return ret;

 		connector->encoder = NULL;
 		encoder->crtc = NULL;
 		crtc->fb = NULL;
 		crtc->x = 0;
 		crtc->y = 0;

 		return ret;
 	}

 	vmw_sou_add_active(dev_priv, sou, vfb);

 	connector->encoder = encoder;
 	encoder->crtc = crtc;
 	crtc->mode = *mode;
 	crtc->fb = fb;
 	crtc->x = set->x;
 	crtc->y = set->y;

 	return 0;
 }

 static struct drm_crtc_funcs vmw_screen_object_crtc_funcs = {
 	.save = vmw_du_crtc_save,
 	.restore = vmw_du_crtc_restore,
 	.cursor_set = vmw_du_crtc_cursor_set,
 	.cursor_move = vmw_du_crtc_cursor_move,
 	.gamma_set = vmw_du_crtc_gamma_set,
 	.destroy = vmw_sou_crtc_destroy,
 	.set_config = vmw_sou_crtc_set_config,
 	.page_flip = vmw_du_page_flip,
 };

 /*
  * Screen Object Display Unit encoder functions
  */

 static void vmw_sou_encoder_destroy(struct drm_encoder *encoder)
 {
 	vmw_sou_destroy(vmw_encoder_to_sou(encoder));
 }

 static struct drm_encoder_funcs vmw_screen_object_encoder_funcs = {
 	.destroy = vmw_sou_encoder_destroy,
 };

 /*
  * Screen Object Display Unit connector functions
  */

 static void vmw_sou_connector_destroy(struct drm_connector *connector)
 {
 	vmw_sou_destroy(vmw_connector_to_sou(connector));
 }

 static struct drm_connector_funcs vmw_legacy_connector_funcs = {
 	.dpms = vmw_du_connector_dpms,
 	.save = vmw_du_connector_save,
 	.restore = vmw_du_connector_restore,
 	.detect = vmw_du_connector_detect,
 	.fill_modes = vmw_du_connector_fill_modes,
 	.set_property = vmw_du_connector_set_property,
 	.destroy = vmw_sou_connector_destroy,
 };

 static int vmw_sou_init(struct vmw_private *dev_priv, unsigned unit)
 {
 	struct vmw_screen_object_unit *sou;
 	struct drm_device *dev = dev_priv->dev;
 	struct drm_connector *connector;
 	struct drm_encoder *encoder;
 	struct drm_crtc *crtc;

 	sou = kzalloc(sizeof(*sou), GFP_KERNEL);
 	if (!sou)
 		return -ENOMEM;

 	sou->base.unit = unit;
 	crtc = &sou->base.crtc;
 	encoder = &sou->base.encoder;
 	connector = &sou->base.connector;

 	sou->active_implicit = false;

 	sou->base.pref_active = (unit == 0);
 	sou->base.pref_width = dev_priv->initial_width;
 	sou->base.pref_height = dev_priv->initial_height;
 	sou->base.pref_mode = NULL;
 	sou->base.is_implicit = true;

 	drm_connector_init(dev, connector, &vmw_legacy_connector_funcs,
 			   DRM_MODE_CONNECTOR_VIRTUAL);
 	connector->status = vmw_du_connector_detect(connector, true);

 	drm_encoder_init(dev, encoder, &vmw_screen_object_encoder_funcs,
 			 DRM_MODE_ENCODER_VIRTUAL);
 	drm_mode_connector_attach_encoder(connector, encoder);
 	encoder->possible_crtcs = (1 << unit);
 	encoder->possible_clones = 0;

 	drm_crtc_init(dev, crtc, &vmw_screen_object_crtc_funcs);

 	drm_mode_crtc_set_gamma_size(crtc, 256);

 	drm_object_attach_property(&connector->base,
 				      dev->mode_config.dirty_info_property,
 				      1);

 	return 0;
 }

 int vmw_kms_init_screen_object_display(struct vmw_private *dev_priv)
 {
 	struct drm_device *dev = dev_priv->dev;
 	int i, ret;

 	if (dev_priv->sou_priv) {
 		DRM_INFO("sou system already on\n");
 		return -EINVAL;
 	}

 	if (!(dev_priv->capabilities & SVGA_CAP_SCREEN_OBJECT_2)) {
 		DRM_INFO("Not using screen objects,"
 			 " missing cap SCREEN_OBJECT_2\n");
 		return -ENOSYS;
 	}

 	ret = -ENOMEM;
 	dev_priv->sou_priv = kmalloc(sizeof(*dev_priv->sou_priv), GFP_KERNEL);
 	if (unlikely(!dev_priv->sou_priv))
 		goto err_no_mem;

 	dev_priv->sou_priv->num_implicit = 0;
 	dev_priv->sou_priv->implicit_fb = NULL;

 	ret = drm_vblank_init(dev, VMWGFX_NUM_DISPLAY_UNITS);
 	if (unlikely(ret != 0))
 		goto err_free;

 	ret = drm_mode_create_dirty_info_property(dev);
 	if (unlikely(ret != 0))
 		goto err_vblank_cleanup;

 	for (i = 0; i < VMWGFX_NUM_DISPLAY_UNITS; ++i)
 		vmw_sou_init(dev_priv, i);

 	DRM_INFO("Screen objects system initialized\n");

 	return 0;

 err_vblank_cleanup:
 	drm_vblank_cleanup(dev);
 err_free:
 	kfree(dev_priv->sou_priv);
 	dev_priv->sou_priv = NULL;
 err_no_mem:
 	return ret;
 }

 int vmw_kms_close_screen_object_display(struct vmw_private *dev_priv)
 {
 	struct drm_device *dev = dev_priv->dev;

 	if (!dev_priv->sou_priv)
 		return -ENOSYS;

 	drm_vblank_cleanup(dev);

 	kfree(dev_priv->sou_priv);

 	return 0;
 }

 /**
  * Returns if this unit can be page flipped.
  * Must be called with the mode_config mutex held.
  */
 bool vmw_kms_screen_object_flippable(struct vmw_private *dev_priv,
 				     struct drm_crtc *crtc)
 {
 	struct vmw_screen_object_unit *sou = vmw_crtc_to_sou(crtc);

 	if (!sou->base.is_implicit)
 		return true;

 	if (dev_priv->sou_priv->num_implicit != 1)
 		return false;

 	return true;
 }

 /**
  * Update the implicit fb to the current fb of this crtc.
  * Must be called with the mode_config mutex held.
  */
 void vmw_kms_screen_object_update_implicit_fb(struct vmw_private *dev_priv,
 					      struct drm_crtc *crtc)
 {
 	struct vmw_screen_object_unit *sou = vmw_crtc_to_sou(crtc);

 	BUG_ON(!sou->base.is_implicit);

 	dev_priv->sou_priv->implicit_fb =
 		vmw_framebuffer_to_vfb(sou->base.crtc.fb);
 }
	/**************************************************************************
	*
	* Copyright © 2011 VMware, Inc., Palo Alto, CA., USA
	* All Rights Reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the
	* "Software"), to deal in the Software without restriction, including
	* without limitation the rights to use, copy, modify, merge, publish,
	* distribute, sub license, and/or sell copies of the Software, and to
	* permit persons to whom the Software is furnished to do so, subject to
	* the following conditions:
	*
	* The above copyright notice and this permission notice (including the
	* next paragraph) shall be included in all copies or substantial portions
	* of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	**************************************************************************/

	#include "vmwgfx_kms.h"


	#define vmw_crtc_to_sou(x) \
	container_of(x, struct vmw_screen_object_unit, base.crtc)
	#define vmw_encoder_to_sou(x) \
	container_of(x, struct vmw_screen_object_unit, base.encoder)
	#define vmw_connector_to_sou(x) \
	container_of(x, struct vmw_screen_object_unit, base.connector)

	struct vmw_screen_object_display {
	unsigned num_implicit;

	struct vmw_framebuffer *implicit_fb;
	};

	/**
	* Display unit using screen objects.
	*/
	struct vmw_screen_object_unit {
	struct vmw_display_unit base;

	unsigned long buffer_size; /*< Size of allocated buffer /
	struct vmw_dma_buffer buffer; /< Backing store buffer /

	bool defined;
	bool active_implicit;
	};

	static void vmw_sou_destroy(struct vmw_screen_object_unit *sou)
	{
	vmw_display_unit_cleanup(&sou->base);
	kfree(sou);
	}


	/*
	* Screen Object Display Unit CRTC functions
	*/

	static void vmw_sou_crtc_destroy(struct drm_crtc *crtc)
	{
	vmw_sou_destroy(vmw_crtc_to_sou(crtc));
	}

	static void vmw_sou_del_active(struct vmw_private *vmw_priv,
	struct vmw_screen_object_unit *sou)
	{
	struct vmw_screen_object_display *ld = vmw_priv->sou_priv;

	if (sou->active_implicit) {
	if (--(ld->num_implicit) == 0)
	ld->implicit_fb = NULL;
	sou->active_implicit = false;
	}
	}

	static void vmw_sou_add_active(struct vmw_private *vmw_priv,
	struct vmw_screen_object_unit *sou,
	struct vmw_framebuffer *vfb)
	{
	struct vmw_screen_object_display *ld = vmw_priv->sou_priv;

	BUG_ON(!ld->num_implicit && ld->implicit_fb);

	if (!sou->active_implicit && sou->base.is_implicit) {
	ld->implicit_fb = vfb;
	sou->active_implicit = true;
	ld->num_implicit++;
	}
	}

	/**
	* Send the fifo command to create a screen.
	*/
	static int vmw_sou_fifo_create(struct vmw_private *dev_priv,
	struct vmw_screen_object_unit *sou,
	uint32_t x, uint32_t y,
	struct drm_display_mode *mode)
	{
	size_t fifo_size;

	struct {
	struct {
	uint32_t cmdType;
	} header;
	SVGAScreenObject obj;
	} *cmd;

	BUG_ON(!sou->buffer);

	fifo_size = sizeof(*cmd);
	cmd = vmw_fifo_reserve(dev_priv, fifo_size);
	/* The hardware has hung, nothing we can do about it here. */
	if (unlikely(cmd == NULL)) {
	DRM_ERROR("Fifo reserve failed.\n");
	return -ENOMEM;
	}

	memset(cmd, 0, fifo_size);
	cmd->header.cmdType = SVGA_CMD_DEFINE_SCREEN;
	cmd->obj.structSize = sizeof(SVGAScreenObject);
	cmd->obj.id = sou->base.unit;
	cmd->obj.flags = SVGA_SCREEN_HAS_ROOT \|
	(sou->base.unit == 0 ? SVGA_SCREEN_IS_PRIMARY : 0);
	cmd->obj.size.width = mode->hdisplay;
	cmd->obj.size.height = mode->vdisplay;
	if (sou->base.is_implicit) {
	cmd->obj.root.x = x;
	cmd->obj.root.y = y;
	} else {
	cmd->obj.root.x = sou->base.gui_x;
	cmd->obj.root.y = sou->base.gui_y;
	}

	/* Ok to assume that buffer is pinned in vram */
	vmw_bo_get_guest_ptr(&sou->buffer->base, &cmd->obj.backingStore.ptr);
	cmd->obj.backingStore.pitch = mode->hdisplay * 4;

	vmw_fifo_commit(dev_priv, fifo_size);

	sou->defined = true;

	return 0;
	}

	/**
	* Send the fifo command to destroy a screen.
	*/
	static int vmw_sou_fifo_destroy(struct vmw_private *dev_priv,
	struct vmw_screen_object_unit *sou)
	{
	size_t fifo_size;
	int ret;

	struct {
	struct {
	uint32_t cmdType;
	} header;
	SVGAFifoCmdDestroyScreen body;
	} *cmd;

	/* no need to do anything */
	if (unlikely(!sou->defined))
	return 0;

	fifo_size = sizeof(*cmd);
	cmd = vmw_fifo_reserve(dev_priv, fifo_size);
	/* the hardware has hung, nothing we can do about it here */
	if (unlikely(cmd == NULL)) {
	DRM_ERROR("Fifo reserve failed.\n");
	return -ENOMEM;
	}

	memset(cmd, 0, fifo_size);
	cmd->header.cmdType = SVGA_CMD_DESTROY_SCREEN;
	cmd->body.screenId = sou->base.unit;

	vmw_fifo_commit(dev_priv, fifo_size);

	/* Force sync */
	ret = vmw_fallback_wait(dev_priv, false, true, 0, false, 3*HZ);
	if (unlikely(ret != 0))
	DRM_ERROR("Failed to sync with HW");
	else
	sou->defined = false;

	return ret;
	}

	/**
	* Free the backing store.
	*/
	static void vmw_sou_backing_free(struct vmw_private *dev_priv,
	struct vmw_screen_object_unit *sou)
	{
	struct ttm_buffer_object *bo;

	if (unlikely(sou->buffer == NULL))
	return;

	bo = &sou->buffer->base;
	ttm_bo_unref(&bo);
	sou->buffer = NULL;
	sou->buffer_size = 0;
	}

	/**
	* Allocate the backing store for the buffer.
	*/
	static int vmw_sou_backing_alloc(struct vmw_private *dev_priv,
	struct vmw_screen_object_unit *sou,
	unsigned long size)
	{
	int ret;

	if (sou->buffer_size == size)
	return 0;

	if (sou->buffer)
	vmw_sou_backing_free(dev_priv, sou);

	sou->buffer = kzalloc(sizeof(*sou->buffer), GFP_KERNEL);
	if (unlikely(sou->buffer == NULL))
	return -ENOMEM;

	/* After we have alloced the backing store might not be able to
	* resume the overlays, this is preferred to failing to alloc.
	*/
	vmw_overlay_pause_all(dev_priv);
	ret = vmw_dmabuf_init(dev_priv, sou->buffer, size,
	&vmw_vram_ne_placement,
	false, &vmw_dmabuf_bo_free);
	vmw_overlay_resume_all(dev_priv);

	if (unlikely(ret != 0))
	sou->buffer = NULL; /* vmw_dmabuf_init frees on error */
	else
	sou->buffer_size = size;

	return ret;
	}

	static int vmw_sou_crtc_set_config(struct drm_mode_set *set)
	{
	struct vmw_private *dev_priv;
	struct vmw_screen_object_unit *sou;
	struct drm_connector *connector;
	struct drm_display_mode *mode;
	struct drm_encoder *encoder;
	struct vmw_framebuffer *vfb;
	struct drm_framebuffer *fb;
	struct drm_crtc *crtc;
	int ret = 0;

	if (!set)
	return -EINVAL;

	if (!set->crtc)
	return -EINVAL;

	/* get the sou */
	crtc = set->crtc;
	sou = vmw_crtc_to_sou(crtc);
	vfb = set->fb ? vmw_framebuffer_to_vfb(set->fb) : NULL;
	dev_priv = vmw_priv(crtc->dev);

	if (set->num_connectors > 1) {
	DRM_ERROR("to many connectors\n");
	return -EINVAL;
	}

	if (set->num_connectors == 1 &&
	set->connectors[0] != &sou->base.connector) {
	DRM_ERROR("connector doesn't match %p %p\n",
	set->connectors[0], &sou->base.connector);
	return -EINVAL;
	}

	/* sou only supports one fb active at the time */
	if (sou->base.is_implicit &&
	dev_priv->sou_priv->implicit_fb && vfb &&
	!(dev_priv->sou_priv->num_implicit == 1 &&
	sou->active_implicit) &&
	dev_priv->sou_priv->implicit_fb != vfb) {
	DRM_ERROR("Multiple framebuffers not supported\n");
	return -EINVAL;
	}

	/* since they always map one to one these are safe */
	connector = &sou->base.connector;
	encoder = &sou->base.encoder;

	/* should we turn the crtc off */
	if (set->num_connectors == 0 \|\| !set->mode \|\| !set->fb) {
	ret = vmw_sou_fifo_destroy(dev_priv, sou);
	/* the hardware has hung don't do anything more */
	if (unlikely(ret != 0))
	return ret;

	connector->encoder = NULL;
	encoder->crtc = NULL;
	crtc->fb = NULL;
	crtc->x = 0;
	crtc->y = 0;

	vmw_sou_del_active(dev_priv, sou);

	vmw_sou_backing_free(dev_priv, sou);

	return 0;
	}


	/* we now know we want to set a mode */
	mode = set->mode;
	fb = set->fb;

	if (set->x + mode->hdisplay > fb->width \|\|
	set->y + mode->vdisplay > fb->height) {
	DRM_ERROR("set outside of framebuffer\n");
	return -EINVAL;
	}

	vmw_fb_off(dev_priv);

	if (mode->hdisplay != crtc->mode.hdisplay \|\|
	mode->vdisplay != crtc->mode.vdisplay) {
	/* no need to check if depth is different, because backing
	* store depth is forced to 4 by the device.
	*/

	ret = vmw_sou_fifo_destroy(dev_priv, sou);
	/* the hardware has hung don't do anything more */
	if (unlikely(ret != 0))
	return ret;

	vmw_sou_backing_free(dev_priv, sou);
	}

	if (!sou->buffer) {
	/* forced to depth 4 by the device */
	size_t size = mode->hdisplay * mode->vdisplay * 4;
	ret = vmw_sou_backing_alloc(dev_priv, sou, size);
	if (unlikely(ret != 0))
	return ret;
	}

	ret = vmw_sou_fifo_create(dev_priv, sou, set->x, set->y, mode);
	if (unlikely(ret != 0)) {
	/*
	* We are in a bit of a situation here, the hardware has
	* hung and we may or may not have a buffer hanging of
	* the screen object, best thing to do is not do anything
	* if we where defined, if not just turn the crtc of.
	* Not what userspace wants but it needs to htfu.
	*/
	if (sou->defined)
	return ret;

	connector->encoder = NULL;
	encoder->crtc = NULL;
	crtc->fb = NULL;
	crtc->x = 0;
	crtc->y = 0;

	return ret;
	}

	vmw_sou_add_active(dev_priv, sou, vfb);

	connector->encoder = encoder;
	encoder->crtc = crtc;
	crtc->mode = *mode;
	crtc->fb = fb;
	crtc->x = set->x;
	crtc->y = set->y;

	return 0;
	}

	static struct drm_crtc_funcs vmw_screen_object_crtc_funcs = {
	.save = vmw_du_crtc_save,
	.restore = vmw_du_crtc_restore,
	.cursor_set = vmw_du_crtc_cursor_set,
	.cursor_move = vmw_du_crtc_cursor_move,
	.gamma_set = vmw_du_crtc_gamma_set,
	.destroy = vmw_sou_crtc_destroy,
	.set_config = vmw_sou_crtc_set_config,
	.page_flip = vmw_du_page_flip,
	};

	/*
	* Screen Object Display Unit encoder functions
	*/

	static void vmw_sou_encoder_destroy(struct drm_encoder *encoder)
	{
	vmw_sou_destroy(vmw_encoder_to_sou(encoder));
	}

	static struct drm_encoder_funcs vmw_screen_object_encoder_funcs = {
	.destroy = vmw_sou_encoder_destroy,
	};

	/*
	* Screen Object Display Unit connector functions
	*/

	static void vmw_sou_connector_destroy(struct drm_connector *connector)
	{
	vmw_sou_destroy(vmw_connector_to_sou(connector));
	}

	static struct drm_connector_funcs vmw_legacy_connector_funcs = {
	.dpms = vmw_du_connector_dpms,
	.save = vmw_du_connector_save,
	.restore = vmw_du_connector_restore,
	.detect = vmw_du_connector_detect,
	.fill_modes = vmw_du_connector_fill_modes,
	.set_property = vmw_du_connector_set_property,
	.destroy = vmw_sou_connector_destroy,
	};

	static int vmw_sou_init(struct vmw_private *dev_priv, unsigned unit)
	{
	struct vmw_screen_object_unit *sou;
	struct drm_device *dev = dev_priv->dev;
	struct drm_connector *connector;
	struct drm_encoder *encoder;
	struct drm_crtc *crtc;

	sou = kzalloc(sizeof(*sou), GFP_KERNEL);
	if (!sou)
	return -ENOMEM;

	sou->base.unit = unit;
	crtc = &sou->base.crtc;
	encoder = &sou->base.encoder;
	connector = &sou->base.connector;

	sou->active_implicit = false;

	sou->base.pref_active = (unit == 0);
	sou->base.pref_width = dev_priv->initial_width;
	sou->base.pref_height = dev_priv->initial_height;
	sou->base.pref_mode = NULL;
	sou->base.is_implicit = true;

	drm_connector_init(dev, connector, &vmw_legacy_connector_funcs,
	DRM_MODE_CONNECTOR_VIRTUAL);
	connector->status = vmw_du_connector_detect(connector, true);

	drm_encoder_init(dev, encoder, &vmw_screen_object_encoder_funcs,
	DRM_MODE_ENCODER_VIRTUAL);
	drm_mode_connector_attach_encoder(connector, encoder);
	encoder->possible_crtcs = (1 << unit);
	encoder->possible_clones = 0;

	drm_crtc_init(dev, crtc, &vmw_screen_object_crtc_funcs);

	drm_mode_crtc_set_gamma_size(crtc, 256);

	drm_object_attach_property(&connector->base,
	dev->mode_config.dirty_info_property,
	1);

	return 0;
	}

	int vmw_kms_init_screen_object_display(struct vmw_private *dev_priv)
	{
	struct drm_device *dev = dev_priv->dev;
	int i, ret;

	if (dev_priv->sou_priv) {
	DRM_INFO("sou system already on\n");
	return -EINVAL;
	}

	if (!(dev_priv->capabilities & SVGA_CAP_SCREEN_OBJECT_2)) {
	DRM_INFO("Not using screen objects,"
	" missing cap SCREEN_OBJECT_2\n");
	return -ENOSYS;
	}

	ret = -ENOMEM;
	dev_priv->sou_priv = kmalloc(sizeof(*dev_priv->sou_priv), GFP_KERNEL);
	if (unlikely(!dev_priv->sou_priv))
	goto err_no_mem;

	dev_priv->sou_priv->num_implicit = 0;
	dev_priv->sou_priv->implicit_fb = NULL;

	ret = drm_vblank_init(dev, VMWGFX_NUM_DISPLAY_UNITS);
	if (unlikely(ret != 0))
	goto err_free;

	ret = drm_mode_create_dirty_info_property(dev);
	if (unlikely(ret != 0))
	goto err_vblank_cleanup;

	for (i = 0; i < VMWGFX_NUM_DISPLAY_UNITS; ++i)
	vmw_sou_init(dev_priv, i);

	DRM_INFO("Screen objects system initialized\n");

	return 0;

	err_vblank_cleanup:
	drm_vblank_cleanup(dev);
	err_free:
	kfree(dev_priv->sou_priv);
	dev_priv->sou_priv = NULL;
	err_no_mem:
	return ret;
	}

	int vmw_kms_close_screen_object_display(struct vmw_private *dev_priv)
	{
	struct drm_device *dev = dev_priv->dev;

	if (!dev_priv->sou_priv)
	return -ENOSYS;

	drm_vblank_cleanup(dev);

	kfree(dev_priv->sou_priv);

	return 0;
	}

	/**
	* Returns if this unit can be page flipped.
	* Must be called with the mode_config mutex held.
	*/
	bool vmw_kms_screen_object_flippable(struct vmw_private *dev_priv,
	struct drm_crtc *crtc)
	{
	struct vmw_screen_object_unit *sou = vmw_crtc_to_sou(crtc);

	if (!sou->base.is_implicit)
	return true;

	if (dev_priv->sou_priv->num_implicit != 1)
	return false;

	return true;
	}

	/**
	* Update the implicit fb to the current fb of this crtc.
	* Must be called with the mode_config mutex held.
	*/
	void vmw_kms_screen_object_update_implicit_fb(struct vmw_private *dev_priv,
	struct drm_crtc *crtc)
	{
	struct vmw_screen_object_unit *sou = vmw_crtc_to_sou(crtc);

	BUG_ON(!sou->base.is_implicit);

	dev_priv->sou_priv->implicit_fb =
	vmw_framebuffer_to_vfb(sou->base.crtc.fb);
	}