path: root/src/videocore-exa.c

/* vim: set noet sw=8 sts=8 cino=:0,t0,(0 :
 *
 * Copyright © 2012 Collabora Ltd.
 *
 * 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, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is fur-
 * nished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice 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, FIT-
 * NESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 * XFREE86 PROJECT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CON-
 * NECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * 
 * Except as contained in this notice, the name of the XFree86 Project shall not
 * be used in advertising or otherwise to promote the sale, use or other deal-
 * ings in this Software without prior written authorization from the XFree86
 * Project.
 */

#include <EGL/egl.h>
#include <EGL/eglext.h>

/* eglGetProcAddress() doesn't work for eglCreateGlobalImageBRCM and friends. */
#define EGL_EGLEXT_PROTOTYPES 1
#include <EGL/eglext_brcm.h>
#undef EGL_EGLEXT_PROTOTYPES

#include <GLES2/gl2.h>
#include <GLES2/gl2ext.h>
#include <bcm_host.h>

#include "videocore-exa.h"
#include "videocore-debug.h"

struct _VideoCoreExa {
	ExaDriverPtr exa;
	EGLDisplay display;
	EGLConfig config;
	EGLContext ctx;
	EGLSurface surf;

	EGL_DISPMANX_WINDOW_T nativeWindow;

	PFNGLEGLIMAGETARGETTEXTURE2DOESPROC glEGLImageTargetTexture2DOES;
};

static inline ScrnInfoPtr
pix2scrn(PixmapPtr pPixmap)
{
	return xf86Screens[(pPixmap)->drawable.pScreen->myNum];
}

static Bool
CheckGLError(ScrnInfoPtr pScrn, const char *context)
{
	GLenum error_code = glGetError ();

	switch (error_code)
	{
		case GL_NO_ERROR:
			return TRUE;
			break;
		case GL_INVALID_ENUM:
			WARNING_MSG("%s: GL_INVALID_ENUM\n", context);
			break;
		case GL_INVALID_VALUE:
			WARNING_MSG("%s: GL_INVALID_VALUE\n", context);
			break;
		case GL_INVALID_OPERATION:
			WARNING_MSG("%s: GL_INVALID_OPERATION\n", context);
			break;
		case GL_OUT_OF_MEMORY:
			WARNING_MSG("%s: GL_OUT_OF_MEMORY\n", context);
			break;
		default:
			WARNING_MSG("%s: unknown error %x\n", context, error_code);
	}

	return FALSE;
}

Bool
VideoCoreExaGetScreenSize(ScrnInfoPtr pScrn,
			  uint32_t *width, uint32_t *height)
{
	int32_t success = graphics_get_display_size(DISPMANX_ID_MAIN_LCD, width, height);

	if (success < 0) {
		ERROR_MSG("graphics_get_display_size failed (%i)", success);
		return FALSE;
	} else {
		return TRUE;
	}
}


static Bool
InitEGL(ScreenPtr pScreen, VideoCoreExaPtr vcExa)
{
	ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
	EGLint num_config;
	uint32_t screen_width, screen_height;

	DISPMANX_DISPLAY_HANDLE_T dispman_display;
	DISPMANX_UPDATE_HANDLE_T dispman_update;

	VC_RECT_T src_rect, dst_rect;

	static const EGLint chooseConfigAttrs[] =
	{
		EGL_RED_SIZE, 8,
		EGL_GREEN_SIZE, 8,
		EGL_BLUE_SIZE, 8,
		EGL_ALPHA_SIZE, 8,
		EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
		EGL_NONE
	};

	static const EGLint createContextAttrs[] =
	{
		EGL_CONTEXT_CLIENT_VERSION, 2,
		EGL_NONE
	};

	static const EGLint createWindowSurfaceAttrs[] =
	{
		EGL_NONE
	};

	DEBUG_MSG("calling bcm_host_init");
	bcm_host_init();

	vcExa->display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
	if (vcExa->display == EGL_NO_DISPLAY) {
		CheckGLError(pScrn, "eglGetDisplay returned EGL_NO_DISPLAY");
		return FALSE;
	}

	DEBUG_MSG("eglInitialize");

	if (!eglInitialize(vcExa->display, NULL, NULL)) {
		CheckGLError(pScrn, "eglInitialize failed");
		return FALSE;
	}

	if (!eglBindAPI(EGL_OPENGL_ES_API)) {
		ERROR_MSG("eglBindAPI(EGL_OPENGL_ES_API) failed. We're doomed.");
		return FALSE;
	}

	if (!eglChooseConfig(vcExa->display, chooseConfigAttrs, &vcExa->config, 1, &num_config)) {
		CheckGLError(pScrn, "eglChooseConfig failed");
		return FALSE;
	}

	vcExa->ctx = eglCreateContext(vcExa->display, vcExa->config, EGL_NO_CONTEXT, createContextAttrs);
	if (vcExa->ctx == EGL_NO_CONTEXT) {
		ERROR_MSG("eglCreateContext failed");
		return FALSE;
	}

	vcExa->glEGLImageTargetTexture2DOES = (void *)
		eglGetProcAddress("glEGLImageTargetTexture2DOES");
	if (vcExa->glEGLImageTargetTexture2DOES == NULL) {
		ERROR_MSG("couldn't find glEGLImageTargetTexture2DOES");
		return FALSE;
	}

	/* TODO: open the correct display, make sure the resolutions match up. */
	if (!VideoCoreExaGetScreenSize(pScrn, &screen_width, &screen_height)) {
		return FALSE;
	}

	DEBUG_MSG("videocore thinks the screen is %u x %u", screen_width, screen_height);

	dst_rect.x = 0;
	dst_rect.y = 0;
	dst_rect.width = screen_width;
	dst_rect.height = screen_height;

	src_rect.x = 0;
	src_rect.y = 0;
	src_rect.width = screen_width << 16;
	src_rect.height = screen_height << 16;

	dispman_display = vc_dispmanx_display_open(DISPMANX_ID_MAIN_LCD);
	dispman_update = vc_dispmanx_update_start( 0 /* priority */ );

	vcExa->nativeWindow.element =
		vc_dispmanx_element_add(dispman_update, dispman_display,
					0/*layer*/, &dst_rect, 0/*src*/,
					&src_rect, DISPMANX_PROTECTION_NONE,
					0 /*alpha*/,
					DISPMANX_FLAGS_CLAMP_NONE,
					DISPMANX_NO_ROTATE);

	vcExa->nativeWindow.width = screen_width;
	vcExa->nativeWindow.height = screen_height;
	vc_dispmanx_update_submit_sync( dispman_update );

	vcExa->surf = eglCreateWindowSurface(vcExa->display, vcExa->config,
						 &vcExa->nativeWindow,
						 createWindowSurfaceAttrs);

	if (vcExa->surf == EGL_NO_SURFACE) {
		CheckGLError(pScrn, "eglCreateWindowSurface failed");
		return FALSE;
	}

	if (!eglMakeCurrent(vcExa->display, vcExa->surf, vcExa->surf, vcExa->ctx)) {
		CheckGLError(pScrn, "eglMakeCurrent failed");
		return FALSE;
	}

	return TRUE;
}

static void
VideoCoreWaitMarker(ScreenPtr pScreen, int marker)
{
	/* TODO */
}

#define GLOBAL_IMAGE_ID0 0
#define GLOBAL_IMAGE_ID1 1
#define GLOBAL_IMAGE_WIDTH 2
#define GLOBAL_IMAGE_HEIGHT 3
#define GLOBAL_IMAGE_PIXEL_FORMAT 4

typedef struct _VideoCorePixmapPriv {
	Bool is_screen_pixmap;

	/* if is_screen_pixmap, then these will all be zeroes */
	EGLint global_image[5];
	EGLImageKHR egl_image;
	GLuint texture_id;

	/* Blob of memory backing the pixmap. If is_screen_pixmap || texture_id
	 * != 0, only set between PrepareAccess and FinishAccess. Otherwise,
	 * allocated in ModifyPixmapHeader and freed in DestroyPixmap.
	 */
	void *data;
} VideoCorePixmapPrivRec, *VideoCorePixmapPrivPtr;

static void *
VideoCoreCreatePixmap2(ScreenPtr pScreen, int width, int height,
                       int depth, int usage_hint, int bitsPerPixel,
                       int *new_fb_pitch)
{
	VideoCorePixmapPrivPtr priv = calloc(sizeof(VideoCorePixmapPrivRec), 1);

	return priv;
}

static Bool
AllocateGlobalImage(ScrnInfoPtr pScrn, int width, int height,
		EGLint *global_image)
{
	int i, *tmp;
	EGLint pixel_format;

	assert(width > 0);
	assert(height > 0);
	assert(global_image != NULL);

	tmp = calloc(sizeof(int), width * height);
	/* Red-fill for potential debugging joy */
	for (i = 0; i != width * height; i++) {
		tmp[i] = 0xff << 8;
	}

	pixel_format = EGL_PIXEL_FORMAT_ARGB_8888_BRCM
		     | EGL_PIXEL_FORMAT_GLES2_TEXTURE_BRCM;
	eglCreateGlobalImageBRCM(width, height, pixel_format,
				 tmp, width * sizeof (int),
				 global_image);
	free(tmp);

	if (!CheckGLError(pScrn, "eglCreateGlobalImageBRCM")) {
		return FALSE;
	}

	global_image[GLOBAL_IMAGE_WIDTH] = width;
	global_image[GLOBAL_IMAGE_HEIGHT] = height;
	global_image[GLOBAL_IMAGE_PIXEL_FORMAT] = pixel_format;
	return TRUE;
}

static Bool
CreateEGLImage(VideoCoreExaPtr vcExa, ScrnInfoPtr pScrn,
	       EGLint *global_image,
	       EGLImageKHR *egl_image_out)
{
	*egl_image_out = eglCreateImageKHR(vcExa->display, EGL_NO_CONTEXT,
					   EGL_NATIVE_PIXMAP_KHR,
					   (EGLClientBuffer) global_image,
					   NULL);
	return CheckGLError(pScrn, "eglCreateImageKHR");
}

static Bool
BindToTexture(VideoCoreExaPtr vcExa, ScrnInfoPtr pScrn, EGLImageKHR egl_image,
	      GLuint *texture_id_out)
{
	glGenTextures(1, texture_id_out);
	glBindTexture(GL_TEXTURE_2D, *texture_id_out);
	vcExa->glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, egl_image);
	glBindTexture(GL_TEXTURE_2D, 0);

	return CheckGLError(pScrn, "glEGLImageTargetTexture2DOES");
}

static void
DestroyGlobalImage(VideoCoreExaPtr vcExa, ScrnInfoPtr pScrn,
		   VideoCorePixmapPrivPtr priv)
{
	if (priv->texture_id != 0) {
		glDeleteTextures(1, &priv->texture_id);
		priv->texture_id = 0;
	}

	if (priv->egl_image != EGL_NO_IMAGE_KHR) {
		if (!eglDestroyImageKHR(vcExa->display, priv->egl_image)) {
			WARNING_MSG("failed to destroy EGLImage");
		}
		priv->egl_image = EGL_NO_IMAGE_KHR;
	}

	if (priv->global_image[GLOBAL_IMAGE_ID0] != 0 &&
	    priv->global_image[GLOBAL_IMAGE_ID1] != 0) {
		if (!eglDestroyGlobalImageBRCM(priv->global_image)) {
			WARNING_MSG("failed to destroy global image (%u, %u)",
				    priv->global_image[GLOBAL_IMAGE_ID0],
				    priv->global_image[GLOBAL_IMAGE_ID1]);
		}
		priv->global_image[GLOBAL_IMAGE_ID0] = 0;
		priv->global_image[GLOBAL_IMAGE_ID1] = 0;
	}
}

static Bool
VideoCoreModifyPixmapHeader(PixmapPtr pPixmap, int width, int height,
			    int depth, int bitsPerPixel, int devKind,
			    pointer pPixData)
{
	VideoCorePixmapPrivPtr priv = exaGetPixmapDriverPrivate(pPixmap);
	ScrnInfoPtr pScrn = pix2scrn(pPixmap);
	VideoCorePtr vcPtr = VIDEOCOREPTR(pScrn);
	VideoCoreExaPtr vcExa = VideoCoreGetExa(vcPtr);

	if (!miModifyPixmapHeader(pPixmap, width, height, depth, bitsPerPixel,
				  devKind, pPixData)) {
		return FALSE;
	}

	if (pPixmap->devKind == 0) {
		pPixmap->devKind = PixmapBytePad(pPixmap->drawable.width,
                                             pPixmap->drawable.depth);
	}

	/* TODO: check if pPixData is the magic value corresponding to the
	 * framebuffer.
	 */
	if (pPixData == VIDEOCORE_FAKE_SCREEN_BITMAP) {
		priv->is_screen_pixmap = TRUE;
		DestroyGlobalImage(vcExa, pScrn, priv);
	} else if (pPixData) {
		/* Unaccelerated pixel soup */
		pPixmap->devPrivate.ptr = pPixData;
		pPixmap->devKind = devKind;

		/* Quoth -omap: "scratch-pixmap (see GetScratchPixmapHeader())
		 * gets recycled, so could have a previous bo!"
		 */
		priv->is_screen_pixmap = FALSE;
		DestroyGlobalImage(vcExa, pScrn, priv);
		return FALSE;
	}

	if (priv->is_screen_pixmap) {
		DEBUG_MSG("ModifyPixmapHeader(%p, %u, %u, %u, %u, %u, %p) called for screen",
			  pPixmap, width, height, depth, bitsPerPixel, devKind, pPixData);
		return TRUE;
	}

	/* passed in values could be zero, indicating that existing values
	 * should be kept.. miModifyPixmapHeader() will deal with that, but
	 * we need to resync to ensure we have the right values in the rest
	 * of this function
	 */
	width	= pPixmap->drawable.width;
	height	= pPixmap->drawable.height;
	depth	= pPixmap->drawable.depth;
	bitsPerPixel = pPixmap->drawable.bitsPerPixel;

	if (bitsPerPixel != 32) {
		DEBUG_MSG("Can't accelerate pixmap %p with bpp %u", pPixmap, bitsPerPixel);
		/* FIXME: we'll presumably need to free previously-allocated
		 * blobs at some point if we're modifying a pixmap */
		priv->data = malloc(pPixmap->devKind * height);
		if (priv->data == NULL) {
			WARNING_MSG("can't allocate %u * %u bytes", pPixmap->devKind, height);
		}
		pPixmap->devPrivate.ptr = priv->data;
		return TRUE; /* ??? */
	}

	if (width * height == 0) {
		DEBUG_MSG("zero area! (%u x %u)", width, height);
		return TRUE;
	}

	if (priv->texture_id != 0) {
		/* FIXME: check if it's already suitable? */
		DestroyGlobalImage(vcExa, pScrn, priv);
	}

	/* FIXME: respect depth/bpp */
	if (AllocateGlobalImage(pScrn, width, height, priv->global_image) &&
	    CreateEGLImage(vcExa, pScrn, priv->global_image, &priv->egl_image) &&
	    BindToTexture(vcExa, pScrn, priv->egl_image, &priv->texture_id)) {
		return TRUE;
	} else {
		/* Okay, never mind. Roll that back. */
		DestroyGlobalImage(vcExa, pScrn, priv);
		return FALSE;
	}
}

static void
VideoCoreDestroyPixmap(ScreenPtr pScreen, void *driverPriv)
{
	ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
	VideoCorePtr vcPtr = VIDEOCOREPTR(pScrn);
	VideoCoreExaPtr vcExa = VideoCoreGetExa(vcPtr);
	VideoCorePixmapPrivPtr priv = driverPriv;

	DestroyGlobalImage(vcExa, pScrn, priv);
	free(priv->data);

	free(priv);
}

/* Sets up @texture_id for glReadPixels; if NULL, reads from the display. */
static void
ReadPixels(ScrnInfoPtr pScrn,
	   GLuint texture_id,
	   int x, int y, int w, int h,
	   char *dst, int dst_pitch)
{
	GLuint sampleFramebuffer = 0;

	if (texture_id != 0) {
		glGenFramebuffers(1, &sampleFramebuffer);
		glBindFramebuffer(GL_FRAMEBUFFER, sampleFramebuffer);
		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
				       GL_TEXTURE_2D, texture_id, 0);
	}

	/* TODO: respect dst_pitch; do we need to turn things upside-down? */
	glReadPixels(x, y, w, h, GL_RGBA, GL_UNSIGNED_BYTE, dst);

	if (texture_id != 0) {
		glDeleteFramebuffers(1, &sampleFramebuffer);
	}
}

/*
 * PrepareAccess() sets up an offscreen pixmap for CPU access. We can't do this
 * efficiently, but we have to implement it. :(
 */
static Bool
VideoCorePrepareAccess(PixmapPtr pPixmap, int index)
{
	VideoCorePixmapPrivPtr priv = exaGetPixmapDriverPrivate(pPixmap);
	ScrnInfoPtr pScrn = pix2scrn(pPixmap);
	unsigned short width, height;

	DEBUG_MSG("called for pixmap %p, is_screen_pixmap %s, texture %u, index %u",
		  pPixmap,
		  priv->is_screen_pixmap ? "true" : "falsetto",
		  priv->texture_id, index);

	if (priv->texture_id == 0 && !priv->is_screen_pixmap) {
		WARNING_MSG("called for boring pixmap %p", pPixmap);
		return FALSE;
	}

	width = pPixmap->drawable.width;
	height = pPixmap->drawable.height;

	/* If we're here, this had better be an XRGB pixmap */
	assert (pPixmap->drawable.bitsPerPixel / 8 == 4);
	/* And we shouldn't get here more than once at a time */
	assert (priv->data == NULL);
	priv->data = malloc(width * height * 4);
	if (!priv->data) {
		ERROR_MSG("couldn't allocate %hu * %hu * 4 bytes!",
			  width, height);
		return FALSE;
	}

	ReadPixels(pScrn, priv->texture_id, 0, 0, width, height, priv->data, 0 /* FIXME: pitch */);
	if (!CheckGLError(pScrn, "PrepareAccess:ReadPixels")) {
		free(priv->data);
		priv->data = NULL;
		return FALSE;
	}

	pPixmap->devPrivate.ptr = priv->data;
	DEBUG_MSG("allocated %p for pixmap %p", priv->data, pPixmap);
	return TRUE;
}

static void
VideoCoreFinishAccess(PixmapPtr pPixmap, int index)
{
	VideoCorePixmapPrivPtr priv = exaGetPixmapDriverPrivate(pPixmap);
	ScrnInfoPtr pScrn = pix2scrn(pPixmap);
	unsigned short width, height;

	if (!priv->is_screen_pixmap) {
		WARNING_MSG("called for a pixmap other than the screen!");
		return;
	}

	DEBUG_MSG("called for screen pixmap, index %u", index);

	width = pPixmap->drawable.width;
	height = pPixmap->drawable.height;

	assert(priv->data != NULL);

	/* FIXME: shade me up */
	(void) (width + height);
	free(priv->data);

	CheckGLError(pScrn, "FinishAccess:glDrawPixels");
}

static Bool
VideoCorePixmapIsOffscreen(PixmapPtr pPixmap)
{
	VideoCorePixmapPrivPtr priv = exaGetPixmapDriverPrivate(pPixmap);

	return priv != NULL &&
		(priv->is_screen_pixmap || priv->texture_id != 0);
}

static Bool
PrepareSolidFail(PixmapPtr pPixmap, int alu, Pixel planemask, Pixel fill_colour)
{
	return FALSE;
}

static Bool
PrepareCopyFail(PixmapPtr pSrc, PixmapPtr pDst, int xdir, int ydir,
		int alu, Pixel planemask)
{
	return FALSE;
}

static Bool
CheckCompositeFail(int op, PicturePtr pSrcPicture, PicturePtr pMaskPicture,
		PicturePtr pDstPicture)
{
	return FALSE;
}

static Bool
PrepareCompositeFail(int op, PicturePtr pSrcPicture, PicturePtr pMaskPicture,
		PicturePtr pDstPicture, PixmapPtr pSrc, PixmapPtr pMask, PixmapPtr pDst)
{
	return FALSE;
}

static Bool
VideoCoreUploadToScreen(PixmapPtr pDst,
			int x, int y, int w, int h,
			char *src, int src_pitch)
{
	VideoCorePixmapPrivPtr priv = exaGetPixmapDriverPrivate(pDst);
	ScrnInfoPtr pScrn = pix2scrn(pDst);

	if (priv->texture_id == 0) {
		return FALSE;
	}

	/* TODO: obey src_pitch */
	glBindTexture(GL_TEXTURE_2D, priv->texture_id);
	glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, w, h,
			GL_RGBA, GL_UNSIGNED_BYTE, src);
	glBindTexture(GL_TEXTURE_2D, 0);

	return CheckGLError(pScrn, "UploadToScreen");
}

static Bool
VideoCoreDownloadFromScreen(PixmapPtr pSrc,
			    int x, int y, int w, int h,
			    char *dst, int dst_pitch)
{
	VideoCorePixmapPrivPtr priv = exaGetPixmapDriverPrivate(pSrc);
	ScrnInfoPtr pScrn = pix2scrn(pSrc);

	if (priv->texture_id == 0 && !priv->is_screen_pixmap) {
		WARNING_MSG("called for boring pixmap %p", pSrc);
		return FALSE;
	}

	ReadPixels(pScrn, priv->texture_id, x, y, w, h, dst, dst_pitch);
	return CheckGLError(pScrn, "DownloadFromScreen");
}

VideoCoreExaPtr
VideoCoreExaInit(ScreenPtr pScreen)
{
	ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
	VideoCoreExaPtr vcExa;
	ExaDriverPtr exa;

	exa = exaDriverAlloc();
	if (!exa) {
		return NULL;
	}

	exa->exa_major = EXA_VERSION_MAJOR;
	exa->exa_minor = EXA_VERSION_MINOR;

	/* Cargo-culted from the OMAP driver. Hooray. */
	exa->pixmapOffsetAlign = 0;
	exa->pixmapPitchAlign = 32 * 4;
	exa->flags = EXA_OFFSCREEN_PIXMAPS |
			EXA_HANDLES_PIXMAPS;
	exa->maxX = 4096;
	exa->maxY = 4096;

	exa->WaitMarker = VideoCoreWaitMarker;
	exa->CreatePixmap2 = VideoCoreCreatePixmap2;
	exa->DestroyPixmap = VideoCoreDestroyPixmap;
	exa->ModifyPixmapHeader = VideoCoreModifyPixmapHeader;

	exa->PrepareAccess = VideoCorePrepareAccess;
	exa->FinishAccess = VideoCoreFinishAccess;
	exa->PixmapIsOffscreen = VideoCorePixmapIsOffscreen;

	/* OMAP fails all these, but maybe we should accelerate them? */
	exa->PrepareSolid = PrepareSolidFail;
	exa->PrepareCopy = PrepareCopyFail;
	exa->CheckComposite = CheckCompositeFail;
	exa->PrepareComposite = PrepareCompositeFail;

	/* We need these because PrepareAccess can fail. */
	exa->UploadToScreen = VideoCoreUploadToScreen;
	exa->DownloadFromScreen = VideoCoreDownloadFromScreen;

	vcExa = calloc(sizeof (*vcExa), 1);
	vcExa->exa = exa;

	if (InitEGL(pScreen, vcExa)) {
		if (!exaDriverInit(pScreen, exa)) {
			ERROR_MSG("exaDriverInit failed");
		}
	}

	return vcExa;
}

/* TODO: free! */