/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Lesser General Public

    License as published by the Free Software Foundation; either

    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public

    License along with this library; if not, write to the Free Software

    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga

    slouken@libsdl.org

*/

#include "SDL_config.h"

#include "SDL_video.h"

#include "../SDL_blit.h"

#include "SDL_fbriva.h"

#include "riva_mmio.h"

#include "riva_regs.h"

static int FifoEmptyCount = 0;

static int FifoFreeCount = 0;

/* Wait for vertical retrace */

static void WaitVBL(_THIS)

{

	volatile Uint8 *port = (Uint8 *)(mapped_io + PCIO_OFFSET + 0x3DA);

	while (  (*port & 0x08) )

		;

	while ( !(*port & 0x08) )

		;

}

static void NV3WaitIdle(_THIS)

{

	RivaRop *Rop = (RivaRop *)(mapped_io + ROP_OFFSET);

	while ( (Rop->FifoFree < FifoEmptyCount) ||

	        (*(mapped_io + PGRAPH_OFFSET + 0x000006B0) & 0x01) )

		;

}

static void NV4WaitIdle(_THIS)

{

	RivaRop *Rop = (RivaRop *)(mapped_io + ROP_OFFSET);

	while ( (Rop->FifoFree < FifoEmptyCount) ||

	        (*(mapped_io + PGRAPH_OFFSET + 0x00000700) & 0x01) )

		;

}

#if 0 /* Not yet implemented? */

/* Sets video mem colorkey and accelerated blit function */

static int SetHWColorKey(_THIS, SDL_Surface *surface, Uint32 key)

{

	return(0);

}

/* Sets per surface hardware alpha value */

static int SetHWAlpha(_THIS, SDL_Surface *surface, Uint8 value)

{

	return(0);

}

#endif /* Not yet implemented */

static int FillHWRect(_THIS, SDL_Surface *dst, SDL_Rect *rect, Uint32 color)

{

	int dstX, dstY;

	int dstW, dstH;

	RivaBitmap *Bitmap = (RivaBitmap *)(mapped_io + BITMAP_OFFSET);

	/* Don't blit to the display surface when switched away */

	if ( switched_away ) {

		return -2; /* no hardware access */

	}

	if ( dst == this->screen ) {

		SDL_mutexP(hw_lock);

	}

	/* Set up the X/Y base coordinates */

	dstW = rect->w;

	dstH = rect->h;

	FB_dst_to_xy(this, dst, &dstX, &dstY);

	/* Adjust for the current rectangle */

	dstX += rect->x;

	dstY += rect->y;

	RIVA_FIFO_FREE(Bitmap, 1);

	Bitmap->Color1A = color;

	RIVA_FIFO_FREE(Bitmap, 2);

	Bitmap->UnclippedRectangle[0].TopLeft     = (dstX << 16) | dstY; 

	Bitmap->UnclippedRectangle[0].WidthHeight = (dstW << 16) | dstH;

	FB_AddBusySurface(dst);

	if ( dst == this->screen ) {

		SDL_mutexV(hw_lock);

	}

	return(0);

}

static int HWAccelBlit(SDL_Surface *src, SDL_Rect *srcrect,

                       SDL_Surface *dst, SDL_Rect *dstrect)

{

	SDL_VideoDevice *this = current_video;

	int srcX, srcY;

	int dstX, dstY;

	int dstW, dstH;

	RivaScreenBlt *Blt = (RivaScreenBlt *)(mapped_io + BLT_OFFSET);

	/* FIXME: For now, only blit to display surface */

	if ( dst->pitch != SDL_VideoSurface->pitch ) {

		return(src->map->sw_blit(src, srcrect, dst, dstrect));

	}

	/* Don't blit to the display surface when switched away */

	if ( switched_away ) {

		return -2; /* no hardware access */

	}

	if ( dst == this->screen ) {

		SDL_mutexP(hw_lock);

	}

	/* Calculate source and destination base coordinates (in pixels) */

	dstW = dstrect->w;

	dstH = dstrect->h;

	FB_dst_to_xy(this, src, &srcX, &srcY);

	FB_dst_to_xy(this, dst, &dstX, &dstY);

	/* Adjust for the current blit rectangles */

	srcX += srcrect->x;

	srcY += srcrect->y;

	dstX += dstrect->x;

	dstY += dstrect->y;

	RIVA_FIFO_FREE(Blt, 3);

	Blt->TopLeftSrc  = (srcY << 16) | srcX;

	Blt->TopLeftDst  = (dstY << 16) | dstX;

	Blt->WidthHeight = (dstH  << 16) | dstW;

	FB_AddBusySurface(src);

	FB_AddBusySurface(dst);

	if ( dst == this->screen ) {

		SDL_mutexV(hw_lock);

	}

	return(0);

}

static int CheckHWBlit(_THIS, SDL_Surface *src, SDL_Surface *dst)

{

	int accelerated;

	/* Set initial acceleration on */

	src->flags |= SDL_HWACCEL;

	/* Set the surface attributes */

	if ( (src->flags & SDL_SRCALPHA) == SDL_SRCALPHA ) {

		if ( ! this->info.blit_hw_A ) {

			src->flags &= ~SDL_HWACCEL;

		}

	}

	if ( (src->flags & SDL_SRCCOLORKEY) == SDL_SRCCOLORKEY ) {

		if ( ! this->info.blit_hw_CC ) {

			src->flags &= ~SDL_HWACCEL;

		}

	}

	/* Check to see if final surface blit is accelerated */

	accelerated = !!(src->flags & SDL_HWACCEL);

	if ( accelerated ) {

		src->map->hw_blit = HWAccelBlit;

	}

	return(accelerated);

}

void FB_RivaAccel(_THIS, __u32 card)

{

	RivaRop *Rop = (RivaRop *)(mapped_io + ROP_OFFSET);

	/* We have hardware accelerated surface functions */

	this->CheckHWBlit = CheckHWBlit;

	wait_vbl = WaitVBL;

	switch (card) {

	    case FB_ACCEL_NV3:

		wait_idle = NV3WaitIdle;

		break;

	    case FB_ACCEL_NV4:

		wait_idle = NV4WaitIdle;

		break;

	    default:

		/* Hmm... FIXME */

		break;

	}

	FifoEmptyCount = Rop->FifoFree;

	/* The Riva has an accelerated color fill */

	this->info.blit_fill = 1;

	this->FillHWRect = FillHWRect;

	/* The Riva has accelerated normal and colorkey blits. */

	this->info.blit_hw = 1;

#if 0 /* Not yet implemented? */

	this->info.blit_hw_CC = 1;

	this->SetHWColorKey = SetHWColorKey;

#endif

#if 0 /* Not yet implemented? */

	/* The Riva has an accelerated alpha blit */

	this->info.blit_hw_A = 1;

	this->SetHWAlpha = SetHWAlpha;

#endif

}