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/* $XFree86: xc/programs/Xserver/hw/xfree86/drivers/nsc/gfx/rndr_gu1.c,v 1.1 2002/12/10 15:12:27 alanh Exp $ */
/*
 * $Workfile: rndr_gu1.c $
 *
 * This file contains routines to program the 2D acceleration hardware for
 * the first generation graphics unit (GXLV, SC1200).
 * 
 *    gfx_set_bpp            
 *    gfx_set_solid_pattern  
 *    gfx_set_mono_pattern
 *    gfx_set_color_pattern
 *    gfx_set_solid_source  
 *    gfx_set_mono_source
 *    gfx_set_raster_operation
 *    gfx_pattern_fill
 *    gfx_screen_to_screen_blt
 *    gfx_screen_to_screen_xblt
 *    gfx_color_bitmap_to_screen_blt
 *    gfx_color_bitmap_to_screen_xblt
 *    gfx_mono_bitmap_to_screen_blt
 *    gfx_bresenham_line 
 *    gfx_wait_until_idle   
 *
 * NSC_LIC_ALTERNATIVE_PREAMBLE
 *
 * Revision 1.0
 *
 * National Semiconductor Alternative GPL-BSD License
 *
 * National Semiconductor Corporation licenses this software 
 * ("Software"):
 *
 *      Durango
 *
 * under one of the two following licenses, depending on how the 
 * Software is received by the Licensee.
 * 
 * If this Software is received as part of the Linux Framebuffer or
 * other GPL licensed software, then the GPL license designated 
 * NSC_LIC_GPL applies to this Software; in all other circumstances 
 * then the BSD-style license designated NSC_LIC_BSD shall apply.
 *
 * END_NSC_LIC_ALTERNATIVE_PREAMBLE */

/* NSC_LIC_BSD
 *
 * National Semiconductor Corporation Open Source License for Durango
 *
 * (BSD License with Export Notice)
 *
 * Copyright (c) 1999-2001
 * National Semiconductor Corporation.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions 
 * are met: 
 *
 *   * Redistributions of source code must retain the above copyright 
 *     notice, this list of conditions and the following disclaimer. 
 *
 *   * Redistributions in binary form must reproduce the above 
 *     copyright notice, this list of conditions and the following 
 *     disclaimer in the documentation and/or other materials provided 
 *     with the distribution. 
 *
 *   * Neither the name of the National Semiconductor Corporation nor 
 *     the names of its contributors may be used to endorse or promote 
 *     products derived from this software without specific prior 
 *     written permission. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
 * NATIONAL SEMICONDUCTOR CORPORATION OR CONTRIBUTORS BE LIABLE FOR ANY 
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE,
 * INTELLECTUAL PROPERTY INFRINGEMENT, OR OTHERWISE) ARISING IN ANY WAY 
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
 * OF SUCH DAMAGE.
 *
 * EXPORT LAWS: THIS LICENSE ADDS NO RESTRICTIONS TO THE EXPORT LAWS OF 
 * YOUR JURISDICTION. It is licensee's responsibility to comply with 
 * any export regulations applicable in licensee's jurisdiction. Under 
 * CURRENT (2001) U.S. export regulations this software 
 * is eligible for export from the U.S. and can be downloaded by or 
 * otherwise exported or reexported worldwide EXCEPT to U.S. embargoed 
 * destinations which include Cuba, Iraq, Libya, North Korea, Iran, 
 * Syria, Sudan, Afghanistan and any other country to which the U.S. 
 * has embargoed goods and services. 
 *
 * END_NSC_LIC_BSD */

/* NSC_LIC_GPL
 *
 * National Semiconductor Corporation Gnu General Public License for Durango
 *
 * (GPL License with Export Notice)
 *
 * Copyright (c) 1999-2001
 * National Semiconductor Corporation.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted under the terms of the GNU General 
 * Public License as published by the Free Software Foundation; either 
 * version 2 of the License, or (at your option) any later version  
 *
 * In addition to the terms of the GNU General Public License, neither 
 * the name of the National Semiconductor Corporation nor the names of 
 * its contributors may be used to endorse or promote products derived 
 * from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
 * NATIONAL SEMICONDUCTOR CORPORATION OR CONTRIBUTORS BE LIABLE FOR ANY 
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE, 
 * INTELLECTUAL PROPERTY INFRINGEMENT, OR OTHERWISE) ARISING IN ANY WAY 
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
 * OF SUCH DAMAGE. See the GNU General Public License for more details. 
 *
 * EXPORT LAWS: THIS LICENSE ADDS NO RESTRICTIONS TO THE EXPORT LAWS OF 
 * YOUR JURISDICTION. It is licensee's responsibility to comply with 
 * any export regulations applicable in licensee's jurisdiction. Under 
 * CURRENT (2001) U.S. export regulations this software 
 * is eligible for export from the U.S. and can be downloaded by or 
 * otherwise exported or reexported worldwide EXCEPT to U.S. embargoed 
 * destinations which include Cuba, Iraq, Libya, North Korea, Iran, 
 * Syria, Sudan, Afghanistan and any other country to which the U.S. 
 * has embargoed goods and services. 
 *
 * You should have received a copy of the GNU General Public License 
 * along with this file; if not, write to the Free Software Foundation, 
 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 
 *
 * END_NSC_LIC_GPL */

void gu1_set_bpp(unsigned short bpp);
void gu1_set_solid_pattern(unsigned long color);
void gu1_set_mono_pattern(unsigned long bgcolor, unsigned long fgcolor,
			  unsigned long data0, unsigned long data1,
			  unsigned char transparency);
void gu1_set_color_pattern(unsigned long bgcolor, unsigned long fgcolor,
			   unsigned long data0, unsigned long data1,
			   unsigned long data2, unsigned long data3,
			   unsigned char transparency);
void gu1_load_color_pattern_line(short y, unsigned long *pattern_8x8);
void gu1_set_solid_source(unsigned long color);
void gu1_set_mono_source(unsigned long bgcolor, unsigned long fgcolor,
			 unsigned short transparent);
void gu1_set_pattern_flags(unsigned short flags);
void gu1_set_raster_operation(unsigned char rop);
void gu1_pattern_fill(unsigned short x, unsigned short y,
		      unsigned short width, unsigned short height);
void gu1_color_pattern_fill(unsigned short x, unsigned short y,
			    unsigned short width, unsigned short height,
			    unsigned long *pattern);
void gu1_screen_to_screen_blt(unsigned short srcx, unsigned short srcy,
			      unsigned short dstx, unsigned short dsty,
			      unsigned short width, unsigned short height);
void gu1_screen_to_screen_xblt(unsigned short srcx, unsigned short srcy,
			       unsigned short dstx, unsigned short dsty,
			       unsigned short width, unsigned short height,
			       unsigned long color);
void gu1_color_bitmap_to_screen_blt(unsigned short srcx, unsigned short srcy,
				    unsigned short dstx, unsigned short dsty,
				    unsigned short width,
				    unsigned short height,
				    unsigned char *data, long pitch);
void gu1_color_bitmap_to_screen_xblt(unsigned short srcx, unsigned short srcy,
				     unsigned short dstx, unsigned short dsty,
				     unsigned short width,
				     unsigned short height,
				     unsigned char *data, long pitch,
				     unsigned long color);
void gu1_mono_bitmap_to_screen_blt(unsigned short srcx, unsigned short srcy,
				   unsigned short dstx, unsigned short dsty,
				   unsigned short width,
				   unsigned short height, unsigned char *data,
				   short pitch);
void gu1_text_blt(unsigned short dstx, unsigned short dsty,
		  unsigned short width, unsigned short height,
		  unsigned char *data);
void gu1_bresenham_line(unsigned short x, unsigned short y,
			unsigned short length, unsigned short initerr,
			unsigned short axialerr, unsigned short diagerr,
			unsigned short flags);
void gu1_wait_until_idle(void);

#if GFX_NO_IO_IN_WAIT_MACROS
#define GFX_WAIT_PENDING while(READ_REG16(GP_BLIT_STATUS) & BS_BLIT_PENDING) { ; }
#define GFX_WAIT_BUSY while(READ_REG16(GP_BLIT_STATUS) & BS_BLIT_BUSY) { ; }
#define GFX_WAIT_PIPELINE while (READ_REG16(GP_BLIT_STATUS) & BS_PIPELINE_BUSY) { ; }
#else
#define GFX_WAIT_PENDING while(READ_REG16(GP_BLIT_STATUS) & BS_BLIT_PENDING) { INB (0x80); }
#define GFX_WAIT_BUSY while(READ_REG16(GP_BLIT_STATUS) & BS_BLIT_BUSY) { INB (0x80); }
#define GFX_WAIT_PIPELINE while (READ_REG16(GP_BLIT_STATUS) & BS_PIPELINE_BUSY) { INB (0x80); }
#endif

void gu1_detect_blt_buffer_base(void);
int gu1_test_blt_pending(void);
void gu1_solid_fill(unsigned short x, unsigned short y,
		    unsigned short width, unsigned short height,
		    unsigned long color);

/*---------------------------------------------------------------------------
 * GFX_SET_BPP
 *
 * This routine sets the bits per pixel value in the graphics engine.
 * It is also stored in a static variable to use in the future calls to 
 * the rendering routines.
 *---------------------------------------------------------------------------
 */
#if GFX_2DACCEL_DYNAMIC
void
gu1_set_bpp(unsigned short bpp)
#else
void
gfx_set_bpp(unsigned short bpp)
#endif
{
   int control = 0;
   unsigned short pitch = gfx_get_display_pitch();

   GFXbpp = bpp;

   /* DETECT BASE ADDRESSES FOR BLT BUFFERS */
   /* Different for 2K or 3K of scratchpad.  Also need to calculate */
   /* the number of pixels that can fit in a BLT buffer - need to */
   /* subtract 16 for alignment considerations.  The 2K case, for */
   /* example, is 816 bytes wide, allowing 800 pixels in 8 BPP, which */
   /* means rendering operations won't be split for 800x600. */

   gu1_detect_blt_buffer_base();
   GFXbufferWidthPixels = GFXbb1Base - GFXbb0Base - 16;
   if (bpp > 8) {
      /* If 16bpp, divide GFXbufferWidthPixels by 2 */
      GFXbufferWidthPixels >>= 1;
   }

   /* SET THE GRAPHICS CONTROLLER BPP AND PITCH */
   if (bpp > 8) {
      /* Set the 16bpp bit if necessary */
      control = BC_16BPP;
   }
   if ((gfx_cpu_version == GFX_CPU_PYRAMID) && (pitch > 2048)) {
      control |= BC_FB_WIDTH_4096;
   } else if (pitch > 1024) {
      control |= BC_FB_WIDTH_2048;
   }
   GFX_WAIT_BUSY;
   WRITE_REG32(GP_BLIT_STATUS, control);
}

/*
//---------------------------------------------------------------------------
// GFX_SET_SOLID_SOURCE
//
// This routine is used to specify a solid source color.  For the Xfree96
// display driver, the source color is used to specify a planemask and the 
// ROP is adjusted accordingly.
//---------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_set_solid_source(unsigned long color)
#else
void
gfx_set_solid_source(unsigned long color)
#endif
{
   /* CLEAR TRANSPARENCY FLAG */

   GFXsourceFlags = 0;

   /* FORMAT 8 BPP COLOR */
   /* GX requires 8BPP color data be duplicated into bits [15:8]. */

   if (GFXbpp == 8) {
      color &= 0x00FF;
      color |= (color << 8);
   }

   /* POLL UNTIL ABLE TO WRITE THE SOURCE COLOR */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_SRC_COLOR_0, (unsigned short)color);
   WRITE_REG16(GP_SRC_COLOR_1, (unsigned short)color);
}

/*
//---------------------------------------------------------------------------
// GFX_SET_MONO_SOURCE
//
// This routine is used to specify the monochrome source colors.  
// It must be called *after* loading any pattern data (those routines 
// clear the source flags).
//---------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_set_mono_source(unsigned long bgcolor, unsigned long fgcolor,
		    unsigned short transparent)
#else
void
gfx_set_mono_source(unsigned long bgcolor, unsigned long fgcolor,
		    unsigned short transparent)
#endif
{
   /* SET TRANSPARENCY FLAG */

   GFXsourceFlags = transparent ? RM_SRC_TRANSPARENT : 0;

   /* FORMAT 8 BPP COLOR */
   /* GX requires 8BPP color data be duplicated into bits [15:8]. */

   if (GFXbpp == 8) {
      bgcolor &= 0x00FF;
      bgcolor |= (bgcolor << 8);
      fgcolor &= 0x00FF;
      fgcolor |= (fgcolor << 8);
   }

   /* POLL UNTIL ABLE TO WRITE THE SOURCE COLOR */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_SRC_COLOR_0, (unsigned short)bgcolor);
   WRITE_REG16(GP_SRC_COLOR_1, (unsigned short)fgcolor);
}

/*
//---------------------------------------------------------------------------
// GFX_SET_SOLID_PATTERN
//
// This routine is used to specify a solid pattern color.  It is called 
// before performing solid rectangle fills or more complicated BLTs that 
// use a solid pattern color. 
//
// The driver should always call "gfx_load_raster_operation" after a call 
// to this routine to make sure that the pattern flags are set appropriately.
//---------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_set_solid_pattern(unsigned long color)
#else
void
gfx_set_solid_pattern(unsigned long color)
#endif
{
   /* CLEAR TRANSPARENCY FLAG */

   GFXsourceFlags = 0;

   /* SET PATTERN FLAGS */

   GFXpatternFlags = 0;

   /* FORMAT 8 BPP COLOR */
   /* GX requires 8BPP color data be duplicated into bits [15:8]. */

   if (GFXbpp == 8) {
      color &= 0x00FF;
      color |= (color << 8);
   }

   /* SAVE THE REFORMATTED COLOR FOR LATER */
   /* Used to call the "GFX_solid_fill" routine for special cases. */

   GFXsavedColor = color;

   /* POLL UNTIL ABLE TO WRITE THE PATTERN COLOR */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_PAT_COLOR_0, (unsigned short)color);
}

/*
//---------------------------------------------------------------------------
// GFX_SET_MONO_PATTERN
//
// This routine is used to specify a monochrome pattern. 
//---------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_set_mono_pattern(unsigned long bgcolor, unsigned long fgcolor,
		     unsigned long data0, unsigned long data1,
		     unsigned char transparent)
#else
void
gfx_set_mono_pattern(unsigned long bgcolor, unsigned long fgcolor,
		     unsigned long data0, unsigned long data1,
		     unsigned char transparent)
#endif
{
   /* CLEAR TRANSPARENCY FLAG */

   GFXsourceFlags = 0;

   /* SET PATTERN FLAGS */

   GFXpatternFlags = transparent ? RM_PAT_MONO | RM_PAT_TRANSPARENT :
	 RM_PAT_MONO;

   /* FORMAT 8 BPP COLOR */
   /* GXm requires 8BPP color data be duplicated into bits [15:8]. */

   if (GFXbpp == 8) {
      bgcolor &= 0x00FF;
      bgcolor |= (bgcolor << 8);
      fgcolor &= 0x00FF;
      fgcolor |= (fgcolor << 8);
   }

   /* POLL UNTIL ABLE TO WRITE THE PATTERN COLORS AND DATA */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_PAT_COLOR_0, (unsigned short)bgcolor);
   WRITE_REG16(GP_PAT_COLOR_1, (unsigned short)fgcolor);
   WRITE_REG32(GP_PAT_DATA_0, data0);
   WRITE_REG32(GP_PAT_DATA_1, data1);
}

/*
//---------------------------------------------------------------------------
// GFX_SET_COLOR_PATTERN
//
// This routine is used to specify a color pattern. 
//---------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_set_color_pattern(unsigned long bgcolor, unsigned long fgcolor,
		      unsigned long data0, unsigned long data1,
		      unsigned long data2, unsigned long data3,
		      unsigned char transparent)
#else
void
gfx_set_color_pattern(unsigned long bgcolor, unsigned long fgcolor,
		      unsigned long data0, unsigned long data1,
		      unsigned long data2, unsigned long data3,
		      unsigned char transparent)
#endif
{
   /* CLEAR TRANSPARENCY FLAG */

   GFXsourceFlags = 0;

   /* SET PATTERN FLAGS */

   GFXpatternFlags = transparent ? RM_PAT_MONO | RM_PAT_TRANSPARENT :
	 RM_PAT_MONO;

   GFXpatternFlags |= RM_PAT_COLOR;
   /* FORMAT 8 BPP COLOR */
   /* GXm requires 8BPP color data be duplicated into bits [15:8]. */

   if (GFXbpp == 8) {
      bgcolor &= 0x00FF;
      bgcolor |= (bgcolor << 8);
      fgcolor &= 0x00FF;
      fgcolor |= (fgcolor << 8);
   }

   /* POLL UNTIL ABLE TO WRITE THE PATTERN COLORS AND DATA */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_PAT_COLOR_0, (unsigned short)bgcolor);
   WRITE_REG16(GP_PAT_COLOR_1, (unsigned short)fgcolor);
   WRITE_REG32(GP_PAT_DATA_0, data0);
   WRITE_REG32(GP_PAT_DATA_1, data1);
   if (GFXbpp > 8) {
      WRITE_REG32(GP_PAT_DATA_2, data2);
      WRITE_REG32(GP_PAT_DATA_3, data3);
   }
}

/*
//---------------------------------------------------------------------------
// GFX_LOAD_COLOR_PATTERN_LINE
//
// This routine is used to load a single line of a 8x8 color pattern.   
//---------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_load_color_pattern_line(short y, unsigned long *pattern_8x8)
#else
void
gfx_load_color_pattern_line(short y, unsigned long *pattern_8x8)
#endif
{
   /* CLEAR TRANSPARENCY FLAG */

   GFXsourceFlags = 0;

   /* SET PATTERN FLAGS */

   GFXpatternFlags = RM_PAT_COLOR;

   y &= 7;

   if (GFXbpp > 8)
      pattern_8x8 += (y << 2);
   else
      pattern_8x8 += (y << 1);

   /* POLL UNTIL ABLE TO WRITE THE PATTERN COLORS AND DATA */

   GFX_WAIT_PENDING;
   WRITE_REG32(GP_PAT_DATA_0, pattern_8x8[0]);
   WRITE_REG32(GP_PAT_DATA_1, pattern_8x8[1]);
   if (GFXbpp > 8) {
      WRITE_REG32(GP_PAT_DATA_2, pattern_8x8[2]);
      WRITE_REG32(GP_PAT_DATA_3, pattern_8x8[3]);
   }
}

/*
//---------------------------------------------------------------------------
// GFX_SET_RASTER_OPERATION
//
// This routine loads the specified raster operation.  It sets the pattern
// flags appropriately.
//---------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_set_raster_operation(unsigned char rop)
#else
void
gfx_set_raster_operation(unsigned char rop)
#endif
{
   unsigned short rop16;

   /* GENERATE 16-BIT VERSION OF ROP WITH PATTERN FLAGS */

   rop16 = (unsigned short)rop | GFXpatternFlags;
   if ((rop & 0x33) ^ ((rop >> 2) & 0x33))
      rop16 |= GFXsourceFlags;

   /* SAVE ROP FOR LATER COMPARISONS */
   /* Need to have the pattern flags included */

   GFXsavedRop = rop16;

   /* SET FLAG INDICATING ROP REQUIRES DESTINATION DATA */
   /* True if even bits (0:2:4:6) do not equal the correspinding */
   /* even bits (1:3:5:7). */

   GFXusesDstData = ((rop & 0x55) ^ ((rop >> 1) & 0x55));

   /* POLL UNTIL ABLE TO WRITE THE PATTERN COLOR */
   /* Only one operation can be pending at a time. */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_RASTER_MODE, rop16);
}

/*
//---------------------------------------------------------------------------
// GFX_SOLID_FILL
//
// This routine MUST be used when performing a solid rectangle fill with 
// the ROPs of PATCOPY (0xF0), BLACKNESS (0x00), WHITENESS (0xFF), or 
// PATINVERT (0x0F).  There is a bug in GXm for these cases that requires a 
// workaround.  
//
// For BLACKNESS (ROP = 0x00), set the color to 0x0000.  
// For WHITENESS (ROP = 0xFF), set the color to 0xFFFF.
// For PATINVERT (ROP = 0x0F), invert the desired color.
//
//      X               screen X position (left)
//      Y               screen Y position (top)
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//      COLOR           fill color
//
// THIS ROUTINE SHOULD NOT BE DIRECTLY CALLED FROM THE DRIVER.  The driver 
// should always use GFX_pattern_fill and let that routine call this one
// when approipriate.  This is to hide quirks specific to MediaGX hardware.
//---------------------------------------------------------------------------
*/
void
gu1_solid_fill(unsigned short x, unsigned short y,
	       unsigned short width, unsigned short height,
	       unsigned long color)
{
   unsigned short section;

   /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS */
   /* Only one operation can be pending at a time. */

   GFX_WAIT_PENDING;

   /* SET REGISTERS TO DRAW RECTANGLE */

   WRITE_REG16(GP_DST_XCOOR, x);
   WRITE_REG16(GP_DST_YCOOR, y);
   WRITE_REG16(GP_HEIGHT, height);
   WRITE_REG16(GP_RASTER_MODE, 0x00F0);	/* PATCOPY */
   WRITE_REG16(GP_PAT_COLOR_0, (unsigned short)color);

   /* CHECK WIDTH FOR GX BUG WORKAROUND */

   if (width <= 16) {
      /* OK TO DRAW SMALL RECTANGLE IN ONE PASS */

      WRITE_REG16(GP_WIDTH, width);
      WRITE_REG16(GP_BLIT_MODE, 0);
   } else {
      /* DRAW FIRST PART OF RECTANGLE */
      /* Get to a 16 pixel boundary. */

      section = 0x10 - (x & 0x0F);
      WRITE_REG16(GP_WIDTH, section);
      WRITE_REG16(GP_BLIT_MODE, 0);

      /* POLL UNTIL ABLE TO LOAD THE SECOND RECTANGLE */

      GFX_WAIT_PENDING;
      WRITE_REG16(GP_DST_XCOOR, x + section);
      WRITE_REG16(GP_DST_YCOOR, y);
      WRITE_REG16(GP_WIDTH, width - section);
      WRITE_REG16(GP_BLIT_MODE, 0);
   }
}

/*
//----------------------------------------------------------------------------
// GFX_PATTERN_FILL
//
// This routine is used to fill a rectangular region.  The pattern must 
// be previously loaded using one of GFX_load_*_pattern routines.  Also, the 
// raster operation must be previously specified using the 
// "GFX_load_raster_operation" routine.
//
//      X               screen X position (left)
//      Y               screen Y position (top)
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_pattern_fill(unsigned short x, unsigned short y,
		 unsigned short width, unsigned short height)
#else
void
gfx_pattern_fill(unsigned short x, unsigned short y,
		 unsigned short width, unsigned short height)
#endif
{
   unsigned short section, buffer_width, blit_mode;

   /* CHECK IF OPTIMIZED SOLID CASES */
   /* Check all 16 bits of the ROP to include solid pattern flags. */

   switch (GFXsavedRop) {
      /* CHECK FOR SPECIAL CASES WITHOUT DESTINATION DATA */
      /* Need hardware workaround for fast "burst write" cases. */

   case 0x00F0:
      gu1_solid_fill(x, y, width, height, (unsigned short)GFXsavedColor);
      break;
   case 0x000F:
      gu1_solid_fill(x, y, width, height, (unsigned short)~GFXsavedColor);
      break;
   case 0x0000:
      gu1_solid_fill(x, y, width, height, 0x0000);
      break;
   case 0x00FF:
      gu1_solid_fill(x, y, width, height, 0xFFFF);
      break;

      /* REMAINING CASES REQUIRE DESTINATION DATA OR NOT SOLID COLOR */

   default:

      /* DETERMINE BLT MODE VALUE */
      /* Still here for non-solid patterns without destination data. */

      blit_mode = GFXusesDstData ? BM_READ_DST_FB0 : 0;

      /* SET SOURCE EXPANSION MODE */
      /* If the ROP requires source data, then the source data is all 1's */
      /* and then expanded into the desired color in GP_SRC_COLOR_1. */

      blit_mode |= BM_SOURCE_EXPAND;

      /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS */
      /* Write the registers that do not change for each section. */

      GFX_WAIT_PENDING;
      WRITE_REG16(GP_HEIGHT, height);

      /* SINCE ONLY DESTINATION DATA, WE CAN USE BOTH BB0 AND BB1. */
      /* Therefore, width available = BLT buffer width * 2. */

      buffer_width = GFXbufferWidthPixels << 1;

      /* REPEAT UNTIL FINISHED WITH RECTANGLE */
      /* Perform BLT in vertical sections, as wide as the BLT buffer */
      /* allows.  Hardware does not split the operations, so */
      /* software must do it to avoid large scanlines that would */
      /* overflow the BLT buffers. */

      while (width > 0) {
	 /* DETERMINE WIDTH OF SECTION */

	 if (width > buffer_width)
	    section = buffer_width;
	 else
	    section = width;

	 /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS */

	 GFX_WAIT_PENDING;
	 WRITE_REG16(GP_DST_XCOOR, x);
	 WRITE_REG16(GP_DST_YCOOR, y);
	 WRITE_REG16(GP_WIDTH, section);
	 WRITE_REG16(GP_BLIT_MODE, blit_mode);

	 /* ADJUST PARAMETERS FOR NEXT SECTION */

	 width -= section;
	 x += section;
      }
      break;
   }
}

/*
//----------------------------------------------------------------------------
// GFX_COLOR_PATTERN_FILL
//
// This routine is used to render a rectangle using the current raster 
// operation and the specified color pattern.  It allows an 8x8 color 
// pattern to be rendered without multiple calls to the gfx_set_color_pattern
// and gfx_pattern_fill routines.
//
//      X               screen X position (left)
//      Y               screen Y position (top)
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//      *PATTERN		pointer to 8x8 color pattern data
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_color_pattern_fill(unsigned short x, unsigned short y,
		       unsigned short width, unsigned short height,
		       unsigned long *pattern)
#else
void
gfx_color_pattern_fill(unsigned short x, unsigned short y,
		       unsigned short width, unsigned short height,
		       unsigned long *pattern)
#endif
{
   unsigned short blit_mode, passes, cur_y, pat_y, i;
   unsigned short buffer_width, line_width;
   unsigned short bpp_shift, section, cur_x;

   /* SET APPROPRIATE INCREMENT */

   bpp_shift = (GFXbpp > 8) ? 2 : 1;

   /* SET DESTINATION REQUIRED */

   blit_mode = GFXusesDstData ? BM_READ_DST_FB0 : 0;

   /* SET SOURCE EXPANSION */

   blit_mode |= BM_SOURCE_EXPAND;

   /* OVERRIDE RASTER MODE TO FORCE A COLOR PATTERN */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_RASTER_MODE,
	       (GFXsavedRop & ~RM_PAT_MASK & ~RM_PAT_TRANSPARENT) |
	       RM_PAT_COLOR);

   /* WRITE THE REGISTERS THAT DO NOT CHANGE         */
   /* If destination data is required, the width and */
   /* x position will be overwritten.                */

   WRITE_REG16(GP_HEIGHT, 1);
   WRITE_REG16(GP_WIDTH, width);
   WRITE_REG16(GP_DST_XCOOR, x);

   /* THE ENTIRE PATTERN WILL NOT BE DRAWN IF THE HEIGHT IS LESS THAN 8 */

   passes = (height < 8) ? height : 8;

   /* SINCE ONLY DESTINATION DATA, WE CAN USE BOTH BB0 AND BB1. */
   /* Therefore, width available = BLT buffer width * 2. */

   buffer_width = GFXbufferWidthPixels << 1;

   for (i = 0; i < passes; i++) {
      pat_y = ((y + i) & 7) << bpp_shift;
      cur_y = y + i;

      /* WRITE THE PATTERN DATA FOR THE ACTIVE LINE */

      GFX_WAIT_PENDING;
      WRITE_REG32(GP_PAT_DATA_0, pattern[pat_y]);
      WRITE_REG32(GP_PAT_DATA_1, pattern[pat_y + 1]);

      if (GFXbpp > 8) {
	 WRITE_REG32(GP_PAT_DATA_2, pattern[pat_y + 2]);
	 WRITE_REG32(GP_PAT_DATA_3, pattern[pat_y + 3]);
      }

      /* SPLIT BLT LINE INTO SECTIONS IF REQUIRED              */
      /* If no destination data is required, we can ignore     */
      /* the BLT buffers.  Otherwise, we must separate the BLT */
      /* so as not to overflow the buffers                     */

      if (blit_mode & BM_READ_DST_BB0) {
	 line_width = width;
	 cur_x = x;

	 while (line_width) {
	    section = (line_width > buffer_width) ? buffer_width : line_width;
	    cur_y = y + i;

	    GFX_WAIT_PENDING;
	    WRITE_REG16(GP_DST_XCOOR, cur_x);
	    WRITE_REG16(GP_WIDTH, section);

	    while (cur_y < y + height) {
	       GFX_WAIT_PENDING;
	       WRITE_REG16(GP_DST_YCOOR, cur_y);
	       WRITE_REG16(GP_BLIT_MODE, blit_mode);
	       cur_y += 8;
	    }

	    cur_x += section;
	    line_width -= section;
	 }

      } else {
	 while (cur_y < y + height) {
	    GFX_WAIT_PENDING;
	    WRITE_REG16(GP_DST_YCOOR, cur_y);
	    WRITE_REG16(GP_BLIT_MODE, blit_mode);
	    cur_y += 8;
	 }
      }

   }

   /* RESTORE ORIGINAL ROP AND FLAGS */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_RASTER_MODE, GFXsavedRop);

}

/*
//----------------------------------------------------------------------------
// SCREEN TO SCREEN BLT
//
// This routine should be used to perform a screen to screen BLT when the 
// ROP does not require destination data.
//
//      SRCX            screen X position to copy from
//      SRCY            screen Y position to copy from
//      DSTX            screen X position to copy to
//      DSTY            screen Y position to copy to
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_screen_to_screen_blt(unsigned short srcx, unsigned short srcy,
			 unsigned short dstx, unsigned short dsty,
			 unsigned short width, unsigned short height)
#else
void
gfx_screen_to_screen_blt(unsigned short srcx, unsigned short srcy,
			 unsigned short dstx, unsigned short dsty,
			 unsigned short width, unsigned short height)
#endif
{
   unsigned short section, buffer_width;
   unsigned short blit_mode;

   /* CHECK IF RASTER OPERATION REQUIRES DESTINATION DATA */

   blit_mode = GFXusesDstData ? BM_READ_DST_FB1 | BM_READ_SRC_FB :
	 BM_READ_SRC_FB;

   /* CHECK Y DIRECTION */
   /* Hardware has support for negative Y direction. */

   if (dsty > srcy) {
      blit_mode |= BM_REVERSE_Y;
      srcy += height - 1;
      dsty += height - 1;
   }

   /* CHECK X DIRECTION */
   /* Hardware does not support negative X direction since at the time */
   /* of development all supported resolutions could fit a scanline of */
   /* data at once into the BLT buffers (using both BB0 and BB1).  This */
   /* code is more generic to allow for any size BLT buffer. */

   if (dstx > srcx) {
      srcx += width;
      dstx += width;
   }

   /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS */
   /* Write the registers that do not change for each section. */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_HEIGHT, height);

   /* CHECK AVAILABLE BLT BUFFER SIZE */
   /* Can use both BLT buffers if no destination data is required. */

   buffer_width = GFXusesDstData ? GFXbufferWidthPixels :
	 GFXbufferWidthPixels << 1;

   /* REPEAT UNTIL FINISHED WITH RECTANGLE */
   /* Perform BLT in vertical sections, as wide as the BLT buffer allows. */
   /* Hardware does not split the operations, so software must do it to */
   /* avoid large scanlines that would overflow the BLT buffers. */

   while (width > 0) {
      /* CHECK WIDTH OF CURRENT SECTION */

      if (width > buffer_width)
	 section = buffer_width;
      else
	 section = width;

      /* PROGRAM REGISTERS THAT ARE THE SAME FOR EITHER X DIRECTION */

      GFX_WAIT_PENDING;
      WRITE_REG16(GP_SRC_YCOOR, srcy);
      WRITE_REG16(GP_DST_YCOOR, dsty);
      WRITE_REG16(GP_WIDTH, section);

      /* CHECK X DIRECTION */

      if (dstx > srcx) {
	 /* NEGATIVE X DIRECTION */
	 /* Still positive X direction within the section. */

	 srcx -= section;
	 dstx -= section;
	 WRITE_REG16(GP_SRC_XCOOR, srcx);
	 WRITE_REG16(GP_DST_XCOOR, dstx);
	 WRITE_REG16(GP_BLIT_MODE, blit_mode);
      } else {
	 /* POSITIVE X DIRECTION */

	 WRITE_REG16(GP_SRC_XCOOR, srcx);
	 WRITE_REG16(GP_DST_XCOOR, dstx);
	 WRITE_REG16(GP_BLIT_MODE, blit_mode);
	 dstx += section;
	 srcx += section;
      }
      width -= section;
   }
}

/*
//----------------------------------------------------------------------------
// SCREEN TO SCREEN TRANSPARENT BLT
//
// This routine should be used to perform a screen to screen BLT when a 
// specified color should by transparent.  The only supported ROP is SRCCOPY.
//
//      SRCX            screen X position to copy from
//      SRCY            screen Y position to copy from
//      DSTX            screen X position to copy to
//      DSTY            screen Y position to copy to
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//      COLOR           transparent color
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_screen_to_screen_xblt(unsigned short srcx, unsigned short srcy,
			  unsigned short dstx, unsigned short dsty,
			  unsigned short width, unsigned short height,
			  unsigned long color)
#else
void
gfx_screen_to_screen_xblt(unsigned short srcx, unsigned short srcy,
			  unsigned short dstx, unsigned short dsty,
			  unsigned short width, unsigned short height,
			  unsigned long color)
#endif
{
   unsigned short section, buffer_width;
   unsigned short blit_mode = BM_READ_SRC_FB;

   /* CHECK Y DIRECTION */
   /* Hardware has support for negative Y direction. */

   if (dsty > srcy) {
      blit_mode |= BM_REVERSE_Y;
      srcy += height - 1;
      dsty += height - 1;
   }

   /* CHECK X DIRECTION */
   /* Hardware does not support negative X direction since at the time */
   /* of development all supported resolutions could fit a scanline of */
   /* data at once into the BLT buffers (using both BB0 and BB1).  This */
   /* code is more generic to allow for any size BLT buffer. */

   if (dstx > srcx) {
      srcx += width;
      dstx += width;
   }

   /* CALCULATE BLT BUFFER SIZE */
   /* Need to use BB1 to store the BLT buffer data. */

   buffer_width = GFXbufferWidthPixels;

   /* WRITE TRANSPARENCY COLOR TO BLT BUFFER 1 */

   if (GFXbpp == 8) {
      color &= 0x00FF;
      color |= (color << 8);
   }
   color = (color & 0x0000FFFF) | (color << 16);

   /* WAIT UNTIL PIPELINE IS NOT BUSY BEFORE LOADING DATA INTO BB1 */
   /* Need to make sure any previous BLT using BB1 is complete. */
   /* Only need to load 32 bits of BB1 for the 1 pixel BLT that follows. */

   GFX_WAIT_BUSY;
   WRITE_SCRATCH32(GFXbb1Base, color);

   /* DO BOGUS BLT TO LATCH DATA FROM BB1 */
   /* Already know graphics pipeline is idle. */
   /* Only need to latch data into the holding registers for the current */
   /* data from BB1.  A 1 pixel wide BLT will suffice. */

   WRITE_REG32(GP_DST_XCOOR, 0);
   WRITE_REG32(GP_SRC_XCOOR, 0);
   WRITE_REG32(GP_WIDTH, 0x00010001);
   WRITE_REG16(GP_RASTER_MODE, 0x00CC);
   WRITE_REG16(GP_BLIT_MODE, BM_READ_SRC_FB | BM_READ_DST_BB1);

   /* WRITE REGISTERS FOR REAL SCREEN TO SCREEN BLT */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_HEIGHT, height);
   WRITE_REG16(GP_RASTER_MODE, 0x10C6);
   WRITE_REG32(GP_PAT_COLOR_0, 0xFFFFFFFF);

   /* REPEAT UNTIL FINISHED WITH RECTANGLE */
   /* Perform BLT in vertical sections, as wide as the BLT buffer allows. */
   /* Hardware does not split the operations, so software must do it to */
   /* avoid large scanlines that would overflow the BLT buffers. */

   while (width > 0) {
      /* CHECK WIDTH OF CURRENT SECTION */

      if (width > buffer_width)
	 section = buffer_width;
      else
	 section = width;

      /* PROGRAM REGISTERS THAT ARE THE SAME FOR EITHER X DIRECTION */

      GFX_WAIT_PENDING;
      WRITE_REG16(GP_SRC_YCOOR, srcy);
      WRITE_REG16(GP_DST_YCOOR, dsty);
      WRITE_REG16(GP_WIDTH, section);

      /* CHECK X DIRECTION */
      /* Again, this must be done in software, and can be removed if the */
      /* display driver knows that the BLT buffers will always be large  */
      /* enough to contain an entire scanline of a screen to screen BLT. */

      if (dstx > srcx) {
	 /* NEGATIVE X DIRECTION */
	 /* Still positive X direction within the section. */

	 srcx -= section;
	 dstx -= section;
	 WRITE_REG16(GP_SRC_XCOOR, srcx);
	 WRITE_REG16(GP_DST_XCOOR, dstx);
	 WRITE_REG16(GP_BLIT_MODE, blit_mode);
      } else {
	 /* POSITIVE X DIRECTION */

	 WRITE_REG16(GP_SRC_XCOOR, srcx);
	 WRITE_REG16(GP_DST_XCOOR, dstx);
	 WRITE_REG16(GP_BLIT_MODE, blit_mode);
	 dstx += section;
	 srcx += section;
      }
      width -= section;
   }
}

/*
//----------------------------------------------------------------------------
// COLOR BITMAP TO SCREEN BLT
//
// This routine transfers color bitmap data to the screen.  For most cases,
// when the ROP is SRCCOPY, it may be faster to write a separate routine that
// copies the data to the frame buffer directly.  This routine should be 
// used when the ROP requires destination data.
//
// Transparency is handled by another routine.
//
//      SRCX            X offset within source bitmap
//      SRCY            Y offset within source bitmap
//      DSTX            screen X position to render data
//      DSTY            screen Y position to render data
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//      *DATA           pointer to bitmap data
//      PITCH           pitch of bitmap data (bytes between scanlines)
//----------------------------------------------------------------------------
*/

#if GFX_2DACCEL_DYNAMIC
void
gu1_color_bitmap_to_screen_blt(unsigned short srcx, unsigned short srcy,
			       unsigned short dstx, unsigned short dsty,
			       unsigned short width, unsigned short height,
			       unsigned char *data, long pitch)
#else
void
gfx_color_bitmap_to_screen_blt(unsigned short srcx, unsigned short srcy,
			       unsigned short dstx, unsigned short dsty,
			       unsigned short width, unsigned short height,
			       unsigned char *data, long pitch)
#endif
{
   unsigned short section, buffer_width;
   unsigned short blit_mode = BM_READ_SRC_BB0;
   unsigned short temp_height;
   unsigned long dword_bytes_needed, bytes_extra;
   unsigned long bpp_shift;
   long array_offset;

   /* CHECK SIZE OF BLT BUFFER */

   buffer_width = GFXbufferWidthPixels;

   /* CHECK IF RASTER OPERATION REQUIRES DESTINATION DATA */
   /* If no destination data, we have twice the room for  */
   /* source data.                                        */

   if (GFXusesDstData)
      blit_mode |= BM_READ_DST_FB1;
   else
      buffer_width <<= 1;

   /* SET THE SCRATCHPAD BASE */

   SET_SCRATCH_BASE(GFXbb0Base);

   /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS                */
   /* Write the registers that do not change for each section. */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_HEIGHT, 1);

   bpp_shift = (GFXbpp + 7) >> 4;

   while (width > 0) {
      if (width > buffer_width)
	 section = buffer_width;
      else
	 section = width;

      dword_bytes_needed = (section << bpp_shift) & ~3l;
      bytes_extra = (section << bpp_shift) & 3l;

      temp_height = height;

      /* WRITE THE REGISTERS FOR EACH SECTION                          */
      /* The GX hardware will auto-increment the Y coordinate, meaning */
      /* that we don't have to.                                        */

      WRITE_REG16(GP_WIDTH, section);
      WRITE_REG16(GP_DST_XCOOR, dstx);
      WRITE_REG16(GP_DST_YCOOR, dsty);

      /* CALCULATE THE BITMAP OFFSET */

      array_offset =
	    (unsigned long)srcy *(long)pitch + ((long)srcx << bpp_shift);

      while (temp_height--) {
	 GFX_WAIT_PIPELINE;

	 /* WRITE ALL DATA TO THE BLT BUFFERS */
	 /* The WRITE_SCRATCH_STRING macro assumes that the data begins at the */
	 /* scratchpad offset set by the SET_SCRATCH_BASE macro.               */

	 WRITE_SCRATCH_STRING(dword_bytes_needed, bytes_extra, data,
			      array_offset);
	 WRITE_REG16(GP_BLIT_MODE, blit_mode);

	 array_offset += pitch;
      }

      width -= section;
      srcx += section;
      dstx += section;
   }
}

/*
//----------------------------------------------------------------------------
// COLOR BITMAP TO SCREEN TRANSPARENT BLT
//
// This routine transfers color bitmap data to the screen with transparency.
// The transparent color is specified.  The only supported ROP is SRCCOPY, 
// meaning that transparency cannot be applied if the ROP requires 
// destination data (this is a hardware restriction).
//
//      SRCX            X offset within source bitmap
//      SRCY            Y offset within source bitmap
//      DSTX            screen X position to render data
//      DSTY            screen Y position to render data
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//      *DATA           pointer to bitmap data
//      PITCH           pitch of bitmap data (bytes between scanlines)
//      COLOR           transparent color
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_color_bitmap_to_screen_xblt(unsigned short srcx, unsigned short srcy,
				unsigned short dstx, unsigned short dsty,
				unsigned short width, unsigned short height,
				unsigned char *data, long pitch,
				unsigned long color)
#else
void
gfx_color_bitmap_to_screen_xblt(unsigned short srcx, unsigned short srcy,
				unsigned short dstx, unsigned short dsty,
				unsigned short width, unsigned short height,
				unsigned char *data, long pitch,
				unsigned long color)
#endif
{
   unsigned short section, buffer_width;
   unsigned short temp_height;
   unsigned long dword_bytes_needed, bytes_extra;
   unsigned long bpp_shift;
   long array_offset;

   /* CHECK SIZE OF BLT BUFFER */

   buffer_width = GFXbufferWidthPixels;

   /* WRITE TRANSPARENCY COLOR TO BLT BUFFER 1 */

   if (GFXbpp == 8) {
      color &= 0x00FF;
      color |= (color << 8);
   }
   color = (color & 0x0000FFFF) | (color << 16);

   /* WAIT UNTIL PIPELINE IS NOT BUSY BEFORE LOADING DATA INTO BB1 */
   /* Need to make sure any previous BLT using BB1 is complete. */
   /* Only need to load 32 bits of BB1 for the 1 pixel BLT that follows. */

   GFX_WAIT_PIPELINE;
   GFX_WAIT_PENDING;
   WRITE_SCRATCH32(GFXbb1Base, color);

   /* DO BOGUS BLT TO LATCH DATA FROM BB1 */
   /* Already know graphics pipeline is idle. */
   /* Only need to latch data into the holding registers for the current */
   /* data from BB1.  A 1 pixel wide BLT will suffice. */

   WRITE_REG32(GP_DST_XCOOR, 0);
   WRITE_REG32(GP_SRC_XCOOR, 0);
   WRITE_REG32(GP_WIDTH, 0x00010001);
   WRITE_REG16(GP_RASTER_MODE, 0x00CC);
   WRITE_REG16(GP_BLIT_MODE, BM_READ_SRC_FB | BM_READ_DST_BB1);

   /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS */
   /* Write the registers that do not change for each section. */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_HEIGHT, 1);
   WRITE_REG16(GP_RASTER_MODE, 0x10C6);
   WRITE_REG32(GP_PAT_COLOR_0, 0xFFFFFFFF);

   bpp_shift = (GFXbpp + 7) >> 4;

   /* SET THE SCRATCHPAD BASE */

   SET_SCRATCH_BASE(GFXbb0Base);

   while (width > 0) {
      if (width > buffer_width)
	 section = buffer_width;
      else
	 section = width;

      dword_bytes_needed = (section << bpp_shift) & ~3l;
      bytes_extra = (section << bpp_shift) & 3l;

      temp_height = height;

      /* WRITE THE REGISTERS FOR EACH SECTION                          */
      /* The GX hardware will auto-increment the Y coordinate, meaning */
      /* that we don't have to.                                        */

      WRITE_REG16(GP_WIDTH, section);
      WRITE_REG16(GP_DST_XCOOR, dstx);
      WRITE_REG16(GP_DST_YCOOR, dsty);

      /* CALCULATE THE BITMAP OFFSET */

      array_offset =
	    (unsigned long)srcy *(long)pitch + ((long)srcx << bpp_shift);

      while (temp_height--) {
	 GFX_WAIT_PIPELINE;

	 /* WRITE ALL DATA TO THE BLT BUFFERS */
	 /* The WRITE_SCRATCH_STRING macro assumes that the data begins at the */
	 /* scratchpad offset set by the SET_SCRATCH_BASE macro.               */

	 WRITE_SCRATCH_STRING(dword_bytes_needed, bytes_extra, data,
			      array_offset);
	 WRITE_REG16(GP_BLIT_MODE, BM_READ_SRC_BB0);

	 array_offset += pitch;
      }

      width -= section;
      srcx += section;
      dstx += section;
   }
}

/*
//----------------------------------------------------------------------------
// MONOCHROME BITMAP TO SCREEN BLT
//
// This routine transfers monochrome bitmap data to the screen.  
//
//      SRCX            X offset within source bitmap
//      SRCY            Y offset within source bitmap
//      DSTX            screen X position to render data
//      DSTY            screen Y position to render data
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//      *DATA           pointer to bitmap data
//      PITCH           pitch of bitmap data (bytes between scanlines)
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_mono_bitmap_to_screen_blt(unsigned short srcx, unsigned short srcy,
			      unsigned short dstx, unsigned short dsty,
			      unsigned short width, unsigned short height,
			      unsigned char *data, short pitch)
#else
void
gfx_mono_bitmap_to_screen_blt(unsigned short srcx, unsigned short srcy,
			      unsigned short dstx, unsigned short dsty,
			      unsigned short width, unsigned short height,
			      unsigned char *data, short pitch)
#endif
{
   unsigned short section, buffer_width;
   unsigned short blit_mode = BM_READ_SRC_BB0 | BM_SOURCE_EXPAND;
   unsigned short temp_height;
   unsigned long dword_bytes_needed, bytes_extra;
   long array_offset;

   /* CHECK IF RASTER OPERATION REQUIRES DESTINATION DATA        */
   /* If no destination data, the source data will always fit.   */
   /* So, in that event we will set the buffer width to a        */
   /* fictitiously large value such that the BLT is never split. */

   if (GFXusesDstData) {
      buffer_width = GFXbufferWidthPixels;
      blit_mode |= BM_READ_DST_FB1;
   } else
      buffer_width = 3200;

   /* CHECK IF DATA ALREADY IN BLIT BUFFER */
   /* If the pointer is NULL, data for the full BLT is already there */
   /* WARNING: This could cause problems if destination data is */
   /* involved and it overflows the BLT buffer.  Need to remove */
   /* this option and change the drivers to use a temporary buffer. */

   if (!data) {
      GFX_WAIT_PENDING;
      WRITE_REG16(GP_SRC_XCOOR, srcx & 7);
      WRITE_REG16(GP_DST_XCOOR, dstx);
      WRITE_REG16(GP_DST_YCOOR, dsty);
      WRITE_REG16(GP_WIDTH, width);
      WRITE_REG16(GP_HEIGHT, height);
      WRITE_REG16(GP_BLIT_MODE, blit_mode);
      return;
   }

   /* SET THE SCRATCHPAD BASE */

   SET_SCRATCH_BASE(GFXbb0Base);

   /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS */
   /* Write the registers that do not change for each section. */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_HEIGHT, 1);

   while (width > 0) {
      if (width > buffer_width)
	 section = buffer_width;
      else
	 section = width;

      /* CALCULATE BYTES NEEDED */
      /* Add 1 for possible alignment issues. */

      dword_bytes_needed = ((section + 7 + (srcx & 7)) >> 3) & ~3l;
      bytes_extra = ((section + 7 + (srcx & 7)) >> 3) & 3l;

      temp_height = height;

      /* WRITE THE REGISTERS FOR EACH SECTION                          */
      /* The GX hardware will auto-increment the Y coordinate, meaning */
      /* that we don't have to.                                        */

      WRITE_REG16(GP_WIDTH, section);
      WRITE_REG16(GP_DST_XCOOR, dstx);
      WRITE_REG16(GP_DST_YCOOR, dsty);
      WRITE_REG16(GP_SRC_XCOOR, srcx & 7);

      /* CALCULATE THE BITMAP OFFSET */

      array_offset = (unsigned long)srcy *(long)pitch + ((long)srcx >> 3);

      while (temp_height--) {
	 GFX_WAIT_PIPELINE;

	 /* WRITE ALL DATA TO THE BLT BUFFERS */
	 /* The WRITE_SCRATCH_STRING macro assumes that the data begins at the */
	 /* scratchpad offset set by the SET_SCRATCH_BASE macro.               */

	 WRITE_SCRATCH_STRING(dword_bytes_needed, bytes_extra, data,
			      array_offset);
	 WRITE_REG16(GP_BLIT_MODE, blit_mode);

	 array_offset += pitch;
      }

      width -= section;
      srcx += section;
      dstx += section;
   }
}

/*
//----------------------------------------------------------------------------
// MONOCHROME TEXT BLT
//
// This routine transfers contiguous monochrome text data to the screen.  
//
//      DSTX            screen X position to render data
//      DSTY            screen Y position to render data
//      WIDTH           width of rectangle, in pixels
//      HEIGHT          height of rectangle, in scanlines
//      *DATA           pointer to bitmap data
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_text_blt(unsigned short dstx, unsigned short dsty, unsigned short width,
	     unsigned short height, unsigned char *data)
#else
void
gfx_text_blt(unsigned short dstx, unsigned short dsty, unsigned short width,
	     unsigned short height, unsigned char *data)
#endif
{
   unsigned long dword_bytes_needed, bytes_extra;
   long pitch, buffer_bytes, data_bytes;

   /* CALCULATE DATA SIZE */

   pitch = (width + 7) >> 3;
   data_bytes = (long)height *pitch;

   /* CHECK FOR SIMPLE CASE */
   /* This routine is designed to render a source copy text glyph.  If destination */
   /* data is required or the source data will not fit, we will punt the operation */
   /* to the more versatile (and slow) mono bitmap routine.                        */

   if (GFXbpp > 8)
      buffer_bytes = GFXbufferWidthPixels << 1;
   else
      buffer_bytes = GFXbufferWidthPixels;

   if (GFXusesDstData || data_bytes > buffer_bytes) {
      gfx_mono_bitmap_to_screen_blt(0, 0, dstx, dsty, width, height, data,
				    (short)pitch);
      return;
   }

   /* SET THE SCRATCHPAD BASE */

   SET_SCRATCH_BASE(GFXbb0Base);

   /* POLL UNTIL ABLE TO WRITE TO THE REGISTERS */

   dword_bytes_needed = data_bytes & ~3l;
   bytes_extra = data_bytes & 3l;

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_HEIGHT, height);
   WRITE_REG16(GP_WIDTH, width);
   WRITE_REG16(GP_DST_XCOOR, dstx);
   WRITE_REG16(GP_DST_YCOOR, dsty);
   WRITE_REG16(GP_SRC_XCOOR, 0);

   /* WRITE ALL DATA TO THE BLT BUFFERS */
   /* The WRITE_SCRATCH_STRING macro assumes that the data begins at the */
   /* scratchpad offset set by the SET_SCRATCH_BASE macro.               */

   GFX_WAIT_PIPELINE;

   WRITE_SCRATCH_STRING(dword_bytes_needed, bytes_extra, data, 0);
   WRITE_REG16(GP_BLIT_MODE, BM_READ_SRC_BB0 | BM_SOURCE_TEXT);
}

/*
//----------------------------------------------------------------------------
// BRESENHAM LINE
//
// This routine draws a vector using the specified Bresenham parameters.  
// Currently this file does not support a routine that accepts the two 
// endpoints of a vector and calculates the Bresenham parameters.  If it 
// ever does, this routine is still required for vectors that have been 
// clipped.
//
//      X               screen X position to start vector
//      Y               screen Y position to start vector
//      LENGTH          length of the vector, in pixels
//      INITERR         Bresenham initial error term
//      AXIALERR        Bresenham axial error term
//      DIAGERR         Bresenham diagonal error term
//      FLAGS           VM_YMAJOR, VM_MAJOR_INC, VM_MINOR_INC
//----------------------------------------------------------------------------
*/
#if GFX_2DACCEL_DYNAMIC
void
gu1_bresenham_line(unsigned short x, unsigned short y,
		   unsigned short length, unsigned short initerr,
		   unsigned short axialerr, unsigned short diagerr,
		   unsigned short flags)
#else
void
gfx_bresenham_line(unsigned short x, unsigned short y,
		   unsigned short length, unsigned short initerr,
		   unsigned short axialerr, unsigned short diagerr,
		   unsigned short flags)
#endif
{
   unsigned short vector_mode = flags;

   if (GFXusesDstData)
      vector_mode |= VM_READ_DST_FB;

   /* CHECK NULL LENGTH */

   if (!length)
      return;

   /* LOAD THE REGISTERS FOR THE VECTOR */

   GFX_WAIT_PENDING;
   WRITE_REG16(GP_DST_XCOOR, x);
   WRITE_REG16(GP_DST_YCOOR, y);
   WRITE_REG16(GP_VECTOR_LENGTH, length);
   WRITE_REG16(GP_INIT_ERROR, initerr);
   WRITE_REG16(GP_AXIAL_ERROR, axialerr);
   WRITE_REG16(GP_DIAG_ERROR, diagerr);
   WRITE_REG16(GP_VECTOR_MODE, vector_mode);
}

/*---------------------------------------------------------------------------
 * GFX_WAIT_UNTIL_IDLE
 *
 * This routine waits until the graphics engine is idle.  This is required
 * before allowing direct access to the frame buffer.
 *---------------------------------------------------------------------------
 */
#if GFX_2DACCEL_DYNAMIC
void
gu1_wait_until_idle(void)
#else
void
gfx_wait_until_idle(void)
#endif
{
   GFX_WAIT_BUSY;
}

/*---------------------------------------------------------------------------
 * GFX_TEST_BLT_PENDING
 *
 * This routine returns 1 if a BLT is pending, meaning that a call to 
 * perform a rendering operation would stall.  Otherwise it returns 0.
 * It is used by Darwin during random testing to only start a BLT 
 * operation when it knows the Durango routines won't spin on graphics
 * (so Darwin can continue to do frame buffer reads and writes).
 *---------------------------------------------------------------------------
 */
#if GFX_2DACCEL_DYNAMIC
int
gu1_test_blt_pending(void)
#else
int
gfx_test_blt_pending(void)
#endif
{
   if (READ_REG16(GP_BLIT_STATUS) & BS_BLIT_PENDING)
      return (1);
   else
      return (0);
}

/*---------------------------------------------------------------------------
 * BLT BUFFERS!!!!!
 *---------------------------------------------------------------------------
 */

/* THE BOOT CODE MUST SET THE BLT BUFFER BASES USING THE "CPU_WRITE" */
/* INSTRUCTION TO ONE OF THE FOLLOWING VALUES: */

#define BB0_BASE_2K		0x800
#define BB1_BASE_2K		0xB30
#define BB0_BASE_3K		0x400
#define BB1_BASE_3K		0x930

/*---------------------------------------------------------------------------
 * gu1_detect_blt_buffer_base
 * 
 * This detection is hidden from the driver by being called from the 
 * "gfx_set_bpp" routine.  
 *
 * This is fairly ugly for the following reasons:
 *
 * - It is the boot code that must set the BLT buffer bases to the 
 *   appropriate values and load the scratchpad tags.  
 * - The old drivers would also set the base address values to what they
 *   knew they should be for the 2K or 3K scratchpad configuration.
 * - Unfortunately, to set the base addresses requires the use of the 
 *   CPU_WRITE instruction, an instruction specific to GX.
 * - Using the CPU_WRITE instruction requires the use of assembly to 
 *   produce the appropriate op codes.
 * - Assembly is something that is avoided in Durango because it is not
 *   platform independent.  Some compilers do not support inline assembly.
 * - Therefore Durango cannot use the CPU_WRITE instruction.
 * - Therefore drivers using Durango must rely on the boot code to set
 *   the appropriate values.  Durango uses this routine to check where
 *   the base addresses have been set.
 * - Unfortunately, it is not as simple as using IO to check for 2K or 3K 
 *   scratchpad size.  In VSA1, even though the boot code may set it for
 *   3K, SoftVGA comes along and resets it to 2K for it's use in text
 *   redraws.  It used to be that the display driver would set it back
 *   to 3K.  
 * - So, the Durango code was changed to just always use 2K.
 * - But, the XpressROM code sets it for 3K, and the newer versions of 
 *   SoftVGA do not interfere with that, so then Durango needs to use
 *   the 3K values to work properly.
 * - Therefore, Durango does somewhat of a kludge by writing to directly
 *   to the scratchpad at both the 2K and 3K locations, then performing
 *   a unobtrusive BLT that loads data into BB0 (the graphics engine 
 *   always knows the true base).  After the BLT, Durango looks to see
 *   which location changed to know where the base address is.
 * - This is a relatively simple way to allow Durango to work on old
 *   and new platforms without using theCPU_WRITE instructions.
 *
 * To summarize, the BLT buffers are one of the most painful aspects of 
 * the GX graphics unit design, and have been removed from future designs
 * (the graphics unit has its own dedicated RAM).  Durango has tried to 
 * hide the BLT buffer use from the drivers.
 *---------------------------------------------------------------------------
 */
void
gu1_detect_blt_buffer_base(void)
{
   /* ASSUME 2K */

   GFXbb0Base = BB0_BASE_2K;
   GFXbb1Base = BB1_BASE_2K;

   /* CHECK IF SCRATCHPAD IS SET TO 3K OR 4K */
   /* Boot code should still set 3K values for 4K. */

   if (gfx_gxm_config_read(GXM_CONFIG_GCR) & 0x08) {
      /* WRITE DATA TO 3K LOCATION */

      GFX_WAIT_BUSY;
      WRITE_SCRATCH32(BB0_BASE_3K, 0xFEEDFACE);

      /* HAVE THE GRAPHICS UNIT STORE SOMETHING IN BB0 */

      WRITE_REG32(GP_DST_XCOOR, 0x00000000);	/* AT (0,0) */
      WRITE_REG32(GP_WIDTH, 0x00010004);	/* 4x1 BLT */
      WRITE_REG16(GP_RASTER_MODE, 0x00AA);	/* KEEP DST */
      WRITE_REG16(GP_BLIT_MODE, BM_READ_DST_FB0);	/* STORE IN BB0 */

      /* CHECK 3K LOCATION */
      /* Breaks if data happened to be 0xFEEDFACE - unlikely. */

      GFX_WAIT_BUSY;
      if (READ_SCRATCH32(BB0_BASE_3K) != 0xFEEDFACE) {
	 GFXbb0Base = BB0_BASE_3K;
	 GFXbb1Base = BB1_BASE_3K;
      }
   }
}

/* END OF FILE */