//-------------------------------------------------------------------
//	sisaccel.cpp
//
//	This demo illustrates two capabilities of the SiS 315 GPU's 
//	2D graphics engine: drawing rectangles and linear segments.
//	(Other manufacturers of SVGA hardware provide such features
//	using programming interfaces which are roughly similar, but 
//	different in their implementation details.) 
//
//	Some supporting software is needed to run this demo:
//	   (1) our Linux device-driver module 'vram.c'
//	   (2) our Linux device-driver module 'engine2d.c'
//	   (3) our 'sisaccel.h' header (from cs686 website)
//	   (4) the 'mode3' utility from the SVGALIB package
//	
//	programmer: ALLAN CRUSE
//	date begun: 02 NOV 2003
//	completion: 03 NOV 2003
//-------------------------------------------------------------------

#include <stdio.h>	// for printf(), perror() 
#include <fcntl.h>	// for open() 
#include <stdlib.h>	// for exit() 
#include <unistd.h>	// for read(), write(), close() 
#include <termios.h>	// for tcgetattr(), tcsetattr() 
#include <sys/mman.h>	// for mmap() 
#include <sys/io.h>	// for iopl() 
#include "sisaccel.h"	// for map_engine_memory()

#define VRAM_BASE_ADDRESS 0xA0000000 
#define VGA_MEMORY_LENGTH ( 4 << 20) 
#define SIS315_CMD_BITBLT    0x00
#define SIS315_CMD_LINE_DRAW 0x04
#define ROP_COPY_SRC_PAT     0xF0
#define SIS315_CTL_CFB_32 0x00020000

unsigned long *vram = (unsigned long*)VRAM_BASE_ADDRESS; 
const int display_mode = 0x413B, hres = 800, vres = 600; 

void enable_graphics_engine( void );
void rectangle( int x, int y, int h, int v, int color, u8 rop );
void line(int x0, int y0, int x1, int y1, int c0, int c1, u8 rop);

void draw_rectangle( int x, int y, int h, int v, int color ) 
{
	int	minx = x, miny = y, maxx = h-1, maxy = v-1; 

	do { vram[ y*hres + x ] = color; ++x; } while ( x < maxx ); 
	do { vram[ y*hres + x ] = color; ++y; } while ( y < maxy ); 
	do { vram[ y*hres + x ] = color; --x; } while ( x > minx ); 
	do { vram[ y*hres + x ] = color; --y; } while ( y > miny ); 
}




int main( int argc, char **argv )
{
	if ( iopl( 3 ) ) { perror( "iopl" ); exit(1); }

	system( "/sbin/insmod engine2d.o" ); 
	map_engine_memory( MMIO_BASE_ADDRESS, MMIO_MEMORY_RANGE ); 

	system( "/sbin/insmod vram.o" ); 
	map_screen_memory( VRAM_BASE_ADDRESS, VGA_MEMORY_LENGTH ); 

	struct termios	otty; 
	tcgetattr( 0, &otty ); 
	struct termios	tty = otty; 
	tty.c_lflag &= ~( ICANON | ECHO | ISIG ); 
	tty.c_cc[ VMIN ] = 1; 
	tty.c_cc[ VTIME ] = 0; 
	tcsetattr( 0, TCSAFLUSH, &tty ); 

	char	command[ 40 ]; 
	sprintf( command, " clear ; mode3 %d ", display_mode ); 
	system( command ); 

	int	white = 0xFFFFFF, purple = 0xFF00FF, rop = 0xF0;
	int	red = 0xFF0000, green = 0x00FF00, blue = 0x0000FF;
	draw_rectangle( 0, 0, hres, vres, white ); 
	getchar(); 

	enable_graphics_engine();
	draw_rectangle( 2, 2, hres-2, vres-2, white );
	getchar();

	rectangle( hres/4, vres/4, hres/2, vres/2, red, rop );  
	getchar();
	rectangle( 170, 130, 320, 240, purple, rop );  
	getchar();

	line( hres/4, vres/4, 3*hres/4, 3*vres/4, blue, green, rop );
	getchar();

	system( " mode3 3 " ); 
	tcsetattr( 0, TCSAFLUSH, &otty ); 
}

void enable_graphics_engine( void )
{
	outw( 0x8605, TSEQ );	// unlock SiS registers
	outw( 0xA120, TSEQ );	// enable memory-map io
	outw( 0x401E, TSEQ );	// enable SiS 2D-engine
	outw( 0xAE08, TSEQ );	// ?? 
	outw( 0x060C, TSEQ );	// ?? 
	outw( 0x0F11, TSEQ );	// disables power-management mode
	outw( 0x1F27, TSEQ );	// set max cmd-queue threshhold
	outw( 0x0126, TSEQ );	// synchronous reset
	*cmd_queue_wr = *cmd_queue_rd;
	outw( 0x2226, TSEQ );	// enable command-queue and mmio

	// set the command-queue base-address
	u32	tqueue_size = (512 << 10);	// 512K
	u32	tqueue_base = ( 32 << 20);	// 32MB
	tqueue_base -= tqueue_size;
	*queue_origin = tqueue_base;	

	// wait until the command queue is idle
	int	counter = 16;
	volatile u32	dummy = 0;
	while (( dummy != 0x80000000 )&&( --counter > 0 )) 
		{ dummy = *queue_status; dummy &= 0x80000000; }
}




void rectangle( int x, int y, int h, int v, int color, u8 rop )
{
	*agp_baseword = 0xC000;
	
	*src_pitchval = hres*4;
	*dst_pitchval = hres*4;

	*mergecontrol = ~0;

	*src_baseaddr = 0;
	*dst_baseaddr = 0;

	*src_origin_x = 0;
	*src_origin_y = 0;

	*dst_origin_x = x;
	*dst_origin_y = y;
	
	*rect_size_hz = h;
	*rect_size_vt = v;

	*pat_fg_color = color;

	*monomask_reg = ~0LL;	// ???

		*clip_lft_reg = 0;
		*clip_top_reg = 0;
		*clip_rht_reg = ~0;
		*clip_bot_reg = ~0;

	u32 	command = SIS315_CMD_BITBLT;
	command |= ( (u32)rop << 8 );
	command |= SIS315_CTL_CFB_32;

	*exec_command = command;
	*exec_command = command;
}




void line( int x0, int y0, int x1, int y1, int c0, int c1, u8 rop )
{
	*agp_baseword = 0xC000;
	
	*src_pitchval = hres*4;
	*dst_pitchval = hres*4;

	*mergecontrol = ~0;

	*src_baseaddr = 0;
	*dst_baseaddr = 0;

	*line_x0 = x0;
	*line_y0 = y0;
	
	*line_x1 = x1;
	*line_y1 = y1;

	*line_style_0 = ~0;
	*line_style_1 = ~0;

	*pat_fg_color = c0;
	*pat_bg_color = c1;
	*src_fg_color = c0;
	*src_fg_color = c1;

	*line_count = 1;
	*line_style_period = 0;

	*monomask_reg = ~0LL;	// ???

		*clip_lft_reg = 0;
		*clip_top_reg = 0;
		*clip_rht_reg = ~0;
		*clip_bot_reg = ~0;

	u32 	command = SIS315_CMD_LINE_DRAW;
	command |= ( (u32)rop << 8 );
	command |= SIS315_CTL_CFB_32;

	*exec_command = command;
	*exec_command = command;
}