vga_routines.c

VGA模块的VHDL代码和软件驱动

#include "vga_routines.h"
#include "vga_regs.h"
#include <sys/alt_cache.h>

int vga_init( void* vga_base )
{
	IOWR_VGACARD_CTRL( vga_base, 0 );
	if( ( IORD_VGACARD_CTRL( vga_base ) & IORD_VGACARD_CTRL_MASK ) != VGACARD_INIT_STATE )
		{
		return -1;
		}//end if
	return 0;
}//end vga_init

int vga_set_display( void* vga_base, int displ_en )
{
	int displ_bit = (displ_en) ? VGACARD_DISP_EN_BIT : 0;
	IOWR_VGACARD_CTRL( vga_base, displ_bit );
	if( ( IORD_VGACARD_CTRL( vga_base ) & VGACARD_DISP_EN_BIT ) != displ_bit )
		{
		return -1;
		}//end if
	return 0;
}//end vga_set_display

static void dma_done( void* done, void* data )
{	
	*((int*)done) = 1;
}//end dma_done;

int vga_write_memory( alt_dma_txchan tx, alt_dma_rxchan rx, void* vga_addr, const alt_u16* data, int cnt, int* done, int wait )
{
	int i, j;
	int size;
	int res = -1;
	
	if( tx == NULL || rx == NULL )
		{
		for( i = j = 0; i < cnt; ++i, j += 2 )
			{
			IOWR_VGACARD_DATA( vga_addr + j, data[i] );
			}//end for
		res = 0;
		}
	else{
		size = cnt << 1;
		*done = 0;
		alt_dcache_flush( (void*)data, size );
		res = alt_dma_txchan_send( tx, data, size, NULL, NULL );
		if( res == 0 )
			{
			res = alt_dma_rxchan_prepare( rx, vga_addr, size, dma_done, (void*)&done );
			}//end if
		
		if( res == 0 && wait )
			{
			while( !(*done) );
			}//end if
		}//end if
	
	return res;
}//end vga_write_memory

int vga_read_memory( void* vga_addr, alt_u16* data, int cnt )
{
	int i, j;
	
	for( i = j = 0; i < cnt; ++i, j += 2 )
		{
		data[i] = IORD_VGACARD_DATA( vga_addr + j );
		}//end for
	
	return 0;
}//end vga_write_memory

int vga_switch( void* vga_base )
{
	IOWR_VGACARD_CTRL( vga_base, VGACARD_DISP_EN_BIT | VGACARD_SWITCH_BIT );
	return 0;
}//end vga_switch