vesa.c

linux 下svgalib编的一个界面程序示例

/*
*/


#include <stdlib.h>
#include <stdio.h>		/* for printf */
#include <string.h>		/* for memset */
#include <unistd.h>
#include <sys/mman.h>		/* for mmap */
#include "vga.h"
#include "libvga.h"
#include "driver.h"


/* New style driver interface. */
#include "timing.h"
#include "vgaregs.h"
#include "interface.h"
#include "accel.h"
#include "lrmi.h"
#include "vbe.h"
#define VESAREG_SAVE(i) (VGA_TOTAL_REGS+i)
#define VESA_TOTAL_REGS (VGA_TOTAL_REGS + 4024)

/* #define VESA_savebitmap 0x0e */
int __svgalib_VESA_savebitmap=0x0e;
int __svgalib_VESA_textmode=3;

static int vesa_init(int, int, int);
static void vesa_unlock(void);

static int vesa_memory,vesa_chiptype;
static int vesa_is_linear, vesa_logical_width, vesa_bpp, vesa_granularity;
static int vesa_regs_size, vesa_linear_base, vesa_last_mode_set;
static struct LRMI_regs vesa_r;
static int vesa_read_write, vesa_read_window, vesa_write_window;
static void * LRMI_mem1;

static CardSpecs *cardspecs;
static struct
	{
	struct vbe_info_block *info;
	struct vbe_mode_info_block *mode;
	} vesa_data;

static int SVGALIB_VESA[__GLASTMODE+1];

static int lrmi_inited=0;

static void vesa_setpage(int page)
{
vesa_r.eax=0x4f05;
vesa_r.ebx=0;
vesa_r.edx=page*64/vesa_granularity;
__svgalib_LRMI_int(0x10,&vesa_r);

if(vesa_read_write){
   vesa_r.eax=0x4f05;
   vesa_r.ebx=1;
   vesa_r.edx=page*64/vesa_granularity;
   __svgalib_LRMI_int(0x10,&vesa_r);
};
}


static int __svgalib_vesa_inlinearmode(void)
{
return vesa_is_linear;
}


/* Fill in chipset specific mode information */

static void vesa_getmodeinfo(int mode, vga_modeinfo *modeinfo)
{
    if ((mode < G640x480x256 )
	|| mode == G720x348x2)
	return __svgalib_vga_driverspecs.getmodeinfo(mode, modeinfo);

    if(modeinfo->colors==16)return;

    modeinfo->maxpixels = vesa_memory*1024/modeinfo->bytesperpixel;
    modeinfo->maxlogicalwidth = 4088; /* just a guess, */
    modeinfo->startaddressrange = vesa_memory * 1024 - 1;
    modeinfo->haveblit = 0;
    modeinfo->flags &= ~HAVE_RWPAGE;
    modeinfo->flags |= vesa_read_write;  /* sets HAVE_RWPAGE bit */

    /* for linear need VBE2 */
    if(vesa_chiptype>=1)
      if (modeinfo->bytesperpixel >= 1) {
	modeinfo->flags |= CAPABLE_LINEAR;
        if (__svgalib_vesa_inlinearmode())
	    modeinfo->flags |= IS_LINEAR;
      }
      
    /* to get the logical scanline width */
    memset(&vesa_r, 0, sizeof(vesa_r));

    vesa_r.eax = 0x4f01;
    vesa_r.ecx = SVGALIB_VESA[mode];
    vesa_r.es = (unsigned int)vesa_data.mode >> 4;
    vesa_r.edi = (unsigned int)vesa_data.mode & 0xf;

    if (!__svgalib_LRMI_int(0x10, &vesa_r)) {
       fprintf(stderr, "Can't get mode info (vm86 failure)\n");
       return;
    }
    modeinfo->linewidth = vesa_data.mode->bytes_per_scanline;
}

/* Read and save chipset-specific registers */
static int vesa_saveregs(unsigned char regs[])
{ 
  void * buf;
  buf=LRMI_mem1;
  vesa_r.eax=0x4f04;
  vesa_r.ebx=0;
  vesa_r.es=((long)buf)>>4;
  vesa_r.edx=1;
  vesa_r.ecx=__svgalib_VESA_savebitmap;
  __svgalib_LRMI_int(0x10,&vesa_r);
  memcpy(&regs[VGA_TOTAL_REGS],buf,vesa_regs_size);  
    return vesa_regs_size;
}

/* Set chipset-specific registers */

static void vesa_setregs(const unsigned char regs[], int mode)
{   

  void * buf;
  buf=LRMI_mem1;
  memcpy(buf,&regs[VGA_TOTAL_REGS],vesa_regs_size);  
  vesa_r.eax=0x4f04;
  vesa_r.ebx=0;
  vesa_r.es=((long)buf)>>4;
  vesa_r.edx=2;
  vesa_r.ecx=__svgalib_VESA_savebitmap;
  __svgalib_LRMI_int(0x10,&vesa_r);
}


/* Return nonzero if mode is available */

static int vesa_modeavailable(int mode)
{
    struct info *info;
    ModeTiming *modetiming;
    ModeInfo *modeinfo;


    if ((mode < G640x480x256 )
	|| mode == G720x348x2)
	return __svgalib_vga_driverspecs.modeavailable(mode);

    info = &__svgalib_infotable[mode];

    modeinfo = __svgalib_createModeInfoStructureForSvgalibMode(mode);

    modetiming = malloc(sizeof(ModeTiming));
    if (__svgalib_getmodetiming(modetiming, modeinfo, cardspecs)) {
	free(modetiming);
	free(modeinfo);
	return 0;
    }
    free(modetiming);
    free(modeinfo);

return SVGALIB_VESA[mode];
}

static int vesa_setmode(int mode, int prv_mode)
{
    vesa_bpp=1;
    vesa_granularity=1;
    if ((mode < G640x480x256)|| (mode == G720x348x2)) {

        if(__svgalib_vesatext){
            vesa_r.eax=0x4f02; /* make sure we are in a regular VGA mode before we start */
            vesa_r.ebx=__svgalib_VESA_textmode;    /* without this, if we start in SVGA mode the result might */
            __svgalib_LRMI_int(0x10,&vesa_r); /* be something weird */
        };
	return __svgalib_vga_driverspecs.setmode(mode, prv_mode);
    }
    if (!vesa_modeavailable(mode)) return 1;
    vesa_r.eax=0x4f02;
    vesa_r.ebx=SVGALIB_VESA[mode]|0x8000|(vesa_is_linear*0x4000);
    vesa_last_mode_set=vesa_r.ebx;
    __svgalib_LRMI_int(0x10,&vesa_r);

    vesa_r.eax = 0x4f01;
    vesa_r.ecx=SVGALIB_VESA[mode];
    vesa_r.es = (unsigned int)vesa_data.mode >> 4;
    vesa_r.edi = (unsigned int)vesa_data.mode&0xf;    
    __svgalib_LRMI_int(0x10, &vesa_r);
    vesa_logical_width=vesa_data.mode->bytes_per_scanline;
    vesa_bpp=(vesa_data.mode->bits_per_pixel+7)/8;
    if(vesa_logical_width==0) vesa_logical_width=vesa_bpp*vesa_data.mode->x_resolution;
                                        	/* if not reported then guess */
    vesa_granularity=vesa_data.mode->win_granularity;
    if(vesa_granularity==0)vesa_granularity=64; /* if not reported then guess */
    if(vesa_chiptype>=1)vesa_linear_base=vesa_data.mode->phys_base_ptr;
    vesa_read_write=0;
    vesa_read_window=0;
    vesa_write_window=0;
    if((vesa_data.mode->win_a_attributes&6)!=6){ 
        vesa_read_write=1;
        if ((vesa_data.mode->win_b_attributes&2) == 2) vesa_read_window=1;
        if ((vesa_data.mode->win_b_attributes&4) == 4) vesa_write_window=1;
    }
    return 0;
}


/* Unlock chipset-specific registers */

static void vesa_unlock(void)
{
}


/* Relock chipset-specific registers */
/* (currently not used) */

static void vesa_lock(void)
{
}


/* Indentify chipset, initialize and return non-zero if detected */

static int vesa_test(void)
{

    if ((getenv("IOPERM") == NULL) && ((iopl(3) < 0)||(ioperm(0,0x400,1)<0))) {
	printf("svgalib(vesa): Cannot get I/O permissions.\n");
	exit(-1);
    }
    
    lrmi_inited=1;
    __svgalib_LRMI_init();
    vesa_data.info = __svgalib_LRMI_alloc_real(sizeof(struct vbe_info_block)
	 + sizeof(struct vbe_mode_info_block));
    vesa_data.mode = (struct vbe_mode_info_block *)(vesa_data.info + 1);
    vesa_r.eax = 0x4f00;
    vesa_r.es = (unsigned int)vesa_data.info >> 4;
    vesa_r.edi = 0;

    __svgalib_LRMI_int(0x10, &vesa_r);
    if (vesa_r.eax!=0x4f) return 0;
    return !vesa_init(0,0,0);
}


/* No r/w paging */
static void vesa_setrdpage(int page)
{
vesa_r.eax=0x4f05;
vesa_r.ebx=vesa_read_window;
vesa_r.edx=page*64/vesa_granularity;
__svgalib_LRMI_int(0x10,&vesa_r);
}
static void vesa_setwrpage(int page)
{
vesa_r.eax=0x4f05;
vesa_r.ebx=vesa_write_window;
vesa_r.edx=page*64/vesa_granularity;
__svgalib_LRMI_int(0x10,&vesa_r);
}


/* Set display start address (not for 16 color modes) */

static void vesa_setdisplaystart(int address)
{
  vesa_r.eax=0x4f07;
  vesa_r.ebx=0;
  vesa_r.ecx=address % vesa_logical_width;
  vesa_r.edx=address / vesa_logical_width;

  __svgalib_LRMI_int(0x10,&vesa_r);

}

/* Set logical scanline length (usually multiple of 8) */

static void vesa_setlogicalwidth(int width)
{
  vesa_r.eax=0x4f06;
  vesa_r.ebx=0;
  vesa_r.ecx=width / vesa_bpp ;
  __svgalib_LRMI_int(0x10,&vesa_r);
  vesa_logical_width=vesa_r.ebx;

}

static int vesa_linear(int op, int param)
{
if (op==LINEAR_ENABLE) {  
  vesa_r.eax=0x4f02;