*((char *)addr) = (char) ch;      video_col++;      if (video_col > (VGA_MAXCOLS-1)) {	 			video_row++;	 			video_col=0;      }   }   /* If we're on the bottom of the secreen, wrap one row */   if (video_row > (VGA_MAXROWS-1))     video_scroll(1);    video_cursor(video_col, video_row);}unsigned char video_set_attr(unsigned char attr){  unsigned char saved_attr = video_attr;  video_attr = attr;  return saved_attr;}unsigned char video_set_attr_xy(unsigned char attr, int x, int y){  unsigned char *addr = video_fb + (x * 80 + y) * 2 + 1;  unsigned char saved_attr = *addr;  *addr = attr;  return saved_attr;}/* put char at xy */void video_putc_xy(char ch, int x, int y){  video_col = x;  video_row = y;  video_putc(ch);}/* put char at xy relative to the position */void video_putc_rxy(char ch, int x, int y){  video_col += x;  video_row += y;  video_putc(ch);}/* put char with attribute at xy */void video_putc_axy(char ch, char attr, int x, int y){  unsigned char saved_attr = video_set_attr(attr);  video_col = x;  video_row = y;  video_putc(ch);  video_set_attr(saved_attr);}void video_puts(const char *s){   while(*s) {      video_putc(*s);      s++;   }}void video_puts_a(const char *s, char attr){  unsigned char saved_attr = video_set_attr(attr);  video_puts(s);  video_set_attr(saved_attr);}void video_puts_xy(const char *s, int x, int y){  video_cursor(x,y);  video_puts(s);}void video_puts_axy(const char *s, char attr, int x, int y){  unsigned char saved_attr = video_set_attr(attr);  video_puts_xy(s, x, y);  video_set_attr(saved_attr);}void video_wipe_ca_area(unsigned char ch, char attr, int x, int y, int w, int h){  int r, c;  /* better to do this as word writes */  unsigned short * addr16 = (unsigned short  *)video_fb + (y * 80 + x);  unsigned short charattr = (unsigned short)ch << 8 | attr;	charattr=vga_swap_short(charattr);  for (r = 0 ; r < h ; r++, addr16 += 80) {    for (c = 0 ; c < w ; c++) {      addr16[c] = charattr;    }  }}void video_wipe_a_area(unsigned char attr, int x, int y, int w, int h){  int r, c;  /* better to do this as word writes */  unsigned short * addr16 = (unsigned short *)video_fb + (y * 80 + x);  for (r = 0 ; r < h ; r++, addr16 += 80) {    for (c = 0 ; c < w ; c++) {      ((char*)addr16)[c*2+1] = attr;    }  }}void video_wipe_c_area(unsigned char ch, int x, int y, int w, int h){  int r, c;  /* better to do this as word writes */  unsigned short * addr16 = (unsigned short  *)video_fb + (y * 80 + x);  for (r = 0 ; r < h ; r++, addr16 += 80) {    for (c = 0 ; c < w ; c++) {      ((char*)addr16)[c*2] = ch;    }  }}/*tl t trl    lbl b br*/typedef struct {  unsigned char tl; /* top left corner */  unsigned char t;  /* top edge */  unsigned char tr; /* top right corner */  unsigned char l;  /* left edge */  unsigned char r;  /* right edge */  unsigned char bl; /* bottom left corner */  unsigned char b;  /* bottom edge */  unsigned char br; /* bottom right corner */} box_chars_t;box_chars_t sbox_chars = {  0xDA, 0xC4, 0xBF,  0xB3,       0xB3,  0xC0, 0xC4, 0xD9};box_chars_t dbox_chars = {  0xC9, 0xCD, 0xBB,  0xBA,       0xBA,  0xC8, 0xCD, 0xBC};static char cmap[] = "0123456789ABCDEF";void video_putchex(char c){  video_putc(cmap[(c >> 4 ) & 0xF]);  video_putc(cmap[c & 0xF]);}void video_putchexl(char c){  video_putc(cmap[c & 0xF]);}void video_putchexh(char c){  video_putc(cmap[(c >> 4) & 0xF]);}#define VGA_CELL_CA(a,c) (((unsigned short)c<<8)|a) /* for BIG endians */void video_gbox_area(box_chars_t *box_chars_p, int x, int y, int w, int h){  int r, c;  /* better to do this as word writes */  unsigned short* addr16 = (unsigned short *)video_fb + (y * VGA_MAXCOLS + x);  for (r = 0 ; r < h ; r++, addr16 += VGA_MAXCOLS) {    if (r == 0) {      addr16[0]   = VGA_CELL_CA(video_attr, box_chars_p->tl);      addr16[w-1] = VGA_CELL_CA(video_attr, box_chars_p->tr);      for (c = 1 ; c < w - 1 ; c++)				addr16[c] = VGA_CELL_CA(video_attr, box_chars_p->t);    } else if (r == h - 1) {      addr16[0] = VGA_CELL_CA(video_attr, box_chars_p->bl);      addr16[w-1] = VGA_CELL_CA(video_attr, box_chars_p->br);      for (c = 1 ; c < w - 1 ; c++)				addr16[c] = VGA_CELL_CA(video_attr, box_chars_p->b);    } else {      addr16[0] = VGA_CELL_CA(video_attr, box_chars_p->l);      addr16[w-1] = VGA_CELL_CA(video_attr, box_chars_p->r);    }  }}/* Writes a box on the screen */void video_box_area(int x, int y, int w, int h) {  video_gbox_area(&sbox_chars, x, y, w, h);}/*writes a box with double lines on the screen */void video_dbox_area(int x, int y, int w, int h) {  video_gbox_area(&dbox_chars, x, y, w, h);}/* routines to set the VGA registers *//* set attributes */void vga_set_attrib(void){	int i;	unsigned char status;	status=in8(STATUS_REG1);	i=0;	while(attr[i].reg!=0xFF) {		out8(ATTRI_INDEX,attr[i].reg);		out8(ATTRI_INDEX,attr[i].val); /* Attribute uses index for index and data */		i++;	}	out8(ATTRI_INDEX,0x20); /* unblank the screen */}/* set CRT Controller Registers */void vga_set_crt(void){	int i;	i=0;	while(crtc[i].reg!=0xFF) {		out8(CRT_INDEX,crtc[i].reg);		out8(CRT_DATA,crtc[i].val);		i++;	}}/* Set Palette Registers (DAC) */void vga_set_dac(void){	int i;	for(i=0;i<256;i++) {		out8(COL_PAL_IND_W,(unsigned char)i);		out8(COL_PAL_DATA,dac[i][0]); /* red */		out8(COL_PAL_DATA,dac[i][1]); /* green */		out8(COL_PAL_DATA,dac[i][2]); /* blue */	}	out8(COL_PAL_MASK,0xff); /* set mask */}/* set Graphic Controller Register */void vga_set_gr(void){	int i;	i=0;	while(grmr[i].reg!=0xFF) {		out8(GR_INDEX,grmr[i].reg);		out8(GR_DATA,grmr[i].val);		i++;	}}/* Set Sequencer Registers */void vga_set_seq(void){	int i;	i=0;	while(seq[i].reg!=0xFF) {		out8(SEQ_INDEX,seq[i].reg);		out8(SEQ_DATA,seq[i].val);		i++;	}}/* Set Extension Registers */void vga_set_xreg(void){	int i;	i=0;	while(xreg[i].reg!=0xFF) {		out8(XREG_INDEX,xreg[i].reg);		out8(XREG_DATA,xreg[i].val);		i++;	}}/************************************************************ * some helping routines */void vga_write_sr(unsigned char reg,unsigned char val){	out8(SEQ_INDEX,reg);	out8(SEQ_DATA,val);}void vga_write_gr(unsigned char reg,unsigned char val){	out8(GR_INDEX,reg);	out8(GR_DATA,val);}void vga_write_cr(unsigned char reg,unsigned char val){	out8(CRT_INDEX,reg);	out8(CRT_DATA,val);}#if 0void video_dump_reg(void){	/* first dump attributes */	int i;	unsigned char status;	printf("Extended Regs:\n");	i=0;	while(xreg[i].reg!=0xFF) {		out8(XREG_INDEX,xreg[i].reg);		status=in8(XREG_DATA);		printf("XR%02X is %02X, should be %02X\n",xreg[i].reg,status,xreg[i].val);		i++;	}	printf("Sequencer Regs:\n");	i=0;	while(seq[i].reg!=0xFF) {		out8(SEQ_INDEX,seq[i].reg);		status=in8(SEQ_DATA);		printf("SR%02X is %02X, should be %02X\n",seq[i].reg,status,seq[i].val);		i++;	}	printf("Graphic Regs:\n");	i=0;	while(grmr[i].reg!=0xFF) {		out8(GR_INDEX,grmr[i].reg);		status=in8(GR_DATA);		printf("GR%02X is %02X, should be %02X\n",grmr[i].reg,status,grmr[i].val);		i++;	}	printf("CRT Regs:\n");	i=0;	while(crtc[i].reg!=0xFF) {		out8(CRT_INDEX,crtc[i].reg);		status=in8(CRT_DATA);		printf("CR%02X is %02X, should be %02X\n",crtc[i].reg,status,crtc[i].val);		i++;	}	printf("Attributes:\n");	status=in8(STATUS_REG1);	i=0;	while(attr[i].reg!=0xFF) {		out8(ATTRI_INDEX,attr[i].reg);		status=in8(ATTRI_DATA);		out8(ATTRI_INDEX,attr[i].val); /* Attribute uses index for index and data */		printf("AR%02X is %02X, should be %02X\n",attr[i].reg,status,attr[i].val);		i++;	}}#endif#endif /* CONFIG_VIDEO */