qd.c

早期freebsd实现

	register which_unit, unit, c;
	int s;

	unit = minor(tp->t_dev);
	which_unit = (unit >> 2) & 0x3;
	unit &= 0x03;

	s = spl5();

	/*
	* If it's currently active, or delaying, no need to do anything. 
	*/
	if (tp->t_state & (TS_TIMEOUT|TS_BUSY|TS_TTSTOP))
		goto out;

	/*
	* Display chars until the queue is empty.
	* Drop input from anything but the console
	* device on the floor.	
	*
	* XXX - this loop is done at spltty.
	*
	*/
	while (tp->t_outq.c_cc) {
		c = getc(&tp->t_outq);
		if (unit == 0)
			blitc(which_unit, (u_char)c);
	}
	/*
	* If there are sleepers, and output has drained below low
	* water mark, wake up the sleepers. 
	*/
	if (tp->t_outq.c_cc <= tp->t_lowat) {
		if (tp->t_state & TS_ASLEEP){
			tp->t_state &= ~TS_ASLEEP;
			wakeup((caddr_t) &tp->t_outq);
		}
	}

	tp->t_state &= ~TS_BUSY;

out:
	splx(s);

} /* qdstart */

/*ARGSUSED*/
qdstop(tp, flag)
	register struct tty *tp;
	int flag;
{
	register int s;

	s = spl5();	/* block intrpts during state modification */
	if (tp->t_state & TS_BUSY)
		if ((tp->t_state & TS_TTSTOP) == 0)
			tp->t_state |= TS_FLUSH;
		else
			tp->t_state &= ~TS_BUSY;
	splx(s);
}

/*
 *  Output a character to the QDSS screen
 */

blitc(unit, chr)
	register unit;
	register u_char chr;
{
	register struct adder *adder;
	register struct dga *dga;
	register int i;
	int nograph = !(qdflags[unit].inuse&GRAPHIC_DEV);
	static short inescape[NQD];

	adder = (struct adder *)qdmap[unit].adder;
	dga = (struct dga *) qdmap[unit].dga;
	/* 
	 * BSD comment: this (&=0177) defeats the extended character 
	 * set code for the glass tty, but if i had the time i would 
	 * spend it ripping out the code completely.  This driver
	 * is too big for its own good.
	 */
	chr &= 0177;
	/*
	 * Cursor addressing (so vi will work).
	 * Decode for "\E=%.%." cursor motion description.
	 * Corresponds to type "qdcons" in /etc/termcap:
	 *
	 *    qd|qdss|qdcons|qdss glass tty (4.4 BSD):\
	 *      :am:do=^J:le=^H:bs:cm=\E=%.%.:cl=1^Z:co#128:li#57::nd=^L:up=^K:
	 *
	 */
	if (inescape[unit] && nograph) {	
		switch (inescape[unit]++) {
		case 1:
			if (chr != '=') {
				/* abort escape sequence */
				inescape[unit] = 0;
				blitc(unit, chr);
			}
			return;
		case 2:
			/* position row */
			cursor[unit].y = CHAR_HEIGHT * chr;
			if (cursor[unit].y > 863 - CHAR_HEIGHT)
				cursor[unit].y = 863 - CHAR_HEIGHT;
			dga->y_cursor = TRANY(cursor[unit].y);
			return;
		case 3:
			/* position column */
			cursor[unit].x = CHAR_WIDTH * chr;
			if (cursor[unit].x > 1024 - CHAR_WIDTH)
				cursor[unit].x = 1023 - CHAR_WIDTH;
			dga->x_cursor = TRANX(cursor[unit].x);
			inescape[unit] = 0;
			return;
		default:
			inescape[unit] = 0;
			blitc(unit, chr);
		}
	}

	switch (chr) {
	case '\r':			/* return char */
		cursor[unit].x = 0;
		if (nograph)
			dga->x_cursor = TRANX(cursor[unit].x);
		return;

	case '\t':			/* tab char */
		for (i = 8 - ((cursor[unit].x >> 3) & 0x07); i > 0; --i) {
			blitc(unit, ' ');
		}
		return;

	case '\n':			/* line feed char */
		if ((cursor[unit].y += CHAR_HEIGHT) > (863 - CHAR_HEIGHT)) {
			if (nograph) {
				cursor[unit].y -= CHAR_HEIGHT;
				scroll_up(adder);
			} else
				cursor[unit].y = 0;
		}
		if (nograph)
			dga->y_cursor = TRANY(cursor[unit].y);
		return;

	case '\b':			/* backspace char */
		if (cursor[unit].x > 0) {
			cursor[unit].x -= CHAR_WIDTH;
			if (nograph)
				dga->x_cursor = TRANX(cursor[unit].x);
		}
		return;
	case CTRL('k'):		/* cursor up */
		if (nograph && cursor[unit].y > 0) {
			cursor[unit].y -= CHAR_HEIGHT;
			dga->y_cursor = TRANY(cursor[unit].y);
		}
		return;

	case CTRL('^'):		/* home cursor */
		if (nograph) {
			cursor[unit].x = 0;
			dga->x_cursor = TRANX(cursor[unit].x);
			cursor[unit].y = 0;
			dga->y_cursor = TRANY(cursor[unit].y);
		}
		return;

	case CTRL('l'):		/* cursor right */
		if (nograph && cursor[unit].x < 1023 - CHAR_WIDTH) {
			cursor[unit].x += CHAR_WIDTH;
			dga->x_cursor = TRANX(cursor[unit].x);
		}
		return;

	case CTRL('z'):		/* clear screen */
		if (nograph) {
			setup_dragon(unit);  	
			clear_qd_screen(unit);
			/* home cursor - termcap seems to assume this */
			cursor[unit].x = 0;
			dga->x_cursor = TRANX(cursor[unit].x);
			cursor[unit].y = 0;
			dga->y_cursor = TRANY(cursor[unit].y);
		}
		return;

	case '\033':		/* start escape sequence */
		if (nograph)
			inescape[unit] = 1;
		return;

	default:
		if ((chr < ' ') || (chr > '~'))
			return;
	}
	/*
	 * setup VIPER operand control registers  
	 */
	write_ID(adder, CS_UPDATE_MASK, 0x0001);  /* select plane #0 */
	write_ID(adder, SRC1_OCR_B,
	EXT_NONE | INT_SOURCE | ID | BAR_SHIFT_DELAY);
	write_ID(adder, CS_UPDATE_MASK, 0x00FE);  /* select other planes */
	write_ID(adder, SRC1_OCR_B,
	EXT_SOURCE | INT_NONE | NO_ID | BAR_SHIFT_DELAY);
	write_ID(adder, CS_UPDATE_MASK, 0x00FF);  /* select all planes */
	write_ID(adder, DST_OCR_B,
	EXT_NONE | INT_NONE | NO_ID | NO_BAR_SHIFT_DELAY);
	write_ID(adder, MASK_1, 0xFFFF);
	write_ID(adder, VIPER_Z_LOAD | FOREGROUND_COLOR_Z, 1);
	write_ID(adder, VIPER_Z_LOAD | BACKGROUND_COLOR_Z, 0);
	adder->x_clip_min = 0;
	adder->x_clip_max = 1024;
	adder->y_clip_min = 0;
	adder->y_clip_max = 864;
	/*
	 * load DESTINATION origin and vectors  
	 */
	adder->fast_dest_dy = 0;
	adder->slow_dest_dx = 0;
	adder->error_1 = 0;
	adder->error_2 = 0;
	adder->rasterop_mode = DST_WRITE_ENABLE | NORMAL;
	(void)wait_status(adder, RASTEROP_COMPLETE);
	adder->destination_x = cursor[unit].x;
	adder->fast_dest_dx = CHAR_WIDTH;
	adder->destination_y = cursor[unit].y;
	adder->slow_dest_dy = CHAR_HEIGHT;
	/*
	 * load SOURCE origin and vectors  
	 */
	if ((chr - ' ') > (CHARS - 1))  {
		printf("Invalid character (x)%x in blitc\n",chr);
		chr = ' ';
	}
	/*
	 * X position is modulo the number of characters per line 
	 */
	adder->source_1_x = FONT_X + 
	    (((chr - ' ') % (MAX_SCREEN_X/CHAR_WIDTH)) * CHAR_WIDTH);
	/*
	 * Point to either first or second row 
	 */
	adder->source_1_y = 2048 - 15 * 
	    (((chr - ' ')/(MAX_SCREEN_X/CHAR_WIDTH)) + 1);
	adder->source_1_dx = CHAR_WIDTH;
	adder->source_1_dy = CHAR_HEIGHT;
	write_ID(adder, LU_FUNCTION_R1, FULL_SRC_RESOLUTION | LF_SOURCE);
	adder->cmd = RASTEROP | OCRB | 0 | S1E | DTE;
	/*
	 * update console cursor coordinates 
	 */
	cursor[unit].x += CHAR_WIDTH;
	if (nograph)
		dga->x_cursor = TRANX(cursor[unit].x);
	if (cursor[unit].x > (1024 - CHAR_WIDTH)) {
		blitc(unit, '\r');
		blitc(unit, '\n');
	}

} /* blitc */

qdreset() { }

/*
 *  INTERRUPT SERVICE ROUTINES
 */

/*
 *  Service "DMA DONE" interrupt condition
 */
qddint(qd)
	register qd;
{
	register struct DMAreq_header *header;
	register struct DMAreq *request;
	register struct dga *dga;
	struct adder *adder;
	int cookie;			/* DMA adrs for QDSS */

	(void)spl4(); 			/* allow interval timer in */

	/*
	* init pointers 
	*/
	header = DMAheader[qd]; 	    /* register for optimization */
	dga = (struct dga *) qdmap[qd].dga;
	adder = (struct adder *) qdmap[qd].adder;

	/*
	* if this interrupt flagged as bogus for interrupt flushing purposes.. 
	*/
	if (DMA_ISIGNORE(header)) {
		DMA_CLRIGNORE(header);
		return;
	}

	/*
	* dump a DMA hardware error message if appropriate
	*/
	if (dga->csr & DMA_ERR) {

		if (dga->csr & PARITY_ERR)
		    printf("qd%d: qddint: DMA hardware parity fault.\n", qd);

		if (dga->csr & BUS_ERR)
		    printf("qd%d: qddint: DMA hardware bus error.\n", qd);
	}

	/*
	* if this was a DMA from user space... 
	*/
	if (qdflags[qd].user_dma) {
		qdflags[qd].user_dma = 0;
		wakeup((caddr_t)&qdflags[qd].user_dma);
		return;
	}

	/*
	* if we're doing DMA request queue services, field the error condition 
	*/
	if (dga->csr & DMA_ERR) {

		dga->csr &= ~0x0600;		/* halt DMA (reset fifo) */
		dga->csr |= DMA_ERR;		/* clear error condition */
		adder->command = CANCEL;	/* cancel adder activity */

		DMA_SETERROR(header);	/* flag error in header status word */
		DMA_CLRACTIVE(header);
		header->DMAreq[header->oldest].DMAdone |= HARD_ERROR;
		header->newest = header->oldest;
		header->used = 0;

		if (qdrsel[qd] && qdflags[qd].selmask & SEL_WRITE) {
			selwakeup(qdrsel[qd], 0);
			qdrsel[qd] = 0;
			qdflags[qd].selmask &= ~SEL_WRITE;
		}

		if (dga->bytcnt_lo != 0) {
			dga->bytcnt_lo = 0;
			dga->bytcnt_hi = 0;
			DMA_SETIGNORE(header);
		}
		return;
	}

	/*
	* if the DMA request queue is now becoming non-full, 
	* wakeup "select" client.
	*/
	if (DMA_ISFULL(header)) {
		if (qdrsel[qd] && qdflags[qd].selmask & SEL_WRITE) {
			selwakeup(qdrsel[qd], 0);
			qdrsel[qd] = 0;
			qdflags[qd].selmask &= ~SEL_WRITE;
		}
	}

	header->DMAreq[header->oldest].DMAdone |= REQUEST_DONE;
	QDlast_DMAtype = header->DMAreq[header->oldest].DMAtype;

	/* check for unexpected interrupt */
	if (DMA_ISEMPTY(header))
	    return;

	DMA_GETEND(header);	/* update request queue indices */

	/*
	* if no more DMA pending, wake up "select" client and exit 
	*/
	if (DMA_ISEMPTY(header)) {

		if (qdrsel[qd] && qdflags[qd].selmask & SEL_WRITE) {
			selwakeup(qdrsel[qd], 0);
			qdrsel[qd] = 0;
			qdflags[qd].selmask &= ~SEL_WRITE;
		}

		DMA_CLRACTIVE(header);  /* flag DMA done */
		return;
	}

	/*
	* initiate next DMA xfer  
	*/
	request = DMA_GETBEGIN(header);
	if (request->DMAtype != QDlast_DMAtype) {
		dga->csr &= ~0x0600;	  /* halt DMA (reset fifo) */
		adder->command = CANCEL;  /* cancel adder activity */
	}


	switch (request->DMAtype) {

	case DISPLIST:
		if (request->DMAtype != QDlast_DMAtype) {
			dga->csr |= DL_ENB;
			dga->csr &= ~(BTOP_ENB | BYTE_DMA);
		}
		break;

	case PTOB:
		if (request->DMAtype != QDlast_DMAtype) {
			if (request->DMAdone & BYTE_PACK)
			    dga->csr |= (PTOB_ENB | BYTE_DMA);
			else {
				dga->csr |= PTOB_ENB;
				dga->csr &= ~BYTE_DMA;
			}
		}
		break;

	case BTOP:
		if (request->DMAtype != QDlast_DMAtype) {
			if (request->DMAdone & BYTE_PACK) {
				dga->csr &= ~DL_ENB;
				dga->csr |= (BTOP_ENB | BYTE_DMA);
			}
			else {
				dga->csr |= BTOP_ENB;
				dga->csr &= ~(BYTE_DMA | DL_ENB);
			}
		}
		break;
	default:
		printf("qd%d: qddint: illegal DMAtype parameter.\n", qd);
		DMA_CLRACTIVE(header);	/* flag DMA done */
		return;
	}

	if (request->DMAdone & COUNT_ZERO) {
		dga->csr &= ~SET_DONE_FIFO;
	} 
	else if (request->DMAdone & FIFO_EMPTY) {
		dga->csr |= SET_DONE_FIFO;
	}

	if (request->DMAdone & WORD_PACK)
	    dga->csr &= ~BYTE_DMA;
	else if (request->DMAdone & BYTE_PACK)
	    dga->csr |= BYTE_DMA;

	dga->csr |= DMA_IE;
	QDlast_DMAtype = request->DMAtype;

	cookie = ((int)request->bufp - (int)header) + (int)header->QBAreg;

	dga->adrs_lo = (short) cookie;
	dga->adrs_hi = (short) (cookie >> 16);

	dga->bytcnt_lo = (short) request->length;
	dga->bytcnt_hi = (short) (request->length >> 16);

	return;
}

/*
 * ADDER interrupt service routine
 */
qdaint(qd)
	register qd;
{
	register struct adder *adder;
	struct color_buf *cbuf;
	int i;
	register struct rgb *rgbp;
	register short *red;
	register short *green;
	register short *blue;

	(void)spl4(); 			/* allow interval timer in */

	adder = (struct adder *) qdmap[qd].adder;

	/*
	* service the vertical blank interrupt (VSYNC bit) by loading 
	* any pending color map load request  
	*/
	if (adder->status & VSYNC) {
		adder->status &= ~VSYNC;	/* clear the interrupt */
		cbuf = color_buf[qd];
		if (cbuf->status & LOAD_COLOR_MAP) {

			red = (short *) qdmap[qd].red;
			green = (short *) qdmap[qd].green;
			blue = (short *) qdmap[qd].blue;

			for (i = cbuf->count, rgbp = cbuf->rgb;
			     --i >= 0; rgbp++) {
				red[rgbp->offset] = (short) rgbp->red;
				green[rgbp->offset] = (short) rgbp->green;
				blue[rgbp->offset] = (short) rgbp->blue;
			}

			cbuf->status &= ~LOAD_COLOR_MAP;
		}
	}

	/*
	* service the scroll interrupt (FRAME_SYNC bit) 
	*/
	if (adder->status & FRAME_SYNC) {
		adder->status &= ~FRAME_SYNC;	/* clear the interrupt */

		if (scroll[qd]->status & LOAD_REGS) {

			for (i = 1000, adder->status = 0; i > 0 &&