xref: /src/sys/dev/rasops/rasops.c

/*	 $NetBSD: rasops.c,v 1.19.4.1 1999/11/15 00:41:18 fvdl Exp $	*/

/*-
 * Copyright (c) 1999 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Andy Doran.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the NetBSD
 *	Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rasops.c,v 1.19.4.1 1999/11/15 00:41:18 fvdl Exp $");

#include "opt_rasops.h"
#include "rasops_glue.h"

#include <sys/types.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>

#include <machine/bswap.h>
#include <machine/endian.h>

#include <dev/wscons/wsdisplayvar.h>
#include <dev/wscons/wsconsio.h>
#include <dev/wsfont/wsfont.h>
#include <dev/rasops/rasops.h>

#ifndef _KERNEL
#include <errno.h>
#endif

/* ANSI colormap (R,G,B). Upper 8 are high-intensity */
u_char rasops_cmap[256*3] = {
	0x00, 0x00, 0x00, /* black */
	0x7f, 0x00, 0x00, /* red */
	0x00, 0x7f, 0x00, /* green */
	0x7f, 0x7f, 0x00, /* brown */
	0x00, 0x00, 0x7f, /* blue */
	0x7f, 0x00, 0x7f, /* magenta */
	0x00, 0x7f, 0x7f, /* cyan */
	0xc7, 0xc7, 0xc7, /* white - XXX too dim? */

	0x7f, 0x7f, 0x7f, /* black */
	0xff, 0x00, 0x00, /* red */
	0x00, 0xff, 0x00, /* green */
	0xff, 0xff, 0x00, /* brown */
	0x00, 0x00, 0xff, /* blue */
	0xff, 0x00, 0xff, /* magenta */
	0x00, 0xff, 0xff, /* cyan */
	0xff, 0xff, 0xff, /* white */
};

/* True if color is gray */
u_char rasops_isgray[16] = {
	1, 0, 0, 0,
	0, 0, 0, 1,
	1, 0, 0, 0,
	0, 0, 0, 1
};

/* Generic functions */
static void	rasops_copyrows __P((void *, int, int, int));
static int	rasops_mapchar __P((void *, int, u_int *));
static void	rasops_cursor __P((void *, int, int, int));
static int	rasops_alloc_cattr __P((void *, int, int, int, long *));
static int	rasops_alloc_mattr __P((void *, int, int, int, long *));
static void	rasops_do_cursor __P((struct rasops_info *));
static void	rasops_init_devcmap __P((struct rasops_info *));

/*
 * Initalize a 'rasops_info' descriptor.
 */
int
rasops_init(ri, wantrows, wantcols)
	struct rasops_info *ri;
	int wantrows, wantcols;
{

#ifdef _KERNEL
	/* Select a font if the caller doesn't care */
	if (ri->ri_font == NULL) {
		int cookie;

		wsfont_init();

		/* Want 8 pixel wide, don't care about aestethics */
		if ((cookie = wsfont_find(NULL, 8, 0, 0)) <= 0)
			cookie = wsfont_find(NULL, 0, 0, 0);

		if (cookie <= 0) {
			printf("rasops_init: font table is empty\n");
			return (-1);
		}

		if (wsfont_lock(cookie, &ri->ri_font,
		    WSFONT_L2R, WSFONT_L2R) <= 0) {
			printf("rasops_init: couldn't lock font\n");
			return (-1);
		}

		ri->ri_wsfcookie = cookie;
	}
#endif

	/* This should never happen in reality... */
#ifdef DEBUG
	if ((int)ri->ri_bits & 3) {
		printf("rasops_init: bits not aligned on 32-bit boundary\n");
		return (-1);
	}

	if ((int)ri->ri_stride & 3) {
		printf("rasops_init: stride not aligned on 32-bit boundary\n");
		return (-1);
	}
#endif

	/* Fix colormap. We need this for the cursor to work. */
	rasops_cmap[255*3+0] = 0xff;
	rasops_cmap[255*3+1] = 0xff;
	rasops_cmap[255*3+2] = 0xff;

	if (rasops_reconfig(ri, wantrows, wantcols))
		return (-1);

	rasops_init_devcmap(ri);
	return (0);
}

/*
 * Reconfigure (because parameters have changed in some way).
 */
int
rasops_reconfig(ri, wantrows, wantcols)
	struct rasops_info *ri;
	int wantrows, wantcols;
{
	int bpp, s;

	s = splhigh();

	if (ri->ri_font->fontwidth > 32 || ri->ri_font->fontwidth < 4)
		panic("rasops_init: fontwidth assumptions botched!\n");

	/* Need this to frob the setup below */
	bpp = (ri->ri_depth == 15 ? 16 : ri->ri_depth);

	if ((ri->ri_flg & RI_CFGDONE) != 0)
		ri->ri_bits = ri->ri_origbits;

	/* Don't care if the caller wants a hideously small console */
	if (wantrows < 10)
		wantrows = 10;

	if (wantcols < 20)
		wantcols = 20;

	/* Now constrain what they get */
	ri->ri_emuwidth = ri->ri_font->fontwidth * wantcols;
	ri->ri_emuheight = ri->ri_font->fontheight * wantrows;

	if (ri->ri_emuwidth > ri->ri_width)
		ri->ri_emuwidth = ri->ri_width;

	if (ri->ri_emuheight > ri->ri_height)
		ri->ri_emuheight = ri->ri_height;

	/* Reduce width until aligned on a 32-bit boundary */
	while ((ri->ri_emuwidth * bpp & 31) != 0)
		ri->ri_emuwidth--;

	ri->ri_cols = ri->ri_emuwidth / ri->ri_font->fontwidth;
	ri->ri_rows = ri->ri_emuheight / ri->ri_font->fontheight;
	ri->ri_emustride = ri->ri_emuwidth * bpp >> 3;
	ri->ri_delta = ri->ri_stride - ri->ri_emustride;
	ri->ri_ccol = 0;
	ri->ri_crow = 0;
	ri->ri_pelbytes = bpp >> 3;

	ri->ri_xscale = (ri->ri_font->fontwidth * bpp) >> 3;
	ri->ri_yscale = ri->ri_font->fontheight * ri->ri_stride;
	ri->ri_fontscale = ri->ri_font->fontheight * ri->ri_font->stride;

#ifdef DEBUG
	if ((ri->ri_delta & 3) != 0)
		panic("rasops_init: ri_delta not aligned on 32-bit boundary");
#endif
	/* Clear the entire display */
	if ((ri->ri_flg & RI_CLEAR) != 0)
		memset(ri->ri_bits, 0, ri->ri_stride * ri->ri_height);

	/* Now centre our window if needs be */
	ri->ri_origbits = ri->ri_bits;

	if ((ri->ri_flg & RI_CENTER) != 0) {
		ri->ri_bits += ((ri->ri_stride - ri->ri_emustride) >> 1) & ~3;
		ri->ri_bits += ((ri->ri_height - ri->ri_emuheight) >> 1) *
		    ri->ri_stride;

		ri->ri_yorigin = (int)(ri->ri_bits - ri->ri_origbits)
		   / ri->ri_stride;
		ri->ri_xorigin = (((int)(ri->ri_bits - ri->ri_origbits)
		   % ri->ri_stride) * bpp) >> 3;
	} else
		ri->ri_xorigin = ri->ri_yorigin = 0;

	/*
	 * Fill in defaults for operations set.  XXX this nukes private
	 * routines used by accelerated fb drivers.
	 */
	ri->ri_ops.mapchar = rasops_mapchar;
	ri->ri_ops.copyrows = rasops_copyrows;
	ri->ri_ops.copycols = rasops_copycols;
	ri->ri_ops.erasecols = rasops_erasecols;
	ri->ri_ops.eraserows = rasops_eraserows;
	ri->ri_ops.cursor = rasops_cursor;
	ri->ri_do_cursor = rasops_do_cursor;

	if (ri->ri_depth < 8 || (ri->ri_flg & RI_FORCEMONO) != 0) {
		ri->ri_ops.alloc_attr = rasops_alloc_mattr;
		ri->ri_caps = WSATTR_UNDERLINE | WSATTR_REVERSE;
	} else {
		ri->ri_ops.alloc_attr = rasops_alloc_cattr;
		ri->ri_caps = WSATTR_UNDERLINE | WSATTR_HILIT |
		    WSATTR_WSCOLORS | WSATTR_REVERSE;
	}

	switch (ri->ri_depth) {
#if NRASOPS1 > 0
	case 1:
		rasops1_init(ri);
		break;
#endif
#if NRASOPS2 > 0
	case 2:
		rasops2_init(ri);
		break;
#endif
#if NRASOPS8 > 0
	case 8:
		rasops8_init(ri);
		break;
#endif
#if NRASOPS15 > 0 || NRASOPS16 > 0
	case 15:
	case 16:
		rasops15_init(ri);
		break;
#endif
#if NRASOPS24 > 0
	case 24:
		rasops24_init(ri);
		break;
#endif
#if NRASOPS32 > 0
	case 32:
		rasops32_init(ri);
		break;
#endif
	default:
		ri->ri_flg &= ~RI_CFGDONE;
		splx(s);
		return (-1);
	}

	ri->ri_flg |= RI_CFGDONE;
	splx(s);
	return (0);
}

/*
 * Map a character.
 */
static int
rasops_mapchar(cookie, c, cp)
	void *cookie;
	int c;
	u_int *cp;
{
	struct rasops_info *ri;

	ri = (struct rasops_info *)cookie;

#ifdef DIAGNOSTIC
	if (ri->ri_font == NULL)
		panic("rasops_mapchar: no font selected\n");
#endif

	if (c < ri->ri_font->firstchar) {
		*cp = ' ';
		return (0);
	}

	if (c - ri->ri_font->firstchar >= ri->ri_font->numchars) {
		*cp = ' ';
		return (0);
	}

	*cp = c;
	return (5);
}

/*
 * Allocate a color attribute.
 */
static int
rasops_alloc_cattr(cookie, fg, bg, flg, attr)
	void *cookie;
	int fg, bg, flg;
	long *attr;
{
	int swap;

#ifdef RASOPS_CLIPPING
	fg &= 7;
	bg &= 7;
#endif
	if ((flg & WSATTR_BLINK) != 0)
		return (EINVAL);

	if ((flg & WSATTR_REVERSE) != 0) {
		swap = fg;
		fg = bg;
		bg = swap;
	}

	if ((flg & WSATTR_HILIT) != 0)
		fg += 8;

	flg = ((flg & WSATTR_UNDERLINE) ? 1 : 0);

	if (rasops_isgray[fg])
		flg |= 2;

	if (rasops_isgray[bg])
		flg |= 4;

	*attr = (bg << 16) | (fg << 24) | flg;
	return (0);
}

/*
 * Allocate a mono attribute.
 */
static int
rasops_alloc_mattr(cookie, fg, bg, flg, attr)
	void *cookie;
	int fg, bg, flg;
	long *attr;
{
	int swap;

	fg = (fg == WSCOL_BLACK ? 0 : 1);
	bg = (bg == WSCOL_BLACK ? 0 : 1);

	if ((flg & (WSATTR_BLINK | WSATTR_HILIT)) != 0)
		return (EINVAL);

	if ((flg & WSATTR_REVERSE) != 0) {
		swap = fg;
		fg = bg;
		bg = swap;
	}

	*attr = (bg << 16) | (fg << 24) | ((flg & WSATTR_UNDERLINE) ? 7 : 6);
	return (0);
}

/*
 * Copy rows.
 */
static void
rasops_copyrows(cookie, src, dst, num)
	void *cookie;
	int src, dst, num;
{
	int32_t *sp, *dp, *srp, *drp;
	struct rasops_info *ri;
	int n8, n1, cnt, delta;

	ri = (struct rasops_info *)cookie;

#ifdef RASOPS_CLIPPING
	if (dst == src)
		return;

	if (src < 0) {
		num += src;
		src = 0;
	}

	if ((src + num) > ri->ri_rows)
		num = ri->ri_rows - src;

	if (dst < 0) {
		num += dst;
		dst = 0;
	}

	if ((dst + num) > ri->ri_rows)
		num = ri->ri_rows - dst;

	if (num <= 0)
		return;
#endif

	num *= ri->ri_font->fontheight;
	n8 = ri->ri_emustride >> 5;
	n1 = (ri->ri_emustride >> 2) & 7;

	if (dst < src) {
		srp = (int32_t *)(ri->ri_bits + src * ri->ri_yscale);
		drp = (int32_t *)(ri->ri_bits + dst * ri->ri_yscale);
		delta = ri->ri_stride;
	} else {
		src = ri->ri_font->fontheight * src + num - 1;
		dst = ri->ri_font->fontheight * dst + num - 1;
		srp = (int32_t *)(ri->ri_bits + src * ri->ri_stride);
		drp = (int32_t *)(ri->ri_bits + dst * ri->ri_stride);
		delta = -ri->ri_stride;
	}

	while (num--) {
		dp = drp;
		sp = srp;
		DELTA(drp, delta, int32_t *);
		DELTA(srp, delta, int32_t *);

		for (cnt = n8; cnt; cnt--) {
			dp[0] = sp[0];
			dp[1] = sp[1];
			dp[2] = sp[2];
			dp[3] = sp[3];
			dp[4] = sp[4];
			dp[5] = sp[5];
			dp[6] = sp[6];
			dp[7] = sp[7];
			dp += 8;
			sp += 8;
		}

		for (cnt = n1; cnt; cnt--)
			*dp++ = *sp++;
	}
}

/*
 * Copy columns. This is slow, and hard to optimize due to alignment,
 * and the fact that we have to copy both left->right and right->left.
 * We simply cop-out here and use bcopy(), since it handles all of
 * these cases anyway.
 */
void
rasops_copycols(cookie, row, src, dst, num)
	void *cookie;
	int row, src, dst, num;
{
	struct rasops_info *ri;
	u_char *sp, *dp;
	int height;

	ri = (struct rasops_info *)cookie;

#ifdef RASOPS_CLIPPING
	if (dst == src)
		return;

	/* Catches < 0 case too */
	if ((unsigned)row >= (unsigned)ri->ri_rows)
		return;

	if (src < 0) {
		num += src;
		src = 0;
	}

	if ((src + num) > ri->ri_cols)
		num = ri->ri_cols - src;

	if (dst < 0) {
		num += dst;
		dst = 0;
	}

	if ((dst + num) > ri->ri_cols)
		num = ri->ri_cols - dst;

	if (num <= 0)
		return;
#endif

	num *= ri->ri_xscale;
	row *= ri->ri_yscale;
	height = ri->ri_font->fontheight;

	sp = ri->ri_bits + row + src * ri->ri_xscale;
	dp = ri->ri_bits + row + dst * ri->ri_xscale;

	while (height--) {
		bcopy(sp, dp, num);
		dp += ri->ri_stride;
		sp += ri->ri_stride;
	}
}

/*
 * Turn cursor off/on.
 */
static void
rasops_cursor(cookie, on, row, col)
	void *cookie;
	int on, row, col;
{
	struct rasops_info *ri;

	ri = (struct rasops_info *)cookie;

	/* Turn old cursor off */
	if ((ri->ri_flg & RI_CURSOR) != 0)
#ifdef RASOPS_CLIPPING
		if ((ri->ri_flg & RI_CURSORCLIP) == 0)
#endif
			ri->ri_do_cursor(ri);

	/* Select new cursor */
#ifdef RASOPS_CLIPPING
	ri->ri_flg &= ~RI_CURSORCLIP;

	if (row < 0 || row >= ri->ri_rows)
		ri->ri_flg |= RI_CURSORCLIP;
	else if (col < 0 || col >= ri->ri_cols)
		ri->ri_flg |= RI_CURSORCLIP;
#endif
	ri->ri_crow = row;
	ri->ri_ccol = col;

	if (on) {
		ri->ri_flg |= RI_CURSOR;
#ifdef RASOPS_CLIPPING
		if ((ri->ri_flg & RI_CURSORCLIP) == 0)
#endif
			ri->ri_do_cursor(ri);
	} else
		ri->ri_flg &= ~RI_CURSOR;
}

/*
 * Make the device colormap
 */
static void
rasops_init_devcmap(ri)
	struct rasops_info *ri;
{
	u_char *p;
	int i, c;

	switch (ri->ri_depth) {
	case 1:
		ri->ri_devcmap[0] = 0;
		for (i = 1; i < 16; i++)
			ri->ri_devcmap[i] = -1;
		return;

	case 2:
		for (i = 1; i < 15; i++)
			ri->ri_devcmap[i] = 0xaaaaaaaa;

		ri->ri_devcmap[0] = 0;
		ri->ri_devcmap[8] = 0x55555555;
		ri->ri_devcmap[15] = -1;
		return;

	case 8:
		for (i = 0; i < 16; i++)
			ri->ri_devcmap[i] = i | (i<<8) | (i<<16) | (i<<24);
		return;
	}

	p = rasops_cmap;

	for (i = 0; i < 16; i++, p++) {
		if (ri->ri_rnum <= 8)
			c = (*p >> (8 - ri->ri_rnum)) << ri->ri_rpos;
		else
			c = (*p << (ri->ri_rnum - 8)) << ri->ri_rpos;

		if (ri->ri_gnum <= 8)
			c |= (*p >> (8 - ri->ri_gnum)) << ri->ri_gpos;
		else
			c |= (*p << (ri->ri_gnum - 8)) << ri->ri_gpos;

		if (ri->ri_bnum <= 8)
			c |= (*p >> (8 - ri->ri_bnum)) << ri->ri_bpos;
		else
			c |= (*p << (ri->ri_bnum - 8)) << ri->ri_bpos;

		/* Fill the word for generic routines, which want this */
		if (ri->ri_depth == 24)
			c = c | ((c & 0xff) << 24);
		else if (ri->ri_depth <= 16)
			c = c | (c << 16);

		/* 24bpp does bswap on the fly. {32,16,15}bpp do it here. */
		if ((ri->ri_flg & RI_BSWAP) == 0)
			ri->ri_devcmap[i] = c;
		else if (ri->ri_depth == 32)
			ri->ri_devcmap[i] = bswap32(c);
		else if (ri->ri_depth == 16 || ri->ri_depth == 15)
			ri->ri_devcmap[i] = bswap16(c);
		else
			ri->ri_devcmap[i] = c;
	}
}

/*
 * Unpack a rasops attribute
 */
void
rasops_unpack_attr(attr, fg, bg, underline)
	long attr;
	int *fg, *bg, *underline;
{

	*fg = ((u_int)attr >> 24) & 15;
	*bg = ((u_int)attr >> 16) & 15;
	*underline = (u_int)attr & 1;
}

/*
 * Erase rows. This isn't static, since 24-bpp uses it in special cases.
 */
void
rasops_eraserows(cookie, row, num, attr)
	void *cookie;
	int row, num;
	long attr;
{
	struct rasops_info *ri;
	int np, nw, cnt, delta;
	int32_t *dp, clr;

	ri = (struct rasops_info *)cookie;

#ifdef RASOPS_CLIPPING
	if (row < 0) {
		num += row;
		row = 0;
	}

	if ((row + num) > ri->ri_rows)
		num = ri->ri_rows - row;

	if (num <= 0)
		return;
#endif

	clr = ri->ri_devcmap[(attr >> 16) & 15];

	/*
	 * XXX The wsdisplay_emulops interface seems a little deficient in
	 * that there is no way to clear the *entire* screen. We provide a
	 * workaround here: if the entire console area is being cleared, and
	 * the RI_FULLCLEAR flag is set, clear the entire display.
	 */
	if (num == ri->ri_rows && (ri->ri_flg & RI_FULLCLEAR) != 0) {
		np = ri->ri_stride >> 5;
		nw = (ri->ri_stride >> 2) & 7;
		num = ri->ri_height;
		dp = (int32_t *)ri->ri_origbits;
		delta = 0;
	} else {
		np = ri->ri_emustride >> 5;
		nw = (ri->ri_emustride >> 2) & 7;
		num *= ri->ri_font->fontheight;
		dp = (int32_t *)(ri->ri_bits + row * ri->ri_yscale);
		delta = ri->ri_delta;
	}

	while (num--) {
		for (cnt = np; cnt; cnt--) {
			dp[0] = clr;
			dp[1] = clr;
			dp[2] = clr;
			dp[3] = clr;
			dp[4] = clr;
			dp[5] = clr;
			dp[6] = clr;
			dp[7] = clr;
			dp += 8;
		}

		for (cnt = nw; cnt; cnt--) {
			*(int32_t *)dp = clr;
			DELTA(dp, 4, int32_t *);
		}

		DELTA(dp, delta, int32_t *);
	}
}

/*
 * Actually turn the cursor on or off. This does the dirty work for
 * rasops_cursor().
 */
static void
rasops_do_cursor(ri)
	struct rasops_info *ri;
{
	int full1, height, cnt, slop1, slop2, row, col;
	u_char *dp, *rp;

	row = ri->ri_crow;
	col = ri->ri_ccol;

	rp = ri->ri_bits + row * ri->ri_yscale + col * ri->ri_xscale;
	height = ri->ri_font->fontheight;
	slop1 = (4 - ((int)rp & 3)) & 3;

	if (slop1 > ri->ri_xscale)
		slop1 = ri->ri_xscale;

	slop2 = (ri->ri_xscale - slop1) & 3;
	full1 = (ri->ri_xscale - slop1 - slop2) >> 2;

	if ((slop1 | slop2) == 0) {
		/* A common case */
		while (height--) {
			dp = rp;
			rp += ri->ri_stride;

			for (cnt = full1; cnt; cnt--) {
				*(int32_t *)dp ^= ~0;
				dp += 4;
			}
		}
	} else {
		/* XXX this is stupid.. use masks instead */
		while (height--) {
			dp = rp;
			rp += ri->ri_stride;

			if (slop1 & 1)
				*dp++ ^= ~0;

			if (slop1 & 2) {
				*(int16_t *)dp ^= ~0;
				dp += 2;
			}

			for (cnt = full1; cnt; cnt--) {
				*(int32_t *)dp ^= ~0;
				dp += 4;
			}

			if (slop2 & 1)
				*dp++ ^= ~0;

			if (slop2 & 2)
				*(int16_t *)dp ^= ~0;
		}
	}
}

/*
 * Erase columns.
 */
void
rasops_erasecols(cookie, row, col, num, attr)
	void *cookie;
	int row, col, num;
	long attr;
{
	int n8, height, cnt, slop1, slop2, clr;
	struct rasops_info *ri;
	int32_t *rp, *dp;

	ri = (struct rasops_info *)cookie;

#ifdef RASOPS_CLIPPING
	if ((unsigned)row >= (unsigned)ri->ri_rows)
		return;

	if (col < 0) {
		num += col;
		col = 0;
	}

	if ((col + num) > ri->ri_cols)
		num = ri->ri_cols - col;

	if (num <= 0)
		return;
#endif

	num = num * ri->ri_xscale;
	rp = (int32_t *)(ri->ri_bits + row*ri->ri_yscale + col*ri->ri_xscale);
	height = ri->ri_font->fontheight;
	clr = ri->ri_devcmap[(attr >> 16) & 15];

	/* Don't bother using the full loop for <= 32 pels */
	if (num <= 32) {
		if (((num | ri->ri_xscale) & 3) == 0) {
			/* Word aligned blt */
			num >>= 2;

			while (height--) {
				dp = rp;
				DELTA(rp, ri->ri_stride, int32_t *);

				for (cnt = num; cnt; cnt--)
					*dp++ = clr;
			}
		} else if (((num | ri->ri_xscale) & 1) == 0) {
			/*
			 * Halfword aligned blt. This is needed so the
			 * 15/16 bit ops can use this function.
			 */
			num >>= 1;

			while (height--) {
				dp = rp;
				DELTA(rp, ri->ri_stride, int32_t *);

				for (cnt = num; cnt; cnt--) {
					*(int16_t *)dp = clr;
					DELTA(dp, 2, int32_t *);
				}
			}
		} else {
			while (height--) {
				dp = rp;
				DELTA(rp, ri->ri_stride, int32_t *);

				for (cnt = num; cnt; cnt--) {
					*(u_char *)dp = clr;
					DELTA(dp, 1, int32_t *);
				}
			}
		}

		return;
	}

	slop1 = (4 - ((int)rp & 3)) & 3;
	slop2 = (num - slop1) & 3;
	num -= slop1 + slop2;
	n8 = num >> 5;
	num = (num >> 2) & 7;

	while (height--) {
		dp = rp;
		DELTA(rp, ri->ri_stride, int32_t *);

		/* Align span to 4 bytes */
		if (slop1 & 1) {
			*(u_char *)dp = clr;
			DELTA(dp, 1, int32_t *);
		}

		if (slop1 & 2) {
			*(int16_t *)dp = clr;
			DELTA(dp, 2, int32_t *);
		}

		/* Write 32 bytes per loop */
		for (cnt = n8; cnt; cnt--) {
			dp[0] = clr;
			dp[1] = clr;
			dp[2] = clr;
			dp[3] = clr;
			dp[4] = clr;
			dp[5] = clr;
			dp[6] = clr;
			dp[7] = clr;
			dp += 8;
		}

		/* Write 4 bytes per loop */
		for (cnt = num; cnt; cnt--)
			*dp++ = clr;

		/* Write unaligned trailing slop */
		if (slop2 & 1) {
			*(u_char *)dp = clr;
			DELTA(dp, 1, int32_t *);
		}

		if (slop2 & 2)
			*(int16_t *)dp = clr;
	}
}