xref: /netbsd-src/sys/dev/sbus/tcx.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /*	$NetBSD: tcx.c,v 1.28 2009/03/18 17:06:50 cegger Exp $ */
2 
3 /*
4  *  Copyright (c) 1996,1998 The NetBSD Foundation, Inc.
5  *  All rights reserved.
6  *
7  *  This code is derived from software contributed to The NetBSD Foundation
8  *  by Paul Kranenburg.
9  *
10  *  Redistribution and use in source and binary forms, with or without
11  *  modification, are permitted provided that the following conditions
12  *  are met:
13  *  1. Redistributions of source code must retain the above copyright
14  *     notice, this list of conditions and the following disclaimer.
15  *  2. Redistributions in binary form must reproduce the above copyright
16  *     notice, this list of conditions and the following disclaimer in the
17  *     documentation and/or other materials provided with the distribution.
18  *
19  *  THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  *  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  *  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  *  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  *  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  *  POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * color display (TCX) driver.
34  *
35  * Does not handle interrupts, even though they can occur.
36  *
37  * XXX should defer colormap updates to vertical retrace interrupts
38  */
39 
40 #include <sys/cdefs.h>
41 __KERNEL_RCSID(0, "$NetBSD: tcx.c,v 1.28 2009/03/18 17:06:50 cegger Exp $");
42 
43 /*
44  * define for cg8 emulation on S24 (24-bit version of tcx) for the SS5;
45  * it is bypassed on the 8-bit version (onboard framebuffer for SS4)
46  */
47 #undef TCX_CG8
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/buf.h>
52 #include <sys/device.h>
53 #include <sys/ioctl.h>
54 #include <sys/malloc.h>
55 #include <sys/mman.h>
56 #include <sys/tty.h>
57 #include <sys/conf.h>
58 
59 #ifdef DEBUG
60 #include <sys/proc.h>
61 #include <sys/syslog.h>
62 #endif
63 
64 #include <sys/bus.h>
65 #include <machine/autoconf.h>
66 
67 #include <dev/sun/fbio.h>
68 #include <dev/sun/fbvar.h>
69 #include <dev/sun/btreg.h>
70 #include <dev/sun/btvar.h>
71 
72 #include <dev/sbus/sbusvar.h>
73 #include <dev/sbus/tcxreg.h>
74 
75 /* per-display variables */
76 struct tcx_softc {
77 	struct device	sc_dev;		/* base device */
78 	struct sbusdev	sc_sd;		/* sbus device */
79 	struct fbdevice	sc_fb;		/* frame buffer device */
80 	bus_space_tag_t	sc_bustag;
81 	struct openprom_addr sc_physadr[TCX_NREG];/* phys addr of h/w */
82 
83 	volatile struct bt_regs *sc_bt;	/* Brooktree registers */
84 	volatile struct tcx_thc *sc_thc;/* THC registers */
85 #ifdef TCX_CG8
86 	volatile ulong *sc_cplane;	/* framebuffer with control planes */
87 #endif
88 	short	sc_8bit;		/* true if 8-bit hardware */
89 	short	sc_blanked;		/* true if blanked */
90 	union	bt_cmap sc_cmap;	/* Brooktree color map */
91 };
92 
93 /*
94  * The S24 provides the framebuffer RAM mapped in three ways:
95  * 26 bits per pixel, in 32-bit words; the low-order 24 bits are
96  * blue, green, and red values, and the other two bits select the
97  * display modes, per pixel);
98  * 24 bits per pixel, in 32-bit words; the high-order byte reads as
99  * zero, and is ignored on writes (so the mode bits cannot be altered);
100  * 8 bits per pixel, unpadded; writes to this space do not modify the
101  * other 18 bits.
102  */
103 #define TCX_CTL_8_MAPPED	0x00000000	/* 8 bits, uses color map */
104 #define TCX_CTL_24_MAPPED	0x01000000	/* 24 bits, uses color map */
105 #define TCX_CTL_24_LEVEL	0x03000000	/* 24 bits, ignores color map */
106 #define TCX_CTL_PIXELMASK	0x00FFFFFF	/* mask for index/level */
107 
108 /* autoconfiguration driver */
109 static void	tcxattach(struct device *, struct device *, void *);
110 static int	tcxmatch(struct device *, struct cfdata *, void *);
111 static void	tcx_unblank(struct device *);
112 
113 CFATTACH_DECL(tcx, sizeof(struct tcx_softc),
114     tcxmatch, tcxattach, NULL, NULL);
115 
116 extern struct cfdriver tcx_cd;
117 
118 dev_type_open(tcxopen);
119 dev_type_close(tcxclose);
120 dev_type_ioctl(tcxioctl);
121 dev_type_mmap(tcxmmap);
122 
123 const struct cdevsw tcx_cdevsw = {
124 	tcxopen, tcxclose, noread, nowrite, tcxioctl,
125 	nostop, notty, nopoll, tcxmmap, nokqfilter,
126 };
127 
128 /* frame buffer generic driver */
129 static struct fbdriver tcx_fbdriver = {
130 	tcx_unblank, tcxopen, tcxclose, tcxioctl, nopoll, tcxmmap,
131 	nokqfilter
132 };
133 
134 static void tcx_reset(struct tcx_softc *);
135 static void tcx_loadcmap(struct tcx_softc *, int, int);
136 
137 #define OBPNAME	"SUNW,tcx"
138 
139 #ifdef TCX_CG8
140 /*
141  * For CG8 emulation, we map the 32-bit-deep framebuffer at an offset of
142  * 256K; the cg8 space begins with a mono overlay plane and an overlay
143  * enable plane (128K bytes each, 1 bit per pixel), immediately followed
144  * by the color planes, 32 bits per pixel.  We also map just the 32-bit
145  * framebuffer at 0x04000000 (TCX_USER_RAM_COMPAT), for compatibility
146  * with the cg8 driver.
147  */
148 #define	TCX_CG8OVERLAY	(256 * 1024)
149 #define	TCX_SIZE_DFB32	(1152 * 900 * 4) /* max size of the framebuffer */
150 #endif
151 
152 /*
153  * Match a tcx.
154  */
155 int
156 tcxmatch(struct device *parent, struct cfdata *cf, void *aux)
157 {
158 	struct sbus_attach_args *sa = aux;
159 
160 	return (strcmp(sa->sa_name, OBPNAME) == 0);
161 }
162 
163 /*
164  * Attach a display.
165  */
166 void
167 tcxattach(struct device *parent, struct device *self, void *args)
168 {
169 	struct tcx_softc *sc = device_private(self);
170 	struct sbus_attach_args *sa = args;
171 	int node, ramsize;
172 	volatile struct bt_regs *bt;
173 	struct fbdevice *fb = &sc->sc_fb;
174 	bus_space_handle_t bh;
175 	int isconsole;
176 
177 	sc->sc_bustag = sa->sa_bustag;
178 	node = sa->sa_node;
179 
180 	fb->fb_driver = &tcx_fbdriver;
181 	fb->fb_device = &sc->sc_dev;
182 	/* Mask out invalid flags from the user. */
183 	fb->fb_flags = device_cfdata(&sc->sc_dev)->cf_flags & FB_USERMASK;
184 	/*
185 	 * The onboard framebuffer on the SS4 supports only 8-bit mode;
186 	 * it can be distinguished from the S24 card for the SS5 by the
187 	 * presence of the "tcx-8-bit" attribute on the SS4 version.
188 	 */
189 	sc->sc_8bit = node_has_property(node, "tcx-8-bit");
190 #ifdef TCX_CG8
191 	if (sc->sc_8bit) {
192 #endif
193 		/*
194 		 * cg8 emulation is either not compiled in or not supported
195 		 * on this hardware.  Report values for the 8-bit framebuffer
196 		 * so cg3 emulation works.  (If this hardware supports
197 		 * 24-bit mode, the 24-bit framebuffer will also be available)
198 		 */
199 		fb->fb_type.fb_depth = 8;
200 		fb_setsize_obp(fb, fb->fb_type.fb_depth, 1152, 900, node);
201 
202 		ramsize = fb->fb_type.fb_height * fb->fb_linebytes;
203 #ifdef TCX_CG8
204 	} else {
205 		/*
206 		 * for cg8 emulation, unconditionally report the depth as
207 		 * 32 bits, but use the height and width reported by the
208 		 * boot prom.  cg8 users want to see the full size of
209 		 * overlay planes plus color planes included in the
210 		 * reported framebuffer size.
211 		 */
212 		fb->fb_type.fb_depth = 32;
213 		fb_setsize_obp(fb, fb->fb_type.fb_depth, 1152, 900, node);
214 		fb->fb_linebytes =
215 			(fb->fb_type.fb_width * fb->fb_type.fb_depth) / 8;
216 		ramsize = TCX_CG8OVERLAY +
217 			(fb->fb_type.fb_height * fb->fb_linebytes);
218 	}
219 #endif
220 	fb->fb_type.fb_cmsize = 256;
221 	fb->fb_type.fb_size = ramsize;
222 	printf(": %s, %d x %d", OBPNAME,
223 		fb->fb_type.fb_width,
224 		fb->fb_type.fb_height);
225 #ifdef TCX_CG8
226 	/*
227 	 * if cg8 emulation is enabled, say so; but if hardware can't
228 	 * emulate cg8, explain that instead
229 	 */
230 	printf( (sc->sc_8bit)?
231 		" (8-bit only)" :
232 		" (emulating cg8)");
233 #endif
234 
235 	/*
236 	 * XXX - should be set to FBTYPE_TCX.
237 	 * XXX For CG3 emulation to work in current (96/6) X11 servers,
238 	 * XXX `fbtype' must point to an "unregocnised" entry.
239 	 */
240 #ifdef TCX_CG8
241 	if (sc->sc_8bit) {
242 		fb->fb_type.fb_type = FBTYPE_RESERVED3;
243 	} else {
244 		fb->fb_type.fb_type = FBTYPE_MEMCOLOR;
245 	}
246 #else
247 	fb->fb_type.fb_type = FBTYPE_RESERVED3;
248 #endif
249 
250 
251 	if (sa->sa_nreg != TCX_NREG) {
252 		printf("%s: only %d register sets\n",
253 			device_xname(self), sa->sa_nreg);
254 		return;
255 	}
256 	memcpy( sc->sc_physadr, sa->sa_reg,
257 	      sa->sa_nreg * sizeof(struct openprom_addr));
258 
259 	/* XXX - fix THC and TEC offsets */
260 	sc->sc_physadr[TCX_REG_TEC].oa_base += 0x1000;
261 	sc->sc_physadr[TCX_REG_THC].oa_base += 0x1000;
262 
263 	/* Map the register banks we care about */
264 	if (sbus_bus_map(sa->sa_bustag,
265 			 sc->sc_physadr[TCX_REG_THC].oa_space,
266 			 sc->sc_physadr[TCX_REG_THC].oa_base,
267 			 sizeof (struct tcx_thc),
268 			 BUS_SPACE_MAP_LINEAR, &bh) != 0) {
269 		printf("tcxattach: cannot map thc registers\n");
270 		return;
271 	}
272 	sc->sc_thc = (volatile struct tcx_thc *)
273 		bus_space_vaddr(sa->sa_bustag, bh);
274 
275 	if (sbus_bus_map(sa->sa_bustag,
276 			 sc->sc_physadr[TCX_REG_CMAP].oa_space,
277 			 sc->sc_physadr[TCX_REG_CMAP].oa_base,
278 			 sizeof (struct bt_regs),
279 			 BUS_SPACE_MAP_LINEAR, &bh) != 0) {
280 		printf("tcxattach: cannot map bt registers\n");
281 		return;
282 	}
283 	sc->sc_bt = bt = (volatile struct bt_regs *)
284 		bus_space_vaddr(sa->sa_bustag, bh);
285 
286 #ifdef TCX_CG8
287 	if (!sc->sc_8bit) {
288 		if (sbus_bus_map(sa->sa_bustag,
289 			 sc->sc_physadr[TCX_REG_RDFB32].oa_space,
290 			 sc->sc_physadr[TCX_REG_RDFB32].oa_base,
291 			 TCX_SIZE_DFB32,
292 			 BUS_SPACE_MAP_LINEAR,
293 			 &bh) != 0) {
294 			printf("tcxattach: cannot map control planes\n");
295 			return;
296 		}
297 		sc->sc_cplane = (volatile ulong *)bh;
298 	}
299 #endif
300 
301 	isconsole = fb_is_console(node);
302 
303 	printf(", id %d, rev %d, sense %d",
304 		(sc->sc_thc->thc_config & THC_CFG_FBID) >> THC_CFG_FBID_SHIFT,
305 		(sc->sc_thc->thc_config & THC_CFG_REV) >> THC_CFG_REV_SHIFT,
306 		(sc->sc_thc->thc_config & THC_CFG_SENSE) >> THC_CFG_SENSE_SHIFT
307 	);
308 
309 	/* reset cursor & frame buffer controls */
310 	tcx_reset(sc);
311 
312 	/* Initialize the default color map. */
313 	bt_initcmap(&sc->sc_cmap, 256);
314 	tcx_loadcmap(sc, 0, 256);
315 
316 	/* enable video */
317 	sc->sc_thc->thc_hcmisc |= THC_MISC_VIDEN;
318 
319 	if (isconsole) {
320 		printf(" (console)\n");
321 	} else
322 		printf("\n");
323 
324 	sbus_establish(&sc->sc_sd, &sc->sc_dev);
325 	fb_attach(&sc->sc_fb, isconsole);
326 }
327 
328 #ifdef TCX_CG8
329 /*
330  * keep track of the number of opens, so we can switch to 24-bit mode
331  * when the device is first opened, and return to 8-bit mode on the
332  * last close.  (stolen from cgfourteen driver...)  There can only be
333  * one TCX per system, so we only need one flag.
334  */
335 static int tcx_opens = 0;
336 #endif
337 
338 int
339 tcxopen(dev_t dev, int flags, int mode, struct lwp *l)
340 {
341 #ifdef TCX_CG8
342 	int unit = minor(dev);
343 	struct tcx_softc *sc;
344 	int i, s, oldopens;
345 	volatile ulong *cptr;
346 	struct fbdevice *fb;
347 
348 	sc = device_lookup_private(&tcx_cd, unit);
349 	if (!sc)
350 		return (ENXIO);
351 	if (!sc->sc_8bit) {
352 		s = splhigh();
353 		oldopens = tcx_opens++;
354 		splx(s);
355 		if (oldopens == 0) {
356 			/*
357 			 * rewrite the control planes to select 24-bit mode
358 			 * and clear the screen
359 			 */
360 			fb = &sc->sc_fb;
361 			i = fb->fb_type.fb_height * fb->fb_type.fb_width;
362 			cptr = sc->sc_cplane;
363 			while (--i >= 0)
364 				*cptr++ = TCX_CTL_24_LEVEL;
365 		}
366 	}
367 #endif
368 	return (0);
369 }
370 
371 int
372 tcxclose(dev_t dev, int flags, int mode, struct lwp *l)
373 {
374 	struct tcx_softc *sc = device_lookup_private(&tcx_cd, minor(dev));
375 #ifdef TCX_CG8
376 	int i, s, opens;
377 	volatile ulong *cptr;
378 	struct fbdevice *fb;
379 #endif
380 
381 	tcx_reset(sc);
382 #ifdef TCX_CG8
383 	if (!sc->sc_8bit) {
384 		s = splhigh();
385 		opens = --tcx_opens;
386 		if (tcx_opens <= 0)
387 			opens = tcx_opens = 0;
388 		splx(s);
389 		if (opens == 0) {
390 			/*
391 			 * rewrite the control planes to select 8-bit mode,
392 			 * preserving the contents of the screen.
393 			 * (or we could just bzero the whole thing...)
394 			 */
395 			fb = &sc->sc_fb;
396 			i = fb->fb_type.fb_height * fb->fb_type.fb_width;
397 			cptr = sc->sc_cplane;
398 			while (--i >= 0)
399 				*cptr++ &= TCX_CTL_PIXELMASK;
400 		}
401 	}
402 #endif
403 	return (0);
404 }
405 
406 int
407 tcxioctl(dev_t dev, u_long cmd, void *data, int flags, struct lwp *l)
408 {
409 	struct tcx_softc *sc = device_lookup_private(&tcx_cd, minor(dev));
410 	int error;
411 
412 	switch (cmd) {
413 
414 	case FBIOGTYPE:
415 		*(struct fbtype *)data = sc->sc_fb.fb_type;
416 		break;
417 
418 	case FBIOGATTR:
419 #define fba ((struct fbgattr *)data)
420 		fba->real_type = sc->sc_fb.fb_type.fb_type;
421 		fba->owner = 0;		/* XXX ??? */
422 		fba->fbtype = sc->sc_fb.fb_type;
423 		fba->sattr.flags = 0;
424 		fba->sattr.emu_type = sc->sc_fb.fb_type.fb_type;
425 		fba->sattr.dev_specific[0] = -1;
426 		fba->emu_types[0] = sc->sc_fb.fb_type.fb_type;
427 		fba->emu_types[1] = FBTYPE_SUN3COLOR;
428 		fba->emu_types[2] = -1;
429 #undef fba
430 		break;
431 
432 	case FBIOGETCMAP:
433 #define	p ((struct fbcmap *)data)
434 		return (bt_getcmap(p, &sc->sc_cmap, 256, 1));
435 
436 	case FBIOPUTCMAP:
437 		/* copy to software map */
438 #ifdef TCX_CG8
439 		if (!sc->sc_8bit) {
440 			/*
441 			 * cg8 has extra bits in high-order byte of the index
442 			 * that bt_putcmap doesn't recognize
443 			 */
444 			p->index &= 0xffffff;
445 		}
446 #endif
447 		error = bt_putcmap(p, &sc->sc_cmap, 256, 1);
448 		if (error)
449 			return (error);
450 		/* now blast them into the chip */
451 		/* XXX should use retrace interrupt */
452 		tcx_loadcmap(sc, p->index, p->count);
453 #undef p
454 		break;
455 
456 	case FBIOGVIDEO:
457 		*(int *)data = sc->sc_blanked;
458 		break;
459 
460 	case FBIOSVIDEO:
461 		if (*(int *)data)
462 			tcx_unblank(&sc->sc_dev);
463 		else if (!sc->sc_blanked) {
464 			sc->sc_blanked = 1;
465 			sc->sc_thc->thc_hcmisc &= ~THC_MISC_VIDEN;
466 			/* Put monitor in `power-saving mode' */
467 			sc->sc_thc->thc_hcmisc |= THC_MISC_VSYNC_DISABLE;
468 			sc->sc_thc->thc_hcmisc |= THC_MISC_HSYNC_DISABLE;
469 		}
470 		break;
471 
472 	default:
473 #ifdef DEBUG
474 		log(LOG_NOTICE, "tcxioctl(0x%lx) (%s[%d])\n", cmd,
475 		    l->l_proc->p_comm, l->l_proc->p_pid);
476 #endif
477 		return (ENOTTY);
478 	}
479 	return (0);
480 }
481 
482 /*
483  * Clean up hardware state (e.g., after bootup or after X crashes).
484  */
485 static void
486 tcx_reset(struct tcx_softc *sc)
487 {
488 	volatile struct bt_regs *bt;
489 
490 	/* Enable cursor in Brooktree DAC. */
491 	bt = sc->sc_bt;
492 	bt->bt_addr = 0x06 << 24;
493 	bt->bt_ctrl |= 0x03 << 24;
494 }
495 
496 /*
497  * Load a subset of the current (new) colormap into the color DAC.
498  */
499 static void
500 tcx_loadcmap(struct tcx_softc *sc, int start, int ncolors)
501 {
502 	volatile struct bt_regs *bt;
503 	u_int *ip, i;
504 	int count;
505 
506 	ip = &sc->sc_cmap.cm_chip[BT_D4M3(start)];	/* start/4 * 3 */
507 	count = BT_D4M3(start + ncolors - 1) - BT_D4M3(start) + 3;
508 	bt = sc->sc_bt;
509 	bt->bt_addr = BT_D4M4(start) << 24;
510 	while (--count >= 0) {
511 		i = *ip++;
512 		/* hardware that makes one want to pound boards with hammers */
513 		bt->bt_cmap = i;
514 		bt->bt_cmap = i << 8;
515 		bt->bt_cmap = i << 16;
516 		bt->bt_cmap = i << 24;
517 	}
518 }
519 
520 static void
521 tcx_unblank(struct device *dev)
522 {
523 	struct tcx_softc *sc = device_private(dev);
524 
525 	if (sc->sc_blanked) {
526 		sc->sc_blanked = 0;
527 		sc->sc_thc->thc_hcmisc &= ~THC_MISC_VSYNC_DISABLE;
528 		sc->sc_thc->thc_hcmisc &= ~THC_MISC_HSYNC_DISABLE;
529 		sc->sc_thc->thc_hcmisc |= THC_MISC_VIDEN;
530 	}
531 }
532 
533 /*
534  * Base addresses at which users can mmap() the various pieces of a tcx.
535  */
536 #define	TCX_USER_RAM	0x00000000
537 #define	TCX_USER_RAM24	0x01000000
538 #define	TCX_USER_RAM_COMPAT	0x04000000	/* cg3 emulation */
539 #define	TCX_USER_STIP	0x10000000
540 #define	TCX_USER_BLIT	0x20000000
541 #define	TCX_USER_RDFB32	0x28000000
542 #define	TCX_USER_RSTIP	0x30000000
543 #define	TCX_USER_RBLIT	0x38000000
544 #define	TCX_USER_TEC	0x70001000
545 #define	TCX_USER_BTREGS	0x70002000
546 #define	TCX_USER_THC	0x70004000
547 #define	TCX_USER_DHC	0x70008000
548 #define	TCX_USER_ALT	0x7000a000
549 #define	TCX_USER_UART	0x7000c000
550 #define	TCX_USER_VRT	0x7000e000
551 #define	TCX_USER_ROM	0x70010000
552 
553 struct mmo {
554 	u_int	mo_uaddr;	/* user (virtual) address */
555 	u_int	mo_size;	/* size, or 0 for video ram size */
556 	u_int	mo_bank;	/* register bank number */
557 };
558 
559 /*
560  * Return the address that would map the given device at the given
561  * offset, allowing for the given protection, or return -1 for error.
562  *
563  * XXX	needs testing against `demanding' applications (e.g., aviator)
564  */
565 paddr_t
566 tcxmmap(dev_t dev, off_t off, int prot)
567 {
568 	struct tcx_softc *sc = device_lookup_private(&tcx_cd, minor(dev));
569 	struct openprom_addr *rr = sc->sc_physadr;
570 	struct mmo *mo, *mo_end;
571 	u_int u, sz;
572 	static struct mmo mmo[] = {
573 		{ TCX_USER_RAM, 0, TCX_REG_DFB8 },
574 		{ TCX_USER_RAM24, 0, TCX_REG_DFB24 },
575 		{ TCX_USER_RAM_COMPAT, 0, TCX_REG_DFB8 },
576 
577 		{ TCX_USER_STIP, 1, TCX_REG_STIP },
578 		{ TCX_USER_BLIT, 1, TCX_REG_BLIT },
579 		{ TCX_USER_RDFB32, 0, TCX_REG_RDFB32 },
580 		{ TCX_USER_RSTIP, 1, TCX_REG_RSTIP },
581 		{ TCX_USER_RBLIT, 1, TCX_REG_RBLIT },
582 		{ TCX_USER_TEC, 1, TCX_REG_TEC },
583 		{ TCX_USER_BTREGS, 8192 /* XXX */, TCX_REG_CMAP },
584 		{ TCX_USER_THC, sizeof(struct tcx_thc), TCX_REG_THC },
585 		{ TCX_USER_DHC, 1, TCX_REG_DHC },
586 		{ TCX_USER_ALT, 1, TCX_REG_ALT },
587 		{ TCX_USER_ROM, 65536, TCX_REG_ROM },
588 	};
589 #define NMMO (sizeof mmo / sizeof *mmo)
590 #ifdef TCX_CG8
591 	/*
592 	 * alternate mapping for CG8 emulation:
593 	 * map part of the 8-bit-deep framebuffer into the cg8 overlay
594 	 * space, just so there's something there, and map the 32-bit-deep
595 	 * framebuffer where cg8 users expect to find it.
596 	 */
597 	static struct mmo mmo_cg8[] = {
598 		{ TCX_USER_RAM, TCX_CG8OVERLAY, TCX_REG_DFB8 },
599 		{ TCX_CG8OVERLAY, TCX_SIZE_DFB32, TCX_REG_DFB24 },
600 		{ TCX_USER_RAM_COMPAT, TCX_SIZE_DFB32, TCX_REG_DFB24 }
601 	};
602 #define NMMO_CG8 (sizeof mmo_cg8 / sizeof *mmo_cg8)
603 #endif
604 
605 	if (off & PGOFSET)
606 		panic("tcxmmap");
607 
608 	/*
609 	 * Entries with size 0 map video RAM (i.e., the size in fb data).
610 	 * Entries that map 32-bit deep regions are adjusted for their
611 	 * depth (fb_size gives the size of the 8-bit-deep region).
612 	 *
613 	 * Since we work in pages, the fact that the map offset table's
614 	 * sizes are sometimes bizarre (e.g., 1) is effectively ignored:
615 	 * one byte is as good as one page.
616 	 */
617 #ifdef TCX_CG8
618 	if (sc->sc_8bit) {
619 		mo = mmo;
620 		mo_end = &mmo[NMMO];
621 	} else {
622 		mo = mmo_cg8;
623 		mo_end = &mmo_cg8[NMMO_CG8];
624 	}
625 #else
626 	mo = mmo;
627 	mo_end = &mmo[NMMO];
628 #endif
629 	for (; mo < mo_end; mo++) {
630 		if ((u_int)off < mo->mo_uaddr)
631 			continue;
632 		u = off - mo->mo_uaddr;
633 		sz = mo->mo_size;
634 		if (sz == 0) {
635 			sz = sc->sc_fb.fb_type.fb_size;
636 			/*
637 			 * check for the 32-bit-deep regions and adjust
638 			 * accordingly
639 			 */
640 			if (mo->mo_uaddr == TCX_USER_RAM24 ||
641 			    mo->mo_uaddr == TCX_USER_RDFB32) {
642 				if (sc->sc_8bit) {
643 					/*
644 					 * not present on 8-bit hardware
645 					 */
646 					continue;
647 				}
648 				sz *= 4;
649 			}
650 		}
651 		if (u < sz) {
652 			return (bus_space_mmap(sc->sc_bustag,
653 				BUS_ADDR(rr[mo->mo_bank].oa_space,
654 					 rr[mo->mo_bank].oa_base),
655 				u,
656 				prot,
657 				BUS_SPACE_MAP_LINEAR));
658 		}
659 	}
660 	return (-1);
661 }
662