xref: /haiku/src/add-ons/accelerants/matrox/Overlay.c (revision 5ac9b506412b11afb993bb52d161efe7666958a5)
1 /* Written by Rudolf Cornelissen 05-2002/11-2009 */
2 
3 /* Note on 'missing features' in BeOS 5.0.3 and DANO:
4  * BeOS needs to define more colorspaces! It would be nice if BeOS would support the FourCC 'definitions'
5  * of colorspaces. These colorspaces are 32bit words, so it could be simply done (or is it already so?)
6  */
7 
8 #define MODULE_BIT 0x00000400
9 
10 #include "acc_std.h"
11 
12 /* define the supported overlay input colorspaces */
13 /* Note:
14  * G200-G550 can all do YUV4:2:0 2-plane colorspace as well,
15  * G200 does not support RGB modes while > G200 do (but with limited scaling and without filtering),
16  * G200 does not support YUV4:2:0 3-plane mode while > G200 do.
17  * It would be nice to have the YUV4:2:0 2-plane mode implemented also later on, but the Be colorspace
18  * definitions (in GraphicsDefs.h, R5.0.3 and DANO5.1d0) do not include this one... */
19 static uint32 overlay_colorspaces [] = { (uint32)B_YCbCr422, (uint32)B_NO_COLOR_SPACE };
20 
21 uint32 OVERLAY_COUNT(const display_mode *dm)
22 // This method is never used AFAIK though it *is* exported on R5.0.3 and DANO.
23 // Does someone know howto invoke it?
24 {
25 	LOG(4,("Overlay: count called\n"));
26 
27 	/* check for NULL pointer */
28 	if (dm == NULL)
29 	{
30 		LOG(4,("Overlay: No display mode specified!\n"));
31 	}
32 	/* apparantly overlay count should report the number of 'overlay units' on the card */
33 	return 1;
34 }
35 
36 const uint32 *OVERLAY_SUPPORTED_SPACES(const display_mode *dm)
37 // This method is never used AFAIK though it *is* exported on R5.0.3 and DANO.
38 // Does someone know howto invoke it?
39 {
40 	LOG(4,("Overlay: supported_spaces called.\n"));
41 
42 	/* check for NULL pointer */
43 	if (dm == NULL)
44 	{
45 		LOG(4,("Overlay: No display mode specified!\n"));
46 		return NULL;
47 	}
48 
49 	/* interlaced VGA is not supported by G200-G550 BES */
50 	if (dm->timing.flags & B_TIMING_INTERLACED)
51 	{
52 		return NULL;
53 	}
54 	/* return a B_NO_COLOR_SPACE terminated list */
55 	return &overlay_colorspaces[0];
56 }
57 
58 uint32 OVERLAY_SUPPORTED_FEATURES(uint32 a_color_space)
59 // This method is never used AFAIK. On R5.0.3 and DANO it is not even exported!
60 {
61 	LOG(4,("Overlay: supported_features: color_space $%08x\n",a_color_space));
62 
63 	/* check what features (like the keying method) are supported on the current
64 	 * Desktop colorspace */
65 	//fixme? Or are we talking about the overlay input bitmap's colorspace?
66 	switch (a_color_space)
67 	{
68 	default:
69 			/* fixme: for now 'direct 32bit' desktop colorspace assumed */
70 			return
71 				( B_OVERLAY_KEYING_USES_ALPHA 	 |
72 				  B_OVERLAY_COLOR_KEY 			 |
73 				  B_OVERLAY_HORIZONTAL_FILTERING |
74 				  B_OVERLAY_VERTICAL_FILTERING );
75 	}
76 }
77 
78 
79 const overlay_buffer *ALLOCATE_OVERLAY_BUFFER(color_space cs, uint16 width, uint16 height)
80 {
81 	int offset = 0;					/* used to determine next buffer to create */
82 	uintptr_t adress, adress2, temp32;	/* used to calculate buffer adresses */
83 	uint32 oldsize = 0;				/* used to 'squeeze' new buffers between already existing ones */
84 	int cnt;						/* loopcounter */
85 
86 	/* acquire the shared benaphore */
87 	AQUIRE_BEN(si->overlay.lock)
88 
89 	LOG(4, ("Overlay: cardRAM_start = $%p\n", (uint8*)si->framebuffer));
90 	LOG(4, ("Overlay: cardRAM_start_DMA = $%p\n", (uint8*)si->framebuffer_pci));
91 	LOG(4, ("Overlay: cardRAM_size = %dMb\n", si->ps.memory_size));
92 
93 	/* find first empty slot (room for another buffer?) */
94 	for (offset = 0; offset < MAXBUFFERS; offset++)
95 	{
96 		if (si->overlay.myBuffer[offset].buffer == NULL) break;
97 	}
98 
99 	LOG(4, ("Overlay: Allocate_buffer offset = %d\n", offset));
100 
101 	if (offset < MAXBUFFERS)
102 	/* setup new scaler input buffer */
103 	{
104 		switch (cs)
105 		{
106 			case B_YCbCr422:
107 					/* check if slopspace is needed: compatible settings choosen for now:
108 					 * G200 can do with ~0x0003 while > G200 need ~x0007.
109 					 * Optimized settings for G200 could reduce CPU load a tiny little bit there... */
110 					/* fixme: update needed for DVDmax support to adhere to CRTC2 constraints:
111 					 * case display_mode == B_RGB16: multiple = 32
112 					 * case display_mode == B_RGB32: multiple = 16 */
113 					if (width == (width & ~0x0007))
114 					{
115 						si->overlay.myBuffer[offset].width = width;
116 					}
117 					else
118 					{
119 						si->overlay.myBuffer[offset].width = (width & ~0x0007) + 8;
120 					}
121 					si->overlay.myBuffer[offset].bytes_per_row = 2 * si->overlay.myBuffer[offset].width;
122 
123 					/* check if the requested horizontal pitch is supported:
124 					 * G200 max. pitch is 4092 pixels, > G200 max pitch is 4088 pixels for this colorspace.
125 					 * Compatible check done, has no downside consequences here. */
126 					if (si->overlay.myBuffer[offset].width > 4088)
127 					{
128 						LOG(4,("Overlay: Sorry, requested buffer pitch not supported, aborted\n"));
129 
130 						/* release the shared benaphore */
131 						RELEASE_BEN(si->overlay.lock)
132 
133 						return NULL;
134 					}
135 					break;
136 
137 //			case 0xffff://fixme: which one(s)?
138 					//fixme: 4:2:0 2-plane supported format, should be selected only if detected
139 					/* check if slopspace is needed: compatible settings choosen for now:
140 					 * G200 can do with ~0x0007 while > G200 need ~x001f.
141 					 * Optimized settings for G200 could reduce CPU load a tiny little bit there... */
142 /*					if (width == (width & ~0x001f))
143 					{
144 						si->overlay.myBuffer[offset].width = width;
145 					}
146 					else
147 					{
148 						si->overlay.myBuffer[offset].width = (width & ~0x001f) + 32;
149 					}
150 */					/* assuming Y-plane only bytes_per_row are requested here */
151 /*					si->overlay.myBuffer[offset].bytes_per_row = si->overlay.myBuffer[offset].width;
152 */
153 					/* check if the requested horizontal pitch is supported:
154 					 * G200 max. pitch is 4088 pixels, > G200 max pitch is 4064 pixels for this colorspace.
155 					 * Compatible check done, has no real downside consequences here. */
156 /*					if (si->overlay.myBuffer[offset].width > 4064)
157 					{
158 						LOG(4,("Overlay: Sorry, requested buffer pitch not supported, aborted\n");
159 */
160 						/* release the shared benaphore */
161 /*						RELEASE_BEN(si->overlay.lock)
162 
163 						return NULL;
164 					}
165 					break;
166 */
167 			default:
168 					/* unsupported colorspace! */
169 					LOG(4,("Overlay: Sorry, colorspace $%08x not supported, aborted\n",cs));
170 
171 					/* release the shared benaphore */
172 					RELEASE_BEN(si->overlay.lock)
173 
174 					return NULL;
175 					break;
176 		}
177 
178 		/* check if the requested buffer width is supported */
179 		if (si->ps.card_type < G450) {
180 			if (si->overlay.myBuffer[offset].width > 1024) {
181 				LOG(4,("Overlay: Sorry, requested buffer width not supported, aborted\n"));
182 
183 				/* release the shared benaphore */
184 				RELEASE_BEN(si->overlay.lock)
185 
186 				return NULL;
187 			}
188 
189 			/* check if the requested buffer height is supported */
190 			if (height > 1024) {
191 				LOG(4,("Overlay: Sorry, requested buffer height not supported, aborted\n"));
192 
193 				/* release the shared benaphore */
194 				RELEASE_BEN(si->overlay.lock)
195 
196 				return NULL;
197 			}
198 		} else {
199 			if (si->overlay.myBuffer[offset].width > 1920) {
200 				LOG(4,("Overlay: Sorry, requested buffer width not supported, aborted\n"));
201 
202 				/* release the shared benaphore */
203 				RELEASE_BEN(si->overlay.lock)
204 
205 				return NULL;
206 			}
207 
208 			/* check if the requested buffer height is supported */
209 			if (height > 1080) {
210 				LOG(4,("Overlay: Sorry, requested buffer height not supported, aborted\n"));
211 
212 				/* release the shared benaphore */
213 				RELEASE_BEN(si->overlay.lock)
214 
215 				return NULL;
216 			}
217 		}
218 
219 		/* store slopspace (in pixels) for each bitmap for use by 'overlay unit' (BES) */
220 		si->overlay.myBufInfo[offset].slopspace = si->overlay.myBuffer[offset].width - width;
221 
222 		si->overlay.myBuffer[offset].space = cs;
223 		si->overlay.myBuffer[offset].height = height;
224 
225 		/* we define the overlay buffers to reside 'in the back' of the cards RAM */
226 		/* NOTE to app programmers:
227 		 * Beware that an app using overlay needs to track workspace switches and screenprefs
228 		 * changes. If such an action is detected, the app needs to reset it's pointers to the
229 		 * newly created overlay bitmaps, which will be assigned by BeOS automatically after such
230 		 * an event. (Also the app needs to respect the new overlay_constraints that will be applicable!)
231 		 *
232 		 * It is entirely possible that new bitmaps may *not* be re-setup at all, or less of them
233 		 * than previously setup by the app might be re-setup. This is due to cardRAM restraints then.
234 		 * This means that the app should also check for NULL pointers returned by the bitmaps,
235 		 * and if this happens, it needs to fallback to single buffered overlay or even fallback to
236 		 * bitmap output for the new situation. */
237 
238 		/* Another NOTE for app programmers:
239 		 * A *positive* side-effect of assigning the first overlay buffer exactly at the end of the
240 		 * cardRAM is that apps that try to write beyond the buffer's space get a segfault immediately.
241 		 * This *greatly* simplifies tracking such errors!
242 		 * Of course such errors may lead to strange effects in the app or driver behaviour if they are
243 		 * not hunted down and removed.. */
244 
245 		/* calculate first free RAM adress in card:
246 		 * Driver setup is as follows:
247 		 * card base: 		- hardware cursor bitmap (if used),
248 		 * directly above	- screen memory for both heads */
249 		adress2 = (((uintptr_t)((uint8*)si->fbc.frame_buffer)) +	/* cursor already included here */
250 			(si->fbc.bytes_per_row * si->dm.virtual_height));	/* size in bytes of screen(s) */
251 		LOG(4, ("Overlay: first free cardRAM virtual adress $%08x\n", adress2));
252 
253 		/* calculate 'preliminary' buffer size including slopspace */
254 		oldsize = si->overlay.myBufInfo[offset].size;
255 		si->overlay.myBufInfo[offset].size
256 			= si->overlay.myBuffer[offset].bytes_per_row * si->overlay.myBuffer[offset].height;
257 
258 		/* calculate virtual memory adress that would be needed for a new bitmap */
259 		/* NOTE to app programmers:
260 		 * For testing app behaviour regarding workspace switches or screen prefs changes to settings
261 		 * that do not have enough cardRAM left for allocation of overlay bitmaps, you need a card with
262 		 * a low amount of RAM. Or you can set in the file matrox.settings for example:
263 		 * memory 8 #8Mb RAM on card
264 		 * and reboot (this simulates 8Mb RAM on the card).
265 		 *
266 		 * If you switch now to settings: 1600x1200x32bit (single head) the app needs to fallback to
267 		 * bitmap output or maybe single buffered overlay output if small bitmaps are used. */
268 
269 		adress = (((uintptr_t)((uint8*)si->framebuffer)) + (si->ps.memory_size * 1024 * 1024));
270 		for (cnt = 0; cnt <= offset; cnt++)
271 		{
272 			adress -= si->overlay.myBufInfo[cnt].size;
273 		}
274 
275 		/* the > G200 scalers require buffers to be aligned to 16 byte pages cardRAM offset, G200 can do with
276 		 * 8 byte pages cardRAM offset. Compatible settings used, has no real downside consequences here */
277 
278 		/* Check if we need to modify the buffers starting adress and thus the size */
279 		/* calculate 'would be' cardRAM offset */
280 		temp32 = (adress - ((uintptr_t)((vuint32 *)si->framebuffer)));
281 		/* check if it is aligned */
282 		if (temp32 != (temp32 & 0xfffffff0))
283 		{
284 			/* update the (already calculated) buffersize to get it aligned */
285 			si->overlay.myBufInfo[offset].size += (temp32 - (temp32 & 0xfffffff0));
286 			/* update the (already calculated) adress to get it aligned */
287 			adress -= (temp32 - (temp32 & 0xfffffff0));
288 		}
289 		LOG(4,("Overlay: new buffer needs virtual adress $%08x\n", adress));
290 
291 		/* First check now if buffer to be defined is 'last one' in memory (speaking backwards):
292 		 * this is done to prevent a large buffer getting created in the space a small buffer
293 		 * occupied earlier, if not all buffers created were deleted.
294 		 * Note also that the app can delete the buffers in any order desired. */
295 
296 		/* NOTE to app programmers:
297 		 * If you are going to delete a overlay buffer you created, you should delete them *all* and
298 		 * then re-create only the new ones needed. This way you are sure not to get unused memory-
299 		 * space in between your overlay buffers for instance, so cardRAM is used 'to the max'.
300 		 * If you don't, you might not get a buffer at all if you are trying to set up a larger one
301 		 * than before.
302 		 * (Indeed: not all buffers *have* to be of the same type and size...) */
303 
304 		for (cnt = offset; cnt < MAXBUFFERS; cnt++)
305 		{
306 			if (si->overlay.myBuffer[cnt].buffer != NULL)
307 			{
308 				/* Check if the new buffer would fit into the space the single old one used here */
309 				if (si->overlay.myBufInfo[offset].size <= oldsize)
310 				{
311 					/* It does, so we reset to the old size and adresses to prevent the space from shrinking
312 					 * if we get here again... */
313 					adress -= (oldsize - si->overlay.myBufInfo[offset].size);
314 					si->overlay.myBufInfo[offset].size = oldsize;
315 					LOG(4,("Overlay: 'squeezing' in buffer:\n"
316 						   "Overlay: resetting it to virtual adress $%08x and size $%08x\n", adress,oldsize));
317 					/* force exiting the FOR loop */
318 					cnt = MAXBUFFERS;
319 				}
320 				else
321 				{
322 					/* nogo, sorry */
323 					LOG(4,("Overlay: Other buffer(s) exist after this one:\n"
324 						   "Overlay: not enough space to 'squeeze' this one in, aborted\n"));
325 
326 					/* Reset to the old size to prevent the space from 'growing' if we get here again... */
327 					si->overlay.myBufInfo[offset].size = oldsize;
328 
329 					/* release the shared benaphore */
330 					RELEASE_BEN(si->overlay.lock)
331 
332 					return NULL;
333 				}
334 			}
335 		}
336 
337 		/* check if we have enough space to setup this new bitmap
338 		 * (preventing overlap of desktop RAMspace & overlay bitmap RAMspace here) */
339 		if (adress < adress2)
340 		/* nope, sorry */
341 		{
342 			LOG(4,("Overlay: Sorry, no more space for buffers: aborted\n"));
343 
344 			/* release the shared benaphore */
345 			RELEASE_BEN(si->overlay.lock)
346 
347 			return NULL;
348 		}
349 		/* continue buffer setup */
350 		si->overlay.myBuffer[offset].buffer = (void *) adress;
351 
352 		/* calculate physical memory adress (for dma use) */
353 		/* NOTE to app programmers:
354 		 * For testing app behaviour regarding workspace switches or screen prefs changes to settings
355 		 * that do not have enough cardRAM left for allocation of overlay bitmaps, you need a card with
356 		 * a low amount of RAM. Or you can set in the file matrox.settings for example:
357 		 * memory 8 #8Mb RAM on card
358 		 * and reboot (this simulates 8Mb RAM on the card).
359 		 *
360 		 * If you switch now to settings: 1600x1200x32bit (single head) the app needs to fallback to
361 		 * bitmap output or maybe single buffered overlay output if small bitmaps are used. */
362 
363 		adress = (((uintptr_t)((uint8*)si->framebuffer_pci)) + (si->ps.memory_size * 1024 * 1024));
364 		for (cnt = 0; cnt <= offset; cnt++)
365 		{
366 			adress -= si->overlay.myBufInfo[cnt].size;
367 		}
368 		/* this adress is already aligned to the scaler's requirements (via the already modified sizes) */
369 		si->overlay.myBuffer[offset].buffer_dma = (void *) adress;
370 
371 		LOG(4, ("Overlay: New buffer: addr $%p, dma_addr $%p, color space $%08x\n",
372 			(uint8*)si->overlay.myBuffer[offset].buffer,
373 			(uint8*)si->overlay.myBuffer[offset].buffer_dma, cs));
374 		LOG(4, ("Overlay: New buffer's size is $%08x\n", si->overlay.myBufInfo[offset].size));
375 
376 		/* release the shared benaphore */
377 		RELEASE_BEN(si->overlay.lock)
378 
379 		return &si->overlay.myBuffer[offset];
380 	} else {
381 		/* sorry, no more room for buffers */
382 		LOG(4, ("Overlay: Sorry, no more space for buffers: aborted\n"));
383 
384 		/* release the shared benaphore */
385 		RELEASE_BEN(si->overlay.lock)
386 
387 		return NULL;
388 	}
389 }
390 
391 
392 status_t RELEASE_OVERLAY_BUFFER(const overlay_buffer *ob)
393 /* Note that the user can delete the buffers in any order desired! */
394 {
395 	int offset = 0;
396 
397 	if (ob != NULL)
398 	{
399 		/* find the buffer */
400 		for (offset = 0; offset < MAXBUFFERS; offset++)
401 		{
402 			if (si->overlay.myBuffer[offset].buffer == ob->buffer) break;
403 		}
404 
405 		if (offset < MAXBUFFERS)
406 		/* delete current buffer */
407 		{
408 			si->overlay.myBuffer[offset].buffer = NULL;
409 			si->overlay.myBuffer[offset].buffer_dma = NULL;
410 
411 			LOG(4,("Overlay: Release_buffer offset = %d, buffer released\n",offset));
412 
413 			return B_OK;
414 		}
415 		else
416 		{
417 			/* this is no buffer of ours! */
418 			LOG(4,("Overlay: Release_overlay_buffer: not ours, aborted!\n"));
419 
420 			return B_ERROR;
421 		}
422 	}
423 	else
424 	/* no buffer specified! */
425 	{
426 		LOG(4,("Overlay: Release_overlay_buffer: no buffer specified, aborted!\n"));
427 
428 		return B_ERROR;
429 	}
430 }
431 
432 status_t GET_OVERLAY_CONSTRAINTS
433 	(const display_mode *dm, const overlay_buffer *ob, overlay_constraints *oc)
434 {
435 	int offset = 0;
436 
437 	LOG(4,("Overlay: Get_overlay_constraints called\n"));
438 
439 	/* check for NULL pointers */
440 	if ((dm == NULL) || (ob == NULL) || (oc == NULL))
441 	{
442 		LOG(4,("Overlay: Get_overlay_constraints: Null pointer(s) detected!\n"));
443 		return B_ERROR;
444 	}
445 
446 	/* find the buffer */
447 	for (offset = 0; offset < MAXBUFFERS; offset++)
448 	{
449 		if (si->overlay.myBuffer[offset].buffer == ob->buffer) break;
450 	}
451 
452 	if (offset < MAXBUFFERS)
453 	{
454 		/* scaler input (values are in pixels) */
455 		oc->view.h_alignment = 0;
456 		oc->view.v_alignment = 0;
457 
458 		switch (ob->space)
459 		{
460 			case B_YCbCr422:
461 					/* G200 can work with 3, > G200 need 7. Compatible setting returned for now.
462 					 * Note: this has to be in sync with the slopspace setup during buffer allocation.. */
463 					oc->view.width_alignment = 7;
464 					break;
465 
466 //			case 0xffff://fixme: which one(s)? (4:2:0 supported formats. Not yet used...)
467 					/* G200 can work with 7, > G200 need 31. Compatible setting returned for now.
468 					 * Note: this has to be in sync with the slopspace setup during buffer allocation.. */
469 /*					oc->view.width_alignment = 31;
470 					break;
471 */
472 			default:
473 					/* we should not be here, but set the worst-case value just to be safe anyway */
474 					oc->view.width_alignment = 31;
475 					break;
476 		}
477 
478 		oc->view.height_alignment = 0;
479 		oc->view.width.min = 1;
480 		oc->view.height.min = 2; /* two fields */
481 		oc->view.width.max = ob->width;
482 		oc->view.height.max = ob->height;
483 
484 		/* scaler output restrictions */
485 		oc->window.h_alignment = 0;
486 		oc->window.v_alignment = 0;
487 		oc->window.width_alignment = 0;
488 		oc->window.height_alignment = 0;
489 		oc->window.width.min = 2;
490 		/* G200-G550 can output upto and including 2048 pixels in width */
491 		if (dm->virtual_width > 2048)
492 		{
493 			oc->window.width.max = 2048;
494 		}
495 		else
496 		{
497 			oc->window.width.max = dm->virtual_width;
498 		}
499 		oc->window.height.min = 2;
500 		/* G200-G550 can output upto and including 2048 pixels in height */
501 		if (dm->virtual_height > 2048)
502 		{
503 			oc->window.height.max = 2048;
504 		}
505 		else
506 		{
507 			oc->window.height.max = dm->virtual_height;
508 		}
509 
510 		/* G200-G550 scaling restrictions */
511 		/* Adjust horizontal restrictions if pixelclock is above BES max. speed! */
512 		/* Note: If RGB32 is implemented no scaling is supported! */
513 		if (si->dm.timing.pixel_clock > BESMAXSPEED)
514 		{
515 			oc->h_scale.min = (1 * 2) / (32 - (1 / (float)16384));
516 			oc->h_scale.max = (16384 * 2)/(float)(ob->width - si->overlay.myBufInfo[offset].slopspace);
517 		}
518 		else
519 		{
520 			oc->h_scale.min = 1 / (32 - (1 / (float)16384));
521 			oc->h_scale.max = 16384/(float)(ob->width - si->overlay.myBufInfo[offset].slopspace);
522 		}
523 		oc->v_scale.min = 1 / (32 - (1 / (float)16384));
524 		oc->v_scale.max = 16384/(float)ob->height;
525 
526 		return B_OK;
527 	}
528 	else
529 	{
530 		/* this is no buffer of ours! */
531 		LOG(4,("Overlay: Get_overlay_constraints: buffer is not ours, aborted!\n"));
532 
533 		return B_ERROR;
534 	}
535 }
536 
537 overlay_token ALLOCATE_OVERLAY(void)
538 {
539 	uint32 tmpToken;
540 	LOG(4,("Overlay: Allocate_overlay called: "));
541 
542 	/* come up with a token */
543 	tmpToken = 0x12345678;
544 
545 	/* acquire the shared benaphore */
546 	AQUIRE_BEN(si->overlay.lock)
547 
548 	/* overlay unit already in use? */
549 	if (si->overlay.myToken == NULL)
550 	/* overlay unit is available */
551 	{
552 		LOG(4,("succesfull\n"));
553 
554 		si->overlay.myToken = &tmpToken;
555 
556 		/* release the shared benaphore */
557 		RELEASE_BEN(si->overlay.lock)
558 
559 		return si->overlay.myToken;
560 	}
561 	else
562 	/* sorry, overlay unit is occupied */
563 	{
564 		LOG(4,("failed: already in use!\n"));
565 
566 		/* release the shared benaphore */
567 		RELEASE_BEN(si->overlay.lock)
568 
569 		return NULL;
570 	}
571 }
572 
573 status_t RELEASE_OVERLAY(overlay_token ot)
574 {
575 	LOG(4,("Overlay: Release_overlay called: "));
576 
577 	/* is this call for real? */
578 	if ((ot == NULL) || (si->overlay.myToken == NULL) || (ot != si->overlay.myToken))
579 	/* nope, abort */
580 	{
581 		LOG(4,("failed, not in use!\n"));
582 
583 		return B_ERROR;
584 	}
585 	else
586 	/* call is for real */
587 	{
588 
589 		gx00_release_bes();
590 
591 		LOG(4,("succesfull\n"));
592 
593 		si->overlay.myToken = NULL;
594 		return B_OK;
595 	}
596 }
597 
598 status_t CONFIGURE_OVERLAY
599 	(overlay_token ot, const overlay_buffer *ob, const overlay_window *ow, const overlay_view *ov)
600 {
601 	int offset = 0; /* used for buffer index */
602 
603 	LOG(4,("Overlay: Configure_overlay called: "));
604 
605 	/* Note:
606 	 * When a Workspace switch, screen prefs change, or overlay app shutdown occurs, BeOS will
607 	 * release all overlay buffers. The buffer currently displayed at that moment, may need some
608 	 * 'hardware releasing' in the CONFIGURE_OVERLAY routine. This is why CONFIGURE_OVERLAY gets
609 	 * called one more time then, with a null pointer for overlay_window and overlay_view, while
610 	 * the currently displayed overlay_buffer is given.
611 	 * The G200-G550 do not need to do anything on such an occasion, so we simply return if we
612 	 * get called then. */
613 	if ((ow == NULL) || (ov == NULL))
614 	{
615 		LOG(4,("output properties changed\n"));
616 
617 		return B_OK;
618 	}
619 
620 	/* Note:
621 	 * If during overlay use the screen prefs are changed, or the workspace has changed, it
622 	 * may be that we were not able to re-allocate the requested overlay buffers (or only partly)
623 	 * due to lack of cardRAM. If the app does not respond properly to this, we might end up
624 	 * with a NULL pointer instead of a overlay_buffer to work with here.
625 	 * Of course, we need to abort then to prevent the system from 'going down'.
626 	 * The app will probably crash because it will want to write into this non-existant buffer
627 	 * at some point. */
628 	if (ob == NULL)
629 	{
630 		LOG(4,("no overlay buffer specified\n"));
631 
632 		return B_ERROR;
633 	}
634 
635 	/* is this call done by the app that owns us? */
636 	if ((ot == NULL) || (si->overlay.myToken == NULL) || (ot != si->overlay.myToken))
637 	/* nope, abort */
638 	{
639 		LOG(4,("failed\n"));
640 
641 		return B_ERROR;
642 	}
643 	else
644 	/* call is for real */
645 	{
646 		/* find the buffer's offset */
647 		for (offset = 0; offset < MAXBUFFERS; offset++)
648 		{
649 			if (si->overlay.myBuffer[offset].buffer == ob->buffer) break;
650 		}
651 
652 		if (offset < MAXBUFFERS)
653 		{
654 			LOG(4,("succesfull, switching to buffer %d\n", offset));
655 
656 			gx00_configure_bes(ob, ow, ov, offset);
657 
658 			return B_OK;
659 		}
660 		else
661 		{
662 			/* this is no buffer of ours! */
663 			LOG(4,("buffer is not ours, aborted!\n"));
664 
665 			return B_ERROR;
666 		}
667 	}
668 }
669