xref: /linux/drivers/video/fbdev/matrox/matroxfb_crtc2.c (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  * Hardware accelerated Matrox Millennium I, II, Mystique, G100, G200, G400 and G450.
5  *
6  * (c) 1998-2002 Petr Vandrovec <vandrove@vc.cvut.cz>
7  *
8  * Portions Copyright (c) 2001 Matrox Graphics Inc.
9  *
10  * Version: 1.65 2002/08/14
11  *
12  */
13 
14 #include "matroxfb_maven.h"
15 #include "matroxfb_crtc2.h"
16 #include "matroxfb_misc.h"
17 #include "matroxfb_DAC1064.h"
18 #include <linux/matroxfb.h>
19 #include <linux/slab.h>
20 #include <linux/uaccess.h>
21 
22 /* **************************************************** */
23 
24 static int mem = 8192;
25 
26 module_param(mem, int, 0);
27 MODULE_PARM_DESC(mem, "Memory size reserved for dualhead (default=8MB)");
28 
29 /* **************************************************** */
30 
31 static int matroxfb_dh_setcolreg(unsigned regno, unsigned red, unsigned green,
32 		unsigned blue, unsigned transp, struct fb_info* info) {
33 	u_int32_t col;
34 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
35 
36 	if (regno >= 16)
37 		return 1;
38 	if (m2info->fbcon.var.grayscale) {
39 		/* gray = 0.30*R + 0.59*G + 0.11*B */
40 		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
41 	}
42 	red = CNVT_TOHW(red, m2info->fbcon.var.red.length);
43 	green = CNVT_TOHW(green, m2info->fbcon.var.green.length);
44 	blue = CNVT_TOHW(blue, m2info->fbcon.var.blue.length);
45 	transp = CNVT_TOHW(transp, m2info->fbcon.var.transp.length);
46 
47 	col = (red << m2info->fbcon.var.red.offset)     |
48 	      (green << m2info->fbcon.var.green.offset) |
49 	      (blue << m2info->fbcon.var.blue.offset)   |
50 	      (transp << m2info->fbcon.var.transp.offset);
51 
52 	switch (m2info->fbcon.var.bits_per_pixel) {
53 		case 16:
54 			m2info->cmap[regno] = col | (col << 16);
55 			break;
56 		case 32:
57 			m2info->cmap[regno] = col;
58 			break;
59 	}
60 	return 0;
61 #undef m2info
62 }
63 
64 static void matroxfb_dh_restore(struct matroxfb_dh_fb_info* m2info,
65 		struct my_timming* mt,
66 		int mode,
67 		unsigned int pos) {
68 	u_int32_t tmp;
69 	u_int32_t datactl;
70 	struct matrox_fb_info *minfo = m2info->primary_dev;
71 
72 	switch (mode) {
73 		case 15:
74 			tmp = 0x00200000;
75 			break;
76 		case 16:
77 			tmp = 0x00400000;
78 			break;
79 /*		case 32: */
80 		default:
81 			tmp = 0x00800000;
82 			break;
83 	}
84 	tmp |= 0x00000001;	/* enable CRTC2 */
85 	datactl = 0;
86 	if (minfo->outputs[1].src == MATROXFB_SRC_CRTC2) {
87 		if (minfo->devflags.g450dac) {
88 			tmp |= 0x00000006; /* source from secondary pixel PLL */
89 			/* no vidrst when in monitor mode */
90 			if (minfo->outputs[1].mode != MATROXFB_OUTPUT_MODE_MONITOR) {
91 				tmp |=  0xC0001000; /* Enable H/V vidrst */
92 			}
93 		} else {
94 			tmp |= 0x00000002; /* source from VDOCLK */
95 			tmp |= 0xC0000000; /* enable vvidrst & hvidrst */
96 			/* MGA TVO is our clock source */
97 		}
98 	} else if (minfo->outputs[0].src == MATROXFB_SRC_CRTC2) {
99 		tmp |= 0x00000004; /* source from pixclock */
100 		/* PIXPLL is our clock source */
101 	}
102 	if (minfo->outputs[0].src == MATROXFB_SRC_CRTC2) {
103 		tmp |= 0x00100000;	/* connect CRTC2 to DAC */
104 	}
105 	if (mt->interlaced) {
106 		tmp |= 0x02000000;	/* interlaced, second field is bigger, as G450 apparently ignores it */
107 		mt->VDisplay >>= 1;
108 		mt->VSyncStart >>= 1;
109 		mt->VSyncEnd >>= 1;
110 		mt->VTotal >>= 1;
111 	}
112 	if ((mt->HTotal & 7) == 2) {
113 		datactl |= 0x00000010;
114 		mt->HTotal &= ~7;
115 	}
116 	tmp |= 0x10000000;	/* 0x10000000 is VIDRST polarity */
117 	mga_outl(0x3C14, ((mt->HDisplay - 8) << 16) | (mt->HTotal - 8));
118 	mga_outl(0x3C18, ((mt->HSyncEnd - 8) << 16) | (mt->HSyncStart - 8));
119 	mga_outl(0x3C1C, ((mt->VDisplay - 1) << 16) | (mt->VTotal - 1));
120 	mga_outl(0x3C20, ((mt->VSyncEnd - 1) << 16) | (mt->VSyncStart - 1));
121 	mga_outl(0x3C24, ((mt->VSyncStart) << 16) | (mt->HSyncStart));	/* preload */
122 	{
123 		u_int32_t linelen = m2info->fbcon.var.xres_virtual * (m2info->fbcon.var.bits_per_pixel >> 3);
124 		if (tmp & 0x02000000) {
125 			/* field #0 is smaller, so... */
126 			mga_outl(0x3C2C, pos);			/* field #1 vmemory start */
127 			mga_outl(0x3C28, pos + linelen);	/* field #0 vmemory start */
128 			linelen <<= 1;
129 			m2info->interlaced = 1;
130 		} else {
131 			mga_outl(0x3C28, pos);		/* vmemory start */
132 			m2info->interlaced = 0;
133 		}
134 		mga_outl(0x3C40, linelen);
135 	}
136 	mga_outl(0x3C4C, datactl);	/* data control */
137 	if (tmp & 0x02000000) {
138 		int i;
139 
140 		mga_outl(0x3C10, tmp & ~0x02000000);
141 		for (i = 0; i < 2; i++) {
142 			unsigned int nl;
143 			unsigned int lastl = 0;
144 
145 			while ((nl = mga_inl(0x3C48) & 0xFFF) >= lastl) {
146 				lastl = nl;
147 			}
148 		}
149 	}
150 	mga_outl(0x3C10, tmp);
151 	minfo->hw.crtc2.ctl = tmp;
152 
153 	tmp = mt->VDisplay << 16;	/* line compare */
154 	if (mt->sync & FB_SYNC_HOR_HIGH_ACT)
155 		tmp |= 0x00000100;
156 	if (mt->sync & FB_SYNC_VERT_HIGH_ACT)
157 		tmp |= 0x00000200;
158 	mga_outl(0x3C44, tmp);
159 }
160 
161 static void matroxfb_dh_disable(struct matroxfb_dh_fb_info* m2info) {
162 	struct matrox_fb_info *minfo = m2info->primary_dev;
163 
164 	mga_outl(0x3C10, 0x00000004);	/* disable CRTC2, CRTC1->DAC1, PLL as clock source */
165 	minfo->hw.crtc2.ctl = 0x00000004;
166 }
167 
168 static void matroxfb_dh_pan_var(struct matroxfb_dh_fb_info* m2info,
169 		struct fb_var_screeninfo* var) {
170 	unsigned int pos;
171 	unsigned int linelen;
172 	unsigned int pixelsize;
173 	struct matrox_fb_info *minfo = m2info->primary_dev;
174 
175 	m2info->fbcon.var.xoffset = var->xoffset;
176 	m2info->fbcon.var.yoffset = var->yoffset;
177 	pixelsize = m2info->fbcon.var.bits_per_pixel >> 3;
178 	linelen = m2info->fbcon.var.xres_virtual * pixelsize;
179 	pos = m2info->fbcon.var.yoffset * linelen + m2info->fbcon.var.xoffset * pixelsize;
180 	pos += m2info->video.offbase;
181 	if (m2info->interlaced) {
182 		mga_outl(0x3C2C, pos);
183 		mga_outl(0x3C28, pos + linelen);
184 	} else {
185 		mga_outl(0x3C28, pos);
186 	}
187 }
188 
189 static int matroxfb_dh_decode_var(struct matroxfb_dh_fb_info* m2info,
190 		struct fb_var_screeninfo* var,
191 		int *visual,
192 		int *video_cmap_len,
193 		int *mode) {
194 	unsigned int mask;
195 	unsigned int memlen;
196 	unsigned int vramlen;
197 
198 	switch (var->bits_per_pixel) {
199 		case 16:	mask = 0x1F;
200 				break;
201 		case 32:	mask = 0x0F;
202 				break;
203 		default:	return -EINVAL;
204 	}
205 	vramlen = m2info->video.len_usable;
206 	if (var->yres_virtual < var->yres)
207 		var->yres_virtual = var->yres;
208 	if (var->xres_virtual < var->xres)
209 		var->xres_virtual = var->xres;
210 	var->xres_virtual = (var->xres_virtual + mask) & ~mask;
211 	if (var->yres_virtual > 32767)
212 		return -EINVAL;
213 	memlen = var->xres_virtual * var->yres_virtual * (var->bits_per_pixel >> 3);
214 	if (memlen > vramlen)
215 		return -EINVAL;
216 	if (var->xoffset + var->xres > var->xres_virtual)
217 		var->xoffset = var->xres_virtual - var->xres;
218 	if (var->yoffset + var->yres > var->yres_virtual)
219 		var->yoffset = var->yres_virtual - var->yres;
220 
221 	var->xres &= ~7;
222 	var->left_margin &= ~7;
223 	var->right_margin &= ~7;
224 	var->hsync_len &= ~7;
225 
226 	*mode = var->bits_per_pixel;
227 	if (var->bits_per_pixel == 16) {
228 		if (var->green.length == 5) {
229 			var->red.offset = 10;
230 			var->red.length = 5;
231 			var->green.offset = 5;
232 			var->green.length = 5;
233 			var->blue.offset = 0;
234 			var->blue.length = 5;
235 			var->transp.offset = 15;
236 			var->transp.length = 1;
237 			*mode = 15;
238 		} else {
239 			var->red.offset = 11;
240 			var->red.length = 5;
241 			var->green.offset = 5;
242 			var->green.length = 6;
243 			var->blue.offset = 0;
244 			var->blue.length = 5;
245 			var->transp.offset = 0;
246 			var->transp.length = 0;
247 		}
248 	} else {
249 			var->red.offset = 16;
250 			var->red.length = 8;
251 			var->green.offset = 8;
252 			var->green.length = 8;
253 			var->blue.offset = 0;
254 			var->blue.length = 8;
255 			var->transp.offset = 24;
256 			var->transp.length = 8;
257 	}
258 	*visual = FB_VISUAL_TRUECOLOR;
259 	*video_cmap_len = 16;
260 	return 0;
261 }
262 
263 static int matroxfb_dh_open(struct fb_info* info, int user) {
264 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
265 	struct matrox_fb_info *minfo = m2info->primary_dev;
266 
267 	if (minfo) {
268 		int err;
269 
270 		if (minfo->dead) {
271 			return -ENXIO;
272 		}
273 		err = minfo->fbops.fb_open(&minfo->fbcon, user);
274 		if (err) {
275 			return err;
276 		}
277 	}
278 	return 0;
279 #undef m2info
280 }
281 
282 static int matroxfb_dh_release(struct fb_info* info, int user) {
283 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
284 	int err = 0;
285 	struct matrox_fb_info *minfo = m2info->primary_dev;
286 
287 	if (minfo) {
288 		err = minfo->fbops.fb_release(&minfo->fbcon, user);
289 	}
290 	return err;
291 #undef m2info
292 }
293 
294 /*
295  * This function is called before the register_framebuffer so
296  * no locking is needed.
297  */
298 static void matroxfb_dh_init_fix(struct matroxfb_dh_fb_info *m2info)
299 {
300 	struct fb_fix_screeninfo *fix = &m2info->fbcon.fix;
301 
302 	strcpy(fix->id, "MATROX DH");
303 
304 	fix->smem_start = m2info->video.base;
305 	fix->smem_len = m2info->video.len_usable;
306 	fix->ypanstep = 1;
307 	fix->ywrapstep = 0;
308 	fix->xpanstep = 8;	/* TBD */
309 	fix->mmio_start = m2info->mmio.base;
310 	fix->mmio_len = m2info->mmio.len;
311 	fix->accel = 0;		/* no accel... */
312 }
313 
314 static int matroxfb_dh_check_var(struct fb_var_screeninfo* var, struct fb_info* info) {
315 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
316 	int visual;
317 	int cmap_len;
318 	int mode;
319 
320 	return matroxfb_dh_decode_var(m2info, var, &visual, &cmap_len, &mode);
321 #undef m2info
322 }
323 
324 static int matroxfb_dh_set_par(struct fb_info* info) {
325 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
326 	int visual;
327 	int cmap_len;
328 	int mode;
329 	int err;
330 	struct fb_var_screeninfo* var = &info->var;
331 	struct matrox_fb_info *minfo = m2info->primary_dev;
332 
333 	if ((err = matroxfb_dh_decode_var(m2info, var, &visual, &cmap_len, &mode)) != 0)
334 		return err;
335 	/* cmap */
336 	{
337 		m2info->fbcon.screen_base = vaddr_va(m2info->video.vbase);
338 		m2info->fbcon.fix.visual = visual;
339 		m2info->fbcon.fix.type = FB_TYPE_PACKED_PIXELS;
340 		m2info->fbcon.fix.type_aux = 0;
341 		m2info->fbcon.fix.line_length = (var->xres_virtual * var->bits_per_pixel) >> 3;
342 	}
343 	{
344 		struct my_timming mt;
345 		unsigned int pos;
346 		int out;
347 		int cnt;
348 
349 		matroxfb_var2my(&m2info->fbcon.var, &mt);
350 		mt.crtc = MATROXFB_SRC_CRTC2;
351 		/* CRTC2 delay */
352 		mt.delay = 34;
353 
354 		pos = (m2info->fbcon.var.yoffset * m2info->fbcon.var.xres_virtual + m2info->fbcon.var.xoffset) * m2info->fbcon.var.bits_per_pixel >> 3;
355 		pos += m2info->video.offbase;
356 		cnt = 0;
357 		down_read(&minfo->altout.lock);
358 		for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
359 			if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2) {
360 				cnt++;
361 				if (minfo->outputs[out].output->compute) {
362 					minfo->outputs[out].output->compute(minfo->outputs[out].data, &mt);
363 				}
364 			}
365 		}
366 		minfo->crtc2.pixclock = mt.pixclock;
367 		minfo->crtc2.mnp = mt.mnp;
368 		up_read(&minfo->altout.lock);
369 		if (cnt) {
370 			matroxfb_dh_restore(m2info, &mt, mode, pos);
371 		} else {
372 			matroxfb_dh_disable(m2info);
373 		}
374 		DAC1064_global_init(minfo);
375 		DAC1064_global_restore(minfo);
376 		down_read(&minfo->altout.lock);
377 		for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
378 			if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2 &&
379 			    minfo->outputs[out].output->program) {
380 				minfo->outputs[out].output->program(minfo->outputs[out].data);
381 			}
382 		}
383 		for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
384 			if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2 &&
385 			    minfo->outputs[out].output->start) {
386 				minfo->outputs[out].output->start(minfo->outputs[out].data);
387 			}
388 		}
389 		up_read(&minfo->altout.lock);
390 	}
391 	m2info->initialized = 1;
392 	return 0;
393 #undef m2info
394 }
395 
396 static int matroxfb_dh_pan_display(struct fb_var_screeninfo* var, struct fb_info* info) {
397 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
398 	matroxfb_dh_pan_var(m2info, var);
399 	return 0;
400 #undef m2info
401 }
402 
403 static int matroxfb_dh_get_vblank(const struct matroxfb_dh_fb_info* m2info, struct fb_vblank* vblank) {
404 	struct matrox_fb_info *minfo = m2info->primary_dev;
405 
406 	matroxfb_enable_irq(minfo, 0);
407 	memset(vblank, 0, sizeof(*vblank));
408 	vblank->flags = FB_VBLANK_HAVE_VCOUNT | FB_VBLANK_HAVE_VBLANK;
409 	/* mask out reserved bits + field number (odd/even) */
410 	vblank->vcount = mga_inl(0x3C48) & 0x000007FF;
411 	/* compatibility stuff */
412 	if (vblank->vcount >= m2info->fbcon.var.yres)
413 		vblank->flags |= FB_VBLANK_VBLANKING;
414 	if (test_bit(0, &minfo->irq_flags)) {
415                 vblank->flags |= FB_VBLANK_HAVE_COUNT;
416                 /* Only one writer, aligned int value...
417                    it should work without lock and without atomic_t */
418 		vblank->count = minfo->crtc2.vsync.cnt;
419         }
420 	return 0;
421 }
422 
423 static int matroxfb_dh_ioctl(struct fb_info *info,
424 		unsigned int cmd,
425 		unsigned long arg)
426 {
427 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
428 	struct matrox_fb_info *minfo = m2info->primary_dev;
429 
430 	DBG(__func__)
431 
432 	switch (cmd) {
433 		case FBIOGET_VBLANK:
434 			{
435 				struct fb_vblank vblank;
436 				int err;
437 
438 				err = matroxfb_dh_get_vblank(m2info, &vblank);
439 				if (err)
440 					return err;
441 				if (copy_to_user((void __user *)arg, &vblank, sizeof(vblank)))
442 					return -EFAULT;
443 				return 0;
444 			}
445 		case FBIO_WAITFORVSYNC:
446 			{
447 				u_int32_t crt;
448 
449 				if (get_user(crt, (u_int32_t __user *)arg))
450 					return -EFAULT;
451 
452 				if (crt != 0)
453 					return -ENODEV;
454 				return matroxfb_wait_for_sync(minfo, 1);
455 			}
456 		case MATROXFB_SET_OUTPUT_MODE:
457 		case MATROXFB_GET_OUTPUT_MODE:
458 		case MATROXFB_GET_ALL_OUTPUTS:
459 			{
460 				return minfo->fbcon.fbops->fb_ioctl(&minfo->fbcon, cmd, arg);
461 			}
462 		case MATROXFB_SET_OUTPUT_CONNECTION:
463 			{
464 				u_int32_t tmp;
465 				int out;
466 				int changes;
467 
468 				if (get_user(tmp, (u_int32_t __user *)arg))
469 					return -EFAULT;
470 				for (out = 0; out < 32; out++) {
471 					if (tmp & (1 << out)) {
472 						if (out >= MATROXFB_MAX_OUTPUTS)
473 							return -ENXIO;
474 						if (!minfo->outputs[out].output)
475 							return -ENXIO;
476 						switch (minfo->outputs[out].src) {
477 							case MATROXFB_SRC_NONE:
478 							case MATROXFB_SRC_CRTC2:
479 								break;
480 							default:
481 								return -EBUSY;
482 						}
483 					}
484 				}
485 				if (minfo->devflags.panellink) {
486 					if (tmp & MATROXFB_OUTPUT_CONN_DFP)
487 						return -EINVAL;
488 					if ((minfo->outputs[2].src == MATROXFB_SRC_CRTC1) && tmp)
489 						return -EBUSY;
490 				}
491 				changes = 0;
492 				for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
493 					if (tmp & (1 << out)) {
494 						if (minfo->outputs[out].src != MATROXFB_SRC_CRTC2) {
495 							changes = 1;
496 							minfo->outputs[out].src = MATROXFB_SRC_CRTC2;
497 						}
498 					} else if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2) {
499 						changes = 1;
500 						minfo->outputs[out].src = MATROXFB_SRC_NONE;
501 					}
502 				}
503 				if (!changes)
504 					return 0;
505 				matroxfb_dh_set_par(info);
506 				return 0;
507 			}
508 		case MATROXFB_GET_OUTPUT_CONNECTION:
509 			{
510 				u_int32_t conn = 0;
511 				int out;
512 
513 				for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
514 					if (minfo->outputs[out].src == MATROXFB_SRC_CRTC2) {
515 						conn |= 1 << out;
516 					}
517 				}
518 				if (put_user(conn, (u_int32_t __user *)arg))
519 					return -EFAULT;
520 				return 0;
521 			}
522 		case MATROXFB_GET_AVAILABLE_OUTPUTS:
523 			{
524 				u_int32_t tmp = 0;
525 				int out;
526 
527 				for (out = 0; out < MATROXFB_MAX_OUTPUTS; out++) {
528 					if (minfo->outputs[out].output) {
529 						switch (minfo->outputs[out].src) {
530 							case MATROXFB_SRC_NONE:
531 							case MATROXFB_SRC_CRTC2:
532 								tmp |= 1 << out;
533 								break;
534 						}
535 					}
536 				}
537 				if (minfo->devflags.panellink) {
538 					tmp &= ~MATROXFB_OUTPUT_CONN_DFP;
539 					if (minfo->outputs[2].src == MATROXFB_SRC_CRTC1) {
540 						tmp = 0;
541 					}
542 				}
543 				if (put_user(tmp, (u_int32_t __user *)arg))
544 					return -EFAULT;
545 				return 0;
546 			}
547 	}
548 	return -ENOTTY;
549 #undef m2info
550 }
551 
552 static int matroxfb_dh_blank(int blank, struct fb_info* info) {
553 #define m2info (container_of(info, struct matroxfb_dh_fb_info, fbcon))
554 	switch (blank) {
555 		case 1:
556 		case 2:
557 		case 3:
558 		case 4:
559 		default:;
560 	}
561 	/* do something... */
562 	return 0;
563 #undef m2info
564 }
565 
566 static const struct fb_ops matroxfb_dh_ops = {
567 	.owner =	THIS_MODULE,
568 	.fb_open =	matroxfb_dh_open,
569 	.fb_release =	matroxfb_dh_release,
570 	.fb_check_var =	matroxfb_dh_check_var,
571 	.fb_set_par =	matroxfb_dh_set_par,
572 	.fb_setcolreg =	matroxfb_dh_setcolreg,
573 	.fb_pan_display =matroxfb_dh_pan_display,
574 	.fb_blank =	matroxfb_dh_blank,
575 	.fb_ioctl =	matroxfb_dh_ioctl,
576 	.fb_fillrect =	cfb_fillrect,
577 	.fb_copyarea =	cfb_copyarea,
578 	.fb_imageblit =	cfb_imageblit,
579 };
580 
581 static struct fb_var_screeninfo matroxfb_dh_defined = {
582 		640,480,640,480,/* W,H, virtual W,H */
583 		0,0,		/* offset */
584 		32,		/* depth */
585 		0,		/* gray */
586 		{0,0,0},	/* R */
587 		{0,0,0},	/* G */
588 		{0,0,0},	/* B */
589 		{0,0,0},	/* alpha */
590 		0,		/* nonstd */
591 		FB_ACTIVATE_NOW,
592 		-1,-1,		/* display size */
593 		0,		/* accel flags */
594 		39721L,48L,16L,33L,10L,
595 		96L,2,0,	/* no sync info */
596 		FB_VMODE_NONINTERLACED,
597 };
598 
599 static int matroxfb_dh_regit(const struct matrox_fb_info *minfo,
600 			     struct matroxfb_dh_fb_info *m2info)
601 {
602 #define minfo (m2info->primary_dev)
603 	void* oldcrtc2;
604 
605 	m2info->fbcon.fbops = &matroxfb_dh_ops;
606 	m2info->fbcon.flags = FBINFO_FLAG_DEFAULT;
607 	m2info->fbcon.flags |= FBINFO_HWACCEL_XPAN |
608 			       FBINFO_HWACCEL_YPAN;
609 	m2info->fbcon.pseudo_palette = m2info->cmap;
610 	fb_alloc_cmap(&m2info->fbcon.cmap, 256, 1);
611 
612 	if (mem < 64)
613 		mem *= 1024;
614 	if (mem < 64*1024)
615 		mem *= 1024;
616 	mem &= ~0x00000FFF;	/* PAGE_MASK? */
617 	if (minfo->video.len_usable + mem <= minfo->video.len)
618 		m2info->video.offbase = minfo->video.len - mem;
619 	else if (minfo->video.len < mem) {
620 		return -ENOMEM;
621 	} else { /* check yres on first head... */
622 		m2info->video.borrowed = mem;
623 		minfo->video.len_usable -= mem;
624 		m2info->video.offbase = minfo->video.len_usable;
625 	}
626 	m2info->video.base = minfo->video.base + m2info->video.offbase;
627 	m2info->video.len = m2info->video.len_usable = m2info->video.len_maximum = mem;
628 	m2info->video.vbase.vaddr = vaddr_va(minfo->video.vbase) + m2info->video.offbase;
629 	m2info->mmio.base = minfo->mmio.base;
630 	m2info->mmio.vbase = minfo->mmio.vbase;
631 	m2info->mmio.len = minfo->mmio.len;
632 
633 	matroxfb_dh_init_fix(m2info);
634 	if (register_framebuffer(&m2info->fbcon)) {
635 		return -ENXIO;
636 	}
637 	if (!m2info->initialized)
638 		fb_set_var(&m2info->fbcon, &matroxfb_dh_defined);
639 	down_write(&minfo->crtc2.lock);
640 	oldcrtc2 = minfo->crtc2.info;
641 	minfo->crtc2.info = m2info;
642 	up_write(&minfo->crtc2.lock);
643 	if (oldcrtc2) {
644 		printk(KERN_ERR "matroxfb_crtc2: Internal consistency check failed: crtc2 already present: %p\n",
645 			oldcrtc2);
646 	}
647 	return 0;
648 #undef minfo
649 }
650 
651 /* ************************** */
652 
653 static int matroxfb_dh_registerfb(struct matroxfb_dh_fb_info* m2info) {
654 #define minfo (m2info->primary_dev)
655 	if (matroxfb_dh_regit(minfo, m2info)) {
656 		printk(KERN_ERR "matroxfb_crtc2: secondary head failed to register\n");
657 		return -1;
658 	}
659 	printk(KERN_INFO "matroxfb_crtc2: secondary head of fb%u was registered as fb%u\n",
660 		minfo->fbcon.node, m2info->fbcon.node);
661 	m2info->fbcon_registered = 1;
662 	return 0;
663 #undef minfo
664 }
665 
666 static void matroxfb_dh_deregisterfb(struct matroxfb_dh_fb_info* m2info) {
667 #define minfo (m2info->primary_dev)
668 	if (m2info->fbcon_registered) {
669 		int id;
670 		struct matroxfb_dh_fb_info* crtc2;
671 
672 		down_write(&minfo->crtc2.lock);
673 		crtc2 = minfo->crtc2.info;
674 		if (crtc2 == m2info)
675 			minfo->crtc2.info = NULL;
676 		up_write(&minfo->crtc2.lock);
677 		if (crtc2 != m2info) {
678 			printk(KERN_ERR "matroxfb_crtc2: Internal consistency check failed: crtc2 mismatch at unload: %p != %p\n",
679 				crtc2, m2info);
680 			printk(KERN_ERR "matroxfb_crtc2: Expect kernel crash after module unload.\n");
681 			return;
682 		}
683 		id = m2info->fbcon.node;
684 		unregister_framebuffer(&m2info->fbcon);
685 		/* return memory back to primary head */
686 		minfo->video.len_usable += m2info->video.borrowed;
687 		printk(KERN_INFO "matroxfb_crtc2: fb%u unregistered\n", id);
688 		m2info->fbcon_registered = 0;
689 	}
690 #undef minfo
691 }
692 
693 static void* matroxfb_crtc2_probe(struct matrox_fb_info* minfo) {
694 	struct matroxfb_dh_fb_info* m2info;
695 
696 	/* hardware is CRTC2 incapable... */
697 	if (!minfo->devflags.crtc2)
698 		return NULL;
699 	m2info = kzalloc(sizeof(*m2info), GFP_KERNEL);
700 	if (!m2info)
701 		return NULL;
702 
703 	m2info->primary_dev = minfo;
704 	if (matroxfb_dh_registerfb(m2info)) {
705 		kfree(m2info);
706 		printk(KERN_ERR "matroxfb_crtc2: CRTC2 framebuffer failed to register\n");
707 		return NULL;
708 	}
709 	return m2info;
710 }
711 
712 static void matroxfb_crtc2_remove(struct matrox_fb_info* minfo, void* crtc2) {
713 	matroxfb_dh_deregisterfb(crtc2);
714 	kfree(crtc2);
715 }
716 
717 static struct matroxfb_driver crtc2 = {
718 		.name =		"Matrox G400 CRTC2",
719 		.probe =	matroxfb_crtc2_probe,
720 		.remove =	matroxfb_crtc2_remove };
721 
722 static int matroxfb_crtc2_init(void) {
723 	if (fb_get_options("matrox_crtc2fb", NULL))
724 		return -ENODEV;
725 
726 	matroxfb_register_driver(&crtc2);
727 	return 0;
728 }
729 
730 static void matroxfb_crtc2_exit(void) {
731 	matroxfb_unregister_driver(&crtc2);
732 }
733 
734 MODULE_AUTHOR("(c) 1999-2002 Petr Vandrovec <vandrove@vc.cvut.cz>");
735 MODULE_DESCRIPTION("Matrox G400 CRTC2 driver");
736 MODULE_LICENSE("GPL");
737 module_init(matroxfb_crtc2_init);
738 module_exit(matroxfb_crtc2_exit);
739 /* we do not have __setup() yet */
740