xref: /linux/drivers/video/fbdev/core/svgalib.c (revision 484f0a071f8d482649eaf025dee7b76a7202fec9)
1 /*
2  * Common utility functions for VGA-based graphics cards.
3  *
4  * Copyright (c) 2006-2007 Ondrej Zajicek <santiago@crfreenet.org>
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file COPYING in the main directory of this archive for
8  * more details.
9  *
10  * Some parts are based on David Boucher's viafb (http://davesdomain.org.uk/viafb/)
11  */
12 
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/fb.h>
17 #include <linux/math.h>
18 #include <linux/svga.h>
19 #include <asm/types.h>
20 #include <asm/io.h>
21 
22 
23 /* Write a CRT register value spread across multiple registers */
24 void svga_wcrt_multi(void __iomem *regbase, const struct vga_regset *regset, u32 value)
25 {
26 	u8 regval, bitval, bitnum;
27 
28 	while (regset->regnum != VGA_REGSET_END_VAL) {
29 		regval = vga_rcrt(regbase, regset->regnum);
30 		bitnum = regset->lowbit;
31 		while (bitnum <= regset->highbit) {
32 			bitval = 1 << bitnum;
33 			regval = regval & ~bitval;
34 			if (value & 1) regval = regval | bitval;
35 			bitnum ++;
36 			value = value >> 1;
37 		}
38 		vga_wcrt(regbase, regset->regnum, regval);
39 		regset ++;
40 	}
41 }
42 
43 /* Write a sequencer register value spread across multiple registers */
44 void svga_wseq_multi(void __iomem *regbase, const struct vga_regset *regset, u32 value)
45 {
46 	u8 regval, bitval, bitnum;
47 
48 	while (regset->regnum != VGA_REGSET_END_VAL) {
49 		regval = vga_rseq(regbase, regset->regnum);
50 		bitnum = regset->lowbit;
51 		while (bitnum <= regset->highbit) {
52 			bitval = 1 << bitnum;
53 			regval = regval & ~bitval;
54 			if (value & 1) regval = regval | bitval;
55 			bitnum ++;
56 			value = value >> 1;
57 		}
58 		vga_wseq(regbase, regset->regnum, regval);
59 		regset ++;
60 	}
61 }
62 
63 static unsigned int svga_regset_size(const struct vga_regset *regset)
64 {
65 	u8 count = 0;
66 
67 	while (regset->regnum != VGA_REGSET_END_VAL) {
68 		count += regset->highbit - regset->lowbit + 1;
69 		regset ++;
70 	}
71 	return 1 << count;
72 }
73 
74 
75 /* ------------------------------------------------------------------------- */
76 
77 
78 /* Set graphics controller registers to sane values */
79 void svga_set_default_gfx_regs(void __iomem *regbase)
80 {
81 	/* All standard GFX registers (GR00 - GR08) */
82 	vga_wgfx(regbase, VGA_GFX_SR_VALUE, 0x00);
83 	vga_wgfx(regbase, VGA_GFX_SR_ENABLE, 0x00);
84 	vga_wgfx(regbase, VGA_GFX_COMPARE_VALUE, 0x00);
85 	vga_wgfx(regbase, VGA_GFX_DATA_ROTATE, 0x00);
86 	vga_wgfx(regbase, VGA_GFX_PLANE_READ, 0x00);
87 	vga_wgfx(regbase, VGA_GFX_MODE, 0x00);
88 /*	vga_wgfx(regbase, VGA_GFX_MODE, 0x20); */
89 /*	vga_wgfx(regbase, VGA_GFX_MODE, 0x40); */
90 	vga_wgfx(regbase, VGA_GFX_MISC, 0x05);
91 /*	vga_wgfx(regbase, VGA_GFX_MISC, 0x01); */
92 	vga_wgfx(regbase, VGA_GFX_COMPARE_MASK, 0x0F);
93 	vga_wgfx(regbase, VGA_GFX_BIT_MASK, 0xFF);
94 }
95 
96 /* Set attribute controller registers to sane values */
97 void svga_set_default_atc_regs(void __iomem *regbase)
98 {
99 	u8 count;
100 
101 	vga_r(regbase, 0x3DA);
102 	vga_w(regbase, VGA_ATT_W, 0x00);
103 
104 	/* All standard ATC registers (AR00 - AR14) */
105 	for (count = 0; count <= 0xF; count ++)
106 		svga_wattr(regbase, count, count);
107 
108 	svga_wattr(regbase, VGA_ATC_MODE, 0x01);
109 /*	svga_wattr(regbase, VGA_ATC_MODE, 0x41); */
110 	svga_wattr(regbase, VGA_ATC_OVERSCAN, 0x00);
111 	svga_wattr(regbase, VGA_ATC_PLANE_ENABLE, 0x0F);
112 	svga_wattr(regbase, VGA_ATC_PEL, 0x00);
113 	svga_wattr(regbase, VGA_ATC_COLOR_PAGE, 0x00);
114 
115 	vga_r(regbase, 0x3DA);
116 	vga_w(regbase, VGA_ATT_W, 0x20);
117 }
118 
119 /* Set sequencer registers to sane values */
120 void svga_set_default_seq_regs(void __iomem *regbase)
121 {
122 	/* Standard sequencer registers (SR01 - SR04), SR00 is not set */
123 	vga_wseq(regbase, VGA_SEQ_CLOCK_MODE, VGA_SR01_CHAR_CLK_8DOTS);
124 	vga_wseq(regbase, VGA_SEQ_PLANE_WRITE, VGA_SR02_ALL_PLANES);
125 	vga_wseq(regbase, VGA_SEQ_CHARACTER_MAP, 0x00);
126 /*	vga_wseq(regbase, VGA_SEQ_MEMORY_MODE, VGA_SR04_EXT_MEM | VGA_SR04_SEQ_MODE | VGA_SR04_CHN_4M); */
127 	vga_wseq(regbase, VGA_SEQ_MEMORY_MODE, VGA_SR04_EXT_MEM | VGA_SR04_SEQ_MODE);
128 }
129 
130 /* Set CRTC registers to sane values */
131 void svga_set_default_crt_regs(void __iomem *regbase)
132 {
133 	/* Standard CRT registers CR03 CR08 CR09 CR14 CR17 */
134 	svga_wcrt_mask(regbase, 0x03, 0x80, 0x80);	/* Enable vertical retrace EVRA */
135 	vga_wcrt(regbase, VGA_CRTC_PRESET_ROW, 0);
136 	svga_wcrt_mask(regbase, VGA_CRTC_MAX_SCAN, 0, 0x1F);
137 	vga_wcrt(regbase, VGA_CRTC_UNDERLINE, 0);
138 	vga_wcrt(regbase, VGA_CRTC_MODE, 0xE3);
139 }
140 
141 void svga_set_textmode_vga_regs(void __iomem *regbase)
142 {
143 	/* svga_wseq_mask(regbase, 0x1, 0x00, 0x01); */   /* Switch 8/9 pixel per char */
144 	vga_wseq(regbase, VGA_SEQ_MEMORY_MODE, VGA_SR04_EXT_MEM);
145 	vga_wseq(regbase, VGA_SEQ_PLANE_WRITE, 0x03);
146 
147 	vga_wcrt(regbase, VGA_CRTC_MAX_SCAN, 0x0f); /* 0x4f */
148 	vga_wcrt(regbase, VGA_CRTC_UNDERLINE, 0x1f);
149 	svga_wcrt_mask(regbase, VGA_CRTC_MODE, 0x23, 0x7f);
150 
151 	vga_wcrt(regbase, VGA_CRTC_CURSOR_START, 0x0d);
152 	vga_wcrt(regbase, VGA_CRTC_CURSOR_END, 0x0e);
153 	vga_wcrt(regbase, VGA_CRTC_CURSOR_HI, 0x00);
154 	vga_wcrt(regbase, VGA_CRTC_CURSOR_LO, 0x00);
155 
156 	vga_wgfx(regbase, VGA_GFX_MODE, 0x10); /* Odd/even memory mode */
157 	vga_wgfx(regbase, VGA_GFX_MISC, 0x0E); /* Misc graphics register - text mode enable */
158 	vga_wgfx(regbase, VGA_GFX_COMPARE_MASK, 0x00);
159 
160 	vga_r(regbase, 0x3DA);
161 	vga_w(regbase, VGA_ATT_W, 0x00);
162 
163 	svga_wattr(regbase, 0x10, 0x0C);			/* Attribute Mode Control Register - text mode, blinking and line graphics */
164 	svga_wattr(regbase, 0x13, 0x08);			/* Horizontal Pixel Panning Register  */
165 
166 	vga_r(regbase, 0x3DA);
167 	vga_w(regbase, VGA_ATT_W, 0x20);
168 }
169 
170 #if 0
171 void svga_dump_var(struct fb_var_screeninfo *var, int node)
172 {
173 	pr_debug("fb%d: var.vmode         : 0x%X\n", node, var->vmode);
174 	pr_debug("fb%d: var.xres          : %d\n", node, var->xres);
175 	pr_debug("fb%d: var.yres          : %d\n", node, var->yres);
176 	pr_debug("fb%d: var.bits_per_pixel: %d\n", node, var->bits_per_pixel);
177 	pr_debug("fb%d: var.xres_virtual  : %d\n", node, var->xres_virtual);
178 	pr_debug("fb%d: var.yres_virtual  : %d\n", node, var->yres_virtual);
179 	pr_debug("fb%d: var.left_margin   : %d\n", node, var->left_margin);
180 	pr_debug("fb%d: var.right_margin  : %d\n", node, var->right_margin);
181 	pr_debug("fb%d: var.upper_margin  : %d\n", node, var->upper_margin);
182 	pr_debug("fb%d: var.lower_margin  : %d\n", node, var->lower_margin);
183 	pr_debug("fb%d: var.hsync_len     : %d\n", node, var->hsync_len);
184 	pr_debug("fb%d: var.vsync_len     : %d\n", node, var->vsync_len);
185 	pr_debug("fb%d: var.sync          : 0x%X\n", node, var->sync);
186 	pr_debug("fb%d: var.pixclock      : %d\n\n", node, var->pixclock);
187 }
188 #endif  /*  0  */
189 
190 
191 /* ------------------------------------------------------------------------- */
192 
193 
194 void svga_settile(struct fb_info *info, struct fb_tilemap *map)
195 {
196 	const u8 *font = map->data;
197 	u8 __iomem *fb = (u8 __iomem *)info->screen_base;
198 	int i, c;
199 
200 	if ((map->width != 8) || (map->height != 16) ||
201 	    (map->depth != 1) || (map->length != 256)) {
202 		fb_err(info, "unsupported font parameters: width %d, height %d, depth %d, length %d\n",
203 		       map->width, map->height, map->depth, map->length);
204 		return;
205 	}
206 
207 	fb += 2;
208 	for (c = 0; c < map->length; c++) {
209 		for (i = 0; i < map->height; i++) {
210 			fb_writeb(font[i], fb + i * 4);
211 //			fb[i * 4] = font[i];
212 		}
213 		fb += 128;
214 		font += map->height;
215 	}
216 }
217 
218 /* Copy area in text (tileblit) mode */
219 void svga_tilecopy(struct fb_info *info, struct fb_tilearea *area)
220 {
221 	int dx, dy;
222 	/*  colstride is halved in this function because u16 are used */
223 	int colstride = 1 << (info->fix.type_aux & FB_AUX_TEXT_SVGA_MASK);
224 	int rowstride = colstride * (info->var.xres_virtual / 8);
225 	u16 __iomem *fb = (u16 __iomem *) info->screen_base;
226 	u16 __iomem *src, *dst;
227 
228 	if ((area->sy > area->dy) ||
229 	    ((area->sy == area->dy) && (area->sx > area->dx))) {
230 		src = fb + area->sx * colstride + area->sy * rowstride;
231 		dst = fb + area->dx * colstride + area->dy * rowstride;
232 	    } else {
233 		src = fb + (area->sx + area->width - 1) * colstride
234 			 + (area->sy + area->height - 1) * rowstride;
235 		dst = fb + (area->dx + area->width - 1) * colstride
236 			 + (area->dy + area->height - 1) * rowstride;
237 
238 		colstride = -colstride;
239 		rowstride = -rowstride;
240 	    }
241 
242 	for (dy = 0; dy < area->height; dy++) {
243 		u16 __iomem *src2 = src;
244 		u16 __iomem *dst2 = dst;
245 		for (dx = 0; dx < area->width; dx++) {
246 			fb_writew(fb_readw(src2), dst2);
247 //			*dst2 = *src2;
248 			src2 += colstride;
249 			dst2 += colstride;
250 		}
251 		src += rowstride;
252 		dst += rowstride;
253 	}
254 }
255 
256 /* Fill area in text (tileblit) mode */
257 void svga_tilefill(struct fb_info *info, struct fb_tilerect *rect)
258 {
259 	int dx, dy;
260 	int colstride = 2 << (info->fix.type_aux & FB_AUX_TEXT_SVGA_MASK);
261 	int rowstride = colstride * (info->var.xres_virtual / 8);
262 	int attr = (0x0F & rect->bg) << 4 | (0x0F & rect->fg);
263 	u8 __iomem *fb = (u8 __iomem *)info->screen_base;
264 	fb += rect->sx * colstride + rect->sy * rowstride;
265 
266 	for (dy = 0; dy < rect->height; dy++) {
267 		u8 __iomem *fb2 = fb;
268 		for (dx = 0; dx < rect->width; dx++) {
269 			fb_writeb(rect->index, fb2);
270 			fb_writeb(attr, fb2 + 1);
271 			fb2 += colstride;
272 		}
273 		fb += rowstride;
274 	}
275 }
276 
277 /* Write text in text (tileblit) mode */
278 void svga_tileblit(struct fb_info *info, struct fb_tileblit *blit)
279 {
280 	int dx, dy, i;
281 	int colstride = 2 << (info->fix.type_aux & FB_AUX_TEXT_SVGA_MASK);
282 	int rowstride = colstride * (info->var.xres_virtual / 8);
283 	int attr = (0x0F & blit->bg) << 4 | (0x0F & blit->fg);
284 	u8 __iomem *fb = (u8 __iomem *)info->screen_base;
285 	fb += blit->sx * colstride + blit->sy * rowstride;
286 
287 	i=0;
288 	for (dy=0; dy < blit->height; dy ++) {
289 		u8 __iomem *fb2 = fb;
290 		for (dx = 0; dx < blit->width; dx ++) {
291 			fb_writeb(blit->indices[i], fb2);
292 			fb_writeb(attr, fb2 + 1);
293 			fb2 += colstride;
294 			i ++;
295 			if (i == blit->length) return;
296 		}
297 		fb += rowstride;
298 	}
299 
300 }
301 
302 /* Set cursor in text (tileblit) mode */
303 void svga_tilecursor(void __iomem *regbase, struct fb_info *info, struct fb_tilecursor *cursor)
304 {
305 	u8 cs = 0x0d;
306 	u8 ce = 0x0e;
307 	u16 pos =  cursor->sx + (info->var.xoffset /  8)
308 		+ (cursor->sy + (info->var.yoffset / 16))
309 		   * (info->var.xres_virtual / 8);
310 
311 	if (! cursor -> mode)
312 		return;
313 
314 	svga_wcrt_mask(regbase, 0x0A, 0x20, 0x20); /* disable cursor */
315 
316 	if (cursor -> shape == FB_TILE_CURSOR_NONE)
317 		return;
318 
319 	switch (cursor -> shape) {
320 	case FB_TILE_CURSOR_UNDERLINE:
321 		cs = 0x0d;
322 		break;
323 	case FB_TILE_CURSOR_LOWER_THIRD:
324 		cs = 0x09;
325 		break;
326 	case FB_TILE_CURSOR_LOWER_HALF:
327 		cs = 0x07;
328 		break;
329 	case FB_TILE_CURSOR_TWO_THIRDS:
330 		cs = 0x05;
331 		break;
332 	case FB_TILE_CURSOR_BLOCK:
333 		cs = 0x01;
334 		break;
335 	}
336 
337 	/* set cursor position */
338 	vga_wcrt(regbase, 0x0E, pos >> 8);
339 	vga_wcrt(regbase, 0x0F, pos & 0xFF);
340 
341 	vga_wcrt(regbase, 0x0B, ce); /* set cursor end */
342 	vga_wcrt(regbase, 0x0A, cs); /* set cursor start and enable it */
343 }
344 
345 int svga_get_tilemax(struct fb_info *info)
346 {
347 	return 256;
348 }
349 
350 /* Get capabilities of accelerator based on the mode */
351 
352 void svga_get_caps(struct fb_info *info, struct fb_blit_caps *caps,
353 		   struct fb_var_screeninfo *var)
354 {
355 	if (var->bits_per_pixel == 0) {
356 		/* can only support 256 8x16 bitmap */
357 		caps->x = 1 << (8 - 1);
358 		caps->y = 1 << (16 - 1);
359 		caps->len = 256;
360 	} else {
361 		caps->x = (var->bits_per_pixel == 4) ? 1 << (8 - 1) : ~(u32)0;
362 		caps->y = ~(u32)0;
363 		caps->len = ~(u32)0;
364 	}
365 }
366 EXPORT_SYMBOL(svga_get_caps);
367 
368 /* ------------------------------------------------------------------------- */
369 
370 
371 /*
372  *  Compute PLL settings (M, N, R)
373  *  F_VCO = (F_BASE * M) / N
374  *  F_OUT = F_VCO / (2^R)
375  */
376 int svga_compute_pll(const struct svga_pll *pll, u32 f_wanted, u16 *m, u16 *n, u16 *r, int node)
377 {
378 	u16 am, an, ar;
379 	u32 f_vco, f_current, delta_current, delta_best;
380 
381 	pr_debug("fb%d: ideal frequency: %d kHz\n", node, (unsigned int) f_wanted);
382 
383 	ar = pll->r_max;
384 	f_vco = f_wanted << ar;
385 
386 	/* overflow check */
387 	if ((f_vco >> ar) != f_wanted)
388 		return -EINVAL;
389 
390 	/* It is usually better to have greater VCO clock
391 	   because of better frequency stability.
392 	   So first try r_max, then r smaller. */
393 	while ((ar > pll->r_min) && (f_vco > pll->f_vco_max)) {
394 		ar--;
395 		f_vco = f_vco >> 1;
396 	}
397 
398 	/* VCO bounds check */
399 	if ((f_vco < pll->f_vco_min) || (f_vco > pll->f_vco_max))
400 		return -EINVAL;
401 
402 	delta_best = 0xFFFFFFFF;
403 	*m = 0;
404 	*n = 0;
405 	*r = ar;
406 
407 	am = pll->m_min;
408 	an = pll->n_min;
409 
410 	while ((am <= pll->m_max) && (an <= pll->n_max)) {
411 		f_current = (pll->f_base * am) / an;
412 		delta_current = abs_diff (f_current, f_vco);
413 
414 		if (delta_current < delta_best) {
415 			delta_best = delta_current;
416 			*m = am;
417 			*n = an;
418 		}
419 
420 		if (f_current <= f_vco) {
421 			am ++;
422 		} else {
423 			an ++;
424 		}
425 	}
426 
427 	f_current = (pll->f_base * *m) / *n;
428 	pr_debug("fb%d: found frequency: %d kHz (VCO %d kHz)\n", node, (int) (f_current >> ar), (int) f_current);
429 	pr_debug("fb%d: m = %d n = %d r = %d\n", node, (unsigned int) *m, (unsigned int) *n, (unsigned int) *r);
430 	return 0;
431 }
432 
433 
434 /* ------------------------------------------------------------------------- */
435 
436 
437 /* Check CRT timing values */
438 int svga_check_timings(const struct svga_timing_regs *tm, struct fb_var_screeninfo *var, int node)
439 {
440 	u32 value;
441 
442 	var->xres         = (var->xres+7)&~7;
443 	var->left_margin  = (var->left_margin+7)&~7;
444 	var->right_margin = (var->right_margin+7)&~7;
445 	var->hsync_len    = (var->hsync_len+7)&~7;
446 
447 	/* Check horizontal total */
448 	value = var->xres + var->left_margin + var->right_margin + var->hsync_len;
449 	if (((value / 8) - 5) >= svga_regset_size (tm->h_total_regs))
450 		return -EINVAL;
451 
452 	/* Check horizontal display and blank start */
453 	value = var->xres;
454 	if (((value / 8) - 1) >= svga_regset_size (tm->h_display_regs))
455 		return -EINVAL;
456 	if (((value / 8) - 1) >= svga_regset_size (tm->h_blank_start_regs))
457 		return -EINVAL;
458 
459 	/* Check horizontal sync start */
460 	value = var->xres + var->right_margin;
461 	if (((value / 8) - 1) >= svga_regset_size (tm->h_sync_start_regs))
462 		return -EINVAL;
463 
464 	/* Check horizontal blank end (or length) */
465 	value = var->left_margin + var->right_margin + var->hsync_len;
466 	if ((value == 0) || ((value / 8) >= svga_regset_size (tm->h_blank_end_regs)))
467 		return -EINVAL;
468 
469 	/* Check horizontal sync end (or length) */
470 	value = var->hsync_len;
471 	if ((value == 0) || ((value / 8) >= svga_regset_size (tm->h_sync_end_regs)))
472 		return -EINVAL;
473 
474 	/* Check vertical total */
475 	value = var->yres + var->upper_margin + var->lower_margin + var->vsync_len;
476 	if ((value - 1) >= svga_regset_size(tm->v_total_regs))
477 		return -EINVAL;
478 
479 	/* Check vertical display and blank start */
480 	value = var->yres;
481 	if ((value - 1) >= svga_regset_size(tm->v_display_regs))
482 		return -EINVAL;
483 	if ((value - 1) >= svga_regset_size(tm->v_blank_start_regs))
484 		return -EINVAL;
485 
486 	/* Check vertical sync start */
487 	value = var->yres + var->lower_margin;
488 	if ((value - 1) >= svga_regset_size(tm->v_sync_start_regs))
489 		return -EINVAL;
490 
491 	/* Check vertical blank end (or length) */
492 	value = var->upper_margin + var->lower_margin + var->vsync_len;
493 	if ((value == 0) || (value >= svga_regset_size (tm->v_blank_end_regs)))
494 		return -EINVAL;
495 
496 	/* Check vertical sync end  (or length) */
497 	value = var->vsync_len;
498 	if ((value == 0) || (value >= svga_regset_size (tm->v_sync_end_regs)))
499 		return -EINVAL;
500 
501 	return 0;
502 }
503 
504 /* Set CRT timing registers */
505 void svga_set_timings(void __iomem *regbase, const struct svga_timing_regs *tm,
506 		      struct fb_var_screeninfo *var,
507 		      u32 hmul, u32 hdiv, u32 vmul, u32 vdiv, u32 hborder, int node)
508 {
509 	u8 regval;
510 	u32 value;
511 
512 	value = var->xres + var->left_margin + var->right_margin + var->hsync_len;
513 	value = (value * hmul) / hdiv;
514 	pr_debug("fb%d: horizontal total      : %d\n", node, value);
515 	svga_wcrt_multi(regbase, tm->h_total_regs, (value / 8) - 5);
516 
517 	value = var->xres;
518 	value = (value * hmul) / hdiv;
519 	pr_debug("fb%d: horizontal display    : %d\n", node, value);
520 	svga_wcrt_multi(regbase, tm->h_display_regs, (value / 8) - 1);
521 
522 	value = var->xres;
523 	value = (value * hmul) / hdiv;
524 	pr_debug("fb%d: horizontal blank start: %d\n", node, value);
525 	svga_wcrt_multi(regbase, tm->h_blank_start_regs, (value / 8) - 1 + hborder);
526 
527 	value = var->xres + var->left_margin + var->right_margin + var->hsync_len;
528 	value = (value * hmul) / hdiv;
529 	pr_debug("fb%d: horizontal blank end  : %d\n", node, value);
530 	svga_wcrt_multi(regbase, tm->h_blank_end_regs, (value / 8) - 1 - hborder);
531 
532 	value = var->xres + var->right_margin;
533 	value = (value * hmul) / hdiv;
534 	pr_debug("fb%d: horizontal sync start : %d\n", node, value);
535 	svga_wcrt_multi(regbase, tm->h_sync_start_regs, (value / 8));
536 
537 	value = var->xres + var->right_margin + var->hsync_len;
538 	value = (value * hmul) / hdiv;
539 	pr_debug("fb%d: horizontal sync end   : %d\n", node, value);
540 	svga_wcrt_multi(regbase, tm->h_sync_end_regs, (value / 8));
541 
542 	value = var->yres + var->upper_margin + var->lower_margin + var->vsync_len;
543 	value = (value * vmul) / vdiv;
544 	pr_debug("fb%d: vertical total        : %d\n", node, value);
545 	svga_wcrt_multi(regbase, tm->v_total_regs, value - 2);
546 
547 	value = var->yres;
548 	value = (value * vmul) / vdiv;
549 	pr_debug("fb%d: vertical display      : %d\n", node, value);
550 	svga_wcrt_multi(regbase, tm->v_display_regs, value - 1);
551 
552 	value = var->yres;
553 	value = (value * vmul) / vdiv;
554 	pr_debug("fb%d: vertical blank start  : %d\n", node, value);
555 	svga_wcrt_multi(regbase, tm->v_blank_start_regs, value);
556 
557 	value = var->yres + var->upper_margin + var->lower_margin + var->vsync_len;
558 	value = (value * vmul) / vdiv;
559 	pr_debug("fb%d: vertical blank end    : %d\n", node, value);
560 	svga_wcrt_multi(regbase, tm->v_blank_end_regs, value - 2);
561 
562 	value = var->yres + var->lower_margin;
563 	value = (value * vmul) / vdiv;
564 	pr_debug("fb%d: vertical sync start   : %d\n", node, value);
565 	svga_wcrt_multi(regbase, tm->v_sync_start_regs, value);
566 
567 	value = var->yres + var->lower_margin + var->vsync_len;
568 	value = (value * vmul) / vdiv;
569 	pr_debug("fb%d: vertical sync end     : %d\n", node, value);
570 	svga_wcrt_multi(regbase, tm->v_sync_end_regs, value);
571 
572 	/* Set horizontal and vertical sync pulse polarity in misc register */
573 
574 	regval = vga_r(regbase, VGA_MIS_R);
575 	if (var->sync & FB_SYNC_HOR_HIGH_ACT) {
576 		pr_debug("fb%d: positive horizontal sync\n", node);
577 		regval = regval & ~0x80;
578 	} else {
579 		pr_debug("fb%d: negative horizontal sync\n", node);
580 		regval = regval | 0x80;
581 	}
582 	if (var->sync & FB_SYNC_VERT_HIGH_ACT) {
583 		pr_debug("fb%d: positive vertical sync\n", node);
584 		regval = regval & ~0x40;
585 	} else {
586 		pr_debug("fb%d: negative vertical sync\n\n", node);
587 		regval = regval | 0x40;
588 	}
589 	vga_w(regbase, VGA_MIS_W, regval);
590 }
591 
592 
593 /* ------------------------------------------------------------------------- */
594 
595 
596 static inline int match_format(const struct svga_fb_format *frm,
597 			       struct fb_var_screeninfo *var)
598 {
599 	int i = 0;
600 	int stored = -EINVAL;
601 
602 	while (frm->bits_per_pixel != SVGA_FORMAT_END_VAL)
603 	{
604 		if ((var->bits_per_pixel == frm->bits_per_pixel) &&
605 		    (var->red.length     <= frm->red.length)     &&
606 		    (var->green.length   <= frm->green.length)   &&
607 		    (var->blue.length    <= frm->blue.length)    &&
608 		    (var->transp.length  <= frm->transp.length)  &&
609 		    (var->nonstd	 == frm->nonstd))
610 			return i;
611 		if (var->bits_per_pixel == frm->bits_per_pixel)
612 			stored = i;
613 		i++;
614 		frm++;
615 	}
616 	return stored;
617 }
618 
619 int svga_match_format(const struct svga_fb_format *frm,
620 		      struct fb_var_screeninfo *var,
621 		      struct fb_fix_screeninfo *fix)
622 {
623 	int i = match_format(frm, var);
624 
625 	if (i >= 0) {
626 		var->bits_per_pixel = frm[i].bits_per_pixel;
627 		var->red            = frm[i].red;
628 		var->green          = frm[i].green;
629 		var->blue           = frm[i].blue;
630 		var->transp         = frm[i].transp;
631 		var->nonstd         = frm[i].nonstd;
632 		if (fix != NULL) {
633 			fix->type      = frm[i].type;
634 			fix->type_aux  = frm[i].type_aux;
635 			fix->visual    = frm[i].visual;
636 			fix->xpanstep  = frm[i].xpanstep;
637 		}
638 	}
639 
640 	return i;
641 }
642 
643 
644 EXPORT_SYMBOL(svga_wcrt_multi);
645 EXPORT_SYMBOL(svga_wseq_multi);
646 
647 EXPORT_SYMBOL(svga_set_default_gfx_regs);
648 EXPORT_SYMBOL(svga_set_default_atc_regs);
649 EXPORT_SYMBOL(svga_set_default_seq_regs);
650 EXPORT_SYMBOL(svga_set_default_crt_regs);
651 EXPORT_SYMBOL(svga_set_textmode_vga_regs);
652 
653 EXPORT_SYMBOL(svga_settile);
654 EXPORT_SYMBOL(svga_tilecopy);
655 EXPORT_SYMBOL(svga_tilefill);
656 EXPORT_SYMBOL(svga_tileblit);
657 EXPORT_SYMBOL(svga_tilecursor);
658 EXPORT_SYMBOL(svga_get_tilemax);
659 
660 EXPORT_SYMBOL(svga_compute_pll);
661 EXPORT_SYMBOL(svga_check_timings);
662 EXPORT_SYMBOL(svga_set_timings);
663 EXPORT_SYMBOL(svga_match_format);
664 
665 MODULE_AUTHOR("Ondrej Zajicek <santiago@crfreenet.org>");
666 MODULE_DESCRIPTION("Common utility functions for VGA-based graphics cards");
667 MODULE_LICENSE("GPL");
668