xref: /openbmc/linux/drivers/video/fbdev/vga16fb.c (revision 1d61d359)
1 /*
2  * linux/drivers/video/vga16.c -- VGA 16-color framebuffer driver
3  *
4  * Copyright 1999 Ben Pfaff <pfaffben@debian.org> and Petr Vandrovec <VANDROVE@vc.cvut.cz>
5  * Based on VGA info at http://www.goodnet.com/~tinara/FreeVGA/home.htm
6  * Based on VESA framebuffer (c) 1998 Gerd Knorr <kraxel@goldbach.in-berlin.de>
7  *
8  * This file is subject to the terms and conditions of the GNU General
9  * Public License.  See the file COPYING in the main directory of this
10  * archive for more details.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/errno.h>
16 #include <linux/string.h>
17 #include <linux/mm.h>
18 #include <linux/delay.h>
19 #include <linux/fb.h>
20 #include <linux/ioport.h>
21 #include <linux/init.h>
22 #include <linux/platform_device.h>
23 #include <linux/screen_info.h>
24 
25 #include <asm/io.h>
26 #include <video/vga.h>
27 
28 #define VGA_FB_PHYS 0xA0000
29 #define VGA_FB_PHYS_LEN 65536
30 
31 #define MODE_SKIP4	1
32 #define MODE_8BPP	2
33 #define MODE_CFB	4
34 #define MODE_TEXT	8
35 
36 /* --------------------------------------------------------------------- */
37 
38 /*
39  * card parameters
40  */
41 
42 struct vga16fb_par {
43 	/* structure holding original VGA register settings when the
44            screen is blanked */
45 	struct {
46 		unsigned char	SeqCtrlIndex;	  /* Sequencer Index reg.   */
47 		unsigned char	CrtCtrlIndex;	  /* CRT-Contr. Index reg.  */
48 		unsigned char	CrtMiscIO;	  /* Miscellaneous register */
49 		unsigned char	HorizontalTotal;  /* CRT-Controller:00h */
50 		unsigned char	HorizDisplayEnd;  /* CRT-Controller:01h */
51 		unsigned char	StartHorizRetrace;/* CRT-Controller:04h */
52 		unsigned char	EndHorizRetrace;  /* CRT-Controller:05h */
53 		unsigned char	Overflow;	  /* CRT-Controller:07h */
54 		unsigned char	StartVertRetrace; /* CRT-Controller:10h */
55 		unsigned char	EndVertRetrace;	  /* CRT-Controller:11h */
56 		unsigned char	ModeControl;	  /* CRT-Controller:17h */
57 		unsigned char	ClockingMode;	  /* Seq-Controller:01h */
58 	} vga_state;
59 	struct vgastate state;
60 	unsigned int ref_count;
61 	int palette_blanked, vesa_blanked, mode, isVGA;
62 	u8 misc, pel_msk, vss, clkdiv;
63 	u8 crtc[VGA_CRT_C];
64 };
65 
66 /* --------------------------------------------------------------------- */
67 
68 static struct fb_var_screeninfo vga16fb_defined = {
69 	.xres		= 640,
70 	.yres		= 480,
71 	.xres_virtual	= 640,
72 	.yres_virtual	= 480,
73 	.bits_per_pixel	= 4,
74 	.activate	= FB_ACTIVATE_TEST,
75 	.height		= -1,
76 	.width		= -1,
77 	.pixclock	= 39721,
78 	.left_margin	= 48,
79 	.right_margin	= 16,
80 	.upper_margin	= 33,
81 	.lower_margin	= 10,
82 	.hsync_len 	= 96,
83 	.vsync_len	= 2,
84 	.vmode		= FB_VMODE_NONINTERLACED,
85 };
86 
87 /* name should not depend on EGA/VGA */
88 static const struct fb_fix_screeninfo vga16fb_fix = {
89 	.id		= "VGA16 VGA",
90 	.smem_start	= VGA_FB_PHYS,
91 	.smem_len	= VGA_FB_PHYS_LEN,
92 	.type		= FB_TYPE_VGA_PLANES,
93 	.type_aux	= FB_AUX_VGA_PLANES_VGA4,
94 	.visual		= FB_VISUAL_PSEUDOCOLOR,
95 	.xpanstep	= 8,
96 	.ypanstep	= 1,
97 	.line_length	= 640 / 8,
98 	.accel		= FB_ACCEL_NONE
99 };
100 
101 /* The VGA's weird architecture often requires that we read a byte and
102    write a byte to the same location.  It doesn't matter *what* byte
103    we write, however.  This is because all the action goes on behind
104    the scenes in the VGA's 32-bit latch register, and reading and writing
105    video memory just invokes latch behavior.
106 
107    To avoid race conditions (is this necessary?), reading and writing
108    the memory byte should be done with a single instruction.  One
109    suitable instruction is the x86 bitwise OR.  The following
110    read-modify-write routine should optimize to one such bitwise
111    OR. */
112 static inline void rmw(volatile char __iomem *p)
113 {
114 	readb(p);
115 	writeb(1, p);
116 }
117 
118 /* Set the Graphics Mode Register, and return its previous value.
119    Bits 0-1 are write mode, bit 3 is read mode. */
120 static inline int setmode(int mode)
121 {
122 	int oldmode;
123 
124 	oldmode = vga_io_rgfx(VGA_GFX_MODE);
125 	vga_io_w(VGA_GFX_D, mode);
126 	return oldmode;
127 }
128 
129 /* Select the Bit Mask Register and return its value. */
130 static inline int selectmask(void)
131 {
132 	return vga_io_rgfx(VGA_GFX_BIT_MASK);
133 }
134 
135 /* Set the value of the Bit Mask Register.  It must already have been
136    selected with selectmask(). */
137 static inline void setmask(int mask)
138 {
139 	vga_io_w(VGA_GFX_D, mask);
140 }
141 
142 /* Set the Data Rotate Register and return its old value.
143    Bits 0-2 are rotate count, bits 3-4 are logical operation
144    (0=NOP, 1=AND, 2=OR, 3=XOR). */
145 static inline int setop(int op)
146 {
147 	int oldop;
148 
149 	oldop = vga_io_rgfx(VGA_GFX_DATA_ROTATE);
150 	vga_io_w(VGA_GFX_D, op);
151 	return oldop;
152 }
153 
154 /* Set the Enable Set/Reset Register and return its old value.
155    The code here always uses value 0xf for this register. */
156 static inline int setsr(int sr)
157 {
158 	int oldsr;
159 
160 	oldsr = vga_io_rgfx(VGA_GFX_SR_ENABLE);
161 	vga_io_w(VGA_GFX_D, sr);
162 	return oldsr;
163 }
164 
165 /* Set the Set/Reset Register and return its old value. */
166 static inline int setcolor(int color)
167 {
168 	int oldcolor;
169 
170 	oldcolor = vga_io_rgfx(VGA_GFX_SR_VALUE);
171 	vga_io_w(VGA_GFX_D, color);
172 	return oldcolor;
173 }
174 
175 /* Return the value in the Graphics Address Register. */
176 static inline int getindex(void)
177 {
178 	return vga_io_r(VGA_GFX_I);
179 }
180 
181 /* Set the value in the Graphics Address Register. */
182 static inline void setindex(int index)
183 {
184 	vga_io_w(VGA_GFX_I, index);
185 }
186 
187 static void vga16fb_pan_var(struct fb_info *info,
188 			    struct fb_var_screeninfo *var)
189 {
190 	struct vga16fb_par *par = info->par;
191 	u32 xoffset, pos;
192 
193 	xoffset = var->xoffset;
194 	if (info->var.bits_per_pixel == 8) {
195 		pos = (info->var.xres_virtual * var->yoffset + xoffset) >> 2;
196 	} else if (par->mode & MODE_TEXT) {
197 		int fh = 16; // FIXME !!! font height. Fugde for now.
198 		pos = (info->var.xres_virtual * (var->yoffset / fh) + xoffset) >> 3;
199 	} else {
200 		if (info->var.nonstd)
201 			xoffset--;
202 		pos = (info->var.xres_virtual * var->yoffset + xoffset) >> 3;
203 	}
204 	vga_io_wcrt(VGA_CRTC_START_HI, pos >> 8);
205 	vga_io_wcrt(VGA_CRTC_START_LO, pos & 0xFF);
206 	/* if we support CFB4, then we must! support xoffset with pixel
207 	 * granularity if someone supports xoffset in bit resolution */
208 	vga_io_r(VGA_IS1_RC);		/* reset flip-flop */
209 	vga_io_w(VGA_ATT_IW, VGA_ATC_PEL);
210 	if (info->var.bits_per_pixel == 8)
211 		vga_io_w(VGA_ATT_IW, (xoffset & 3) << 1);
212 	else
213 		vga_io_w(VGA_ATT_IW, xoffset & 7);
214 	vga_io_r(VGA_IS1_RC);
215 	vga_io_w(VGA_ATT_IW, 0x20);
216 }
217 
218 static void vga16fb_update_fix(struct fb_info *info)
219 {
220 	if (info->var.bits_per_pixel == 4) {
221 		if (info->var.nonstd) {
222 			info->fix.type = FB_TYPE_PACKED_PIXELS;
223 			info->fix.line_length = info->var.xres_virtual / 2;
224 		} else {
225 			info->fix.type = FB_TYPE_VGA_PLANES;
226 			info->fix.type_aux = FB_AUX_VGA_PLANES_VGA4;
227 			info->fix.line_length = info->var.xres_virtual / 8;
228 		}
229 	} else if (info->var.bits_per_pixel == 0) {
230 		info->fix.type = FB_TYPE_TEXT;
231 		info->fix.type_aux = FB_AUX_TEXT_CGA;
232 		info->fix.line_length = info->var.xres_virtual / 4;
233 	} else {	/* 8bpp */
234 		if (info->var.nonstd) {
235 			info->fix.type = FB_TYPE_VGA_PLANES;
236 			info->fix.type_aux = FB_AUX_VGA_PLANES_CFB8;
237 			info->fix.line_length = info->var.xres_virtual / 4;
238 		} else {
239 			info->fix.type = FB_TYPE_PACKED_PIXELS;
240 			info->fix.line_length = info->var.xres_virtual;
241 		}
242 	}
243 }
244 
245 static void vga16fb_clock_chip(struct vga16fb_par *par,
246 			       unsigned int *pixclock,
247 			       const struct fb_info *info,
248 			       int mul, int div)
249 {
250 	static const struct {
251 		u32 pixclock;
252 		u8  misc;
253 		u8  seq_clock_mode;
254 	} *ptr, *best, vgaclocks[] = {
255 		{ 79442 /* 12.587 */, 0x00, 0x08},
256 		{ 70616 /* 14.161 */, 0x04, 0x08},
257 		{ 39721 /* 25.175 */, 0x00, 0x00},
258 		{ 35308 /* 28.322 */, 0x04, 0x00},
259 		{     0 /* bad */,    0x00, 0x00}};
260 	int err;
261 
262 	*pixclock = (*pixclock * mul) / div;
263 	best = vgaclocks;
264 	err = *pixclock - best->pixclock;
265 	if (err < 0) err = -err;
266 	for (ptr = vgaclocks + 1; ptr->pixclock; ptr++) {
267 		int tmp;
268 
269 		tmp = *pixclock - ptr->pixclock;
270 		if (tmp < 0) tmp = -tmp;
271 		if (tmp < err) {
272 			err = tmp;
273 			best = ptr;
274 		}
275 	}
276 	par->misc |= best->misc;
277 	par->clkdiv = best->seq_clock_mode;
278 	*pixclock = (best->pixclock * div) / mul;
279 }
280 
281 #define FAIL(X) return -EINVAL
282 
283 static int vga16fb_open(struct fb_info *info, int user)
284 {
285 	struct vga16fb_par *par = info->par;
286 
287 	if (!par->ref_count) {
288 		memset(&par->state, 0, sizeof(struct vgastate));
289 		par->state.flags = VGA_SAVE_FONTS | VGA_SAVE_MODE |
290 			VGA_SAVE_CMAP;
291 		save_vga(&par->state);
292 	}
293 	par->ref_count++;
294 
295 	return 0;
296 }
297 
298 static int vga16fb_release(struct fb_info *info, int user)
299 {
300 	struct vga16fb_par *par = info->par;
301 
302 	if (!par->ref_count)
303 		return -EINVAL;
304 
305 	if (par->ref_count == 1)
306 		restore_vga(&par->state);
307 	par->ref_count--;
308 
309 	return 0;
310 }
311 
312 static int vga16fb_check_var(struct fb_var_screeninfo *var,
313 			     struct fb_info *info)
314 {
315 	struct vga16fb_par *par = info->par;
316 	u32 xres, right, hslen, left, xtotal;
317 	u32 yres, lower, vslen, upper, ytotal;
318 	u32 vxres, xoffset, vyres, yoffset;
319 	u32 pos;
320 	u8 r7, rMode;
321 	int shift;
322 	int mode;
323 	u32 maxmem;
324 
325 	par->pel_msk = 0xFF;
326 
327 	if (var->bits_per_pixel == 4) {
328 		if (var->nonstd) {
329 			if (!par->isVGA)
330 				return -EINVAL;
331 			shift = 3;
332 			mode = MODE_SKIP4 | MODE_CFB;
333 			maxmem = 16384;
334 			par->pel_msk = 0x0F;
335 		} else {
336 			shift = 3;
337 			mode = 0;
338 			maxmem = 65536;
339 		}
340 	} else if (var->bits_per_pixel == 8) {
341 		if (!par->isVGA)
342 			return -EINVAL;	/* no support on EGA */
343 		shift = 2;
344 		if (var->nonstd) {
345 			mode = MODE_8BPP | MODE_CFB;
346 			maxmem = 65536;
347 		} else {
348 			mode = MODE_SKIP4 | MODE_8BPP | MODE_CFB;
349 			maxmem = 16384;
350 		}
351 	} else
352 		return -EINVAL;
353 
354 	xres = (var->xres + 7) & ~7;
355 	vxres = (var->xres_virtual + 0xF) & ~0xF;
356 	xoffset = (var->xoffset + 7) & ~7;
357 	left = (var->left_margin + 7) & ~7;
358 	right = (var->right_margin + 7) & ~7;
359 	hslen = (var->hsync_len + 7) & ~7;
360 
361 	if (vxres < xres)
362 		vxres = xres;
363 	if (xres + xoffset > vxres)
364 		xoffset = vxres - xres;
365 
366 	var->xres = xres;
367 	var->right_margin = right;
368 	var->hsync_len = hslen;
369 	var->left_margin = left;
370 	var->xres_virtual = vxres;
371 	var->xoffset = xoffset;
372 
373 	xres >>= shift;
374 	right >>= shift;
375 	hslen >>= shift;
376 	left >>= shift;
377 	vxres >>= shift;
378 	xtotal = xres + right + hslen + left;
379 	if (xtotal >= 256)
380 		FAIL("xtotal too big");
381 	if (hslen > 32)
382 		FAIL("hslen too big");
383 	if (right + hslen + left > 64)
384 		FAIL("hblank too big");
385 	par->crtc[VGA_CRTC_H_TOTAL] = xtotal - 5;
386 	par->crtc[VGA_CRTC_H_BLANK_START] = xres - 1;
387 	par->crtc[VGA_CRTC_H_DISP] = xres - 1;
388 	pos = xres + right;
389 	par->crtc[VGA_CRTC_H_SYNC_START] = pos;
390 	pos += hslen;
391 	par->crtc[VGA_CRTC_H_SYNC_END] = pos & 0x1F;
392 	pos += left - 2; /* blank_end + 2 <= total + 5 */
393 	par->crtc[VGA_CRTC_H_BLANK_END] = (pos & 0x1F) | 0x80;
394 	if (pos & 0x20)
395 		par->crtc[VGA_CRTC_H_SYNC_END] |= 0x80;
396 
397 	yres = var->yres;
398 	lower = var->lower_margin;
399 	vslen = var->vsync_len;
400 	upper = var->upper_margin;
401 	vyres = var->yres_virtual;
402 	yoffset = var->yoffset;
403 
404 	if (yres > vyres)
405 		vyres = yres;
406 	if (vxres * vyres > maxmem) {
407 		vyres = maxmem / vxres;
408 		if (vyres < yres)
409 			return -ENOMEM;
410 	}
411 	if (yoffset + yres > vyres)
412 		yoffset = vyres - yres;
413 	var->yres = yres;
414 	var->lower_margin = lower;
415 	var->vsync_len = vslen;
416 	var->upper_margin = upper;
417 	var->yres_virtual = vyres;
418 	var->yoffset = yoffset;
419 
420 	if (var->vmode & FB_VMODE_DOUBLE) {
421 		yres <<= 1;
422 		lower <<= 1;
423 		vslen <<= 1;
424 		upper <<= 1;
425 	}
426 	ytotal = yres + lower + vslen + upper;
427 	if (ytotal > 1024) {
428 		ytotal >>= 1;
429 		yres >>= 1;
430 		lower >>= 1;
431 		vslen >>= 1;
432 		upper >>= 1;
433 		rMode = 0x04;
434 	} else
435 		rMode = 0x00;
436 	if (ytotal > 1024)
437 		FAIL("ytotal too big");
438 	if (vslen > 16)
439 		FAIL("vslen too big");
440 	par->crtc[VGA_CRTC_V_TOTAL] = ytotal - 2;
441 	r7 = 0x10;	/* disable linecompare */
442 	if (ytotal & 0x100) r7 |= 0x01;
443 	if (ytotal & 0x200) r7 |= 0x20;
444 	par->crtc[VGA_CRTC_PRESET_ROW] = 0;
445 	par->crtc[VGA_CRTC_MAX_SCAN] = 0x40;	/* 1 scanline, no linecmp */
446 	if (var->vmode & FB_VMODE_DOUBLE)
447 		par->crtc[VGA_CRTC_MAX_SCAN] |= 0x80;
448 	par->crtc[VGA_CRTC_CURSOR_START] = 0x20;
449 	par->crtc[VGA_CRTC_CURSOR_END]   = 0x00;
450 	if ((mode & (MODE_CFB | MODE_8BPP)) == MODE_CFB)
451 		xoffset--;
452 	pos = yoffset * vxres + (xoffset >> shift);
453 	par->crtc[VGA_CRTC_START_HI]     = pos >> 8;
454 	par->crtc[VGA_CRTC_START_LO]     = pos & 0xFF;
455 	par->crtc[VGA_CRTC_CURSOR_HI]    = 0x00;
456 	par->crtc[VGA_CRTC_CURSOR_LO]    = 0x00;
457 	pos = yres - 1;
458 	par->crtc[VGA_CRTC_V_DISP_END] = pos & 0xFF;
459 	par->crtc[VGA_CRTC_V_BLANK_START] = pos & 0xFF;
460 	if (pos & 0x100)
461 		r7 |= 0x0A;	/* 0x02 -> DISP_END, 0x08 -> BLANK_START */
462 	if (pos & 0x200) {
463 		r7 |= 0x40;	/* 0x40 -> DISP_END */
464 		par->crtc[VGA_CRTC_MAX_SCAN] |= 0x20; /* BLANK_START */
465 	}
466 	pos += lower;
467 	par->crtc[VGA_CRTC_V_SYNC_START] = pos & 0xFF;
468 	if (pos & 0x100)
469 		r7 |= 0x04;
470 	if (pos & 0x200)
471 		r7 |= 0x80;
472 	pos += vslen;
473 	par->crtc[VGA_CRTC_V_SYNC_END] = (pos & 0x0F) & ~0x10; /* disabled IRQ */
474 	pos += upper - 1; /* blank_end + 1 <= ytotal + 2 */
475 	par->crtc[VGA_CRTC_V_BLANK_END] = pos & 0xFF; /* 0x7F for original VGA,
476                      but some SVGA chips requires all 8 bits to set */
477 	if (vxres >= 512)
478 		FAIL("vxres too long");
479 	par->crtc[VGA_CRTC_OFFSET] = vxres >> 1;
480 	if (mode & MODE_SKIP4)
481 		par->crtc[VGA_CRTC_UNDERLINE] = 0x5F;	/* 256, cfb8 */
482 	else
483 		par->crtc[VGA_CRTC_UNDERLINE] = 0x1F;	/* 16, vgap */
484 	par->crtc[VGA_CRTC_MODE] = rMode | ((mode & MODE_TEXT) ? 0xA3 : 0xE3);
485 	par->crtc[VGA_CRTC_LINE_COMPARE] = 0xFF;
486 	par->crtc[VGA_CRTC_OVERFLOW] = r7;
487 
488 	par->vss = 0x00;	/* 3DA */
489 
490 	par->misc = 0xE3;	/* enable CPU, ports 0x3Dx, positive sync */
491 	if (var->sync & FB_SYNC_HOR_HIGH_ACT)
492 		par->misc &= ~0x40;
493 	if (var->sync & FB_SYNC_VERT_HIGH_ACT)
494 		par->misc &= ~0x80;
495 
496 	par->mode = mode;
497 
498 	if (mode & MODE_8BPP)
499 		/* pixel clock == vga clock / 2 */
500 		vga16fb_clock_chip(par, &var->pixclock, info, 1, 2);
501 	else
502 		/* pixel clock == vga clock */
503 		vga16fb_clock_chip(par, &var->pixclock, info, 1, 1);
504 
505 	var->red.offset = var->green.offset = var->blue.offset =
506 	var->transp.offset = 0;
507 	var->red.length = var->green.length = var->blue.length =
508 		(par->isVGA) ? 6 : 2;
509 	var->transp.length = 0;
510 	var->activate = FB_ACTIVATE_NOW;
511 	var->height = -1;
512 	var->width = -1;
513 	var->accel_flags = 0;
514 	return 0;
515 }
516 #undef FAIL
517 
518 static int vga16fb_set_par(struct fb_info *info)
519 {
520 	struct vga16fb_par *par = info->par;
521 	u8 gdc[VGA_GFX_C];
522 	u8 seq[VGA_SEQ_C];
523 	u8 atc[VGA_ATT_C];
524 	int fh, i;
525 
526 	seq[VGA_SEQ_CLOCK_MODE] = 0x01 | par->clkdiv;
527 	if (par->mode & MODE_TEXT)
528 		seq[VGA_SEQ_PLANE_WRITE] = 0x03;
529 	else
530 		seq[VGA_SEQ_PLANE_WRITE] = 0x0F;
531 	seq[VGA_SEQ_CHARACTER_MAP] = 0x00;
532 	if (par->mode & MODE_TEXT)
533 		seq[VGA_SEQ_MEMORY_MODE] = 0x03;
534 	else if (par->mode & MODE_SKIP4)
535 		seq[VGA_SEQ_MEMORY_MODE] = 0x0E;
536 	else
537 		seq[VGA_SEQ_MEMORY_MODE] = 0x06;
538 
539 	gdc[VGA_GFX_SR_VALUE] = 0x00;
540 	gdc[VGA_GFX_SR_ENABLE] = 0x00;
541 	gdc[VGA_GFX_COMPARE_VALUE] = 0x00;
542 	gdc[VGA_GFX_DATA_ROTATE] = 0x00;
543 	gdc[VGA_GFX_PLANE_READ] = 0;
544 	if (par->mode & MODE_TEXT) {
545 		gdc[VGA_GFX_MODE] = 0x10;
546 		gdc[VGA_GFX_MISC] = 0x06;
547 	} else {
548 		if (par->mode & MODE_CFB)
549 			gdc[VGA_GFX_MODE] = 0x40;
550 		else
551 			gdc[VGA_GFX_MODE] = 0x00;
552 		gdc[VGA_GFX_MISC] = 0x05;
553 	}
554 	gdc[VGA_GFX_COMPARE_MASK] = 0x0F;
555 	gdc[VGA_GFX_BIT_MASK] = 0xFF;
556 
557 	for (i = 0x00; i < 0x10; i++)
558 		atc[i] = i;
559 	if (par->mode & MODE_TEXT)
560 		atc[VGA_ATC_MODE] = 0x04;
561 	else if (par->mode & MODE_8BPP)
562 		atc[VGA_ATC_MODE] = 0x41;
563 	else
564 		atc[VGA_ATC_MODE] = 0x81;
565 	atc[VGA_ATC_OVERSCAN] = 0x00;	/* 0 for EGA, 0xFF for VGA */
566 	atc[VGA_ATC_PLANE_ENABLE] = 0x0F;
567 	if (par->mode & MODE_8BPP)
568 		atc[VGA_ATC_PEL] = (info->var.xoffset & 3) << 1;
569 	else
570 		atc[VGA_ATC_PEL] = info->var.xoffset & 7;
571 	atc[VGA_ATC_COLOR_PAGE] = 0x00;
572 
573 	if (par->mode & MODE_TEXT) {
574 		fh = 16; // FIXME !!! Fudge font height.
575 		par->crtc[VGA_CRTC_MAX_SCAN] = (par->crtc[VGA_CRTC_MAX_SCAN]
576 					       & ~0x1F) | (fh - 1);
577 	}
578 
579 	vga_io_w(VGA_MIS_W, vga_io_r(VGA_MIS_R) | 0x01);
580 
581 	/* Enable graphics register modification */
582 	if (!par->isVGA) {
583 		vga_io_w(EGA_GFX_E0, 0x00);
584 		vga_io_w(EGA_GFX_E1, 0x01);
585 	}
586 
587 	/* update misc output register */
588 	vga_io_w(VGA_MIS_W, par->misc);
589 
590 	/* synchronous reset on */
591 	vga_io_wseq(0x00, 0x01);
592 
593 	if (par->isVGA)
594 		vga_io_w(VGA_PEL_MSK, par->pel_msk);
595 
596 	/* write sequencer registers */
597 	vga_io_wseq(VGA_SEQ_CLOCK_MODE, seq[VGA_SEQ_CLOCK_MODE] | 0x20);
598 	for (i = 2; i < VGA_SEQ_C; i++) {
599 		vga_io_wseq(i, seq[i]);
600 	}
601 
602 	/* synchronous reset off */
603 	vga_io_wseq(0x00, 0x03);
604 
605 	/* deprotect CRT registers 0-7 */
606 	vga_io_wcrt(VGA_CRTC_V_SYNC_END, par->crtc[VGA_CRTC_V_SYNC_END]);
607 
608 	/* write CRT registers */
609 	for (i = 0; i < VGA_CRTC_REGS; i++) {
610 		vga_io_wcrt(i, par->crtc[i]);
611 	}
612 
613 	/* write graphics controller registers */
614 	for (i = 0; i < VGA_GFX_C; i++) {
615 		vga_io_wgfx(i, gdc[i]);
616 	}
617 
618 	/* write attribute controller registers */
619 	for (i = 0; i < VGA_ATT_C; i++) {
620 		vga_io_r(VGA_IS1_RC);		/* reset flip-flop */
621 		vga_io_wattr(i, atc[i]);
622 	}
623 
624 	/* Wait for screen to stabilize. */
625 	mdelay(50);
626 
627 	vga_io_wseq(VGA_SEQ_CLOCK_MODE, seq[VGA_SEQ_CLOCK_MODE]);
628 
629 	vga_io_r(VGA_IS1_RC);
630 	vga_io_w(VGA_ATT_IW, 0x20);
631 
632 	vga16fb_update_fix(info);
633 	return 0;
634 }
635 
636 static void ega16_setpalette(int regno, unsigned red, unsigned green, unsigned blue)
637 {
638 	static const unsigned char map[] = { 000, 001, 010, 011 };
639 	int val;
640 
641 	if (regno >= 16)
642 		return;
643 	val = map[red>>14] | ((map[green>>14]) << 1) | ((map[blue>>14]) << 2);
644 	vga_io_r(VGA_IS1_RC);   /* ! 0x3BA */
645 	vga_io_wattr(regno, val);
646 	vga_io_r(VGA_IS1_RC);   /* some clones need it */
647 	vga_io_w(VGA_ATT_IW, 0x20); /* unblank screen */
648 }
649 
650 static void vga16_setpalette(int regno, unsigned red, unsigned green, unsigned blue)
651 {
652 	outb(regno,       VGA_PEL_IW);
653 	outb(red   >> 10, VGA_PEL_D);
654 	outb(green >> 10, VGA_PEL_D);
655 	outb(blue  >> 10, VGA_PEL_D);
656 }
657 
658 static int vga16fb_setcolreg(unsigned regno, unsigned red, unsigned green,
659 			     unsigned blue, unsigned transp,
660 			     struct fb_info *info)
661 {
662 	struct vga16fb_par *par = info->par;
663 	int gray;
664 
665 	/*
666 	 *  Set a single color register. The values supplied are
667 	 *  already rounded down to the hardware's capabilities
668 	 *  (according to the entries in the `var' structure). Return
669 	 *  != 0 for invalid regno.
670 	 */
671 
672 	if (regno >= 256)
673 		return 1;
674 
675 	gray = info->var.grayscale;
676 
677 	if (gray) {
678 		/* gray = 0.30*R + 0.59*G + 0.11*B */
679 		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
680 	}
681 	if (par->isVGA)
682 		vga16_setpalette(regno,red,green,blue);
683 	else
684 		ega16_setpalette(regno,red,green,blue);
685 	return 0;
686 }
687 
688 static int vga16fb_pan_display(struct fb_var_screeninfo *var,
689 			       struct fb_info *info)
690 {
691 	vga16fb_pan_var(info, var);
692 	return 0;
693 }
694 
695 /* The following VESA blanking code is taken from vgacon.c.  The VGA
696    blanking code was originally by Huang shi chao, and modified by
697    Christoph Rimek (chrimek@toppoint.de) and todd j. derr
698    (tjd@barefoot.org) for Linux. */
699 
700 static void vga_vesa_blank(struct vga16fb_par *par, int mode)
701 {
702 	unsigned char SeqCtrlIndex = vga_io_r(VGA_SEQ_I);
703 	unsigned char CrtCtrlIndex = vga_io_r(VGA_CRT_IC);
704 
705 	/* save original values of VGA controller registers */
706 	if(!par->vesa_blanked) {
707 		par->vga_state.CrtMiscIO = vga_io_r(VGA_MIS_R);
708 		//sti();
709 
710 		par->vga_state.HorizontalTotal = vga_io_rcrt(0x00);	/* HorizontalTotal */
711 		par->vga_state.HorizDisplayEnd = vga_io_rcrt(0x01);	/* HorizDisplayEnd */
712 		par->vga_state.StartHorizRetrace = vga_io_rcrt(0x04);	/* StartHorizRetrace */
713 		par->vga_state.EndHorizRetrace = vga_io_rcrt(0x05);	/* EndHorizRetrace */
714 		par->vga_state.Overflow = vga_io_rcrt(0x07);		/* Overflow */
715 		par->vga_state.StartVertRetrace = vga_io_rcrt(0x10);	/* StartVertRetrace */
716 		par->vga_state.EndVertRetrace = vga_io_rcrt(0x11);	/* EndVertRetrace */
717 		par->vga_state.ModeControl = vga_io_rcrt(0x17);	/* ModeControl */
718 		par->vga_state.ClockingMode = vga_io_rseq(0x01);	/* ClockingMode */
719 	}
720 
721 	/* assure that video is enabled */
722 	/* "0x20" is VIDEO_ENABLE_bit in register 01 of sequencer */
723 	vga_io_wseq(0x01, par->vga_state.ClockingMode | 0x20);
724 
725 	/* test for vertical retrace in process.... */
726 	if ((par->vga_state.CrtMiscIO & 0x80) == 0x80)
727 		vga_io_w(VGA_MIS_W, par->vga_state.CrtMiscIO & 0xef);
728 
729 	/*
730 	 * Set <End of vertical retrace> to minimum (0) and
731 	 * <Start of vertical Retrace> to maximum (incl. overflow)
732 	 * Result: turn off vertical sync (VSync) pulse.
733 	 */
734 	if (mode & FB_BLANK_VSYNC_SUSPEND) {
735 		vga_io_wcrt(VGA_CRTC_V_SYNC_START, 0xff);
736 		vga_io_wcrt(VGA_CRTC_V_SYNC_END, 0x40);
737 		/* bits 9,10 of vert. retrace */
738 		vga_io_wcrt(VGA_CRTC_OVERFLOW, par->vga_state.Overflow | 0x84);
739 	}
740 
741 	if (mode & FB_BLANK_HSYNC_SUSPEND) {
742 		/*
743 		 * Set <End of horizontal retrace> to minimum (0) and
744 		 *  <Start of horizontal Retrace> to maximum
745 		 * Result: turn off horizontal sync (HSync) pulse.
746 		 */
747 		vga_io_wcrt(VGA_CRTC_H_SYNC_START, 0xff);
748 		vga_io_wcrt(VGA_CRTC_H_SYNC_END, 0x00);
749 	}
750 
751 	/* restore both index registers */
752 	outb_p(SeqCtrlIndex, VGA_SEQ_I);
753 	outb_p(CrtCtrlIndex, VGA_CRT_IC);
754 }
755 
756 static void vga_vesa_unblank(struct vga16fb_par *par)
757 {
758 	unsigned char SeqCtrlIndex = vga_io_r(VGA_SEQ_I);
759 	unsigned char CrtCtrlIndex = vga_io_r(VGA_CRT_IC);
760 
761 	/* restore original values of VGA controller registers */
762 	vga_io_w(VGA_MIS_W, par->vga_state.CrtMiscIO);
763 
764 	/* HorizontalTotal */
765 	vga_io_wcrt(0x00, par->vga_state.HorizontalTotal);
766 	/* HorizDisplayEnd */
767 	vga_io_wcrt(0x01, par->vga_state.HorizDisplayEnd);
768 	/* StartHorizRetrace */
769 	vga_io_wcrt(0x04, par->vga_state.StartHorizRetrace);
770 	/* EndHorizRetrace */
771 	vga_io_wcrt(0x05, par->vga_state.EndHorizRetrace);
772 	/* Overflow */
773 	vga_io_wcrt(0x07, par->vga_state.Overflow);
774 	/* StartVertRetrace */
775 	vga_io_wcrt(0x10, par->vga_state.StartVertRetrace);
776 	/* EndVertRetrace */
777 	vga_io_wcrt(0x11, par->vga_state.EndVertRetrace);
778 	/* ModeControl */
779 	vga_io_wcrt(0x17, par->vga_state.ModeControl);
780 	/* ClockingMode */
781 	vga_io_wseq(0x01, par->vga_state.ClockingMode);
782 
783 	/* restore index/control registers */
784 	vga_io_w(VGA_SEQ_I, SeqCtrlIndex);
785 	vga_io_w(VGA_CRT_IC, CrtCtrlIndex);
786 }
787 
788 static void vga_pal_blank(void)
789 {
790 	int i;
791 
792 	for (i=0; i<16; i++) {
793 		outb_p(i, VGA_PEL_IW);
794 		outb_p(0, VGA_PEL_D);
795 		outb_p(0, VGA_PEL_D);
796 		outb_p(0, VGA_PEL_D);
797 	}
798 }
799 
800 /* 0 unblank, 1 blank, 2 no vsync, 3 no hsync, 4 off */
801 static int vga16fb_blank(int blank, struct fb_info *info)
802 {
803 	struct vga16fb_par *par = info->par;
804 
805 	switch (blank) {
806 	case FB_BLANK_UNBLANK:				/* Unblank */
807 		if (par->vesa_blanked) {
808 			vga_vesa_unblank(par);
809 			par->vesa_blanked = 0;
810 		}
811 		if (par->palette_blanked) {
812 			par->palette_blanked = 0;
813 		}
814 		break;
815 	case FB_BLANK_NORMAL:				/* blank */
816 		vga_pal_blank();
817 		par->palette_blanked = 1;
818 		break;
819 	default:			/* VESA blanking */
820 		vga_vesa_blank(par, blank);
821 		par->vesa_blanked = 1;
822 		break;
823 	}
824 	return 0;
825 }
826 
827 static void vga_8planes_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
828 {
829 	u32 dx = rect->dx, width = rect->width;
830         char oldindex = getindex();
831         char oldmode = setmode(0x40);
832         char oldmask = selectmask();
833         int line_ofs, height;
834         char oldop, oldsr;
835         char __iomem *where;
836 
837         dx /= 4;
838         where = info->screen_base + dx + rect->dy * info->fix.line_length;
839 
840         if (rect->rop == ROP_COPY) {
841                 oldop = setop(0);
842                 oldsr = setsr(0);
843 
844                 width /= 4;
845                 line_ofs = info->fix.line_length - width;
846                 setmask(0xff);
847 
848                 height = rect->height;
849 
850                 while (height--) {
851                         int x;
852 
853                         /* we can do memset... */
854                         for (x = width; x > 0; --x) {
855                                 writeb(rect->color, where);
856                                 where++;
857                         }
858                         where += line_ofs;
859                 }
860         } else {
861                 char oldcolor = setcolor(0xf);
862                 int y;
863 
864                 oldop = setop(0x18);
865                 oldsr = setsr(0xf);
866                 setmask(0x0F);
867                 for (y = 0; y < rect->height; y++) {
868                         rmw(where);
869                         rmw(where+1);
870                         where += info->fix.line_length;
871                 }
872                 setcolor(oldcolor);
873         }
874         setmask(oldmask);
875         setsr(oldsr);
876         setop(oldop);
877         setmode(oldmode);
878         setindex(oldindex);
879 }
880 
881 static void vga16fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
882 {
883 	int x, x2, y2, vxres, vyres, width, height, line_ofs;
884 	char __iomem *dst;
885 
886 	vxres = info->var.xres_virtual;
887 	vyres = info->var.yres_virtual;
888 
889 	if (!rect->width || !rect->height || rect->dx > vxres || rect->dy > vyres)
890 		return;
891 
892 	/* We could use hardware clipping but on many cards you get around
893 	 * hardware clipping by writing to framebuffer directly. */
894 
895 	x2 = rect->dx + rect->width;
896 	y2 = rect->dy + rect->height;
897 	x2 = x2 < vxres ? x2 : vxres;
898 	y2 = y2 < vyres ? y2 : vyres;
899 	width = x2 - rect->dx;
900 
901 	switch (info->fix.type) {
902 	case FB_TYPE_VGA_PLANES:
903 		if (info->fix.type_aux == FB_AUX_VGA_PLANES_VGA4) {
904 
905 			height = y2 - rect->dy;
906 			width = rect->width/8;
907 
908 			line_ofs = info->fix.line_length - width;
909 			dst = info->screen_base + (rect->dx/8) + rect->dy * info->fix.line_length;
910 
911 			switch (rect->rop) {
912 			case ROP_COPY:
913 				setmode(0);
914 				setop(0);
915 				setsr(0xf);
916 				setcolor(rect->color);
917 				selectmask();
918 
919 				setmask(0xff);
920 
921 				while (height--) {
922 					for (x = 0; x < width; x++) {
923 						writeb(0, dst);
924 						dst++;
925 					}
926 					dst += line_ofs;
927 				}
928 				break;
929 			case ROP_XOR:
930 				setmode(0);
931 				setop(0x18);
932 				setsr(0xf);
933 				setcolor(0xf);
934 				selectmask();
935 
936 				setmask(0xff);
937 				while (height--) {
938 					for (x = 0; x < width; x++) {
939 						rmw(dst);
940 						dst++;
941 					}
942 					dst += line_ofs;
943 				}
944 				break;
945 			}
946 		} else
947 			vga_8planes_fillrect(info, rect);
948 		break;
949 	case FB_TYPE_PACKED_PIXELS:
950 	default:
951 		cfb_fillrect(info, rect);
952 		break;
953 	}
954 }
955 
956 static void vga_8planes_copyarea(struct fb_info *info, const struct fb_copyarea *area)
957 {
958         char oldindex = getindex();
959         char oldmode = setmode(0x41);
960         char oldop = setop(0);
961         char oldsr = setsr(0xf);
962         int height, line_ofs, x;
963 	u32 sx, dx, width;
964 	char __iomem *dest;
965 	char __iomem *src;
966 
967         height = area->height;
968 
969         sx = area->sx / 4;
970         dx = area->dx / 4;
971         width = area->width / 4;
972 
973         if (area->dy < area->sy || (area->dy == area->sy && dx < sx)) {
974                 line_ofs = info->fix.line_length - width;
975                 dest = info->screen_base + dx + area->dy * info->fix.line_length;
976                 src = info->screen_base + sx + area->sy * info->fix.line_length;
977                 while (height--) {
978                         for (x = 0; x < width; x++) {
979                                 readb(src);
980                                 writeb(0, dest);
981                                 src++;
982                                 dest++;
983                         }
984                         src += line_ofs;
985                         dest += line_ofs;
986                 }
987         } else {
988                 line_ofs = info->fix.line_length - width;
989                 dest = info->screen_base + dx + width +
990 			(area->dy + height - 1) * info->fix.line_length;
991                 src = info->screen_base + sx + width +
992 			(area->sy + height - 1) * info->fix.line_length;
993                 while (height--) {
994                         for (x = 0; x < width; x++) {
995                                 --src;
996                                 --dest;
997                                 readb(src);
998                                 writeb(0, dest);
999                         }
1000                         src -= line_ofs;
1001                         dest -= line_ofs;
1002                 }
1003         }
1004 
1005         setsr(oldsr);
1006         setop(oldop);
1007         setmode(oldmode);
1008         setindex(oldindex);
1009 }
1010 
1011 static void vga16fb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
1012 {
1013 	u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy;
1014 	int x, x2, y2, old_dx, old_dy, vxres, vyres;
1015 	int height, width, line_ofs;
1016 	char __iomem *dst = NULL;
1017 	char __iomem *src = NULL;
1018 
1019 	vxres = info->var.xres_virtual;
1020 	vyres = info->var.yres_virtual;
1021 
1022 	if (area->dx > vxres || area->sx > vxres || area->dy > vyres ||
1023 	    area->sy > vyres)
1024 		return;
1025 
1026 	/* clip the destination */
1027 	old_dx = area->dx;
1028 	old_dy = area->dy;
1029 
1030 	/*
1031 	 * We could use hardware clipping but on many cards you get around
1032 	 * hardware clipping by writing to framebuffer directly.
1033 	 */
1034 	x2 = area->dx + area->width;
1035 	y2 = area->dy + area->height;
1036 	dx = area->dx > 0 ? area->dx : 0;
1037 	dy = area->dy > 0 ? area->dy : 0;
1038 	x2 = x2 < vxres ? x2 : vxres;
1039 	y2 = y2 < vyres ? y2 : vyres;
1040 	width = x2 - dx;
1041 	height = y2 - dy;
1042 
1043 	if (sx + dx < old_dx || sy + dy < old_dy)
1044 		return;
1045 
1046 	/* update sx1,sy1 */
1047 	sx += (dx - old_dx);
1048 	sy += (dy - old_dy);
1049 
1050 	/* the source must be completely inside the virtual screen */
1051 	if (sx + width > vxres || sy + height > vyres)
1052 		return;
1053 
1054 	switch (info->fix.type) {
1055 	case FB_TYPE_VGA_PLANES:
1056 		if (info->fix.type_aux == FB_AUX_VGA_PLANES_VGA4) {
1057 			width = width/8;
1058 			line_ofs = info->fix.line_length - width;
1059 
1060 			setmode(1);
1061 			setop(0);
1062 			setsr(0xf);
1063 
1064 			if (dy < sy || (dy == sy && dx < sx)) {
1065 				dst = info->screen_base + (dx/8) + dy * info->fix.line_length;
1066 				src = info->screen_base + (sx/8) + sy * info->fix.line_length;
1067 				while (height--) {
1068 					for (x = 0; x < width; x++) {
1069 						readb(src);
1070 						writeb(0, dst);
1071 						dst++;
1072 						src++;
1073 					}
1074 					src += line_ofs;
1075 					dst += line_ofs;
1076 				}
1077 			} else {
1078 				dst = info->screen_base + (dx/8) + width +
1079 					(dy + height - 1) * info->fix.line_length;
1080 				src = info->screen_base + (sx/8) + width +
1081 					(sy + height  - 1) * info->fix.line_length;
1082 				while (height--) {
1083 					for (x = 0; x < width; x++) {
1084 						dst--;
1085 						src--;
1086 						readb(src);
1087 						writeb(0, dst);
1088 					}
1089 					src -= line_ofs;
1090 					dst -= line_ofs;
1091 				}
1092 			}
1093 		} else
1094 			vga_8planes_copyarea(info, area);
1095 		break;
1096 	case FB_TYPE_PACKED_PIXELS:
1097 	default:
1098 		cfb_copyarea(info, area);
1099 		break;
1100 	}
1101 }
1102 
1103 #define TRANS_MASK_LOW  {0x0,0x8,0x4,0xC,0x2,0xA,0x6,0xE,0x1,0x9,0x5,0xD,0x3,0xB,0x7,0xF}
1104 #define TRANS_MASK_HIGH {0x000, 0x800, 0x400, 0xC00, 0x200, 0xA00, 0x600, 0xE00, \
1105 			 0x100, 0x900, 0x500, 0xD00, 0x300, 0xB00, 0x700, 0xF00}
1106 
1107 #if defined(__LITTLE_ENDIAN)
1108 static const u16 transl_l[] = TRANS_MASK_LOW;
1109 static const u16 transl_h[] = TRANS_MASK_HIGH;
1110 #elif defined(__BIG_ENDIAN)
1111 static const u16 transl_l[] = TRANS_MASK_HIGH;
1112 static const u16 transl_h[] = TRANS_MASK_LOW;
1113 #else
1114 #error "Only __BIG_ENDIAN and __LITTLE_ENDIAN are supported in vga-planes"
1115 #endif
1116 
1117 static void vga_8planes_imageblit(struct fb_info *info, const struct fb_image *image)
1118 {
1119         char oldindex = getindex();
1120         char oldmode = setmode(0x40);
1121         char oldop = setop(0);
1122         char oldsr = setsr(0);
1123         char oldmask = selectmask();
1124 	const unsigned char *cdat = image->data;
1125 	u32 dx = image->dx;
1126         char __iomem *where;
1127         int y;
1128 
1129         dx /= 4;
1130         where = info->screen_base + dx + image->dy * info->fix.line_length;
1131 
1132         setmask(0xff);
1133         writeb(image->bg_color, where);
1134         readb(where);
1135         selectmask();
1136         setmask(image->fg_color ^ image->bg_color);
1137         setmode(0x42);
1138         setop(0x18);
1139         for (y = 0; y < image->height; y++, where += info->fix.line_length)
1140                 writew(transl_h[cdat[y]&0xF] | transl_l[cdat[y] >> 4], where);
1141         setmask(oldmask);
1142         setsr(oldsr);
1143         setop(oldop);
1144         setmode(oldmode);
1145         setindex(oldindex);
1146 }
1147 
1148 static void vga_imageblit_expand(struct fb_info *info, const struct fb_image *image)
1149 {
1150 	char __iomem *where = info->screen_base + (image->dx/8) +
1151 		image->dy * info->fix.line_length;
1152 	struct vga16fb_par *par = info->par;
1153 	char *cdat = (char *) image->data;
1154 	char __iomem *dst;
1155 	int x, y;
1156 
1157 	switch (info->fix.type) {
1158 	case FB_TYPE_VGA_PLANES:
1159 		if (info->fix.type_aux == FB_AUX_VGA_PLANES_VGA4) {
1160 			if (par->isVGA) {
1161 				setmode(2);
1162 				setop(0);
1163 				setsr(0xf);
1164 				setcolor(image->fg_color);
1165 				selectmask();
1166 
1167 				setmask(0xff);
1168 				writeb(image->bg_color, where);
1169 				rmb();
1170 				readb(where); /* fill latches */
1171 				setmode(3);
1172 				wmb();
1173 				for (y = 0; y < image->height; y++) {
1174 					dst = where;
1175 					for (x = image->width/8; x--;)
1176 						writeb(*cdat++, dst++);
1177 					where += info->fix.line_length;
1178 				}
1179 				wmb();
1180 			} else {
1181 				setmode(0);
1182 				setop(0);
1183 				setsr(0xf);
1184 				setcolor(image->bg_color);
1185 				selectmask();
1186 
1187 				setmask(0xff);
1188 				for (y = 0; y < image->height; y++) {
1189 					dst = where;
1190 					for (x=image->width/8; x--;){
1191 						rmw(dst);
1192 						setcolor(image->fg_color);
1193 						selectmask();
1194 						if (*cdat) {
1195 							setmask(*cdat++);
1196 							rmw(dst++);
1197 						}
1198 					}
1199 					where += info->fix.line_length;
1200 				}
1201 			}
1202 		} else
1203 			vga_8planes_imageblit(info, image);
1204 		break;
1205 	case FB_TYPE_PACKED_PIXELS:
1206 	default:
1207 		cfb_imageblit(info, image);
1208 		break;
1209 	}
1210 }
1211 
1212 static void vga_imageblit_color(struct fb_info *info, const struct fb_image *image)
1213 {
1214 	/*
1215 	 * Draw logo
1216 	 */
1217 	struct vga16fb_par *par = info->par;
1218 	char __iomem *where =
1219 		info->screen_base + image->dy * info->fix.line_length +
1220 		image->dx/8;
1221 	const char *cdat = image->data;
1222 	char __iomem *dst;
1223 	int x, y;
1224 
1225 	switch (info->fix.type) {
1226 	case FB_TYPE_VGA_PLANES:
1227 		if (info->fix.type_aux == FB_AUX_VGA_PLANES_VGA4 &&
1228 		    par->isVGA) {
1229 			setsr(0xf);
1230 			setop(0);
1231 			setmode(0);
1232 
1233 			for (y = 0; y < image->height; y++) {
1234 				for (x = 0; x < image->width; x++) {
1235 					dst = where + x/8;
1236 
1237 					setcolor(*cdat);
1238 					selectmask();
1239 					setmask(1 << (7 - (x % 8)));
1240 					fb_readb(dst);
1241 					fb_writeb(0, dst);
1242 
1243 					cdat++;
1244 				}
1245 				where += info->fix.line_length;
1246 			}
1247 		}
1248 		break;
1249 	case FB_TYPE_PACKED_PIXELS:
1250 		cfb_imageblit(info, image);
1251 		break;
1252 	default:
1253 		break;
1254 	}
1255 }
1256 
1257 static void vga16fb_imageblit(struct fb_info *info, const struct fb_image *image)
1258 {
1259 	if (image->depth == 1)
1260 		vga_imageblit_expand(info, image);
1261 	else
1262 		vga_imageblit_color(info, image);
1263 }
1264 
1265 static void vga16fb_destroy(struct fb_info *info)
1266 {
1267 	iounmap(info->screen_base);
1268 	fb_dealloc_cmap(&info->cmap);
1269 	/* XXX unshare VGA regions */
1270 	framebuffer_release(info);
1271 }
1272 
1273 static const struct fb_ops vga16fb_ops = {
1274 	.owner		= THIS_MODULE,
1275 	.fb_open        = vga16fb_open,
1276 	.fb_release     = vga16fb_release,
1277 	.fb_destroy	= vga16fb_destroy,
1278 	.fb_check_var	= vga16fb_check_var,
1279 	.fb_set_par	= vga16fb_set_par,
1280 	.fb_setcolreg 	= vga16fb_setcolreg,
1281 	.fb_pan_display = vga16fb_pan_display,
1282 	.fb_blank 	= vga16fb_blank,
1283 	.fb_fillrect	= vga16fb_fillrect,
1284 	.fb_copyarea	= vga16fb_copyarea,
1285 	.fb_imageblit	= vga16fb_imageblit,
1286 };
1287 
1288 #ifndef MODULE
1289 static int __init vga16fb_setup(char *options)
1290 {
1291 	char *this_opt;
1292 
1293 	if (!options || !*options)
1294 		return 0;
1295 
1296 	while ((this_opt = strsep(&options, ",")) != NULL) {
1297 		if (!*this_opt) continue;
1298 	}
1299 	return 0;
1300 }
1301 #endif
1302 
1303 static int vga16fb_probe(struct platform_device *dev)
1304 {
1305 	struct fb_info *info;
1306 	struct vga16fb_par *par;
1307 	int i;
1308 	int ret = 0;
1309 
1310 	printk(KERN_DEBUG "vga16fb: initializing\n");
1311 	info = framebuffer_alloc(sizeof(struct vga16fb_par), &dev->dev);
1312 
1313 	if (!info) {
1314 		ret = -ENOMEM;
1315 		goto err_fb_alloc;
1316 	}
1317 	info->apertures = alloc_apertures(1);
1318 	if (!info->apertures) {
1319 		ret = -ENOMEM;
1320 		goto err_ioremap;
1321 	}
1322 
1323 	/* XXX share VGA_FB_PHYS and I/O region with vgacon and others */
1324 	info->screen_base = (void __iomem *)VGA_MAP_MEM(VGA_FB_PHYS, 0);
1325 
1326 	if (!info->screen_base) {
1327 		printk(KERN_ERR "vga16fb: unable to map device\n");
1328 		ret = -ENOMEM;
1329 		goto err_ioremap;
1330 	}
1331 
1332 	printk(KERN_INFO "vga16fb: mapped to 0x%p\n", info->screen_base);
1333 	par = info->par;
1334 
1335 #if defined(CONFIG_X86)
1336 	par->isVGA = screen_info.orig_video_isVGA == VIDEO_TYPE_VGAC;
1337 #else
1338 	/* non-x86 architectures treat orig_video_isVGA as a boolean flag */
1339 	par->isVGA = screen_info.orig_video_isVGA;
1340 #endif
1341 	par->palette_blanked = 0;
1342 	par->vesa_blanked = 0;
1343 
1344 	i = par->isVGA? 6 : 2;
1345 
1346 	vga16fb_defined.red.length   = i;
1347 	vga16fb_defined.green.length = i;
1348 	vga16fb_defined.blue.length  = i;
1349 
1350 	/* name should not depend on EGA/VGA */
1351 	info->fbops = &vga16fb_ops;
1352 	info->var = vga16fb_defined;
1353 	info->fix = vga16fb_fix;
1354 	/* supports rectangles with widths of multiples of 8 */
1355 	info->pixmap.blit_x = 1 << 7 | 1 << 15 | 1 << 23 | 1 << 31;
1356 	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE |
1357 		FBINFO_HWACCEL_YPAN;
1358 
1359 	i = (info->var.bits_per_pixel == 8) ? 256 : 16;
1360 	ret = fb_alloc_cmap(&info->cmap, i, 0);
1361 	if (ret) {
1362 		printk(KERN_ERR "vga16fb: unable to allocate colormap\n");
1363 		ret = -ENOMEM;
1364 		goto err_alloc_cmap;
1365 	}
1366 
1367 	if (vga16fb_check_var(&info->var, info)) {
1368 		printk(KERN_ERR "vga16fb: unable to validate variable\n");
1369 		ret = -EINVAL;
1370 		goto err_check_var;
1371 	}
1372 
1373 	vga16fb_update_fix(info);
1374 
1375 	info->apertures->ranges[0].base = VGA_FB_PHYS;
1376 	info->apertures->ranges[0].size = VGA_FB_PHYS_LEN;
1377 
1378 	if (register_framebuffer(info) < 0) {
1379 		printk(KERN_ERR "vga16fb: unable to register framebuffer\n");
1380 		ret = -EINVAL;
1381 		goto err_check_var;
1382 	}
1383 
1384 	fb_info(info, "%s frame buffer device\n", info->fix.id);
1385 	platform_set_drvdata(dev, info);
1386 
1387 	return 0;
1388 
1389  err_check_var:
1390 	fb_dealloc_cmap(&info->cmap);
1391  err_alloc_cmap:
1392 	iounmap(info->screen_base);
1393  err_ioremap:
1394 	framebuffer_release(info);
1395  err_fb_alloc:
1396 	return ret;
1397 }
1398 
1399 static int vga16fb_remove(struct platform_device *dev)
1400 {
1401 	struct fb_info *info = platform_get_drvdata(dev);
1402 
1403 	if (info)
1404 		unregister_framebuffer(info);
1405 
1406 	return 0;
1407 }
1408 
1409 static struct platform_driver vga16fb_driver = {
1410 	.probe = vga16fb_probe,
1411 	.remove = vga16fb_remove,
1412 	.driver = {
1413 		.name = "vga16fb",
1414 	},
1415 };
1416 
1417 static struct platform_device *vga16fb_device;
1418 
1419 static int __init vga16fb_init(void)
1420 {
1421 	int ret;
1422 #ifndef MODULE
1423 	char *option = NULL;
1424 
1425 	if (fb_get_options("vga16fb", &option))
1426 		return -ENODEV;
1427 
1428 	vga16fb_setup(option);
1429 #endif
1430 	ret = platform_driver_register(&vga16fb_driver);
1431 
1432 	if (!ret) {
1433 		vga16fb_device = platform_device_alloc("vga16fb", 0);
1434 
1435 		if (vga16fb_device)
1436 			ret = platform_device_add(vga16fb_device);
1437 		else
1438 			ret = -ENOMEM;
1439 
1440 		if (ret) {
1441 			platform_device_put(vga16fb_device);
1442 			platform_driver_unregister(&vga16fb_driver);
1443 		}
1444 	}
1445 
1446 	return ret;
1447 }
1448 
1449 static void __exit vga16fb_exit(void)
1450 {
1451 	platform_device_unregister(vga16fb_device);
1452 	platform_driver_unregister(&vga16fb_driver);
1453 }
1454 
1455 MODULE_DESCRIPTION("Legacy VGA framebuffer device driver");
1456 MODULE_LICENSE("GPL");
1457 module_init(vga16fb_init);
1458 module_exit(vga16fb_exit);
1459