Free Electrons

Embedded Linux Experts

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
/*
 * linux/drivers/video/hgafb.c -- Hercules graphics adaptor frame buffer device
 * 
 *      Created 25 Nov 1999 by Ferenc Bakonyi (fero@drama.obuda.kando.hu)
 *      Based on skeletonfb.c by Geert Uytterhoeven and
 *               mdacon.c by Andrew Apted
 *
 * History:
 *
 * - Revision 0.1.8 (23 Oct 2002): Ported to new framebuffer api.
 * 
 * - Revision 0.1.7 (23 Jan 2001): fix crash resulting from MDA only cards 
 *				   being detected as Hercules.	 (Paul G.)
 * - Revision 0.1.6 (17 Aug 2000): new style structs
 *                                 documentation
 * - Revision 0.1.5 (13 Mar 2000): spinlocks instead of saveflags();cli();etc
 *                                 minor fixes
 * - Revision 0.1.4 (24 Jan 2000): fixed a bug in hga_card_detect() for 
 *                                  HGA-only systems
 * - Revision 0.1.3 (22 Jan 2000): modified for the new fb_info structure
 *                                 screen is cleared after rmmod
 *                                 virtual resolutions
 *                                 module parameter 'nologo={0|1}'
 *                                 the most important: boot logo :)
 * - Revision 0.1.0  (6 Dec 1999): faster scrolling and minor fixes
 * - First release  (25 Nov 1999)
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file COPYING in the main directory of this archive
 * for more details.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <asm/io.h>
#include <asm/vga.h>

#if 0
#define DPRINTK(args...) printk(KERN_DEBUG __FILE__": " ##args)
#else
#define DPRINTK(args...)
#endif

#if 0
#define CHKINFO(ret) if (info != &fb_info) { printk(KERN_DEBUG __FILE__": This should never happen, line:%d \n", __LINE__); return ret; }
#else
#define CHKINFO(ret)
#endif

/* Description of the hardware layout */

static void __iomem *hga_vram;			/* Base of video memory */
static unsigned long hga_vram_len;		/* Size of video memory */

#define HGA_ROWADDR(row) ((row%4)*8192 + (row>>2)*90)
#define HGA_TXT			0
#define HGA_GFX			1

static inline u8 __iomem * rowaddr(struct fb_info *info, u_int row)
{
	return info->screen_base + HGA_ROWADDR(row);
}

static int hga_mode = -1;			/* 0 = txt, 1 = gfx mode */

static enum { TYPE_HERC, TYPE_HERCPLUS, TYPE_HERCCOLOR } hga_type;
static char *hga_type_name;

#define HGA_INDEX_PORT		0x3b4		/* Register select port */
#define HGA_VALUE_PORT		0x3b5		/* Register value port */
#define HGA_MODE_PORT		0x3b8		/* Mode control port */
#define HGA_STATUS_PORT		0x3ba		/* Status and Config port */
#define HGA_GFX_PORT		0x3bf		/* Graphics control port */

/* HGA register values */

#define HGA_CURSOR_BLINKING	0x00
#define HGA_CURSOR_OFF		0x20
#define HGA_CURSOR_SLOWBLINK	0x60

#define HGA_MODE_GRAPHICS	0x02
#define HGA_MODE_VIDEO_EN	0x08
#define HGA_MODE_BLINK_EN	0x20
#define HGA_MODE_GFX_PAGE1	0x80

#define HGA_STATUS_HSYNC	0x01
#define HGA_STATUS_VSYNC	0x80
#define HGA_STATUS_VIDEO	0x08

#define HGA_CONFIG_COL132	0x08
#define HGA_GFX_MODE_EN		0x01
#define HGA_GFX_PAGE_EN		0x02

/* Global locks */

static DEFINE_SPINLOCK(hga_reg_lock);

/* Framebuffer driver structures */

static const struct fb_var_screeninfo hga_default_var = {
	.xres		= 720,
	.yres 		= 348,
	.xres_virtual 	= 720,
	.yres_virtual	= 348,
	.bits_per_pixel = 1,
	.red 		= {0, 1, 0},
	.green 		= {0, 1, 0},
	.blue 		= {0, 1, 0},
	.transp 	= {0, 0, 0},
	.height 	= -1,
	.width 		= -1,
};

static struct fb_fix_screeninfo hga_fix = {
	.id 		= "HGA",
	.type 		= FB_TYPE_PACKED_PIXELS,	/* (not sure) */
	.visual 	= FB_VISUAL_MONO10,
	.xpanstep 	= 8,
	.ypanstep 	= 8,
	.line_length 	= 90,
	.accel 		= FB_ACCEL_NONE
};

/* Don't assume that tty1 will be the initial current console. */
static int release_io_port = 0;
static int release_io_ports = 0;
static bool nologo = 0;

/* -------------------------------------------------------------------------
 *
 * Low level hardware functions
 *
 * ------------------------------------------------------------------------- */

static void write_hga_b(unsigned int val, unsigned char reg)
{
	outb_p(reg, HGA_INDEX_PORT); 
	outb_p(val, HGA_VALUE_PORT);
}

static void write_hga_w(unsigned int val, unsigned char reg)
{
	outb_p(reg,   HGA_INDEX_PORT); outb_p(val >> 8,   HGA_VALUE_PORT);
	outb_p(reg+1, HGA_INDEX_PORT); outb_p(val & 0xff, HGA_VALUE_PORT);
}

static int test_hga_b(unsigned char val, unsigned char reg)
{
	outb_p(reg, HGA_INDEX_PORT); 
	outb  (val, HGA_VALUE_PORT);
	udelay(20); val = (inb_p(HGA_VALUE_PORT) == val);
	return val;
}

static void hga_clear_screen(void)
{
	unsigned char fillchar = 0xbf; /* magic */
	unsigned long flags;

	spin_lock_irqsave(&hga_reg_lock, flags);
	if (hga_mode == HGA_TXT)
		fillchar = ' ';
	else if (hga_mode == HGA_GFX)
		fillchar = 0x00;
	spin_unlock_irqrestore(&hga_reg_lock, flags);
	if (fillchar != 0xbf)
		memset_io(hga_vram, fillchar, hga_vram_len);
}

static void hga_txt_mode(void)
{
	unsigned long flags;

	spin_lock_irqsave(&hga_reg_lock, flags);
	outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_BLINK_EN, HGA_MODE_PORT);
	outb_p(0x00, HGA_GFX_PORT);
	outb_p(0x00, HGA_STATUS_PORT);

	write_hga_b(0x61, 0x00);	/* horizontal total */
	write_hga_b(0x50, 0x01);	/* horizontal displayed */
	write_hga_b(0x52, 0x02);	/* horizontal sync pos */
	write_hga_b(0x0f, 0x03);	/* horizontal sync width */

	write_hga_b(0x19, 0x04);	/* vertical total */
	write_hga_b(0x06, 0x05);	/* vertical total adjust */
	write_hga_b(0x19, 0x06);	/* vertical displayed */
	write_hga_b(0x19, 0x07);	/* vertical sync pos */

	write_hga_b(0x02, 0x08);	/* interlace mode */
	write_hga_b(0x0d, 0x09);	/* maximum scanline */
	write_hga_b(0x0c, 0x0a);	/* cursor start */
	write_hga_b(0x0d, 0x0b);	/* cursor end */

	write_hga_w(0x0000, 0x0c);	/* start address */
	write_hga_w(0x0000, 0x0e);	/* cursor location */

	hga_mode = HGA_TXT;
	spin_unlock_irqrestore(&hga_reg_lock, flags);
}

static void hga_gfx_mode(void)
{
	unsigned long flags;

	spin_lock_irqsave(&hga_reg_lock, flags);
	outb_p(0x00, HGA_STATUS_PORT);
	outb_p(HGA_GFX_MODE_EN, HGA_GFX_PORT);
	outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_GRAPHICS, HGA_MODE_PORT);

	write_hga_b(0x35, 0x00);	/* horizontal total */
	write_hga_b(0x2d, 0x01);	/* horizontal displayed */
	write_hga_b(0x2e, 0x02);	/* horizontal sync pos */
	write_hga_b(0x07, 0x03);	/* horizontal sync width */

	write_hga_b(0x5b, 0x04);	/* vertical total */
	write_hga_b(0x02, 0x05);	/* vertical total adjust */
	write_hga_b(0x57, 0x06);	/* vertical displayed */
	write_hga_b(0x57, 0x07);	/* vertical sync pos */

	write_hga_b(0x02, 0x08);	/* interlace mode */
	write_hga_b(0x03, 0x09);	/* maximum scanline */
	write_hga_b(0x00, 0x0a);	/* cursor start */
	write_hga_b(0x00, 0x0b);	/* cursor end */

	write_hga_w(0x0000, 0x0c);	/* start address */
	write_hga_w(0x0000, 0x0e);	/* cursor location */

	hga_mode = HGA_GFX;
	spin_unlock_irqrestore(&hga_reg_lock, flags);
}

static void hga_show_logo(struct fb_info *info)
{
/*
	void __iomem *dest = hga_vram;
	char *logo = linux_logo_bw;
	int x, y;
	
	for (y = 134; y < 134 + 80 ; y++) * this needs some cleanup *
		for (x = 0; x < 10 ; x++)
			writeb(~*(logo++),(dest + HGA_ROWADDR(y) + x + 40));
*/
}

static void hga_pan(unsigned int xoffset, unsigned int yoffset)
{
	unsigned int base;
	unsigned long flags;
	
	base = (yoffset / 8) * 90 + xoffset;
	spin_lock_irqsave(&hga_reg_lock, flags);
	write_hga_w(base, 0x0c);	/* start address */
	spin_unlock_irqrestore(&hga_reg_lock, flags);
	DPRINTK("hga_pan: base:%d\n", base);
}

static void hga_blank(int blank_mode)
{
	unsigned long flags;

	spin_lock_irqsave(&hga_reg_lock, flags);
	if (blank_mode) {
		outb_p(0x00, HGA_MODE_PORT);	/* disable video */
	} else {
		outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_GRAPHICS, HGA_MODE_PORT);
	}
	spin_unlock_irqrestore(&hga_reg_lock, flags);
}

static int hga_card_detect(void)
{
	int count = 0;
	void __iomem *p, *q;
	unsigned short p_save, q_save;

	hga_vram_len  = 0x08000;

	hga_vram = ioremap(0xb0000, hga_vram_len);

	if (request_region(0x3b0, 12, "hgafb"))
		release_io_ports = 1;
	if (request_region(0x3bf, 1, "hgafb"))
		release_io_port = 1;

	/* do a memory check */

	p = hga_vram;
	q = hga_vram + 0x01000;

	p_save = readw(p); q_save = readw(q);

	writew(0xaa55, p); if (readw(p) == 0xaa55) count++;
	writew(0x55aa, p); if (readw(p) == 0x55aa) count++;
	writew(p_save, p);

	if (count != 2)
		goto error;

	/* Ok, there is definitely a card registering at the correct
	 * memory location, so now we do an I/O port test.
	 */
	
	if (!test_hga_b(0x66, 0x0f))	    /* cursor low register */
		goto error;

	if (!test_hga_b(0x99, 0x0f))     /* cursor low register */
		goto error;

	/* See if the card is a Hercules, by checking whether the vsync
	 * bit of the status register is changing.  This test lasts for
	 * approximately 1/10th of a second.
	 */
	
	p_save = q_save = inb_p(HGA_STATUS_PORT) & HGA_STATUS_VSYNC;

	for (count=0; count < 50000 && p_save == q_save; count++) {
		q_save = inb(HGA_STATUS_PORT) & HGA_STATUS_VSYNC;
		udelay(2);
	}

	if (p_save == q_save) 
		goto error;

	switch (inb_p(HGA_STATUS_PORT) & 0x70) {
		case 0x10:
			hga_type = TYPE_HERCPLUS;
			hga_type_name = "HerculesPlus";
			break;
		case 0x50:
			hga_type = TYPE_HERCCOLOR;
			hga_type_name = "HerculesColor";
			break;
		default:
			hga_type = TYPE_HERC;
			hga_type_name = "Hercules";
			break;
	}
	return 1;
error:
	if (release_io_ports)
		release_region(0x3b0, 12);
	if (release_io_port)
		release_region(0x3bf, 1);
	return 0;
}

/**
 *	hgafb_open - open the framebuffer device
 *	@info:pointer to fb_info object containing info for current hga board
 *	@int:open by console system or userland.
 */

static int hgafb_open(struct fb_info *info, int init)
{
	hga_gfx_mode();
	hga_clear_screen();
	if (!nologo) hga_show_logo(info);
	return 0;
}

/**
 *	hgafb_open - open the framebuffer device
 *	@info:pointer to fb_info object containing info for current hga board
 *	@int:open by console system or userland.
 */

static int hgafb_release(struct fb_info *info, int init)
{
	hga_txt_mode();
	hga_clear_screen();
	return 0;
}

/**
 *	hgafb_setcolreg - set color registers
 *	@regno:register index to set
 *	@red:red value, unused
 *	@green:green value, unused
 *	@blue:blue value, unused
 *	@transp:transparency value, unused
 *	@info:unused
 *
 *	This callback function is used to set the color registers of a HGA
 *	board. Since we have only two fixed colors only @regno is checked.
 *	A zero is returned on success and 1 for failure.
 */

static int hgafb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			   u_int transp, struct fb_info *info)
{
	if (regno > 1)
		return 1;
	return 0;
}

/**
 *	hga_pan_display - pan or wrap the display
 *	@var:contains new xoffset, yoffset and vmode values
 *	@info:pointer to fb_info object containing info for current hga board
 *
 *	This function looks only at xoffset, yoffset and the %FB_VMODE_YWRAP
 *	flag in @var. If input parameters are correct it calls hga_pan() to 
 *	program the hardware. @info->var is updated to the new values.
 *	A zero is returned on success and %-EINVAL for failure.
 */

static int hgafb_pan_display(struct fb_var_screeninfo *var,
			     struct fb_info *info)
{
	if (var->vmode & FB_VMODE_YWRAP) {
		if (var->yoffset >= info->var.yres_virtual ||
		    var->xoffset)
			return -EINVAL;
	} else {
		if (var->xoffset + info->var.xres > info->var.xres_virtual
		 || var->yoffset + info->var.yres > info->var.yres_virtual
		 || var->yoffset % 8)
			return -EINVAL;
	}

	hga_pan(var->xoffset, var->yoffset);
	return 0;
}

/**
 *	hgafb_blank - (un)blank the screen
 *	@blank_mode:blanking method to use
 *	@info:unused
 *	
 *	Blank the screen if blank_mode != 0, else unblank. 
 *	Implements VESA suspend and powerdown modes on hardware that supports 
 *	disabling hsync/vsync:
 *		@blank_mode == 2 means suspend vsync,
 *		@blank_mode == 3 means suspend hsync,
 *		@blank_mode == 4 means powerdown.
 */

static int hgafb_blank(int blank_mode, struct fb_info *info)
{
	hga_blank(blank_mode);
	return 0;
}

/*
 * Accel functions
 */
static void hgafb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
{
	u_int rows, y;
	u8 __iomem *dest;

	y = rect->dy;

	for (rows = rect->height; rows--; y++) {
		dest = rowaddr(info, y) + (rect->dx >> 3);
		switch (rect->rop) {
		case ROP_COPY:
			memset_io(dest, rect->color, (rect->width >> 3));
			break;
		case ROP_XOR:
			fb_writeb(~(fb_readb(dest)), dest);
			break;
		}
	}
}

static void hgafb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
{
	u_int rows, y1, y2;
	u8 __iomem *src;
	u8 __iomem *dest;

	if (area->dy <= area->sy) {
		y1 = area->sy;
		y2 = area->dy;

		for (rows = area->height; rows--; ) {
			src = rowaddr(info, y1) + (area->sx >> 3);
			dest = rowaddr(info, y2) + (area->dx >> 3);
			memmove(dest, src, (area->width >> 3));
			y1++;
			y2++;
		}
	} else {
		y1 = area->sy + area->height - 1;
		y2 = area->dy + area->height - 1;

		for (rows = area->height; rows--;) {
			src = rowaddr(info, y1) + (area->sx >> 3);
			dest = rowaddr(info, y2) + (area->dx >> 3);
			memmove(dest, src, (area->width >> 3));
			y1--;
			y2--;
		}
	}
}

static void hgafb_imageblit(struct fb_info *info, const struct fb_image *image)
{
	u8 __iomem *dest;
	u8 *cdat = (u8 *) image->data;
	u_int rows, y = image->dy;
	u_int x;
	u8 d;

	for (rows = image->height; rows--; y++) {
		for (x = 0; x < image->width; x+= 8) {
			d = *cdat++;
			dest = rowaddr(info, y) + ((image->dx + x)>> 3);
			fb_writeb(d, dest);
		}
	}
}

static struct fb_ops hgafb_ops = {
	.owner		= THIS_MODULE,
	.fb_open	= hgafb_open,
	.fb_release	= hgafb_release,
	.fb_setcolreg	= hgafb_setcolreg,
	.fb_pan_display	= hgafb_pan_display,
	.fb_blank	= hgafb_blank,
	.fb_fillrect	= hgafb_fillrect,
	.fb_copyarea	= hgafb_copyarea,
	.fb_imageblit	= hgafb_imageblit,
};
		
/* ------------------------------------------------------------------------- *
 *
 * Functions in fb_info
 * 
 * ------------------------------------------------------------------------- */

/* ------------------------------------------------------------------------- */
    
	/*
	 *  Initialization
	 */

static int hgafb_probe(struct platform_device *pdev)
{
	struct fb_info *info;

	if (! hga_card_detect()) {
		printk(KERN_INFO "hgafb: HGA card not detected.\n");
		if (hga_vram)
			iounmap(hga_vram);
		return -EINVAL;
	}

	printk(KERN_INFO "hgafb: %s with %ldK of memory detected.\n",
		hga_type_name, hga_vram_len/1024);

	info = framebuffer_alloc(0, &pdev->dev);
	if (!info) {
		iounmap(hga_vram);
		return -ENOMEM;
	}

	hga_fix.smem_start = (unsigned long)hga_vram;
	hga_fix.smem_len = hga_vram_len;

	info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
	info->var = hga_default_var;
	info->fix = hga_fix;
	info->monspecs.hfmin = 0;
	info->monspecs.hfmax = 0;
	info->monspecs.vfmin = 10000;
	info->monspecs.vfmax = 10000;
	info->monspecs.dpms = 0;
	info->fbops = &hgafb_ops;
	info->screen_base = hga_vram;

        if (register_framebuffer(info) < 0) {
		framebuffer_release(info);
		iounmap(hga_vram);
		return -EINVAL;
	}

	fb_info(info, "%s frame buffer device\n", info->fix.id);
	platform_set_drvdata(pdev, info);
	return 0;
}

static int hgafb_remove(struct platform_device *pdev)
{
	struct fb_info *info = platform_get_drvdata(pdev);

	hga_txt_mode();
	hga_clear_screen();

	if (info) {
		unregister_framebuffer(info);
		framebuffer_release(info);
	}

	iounmap(hga_vram);

	if (release_io_ports)
		release_region(0x3b0, 12);

	if (release_io_port)
		release_region(0x3bf, 1);

	return 0;
}

static struct platform_driver hgafb_driver = {
	.probe = hgafb_probe,
	.remove = hgafb_remove,
	.driver = {
		.name = "hgafb",
	},
};

static struct platform_device *hgafb_device;

static int __init hgafb_init(void)
{
	int ret;

	if (fb_get_options("hgafb", NULL))
		return -ENODEV;

	ret = platform_driver_register(&hgafb_driver);

	if (!ret) {
		hgafb_device = platform_device_register_simple("hgafb", 0, NULL, 0);

		if (IS_ERR(hgafb_device)) {
			platform_driver_unregister(&hgafb_driver);
			ret = PTR_ERR(hgafb_device);
		}
	}

	return ret;
}

static void __exit hgafb_exit(void)
{
	platform_device_unregister(hgafb_device);
	platform_driver_unregister(&hgafb_driver);
}

/* -------------------------------------------------------------------------
 *
 *  Modularization
 *
 * ------------------------------------------------------------------------- */

MODULE_AUTHOR("Ferenc Bakonyi (fero@drama.obuda.kando.hu)");
MODULE_DESCRIPTION("FBDev driver for Hercules Graphics Adaptor");
MODULE_LICENSE("GPL");

module_param(nologo, bool, 0);
MODULE_PARM_DESC(nologo, "Disables startup logo if != 0 (default=0)");
module_init(hgafb_init);
module_exit(hgafb_exit);