xref: /openbmc/linux/drivers/video/fbdev/hgafb.c (revision e3b9f1e8)
1 /*
2  * linux/drivers/video/hgafb.c -- Hercules graphics adaptor frame buffer device
3  *
4  *      Created 25 Nov 1999 by Ferenc Bakonyi (fero@drama.obuda.kando.hu)
5  *      Based on skeletonfb.c by Geert Uytterhoeven and
6  *               mdacon.c by Andrew Apted
7  *
8  * History:
9  *
10  * - Revision 0.1.8 (23 Oct 2002): Ported to new framebuffer api.
11  *
12  * - Revision 0.1.7 (23 Jan 2001): fix crash resulting from MDA only cards
13  *				   being detected as Hercules.	 (Paul G.)
14  * - Revision 0.1.6 (17 Aug 2000): new style structs
15  *                                 documentation
16  * - Revision 0.1.5 (13 Mar 2000): spinlocks instead of saveflags();cli();etc
17  *                                 minor fixes
18  * - Revision 0.1.4 (24 Jan 2000): fixed a bug in hga_card_detect() for
19  *                                  HGA-only systems
20  * - Revision 0.1.3 (22 Jan 2000): modified for the new fb_info structure
21  *                                 screen is cleared after rmmod
22  *                                 virtual resolutions
23  *                                 module parameter 'nologo={0|1}'
24  *                                 the most important: boot logo :)
25  * - Revision 0.1.0  (6 Dec 1999): faster scrolling and minor fixes
26  * - First release  (25 Nov 1999)
27  *
28  * This file is subject to the terms and conditions of the GNU General Public
29  * License.  See the file COPYING in the main directory of this archive
30  * for more details.
31  */
32 
33 #include <linux/module.h>
34 #include <linux/kernel.h>
35 #include <linux/errno.h>
36 #include <linux/spinlock.h>
37 #include <linux/string.h>
38 #include <linux/mm.h>
39 #include <linux/delay.h>
40 #include <linux/fb.h>
41 #include <linux/init.h>
42 #include <linux/ioport.h>
43 #include <linux/platform_device.h>
44 #include <asm/io.h>
45 #include <asm/vga.h>
46 
47 #if 0
48 #define DPRINTK(args...) printk(KERN_DEBUG __FILE__": " ##args)
49 #else
50 #define DPRINTK(args...)
51 #endif
52 
53 #if 0
54 #define CHKINFO(ret) if (info != &fb_info) { printk(KERN_DEBUG __FILE__": This should never happen, line:%d \n", __LINE__); return ret; }
55 #else
56 #define CHKINFO(ret)
57 #endif
58 
59 /* Description of the hardware layout */
60 
61 static void __iomem *hga_vram;			/* Base of video memory */
62 static unsigned long hga_vram_len;		/* Size of video memory */
63 
64 #define HGA_ROWADDR(row) ((row%4)*8192 + (row>>2)*90)
65 #define HGA_TXT			0
66 #define HGA_GFX			1
67 
68 static inline u8 __iomem * rowaddr(struct fb_info *info, u_int row)
69 {
70 	return info->screen_base + HGA_ROWADDR(row);
71 }
72 
73 static int hga_mode = -1;			/* 0 = txt, 1 = gfx mode */
74 
75 static enum { TYPE_HERC, TYPE_HERCPLUS, TYPE_HERCCOLOR } hga_type;
76 static char *hga_type_name;
77 
78 #define HGA_INDEX_PORT		0x3b4		/* Register select port */
79 #define HGA_VALUE_PORT		0x3b5		/* Register value port */
80 #define HGA_MODE_PORT		0x3b8		/* Mode control port */
81 #define HGA_STATUS_PORT		0x3ba		/* Status and Config port */
82 #define HGA_GFX_PORT		0x3bf		/* Graphics control port */
83 
84 /* HGA register values */
85 
86 #define HGA_CURSOR_BLINKING	0x00
87 #define HGA_CURSOR_OFF		0x20
88 #define HGA_CURSOR_SLOWBLINK	0x60
89 
90 #define HGA_MODE_GRAPHICS	0x02
91 #define HGA_MODE_VIDEO_EN	0x08
92 #define HGA_MODE_BLINK_EN	0x20
93 #define HGA_MODE_GFX_PAGE1	0x80
94 
95 #define HGA_STATUS_HSYNC	0x01
96 #define HGA_STATUS_VSYNC	0x80
97 #define HGA_STATUS_VIDEO	0x08
98 
99 #define HGA_CONFIG_COL132	0x08
100 #define HGA_GFX_MODE_EN		0x01
101 #define HGA_GFX_PAGE_EN		0x02
102 
103 /* Global locks */
104 
105 static DEFINE_SPINLOCK(hga_reg_lock);
106 
107 /* Framebuffer driver structures */
108 
109 static const struct fb_var_screeninfo hga_default_var = {
110 	.xres		= 720,
111 	.yres 		= 348,
112 	.xres_virtual 	= 720,
113 	.yres_virtual	= 348,
114 	.bits_per_pixel = 1,
115 	.red 		= {0, 1, 0},
116 	.green 		= {0, 1, 0},
117 	.blue 		= {0, 1, 0},
118 	.transp 	= {0, 0, 0},
119 	.height 	= -1,
120 	.width 		= -1,
121 };
122 
123 static struct fb_fix_screeninfo hga_fix = {
124 	.id 		= "HGA",
125 	.type 		= FB_TYPE_PACKED_PIXELS,	/* (not sure) */
126 	.visual 	= FB_VISUAL_MONO10,
127 	.xpanstep 	= 8,
128 	.ypanstep 	= 8,
129 	.line_length 	= 90,
130 	.accel 		= FB_ACCEL_NONE
131 };
132 
133 /* Don't assume that tty1 will be the initial current console. */
134 static int release_io_port = 0;
135 static int release_io_ports = 0;
136 static bool nologo = 0;
137 
138 /* -------------------------------------------------------------------------
139  *
140  * Low level hardware functions
141  *
142  * ------------------------------------------------------------------------- */
143 
144 static void write_hga_b(unsigned int val, unsigned char reg)
145 {
146 	outb_p(reg, HGA_INDEX_PORT);
147 	outb_p(val, HGA_VALUE_PORT);
148 }
149 
150 static void write_hga_w(unsigned int val, unsigned char reg)
151 {
152 	outb_p(reg,   HGA_INDEX_PORT); outb_p(val >> 8,   HGA_VALUE_PORT);
153 	outb_p(reg+1, HGA_INDEX_PORT); outb_p(val & 0xff, HGA_VALUE_PORT);
154 }
155 
156 static int test_hga_b(unsigned char val, unsigned char reg)
157 {
158 	outb_p(reg, HGA_INDEX_PORT);
159 	outb  (val, HGA_VALUE_PORT);
160 	udelay(20); val = (inb_p(HGA_VALUE_PORT) == val);
161 	return val;
162 }
163 
164 static void hga_clear_screen(void)
165 {
166 	unsigned char fillchar = 0xbf; /* magic */
167 	unsigned long flags;
168 
169 	spin_lock_irqsave(&hga_reg_lock, flags);
170 	if (hga_mode == HGA_TXT)
171 		fillchar = ' ';
172 	else if (hga_mode == HGA_GFX)
173 		fillchar = 0x00;
174 	spin_unlock_irqrestore(&hga_reg_lock, flags);
175 	if (fillchar != 0xbf)
176 		memset_io(hga_vram, fillchar, hga_vram_len);
177 }
178 
179 static void hga_txt_mode(void)
180 {
181 	unsigned long flags;
182 
183 	spin_lock_irqsave(&hga_reg_lock, flags);
184 	outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_BLINK_EN, HGA_MODE_PORT);
185 	outb_p(0x00, HGA_GFX_PORT);
186 	outb_p(0x00, HGA_STATUS_PORT);
187 
188 	write_hga_b(0x61, 0x00);	/* horizontal total */
189 	write_hga_b(0x50, 0x01);	/* horizontal displayed */
190 	write_hga_b(0x52, 0x02);	/* horizontal sync pos */
191 	write_hga_b(0x0f, 0x03);	/* horizontal sync width */
192 
193 	write_hga_b(0x19, 0x04);	/* vertical total */
194 	write_hga_b(0x06, 0x05);	/* vertical total adjust */
195 	write_hga_b(0x19, 0x06);	/* vertical displayed */
196 	write_hga_b(0x19, 0x07);	/* vertical sync pos */
197 
198 	write_hga_b(0x02, 0x08);	/* interlace mode */
199 	write_hga_b(0x0d, 0x09);	/* maximum scanline */
200 	write_hga_b(0x0c, 0x0a);	/* cursor start */
201 	write_hga_b(0x0d, 0x0b);	/* cursor end */
202 
203 	write_hga_w(0x0000, 0x0c);	/* start address */
204 	write_hga_w(0x0000, 0x0e);	/* cursor location */
205 
206 	hga_mode = HGA_TXT;
207 	spin_unlock_irqrestore(&hga_reg_lock, flags);
208 }
209 
210 static void hga_gfx_mode(void)
211 {
212 	unsigned long flags;
213 
214 	spin_lock_irqsave(&hga_reg_lock, flags);
215 	outb_p(0x00, HGA_STATUS_PORT);
216 	outb_p(HGA_GFX_MODE_EN, HGA_GFX_PORT);
217 	outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_GRAPHICS, HGA_MODE_PORT);
218 
219 	write_hga_b(0x35, 0x00);	/* horizontal total */
220 	write_hga_b(0x2d, 0x01);	/* horizontal displayed */
221 	write_hga_b(0x2e, 0x02);	/* horizontal sync pos */
222 	write_hga_b(0x07, 0x03);	/* horizontal sync width */
223 
224 	write_hga_b(0x5b, 0x04);	/* vertical total */
225 	write_hga_b(0x02, 0x05);	/* vertical total adjust */
226 	write_hga_b(0x57, 0x06);	/* vertical displayed */
227 	write_hga_b(0x57, 0x07);	/* vertical sync pos */
228 
229 	write_hga_b(0x02, 0x08);	/* interlace mode */
230 	write_hga_b(0x03, 0x09);	/* maximum scanline */
231 	write_hga_b(0x00, 0x0a);	/* cursor start */
232 	write_hga_b(0x00, 0x0b);	/* cursor end */
233 
234 	write_hga_w(0x0000, 0x0c);	/* start address */
235 	write_hga_w(0x0000, 0x0e);	/* cursor location */
236 
237 	hga_mode = HGA_GFX;
238 	spin_unlock_irqrestore(&hga_reg_lock, flags);
239 }
240 
241 static void hga_show_logo(struct fb_info *info)
242 {
243 /*
244 	void __iomem *dest = hga_vram;
245 	char *logo = linux_logo_bw;
246 	int x, y;
247 
248 	for (y = 134; y < 134 + 80 ; y++) * this needs some cleanup *
249 		for (x = 0; x < 10 ; x++)
250 			writeb(~*(logo++),(dest + HGA_ROWADDR(y) + x + 40));
251 */
252 }
253 
254 static void hga_pan(unsigned int xoffset, unsigned int yoffset)
255 {
256 	unsigned int base;
257 	unsigned long flags;
258 
259 	base = (yoffset / 8) * 90 + xoffset;
260 	spin_lock_irqsave(&hga_reg_lock, flags);
261 	write_hga_w(base, 0x0c);	/* start address */
262 	spin_unlock_irqrestore(&hga_reg_lock, flags);
263 	DPRINTK("hga_pan: base:%d\n", base);
264 }
265 
266 static void hga_blank(int blank_mode)
267 {
268 	unsigned long flags;
269 
270 	spin_lock_irqsave(&hga_reg_lock, flags);
271 	if (blank_mode) {
272 		outb_p(0x00, HGA_MODE_PORT);	/* disable video */
273 	} else {
274 		outb_p(HGA_MODE_VIDEO_EN | HGA_MODE_GRAPHICS, HGA_MODE_PORT);
275 	}
276 	spin_unlock_irqrestore(&hga_reg_lock, flags);
277 }
278 
279 static int hga_card_detect(void)
280 {
281 	int count = 0;
282 	void __iomem *p, *q;
283 	unsigned short p_save, q_save;
284 
285 	hga_vram_len  = 0x08000;
286 
287 	hga_vram = ioremap(0xb0000, hga_vram_len);
288 
289 	if (request_region(0x3b0, 12, "hgafb"))
290 		release_io_ports = 1;
291 	if (request_region(0x3bf, 1, "hgafb"))
292 		release_io_port = 1;
293 
294 	/* do a memory check */
295 
296 	p = hga_vram;
297 	q = hga_vram + 0x01000;
298 
299 	p_save = readw(p); q_save = readw(q);
300 
301 	writew(0xaa55, p); if (readw(p) == 0xaa55) count++;
302 	writew(0x55aa, p); if (readw(p) == 0x55aa) count++;
303 	writew(p_save, p);
304 
305 	if (count != 2)
306 		goto error;
307 
308 	/* Ok, there is definitely a card registering at the correct
309 	 * memory location, so now we do an I/O port test.
310 	 */
311 
312 	if (!test_hga_b(0x66, 0x0f))	    /* cursor low register */
313 		goto error;
314 
315 	if (!test_hga_b(0x99, 0x0f))     /* cursor low register */
316 		goto error;
317 
318 	/* See if the card is a Hercules, by checking whether the vsync
319 	 * bit of the status register is changing.  This test lasts for
320 	 * approximately 1/10th of a second.
321 	 */
322 
323 	p_save = q_save = inb_p(HGA_STATUS_PORT) & HGA_STATUS_VSYNC;
324 
325 	for (count=0; count < 50000 && p_save == q_save; count++) {
326 		q_save = inb(HGA_STATUS_PORT) & HGA_STATUS_VSYNC;
327 		udelay(2);
328 	}
329 
330 	if (p_save == q_save)
331 		goto error;
332 
333 	switch (inb_p(HGA_STATUS_PORT) & 0x70) {
334 		case 0x10:
335 			hga_type = TYPE_HERCPLUS;
336 			hga_type_name = "HerculesPlus";
337 			break;
338 		case 0x50:
339 			hga_type = TYPE_HERCCOLOR;
340 			hga_type_name = "HerculesColor";
341 			break;
342 		default:
343 			hga_type = TYPE_HERC;
344 			hga_type_name = "Hercules";
345 			break;
346 	}
347 	return 1;
348 error:
349 	if (release_io_ports)
350 		release_region(0x3b0, 12);
351 	if (release_io_port)
352 		release_region(0x3bf, 1);
353 	return 0;
354 }
355 
356 /**
357  *	hgafb_open - open the framebuffer device
358  *	@info:pointer to fb_info object containing info for current hga board
359  *	@int:open by console system or userland.
360  */
361 
362 static int hgafb_open(struct fb_info *info, int init)
363 {
364 	hga_gfx_mode();
365 	hga_clear_screen();
366 	if (!nologo) hga_show_logo(info);
367 	return 0;
368 }
369 
370 /**
371  *	hgafb_open - open the framebuffer device
372  *	@info:pointer to fb_info object containing info for current hga board
373  *	@int:open by console system or userland.
374  */
375 
376 static int hgafb_release(struct fb_info *info, int init)
377 {
378 	hga_txt_mode();
379 	hga_clear_screen();
380 	return 0;
381 }
382 
383 /**
384  *	hgafb_setcolreg - set color registers
385  *	@regno:register index to set
386  *	@red:red value, unused
387  *	@green:green value, unused
388  *	@blue:blue value, unused
389  *	@transp:transparency value, unused
390  *	@info:unused
391  *
392  *	This callback function is used to set the color registers of a HGA
393  *	board. Since we have only two fixed colors only @regno is checked.
394  *	A zero is returned on success and 1 for failure.
395  */
396 
397 static int hgafb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
398 			   u_int transp, struct fb_info *info)
399 {
400 	if (regno > 1)
401 		return 1;
402 	return 0;
403 }
404 
405 /**
406  *	hga_pan_display - pan or wrap the display
407  *	@var:contains new xoffset, yoffset and vmode values
408  *	@info:pointer to fb_info object containing info for current hga board
409  *
410  *	This function looks only at xoffset, yoffset and the %FB_VMODE_YWRAP
411  *	flag in @var. If input parameters are correct it calls hga_pan() to
412  *	program the hardware. @info->var is updated to the new values.
413  *	A zero is returned on success and %-EINVAL for failure.
414  */
415 
416 static int hgafb_pan_display(struct fb_var_screeninfo *var,
417 			     struct fb_info *info)
418 {
419 	if (var->vmode & FB_VMODE_YWRAP) {
420 		if (var->yoffset >= info->var.yres_virtual ||
421 		    var->xoffset)
422 			return -EINVAL;
423 	} else {
424 		if (var->xoffset + info->var.xres > info->var.xres_virtual
425 		 || var->yoffset + info->var.yres > info->var.yres_virtual
426 		 || var->yoffset % 8)
427 			return -EINVAL;
428 	}
429 
430 	hga_pan(var->xoffset, var->yoffset);
431 	return 0;
432 }
433 
434 /**
435  *	hgafb_blank - (un)blank the screen
436  *	@blank_mode:blanking method to use
437  *	@info:unused
438  *
439  *	Blank the screen if blank_mode != 0, else unblank.
440  *	Implements VESA suspend and powerdown modes on hardware that supports
441  *	disabling hsync/vsync:
442  *		@blank_mode == 2 means suspend vsync,
443  *		@blank_mode == 3 means suspend hsync,
444  *		@blank_mode == 4 means powerdown.
445  */
446 
447 static int hgafb_blank(int blank_mode, struct fb_info *info)
448 {
449 	hga_blank(blank_mode);
450 	return 0;
451 }
452 
453 /*
454  * Accel functions
455  */
456 static void hgafb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
457 {
458 	u_int rows, y;
459 	u8 __iomem *dest;
460 
461 	y = rect->dy;
462 
463 	for (rows = rect->height; rows--; y++) {
464 		dest = rowaddr(info, y) + (rect->dx >> 3);
465 		switch (rect->rop) {
466 		case ROP_COPY:
467 			memset_io(dest, rect->color, (rect->width >> 3));
468 			break;
469 		case ROP_XOR:
470 			fb_writeb(~(fb_readb(dest)), dest);
471 			break;
472 		}
473 	}
474 }
475 
476 static void hgafb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
477 {
478 	u_int rows, y1, y2;
479 	u8 __iomem *src;
480 	u8 __iomem *dest;
481 
482 	if (area->dy <= area->sy) {
483 		y1 = area->sy;
484 		y2 = area->dy;
485 
486 		for (rows = area->height; rows--; ) {
487 			src = rowaddr(info, y1) + (area->sx >> 3);
488 			dest = rowaddr(info, y2) + (area->dx >> 3);
489 			memmove(dest, src, (area->width >> 3));
490 			y1++;
491 			y2++;
492 		}
493 	} else {
494 		y1 = area->sy + area->height - 1;
495 		y2 = area->dy + area->height - 1;
496 
497 		for (rows = area->height; rows--;) {
498 			src = rowaddr(info, y1) + (area->sx >> 3);
499 			dest = rowaddr(info, y2) + (area->dx >> 3);
500 			memmove(dest, src, (area->width >> 3));
501 			y1--;
502 			y2--;
503 		}
504 	}
505 }
506 
507 static void hgafb_imageblit(struct fb_info *info, const struct fb_image *image)
508 {
509 	u8 __iomem *dest;
510 	u8 *cdat = (u8 *) image->data;
511 	u_int rows, y = image->dy;
512 	u_int x;
513 	u8 d;
514 
515 	for (rows = image->height; rows--; y++) {
516 		for (x = 0; x < image->width; x+= 8) {
517 			d = *cdat++;
518 			dest = rowaddr(info, y) + ((image->dx + x)>> 3);
519 			fb_writeb(d, dest);
520 		}
521 	}
522 }
523 
524 static struct fb_ops hgafb_ops = {
525 	.owner		= THIS_MODULE,
526 	.fb_open	= hgafb_open,
527 	.fb_release	= hgafb_release,
528 	.fb_setcolreg	= hgafb_setcolreg,
529 	.fb_pan_display	= hgafb_pan_display,
530 	.fb_blank	= hgafb_blank,
531 	.fb_fillrect	= hgafb_fillrect,
532 	.fb_copyarea	= hgafb_copyarea,
533 	.fb_imageblit	= hgafb_imageblit,
534 };
535 
536 /* ------------------------------------------------------------------------- *
537  *
538  * Functions in fb_info
539  *
540  * ------------------------------------------------------------------------- */
541 
542 /* ------------------------------------------------------------------------- */
543 
544 	/*
545 	 *  Initialization
546 	 */
547 
548 static int hgafb_probe(struct platform_device *pdev)
549 {
550 	struct fb_info *info;
551 
552 	if (! hga_card_detect()) {
553 		printk(KERN_INFO "hgafb: HGA card not detected.\n");
554 		if (hga_vram)
555 			iounmap(hga_vram);
556 		return -EINVAL;
557 	}
558 
559 	printk(KERN_INFO "hgafb: %s with %ldK of memory detected.\n",
560 		hga_type_name, hga_vram_len/1024);
561 
562 	info = framebuffer_alloc(0, &pdev->dev);
563 	if (!info) {
564 		iounmap(hga_vram);
565 		return -ENOMEM;
566 	}
567 
568 	hga_fix.smem_start = (unsigned long)hga_vram;
569 	hga_fix.smem_len = hga_vram_len;
570 
571 	info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
572 	info->var = hga_default_var;
573 	info->fix = hga_fix;
574 	info->monspecs.hfmin = 0;
575 	info->monspecs.hfmax = 0;
576 	info->monspecs.vfmin = 10000;
577 	info->monspecs.vfmax = 10000;
578 	info->monspecs.dpms = 0;
579 	info->fbops = &hgafb_ops;
580 	info->screen_base = hga_vram;
581 
582         if (register_framebuffer(info) < 0) {
583 		framebuffer_release(info);
584 		iounmap(hga_vram);
585 		return -EINVAL;
586 	}
587 
588 	fb_info(info, "%s frame buffer device\n", info->fix.id);
589 	platform_set_drvdata(pdev, info);
590 	return 0;
591 }
592 
593 static int hgafb_remove(struct platform_device *pdev)
594 {
595 	struct fb_info *info = platform_get_drvdata(pdev);
596 
597 	hga_txt_mode();
598 	hga_clear_screen();
599 
600 	if (info) {
601 		unregister_framebuffer(info);
602 		framebuffer_release(info);
603 	}
604 
605 	iounmap(hga_vram);
606 
607 	if (release_io_ports)
608 		release_region(0x3b0, 12);
609 
610 	if (release_io_port)
611 		release_region(0x3bf, 1);
612 
613 	return 0;
614 }
615 
616 static struct platform_driver hgafb_driver = {
617 	.probe = hgafb_probe,
618 	.remove = hgafb_remove,
619 	.driver = {
620 		.name = "hgafb",
621 	},
622 };
623 
624 static struct platform_device *hgafb_device;
625 
626 static int __init hgafb_init(void)
627 {
628 	int ret;
629 
630 	if (fb_get_options("hgafb", NULL))
631 		return -ENODEV;
632 
633 	ret = platform_driver_register(&hgafb_driver);
634 
635 	if (!ret) {
636 		hgafb_device = platform_device_register_simple("hgafb", 0, NULL, 0);
637 
638 		if (IS_ERR(hgafb_device)) {
639 			platform_driver_unregister(&hgafb_driver);
640 			ret = PTR_ERR(hgafb_device);
641 		}
642 	}
643 
644 	return ret;
645 }
646 
647 static void __exit hgafb_exit(void)
648 {
649 	platform_device_unregister(hgafb_device);
650 	platform_driver_unregister(&hgafb_driver);
651 }
652 
653 /* -------------------------------------------------------------------------
654  *
655  *  Modularization
656  *
657  * ------------------------------------------------------------------------- */
658 
659 MODULE_AUTHOR("Ferenc Bakonyi (fero@drama.obuda.kando.hu)");
660 MODULE_DESCRIPTION("FBDev driver for Hercules Graphics Adaptor");
661 MODULE_LICENSE("GPL");
662 
663 module_param(nologo, bool, 0);
664 MODULE_PARM_DESC(nologo, "Disables startup logo if != 0 (default=0)");
665 module_init(hgafb_init);
666 module_exit(hgafb_exit);
667