xref: /openbmc/linux/drivers/video/fbdev/acornfb.c (revision 6d99a79c)
1 /*
2  *  linux/drivers/video/acornfb.c
3  *
4  *  Copyright (C) 1998-2001 Russell King
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * Frame buffer code for Acorn platforms
11  *
12  * NOTE: Most of the modes with X!=640 will disappear shortly.
13  * NOTE: Startup setting of HS & VS polarity not supported.
14  *       (do we need to support it if we're coming up in 640x480?)
15  *
16  * FIXME: (things broken by the "new improved" FBCON API)
17  *  - Blanking 8bpp displays with VIDC
18  */
19 
20 #include <linux/module.h>
21 #include <linux/kernel.h>
22 #include <linux/errno.h>
23 #include <linux/string.h>
24 #include <linux/ctype.h>
25 #include <linux/mm.h>
26 #include <linux/init.h>
27 #include <linux/fb.h>
28 #include <linux/platform_device.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/io.h>
31 #include <linux/gfp.h>
32 
33 #include <mach/hardware.h>
34 #include <asm/irq.h>
35 #include <asm/mach-types.h>
36 #include <asm/pgtable.h>
37 
38 #include "acornfb.h"
39 
40 /*
41  * Default resolution.
42  * NOTE that it has to be supported in the table towards
43  * the end of this file.
44  */
45 #define DEFAULT_XRES	640
46 #define DEFAULT_YRES	480
47 #define DEFAULT_BPP	4
48 
49 /*
50  * define this to debug the video mode selection
51  */
52 #undef DEBUG_MODE_SELECTION
53 
54 /*
55  * Translation from RISC OS monitor types to actual
56  * HSYNC and VSYNC frequency ranges.  These are
57  * probably not right, but they're the best info I
58  * have.  Allow 1% either way on the nominal for TVs.
59  */
60 #define NR_MONTYPES	6
61 static struct fb_monspecs monspecs[NR_MONTYPES] = {
62 	{	/* TV		*/
63 		.hfmin	= 15469,
64 		.hfmax	= 15781,
65 		.vfmin	= 49,
66 		.vfmax	= 51,
67 	}, {	/* Multi Freq	*/
68 		.hfmin	= 0,
69 		.hfmax	= 99999,
70 		.vfmin	= 0,
71 		.vfmax	= 199,
72 	}, {	/* Hi-res mono	*/
73 		.hfmin	= 58608,
74 		.hfmax	= 58608,
75 		.vfmin	= 64,
76 		.vfmax	= 64,
77 	}, {	/* VGA		*/
78 		.hfmin	= 30000,
79 		.hfmax	= 70000,
80 		.vfmin	= 60,
81 		.vfmax	= 60,
82 	}, {	/* SVGA		*/
83 		.hfmin	= 30000,
84 		.hfmax	= 70000,
85 		.vfmin	= 56,
86 		.vfmax	= 75,
87 	}, {
88 		.hfmin	= 30000,
89 		.hfmax	= 70000,
90 		.vfmin	= 60,
91 		.vfmax	= 60,
92 	}
93 };
94 
95 static struct fb_info fb_info;
96 static struct acornfb_par current_par;
97 static struct vidc_timing current_vidc;
98 
99 extern unsigned int vram_size;	/* set by setup.c */
100 
101 #ifdef HAS_VIDC20
102 #include <mach/acornfb.h>
103 
104 #define MAX_SIZE	(2*1024*1024)
105 
106 /* VIDC20 has a different set of rules from the VIDC:
107  *  hcr  : must be multiple of 4
108  *  hswr : must be even
109  *  hdsr : must be even
110  *  hder : must be even
111  *  vcr  : >= 2, (interlace, must be odd)
112  *  vswr : >= 1
113  *  vdsr : >= 1
114  *  vder : >= vdsr
115  */
116 static void acornfb_set_timing(struct fb_info *info)
117 {
118 	struct fb_var_screeninfo *var = &info->var;
119 	struct vidc_timing vidc;
120 	u_int vcr, fsize;
121 	u_int ext_ctl, dat_ctl;
122 	u_int words_per_line;
123 
124 	memset(&vidc, 0, sizeof(vidc));
125 
126 	vidc.h_sync_width	= var->hsync_len - 8;
127 	vidc.h_border_start	= vidc.h_sync_width + var->left_margin + 8 - 12;
128 	vidc.h_display_start	= vidc.h_border_start + 12 - 18;
129 	vidc.h_display_end	= vidc.h_display_start + var->xres;
130 	vidc.h_border_end	= vidc.h_display_end + 18 - 12;
131 	vidc.h_cycle		= vidc.h_border_end + var->right_margin + 12 - 8;
132 	vidc.h_interlace	= vidc.h_cycle / 2;
133 	vidc.v_sync_width	= var->vsync_len - 1;
134 	vidc.v_border_start	= vidc.v_sync_width + var->upper_margin;
135 	vidc.v_display_start	= vidc.v_border_start;
136 	vidc.v_display_end	= vidc.v_display_start + var->yres;
137 	vidc.v_border_end	= vidc.v_display_end;
138 	vidc.control		= acornfb_default_control();
139 
140 	vcr = var->vsync_len + var->upper_margin + var->yres +
141 	      var->lower_margin;
142 
143 	if ((var->vmode & FB_VMODE_MASK) == FB_VMODE_INTERLACED) {
144 		vidc.v_cycle = (vcr - 3) / 2;
145 		vidc.control |= VIDC20_CTRL_INT;
146 	} else
147 		vidc.v_cycle = vcr - 2;
148 
149 	switch (var->bits_per_pixel) {
150 	case  1: vidc.control |= VIDC20_CTRL_1BPP;	break;
151 	case  2: vidc.control |= VIDC20_CTRL_2BPP;	break;
152 	case  4: vidc.control |= VIDC20_CTRL_4BPP;	break;
153 	default:
154 	case  8: vidc.control |= VIDC20_CTRL_8BPP;	break;
155 	case 16: vidc.control |= VIDC20_CTRL_16BPP;	break;
156 	case 32: vidc.control |= VIDC20_CTRL_32BPP;	break;
157 	}
158 
159 	acornfb_vidc20_find_rates(&vidc, var);
160 	fsize = var->vsync_len + var->upper_margin + var->lower_margin - 1;
161 
162 	if (memcmp(&current_vidc, &vidc, sizeof(vidc))) {
163 		current_vidc = vidc;
164 
165 		vidc_writel(VIDC20_CTRL | vidc.control);
166 		vidc_writel(0xd0000000 | vidc.pll_ctl);
167 		vidc_writel(0x80000000 | vidc.h_cycle);
168 		vidc_writel(0x81000000 | vidc.h_sync_width);
169 		vidc_writel(0x82000000 | vidc.h_border_start);
170 		vidc_writel(0x83000000 | vidc.h_display_start);
171 		vidc_writel(0x84000000 | vidc.h_display_end);
172 		vidc_writel(0x85000000 | vidc.h_border_end);
173 		vidc_writel(0x86000000);
174 		vidc_writel(0x87000000 | vidc.h_interlace);
175 		vidc_writel(0x90000000 | vidc.v_cycle);
176 		vidc_writel(0x91000000 | vidc.v_sync_width);
177 		vidc_writel(0x92000000 | vidc.v_border_start);
178 		vidc_writel(0x93000000 | vidc.v_display_start);
179 		vidc_writel(0x94000000 | vidc.v_display_end);
180 		vidc_writel(0x95000000 | vidc.v_border_end);
181 		vidc_writel(0x96000000);
182 		vidc_writel(0x97000000);
183 	}
184 
185 	iomd_writel(fsize, IOMD_FSIZE);
186 
187 	ext_ctl = acornfb_default_econtrol();
188 
189 	if (var->sync & FB_SYNC_COMP_HIGH_ACT) /* should be FB_SYNC_COMP */
190 		ext_ctl |= VIDC20_ECTL_HS_NCSYNC | VIDC20_ECTL_VS_NCSYNC;
191 	else {
192 		if (var->sync & FB_SYNC_HOR_HIGH_ACT)
193 			ext_ctl |= VIDC20_ECTL_HS_HSYNC;
194 		else
195 			ext_ctl |= VIDC20_ECTL_HS_NHSYNC;
196 
197 		if (var->sync & FB_SYNC_VERT_HIGH_ACT)
198 			ext_ctl |= VIDC20_ECTL_VS_VSYNC;
199 		else
200 			ext_ctl |= VIDC20_ECTL_VS_NVSYNC;
201 	}
202 
203 	vidc_writel(VIDC20_ECTL | ext_ctl);
204 
205 	words_per_line = var->xres * var->bits_per_pixel / 32;
206 
207 	if (current_par.using_vram && info->fix.smem_len == 2048*1024)
208 		words_per_line /= 2;
209 
210 	/* RiscPC doesn't use the VIDC's VRAM control. */
211 	dat_ctl = VIDC20_DCTL_VRAM_DIS | VIDC20_DCTL_SNA | words_per_line;
212 
213 	/* The data bus width is dependent on both the type
214 	 * and amount of video memory.
215 	 *     DRAM	32bit low
216 	 * 1MB VRAM	32bit
217 	 * 2MB VRAM	64bit
218 	 */
219 	if (current_par.using_vram && current_par.vram_half_sam == 2048)
220 		dat_ctl |= VIDC20_DCTL_BUS_D63_0;
221 	else
222 		dat_ctl |= VIDC20_DCTL_BUS_D31_0;
223 
224 	vidc_writel(VIDC20_DCTL | dat_ctl);
225 
226 #ifdef DEBUG_MODE_SELECTION
227 	printk(KERN_DEBUG "VIDC registers for %dx%dx%d:\n", var->xres,
228 	       var->yres, var->bits_per_pixel);
229 	printk(KERN_DEBUG " H-cycle          : %d\n", vidc.h_cycle);
230 	printk(KERN_DEBUG " H-sync-width     : %d\n", vidc.h_sync_width);
231 	printk(KERN_DEBUG " H-border-start   : %d\n", vidc.h_border_start);
232 	printk(KERN_DEBUG " H-display-start  : %d\n", vidc.h_display_start);
233 	printk(KERN_DEBUG " H-display-end    : %d\n", vidc.h_display_end);
234 	printk(KERN_DEBUG " H-border-end     : %d\n", vidc.h_border_end);
235 	printk(KERN_DEBUG " H-interlace      : %d\n", vidc.h_interlace);
236 	printk(KERN_DEBUG " V-cycle          : %d\n", vidc.v_cycle);
237 	printk(KERN_DEBUG " V-sync-width     : %d\n", vidc.v_sync_width);
238 	printk(KERN_DEBUG " V-border-start   : %d\n", vidc.v_border_start);
239 	printk(KERN_DEBUG " V-display-start  : %d\n", vidc.v_display_start);
240 	printk(KERN_DEBUG " V-display-end    : %d\n", vidc.v_display_end);
241 	printk(KERN_DEBUG " V-border-end     : %d\n", vidc.v_border_end);
242 	printk(KERN_DEBUG " Ext Ctrl  (C)    : 0x%08X\n", ext_ctl);
243 	printk(KERN_DEBUG " PLL Ctrl  (D)    : 0x%08X\n", vidc.pll_ctl);
244 	printk(KERN_DEBUG " Ctrl      (E)    : 0x%08X\n", vidc.control);
245 	printk(KERN_DEBUG " Data Ctrl (F)    : 0x%08X\n", dat_ctl);
246 	printk(KERN_DEBUG " Fsize            : 0x%08X\n", fsize);
247 #endif
248 }
249 
250 /*
251  * We have to take note of the VIDC20's 16-bit palette here.
252  * The VIDC20 looks up a 16 bit pixel as follows:
253  *
254  *   bits   111111
255  *          5432109876543210
256  *   red            ++++++++  (8 bits,  7 to 0)
257  *  green       ++++++++      (8 bits, 11 to 4)
258  *   blue   ++++++++          (8 bits, 15 to 8)
259  *
260  * We use a pixel which looks like:
261  *
262  *   bits   111111
263  *          5432109876543210
264  *   red               +++++  (5 bits,  4 to  0)
265  *  green         +++++       (5 bits,  9 to  5)
266  *   blue    +++++            (5 bits, 14 to 10)
267  */
268 static int
269 acornfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
270 		  u_int trans, struct fb_info *info)
271 {
272 	union palette pal;
273 
274 	if (regno >= current_par.palette_size)
275 		return 1;
276 
277 	if (regno < 16 && info->fix.visual == FB_VISUAL_DIRECTCOLOR) {
278 		u32 pseudo_val;
279 
280 		pseudo_val  = regno << info->var.red.offset;
281 		pseudo_val |= regno << info->var.green.offset;
282 		pseudo_val |= regno << info->var.blue.offset;
283 
284 		((u32 *)info->pseudo_palette)[regno] = pseudo_val;
285 	}
286 
287 	pal.p = 0;
288 	pal.vidc20.red   = red >> 8;
289 	pal.vidc20.green = green >> 8;
290 	pal.vidc20.blue  = blue >> 8;
291 
292 	current_par.palette[regno] = pal;
293 
294 	if (info->var.bits_per_pixel == 16) {
295 		int i;
296 
297 		pal.p = 0;
298 		vidc_writel(0x10000000);
299 		for (i = 0; i < 256; i += 1) {
300 			pal.vidc20.red   = current_par.palette[i       & 31].vidc20.red;
301 			pal.vidc20.green = current_par.palette[(i >> 1) & 31].vidc20.green;
302 			pal.vidc20.blue  = current_par.palette[(i >> 2) & 31].vidc20.blue;
303 			vidc_writel(pal.p);
304 			/* Palette register pointer auto-increments */
305 		}
306 	} else {
307 		vidc_writel(0x10000000 | regno);
308 		vidc_writel(pal.p);
309 	}
310 
311 	return 0;
312 }
313 #endif
314 
315 /*
316  * Before selecting the timing parameters, adjust
317  * the resolution to fit the rules.
318  */
319 static int
320 acornfb_adjust_timing(struct fb_info *info, struct fb_var_screeninfo *var, u_int fontht)
321 {
322 	u_int font_line_len, sam_size, min_size, size, nr_y;
323 
324 	/* xres must be even */
325 	var->xres = (var->xres + 1) & ~1;
326 
327 	/*
328 	 * We don't allow xres_virtual to differ from xres
329 	 */
330 	var->xres_virtual = var->xres;
331 	var->xoffset = 0;
332 
333 	if (current_par.using_vram)
334 		sam_size = current_par.vram_half_sam * 2;
335 	else
336 		sam_size = 16;
337 
338 	/*
339 	 * Now, find a value for yres_virtual which allows
340 	 * us to do ywrap scrolling.  The value of
341 	 * yres_virtual must be such that the end of the
342 	 * displayable frame buffer must be aligned with
343 	 * the start of a font line.
344 	 */
345 	font_line_len = var->xres * var->bits_per_pixel * fontht / 8;
346 	min_size = var->xres * var->yres * var->bits_per_pixel / 8;
347 
348 	/*
349 	 * If minimum screen size is greater than that we have
350 	 * available, reject it.
351 	 */
352 	if (min_size > info->fix.smem_len)
353 		return -EINVAL;
354 
355 	/* Find int 'y', such that y * fll == s * sam < maxsize
356 	 * y = s * sam / fll; s = maxsize / sam
357 	 */
358 	for (size = info->fix.smem_len;
359 	     nr_y = size / font_line_len, min_size <= size;
360 	     size -= sam_size) {
361 		if (nr_y * font_line_len == size)
362 			break;
363 	}
364 	nr_y *= fontht;
365 
366 	if (var->accel_flags & FB_ACCELF_TEXT) {
367 		if (min_size > size) {
368 			/*
369 			 * failed, use ypan
370 			 */
371 			size = info->fix.smem_len;
372 			var->yres_virtual = size / (font_line_len / fontht);
373 		} else
374 			var->yres_virtual = nr_y;
375 	} else if (var->yres_virtual > nr_y)
376 		var->yres_virtual = nr_y;
377 
378 	current_par.screen_end = info->fix.smem_start + size;
379 
380 	/*
381 	 * Fix yres & yoffset if needed.
382 	 */
383 	if (var->yres > var->yres_virtual)
384 		var->yres = var->yres_virtual;
385 
386 	if (var->vmode & FB_VMODE_YWRAP) {
387 		if (var->yoffset > var->yres_virtual)
388 			var->yoffset = var->yres_virtual;
389 	} else {
390 		if (var->yoffset + var->yres > var->yres_virtual)
391 			var->yoffset = var->yres_virtual - var->yres;
392 	}
393 
394 	/* hsync_len must be even */
395 	var->hsync_len = (var->hsync_len + 1) & ~1;
396 
397 #if defined(HAS_VIDC20)
398 	/* left_margin must be even */
399 	if (var->left_margin & 1) {
400 		var->left_margin += 1;
401 		var->right_margin -= 1;
402 	}
403 
404 	/* right_margin must be even */
405 	if (var->right_margin & 1)
406 		var->right_margin += 1;
407 #endif
408 
409 	if (var->vsync_len < 1)
410 		var->vsync_len = 1;
411 
412 	return 0;
413 }
414 
415 static int
416 acornfb_validate_timing(struct fb_var_screeninfo *var,
417 			struct fb_monspecs *monspecs)
418 {
419 	unsigned long hs, vs;
420 
421 	/*
422 	 * hs(Hz) = 10^12 / (pixclock * xtotal)
423 	 * vs(Hz) = hs(Hz) / ytotal
424 	 *
425 	 * No need to do long long divisions or anything
426 	 * like that if you factor it correctly
427 	 */
428 	hs = 1953125000 / var->pixclock;
429 	hs = hs * 512 /
430 	     (var->xres + var->left_margin + var->right_margin + var->hsync_len);
431 	vs = hs /
432 	     (var->yres + var->upper_margin + var->lower_margin + var->vsync_len);
433 
434 	return (vs >= monspecs->vfmin && vs <= monspecs->vfmax &&
435 		hs >= monspecs->hfmin && hs <= monspecs->hfmax) ? 0 : -EINVAL;
436 }
437 
438 static inline void
439 acornfb_update_dma(struct fb_info *info, struct fb_var_screeninfo *var)
440 {
441 	u_int off = var->yoffset * info->fix.line_length;
442 
443 #if defined(HAS_MEMC)
444 	memc_write(VDMA_INIT, off >> 2);
445 #elif defined(HAS_IOMD)
446 	iomd_writel(info->fix.smem_start + off, IOMD_VIDINIT);
447 #endif
448 }
449 
450 static int
451 acornfb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
452 {
453 	u_int fontht;
454 	int err;
455 
456 	/*
457 	 * FIXME: Find the font height
458 	 */
459 	fontht = 8;
460 
461 	var->red.msb_right = 0;
462 	var->green.msb_right = 0;
463 	var->blue.msb_right = 0;
464 	var->transp.msb_right = 0;
465 
466 	switch (var->bits_per_pixel) {
467 	case 1:	case 2:	case 4:	case 8:
468 		var->red.offset    = 0;
469 		var->red.length    = var->bits_per_pixel;
470 		var->green         = var->red;
471 		var->blue          = var->red;
472 		var->transp.offset = 0;
473 		var->transp.length = 0;
474 		break;
475 
476 #ifdef HAS_VIDC20
477 	case 16:
478 		var->red.offset    = 0;
479 		var->red.length    = 5;
480 		var->green.offset  = 5;
481 		var->green.length  = 5;
482 		var->blue.offset   = 10;
483 		var->blue.length   = 5;
484 		var->transp.offset = 15;
485 		var->transp.length = 1;
486 		break;
487 
488 	case 32:
489 		var->red.offset    = 0;
490 		var->red.length    = 8;
491 		var->green.offset  = 8;
492 		var->green.length  = 8;
493 		var->blue.offset   = 16;
494 		var->blue.length   = 8;
495 		var->transp.offset = 24;
496 		var->transp.length = 4;
497 		break;
498 #endif
499 	default:
500 		return -EINVAL;
501 	}
502 
503 	/*
504 	 * Check to see if the pixel rate is valid.
505 	 */
506 	if (!acornfb_valid_pixrate(var))
507 		return -EINVAL;
508 
509 	/*
510 	 * Validate and adjust the resolution to
511 	 * match the video generator hardware.
512 	 */
513 	err = acornfb_adjust_timing(info, var, fontht);
514 	if (err)
515 		return err;
516 
517 	/*
518 	 * Validate the timing against the
519 	 * monitor hardware.
520 	 */
521 	return acornfb_validate_timing(var, &info->monspecs);
522 }
523 
524 static int acornfb_set_par(struct fb_info *info)
525 {
526 	switch (info->var.bits_per_pixel) {
527 	case 1:
528 		current_par.palette_size = 2;
529 		info->fix.visual = FB_VISUAL_MONO10;
530 		break;
531 	case 2:
532 		current_par.palette_size = 4;
533 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
534 		break;
535 	case 4:
536 		current_par.palette_size = 16;
537 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
538 		break;
539 	case 8:
540 		current_par.palette_size = VIDC_PALETTE_SIZE;
541 		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
542 		break;
543 #ifdef HAS_VIDC20
544 	case 16:
545 		current_par.palette_size = 32;
546 		info->fix.visual = FB_VISUAL_DIRECTCOLOR;
547 		break;
548 	case 32:
549 		current_par.palette_size = VIDC_PALETTE_SIZE;
550 		info->fix.visual = FB_VISUAL_DIRECTCOLOR;
551 		break;
552 #endif
553 	default:
554 		BUG();
555 	}
556 
557 	info->fix.line_length	= (info->var.xres * info->var.bits_per_pixel) / 8;
558 
559 #if defined(HAS_MEMC)
560 	{
561 		unsigned long size = info->fix.smem_len - VDMA_XFERSIZE;
562 
563 		memc_write(VDMA_START, 0);
564 		memc_write(VDMA_END, size >> 2);
565 	}
566 #elif defined(HAS_IOMD)
567 	{
568 		unsigned long start, size;
569 		u_int control;
570 
571 		start = info->fix.smem_start;
572 		size  = current_par.screen_end;
573 
574 		if (current_par.using_vram) {
575 			size -= current_par.vram_half_sam;
576 			control = DMA_CR_E | (current_par.vram_half_sam / 256);
577 		} else {
578 			size -= 16;
579 			control = DMA_CR_E | DMA_CR_D | 16;
580 		}
581 
582 		iomd_writel(start,   IOMD_VIDSTART);
583 		iomd_writel(size,    IOMD_VIDEND);
584 		iomd_writel(control, IOMD_VIDCR);
585 	}
586 #endif
587 
588 	acornfb_update_dma(info, &info->var);
589 	acornfb_set_timing(info);
590 
591 	return 0;
592 }
593 
594 static int
595 acornfb_pan_display(struct fb_var_screeninfo *var, struct fb_info *info)
596 {
597 	u_int y_bottom = var->yoffset;
598 
599 	if (!(var->vmode & FB_VMODE_YWRAP))
600 		y_bottom += info->var.yres;
601 
602 	if (y_bottom > info->var.yres_virtual)
603 		return -EINVAL;
604 
605 	acornfb_update_dma(info, var);
606 
607 	return 0;
608 }
609 
610 static struct fb_ops acornfb_ops = {
611 	.owner		= THIS_MODULE,
612 	.fb_check_var	= acornfb_check_var,
613 	.fb_set_par	= acornfb_set_par,
614 	.fb_setcolreg	= acornfb_setcolreg,
615 	.fb_pan_display	= acornfb_pan_display,
616 	.fb_fillrect	= cfb_fillrect,
617 	.fb_copyarea	= cfb_copyarea,
618 	.fb_imageblit	= cfb_imageblit,
619 };
620 
621 /*
622  * Everything after here is initialisation!!!
623  */
624 static struct fb_videomode modedb[] = {
625 	{	/* 320x256 @ 50Hz */
626 		NULL, 50,  320,  256, 125000,  92,  62,  35, 19,  38, 2,
627 		FB_SYNC_COMP_HIGH_ACT,
628 		FB_VMODE_NONINTERLACED
629 	}, {	/* 640x250 @ 50Hz, 15.6 kHz hsync */
630 		NULL, 50,  640,  250,  62500, 185, 123,  38, 21,  76, 3,
631 		0,
632 		FB_VMODE_NONINTERLACED
633 	}, {	/* 640x256 @ 50Hz, 15.6 kHz hsync */
634 		NULL, 50,  640,  256,  62500, 185, 123,  35, 18,  76, 3,
635 		0,
636 		FB_VMODE_NONINTERLACED
637 	}, {	/* 640x512 @ 50Hz, 26.8 kHz hsync */
638 		NULL, 50,  640,  512,  41667, 113,  87,  18,  1,  56, 3,
639 		0,
640 		FB_VMODE_NONINTERLACED
641 	}, {	/* 640x250 @ 70Hz, 31.5 kHz hsync */
642 		NULL, 70,  640,  250,  39722,  48,  16, 109, 88,  96, 2,
643 		0,
644 		FB_VMODE_NONINTERLACED
645 	}, {	/* 640x256 @ 70Hz, 31.5 kHz hsync */
646 		NULL, 70,  640,  256,  39722,  48,  16, 106, 85,  96, 2,
647 		0,
648 		FB_VMODE_NONINTERLACED
649 	}, {	/* 640x352 @ 70Hz, 31.5 kHz hsync */
650 		NULL, 70,  640,  352,  39722,  48,  16,  58, 37,  96, 2,
651 		0,
652 		FB_VMODE_NONINTERLACED
653 	}, {	/* 640x480 @ 60Hz, 31.5 kHz hsync */
654 		NULL, 60,  640,  480,  39722,  48,  16,  32, 11,  96, 2,
655 		0,
656 		FB_VMODE_NONINTERLACED
657 	}, {	/* 800x600 @ 56Hz, 35.2 kHz hsync */
658 		NULL, 56,  800,  600,  27778, 101,  23,  22,  1, 100, 2,
659 		0,
660 		FB_VMODE_NONINTERLACED
661 	}, {	/* 896x352 @ 60Hz, 21.8 kHz hsync */
662 		NULL, 60,  896,  352,  41667,  59,  27,   9,  0, 118, 3,
663 		0,
664 		FB_VMODE_NONINTERLACED
665 	}, {	/* 1024x 768 @ 60Hz, 48.4 kHz hsync */
666 		NULL, 60, 1024,  768,  15385, 160,  24,  29,  3, 136, 6,
667 		0,
668 		FB_VMODE_NONINTERLACED
669 	}, {	/* 1280x1024 @ 60Hz, 63.8 kHz hsync */
670 		NULL, 60, 1280, 1024,   9090, 186,  96,  38,  1, 160, 3,
671 		0,
672 		FB_VMODE_NONINTERLACED
673 	}
674 };
675 
676 static struct fb_videomode acornfb_default_mode = {
677 	.name =		NULL,
678 	.refresh =	60,
679 	.xres =		640,
680 	.yres =		480,
681 	.pixclock =	39722,
682 	.left_margin =	56,
683 	.right_margin =	16,
684 	.upper_margin =	34,
685 	.lower_margin =	9,
686 	.hsync_len =	88,
687 	.vsync_len =	2,
688 	.sync =		0,
689 	.vmode =	FB_VMODE_NONINTERLACED
690 };
691 
692 static void acornfb_init_fbinfo(void)
693 {
694 	static int first = 1;
695 
696 	if (!first)
697 		return;
698 	first = 0;
699 
700 	fb_info.fbops		= &acornfb_ops;
701 	fb_info.flags		= FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
702 	fb_info.pseudo_palette	= current_par.pseudo_palette;
703 
704 	strcpy(fb_info.fix.id, "Acorn");
705 	fb_info.fix.type	= FB_TYPE_PACKED_PIXELS;
706 	fb_info.fix.type_aux	= 0;
707 	fb_info.fix.xpanstep	= 0;
708 	fb_info.fix.ypanstep	= 1;
709 	fb_info.fix.ywrapstep	= 1;
710 	fb_info.fix.line_length	= 0;
711 	fb_info.fix.accel	= FB_ACCEL_NONE;
712 
713 	/*
714 	 * setup initial parameters
715 	 */
716 	memset(&fb_info.var, 0, sizeof(fb_info.var));
717 
718 #if defined(HAS_VIDC20)
719 	fb_info.var.red.length	   = 8;
720 	fb_info.var.transp.length  = 4;
721 #endif
722 	fb_info.var.green	   = fb_info.var.red;
723 	fb_info.var.blue	   = fb_info.var.red;
724 	fb_info.var.nonstd	   = 0;
725 	fb_info.var.activate	   = FB_ACTIVATE_NOW;
726 	fb_info.var.height	   = -1;
727 	fb_info.var.width	   = -1;
728 	fb_info.var.vmode	   = FB_VMODE_NONINTERLACED;
729 	fb_info.var.accel_flags	   = FB_ACCELF_TEXT;
730 
731 	current_par.dram_size	   = 0;
732 	current_par.montype	   = -1;
733 	current_par.dpms	   = 0;
734 }
735 
736 /*
737  * setup acornfb options:
738  *
739  *  mon:hmin-hmax:vmin-vmax:dpms:width:height
740  *	Set monitor parameters:
741  *		hmin   = horizontal minimum frequency (Hz)
742  *		hmax   = horizontal maximum frequency (Hz)	(optional)
743  *		vmin   = vertical minimum frequency (Hz)
744  *		vmax   = vertical maximum frequency (Hz)	(optional)
745  *		dpms   = DPMS supported?			(optional)
746  *		width  = width of picture in mm.		(optional)
747  *		height = height of picture in mm.		(optional)
748  *
749  * montype:type
750  *	Set RISC-OS style monitor type:
751  *		0 (or tv)	- TV frequency
752  *		1 (or multi)	- Multi frequency
753  *		2 (or hires)	- Hi-res monochrome
754  *		3 (or vga)	- VGA
755  *		4 (or svga)	- SVGA
756  *		auto, or option missing
757  *				- try hardware detect
758  *
759  * dram:size
760  *	Set the amount of DRAM to use for the frame buffer
761  *	(even if you have VRAM).
762  *	size can optionally be followed by 'M' or 'K' for
763  *	MB or KB respectively.
764  */
765 static void acornfb_parse_mon(char *opt)
766 {
767 	char *p = opt;
768 
769 	current_par.montype = -2;
770 
771 	fb_info.monspecs.hfmin = simple_strtoul(p, &p, 0);
772 	if (*p == '-')
773 		fb_info.monspecs.hfmax = simple_strtoul(p + 1, &p, 0);
774 	else
775 		fb_info.monspecs.hfmax = fb_info.monspecs.hfmin;
776 
777 	if (*p != ':')
778 		goto bad;
779 
780 	fb_info.monspecs.vfmin = simple_strtoul(p + 1, &p, 0);
781 	if (*p == '-')
782 		fb_info.monspecs.vfmax = simple_strtoul(p + 1, &p, 0);
783 	else
784 		fb_info.monspecs.vfmax = fb_info.monspecs.vfmin;
785 
786 	if (*p != ':')
787 		goto check_values;
788 
789 	fb_info.monspecs.dpms = simple_strtoul(p + 1, &p, 0);
790 
791 	if (*p != ':')
792 		goto check_values;
793 
794 	fb_info.var.width = simple_strtoul(p + 1, &p, 0);
795 
796 	if (*p != ':')
797 		goto check_values;
798 
799 	fb_info.var.height = simple_strtoul(p + 1, NULL, 0);
800 
801 check_values:
802 	if (fb_info.monspecs.hfmax < fb_info.monspecs.hfmin ||
803 	    fb_info.monspecs.vfmax < fb_info.monspecs.vfmin)
804 		goto bad;
805 	return;
806 
807 bad:
808 	printk(KERN_ERR "Acornfb: bad monitor settings: %s\n", opt);
809 	current_par.montype = -1;
810 }
811 
812 static void acornfb_parse_montype(char *opt)
813 {
814 	current_par.montype = -2;
815 
816 	if (strncmp(opt, "tv", 2) == 0) {
817 		opt += 2;
818 		current_par.montype = 0;
819 	} else if (strncmp(opt, "multi", 5) == 0) {
820 		opt += 5;
821 		current_par.montype = 1;
822 	} else if (strncmp(opt, "hires", 5) == 0) {
823 		opt += 5;
824 		current_par.montype = 2;
825 	} else if (strncmp(opt, "vga", 3) == 0) {
826 		opt += 3;
827 		current_par.montype = 3;
828 	} else if (strncmp(opt, "svga", 4) == 0) {
829 		opt += 4;
830 		current_par.montype = 4;
831 	} else if (strncmp(opt, "auto", 4) == 0) {
832 		opt += 4;
833 		current_par.montype = -1;
834 	} else if (isdigit(*opt))
835 		current_par.montype = simple_strtoul(opt, &opt, 0);
836 
837 	if (current_par.montype == -2 ||
838 	    current_par.montype > NR_MONTYPES) {
839 		printk(KERN_ERR "acornfb: unknown monitor type: %s\n",
840 			opt);
841 		current_par.montype = -1;
842 	} else
843 	if (opt && *opt) {
844 		if (strcmp(opt, ",dpms") == 0)
845 			current_par.dpms = 1;
846 		else
847 			printk(KERN_ERR
848 			       "acornfb: unknown monitor option: %s\n",
849 			       opt);
850 	}
851 }
852 
853 static void acornfb_parse_dram(char *opt)
854 {
855 	unsigned int size;
856 
857 	size = simple_strtoul(opt, &opt, 0);
858 
859 	if (opt) {
860 		switch (*opt) {
861 		case 'M':
862 		case 'm':
863 			size *= 1024;
864 		case 'K':
865 		case 'k':
866 			size *= 1024;
867 		default:
868 			break;
869 		}
870 	}
871 
872 	current_par.dram_size = size;
873 }
874 
875 static struct options {
876 	char *name;
877 	void (*parse)(char *opt);
878 } opt_table[] = {
879 	{ "mon",     acornfb_parse_mon     },
880 	{ "montype", acornfb_parse_montype },
881 	{ "dram",    acornfb_parse_dram    },
882 	{ NULL, NULL }
883 };
884 
885 static int acornfb_setup(char *options)
886 {
887 	struct options *optp;
888 	char *opt;
889 
890 	if (!options || !*options)
891 		return 0;
892 
893 	acornfb_init_fbinfo();
894 
895 	while ((opt = strsep(&options, ",")) != NULL) {
896 		if (!*opt)
897 			continue;
898 
899 		for (optp = opt_table; optp->name; optp++) {
900 			int optlen;
901 
902 			optlen = strlen(optp->name);
903 
904 			if (strncmp(opt, optp->name, optlen) == 0 &&
905 			    opt[optlen] == ':') {
906 				optp->parse(opt + optlen + 1);
907 				break;
908 			}
909 		}
910 
911 		if (!optp->name)
912 			printk(KERN_ERR "acornfb: unknown parameter: %s\n",
913 			       opt);
914 	}
915 	return 0;
916 }
917 
918 /*
919  * Detect type of monitor connected
920  *  For now, we just assume SVGA
921  */
922 static int acornfb_detect_monitortype(void)
923 {
924 	return 4;
925 }
926 
927 /*
928  * This enables the unused memory to be freed on older Acorn machines.
929  * We are freeing memory on behalf of the architecture initialisation
930  * code here.
931  */
932 static inline void
933 free_unused_pages(unsigned int virtual_start, unsigned int virtual_end)
934 {
935 	int mb_freed = 0;
936 
937 	/*
938 	 * Align addresses
939 	 */
940 	virtual_start = PAGE_ALIGN(virtual_start);
941 	virtual_end = PAGE_ALIGN(virtual_end);
942 
943 	while (virtual_start < virtual_end) {
944 		struct page *page;
945 
946 		/*
947 		 * Clear page reserved bit,
948 		 * set count to 1, and free
949 		 * the page.
950 		 */
951 		page = virt_to_page(virtual_start);
952 		__free_reserved_page(page);
953 
954 		virtual_start += PAGE_SIZE;
955 		mb_freed += PAGE_SIZE / 1024;
956 	}
957 
958 	printk("acornfb: freed %dK memory\n", mb_freed);
959 }
960 
961 static int acornfb_probe(struct platform_device *dev)
962 {
963 	unsigned long size;
964 	u_int h_sync, v_sync;
965 	int rc, i;
966 	char *option = NULL;
967 
968 	if (fb_get_options("acornfb", &option))
969 		return -ENODEV;
970 	acornfb_setup(option);
971 
972 	acornfb_init_fbinfo();
973 
974 	current_par.dev = &dev->dev;
975 
976 	if (current_par.montype == -1)
977 		current_par.montype = acornfb_detect_monitortype();
978 
979 	if (current_par.montype == -1 || current_par.montype > NR_MONTYPES)
980 		current_par.montype = 4;
981 
982 	if (current_par.montype >= 0) {
983 		fb_info.monspecs = monspecs[current_par.montype];
984 		fb_info.monspecs.dpms = current_par.dpms;
985 	}
986 
987 	/*
988 	 * Try to select a suitable default mode
989 	 */
990 	for (i = 0; i < ARRAY_SIZE(modedb); i++) {
991 		unsigned long hs;
992 
993 		hs = modedb[i].refresh *
994 		     (modedb[i].yres + modedb[i].upper_margin +
995 		      modedb[i].lower_margin + modedb[i].vsync_len);
996 		if (modedb[i].xres == DEFAULT_XRES &&
997 		    modedb[i].yres == DEFAULT_YRES &&
998 		    modedb[i].refresh >= fb_info.monspecs.vfmin &&
999 		    modedb[i].refresh <= fb_info.monspecs.vfmax &&
1000 		    hs                >= fb_info.monspecs.hfmin &&
1001 		    hs                <= fb_info.monspecs.hfmax) {
1002 			acornfb_default_mode = modedb[i];
1003 			break;
1004 		}
1005 	}
1006 
1007 	fb_info.screen_base    = (char *)SCREEN_BASE;
1008 	fb_info.fix.smem_start = SCREEN_START;
1009 	current_par.using_vram = 0;
1010 
1011 	/*
1012 	 * If vram_size is set, we are using VRAM in
1013 	 * a Risc PC.  However, if the user has specified
1014 	 * an amount of DRAM then use that instead.
1015 	 */
1016 	if (vram_size && !current_par.dram_size) {
1017 		size = vram_size;
1018 		current_par.vram_half_sam = vram_size / 1024;
1019 		current_par.using_vram = 1;
1020 	} else if (current_par.dram_size)
1021 		size = current_par.dram_size;
1022 	else
1023 		size = MAX_SIZE;
1024 
1025 	/*
1026 	 * Limit maximum screen size.
1027 	 */
1028 	if (size > MAX_SIZE)
1029 		size = MAX_SIZE;
1030 
1031 	size = PAGE_ALIGN(size);
1032 
1033 #if defined(HAS_VIDC20)
1034 	if (!current_par.using_vram) {
1035 		dma_addr_t handle;
1036 		void *base;
1037 
1038 		/*
1039 		 * RiscPC needs to allocate the DRAM memory
1040 		 * for the framebuffer if we are not using
1041 		 * VRAM.
1042 		 */
1043 		base = dma_alloc_wc(current_par.dev, size, &handle,
1044 				    GFP_KERNEL);
1045 		if (base == NULL) {
1046 			printk(KERN_ERR "acornfb: unable to allocate screen memory\n");
1047 			return -ENOMEM;
1048 		}
1049 
1050 		fb_info.screen_base = base;
1051 		fb_info.fix.smem_start = handle;
1052 	}
1053 #endif
1054 	fb_info.fix.smem_len = size;
1055 	current_par.palette_size   = VIDC_PALETTE_SIZE;
1056 
1057 	/*
1058 	 * Lookup the timing for this resolution.  If we can't
1059 	 * find it, then we can't restore it if we change
1060 	 * the resolution, so we disable this feature.
1061 	 */
1062 	do {
1063 		rc = fb_find_mode(&fb_info.var, &fb_info, NULL, modedb,
1064 				 ARRAY_SIZE(modedb),
1065 				 &acornfb_default_mode, DEFAULT_BPP);
1066 		/*
1067 		 * If we found an exact match, all ok.
1068 		 */
1069 		if (rc == 1)
1070 			break;
1071 
1072 		rc = fb_find_mode(&fb_info.var, &fb_info, NULL, NULL, 0,
1073 				  &acornfb_default_mode, DEFAULT_BPP);
1074 		/*
1075 		 * If we found an exact match, all ok.
1076 		 */
1077 		if (rc == 1)
1078 			break;
1079 
1080 		rc = fb_find_mode(&fb_info.var, &fb_info, NULL, modedb,
1081 				 ARRAY_SIZE(modedb),
1082 				 &acornfb_default_mode, DEFAULT_BPP);
1083 		if (rc)
1084 			break;
1085 
1086 		rc = fb_find_mode(&fb_info.var, &fb_info, NULL, NULL, 0,
1087 				  &acornfb_default_mode, DEFAULT_BPP);
1088 	} while (0);
1089 
1090 	/*
1091 	 * If we didn't find an exact match, try the
1092 	 * generic database.
1093 	 */
1094 	if (rc == 0) {
1095 		printk("Acornfb: no valid mode found\n");
1096 		return -EINVAL;
1097 	}
1098 
1099 	h_sync = 1953125000 / fb_info.var.pixclock;
1100 	h_sync = h_sync * 512 / (fb_info.var.xres + fb_info.var.left_margin +
1101 		 fb_info.var.right_margin + fb_info.var.hsync_len);
1102 	v_sync = h_sync / (fb_info.var.yres + fb_info.var.upper_margin +
1103 		 fb_info.var.lower_margin + fb_info.var.vsync_len);
1104 
1105 	printk(KERN_INFO "Acornfb: %dkB %cRAM, %s, using %dx%d, %d.%03dkHz, %dHz\n",
1106 		fb_info.fix.smem_len / 1024,
1107 		current_par.using_vram ? 'V' : 'D',
1108 		VIDC_NAME, fb_info.var.xres, fb_info.var.yres,
1109 		h_sync / 1000, h_sync % 1000, v_sync);
1110 
1111 	printk(KERN_INFO "Acornfb: Monitor: %d.%03d-%d.%03dkHz, %d-%dHz%s\n",
1112 		fb_info.monspecs.hfmin / 1000, fb_info.monspecs.hfmin % 1000,
1113 		fb_info.monspecs.hfmax / 1000, fb_info.monspecs.hfmax % 1000,
1114 		fb_info.monspecs.vfmin, fb_info.monspecs.vfmax,
1115 		fb_info.monspecs.dpms ? ", DPMS" : "");
1116 
1117 	if (fb_set_var(&fb_info, &fb_info.var))
1118 		printk(KERN_ERR "Acornfb: unable to set display parameters\n");
1119 
1120 	if (register_framebuffer(&fb_info) < 0)
1121 		return -EINVAL;
1122 	return 0;
1123 }
1124 
1125 static struct platform_driver acornfb_driver = {
1126 	.probe	= acornfb_probe,
1127 	.driver	= {
1128 		.name	= "acornfb",
1129 	},
1130 };
1131 
1132 static int __init acornfb_init(void)
1133 {
1134 	return platform_driver_register(&acornfb_driver);
1135 }
1136 
1137 module_init(acornfb_init);
1138 
1139 MODULE_AUTHOR("Russell King");
1140 MODULE_DESCRIPTION("VIDC 1/1a/20 framebuffer driver");
1141 MODULE_LICENSE("GPL");
1142