1 /*
2 * linux/drivers/video/68328fb.c -- Low level implementation of the
3 * mc68x328 LCD frame buffer device
4 *
5 * Copyright (C) 2003 Georges Menie
6 *
7 * This driver assumes an already configured controller (e.g. from config.c)
8 * Keep the code clean of board specific initialization.
9 *
10 * This code has not been tested with colors, colormap management functions
11 * are minimal (no colormap data written to the 68328 registers...)
12 *
13 * initial version of this driver:
14 * Copyright (C) 1998,1999 Kenneth Albanowski <kjahds@kjahds.com>,
15 * The Silver Hammer Group, Ltd.
16 *
17 * this version is based on :
18 *
19 * linux/drivers/video/vfb.c -- Virtual frame buffer device
20 *
21 * Copyright (C) 2002 James Simmons
22 *
23 * Copyright (C) 1997 Geert Uytterhoeven
24 *
25 * This file is subject to the terms and conditions of the GNU General Public
26 * License. See the file COPYING in the main directory of this archive for
27 * more details.
28 */
29
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32 #include <linux/errno.h>
33 #include <linux/string.h>
34 #include <linux/mm.h>
35 #include <linux/vmalloc.h>
36 #include <linux/delay.h>
37 #include <linux/interrupt.h>
38 #include <linux/uaccess.h>
39 #include <linux/fb.h>
40 #include <linux/init.h>
41
42 #if defined(CONFIG_M68VZ328)
43 #include <asm/MC68VZ328.h>
44 #elif defined(CONFIG_M68EZ328)
45 #include <asm/MC68EZ328.h>
46 #elif defined(CONFIG_M68328)
47 #include <asm/MC68328.h>
48 #else
49 #error wrong architecture for the MC68x328 frame buffer device
50 #endif
51
52 static u_long videomemory;
53 static u_long videomemorysize;
54
55 static struct fb_info fb_info;
56 static u32 mc68x328fb_pseudo_palette[16];
57
58 static struct fb_var_screeninfo mc68x328fb_default __initdata = {
59 .red = { 0, 8, 0 },
60 .green = { 0, 8, 0 },
61 .blue = { 0, 8, 0 },
62 .activate = FB_ACTIVATE_TEST,
63 .height = -1,
64 .width = -1,
65 .pixclock = 20000,
66 .left_margin = 64,
67 .right_margin = 64,
68 .upper_margin = 32,
69 .lower_margin = 32,
70 .hsync_len = 64,
71 .vsync_len = 2,
72 .vmode = FB_VMODE_NONINTERLACED,
73 };
74
75 static const struct fb_fix_screeninfo mc68x328fb_fix __initconst = {
76 .id = "68328fb",
77 .type = FB_TYPE_PACKED_PIXELS,
78 .xpanstep = 1,
79 .ypanstep = 1,
80 .ywrapstep = 1,
81 .accel = FB_ACCEL_NONE,
82 };
83
84 /*
85 * Interface used by the world
86 */
87 static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
88 struct fb_info *info);
89 static int mc68x328fb_set_par(struct fb_info *info);
90 static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
91 u_int transp, struct fb_info *info);
92 static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
93 struct fb_info *info);
94 static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma);
95
96 static const struct fb_ops mc68x328fb_ops = {
97 .owner = THIS_MODULE,
98 .fb_check_var = mc68x328fb_check_var,
99 .fb_set_par = mc68x328fb_set_par,
100 .fb_setcolreg = mc68x328fb_setcolreg,
101 .fb_pan_display = mc68x328fb_pan_display,
102 .fb_fillrect = cfb_fillrect,
103 .fb_copyarea = cfb_copyarea,
104 .fb_imageblit = cfb_imageblit,
105 .fb_mmap = mc68x328fb_mmap,
106 };
107
108 /*
109 * Internal routines
110 */
111
get_line_length(int xres_virtual,int bpp)112 static u_long get_line_length(int xres_virtual, int bpp)
113 {
114 u_long length;
115
116 length = xres_virtual * bpp;
117 length = (length + 31) & ~31;
118 length >>= 3;
119 return (length);
120 }
121
122 /*
123 * Setting the video mode has been split into two parts.
124 * First part, xxxfb_check_var, must not write anything
125 * to hardware, it should only verify and adjust var.
126 * This means it doesn't alter par but it does use hardware
127 * data from it to check this var.
128 */
129
mc68x328fb_check_var(struct fb_var_screeninfo * var,struct fb_info * info)130 static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
131 struct fb_info *info)
132 {
133 u_long line_length;
134
135 /*
136 * FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
137 * as FB_VMODE_SMOOTH_XPAN is only used internally
138 */
139
140 if (var->vmode & FB_VMODE_CONUPDATE) {
141 var->vmode |= FB_VMODE_YWRAP;
142 var->xoffset = info->var.xoffset;
143 var->yoffset = info->var.yoffset;
144 }
145
146 /*
147 * Some very basic checks
148 */
149 if (!var->xres)
150 var->xres = 1;
151 if (!var->yres)
152 var->yres = 1;
153 if (var->xres > var->xres_virtual)
154 var->xres_virtual = var->xres;
155 if (var->yres > var->yres_virtual)
156 var->yres_virtual = var->yres;
157 if (var->bits_per_pixel <= 1)
158 var->bits_per_pixel = 1;
159 else if (var->bits_per_pixel <= 8)
160 var->bits_per_pixel = 8;
161 else if (var->bits_per_pixel <= 16)
162 var->bits_per_pixel = 16;
163 else if (var->bits_per_pixel <= 24)
164 var->bits_per_pixel = 24;
165 else if (var->bits_per_pixel <= 32)
166 var->bits_per_pixel = 32;
167 else
168 return -EINVAL;
169
170 if (var->xres_virtual < var->xoffset + var->xres)
171 var->xres_virtual = var->xoffset + var->xres;
172 if (var->yres_virtual < var->yoffset + var->yres)
173 var->yres_virtual = var->yoffset + var->yres;
174
175 /*
176 * Memory limit
177 */
178 line_length =
179 get_line_length(var->xres_virtual, var->bits_per_pixel);
180 if (line_length * var->yres_virtual > videomemorysize)
181 return -ENOMEM;
182
183 /*
184 * Now that we checked it we alter var. The reason being is that the video
185 * mode passed in might not work but slight changes to it might make it
186 * work. This way we let the user know what is acceptable.
187 */
188 switch (var->bits_per_pixel) {
189 case 1:
190 var->red.offset = 0;
191 var->red.length = 1;
192 var->green.offset = 0;
193 var->green.length = 1;
194 var->blue.offset = 0;
195 var->blue.length = 1;
196 var->transp.offset = 0;
197 var->transp.length = 0;
198 break;
199 case 8:
200 var->red.offset = 0;
201 var->red.length = 8;
202 var->green.offset = 0;
203 var->green.length = 8;
204 var->blue.offset = 0;
205 var->blue.length = 8;
206 var->transp.offset = 0;
207 var->transp.length = 0;
208 break;
209 case 16: /* RGBA 5551 */
210 if (var->transp.length) {
211 var->red.offset = 0;
212 var->red.length = 5;
213 var->green.offset = 5;
214 var->green.length = 5;
215 var->blue.offset = 10;
216 var->blue.length = 5;
217 var->transp.offset = 15;
218 var->transp.length = 1;
219 } else { /* RGB 565 */
220 var->red.offset = 0;
221 var->red.length = 5;
222 var->green.offset = 5;
223 var->green.length = 6;
224 var->blue.offset = 11;
225 var->blue.length = 5;
226 var->transp.offset = 0;
227 var->transp.length = 0;
228 }
229 break;
230 case 24: /* RGB 888 */
231 var->red.offset = 0;
232 var->red.length = 8;
233 var->green.offset = 8;
234 var->green.length = 8;
235 var->blue.offset = 16;
236 var->blue.length = 8;
237 var->transp.offset = 0;
238 var->transp.length = 0;
239 break;
240 case 32: /* RGBA 8888 */
241 var->red.offset = 0;
242 var->red.length = 8;
243 var->green.offset = 8;
244 var->green.length = 8;
245 var->blue.offset = 16;
246 var->blue.length = 8;
247 var->transp.offset = 24;
248 var->transp.length = 8;
249 break;
250 }
251 var->red.msb_right = 0;
252 var->green.msb_right = 0;
253 var->blue.msb_right = 0;
254 var->transp.msb_right = 0;
255
256 return 0;
257 }
258
259 /* This routine actually sets the video mode. It's in here where we
260 * the hardware state info->par and fix which can be affected by the
261 * change in par. For this driver it doesn't do much.
262 */
mc68x328fb_set_par(struct fb_info * info)263 static int mc68x328fb_set_par(struct fb_info *info)
264 {
265 info->fix.line_length = get_line_length(info->var.xres_virtual,
266 info->var.bits_per_pixel);
267 return 0;
268 }
269
270 /*
271 * Set a single color register. The values supplied are already
272 * rounded down to the hardware's capabilities (according to the
273 * entries in the var structure). Return != 0 for invalid regno.
274 */
275
mc68x328fb_setcolreg(u_int regno,u_int red,u_int green,u_int blue,u_int transp,struct fb_info * info)276 static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
277 u_int transp, struct fb_info *info)
278 {
279 if (regno >= 256) /* no. of hw registers */
280 return 1;
281 /*
282 * Program hardware... do anything you want with transp
283 */
284
285 /* grayscale works only partially under directcolor */
286 if (info->var.grayscale) {
287 /* grayscale = 0.30*R + 0.59*G + 0.11*B */
288 red = green = blue =
289 (red * 77 + green * 151 + blue * 28) >> 8;
290 }
291
292 /* Directcolor:
293 * var->{color}.offset contains start of bitfield
294 * var->{color}.length contains length of bitfield
295 * {hardwarespecific} contains width of RAMDAC
296 * cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
297 * RAMDAC[X] is programmed to (red, green, blue)
298 *
299 * Pseudocolor:
300 * uses offset = 0 && length = RAMDAC register width.
301 * var->{color}.offset is 0
302 * var->{color}.length contains width of DAC
303 * cmap is not used
304 * RAMDAC[X] is programmed to (red, green, blue)
305 * Truecolor:
306 * does not use DAC. Usually 3 are present.
307 * var->{color}.offset contains start of bitfield
308 * var->{color}.length contains length of bitfield
309 * cmap is programmed to (red << red.offset) | (green << green.offset) |
310 * (blue << blue.offset) | (transp << transp.offset)
311 * RAMDAC does not exist
312 */
313 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
314 switch (info->fix.visual) {
315 case FB_VISUAL_TRUECOLOR:
316 case FB_VISUAL_PSEUDOCOLOR:
317 red = CNVT_TOHW(red, info->var.red.length);
318 green = CNVT_TOHW(green, info->var.green.length);
319 blue = CNVT_TOHW(blue, info->var.blue.length);
320 transp = CNVT_TOHW(transp, info->var.transp.length);
321 break;
322 case FB_VISUAL_DIRECTCOLOR:
323 red = CNVT_TOHW(red, 8); /* expect 8 bit DAC */
324 green = CNVT_TOHW(green, 8);
325 blue = CNVT_TOHW(blue, 8);
326 /* hey, there is bug in transp handling... */
327 transp = CNVT_TOHW(transp, 8);
328 break;
329 }
330 #undef CNVT_TOHW
331 /* Truecolor has hardware independent palette */
332 if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
333 u32 v;
334
335 if (regno >= 16)
336 return 1;
337
338 v = (red << info->var.red.offset) |
339 (green << info->var.green.offset) |
340 (blue << info->var.blue.offset) |
341 (transp << info->var.transp.offset);
342 switch (info->var.bits_per_pixel) {
343 case 8:
344 break;
345 case 16:
346 ((u32 *) (info->pseudo_palette))[regno] = v;
347 break;
348 case 24:
349 case 32:
350 ((u32 *) (info->pseudo_palette))[regno] = v;
351 break;
352 }
353 return 0;
354 }
355 return 0;
356 }
357
358 /*
359 * Pan or Wrap the Display
360 *
361 * This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
362 */
363
mc68x328fb_pan_display(struct fb_var_screeninfo * var,struct fb_info * info)364 static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
365 struct fb_info *info)
366 {
367 if (var->vmode & FB_VMODE_YWRAP) {
368 if (var->yoffset < 0
369 || var->yoffset >= info->var.yres_virtual
370 || var->xoffset)
371 return -EINVAL;
372 } else {
373 if (var->xoffset + info->var.xres > info->var.xres_virtual ||
374 var->yoffset + info->var.yres > info->var.yres_virtual)
375 return -EINVAL;
376 }
377 info->var.xoffset = var->xoffset;
378 info->var.yoffset = var->yoffset;
379 if (var->vmode & FB_VMODE_YWRAP)
380 info->var.vmode |= FB_VMODE_YWRAP;
381 else
382 info->var.vmode &= ~FB_VMODE_YWRAP;
383 return 0;
384 }
385
386 /*
387 * Most drivers don't need their own mmap function
388 */
389
mc68x328fb_mmap(struct fb_info * info,struct vm_area_struct * vma)390 static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
391 {
392 #ifndef MMU
393 /* this is uClinux (no MMU) specific code */
394
395 vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
396 vma->vm_start = videomemory;
397
398 return 0;
399 #else
400 return -EINVAL;
401 #endif
402 }
403
mc68x328fb_setup(char * options)404 static int __init mc68x328fb_setup(char *options)
405 {
406 if (!options || !*options)
407 return 1;
408 return 1;
409 }
410
411 /*
412 * Initialisation
413 */
414
mc68x328fb_init(void)415 static int __init mc68x328fb_init(void)
416 {
417 #ifndef MODULE
418 char *option = NULL;
419
420 if (fb_get_options("68328fb", &option))
421 return -ENODEV;
422 mc68x328fb_setup(option);
423 #endif
424 /*
425 * initialize the default mode from the LCD controller registers
426 */
427 mc68x328fb_default.xres = LXMAX;
428 mc68x328fb_default.yres = LYMAX+1;
429 mc68x328fb_default.xres_virtual = mc68x328fb_default.xres;
430 mc68x328fb_default.yres_virtual = mc68x328fb_default.yres;
431 mc68x328fb_default.bits_per_pixel = 1 + (LPICF & 0x01);
432 videomemory = LSSA;
433 videomemorysize = (mc68x328fb_default.xres_virtual+7) / 8 *
434 mc68x328fb_default.yres_virtual * mc68x328fb_default.bits_per_pixel;
435
436 fb_info.screen_base = (void *)videomemory;
437 fb_info.fbops = &mc68x328fb_ops;
438 fb_info.var = mc68x328fb_default;
439 fb_info.fix = mc68x328fb_fix;
440 fb_info.fix.smem_start = videomemory;
441 fb_info.fix.smem_len = videomemorysize;
442 fb_info.fix.line_length =
443 get_line_length(mc68x328fb_default.xres_virtual, mc68x328fb_default.bits_per_pixel);
444 fb_info.fix.visual = (mc68x328fb_default.bits_per_pixel) == 1 ?
445 FB_VISUAL_MONO10 : FB_VISUAL_PSEUDOCOLOR;
446 if (fb_info.var.bits_per_pixel == 1) {
447 fb_info.var.red.length = fb_info.var.green.length = fb_info.var.blue.length = 1;
448 fb_info.var.red.offset = fb_info.var.green.offset = fb_info.var.blue.offset = 0;
449 }
450 fb_info.pseudo_palette = &mc68x328fb_pseudo_palette;
451 fb_info.flags = FBINFO_HWACCEL_YPAN;
452
453 if (fb_alloc_cmap(&fb_info.cmap, 256, 0))
454 return -ENOMEM;
455
456 if (register_framebuffer(&fb_info) < 0) {
457 fb_dealloc_cmap(&fb_info.cmap);
458 return -EINVAL;
459 }
460
461 fb_info(&fb_info, "%s frame buffer device\n", fb_info.fix.id);
462 fb_info(&fb_info, "%dx%dx%d at 0x%08lx\n",
463 mc68x328fb_default.xres_virtual,
464 mc68x328fb_default.yres_virtual,
465 1 << mc68x328fb_default.bits_per_pixel, videomemory);
466
467 return 0;
468 }
469
470 module_init(mc68x328fb_init);
471
472 #ifdef MODULE
473
mc68x328fb_cleanup(void)474 static void __exit mc68x328fb_cleanup(void)
475 {
476 unregister_framebuffer(&fb_info);
477 fb_dealloc_cmap(&fb_info.cmap);
478 }
479
480 module_exit(mc68x328fb_cleanup);
481
482 MODULE_LICENSE("GPL");
483 #endif /* MODULE */
484