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 int mc68x328fb_init(void);
88 int mc68x328fb_setup(char *);
89
90 static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
91 struct fb_info *info);
92 static int mc68x328fb_set_par(struct fb_info *info);
93 static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
94 u_int transp, struct fb_info *info);
95 static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
96 struct fb_info *info);
97 static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma);
98
99 static const struct fb_ops mc68x328fb_ops = {
100 .fb_check_var = mc68x328fb_check_var,
101 .fb_set_par = mc68x328fb_set_par,
102 .fb_setcolreg = mc68x328fb_setcolreg,
103 .fb_pan_display = mc68x328fb_pan_display,
104 .fb_fillrect = cfb_fillrect,
105 .fb_copyarea = cfb_copyarea,
106 .fb_imageblit = cfb_imageblit,
107 .fb_mmap = mc68x328fb_mmap,
108 };
109
110 /*
111 * Internal routines
112 */
113
get_line_length(int xres_virtual,int bpp)114 static u_long get_line_length(int xres_virtual, int bpp)
115 {
116 u_long length;
117
118 length = xres_virtual * bpp;
119 length = (length + 31) & ~31;
120 length >>= 3;
121 return (length);
122 }
123
124 /*
125 * Setting the video mode has been split into two parts.
126 * First part, xxxfb_check_var, must not write anything
127 * to hardware, it should only verify and adjust var.
128 * This means it doesn't alter par but it does use hardware
129 * data from it to check this var.
130 */
131
mc68x328fb_check_var(struct fb_var_screeninfo * var,struct fb_info * info)132 static int mc68x328fb_check_var(struct fb_var_screeninfo *var,
133 struct fb_info *info)
134 {
135 u_long line_length;
136
137 /*
138 * FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
139 * as FB_VMODE_SMOOTH_XPAN is only used internally
140 */
141
142 if (var->vmode & FB_VMODE_CONUPDATE) {
143 var->vmode |= FB_VMODE_YWRAP;
144 var->xoffset = info->var.xoffset;
145 var->yoffset = info->var.yoffset;
146 }
147
148 /*
149 * Some very basic checks
150 */
151 if (!var->xres)
152 var->xres = 1;
153 if (!var->yres)
154 var->yres = 1;
155 if (var->xres > var->xres_virtual)
156 var->xres_virtual = var->xres;
157 if (var->yres > var->yres_virtual)
158 var->yres_virtual = var->yres;
159 if (var->bits_per_pixel <= 1)
160 var->bits_per_pixel = 1;
161 else if (var->bits_per_pixel <= 8)
162 var->bits_per_pixel = 8;
163 else if (var->bits_per_pixel <= 16)
164 var->bits_per_pixel = 16;
165 else if (var->bits_per_pixel <= 24)
166 var->bits_per_pixel = 24;
167 else if (var->bits_per_pixel <= 32)
168 var->bits_per_pixel = 32;
169 else
170 return -EINVAL;
171
172 if (var->xres_virtual < var->xoffset + var->xres)
173 var->xres_virtual = var->xoffset + var->xres;
174 if (var->yres_virtual < var->yoffset + var->yres)
175 var->yres_virtual = var->yoffset + var->yres;
176
177 /*
178 * Memory limit
179 */
180 line_length =
181 get_line_length(var->xres_virtual, var->bits_per_pixel);
182 if (line_length * var->yres_virtual > videomemorysize)
183 return -ENOMEM;
184
185 /*
186 * Now that we checked it we alter var. The reason being is that the video
187 * mode passed in might not work but slight changes to it might make it
188 * work. This way we let the user know what is acceptable.
189 */
190 switch (var->bits_per_pixel) {
191 case 1:
192 var->red.offset = 0;
193 var->red.length = 1;
194 var->green.offset = 0;
195 var->green.length = 1;
196 var->blue.offset = 0;
197 var->blue.length = 1;
198 var->transp.offset = 0;
199 var->transp.length = 0;
200 break;
201 case 8:
202 var->red.offset = 0;
203 var->red.length = 8;
204 var->green.offset = 0;
205 var->green.length = 8;
206 var->blue.offset = 0;
207 var->blue.length = 8;
208 var->transp.offset = 0;
209 var->transp.length = 0;
210 break;
211 case 16: /* RGBA 5551 */
212 if (var->transp.length) {
213 var->red.offset = 0;
214 var->red.length = 5;
215 var->green.offset = 5;
216 var->green.length = 5;
217 var->blue.offset = 10;
218 var->blue.length = 5;
219 var->transp.offset = 15;
220 var->transp.length = 1;
221 } else { /* RGB 565 */
222 var->red.offset = 0;
223 var->red.length = 5;
224 var->green.offset = 5;
225 var->green.length = 6;
226 var->blue.offset = 11;
227 var->blue.length = 5;
228 var->transp.offset = 0;
229 var->transp.length = 0;
230 }
231 break;
232 case 24: /* RGB 888 */
233 var->red.offset = 0;
234 var->red.length = 8;
235 var->green.offset = 8;
236 var->green.length = 8;
237 var->blue.offset = 16;
238 var->blue.length = 8;
239 var->transp.offset = 0;
240 var->transp.length = 0;
241 break;
242 case 32: /* RGBA 8888 */
243 var->red.offset = 0;
244 var->red.length = 8;
245 var->green.offset = 8;
246 var->green.length = 8;
247 var->blue.offset = 16;
248 var->blue.length = 8;
249 var->transp.offset = 24;
250 var->transp.length = 8;
251 break;
252 }
253 var->red.msb_right = 0;
254 var->green.msb_right = 0;
255 var->blue.msb_right = 0;
256 var->transp.msb_right = 0;
257
258 return 0;
259 }
260
261 /* This routine actually sets the video mode. It's in here where we
262 * the hardware state info->par and fix which can be affected by the
263 * change in par. For this driver it doesn't do much.
264 */
mc68x328fb_set_par(struct fb_info * info)265 static int mc68x328fb_set_par(struct fb_info *info)
266 {
267 info->fix.line_length = get_line_length(info->var.xres_virtual,
268 info->var.bits_per_pixel);
269 return 0;
270 }
271
272 /*
273 * Set a single color register. The values supplied are already
274 * rounded down to the hardware's capabilities (according to the
275 * entries in the var structure). Return != 0 for invalid regno.
276 */
277
mc68x328fb_setcolreg(u_int regno,u_int red,u_int green,u_int blue,u_int transp,struct fb_info * info)278 static int mc68x328fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
279 u_int transp, struct fb_info *info)
280 {
281 if (regno >= 256) /* no. of hw registers */
282 return 1;
283 /*
284 * Program hardware... do anything you want with transp
285 */
286
287 /* grayscale works only partially under directcolor */
288 if (info->var.grayscale) {
289 /* grayscale = 0.30*R + 0.59*G + 0.11*B */
290 red = green = blue =
291 (red * 77 + green * 151 + blue * 28) >> 8;
292 }
293
294 /* Directcolor:
295 * var->{color}.offset contains start of bitfield
296 * var->{color}.length contains length of bitfield
297 * {hardwarespecific} contains width of RAMDAC
298 * cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
299 * RAMDAC[X] is programmed to (red, green, blue)
300 *
301 * Pseudocolor:
302 * uses offset = 0 && length = RAMDAC register width.
303 * var->{color}.offset is 0
304 * var->{color}.length contains width of DAC
305 * cmap is not used
306 * RAMDAC[X] is programmed to (red, green, blue)
307 * Truecolor:
308 * does not use DAC. Usually 3 are present.
309 * var->{color}.offset contains start of bitfield
310 * var->{color}.length contains length of bitfield
311 * cmap is programmed to (red << red.offset) | (green << green.offset) |
312 * (blue << blue.offset) | (transp << transp.offset)
313 * RAMDAC does not exist
314 */
315 #define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
316 switch (info->fix.visual) {
317 case FB_VISUAL_TRUECOLOR:
318 case FB_VISUAL_PSEUDOCOLOR:
319 red = CNVT_TOHW(red, info->var.red.length);
320 green = CNVT_TOHW(green, info->var.green.length);
321 blue = CNVT_TOHW(blue, info->var.blue.length);
322 transp = CNVT_TOHW(transp, info->var.transp.length);
323 break;
324 case FB_VISUAL_DIRECTCOLOR:
325 red = CNVT_TOHW(red, 8); /* expect 8 bit DAC */
326 green = CNVT_TOHW(green, 8);
327 blue = CNVT_TOHW(blue, 8);
328 /* hey, there is bug in transp handling... */
329 transp = CNVT_TOHW(transp, 8);
330 break;
331 }
332 #undef CNVT_TOHW
333 /* Truecolor has hardware independent palette */
334 if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
335 u32 v;
336
337 if (regno >= 16)
338 return 1;
339
340 v = (red << info->var.red.offset) |
341 (green << info->var.green.offset) |
342 (blue << info->var.blue.offset) |
343 (transp << info->var.transp.offset);
344 switch (info->var.bits_per_pixel) {
345 case 8:
346 break;
347 case 16:
348 ((u32 *) (info->pseudo_palette))[regno] = v;
349 break;
350 case 24:
351 case 32:
352 ((u32 *) (info->pseudo_palette))[regno] = v;
353 break;
354 }
355 return 0;
356 }
357 return 0;
358 }
359
360 /*
361 * Pan or Wrap the Display
362 *
363 * This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
364 */
365
mc68x328fb_pan_display(struct fb_var_screeninfo * var,struct fb_info * info)366 static int mc68x328fb_pan_display(struct fb_var_screeninfo *var,
367 struct fb_info *info)
368 {
369 if (var->vmode & FB_VMODE_YWRAP) {
370 if (var->yoffset < 0
371 || var->yoffset >= info->var.yres_virtual
372 || var->xoffset)
373 return -EINVAL;
374 } else {
375 if (var->xoffset + info->var.xres > info->var.xres_virtual ||
376 var->yoffset + info->var.yres > info->var.yres_virtual)
377 return -EINVAL;
378 }
379 info->var.xoffset = var->xoffset;
380 info->var.yoffset = var->yoffset;
381 if (var->vmode & FB_VMODE_YWRAP)
382 info->var.vmode |= FB_VMODE_YWRAP;
383 else
384 info->var.vmode &= ~FB_VMODE_YWRAP;
385 return 0;
386 }
387
388 /*
389 * Most drivers don't need their own mmap function
390 */
391
mc68x328fb_mmap(struct fb_info * info,struct vm_area_struct * vma)392 static int mc68x328fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
393 {
394 #ifndef MMU
395 /* this is uClinux (no MMU) specific code */
396
397 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
398 vma->vm_start = videomemory;
399
400 return 0;
401 #else
402 return -EINVAL;
403 #endif
404 }
405
mc68x328fb_setup(char * options)406 int __init mc68x328fb_setup(char *options)
407 {
408 if (!options || !*options)
409 return 1;
410 return 1;
411 }
412
413 /*
414 * Initialisation
415 */
416
mc68x328fb_init(void)417 int __init mc68x328fb_init(void)
418 {
419 #ifndef MODULE
420 char *option = NULL;
421
422 if (fb_get_options("68328fb", &option))
423 return -ENODEV;
424 mc68x328fb_setup(option);
425 #endif
426 /*
427 * initialize the default mode from the LCD controller registers
428 */
429 mc68x328fb_default.xres = LXMAX;
430 mc68x328fb_default.yres = LYMAX+1;
431 mc68x328fb_default.xres_virtual = mc68x328fb_default.xres;
432 mc68x328fb_default.yres_virtual = mc68x328fb_default.yres;
433 mc68x328fb_default.bits_per_pixel = 1 + (LPICF & 0x01);
434 videomemory = LSSA;
435 videomemorysize = (mc68x328fb_default.xres_virtual+7) / 8 *
436 mc68x328fb_default.yres_virtual * mc68x328fb_default.bits_per_pixel;
437
438 fb_info.screen_base = (void *)videomemory;
439 fb_info.fbops = &mc68x328fb_ops;
440 fb_info.var = mc68x328fb_default;
441 fb_info.fix = mc68x328fb_fix;
442 fb_info.fix.smem_start = videomemory;
443 fb_info.fix.smem_len = videomemorysize;
444 fb_info.fix.line_length =
445 get_line_length(mc68x328fb_default.xres_virtual, mc68x328fb_default.bits_per_pixel);
446 fb_info.fix.visual = (mc68x328fb_default.bits_per_pixel) == 1 ?
447 FB_VISUAL_MONO10 : FB_VISUAL_PSEUDOCOLOR;
448 if (fb_info.var.bits_per_pixel == 1) {
449 fb_info.var.red.length = fb_info.var.green.length = fb_info.var.blue.length = 1;
450 fb_info.var.red.offset = fb_info.var.green.offset = fb_info.var.blue.offset = 0;
451 }
452 fb_info.pseudo_palette = &mc68x328fb_pseudo_palette;
453 fb_info.flags = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
454
455 if (fb_alloc_cmap(&fb_info.cmap, 256, 0))
456 return -ENOMEM;
457
458 if (register_framebuffer(&fb_info) < 0) {
459 fb_dealloc_cmap(&fb_info.cmap);
460 return -EINVAL;
461 }
462
463 fb_info(&fb_info, "%s frame buffer device\n", fb_info.fix.id);
464 fb_info(&fb_info, "%dx%dx%d at 0x%08lx\n",
465 mc68x328fb_default.xres_virtual,
466 mc68x328fb_default.yres_virtual,
467 1 << mc68x328fb_default.bits_per_pixel, videomemory);
468
469 return 0;
470 }
471
472 module_init(mc68x328fb_init);
473
474 #ifdef MODULE
475
mc68x328fb_cleanup(void)476 static void __exit mc68x328fb_cleanup(void)
477 {
478 unregister_framebuffer(&fb_info);
479 fb_dealloc_cmap(&fb_info.cmap);
480 }
481
482 module_exit(mc68x328fb_cleanup);
483
484 MODULE_LICENSE("GPL");
485 #endif /* MODULE */
486