1 /*
2 * Driver for Aeroflex Gaisler SVGACTRL framebuffer device.
3 *
4 * 2011 (c) Aeroflex Gaisler AB
5 *
6 * Full documentation of the core can be found here:
7 * http://www.gaisler.com/products/grlib/grip.pdf
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2 of the License, or (at your
12 * option) any later version.
13 *
14 * Contributors: Kristoffer Glembo <kristoffer@gaisler.com>
15 *
16 */
17
18 #include <linux/platform_device.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/of_platform.h>
21 #include <linux/of_device.h>
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/string.h>
25 #include <linux/delay.h>
26 #include <linux/errno.h>
27 #include <linux/init.h>
28 #include <linux/slab.h>
29 #include <linux/tty.h>
30 #include <linux/mm.h>
31 #include <linux/fb.h>
32 #include <linux/io.h>
33
34 struct grvga_regs {
35 u32 status; /* 0x00 */
36 u32 video_length; /* 0x04 */
37 u32 front_porch; /* 0x08 */
38 u32 sync_length; /* 0x0C */
39 u32 line_length; /* 0x10 */
40 u32 fb_pos; /* 0x14 */
41 u32 clk_vector[4]; /* 0x18 */
42 u32 clut; /* 0x20 */
43 };
44
45 struct grvga_par {
46 struct grvga_regs *regs;
47 u32 color_palette[16]; /* 16 entry pseudo palette used by fbcon in true color mode */
48 int clk_sel;
49 int fb_alloced; /* = 1 if framebuffer is allocated in main memory */
50 };
51
52
53 static const struct fb_videomode grvga_modedb[] = {
54 {
55 /* 640x480 @ 60 Hz */
56 NULL, 60, 640, 480, 40000, 48, 16, 39, 11, 96, 2,
57 0, FB_VMODE_NONINTERLACED
58 }, {
59 /* 800x600 @ 60 Hz */
60 NULL, 60, 800, 600, 25000, 88, 40, 23, 1, 128, 4,
61 0, FB_VMODE_NONINTERLACED
62 }, {
63 /* 800x600 @ 72 Hz */
64 NULL, 72, 800, 600, 20000, 64, 56, 23, 37, 120, 6,
65 0, FB_VMODE_NONINTERLACED
66 }, {
67 /* 1024x768 @ 60 Hz */
68 NULL, 60, 1024, 768, 15385, 160, 24, 29, 3, 136, 6,
69 0, FB_VMODE_NONINTERLACED
70 }
71 };
72
73 static struct fb_fix_screeninfo grvga_fix = {
74 .id = "AG SVGACTRL",
75 .type = FB_TYPE_PACKED_PIXELS,
76 .visual = FB_VISUAL_PSEUDOCOLOR,
77 .xpanstep = 0,
78 .ypanstep = 1,
79 .ywrapstep = 0,
80 .accel = FB_ACCEL_NONE,
81 };
82
grvga_check_var(struct fb_var_screeninfo * var,struct fb_info * info)83 static int grvga_check_var(struct fb_var_screeninfo *var,
84 struct fb_info *info)
85 {
86 struct grvga_par *par = info->par;
87 int i;
88
89 if (!var->xres)
90 var->xres = 1;
91 if (!var->yres)
92 var->yres = 1;
93 if (var->bits_per_pixel <= 8)
94 var->bits_per_pixel = 8;
95 else if (var->bits_per_pixel <= 16)
96 var->bits_per_pixel = 16;
97 else if (var->bits_per_pixel <= 24)
98 var->bits_per_pixel = 24;
99 else if (var->bits_per_pixel <= 32)
100 var->bits_per_pixel = 32;
101 else
102 return -EINVAL;
103
104 var->xres_virtual = var->xres;
105 var->yres_virtual = 2*var->yres;
106
107 if (info->fix.smem_len) {
108 if ((var->yres_virtual*var->xres_virtual*var->bits_per_pixel/8) > info->fix.smem_len)
109 return -ENOMEM;
110 }
111
112 /* Which clocks that are available can be read out in these registers */
113 for (i = 0; i <= 3 ; i++) {
114 if (var->pixclock == par->regs->clk_vector[i])
115 break;
116 }
117 if (i <= 3)
118 par->clk_sel = i;
119 else
120 return -EINVAL;
121
122 switch (info->var.bits_per_pixel) {
123 case 8:
124 var->red = (struct fb_bitfield) {0, 8, 0}; /* offset, length, msb-right */
125 var->green = (struct fb_bitfield) {0, 8, 0};
126 var->blue = (struct fb_bitfield) {0, 8, 0};
127 var->transp = (struct fb_bitfield) {0, 0, 0};
128 break;
129 case 16:
130 var->red = (struct fb_bitfield) {11, 5, 0};
131 var->green = (struct fb_bitfield) {5, 6, 0};
132 var->blue = (struct fb_bitfield) {0, 5, 0};
133 var->transp = (struct fb_bitfield) {0, 0, 0};
134 break;
135 case 24:
136 case 32:
137 var->red = (struct fb_bitfield) {16, 8, 0};
138 var->green = (struct fb_bitfield) {8, 8, 0};
139 var->blue = (struct fb_bitfield) {0, 8, 0};
140 var->transp = (struct fb_bitfield) {24, 8, 0};
141 break;
142 default:
143 return -EINVAL;
144 }
145
146 return 0;
147 }
148
grvga_set_par(struct fb_info * info)149 static int grvga_set_par(struct fb_info *info)
150 {
151
152 u32 func = 0;
153 struct grvga_par *par = info->par;
154
155 __raw_writel(((info->var.yres - 1) << 16) | (info->var.xres - 1),
156 &par->regs->video_length);
157
158 __raw_writel((info->var.lower_margin << 16) | (info->var.right_margin),
159 &par->regs->front_porch);
160
161 __raw_writel((info->var.vsync_len << 16) | (info->var.hsync_len),
162 &par->regs->sync_length);
163
164 __raw_writel(((info->var.yres + info->var.lower_margin + info->var.upper_margin + info->var.vsync_len - 1) << 16) |
165 (info->var.xres + info->var.right_margin + info->var.left_margin + info->var.hsync_len - 1),
166 &par->regs->line_length);
167
168 switch (info->var.bits_per_pixel) {
169 case 8:
170 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
171 func = 1;
172 break;
173 case 16:
174 info->fix.visual = FB_VISUAL_TRUECOLOR;
175 func = 2;
176 break;
177 case 24:
178 case 32:
179 info->fix.visual = FB_VISUAL_TRUECOLOR;
180 func = 3;
181 break;
182 default:
183 return -EINVAL;
184 }
185
186 __raw_writel((par->clk_sel << 6) | (func << 4) | 1,
187 &par->regs->status);
188
189 info->fix.line_length = (info->var.xres_virtual*info->var.bits_per_pixel)/8;
190 return 0;
191 }
192
grvga_setcolreg(unsigned regno,unsigned red,unsigned green,unsigned blue,unsigned transp,struct fb_info * info)193 static int grvga_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue, unsigned transp, struct fb_info *info)
194 {
195 struct grvga_par *par;
196 par = info->par;
197
198 if (regno >= 256) /* Size of CLUT */
199 return -EINVAL;
200
201 if (info->var.grayscale) {
202 /* grayscale = 0.30*R + 0.59*G + 0.11*B */
203 red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
204 }
205
206
207
208 #define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16)
209
210 red = CNVT_TOHW(red, info->var.red.length);
211 green = CNVT_TOHW(green, info->var.green.length);
212 blue = CNVT_TOHW(blue, info->var.blue.length);
213 transp = CNVT_TOHW(transp, info->var.transp.length);
214
215 #undef CNVT_TOHW
216
217 /* In PSEUDOCOLOR we use the hardware CLUT */
218 if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR)
219 __raw_writel((regno << 24) | (red << 16) | (green << 8) | blue,
220 &par->regs->clut);
221
222 /* Truecolor uses the pseudo palette */
223 else if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
224 u32 v;
225 if (regno >= 16)
226 return -EINVAL;
227
228
229 v = (red << info->var.red.offset) |
230 (green << info->var.green.offset) |
231 (blue << info->var.blue.offset) |
232 (transp << info->var.transp.offset);
233
234 ((u32 *) (info->pseudo_palette))[regno] = v;
235 }
236 return 0;
237 }
238
grvga_pan_display(struct fb_var_screeninfo * var,struct fb_info * info)239 static int grvga_pan_display(struct fb_var_screeninfo *var,
240 struct fb_info *info)
241 {
242 struct grvga_par *par = info->par;
243 struct fb_fix_screeninfo *fix = &info->fix;
244 u32 base_addr;
245
246 if (var->xoffset != 0)
247 return -EINVAL;
248
249 base_addr = fix->smem_start + (var->yoffset * fix->line_length);
250 base_addr &= ~3UL;
251
252 /* Set framebuffer base address */
253 __raw_writel(base_addr,
254 &par->regs->fb_pos);
255
256 return 0;
257 }
258
259 static struct fb_ops grvga_ops = {
260 .owner = THIS_MODULE,
261 .fb_check_var = grvga_check_var,
262 .fb_set_par = grvga_set_par,
263 .fb_setcolreg = grvga_setcolreg,
264 .fb_pan_display = grvga_pan_display,
265 .fb_fillrect = cfb_fillrect,
266 .fb_copyarea = cfb_copyarea,
267 .fb_imageblit = cfb_imageblit
268 };
269
grvga_parse_custom(char * options,struct fb_var_screeninfo * screendata)270 static int grvga_parse_custom(char *options,
271 struct fb_var_screeninfo *screendata)
272 {
273 char *this_opt;
274 int count = 0;
275 if (!options || !*options)
276 return -1;
277
278 while ((this_opt = strsep(&options, " ")) != NULL) {
279 if (!*this_opt)
280 continue;
281
282 switch (count) {
283 case 0:
284 screendata->pixclock = simple_strtoul(this_opt, NULL, 0);
285 count++;
286 break;
287 case 1:
288 screendata->xres = screendata->xres_virtual = simple_strtoul(this_opt, NULL, 0);
289 count++;
290 break;
291 case 2:
292 screendata->right_margin = simple_strtoul(this_opt, NULL, 0);
293 count++;
294 break;
295 case 3:
296 screendata->hsync_len = simple_strtoul(this_opt, NULL, 0);
297 count++;
298 break;
299 case 4:
300 screendata->left_margin = simple_strtoul(this_opt, NULL, 0);
301 count++;
302 break;
303 case 5:
304 screendata->yres = screendata->yres_virtual = simple_strtoul(this_opt, NULL, 0);
305 count++;
306 break;
307 case 6:
308 screendata->lower_margin = simple_strtoul(this_opt, NULL, 0);
309 count++;
310 break;
311 case 7:
312 screendata->vsync_len = simple_strtoul(this_opt, NULL, 0);
313 count++;
314 break;
315 case 8:
316 screendata->upper_margin = simple_strtoul(this_opt, NULL, 0);
317 count++;
318 break;
319 case 9:
320 screendata->bits_per_pixel = simple_strtoul(this_opt, NULL, 0);
321 count++;
322 break;
323 default:
324 return -1;
325 }
326 }
327 screendata->activate = FB_ACTIVATE_NOW;
328 screendata->vmode = FB_VMODE_NONINTERLACED;
329 return 0;
330 }
331
grvga_probe(struct platform_device * dev)332 static int grvga_probe(struct platform_device *dev)
333 {
334 struct fb_info *info;
335 int retval = -ENOMEM;
336 unsigned long virtual_start;
337 unsigned long grvga_fix_addr = 0;
338 unsigned long physical_start = 0;
339 unsigned long grvga_mem_size = 0;
340 struct grvga_par *par = NULL;
341 char *options = NULL, *mode_opt = NULL;
342
343 info = framebuffer_alloc(sizeof(struct grvga_par), &dev->dev);
344 if (!info) {
345 dev_err(&dev->dev, "framebuffer_alloc failed\n");
346 return -ENOMEM;
347 }
348
349 /* Expecting: "grvga: modestring, [addr:<framebuffer physical address>], [size:<framebuffer size>]
350 *
351 * If modestring is custom:<custom mode string> we parse the string which then contains all videoparameters
352 * If address is left out, we allocate memory,
353 * if size is left out we only allocate enough to support the given mode.
354 */
355 if (fb_get_options("grvga", &options)) {
356 retval = -ENODEV;
357 goto free_fb;
358 }
359
360 if (!options || !*options)
361 options = "640x480-8@60";
362
363 while (1) {
364 char *this_opt = strsep(&options, ",");
365
366 if (!this_opt)
367 break;
368
369 if (!strncmp(this_opt, "custom", 6)) {
370 if (grvga_parse_custom(this_opt, &info->var) < 0) {
371 dev_err(&dev->dev, "Failed to parse custom mode (%s).\n", this_opt);
372 retval = -EINVAL;
373 goto free_fb;
374 }
375 } else if (!strncmp(this_opt, "addr", 4))
376 grvga_fix_addr = simple_strtoul(this_opt + 5, NULL, 16);
377 else if (!strncmp(this_opt, "size", 4))
378 grvga_mem_size = simple_strtoul(this_opt + 5, NULL, 0);
379 else
380 mode_opt = this_opt;
381 }
382
383 par = info->par;
384 info->fbops = &grvga_ops;
385 info->fix = grvga_fix;
386 info->pseudo_palette = par->color_palette;
387 info->flags = FBINFO_DEFAULT | FBINFO_PARTIAL_PAN_OK | FBINFO_HWACCEL_YPAN;
388 info->fix.smem_len = grvga_mem_size;
389
390 if (!devm_request_mem_region(&dev->dev, dev->resource[0].start,
391 resource_size(&dev->resource[0]), "grlib-svgactrl regs")) {
392 dev_err(&dev->dev, "registers already mapped\n");
393 retval = -EBUSY;
394 goto free_fb;
395 }
396
397 par->regs = of_ioremap(&dev->resource[0], 0,
398 resource_size(&dev->resource[0]),
399 "grlib-svgactrl regs");
400
401 if (!par->regs) {
402 dev_err(&dev->dev, "failed to map registers\n");
403 retval = -ENOMEM;
404 goto free_fb;
405 }
406
407 retval = fb_alloc_cmap(&info->cmap, 256, 0);
408 if (retval < 0) {
409 dev_err(&dev->dev, "failed to allocate mem with fb_alloc_cmap\n");
410 retval = -ENOMEM;
411 goto unmap_regs;
412 }
413
414 if (mode_opt) {
415 retval = fb_find_mode(&info->var, info, mode_opt,
416 grvga_modedb, sizeof(grvga_modedb), &grvga_modedb[0], 8);
417 if (!retval || retval == 4) {
418 retval = -EINVAL;
419 goto dealloc_cmap;
420 }
421 }
422
423 if (!grvga_mem_size)
424 grvga_mem_size = info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel/8;
425
426 if (grvga_fix_addr) {
427 /* Got framebuffer base address from argument list */
428
429 physical_start = grvga_fix_addr;
430
431 if (!devm_request_mem_region(&dev->dev, physical_start,
432 grvga_mem_size, dev->name)) {
433 dev_err(&dev->dev, "failed to request memory region\n");
434 retval = -ENOMEM;
435 goto dealloc_cmap;
436 }
437
438 virtual_start = (unsigned long) ioremap(physical_start, grvga_mem_size);
439
440 if (!virtual_start) {
441 dev_err(&dev->dev, "error mapping framebuffer memory\n");
442 retval = -ENOMEM;
443 goto dealloc_cmap;
444 }
445 } else { /* Allocate frambuffer memory */
446
447 unsigned long page;
448
449 virtual_start = (unsigned long) __get_free_pages(GFP_DMA,
450 get_order(grvga_mem_size));
451 if (!virtual_start) {
452 dev_err(&dev->dev,
453 "unable to allocate framebuffer memory (%lu bytes)\n",
454 grvga_mem_size);
455 retval = -ENOMEM;
456 goto dealloc_cmap;
457 }
458
459 physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE);
460
461 /* Set page reserved so that mmap will work. This is necessary
462 * since we'll be remapping normal memory.
463 */
464 for (page = virtual_start;
465 page < PAGE_ALIGN(virtual_start + grvga_mem_size);
466 page += PAGE_SIZE) {
467 SetPageReserved(virt_to_page(page));
468 }
469
470 par->fb_alloced = 1;
471 }
472
473 memset((unsigned long *) virtual_start, 0, grvga_mem_size);
474
475 info->screen_base = (char __iomem *) virtual_start;
476 info->fix.smem_start = physical_start;
477 info->fix.smem_len = grvga_mem_size;
478
479 dev_set_drvdata(&dev->dev, info);
480
481 dev_info(&dev->dev,
482 "Aeroflex Gaisler framebuffer device (fb%d), %dx%d-%d, using %luK of video memory @ %p\n",
483 info->node, info->var.xres, info->var.yres, info->var.bits_per_pixel,
484 grvga_mem_size >> 10, info->screen_base);
485
486 retval = register_framebuffer(info);
487 if (retval < 0) {
488 dev_err(&dev->dev, "failed to register framebuffer\n");
489 goto free_mem;
490 }
491
492 __raw_writel(physical_start, &par->regs->fb_pos);
493 __raw_writel(__raw_readl(&par->regs->status) | 1, /* Enable framebuffer */
494 &par->regs->status);
495
496 return 0;
497
498 free_mem:
499 if (grvga_fix_addr)
500 iounmap((void *)virtual_start);
501 else
502 kfree((void *)virtual_start);
503 dealloc_cmap:
504 fb_dealloc_cmap(&info->cmap);
505 unmap_regs:
506 of_iounmap(&dev->resource[0], par->regs,
507 resource_size(&dev->resource[0]));
508 free_fb:
509 framebuffer_release(info);
510
511 return retval;
512 }
513
grvga_remove(struct platform_device * device)514 static int grvga_remove(struct platform_device *device)
515 {
516 struct fb_info *info = dev_get_drvdata(&device->dev);
517 struct grvga_par *par;
518
519 if (info) {
520 par = info->par;
521 unregister_framebuffer(info);
522 fb_dealloc_cmap(&info->cmap);
523
524 of_iounmap(&device->resource[0], par->regs,
525 resource_size(&device->resource[0]));
526
527 if (!par->fb_alloced)
528 iounmap(info->screen_base);
529 else
530 kfree((void *)info->screen_base);
531
532 framebuffer_release(info);
533 }
534
535 return 0;
536 }
537
538 static struct of_device_id svgactrl_of_match[] = {
539 {
540 .name = "GAISLER_SVGACTRL",
541 },
542 {
543 .name = "01_063",
544 },
545 {},
546 };
547 MODULE_DEVICE_TABLE(of, svgactrl_of_match);
548
549 static struct platform_driver grvga_driver = {
550 .driver = {
551 .name = "grlib-svgactrl",
552 .of_match_table = svgactrl_of_match,
553 },
554 .probe = grvga_probe,
555 .remove = grvga_remove,
556 };
557
558 module_platform_driver(grvga_driver);
559
560 MODULE_LICENSE("GPL");
561 MODULE_AUTHOR("Aeroflex Gaisler");
562 MODULE_DESCRIPTION("Aeroflex Gaisler framebuffer device driver");
563