1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Driver for Aeroflex Gaisler SVGACTRL framebuffer device. |
4 | * |
5 | * 2011 (c) Aeroflex Gaisler AB |
6 | * |
7 | * Full documentation of the core can be found here: |
8 | * https://www.gaisler.com/products/grlib/grip.pdf |
9 | * |
10 | * Contributors: Kristoffer Glembo <kristoffer@gaisler.com> |
11 | */ |
12 | |
13 | #include <linux/platform_device.h> |
14 | #include <linux/dma-mapping.h> |
15 | #include <linux/of.h> |
16 | #include <linux/module.h> |
17 | #include <linux/kernel.h> |
18 | #include <linux/string.h> |
19 | #include <linux/delay.h> |
20 | #include <linux/errno.h> |
21 | #include <linux/init.h> |
22 | #include <linux/slab.h> |
23 | #include <linux/tty.h> |
24 | #include <linux/mm.h> |
25 | #include <linux/fb.h> |
26 | #include <linux/io.h> |
27 | |
28 | struct grvga_regs { |
29 | u32 status; /* 0x00 */ |
30 | u32 video_length; /* 0x04 */ |
31 | u32 front_porch; /* 0x08 */ |
32 | u32 sync_length; /* 0x0C */ |
33 | u32 line_length; /* 0x10 */ |
34 | u32 fb_pos; /* 0x14 */ |
35 | u32 clk_vector[4]; /* 0x18 */ |
36 | u32 clut; /* 0x20 */ |
37 | }; |
38 | |
39 | struct grvga_par { |
40 | struct grvga_regs *regs; |
41 | u32 color_palette[16]; /* 16 entry pseudo palette used by fbcon in true color mode */ |
42 | int clk_sel; |
43 | int fb_alloced; /* = 1 if framebuffer is allocated in main memory */ |
44 | }; |
45 | |
46 | |
47 | static const struct fb_videomode grvga_modedb[] = { |
48 | { |
49 | /* 640x480 @ 60 Hz */ |
50 | NULL, 60, 640, 480, 40000, 48, 16, 39, 11, 96, 2, |
51 | 0, FB_VMODE_NONINTERLACED |
52 | }, { |
53 | /* 800x600 @ 60 Hz */ |
54 | NULL, 60, 800, 600, 25000, 88, 40, 23, 1, 128, 4, |
55 | 0, FB_VMODE_NONINTERLACED |
56 | }, { |
57 | /* 800x600 @ 72 Hz */ |
58 | NULL, 72, 800, 600, 20000, 64, 56, 23, 37, 120, 6, |
59 | 0, FB_VMODE_NONINTERLACED |
60 | }, { |
61 | /* 1024x768 @ 60 Hz */ |
62 | NULL, 60, 1024, 768, 15385, 160, 24, 29, 3, 136, 6, |
63 | 0, FB_VMODE_NONINTERLACED |
64 | } |
65 | }; |
66 | |
67 | static const struct fb_fix_screeninfo grvga_fix = { |
68 | .id = "AG SVGACTRL" , |
69 | .type = FB_TYPE_PACKED_PIXELS, |
70 | .visual = FB_VISUAL_PSEUDOCOLOR, |
71 | .xpanstep = 0, |
72 | .ypanstep = 1, |
73 | .ywrapstep = 0, |
74 | .accel = FB_ACCEL_NONE, |
75 | }; |
76 | |
77 | static int grvga_check_var(struct fb_var_screeninfo *var, |
78 | struct fb_info *info) |
79 | { |
80 | struct grvga_par *par = info->par; |
81 | int i; |
82 | |
83 | if (!var->xres) |
84 | var->xres = 1; |
85 | if (!var->yres) |
86 | var->yres = 1; |
87 | if (var->bits_per_pixel <= 8) |
88 | var->bits_per_pixel = 8; |
89 | else if (var->bits_per_pixel <= 16) |
90 | var->bits_per_pixel = 16; |
91 | else if (var->bits_per_pixel <= 24) |
92 | var->bits_per_pixel = 24; |
93 | else if (var->bits_per_pixel <= 32) |
94 | var->bits_per_pixel = 32; |
95 | else |
96 | return -EINVAL; |
97 | |
98 | var->xres_virtual = var->xres; |
99 | var->yres_virtual = 2*var->yres; |
100 | |
101 | if (info->fix.smem_len) { |
102 | if ((var->yres_virtual*var->xres_virtual*var->bits_per_pixel/8) > info->fix.smem_len) |
103 | return -ENOMEM; |
104 | } |
105 | |
106 | /* Which clocks that are available can be read out in these registers */ |
107 | for (i = 0; i <= 3 ; i++) { |
108 | if (var->pixclock == par->regs->clk_vector[i]) |
109 | break; |
110 | } |
111 | if (i <= 3) |
112 | par->clk_sel = i; |
113 | else |
114 | return -EINVAL; |
115 | |
116 | switch (info->var.bits_per_pixel) { |
117 | case 8: |
118 | var->red = (struct fb_bitfield) {0, 8, 0}; /* offset, length, msb-right */ |
119 | var->green = (struct fb_bitfield) {0, 8, 0}; |
120 | var->blue = (struct fb_bitfield) {0, 8, 0}; |
121 | var->transp = (struct fb_bitfield) {0, 0, 0}; |
122 | break; |
123 | case 16: |
124 | var->red = (struct fb_bitfield) {11, 5, 0}; |
125 | var->green = (struct fb_bitfield) {5, 6, 0}; |
126 | var->blue = (struct fb_bitfield) {0, 5, 0}; |
127 | var->transp = (struct fb_bitfield) {0, 0, 0}; |
128 | break; |
129 | case 24: |
130 | case 32: |
131 | var->red = (struct fb_bitfield) {16, 8, 0}; |
132 | var->green = (struct fb_bitfield) {8, 8, 0}; |
133 | var->blue = (struct fb_bitfield) {0, 8, 0}; |
134 | var->transp = (struct fb_bitfield) {24, 8, 0}; |
135 | break; |
136 | default: |
137 | return -EINVAL; |
138 | } |
139 | |
140 | return 0; |
141 | } |
142 | |
143 | static int grvga_set_par(struct fb_info *info) |
144 | { |
145 | |
146 | u32 func = 0; |
147 | struct grvga_par *par = info->par; |
148 | |
149 | __raw_writel(val: ((info->var.yres - 1) << 16) | (info->var.xres - 1), |
150 | addr: &par->regs->video_length); |
151 | |
152 | __raw_writel(val: (info->var.lower_margin << 16) | (info->var.right_margin), |
153 | addr: &par->regs->front_porch); |
154 | |
155 | __raw_writel(val: (info->var.vsync_len << 16) | (info->var.hsync_len), |
156 | addr: &par->regs->sync_length); |
157 | |
158 | __raw_writel(val: ((info->var.yres + info->var.lower_margin + info->var.upper_margin + info->var.vsync_len - 1) << 16) | |
159 | (info->var.xres + info->var.right_margin + info->var.left_margin + info->var.hsync_len - 1), |
160 | addr: &par->regs->line_length); |
161 | |
162 | switch (info->var.bits_per_pixel) { |
163 | case 8: |
164 | info->fix.visual = FB_VISUAL_PSEUDOCOLOR; |
165 | func = 1; |
166 | break; |
167 | case 16: |
168 | info->fix.visual = FB_VISUAL_TRUECOLOR; |
169 | func = 2; |
170 | break; |
171 | case 24: |
172 | case 32: |
173 | info->fix.visual = FB_VISUAL_TRUECOLOR; |
174 | func = 3; |
175 | break; |
176 | default: |
177 | return -EINVAL; |
178 | } |
179 | |
180 | __raw_writel(val: (par->clk_sel << 6) | (func << 4) | 1, |
181 | addr: &par->regs->status); |
182 | |
183 | info->fix.line_length = (info->var.xres_virtual*info->var.bits_per_pixel)/8; |
184 | return 0; |
185 | } |
186 | |
187 | static int grvga_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue, unsigned transp, struct fb_info *info) |
188 | { |
189 | struct grvga_par *par; |
190 | par = info->par; |
191 | |
192 | if (regno >= 256) /* Size of CLUT */ |
193 | return -EINVAL; |
194 | |
195 | if (info->var.grayscale) { |
196 | /* grayscale = 0.30*R + 0.59*G + 0.11*B */ |
197 | red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8; |
198 | } |
199 | |
200 | |
201 | |
202 | #define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16) |
203 | |
204 | red = CNVT_TOHW(red, info->var.red.length); |
205 | green = CNVT_TOHW(green, info->var.green.length); |
206 | blue = CNVT_TOHW(blue, info->var.blue.length); |
207 | transp = CNVT_TOHW(transp, info->var.transp.length); |
208 | |
209 | #undef CNVT_TOHW |
210 | |
211 | /* In PSEUDOCOLOR we use the hardware CLUT */ |
212 | if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR) |
213 | __raw_writel(val: (regno << 24) | (red << 16) | (green << 8) | blue, |
214 | addr: &par->regs->clut); |
215 | |
216 | /* Truecolor uses the pseudo palette */ |
217 | else if (info->fix.visual == FB_VISUAL_TRUECOLOR) { |
218 | u32 v; |
219 | if (regno >= 16) |
220 | return -EINVAL; |
221 | |
222 | |
223 | v = (red << info->var.red.offset) | |
224 | (green << info->var.green.offset) | |
225 | (blue << info->var.blue.offset) | |
226 | (transp << info->var.transp.offset); |
227 | |
228 | ((u32 *) (info->pseudo_palette))[regno] = v; |
229 | } |
230 | return 0; |
231 | } |
232 | |
233 | static int grvga_pan_display(struct fb_var_screeninfo *var, |
234 | struct fb_info *info) |
235 | { |
236 | struct grvga_par *par = info->par; |
237 | struct fb_fix_screeninfo *fix = &info->fix; |
238 | u32 base_addr; |
239 | |
240 | if (var->xoffset != 0) |
241 | return -EINVAL; |
242 | |
243 | base_addr = fix->smem_start + (var->yoffset * fix->line_length); |
244 | base_addr &= ~3UL; |
245 | |
246 | /* Set framebuffer base address */ |
247 | __raw_writel(val: base_addr, |
248 | addr: &par->regs->fb_pos); |
249 | |
250 | return 0; |
251 | } |
252 | |
253 | static const struct fb_ops grvga_ops = { |
254 | .owner = THIS_MODULE, |
255 | FB_DEFAULT_IOMEM_OPS, |
256 | .fb_check_var = grvga_check_var, |
257 | .fb_set_par = grvga_set_par, |
258 | .fb_setcolreg = grvga_setcolreg, |
259 | .fb_pan_display = grvga_pan_display, |
260 | }; |
261 | |
262 | static int grvga_parse_custom(char *options, |
263 | struct fb_var_screeninfo *screendata) |
264 | { |
265 | char *this_opt; |
266 | int count = 0; |
267 | if (!options || !*options) |
268 | return -1; |
269 | |
270 | while ((this_opt = strsep(&options, " " )) != NULL) { |
271 | if (!*this_opt) |
272 | continue; |
273 | |
274 | switch (count) { |
275 | case 0: |
276 | screendata->pixclock = simple_strtoul(this_opt, NULL, 0); |
277 | count++; |
278 | break; |
279 | case 1: |
280 | screendata->xres = screendata->xres_virtual = simple_strtoul(this_opt, NULL, 0); |
281 | count++; |
282 | break; |
283 | case 2: |
284 | screendata->right_margin = simple_strtoul(this_opt, NULL, 0); |
285 | count++; |
286 | break; |
287 | case 3: |
288 | screendata->hsync_len = simple_strtoul(this_opt, NULL, 0); |
289 | count++; |
290 | break; |
291 | case 4: |
292 | screendata->left_margin = simple_strtoul(this_opt, NULL, 0); |
293 | count++; |
294 | break; |
295 | case 5: |
296 | screendata->yres = screendata->yres_virtual = simple_strtoul(this_opt, NULL, 0); |
297 | count++; |
298 | break; |
299 | case 6: |
300 | screendata->lower_margin = simple_strtoul(this_opt, NULL, 0); |
301 | count++; |
302 | break; |
303 | case 7: |
304 | screendata->vsync_len = simple_strtoul(this_opt, NULL, 0); |
305 | count++; |
306 | break; |
307 | case 8: |
308 | screendata->upper_margin = simple_strtoul(this_opt, NULL, 0); |
309 | count++; |
310 | break; |
311 | case 9: |
312 | screendata->bits_per_pixel = simple_strtoul(this_opt, NULL, 0); |
313 | count++; |
314 | break; |
315 | default: |
316 | return -1; |
317 | } |
318 | } |
319 | screendata->activate = FB_ACTIVATE_NOW; |
320 | screendata->vmode = FB_VMODE_NONINTERLACED; |
321 | return 0; |
322 | } |
323 | |
324 | static int grvga_probe(struct platform_device *dev) |
325 | { |
326 | struct fb_info *info; |
327 | int retval = -ENOMEM; |
328 | unsigned long virtual_start; |
329 | unsigned long grvga_fix_addr = 0; |
330 | unsigned long physical_start = 0; |
331 | unsigned long grvga_mem_size = 0; |
332 | struct grvga_par *par = NULL; |
333 | char *options = NULL, *mode_opt = NULL; |
334 | |
335 | info = framebuffer_alloc(size: sizeof(struct grvga_par), dev: &dev->dev); |
336 | if (!info) |
337 | return -ENOMEM; |
338 | |
339 | /* Expecting: "grvga: modestring, [addr:<framebuffer physical address>], [size:<framebuffer size>] |
340 | * |
341 | * If modestring is custom:<custom mode string> we parse the string which then contains all videoparameters |
342 | * If address is left out, we allocate memory, |
343 | * if size is left out we only allocate enough to support the given mode. |
344 | */ |
345 | if (fb_get_options(name: "grvga" , option: &options)) { |
346 | retval = -ENODEV; |
347 | goto free_fb; |
348 | } |
349 | |
350 | if (!options || !*options) |
351 | options = "640x480-8@60" ; |
352 | |
353 | while (1) { |
354 | char *this_opt = strsep(&options, "," ); |
355 | |
356 | if (!this_opt) |
357 | break; |
358 | |
359 | if (!strncmp(this_opt, "custom" , 6)) { |
360 | if (grvga_parse_custom(options: this_opt, screendata: &info->var) < 0) { |
361 | dev_err(&dev->dev, "Failed to parse custom mode (%s).\n" , this_opt); |
362 | retval = -EINVAL; |
363 | goto free_fb; |
364 | } |
365 | } else if (!strncmp(this_opt, "addr" , 4)) |
366 | grvga_fix_addr = simple_strtoul(this_opt + 5, NULL, 16); |
367 | else if (!strncmp(this_opt, "size" , 4)) |
368 | grvga_mem_size = simple_strtoul(this_opt + 5, NULL, 0); |
369 | else |
370 | mode_opt = this_opt; |
371 | } |
372 | |
373 | par = info->par; |
374 | info->fbops = &grvga_ops; |
375 | info->fix = grvga_fix; |
376 | info->pseudo_palette = par->color_palette; |
377 | info->flags = FBINFO_PARTIAL_PAN_OK | FBINFO_HWACCEL_YPAN; |
378 | info->fix.smem_len = grvga_mem_size; |
379 | |
380 | if (!devm_request_mem_region(&dev->dev, dev->resource[0].start, |
381 | resource_size(&dev->resource[0]), "grlib-svgactrl regs" )) { |
382 | dev_err(&dev->dev, "registers already mapped\n" ); |
383 | retval = -EBUSY; |
384 | goto free_fb; |
385 | } |
386 | |
387 | par->regs = of_ioremap(&dev->resource[0], 0, |
388 | resource_size(res: &dev->resource[0]), |
389 | "grlib-svgactrl regs" ); |
390 | |
391 | if (!par->regs) { |
392 | dev_err(&dev->dev, "failed to map registers\n" ); |
393 | retval = -ENOMEM; |
394 | goto free_fb; |
395 | } |
396 | |
397 | retval = fb_alloc_cmap(cmap: &info->cmap, len: 256, transp: 0); |
398 | if (retval < 0) { |
399 | dev_err(&dev->dev, "failed to allocate mem with fb_alloc_cmap\n" ); |
400 | retval = -ENOMEM; |
401 | goto unmap_regs; |
402 | } |
403 | |
404 | if (mode_opt) { |
405 | retval = fb_find_mode(var: &info->var, info, mode_option: mode_opt, |
406 | db: grvga_modedb, dbsize: sizeof(grvga_modedb), default_mode: &grvga_modedb[0], default_bpp: 8); |
407 | if (!retval || retval == 4) { |
408 | retval = -EINVAL; |
409 | goto dealloc_cmap; |
410 | } |
411 | } |
412 | |
413 | if (!grvga_mem_size) |
414 | grvga_mem_size = info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel/8; |
415 | |
416 | if (grvga_fix_addr) { |
417 | /* Got framebuffer base address from argument list */ |
418 | |
419 | physical_start = grvga_fix_addr; |
420 | |
421 | if (!devm_request_mem_region(&dev->dev, physical_start, |
422 | grvga_mem_size, dev->name)) { |
423 | dev_err(&dev->dev, "failed to request memory region\n" ); |
424 | retval = -ENOMEM; |
425 | goto dealloc_cmap; |
426 | } |
427 | |
428 | virtual_start = (unsigned long) ioremap(offset: physical_start, size: grvga_mem_size); |
429 | |
430 | if (!virtual_start) { |
431 | dev_err(&dev->dev, "error mapping framebuffer memory\n" ); |
432 | retval = -ENOMEM; |
433 | goto dealloc_cmap; |
434 | } |
435 | } else { /* Allocate frambuffer memory */ |
436 | |
437 | unsigned long page; |
438 | |
439 | virtual_start = (unsigned long) __get_free_pages(GFP_DMA, |
440 | order: get_order(size: grvga_mem_size)); |
441 | if (!virtual_start) { |
442 | dev_err(&dev->dev, |
443 | "unable to allocate framebuffer memory (%lu bytes)\n" , |
444 | grvga_mem_size); |
445 | retval = -ENOMEM; |
446 | goto dealloc_cmap; |
447 | } |
448 | |
449 | physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE); |
450 | |
451 | /* Set page reserved so that mmap will work. This is necessary |
452 | * since we'll be remapping normal memory. |
453 | */ |
454 | for (page = virtual_start; |
455 | page < PAGE_ALIGN(virtual_start + grvga_mem_size); |
456 | page += PAGE_SIZE) { |
457 | SetPageReserved(virt_to_page(page)); |
458 | } |
459 | |
460 | par->fb_alloced = 1; |
461 | } |
462 | |
463 | memset((unsigned long *) virtual_start, 0, grvga_mem_size); |
464 | |
465 | info->screen_base = (char __iomem *) virtual_start; |
466 | info->fix.smem_start = physical_start; |
467 | info->fix.smem_len = grvga_mem_size; |
468 | |
469 | dev_set_drvdata(dev: &dev->dev, data: info); |
470 | |
471 | dev_info(&dev->dev, |
472 | "Aeroflex Gaisler framebuffer device (fb%d), %dx%d-%d, using %luK of video memory @ %p\n" , |
473 | info->node, info->var.xres, info->var.yres, info->var.bits_per_pixel, |
474 | grvga_mem_size >> 10, info->screen_base); |
475 | |
476 | retval = register_framebuffer(fb_info: info); |
477 | if (retval < 0) { |
478 | dev_err(&dev->dev, "failed to register framebuffer\n" ); |
479 | goto free_mem; |
480 | } |
481 | |
482 | __raw_writel(val: physical_start, addr: &par->regs->fb_pos); |
483 | __raw_writel(__raw_readl(addr: &par->regs->status) | 1, /* Enable framebuffer */ |
484 | addr: &par->regs->status); |
485 | |
486 | return 0; |
487 | |
488 | free_mem: |
489 | if (grvga_fix_addr) |
490 | iounmap(addr: (void *)virtual_start); |
491 | else |
492 | kfree(objp: (void *)virtual_start); |
493 | dealloc_cmap: |
494 | fb_dealloc_cmap(cmap: &info->cmap); |
495 | unmap_regs: |
496 | of_iounmap(&dev->resource[0], par->regs, |
497 | resource_size(res: &dev->resource[0])); |
498 | free_fb: |
499 | framebuffer_release(info); |
500 | |
501 | return retval; |
502 | } |
503 | |
504 | static void grvga_remove(struct platform_device *device) |
505 | { |
506 | struct fb_info *info = dev_get_drvdata(dev: &device->dev); |
507 | struct grvga_par *par; |
508 | |
509 | if (info) { |
510 | par = info->par; |
511 | unregister_framebuffer(fb_info: info); |
512 | fb_dealloc_cmap(cmap: &info->cmap); |
513 | |
514 | of_iounmap(&device->resource[0], par->regs, |
515 | resource_size(res: &device->resource[0])); |
516 | |
517 | if (!par->fb_alloced) |
518 | iounmap(addr: info->screen_base); |
519 | else |
520 | kfree(objp: (void *)info->screen_base); |
521 | |
522 | framebuffer_release(info); |
523 | } |
524 | } |
525 | |
526 | static struct of_device_id svgactrl_of_match[] = { |
527 | { |
528 | .name = "GAISLER_SVGACTRL" , |
529 | }, |
530 | { |
531 | .name = "01_063" , |
532 | }, |
533 | {}, |
534 | }; |
535 | MODULE_DEVICE_TABLE(of, svgactrl_of_match); |
536 | |
537 | static struct platform_driver grvga_driver = { |
538 | .driver = { |
539 | .name = "grlib-svgactrl" , |
540 | .of_match_table = svgactrl_of_match, |
541 | }, |
542 | .probe = grvga_probe, |
543 | .remove_new = grvga_remove, |
544 | }; |
545 | |
546 | module_platform_driver(grvga_driver); |
547 | |
548 | MODULE_LICENSE("GPL" ); |
549 | MODULE_AUTHOR("Aeroflex Gaisler" ); |
550 | MODULE_DESCRIPTION("Aeroflex Gaisler framebuffer device driver" ); |
551 | |