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