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_DEFAULT_IOMEM_OPS, 257 .fb_check_var = grvga_check_var, 258 .fb_set_par = grvga_set_par, 259 .fb_setcolreg = grvga_setcolreg, 260 .fb_pan_display = grvga_pan_display, 261 }; 262 263 static int grvga_parse_custom(char *options, 264 struct fb_var_screeninfo *screendata) 265 { 266 char *this_opt; 267 int count = 0; 268 if (!options || !*options) 269 return -1; 270 271 while ((this_opt = strsep(&options, " ")) != NULL) { 272 if (!*this_opt) 273 continue; 274 275 switch (count) { 276 case 0: 277 screendata->pixclock = simple_strtoul(this_opt, NULL, 0); 278 count++; 279 break; 280 case 1: 281 screendata->xres = screendata->xres_virtual = simple_strtoul(this_opt, NULL, 0); 282 count++; 283 break; 284 case 2: 285 screendata->right_margin = simple_strtoul(this_opt, NULL, 0); 286 count++; 287 break; 288 case 3: 289 screendata->hsync_len = simple_strtoul(this_opt, NULL, 0); 290 count++; 291 break; 292 case 4: 293 screendata->left_margin = simple_strtoul(this_opt, NULL, 0); 294 count++; 295 break; 296 case 5: 297 screendata->yres = screendata->yres_virtual = simple_strtoul(this_opt, NULL, 0); 298 count++; 299 break; 300 case 6: 301 screendata->lower_margin = simple_strtoul(this_opt, NULL, 0); 302 count++; 303 break; 304 case 7: 305 screendata->vsync_len = simple_strtoul(this_opt, NULL, 0); 306 count++; 307 break; 308 case 8: 309 screendata->upper_margin = simple_strtoul(this_opt, NULL, 0); 310 count++; 311 break; 312 case 9: 313 screendata->bits_per_pixel = simple_strtoul(this_opt, NULL, 0); 314 count++; 315 break; 316 default: 317 return -1; 318 } 319 } 320 screendata->activate = FB_ACTIVATE_NOW; 321 screendata->vmode = FB_VMODE_NONINTERLACED; 322 return 0; 323 } 324 325 static int grvga_probe(struct platform_device *dev) 326 { 327 struct fb_info *info; 328 int retval = -ENOMEM; 329 unsigned long virtual_start; 330 unsigned long grvga_fix_addr = 0; 331 unsigned long physical_start = 0; 332 unsigned long grvga_mem_size = 0; 333 struct grvga_par *par = NULL; 334 char *options = NULL, *mode_opt = NULL; 335 336 info = framebuffer_alloc(sizeof(struct grvga_par), &dev->dev); 337 if (!info) 338 return -ENOMEM; 339 340 /* Expecting: "grvga: modestring, [addr:<framebuffer physical address>], [size:<framebuffer size>] 341 * 342 * If modestring is custom:<custom mode string> we parse the string which then contains all videoparameters 343 * If address is left out, we allocate memory, 344 * if size is left out we only allocate enough to support the given mode. 345 */ 346 if (fb_get_options("grvga", &options)) { 347 retval = -ENODEV; 348 goto free_fb; 349 } 350 351 if (!options || !*options) 352 options = "640x480-8@60"; 353 354 while (1) { 355 char *this_opt = strsep(&options, ","); 356 357 if (!this_opt) 358 break; 359 360 if (!strncmp(this_opt, "custom", 6)) { 361 if (grvga_parse_custom(this_opt, &info->var) < 0) { 362 dev_err(&dev->dev, "Failed to parse custom mode (%s).\n", this_opt); 363 retval = -EINVAL; 364 goto free_fb; 365 } 366 } else if (!strncmp(this_opt, "addr", 4)) 367 grvga_fix_addr = simple_strtoul(this_opt + 5, NULL, 16); 368 else if (!strncmp(this_opt, "size", 4)) 369 grvga_mem_size = simple_strtoul(this_opt + 5, NULL, 0); 370 else 371 mode_opt = this_opt; 372 } 373 374 par = info->par; 375 info->fbops = &grvga_ops; 376 info->fix = grvga_fix; 377 info->pseudo_palette = par->color_palette; 378 info->flags = FBINFO_PARTIAL_PAN_OK | FBINFO_HWACCEL_YPAN; 379 info->fix.smem_len = grvga_mem_size; 380 381 if (!devm_request_mem_region(&dev->dev, dev->resource[0].start, 382 resource_size(&dev->resource[0]), "grlib-svgactrl regs")) { 383 dev_err(&dev->dev, "registers already mapped\n"); 384 retval = -EBUSY; 385 goto free_fb; 386 } 387 388 par->regs = of_ioremap(&dev->resource[0], 0, 389 resource_size(&dev->resource[0]), 390 "grlib-svgactrl regs"); 391 392 if (!par->regs) { 393 dev_err(&dev->dev, "failed to map registers\n"); 394 retval = -ENOMEM; 395 goto free_fb; 396 } 397 398 retval = fb_alloc_cmap(&info->cmap, 256, 0); 399 if (retval < 0) { 400 dev_err(&dev->dev, "failed to allocate mem with fb_alloc_cmap\n"); 401 retval = -ENOMEM; 402 goto unmap_regs; 403 } 404 405 if (mode_opt) { 406 retval = fb_find_mode(&info->var, info, mode_opt, 407 grvga_modedb, sizeof(grvga_modedb), &grvga_modedb[0], 8); 408 if (!retval || retval == 4) { 409 retval = -EINVAL; 410 goto dealloc_cmap; 411 } 412 } 413 414 if (!grvga_mem_size) 415 grvga_mem_size = info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel/8; 416 417 if (grvga_fix_addr) { 418 /* Got framebuffer base address from argument list */ 419 420 physical_start = grvga_fix_addr; 421 422 if (!devm_request_mem_region(&dev->dev, physical_start, 423 grvga_mem_size, dev->name)) { 424 dev_err(&dev->dev, "failed to request memory region\n"); 425 retval = -ENOMEM; 426 goto dealloc_cmap; 427 } 428 429 virtual_start = (unsigned long) ioremap(physical_start, grvga_mem_size); 430 431 if (!virtual_start) { 432 dev_err(&dev->dev, "error mapping framebuffer memory\n"); 433 retval = -ENOMEM; 434 goto dealloc_cmap; 435 } 436 } else { /* Allocate frambuffer memory */ 437 438 unsigned long page; 439 440 virtual_start = (unsigned long) __get_free_pages(GFP_DMA, 441 get_order(grvga_mem_size)); 442 if (!virtual_start) { 443 dev_err(&dev->dev, 444 "unable to allocate framebuffer memory (%lu bytes)\n", 445 grvga_mem_size); 446 retval = -ENOMEM; 447 goto dealloc_cmap; 448 } 449 450 physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE); 451 452 /* Set page reserved so that mmap will work. This is necessary 453 * since we'll be remapping normal memory. 454 */ 455 for (page = virtual_start; 456 page < PAGE_ALIGN(virtual_start + grvga_mem_size); 457 page += PAGE_SIZE) { 458 SetPageReserved(virt_to_page(page)); 459 } 460 461 par->fb_alloced = 1; 462 } 463 464 memset((unsigned long *) virtual_start, 0, grvga_mem_size); 465 466 info->screen_base = (char __iomem *) virtual_start; 467 info->fix.smem_start = physical_start; 468 info->fix.smem_len = grvga_mem_size; 469 470 dev_set_drvdata(&dev->dev, info); 471 472 dev_info(&dev->dev, 473 "Aeroflex Gaisler framebuffer device (fb%d), %dx%d-%d, using %luK of video memory @ %p\n", 474 info->node, info->var.xres, info->var.yres, info->var.bits_per_pixel, 475 grvga_mem_size >> 10, info->screen_base); 476 477 retval = register_framebuffer(info); 478 if (retval < 0) { 479 dev_err(&dev->dev, "failed to register framebuffer\n"); 480 goto free_mem; 481 } 482 483 __raw_writel(physical_start, &par->regs->fb_pos); 484 __raw_writel(__raw_readl(&par->regs->status) | 1, /* Enable framebuffer */ 485 &par->regs->status); 486 487 return 0; 488 489 free_mem: 490 if (grvga_fix_addr) 491 iounmap((void *)virtual_start); 492 else 493 kfree((void *)virtual_start); 494 dealloc_cmap: 495 fb_dealloc_cmap(&info->cmap); 496 unmap_regs: 497 of_iounmap(&dev->resource[0], par->regs, 498 resource_size(&dev->resource[0])); 499 free_fb: 500 framebuffer_release(info); 501 502 return retval; 503 } 504 505 static void grvga_remove(struct platform_device *device) 506 { 507 struct fb_info *info = dev_get_drvdata(&device->dev); 508 struct grvga_par *par; 509 510 if (info) { 511 par = info->par; 512 unregister_framebuffer(info); 513 fb_dealloc_cmap(&info->cmap); 514 515 of_iounmap(&device->resource[0], par->regs, 516 resource_size(&device->resource[0])); 517 518 if (!par->fb_alloced) 519 iounmap(info->screen_base); 520 else 521 kfree((void *)info->screen_base); 522 523 framebuffer_release(info); 524 } 525 } 526 527 static struct of_device_id svgactrl_of_match[] = { 528 { 529 .name = "GAISLER_SVGACTRL", 530 }, 531 { 532 .name = "01_063", 533 }, 534 {}, 535 }; 536 MODULE_DEVICE_TABLE(of, svgactrl_of_match); 537 538 static struct platform_driver grvga_driver = { 539 .driver = { 540 .name = "grlib-svgactrl", 541 .of_match_table = svgactrl_of_match, 542 }, 543 .probe = grvga_probe, 544 .remove_new = grvga_remove, 545 }; 546 547 module_platform_driver(grvga_driver); 548 549 MODULE_LICENSE("GPL"); 550 MODULE_AUTHOR("Aeroflex Gaisler"); 551 MODULE_DESCRIPTION("Aeroflex Gaisler framebuffer device driver"); 552