drivers/video/fbdev/grvga.c

   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 const 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
  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
 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
 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
 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
 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
 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
 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");