drivers/video/fbdev/efifb.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Framebuffer driver for EFI/UEFI based system
   4  *
   5  * (c) 2006 Edgar Hucek <gimli@dark-green.com>
   6  * Original efi driver written by Gerd Knorr <kraxel@goldbach.in-berlin.de>
   7  *
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/efi.h>
  12 #include <linux/errno.h>
  13 #include <linux/fb.h>
  14 #include <linux/pci.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/screen_info.h>
  17 #include <video/vga.h>
  18 #include <asm/efi.h>
  19 #include <drm/drm_utils.h> /* For drm_get_panel_orientation_quirk */
  20 #include <drm/drm_connector.h>  /* For DRM_MODE_PANEL_ORIENTATION_* */
  21
  22 static bool request_mem_succeeded = false;
  23 static bool nowc = false;
  24
  25 static struct fb_var_screeninfo efifb_defined = {
  26         .activate               = FB_ACTIVATE_NOW,
  27         .height                 = -1,
  28         .width                  = -1,
  29         .right_margin           = 32,
  30         .upper_margin           = 16,
  31         .lower_margin           = 4,
  32         .vsync_len              = 4,
  33         .vmode                  = FB_VMODE_NONINTERLACED,
  34 };
  35
  36 static struct fb_fix_screeninfo efifb_fix = {
  37         .id                     = "EFI VGA",
  38         .type                   = FB_TYPE_PACKED_PIXELS,
  39         .accel                  = FB_ACCEL_NONE,
  40         .visual                 = FB_VISUAL_TRUECOLOR,
  41 };
  42
  43 static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
  44                            unsigned blue, unsigned transp,
  45                            struct fb_info *info)
  46 {
  47         /*
  48          *  Set a single color register. The values supplied are
  49          *  already rounded down to the hardware's capabilities
  50          *  (according to the entries in the `var' structure). Return
  51          *  != 0 for invalid regno.
  52          */
  53
  54         if (regno >= info->cmap.len)
  55                 return 1;
  56
  57         if (regno < 16) {
  58                 red   >>= 16 - info->var.red.length;
  59                 green >>= 16 - info->var.green.length;
  60                 blue  >>= 16 - info->var.blue.length;
  61                 ((u32 *)(info->pseudo_palette))[regno] =
  62                         (red   << info->var.red.offset)   |
  63                         (green << info->var.green.offset) |
  64                         (blue  << info->var.blue.offset);
  65         }
  66         return 0;
  67 }
  68
  69 static void efifb_destroy(struct fb_info *info)
  70 {
  71         if (info->screen_base)
  72                 iounmap(info->screen_base);
  73         if (request_mem_succeeded)
  74                 release_mem_region(info->apertures->ranges[0].base,
  75                                    info->apertures->ranges[0].size);
  76         fb_dealloc_cmap(&info->cmap);
  77 }
  78
  79 static struct fb_ops efifb_ops = {
  80         .owner          = THIS_MODULE,
  81         .fb_destroy     = efifb_destroy,
  82         .fb_setcolreg   = efifb_setcolreg,
  83         .fb_fillrect    = cfb_fillrect,
  84         .fb_copyarea    = cfb_copyarea,
  85         .fb_imageblit   = cfb_imageblit,
  86 };
  87
  88 static int efifb_setup(char *options)
  89 {
  90         char *this_opt;
  91
  92         if (options && *options) {
  93                 while ((this_opt = strsep(&options, ",")) != NULL) {
  94                         if (!*this_opt) continue;
  95
  96                         efifb_setup_from_dmi(&screen_info, this_opt);
  97
  98                         if (!strncmp(this_opt, "base:", 5))
  99                                 screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
 100                         else if (!strncmp(this_opt, "stride:", 7))
 101                                 screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
 102                         else if (!strncmp(this_opt, "height:", 7))
 103                                 screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
 104                         else if (!strncmp(this_opt, "width:", 6))
 105                                 screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
 106                         else if (!strcmp(this_opt, "nowc"))
 107                                 nowc = true;
 108                 }
 109         }
 110
 111         return 0;
 112 }
 113
 114 static inline bool fb_base_is_valid(void)
 115 {
 116         if (screen_info.lfb_base)
 117                 return true;
 118
 119         if (!(screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE))
 120                 return false;
 121
 122         if (screen_info.ext_lfb_base)
 123                 return true;
 124
 125         return false;
 126 }
 127
 128 #define efifb_attr_decl(name, fmt)                                      \
 129 static ssize_t name##_show(struct device *dev,                          \
 130                            struct device_attribute *attr,               \
 131                            char *buf)                                   \
 132 {                                                                       \
 133         return sprintf(buf, fmt "\n", (screen_info.lfb_##name));        \
 134 }                                                                       \
 135 static DEVICE_ATTR_RO(name)
 136
 137 efifb_attr_decl(base, "0x%x");
 138 efifb_attr_decl(linelength, "%u");
 139 efifb_attr_decl(height, "%u");
 140 efifb_attr_decl(width, "%u");
 141 efifb_attr_decl(depth, "%u");
 142
 143 static struct attribute *efifb_attrs[] = {
 144         &dev_attr_base.attr,
 145         &dev_attr_linelength.attr,
 146         &dev_attr_width.attr,
 147         &dev_attr_height.attr,
 148         &dev_attr_depth.attr,
 149         NULL
 150 };
 151 ATTRIBUTE_GROUPS(efifb);
 152
 153 static bool pci_dev_disabled;   /* FB base matches BAR of a disabled device */
 154
 155 static struct pci_dev *efifb_pci_dev;   /* dev with BAR covering the efifb */
 156 static struct resource *bar_resource;
 157 static u64 bar_offset;
 158
 159 static int efifb_probe(struct platform_device *dev)
 160 {
 161         struct fb_info *info;
 162         int err, orientation;
 163         unsigned int size_vmode;
 164         unsigned int size_remap;
 165         unsigned int size_total;
 166         char *option = NULL;
 167
 168         if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI || pci_dev_disabled)
 169                 return -ENODEV;
 170
 171         if (fb_get_options("efifb", &option))
 172                 return -ENODEV;
 173         efifb_setup(option);
 174
 175         /* We don't get linelength from UGA Draw Protocol, only from
 176          * EFI Graphics Protocol.  So if it's not in DMI, and it's not
 177          * passed in from the user, we really can't use the framebuffer.
 178          */
 179         if (!screen_info.lfb_linelength)
 180                 return -ENODEV;
 181
 182         if (!screen_info.lfb_depth)
 183                 screen_info.lfb_depth = 32;
 184         if (!screen_info.pages)
 185                 screen_info.pages = 1;
 186         if (!fb_base_is_valid()) {
 187                 printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
 188                 return -ENODEV;
 189         }
 190         printk(KERN_INFO "efifb: probing for efifb\n");
 191
 192         /* just assume they're all unset if any are */
 193         if (!screen_info.blue_size) {
 194                 screen_info.blue_size = 8;
 195                 screen_info.blue_pos = 0;
 196                 screen_info.green_size = 8;
 197                 screen_info.green_pos = 8;
 198                 screen_info.red_size = 8;
 199                 screen_info.red_pos = 16;
 200                 screen_info.rsvd_size = 8;
 201                 screen_info.rsvd_pos = 24;
 202         }
 203
 204         efifb_fix.smem_start = screen_info.lfb_base;
 205
 206         if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) {
 207                 u64 ext_lfb_base;
 208
 209                 ext_lfb_base = (u64)(unsigned long)screen_info.ext_lfb_base << 32;
 210                 efifb_fix.smem_start |= ext_lfb_base;
 211         }
 212
 213         if (bar_resource &&
 214             bar_resource->start + bar_offset != efifb_fix.smem_start) {
 215                 dev_info(&efifb_pci_dev->dev,
 216                          "BAR has moved, updating efifb address\n");
 217                 efifb_fix.smem_start = bar_resource->start + bar_offset;
 218         }
 219
 220         efifb_defined.bits_per_pixel = screen_info.lfb_depth;
 221         efifb_defined.xres = screen_info.lfb_width;
 222         efifb_defined.yres = screen_info.lfb_height;
 223         efifb_fix.line_length = screen_info.lfb_linelength;
 224
 225         /*   size_vmode -- that is the amount of memory needed for the
 226          *                 used video mode, i.e. the minimum amount of
 227          *                 memory we need. */
 228         size_vmode = efifb_defined.yres * efifb_fix.line_length;
 229
 230         /*   size_total -- all video memory we have. Used for
 231          *                 entries, ressource allocation and bounds
 232          *                 checking. */
 233         size_total = screen_info.lfb_size;
 234         if (size_total < size_vmode)
 235                 size_total = size_vmode;
 236
 237         /*   size_remap -- the amount of video memory we are going to
 238          *                 use for efifb.  With modern cards it is no
 239          *                 option to simply use size_total as that
 240          *                 wastes plenty of kernel address space. */
 241         size_remap  = size_vmode * 2;
 242         if (size_remap > size_total)
 243                 size_remap = size_total;
 244         if (size_remap % PAGE_SIZE)
 245                 size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
 246         efifb_fix.smem_len = size_remap;
 247
 248         if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
 249                 request_mem_succeeded = true;
 250         } else {
 251                 /* We cannot make this fatal. Sometimes this comes from magic
 252                    spaces our resource handlers simply don't know about */
 253                 pr_warn("efifb: cannot reserve video memory at 0x%lx\n",
 254                         efifb_fix.smem_start);
 255         }
 256
 257         info = framebuffer_alloc(sizeof(u32) * 16, &dev->dev);
 258         if (!info) {
 259                 pr_err("efifb: cannot allocate framebuffer\n");
 260                 err = -ENOMEM;
 261                 goto err_release_mem;
 262         }
 263         platform_set_drvdata(dev, info);
 264         info->pseudo_palette = info->par;
 265         info->par = NULL;
 266
 267         info->apertures = alloc_apertures(1);
 268         if (!info->apertures) {
 269                 err = -ENOMEM;
 270                 goto err_release_fb;
 271         }
 272         info->apertures->ranges[0].base = efifb_fix.smem_start;
 273         info->apertures->ranges[0].size = size_remap;
 274
 275         if (nowc)
 276                 info->screen_base = ioremap(efifb_fix.smem_start, efifb_fix.smem_len);
 277         else
 278                 info->screen_base = ioremap_wc(efifb_fix.smem_start, efifb_fix.smem_len);
 279         if (!info->screen_base) {
 280                 pr_err("efifb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n",
 281                         efifb_fix.smem_len, efifb_fix.smem_start);
 282                 err = -EIO;
 283                 goto err_release_fb;
 284         }
 285
 286         pr_info("efifb: framebuffer at 0x%lx, using %dk, total %dk\n",
 287                efifb_fix.smem_start, size_remap/1024, size_total/1024);
 288         pr_info("efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
 289                efifb_defined.xres, efifb_defined.yres,
 290                efifb_defined.bits_per_pixel, efifb_fix.line_length,
 291                screen_info.pages);
 292
 293         efifb_defined.xres_virtual = efifb_defined.xres;
 294         efifb_defined.yres_virtual = efifb_fix.smem_len /
 295                                         efifb_fix.line_length;
 296         pr_info("efifb: scrolling: redraw\n");
 297         efifb_defined.yres_virtual = efifb_defined.yres;
 298
 299         /* some dummy values for timing to make fbset happy */
 300         efifb_defined.pixclock     = 10000000 / efifb_defined.xres *
 301                                         1000 / efifb_defined.yres;
 302         efifb_defined.left_margin  = (efifb_defined.xres / 8) & 0xf8;
 303         efifb_defined.hsync_len    = (efifb_defined.xres / 8) & 0xf8;
 304
 305         efifb_defined.red.offset    = screen_info.red_pos;
 306         efifb_defined.red.length    = screen_info.red_size;
 307         efifb_defined.green.offset  = screen_info.green_pos;
 308         efifb_defined.green.length  = screen_info.green_size;
 309         efifb_defined.blue.offset   = screen_info.blue_pos;
 310         efifb_defined.blue.length   = screen_info.blue_size;
 311         efifb_defined.transp.offset = screen_info.rsvd_pos;
 312         efifb_defined.transp.length = screen_info.rsvd_size;
 313
 314         pr_info("efifb: %s: "
 315                "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
 316                "Truecolor",
 317                screen_info.rsvd_size,
 318                screen_info.red_size,
 319                screen_info.green_size,
 320                screen_info.blue_size,
 321                screen_info.rsvd_pos,
 322                screen_info.red_pos,
 323                screen_info.green_pos,
 324                screen_info.blue_pos);
 325
 326         efifb_fix.ypanstep  = 0;
 327         efifb_fix.ywrapstep = 0;
 328
 329         info->fbops = &efifb_ops;
 330         info->var = efifb_defined;
 331         info->fix = efifb_fix;
 332         info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE;
 333
 334         orientation = drm_get_panel_orientation_quirk(efifb_defined.xres,
 335                                                       efifb_defined.yres);
 336         switch (orientation) {
 337         default:
 338                 info->fbcon_rotate_hint = FB_ROTATE_UR;
 339                 break;
 340         case DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP:
 341                 info->fbcon_rotate_hint = FB_ROTATE_UD;
 342                 break;
 343         case DRM_MODE_PANEL_ORIENTATION_LEFT_UP:
 344                 info->fbcon_rotate_hint = FB_ROTATE_CCW;
 345                 break;
 346         case DRM_MODE_PANEL_ORIENTATION_RIGHT_UP:
 347                 info->fbcon_rotate_hint = FB_ROTATE_CW;
 348                 break;
 349         }
 350
 351         err = sysfs_create_groups(&dev->dev.kobj, efifb_groups);
 352         if (err) {
 353                 pr_err("efifb: cannot add sysfs attrs\n");
 354                 goto err_unmap;
 355         }
 356         err = fb_alloc_cmap(&info->cmap, 256, 0);
 357         if (err < 0) {
 358                 pr_err("efifb: cannot allocate colormap\n");
 359                 goto err_groups;
 360         }
 361         err = register_framebuffer(info);
 362         if (err < 0) {
 363                 pr_err("efifb: cannot register framebuffer\n");
 364                 goto err_fb_dealoc;
 365         }
 366         fb_info(info, "%s frame buffer device\n", info->fix.id);
 367         return 0;
 368
 369 err_fb_dealoc:
 370         fb_dealloc_cmap(&info->cmap);
 371 err_groups:
 372         sysfs_remove_groups(&dev->dev.kobj, efifb_groups);
 373 err_unmap:
 374         iounmap(info->screen_base);
 375 err_release_fb:
 376         framebuffer_release(info);
 377 err_release_mem:
 378         if (request_mem_succeeded)
 379                 release_mem_region(efifb_fix.smem_start, size_total);
 380         return err;
 381 }
 382
 383 static int efifb_remove(struct platform_device *pdev)
 384 {
 385         struct fb_info *info = platform_get_drvdata(pdev);
 386
 387         unregister_framebuffer(info);
 388         sysfs_remove_groups(&pdev->dev.kobj, efifb_groups);
 389         framebuffer_release(info);
 390
 391         return 0;
 392 }
 393
 394 static struct platform_driver efifb_driver = {
 395         .driver = {
 396                 .name = "efi-framebuffer",
 397         },
 398         .probe = efifb_probe,
 399         .remove = efifb_remove,
 400 };
 401
 402 builtin_platform_driver(efifb_driver);
 403
 404 #if defined(CONFIG_PCI)
 405
 406 static void record_efifb_bar_resource(struct pci_dev *dev, int idx, u64 offset)
 407 {
 408         u16 word;
 409
 410         efifb_pci_dev = dev;
 411
 412         pci_read_config_word(dev, PCI_COMMAND, &word);
 413         if (!(word & PCI_COMMAND_MEMORY)) {
 414                 pci_dev_disabled = true;
 415                 dev_err(&dev->dev,
 416                         "BAR %d: assigned to efifb but device is disabled!\n",
 417                         idx);
 418                 return;
 419         }
 420
 421         bar_resource = &dev->resource[idx];
 422         bar_offset = offset;
 423
 424         dev_info(&dev->dev, "BAR %d: assigned to efifb\n", idx);
 425 }
 426
 427 static void efifb_fixup_resources(struct pci_dev *dev)
 428 {
 429         u64 base = screen_info.lfb_base;
 430         u64 size = screen_info.lfb_size;
 431         int i;
 432
 433         if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
 434                 return;
 435
 436         if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
 437                 base |= (u64)screen_info.ext_lfb_base << 32;
 438
 439         if (!base)
 440                 return;
 441
 442         for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
 443                 struct resource *res = &dev->resource[i];
 444
 445                 if (!(res->flags & IORESOURCE_MEM))
 446                         continue;
 447
 448                 if (res->start <= base && res->end >= base + size - 1) {
 449                         record_efifb_bar_resource(dev, i, base - res->start);
 450                         break;
 451                 }
 452         }
 453 }
 454 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY,
 455                                16, efifb_fixup_resources);
 456
 457 #endif