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 <[email protected]>
   6  * Original efi driver written by Gerd Knorr <[email protected]>
   7  *
   8  */
   9
  10 #include <linux/aperture.h>
  11 #include <linux/kernel.h>
  12 #include <linux/efi.h>
  13 #include <linux/efi-bgrt.h>
  14 #include <linux/errno.h>
  15 #include <linux/fb.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/printk.h>
  18 #include <linux/screen_info.h>
  19 #include <video/vga.h>
  20 #include <asm/efi.h>
  21 #include <drm/drm_utils.h> /* For drm_get_panel_orientation_quirk */
  22 #include <drm/drm_connector.h>  /* For DRM_MODE_PANEL_ORIENTATION_* */
  23
  24 struct bmp_file_header {
  25         u16 id;
  26         u32 file_size;
  27         u32 reserved;
  28         u32 bitmap_offset;
  29 } __packed;
  30
  31 struct bmp_dib_header {
  32         u32 dib_header_size;
  33         s32 width;
  34         s32 height;
  35         u16 planes;
  36         u16 bpp;
  37         u32 compression;
  38         u32 bitmap_size;
  39         u32 horz_resolution;
  40         u32 vert_resolution;
  41         u32 colors_used;
  42         u32 colors_important;
  43 } __packed;
  44
  45 static bool use_bgrt = true;
  46 static bool request_mem_succeeded = false;
  47 static u64 mem_flags = EFI_MEMORY_WC | EFI_MEMORY_UC;
  48
  49 struct efifb_par {
  50         u32 pseudo_palette[16];
  51         resource_size_t base;
  52         resource_size_t size;
  53 };
  54
  55 static struct fb_var_screeninfo efifb_defined = {
  56         .activate               = FB_ACTIVATE_NOW,
  57         .height                 = -1,
  58         .width                  = -1,
  59         .right_margin           = 32,
  60         .upper_margin           = 16,
  61         .lower_margin           = 4,
  62         .vsync_len              = 4,
  63         .vmode                  = FB_VMODE_NONINTERLACED,
  64 };
  65
  66 static struct fb_fix_screeninfo efifb_fix = {
  67         .id                     = "EFI VGA",
  68         .type                   = FB_TYPE_PACKED_PIXELS,
  69         .accel                  = FB_ACCEL_NONE,
  70         .visual                 = FB_VISUAL_TRUECOLOR,
  71 };
  72
  73 static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
  74                            unsigned blue, unsigned transp,
  75                            struct fb_info *info)
  76 {
  77         /*
  78          *  Set a single color register. The values supplied are
  79          *  already rounded down to the hardware's capabilities
  80          *  (according to the entries in the `var' structure). Return
  81          *  != 0 for invalid regno.
  82          */
  83
  84         if (regno >= info->cmap.len)
  85                 return 1;
  86
  87         if (regno < 16) {
  88                 red   >>= 16 - info->var.red.length;
  89                 green >>= 16 - info->var.green.length;
  90                 blue  >>= 16 - info->var.blue.length;
  91                 ((u32 *)(info->pseudo_palette))[regno] =
  92                         (red   << info->var.red.offset)   |
  93                         (green << info->var.green.offset) |
  94                         (blue  << info->var.blue.offset);
  95         }
  96         return 0;
  97 }
  98
  99 /*
 100  * If fbcon deffered console takeover is configured, the intent is for the
 101  * framebuffer to show the boot graphics (e.g. vendor logo) until there is some
 102  * (error) message to display. But the boot graphics may have been destroyed by
 103  * e.g. option ROM output, detect this and restore the boot graphics.
 104  */
 105 #if defined CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER && \
 106     defined CONFIG_ACPI_BGRT
 107 static void efifb_copy_bmp(u8 *src, u32 *dst, int width, const struct screen_info *si)
 108 {
 109         u8 r, g, b;
 110
 111         while (width--) {
 112                 b = *src++;
 113                 g = *src++;
 114                 r = *src++;
 115                 *dst++ = (r << si->red_pos)   |
 116                          (g << si->green_pos) |
 117                          (b << si->blue_pos);
 118         }
 119 }
 120
 121 #ifdef CONFIG_X86
 122 /*
 123  * On x86 some firmwares use a low non native resolution for the display when
 124  * they have shown some text messages. While keeping the bgrt filled with info
 125  * for the native resolution. If the bgrt image intended for the native
 126  * resolution still fits, it will be displayed very close to the right edge of
 127  * the display looking quite bad. This function checks for this.
 128  */
 129 static bool efifb_bgrt_sanity_check(const struct screen_info *si, u32 bmp_width)
 130 {
 131         /*
 132          * All x86 firmwares horizontally center the image (the yoffset
 133          * calculations differ between boards, but xoffset is predictable).
 134          */
 135         u32 expected_xoffset = (si->lfb_width - bmp_width) / 2;
 136
 137         return bgrt_tab.image_offset_x == expected_xoffset;
 138 }
 139 #else
 140 static bool efifb_bgrt_sanity_check(const struct screen_info *si, u32 bmp_width)
 141 {
 142         return true;
 143 }
 144 #endif
 145
 146 static void efifb_show_boot_graphics(struct fb_info *info, const struct screen_info *si)
 147 {
 148         u32 bmp_width, bmp_height, bmp_pitch, dst_x, y, src_y;
 149         struct bmp_file_header *file_header;
 150         struct bmp_dib_header *dib_header;
 151         void *bgrt_image = NULL;
 152         u8 *dst = info->screen_base;
 153
 154         if (!use_bgrt)
 155                 return;
 156
 157         if (!bgrt_tab.image_address) {
 158                 pr_info("efifb: No BGRT, not showing boot graphics\n");
 159                 return;
 160         }
 161
 162         if (bgrt_tab.status & 0x06) {
 163                 pr_info("efifb: BGRT rotation bits set, not showing boot graphics\n");
 164                 return;
 165         }
 166
 167         /* Avoid flashing the logo if we're going to print std probe messages */
 168         if (console_loglevel > CONSOLE_LOGLEVEL_QUIET)
 169                 return;
 170
 171         /* bgrt_tab.status is unreliable, so we don't check it */
 172
 173         if (si->lfb_depth != 32) {
 174                 pr_info("efifb: not 32 bits, not showing boot graphics\n");
 175                 return;
 176         }
 177
 178         bgrt_image = memremap(bgrt_tab.image_address, bgrt_image_size,
 179                               MEMREMAP_WB);
 180         if (!bgrt_image) {
 181                 pr_warn("efifb: Ignoring BGRT: failed to map image memory\n");
 182                 return;
 183         }
 184
 185         if (bgrt_image_size < (sizeof(*file_header) + sizeof(*dib_header)))
 186                 goto error;
 187
 188         file_header = bgrt_image;
 189         if (file_header->id != 0x4d42 || file_header->reserved != 0)
 190                 goto error;
 191
 192         dib_header = bgrt_image + sizeof(*file_header);
 193         if (dib_header->dib_header_size != 40 || dib_header->width < 0 ||
 194             dib_header->planes != 1 || dib_header->bpp != 24 ||
 195             dib_header->compression != 0)
 196                 goto error;
 197
 198         bmp_width = dib_header->width;
 199         bmp_height = abs(dib_header->height);
 200         bmp_pitch = round_up(3 * bmp_width, 4);
 201
 202         if ((file_header->bitmap_offset + bmp_pitch * bmp_height) >
 203                                 bgrt_image_size)
 204                 goto error;
 205
 206         if ((bgrt_tab.image_offset_x + bmp_width) > si->lfb_width ||
 207             (bgrt_tab.image_offset_y + bmp_height) > si->lfb_height)
 208                 goto error;
 209
 210         if (!efifb_bgrt_sanity_check(si, bmp_width))
 211                 goto error;
 212
 213         pr_info("efifb: showing boot graphics\n");
 214
 215         for (y = 0; y < si->lfb_height; y++, dst += si->lfb_linelength) {
 216                 /* Only background? */
 217                 if (y < bgrt_tab.image_offset_y ||
 218                     y >= (bgrt_tab.image_offset_y + bmp_height)) {
 219                         memset(dst, 0, 4 * si->lfb_width);
 220                         continue;
 221                 }
 222
 223                 src_y = y - bgrt_tab.image_offset_y;
 224                 /* Positive header height means upside down row order */
 225                 if (dib_header->height > 0)
 226                         src_y = (bmp_height - 1) - src_y;
 227
 228                 memset(dst, 0, bgrt_tab.image_offset_x * 4);
 229                 dst_x = bgrt_tab.image_offset_x;
 230                 efifb_copy_bmp(bgrt_image + file_header->bitmap_offset +
 231                                             src_y * bmp_pitch,
 232                                (u32 *)dst + dst_x, bmp_width, si);
 233                 dst_x += bmp_width;
 234                 memset((u32 *)dst + dst_x, 0, (si->lfb_width - dst_x) * 4);
 235         }
 236
 237         memunmap(bgrt_image);
 238         return;
 239
 240 error:
 241         memunmap(bgrt_image);
 242         pr_warn("efifb: Ignoring BGRT: unexpected or invalid BMP data\n");
 243 }
 244 #else
 245 static inline void efifb_show_boot_graphics(struct fb_info *info, const struct screen_info *si)
 246 { }
 247 #endif
 248
 249 /*
 250  * fb_ops.fb_destroy is called by the last put_fb_info() call at the end
 251  * of unregister_framebuffer() or fb_release(). Do any cleanup here.
 252  */
 253 static void efifb_destroy(struct fb_info *info)
 254 {
 255         struct efifb_par *par = info->par;
 256
 257         if (info->screen_base) {
 258                 if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC))
 259                         iounmap(info->screen_base);
 260                 else
 261                         memunmap(info->screen_base);
 262         }
 263
 264         if (request_mem_succeeded)
 265                 release_mem_region(par->base, par->size);
 266         fb_dealloc_cmap(&info->cmap);
 267
 268         framebuffer_release(info);
 269 }
 270
 271 static const struct fb_ops efifb_ops = {
 272         .owner          = THIS_MODULE,
 273         FB_DEFAULT_IOMEM_OPS,
 274         .fb_destroy     = efifb_destroy,
 275         .fb_setcolreg   = efifb_setcolreg,
 276 };
 277
 278 static int efifb_setup(struct screen_info *si, char *options)
 279 {
 280         char *this_opt;
 281
 282         if (options && *options) {
 283                 while ((this_opt = strsep(&options, ",")) != NULL) {
 284                         if (!*this_opt) continue;
 285
 286                         efifb_setup_from_dmi(si, this_opt);
 287
 288                         if (!strncmp(this_opt, "base:", 5))
 289                                 si->lfb_base = simple_strtoul(this_opt+5, NULL, 0);
 290                         else if (!strncmp(this_opt, "stride:", 7))
 291                                 si->lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
 292                         else if (!strncmp(this_opt, "height:", 7))
 293                                 si->lfb_height = simple_strtoul(this_opt+7, NULL, 0);
 294                         else if (!strncmp(this_opt, "width:", 6))
 295                                 si->lfb_width = simple_strtoul(this_opt+6, NULL, 0);
 296                         else if (!strcmp(this_opt, "nowc"))
 297                                 mem_flags &= ~EFI_MEMORY_WC;
 298                         else if (!strcmp(this_opt, "nobgrt"))
 299                                 use_bgrt = false;
 300                 }
 301         }
 302
 303         return 0;
 304 }
 305
 306 static inline bool fb_base_is_valid(struct screen_info *si)
 307 {
 308         if (si->lfb_base)
 309                 return true;
 310
 311         if (!(si->capabilities & VIDEO_CAPABILITY_64BIT_BASE))
 312                 return false;
 313
 314         if (si->ext_lfb_base)
 315                 return true;
 316
 317         return false;
 318 }
 319
 320 #define efifb_attr_decl(name, fmt)                                      \
 321 static ssize_t name##_show(struct device *dev,                          \
 322                            struct device_attribute *attr,               \
 323                            char *buf)                                   \
 324 {                                                                       \
 325         struct screen_info *si = dev_get_drvdata(dev);                  \
 326         if (!si)                                                        \
 327                 return -ENODEV;                                         \
 328         return sprintf(buf, fmt "\n", (si->lfb_##name));                \
 329 }                                                                       \
 330 static DEVICE_ATTR_RO(name)
 331
 332 efifb_attr_decl(base, "0x%x");
 333 efifb_attr_decl(linelength, "%u");
 334 efifb_attr_decl(height, "%u");
 335 efifb_attr_decl(width, "%u");
 336 efifb_attr_decl(depth, "%u");
 337
 338 static struct attribute *efifb_attrs[] = {
 339         &dev_attr_base.attr,
 340         &dev_attr_linelength.attr,
 341         &dev_attr_width.attr,
 342         &dev_attr_height.attr,
 343         &dev_attr_depth.attr,
 344         NULL
 345 };
 346 ATTRIBUTE_GROUPS(efifb);
 347
 348 static int efifb_probe(struct platform_device *dev)
 349 {
 350         struct screen_info *si;
 351         struct fb_info *info;
 352         struct efifb_par *par;
 353         int err, orientation;
 354         unsigned int size_vmode;
 355         unsigned int size_remap;
 356         unsigned int size_total;
 357         char *option = NULL;
 358         efi_memory_desc_t md;
 359
 360         /*
 361          * If we fail probing the device, the kernel might try a different
 362          * driver. We get a copy of the attached screen_info, so that we can
 363          * modify its values without affecting later drivers.
 364          */
 365         si = dev_get_platdata(&dev->dev);
 366         if (!si)
 367                 return -ENODEV;
 368         si = devm_kmemdup(&dev->dev, si, sizeof(*si), GFP_KERNEL);
 369         if (!si)
 370                 return -ENOMEM;
 371
 372         dev_set_drvdata(&dev->dev, si);
 373
 374         if (si->orig_video_isVGA != VIDEO_TYPE_EFI)
 375                 return -ENODEV;
 376
 377         if (fb_get_options("efifb", &option))
 378                 return -ENODEV;
 379         efifb_setup(si, option);
 380
 381         /* We don't get linelength from UGA Draw Protocol, only from
 382          * EFI Graphics Protocol.  So if it's not in DMI, and it's not
 383          * passed in from the user, we really can't use the framebuffer.
 384          */
 385         if (!si->lfb_linelength)
 386                 return -ENODEV;
 387
 388         if (!si->lfb_depth)
 389                 si->lfb_depth = 32;
 390         if (!si->pages)
 391                 si->pages = 1;
 392         if (!fb_base_is_valid(si)) {
 393                 printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
 394                 return -ENODEV;
 395         }
 396         printk(KERN_INFO "efifb: probing for efifb\n");
 397
 398         /* just assume they're all unset if any are */
 399         if (!si->blue_size) {
 400                 si->blue_size = 8;
 401                 si->blue_pos = 0;
 402                 si->green_size = 8;
 403                 si->green_pos = 8;
 404                 si->red_size = 8;
 405                 si->red_pos = 16;
 406                 si->rsvd_size = 8;
 407                 si->rsvd_pos = 24;
 408         }
 409
 410         efifb_fix.smem_start = __screen_info_lfb_base(si);
 411
 412         efifb_defined.bits_per_pixel = si->lfb_depth;
 413         efifb_defined.xres = si->lfb_width;
 414         efifb_defined.yres = si->lfb_height;
 415         efifb_fix.line_length = si->lfb_linelength;
 416
 417         /*   size_vmode -- that is the amount of memory needed for the
 418          *                 used video mode, i.e. the minimum amount of
 419          *                 memory we need. */
 420         size_vmode = efifb_defined.yres * efifb_fix.line_length;
 421
 422         /*   size_total -- all video memory we have. Used for
 423          *                 entries, ressource allocation and bounds
 424          *                 checking. */
 425         size_total = si->lfb_size;
 426         if (size_total < size_vmode)
 427                 size_total = size_vmode;
 428
 429         /*   size_remap -- the amount of video memory we are going to
 430          *                 use for efifb.  With modern cards it is no
 431          *                 option to simply use size_total as that
 432          *                 wastes plenty of kernel address space. */
 433         size_remap  = size_vmode * 2;
 434         if (size_remap > size_total)
 435                 size_remap = size_total;
 436         if (size_remap % PAGE_SIZE)
 437                 size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
 438         efifb_fix.smem_len = size_remap;
 439
 440         if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
 441                 request_mem_succeeded = true;
 442         } else {
 443                 /* We cannot make this fatal. Sometimes this comes from magic
 444                    spaces our resource handlers simply don't know about */
 445                 pr_warn("efifb: cannot reserve video memory at 0x%lx\n",
 446                         efifb_fix.smem_start);
 447         }
 448
 449         info = framebuffer_alloc(sizeof(*par), &dev->dev);
 450         if (!info) {
 451                 err = -ENOMEM;
 452                 goto err_release_mem;
 453         }
 454         par = info->par;
 455         info->pseudo_palette = par->pseudo_palette;
 456
 457         par->base = efifb_fix.smem_start;
 458         par->size = size_remap;
 459
 460         if (efi_enabled(EFI_MEMMAP) &&
 461             !efi_mem_desc_lookup(efifb_fix.smem_start, &md)) {
 462                 if ((efifb_fix.smem_start + efifb_fix.smem_len) >
 463                     (md.phys_addr + (md.num_pages << EFI_PAGE_SHIFT))) {
 464                         pr_err("efifb: video memory @ 0x%lx spans multiple EFI memory regions\n",
 465                                efifb_fix.smem_start);
 466                         err = -EIO;
 467                         goto err_release_fb;
 468                 }
 469                 /*
 470                  * If the UEFI memory map covers the efifb region, we may only
 471                  * remap it using the attributes the memory map prescribes.
 472                  */
 473                 md.attribute &= EFI_MEMORY_UC | EFI_MEMORY_WC |
 474                                 EFI_MEMORY_WT | EFI_MEMORY_WB;
 475                 if (md.attribute) {
 476                         mem_flags |= EFI_MEMORY_WT | EFI_MEMORY_WB;
 477                         mem_flags &= md.attribute;
 478                 }
 479         }
 480         if (mem_flags & EFI_MEMORY_WC)
 481                 info->screen_base = ioremap_wc(efifb_fix.smem_start,
 482                                                efifb_fix.smem_len);
 483         else if (mem_flags & EFI_MEMORY_UC)
 484                 info->screen_base = ioremap(efifb_fix.smem_start,
 485                                             efifb_fix.smem_len);
 486         else if (mem_flags & EFI_MEMORY_WT)
 487                 info->screen_base = memremap(efifb_fix.smem_start,
 488                                              efifb_fix.smem_len, MEMREMAP_WT);
 489         else if (mem_flags & EFI_MEMORY_WB)
 490                 info->screen_base = memremap(efifb_fix.smem_start,
 491                                              efifb_fix.smem_len, MEMREMAP_WB);
 492         if (!info->screen_base) {
 493                 pr_err("efifb: abort, cannot remap video memory 0x%x @ 0x%lx\n",
 494                         efifb_fix.smem_len, efifb_fix.smem_start);
 495                 err = -EIO;
 496                 goto err_release_fb;
 497         }
 498
 499         efifb_show_boot_graphics(info, si);
 500
 501         pr_info("efifb: framebuffer at 0x%lx, using %dk, total %dk\n",
 502                efifb_fix.smem_start, size_remap/1024, size_total/1024);
 503         pr_info("efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
 504                efifb_defined.xres, efifb_defined.yres,
 505                efifb_defined.bits_per_pixel, efifb_fix.line_length,
 506                si->pages);
 507
 508         efifb_defined.xres_virtual = efifb_defined.xres;
 509         efifb_defined.yres_virtual = efifb_fix.smem_len /
 510                                         efifb_fix.line_length;
 511         pr_info("efifb: scrolling: redraw\n");
 512         efifb_defined.yres_virtual = efifb_defined.yres;
 513
 514         /* some dummy values for timing to make fbset happy */
 515         efifb_defined.pixclock     = 10000000 / efifb_defined.xres *
 516                                         1000 / efifb_defined.yres;
 517         efifb_defined.left_margin  = (efifb_defined.xres / 8) & 0xf8;
 518         efifb_defined.hsync_len    = (efifb_defined.xres / 8) & 0xf8;
 519
 520         efifb_defined.red.offset    = si->red_pos;
 521         efifb_defined.red.length    = si->red_size;
 522         efifb_defined.green.offset  = si->green_pos;
 523         efifb_defined.green.length  = si->green_size;
 524         efifb_defined.blue.offset   = si->blue_pos;
 525         efifb_defined.blue.length   = si->blue_size;
 526         efifb_defined.transp.offset = si->rsvd_pos;
 527         efifb_defined.transp.length = si->rsvd_size;
 528
 529         pr_info("efifb: %s: "
 530                "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
 531                "Truecolor",
 532                si->rsvd_size,
 533                si->red_size,
 534                si->green_size,
 535                si->blue_size,
 536                si->rsvd_pos,
 537                si->red_pos,
 538                si->green_pos,
 539                si->blue_pos);
 540
 541         efifb_fix.ypanstep  = 0;
 542         efifb_fix.ywrapstep = 0;
 543
 544         info->fbops = &efifb_ops;
 545         info->var = efifb_defined;
 546         info->fix = efifb_fix;
 547
 548         orientation = drm_get_panel_orientation_quirk(efifb_defined.xres,
 549                                                       efifb_defined.yres);
 550         switch (orientation) {
 551         default:
 552                 info->fbcon_rotate_hint = FB_ROTATE_UR;
 553                 break;
 554         case DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP:
 555                 info->fbcon_rotate_hint = FB_ROTATE_UD;
 556                 break;
 557         case DRM_MODE_PANEL_ORIENTATION_LEFT_UP:
 558                 info->fbcon_rotate_hint = FB_ROTATE_CCW;
 559                 break;
 560         case DRM_MODE_PANEL_ORIENTATION_RIGHT_UP:
 561                 info->fbcon_rotate_hint = FB_ROTATE_CW;
 562                 break;
 563         }
 564
 565         err = fb_alloc_cmap(&info->cmap, 256, 0);
 566         if (err < 0) {
 567                 pr_err("efifb: cannot allocate colormap\n");
 568                 goto err_unmap;
 569         }
 570
 571         err = devm_aperture_acquire_for_platform_device(dev, par->base, par->size);
 572         if (err) {
 573                 pr_err("efifb: cannot acquire aperture\n");
 574                 goto err_fb_dealloc_cmap;
 575         }
 576         err = devm_register_framebuffer(&dev->dev, info);
 577         if (err < 0) {
 578                 pr_err("efifb: cannot register framebuffer\n");
 579                 goto err_fb_dealloc_cmap;
 580         }
 581         fb_info(info, "%s frame buffer device\n", info->fix.id);
 582         return 0;
 583
 584 err_fb_dealloc_cmap:
 585         fb_dealloc_cmap(&info->cmap);
 586 err_unmap:
 587         if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC))
 588                 iounmap(info->screen_base);
 589         else
 590                 memunmap(info->screen_base);
 591 err_release_fb:
 592         framebuffer_release(info);
 593 err_release_mem:
 594         if (request_mem_succeeded)
 595                 release_mem_region(efifb_fix.smem_start, size_total);
 596         return err;
 597 }
 598
 599 static struct platform_driver efifb_driver = {
 600         .driver = {
 601                 .name = "efi-framebuffer",
 602                 .dev_groups = efifb_groups,
 603         },
 604         .probe = efifb_probe,
 605 };
 606
 607 builtin_platform_driver(efifb_driver);