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 u64 mem_flags = EFI_MEMORY_WC | EFI_MEMORY_UC; 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 if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC)) 73 iounmap(info->screen_base); 74 else 75 memunmap(info->screen_base); 76 } 77 if (request_mem_succeeded) 78 release_mem_region(info->apertures->ranges[0].base, 79 info->apertures->ranges[0].size); 80 fb_dealloc_cmap(&info->cmap); 81 } 82 83 static struct fb_ops efifb_ops = { 84 .owner = THIS_MODULE, 85 .fb_destroy = efifb_destroy, 86 .fb_setcolreg = efifb_setcolreg, 87 .fb_fillrect = cfb_fillrect, 88 .fb_copyarea = cfb_copyarea, 89 .fb_imageblit = cfb_imageblit, 90 }; 91 92 static int efifb_setup(char *options) 93 { 94 char *this_opt; 95 96 if (options && *options) { 97 while ((this_opt = strsep(&options, ",")) != NULL) { 98 if (!*this_opt) continue; 99 100 efifb_setup_from_dmi(&screen_info, this_opt); 101 102 if (!strncmp(this_opt, "base:", 5)) 103 screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0); 104 else if (!strncmp(this_opt, "stride:", 7)) 105 screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4; 106 else if (!strncmp(this_opt, "height:", 7)) 107 screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0); 108 else if (!strncmp(this_opt, "width:", 6)) 109 screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0); 110 else if (!strcmp(this_opt, "nowc")) 111 mem_flags &= ~EFI_MEMORY_WC; 112 } 113 } 114 115 return 0; 116 } 117 118 static inline bool fb_base_is_valid(void) 119 { 120 if (screen_info.lfb_base) 121 return true; 122 123 if (!(screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)) 124 return false; 125 126 if (screen_info.ext_lfb_base) 127 return true; 128 129 return false; 130 } 131 132 #define efifb_attr_decl(name, fmt) \ 133 static ssize_t name##_show(struct device *dev, \ 134 struct device_attribute *attr, \ 135 char *buf) \ 136 { \ 137 return sprintf(buf, fmt "\n", (screen_info.lfb_##name)); \ 138 } \ 139 static DEVICE_ATTR_RO(name) 140 141 efifb_attr_decl(base, "0x%x"); 142 efifb_attr_decl(linelength, "%u"); 143 efifb_attr_decl(height, "%u"); 144 efifb_attr_decl(width, "%u"); 145 efifb_attr_decl(depth, "%u"); 146 147 static struct attribute *efifb_attrs[] = { 148 &dev_attr_base.attr, 149 &dev_attr_linelength.attr, 150 &dev_attr_width.attr, 151 &dev_attr_height.attr, 152 &dev_attr_depth.attr, 153 NULL 154 }; 155 ATTRIBUTE_GROUPS(efifb); 156 157 static bool pci_dev_disabled; /* FB base matches BAR of a disabled device */ 158 159 static struct pci_dev *efifb_pci_dev; /* dev with BAR covering the efifb */ 160 static struct resource *bar_resource; 161 static u64 bar_offset; 162 163 static int efifb_probe(struct platform_device *dev) 164 { 165 struct fb_info *info; 166 int err, orientation; 167 unsigned int size_vmode; 168 unsigned int size_remap; 169 unsigned int size_total; 170 char *option = NULL; 171 efi_memory_desc_t md; 172 173 if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI || pci_dev_disabled) 174 return -ENODEV; 175 176 if (fb_get_options("efifb", &option)) 177 return -ENODEV; 178 efifb_setup(option); 179 180 /* We don't get linelength from UGA Draw Protocol, only from 181 * EFI Graphics Protocol. So if it's not in DMI, and it's not 182 * passed in from the user, we really can't use the framebuffer. 183 */ 184 if (!screen_info.lfb_linelength) 185 return -ENODEV; 186 187 if (!screen_info.lfb_depth) 188 screen_info.lfb_depth = 32; 189 if (!screen_info.pages) 190 screen_info.pages = 1; 191 if (!fb_base_is_valid()) { 192 printk(KERN_DEBUG "efifb: invalid framebuffer address\n"); 193 return -ENODEV; 194 } 195 printk(KERN_INFO "efifb: probing for efifb\n"); 196 197 /* just assume they're all unset if any are */ 198 if (!screen_info.blue_size) { 199 screen_info.blue_size = 8; 200 screen_info.blue_pos = 0; 201 screen_info.green_size = 8; 202 screen_info.green_pos = 8; 203 screen_info.red_size = 8; 204 screen_info.red_pos = 16; 205 screen_info.rsvd_size = 8; 206 screen_info.rsvd_pos = 24; 207 } 208 209 efifb_fix.smem_start = screen_info.lfb_base; 210 211 if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) { 212 u64 ext_lfb_base; 213 214 ext_lfb_base = (u64)(unsigned long)screen_info.ext_lfb_base << 32; 215 efifb_fix.smem_start |= ext_lfb_base; 216 } 217 218 if (bar_resource && 219 bar_resource->start + bar_offset != efifb_fix.smem_start) { 220 dev_info(&efifb_pci_dev->dev, 221 "BAR has moved, updating efifb address\n"); 222 efifb_fix.smem_start = bar_resource->start + bar_offset; 223 } 224 225 efifb_defined.bits_per_pixel = screen_info.lfb_depth; 226 efifb_defined.xres = screen_info.lfb_width; 227 efifb_defined.yres = screen_info.lfb_height; 228 efifb_fix.line_length = screen_info.lfb_linelength; 229 230 /* size_vmode -- that is the amount of memory needed for the 231 * used video mode, i.e. the minimum amount of 232 * memory we need. */ 233 size_vmode = efifb_defined.yres * efifb_fix.line_length; 234 235 /* size_total -- all video memory we have. Used for 236 * entries, ressource allocation and bounds 237 * checking. */ 238 size_total = screen_info.lfb_size; 239 if (size_total < size_vmode) 240 size_total = size_vmode; 241 242 /* size_remap -- the amount of video memory we are going to 243 * use for efifb. With modern cards it is no 244 * option to simply use size_total as that 245 * wastes plenty of kernel address space. */ 246 size_remap = size_vmode * 2; 247 if (size_remap > size_total) 248 size_remap = size_total; 249 if (size_remap % PAGE_SIZE) 250 size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE); 251 efifb_fix.smem_len = size_remap; 252 253 if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) { 254 request_mem_succeeded = true; 255 } else { 256 /* We cannot make this fatal. Sometimes this comes from magic 257 spaces our resource handlers simply don't know about */ 258 pr_warn("efifb: cannot reserve video memory at 0x%lx\n", 259 efifb_fix.smem_start); 260 } 261 262 info = framebuffer_alloc(sizeof(u32) * 16, &dev->dev); 263 if (!info) { 264 pr_err("efifb: cannot allocate framebuffer\n"); 265 err = -ENOMEM; 266 goto err_release_mem; 267 } 268 platform_set_drvdata(dev, info); 269 info->pseudo_palette = info->par; 270 info->par = NULL; 271 272 info->apertures = alloc_apertures(1); 273 if (!info->apertures) { 274 err = -ENOMEM; 275 goto err_release_fb; 276 } 277 info->apertures->ranges[0].base = efifb_fix.smem_start; 278 info->apertures->ranges[0].size = size_remap; 279 280 if (!efi_mem_desc_lookup(efifb_fix.smem_start, &md)) { 281 if ((efifb_fix.smem_start + efifb_fix.smem_len) > 282 (md.phys_addr + (md.num_pages << EFI_PAGE_SHIFT))) { 283 pr_err("efifb: video memory @ 0x%lx spans multiple EFI memory regions\n", 284 efifb_fix.smem_start); 285 err = -EIO; 286 goto err_release_fb; 287 } 288 /* 289 * If the UEFI memory map covers the efifb region, we may only 290 * remap it using the attributes the memory map prescribes. 291 */ 292 mem_flags |= EFI_MEMORY_WT | EFI_MEMORY_WB; 293 mem_flags &= md.attribute; 294 } 295 if (mem_flags & EFI_MEMORY_WC) 296 info->screen_base = ioremap_wc(efifb_fix.smem_start, 297 efifb_fix.smem_len); 298 else if (mem_flags & EFI_MEMORY_UC) 299 info->screen_base = ioremap(efifb_fix.smem_start, 300 efifb_fix.smem_len); 301 else if (mem_flags & EFI_MEMORY_WT) 302 info->screen_base = memremap(efifb_fix.smem_start, 303 efifb_fix.smem_len, MEMREMAP_WT); 304 else if (mem_flags & EFI_MEMORY_WB) 305 info->screen_base = memremap(efifb_fix.smem_start, 306 efifb_fix.smem_len, MEMREMAP_WB); 307 if (!info->screen_base) { 308 pr_err("efifb: abort, cannot remap video memory 0x%x @ 0x%lx\n", 309 efifb_fix.smem_len, efifb_fix.smem_start); 310 err = -EIO; 311 goto err_release_fb; 312 } 313 314 pr_info("efifb: framebuffer at 0x%lx, using %dk, total %dk\n", 315 efifb_fix.smem_start, size_remap/1024, size_total/1024); 316 pr_info("efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n", 317 efifb_defined.xres, efifb_defined.yres, 318 efifb_defined.bits_per_pixel, efifb_fix.line_length, 319 screen_info.pages); 320 321 efifb_defined.xres_virtual = efifb_defined.xres; 322 efifb_defined.yres_virtual = efifb_fix.smem_len / 323 efifb_fix.line_length; 324 pr_info("efifb: scrolling: redraw\n"); 325 efifb_defined.yres_virtual = efifb_defined.yres; 326 327 /* some dummy values for timing to make fbset happy */ 328 efifb_defined.pixclock = 10000000 / efifb_defined.xres * 329 1000 / efifb_defined.yres; 330 efifb_defined.left_margin = (efifb_defined.xres / 8) & 0xf8; 331 efifb_defined.hsync_len = (efifb_defined.xres / 8) & 0xf8; 332 333 efifb_defined.red.offset = screen_info.red_pos; 334 efifb_defined.red.length = screen_info.red_size; 335 efifb_defined.green.offset = screen_info.green_pos; 336 efifb_defined.green.length = screen_info.green_size; 337 efifb_defined.blue.offset = screen_info.blue_pos; 338 efifb_defined.blue.length = screen_info.blue_size; 339 efifb_defined.transp.offset = screen_info.rsvd_pos; 340 efifb_defined.transp.length = screen_info.rsvd_size; 341 342 pr_info("efifb: %s: " 343 "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n", 344 "Truecolor", 345 screen_info.rsvd_size, 346 screen_info.red_size, 347 screen_info.green_size, 348 screen_info.blue_size, 349 screen_info.rsvd_pos, 350 screen_info.red_pos, 351 screen_info.green_pos, 352 screen_info.blue_pos); 353 354 efifb_fix.ypanstep = 0; 355 efifb_fix.ywrapstep = 0; 356 357 info->fbops = &efifb_ops; 358 info->var = efifb_defined; 359 info->fix = efifb_fix; 360 info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE; 361 362 orientation = drm_get_panel_orientation_quirk(efifb_defined.xres, 363 efifb_defined.yres); 364 switch (orientation) { 365 default: 366 info->fbcon_rotate_hint = FB_ROTATE_UR; 367 break; 368 case DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP: 369 info->fbcon_rotate_hint = FB_ROTATE_UD; 370 break; 371 case DRM_MODE_PANEL_ORIENTATION_LEFT_UP: 372 info->fbcon_rotate_hint = FB_ROTATE_CCW; 373 break; 374 case DRM_MODE_PANEL_ORIENTATION_RIGHT_UP: 375 info->fbcon_rotate_hint = FB_ROTATE_CW; 376 break; 377 } 378 379 err = sysfs_create_groups(&dev->dev.kobj, efifb_groups); 380 if (err) { 381 pr_err("efifb: cannot add sysfs attrs\n"); 382 goto err_unmap; 383 } 384 err = fb_alloc_cmap(&info->cmap, 256, 0); 385 if (err < 0) { 386 pr_err("efifb: cannot allocate colormap\n"); 387 goto err_groups; 388 } 389 err = register_framebuffer(info); 390 if (err < 0) { 391 pr_err("efifb: cannot register framebuffer\n"); 392 goto err_fb_dealoc; 393 } 394 fb_info(info, "%s frame buffer device\n", info->fix.id); 395 return 0; 396 397 err_fb_dealoc: 398 fb_dealloc_cmap(&info->cmap); 399 err_groups: 400 sysfs_remove_groups(&dev->dev.kobj, efifb_groups); 401 err_unmap: 402 if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC)) 403 iounmap(info->screen_base); 404 else 405 memunmap(info->screen_base); 406 err_release_fb: 407 framebuffer_release(info); 408 err_release_mem: 409 if (request_mem_succeeded) 410 release_mem_region(efifb_fix.smem_start, size_total); 411 return err; 412 } 413 414 static int efifb_remove(struct platform_device *pdev) 415 { 416 struct fb_info *info = platform_get_drvdata(pdev); 417 418 unregister_framebuffer(info); 419 sysfs_remove_groups(&pdev->dev.kobj, efifb_groups); 420 framebuffer_release(info); 421 422 return 0; 423 } 424 425 static struct platform_driver efifb_driver = { 426 .driver = { 427 .name = "efi-framebuffer", 428 }, 429 .probe = efifb_probe, 430 .remove = efifb_remove, 431 }; 432 433 builtin_platform_driver(efifb_driver); 434 435 #if defined(CONFIG_PCI) 436 437 static void record_efifb_bar_resource(struct pci_dev *dev, int idx, u64 offset) 438 { 439 u16 word; 440 441 efifb_pci_dev = dev; 442 443 pci_read_config_word(dev, PCI_COMMAND, &word); 444 if (!(word & PCI_COMMAND_MEMORY)) { 445 pci_dev_disabled = true; 446 dev_err(&dev->dev, 447 "BAR %d: assigned to efifb but device is disabled!\n", 448 idx); 449 return; 450 } 451 452 bar_resource = &dev->resource[idx]; 453 bar_offset = offset; 454 455 dev_info(&dev->dev, "BAR %d: assigned to efifb\n", idx); 456 } 457 458 static void efifb_fixup_resources(struct pci_dev *dev) 459 { 460 u64 base = screen_info.lfb_base; 461 u64 size = screen_info.lfb_size; 462 int i; 463 464 if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI) 465 return; 466 467 if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) 468 base |= (u64)screen_info.ext_lfb_base << 32; 469 470 if (!base) 471 return; 472 473 for (i = 0; i <= PCI_STD_RESOURCE_END; i++) { 474 struct resource *res = &dev->resource[i]; 475 476 if (!(res->flags & IORESOURCE_MEM)) 477 continue; 478 479 if (res->start <= base && res->end >= base + size - 1) { 480 record_efifb_bar_resource(dev, i, base - res->start); 481 break; 482 } 483 } 484 } 485 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY, 486 16, efifb_fixup_resources); 487 488 #endif 489