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 458