xref: /openbmc/linux/drivers/video/fbdev/efifb.c (revision ae213c44)
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/efi-bgrt.h>
13 #include <linux/errno.h>
14 #include <linux/fb.h>
15 #include <linux/pci.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 static struct fb_var_screeninfo efifb_defined = {
50 	.activate		= FB_ACTIVATE_NOW,
51 	.height			= -1,
52 	.width			= -1,
53 	.right_margin		= 32,
54 	.upper_margin		= 16,
55 	.lower_margin		= 4,
56 	.vsync_len		= 4,
57 	.vmode			= FB_VMODE_NONINTERLACED,
58 };
59 
60 static struct fb_fix_screeninfo efifb_fix = {
61 	.id			= "EFI VGA",
62 	.type			= FB_TYPE_PACKED_PIXELS,
63 	.accel			= FB_ACCEL_NONE,
64 	.visual			= FB_VISUAL_TRUECOLOR,
65 };
66 
67 static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
68 			   unsigned blue, unsigned transp,
69 			   struct fb_info *info)
70 {
71 	/*
72 	 *  Set a single color register. The values supplied are
73 	 *  already rounded down to the hardware's capabilities
74 	 *  (according to the entries in the `var' structure). Return
75 	 *  != 0 for invalid regno.
76 	 */
77 
78 	if (regno >= info->cmap.len)
79 		return 1;
80 
81 	if (regno < 16) {
82 		red   >>= 16 - info->var.red.length;
83 		green >>= 16 - info->var.green.length;
84 		blue  >>= 16 - info->var.blue.length;
85 		((u32 *)(info->pseudo_palette))[regno] =
86 			(red   << info->var.red.offset)   |
87 			(green << info->var.green.offset) |
88 			(blue  << info->var.blue.offset);
89 	}
90 	return 0;
91 }
92 
93 /*
94  * If fbcon deffered console takeover is configured, the intent is for the
95  * framebuffer to show the boot graphics (e.g. vendor logo) until there is some
96  * (error) message to display. But the boot graphics may have been destroyed by
97  * e.g. option ROM output, detect this and restore the boot graphics.
98  */
99 #if defined CONFIG_FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER && \
100     defined CONFIG_ACPI_BGRT
101 static void efifb_copy_bmp(u8 *src, u32 *dst, int width, struct screen_info *si)
102 {
103 	u8 r, g, b;
104 
105 	while (width--) {
106 		b = *src++;
107 		g = *src++;
108 		r = *src++;
109 		*dst++ = (r << si->red_pos)   |
110 			 (g << si->green_pos) |
111 			 (b << si->blue_pos);
112 	}
113 }
114 
115 #ifdef CONFIG_X86
116 /*
117  * On x86 some firmwares use a low non native resolution for the display when
118  * they have shown some text messages. While keeping the bgrt filled with info
119  * for the native resolution. If the bgrt image intended for the native
120  * resolution still fits, it will be displayed very close to the right edge of
121  * the display looking quite bad. This function checks for this.
122  */
123 static bool efifb_bgrt_sanity_check(struct screen_info *si, u32 bmp_width)
124 {
125 	static const int default_resolutions[][2] = {
126 		{  800,  600 },
127 		{ 1024,  768 },
128 		{ 1280, 1024 },
129 	};
130 	u32 i, right_margin;
131 
132 	for (i = 0; i < ARRAY_SIZE(default_resolutions); i++) {
133 		if (default_resolutions[i][0] == si->lfb_width &&
134 		    default_resolutions[i][1] == si->lfb_height)
135 			break;
136 	}
137 	/* If not a default resolution used for textmode, this should be fine */
138 	if (i >= ARRAY_SIZE(default_resolutions))
139 		return true;
140 
141 	/* If the right margin is 5 times smaller then the left one, reject */
142 	right_margin = si->lfb_width - (bgrt_tab.image_offset_x + bmp_width);
143 	if (right_margin < (bgrt_tab.image_offset_x / 5))
144 		return false;
145 
146 	return true;
147 }
148 #else
149 static bool efifb_bgrt_sanity_check(struct screen_info *si, u32 bmp_width)
150 {
151 	return true;
152 }
153 #endif
154 
155 static void efifb_show_boot_graphics(struct fb_info *info)
156 {
157 	u32 bmp_width, bmp_height, bmp_pitch, screen_pitch, dst_x, y, src_y;
158 	struct screen_info *si = &screen_info;
159 	struct bmp_file_header *file_header;
160 	struct bmp_dib_header *dib_header;
161 	void *bgrt_image = NULL;
162 	u8 *dst = info->screen_base;
163 
164 	if (!use_bgrt)
165 		return;
166 
167 	if (!bgrt_tab.image_address) {
168 		pr_info("efifb: No BGRT, not showing boot graphics\n");
169 		return;
170 	}
171 
172 	/* Avoid flashing the logo if we're going to print std probe messages */
173 	if (console_loglevel > CONSOLE_LOGLEVEL_QUIET)
174 		return;
175 
176 	/* bgrt_tab.status is unreliable, so we don't check it */
177 
178 	if (si->lfb_depth != 32) {
179 		pr_info("efifb: not 32 bits, not showing boot graphics\n");
180 		return;
181 	}
182 
183 	bgrt_image = memremap(bgrt_tab.image_address, bgrt_image_size,
184 			      MEMREMAP_WB);
185 	if (!bgrt_image) {
186 		pr_warn("efifb: Ignoring BGRT: failed to map image memory\n");
187 		return;
188 	}
189 
190 	if (bgrt_image_size < (sizeof(*file_header) + sizeof(*dib_header)))
191 		goto error;
192 
193 	file_header = bgrt_image;
194 	if (file_header->id != 0x4d42 || file_header->reserved != 0)
195 		goto error;
196 
197 	dib_header = bgrt_image + sizeof(*file_header);
198 	if (dib_header->dib_header_size != 40 || dib_header->width < 0 ||
199 	    dib_header->planes != 1 || dib_header->bpp != 24 ||
200 	    dib_header->compression != 0)
201 		goto error;
202 
203 	bmp_width = dib_header->width;
204 	bmp_height = abs(dib_header->height);
205 	bmp_pitch = round_up(3 * bmp_width, 4);
206 	screen_pitch = si->lfb_linelength;
207 
208 	if ((file_header->bitmap_offset + bmp_pitch * bmp_height) >
209 				bgrt_image_size)
210 		goto error;
211 
212 	if ((bgrt_tab.image_offset_x + bmp_width) > si->lfb_width ||
213 	    (bgrt_tab.image_offset_y + bmp_height) > si->lfb_height)
214 		goto error;
215 
216 	if (!efifb_bgrt_sanity_check(si, bmp_width))
217 		goto error;
218 
219 	pr_info("efifb: showing boot graphics\n");
220 
221 	for (y = 0; y < si->lfb_height; y++, dst += si->lfb_linelength) {
222 		/* Only background? */
223 		if (y < bgrt_tab.image_offset_y ||
224 		    y >= (bgrt_tab.image_offset_y + bmp_height)) {
225 			memset(dst, 0, 4 * si->lfb_width);
226 			continue;
227 		}
228 
229 		src_y = y - bgrt_tab.image_offset_y;
230 		/* Positive header height means upside down row order */
231 		if (dib_header->height > 0)
232 			src_y = (bmp_height - 1) - src_y;
233 
234 		memset(dst, 0, bgrt_tab.image_offset_x * 4);
235 		dst_x = bgrt_tab.image_offset_x;
236 		efifb_copy_bmp(bgrt_image + file_header->bitmap_offset +
237 					    src_y * bmp_pitch,
238 			       (u32 *)dst + dst_x, bmp_width, si);
239 		dst_x += bmp_width;
240 		memset((u32 *)dst + dst_x, 0, (si->lfb_width - dst_x) * 4);
241 	}
242 
243 	memunmap(bgrt_image);
244 	return;
245 
246 error:
247 	memunmap(bgrt_image);
248 	pr_warn("efifb: Ignoring BGRT: unexpected or invalid BMP data\n");
249 }
250 #else
251 static inline void efifb_show_boot_graphics(struct fb_info *info) {}
252 #endif
253 
254 static void efifb_destroy(struct fb_info *info)
255 {
256 	if (info->screen_base) {
257 		if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC))
258 			iounmap(info->screen_base);
259 		else
260 			memunmap(info->screen_base);
261 	}
262 	if (request_mem_succeeded)
263 		release_mem_region(info->apertures->ranges[0].base,
264 				   info->apertures->ranges[0].size);
265 	fb_dealloc_cmap(&info->cmap);
266 }
267 
268 static struct fb_ops efifb_ops = {
269 	.owner		= THIS_MODULE,
270 	.fb_destroy	= efifb_destroy,
271 	.fb_setcolreg	= efifb_setcolreg,
272 	.fb_fillrect	= cfb_fillrect,
273 	.fb_copyarea	= cfb_copyarea,
274 	.fb_imageblit	= cfb_imageblit,
275 };
276 
277 static int efifb_setup(char *options)
278 {
279 	char *this_opt;
280 
281 	if (options && *options) {
282 		while ((this_opt = strsep(&options, ",")) != NULL) {
283 			if (!*this_opt) continue;
284 
285 			efifb_setup_from_dmi(&screen_info, this_opt);
286 
287 			if (!strncmp(this_opt, "base:", 5))
288 				screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
289 			else if (!strncmp(this_opt, "stride:", 7))
290 				screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
291 			else if (!strncmp(this_opt, "height:", 7))
292 				screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
293 			else if (!strncmp(this_opt, "width:", 6))
294 				screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
295 			else if (!strcmp(this_opt, "nowc"))
296 				mem_flags &= ~EFI_MEMORY_WC;
297 			else if (!strcmp(this_opt, "nobgrt"))
298 				use_bgrt = false;
299 		}
300 	}
301 
302 	return 0;
303 }
304 
305 static inline bool fb_base_is_valid(void)
306 {
307 	if (screen_info.lfb_base)
308 		return true;
309 
310 	if (!(screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE))
311 		return false;
312 
313 	if (screen_info.ext_lfb_base)
314 		return true;
315 
316 	return false;
317 }
318 
319 #define efifb_attr_decl(name, fmt)					\
320 static ssize_t name##_show(struct device *dev,				\
321 			   struct device_attribute *attr,		\
322 			   char *buf)					\
323 {									\
324 	return sprintf(buf, fmt "\n", (screen_info.lfb_##name));	\
325 }									\
326 static DEVICE_ATTR_RO(name)
327 
328 efifb_attr_decl(base, "0x%x");
329 efifb_attr_decl(linelength, "%u");
330 efifb_attr_decl(height, "%u");
331 efifb_attr_decl(width, "%u");
332 efifb_attr_decl(depth, "%u");
333 
334 static struct attribute *efifb_attrs[] = {
335 	&dev_attr_base.attr,
336 	&dev_attr_linelength.attr,
337 	&dev_attr_width.attr,
338 	&dev_attr_height.attr,
339 	&dev_attr_depth.attr,
340 	NULL
341 };
342 ATTRIBUTE_GROUPS(efifb);
343 
344 static bool pci_dev_disabled;	/* FB base matches BAR of a disabled device */
345 
346 static struct pci_dev *efifb_pci_dev;	/* dev with BAR covering the efifb */
347 static struct resource *bar_resource;
348 static u64 bar_offset;
349 
350 static int efifb_probe(struct platform_device *dev)
351 {
352 	struct fb_info *info;
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 	if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI || pci_dev_disabled)
361 		return -ENODEV;
362 
363 	if (fb_get_options("efifb", &option))
364 		return -ENODEV;
365 	efifb_setup(option);
366 
367 	/* We don't get linelength from UGA Draw Protocol, only from
368 	 * EFI Graphics Protocol.  So if it's not in DMI, and it's not
369 	 * passed in from the user, we really can't use the framebuffer.
370 	 */
371 	if (!screen_info.lfb_linelength)
372 		return -ENODEV;
373 
374 	if (!screen_info.lfb_depth)
375 		screen_info.lfb_depth = 32;
376 	if (!screen_info.pages)
377 		screen_info.pages = 1;
378 	if (!fb_base_is_valid()) {
379 		printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
380 		return -ENODEV;
381 	}
382 	printk(KERN_INFO "efifb: probing for efifb\n");
383 
384 	/* just assume they're all unset if any are */
385 	if (!screen_info.blue_size) {
386 		screen_info.blue_size = 8;
387 		screen_info.blue_pos = 0;
388 		screen_info.green_size = 8;
389 		screen_info.green_pos = 8;
390 		screen_info.red_size = 8;
391 		screen_info.red_pos = 16;
392 		screen_info.rsvd_size = 8;
393 		screen_info.rsvd_pos = 24;
394 	}
395 
396 	efifb_fix.smem_start = screen_info.lfb_base;
397 
398 	if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) {
399 		u64 ext_lfb_base;
400 
401 		ext_lfb_base = (u64)(unsigned long)screen_info.ext_lfb_base << 32;
402 		efifb_fix.smem_start |= ext_lfb_base;
403 	}
404 
405 	if (bar_resource &&
406 	    bar_resource->start + bar_offset != efifb_fix.smem_start) {
407 		dev_info(&efifb_pci_dev->dev,
408 			 "BAR has moved, updating efifb address\n");
409 		efifb_fix.smem_start = bar_resource->start + bar_offset;
410 	}
411 
412 	efifb_defined.bits_per_pixel = screen_info.lfb_depth;
413 	efifb_defined.xres = screen_info.lfb_width;
414 	efifb_defined.yres = screen_info.lfb_height;
415 	efifb_fix.line_length = screen_info.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 = screen_info.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(u32) * 16, &dev->dev);
450 	if (!info) {
451 		pr_err("efifb: cannot allocate framebuffer\n");
452 		err = -ENOMEM;
453 		goto err_release_mem;
454 	}
455 	platform_set_drvdata(dev, info);
456 	info->pseudo_palette = info->par;
457 	info->par = NULL;
458 
459 	info->apertures = alloc_apertures(1);
460 	if (!info->apertures) {
461 		err = -ENOMEM;
462 		goto err_release_fb;
463 	}
464 	info->apertures->ranges[0].base = efifb_fix.smem_start;
465 	info->apertures->ranges[0].size = size_remap;
466 
467 	if (efi_enabled(EFI_BOOT) &&
468 	    !efi_mem_desc_lookup(efifb_fix.smem_start, &md)) {
469 		if ((efifb_fix.smem_start + efifb_fix.smem_len) >
470 		    (md.phys_addr + (md.num_pages << EFI_PAGE_SHIFT))) {
471 			pr_err("efifb: video memory @ 0x%lx spans multiple EFI memory regions\n",
472 			       efifb_fix.smem_start);
473 			err = -EIO;
474 			goto err_release_fb;
475 		}
476 		/*
477 		 * If the UEFI memory map covers the efifb region, we may only
478 		 * remap it using the attributes the memory map prescribes.
479 		 */
480 		md.attribute &= EFI_MEMORY_UC | EFI_MEMORY_WC |
481 				EFI_MEMORY_WT | EFI_MEMORY_WB;
482 		if (md.attribute) {
483 			mem_flags |= EFI_MEMORY_WT | EFI_MEMORY_WB;
484 			mem_flags &= md.attribute;
485 		}
486 	}
487 	if (mem_flags & EFI_MEMORY_WC)
488 		info->screen_base = ioremap_wc(efifb_fix.smem_start,
489 					       efifb_fix.smem_len);
490 	else if (mem_flags & EFI_MEMORY_UC)
491 		info->screen_base = ioremap(efifb_fix.smem_start,
492 					    efifb_fix.smem_len);
493 	else if (mem_flags & EFI_MEMORY_WT)
494 		info->screen_base = memremap(efifb_fix.smem_start,
495 					     efifb_fix.smem_len, MEMREMAP_WT);
496 	else if (mem_flags & EFI_MEMORY_WB)
497 		info->screen_base = memremap(efifb_fix.smem_start,
498 					     efifb_fix.smem_len, MEMREMAP_WB);
499 	if (!info->screen_base) {
500 		pr_err("efifb: abort, cannot remap video memory 0x%x @ 0x%lx\n",
501 			efifb_fix.smem_len, efifb_fix.smem_start);
502 		err = -EIO;
503 		goto err_release_fb;
504 	}
505 
506 	efifb_show_boot_graphics(info);
507 
508 	pr_info("efifb: framebuffer at 0x%lx, using %dk, total %dk\n",
509 	       efifb_fix.smem_start, size_remap/1024, size_total/1024);
510 	pr_info("efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
511 	       efifb_defined.xres, efifb_defined.yres,
512 	       efifb_defined.bits_per_pixel, efifb_fix.line_length,
513 	       screen_info.pages);
514 
515 	efifb_defined.xres_virtual = efifb_defined.xres;
516 	efifb_defined.yres_virtual = efifb_fix.smem_len /
517 					efifb_fix.line_length;
518 	pr_info("efifb: scrolling: redraw\n");
519 	efifb_defined.yres_virtual = efifb_defined.yres;
520 
521 	/* some dummy values for timing to make fbset happy */
522 	efifb_defined.pixclock     = 10000000 / efifb_defined.xres *
523 					1000 / efifb_defined.yres;
524 	efifb_defined.left_margin  = (efifb_defined.xres / 8) & 0xf8;
525 	efifb_defined.hsync_len    = (efifb_defined.xres / 8) & 0xf8;
526 
527 	efifb_defined.red.offset    = screen_info.red_pos;
528 	efifb_defined.red.length    = screen_info.red_size;
529 	efifb_defined.green.offset  = screen_info.green_pos;
530 	efifb_defined.green.length  = screen_info.green_size;
531 	efifb_defined.blue.offset   = screen_info.blue_pos;
532 	efifb_defined.blue.length   = screen_info.blue_size;
533 	efifb_defined.transp.offset = screen_info.rsvd_pos;
534 	efifb_defined.transp.length = screen_info.rsvd_size;
535 
536 	pr_info("efifb: %s: "
537 	       "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
538 	       "Truecolor",
539 	       screen_info.rsvd_size,
540 	       screen_info.red_size,
541 	       screen_info.green_size,
542 	       screen_info.blue_size,
543 	       screen_info.rsvd_pos,
544 	       screen_info.red_pos,
545 	       screen_info.green_pos,
546 	       screen_info.blue_pos);
547 
548 	efifb_fix.ypanstep  = 0;
549 	efifb_fix.ywrapstep = 0;
550 
551 	info->fbops = &efifb_ops;
552 	info->var = efifb_defined;
553 	info->fix = efifb_fix;
554 	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE;
555 
556 	orientation = drm_get_panel_orientation_quirk(efifb_defined.xres,
557 						      efifb_defined.yres);
558 	switch (orientation) {
559 	default:
560 		info->fbcon_rotate_hint = FB_ROTATE_UR;
561 		break;
562 	case DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP:
563 		info->fbcon_rotate_hint = FB_ROTATE_UD;
564 		break;
565 	case DRM_MODE_PANEL_ORIENTATION_LEFT_UP:
566 		info->fbcon_rotate_hint = FB_ROTATE_CCW;
567 		break;
568 	case DRM_MODE_PANEL_ORIENTATION_RIGHT_UP:
569 		info->fbcon_rotate_hint = FB_ROTATE_CW;
570 		break;
571 	}
572 
573 	err = sysfs_create_groups(&dev->dev.kobj, efifb_groups);
574 	if (err) {
575 		pr_err("efifb: cannot add sysfs attrs\n");
576 		goto err_unmap;
577 	}
578 	err = fb_alloc_cmap(&info->cmap, 256, 0);
579 	if (err < 0) {
580 		pr_err("efifb: cannot allocate colormap\n");
581 		goto err_groups;
582 	}
583 	err = register_framebuffer(info);
584 	if (err < 0) {
585 		pr_err("efifb: cannot register framebuffer\n");
586 		goto err_fb_dealoc;
587 	}
588 	fb_info(info, "%s frame buffer device\n", info->fix.id);
589 	return 0;
590 
591 err_fb_dealoc:
592 	fb_dealloc_cmap(&info->cmap);
593 err_groups:
594 	sysfs_remove_groups(&dev->dev.kobj, efifb_groups);
595 err_unmap:
596 	if (mem_flags & (EFI_MEMORY_UC | EFI_MEMORY_WC))
597 		iounmap(info->screen_base);
598 	else
599 		memunmap(info->screen_base);
600 err_release_fb:
601 	framebuffer_release(info);
602 err_release_mem:
603 	if (request_mem_succeeded)
604 		release_mem_region(efifb_fix.smem_start, size_total);
605 	return err;
606 }
607 
608 static int efifb_remove(struct platform_device *pdev)
609 {
610 	struct fb_info *info = platform_get_drvdata(pdev);
611 
612 	unregister_framebuffer(info);
613 	sysfs_remove_groups(&pdev->dev.kobj, efifb_groups);
614 	framebuffer_release(info);
615 
616 	return 0;
617 }
618 
619 static struct platform_driver efifb_driver = {
620 	.driver = {
621 		.name = "efi-framebuffer",
622 	},
623 	.probe = efifb_probe,
624 	.remove = efifb_remove,
625 };
626 
627 builtin_platform_driver(efifb_driver);
628 
629 #if defined(CONFIG_PCI)
630 
631 static void record_efifb_bar_resource(struct pci_dev *dev, int idx, u64 offset)
632 {
633 	u16 word;
634 
635 	efifb_pci_dev = dev;
636 
637 	pci_read_config_word(dev, PCI_COMMAND, &word);
638 	if (!(word & PCI_COMMAND_MEMORY)) {
639 		pci_dev_disabled = true;
640 		dev_err(&dev->dev,
641 			"BAR %d: assigned to efifb but device is disabled!\n",
642 			idx);
643 		return;
644 	}
645 
646 	bar_resource = &dev->resource[idx];
647 	bar_offset = offset;
648 
649 	dev_info(&dev->dev, "BAR %d: assigned to efifb\n", idx);
650 }
651 
652 static void efifb_fixup_resources(struct pci_dev *dev)
653 {
654 	u64 base = screen_info.lfb_base;
655 	u64 size = screen_info.lfb_size;
656 	int i;
657 
658 	if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
659 		return;
660 
661 	if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
662 		base |= (u64)screen_info.ext_lfb_base << 32;
663 
664 	if (!base)
665 		return;
666 
667 	for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
668 		struct resource *res = &dev->resource[i];
669 
670 		if (!(res->flags & IORESOURCE_MEM))
671 			continue;
672 
673 		if (res->start <= base && res->end >= base + size - 1) {
674 			record_efifb_bar_resource(dev, i, base - res->start);
675 			break;
676 		}
677 	}
678 }
679 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY,
680 			       16, efifb_fixup_resources);
681 
682 #endif
683