1 // SPDX-License-Identifier: GPL-2.0
3 * Framebuffer driver for EFI/UEFI based system
5 * (c) 2006 Edgar Hucek <gimli@dark-green.com>
6 * Original efi driver written by Gerd Knorr <kraxel@goldbach.in-berlin.de>
10 #include <linux/kernel.h>
11 #include <linux/efi.h>
12 #include <linux/errno.h>
14 #include <linux/pci.h>
15 #include <linux/platform_device.h>
16 #include <linux/screen_info.h>
17 #include <video/vga.h>
20 static bool request_mem_succeeded = false;
21 static bool nowc = false;
23 static struct fb_var_screeninfo efifb_defined = {
24 .activate = FB_ACTIVATE_NOW,
31 .vmode = FB_VMODE_NONINTERLACED,
34 static struct fb_fix_screeninfo efifb_fix = {
36 .type = FB_TYPE_PACKED_PIXELS,
37 .accel = FB_ACCEL_NONE,
38 .visual = FB_VISUAL_TRUECOLOR,
41 static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
42 unsigned blue, unsigned transp,
46 * Set a single color register. The values supplied are
47 * already rounded down to the hardware's capabilities
48 * (according to the entries in the `var' structure). Return
49 * != 0 for invalid regno.
52 if (regno >= info->cmap.len)
56 red >>= 16 - info->var.red.length;
57 green >>= 16 - info->var.green.length;
58 blue >>= 16 - info->var.blue.length;
59 ((u32 *)(info->pseudo_palette))[regno] =
60 (red << info->var.red.offset) |
61 (green << info->var.green.offset) |
62 (blue << info->var.blue.offset);
67 static void efifb_destroy(struct fb_info *info)
69 if (info->screen_base)
70 iounmap(info->screen_base);
71 if (request_mem_succeeded)
72 release_mem_region(info->apertures->ranges[0].base,
73 info->apertures->ranges[0].size);
74 fb_dealloc_cmap(&info->cmap);
77 static struct fb_ops efifb_ops = {
79 .fb_destroy = efifb_destroy,
80 .fb_setcolreg = efifb_setcolreg,
81 .fb_fillrect = cfb_fillrect,
82 .fb_copyarea = cfb_copyarea,
83 .fb_imageblit = cfb_imageblit,
86 static int efifb_setup(char *options)
90 if (options && *options) {
91 while ((this_opt = strsep(&options, ",")) != NULL) {
92 if (!*this_opt) continue;
94 efifb_setup_from_dmi(&screen_info, this_opt);
96 if (!strncmp(this_opt, "base:", 5))
97 screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
98 else if (!strncmp(this_opt, "stride:", 7))
99 screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
100 else if (!strncmp(this_opt, "height:", 7))
101 screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
102 else if (!strncmp(this_opt, "width:", 6))
103 screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
104 else if (!strcmp(this_opt, "nowc"))
112 static inline bool fb_base_is_valid(void)
114 if (screen_info.lfb_base)
117 if (!(screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE))
120 if (screen_info.ext_lfb_base)
126 #define efifb_attr_decl(name, fmt) \
127 static ssize_t name##_show(struct device *dev, \
128 struct device_attribute *attr, \
131 return sprintf(buf, fmt "\n", (screen_info.lfb_##name)); \
133 static DEVICE_ATTR_RO(name)
135 efifb_attr_decl(base, "0x%x");
136 efifb_attr_decl(linelength, "%u");
137 efifb_attr_decl(height, "%u");
138 efifb_attr_decl(width, "%u");
139 efifb_attr_decl(depth, "%u");
141 static struct attribute *efifb_attrs[] = {
143 &dev_attr_linelength.attr,
144 &dev_attr_width.attr,
145 &dev_attr_height.attr,
146 &dev_attr_depth.attr,
149 ATTRIBUTE_GROUPS(efifb);
151 static bool pci_dev_disabled; /* FB base matches BAR of a disabled device */
153 static struct pci_dev *efifb_pci_dev; /* dev with BAR covering the efifb */
154 static struct resource *bar_resource;
155 static u64 bar_offset;
157 static int efifb_probe(struct platform_device *dev)
159 struct fb_info *info;
161 unsigned int size_vmode;
162 unsigned int size_remap;
163 unsigned int size_total;
166 if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI || pci_dev_disabled)
169 if (fb_get_options("efifb", &option))
173 /* We don't get linelength from UGA Draw Protocol, only from
174 * EFI Graphics Protocol. So if it's not in DMI, and it's not
175 * passed in from the user, we really can't use the framebuffer.
177 if (!screen_info.lfb_linelength)
180 if (!screen_info.lfb_depth)
181 screen_info.lfb_depth = 32;
182 if (!screen_info.pages)
183 screen_info.pages = 1;
184 if (!fb_base_is_valid()) {
185 printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
188 printk(KERN_INFO "efifb: probing for efifb\n");
190 /* just assume they're all unset if any are */
191 if (!screen_info.blue_size) {
192 screen_info.blue_size = 8;
193 screen_info.blue_pos = 0;
194 screen_info.green_size = 8;
195 screen_info.green_pos = 8;
196 screen_info.red_size = 8;
197 screen_info.red_pos = 16;
198 screen_info.rsvd_size = 8;
199 screen_info.rsvd_pos = 24;
202 efifb_fix.smem_start = screen_info.lfb_base;
204 if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) {
207 ext_lfb_base = (u64)(unsigned long)screen_info.ext_lfb_base << 32;
208 efifb_fix.smem_start |= ext_lfb_base;
212 bar_resource->start + bar_offset != efifb_fix.smem_start) {
213 dev_info(&efifb_pci_dev->dev,
214 "BAR has moved, updating efifb address\n");
215 efifb_fix.smem_start = bar_resource->start + bar_offset;
218 efifb_defined.bits_per_pixel = screen_info.lfb_depth;
219 efifb_defined.xres = screen_info.lfb_width;
220 efifb_defined.yres = screen_info.lfb_height;
221 efifb_fix.line_length = screen_info.lfb_linelength;
223 /* size_vmode -- that is the amount of memory needed for the
224 * used video mode, i.e. the minimum amount of
226 size_vmode = efifb_defined.yres * efifb_fix.line_length;
228 /* size_total -- all video memory we have. Used for
229 * entries, ressource allocation and bounds
231 size_total = screen_info.lfb_size;
232 if (size_total < size_vmode)
233 size_total = size_vmode;
235 /* size_remap -- the amount of video memory we are going to
236 * use for efifb. With modern cards it is no
237 * option to simply use size_total as that
238 * wastes plenty of kernel address space. */
239 size_remap = size_vmode * 2;
240 if (size_remap > size_total)
241 size_remap = size_total;
242 if (size_remap % PAGE_SIZE)
243 size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
244 efifb_fix.smem_len = size_remap;
246 if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
247 request_mem_succeeded = true;
249 /* We cannot make this fatal. Sometimes this comes from magic
250 spaces our resource handlers simply don't know about */
251 pr_warn("efifb: cannot reserve video memory at 0x%lx\n",
252 efifb_fix.smem_start);
255 info = framebuffer_alloc(sizeof(u32) * 16, &dev->dev);
257 pr_err("efifb: cannot allocate framebuffer\n");
259 goto err_release_mem;
261 platform_set_drvdata(dev, info);
262 info->pseudo_palette = info->par;
265 info->apertures = alloc_apertures(1);
266 if (!info->apertures) {
270 info->apertures->ranges[0].base = efifb_fix.smem_start;
271 info->apertures->ranges[0].size = size_remap;
274 info->screen_base = ioremap(efifb_fix.smem_start, efifb_fix.smem_len);
276 info->screen_base = ioremap_wc(efifb_fix.smem_start, efifb_fix.smem_len);
277 if (!info->screen_base) {
278 pr_err("efifb: abort, cannot ioremap video memory 0x%x @ 0x%lx\n",
279 efifb_fix.smem_len, efifb_fix.smem_start);
284 pr_info("efifb: framebuffer at 0x%lx, using %dk, total %dk\n",
285 efifb_fix.smem_start, size_remap/1024, size_total/1024);
286 pr_info("efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
287 efifb_defined.xres, efifb_defined.yres,
288 efifb_defined.bits_per_pixel, efifb_fix.line_length,
291 efifb_defined.xres_virtual = efifb_defined.xres;
292 efifb_defined.yres_virtual = efifb_fix.smem_len /
293 efifb_fix.line_length;
294 pr_info("efifb: scrolling: redraw\n");
295 efifb_defined.yres_virtual = efifb_defined.yres;
297 /* some dummy values for timing to make fbset happy */
298 efifb_defined.pixclock = 10000000 / efifb_defined.xres *
299 1000 / efifb_defined.yres;
300 efifb_defined.left_margin = (efifb_defined.xres / 8) & 0xf8;
301 efifb_defined.hsync_len = (efifb_defined.xres / 8) & 0xf8;
303 efifb_defined.red.offset = screen_info.red_pos;
304 efifb_defined.red.length = screen_info.red_size;
305 efifb_defined.green.offset = screen_info.green_pos;
306 efifb_defined.green.length = screen_info.green_size;
307 efifb_defined.blue.offset = screen_info.blue_pos;
308 efifb_defined.blue.length = screen_info.blue_size;
309 efifb_defined.transp.offset = screen_info.rsvd_pos;
310 efifb_defined.transp.length = screen_info.rsvd_size;
312 pr_info("efifb: %s: "
313 "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
315 screen_info.rsvd_size,
316 screen_info.red_size,
317 screen_info.green_size,
318 screen_info.blue_size,
319 screen_info.rsvd_pos,
321 screen_info.green_pos,
322 screen_info.blue_pos);
324 efifb_fix.ypanstep = 0;
325 efifb_fix.ywrapstep = 0;
327 info->fbops = &efifb_ops;
328 info->var = efifb_defined;
329 info->fix = efifb_fix;
330 info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE;
332 err = sysfs_create_groups(&dev->dev.kobj, efifb_groups);
334 pr_err("efifb: cannot add sysfs attrs\n");
337 err = fb_alloc_cmap(&info->cmap, 256, 0);
339 pr_err("efifb: cannot allocate colormap\n");
342 err = register_framebuffer(info);
344 pr_err("efifb: cannot register framebuffer\n");
347 fb_info(info, "%s frame buffer device\n", info->fix.id);
351 fb_dealloc_cmap(&info->cmap);
353 sysfs_remove_groups(&dev->dev.kobj, efifb_groups);
355 iounmap(info->screen_base);
357 framebuffer_release(info);
359 if (request_mem_succeeded)
360 release_mem_region(efifb_fix.smem_start, size_total);
364 static int efifb_remove(struct platform_device *pdev)
366 struct fb_info *info = platform_get_drvdata(pdev);
368 unregister_framebuffer(info);
369 sysfs_remove_groups(&pdev->dev.kobj, efifb_groups);
370 framebuffer_release(info);
375 static struct platform_driver efifb_driver = {
377 .name = "efi-framebuffer",
379 .probe = efifb_probe,
380 .remove = efifb_remove,
383 builtin_platform_driver(efifb_driver);
385 #if defined(CONFIG_PCI)
387 static void record_efifb_bar_resource(struct pci_dev *dev, int idx, u64 offset)
393 pci_read_config_word(dev, PCI_COMMAND, &word);
394 if (!(word & PCI_COMMAND_MEMORY)) {
395 pci_dev_disabled = true;
397 "BAR %d: assigned to efifb but device is disabled!\n",
402 bar_resource = &dev->resource[idx];
405 dev_info(&dev->dev, "BAR %d: assigned to efifb\n", idx);
408 static void efifb_fixup_resources(struct pci_dev *dev)
410 u64 base = screen_info.lfb_base;
411 u64 size = screen_info.lfb_size;
414 if (efifb_pci_dev || screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
417 if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
418 base |= (u64)screen_info.ext_lfb_base << 32;
423 for (i = 0; i <= PCI_STD_RESOURCE_END; i++) {
424 struct resource *res = &dev->resource[i];
426 if (!(res->flags & IORESOURCE_MEM))
429 if (res->start <= base && res->end >= base + size - 1) {
430 record_efifb_bar_resource(dev, i, base - res->start);
435 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID, PCI_BASE_CLASS_DISPLAY,
436 16, efifb_fixup_resources);