xref: /openbmc/linux/drivers/video/fbdev/efifb.c (revision 0f4630f3)
1 /*
2  * Framebuffer driver for EFI/UEFI based system
3  *
4  * (c) 2006 Edgar Hucek <gimli@dark-green.com>
5  * Original efi driver written by Gerd Knorr <kraxel@goldbach.in-berlin.de>
6  *
7  */
8 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/errno.h>
12 #include <linux/fb.h>
13 #include <linux/platform_device.h>
14 #include <linux/screen_info.h>
15 #include <linux/dmi.h>
16 #include <linux/pci.h>
17 #include <video/vga.h>
18 #include <asm/sysfb.h>
19 
20 static bool request_mem_succeeded = false;
21 
22 static struct fb_var_screeninfo efifb_defined = {
23 	.activate		= FB_ACTIVATE_NOW,
24 	.height			= -1,
25 	.width			= -1,
26 	.right_margin		= 32,
27 	.upper_margin		= 16,
28 	.lower_margin		= 4,
29 	.vsync_len		= 4,
30 	.vmode			= FB_VMODE_NONINTERLACED,
31 };
32 
33 static struct fb_fix_screeninfo efifb_fix = {
34 	.id			= "EFI VGA",
35 	.type			= FB_TYPE_PACKED_PIXELS,
36 	.accel			= FB_ACCEL_NONE,
37 	.visual			= FB_VISUAL_TRUECOLOR,
38 };
39 
40 static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
41 			   unsigned blue, unsigned transp,
42 			   struct fb_info *info)
43 {
44 	/*
45 	 *  Set a single color register. The values supplied are
46 	 *  already rounded down to the hardware's capabilities
47 	 *  (according to the entries in the `var' structure). Return
48 	 *  != 0 for invalid regno.
49 	 */
50 
51 	if (regno >= info->cmap.len)
52 		return 1;
53 
54 	if (regno < 16) {
55 		red   >>= 8;
56 		green >>= 8;
57 		blue  >>= 8;
58 		((u32 *)(info->pseudo_palette))[regno] =
59 			(red   << info->var.red.offset)   |
60 			(green << info->var.green.offset) |
61 			(blue  << info->var.blue.offset);
62 	}
63 	return 0;
64 }
65 
66 static void efifb_destroy(struct fb_info *info)
67 {
68 	if (info->screen_base)
69 		iounmap(info->screen_base);
70 	if (request_mem_succeeded)
71 		release_mem_region(info->apertures->ranges[0].base,
72 				   info->apertures->ranges[0].size);
73 	fb_dealloc_cmap(&info->cmap);
74 }
75 
76 static struct fb_ops efifb_ops = {
77 	.owner		= THIS_MODULE,
78 	.fb_destroy	= efifb_destroy,
79 	.fb_setcolreg	= efifb_setcolreg,
80 	.fb_fillrect	= cfb_fillrect,
81 	.fb_copyarea	= cfb_copyarea,
82 	.fb_imageblit	= cfb_imageblit,
83 };
84 
85 static int efifb_setup(char *options)
86 {
87 	char *this_opt;
88 	int i;
89 
90 	if (options && *options) {
91 		while ((this_opt = strsep(&options, ",")) != NULL) {
92 			if (!*this_opt) continue;
93 
94 			for (i = 0; i < M_UNKNOWN; i++) {
95 				if (efifb_dmi_list[i].base != 0 &&
96 				    !strcmp(this_opt, efifb_dmi_list[i].optname)) {
97 					screen_info.lfb_base = efifb_dmi_list[i].base;
98 					screen_info.lfb_linelength = efifb_dmi_list[i].stride;
99 					screen_info.lfb_width = efifb_dmi_list[i].width;
100 					screen_info.lfb_height = efifb_dmi_list[i].height;
101 				}
102 			}
103 			if (!strncmp(this_opt, "base:", 5))
104 				screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
105 			else if (!strncmp(this_opt, "stride:", 7))
106 				screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
107 			else if (!strncmp(this_opt, "height:", 7))
108 				screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
109 			else if (!strncmp(this_opt, "width:", 6))
110 				screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
111 		}
112 	}
113 
114 	return 0;
115 }
116 
117 static inline bool fb_base_is_valid(void)
118 {
119 	if (screen_info.lfb_base)
120 		return true;
121 
122 	if (!(screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE))
123 		return false;
124 
125 	if (screen_info.ext_lfb_base)
126 		return true;
127 
128 	return false;
129 }
130 
131 static int efifb_probe(struct platform_device *dev)
132 {
133 	struct fb_info *info;
134 	int err;
135 	unsigned int size_vmode;
136 	unsigned int size_remap;
137 	unsigned int size_total;
138 	char *option = NULL;
139 
140 	if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
141 		return -ENODEV;
142 
143 	if (fb_get_options("efifb", &option))
144 		return -ENODEV;
145 	efifb_setup(option);
146 
147 	/* We don't get linelength from UGA Draw Protocol, only from
148 	 * EFI Graphics Protocol.  So if it's not in DMI, and it's not
149 	 * passed in from the user, we really can't use the framebuffer.
150 	 */
151 	if (!screen_info.lfb_linelength)
152 		return -ENODEV;
153 
154 	if (!screen_info.lfb_depth)
155 		screen_info.lfb_depth = 32;
156 	if (!screen_info.pages)
157 		screen_info.pages = 1;
158 	if (!fb_base_is_valid()) {
159 		printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
160 		return -ENODEV;
161 	}
162 	printk(KERN_INFO "efifb: probing for efifb\n");
163 
164 	/* just assume they're all unset if any are */
165 	if (!screen_info.blue_size) {
166 		screen_info.blue_size = 8;
167 		screen_info.blue_pos = 0;
168 		screen_info.green_size = 8;
169 		screen_info.green_pos = 8;
170 		screen_info.red_size = 8;
171 		screen_info.red_pos = 16;
172 		screen_info.rsvd_size = 8;
173 		screen_info.rsvd_pos = 24;
174 	}
175 
176 	efifb_fix.smem_start = screen_info.lfb_base;
177 
178 	if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) {
179 		u64 ext_lfb_base;
180 
181 		ext_lfb_base = (u64)(unsigned long)screen_info.ext_lfb_base << 32;
182 		efifb_fix.smem_start |= ext_lfb_base;
183 	}
184 
185 	efifb_defined.bits_per_pixel = screen_info.lfb_depth;
186 	efifb_defined.xres = screen_info.lfb_width;
187 	efifb_defined.yres = screen_info.lfb_height;
188 	efifb_fix.line_length = screen_info.lfb_linelength;
189 
190 	/*   size_vmode -- that is the amount of memory needed for the
191 	 *                 used video mode, i.e. the minimum amount of
192 	 *                 memory we need. */
193 	size_vmode = efifb_defined.yres * efifb_fix.line_length;
194 
195 	/*   size_total -- all video memory we have. Used for
196 	 *                 entries, ressource allocation and bounds
197 	 *                 checking. */
198 	size_total = screen_info.lfb_size;
199 	if (size_total < size_vmode)
200 		size_total = size_vmode;
201 
202 	/*   size_remap -- the amount of video memory we are going to
203 	 *                 use for efifb.  With modern cards it is no
204 	 *                 option to simply use size_total as that
205 	 *                 wastes plenty of kernel address space. */
206 	size_remap  = size_vmode * 2;
207 	if (size_remap > size_total)
208 		size_remap = size_total;
209 	if (size_remap % PAGE_SIZE)
210 		size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
211 	efifb_fix.smem_len = size_remap;
212 
213 	if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
214 		request_mem_succeeded = true;
215 	} else {
216 		/* We cannot make this fatal. Sometimes this comes from magic
217 		   spaces our resource handlers simply don't know about */
218 		printk(KERN_WARNING
219 		       "efifb: cannot reserve video memory at 0x%lx\n",
220 			efifb_fix.smem_start);
221 	}
222 
223 	info = framebuffer_alloc(sizeof(u32) * 16, &dev->dev);
224 	if (!info) {
225 		printk(KERN_ERR "efifb: cannot allocate framebuffer\n");
226 		err = -ENOMEM;
227 		goto err_release_mem;
228 	}
229 	platform_set_drvdata(dev, info);
230 	info->pseudo_palette = info->par;
231 	info->par = NULL;
232 
233 	info->apertures = alloc_apertures(1);
234 	if (!info->apertures) {
235 		err = -ENOMEM;
236 		goto err_release_fb;
237 	}
238 	info->apertures->ranges[0].base = efifb_fix.smem_start;
239 	info->apertures->ranges[0].size = size_remap;
240 
241 	info->screen_base = ioremap_wc(efifb_fix.smem_start, efifb_fix.smem_len);
242 	if (!info->screen_base) {
243 		printk(KERN_ERR "efifb: abort, cannot ioremap video memory "
244 				"0x%x @ 0x%lx\n",
245 			efifb_fix.smem_len, efifb_fix.smem_start);
246 		err = -EIO;
247 		goto err_release_fb;
248 	}
249 
250 	printk(KERN_INFO "efifb: framebuffer at 0x%lx, mapped to 0x%p, "
251 	       "using %dk, total %dk\n",
252 	       efifb_fix.smem_start, info->screen_base,
253 	       size_remap/1024, size_total/1024);
254 	printk(KERN_INFO "efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
255 	       efifb_defined.xres, efifb_defined.yres,
256 	       efifb_defined.bits_per_pixel, efifb_fix.line_length,
257 	       screen_info.pages);
258 
259 	efifb_defined.xres_virtual = efifb_defined.xres;
260 	efifb_defined.yres_virtual = efifb_fix.smem_len /
261 					efifb_fix.line_length;
262 	printk(KERN_INFO "efifb: scrolling: redraw\n");
263 	efifb_defined.yres_virtual = efifb_defined.yres;
264 
265 	/* some dummy values for timing to make fbset happy */
266 	efifb_defined.pixclock     = 10000000 / efifb_defined.xres *
267 					1000 / efifb_defined.yres;
268 	efifb_defined.left_margin  = (efifb_defined.xres / 8) & 0xf8;
269 	efifb_defined.hsync_len    = (efifb_defined.xres / 8) & 0xf8;
270 
271 	efifb_defined.red.offset    = screen_info.red_pos;
272 	efifb_defined.red.length    = screen_info.red_size;
273 	efifb_defined.green.offset  = screen_info.green_pos;
274 	efifb_defined.green.length  = screen_info.green_size;
275 	efifb_defined.blue.offset   = screen_info.blue_pos;
276 	efifb_defined.blue.length   = screen_info.blue_size;
277 	efifb_defined.transp.offset = screen_info.rsvd_pos;
278 	efifb_defined.transp.length = screen_info.rsvd_size;
279 
280 	printk(KERN_INFO "efifb: %s: "
281 	       "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
282 	       "Truecolor",
283 	       screen_info.rsvd_size,
284 	       screen_info.red_size,
285 	       screen_info.green_size,
286 	       screen_info.blue_size,
287 	       screen_info.rsvd_pos,
288 	       screen_info.red_pos,
289 	       screen_info.green_pos,
290 	       screen_info.blue_pos);
291 
292 	efifb_fix.ypanstep  = 0;
293 	efifb_fix.ywrapstep = 0;
294 
295 	info->fbops = &efifb_ops;
296 	info->var = efifb_defined;
297 	info->fix = efifb_fix;
298 	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE;
299 
300 	if ((err = fb_alloc_cmap(&info->cmap, 256, 0)) < 0) {
301 		printk(KERN_ERR "efifb: cannot allocate colormap\n");
302 		goto err_unmap;
303 	}
304 	if ((err = register_framebuffer(info)) < 0) {
305 		printk(KERN_ERR "efifb: cannot register framebuffer\n");
306 		goto err_fb_dealoc;
307 	}
308 	fb_info(info, "%s frame buffer device\n", info->fix.id);
309 	return 0;
310 
311 err_fb_dealoc:
312 	fb_dealloc_cmap(&info->cmap);
313 err_unmap:
314 	iounmap(info->screen_base);
315 err_release_fb:
316 	framebuffer_release(info);
317 err_release_mem:
318 	if (request_mem_succeeded)
319 		release_mem_region(efifb_fix.smem_start, size_total);
320 	return err;
321 }
322 
323 static int efifb_remove(struct platform_device *pdev)
324 {
325 	struct fb_info *info = platform_get_drvdata(pdev);
326 
327 	unregister_framebuffer(info);
328 	framebuffer_release(info);
329 
330 	return 0;
331 }
332 
333 static struct platform_driver efifb_driver = {
334 	.driver = {
335 		.name = "efi-framebuffer",
336 	},
337 	.probe = efifb_probe,
338 	.remove = efifb_remove,
339 };
340 
341 module_platform_driver(efifb_driver);
342 MODULE_LICENSE("GPL");
343