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
20static bool request_mem_succeeded = false;
21
22static 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
33static 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
40static 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
66static 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
76static 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
85static 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
117static int efifb_probe(struct platform_device *dev)
118{
119	struct fb_info *info;
120	int err;
121	unsigned int size_vmode;
122	unsigned int size_remap;
123	unsigned int size_total;
124	char *option = NULL;
125
126	if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
127		return -ENODEV;
128
129	if (fb_get_options("efifb", &option))
130		return -ENODEV;
131	efifb_setup(option);
132
133	/* We don't get linelength from UGA Draw Protocol, only from
134	 * EFI Graphics Protocol.  So if it's not in DMI, and it's not
135	 * passed in from the user, we really can't use the framebuffer.
136	 */
137	if (!screen_info.lfb_linelength)
138		return -ENODEV;
139
140	if (!screen_info.lfb_depth)
141		screen_info.lfb_depth = 32;
142	if (!screen_info.pages)
143		screen_info.pages = 1;
144	if (!screen_info.lfb_base) {
145		printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
146		return -ENODEV;
147	}
148	printk(KERN_INFO "efifb: probing for efifb\n");
149
150	/* just assume they're all unset if any are */
151	if (!screen_info.blue_size) {
152		screen_info.blue_size = 8;
153		screen_info.blue_pos = 0;
154		screen_info.green_size = 8;
155		screen_info.green_pos = 8;
156		screen_info.red_size = 8;
157		screen_info.red_pos = 16;
158		screen_info.rsvd_size = 8;
159		screen_info.rsvd_pos = 24;
160	}
161
162	efifb_fix.smem_start = screen_info.lfb_base;
163	efifb_defined.bits_per_pixel = screen_info.lfb_depth;
164	efifb_defined.xres = screen_info.lfb_width;
165	efifb_defined.yres = screen_info.lfb_height;
166	efifb_fix.line_length = screen_info.lfb_linelength;
167
168	/*   size_vmode -- that is the amount of memory needed for the
169	 *                 used video mode, i.e. the minimum amount of
170	 *                 memory we need. */
171	size_vmode = efifb_defined.yres * efifb_fix.line_length;
172
173	/*   size_total -- all video memory we have. Used for
174	 *                 entries, ressource allocation and bounds
175	 *                 checking. */
176	size_total = screen_info.lfb_size;
177	if (size_total < size_vmode)
178		size_total = size_vmode;
179
180	/*   size_remap -- the amount of video memory we are going to
181	 *                 use for efifb.  With modern cards it is no
182	 *                 option to simply use size_total as that
183	 *                 wastes plenty of kernel address space. */
184	size_remap  = size_vmode * 2;
185	if (size_remap > size_total)
186		size_remap = size_total;
187	if (size_remap % PAGE_SIZE)
188		size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
189	efifb_fix.smem_len = size_remap;
190
191	if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
192		request_mem_succeeded = true;
193	} else {
194		/* We cannot make this fatal. Sometimes this comes from magic
195		   spaces our resource handlers simply don't know about */
196		printk(KERN_WARNING
197		       "efifb: cannot reserve video memory at 0x%lx\n",
198			efifb_fix.smem_start);
199	}
200
201	info = framebuffer_alloc(sizeof(u32) * 16, &dev->dev);
202	if (!info) {
203		printk(KERN_ERR "efifb: cannot allocate framebuffer\n");
204		err = -ENOMEM;
205		goto err_release_mem;
206	}
207	platform_set_drvdata(dev, info);
208	info->pseudo_palette = info->par;
209	info->par = NULL;
210
211	info->apertures = alloc_apertures(1);
212	if (!info->apertures) {
213		err = -ENOMEM;
214		goto err_release_fb;
215	}
216	info->apertures->ranges[0].base = efifb_fix.smem_start;
217	info->apertures->ranges[0].size = size_remap;
218
219	info->screen_base = ioremap_wc(efifb_fix.smem_start, efifb_fix.smem_len);
220	if (!info->screen_base) {
221		printk(KERN_ERR "efifb: abort, cannot ioremap video memory "
222				"0x%x @ 0x%lx\n",
223			efifb_fix.smem_len, efifb_fix.smem_start);
224		err = -EIO;
225		goto err_release_fb;
226	}
227
228	printk(KERN_INFO "efifb: framebuffer at 0x%lx, mapped to 0x%p, "
229	       "using %dk, total %dk\n",
230	       efifb_fix.smem_start, info->screen_base,
231	       size_remap/1024, size_total/1024);
232	printk(KERN_INFO "efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
233	       efifb_defined.xres, efifb_defined.yres,
234	       efifb_defined.bits_per_pixel, efifb_fix.line_length,
235	       screen_info.pages);
236
237	efifb_defined.xres_virtual = efifb_defined.xres;
238	efifb_defined.yres_virtual = efifb_fix.smem_len /
239					efifb_fix.line_length;
240	printk(KERN_INFO "efifb: scrolling: redraw\n");
241	efifb_defined.yres_virtual = efifb_defined.yres;
242
243	/* some dummy values for timing to make fbset happy */
244	efifb_defined.pixclock     = 10000000 / efifb_defined.xres *
245					1000 / efifb_defined.yres;
246	efifb_defined.left_margin  = (efifb_defined.xres / 8) & 0xf8;
247	efifb_defined.hsync_len    = (efifb_defined.xres / 8) & 0xf8;
248
249	efifb_defined.red.offset    = screen_info.red_pos;
250	efifb_defined.red.length    = screen_info.red_size;
251	efifb_defined.green.offset  = screen_info.green_pos;
252	efifb_defined.green.length  = screen_info.green_size;
253	efifb_defined.blue.offset   = screen_info.blue_pos;
254	efifb_defined.blue.length   = screen_info.blue_size;
255	efifb_defined.transp.offset = screen_info.rsvd_pos;
256	efifb_defined.transp.length = screen_info.rsvd_size;
257
258	printk(KERN_INFO "efifb: %s: "
259	       "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
260	       "Truecolor",
261	       screen_info.rsvd_size,
262	       screen_info.red_size,
263	       screen_info.green_size,
264	       screen_info.blue_size,
265	       screen_info.rsvd_pos,
266	       screen_info.red_pos,
267	       screen_info.green_pos,
268	       screen_info.blue_pos);
269
270	efifb_fix.ypanstep  = 0;
271	efifb_fix.ywrapstep = 0;
272
273	info->fbops = &efifb_ops;
274	info->var = efifb_defined;
275	info->fix = efifb_fix;
276	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE;
277
278	if ((err = fb_alloc_cmap(&info->cmap, 256, 0)) < 0) {
279		printk(KERN_ERR "efifb: cannot allocate colormap\n");
280		goto err_unmap;
281	}
282	if ((err = register_framebuffer(info)) < 0) {
283		printk(KERN_ERR "efifb: cannot register framebuffer\n");
284		goto err_fb_dealoc;
285	}
286	fb_info(info, "%s frame buffer device\n", info->fix.id);
287	return 0;
288
289err_fb_dealoc:
290	fb_dealloc_cmap(&info->cmap);
291err_unmap:
292	iounmap(info->screen_base);
293err_release_fb:
294	framebuffer_release(info);
295err_release_mem:
296	if (request_mem_succeeded)
297		release_mem_region(efifb_fix.smem_start, size_total);
298	return err;
299}
300
301static int efifb_remove(struct platform_device *pdev)
302{
303	struct fb_info *info = platform_get_drvdata(pdev);
304
305	unregister_framebuffer(info);
306	framebuffer_release(info);
307
308	return 0;
309}
310
311static struct platform_driver efifb_driver = {
312	.driver = {
313		.name = "efi-framebuffer",
314	},
315	.probe = efifb_probe,
316	.remove = efifb_remove,
317};
318
319module_platform_driver(efifb_driver);
320MODULE_LICENSE("GPL");
321