xref: /openbmc/u-boot/drivers/video/efi.c (revision da4cfa6b)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
4  *
5  * EFI framebuffer driver based on GOP
6  */
7 
8 #include <common.h>
9 #include <dm.h>
10 #include <efi_api.h>
11 #include <vbe.h>
12 #include <video.h>
13 
14 struct pixel {
15 	u8 pos;
16 	u8 size;
17 };
18 
19 static const struct efi_framebuffer {
20 	struct pixel red;
21 	struct pixel green;
22 	struct pixel blue;
23 	struct pixel rsvd;
24 } efi_framebuffer_format_map[] = {
25 	[EFI_GOT_RGBA8] = { {0, 8}, {8, 8}, {16, 8}, {24, 8} },
26 	[EFI_GOT_BGRA8] = { {16, 8}, {8, 8}, {0, 8}, {24, 8} },
27 };
28 
29 static void efi_find_pixel_bits(u32 mask, u8 *pos, u8 *size)
30 {
31 	u8 first, len;
32 
33 	first = 0;
34 	len = 0;
35 
36 	if (mask) {
37 		while (!(mask & 0x1)) {
38 			mask = mask >> 1;
39 			first++;
40 		}
41 
42 		while (mask & 0x1) {
43 			mask = mask >> 1;
44 			len++;
45 		}
46 	}
47 
48 	*pos = first;
49 	*size = len;
50 }
51 
52 static int save_vesa_mode(struct vesa_mode_info *vesa)
53 {
54 	struct efi_entry_gopmode *mode;
55 	const struct efi_framebuffer *fbinfo;
56 	int size;
57 	int ret;
58 
59 	ret = efi_info_get(EFIET_GOP_MODE, (void **)&mode, &size);
60 	if (ret == -ENOENT) {
61 		debug("efi graphics output protocol mode not found\n");
62 		return -ENXIO;
63 	}
64 
65 	vesa->phys_base_ptr = mode->fb_base;
66 	vesa->x_resolution = mode->info->width;
67 	vesa->y_resolution = mode->info->height;
68 
69 	if (mode->info->pixel_format < EFI_GOT_BITMASK) {
70 		fbinfo = &efi_framebuffer_format_map[mode->info->pixel_format];
71 		vesa->red_mask_size = fbinfo->red.size;
72 		vesa->red_mask_pos = fbinfo->red.pos;
73 		vesa->green_mask_size = fbinfo->green.size;
74 		vesa->green_mask_pos = fbinfo->green.pos;
75 		vesa->blue_mask_size = fbinfo->blue.size;
76 		vesa->blue_mask_pos = fbinfo->blue.pos;
77 		vesa->reserved_mask_size = fbinfo->rsvd.size;
78 		vesa->reserved_mask_pos = fbinfo->rsvd.pos;
79 
80 		vesa->bits_per_pixel = 32;
81 		vesa->bytes_per_scanline = mode->info->pixels_per_scanline * 4;
82 	} else if (mode->info->pixel_format == EFI_GOT_BITMASK) {
83 		efi_find_pixel_bits(mode->info->pixel_bitmask[0],
84 				    &vesa->red_mask_pos,
85 				    &vesa->red_mask_size);
86 		efi_find_pixel_bits(mode->info->pixel_bitmask[1],
87 				    &vesa->green_mask_pos,
88 				    &vesa->green_mask_size);
89 		efi_find_pixel_bits(mode->info->pixel_bitmask[2],
90 				    &vesa->blue_mask_pos,
91 				    &vesa->blue_mask_size);
92 		efi_find_pixel_bits(mode->info->pixel_bitmask[3],
93 				    &vesa->reserved_mask_pos,
94 				    &vesa->reserved_mask_size);
95 		vesa->bits_per_pixel = vesa->red_mask_size +
96 				       vesa->green_mask_size +
97 				       vesa->blue_mask_size +
98 				       vesa->reserved_mask_size;
99 		vesa->bytes_per_scanline = (mode->info->pixels_per_scanline *
100 					    vesa->bits_per_pixel) / 8;
101 	} else {
102 		debug("efi set unknown framebuffer format: %d\n",
103 		      mode->info->pixel_format);
104 		return -EINVAL;
105 	}
106 
107 	return 0;
108 }
109 
110 static int efi_video_probe(struct udevice *dev)
111 {
112 	struct video_uc_platdata *plat = dev_get_uclass_platdata(dev);
113 	struct video_priv *uc_priv = dev_get_uclass_priv(dev);
114 	struct vesa_mode_info *vesa = &mode_info.vesa;
115 	int ret;
116 
117 	/* Initialize vesa_mode_info structure */
118 	ret = save_vesa_mode(vesa);
119 	if (ret)
120 		goto err;
121 
122 	ret = vbe_setup_video_priv(vesa, uc_priv, plat);
123 	if (ret)
124 		goto err;
125 
126 	printf("Video: %dx%dx%d\n", uc_priv->xsize, uc_priv->ysize,
127 	       vesa->bits_per_pixel);
128 
129 	return 0;
130 
131 err:
132 	printf("No video mode configured in EFI!\n");
133 	return ret;
134 }
135 
136 static const struct udevice_id efi_video_ids[] = {
137 	{ .compatible = "efi-fb" },
138 	{ }
139 };
140 
141 U_BOOT_DRIVER(efi_video) = {
142 	.name	= "efi_video",
143 	.id	= UCLASS_VIDEO,
144 	.of_match = efi_video_ids,
145 	.probe	= efi_video_probe,
146 };
147