1 /*
2  * coreboot_table.h
3  *
4  * Internal header for coreboot table access.
5  *
6  * Copyright 2014 Gerd Hoffmann <kraxel@redhat.com>
7  * Copyright 2017 Google Inc.
8  * Copyright 2017 Samuel Holland <samuel@sholland.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License v2.0 as published by
12  * the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19 
20 #ifndef __COREBOOT_TABLE_H
21 #define __COREBOOT_TABLE_H
22 
23 #include <linux/io.h>
24 
25 /* Coreboot table header structure */
26 struct coreboot_table_header {
27 	char signature[4];
28 	u32 header_bytes;
29 	u32 header_checksum;
30 	u32 table_bytes;
31 	u32 table_checksum;
32 	u32 table_entries;
33 };
34 
35 /* List of coreboot entry structures that is used */
36 /* Generic */
37 struct coreboot_table_entry {
38 	u32 tag;
39 	u32 size;
40 };
41 
42 /* Points to a CBMEM entry */
43 struct lb_cbmem_ref {
44 	u32 tag;
45 	u32 size;
46 
47 	u64 cbmem_addr;
48 };
49 
50 /* Describes framebuffer setup by coreboot */
51 struct lb_framebuffer {
52 	u32 tag;
53 	u32 size;
54 
55 	u64 physical_address;
56 	u32 x_resolution;
57 	u32 y_resolution;
58 	u32 bytes_per_line;
59 	u8  bits_per_pixel;
60 	u8  red_mask_pos;
61 	u8  red_mask_size;
62 	u8  green_mask_pos;
63 	u8  green_mask_size;
64 	u8  blue_mask_pos;
65 	u8  blue_mask_size;
66 	u8  reserved_mask_pos;
67 	u8  reserved_mask_size;
68 };
69 
70 /* A device, additionally with information from coreboot. */
71 struct coreboot_device {
72 	struct device dev;
73 	union {
74 		struct coreboot_table_entry entry;
75 		struct lb_cbmem_ref cbmem_ref;
76 		struct lb_framebuffer framebuffer;
77 	};
78 };
79 
80 /* A driver for handling devices described in coreboot tables. */
81 struct coreboot_driver {
82 	int (*probe)(struct coreboot_device *);
83 	int (*remove)(struct coreboot_device *);
84 	struct device_driver drv;
85 	u32 tag;
86 };
87 
88 /* Register a driver that uses the data from a coreboot table. */
89 int coreboot_driver_register(struct coreboot_driver *driver);
90 
91 /* Unregister a driver that uses the data from a coreboot table. */
92 void coreboot_driver_unregister(struct coreboot_driver *driver);
93 
94 /* Initialize coreboot table module given a pointer to iomem */
95 int coreboot_table_init(struct device *dev, void __iomem *ptr);
96 
97 /* Cleanup coreboot table module */
98 int coreboot_table_exit(void);
99 
100 #endif /* __COREBOOT_TABLE_H */
101