1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * coreboot_table.h
4 *
5 * Internal header for coreboot table access.
6 *
7 * Copyright 2014 Gerd Hoffmann <kraxel@redhat.com>
8 * Copyright 2017 Google Inc.
9 * Copyright 2017 Samuel Holland <samuel@sholland.org>
10 */
11
12 #ifndef __COREBOOT_TABLE_H
13 #define __COREBOOT_TABLE_H
14
15 #include <linux/device.h>
16
17 /* Coreboot table header structure */
18 struct coreboot_table_header {
19 char signature[4];
20 u32 header_bytes;
21 u32 header_checksum;
22 u32 table_bytes;
23 u32 table_checksum;
24 u32 table_entries;
25 };
26
27 /* List of coreboot entry structures that is used */
28 /* Generic */
29 struct coreboot_table_entry {
30 u32 tag;
31 u32 size;
32 };
33
34 /* Points to a CBMEM entry */
35 struct lb_cbmem_ref {
36 u32 tag;
37 u32 size;
38
39 u64 cbmem_addr;
40 };
41
42 /* Describes framebuffer setup by coreboot */
43 struct lb_framebuffer {
44 u32 tag;
45 u32 size;
46
47 u64 physical_address;
48 u32 x_resolution;
49 u32 y_resolution;
50 u32 bytes_per_line;
51 u8 bits_per_pixel;
52 u8 red_mask_pos;
53 u8 red_mask_size;
54 u8 green_mask_pos;
55 u8 green_mask_size;
56 u8 blue_mask_pos;
57 u8 blue_mask_size;
58 u8 reserved_mask_pos;
59 u8 reserved_mask_size;
60 };
61
62 /* A device, additionally with information from coreboot. */
63 struct coreboot_device {
64 struct device dev;
65 union {
66 struct coreboot_table_entry entry;
67 struct lb_cbmem_ref cbmem_ref;
68 struct lb_framebuffer framebuffer;
69 };
70 };
71
72 /* A driver for handling devices described in coreboot tables. */
73 struct coreboot_driver {
74 int (*probe)(struct coreboot_device *);
75 int (*remove)(struct coreboot_device *);
76 struct device_driver drv;
77 u32 tag;
78 };
79
80 /* Register a driver that uses the data from a coreboot table. */
81 int coreboot_driver_register(struct coreboot_driver *driver);
82
83 /* Unregister a driver that uses the data from a coreboot table. */
84 void coreboot_driver_unregister(struct coreboot_driver *driver);
85
86 /* module_coreboot_driver() - Helper macro for drivers that don't do
87 * anything special in module init/exit. This eliminates a lot of
88 * boilerplate. Each module may only use this macro once, and
89 * calling it replaces module_init() and module_exit()
90 */
91 #define module_coreboot_driver(__coreboot_driver) \
92 module_driver(__coreboot_driver, coreboot_driver_register, \
93 coreboot_driver_unregister)
94
95 #endif /* __COREBOOT_TABLE_H */