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 */
18struct 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 */
29struct coreboot_table_entry {
30	u32 tag;
31	u32 size;
32};
33
34/* Points to a CBMEM entry */
35struct lb_cbmem_ref {
36	u32 tag;
37	u32 size;
38
39	u64 cbmem_addr;
40};
41
42/* Describes framebuffer setup by coreboot */
43struct 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. */
63struct 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. */
73struct 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. */
81int coreboot_driver_register(struct coreboot_driver *driver);
82
83/* Unregister a driver that uses the data from a coreboot table. */
84void 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 */