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#include <linux/mod_devicetable.h> 17 18/* Coreboot table header structure */ 19struct coreboot_table_header { 20 char signature[4]; 21 u32 header_bytes; 22 u32 header_checksum; 23 u32 table_bytes; 24 u32 table_checksum; 25 u32 table_entries; 26}; 27 28/* List of coreboot entry structures that is used */ 29/* Generic */ 30struct coreboot_table_entry { 31 u32 tag; 32 u32 size; 33}; 34 35/* Points to a CBMEM entry */ 36struct lb_cbmem_ref { 37 u32 tag; 38 u32 size; 39 40 u64 cbmem_addr; 41}; 42 43#define LB_TAG_CBMEM_ENTRY 0x31 44 45/* Corresponds to LB_TAG_CBMEM_ENTRY */ 46struct lb_cbmem_entry { 47 u32 tag; 48 u32 size; 49 50 u64 address; 51 u32 entry_size; 52 u32 id; 53}; 54 55/* Describes framebuffer setup by coreboot */ 56struct lb_framebuffer { 57 u32 tag; 58 u32 size; 59 60 u64 physical_address; 61 u32 x_resolution; 62 u32 y_resolution; 63 u32 bytes_per_line; 64 u8 bits_per_pixel; 65 u8 red_mask_pos; 66 u8 red_mask_size; 67 u8 green_mask_pos; 68 u8 green_mask_size; 69 u8 blue_mask_pos; 70 u8 blue_mask_size; 71 u8 reserved_mask_pos; 72 u8 reserved_mask_size; 73}; 74 75/* A device, additionally with information from coreboot. */ 76struct coreboot_device { 77 struct device dev; 78 union { 79 struct coreboot_table_entry entry; 80 struct lb_cbmem_ref cbmem_ref; 81 struct lb_cbmem_entry cbmem_entry; 82 struct lb_framebuffer framebuffer; 83 DECLARE_FLEX_ARRAY(u8, raw); 84 }; 85}; 86 87static inline struct coreboot_device *dev_to_coreboot_device(struct device *dev) 88{ 89 return container_of(dev, struct coreboot_device, dev); 90} 91 92/* A driver for handling devices described in coreboot tables. */ 93struct coreboot_driver { 94 int (*probe)(struct coreboot_device *); 95 void (*remove)(struct coreboot_device *); 96 struct device_driver drv; 97 const struct coreboot_device_id *id_table; 98}; 99 100/* Register a driver that uses the data from a coreboot table. */ 101int coreboot_driver_register(struct coreboot_driver *driver); 102 103/* Unregister a driver that uses the data from a coreboot table. */ 104void coreboot_driver_unregister(struct coreboot_driver *driver); 105 106/* module_coreboot_driver() - Helper macro for drivers that don't do 107 * anything special in module init/exit. This eliminates a lot of 108 * boilerplate. Each module may only use this macro once, and 109 * calling it replaces module_init() and module_exit() 110 */ 111#define module_coreboot_driver(__coreboot_driver) \ 112 module_driver(__coreboot_driver, coreboot_driver_register, \ 113 coreboot_driver_unregister) 114 115#endif /* __COREBOOT_TABLE_H */ 116