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 DECLARE_FLEX_ARRAY(u8, raw); 70 }; 71 }; 72 73 /* A driver for handling devices described in coreboot tables. */ 74 struct coreboot_driver { 75 int (*probe)(struct coreboot_device *); 76 void (*remove)(struct coreboot_device *); 77 struct device_driver drv; 78 u32 tag; 79 }; 80 81 /* Register a driver that uses the data from a coreboot table. */ 82 int coreboot_driver_register(struct coreboot_driver *driver); 83 84 /* Unregister a driver that uses the data from a coreboot table. */ 85 void coreboot_driver_unregister(struct coreboot_driver *driver); 86 87 /* module_coreboot_driver() - Helper macro for drivers that don't do 88 * anything special in module init/exit. This eliminates a lot of 89 * boilerplate. Each module may only use this macro once, and 90 * calling it replaces module_init() and module_exit() 91 */ 92 #define module_coreboot_driver(__coreboot_driver) \ 93 module_driver(__coreboot_driver, coreboot_driver_register, \ 94 coreboot_driver_unregister) 95 96 #endif /* __COREBOOT_TABLE_H */ 97