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 #define LB_TAG_CBMEM_ENTRY 0x31 43 44 /* Corresponds to LB_TAG_CBMEM_ENTRY */ 45 struct lb_cbmem_entry { 46 u32 tag; 47 u32 size; 48 49 u64 address; 50 u32 entry_size; 51 u32 id; 52 }; 53 54 /* Describes framebuffer setup by coreboot */ 55 struct lb_framebuffer { 56 u32 tag; 57 u32 size; 58 59 u64 physical_address; 60 u32 x_resolution; 61 u32 y_resolution; 62 u32 bytes_per_line; 63 u8 bits_per_pixel; 64 u8 red_mask_pos; 65 u8 red_mask_size; 66 u8 green_mask_pos; 67 u8 green_mask_size; 68 u8 blue_mask_pos; 69 u8 blue_mask_size; 70 u8 reserved_mask_pos; 71 u8 reserved_mask_size; 72 }; 73 74 /* A device, additionally with information from coreboot. */ 75 struct coreboot_device { 76 struct device dev; 77 union { 78 struct coreboot_table_entry entry; 79 struct lb_cbmem_ref cbmem_ref; 80 struct lb_cbmem_entry cbmem_entry; 81 struct lb_framebuffer framebuffer; 82 }; 83 }; 84 85 static inline struct coreboot_device *dev_to_coreboot_device(struct device *dev) 86 { 87 return container_of(dev, struct coreboot_device, dev); 88 } 89 90 /* A driver for handling devices described in coreboot tables. */ 91 struct coreboot_driver { 92 int (*probe)(struct coreboot_device *); 93 void (*remove)(struct coreboot_device *); 94 struct device_driver drv; 95 u32 tag; 96 }; 97 98 /* Register a driver that uses the data from a coreboot table. */ 99 int coreboot_driver_register(struct coreboot_driver *driver); 100 101 /* Unregister a driver that uses the data from a coreboot table. */ 102 void coreboot_driver_unregister(struct coreboot_driver *driver); 103 104 /* module_coreboot_driver() - Helper macro for drivers that don't do 105 * anything special in module init/exit. This eliminates a lot of 106 * boilerplate. Each module may only use this macro once, and 107 * calling it replaces module_init() and module_exit() 108 */ 109 #define module_coreboot_driver(__coreboot_driver) \ 110 module_driver(__coreboot_driver, coreboot_driver_register, \ 111 coreboot_driver_unregister) 112 113 #endif /* __COREBOOT_TABLE_H */ 114